TITLE: Biotechnology: Plant Protection from Nonviral Agents
PUBLICATION DATE: January, 1993
ENTRY DATE: Feb, 1994
EXPIRATION DATE: None
UPDATE FREQUENCY: As needed
CONTACT: Biotechnology Information Center(biotech@nalusda.gov)
National Agricultural Library
DOCUMENT TYPE: Text
DOCUMENT SIZE: 417k, approx. 232 pp.
ISSN: 1052-5378
United States Department of Agriculture National Agricultural Library 10301 Baltimore Blvd. Beltsville, Maryland 20705-2351 Biotechnology: Plant Protection from Nonviral Agents January 1991 - December 1992 QB 93-13 Quick Bibliography Series: QB 93-13 Updates QB 91-82 284 citations from AGRICOLA Daniel Cabirac and Robert Warmbrodt Biotechnology Information Center January 1993 National Agricultural Library Cataloging Record: Cabirac, Daniel Biotechnology, plant protection from non-viral agents. (Quick bibliography series ; 93-13) 1. Plants, Protection of--Bibliography. I. Warmbrodt, Robert D. II. Title. aZ5071.N3 no.93-13 AGRICOLA SEARCH STRATEGY Set Items Description --- ----- ----------- S1 8755 BIOTECH? OR BIOENGINEER? OR RECOMBINANT()DNA OR MICROMANIPULAT? OR TRANSGEN? ORGENETIC?()ENGINEER? S2 6894 (GENE OR GENES OR GENETIC? OR GENOM? OR CHROMOSOM? OR DNA OR RNA)(4N)(CHANG? OR ALTER? OR INSERT? OR MANIPULAT? OR TRANSFER? OR TRANSFORM? OR RECOMBIN? OR SPLIC?) S3 15720 PLASTID? OR COSMID? OR PLASMID? OR PHAGE? OR MONOCLONAL()ANTIBOD? OR HYBRIDOMA? OR VECTOR? OR TRANSPOSON? S4 27466 S1 OR S2 OR S3 S5 10245 S4 AND PY=1989:1992 S6 717 S5 AND (SH=F800 OR SH=F820 OR SH=F822 OR SH=F830 OR SH=F831 OR SH=F832 OR SH=840 OR SH=F850 OR SH=F851) S7 687 S6 NOT (VIRUS? OR VIRAL)/DE S8 314 S6 AND PY=1991:1992 S9 306 S7 AND PY=1991:19921 NAL Call. No.: QH442.A1G4 The a mating-type alleles of Ustilago maydis are idiomorphs. Froeliger, E.H.; Leong, S.A. Amsterdam : Elsevier Science Publishers; 1991. Gene v. 100: p. 113-122; 1991. Includes references. Language: English Descriptors: Ustilago zeae; Alleles; Genetic transformation; Dna; Restriction mapping Abstract: Two unlinked incompatibility loci, a and b, control mating, pathogenicity, and sexual development in Ustilago maydis, a fungal pathogen of corn. Fusion of nonpathogenic haploid cells occurs when alleles of the a locus differ; fusion products that differ at the b locus will be pathogenic and complete sexual development. The two alleles of the a locus have been cloned. The a2 allele was isolated by exploiting the close linkage of the a locus to the genetic marker panI. Several cosmids from a clonal a2 mating-type library allowed, via DNA-mediated transformation, an al mating type, panl-1 auxotrophic recipient to grow prototrophically on medium lacking pantothenic acid. Cosmids containing functional a2 mating-type regions were identified by their ability to confer a2 mating behavior to the a1 recipient strain. The al allele was isolated from a plasmid library using DNA from the a2 region as a hybridization probe. The isolated clones contain al or a2 mating-type specificity as demonstrated by a plate mating assay, by pathogenicity tests on corn, and by gene replacement experiments. The a1 and a2 mating-type clones contain nonhomologous DNA segments that are flanked by similar nucleotide (nt) sequences. Restriction fragments containing a mating-type function are embedded within the nonhomologous DNA segments. U. maydis contains a single copy of either the al or a2 mating-type sequence within each haploid genome. This structural organization demonstrates that the a mating-type alleles of U. maydis are idiomorphs sensu Metzenberg and Glass (1990), nt sequences mapping to the same genetic locus that share no obvious evolutionary relationship. 2 NAL Call. No.: QH442.A1G4 Acquisition of mitochondrial DNA by a transformation vector for Ustilago violacea. Bej, A.K.; Perlin, M.H. Amsterdam : Elsevier Science Publishers; 1991. Gene v. 98 (1): p. 135-140; 1991. Includes references. Language: English Descriptors: Ustilago violacea; Escherichia coli; Genetic transformation; Vectors; Mitochondrial DNA; Plasmids; Restriction mapping Abstract: Plasmid pUCH1 is a 5.2-kb pUC18 construct bearing the hygB gene fused to a promoter from Cochliobolus heterostrophus. Haploid cells of the basidiomycete, Ustilago violacea, were transformed with this plasmid. In addition to multiple integrations of plasmid sequences into U. violacea nuclear DNA, vector sequences independent of the nuclear genome were indicated by Southern-blot analysis using all or part of pUCH1 as a probe. Hybridization also revealed intact pUCH1 and several larger derivatives in satellite bands from CsC1-bis-benzamide gradients of whole cellular DNA and in DNA from purified mitochondria [mitochondrial (mt) DNA preparations] of transformed U. violacea; circular DNAs consistent with the sizes of DNAs in these satellite bands were seen in electron microscope analyses of the same mt DNA preparations as well. The plasmids could be detected in mt DNA preparations even after 30 generations of transformant growth under selective pressure. Transformation of Escherichia coli by these mt DNA preparations produced bacterial transformants bearing intact pUCH1, as well as several pUCH1 derivatives, including pUCH2, an approx. 8.0-kb plasmid. A 2.5-kb EcoRI fragment from pUCH2 showed only weak hybridization with pUCH1. This unique fragment did hybridize strongly with mt DNA from untransformed U. violacea. This derivative thus appears to have acquired mt sequences from U. violacea. 3 NAL Call. No.: 500 N21P Activity of the Agrobacterium T-DNA transfer machinery is affected by virB gene products. Ward, J.E. Jr; Dale, E.M.; Binns, A.N. Washington, D.C. : The Academy; 1991 Oct15. Proceedings of the National Academy of Sciences of the United States of America v. 88 (20): p. 9350-9354; 1991 Oct15. Includes references. Language: English Descriptors: Nicotiana tabacum; Crown gall; Disease resistance; Gene expression; Genetic transformation; Agrobacterium tumefaciens; Dna; Plasmids; Strains; Transfer factor; Virulence Abstract: The oriT (origin of transfer) sequence and mob (mobilization) genes of plasmid RSF1010 can functionally replace transfer DNA (T-DNA) borders to generate an RSF1010 intermediate transferable to plants through activities of the tumor-inducing (Ti)-plasmid virulence (vir) genes of Agrobacterium tumefaciens. Because the Ti plasmid virB gene products are hypothesized to form a membrane-localized T-DNA transport apparatus, we investigated whether specific virB genes were needed for RSF1010 transfer. Here we report that transformation of Nicotiana tabacum leaf explants by an RSF1010-derivative plasmid (pJW323) requires the essential virulence genes virB9, virB10, and virB11, consistent with the hypothesis that both the T-DNA and RSF1010 transfer intermediates utilize the same transport machinery. Further, while pJW323 is transferred into plant cells by Agrobacterium strains harboring both pJW323 and pTiA6, the initiation of crown gall tumors (i.e., T-DNA transfer) is greatly suppressed. Coordinate overexpression of the virB9, virB10, and virB11 gene products relieves pJW323-mediated oncogenic suppression and restores tumorigenicity, but does not increase the transfer frequency of pJW323 into plant cells. We propose that the virB9, virB10, and virB11 gene products function coordinately and stoichiometrically to enhance DNA transfer in a fashion specific for the T-DNA intermediate. 4 NAL Call. No.: QK725.P54 Agrobacterium induced gall formation in lipoxygenase mutant isolines of soybeans. Bhatt, D.; Parrott, W.A.; Collins, G.B.; Hildebrand, D.F. Berlin, W. Ger. : Springer International; 1991. Plant cell reports v. 9 (11): p. 651-654; 1991. Includes references. Language: English Descriptors: Glycine max; Agrobacterium tumefaciens; Genetic transformation; Transgenics; Galls; Pathogenicity; Regulation; Lipoxygenase; Enzyme activity; Mutants; Genetic variation Abstract: Agrobacterium-mediated transformation frequency is very low with cells from some species such as soybeans. Studies were conducted to investigate the Agrobacterium- mediated transformation frequency in near-isogenic lipoxygenase mutant lines of soybeans, since the high level of lipoxygenase activity in soybean embryos might be expected to affect interactions with Agrobacterium. The mutant line lacking lipoxygenase 3 showed significantly greater frequency of Agrobacterium-induced transformation than the other soybean lines. Stages of soybean embryo development which showed maximum differences in lipoxygenase 3 activity between mutant and wild-type, also showed maximum differences in transformation frequency. The increased transformation frequency with the absence of lipoxygenase 3 was only seen when both lipoxygenase 1 and 2 were present. 5 NAL Call. No.: QH442.A1G4 Agrobacterium rhizogenes lacZ-rolC gene expression in Escherichia coli: detection of the product in transgenic plants using RolC-specific antibodies. Oono, Y.; Satomi, T.; Uchimiya, H. Amsterdam : Elsevier Science Publishers; 1991. Gene v. 104 (1): p. 95-98; 1991. Includes references. Language: English Descriptors: Agrobacterium rhizogenes; Genes; Gene expression; Recombinant DNA; Nicotiana tabacum; Transgenics; Escherichia coli; Plasmids Abstract: The rolC sequence of the Agrobacterium rhizogenes Ri plasmid was fused in-frame to the 3' end of the lacZ gene in plasmid pEX3. The fusion protein RolC-beta-galactosidase was accumulated as insoluble inclusion bodies in Escherichia coli. Antibodies were raised in rabbits against the fusion protein. After affinity purification, RolC-specific antibodies were found to react with a 22-kDa polypeptide prepared from roots of transgenic tobacco plants possessing a rolC gene. The result of differential centrifugation suggested that RolC is present in the soluble fraction of transformed cells. 6 NAL Call. No.: 448.3 J82 Agrobacterium tumefaciens transfer extremely long T-DNAs by a unidirectional mechanism. Miranda, A.; Janssen, G.; Hodges, L.; Peralta, E.G.; Ream, W. Washington, D.C. : American Society for Microbiology; 1992 Apr. Journal of bacteriology v. 174 (7): p. 2288-2297; 1992 Apr. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Dna; Plasmids; Transfer Abstract: During crown gall tumorigenesis, part of the Agrobacterium tumefaciens tumor-inducing (Ti) plasmid, the T- DNA, integrates into plant DNA. Direct repeats define the left and right ends of the T-DNA, but tumorigenesis requires only the right-hand repeat. Virulence (vir) genes act in trans to mobilize the T-DNA into plant cells. Transfer of T-DNA begins when the VirD endonuclease cleaves within the right-hand border repeat. Although the T-DNA right-border repeat promotes T-DNA transmission best in its normal orientation, an inverted right border exhibits reduced but significant activity. Two models may account for this diminished tumorigenesis. The right border may function bidirectionally, with strong- activity only in its wild-type orientation, or it may promote T-DNA transfer in a unidirectional manner such that, with an inverted right border, transfer proceeds around the entire Ti plasmid before reaching the T-DNA. To determine whether a substantial portion of the Ti plasmid is transferred to plant cells, as predicted by the unidirectional-transfer hypothesis, we examined T-DNAs in tumors induced by strains containing a Ti plasmid with a right border inverted with respect to the T- DNA oncogenes. These tumors contained extremely long T-DNAs corresponding to most or all of the Ti plasmid. To test whether the right border can function bidirectionally, we inserted T-DNAs with either a properly oriented or an inverted right border into a specific site in the A. tumefaciens chromosome. A border situated to transfer the oncogenes first directed T-DNA transfer even from the bacterial chromosome, whereas a border in the opposite (inverted) orientation did not transfer the oncogenes to plant cells. Our results indicate that the right-border repeat functions in a unidirectional manner. 7 NAL Call. No.: 448.3 J82 The Agrobacterium tumefaciens vir gene transcriptional activator virG is transcriptionally induced by acid pH and other stress stimuli. Mantis, N.J.; Winans, S.C. Washington, D.C. : American Society for Microbiology; 1992 Feb. Journal of bacteriology v. 174 (4): p. 1189-1196; 1992 Feb. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Genes; Proteins; Stress; Pathogenesis; Ph Abstract: A set of Agrobacterium tumefaciens operons required for pathogenesis is coordinately induced during plant infection by the VirA and VirG proteins. The intracellular concentration of VirG increases in response to acidic media, and this response was proposed to be regulated at the level of transcription at a promoter (P2) that resembles the Escherichia coli heat shock promoters. To test this hypothesis, we first constructed a virG-lacZ transcriptional fusion. A strain containing this fusion had higher levels of beta-galactosidase activity in acidic media than in media at neutral pH. Second, primer extension analysis of virG indicated that acidic media stimulated the transcription of this promoter. To determine whether P2 is a member of a heat shock-like regulon in A. tumefaciens, five agents that induce E. coli heat shock genes were tested for their abilities to induce a P2-lacZ fusion in A. tumefaciens. P2 was most strongly induced by low pH, was moderately stimulated by CdCl2 or mitomycin C, and was slightly induced by alkaline pH or ethanol. Heat shock or growth at high temperature did not cause detectable induction of P2 as measured by beta- galactosidase activity and primer extension analysis. Induction by these treatments did not require any Ti plasmid- encoded function or the chromosomally encoded RecA protein. We also pulse-labeled cellular proteins after a shift to low pH and detected several proteins whose synthesis was induced by these conditions. We conclude that P2 is primarily induced by acid pH and secondarily by certain other stimuli, each of which is stressful to cell growth. This stress induction is at least partly independent of the heat shock and SOS responses. 8 NAL Call. No.: 450 P5622 Agrobacterium vir-inducing activities of glycosylated acetosyringone, acetovanillone, syringaldehyde and syringic acid derivatives. Delmotte, F.M.; Delay, D.; Cizeau, J.; Guerin, B.; Leple, J.C. Oxford : Pergamon Press; 1991. Phytochemistry v. 30 (11): p. 3549-3552; 1991. Includes references. Language: English Descriptors: Plant pathogenic bacteria; Agrobacterium tumefaciens; Pathogenicity; Induction; Tumors; Syringic acid; Derivatives; Vanillic acid; Glycosides; Genetic regulation; Virulence; Gene expression Abstract: Expression of the Agrobacterium tumefaciens virulence (vir) gene is known to be dependent on host plant phenolic compounds. The A. tumefaciens strain A348 (psM358) harbouring a virE::lacZ fusion plasmid was used to detect the ability of 13 synthetic acetosyringone, acetovanillone, syringaldehyde and syringic acid beta-glycosides to induce virulence. The activity of the reporter beta-galactosidase was detected by spectrofluorimetry using 4-methylumbelliferyl beta-galactopyranoside as substrate. Acetosyringonyl beta-L- fucopyranoside was the most active monoglycoside tested; even at high concentration this compound was devoid of toxic effects, However, monoglycosides were less active vir inducers than free acetosyringone. In contrast, the beta-maltoside of syringaldehyde showed higher activity than the free phenol at high concentration. The activity of such glycosylated inducers may be related to specific sugar receptors on the bacterial cell surface. 9 NAL Call. No.: QH301.N32 Agrobacterium-mediated transformation of apple (Malus pumila Mill). James, D.J. New York, N.Y. : Plenum Press; 1991. NATO ASI series : Series A : Life sciences v. 210: p. 213-226; 1991. In the series analytic: Woody plant biotechnology / edited by M.R. Ahuja. Proceedings of a Workshop at the Institute of Forest Genetics, USDA Forest Service, October 15-19, 1989, Placerville, California. Literature review. Includes references. Language: English Descriptors: Malus pumila; Genetic transformation; Agrobacterium tumefaciens; Cultivars; Explants; Leaves; Organogenesis; Rooting; Transgenics; Literature reviews 10 NAL Call. No.: 442.8 Z34 Analysis of a high frequency transformation system for Ophiostoma ulmi, the causal agent of Dutch elm disease. Royer, J.C.; Dewar, K.; Hubbes, M.; Horgen, P.A. Berlin, W. Ger. : Springer International; 1991 Jan. M G G : Molecular and general genetics v. 225 (1): p. 168-176. ill; 1991 Jan. Includes references. Language: English Descriptors: Ceratocystis ulmi; Genetic transformation; Direct DNAuptake; Protoplasts; Plasmids; Gene transfer; Reporter genes; Hygromycin b; Drug resistance; Phosphotransferases; Repetitive DNA; Promoters; Southern blotting; Electrophoresis; Mitosis Abstract: A transformation system for Ophiostoma ulmi (Buism.) Nannf. was developed and analyzed. Protoplasts were generated from actively budding yeastlike cells by digestion with NovoZym 234 in MgSO4 after pretreatment with 2- mercaptoethanol. Protoplast regeneration was most efficient when 0.6 M sucrose was used as the osmoticum. Several plasmids containing fusions between fungal promoters and a bacterial gene for hygromycin phosphotransferase successfully transformed O. ulmi to hygromycin resistance. One of these vectors, pPS57, which contains a promoter for isopenicillin N synthetase from Penicillium chrysogenum, consistently conferred the greatest resistance to hygromycin. Linearization of the vector and inclusion of 2-mercaptoethanol in the transformation reaction resulted in enhanced transformation efficiency. Approximately 4 X 10(3) transformants /microgram DNA per 10(7) protoplasts were obtained using the optimized procedure. Southern hybridization after alternating field and standard electrophoresis suggested random insertion of tandem repeats (some greater than 250 kb) into the fungal chromosomes. Antibiotic resistance was stable through mitosis. However, expression of the transforming DNA after meiosis was highly variable. 11 NAL Call. No.: QK710.P62 Analysis of cis-regulatory elements involved in induction of a tobacco PR-5 gene by virus infection. Albrecht, H.; Rhee, M.D. van de; Bol, J.F. Dordrecht : Kluwer Academic Publishers; 1992 Jan. Plant molecular biology : an international journal on molecular biology, biochemistry and genetic engineering v. 18 (1): p. 155-158; 1992 Jan. Includes references. Language: English Descriptors: Nicotiana tabacum; Tobacco mosaic tobamovirus; Gene expression; Pathogenesis-related proteins; Genes; Controlling elements; Genetic regulation; Infections; Disease resistance; Transgenics; Beta-glucuronidase; Reporter genes Abstract: cis-Regulatory elements involved in tobacco mosaic virus (TMV)-inducible expression were identified in a tobacco PR-5 gene, encoding an acidic thaumatin-like protein. By fusing upstream sequences of the PR-5 gene to the GUS reporter gene and analysing transgenic plants containing these fusions for local and systemic induction of GUS activity by TMV, it was found that sequences between -1364 and -718 are involved in TMV induction of PR-5 gene expression. 12 NAL Call. No.: 464.8 P56 The analysis of plasmid-mediated streptomycin resistance in Erwinia amylovora. Chiou, C.S.; Jones, A.L. St. Paul, Minn. : American Phytopathological Society; 1991 Jul. Phytopathology v. 81 (7): p. 710-714; 1991 Jul. Includes references. Language: English Descriptors: Michigan; Malus; Erwinia amylovora; Strains; Mutants; Drug resistance; Streptomycin; Genes; Plasmids; Dna probes; Dna hybridization; Strain differences; Sexual reproduction Abstract: Streptomycin-resistant mutants of Erwinia amylovora were isolated from an apple orchard in Michigan and from crabapple trees adjacent to the same orchard in 1990. Isolates that grew on King's medium B amended with 100 microgram/ml of streptomycin sulfate were considered to be resistant strains, whereas isolates that failed to grow on this medium were considered to be sensitive strains. Growth of the resistant strains was not inhibited in a filter-paper disk assay (0.06-5 microgram of streptomycin sulfate), but growth of sensitive strains was inhibited at concentrations as low as 0.06 microgram of streptomycin sulfate. Only sensitive strains were detected in an additional 19 apple orchards sampled for resistant strains. In colony blot hybridizations, an internal portion of the streptomycin-resistance gene (probe SMP3) from strain Psp36 of Pseudomonas syringae pv. papulans hybridized with all streptomycin-resistant strains of E. amylovora, but not with streptomycin-sensitive strains. Probe SMP3 hybridized to a 2.7-kb restriction fragment from AvaI-digested total genomic and plasmid DNA of two resistant strains of E. amylovora and to a 1.5-kb fragment in DNA from strain Psp36 of P. s. papulans. The probe did not hybridize with digested DNA from sensitive strains. A 33-kb plasmid was present in all streptomycin-resistant field strains but not in streptomycin- sensitive strains. Streptomycin resistance was transferred by matings to four streptomycin-sensitive recipient strains of E. amylovora from each of two streptomycin-resistant donor strains. Transconjugants also contained the 33-kb plasmid. DNA from resistant strain Ea88-90 from Washington did not hybridize with the probe, indicating that this strain contains a resistance system unrelated to that in streptomycin-resistant strains from Michigan. 13 NAL Call. No.: 464.8 P56 Application of electroporation for efficient transformation of Xanthomonas campestris pv. oryzae. White, T.J.; Gonzalez, C.F. St. Paul, Minn. : American Phytopathological Society; 1991 May. Phytopathology v. 81 (5): p. 521-524; 1991 May. Includes references. Language: English Descriptors: Oryza sativa; Xanthomonas campestris pv. oryzae; Strains; Genetic transformation; Electroporation; Plasmids; Dna Abstract: Electroporation provided an effective transformation system for strains of Xanthomonas campestris pv. oryzae. Transformation was observed for strain X37-2 with plasmid pUFR027 over a range of electric field strengths (9.2-17.1 kV/cm) and two different pulse lengths. Optimization of the compensatory relationship between the electrical parameters produced maximal transformation efficiency (3.6 X 10(9) transformants/microgram DNA) and frequency (1.8 X 10-2 transformant/survivor) for strain X37-2. When applied to four other strains of X. c. oryzae, these conditions yielded lower levels of transformation (7.8 X 10(6) to 2.7 X 10(7) transformants/microgram DNA). Linear relationships were observed between bacterial cell density and transformation efficiency and between plasmid DNA concentration and frequency of transformation. 14 NAL Call. No.: QH442.G4 Approaches and progress in the molecular cloning of plant disease resistance genes. Bennetzen, J.L.; Jones, J.D.G. New York, N.Y. : Plenum Press; 1992. Genetic engineering : Principles and methods v. 14: p. 99-124; 1992. Literature review. Includes references. Language: English Descriptors: Plant; Plant pathogens; Plant diseases; Genetic resistance; Genes; Cloning; Horizontal resistance; Vertical resistance; Genetic engineering; Literature reviews 15 NAL Call. No.: 500 N484 Arabidopsis as a model system for studying plant disease resistance mechanisms. Innes, R.; Bent, A.; Whalen, M.; Staskawicz, B. New York, N.Y. : The Academy; 1991. Annals of the New York Academy of Sciences v. 646: p. 228-230; 1991. In the series analytic: Recombinant DNA technology I / edited by A. Prokop and R.K. Bajpai. Includes references. Language: English Descriptors: Arabidopsis thaliana; Cultivars; Gene mapping; Genetic resistance; Pseudomonas syringae pv. tomato; Resistance mechanisms 16 NAL Call. No.: SB732.6.M65 At least six avirulence genes are clustered on a 90-kilobase plasmid in Xanthomonas campestris pv. malvacearum. De Feyter, R.; Gabriel, D.W. St. Paul, Minn. : APS Press; 1991 Sep. Molecular plant-microbe interactions : MPMI v. 4 (5): p. 423-432; 1991 Sep. Includes references. Language: English Descriptors: Gossypium hirsutum; Xanthomonas campestris pv. malvacearum; Strains; Virulence; Genes; Strain differences; Host specificity; Disease resistance; Genetic resistance; Horizontal resistance; Vertical resistance; Plasmids; Genome analysis; Dna libraries; Gene mapping 17 NAL Call. No.: SB327.A1B5 Attempting genetic transformation of bean by high velocity microporjectiles. Allavena, A.; Bernacchia, G. Fort Collins, Colo : Howard F. Schwartz, Colorado State University; 1991. Annual report of the Bean Improvement Cooperative v. 34: p. 137-138; 1991. Includes references. Language: English Descriptors: Phaseolus vulgaris; Agrobacterium; Dna; Genetic transformation; Infection 18 NAL Call. No.: 470 C16C Axenic culture of the downy mildew fungus Plasmopara halstedii in Agrobacterium rhizogenes-induced roots of sunflower (Helianthus annuus). Zahka, G.A.; Viranyi, F. Ottawa, Ont. : National Research Council of Canada; 1991 Dec. Canadian journal of botany; Journal canadien de botanique v. 69 (12): p. 2709-2715; 1991 Dec. Includes references. Language: English Descriptors: Helianthus annuus; Plasmopara halstedii; Plant pathogenic fungi; In vitro culture; Roots; Agrobacterium rhizogenes; Transgenics; Culture techniques; Pathogenicity; Infectivity; Spore germination; Fungal morphology 19 NAL Call. No.: 464.8 P56 A bacteriophage-typing system for surveying the diversity and distribution of strains of Erwinia carotovora in potato fields. Gross, D.C.; Powelson, M.L.; Regner, K.M.; Radamaker, G.K. St. Paul, Minn. : American Phytopathological Society; 1991 Feb. Phytopathology v. 81 (2): p. 220-226; 1991 Feb. Includes references. Language: English Descriptors: Solanum tuberosum; Erwinia carotovora subsp. carotovora; Erwinia carotovora subsp. atroseptica; Strains; Strain differences; Detection; Identification; Bacteriophages; Serotypes; Serological relationships; Disease surveys Abstract: A bacteriophage-typing system was developed and used to survey the diversity and distribution among strains of Erwinia carotovora subsp. carotovora and E.c. subsp. atroseptica from the rhizospheres and stems of potatoes grown in the Columbia Basin of the Pacific Northwest. With a phage enrichment method and strains of E. carotovora from 25 serogroups as hosts, 13 phages displaying distinct host-range activities were isolated from potato and soil samples. In addition, a potato strain of E. chrysanthemi was used to isolate phage N (Ech-3), which did not infect strains of E. carotovora. All strains of E. c. atroseptica were sensitive to at least one of five phages, and strains in both subspecies of E. carotovora were sensitive to phage isolates C (304-32), E (101-1), and J (465-2-3-6). In three commercial fields in 1981, the phage groups occurring at midseason were AEJ, E, and EJ for E. c. atroseptica and G, GI, EF, and F for E. c. carotovora; total rhizosphere and stem populations of E. carotovora from symptomless plants ranged from 2 X 10(3) to 3 X 10(6) cfu g (fresh weight) at midseason. In 1982, numbers of E. carotovora recovered from stems and rhizospheres increased from low and sporadic levels in late May to over 10(5) cfu/g (fresh weight) by early July. Phage group EJ of E. c. atroseptica was predominant among the strains from Norgold Russet and Russet Burbank seed tubers, and it composed 35-43% of the total strains of E. carotovora recovered from rhizosphere and stem samples later in the season. No specific phage group was clearly associated with cultivar, date of isolation, and either rhizosphere or stem samples. Of the 389 strains of E. carotovora collected over a 2-yr period, 44% and 48% were typed, respectively, to one of 14 phage groups and one of nine serogroups. All strains of E. c. atroseptica were members of serogroup I, whereas IV and XXXVII were the two most common serogroups of E. c. carotovora. A few phage groups and serogroups were composed of t 20 NAL Call. No.: 381 J824 Biochemical and molecular characterization of three barley seed proteins with antifungal properties. Leah, R.; Tommerup, H.; Svendsen, I.; Mundy, J. Baltimore, Md. : American Society for Biochemistry and Molecular Biology; 1991 Jan25. The Journal of biological chemistry v. 266 (3): p. 1564-1573. ill; 1991 Jan25. Includes references. Language: English Descriptors: Hordeum vulgare; Seeds; Plant proteins; Antifungal properties; Chitinase; Beta-glucanase; Purification; Amino acid sequences; Nucleotide sequences; Dna probes Abstract: We have purified three proteins from barley (Hordeum vulgare L.) seeds which synergistically inhibit the growth of fungi measured in a microtiter well assay. The proteins are a 26-kDa chitinase, a 30-kDa ribosome- inactivating protein, and a 32-kDa (1-3)-beta-glucanase. Full- length cDNAs encoding them were isolated and sequenced to determine the complete primary structures of the proteins. Northern hybridizations with the cDNAs as probes showed that the corresponding mRNAs accumulate differentially during seed development and germination. Chitinase mRNA accumulates to high levels in aleurone cells during late seed development and early germination, while high levels of mRNA encoding the ribosome-inactivating protein accumulate only in the starchy endosperm during late seed development. The glucanase mRNA accumulates to low levels during seed development and to higher levels in aleurone and seedling tissues during germination. Southern hybridizations showed that the three proteins are encoded by small families of three to eight genes. Their biological roles and potential use in genetic engineering studies are discussed. 21 NAL Call. No.: 448.3 AP5 Biolistic transformation of a procaryote, Bacillus megaterium. Shark, K.B.; Smith, F.D.; Harpending, P.R.; Rasmussen, J.L.; Sanford, J.C. Washington, D.C. : American Society for Microbiology; 1991 Feb. Applied and environmental microbiology v. 57 (2): p. 480-485. ill; 1991 Feb. Includes references. Language: English Descriptors: Bacillus megaterium; Dna; Genetic transformation; Laboratory methods; Plasmids Abstract: We present a simple and rapid method for introducing exogenous DNA into a bacterium, Bacillus megaterium, utilizing the recently developed biolistic process. A suspension of B. megaterium was spread onto the surface of nonselective medium. Plasmid pUB11O DNA, which contains a gene that confers kanamycin resistance, was precipitated onto tungsten particles. Using a biolistic propulsion system, the coated particles were accelerated at high velocities into the B. megaterium recipient cells. Selection was done by use of an agar overlay containing 50 microgram of kanamycin per ml. Antibiotic-resistant transformants were recovered from the medium interface after 72 h of incubation, and the recipient strain was shown to contain the delivered plasmid by agarose gel electrophoresis of isolated plasmid DNA. All strains of B. megaterium tested were successfully transformed by this method, although transformation efficiency varied among strains. Physical variables of the biolistic process and biological variables associated with the target cells were optimized, yielding transformants per treated plate. This is the first report of the biolistic transformation of a procaryote. 22 NAL Call. No.: Q320.A4 Biotech boosts seed proteins that halt feeding: a technology to protect stored grains. Cutler, K. Cedar Falls, Iowa : Freiberg Pub; 1991 May. AgBiotechnology news v. 8 (3): p. 12, 19; 1991 May. Language: English Descriptors: Amylases; Genetic engineering; Usda; Grain stores; Insect pests; Biological control 23 NAL Call. No.: TP669.I57 Biotechnology & oilseeds. Dotson, K. Champaign, Ill. : American Oil Chemist's Society; 1991 Jun. International news on fats, oils and related materials v. 2 (6): p. 508-510, 512-513, 516-519, 522-523; 1991 Jun. Language: English Descriptors: Oilseed plants; Biotechnology; Genetic engineering; Fatty acids; Pest control 24 NAL Call. No.: QL391.N4J62 Breeding plants for resistance to nematodes. Boerma, H.R.; Hussey, R.S. Lake Alfred, Fla. : Society of Nematologists; 1992 Jun. Journal of nematology v. 24 (2): p. 242-252; 1992 Jun. Literature review. Includes references. Language: English Descriptors: Glycine max; Heterodera glycines; Pest resistance; Plant breeding; Genetic variation; Inheritance; Screening; Restriction fragment length polymorphism; Literature reviews Abstract: Plant breeders and nematologists have developed improved cultivars of important crop species with resistance to plant-parasitic nematodes. The effectiveness of these breeding efforts has depended on the availability of efficient screening procedures, identification of adequate sources of durable resistance, nature of the nematode feeding habit, and knowledge of the inheritance of resistance. These factors determine to a large degree the breeding method and potential success of the research. Systematic searches for nematode resistance have identified resistant germplasm lines within crop species or from related species. When the resistance gene(s) is from related species, incongruity barriers or sterility of the resulting hybrids often must be overcome. In these situations, backcrossing is usually necessary to incorporate the resistance gene(s) and recover the desirable commercial traits of the crop species. If the resistance gene(s) is present within the crop species, the choice of breeding method depends on the inheritance of the resistance, type of screening procedure, and other important breeding objectives for the species. In the future, plant molecular biologists and geneticists will make available novel sources of nematode resistance through incorporation of transgenes from other genera. These efforts will likely require conventional breeding strategies before commercial utilization of an improved resistant cultivar. 25 NAL Call. No.: 382 P56 Carotenoids of Erwinia herbicola and an Escherichia coli HB101 strain carrying the Erwinia herbicola carotenoid gene cluster. Hundle, B.S.; Beyer, P.; Kleinig, H.; Englert, G.; Hearst, J.E. Oxford : Pergamon Press; 1991 Jul. Photochemistry and photobiology v. 54 (1): p. 89-93; 1991 Jul. Includes references. Language: English Descriptors: Erwinia herbicola; Carotenoids; Biosynthesis; Biochemical pathways; Plasmids; Transformation; Escherichia coli Abstract: Carotenoid pigments of Erwinia herbicola and a transformed strain of Escherichia coli carrying the carotenoid biosynthesis gene cluster of E. herbicola have been analyzed. Both organisms are capable of making essentially the same carotenoids, indicating that all of the genes required for the biosynthesis of the wild type E. herbicola carotenoids have been transformed intact into E. coli. The major products in both species of bacteria are beta-cryptoxanthin glucoside, zeaxanthin monoglucoside and zeaxanthin diglucoside. These compounds are the first example of secondary, non-allylic carotenoid glucosides. The absolute configuration 3R,3'R for zeaxanthin diglucoside was determined from its circular dichroism spectrum. Both species of bacteria also accumulate small amounts of hydrocarbon carotenes with similar cis/trans isomerization states. 26 NAL Call. No.: SB732.6.M65 Characterization of a DNA region required for production of the phytotoxin coronatine by Pseudomonas syringae pv. tomato. Ma, S.W.; Morris, V.L.; Cuppels, D.A. St. Paul, Minn. : APS Press; 1991 Jan. Molecular plant-microbe interactions : MPMI v. 4 (1): p. 69-74; 1991 Jan. Includes references. Language: English Descriptors: Lycopersicon esculentum; Pseudomonas syringae pv. tomato; Pathogenicity; Phytotoxins; Biosynthesis; Genetic regulation; Genetic analysis; Dna; Insertional mutagenesis; Mutants; Ice nucleation; Gene expression; Host parasite relationships 27 NAL Call. No.: 448.3 J82 Characterization of a putative periplasmic transport system for octopine accumulation encoded by Agrobacterium tumefaciens Ti plasmid pTiA6. Valdivia, R.H.; Wang, L.; Winans, S.C. Washington, D.C. : American Society for Microbiology; 1991 Oct. Journal of bacteriology v. 173 (20): p. 6398-6405; 1991 Oct. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Octopine; Catabolism; Plasmids; Protein transport; Nucleotide sequences; Amino acid sequences; Enzymes; Genes Abstract: Neoplastic crown gall tumors incited by Agrobacterium tumefaciens release novel amino acid or sugar derivatives known as opines, whose synthesis is directed by genes transferred to plant cells. Agrobacterium cells can transport and catabolize these compounds as sources of carbon and nitrogen. This article describes a region of the pTiA6 plasmid which is required for catabolism of the opine octopine and whose transcription is induced by octopine. This region of the plasmid contains four open reading frames, occQ, occM, occP, and occJ, which show homology to the family of so-called shock-sensitive permeases. TnphoA mutagenesis demonstrated that the OccJ and OccM proteins lie fully or partly in the periplasmic space. The OccJ protein was identified by electrophoresis and found to be fully localized in the periplasmic space. When these proteins were expressed in Escherichia coli, radiolabeled octopine became cell- associated. 28 NAL Call. No.: 448.3 AP5 Characterization of an unusual new Agrobacterium tumefaciens strain from Chrysanthemum morifolium ram. Bush, A.L.; Pueppke, S.G. Washington, D.C. : American Society for Microbiology; 1991 Sep. Applied and environmental microbiology v. 57 (9): p. 2468-2472; 1991 Sep. Includes references. Language: English Descriptors: Dendranthema morifolium; Agrobacterium tumefaciens; Strains; Characterization; Pathogenicity; Glycine max; Host range; Catabolism Abstract: We characterized five isolates of Agrobacterium tumefaciens from naturally occurring galls on Chrysanthemum morifolium. The isolates are similar, possibly identical, members of a single strain of A. tumefaciens that we designate Chry5. The strain is a biotype I, as indicated by its response to both newly described and traditional biotype tests. Chry5 produces tumors on at least 10 plant species. It is unusual in its ability to form efficiently large tumors on soybean (Glycine max), a species normally refractory to transformation. Chry5 is unable to utilize octopine or mannopine as a carbon source. Although Chry5 can catabolize a single isomer each of nopaline and succinamopine, it differs from other known nopaline and succinamopine strains in its insensitivity to agrocin 84. This pattern of opine catabolism is unique among Agrobacterium strains examined to date. All five isolates of Chry5 contain at least two plasmids, one of which shares homology with pTiB6. 29 NAL Call. No.: 448.3 AP5 Characterization of fluorescent siderophore-mediated iron uptake in Pseudomonas sp. strain M114: evidence for the existence of an additional ferric siderophore receptor. Morris, J.; O'Sullivan, D.J.; Koster, M.; Leong, J.; Weisbeek, P.J.; O'Gara, F. Washington, D.C. : American Society for Microbiology; 1992 Feb01. Applied and environmental microbiology v. 58 (2): p. 630-635; 1992 Feb01. Includes references. Language: English Descriptors: Plant disease control; Pseudomonas; Strains; Siderophores; Receptors; Uptake; Iron; Proteins; Mutants; Biological control agents Abstract: In Pseudomonas sp. strain M114, the outer membrane receptor for ferric pseudobactin M114 was shown to transport ferric pseudobactins B10 and A225, in addition to its own. The gene encoding this receptor, which was previously cloned on pCUP3, was localized by Tn5 mutagenesis to a region comprising > 1.6 kb of M114 DNA. A mutant (strain M114R1) lacking this receptor was then created by a marker exchange technique. Characterization of this mutant by using purified pseudobactin M114 in radiolabeled ferric iron uptake studies confirmed that it was completely unable to utilize this siderophore for acquisition of iron. In addition, it lacked an outer membrane protein band of 89 kDa when subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. As a result, growth of the mutant was severely restricted under low-iron conditions. However, this phenotype was reversed in the presence of another fluorescent siderophore (pseudobactin MT3A) from Pseudomonas sp. strain MT3A, suggesting the presence of a second receptor in strain M114. Furthermore, wild-type Pseudomonas sp. strain B24 was not able to utilize ferric pseudobactin MT3A, and this phenotype was not reversed upon expression of the M114 receptor encoded on pCUP3. However, a cosmid clone (pMS1047) that enabled strain B24 to utilize ferric pseudobactin MT3A was isolated from an M114 gene bank. Radiolabel transport assays with purified pseudobactin MT3A confirmed this event. Plasmid pMS1047 was shown to encode an outer membrane protein of 81 kDa in strain B24 under iron-limiting conditions; this protein corresponds to a similar protein in strain M114. 30 NAL Call. No.: 442.8 Z34 Characterization of the supervirulent virG gene of the Agrobacterium tumefaciens plasmid pTiBo542. Chen, C.Y.; Wang, L.; Winans, S.C. Berlin, W. Ger. : Springer International; 1991 Nov. M G G : Molecular and general genetics v. 230 (1/2): p. 302-309; 1991 Nov. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Genes; Virulence; Nucleotide sequences; Plasmids; Promoters; Bacterial proteins; Gene expression Abstract: The virG gene of the Agrobacterium tumefaciens Ti plasmid pTiBo542 has previously been reported to elicit stronger vir gene expression than its counterpart in the pTiA6 plasmid, a property we call the "superactivator" phenotype. The DNA sequence of the pTiBo542 virG gene was determined and compared to that of the pTiA6 gene. The DNA sequences of these genes differ at 16 positions: two differences are in the promoter regions, 12 are in the coding regions, and two are in the 3' untranslated regions. The 3' end of the pTiA6 virG gene also contains a probable insertion sequence that is not found downstream of the pTiBo542 gene. The base pair differences in the two coding regions result in only two amino acid differences, both in the aminoterminal halves of the proteins. Five hybrid virG genes were constructed and used to activate the expression of a virB::lacZ gene fusion. Differences in the coding regions of these genes accounted for most of the superactivator phenotype, while differences at the promoter and 3' untranslated regions also contributed. These findings suggest that the properties of these VirG proteins and their quantities are important for vir gene induction, and also suggest a long-term selective pressure for mutations contributing to differences between these two genes. 31 NAL Call. No.: 448.3 J82 Characterization of three Agrobacterium tumefaciens avirulent mutants with chromosomal mutations that affect induction of vir genes. Metts, J.; West, J.; Doares, S.H.; Matthysse, A.G. Washington, D.C. : American Society for Microbiology; 1991 Feb. Journal of bacteriology v. 173 (3): p. 1080-1087. ill; 1991 Feb. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Mutants; Genes; Virulence; Chromosomes; Lipopolysaccharides Abstract: Three Agrobacterium tumefaciens mutants with chromosomal mutations that affect bacterial virulence were isolated by transposon mutagenesis. Two of the mutants were avirulent on all hosts tested. The third mutant, Ivr-211, was a host range mutant which was avirulent on Bryophyllum diagremontiana, Nicotiana tabacum, N. debneyi, N. glauca, and Daucus carota but was virulent on Zinnia elegans and Lycopersicon esculentum (tomato). That the mutant phenotype was due to the transposon insertion was determined by cloning the DNA containing the transposon insertion and using the cloned DNA to replace the wild-type DNA in the parent bacterial strain by marker exchange. The transposon insertions in the three mutants mapped at three widely separated locations on the bacterial chromosome. The effects of the mutations on various steps in tumor formation were examined. All three mutants showed no alteration in binding to carrot cells. However, none of the mutants showed any induction of vir genes by acetosyringone under conditions in which the parent strain showed vir gene induction. When the mutant bacteria were examined for changes in surface components, it was found that all three of the mutants showed a similar alteration in lipopolysaccharide (LPS). LPS from the mutants was larger in size and more heavily saccharide substituted than LPS from the parent strain. Two of the mutants showed no detectable alteration in outer membrane and periplasmic space proteins. The third mutant, Ivr-225, was missing a 79-kDa surface peptide. The reason(s) for the failure of vir gene induction in these mutants and its relationship, if any, to the observed alteration in LPS are unknown. 32 NAL Call. No.: 442.8 Z34 Characterization of two beta-tubulin genes from Geotrichum candidum. Gold, S.E.; Casale, W.L.; Keen, N.T. Berlin, W. Ger. : Springer International; 1991 Nov. M G G : Molecular and general genetics v. 230 (1/2): p. 104-112; 1991 Nov. Includes references. Language: English Descriptors: Geotrichum candidum; Endomycetales; Trichoderma hamatum; Genes; Introns; Tubulin; Promoters; Nucleotide sequences; Amino acid sequences; Genetic transformation; Gene expression; Restriction mapping Abstract: The beta-tubulin genes G beta 1 and G beta 1 G beta 2 from phytopathogenic hemiascomycete Geotrichum candidum were found to be highly diverged in amino acid sequence from those of other filamentous fungi. G beta 1 and G beta 2 were also divergent from each other, with the coding regions sharing only 66% nucleotide sequence homology and 64% amino acid identity. However, the proteins shared 82% similarity and only 25 of the 161 non-identical amino acid substitutions were non- conservative. The organization of G beta 1 is similar to other fungal beta-tubulin genes, but G beta 2 has several unusual features; it has 2 amino acid additions in the N-terminal 40 residues and must employ an uncommon 5' splice junction sequence in preference to an overlapping perfect consensus. The amino acid change found to confer benomyl resistance in Neurospora crassa was also present in G beta 2. G beta 1 has four introns which are located similarly to those of beta- tubulin genes in other fungi. G beta 2, however, has a single intron in a unique location. Translational fusions employing the 5' non-coding regions of the two Geotrichum beta-tubulin genes were made with the hygromycin phosphotransferase gene and shown to function in Schizosaccharomyces pombe and Trichoderma hamatum. However, G. candidum could not be transformed with these or other tested plasmids commonly used for fungal transformation. 33 NAL Call. No.: 448.3 AP5 Chemotaxis of Pseudomonas syringae subsp. savastanoi virulence mutants. Soby, S.; Kirkpatrick, B.; Kosuge, T. Washington, D.C. : American Society for Microbiology; 1991 Oct. Applied and environmental microbiology v. 57 (10): p. 2918-2920; 1991 Oct. Includes references. Language: English Descriptors: Pseudomonas syringae pv. savastanoi; Mutants; Genes; Virulence; Chemotaxis; Iaa; Deficiency; Adenosine; Motility Abstract: Several mutants of Pseudomonas syringae subsp. savastanoi were tested for their ability to sense a to a chemotactic gradient in low concentrations of yeast extract. The mutants were deficient in one or both of the genes coding for the synthesis of the plant hormones indole-3-acetic acid (IAA) and isopentenyl adenosine. Mutations which resulted in the loss of IAA production were due to the loss of the entire plasmid containing the iaa operon or to an 18-kb deletion of the IAA region. Additional mutants tested were deficient in their ability to produce isopentenyl adenosine as a result of the loss of the ptz-bearing plasmid. In all cases, strains which had lost the ability to produce IAA exhibited enhanced motility of up to 2.5 times that of the wild type (IAA+) in medium containing 0.01% yeast extract. No differences in motility were observed on medium containing lower concentrations of yeast extract. The presence or absence of the cytokinin plasmid and the presence or absence of inorganic nitrogen in the medium had no effect on the relative mobility of the strains. 34 NAL Call. No.: 448.3 J82 The cloned avirulence gene avrPto induces disease resistance in tomato cultivars containing the Pto resistance gene. Ronald, P.C.; Salmeron, J.M.; Carland, F.M.; Staskawicz, B.J. Washington, D.C. : American Society for Microbiology; 1992 Mar. Journal of bacteriology v 174 (5): p. 1604-1611; 1992 Mar. Includes references. Language: English Descriptors: Lycopersicon esculentum; Pseudomonas syringae pv. tomato; Genes; Disease resistance; Glycine max; Cultivars; Virulence Abstract: Resistance of tomato plants to the bacterial pathogen Pseudomonas syringae pv. tomato race 0 is controlled by the locus Pto. A bacterial avirulence gene was cloned by constructing a cosmid library from an avirulent P. syringae pv. tomato race, conjugating the recombinants into a strain of P. syringae pv. maculicola virulent on a tomato cultivar containing Pto, and screening for those clones that converted the normally virulent phenotype to avirulence. The cloned gene, designated avrPto, reduced multiplication of P. syringae pv. tomato transconjugants specifically on Pto tomato lines, as demonstrated by bacterial growth curve analyses. Analysis of F2 populations revealed cosegregation of resistance to P. syringae pv. tomato transconjugants carrying avrPto with resistance to P. syringae pv. tomato race 0. Surprisingly, mutation of avrPto in P. syringae pv. tomato race 0 does not eliminate the avirulent phenotype of race 0, suggesting that additional, as yet uncharacterized, avirulence genes and/or resistance genes may contribute to specificity in the avrPto- Pto interaction. Genetic analysis indicates that this resistance gene(s) would be tightly linked to Pto. Interestingly, P. syringae pv. glycinea transconjugants carrying avrPto elicit a typical hypersensitive resistant response in the soybean cultivar Centennial, suggesting conservation of Pto function between two crop plants, tomato and soybean. 35 NAL Call. No.: 442.8 Z34 Cloning and analysis of CUT1, a cutinase gene from Magnaporthe grisea. Sweigard, J.A.; Chumley, F.G.; Valent, B. Berlin, W. Ger. : Springer International; 1992 Mar. M G G : Molecular and general genetics v. 232 (2): p. 174-182; 1992 Mar. Includes references. Language: English Descriptors: Magnaporthe grisea; Genes; Esterases; Nucleotide sequences; Amino acid sequences; Introns; Enzyme activity; Genetic transformation; Cutin; Hydrolysis; Genetic code; Restriction mapping; Gene expression; Messenger RNA; Gene dosage Abstract: A gene from Magnaporthe grisea was cloned using a cDNA clone of the Colletotrichum gloeosporioides cutinase gene as a heterologous probe; the nucleotide sequence of a 2 kb DNA segment containing the gene has been determined. DNA hybridization analysis shows that the M. grisea genome contains only one copy of this gene. The predicted polypeptide contains 228 amino acids and is homologous to the three previously characterized cutinases, showing 74% amino acid similarity to the cutinase of C. gloeosporioides. Comparison with previously determined cutinase sequences suggests that the gene contains two introns, 115 and 147 bp in length. The gene is expressed when cutin is the sole carbon source but not when the carbon source is cutin and glucose together or glucose alone. Levels of intracellular and extracellular cutinase activity increase in response to growth in the presence of cutin. The activity level is higher in a transformant containing multiple copies of the cloned gene than in the parent strain. Non-denaturing polyacrylamide gels stained for esterase activity show a single major band among intracellular and extracellular proteins from cutin-grown cultures that is not present among intracellular and extracellular proteins prepared from glucose-grown or carbon- starved cultures. This band stains more intensely in extracts from the multicopy transformant than in extracts from the parent strain. We conclude that the cloned DNA contains a M. grisea gene for cutinase, which we have named CUT1. 36 NAL Call. No.: 448.3 J82 Cloning and characterization of a gene required for the secretion of extracellular enzymes across the outer membrane by Xanthomonas campestris pv. campestris. Hu, N.T.; Hung, M.N.; Chiou, S.J.; Tang, F.; Chiang, D.C.; Huang, H.Y.; Wu, C.Y. Washington, D.C. : American Society for Microbiology; 1992 Apr. Journal of bacteriology v. 174 (8): p. 2679-2687; 1992 Apr. Includes references. Language: English Descriptors: Xanthomonas campestris pv. campestris; Membranes; Secretion; Enzymes; Genes; Nucleotide sequences; Amino acid sequences; Cloning Abstract: Nonpathogenic mutants of Xanthomonas campestris pv. campestris, generated from transposon mutagenesis, accumulated extracellular polygalacturonate lyase, alpha-amylase, and endoglucanase in the periplasm. The transposon Tn5 was introduced by a mobilizable, suicidal plasmid, pSUP2021 or pEYDG1. Genomic banks of wild-type X. campestris pv. campestris, constructed on the broad-host-range, mobilizable cosmid pLAFRI or pLAFR3, were conjugated with one of the mutants, designated XC1708. Recombinant plasmids isolated by their ability to complement XC1708 can be classified into two categories. One, represented by pLASC3, can complement some mutants, whereas the other, represented by a single plasmid, pLAHH2, can complement all of the other mutants. Restriction mapping showed that the two recombinant plasmids shared an EcoRI fragment of 8.9 kb. Results from subcloning, deletion mapping, and mini-Mu insertional mutation of the 8.9-kb EcoRI fragment suggested that a 4.2-kb fragment was sufficient to complement the mutant XC1708. Sequence analysis of this 4.2-kb fragment revealed three consecutive open reading frames (ORFs), ORF1, ORF2, and ORF3. Hybridization experiments showed that Tn5 in the genome of XC1708 and other mutants complemented by pLASC3 was located in ORF3, which could code for a protein of 83.5 kDa. A signal peptidase 11 processing site was identified at the N terminus of the predicted amino acid sequence. Sequence homology of 51% was observed between the amino acid sequences predicted from ORF3 and the pulD gene of Klebsiella species. 37 NAL Call. No.: 448.3 J82 Cloning and characterization of pathogenicity genes from Xanthomonas campestris pv. glycines. Hwang, I.; Lim, S.M.; Shaw, P.D. Washington, D.C. : American Society for Microbiology; 1992 Mar. Journal of bacteriology v. 174 (6): p. 1923-1931; 1992 Mar. Includes references. Language: English Descriptors: Xanthomonas campestris pv. glycines; Genes; Mutants; Pathogenicity; Nucleotide sequences; Amino acid sequences Abstract: Nonpathogenic mutants of Xanthomonas campestris pv. glycines 8ra were generated with N-methyl-N-nitro-N'- nitrosoguanidine to identify and characterize pathogenicity genes of the bacterium. A total of 16 nonpathogenic mutants were isolated from 2,000 colonies. One mutant, NP1, was chosen for further study. NP1 did not multiply in soybean cotyledons. A genomic library of strain 8ra was constructed in the cosmid pLAFR3, and the cosmids were tested for complementation in NP1. One cosmid clone, pIH1, which contained a 31-kb insert, complemented mutant NP1. A restriction map of PIH1 was constructed, and deletion analyses identified a 10-kb HindIII fragment that restored pathogenicity to NP1. Southern hybridization analysis indicated that DNA sequences in the 10- kb HindIII fragment are conserved among other X. campestris pathovars tested. Three regions responsible for restoring pathogenicity have been identified by Tn3-HoHo1 mutagenesis. A 2.7-kb ClaI fragment was sequenced, and two possible open reading frames (ORF1 and ORF2) were found. Results indicated that ORF2 but not ORF1 may be expressed in Escherichia coli and in X. campestris pv. glycines. The carboxy terminus of the potential polypeptide encoded by ORF2 has an amino acid sequence similar to that of the gamma subunit of oxaloacetate decarboxylase, which is involved in sodium ion transport in Klebsiella pneumoniae. 38 NAL Call. No.: 448.3 AP5 Cloning and detection of chromosomal and extrachromosomal DNA from mycoplasmalike organisms that cause yellow dwarf disease of rice. Nakashima, K.; Kato, S.; Iwanami, S.; Murata, N. Washington, D.C. : American Society for Microbiology; 1991 Dec. Applied and environmental microbiology v. 57 (12): p. 3570-3575; 1991 Dec. Includes references. Language: English Descriptors: Oryza sativa; Mycoplasma-like organisms; Chromosomes; Dna; Dna probes; Disease vectors; Nephotettix cincticeps Abstract: DNA was extracted from rice plants infected with mycoplasmalike organisms (MLOs) causing yellow disease. DNA of the causal agent was separated from the host DNA by repeated bisbenzimide-CsCl equilibrium density gradient centrifugations. MLO DNA cut by HindIII was ligated into plasmid Bluescript II and cloned in Escherichia coli NM522. The DNA inserts were labeled with peroxidase and employed as probes in hybridization. Southern analysis revealed that the insert in pRYD-12 consisted of one, presumably chromosomal, piece of MLO DNA, whereas the insert in pRYD-19, another recombinant plasmid, consisted of one, presumably extrachromosomal, piece of MLO DNA. Cloned DNA probes were successfully applied in dot blot hybridization for the detection of rice yellow dwarf disease MLOs in rice plants and in an insect vector, the green rice leafhopper (Nephotettix cincticeps). 39 NAL Call. No.: QH426.C8 Cloning and expression of a chitinase gene from the hyperparasitic fungus Aphanocladium album. Blaiseau, P.L.; Kunz, C.; Grison, R.; Bertheau, Y.; Brygoo, Y. Berlin, W. Ger. : Springer International; 1992. Current genetics v. 21 (1): p. 61-66; 1992. Includes references. Language: English Descriptors: Deuteromycotina; Fungal antagonists; Fusarium oxysporum; Hyperparasitism; Genes; Chitinase; Recombinant DNA; Gene expression; Messenger RNA; Genetic transformation; Nucleotide sequences; Restriction mapping; Genetic regulation; Amino acid sequences Abstract: Recombinant clones from a cDNA library of an Aphanocladium album chitinase-overproducing mutant strain were isolated by screening with antiserum against a 39 kDa chitinase purified from this hyperparasitic fungus. Analysis of the isolated positive clones indicated that most of them carried the same cDNA. A cDNA from this group was used as a hybridization probe to isolate an 8 kb DNA fragment from a genomic library of the wild-type strain. The chitinase 1 gene was mapped to this fragment by two independent approaches. Its partial DNA sequence was in perfect agreement with an amino- terminal peptide sequence obtained by sequencing 23 amino acids of the 39 kDa chitinase. Its transfer in Fusarium oxysporum resulted in a transformant producing both a protein of about 39 kDa that cross-reacted with the chitinase antiserum and a chitinase activity that was inhibited by the same antiserum. Northern blot analysis indicates that the cloned chitinase gene was subject to catabolite repression and appeared inducible by chitin. 40 NAL Call. No.: 448.3 J82 Cloning and expression of the tabtoxin biosynthetic region from Pseudomonas syringae. Kinscherf, T.G.; Coleman, R.H.; Barta, T.M.; Willis, D.K. Washington, D.C. : American Society for Microbiology; 1991 Jul. Journal of bacteriology v. 173 (13): p. 4124-4132. ill; 1991 Jul. Includes references. Language: English Descriptors: Phaseolus vulgaris; Nicotiana tabacum; Pseudomonas syringae; Cloning; Bacterial toxins; Genes; Insertional mutagenesis; Mutants; Genetic transformation; Complementation; Cosmids; Pathogenicity; Deletions; Gene expression; Plant diseases; Disease resistance Abstract: Pseudomonas syringae BR2, a causal agent of bean wildfire, was subjected to Tn5 mutagenesis in an effort to isolate mutants unable to produce the beta-lactam antibiotic tabtoxin. Three of the tabtoxin-minus (Tox-) mutants generated appeared to have physically linked Tn5 insertions and retained their resistance to the active toxin form, tabtoxinine-beta- lactam (TbetaL). The wild-type DNA corresponding to the mutated region was cloned and found to restore the Tn5 mutants to toxin production. The use of cloned DNA from the region as hybridization probes revealed that the region is highly conserved among tabtoxin-producing pathovars of P. syringae and that the region deletes at a relatively high frequency (10(-3)/CFU) in BR2. The Tox-deletion mutants also lost resistance to tabtoxinine-beta-lactam. A cosmid designated pRTBL823 restored toxin production and resistance to BR2 deletion mutants. This cosmid also converted the tabtoxin- naive P. syringae epiphyte Cit7 to toxin production and resistance, indicating that pRTBL823 contains a complete set of biosynthetic and resistance genes. Tox- derivatives of BR2 did not produce disease symptoms on bean. Clones that restored toxin production to both insertion and deletion mutants also restored the ability to cause disease. However, tabtoxin- producing Cit7 derivatives remained nonpathogenic on bean and tobacco, suggesting that tabtoxin production alone is not sufficient to cause disease. 41 NAL Call. No.: 448.3 J82 Cloning and sequencing of an Agrobacterium tumefaciens beta- glucosidase gene involved in modifying a vir-inducing plant signal molecule. Castle, L.A.; Smith, K.D.; Morris, R.O. Washington, D.C. : American Society for Microbiology; 1992 Mar. Journal of bacteriology v 174 (5): p. 1478-1486; 1992 Mar. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Beta-glucosidase; Genes; Cloning; Nucleotide sequences; Amino acid sequences; Phenolic compounds; Enzyme activity; Cellobiose Abstract: Induction of Agrobacterium tumefaciens virulence genes by plant phenolic compounds is essential for successful T-DNA transfer to a host plant. In Douglas fir needles, the major virulence region inducer is the glycoside coniferin (J.W. Morris and R.O. Morris, Proc. Natl. Acad. Sci. USA 87:3612-3618, 1990). Agrobacterium strains with high beta- glucosidase activity respond to coniferin and infect Douglas fir seedlings, whereas most strains with low beta-glucosidase activity fail to respond to coniferin and are avirulent on this host. We have cloned two beta-glucosidase genes from A. tumefaciens B3/73 and sequenced one of them, cbg1. It appears to be part of a polycistronic unit and shows a high bias for GC-rich codons. When expressed in Escherichia coli, Cbg1 beta- glucosidase hydrolyzes coniferin but not cellobiose. The 88- kDa predicted product of cbg1 is highly similar to one other bacterial beta-glucosidase and several fungal beta- glucosidases. There is little homology between Cbg1 and other bacterial beta-glucosidases, including an Agrobacterium cellobiase. 42 NAL Call. No.: SB732.6.M65 Cloning of a melanin biosynthetic gene essential for appressorial penetration of Colletotrichum lagenarium. Kubo, Y.; Nakamura, H.; Kobayashi, K.; Okuno, T.; Furusawa, I. St. Paul, Minn. : APS Press; 1991 Sep. Molecular plant-microbe interactions : MPMI v. 4 (5): p. 440-445; 1991 Sep. Includes references. Language: English Descriptors: Cucumis sativus; Colletotrichum orbiculare; Colonizing ability; Appressoria; Infection; Cell walls; Penetration; Pathogenicity; Melanins; Biosynthesis; Genes; Mutants; Strains; Albinos; Cloning; Genetic analysis; Genetic transformation 43 NAL Call. No.: QH426.C8 Cloning the REC1 gene of Ustilago maydis. Holden, D.W.; Spanos, A.; Kanuga, N.; Banks, G.R. Berlin, W. Ger. : Springer International; 1991. Current genetics v. 20 (1/2): p. 145-150; 1991. Includes references. Language: English Descriptors: Ustilago zeae; Genes; Cloning; Homologous recombination; Dna repair; Ultraviolet radiation; Susceptibility; Induced mutations; Insertional mutagenesis; Complementation; Alleles Abstract: The REC1 gene of Ustilago maydis plays a key role in homologous recombination and the repair of damaged DNA. In order to understand the nature and functions of the gene product, the gene has been cloned by functional complementation. A 3.8 kb cloned fragment complements the pleiotropic mitotic phenotype of different rec1 alleles. It does not complement the UV sensitivity of two other sensitive mutants. Disruption of the chromosomal copy of the 1.566 kb open reading frame within this fragment reproduces the rec1 pleiotropic phenotype. Furthermore, in diploids this disrupted reading frame is unable to complement previously characterised rec1 alleles. 44 NAL Call. No.: 500 N21P Components of the protein-excretion apparatus of Pseudomonas aeruginosa are processed by the type IV prepilin peptidase. Nunn, D.N.; Lory, S. Washington, D.C. : The Academy; 1992 Jan01. Proceedings of the National Academy of Sciences of the United States of America v. 89 (1): p. 47-51; 1992 Jan01. Includes references. Language: English Descriptors: Pseudomonas aeruginosa; Mutants; Nucleotide sequences; Peptides; Proteins; Amino acid sequences; Excretion Abstract: In the Gram-negative pathogen Pseudomonas aeruginosa, mutants in the gene for the prepilin peptidase (pilD) are pleiotropic, as they not only fail to process pilin but also accumulate in the periplasm, in their mature form, several toxins and hydrolytic enzymes that are normally exported to the external medium (excreted). We have suggested that this excretion defect is due to the lack of PilD- dependent processing of proteins that share sequences in common with the prepilin subunit and that are components of a protein-excretion machinery. In this paper we report the isolation and characterization of transposon-induced excretion mutants with phenotypes similar to that of a pilD gene mutant. Using oligonucleotide probes designed to recognize sequences encoding the cleavage site of the type IV prepilins, we have isolated four linked genes with the predicted putative PilD- dependent cleavage site. Site-specific mutations within these genes have shown that they are required for protein excretion, and PilD-dependent processing of at least one of the four encoded proteins was demonstrated. Evidence suggests that similar components play a role in protein excretion in a wide variety of Gram-negative bacteria. 45 NAL Call. No.: 470 SCI2 Conjugative transfer by the virulence system of Agrobacterium tumefaciens. Beijersbergen, A.; Dulk-Ras, A. den; Schilperoort, R.A.; Hooykaas, P.J.J. Washington, D.C. : American Association for the Advancement of Science; 1992 May29. Science v. 256 (5061): p. 1324-1327; 1992 May29. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Dna; Gene transfer; Plasmids; Tumors Abstract: Agrobacterium tumefaciens transfers part of its Ti plasmid, the transferred DNA (T-DNA), to plant cells during tumor induction. Expression of this T-DNA in plant cells results in their transformation into tumor cells. There are similarities between the process of T-DNA transfer to plants and the process of bacterial conjugation. Here, the T-DNA transfer machinery mediated conjugation between bacteria. Thus, products of the Vir region of the Ti plasmid of Agrobacterium tumefaciens, normally involved in transfer of DNA from bacteria to plants, can direct the conjugative transfer of an IncQ plasmid between agrobacteria. 46 NAL Call. No.: 448.3 AP5 Conservation of plasmid DNA sequences in coronatine-producing pathovars of Pseudomonas syringae. Bender, C.L.; Young, S.A.; Mitchell, R.E. Washington, D.C. : American Society for Microbiology; 1991 Apr. Applied and environmental microbiology v. 57 (4): p. 993-999; 1991 Apr. Includes references. Language: English Descriptors: Pseudomonas syringae pv. tomato; Pseudomonas syringae pv. atropurpurea; Pseudomonas syringae pv. glycinea; Pseudomonas syringae pv. morsprunorum; Plasmids; Dna hybridization; Genes; Bacterial toxins; Biosynthesis; Induced mutations; Restriction mapping; Phytotoxicity; Bioassays; Crops Abstract: In Pseudomonas syringae pv. tomato PT23.2, plasmid pPT23A (101 kb) is involved in synthesis of the phytotoxin coronatine (C. L. Bender, D. K. Malvick, and R. E. Mitchell, J. Bacteriol. 171:807-812, 1989). The physical characterization of mutations that abolished coronatine production indicated that at least 30 kb of pPT23A DNA are required for toxin synthesis. In the present study, 32P- labeled DNA fragments from the 30-kb region of pPT23A hybridized to plasmid DNAs from several coronatine-producing pathovars of P. syringae under conditions of high stringency. These experiments indicated that this region of pPT23A was strongly conserved in large plasmids (90 to 105 kb) that reside in P. syringae pv. atropurpurea, glycinea, and morsprunorum. The functional significance of the observed homology was demonstrated in marker-exchange experiments in which Tn5-inactivated sequences from the 30-kb region of pPT23A were used to mutate coronatine synthesis genes in the three heterologous pathovars. Physical characterization of the Tn5 insertions generated by marker exchange indicated that genes controlling coronatine synthesis in P. syringae pv. atropurpurea 1304, glycinea 4180, and morsprunorum 567 and 3714 were located on the large indigenous plasmids where homology was originally detected. Therefore, coronatine biosynthesis genes are strongly conserved in the plasmid DNAs of four producing pathovars, despite their disparate origins (California, Japan, New Zealand, Great Britain, and Italy). 47 NAL Call. No.: 448.3 J82 Conservation of the gene for outer membrane protein OprF in the family Pseudomonadaceae: sequence of the Pseudomonas syringae oprF gene. Ullstrom, C.A.; Siehnel, R.; Woodruff, W.; Steinbach, S.; Hancock, R.E.W. Washington, D.C. : American Society for Microbiology; 1991 Jan. Journal of bacteriology v. 173 (2): p. 768-775; 1991 Jan. Includes references. Language: English Descriptors: Pseudomonas syringae; Genes; Membranes; Proteins; Nucleotide sequences; Amino acid sequences Abstract: The conservation of the oprF gene for the major outer membrane protein OprF was determined by restriction mapping and Southern blot hybridization with the Pseudomonas aeruginosa oprF gene as a probe. The restriction map was highly conserved among 16 of the 17 serotype type strains and 42 clinical isolates of P. aeruginosa. Only the serotype 12 isolate and one clinical isolate showed small differences in restriction pattern. Southern probing of PstI chromosomal digests of 14 species from the family Pseudomonadaceae revealed that only the nine members of rRNA homology group I hybridized with the oprF gene. To reveal the actual extent of homology, the oprF gene and its product were characterized in Pseudomonas syringae. Nine strains of P. syringae from seven different pathovars hybridized with the P. aeruginosa gene to produce five different but related restriction maps. All produced an OprF protein in their outer membranes with the same apparent molecular weight as that of P. aeruginosa OprF. In each case the protein reacted with monoclonal antibody MA4-10 and was similarly heat and 2-mercaptoethanol modifiable. The purified OprF protein of the type strain P. syringae pv. syringae ATCC 19310 reconstituted small channels in lipid bilayer membranes. The oprF gene from this latter strain was cloned and sequenced. Despite the low level of DNA hybridization between P. aeruginosa and P. syringae DNA, the OprF gene was highly conserved between the species with 72% DNA sequence identity and 68% amino acid sequence identity overall. The carboxy terminus-encoding region of P. syringae oprF showed 85 and 33% identity, respectively, with the same regions of the P. aeruginosa oprF and Escherichia coli ompA genes. 48 NAL Call. No.: 448.3 J82 Constitutive mutations of Agrobacterium tumefaciens transcriptional activator virG. Pazour, G.J.; Ta, C.N.; Das, A. Washington, D.C. : American Society for Microbiology; 1992 Jun. Journal of bacteriology v. 174 (12): p. 4169-4174; 1992 Jun. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Mutations; Genes; Virulence; Gene expression Abstract: The virulence (vir) genes of Agrobacterium tumefaciens Ti plasmids are positively regulated by virG in conjunction with virA and plant-derived inducing molecules. A procedure that utilizes both genetic selection and a genetic screen was developed to isolate mutations in virG that led to elevated levels of vir gene expression in the absence of virA and plant phenolic inducers. Mutants were isolated at a frequency of 1 in 10(7) to 10(8). Substitution mutations at two positions in the virG coding region were found to result in the desired phenotype. One mutant had an asparagine-to- aspartic acid substitution at residue 54, and the other contained an isoleucine-to-leucine substitution at residue 106. In both cases, the mutant phenotype required the presence of the active-site aspartic acid residue at position 52. Further analysis showed that no other substitution at residue 54 resulted in a constitutive phenotype. In contrast, several substitutions at residue 106 led to a constitutive phenotype. The possible roles of the residues at positions 54 and 106 in VirG function are discussed. 49 NAL Call. No.: 448.3 J82 Controlled expression of the transcriptional activator gene virG in Agrobacterium tumefaciens by using the Escherichia coli lac promoter. Chen, C.Y.; Winans, S.C. Washington, D.C. : American Society for Microbiology; 1991 Feb. Journal of bacteriology v. 173 (3): p. 1139-1144; 1991 Feb. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Genes; Gene expression; Induction; Ph Abstract: The Agrobacterium VirG protein is normally expressed from two promoters in response to multiple stimuli, including plant-released phenolics (at promoter P1) and acidic growth media (at promoter P2). To simplify the analysis of vir gene induction, we sought to create Agrobacterium strains in which virG could be expressed in a controllable fashion. To study the possibility of using the lac promoter and repressor, we constructed a plasmid containing the lac promoter fused to the lacZ structural gene. A derivative of this plasmid containing the lacIq gene was also constructed. The plasmid not containing lacIq expressed high levels of beta- galactosidase. The plasmid containing lacIq expressed beta- galactosidase at very low levels in the absence of o- nitrophenyl-beta-D-galactosidase (IPTG) and at moderate levels in the presence of IPTG. We also fused the lac promoter to a virG::lacZ translational fusion and found that IPTG elevated expression of this translational fusion to moderate levels, though not to levels as high as from the stronger of the two native virG promoters. Finally, the lac promoter was used to express the native virG gene in strains containing a virB::lacZ translational fusion. virB expression in this strain depended on addition of IPTG as well as the vir gene inducer acetosyringone. In a similar strain lacking lacIq, virB expression was greater than in a strain in which virG was expressed from its native promoters. Expression of virG from the lac promoter did not alter the acidic pH optimum for vir gene induction, indicating that the previously observed requirement for acidic media was not due solely to the need to induce P2. 50 NAL Call. No.: 1.9 P69P Copper and streptomycin-resistance strains and host differentiated races of Xanthomonas campestris pv. vesicatoria in North Carolina. Ritchie, D.F.; Dittapongpitch, V. St. Paul, Minn. : American Phytopathological Society; 1991 Jul. Plant disease v. 75 (7): p. 733-736; 1991 Jul. Includes references. Language: English Descriptors: North Carolina; Capsicum annuum; Lycopersicon esculentum; Xanthomonas campestris pv. vesicatoria; Strains; Races; Strain differences; Plant diseases; Phenotypes; Virulence; Copper; Streptomycin; Resistance; Correlation; Plasmids; Pest resistance 51 NAL Call. No.: QR1.F44 Cross-blot: a rapid screening procedure for determining specificity of antibodies to native proteins of the brown-rot fungus Postia placenta. Clausen, C.A.; Green, F. III; Highley, T.L. Amsterdam : Elsevier Science Publishers; 1991 Mar01. FEMS microbiology letters - Federation of European Microbiological Societies v. 78 (2/3): p. 315-318; 1991 Mar01. Includes references. Language: English Descriptors: Wood destroying fungi; Fungal antigens; Monoclonal antibodies; Screening; Immunoblotting; Rapid methods Abstract: A method is described for rapidly screening large numbers of mono-or polyclonal antibodies for specificity with an equivalent number of antigens on a single sheet of nitrocellulose paper. This method, referred to as cross-blot, uses only 120 microliter of antigen or antibody and can be completed in less than 6 h. Cross-blot was developed for rapid screening of hybridoma culture supernatants and can be adapted for use with Western blots of native and denatured proteins as well as screening polyclonal antibodies. In this study, murine monoclonal antibodies were produced to Postia placenta, a brown-rot wood decay fungus. Immunizing antigens were derived from P. placenta-decayed wood extracts. The antibodies were screened for specificity to a number of native proteins produced by the fungus. Cross-blot proved to an efficient method of visualizing cross-reacting antibodies while screening large numbers of antibodies for specificity. 52 NAL Call. No.: 442.8 Z34 Cross-talk between the virulence and phosphate regulons of Agrobacterium tumefaciens caused by an unusual interaction of the transcriptional activator with a regulatory DNA element. Aoyama, T.; Takanami, M.; Makino, K.; Oka, A. Berlin, W. Ger. : Springer International; 1991 Jul. M G G : Molecular and general genetics v. 227 (3): p. 385-390; 1991 Jul. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Escherichia coli; Transcription; Virulence; Genes; Plasmids; Gene expression; Dna; Nucleotide sequences; Binding site; Dna binding proteins; Genetic regulation; Promoters; Controlling elements; Phosphates; Nutrient deficiencies; Bacterial proteins Abstract: Transcription of a virulence gene on the hairyroot- inducing plasmid A4, which is induced by plant factors in Agrobacterium tumefaciens, was also activated by phosphate limitation in both A. tumefaciens and Escherichia coli. The starting site of RNA synthesized under the two inducing conditions was the same, and an identical promoter was responsible for both inducible expressions. The response of the virulence gene to phosphate limitation did not require the positive regulator VirG for the virulence regulon, but depended entirely on the presence of PhoB protein, the positive regulator for the phosphate regulon. The DNA signal upstream of the virulence gene, which is targeted by the VirG protein, was recognized by the E. coli PhoB protein in vitro. These results indicate that cross-talk between the two regulons occurred during the recognition of a DNA signal by the regulatory protein. 53 NAL Call. No.: QK725.P54 Crown gall transformation of lentil (Lens culinaris Medik.) with virulent strains of Agrobacterium tumefaciens. Warkentin, T.D.; McHughen, A. Berlin, W. Ger. : Springer International; 1991. Plant cell reports v. 10 (10): p. 489-493; 1991. Includes references. Language: English Descriptors: Lens culinaris; Agrobacterium tumefaciens; Genetic transformation; Virulence; Strain differences; Tumors Abstract: Four diverse strains of agrobacterium tumefaciens (C58, Ach5, GV3111, and A281) were capable of inducing tumors at a high frequency on inoculated stems of lentil (Lens culinaris Medik. cultivar Laird) in vivo, and on excised shoot apices in vitro. GV3111 and Ach5 produced the largest and heaviest tumors in vivo, while A281 produced the heaviest tumors in vitro. Tumor formation and opine production are indicative of plant cell transformation and tumors produced appropriate opines: nopaline (C58), octopine (Ach5 and GV3111), and agropine and mannopine (A281). Southern analysis of DNA from a tumor line produced by strain C58 showed that a T-DNA fragment had been transferred into the lentil genome. 54 NAL Call. No.: SB599.P45 Cultivar-strain specificity between Chrysanthemum morifolium and Agrobacterium tumefaciens. Bush, A.L.; Pueppke, S.G. London : Academic Press; 1991 Oct. Physiological and molecular plant pathology v. 39 (4): p. 309-323; 1991 Oct. Includes references. Language: English Descriptors: Dendranthema morifolium; Cultivars; Agrobacterium tumefaciens; Strains; Host specificity; Molecular biology; Strain differences; Pathogenicity; Varietal susceptibility; Tumors; Marker genes; Beta-glucuronidase; Enzyme activity; Gene expression; Gene transfer; Genetic transformation; Endogenous growth regulators Abstract: We have examined cultivar specificity between Chrysanthemum morifolium and Agrobacterium tumefaciens strains Chry5 and B6. Although 42% of the 85 cultivars formed tumours after inoculation with both strains, some cultivars formed no tumours in response to Chry5, to B6, or to both strains. Four cultivars were utilized to examine these interactions in a leaf disc transformation system with a virE::lacZ fusion. We specifically tested the hypothesis that cultivar-strain specificity is due to differential vir gene induction by conditioned media from the cultivars, but could find no evidence to support this possibility. We also tested the hypothesis that specificity is due to differential T-DNA transfer, integration or expression. This was accomplished by transferring into each strain a scorable marker (beta- glucuronidase) contained between T-DNA borders. Leaf discs then were inoculated, and expression of enzyme activity was used to monitor transformation. Transfer of the T-DNA marker gene followed a pattern that reflected tumorigenicity in all cultivar-strain pairs, indicating that cultivar-strain specificity was due to differences in the transfer of T-DNA, or in subsequent integration processes. Analysis of the auxin and cytokinin levels of cultivars representative of different cultivar-strain interactions suggested that, although high hormone levels may be associated with high tumour mass, they do not appear to account for the innate susceptibility of a cultivar. 55 NAL Call. No.: QH345.A1P73 Culture of Datura innoxia Mill transformed roots as a producer of tropane alkaloids. Bulgakov, V.P.; Zhuravlev, Yu.N.; Toroptseva, I.V. New York, N.Y. : Consultants Bureau; 1991 Sep. Applied biochemistry and microbiology v. 27 (2): p. 222-226. ill; 1991 Sep. Translated from: Prikladnaia Biokhimiia i Mikrobiologiia, v. 27 (2), 1991, p. 286-291. (385 P93). Includes references. Language: English; Russian Descriptors: Datura fastuosa; Agrobacterium rhizogenes; Cell culture; Genetic transformation; Tumors; Roots; Tropane alkaloids; Biosynthesis; Growth 56 NAL Call. No.: aTP375.T4 Current productivity and future opportunities for sugarcane agriculture from a plant breeder's perspective. Heinz, D.J. New Orleans : Sugar Processing Research Inc; 1991 May. Proceedings of the ... sugar processing research conference. p. 212-228; 1991 May. Meeting held on May 29-June 1, 1990, San Francisco, California. Includes references. Language: English Descriptors: Saccharum officinarum; Saccharum; Crop production; Crop yield; Cane sugar; Plant breeding; Cultivars; Biotechnology; Genetic engineering; Plant diseases; Genetic resistance 57 NAL Call. No.: QL391.N4J62 Current status of the availability, development, and use of host plant resistance to nematodes. Roberts, P.A. Lake Alfred, Fla. : Society of Nematologists; 1992 Jun. Journal of nematology v. 24 (2): p. 213-227; 1992 Jun. Literature review. Includes references. Language: English Descriptors: Plant parasitic nematodes; Pest resistance; Plant breeding; Genes; Inheritance; Screening; Tolerance; Literature reviews Abstract: Host plant resistance (HPR) to nematodes has been identified in many major crops and related wild germplasm. Most HPR is to the more specialized, sedentary endoparasitic genera and species, e.g., Globodera, Heterodera, Meloidogyne, Nacobbus, Rotylenchulus, and Tylenchulus. Some HPR has been developed or identified also to certain migratory endoparasites (Aphelenchoides, Ditylenchus, Pratylenchus, Radopholus) in a few hosts. Commercial use of HPR remains limited, despite its benefits to crop production when deployed appropriately. Restricted use and availability of HPR result from problems associated with transfer of resistance into acceptable cultivars. Difficulties occur in gene transfer to acceptable cultivars because of incompatibility barriers to hybridization or linkage to undesirable traits, for example in cucurbitaceous and solanaceous crops and sugarbeet. Specificity of HPR to only one species, or one or few pathotypes, as it relates to resistance durability and nematode virulence, and HPR response to abiotic factors such as high soil temperature, also limit availability and utility. A scheme for HPR development is presented to emphasize nematology research and information requirements for expanding HPR use in nematode control programs, for example in common bean, sugarbeet, and tomato. Nonbiological factors that influence HPR usage are discussed, including heavy reliance on nematicide programs, low priority of nematode HPR in many breeding programs, and insufficient breeder-nematologist collaboration. 58 NAL Call. No.: QK725.P532 Cutinase is not required for fungal pathogenicity on pea. Stahl, D.J.; Schafer, W. Rockville, Md. : American Society of Plant Physiologists; 1992 Jun. The Plant cell v. 4 (6): p. 621-629; 1992 Jun. Includes references. Language: English Descriptors: Pisum sativum; Nectria haematococca; Fusarium solani f.sp. pisi; Fungal diseases; Pathogenicity; Esterases; Structural genes; Induced mutations; Mutants; Enzyme deficiencies; Virulence; Genetic transformation; Enzyme activity Abstract: Cutinase, a fungal extracellular esterase, has been proposed to be crucial in the early events of plant infection by many pathogenic fungi. To test the long-standing hypothesis that cutinase of Nectria haematococca (Fusarium solani f sp pisi) is essential to pathogenicity, we constructed cutinase- deficient mutants by transformation-mediated gene disruption of the single cutinase gene of a highly virulent N. haematococca strain. Four independent mutants were obtained lacking a functional cutinase gene, as confirmed by gel blot analyses and enzyme assays. Bioassays of the cutinase- deficient strains showed no difference in pathogenicity and virulence on pea compared to the wild type and a control transformant. We conclude that the cutinase of N. haematococca is not essential for the infection of pea. 59 NAL Call. No.: 64.8 C883 Cyclic breeding used to incorporate kernel discoloration resistance into malting barley. Gebhardt, D.J.; Rasmusson, D.C.; Wilcoxson, R.D. Madison, Wis. : Crop Science Society of America; 1992 Mar. Crop science v. 32 (2): p. 352-356; 1992 Mar. Includes references. Language: English Descriptors: Hordeum vulgare; Plant breeding; Kernels; Discoloration; Disease resistance; Fungal diseases; Malting quality; Selection criteria; Inheritance; Agronomic characteristics; Recurrent selection; Quantitative traits; Genetic improvement; Cochliobolus sativus; Alternaria alternata; Gibberella zeae Abstract: Obtaining kernel discoloration (KD) resistance in malting barley (Hordeum vulgare L.) is an important breeding objective in the midwestern USA. This study was undertaken to evaluate a cyclic breeding procedure for transferring quantitative KD resistance across a wide genetic gap, and to obtain parental germplasm or a new cultivar having KD resistance combined with good agronomic performance and malting quality. Six cycles of crossing and selection were done beginning in 1970 to incorporate KD resistance genes from 'Chevron' and CI 9539 into Minnesota barley lines. Chevron and CI 9539 were inferior for both agronomic and quality traits. Subsequently, 45 sixth-cycle derived lines were evaluated in inoculated disease nurseries and in field trials to determine whether resistance was transferred and to assess agronomic and malting quality merit. Kernel discoloration resistance was successfully transferred using the cyclic breeding procedure, although the resistance level tended to be below that of the resistance sources. The derived lines were similar to the local cultivars Robust and Morex for agronomic and quality traits, except for kernel plumpness, and to a lesser degree malt extract. They showed marked overall improvement compared with the resistance sources, Chevron and CI 9534, and a few of the lines merit consideration as potential cultivars. Unconscious selection was hypothesized to account for the intermediate level of KD resistance observed in local germplasm. In this situation, cyclic recurrent breeding appeared to be a good choice for incorporating a quantitative disease trait into a good genetic background. 60 NAL Call. No.: QK710.P62 Cytosolic localization in transgenic plants of the rolC peptide from Agrobacterium rhizogenes. Estruch, J.J.; Parets-Soler, A.; Schmulling, T.; Spena, A. Dordrecht : Kluwer Academic Publishers; 1991 Sep. Plant molecular biology : an international journal on molecular biology, biochemistry and genetic engineering v. 17 (3): p. 547-550; 1991 Sep. Includes references. Language: English Descriptors: Nicotiana tabacum; Agrobacterium rhizogenes; Genes; Bacterial proteins; Immunocytochemistry; Cytosol; Leaves; Transgenics; Genetic transformation; Pathogenesis; Plant diseases; Morphogenesis Abstract: The rolC gene of Agrobacterium rhizogenes codes for a peptide with an apparent molecular weight of approximately 20 kDa. Immunolocalization of the rolC peptide, in leaves of transgenic plants which are genetic mosaics for the expression of the rolC gene, is restricted to the phenotypically altered sectors. Subcellular fractionation of homogenates from 35S- rolC transgenic leaves shows the cytosolic localization of the rolC peptide. 61 NAL Call. No.: 464.8 P56 Detection and identification of Peronosclerospora sacchari in maize by DNA hybridization. Yao, C.L.; Magill, C.W.; Frederiksen, R.A.; Bonde, M.R.; Wang, Y.; Wu, P.S. St. Paul, Minn. : American Phytopathological Society; 1991 Aug. Phytopathology v. 81 (8): p. 901-905; 1991 Aug. Includes references. Language: English Descriptors: Zea mays; Peronosclerospora sacchari; Mildews; Seedborne fungi; Dna hybridization; Dna probes; Southern blotting; Detection; Identification; Seeds; Infections; Restriction mapping; Restriction fragment length polymorphism; Chemotaxonomy Abstract: The causal organism of an incidence of maize downy mildew in Southern China proved difficult to classify by standard techniques. The pathogen, subsequently identified as Peronosclerospora sacchari, was detected by DNA hybridization in endosperm, pericarp, and pedicel tissues, but not in embryos of infected maize seeds. Plasmid pCLY83, which had been selected from a P. maydis DNA library, served as the probe. No evidence for hybridization was detected between the probe and DNAs extracted from ten common seedborne fungi of maize: Colletotrichum graminicola, Acremonium strictum, Curvularia lunata, Fusarium moniliforme, Bipolaris maydis, Macrophomina phaseolina, Rhizoctonia sp., Rhizopus sp., Penicillium sp., and Alternaria sp. Hybridization was also not detected with DNAs isolated from plant tissues infected with Sclerospora graminicola or Sclerophthora macrospora. The hybridizing DNA of the corn pathogen from China was readily distinguished from P. sorghi and P. maydis by differences in EcoRI, PvuI, BamHI and HindIII restriction patterns. RFLP patterns on blots of DNA from the plants showing symptoms of downy mildew in this case were the same as those for P. philippinensis and P. sacchari, now believed to be conspecific. 62 NAL Call. No.: QR1.C78 Detection of several strains of the bacterium-like organism of citrus greening disease by DNA probes. Villechanoux, S.; Garnier, M.; Renaudin, J.; Bove, J.M. New York, N.Y. : Springer International; 1992 Feb. Current microbiology v. 24 (2): p. 89-95; 1992 Feb. Includes references. Language: English Descriptors: India; Thailand; Philippines; Indonesia; China; Taiwan; South Africa; Citrus sinensis; Catharanthus roseus; Citrus greening; Plant pathogens; Strains; Phloem; Dna; Dna probes; Diagnostic techniques Abstract: Greening disease of citrus is caused by a phloem- restricted, bacterium-like organism (BLO). DNA was purified from phloem tissue of periwinkle plants infected with an Indian strain of the greening BLO, restricted with HindIII endonuclease, and cloned in the replicative form of bacteriophage M13mpl8. By differential hybridizations involving DNA from healthy and infected periwinkle plants, we have selected three recombinant phages containing BLO DNA. The BLO DNA inserts (In-2.6, In-1.9, and In-0.6) have been purified from the viral replicative forms and used as probes. Southern and dot hybridizations have shown that In-2.6 and In-1.9 recognized all asian strains tested (strains from India, Thailand. the Philippines, Indonesia, China, and Taiwan), but-not a South African strain. In-0.6 reacted only with the indian BLO strain. 63 NAL Call. No.: 448.39 SO12 The development and use of monoclonal antibodies for detection of Erwinia. Vernon-Shirley, M.; Burns, R. Oxford : Blackwell Scientific Publications; 1992 Feb. The Journal of applied bacteriology v. 72 (2): p. 97-102; 1992 Feb. Includes references. Language: English Descriptors: Erwinia carotovora subsp. atroseptica; Erwinia carotovora subsp. carotovora; Serotypes; Plant diseases; Bacterial antigens; Monoclonal antibodies; Elisa; Diagnostic techniques Abstract: Three monoclonal antibodies (McAb), which reacted specifically with Erwinia carotovora, were produced. Monoclonal antibody 14/18.6 reacted with serogroup I/3390 but not with two other serogroups of E.c. subsp. atroseptica nor with 31 serogroups of E.c. subsp. carotovora; McAb 14/2 reacted with all 34 serogroups; and McAb 14/8.6 was as sensitive as a commercially produced polyclonal antiserum in detecting E.c. subsp. atroseptica by enzyme-linked immunosorbent assay. 64 NAL Call. No.: 464.8 P56 Development of an immunosorbent assay for seedborne Erwinia stewartii in corn seeds. Lamka, G.L.; Hill, J.H.; McGee, D.C.; Braun, E.J. St. Paul, Minn. : American Phytopathological Society; 1991 Aug. Phytopathology v. 81 (8): p. 839-846; 1991 Aug. Includes references. Language: English Descriptors: Zea mays; Erwinia stewartii; Seeds; Infections; Elisa; Wilts; Strains; Antibodies; Monoclonal antibodies; Seedborne organisms; Pathogenicity Abstract: Specificity of polyclonal and monoclonal antibodies generated to Erwinia stewartii was determined by testing 167 bacterial strains in enzyme-linked immunosorbent assay (ELISA). Of these, the antibodies were positive to all 43 E. stewartii strains tested. Reaction of the monoclonal antibody to all other bacterial strains was negative. However, the polyclonal antibodies reacted with seven of 105 nonpathogenic bacteria from corn plants and seeds determined not to be virulent E. stewartii. A double-sandwich ELISA that used the polyclonal and monoclonal antibodies was developed to detect E. stewartii in ground corn-seed samples. A comparison of four ELISA procedures to detect E. stewartii in pure culture and mixed with corn-seed tissue revealed that the most appropriate procedure was a double-sandwich ELISA using polyclonal antibodies for capture and monoclonal antibodies for detection. The assay detected E. stewartii antigen in seeds from plants inoculated with a rifampicin and nalidixic acid tolerant strain of E. stewartii but not in seeds from uninoculated plants. The presence of viable E. stewartii in seeds from inoculated plants was confirmed by culture. Analyses of 400 single seeds showed an absolute positive correlation between recovery of bacteria and ELISA response in eight seeds. E. stewartii was recovered from 10 other seeds that had a negative ELISA response. Recovered bacterial populations in nine of these 10 seeds were below the threshold of detection by ELISA. 65 NAL Call. No.: SB950.3.A8P535 Development of Australian passionfruit hybrids to improve quality and disease tolerance. Fitzell, R.D.; Peak, C.M.; Peasley, D.; Cox, G. Victoria : R.G. Richardson; 1991. Plant protection quarterly v. 6 (2): p. 65-67; 1991. Includes references. Language: English Descriptors: Australia; Passiflora edulis; Plant breeding; Commercial hybrids; Hybridization; Selection criteria; Disease resistance; Genetic resistance; Alternaria alternata; Crop quality; Fruits; Size; Vigor; Flavor 66 NAL Call. No.: QK725.P532 Developmental and pathogen-induced activation of the Arabidopsis acidic chitinase promoter. Samac, D.A.; Shah, D.M. Rockville, Md. : American Society of Plant Physiologists; 1991 Oct. The Plant cell v. 3 (10): p. 1063-1072; 1991 Oct. Includes references. Language: English Descriptors: Arabidopsis thaliana; Lycopersicon esculentum; Alternaria solani; Phytophthora infestans; Chitinase; Promoters; Beta-glucuronidase; Reporter genes; Chimeras; Gene expression; Leaves; Infections; Histoenzymology; Transgenics; Genetic transformation; Ethylene; Salicylic acid; Roots Abstract: Expression of the Arabidopsis acidic chitinase promoter was investigated during plant development and in response to inoculation with fungal pathogens. A chimeric gene composed of 1129 bp of 5' upstream sequence from the acidic chitinase gene was fused to the beta-glucuronidase (GUS) coding region and used to transform Arabidopsis and tomato. Promoter activity was monitored by histochemical and quantitative assays of GUS activity. In healthy transgenic plants, the acidic chitinase promoter activity was restricted to roots, leaf vascular tissue, hydathodes, guard cells, and anthers, whereas GUS expression was induced in mesophyll cells surrounding lesions caused by Rhizoctonia solani infection of transgenic Arabidopsis. In transgenic tomato plants, GUS expression was induced around necrotic lesions caused by Alternaria solani and Phytophthora infestans. Expression of the acidic chitinase promoter-GUS transgene was weakly induced by infiltrating leaves with salicylic acid. Analysis of a series of 5' deletions of the acidic chitinase promoter in Arabidopsis indicated that the proximal 192 bp from the transcription initiation site was sufficient to establish both the constitutive and induced pattern of expression. Elements further upstream were involved in quantitative expression of the gene. The location of a negative regulatory element was indicated between -384 and -590 and positive regulatory elements between -1129 and-590. 67 NAL Call. No.: 442.8 D49 Developmental profiles of epidermal mRNAs during the pupal- adult molt of Tenebrio molitor and isolation of a cDNA clone encoding an adult cuticular protein: effects of juvenile hormone analogue. Bouhin, H.; Charles, J.P.; Quennedey, B.; Delachambre, J. Orlando, Fla. : Academic Press; 1992 Jan. Developmental biology v. 149 (1): p. 112-122; 1992 Jan. Includes references. Language: English Descriptors: Tenebrio molitor; Pupae; Adults; Cuticle; Proteins; Protein synthesis; Translation; Messenger RNA; Juvenile hormone analogs; Gene expression; Metamorphosis; Ecdysis; Immunocytochemistry Abstract: Changes in translatable mRNAs from the wing epidermis of the Coleoptera Tenebrio molitor have been investigated during metamorphosis by analysis of in vitro translated products. Striking differences between the patterns obtained from mRNAs extracted during pupal and adult cuticle secretion indicated that a drastic change in gene expression occurs during the pupal-adult transition. In addition to these stage-specific modifications, the mRNA patterns changed within each cuticular synthesis program (pupal or adult), especially at ecdysis. After tritiated leucine incorporation, some of the major radiolabeled cuticular proteins showed similar changes suggesting that the sequential appearance of mRNAs corresponds to sequential deposition of cuticular proteins. In supernumerary pupae obtained after juvenile hormone analogue (JHA) application on newly ecdysed pupae, translatable mRNA were very similar to those of pharate pupae. The JHA seemed, therefore, to prevent the expression of the adult program. By immunoblotting in vitro translated products with a monoclonal antibody recognizing an adult-specific cuticular protein, the developmental profile of the corresponding mRNA was studied. This mRNA was detected in anterior wing epidermis during the first 80 hr of the pharate adult stage. Using the same antibody, a cDNA clone was isolated from epidermal mRNA. The hybrid selected mRNA coded for only one protein with an apparent MW of 22 kDa which was, furthermore, recognized by the antibody. The Northern blot analysis performed with the clone confirmed the Western blot analysis of the in vitro translation products. JHA application at the beginning of the pupal-adult reprogramming prevented the appearance of this mRNA; however, this transcript was present during the following molting cycle. This reversibility of the JHA action was confirmed by immunogold labeling of the cuticles formed in treated animals. 68 NAL Call. No.: 448.3 J82 A diffusible compound can enhance conjugal transfer of the Ti plasmid in Agrobacterium tumefaciens. Zhang, L.; Kerr, A. Washington, D.C. : American Society for Microbiology; 1991 Mar. Journal of bacteriology v. 173 (6): p. 1867-1872. ill; 1991 Mar. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Strains; Nopaline; Octopine; Plasmids; Transfer; Genetic regulation; Temperature Abstract: Several octopine strains of Agrobacterium tumefaciens were tested for Ti plasmid (pTi) transfer after induction by 400 microgram of octopine per ml for 24 h. The strains could be divided into two groups, transfer efficient (Tra(e)) and transfer inefficient (Tra(ie)); the respective rates of transfer were 0.77 X 10(-2) to 1.14 X 10(-2) and 0.33 X 10(-6) to 9.8 X 10(-6) plasmid transconjugant per donor cell. Transfer efficiencies of Tra(ie) strains were greatly increased when the time of induction was 72 h. A diffusible conjugation factor (CF) that can enhance conjugal transfer of pTi in A. tumefaciens was discovered when both Tra(e) and Tra(ie) donor strains were induced in the same plate. The evidence indicates that CF is a key factor affecting transfer efficiency of pTi but is not sufficient by itself to induce transfer. Tra(c) mutants can produce CF constitutively, and Tra(e) strains can produce it after induction by low octopine concentrations. The transfer efficiency of Tra(ie) strains was greatly increased by adding CF to the induction medium. The thermosensitive strain B6S3, which normally cannot conjugate at temperatures above 30 degrees C, could transfer pTi efficiently at 32 and 34 degrees C in the presence of CF. Production of CF is dependent on the presence of pTi but appears to be common for different opine strains; it was first detected in octopine strains, but nopaline strains also produced the same or a similar compound. CF is very biologically active, affecting donor but not recipient bacterial cells, but CF does not promote aggregation. Data suggest that CF might be an activator or derepressor in the conjugation system of A. tumefaciens. CF is a dialyzable small molecule and is resistant to DNase, RNase, protease, and heating to 100 degrees C for 10 min, but autoclaving (121 degrees C for 15 min) and alkaline treatment removed all activity. 69 NAL Call. No.: aSB205.S7S6 Disease response of soybean cultivars to Phytophthora megasperma f.sp. glycinea race 16 following gene transfer at the Rps1 locus. Wagner, R.E.; Bernard, R.L. Ames, Iowa : The Service; 1991. Soybean genetics newsletter - U.S. Department of Agriculture, Agricultural Research Service v. 18: p. 240-242; 1991. Includes references. Language: English Descriptors: Glycine; Cultivars; Disease resistance; Phytophthora megasperma 70 NAL Call. No.: 448.39 SO12 The dispersal of bacteria from leaf surfaces by water splash. Butterworth, J.; McCartney, H.A. Oxford : Blackwell Scientific Publications; 1991 Dec. The Journal of applied bacteriology v. 71 (6): p. 484-496; 1991 Dec. Includes references. Language: English Descriptors: Phaseolus vulgaris; Brassica napus; Leaves; Pseudomonas syringae; Klebsiella; Bacillus subtilis; Genetic engineering; Plant disease control; Rain; Surfaces; Water spreading; Bacterial count; Dispersal; Droplet studies; Quantitative analysis Abstract: Advances in the techniques of genetic engineering have made possible the use of genetically manipulated micro- organisms (GMOs) for the control of pests and diseases. Before GMOs can be widely used in agriculture, however, their fate after release must be understood. Dispersal of released GMOs will have an important influence on their action or survival under field conditions. The object of this study was to quantify the efficiency of rain an a means of removing and disseminating such micro-organisms from foliar crop surfaces. Spontaneous mutants of three species of bacteria (Pseudomonas syringae, Klebseilla planticola and Bacillus subtilis), resistant to the antibiotic rifampicin, were sprayed on two plant species, french bean, Phaseolus vulgaris, and oilseed rape, Brassica napus. The leaves from the plants were then exposed to artificial rain and splash droplets generated by the impact on the leaves were collected on selective nutrient agar in Petri dishes and in sterile glass 28 ml screw-capped bottles. The bacterial content of the splash drops was assessed, as was the content of water which ran off the leaf surfaces. Comparisons of the numbers of bacteria removed from the leaves with the numbers applied prior to splashing show that rainfall can be a very efficient means of removing bacteria from foliar surfaces, but that most of the removed bacteria run off to the soil. Only a small proportion was splashed relatively short distances from the source. 71 NAL Call. No.: 442.8 Z34 Disruption of a Magnaporthe grisea cutinase gene. Sweigard, J.A.; Chumley, F.G.; Valent, B. Berlin, W. Ger. : Springer International; 1992 Mar. M G G : Molecular and general genetics v. 232 (2): p. 183-190; 1992 Mar. Includes references. Language: English Descriptors: Magnaporthe grisea; Genes; Esterases; Induced mutations; Mutants; Genetic transformation; Cutin; Hydrolysis; Pathogenicity; Fungal diseases; Oryza sativa; Hordeum vulgare; Eragrostis curvula Abstract: Using a one-step strategy to disrupt CUT1, a gene for cutinase, cut1- mutants were generated in two strains of Magnaporthe grisea. One strain, pathogenic on weeping lovegrass and barley and containing the arg3-12 mutation, was transformed with a disruption vector in which the Aspergillus nidulans ArgB+ gene was inserted into CUT1. Prototrophic transformants were screened by Southern hybridization, and 3 of 53 tested contained a disrupted CUT1 gene (cut1::ArgB+). A second strain, pathogenic on rice, was transformed with a disruption vector in which a gene for hyg B resistance was inserted into CUT1. Two of the 57 transformants screened by Southern hybridization contained a disrupted CUT1 gene (cut1:: Hyg). CUT1 mRNA was not detectable in transformants that contained a disrupted gene. Transformants with a disrupted CUT1 gene failed to produce a cutin-inducible esterase that is normally detected by activity staining on non-denaturing polyacrylamide gels. Enzyme activity, measured either with tritiated cutin or with p-nitrophenyl butyrate as a substrate, was reduced but not eliminated in strains with a disrupted CUT1 gene. The infection efficiency of the cut1- disruption transformants was equal to that of the parent strains on all three host plants. Lesions produced by these mutants had an appearance and a sporulation rate similar to those produced by the parent strains. We conclude that the M. grisea CUT1 gene is not required for pathogenicity. 72 NAL Call. No.: 464.8 P56 Distribution and multiplication of western aster yellows mycoplasmalike organisms in Catharanthus roseus as determined by DNA hybridization analysis. Kuske, C.R.; Kirkpatrick, B.C. St. Paul, Minn. : American Phytopathological Society; 1992 Apr. Phytopathology v. 82 (4): p. 457-462; 1992 Apr. Includes references. Language: English Descriptors: Catharanthus roseus; Aster yellows; Mycoplasma- like organisms; Disease distribution; Strains; Colonizing ability; Detection; Dna probes; Symptomatology; Host parasite relationships Abstract: Mycoplasmalike organism (MLO) specific DNA probes derived from chromosomal or plasmid DNA of the severe strain of western aster yellows MLO (SAY) were used to monitor the distribution and multiplication of MLOs in periwinkle plants infected with the SAY or dwarf strain (DAY) of the western AY MLO. Plants were graft-inoculated, and DNA was extracted from different regions of the inoculated plants over a 10-wk period. DNA samples were applied to nitrocellulose membranes and hybridized to cloned, 32P-labeled, MLO-specific DNA probes. Relative concentration and distribution of MLOs were determined by measuring the amount of hybridized probe. Colonization patterns for the two AY-MLO strains were similar. The MLOs were first detected in grafted shoots about 2 wk before symptoms appeared. From the grafted shoots, the MLOs moved into ungrafted shoots, and then systemically throughout the plant. Distribution and concentration of MLOS correlated directly with expression of virescence and proliferation symptoms in aerial portions of the plants. MLO concentrations were highest in symptomatic, actively growing shoots and generally lowest in roots. 73 NAL Call. No.: 464.8 P56 Diversity of Xanthomonas campestris pv. citrumelo strains associated with epidemics of citrus bacterial spot in Florida citrus nurseries: correlation of detached leaf, monoclonal antibody, and restriction fragment length polymorphism assays. Gottwald, T.R.; Alvarez, A.M.; Hartung, J.S.; Benedict, A.A. St. Paul, Minn. : American Phytopathological Society; 1991 Jul. Phytopathology v. 81 (7): p. 749-753; 1991 Jul. Includes references. Language: English Descriptors: Florida; Citrus; Xanthomonas campestris; Pathotypes; Strains; Strain differences; Heterogeneity; Diversity; Virulence; Characterization; Assays; Monoclonal antibodies; Restriction fragment length polymorphism; Serological relationships Abstract: The heterogeneity of 194 previously uncharacterized strains of Xanthomonas campestris pv. citrumelo isolated from citrus bacterial spot epidemics in four citrus nurseries in central Florida was evaluated by virulence reactions on detached leaves, reaction to a panel of monoclonal antibodies (MAbs), and reaction to a panel of restriction fragment length polymorphism (RFLP) probes. Detached-leaf assays were performed on the 194 strains that had been differentiated into five serological groups based on reactions with six MAbs. A subset of 27 strains, selected because of their diverse reactions to MAbs and the detached-leaf assay, were differentiated into five reaction types by RFLP analysis. There was good agreement between serological reaction patterns and RFLP results. Both assays were capable of distinguishing strongly aggressive from less aggressive strains as indicated by detached-leaf assay. In addition, MAb and RFLP assays often detected the same unique strains within the population of strains from individual nurseries. The assays also differentiated groups of strains originating from different foci of infection in one nursery. 74 NAL Call. No.: 442.8 G28 DNA fingerprinting and analysis of population structure in the chestnut blight fungus, cryphonectria parasitica. Milgroom, M.G.; Lipari, S.E.; Powell, W.A. Baltimore, Md. : Genetics Society of America; 1992 Jun. Genetics v. 131 (2): p. 297-306; 1992 Jun. Includes references. Language: English Descriptors: Virginia; Cryphonectria parasitica; Dna fingerprinting; Dna; Restriction mapping; Loci; Inheritance; Linkage; Mutations; Dna probes; Dna hybridization; Segregation; Population genetics; Genetic polymorphism; Blight; Castanea sativa; Population structure Abstract: We analyzed DNA fingerprints in the chestnut blight fungus, Cryphonectria parasitica, for stability, inheritance, linkage and variability in a natural population. DNA fingerprints resulting from hybridization with a dispersed moderately repetitive DNA sequence of C. parasitica in plasmid pMS5.1 hybridized to 6-17 restriction fragments per individual isolate. In a laboratory cross and from progeny from a single perithecium collected from a field population, the presence/absence of 11 fragments in the laboratory cross and 12 fragments in the field progeny set segregated in 1:1 ratios. Two fragments in each progeny set cosegregated; no other linkage was detected among the segregating fragments. Mutations, identified by missing bands, were detected for only one fragment in which 4 of 43 progeny lacked a band present in both parents; no novel fragments were detected in any progeny. All other fragments appeared to be stably inherited. Hybridization patterns did not change during vegetative growth or sporulation. However, fingerprint patterns of single conidial isolates of strains EP155 and EP67 were found to be heterogenous due to mutations that occurred during culturing in the laboratory since these strains were first isolated in 1976-1977. In a population sample of 39 C. parasitica isolates, we found 33 different fingerprint patterns with pMS5.1. Most isolates differed from all other isolates by the presence or absence of several fragments. Six fingerprint patterns each occurred twice. Isolates with identical fingerprints occurred in cankers on the same chestnut stems three times; isolates within the other three pairs were isolated from cankers more than 5 m apart. The null hypothesis of random mating in this population could not be rejected if the six putative clones were removed from the analysis. Thus, a rough estimate of the clonal fraction of this population is 6 in 39 isolates (15.4%). 75 NAL Call. No.: SB732.6.M65 DNA hybridization between western aster yellows mycoplasmalike organism plasmids and extrachromosomal DNA from other plant pathogenic mycoplasmalike organisms. Kuske, C.R.; Kirkpatrick, B.C.; Davis, M.J.; Seemuller, E. St. Paul, Minn. : APS Press; 1991 Jan. Molecular plant-microbe interactions : MPMI v. 4 (1): p. 75-80; 1991 Jan. Includes references. Language: English Descriptors: Apium graveolens; Callistephus chinensis; Catharanthus roseus; Oenothera; Macrosteles; Dalbulus maidis; Mycoplasma-like organisms; Pathogenicity; Provenance; Strains; Strain differences; Dna; Plasmids; Comparisons; Genetic analysis; Dna hybridization; Characterization; Dna probes 76 NAL Call. No.: 442.8 Z34 DNA markers closely linked to nematode resistance genes in sugar beet (Beta vulgaris L.) mapped using chromosome additions and translocations originating from wild beets of the Procumbentes section. Jung, C.; Koch, R.; Fischer, F.; Brandes, A.; Wricke, G.; Herrmann, R.G. Berlin, W. Ger. : Springer International; 1992 Mar. M G G : Molecular and general genetics v. 232 (2): p. 271-278; 1992 Mar. Includes references. Language: English Descriptors: Beta vulgaris var. saccharifera; Beta; Heterodera schachtii; Repetitive DNA; Genetic markers; Polymerase chain reaction; Genetic resistance; Pest resistance; Genes; Dna fingerprinting; Linkage; Chromosome addition; Addition lines; Chromosome translocation; Translocation lines; Dna probes; Dna hybridization; Gene location; Chromosomes; Gene mapping Abstract: Genes conferring resistance to the beet cyst nematode (Heterodera schachtii Schm.) have been transferred to sugar beet (Beta vulgaris L.) from three wild species of the Procumbentes section using monosomic addition and translocation lines, because no meiotic recombination occurs between chromosomes of cultured and wild species. In the course of a project to isolate the nematode resistance genes by strategies of reverse genetics, probes were cloned from DNA of a fragmented B. procumbens chromosome carrying a resistance gene, which had been isolated by pulsed-field gel electrophoresis. One probe (pRK643) hybridized with a short dispersed repetitive DNA element, which was found only in wild beets, and thus may be used as a molecular marker for nematode resistance to progenies of monosomic addition lines segregating resistant and susceptible individuals. Additional probes for the resistance gene region were obtained with a polymerase chain reaction (PCR)-based strategy using repetitive primers to amplify DNA located between repetitive elements. One of these probes established the existence of at least six different chromosomes from wild beet species, each conferring resistance independently of the others. A strict correlation between the length of the wild beet chromatin introduced in fragment addition and translocation lines and the repeat copy number has been used physically to map the region conferring resistance to a chromosome segment of 0.5-3 Mb. 77 NAL Call. No.: 448.3 AP5 DNA probes for detection of copper resistance genes in Xanthomonas campestris pv. vesicatoria. Garde, S.; Bender, C.L. Washington, D.C. : American Society for Microbiology; 1991 Aug. Applied and environmental microbiology v. 57 (8): p. 2435-2439; 1991 Aug. Includes references. Language: English Descriptors: Xanthomonas campestris; Genes; Resistance; Copper; Strains; Plasmids Abstract: The copper resistance (Cur) genes encoded on pXV10A, a 190-kb plasmid in Xanthomonas campestris pv. vesicatoria XV10, were isolated on a 44-kb cosmid clone designated pCuR1. Tn5 mutagenesis of pCuR1 indicated that a 4.0-kb region was required for copper resistance. Three restriction fragments located within the 4.0-kb region demonstrated high specificity for the Cur genes present in X. campestris pv. vesicatoria and will be useful in monitoring the presence of these genes in the environment. 78 NAL Call. No.: QH442.G456 DNAP announces successful trial of altered plants. New York, N.Y. : Mary Ann Liebert; 1991 Jun. Genetic engineering news v. 11 (6): p. 19; 1991 Jun. Language: English Descriptors: U.S.A.; Nicotiana tabacum; Plant breeding; Genetic engineering; Chitinase; Biosynthesis; Genetic regulation; Genetic code; Plant pathogenic fungi; Genetic resistance 79 NAL Call. No.: 443.8 H42 Ecological and genetic models of host-pathogen coevolution. Frank, S.A. Oxford : Blackwell Scientific Publications; 1991 Aug. Heredity v. 67 (pt.1): p. 73-83; 1991 Aug. Includes references. Language: English Descriptors: Plants; Plant pathogens; Genetic polymorphism; Plant diseases; Evolution; Genetic models; Genetic algebras; Virulence; Genetic resistance; Disease resistance; Gene frequency Abstract: A model is presented to analyse the forces that maintain genetic polymorphism in interactions between host plants and their pathogens. Genetic variability in hosts occurs for specific resistance to different pathogen races and variability in pathogens occurs for specific virulence to different host races. The model tracks both fluctuating population sizes and changing gene frequencies. Analyses over a range of parameters show that ecological and demographic factors, such as birth and death rates, often have a more profound effect on the amount of polymorphism than genetic parameters, such as the pleiotropic costs of resistance and virulence associated with different alleles. A series of simple measures are proposed to predict the amount of genetic polymorphism expected in particular host-pathogen interactions. These measures can be used to develop and test a comparative theory of genetic polymorphism in host-pathogen coevolution. 80 NAL Call. No.: 1.9 P69P Effect of disease assessment method on ranking potato cultivars for resistance to early blight. Christ, B.J. St. Paul, Minn. : American Phytopathological Society; 1991 Apr. Plant disease v. 75 (4): p. 353-356; 1991 Apr. Includes references. Language: English Descriptors: Pennsylvania; Solanum tuberosum; Alternaria solani; Cultivars; Genetic resistance; Screening; Pathogenicity; Symptoms 81 NAL Call. No.: QR1.L47 Effect of parB on plasmid stability and gene expression in Xanthomonas campestris. Pimenta, A. de L.; Rosato, Y.B.; Astolfi-Filho, S. Oxford : Blackwell Scientific Publications; 1992 Jun. Letters in applied microbiology v. 14 (6): p. 233-237; 1992 Jun. Includes references. Language: English Descriptors: Xanthomonas campestris pv. campestris; Xanthomonas campestris pv. manihotis; Bacillus subtilis; Loci; Plasmids; Stability; Gene expression; Genetic transformation; Alpha-amylase; Reporter genes; Enzyme activity; Vectors; Cloning 82 NAL Call. No.: SB599.C8 Engineering genetic disease resistance into crops: biotechnological approaches to crop protection. Harms, C.T. Oxford : Butterworths-Heinemann Ltd; 1992 Aug. Crop protection v. 11 (4): p. 291-306; 1992 Aug. Literature review. Includes references. Language: English Descriptors: Literature reviews; Grain crops; Horticultural crops; Genetic engineering; Disease resistance; Genetic resistance; Transgenics; Plant protection; Phytoalexins; Defense mechanisms; Pathogenesis-related proteins; Genetic improvement; Somaclonal variation; In vitro selection; In vitro culture; Somatic hybridization 83 NAL Call. No.: QK710.P62 Environmental conditions differentially affect vir gene induction in different Agrobacterium strains. Role of the VirA sensor protein. Turk, S.C.H.J.; Melchers, L.S.; Dulk-Ras, H. den; Regensburg- Tunk, A.J.G.; Hooykaas, P.J.J. Dordrecht : Kluwer Academic Publishers; 1991 Jun. Plant molecular biology : an international journal on fundamental research and genetic engineering v. 16 (6): p. 1051-1059; 1991 Jun. Includes references. Language: English Descriptors: Kalanchoe tubiflora; Agrobacterium tumefaciens; Agrobacterium rhizogenes; Virulence; Genes; Gene expression; Plasmids; Genetic regulation; Bacterial proteins; Ph; Air temperature; Aromatic compounds; Strain differences Abstract: The induction of vir gene expression in different types of Agrobacterium strains shows different pH sensitivity profiles. The pH sensitivity pattern demonstrated by octopine Ti strains was similar to that of a supervirulent leucinopine Ti strain, whereas this was different from that shown by nopaline Ti strains and agropine Ri strains. Data are given which indicate that these differences are due to different properties of the virA genes of these wild types. An exceptional case was formed by strains with the limited-host- range plasmid pTiAG57 which showed AS-dependent vir induction only if reduced inoculum sizes were used and the temperature was 28 degrees C or below. 84 NAL Call. No.: 421 C16 Eudorylas (Metadorylas) sp. (Diptera: Pipunculidae): a previously unreported parasitoid of Dalbulus maidis (Delong and Wolcott) and Dalbulus elimatus (Ball) (Homoptera: Cicadellidae). Vega, F.E.; Barbosa, P.; Panduro, A.P. Ottawa : Entomological Society of Canada; 1991 Jan. The Canadian entomologist v. 123 (1): p. 241-242. ill; 1991 Jan. Includes references. Language: English Descriptors: Mexico; Zea mays; Dalbulus elimatus; Dalbulus maidis; Disease vectors; Maize rayado fino marafivirus; Mycoplasma-like organisms; Spiroplasma kunkelii; Biological control; Diptera; Parasites of insect pests 85 NAL Call. No.: 448.3 AP5 Evaluation of methods for sampling, recovery, and enumeration of bacteria applied to the phylloplane. Donegan, K.; Matyac, C.; Seidler, R.; Porteous, A. Washington, D.C. : American Society for Microbiology; 1991 Jan. Applied and environmental microbiology v. 57 (1): p. 51-56; 1991 Jan. Includes references. Language: English Descriptors: Phaseolus vulgaris; Avena sativa; Erwinia herbicola; Enterobacter cloacae; Leaves; Enumeration; Bacterial count; Sampling; Laboratory methods; Monitoring; Genetic engineering; Pot experimentation Abstract: Determining the fate and survival of genetically engineered microorganisms released into the environment requires the development and application of accurate and practical methods of detection and enumeration. Several experiments were performed to examine quantitative recovery methods that are commonly used or that have potential applications. In these experiments, Erwinia herbicola and Enterobacter cloacae were applied in greenhouses to Blue Lake bush beans (Phaseolus vulgaris) and Cayuse oats (Avena sativa). Sampling indicated that the variance in bacterial counts among leaves increased over time and that this increase caused an overestimation of the mean population size by bulk leaf samples relative to single leaf samples. An increase in the number of leaves in a bulk sample, above a minimum number, did not significantly reduce the variance between samples. Experiments evaluating recovery methods demonstrated that recovery of bacteria from leaves was significantly better with stomacher blending, than with blending, sonication, or washing and that the recovery efficiency was constant over a range of sample inoculum densities. Delayed processing of leaf samples, by storage in a freezer, did not significantly lower survival and recovery of microorganisms when storage was short term and leaves were not stored in buffer. The drop plate technique for enumeration of bacteria did not significantly differ from the spread plate method. Results of these sampling, recovery, and enumeration experiments indicate a need for increased development and standardization of methods used by researchers as there are significant differences among, and also important limitations to, some of the methods used. 86 NAL Call. No.: QL391.N4J62 Evaluation of Nicotiana otophora as a source of resistance to Meloidogyne incognita race 4 for tobacco. Reed, S.M.; Schneider, S.M. Lake Alfred, Fla. : Society of Nematologists; 1992 Jun. Journal of nematology v. 24 (2): p. 253-256; 1992 Jun. Includes references. Language: English Descriptors: Nicotiana tabacum; Nicotiana; Meloidogyne incognita; Pest resistance; Gene transfer; Genotypes; Cultivars Abstract: No currently available tobacco cultivar possesses resistance to Meloidogyne incognita race 4, nor has any source of resistance been reported within Nicotiana tabacum. The purpose of this study was to evaluate N. otophora acc. La Quinta as a source of resistance to this pathogen. Plants of tobacco cvs. NC 95 and NC 2326, N. otophora La Quinta and N. repanda were inoculated with second-stage juveniles of M. incognita race 4. Gall indices and egg-mass ratings were assessed at 4 and 8 weeks after inoculation. The two N. tabacum cultivars were heavily galled and had numerous egg masses at both rating periods. Nicotiana repanda was only weakly resistant. The galls on this species were very small and present at a low to moderate level; however, egg-mass ratings approaching those of the tobacco cultivars were observed 8 weeks after inoculation. In contrast, low gall indices and egg-mass ratings were found for N. otophora La Quinta at both the 4- and 8-week rating periods. In addition, little variability was observed within this species for either disease rating. Therefore, it appears that the La Quinta accession of N. otophora is a very promising source of M. incognita race 4 resistance for transfer to N. tabacum. 87 NAL Call. No.: QH301.N32 Evidence for Agrobacterium-mediated genetic transformation in Larix decidua. Huang, Y.; Shin, D.I.; Karnosky, D.F. New York, N.Y. : Plenum Press; 1991. NATO ASI series : Series A : Life sciences v. 210: p. 233-235; 1991. In the series analytic: Woody plant biotechnology / edited by M.R. Ahuja. Proceedings of a Workshop at the Institute of Forest Genetics, USDA Forest Service, October 15-19, 1989, Placerville, California. Includes references. Language: English Descriptors: Larix decidua; Gene expression; Genetic transformation; Agrobacterium tumefaciens 88 NAL Call. No.: SB599.P45 Evidence for the requirement of extracellular protease in the pathogenic interaction of Pyrenopeziza brassicae with oilseed rape. Ball, A.M.; Ashby, A.M.; Daniels, M.J.; Ingram, D.S.; Johnstone, K. London : Academic Press; 1991 Feb. Physiological and molecular plant pathology v. 38 (2): p. 147-161; 1991 Feb. Includes references. Language: English Descriptors: Brassica napus var. oleifera; Pyrenopeziza brassicae; Mutants; Strains; Pathogenicity; Proteinases; Enzyme activity; Proteolysis; Genetic transformation; Host parasite relationships; Molecular biology Abstract: Using a detached cotyledon test for pathogenicity, a UV-induced, non-pathogenic mutant of Pyrenopeziza brassicae was isolated which was also deficient in extracellular protease production in vitro. The proteolytic activity in the wild type was apparently due to a single cysteine protease with a mol. wt of 34 k, a temperature optimum of 40 degrees C and a pH optimum of 8. When the mutant was crossed with a wild-type isolate of P. brassicae, the non-proteolytic and non-pathogenic traits co-segregated in the resulting progeny. The protease-mutant was transformed with clones from a genomic library of P. brassicae and a transformant obtained which had a single cosmid insert and showed concomitant restoration of pathogenicity and proteolytic activity in vitro. These results suggest that extracellular protease is a pathogenicity determinant of P. brassicae and possible functions for this protease in the disease process are discussed. 89 NAL Call. No.: SB732.6.M65 Evolution of agrobacteria and their Ti plasmids: a review. Otten, L.; Canaday, J.; Gerard, J.C.; Fournier, P.; Crouzet, P.; Paulus, F. St. Paul, Minn. : APS Press; 1992 Jul. Molecular plant-microbe interactions : MPMI v. 5 (4): p. 279-287; 1992 Jul. Literature review. Includes references. Language: English Descriptors: Agrobacterium; Plasmids; Literature reviews; Phylogeny; Dna; Nucleotide sequences; Genes; Comparisons; Transposable elements; Chromosomes; Genome analysis; Plant pathogenic bacteria 90 NAL Call. No.: 381 AR2 Expression cloning in Escherichia coli and preparative isolation of the reductase coacting with chalcone synthase during the key step in the biosynthesis of soybean phytoalexins. Welle, R.; Schroder, J. Orlando, Fla. : Academic Press; 1992 Mar. Archives of biochemistry and biophysics v. 293 (2): p. 377-381; 1992 Mar. Includes references. Language: English Descriptors: Glycine max; Phytoalexins; Biosynthesis; Naringenin-chalcone synthase; Oxidoreductases; Dna; Cloning; Transformation; Gene expression; Genetic engineering; Purification; Enzyme activity Abstract: The cDNA for the reductase involved in the biosynthesis of 6'-deoxychalcone (4,2',4'-trihydroxychalcone), the first specific intermediate in the pathway to soybean phytoalexins, was cloned into the expression vector pKK233-2 and transformed into Escherichia coli. Using this source, about 5 mg of homogeneous reductase was isolated from 45 g of cells. The protein purification protocol differs completely from the scheme applied to soybean cell cultures. Size, N- terminal and specific enzyme activities were identical for the plant and E. coli protein. The pure protein is fairly stable, retaining 70% of initial activity after storage at 5 degrees C during 4 weeks. This protein is used for crystallization and in the study of its protein-protein interaction with chalcone synthase. 91 NAL Call. No.: SB732.6.M65 Expression in vitro and during plant pathogenesis of the syrB gene required for syringomycin production by Pseudomonas syringae pv. syringae. Mo, Y.Y.; Gross, D.C. St. Paul, Minn. : APS Press; 1991 Jan. Molecular plant-microbe interactions : MPMI v. 4 (1): p. 28-36; 1991 Jan. Includes references. Language: English Descriptors: Prunus avium; Pseudomonas syringae pv. syringae; Pathogenesis; Mutants; Phytotoxins; Pathogenicity; Antibiotics; Beta-galactosidase; Enzyme activity; Genes; Gene expression; In vitro; Insertional mutagenesis; Gene transfer; Strains; Strain differences 92 NAL Call. No.: QH442.B5 Expression of a barley ribosome-inactivating protein leads to increased fungal protection in transgenic tobacco plants. Logemann, J.; Jach, G.; Tommerup, H.; Mundy, J.; Schell, J. New York, N.Y. : Nature Publishing Company; 1992 Mar. Bio/technology v. 10 (3): p. 305-308; 1992 Mar. Includes references. Language: English Descriptors: Nicotiana tabacum; Hordeum vulgare; Solanum tuberosum; Rhizoctonia solani; Genetic transformation; Transgenics; Gene transfer; Structural genes; Plant proteins; Inhibitors; Translation; Ribosomes; Promoters; Genetic regulation; Abiotic injuries; Genetic resistance; Fungal diseases; Gene expression 93 NAL Call. No.: QK710.P62 Expression of a chimaeric heat-shock-inducible Agrobacterium 6b onocogene in Nicotiana rustica. Tinland, B.; Fournier, P.; Heckel, T.; Otten, L. Dordrecht : Kluwer Academic Publishers; 1992 Mar. Plant molecular biology : an international journal on molecular biology, biochemistry and genetic engineering v. 18 (5): p. 921-930; 1992 Mar. Includes references. Language: English Descriptors: Nicotiana rustica; Agrobacterium tumefaciens; Oncogenes; Tumors; Cell division; Gene expression; Abiotic injuries; Protoplasts; Callus; Chimeras; Heat shock proteins; Promoters; Reporter genes; Genetic transformation; Messenger RNA; Heat shock; Seedling stage Abstract: The T-6b gene of Agrobacterium tumefaciens strain Tm4 induces tumours on Nicotiana rustica by an as yet unknown mechanism. These tumours cannot be regenerated into normal plants. To study the effect of the T-6b gene product on normal plant cells, the T-6b gene was placed under control of the Drosophila melanogaster hsp70 heat-shock promoter and introduced into N. rustica. Progeny of an hsp70-T-6b transformant developed into normal plants. The inducibility of the hsp70-T-6b construct was shown by northern analysis and by heat-shock-dependent growth alterations on the level of whole seedlings. Upon wounding at normal temperature conditions hsp70-T-6b plants formed small tumours on leaves and stems. Grafts between transformed plants and normal plants led to a wound callus which remained limited to transformed tissues, indicating that the T-6b gene product does not diffuse. Protoplasts of hsp70-T-6b plants divided in the same way as control protoplasts under standard culture conditions. However, when protoplast cultures were started in the absence of hormones, normal cells rapidly lost their sensitivity towards hormones, whereas hsp70-T-6b cells remained sensitive for a significantly longer period. Thus, the T-6b gene product alters hormone sensitivity during the initial phases of protoplast culture. 94 NAL Call. No.: QR1.F44 Expression of a subcloned alpha-amylase gene under the control of a Xanthomonas campestris promoter. Pimenta, A.L.; Rosato, Y.B.; Astolfi-Filho, S. Amsterdam : Elsevier Science Publishers; 1991 Dec15. FEMS microbiology letters - Federation of European Microbiological Societies v. 90 (1): p. 11-18; 1991 Dec15. Includes references. Language: English Descriptors: Xanthomonas campestris pv. campestris; Xanthomonas campestris pv. manihotis; Promoters; Alpha- amylase; Genes; Gene expression; Plasmids; Clones Abstract: Using the promoter probe pKK232-8 a 0.6-kb fragment containing an active promoter sequence from Xanthomonas campestris pv campestris was cloned. Two new plasmids were constructed: (a) pAP2, which contains the amy gene from Bacillus subtilis cloned between the EcoRI and HindIII sites in the pMFY40 plasmid, and (b) pAP2X, obtained after introduction of the cloned X. campestris promoter upstream from the amy gene. These plasmids were introduced into amylolytic and non-amylolytic strains of X. campestris pv campestris and pv manihotis, respectively. Quantification of alpha-amylase specific activity in liquid culture showed that the introduction of a Xanthomonas promoter doubled the expression of amy gene when the host strain was the pathovar campestris but had little effect on the strain from pathovar manihotis. This difference in the promoter activity might indicate that the cloned promoter is specific and could be involved in pathovar differentiation or plant-pathogen interaction. 95 NAL Call. No.: 448.3 J82 Expression of Erwinia amylovora hrp genes in response to environmental stimuli. Wei, Z.M.; Sneath, B.J.; Beer, S.V. Washington, D.C. : American Society for Microbiology; 1992 Mar. Journal of bacteriology v. 174 (6): p. 1875-1882; 1992 Mar. Includes references. Language: English Descriptors: Erwinia amylovora; Genes; Gene expression; Genetic regulation; Transcription; Ph; Temperature; Ammonium; Nicotinic acid; Nitrogen; Amino acids; Mannitol; Fructose; Glycerol; Sucrose; Glucose; Maltose Abstract: Seven hrp loci that are essential for the hypersensitive reaction elicited by Erwinia amylovora were transcriptionally fused with a derivative of transposon Tn5, containing the promoterless Escherichia coli beta- glucuronidase reporter gene. The seven hrp fusions were used to monitor expression of the hrp loci in vitro and in planta. No significant expression was detected in rich medium for any of the fusions. However, five of them were expressed highly in planta and in inducing medium that contains mannitol, salts, and 5 mM (NH4)2SO4. Expression of these five hrp loci is regulated by ammonium, nicotinic acid, complex-nitrogen sources, certain carbon sources, temperature, and pH. Under well-defined conditions, i.e., in inducing medium, no specific plant components were required for transcriptional activation of the hrp loci. The high levels of expression detected in vitro were comparable to those determined during the development of the hypersensitive reaction in tobacco. Differential levels of expression of the hrp loci occurred in host and nonhost plants. In pear, a host plant, expression of the hrp loci was delayed and greatly reduced compared with expression in tobacco leaves, a nonhost. 96 NAL Call. No.: 448.3 J82 Expression of the avirulence gene avrBs3 from Xanthomonas campestris pv. vesicatoria is not under the control of hrp genes and is independent of plant factors. Knoop, V.; Staskawicz, B.; Bonas, U. Washington, D.C. : American Society for Microbiology; 1991 Nov. Journal of bacteriology v. 173 (22): p. 7142-7150; 1991 Nov. Includes references. Language: English Descriptors: Xanthomonas campestris pv. vesicatoria; Genes; Gene expression; Plasmids; Capsicum annuum; Genetic regulation Abstract: The avirulence gene avrBs3 from Xanthomonas campestris pv. vesicatoria pepper race 1 is responsible for the induction of a race-specific hypersensitive reaction in resistant pepper cultivars. A DNA region of 3.7 kb, containing several open reading frames and an internal repetitive region, was shown previously to be necessary for avirulence activity (U. Bonas, R. E. Stall, and B. Staskawicz, Mol. Gen. Genet. 218:127-136, 1989). The promoter of avrBs3 was identified by using gene fusions to beta-glucuronidase. Also, we mapped the transcription start site and showed that the avrBs3 gene is expressed constitutively in cells grown in minimal or complex medium and in planta. Polyclonal antibodies raised against a fusion protein produced in Escherichia coli allowed the identification of a 122-kDa protein in X. campestris pv. vesicatoria cells expressing the avrBs3 gene. The antibody is specific for AvrBs3 in X. campestris pv. vesicatoria cells but also recognizes homologous proteins in other pathovars of X. campestris. We found that AvrBs3 is localized intracellularly in X. campestris pv. vesicatoria and is mainly in the soluble fraction. The effect of mutations in the hrp gene cluster on the function of AvrBs3 was examined. Expression of AvrBs3 in X. campestris pv. vesicatoria grown in minimal or complex medium is independent of the hrp gene cluster that determines pathogenicity and hypersensitivity to X. campestris pv. vesicatoria. In the plant, however, the hrp genes are required for elicitation of a race-specific resistance response. 97 NAL Call. No.: 448.3 AP5 Expression of the Escherichia coli beta-glucuronidase gene in Pseudocercosporella herpotrichoides. Bunkers, G.J. Washington, D.C. : American Society for Microbiology; 1991 Oct. Applied and environmental microbiology v. 57 (10): p. 2896-2900; 1991 Oct. Includes references. Language: English Descriptors: Pseudocercosporella herpotrichoides; Genetic analysis; Genetic transformation; Escherichia coli; Beta- glucuronidase; Enzyme activity; Gene expression; Genetic markers; Plant pathogens; Hordeum vulgare; Triticum aestivum; Secale cereale Abstract: The plant-pathogenic fungus Pseudocercosporella herpotrichoides has been successfully transformed by using two different positive selection systems in combination with the Escherichia coli gusA gene. The selectable markers used in this study were the hygromycin B phosphotransferase gene (hph) from E. coli and the gene (bml) for beta-tubulin from a benomyl-resistant mutant of Neurospora crassa. A lower transformation rate was obtained with the bml system than with the hph system. Conversely, cotransformation frequencies, as determined with medium plates containing the chromogenic substrate 5-bromo-4-chloro-3-indolyl-beta-D-glucuronic acid, were higher with bml than with hph as the selectable marker. The hygromycin-resistant transformants were mitotically stable, and both the selectable gene and gusA were maintained through conidiation. The vector DNA was integrated into the genome, and the number and sites of insertion varied among transformants. Enzyme assays of mycelial extracts showed that beta-glucuronidase activity was highest in transformants with a high gusA copy number. Expression of gusA during growth of the fungus on plants was easily detectable and did not affect pathogenicity. These results form the basis for construction of a versatile and sensitive reporter gene system for P. herpotrichoides. 98 NAL Call. No.: 448.3 J82 Extracellular secretion of pectate lyase by the Erwinia chrysanthemi out pathway is dependent upon Sec-mediated export across the inner membrane. He, S.Y.; Schoedel, C.; Chatterjee, A.K.; Collmer, A. Washington, D.C. : American Society for Microbiology; 1991 Jul. Journal of bacteriology v. 173 (14): p. 4310-4317; 1991 Jul. Includes references. Language: English Descriptors: Erwinia chrysanthemi; Pectate lyase; Secretion; Plasma membranes; Cell membranes; Genes; Bacterial proteins; Genetic engineering; Cell structure; Alkaline phosphatase Abstract: The plant pathogenic enterobacterium Erwinia chrysanthemi EC16 secretes several extracellular, plant cell wall-degrading enzymes, including pectate lyase isozyme PelE. Secretion kinetics of 35S-labeled PelE indicated that the precursor of PelE was rapidly processed by the removal of the amino-terminal signal peptide and that the resulting mature PelE remained cell bound for less than 60 s before being secreted to the bacterial medium. PelE-PhoA (alkaline phosphatase) hybrid proteins generated in vivo by TnphoA insertions were mostly localized in the periplasm of E. chrysanthemi, and one hybrid protein was observed to be associated with the outer membrane of E. chrysanthemi in an out gene-dependent manner. A gene fusion resulting in the substitution of the beta-lactamase signal peptide for the first six amino acids of the PelE signal peptide did not prevent processing or secretion of PelE in E. chrysanthemi. When pelE was overexpressed, mature PelE protein accumulated in the periplasm rather than the cytoplasm in cells of E. chrysanthemi and Escherichia coli MC4100 (pCPP2006), which harbors a functional cluster of E. chrysanthemi out genes. Removal of the signal peptide from pre-PelE was SecA dependent in E. coli MM52 even in the presence of the out gene cluster. These data indicate that the extracellular secretion of pectic enzymes by E. chrysanthemi is an extension of the Sec- dependent pathway for general export of proteins across the bacterial inner membrane. 99 NAL Call. No.: SB599.C35 Extrachromosomal DNA elements of plant pathogenic mycoplasmalike organisms. Denes, A.S.; Sinha, R.C. Guelph, Ont. : Canadian Phytopathological Society; 1991. Canadian journal of plant pathology; Revue Canadienne de phytopathologie v. 13 (1): p. 26-32; 1991. Includes references. Language: English Descriptors: Callistephus chinensis; Mycoplasma-like organisms; Genetic analysis; Dna; Molecular weight; Plasmids; Strains; Strain differences; Nucleotide sequences; Characterization; Patterns; Dna hybridization 100 NAL Call. No.: 442.8 G28 Extrachromosomal recombination is deranged in the rec2 mutant of Ustilago maydis. Fotheringham, S.; Holloman, W.K. Baltimore, Md. : Genetics Society of America; 1991 Dec. Genetics v. 129 (4): p. 1053-1060; 1991 Dec. Includes references. Language: English Descriptors: Ustilago zeae; Plasmids; Recombination; Mutants; Genetic transformation Abstract: Transformation of a leu1 auxotroph of Ustilago maydis to prototrophy with an autonomously replicating plasmid containing the selectable LEU1 gene was found to be efficient regardless of whether the transforming DNA was circular or linear. When pairs of autonomously replicating plasmids bearing noncomplementing leu1 alleles were used to cotransform strains deleted entirely for the genomic copy of the LEU1 gene, Leu+ transformants were observed to arise by extrachromosomal recombination. The frequency of recombination increased severalfold when one plasmid of the pair was made linear by cleavage at one end of the leu1 gene, but increased 10-100-fold when both plasmids were first made linear. The increase in recombination noted in wild-type and rec1 strains was not apparent in the rec2 mutant unless the members of the pair of plasmids were cut at opposite ends of the leu1 gene to yield linear molecules offset in only one of the two possible configurations. Use of a pair of plasmid substrates designed to measure nonreciprocal and multiple exchange events revealed only a minor fraction of the total events arise through these modes, and further that no stimulation occurred when the plasmid DNA was linear. It is unlikely that the defect in rec2 lies in a mismatch correction step since a high yield of Leu+ recombinants was obtained from the rec2 mutant when it was transformed with heteroduplex DNA constructed from plasmids with the two different leu1 alleles. 101 NAL Call. No.: QK725.P54 Factors influencing the efficiency of T-DNA transfer during co-cultivation of Antirrhinum majus with Agrobacterium tumefaciens. Holford, P.; Hernandez, N.; Newbury, H.J. Berlin, W. Ger. : Springer International; 1992 May. Plant cell reports v. 11 (4): p. 196-199; 1992 May. Includes references. Language: English Descriptors: Antirrhinum majus; Cultivars; Cell culture; Culture media; Gene transfer; Genetic transformation; Tumors; Tissue culture; Agrobacterium tumefaciens; Strains; Virulence Abstract: The effects of varying the pH of the co-cultivation medium, additions of vir-inducing phenolic compounds and the strains of wild-type agrobacteria on transformation rates of a number of different varieties of Antirrhinum majus were studied. In general, optimal transformation was found with strains C58 or A281 and was favoured by low pH and the inclusion of acetosyringone in the co-cultivation medium. However, maximal transformation of the least susceptible variety was achieved at high pH and in the presence of syringaldehyde. This demonstrates the need for the optimization of a wide range of culture conditions when working with new genotypes and offers a rational approach towards the development of Agrobacterium-mediated transformation of new species or varieties. 102 NAL Call. No.: QH506.E46 Fasciation induction by the phytopathogen Rhodococcus fascians depends upon a linear plasmid encoding a cytokinin synthase gene. Crespi, M.; Messens, E.; Caplan, A.B.; Montagu, M. van; Desomer, J. Oxford, Eng. : IRL Press; 1992 Mar. The EMBO journal - European Molecular Biology Organization v. 11 (3): p. 795-804; 1992 Mar. Includes references. Language: English Descriptors: Nicotiana tabacum; Rhodococcus fascians; Plasmids; Transferases; Genes; Loci; Galls; Leaves; Virulence; Fasciation; Restriction mapping; Mutants; Gene expression; Nucleotide sequences; Amino acid sequences Abstract: Rhodococcus fascians is a nocardiform bacteria that induces leafy galls (fasciation) on dicotyledonous and several monocotyledonous plants. The wild-type strain D188 contained a conjugative, 200 kb linear extrachromosomal element, pFiD188. Linear plasmid-cured strains were avirulent and reintroduction of this linear element restored virulence. Pulsed field electrophoresis indicated that the chromosome might also be a linear molecule of 4 megabases. Three loci involved in phytopathogenicity have been identified by insertion mutagenesis of this Fi plasmid. Inactivation of the fas locus resulted in avirulent strains, whereas insertions in the two other loci affected the degree of virulence, yielding attenuated (aft) and hypervirulent (hyp) bacteria. One of the genes within the fas locus encoded an isopentenyltranferase (IPT) with low homology to analogous proteins from Gram- negative phytopathogenic bacteria. IPT activity was detected after expression of this protein in Escherichia coli cells. In R. fascians, ipt expression could only be detected in bacteria induced with extracts from fasciated tissue. R. fascians strains without the linear plasmid but containing this fas locus alone could not provoke any phenotype on plants, indicating additional genes from the linear plasmid were also essential for virulence. These studies, the first genetic analysis of the interaction of a Gram-positive bacterium with plants, suggest that a novel mechanism for plant tumour induction has evolved in R. fascians independently from the other branches of the eubacteria. 103 NAL Call. No.: 448.3 AP5 Fate of DNA encoding hygromycin resistance after meiosis in transformed strains of Gibberella fujikuroi (Fusarium moniliforme). Leslie, J.F.; Dickman, M.B. Washington, D.C. : American Society for Microbiology; 1991 May. Applied and environmental microbiology v. 57 (5): p. 1423-1429; 1991 May. Includes references. Language: English Descriptors: Gibberella fujikuroi; Meiosis; Genetic transformation; Hygromycin b; Drug resistance; Stability; Inheritance Abstract: Stability of foreign DNA transformed into a novel host is an important parameter in decisions to permit the release of genetically engineered microorganisms into the environment. Meiotic instability of transformed DNA has been reported in fungi such as Ascobolus, Aspergillus, and Neurospora. We used strains of Gibberella fujikuroi (Fusarium moniliforme) transformed with the hygr gene from Escherichia coli to study meiotic stability of foreign DNA in this plant pathogenic fungus. Crosses with single-copy transformants segregated hygr:hygs in a 1:1 manner consistent with that expected for a Mendelian locus in a haploid organism. Multicopy transformants, however, segregated hygr:hygs in a 1:2 manner that was not consistent with Mendelian expectations for a chromosomal marker, even though two unrelated auxotrophic nuclear genes were segregating normally. Segregation ratios in crosses in which hygr was introduced via the male parent did not differ significantly from crosses in which the transformed strain served as the female parent. Some of the sensitive progeny from the crosses with the multicopy transformants carried hygr sequences. When these phenotypically sensitive progeny were crossed with a wild-type strain that carried no hygr sequences, some of the progeny were phenotypically hygr. Some progeny from some crosses were more resistant to hygromycin than were their sibs or the transformant strains that served as their parents. Transformants passaged through a maize plant only rarely segregated progeny with the high levels of resistance. The mechanism underlying these genetic instabilities is not clear but may involve unequal crossing over or methylation or both. Further work with cloned genes with homology to sequences already present in the Fusarium genome is warranted. 104 NAL Call. No.: QL461.E532 Field detection of X-disease mycoplasmalike organism in Paraphlepsius irroratus (Say) (Homoptera: Cicadellidae) using a DNA probe. Rahardja, U.; Whalon, M.E.; Garcia-Salazar, C.; Yan, Y.T. Lanham, Md. : Entomological Society of America; 1992 Feb. Environmental entomology v. 21 (1): p. 81-88. ill; 1992 Feb. Includes references. Language: English Descriptors: Michigan; Prunus avium; Prunus persica; Cicadellidae; Disease vectors; Mycoplasma-like organisms; Seasonal variation; Geographical distribution Abstract: The seasonal and geographic distribution of X- diseased Paraphlepsius irroratus (Say) was studied in south, central, and northwest Michigan in 1988 and 1989 using a DNA probe. C6c, a fragment of pWX1 derived from infected Colladonus montanus (Van Duzee), detected eastern X-disease in diseased P. irroratus. Maximum numbers of infected leafhoppers were detected at the beginning of the emergence of each generation in early June and in late September. In early summer the percentage of X-diseased leafhoppers at the various sites ranged from 12.2 to 43.3%, and in the late season from 3.3 to 36.4%. The X-diseased leafhoppers occurred only in south and central Michigan. 105 NAL Call. No.: TP248.2.B562 Field testing of genetically engineered microorganisms. Drahos, D.J. Oxford : Pergamon Press; 1991. Biotechnology advances v. 9 (2): p. 157-171; 1991. Includes references. Language: English Descriptors: Uk; Australia; California; South Carolina; Washington; Montana; Indiana; Maryland; Nebraska; Illinois; Minnesota; Wisconsin; Mississippi; Plant pathogenic bacteria; Soil bacteria; Field tests; Genetic engineering; Genetic transformation; Recombination; Genes; Modification; Marker genes; Gene expression; Persistence; Risk; Assessment; Biological control; Endotoxins; Nitrogen fixation; Baculovirus; Migration; Reviews 106 NAL Call. No.: 448.3 J82 First step toward a virus-derived vector for gene cloning and expression in spiroplasmas, organisms which read UGA as a tryptophan codon: synthesis of chloramphenicol acetyltransferase in Spiroplasma citri. Stamburski, C.; Renaudin, J.; Bove, J.M. Washington, D.C. : American Society for Microbiology; 1991 Apr. Journal of bacteriology v. 173 (7): p. 2225-2230; 1991 Apr. Includes references. Language: English Descriptors: Spiroplasma citri; Bacteriophages; Escherichia coli; Vectors; Cloning; Chloramphenicol acetyltransferase; Reporter genes; Transfection; Transcription; Initiation; Gene expression; Messenger RNA; Nucleotide sequences; Genetic code; Genetic transformation; Dna; Tryptophan Abstract: Spiroplasmas are wall-less procaryotes in which the UGA codon serves not as a stop signal but as a code for the amino acid tryptophan. Spiroplasma genes that contain UGA codons thus cannot be studied in the usual Escherichia coli cloning and expression systems. Although this problem can be circumvented by using UGA-suppressor strains of E. coli, spiroplasmas themselves would provide a more efficient cloning and expression host. We have now successfully employed the replicative form (RF) of a filamentous spiroplasma virus (SpV1) to clone and express the E. coli-derived chloramphenicol acetyltransferase (CAT) gene in Spiroplasma citri. The CAT gene was inserted in one of the four intergenic regions of the SpV1 RF and introduced into cells by electroporation. Both the RF and the virion DNA produced by the transfected cells contained the CAT gene sequences. Northern blot analysis, primer extension, and S1 mapping showed that transcription of the CAT gene started from a promoter located on the SpV1 RF and was terminated downstream of the CAT gene, still within the viral RF. Expression of the CAT gene was demonstrated by acetylation of chloramphenicol by cell-free extracts from the transfected spiroplasmas. 107 NAL Call. No.: 448.3 J82 Formation of bacterial membrane ice-nucleating lipoglycoprotein complexes. Kozloff, L.M.; Turner, M.A.; Arellano, F. Washington, D.C. : American Society for Microbiology; 1991 Oct. Journal of bacteriology v. 173 (20): p. 6528-6536; 1991 Oct. Includes references. Language: English Descriptors: Pseudomonas syringae; Erwinia herbicola; Ice; Nucleation; Temperature; Proteins; Phosphatidylinositols; Mannose; Glucosamine; Galactose; Glycoproteins Abstract: The preliminary finding that nonprotein additions to the protein product of the ice-nucleating gene of Pseudomonas syringae or Erwinia herbicola are essential for ice nucleation at the warmest temperatures has led to experiments aimed at identifying possible linkages between the ice protein and the other components. It appears that the protein is coupled to various sugars through N- and O-glycan linkages. Mannose residues are apparently bound via an N- glycan bond to the amide nitrogen of one or more of the three essential asparagine residues in the unique amino-terminal portion of the protein. In turn, these mannose residues are involved in the subsequent attachment of phosphatidylinositol to the nucleation structure. This phosphatidylinositol- mannose-protein structure is the critical element in the class A nucleating structure. in addition to sugars attached to the asparagine residues, additional sugar residues appear to be attached by O-glycan linkages to serine and threonine residues in the primary repeating octapeptide, which makes up 70% of the total ice protein. These additional sugar residues include galactose and glucosamine and most likely additional mannose residues. These conclusions were based on (i) the changes in ice-nucleating activity due to the action of N- and O- glycanases, alpha- and beta-mannosidoses, and beta- galactosidase; (ii) immunoblot analyses of ice proteins in cell extracts after enzyme treatments; and (iii) the properties of transformed Ice+ Escherichia coli cells containing plasmids with defined amino-terminal and carboxyl- terminal deletions in the ice gene. Finally, evidence is presented that these sugar residues may play a role in aggregating the ice gene lipoglycoprotein compound into larger aggregates, which are the most effective ice nucleation structures. 108 NAL Call. No.: 442.8 Z34 Fot1, a new family of fungal transposable elements. Daboussi, M.J.; Langin, T.; Brygoo, Y. Berlin, W. Ger. : Springer International; 1992 Mar. M G G : Molecular and general genetics v. 232 (1): p. 12-16; 1992 Mar. Includes references. Language: English Descriptors: Fusarium oxysporum; Transposable elements; Nucleotide sequences; Repetitive DNA; Genetic change; Mutations; Nitrate reductase; Structural genes; Insertional mutagenesis; Amino acid sequences; Restriction mapping Abstract: We report here the discovery of a family of transposable elements, which we refer to as Fot1 elements, in the fungal plant pathogen Fusarium oxysporum. The first element was identified as an insertion in the gene encoding nitrate reductase. It is 1928 bp long, has 44 bp inverted terminal repeats, contains a large open reading frame and is flanked by a 2 bp (TA) target site duplication. This element shares significant structural similarities with a class of transposons that includes Tc1 from Caenorhabditis elegans and therefore represents a new class of transposable elements in fungi. 109 NAL Call. No.: SB732.6.M65 Further characterization of an hrp gene cluster of Erwinia amylovora. Bauer, D.W.; Beer, S.V. St. Paul, Minn. : APS Press; 1991 Sep. Molecular plant-microbe interactions : MPMI v. 4 (5): p. 493-499; 1991 Sep. Includes references. Language: English Descriptors: Nicotiana tabacum; Pyrus communis; Erwinia amylovora; Strains; Mutants; Host parasite relationships; Pathogenicity; Strain differences; Genes; Pathogenesis; Stress response; Plasmids; Cosmids 110 NAL Call. No.: QK600.M82 Gall development in hairy root cultures infected with Plasmodiophora brassicae. Graveland, R.; Dale, P.; Mithen, R. Cambridge : Cambridge University Press; 1992 Mar. Mycological research v. 96 (pt.3): p. 225-228; 1992 Mar. Includes references. Language: English Descriptors: Brassica napus; Agrobacterium rhizogenes; Transgenics; Plant pathogenic fungi; Galls; Developmental stages; Plant anatomy 111 NAL Call. No.: 464.8 P692 Gametic disequilibria between virulence genes in barley powdery mildew populations in relation to selection and recombination. I. Models. Ostergard, H.; Hovmoller, M.S. Oxford : Blackwell Scientific Publications; 1991 Jun. Plant pathology v. 40 (2): p. 166-177; 1991 Jun. Includes references. Language: English Descriptors: Hordeum vulgare; Erysiphe graminis; Mildews; Genetic models; Genetic algebras; Virulence; Genes; Linkage disequilibrium; Genetic resistance; Disease resistance; Recombination; Natural selection; Genotypes; Gene frequency; Cultivars; Population genetics Abstract: Two- and three-locus models were developed to study the dynamics of gametic disequilibria (linkage disequilibria) between virulence genes in an aerial population of a haploid, biotrophic pathogen. illustrated by the fungus Erysiphe graminis f.sp. hordei. The models predicted that selection induced by two or three resistance genes in host varieties would generate gametic disequilibria between the corresponding virulence genes and that recombination taking place during sexual reproduction in most cases would reduce the amount of gametic disequilibrium attained by selection. The reduction of gametic disequilibrium during sexual reproduction depended on the recombination frequency multiplied by the proportion of spores produced by sexual reproduction and by the relative acreage of varieties on which the virulence genes considered were 'unnecessary'. The dynamics of gametic disequilibria in the aerial population were shown to be different depending on the use of resistance genes in host varieties. Two resistance genes present mainly in different varieties would generate negative gametic disequilibrium between the corresponding virulence genes, whereas two resistance genes present mainly in the same variety would generate positive gametic disequilibrium between the corresponding virulence genes. In both cases, the signs would be maintained as predicted until the virulence genes became fixed. However, if the disequilibrium initially was non-zero with a sign opposite to that predicted from the distribution of the varieties, then the sign of the disequilibrium would not change instantaneously. These general results were valid for sexual as well as asexual reproduction. The predictions of the models were largely in accordance with those observed in Danish barley powdery mildew populations (Hovmoller & Ostergard, 1991). The results of the models were complemented by numerical studies to illustrate the dynamics of gametic disequilibria in specific cases, and to demonstrate th 112 NAL Call. No.: 464.8 P692 Gametic disequilibria between virulence genes in barley powdery mildew populations in relation to selection and recombination. II. Danish observations. Hovmoller, M.S.; Ostergard, H. Oxford : Blackwell Scientific Publications; 1991 Jun. Plant pathology v. 40 (2): p. 178-189; 1991 Jun. Includes references. Language: English Descriptors: Jutland; Fyn; Denmark; Hordeum vulgare; Erysiphe graminis; Mildews; Linkage disequilibrium; Virulence; Genes; Natural selection; Recombination; Genotypes; Population genetics; Disease resistance; Genetic resistance; Cultivars; Genetic variation; Line differences; Geographical distribution Abstract: Analyses of gametic disequilibria (linkage disequilibria) between virulence genes were carried out on 14 samples of Erysiphe graminis f.sp. hordei collected from the aerial population at six Danish localities from 1985 to 1988. in most samples, the virulence genotypes Va7Va12, Va9Va12, Va12Vk, Va7V(La), VkV(La) and VhV(La) were significantly less frequent than the product of the corresponding gene frequencies (negative gametic disequilibrium), while the virulence genotypes Va7Vk, Va9Vk, Va6Vh, Va7Vh and VkVh, were significantly more frequent than the product of the corresponding gene frequencies (positive gametic disequilibrium). These results could largely be explained by the distribution of powdery mildew resistance genes in the barley varieties grown in Denmark. Selection forces induced by two resistance genes present mainly in different varieties were likely to generate negative gametic disequilibrium between the corresponding virulence genes, whereas selection forces induced by two resistance genes present mainly in the same variety were likely to generate positive gametic disequilibrium between the corresponding virulence genes. This pattern was in accordance with that predicted from two- and three-locus models comprising recombination and selection induced by host resistance genes (Ostergard & Hovmoller, 1991). It was concluded that such a model system is necessary for designing an ideal strategy for the deployment of varieties (resistance genes), and that the signs of gametic disequilibria do not provide adequate information for that purpose. 113 NAL Call. No.: QH431.G452 Gamma irradiation induced in an alien chromosome segment of the wheat 'Indis' and their use in gene mapping. Marais, G.F. Ottawa : National Research Council of Canada; 1992 Apr. Genome v. 35 (2): p. 225-229; 1992 Apr. Includes references. Language: English Descriptors: Triticum aestivum; Thinopyrum; Deletions; Chromosome translocation; Translocation lines; Irradiation; Gamma radiation; Mutants; Induced mutations; Gene mapping; Gene transfer; Genetic markers; Cultivars; Genetic resistance; Rust diseases Abstract: Deletion mutants were produced in a translocated chromosome segment derived from Thinopyrum distichum (Thunb.) Love. Spikes of the translocation line 'Indis' were irradiated with gamma rays at dosages of 15, 20, and 25 Gy. The irradiated spikes were pollinated with 'Inia 66' pollen and the F2 and F3 generations screened for translocation mutants, using the genes for leaf rust resistance and yellow endosperm pigmentation as markers. Finally, endopeptidase polymorphisms were utilized to select mutant translocation homozygotes within each of 29 families. An investigation of polymorphisms at the alpha-Amy-D2 and Wsp-D1 loci of chromosome arm 7DL revealed that 'Indis' did not produce an alpha-AMY-D2 product, but it did produce a novel WSP-D1 protein. The mutants were characterized for their leaf and stem rust resistances and the presence of WSP-D1 and yellow flour pigments. The stem rust resistance gene could not be accurately mapped. The linear order of the remaining loci on 7DL was centromere--leaf rust resistance--Wsp-D1 and yellow pigment. The data obtained suggested that the 'Indis' translocation has homo(eo)logy to the Lr19 translocation and homoeology to 7DL of common wheat. 114 NAL Call. No.: 448.3 J82 A gene cluster required for coordinated biosynthesis of lipopolysaccharide and extracellular polysaccharide also affects virulence of Pseudomonas solanacearum. Kao, C.C.; Sequeira, L. Washington, D.C. : American Society for Microbiology; 1991 Dec. Journal of bacteriology v. 173 (24): p. 7841-7847; 1991 Dec. Includes references. Language: English Descriptors: Pseudomonas solanacearum; Genes; Biosynthesis; Polysaccharides; Lipopolysaccharides; Pathogenesis; Virulence Abstract: Bacterial cell surface components can be important determinants of virulence. At least three gene clusters important for extracellular polysaccharide (EPS) biosynthesis have been previously identified in the plant pathogen Pseudomonas solanacearum. We have found that one of these gene clusters, named ops, is also required for lipopolysaccharide (LPS) biosynthesis. Mutations in any complementation unit of this cluster decreased EPS production, prevented the binding of an LPS-specific phage, and altered the mobility of purified LPS in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. However, restoration of LPS biosynthesis alone was not sufficient to restore virulence to the wild-type level, suggesting that EPS is important for pathogenesis. 115 NAL Call. No.: SB732.6.M65 Gene-for-gene interactions between Pseudomonas syringae pv. phaseolicola and Phaseolus. Jenner, C.; Hitchin, E.; Mansfield, J.; Walters, K.; Betteridge, P.; Teverson, D.; Taylor, J. St. Paul, Minn. : APS Press; 1991 Nov. Molecular plant-microbe interactions : MPMI v. 4 (6): p. 553-562; 1991 Nov. Includes references. Language: English Descriptors: Phaseolus vulgaris; Pseudomonas; Pathotypes; Pseudomonas syringae pv. phaseolicola; Physiological races; Host specificity; Cultivars; Varietal susceptibility; Virulence; Phenotypes; Genes; Insertional mutagenesis; Gene expression; Amino acid sequences; Nucleotide sequences 116 NAL Call. No.: 448.3 AP5 Genetic analysis of the antifungal activity of a soilborne Pseudomonas aureofaciens strain. Vincent, M.N.; Harrison, L.A.; Brackin, J.M.; Kovacevich, P.A.; Mukerji, P.; Weller, D.M.; Pierson, E.A. Washington, D.C. : American Society for Microbiology; 1991 Oct. Applied and environmental microbiology v. 57 (10): p. 2928-2934; 1991 Oct. Includes references. Language: English Descriptors: Pseudomonas; Biological control agents; Cosmids; Genetic analysis; Antifungal properties; Gaeumannomyces graminis; Rhizoctonia solani; Pythium ultimum Abstract: Pseudomonas aureofaciens Q2-87 produces the antibiotic 2,4-diacetophloroglucinol (Phl), which inhibits Gaeumannomyces graminis var. tritici and other fungi in vitro. Strain Q2-87 also provides biological control of take-all, a root disease of wheat caused by this fungus. To assess the role of Phl in the antifungal activity of strain Q2-87, a genetic analysis of antibiotic production was conducted. Two mutants of Q2-87 with altered antifungal activity were isolated by site-directed mutagenesis with Tn5. One mutant, Q2-87::TN5-1, did not inhibit G. graminis var. tritici in vitro and did not produce Phl. Two cosmids were isolated from a genomic library of the wild-type strain by probing with the mutant genomic fragment. Antifungal activity and Phl production were coordinately restored in Q2-87::Tn5-1 by complementation with either cosmid. Mobilization of one of these cosmids into two heterologous Pseudomonas strains conferred the ability to synthesize Phl and increased their activity against G. graminis var. tritici, Pythium ultimum, and Rhizoctonia solani in vitro. Subcloning and deletion analysis of these cosmids identified a 4.8-kb region which was necessary for Phl synthesis and antifungal activity. 117 NAL Call. No.: 448.3 J82 Genetic and biochemical characterization of a Pseudomonas solanacearum gene cluster required for extracellular polysaccharide production and for virulence. Cook, D.; Sequeira, L. Washington, D.C. : American Society for Microbiology; 1991 Mar. Journal of bacteriology v. 173 (5): p. 1654-1662; 1991 Mar. Includes references. Language: English Descriptors: Pseudomonas solanacearum; Plasmids; Strains; Biochemistry; Gene expression; Genetic engineering; Genetic transformation; Mutagenesis; Polysaccharides; Virulence Abstract: Infection of host plants by Pseudomonas solanacearum results in wilting, which is thought to be due largely to the occlusion of xylem vessels by the P. solanacearum extracellular polysaccharide (EPS) that primarily consists of N-acetylgalactosamine (GAlNAc). By means of Tn3 mutagenesis, we identified a 6.5-kb gene cluster that contains five complementation units required for EPS production and virulence in this bacterium. There was positive correlation between the amount of EPS produced in culture and (i) in planta growth and (ii) virulence. Based on analysis of beta- glucuronidase-gene fusions, these genes are expressed both in broth cultures and in planta and may be constitutive. Both wild-type and mutant strains contained similar amounts of UDP- GAlNAc, the predicted primary substrate for EPS synthesis. Thus, the EPS mutants we obtained should be useful in the analysis of steps in the assembly of the polysaccharide and how this process is related to virulence. 118 NAL Call. No.: 442.8 J8224 Genetic and functional analysis of the basic replicon of pPS10, a plasmid specific for Pseudomonas isolated from Pseudomonas syringae pathovar savastanoi. Nieto, C.; Giraldo, R.; Fernandez-Tresguerres, E.; Diaz, R. London : Academic Press; 1992 Jan20. Journal of molecular biology v. 223 (2): p. 415-426; 1992 Jan20. Includes references. Language: English Descriptors: Pseudomonas syringae pv. savastanoi; Genetic analysis; Nucleotide sequences; Dna; Plasmids; Dna replication; Genes; Comparisons; Host range Abstract: The sequence of a 1823 base-pair region containing the replication functions of pPS10, a narrow host-range plasmid isolated from a strain of Pseudomonas savastanoi, is reported. The origin of replication, oriV, or pPS10 is contained in a 535 fragment of this sequence that can replicate in the presence of function(s) of the plasmid, oriV contains four of 22 base-pairs that are preceded by G + C-rich and A + T-rich regions. A dnaA box located adjacent to repeats of the origin is dispensable but required for efficient replication of pPS10; A and T are equivalent bases at the 5' end of the box. repA, the gene of a trans-acting replication protein of 26,700 Mr has been identified by genetic and functional analysis. repA is adjacent to the origin of replication and is preceded by the consensus sequences of a typical sigma(70) promoter of Escherichia coli. The RepA protein has been identified, using the minicell system of E. coli, as a polypeptide with an apparent molecular mass of 26,000. A minimal pPS10 replicon has been defined to a continuous 1267 base-pair region of pPS10 that includes the oriV and repA sequences. 119 NAL Call. No.: 442.8 Z34 Genetic and molecular analysis of a cluster of rpf genes involved in positive regulation of synthesis of extracellular enzymes and polysaccharides in Xanthomonas campestris pathover campestris. Tang, J.L.; Liu, Y.N.; Barber, C.E.; Dow, J.M.; Wootton, J.C.; Daniels, M.J. Berlin, W. Ger. : Springer International; 1991 May. M G G : Molecular and general genetics v. 226 (3): p. 409-417; 1991 May. Includes references. Language: English Descriptors: Xanthomonas campestris pv. campestris; Genes; Regulation; Protein synthesis; Cellulose; Amylases; O- glycoside hydrolases; Proteinases; Xanthan; Carbohydrate metabolism; Enzyme activity; Cloning; Nucleotide sequences; Induced mutations; Insertional mutagenesis; Transposable elements; Bacterial proteins; Restriction mapping; Pathogenicity; Brassica campestris var. rapa; Amino acid sequences Abstract: The cosmid clone, pIJ3020 containing DNA from the plant pathogenic bacterium Xanthomonas campestris pathovar campestris has previously been shown to complement a non- pathogenic mutant defective in synthesis of extracellular enzymes. The DNA cloned in pIJ3020 was analysed by mutagenesis with Tn5 and Tn5lac and by nucleotide sequencing. The results indicate that this region of the genome contains a cluster of genes, mutation in any of which results in failure of the enzymes and extracellular polysaccharide to be synthesized. The designation rpf (regulation of pathogenicity factors) is proposed for these genes. The nucleotide sequence of one gene (rpfC) predicts a protein product with homology to conserved domains of both sensor and regulator proteins of prokaryotic two-component regulatory systems, which are usually involved in regulating gene expression in response to environmental stimuli. 120 NAL Call. No.: 448.3 J82 Genetic and transcriptional organization of the hrp cluster of Pseudomanas syringae pv. phaseolicola. Rahme, L.G.; Mindrinos, M.N.; Panopoulos, N.J. Washington, D.C. : American Society for Microbiology; 1991 Jan. Journal of bacteriology v. 173 (2): p. 575-586; 1991 Jan. Includes references. Language: English Descriptors: Phaseolus vulgaris; Pseudomonas syringae; Genes; Pathogenicity; Genetic analysis Abstract: The hrp cluster of Pseudomonas syringae pv. phaseolicola encodes functions that are essential for pathogenicity on bean plants and for the elicitation of the hypersensitive response on resistant plants. The cluster was saturated with insertions of transposon Tn3-spice that served both as a mutagen and as a sensitive reporter of the expression of the target regions. The mutations covered a 17.5-kb segment in strain NPS3121, in which seven hrp::Tn5 insertions had been previously mapped, and regions outside this segment. The cluster is organized into seven distinct complementation groups (hrpL, hrpAB, hrpC, hrpD, hrpE, hrpF, and hrpSR) on the basis of the analysis of over 100 Tn3-spice insertions in plasmids and 43 similar insertions in the chromosome; it spans nearly 22 kb and is chromosomally located. The transcriptional orientation of all genes in the cluster was established by measuring the level of ice nucleation activity of complemented merodiploids carrying chromosomal hrp::inaZ fusions after inoculation in Red Kidney bean leaves. Although all seven loci were actively expressed in Red Kidney bean leaves, none of them was substantially expressed when the bacteria were grown in King B broth medium. Mutations in all loci, except those in hrpc, greatly reduced the ability of the bacteria to multiply in bean leaves. Mutations in the hrpC locus, although preventing the bacteria from eliciting a hypersensitive reaction on tobacco, allowed the bacteria to produce delayed and attenuated symptoms in Red Kidney bean leaves and to multiply to a level 10(2)- to 10(3)- fold lower than that of the wild-type strain. This is the first comprehensive report of the genetic and transcriptional organization of the hrp gene cluster in a phytopathogenic bacterium. 121 NAL Call. No.: SB732.6.M65 Genetic evidence that extracellular polysaccharide is a virulence factor of Pseudomonas solanacearum. Denny, T.P.; Baek, S.R. St. Paul, Minn. : APS Press; 1991 Mar. Molecular plant-microbe interactions : MPMI v. 4 (2): p. 198-206; 1991 Mar. Includes references. Language: English Descriptors: Lycopersicon esculentum; Pseudomonas solanacearum; Virulence; Polysaccharides; Mutants; Strains; Strain differences; Genetic analysis; Plasmids; Mutagenesis; Gene expression; Phenotypes; Molecular genetics 122 NAL Call. No.: 448.3 AP5 Genetic iterrelatedness among clover proliferation mycoplasmalike organisms (MLOs) and other MLOs investigated by nucleic acid hybridization and restriction fragment length polymorphism analyses. Lee, I.M.; Davis, R.E.; Hiruki, C. Washington, D.C. : American Society for Microbiology; 1991 Dec. Applied and environmental microbiology v. 57 (12): p. 3565-3569; 1991 Dec. Includes references. Language: English Descriptors: Catharanthus roseus; Mycoplasma-like organisms; Strains; Genetic analysis; Sweet potato witches' broom; Aster yellows Abstract: DNA was isolated from clover proliferation (CP) mycoplasmalike organism (MLO)-diseased periwinkle plants (Catharanthus roseus (L.) G. Don.) and cloned into pSP6 plasmid vectors. CP MLO-specific recombinant DNA clones were biotin labeled and used as probes in dot hybridization and restriction fragment length polymorphism analyses to study the genetic interrelatedness among CP MLO and other MLOs, including potato witches'-broom (PWB) MLO. Results from dot hybridization analyses indicated that both a Maryland strain of aster yellows and a California strain of aster yellows are distantly related to CP MLO. Elm yellows, paulownia witches'- broom, peanut witches'-broom, loofah witches'-broom, and sweet potato witches'-broom may be very distantly related, if at all, to CP MLO. A new Jersey strain of aster yellows MLO, tomato big bud MLO, clover phyllody MLO, beet leafhopper- transmitted virescence MLO, and ash yellows MLO are related to CP MLO, but PWB MLO is the most closely related. Similarity coefficients derived from restriction fragment length polymorphism analyses revealed that PWB and CP MLOs are closely related strains and thus provided direct evidence of their relatedness in contrast to reliance solely on biological characterization. 123 NAL Call. No.: 464.8 P56 Genetic relatedness between two nonculturable mycoplasmalike organisms revealed by nucleic acid hybridization and polymerase chain reaction. Deng, S.; Hiruki, C. St. Paul, Minn. : American Phytopathological Society; 1991 Dec. Phytopathology v. 81 (12): p. 1475-1479; 1991 Dec. Includes references. Language: English Descriptors: Catharanthus roseus; Mycoplasma-like organisms; Comparisons; Genetic analysis; Dna; Phyllody; Aster yellows; Witches' brooms; Restriction fragment length polymorphism; Genetic differences Abstract: Dot-blot hybridization, using nine recombinant plasmids containing clover proliferation (CP) mycoplasmalike organism (MLO) DNA segments, showed that the cloned CP MLO- specific DNA probes hybridized with DNA isolated from CP MLO and potato witches-broom (PWB) MLO-infected periwinkle plants, but not with DNA extracted from healthy periwinkle plants nor from those infected by MLOs associated with clover phyllody (CPD), hydrangea virescence (HV), eastern aster yellows (EAY), and western aster yellows (AY27). Very similar restriction fragment length polymorphism (RFLP) of CP and PWB MLO chromosomal DNA was observed by Southern-blot hybridization using four different CP MLO DNA probes. Similar DNA fragments were amplified when DNAs from CP or PWB MLO-infected plants were used as PCR templates, whereas no DNA fragments were amplified when DNAs from healthy CPD, HV, EAY, and AY27 MLO- infected plants were used as polymerase chain reaction templates. These results suggested that CP and PWB MLO isolates are genetically related, yet distinct from CPD, HV, EAY, and AY27 MLO isolates. 124 NAL Call. No.: SB123.57.M64 Genetic transformation of potato to enhance nutritional value and confer disease resistance. Destefano-Beltran, L.; Nagpala, P.; Jaeho, K.; Dodds, J.H.; Jaynes, J.M. Molecular approaches to crop improvement / edited by E.S. Dennis and D.J. Llewellyn. p. 17-32; 1991. (Plant gene research). Includes references. Language: English Descriptors: Solanum tuberosum; Nicotiana tabacum; Agrobacterium rhizogenes; Genetic transformation; Synthetic genes; Essential amino acids; Protein value; Potatoes; Nucleotide sequences; Amino acid sequences; Gene transfer; Hyalophora cecropia; Proteins; Genes; Antibacterial properties; Antifungal properties; Genetic resistance; Fungal diseases; Plant diseases; Plant pathogenic bacteria 125 NAL Call. No.: QD341.A2N8 Genetic transformation of the plant pathogens Phytophthora capsici and Phytophthora parasitica. Bailey, A.M.; Mena, G.L.; Herrera-Estrella, L. Oxford : IRL Press; 1991 Aug11. Nucleic acids research v. 19 (5): p. 4273-4278; 1991 Aug11. Includes references. Language: English Descriptors: Phytophthora capsici; Phytophthora nicotianae var. parasitica; Genetic transformation; Plasmids; Protoplasts; Bioassays; Pathogenicity Abstract: Phytophthora capsici and P. parasitica were transformed to hygromycin B resistance using plasmids pCM54 and pHL1, which contain the bacterial hygromycin B phosphotransferase gene (hph) fused to promoter elements of the Ustilago maydis heat shock hsp70 gene. Enzymes Driselase and Novozyme 234 were used to generate protoplasts which were then transformed following exposure to plasmid DNA and polyethylene glycol 6000. Transformation frequencies of over 500 transformants per microgram of DNA per 1 X 10(6) protoplasts were obtained. Plasmid pCM54 appears to be transmitted in Phytophthora spp. as an extrachromosomal element through replication, as shown by Southern blot hybridization and by the loss of plasmid methylation. In addition, transformed strains retained their capacity of infecting Serrano pepper seedlings and Mc. Intosh apple fruits, the host plants for P. capsici and P. parasitica, respectively. 126 NAL Call. No.: 448.3 AP5 Genetic transformation system for the fungal soybean pathogen Cercospora kikuchii. Upchurch, R.G.; Ehrenshaft, M.; Walker, D.C.; Sanders, L.A. Washington, D.C. : American Society for Microbiology; 1991 Oct. Applied and environmental microbiology v. 57 (10): p. 2935-2939; 1991 Oct. Includes references. Language: English Descriptors: Glycine max; Cercospora kikuchii; Mutants; Genetic transformation; Strains; Fungicide tolerance; Benomyl; Tubulin; Genes; Genetic markers Abstract: An altered beta-tubulin gene that confers resistance to the fungicide benomyl was isolated from a genomic library of a UV-induced mutant of Cercospora kikuchii and used as a selectable marker for transformation. The level of benomyl resistance conferred to the transformants was at least 150-fold greater than the intrinsic resistance of the C. kikuchii recipient protoplasts. In the majority of cases, the tubulin fragment was integrated at the native beta-tubulin locus, apparently by gene replacement or gene conversion. The frequency of transformation ranged from 0.2 to 6 transformants per microgram of DNA, depending on the recipient strain. Transformation with linearized plasmid resulted in a higher frequency, without changing the type of integration event. Transformants were phenotypically stable after eight consecutive transfers on medium without benomyl. This is the first report of a genetic transformation system for a Cercospora species. 127 NAL Call. No.: 442.8 AN72 Genetical variation for resistance to Alternaria solani in an advanced population of potatoes. Brandolini, A. Warwick : Association of Applied Biologists; 1992 Feb. Annals of applied biology v. 120 (2): p. 353-360; 1992 Feb. Includes references. Language: English Descriptors: Peru; Solanum tuberosum; Alternaria solani; Blight; Clones; Varietal susceptibility; Varietal resistance; Genetic resistance; Genetic variation; Heritability; General combining ability; Earliness; Crop yield 128 NAL Call. No.: SB731.A35 Genetics. Shaw, D.S. London : Academic Press; 1991. Advances in plant pathology v. 7: p. 131-170; 1991. In the series analytic: Phytophthora infestans, the cause of late blight of potato / edited by D.S. Ingram and P.H. Williams. Literature review. Includes references. Language: English Descriptors: Solanum tuberosum; Lycopersicon esculentum; Phytophthora infestans; Virulence; Genes; Inheritance; Metalaxyl; Fungicide tolerance; Genetic analysis; Meiosis; Mitotic recombination; Dna; Molecular genetics; Restriction fragment length polymorphism; Rna; Literature reviews 129 NAL Call. No.: 442.8 Z8 Genetics of leaf blight resistance in wheat. Sinha, B.; Singh, R.M.; Singh, U.P. Berlin, W. Ger. : Springer International; 1991. Theoretical and applied genetics v. 82 (4): p. 399-404; 1991. Includes references. Language: English Descriptors: Triticum aestivum; Alternaria triticina; Genetic resistance; Blight; Epistasis; Crosses; Dominance; Plant breeding; Recurrent selection Abstract: Studies on the genetics of leaf blight caused by Alternaria triticina using generation mean analysis revealed that additive components played a major role, but that dominance components also contributed significantly in controlling the variability for leaf blight resistance in wheat crosses. Furthermore, the additive X additive type of epistasis was predominant in the first three crosses, whereas in the fourth cross additive X dominance (j) and dominance X dominance (1) components of epistasis were most significant. Because of this it may be desirable to follow a simple recurrent selection scheme for higher tolerance, to isolate resistant plants from the segregating populations derived from crosses of parents of diverse origin following the pedigree method of breeding. CPAN-1887 was very tolerant to leaf blight in the present study and should be utilized in hybridization programs to develop leaf-blight-resistant varieties. 130 NAL Call. No.: 448.3 J82 Genetics of xanthan production in Xanthomonas campestris: the xanA and xanB genes are involved in UDP-glucose and GDP- mannose biosynthesis. Koplin, R.; Arnold, W.; Hotte, B.; Simon, R.; Wang, G.; Puhler, A. Washington, D.C. : American Society for Microbiology; 1992 Jan. Journal of bacteriology v. 174 (1): p. 191-199; 1992 Jan. Includes references. Language: English Descriptors: Xanthomonas campestris; Genes; Xanthan; Biosynthesis; Enzymes; Guanosine diphosphate; Udp; Nucleotide sequences; Amino acid sequences; Enzyme activity; Glucose; Mannose Abstract: The nucleotide sequence of a 3.4-kb EcoRI-PstI DNA fragment of Xanthomonas campestris pv. campestris revealed two open reading frames, which were designated xanA and xanB. The genes xanA and xanB encode proteins of 448 amino acids (molecular weight of 48,919) and 466 amino acids (molecular weight of 50,873), respectively. These genes were identified by analyzing insertion mutants which were known to be involved in xanthan production. Specific tests for the activities of enzymes involved in the biosynthesis of UDP-glucose and GDP- mannose indicated that the xanA gene product was involved in the biosynthesis of both glucose 1-phosphate and mannose 1- phosphate. The deduced amino acid sequence of xanB showed a significant degree of homology (59%) to the phosphomannose isomerase of Pseudomonas aeruginosa, a key enzyme in the biosynthesis of alginate. Moreover, biochemical analysis and complementation experiments with the Escherichia coli manA fragment revealed that xanB encoded a bifunctional enzyme, phosphomannose isomerase-GDP-mannose pyrophosphorylase. 131 NAL Call. No.: A00067 Germany--new programme in plant pathology. Schonwitz, R. Paris, France : Biofutur S.A.; 1991 Feb15. European biotechnology newsletter (107): p. 3; 1991 Feb15. Language: English Descriptors: German federal republic; Plant pathology; Research projects; Research support; Biotechnology 132 NAL Call. No.: 500 N21P Global control in Pseudomonas fluorescens mediating antibiotic synthesis and suppression of black root rot of tobacco. Laville, J.; Voisard, C.; Keel, C.; Maurhofer, M.; Defago, G.; Haas, D. Washington, D.C. : The Academy; 1992 Mar01. Proceedings of the National Academy of Sciences of the United States of America v. 89 (5): p. 1562-1566; 1992 Mar01. Includes references. Language: English Descriptors: Nicotiana; Root rots; Ceratocystis paradoxa; Fungus control; Pseudomonas fluorescens; Mutations; Secondary metabolites; Antibiotics; Hydrogen cyanide; Amino acid sequences; Gene mapping; Genetic engineering; Nucleotide sequences Abstract: Pseudomonas fluorescens CHA0 colonizes plant roots, produces several secondary metabolites in stationary growth phase, and suppresses a number of plant diseases, including Thielaviopsis basicola-induced black root rot of tobacco. We discovered that mutations in a P. fluorescens gene named gacA (for global antibiotic and cyanide control) pleiotropically block the production of the secondary metabolites 2,4- diacetylphloroglucinol (Phl), HCN, and pyoluteorin. The gacA mutants of strain CHA0 have a drastically reduced ability to suppress black root rot under gnotobiotic conditions, supporting the previous observations that the antibiotic Phi and HCN individually contribute to the suppression of black root rot. The gacA gene is directly followed by a uvrC gene. Double gacA-uvrC mutations render P. fluorescens sensitive to UV irradiation. The gavA-uvrC cluster is homologous to the orf-2 (= uvrY)-uvrC operon of Escherichia coli. The gacA gene specifies a trans-active 24-kDa protein. Sequence data indicate that the GacA protein is a response regulator in the FixJ/DegU family of two-component regulatory systems. Expression of the gacA gene itself was increased in stationary phase. We propose that GacA, perhaps activated by conditions of restricted growth, functions as a global regulator of secondary metabolism in P. fluorescens. 133 NAL Call. No.: QH426.C8 High efficiency transformation of Fusarium solani f. sp. cucurbitae race 2 (mating population V). Crowhurst, R.N.; Rees-George, J.; Rikkerink, E.H.A.; Templeton, M.D. Berlin, W. Ger. : Springer International; 1992. Current genetics v. 21 (6): p. 463-469; 1992. Includes references. Language: English Descriptors: Fusarium solani; Genetic transformation; Cosmids; Gene transfer; Protoplasts; Direct DNAuptake; Drug resistance; Hygromycin b; Plasmids; Mitosis; Reporter genes Abstract: A cosmid vector, suitable for library construction and DNA transformation in filamentous fungi, has been constructed and a reliable and highly efficient PEG-mediated DNA transformation system for F. solani f. sp. cucurbitae, based on resistance to hygromycin B, has been developed for use with this vector. This transformation system yielded 10(4) transformants per microgram of DNA when using 10(7) protoplasts. Factors important in achieving high efficiency included: the maintenance of an osmoticum in all transformation steps, PEG 4000 concentration, and the ratio of transforming vector DNA to protoplasts. Approximately 60% of transformants stably integrated vector DNA. Molecular analysis revealed multiple copies of the plasmid integrated into the genome at one or more sites. The frequency of transformation achieved will facilitate the isolation of genes from this fungus by complementation. 134 NAL Call. No.: 448.3 J82 High-affinity iron uptake systems present in Erwinia carotovora subsp. carotovora include the hydroxamate siderophore aerobactin. Ishimaru, C.A.; Loper, J.E. Washington, D.C. : American Society for Microbiology; 1992 May. Journal of bacteriology v. 174 (9): p. 2993-3003; 1992 May. Includes references. Language: English Descriptors: Erwinia carotovora subsp. carotovora; Strains; Siderophores; Biosynthesis; Uptake; Genes; Pathogenicity Abstract: The phytopathogenic bacterium Erwinia carotovora subsp. carotovora W3C105 produced the hydroxamate siderophore aerobactin under iron-limiting conditions. A survey of 22 diverse strains of E. carotovora revealed that strain W3C105 alone produced aerobactin. The ferric-aerobactin receptor of strain W3C105 was an 80-kDa protein, identified by immunoblots of Sarkosyl-soluble proteins obtained from E. carotovora cells grown in iron-depleted medium and probed with antiserum raised against the 74-kDa ferric-aerobactin receptor encoded by the pColV-K30 plasmid of Escherichia coli. Genes determining aerobactin biosynthesis and uptake were localized to an 11.3- kb EcoRI-HindIII chromosomal fragment of strain W3C105. A 10- kb subclone of the fragment conferred on E. coli DH5 alpha both aerobactin biosynthesis and uptake, determined by cloacin DF13 sensitivity, the presence of the 80-kDa receptor protein, and iron-independent growth of E. coli clones. The aerobactin biosynthesis genes of E. carotovora W3C105 hybridized to those of the pColV-K30 plasmid of E. coli, but the restriction patterns of the aerobactin regions of E. coli and E.carotovora differed. Although the aerobactin region of enteric bacteria is commonly flanked by Is1-like sequences, IS1 sequences were not detected in the genomic DNA or the cloned aerobactin region of E. carotovora. E. coli DH5 alpha cells harboring cloned aerobactin biosynthesis genes from E. carotovora W3C105 produced greater quantities of aerobactin and the 80-kDa ferric-aerobactin receptor when grown in iron-limited than in iron-replete medium. Strain W3C105 grew on an iron-limited medium, whereas derivatives that lacked a functional aerobactin iron acquisition system did not grow on the medium. These results provide evidence for the occurrence and heterogeneity of aerobactin as a high-affinity iron uptake system of both clinical and phytopathogenic species of the Enterobacteriaceae. Although future studies may reveal a role for aerobactin in 135 NAL Call. No.: QK710.P62 High-level expression of a tobacco chitinase gene in Nicotiana sylvestris. Susceptibility of transgenic plants to Cercospora nicotianae infection. Neuhaus, J.M.; Ahl-Goy, P.; Hinz, U.; Flores, S.; Meins, F. Dordrecht : Kluwer Academic Publishers; 1991 Jan. Plant molecular biology : an international journal on fundamental research and genetic engineering v. 16 (1): p. 141-151. ill; 1991 Jan. Includes references. Language: English Descriptors: Nicotiana tabacum; Nicotiana sylvestris; Cercospora nicotianae; Agrobacterium tumefaciens; Genetic transformation; Transgenics; Chitinase; Genes; Gene expression; Southern blotting; Northern blotting; Disease resistance; Fungal diseases; Leaves; Sds-page; Immunoblotting; Enzyme activity; Beta-glucanase; Ethylene; Regulation Abstract: Endochitinases (E.C. 3.2.14, chitinase) are believed to be important in the biochemical defense of plants against chitin-containing fungal pathogens. We introduced a gene for class I (basic) tobacco chitinase regulated by Cauliflower Mosaic Virus 35S-RNA expression signals into Nicotiana sylvestris. The gene was expressed to give mature, enzymatically active chitinase targeted to the intracellular compartment of leaves. Most transformants accumulated extremely high levels of chitinase-up to 120-fold that of non- transformed plants in comparable tissues. Unexpectedly, some transformants exhibited chitinase levels lower than in non- transformed plants suggesting that the transgene inhibited expression of the homologous host gene. Progeny tests indicate this effect is not permanent. High levels of chitinase in transformants did not substantially increase resistance to the chitin-containing fungus Cercospora nicotiana, which causes Frog Eye disease. Therefore class I chitinase does not appear to be the limiting factor in the defense reaction to this pathogen. 136 NAL Call. No.: 448.3 AP5 Homologous streptomycin resistance gene present among diverse gram-negative bacteria in New York state apple orchards. Norelli, J.L.; Burr, T.J.; Lo Cicero, A.M.; Gilbert, M.T.; Katz, B.H. Washington, D.C. : American Society for Microbiology; 1991 Feb. Applied and environmental microbiology v. 57 (2): p. 486-491. ill; 1991 Feb. Includes references. Language: English Descriptors: New York; Malus pumila; Pseudomonas syringae pv. papulans; Streptomycin; Pesticide resistance; Genes; Dna probes; Dna hybridization; Plasmids; Gram negative bacteria Abstract: The streptomycin resistance gene of Pseudomonas syringae pv. papulans Psp36 was cloned into Escherichia coli and used to develop a 500-bp DNA probe that is specific for streptomycin resistance in P. syringae pv. papulans. The probe is a portion of a 1-kb region shared by three different DNA clones of the resistance gene. In Southern hybridizations, the probe hybridized only with DNA isolated from streptomycin- resistant strains of P. syringae pv. papulans and not with the DNA of streptomycin-sensitive strains. Transposon insertions within the region of DNA shared by the three clones resulted in loss of resistance to streptomycin. Colony hybridization of bacteria isolated from apple leaves and orchard soil indicated that 39% of 398 streptomycin-resistant bacteria contained DNA that hybridized to the probe. These included all strains of P. syringae pv. papulans and some other fluorescent pseudomonads and nonfluorescent gram-negative bacteria, but none of the gram-positive bacteria. The same-size restriction fragments hybridized to the probe in P. syringae pv. papulans. Restriction fragment length polymorphism of this region was occasionally observed in strains of other taxonomic groups of bacteria. In bacteria other than P. syringae pv. papulans, the streptomycin resistance probe hybridized to different-sized plasmids and no relationship between plasmid size and taxonomic group or between plasmid size and orchard type, soil association, or leaf association could be detected. 137 NAL Call. No.: QH442.A1G4 Identification and characterization of the ribosomal RNA- encoding genes in Clavibacter xyli subsp. cynodontis. Sathyamoorthy, M.; Alcorn, S.C.; Lohnas, G.L.; Anderson, J.J.; Uratani, B.B. Amsterdam : Elsevier Science Publishers; 1991. Gene v. 108 (1): p. 47-53; 1991. Includes references. Language: English Descriptors: Clavibacter xyli; Ribosomal RNA; Genes; Ribosomal DNA; Nucleotide sequences; Restriction mapping; Gene mapping; Endophytes; Cynodon dactylon Abstract: Clavibacter xyli subsp. cynodontis (Cxc) is a xylem-inhabiting bacterial endophyte of Bermudagrass. This organism is classified with Gram-positive, high G + C content, coryneform-actinomycete bacteria. Southern-blot analysis showed that Cxc, contains only one copy of the ribosomal RNA- encoding genes (rRNA). A clone containing the rRNA genes was isolated from a genomic library of Cxc DNA cloned in the lambda EMBL3 vector. The gene cluster was partially sequenced, revealing the gene order 5'-16S-23S-5S-3', similar to that found in other prokaryotes. Low-resolution S1 mapping suggested multiple transcription start points of the rRNA operon. 138 NAL Call. No.: 500 N21P Identification of a fungal cutinase promoter that is inducible by a plant signal via a phosphorylated trans-acting factor. Bajar, A.; Krishna Podila, G.; Kolattukudy, P.E. Washington, D.C. : The Academy; 1991 Sep15. Proceedings of the National Academy of Sciences of the United States of America v. 88 (18): p. 8208-8212; 1991 Sep15. Includes references. Language: English Descriptors: Fusarium solani f.sp. pisi; Chloramphenicol acetyltransferase; Cutin; Enzyme activity; Enzyme inhibitors; Gene expression; Growth promoters; Kinases; Phosphorylation; Transcription Abstract: Plant cutin monomers trigger, and glucose suppresses, the expression of the cutinase gene of pathogenic fungi. To identify the cutinase promoter region responsible for induction by the unique plant components, a promoter analysis was done with transformants. Plasmids were constructed that contained (i) the 5' flanking region of the cutinase gene or its deletion mutants from Fusarium solani pisi fused with a chloramphenicol acetyltransferase (CAT) reporter gene and (ii) a constitutive promoter fused with a hygromycin phosphotransferase gene. Hygromycin-resistant transformants of F. solani pisi generated by electroporation were assayed for CAT activity inducible by cutin hydrolysate and for glucose repression of this induction. CAT was induced in a glucose-repressible manner when fused with a 360-base- pair (bp), or longer, segment of the 5' flanking region of the cutinase gene, and deletion of the next 135 bp abolished this induction. Gel retardation assays showed that a protein(s) in nuclear extract from the fungus bound to the 5' flanking region of cutinase gene, and this binding was also abolished when the same 135-bp segment was deleted. These results show that the -225 to -360 segment of the cutinase gene contains a cis-acting regulatory element that binds trans-acting factor(s) in the nuclei. Treatment of the nuclear extract with immobilized phosphatase abolished binding to the promoter, suggesting that binding required a phosphorylated form of the protein. With isolated nuclei, phosphorylation of a protein occurred only in the presence of both cutin monomer and the fungal protein factor. The presence of protein kinase inhibitor H7 during the preincubation of nuclei with the monomer and protein factor inhibited cutinase gene transcription. These results suggest that cutin monomer causes phosphorylation of a transcription factor that binds to the -225 to -360 segment of the cutinase gene and enhances transcription of this gene. 139 NAL Call. No.: 464.8 P56 Identification of a plasmid DNA probe for detection of strains of Erwinia herbicola pathogenic on Gypsophila paniculata. Manulis, S.; Gafni, Y.; Clark, E.; Zutra, D.; Ophir, Y.; Barash, I. St. Paul, Minn. : American Phytopathological Society; 1991 Jan. Phytopathology v. 81 (1): p. 54-57. ill; 1991 Jan. Includes references. Language: English Descriptors: Gypsophila paniculata; Erwinia herbicola; Strains; Pathogenicity; Serotypes; Detection; Dna probes; Plasmids; Immunodiagnosis; Iaa; Biosynthesis Abstract: Pathogenic strains of Erwinia herbicola incite crown and root galls in Gypsophila paniculata. Two serotypic groups were detected in the population of strains isolated from Gypsophila, each of which was composed of pathogens and nonpathogens. An additional isolate of pathogenic E herbicola did not react with serotype I or II. Galls caused by pathogenic serotype I strains varied in morphological appearance from galls of other pathogenic strains. All strains secreted indoleacetic acid (IAA) in culture. No correlation was observed between gall size and the amount of IAA produced in vitro. All strains also contained one to four plasmids with sizes ranging between 10 and 100 MDa. A 7.5-kilobase (kb) DNA fragment was subcloned from a library constructed from plasmid DNA of a pathogenic strain. This DNA fragment cross-hybridized with the sequences encoding the IAA biosynthetic pathway in Pseudomonas savastanoi. The cloned 7.5-kb fragment was used to distinguish among pathogenic and nonpathogenic strains of each serotypic group by blot hybridization experiments. The probe hybridized to 78-MDa plasmids present in pathogenic strains of serotypes I and Ill and to 100-MDa plasmids present in pathogenic strains of serotype II. The relationship between IAA production and the specificity of the probe is discussed. 140 NAL Call. No.: SB732.6.M65 Identification of pathogenicity determinants of Erwinia carotovora subsp. carotovora by transposon mutagenesis. Pirhonen, M.; Saarilahti, H.; Karlsson, M.B.; Palva, E.T. St. Paul, Minn. : APS Press; 1991 May. Molecular plant-microbe interactions : MPMI v. 4 (3): p. 276-283; 1991 May. Includes references. Language: English Descriptors: Nicotiana tabacum; Solanum tuberosum; Erwinia carotovora subsp. carotovora; Virulence; Induced mutations; Mutants; Mutagenesis; Phenotypes; Host parasite relationships; Transposable elements; Transduction; Screening; Assays; Molecular genetics 141 NAL Call. No.: QK725.P532 Identification of Pseudomonas syringae pathogens of Arabidopsis and a bacterial locus determining avirulence on both Arabidopsis and soybean. Whalen, M.C.; Innes, R.W.; Bent, A.F.; Staskawicz, B.J. Rockville, Md. : American Society of Plant Physiologists; 1991 Jan. The Plant cell v. 3 (1): p. 49-59. ill; 1991 Jan. Includes references. Language: English Descriptors: Arabidopsis thaliana; Glycine max; Brassica; Lycopersicon esculentum; Pseudomonas syringae pv. maculicola; Pseudomonas syringae pv. tomato; Pseudomonas syringae pv. glycinea; Loci; Genetic resistance; Virulence; Susceptibility; Disease resistance; Ecotypes; Dna libraries; Cosmids; Leaves; Infections; Ultrastructure Abstract: To develop a model system for molecular genetic analysis of plant-pathogen interactions, we studied the interaction between Arabidopsis thaliana and the bacterial pathogen Pseudomonas syringae pv tomato (Pst). Pst strains were found to be virulent or avirulent on specific Arabidopsis ecotypes, and single ecotypes were resistant to some Pst strains and susceptible to others. In many plant-pathogen interactions, disease resistance is controlled by the simultaneous presence of single plant resistance genes and single pathogen avirulence genes. Therefore, we tested whether avirulence genes in Pst controlled induction of resistance in Arabidopsis. Cosmids that determine avirulence were isolated from Pst genomic libraries, and the Pst avirulence locus avrRpt2 was defined. This allowed us to construct pathogens that differed only by the presence or absence of a single putative avirulence gene. We found that Arabidopsis ecotype Col-0 was susceptible to Pst strain DC3000 but resistant to the same strain carrying avrRpt2, suggesting that a single locus in Col-0 determines resistance. As a first step toward genetically mapping the postulated resistance locus, an ecotype susceptible to infection by DC3000 carrying avrRpt2 was identified. The avrRpt2 locus from Pst was also moved into virulent strains of the soybean pathogen P. syringae pv glycinea to test whether this locus could determine avirulence on soybean. The resulting strains induced a resistant response in a cultivar-specific manner, suggesting that similar resistance mechanisms may function in Arabidopsis and soybean. 142 NAL Call. No.: 448.3 J823 Identification of the exo loci required for exopolysaccharide synthesis in Agrobacterium radiobacter NCIB 11883. Aird, E.L.H.; Brightwell, G.; Jones, M.A.; Johnston, A.W.B. Reading : Society for General Microbiology; 1991 Oct. The Journal of general microbiology v. 137 (pt.10): p. 2287-2297; 1991 Oct. Includes references. Language: English Descriptors: Agrobacterium radiobacter; Mutants; Polysaccharides; Biosynthesis; Rhizobium meliloti; Genes; Loci; Clones; Cosmids; Plasmids; Dna; Gene transfer; Recombination Abstract: We initiated a genetic analysis of Agrobacterium radiobacter NCIB 11883 with particular reference to the (exo) genes required for exopolysaccharide synthesis. Following mutagenesis with nitrosoguanidine, several exo mutant strains were isolated and several of the mutations were corrected by DNA cloned in a newly constructed cosmid library. Analysis of various complementing cosmids by genetic and physical criteria indicated that exo loci were quite widely dispersed in the bacterial genome. Certain exo mutations were corrected by different cosmids that shared no homologous DNA; possible explanations for this are presented. Using phoA fusions, it was shown that some exo genes were, or were closely linked to, genes that specified polypeptides associated with the bacterial cell surface. By introducing the cloned exo genes of Rhizobium meliloti it was found that only one out of thirty exo mutants of A. radiobacter was corrected by a defined exo locus of the former species; further analysis indicated that this particular exo gene corresponded to exoB of R. meliloti. Finally, it was found that several A. radiobacter exo mutants were non-mucoid on media with dicarboxylic acids as sole carbon source but appeared to be wild-type when sugars were the source of carbon. 143 NAL Call. No.: 442.8 Z34 Identification of two fructose transport and phosphorylation pathways in Xanthomonas campestris pv. campestris. Crecy-Lagard, V. de; Lejeune, P.; Bouvet, O.M.M.; Danchin, A. Berlin, W. Ger. : Springer International; 1991 Jul. M G G : Molecular and general genetics v. 227 (3): p. 465-472; 1991 Jul. Includes references. Language: English Descriptors: Xanthomonas campestris pv. campestris; Fructose; Active transport; Phosphotransferases; Insertional mutagenesis; Transposable elements; Cloning; Nucleotide sequences; Amino acid sequences; Restriction mapping; Phosphorylation; Enzyme activity; Induced mutations; Mutants; Fructokinase; Carbohydrate metabolism; Mannose; Sucrose; Mannitol Abstract: Fructose was shown to be phosphorylated by a specific phosphoenolpyruvate-dependent phosphotransferase system (PTS) in Xanthomonas campestris pv. campestris. Transposon mutagenesis of X. campestris was performed and two mutants affected in growth on fructose were isolated. Both mutants were deficient in PTS activity. Comparison of the rate of uptake and phosphorylation of fructose in the wild-type and in the mutant strains revealed the presence of a second fructose permeation and phosphorylation pathway in this bacterium: an unidentified permease coupled to an ATP- dependent fructokinase. One of the two mutants was also deficient in fructokinase activity. Chromosomal DNA fragments containing the regions flanking the transposon insertion site were cloned from both mutant strains. Their physical study revealed that the insertion sites were separated by 1.4 kb, allowing the reconstruction of a wild-type DNA fragment which complemented one of the two mutants. The region flanking the transposon insertion site was sequenced in one of the mutants, showing that the transposon had interrupted the gene encoding the fructose EII. The mutant strains also failed to utilize mannose, sucrose and mannitol, suggesting the existence of a branch point between the metabolism of fructose and of these latter carbohydrates. 144 NAL Call. No.: 470 C16C An immunofluorescent cytochemical technique applying micromanipulation to detect microtubules in plant tissues inoculated with fungal spores. Kobayashi, I.; Kobayashi, Y.; Yamaoka, N.; Kunoh, H. Ottawa, Ont. : National Research Council of Canada; 1991 Dec. Canadian journal of botany; Journal canadien de botanique v. 69 (12): p. 2634-2636; 1991 Dec. Includes references. Language: English Descriptors: Hordeum vulgare; Coleoptiles; Erysiphe pisi; Plant pathogenic fungi; Infectivity; Mycelium; Plant anatomy 145 NAL Call. No.: QH301.N32 In vitro disease resistance for expression of somaclonal variation in Larix. Diner, A.M. New York, N.Y. : Plenum Press; 1991. NATO ASI series : Series A : Life sciences v. 210: p. 63-65; 1991. In the series analytic: Woody plant biotechnology / edited by M.R. Ahuja. Proceedings of a Workshop at the Institute of Forest Genetics, USDA Forest Service, October 15-19, 1989, Placerville, California. Includes references. Language: English Descriptors: Larix decidua; Genotypes; Disease resistance; Cankers; Gremmeniella; Organogenesis; Somaclonal variation 146 NAL Call. No.: QK710.P55 Induction of crown galls by Agrobacterium tumefaciens (strain C58) reverses assimilate translocation and accumulation in Kalanchoe daigremontiana. Malsy, S.; Bel, A.J.E. van; Kluge, M.; Hartung, W.; Ullrich, C.I. Oxford : Blackwell Scientific Publications; 1992 Jun. Plant, cell and environment v. 15 (5): p. 519-529; 1992 Jun. Includes references. Language: English Descriptors: Kalanchoe daigremontiana; Nicotiana tabacum; Agrobacterium tumefaciens; Crown gall; Membrane potential; Plasma membranes; Iaa; Abscisic acid; Source sink relations; Photosynthates; Nutrient transport; Zeatin; Phloem; Sieve plates; Amino acids; Cell suspensions; Genetic transformation; Genes; Dna; Sugars; Nopaline; Phloem loading; Phloem companion cells 147 NAL Call. No.: 64.8 C883 Inheritance of resistance to race 4 of downy mildew derived from interspecific crosses in sunflower. Miller, J.F.; Gulya, T.J. Madison, Wis. : Crop Science Society of America; 1991 Jan. Crop science v. 31 (1): p. 40-43; 1991 Jan. Includes references. Language: English Descriptors: Helianthus annuus; Helianthus; Helianthus argophyllus; Plasmopara halstedii; Inheritance; Genetic resistance; Races; Genes; Dominance; Segregation; Mildews; Wild plants; Lines; Crosses Abstract: Race 4 of downy mildew, incited by Plasmopara halstedii (Farl.) Berl. & de Toni was first reported in sunflower (Helianthus annuus L.) in the USA during 1985. Resistance to this race was found in lines derived from interspecific crosses of cultivated sunflower with three species of wild sunflower. The objectives of this investigation were to determine the genetic control of resistance found in the interspecific crosses and to determine if this resistance was conditioned by the same or different genes. Ratios tested utilizing a chi-square analysis for goodness of fit for F2 and BC1F1 generations indicated that resistance to Race 4 was conditioned by a single, dominant gene in all sources. Four lines (HA 335, HA 336, Charata R4, and Wild Ornamental) were determined to have the same resistance gene Pl6. HA 335 and HA 336 were derived from wild H. annuus 423 and H. annuus 432, respectively. The resistance gene in HA 339, derived from H. praecox Engelm. & Gray ssp. runyonii proved to be different and was designated Pl7. The resistance gene in RHA 340, distinct from Pl6 and Pl7 and derived from H. argophyllus Torrey & Gray, was designated Pl3. Using divergent resistance genes in sunflower commercial hybrids should decrease genetic vulnerability to changes in pathogenicity of downy mildew. However, additional wild species of sunflower should be collected and tested to identify new sources of resistance to downy mildew. 148 NAL Call. No.: 500 N21P Integration and expression of a rabbit liver cytochrome P-450 gene in transgenic Nicotiana tabacum. Saito, K.; Noji, M.; Ohmori, S.; Imai, Y.; Murakoshi, I. Washington, D.C. : The Academy; 1991 Aug15. Proceedings of the National Academy of Sciences of the United States of America v. 88 (16): p. 7041-7045; 1991 Aug15. Includes references. Language: English Descriptors: Nicotiana tabacum; Cytochromes; Gene expression; Genetic transformation; Metabolism; Nucleotide sequences; Phenotypes; Plasmids; Senescence; Transgenics; Agrobacterium tumefaciens Abstract: Cytochrome P-450 is involved in the oxidative metabolism of a broad range of substrates. We have made a chimeric construct, pSN002, containing the cDNA for rabbit liver cytochrome P-450 (IIC14) under the control of the TR2' promoter for mannopine synthase in the Agrobacterium Ti plasmid. Nicotiana tabacum was transformed with Agrobacterium tumefaciens harboring a cointegrated plasmid pSN002::pGV2260. The presence of mRNA and of the translated protein from the chimeric cytochrome P-450 gene in transgenic plants was confirmed by RNA blot hybridization and by Western blot and immunohistochemical analyses, respectively. The transformants in which the foreign cytochrome P-450 protein is expressed show marked phenotypic changes, notably a tendency rapidly to senesce. We detected 2-propenylpyrrolidine, a degradative metabolite of nicotine alkaloids, in transgenic tobacco showing this pronounced phenotypic change. Such metabolism is likely to be due to the effect of senescence and not directly to the presence of the cytochrome P-450. 149 NAL Call. No.: 448.3 J823 Isolation and characterization of behavioural mutants and genes of Agrobacterium tumefaciens. Shaw, C.H.; Loake, G.J.; Brown, A.P.; Garrett, C.S.; Deakin, W.; Alton, G.; Hall, M.; Jones, S.A.; O'Leary, M.; Primavesi, L. Reading : Society for General Microbiology; 1991 Aug. The Journal of general microbiology v. 137 (pt.8): p. 1939-1953; 1991 Aug. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Mutants; Genes; Cosmids; Chemotaxis; Motility; Flagella; Behavior Abstract: Agrobacterium tumefaciens exhibits an unusual flagellation pattern in the electron microscope. The typical pattern is of two flagella in a polar or sub-polar tuft at one pole only, plus one or two lateral flagella on each side. Twenty independent behavioural mutants were isolated, after Tn5 mutagenesis, and divided into several classes. Fourteen non-motile mutants were differentiable into non-flagellate and flagellate subclasses, one non-chemotactic mutant appeared to have a defect in the intracellular signalling pathway, and one other mutant displayed an unusual pattern of polar cell pairing. Four mutants with impaired swarming ability were also isolated. Root colonization ability was impaired in the non- motile mutant for which this property was tested. From all but three of the mutants, the Tn5 insertion sites, including flanking sequences, have been cloned and used as probes to isolate a set of seven cosmids from a wild-type A. tumefaciens library. No hybridization to Escherichia coli or Pseudomonas DNA was detected for the A. tumefaciens mutant flanking sequences, but varying degrees of similarity to Rhizobium meliloti behavioural genes were detected. By complementation of A. tumefaciens behavioural mutants and hybridization of mutant flanking sequences, one cosmid insert was shown to contain at least nine behavioural loci, and another, linked to it on the chromosome, at least three. This suggests that, as in other organisms, behavioural genes are clustered in the A. tumefaciens genome. 150 NAL Call. No.: 464.8 P692 The isolation and characterization of polyclonal and monoclonal antibodies to anastomosis group 8 of Rhizoctonia solani. Matthew, J.S.; Brooker, J.D. Oxford : Blackwell Scientific Publications; 1991 Mar. Plant pathology v. 40 (1): p. 67-77. ill; 1991 Mar. Includes references. Language: English Descriptors: Rhizoctonia solani; Anastomosis groups; Monoclonal antibodies; Immunodiagnosis; Serological relationships; Identification; Cross reaction; Characterization Abstract: Polyclonal and monoclonal antibodies were raised against secreted proteins from an anastomosis group 8 isolate of Rhizoctonia and tested for reactivity to field isolates from anastomosis groups 2-1, 3, 4 and 8, Polyclonal antibodies raised against total secreted proteins cross-reacted in immunoblotting experiments with all R. solani isolates However, immunoreactive proteins specific to Ag-8 isolates were evident. Monoclonal antibodies to secreted proteins were raised which reacted with fewer proteins and showed a greater degree of specificity for AG-8 isolates. Two monoclonals were selected for further study. One, an IgM monoclonal antibody, reacted with all R. solani isolates, recognizing a 40-kDa protein specific to AG-8 isolates and proteins of lower molecular weight in isolates from other anastomosis groups. The other, an IgG monoclonal antibody, was more specific, reacting with 38-, 40-and 55-kDa proteins from AG-8 isolates and cross-reacting, with few isolates from other anastomosis groups. Preliminary results on the induction of antigens recognized by the monoclonal antibodies are presented. The monoclonal antibodies characterized here are useful for the identification of isolates of R. solani and may also be used as probes to clarify the relationships between anastomosis groups. 151 NAL Call. No.: SB732.6.M65 Isolation and gene disruption of the Tox5 gene encoding trichodiene synthase in Gibberella pulicaris. Hohn, T.M.; Desjardins, A.E. St. Paul, Minn. : APS Press; 1992 May. Molecular plant-microbe interactions : MPMI v. 5 (3): p. 249-256; 1992 May. Includes references. Language: English Descriptors: Solanum tuberosum; Gibberella pulicaris; Genes; Trichothecenes; Biosynthesis; Ligases; Inhibition; Genetic analysis; Plant pathogenic fungi; Genetic transformation; Plasmids; Mutants; Strains; Phenotypes; Nucleotide sequences; Amino acid sequences; Comparisons; Fusarium sporotrichioides 152 NAL Call. No.: QH426.C8 Isolation, characterization and sequence of a gene conferring resistance to the systemic fungicide carboxin from the maize smut pathogen, Ustilago maydis. Keon, J.P.R.; White, G.A.; Hargreaves, J.A. Berlin, W. Ger. : Springer International; 1991. Current genetics v. 19 (6): p. 475-481; 1991. Includes references. Language: English Descriptors: Ustilago zeae; Zea mays; Genetic code; Carboxin; Resistance; Nucleotide sequences; Amino acid sequences; Plant pathogenic fungi; Genetic transformation; Genetic markers; Mutants; Gene expression; Plasmids; Gene mapping Abstract: A gene which confers resistance to the systemic fungicide carboxin (Cbx) has been isolated from the maize pathogen, Ustilago maydis, by transferring a plasmid gene library from a Cbx-resistant mutant strain into a sensitive strain and selecting for expression of the resistance gene. Five plasmids, rescued from transformants which exhibited enhanced resistance to Cbx, were shown to have DNA inserts with common restriction enzyme fragments. All the plasmids transformed a sensitive U. maydis strain to Cbx resistance. The gene (Cbx(r)), sub-cloned on a 3.2 kb EcoR1-HindIII fragment, transformed U. maydis to Cbx resistance at frequencies similar to those obtained with the bacterial Hygromycin B resistance (HygB(r)) gene. The sequence of the Cbx(r) gene showed a high degree of homology to succinate dehydrogenase (EC 1.3.99.1) iron-sulphur subunit genes from other organisms. 153 NAL Call. No.: 448.3 J823 Isolation of a benomyl-resistant allele of the beta-tubulin gene from Septoria nodorum and its use as a dominant selectable marker. Cooley, R.N.; Gorcom, R.F.M. van; Hondel, C.A.M.J.J. van den; Caten, C.E. Reading : Society for General Microbiology; 1991 Sep. The Journal of general microbiology v. 137 (pt.9): p. 2085-2091; 1991 Sep. Includes references. Language: English Descriptors: Leptosphaeria nodorum; Mutants; Tubulin; Genes; Benomyl; Fungicide tolerance; Pathogenesis; Marker genes; Genetic transformation; Cosmids; Clones Abstract: We have developed a homologous transformation system for the wheat-pathogenic fungus Septoria nodorum based on a benomyl-(MBC-) resistant allele of the beta-tubulin gene. The beta-tubulin gene was isolated by heterologous hybridization from a cosmid library prepared from an MBC- resistant mutant. Cosmids carrying the gene conferred MBC resistance when introduced into a sensitive strain, demonstrating that resistance to MBC fungicides in S. nodorum may be determined by the beta-tubulin gene. This MBC resistant allele of the P-tubulin gene (tuba R) was subcloned into pUC18 and used as a dominant selectable marker for transformation of wild-type sensitive strains. Transformants arose at frequencies of approximately 5 per pg of DNA, were integrative in nature and were mitotically stable. Some transformants showed a marked reduction in vigour, both in the presence and absence of MBC; this is thought to arise from overproduction of beta-tubulin. The S. nodorum tubA R gene also conferred MBC resistance on the related species Leptosphaeria maculans, a pathogen of Brassica, following its introduction by cotransformation. Probing digested SL nodorum DNA with tubA R at low stringency revealed only a single P-tubulin gene. We anticipate that tubA R will prove a useful tool for the investigation of the pathogenicity of S. nodorum and other fungi. 154 NAL Call. No.: SB732.6.M65 Isolation of a gene cluster from Xanthomonas campestris pv. vesicatoria that determines pathogenicity and the hypersensitive response on pepper and tomato. Bonas, U.; Schulte, R.; Fenselau, S.; Minsavage, G.V.; Staskawicz, B.J.; Stall, R.E. St. Paul, Minn. : APS Press; 1991 Jan. Molecular plant-microbe interactions : MPMI v. 4 (1): p. 81-88; 1991 Jan. Includes references. Language: English Descriptors: Lycopersicon esculentum; Capsicum annuum; Disease resistance; Xanthomonas campestris pv. vesicatoria; Pathogenicity; Genetic analysis; Insertional mutagenesis; Genes; Complementation; Pathotypes; Comparisons; Xanthomonas campestris 155 NAL Call. No.: 448.3 J82 The lemA gene required for pathogenicity of Pseudomonas syringae pv. syringae on bean is a member of a family of two- component regulators. Hrabak, E.M.; Willis, D.K. Washington, D.C. : American Society for Microbiology; 1992 May. Journal of bacteriology v. 174 (9): p. 3011-3020; 1992 May. Includes references. Language: English Descriptors: Pseudomonas syringae pv. syringae; Pathogenicity; Genes; Nucleotide sequences; Amino acid sequences; Phaseolus vulgaris Abstract: The lemA gene of the plant pathogen Pseudomonas syringae pv. syringae is required for disease lesion formation on bean plants. Cosmid clones that complemented a lemA mutant in trans were isolated previously. The lemA gene was localized by subcloning and transposon mutagenesis. The lemA region and flanking DNA were sequenced, and an open reading frame of 2.7 kb was identified. The nucleotide and predicted amino acid sequences of the lemA gene showed sequence similarity to a family of prokaryotic two-component regulatory proteins. Unlike most of the previously described two-component systems, the lemA gene product contained homology to both components in one protein. Mutations introduced upstream and downstream of the lemA gene failed to locate a gene for a second protein component but identified the putative cysM gene of P. syringae pv. syringae. The cysM gene was located upstream of the lemA gene and was divergently transcribed. The lemA gene product was expressed at low levels in P. syringae pv. syringae and appeared to be positively auto-regulated. 156 NAL Call. No.: SB732.6.M65 Limited host range Ti plasmids: recent origin from wide host range Ti plasmids and involvement of a novel IS element, IS868. Paulus, F.; Canaday, J.; Otten, L. St. Paul, Minn. : APS Press; 1991 Mar. Molecular plant-microbe interactions : MPMI v. 4 (2): p. 190-197; 1991 Mar. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Biotypes; Strains; Strain differences; Tumors; Plasmids; Host range; Genetic analysis; Nucleotide sequences; Amino acid sequences; Insertional mutagenesis; Comparisons; Pseudomonas syringae pv. savastanoi; Pathogenicity 157 NAL Call. No.: QH426.C8 Linear DNA plasmids of the perennial ryegrass choke pathogen, Epichloe typhina (Clavicipitaceae). Mogen, K.L.; Siegel, M.R.; Schardl, C.L. Berlin, W. Ger. : Springer International; 1991. Current genetics v. 20 (6): p. 519-526; 1991. Includes references. Language: English Descriptors: Acremonium coenophialum; Acremonium; Claviceps purpurea; Clavicipitales; Mitochondrial DNA; Dna; Plasmids; Restriction mapping; Nucleotide sequences Abstract: Epichloe typhina is a clavicipitaceous ascomycete which systemically infects grasses, causes choke disease of host inflorescences, and is related to a group of mutualistic grass endophytes. Three plasmids of 7.5, 2.1 and 2.0 kilobase pairs were found in mitochondrial DNA preparations of an E. typhina isolate from perennial ryegrass (Lolium perenne). Results of nuclease digestion indicated that the plasmids, designated Et7.5L, Et2.1L, and ET2.0L, were linear, double- stranded DNAs with protein linked to their 5'-ends (plDNA). The plasmids shared little or no homology with each other, and were not integrated into the mitochondrial or nuclear genomes. No homologous plasmids were detected in isolates of E. typhina from other grass hosts, anamorphic endophytes, or other Clavicipitaceae. However, other plasmids were present in Balansia obtecta and Claviceps purpurea. A partial sequence of one of the E. typhina plasmids, ET2.0L, indicated an open reading frame when UGA was assumed to encode tryptophan. The inferred amino acid sequence had 24% identity over 258 amino acids in two regions of the reverse transcriptase encoded by the circular Mauriceville and Varkud plasmids of Neurospora spp. The homologies included six segments conserved in RNA template-dependent DNA or RNA polymerases. 158 NAL Call. No.: QH426.C8 Linear, non-mitochondrial plasmids of Alternaria alternata. Shepherd, H.S. Berlin, W. Ger. : Springer International; 1992. Current genetics v. 21 (2): p. 169-172; 1992. Includes references. Language: English Descriptors: Alternaria alternata; Plasmids; Mitochondria Abstract: Three plasmids, with sizes of 7.0 kbp, 6.8 kbp, and 5.0 kbp and designated pAal-1, pAal-2 and pAal-3 respectively, have been found in a tentoxin-producing isolate of Alternaria alternata. Exonuclease digestions show these plasmids to be linear with blocked 5' ends. Plasmid pAal-1 does not hybridize to nuclear DNA, mitochondrial DNA, or double-stranded RNA from a mycovirus found in the isolate, but does hybridize weakly to a series of linear DNAs which are not visible on gels and may include pAal-2 and pAal-3. Cellular fractionation shows that, unlike other linear fungal plasmids, these plasmids are not localized in the mitochondria. Plasmids have not been found in other tentoxin-producing isolates and there is no evidence that these plasmids have any effect on the production of tentoxin. 159 NAL Call. No.: 442.8 Z34 Localization and orientation of the VirD4 protein of Agrobacterium tumefaciens in the cell membrane. Okamoto, S.; Toyoda-Yamamoto, A.; Ito, K.; Takebe, I.; Machida, Y. Berlin, W. Ger. : Springer International; 1991 Aug. M G G : Molecular and general genetics v. 228 (1/2): p. 24-32; 1991 Aug. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Bacterial proteins; Spatial distribution; Cell membranes; Genes; Crown gall; Genetic engineering; Alkaline phosphatase; Marker genes Abstract: The virD4 gene of Agrobacterium tumefaciens is essential for the formation of crown galls. Analysis of the nucleotide sequence of virD4 has suggested that the N-terminal region of the encoded protein acts as a signal peptide for the transport of the VirD4 protein to the cell membrane of Agrobacterium. We have examined the localization and orientation of this protein in the cell membrane. When the nucleotides encoding the first 30 to 41 amino acids from the N-terminus of the VirD4 protein were fused to the gene for alkaline phosphatase from which the signal sequence had been removed, alkaline phosphatase activity was detectable under appropriate conditions. Immunoblotting with VirD4-specific antiserum indicated that the VirD4 protein could be recovered exclusively from the membrane fraction of Agrobacterium cells. Moreover, when the membrane fraction was separated into inner and outer membrane fractions by sucrose density-gradient centrifugation, VirD4 protein was detected in the inner- membrane fraction and in fractions that sedimented between the inner and outer membrane fractions. By contrast, the VirD4'/'alkaline phosphatase fusion protein with the N- terminal sequence from VirD4 was detected only in the inner membrane fraction. Treatment of spheroplasts of Agrobacterium cells with proteinase K resulted in digestion of the VirD4 protein. These results indicate that the VirD4 protein is transported to the bacterial membrane and anchored on the inner membrane by its N-terminal region. In addition, the C- terminal portion of the VirD4 protein probably protrudes into the periplasmic space, perhaps in association with some unidentified cellular factor(s). 160 NAL Call. No.: SB599.P45 Localization of carbohydrate antigens in the walls of Phytophthora megasperma f.sp. glycinea by monoclonal antibodies. Wycoff, K.L.; Ayers, A.R. London : Academic Press; 1991 Aug. Physiological and molecular plant pathology v. 39 (2): p. 95-109; 1991 Aug. Includes references. Language: English Descriptors: Glycine max; Host parasite relationships; Phytophthora megasperma; Cell walls; Hyphae; Cell wall components; Beta-glucan; Fungal antigens; Monoclonal antibodies; Immunological techniques; Immunofluorescence; Molecular biology Abstract: A set of five carbohydrate-specific monoclonal antibodies (mAbs) were used to probe the ultrastructure of the walls of the soybean pathogen Phytophthora megasperma f.sp. glycinea, using a combination of immunofluorescence and immuno-gold labelling techniques. Results with beta-1,3 glucan-specific antibodies suggest that beta-1,3 glucans are present throughout the walls of both germ tubes and cysts, but are more prevalent in the outer portion. In addition, beta-1,3 glucans on the surface of hyphal walls, but not cysts, are closely associated with other material, most likely protein, that sterically hinders antibody binding except to non- reducing terminal residues. An antibody whose epitope involved both beta-1,4 and beta-1,3 glucosyl linkages bound predominantly to the inner portion of the hyphal wall. However, fluorescent labelling with this antibody suggested that beta-1,4 linkages are present on the exterior of P. megasperma f.sp glycinea walls as well. Staining with another antibody indicates that changes in wall composition occur over 50-100 micrometers from the hyphal tip, a greater distance than previously supposed. The role of the antigens recognized by these mAbs in the plant-pathogen interaction is not known, but potential uses of these and other mAbs are discussed. 161 NAL Call. No.: 448.3 J823 Localization of transposon insertions in pathogenicity mutants of Erwinia amylovora and their biochemical characterization. Bellemann, P.; Geider, K. Reading : Society for General Microbiology; 1992 May. The Journal of general microbiology v. 138 (pt.5): p. 931-940; 1992 May. Includes references. Language: English Descriptors: Pyrus communis; Blight; Bacteriophages; Erwinia amylovora; Mutants; Transposable elements; Plasmids; Insertional mutagenesis; Cosmids; Complementation; Virulence; Symptoms Abstract: Transposon Tn5, on a mobilizable ColE1 plasmid, on a Ti plasmid derepressed for bacterial transfer, and on the bacteriophage fd genome, was used to construct pathogenicity mutants of the fire blight pathogen Erwinia amylovora. Eleven nonpathogenic mutants were isolated from 1600 independent mutants screened. These mutants were divided into three types: auxotrophs, exopolysaccharide (EPS)-deficient mutants and a mutant of the dsp phenotype. According to their insertion sites the Tn5 mutants were mapped into several classes. Some of the mutants could be complemented with cosmid clones from a genomic library of the parent strain for EPS production on minimal agar. EPS-deficient mutants and the dsp mutant could complement each other to produce virulence symptoms on pear slices. 162 NAL Call. No.: 448.3 J82 Location and cloning of the ketal pyruvate transferase gene of Xanthomonas campestris. Marzocca, M.P.; Harding, N.E.; Petroni, E.A.; Cleary, J.M.; Ielpi, L. Washington, D.C. : American Society for Microbiology; 1991 Dec. Journal of bacteriology v. 173 (23): p. 7519-7524; 1991 Dec. Includes references. Language: English Descriptors: Xanthomonas campestris; Genes; Transferases; Pyruvic acid; Cloning; Gene expression; Xanthan; Biosynthesis Abstract: Genes required for xanthan polysaccharide synthesis (xps) are clustered in a DNA region of 13.5 kb in the chromosome of Xanthomonas campestris. Plasmid pCHC3 containing a 12.4-kb insert of xps genes has been suggested to include a gene involved in the pyruvylation of xanthan gum (N. E. Harding, J. M. Clearn, D. K. Cabanas, I. G. Rosen, and K. S. Kang, J. Bacteriol. 169:2854-2861, 1987). An essential step toward understanding the biosynthesis of xanthan gum and to enable genetic manipulation of xanthan structure is the determination of the biochemical function encoded by the xps genes. On the basis of biochemical characterization of an X. campestris mutant which produces pyruvate-free xanthan gum, complementation studies, and heterologous expression, we have identified the gene coding for the ketal pyruvate transferase (kpt) enzyme. This gene was located on a 1.4-kb BamHI fragment of pCHC3 and cloned in the broad-host-range cloning vector PRK404. An X. campestris kpt mutant was constructed by mini- Mu(Tetr) mutagenesis of the cloned gene and then by recombination of the mutation into the chromosome of the wild- type strain. 163 NAL Call. No.: 500 N21P Mechanism of phenolic activation of Agrobacterium virulence genes: development of a specific inhibitor of bacterial sensor/response systems. Hess, K.M.; Dudley, M.W.; Lynn, D.G.; Joerger, R.D.; Binns, A.N. Washington, D.C. : The Academy; 1991 Sep01. Proceedings of the National Academy of Sciences of the United States of America v. 88 (17): p. 7854-7858; 1991 Sep01. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Crown gall; Gene expression; Glycosides; Phenols; Plasmids; Virulence Abstract: The aglycone of the dihydrodiconiferyl alcohol glycosides, a series of phenolic growth factors able to substitute for some of the hormone requirements of tobacco cell division, are also potent inducers of virulence gene expression in Agrobacterium tumefaciens. However, these factors do not conform to the previously established structural requirements necessary for vir expression. Systematic evaluation of the structural requirements of these inducers has led to a model detailing the role of the phenolics in induction. With this model, a specific inhibitor of vir induction has been developed. This inhibitor does not affect the induction of other genes on the Ti plasmid but irreversibly blocks vir expression. The inhibitor has been used to show that the inducing phenolics must be constantly present to maintain expression of the vir regulon. 164 NAL Call. No.: QH426.C8 Meiotic and mitotic stability of transforming DNA in the phytopathogenic fungus Magnaporthe grisea. Tooley, P.W.; Leung, H.; Leong, S.A. Berlin, W. Ger. : Springer International; 1992. Current genetics v. 21 (1): p. 55-60; 1992. Includes references. Language: English Descriptors: Magnaporthe grisea; Genetic transformation; Dna; Stability; Meiosis; Mitosis; Genetic markers; Segregation; Hygromycin b; Drug resistance; Phosphotransferases; Plasmids; Recombination; Virulence; Fungal diseases; Oryza sativa; Eragrostis curvula Abstract: Magnaporthe grisea was transformed with cosmid pAN7-2 encoding hygromycin B resistance but containing no homology with the M. grisea genome. Rearrangement of the integrated DNA was detected in several hygromycin B-resistant progeny from cross Guy11-T10-1 (a single-copy integration site transformant) X 2539 sensitive wild-type parent), but not in hygromycin B-resistant progeny from four other crosses. Transformants produced typical lesions when inoculated onto host plants. Southern hybridization revealed rearrangements of integrated DNA in single conidial isolates of high-copy transformant 2539-T1-1 re-isolated from host plants, characterized by excision of one or more copies of the transforming plasmid. Plasmid loss and rearrangement were also observed within single conidial isolates derived from transformant 2539-T1-1 following ten asexual generations on non-selective agar medium. These examples of instability of integrated DNA in M. grisea transformants suggest that caution should be exercised in the use of transformation for assessing the phenotypic effects of specific introduced genes. 165 NAL Call. No.: 464.8 P56 A method for genetic analysis of Glomerella graminicola (Colletotrichum graminicola) from maize. Vaillancourt, L.J.; Hanau, R.M. St. Paul, Minn. : American Phytopathological Society; 1991 May. Phytopathology v. 81 (5): p. 530-534. ill; 1991 May. Includes references. Language: English Descriptors: Zea mays; Infection; Colletotrichum graminicola; Strains; Mating; Ascospores; Progeny; Recombination; Segregation; Markers; Crosses; Mutants; Gene transfer; Genetic analysis Abstract: Strains derived from nine different isolates of Colletotrichum graminicola from maize participated in the production of perithecia when incubated on pieces of autoclaved corn leaves in a humidity chamber. Matings occurred between self-fertile and self-sterile strains, and also between certain self-sterile strains. As many as 200 ascospore progeny were recovered easily from individual perithecia. Characterization of progeny showed that sexual recombination and Mendelian segregation of distinct traits could be detected. Segregation of markers for chlorate resistance (ChlR), benomyl resistance (BmlR), and melanin deficiency (Mel-) approximated a 1:1 ratio and defined three separate linkage groups. Crosses involving a pyrimidine auxotroph (Pyr- ) showed 2:1 segregation (Pyr+:Pyr-) and linkage between markers for Pyr- and ChlR. Attempts to combine multiple markers resulted in successful construction of a Mel- Pyr- self-fertile strain that was crossed with a BmlR strain to produce offspring with a triple-mutant Mel- Pyr- BmlR phenotype. 166 NAL Call. No.: QK710.P62 Mismatch-specific DNA breakdown in nuclear extract from tobacco (Nicotiana tabacum) callus. Cerovic, G.; Bozin, D.; Dimitrijevic, B. Dordrecht : Kluwer Academic Publishers; 1991 Oct. Plant molecular biology : an international journal on molecular biology, biochemistry and genetic engineering v. 17 (4): p. 887-894; 1991 Oct. Includes references. Language: English Descriptors: Nicotiana tabacum; Agrobacterium tumefaciens; Dna repair; Nucleotide sequences; Dna modification; Degradation; Enzyme activity; Deoxyribonuclease i; Nuclei; Callus; Genetic transformation; Crown gall Abstract: Mismatch-specific enzymatic activity was sought for in nuclei from normal and transformed plant cells originating from tobacco (Nicotiana tabacum) callus and crown gall tumor induced by Agrobacterium tumefaciens. The specific enzymatic activity was assayed with substrates derived from synthetic oligonucleotides (19-mer sequences corresponding to the human K-ras gene). Single-base changes in the middle of the sequence were the basis for creating heteroduplexes with all eight mismatches. Homo- and heteroduplexes were ligated in a size ladder and used as substrates. We detected mismatch-specific DNA breakdown and determined basic requirements for the reactions. Kinetic analysis indicates the following reactivity order of preference: C: A = C: C = C: T > G: T approximately A: A approximately G: A approximately G: G approximately T: T > > G: C. It can be said now that specific mismatch recognition and repair activities have been detected in all kingdoms of living species. 167 NAL Call. No.: QH426.C8 Mitotic stability of transforming DNA is determined by its chromosomal configuration in the fungus Cochliobolus heterostrophus. Keller, N.P.; Bergstrom, G.C.; Yoder, O.C. Berlin, W. Ger. : Springer International; 1991. Current genetics v. 19 (3): p. 227-233; 1991. Includes references. Language: English Descriptors: Cochliobolus heterostrophus; Genetic transformation; Dna; Stability; Mitosis; Plasmids; Dna methylation; Deletions; Homologous recombination; Chromosomes; Pathogenesis; Fungal diseases; Zea mays Abstract: Cochliobolus heterostrophus was transformed with a plasmid (pH1S) containing a bacterial gene (hygB), which confers resistance to the antibiotic hygromycin B when under control of an 838-bp fragment of promoter 1 from C. heterostrophus. The plasmid integrated at either homologous (52% single copy, 33% tandemly repeated copies) or ectopic (4% single copy, 11% tandemly repeated copies) sites on different chromosomes, resulting in four distinct configurations of integrated DNA. All four configurations were highly stable during mitotic growth; virtually no loss of integrated DNA was detected after five subcultures on nonselective medium or after seven cycles of pathogenesis on maize, the normal host of this fungus. However, deletion of integrated DNA was detected after eight or more disease cycles. The frequency of deletion depended on the configuration of the recombinant chromosome. A single copy of pH1S integrated at an homologous site was flanked by direct repeats of the target sequence and was least stable; up to 50% of the population lacked integrated DNA after 12 disease cycles. A single copy integrated at an ectopic site had no repeated DNA directly associated with it and was the most stable; no deletions were detected after 12 disease cycles. Tandemly repeated copies of pH1S integrated at either homologous or ectopic sites appeared to have intermediate stability; 2-18% of each population lost at least one copy after 12 disease cycles, although in no case were all copies deleted. Cytosine residues of integrated DNA were methylated during mitotic growth, but this had no apparent effect on the expression of hygB. 168 NAL Call. No.: QH431.A1G43 Mobilization of Agrobacterium rhizogenes root-inducing plasmids into the cells of Rhizobium meliloti, Rhizobium galegae, and Rhizobium leguminosarum biovar trifolii. Novikova, N.I.; Pavlova, E.A.; Safronova, V.I.; Zabelina, N.K. New York, N.Y. : Consultants Bureau; 1991 Aug. Soviet genetics v. 27 (2): p. 154-161; 1991 Aug. Translated from: Genetika, v. 27 (2), 1991, p. 229-237. (QH431.A1G4). Includes references. Language: English; Russian Descriptors: Agrobacterium rhizogenes; Rhizobium meliloti; Rhizobium leguminosarum; Rhizobium trifolii; Rhizobium; Plasmids; Genetic transformation; Nodulation; Roots; Growth; Virulence; Nitrogen fixation; Nicotiana tabacum; Medicago sativa; Galega; Plant disorders Abstract: Root-inducing plasmids (pRi) of two Agrobacterium rhizogenes strains were marked with transposon Tn5-mob. Using plasmid RP4-4 the pRi::tn5-mob were mobilized with a frequency of 10(-6)-10(-7) into the cells of the nodule bacteria of Medicago, Trifolium, and Galega. The transconjugants of the Trifolium and Galega nodule bacteria stimulated the proliferation of "hairy roots" on tobacco leaves, while the transconjugants of Rhizobium meliloti (pRi) were nonpathogenic, actively fixed nitrogen in symbiosis with alfalfa, and were more virulent than the initial recipient strain. The presence of pRi in the cells of Galega nodule bacteria led to a reduction in the number of nodules formed by them on the roots of the host plant. In the inoculated clover plants the rate of nodulation did not change, but three weeks after the day of inoculation with recombinant strains we observed inhibition of the level of acetylene reductase activity, leading ultimately to development of inefficient symbiosis. 169 NAL Call. No.: 464.8 P566 Molecular and cellular aspects of Dutch elm disease. Sticklen, M.B.; Bolyard, M.G.; Hajela, R.K.; Duchesne, L.C. Saint-Hyacinthe : Quebec Society for the Protection of Plants; 1991. Phytoprotection v. 72 (1): p. 1-13; 1991. Literature review. Includes references. Language: English Descriptors: Ulmus Americana; Ceratocystis ulmi; Fungal diseases; Mycotoxins; Phytotoxicity; Pathogenesis; Molecular biology; Molecular genetics; Defense mechanisms; Literature reviews; Fungal antagonists; Disease resistance; Scolytidae; Disease vectors 170 NAL Call. No.: 464.8 AN72 Molecular and genetic analysis of toxin production by pathovars of Pseudomonas syringae. Gross, D.C. Palo Alto, Calif. : Annual Reviews, Inc; 1991. Annual review of phytopathology v. 29: p. 247-278; 1991. Literature review. Includes references. Language: English Descriptors: Pseudomonas syringae; Pathotypes; Virulence; Genetic variation; Phytotoxins; Biosynthesis; Biochemical pathways; Phaseolotoxin; Genetic analysis; Genes; Cloning; Molecular biology; Mutants; Plasmids; Strain differences; Gene expression; Literature reviews; Host parasite relationships 171 NAL Call. No.: QR245.F8 Molecular approaches to the analysis of pathogenicity genes from fungi causing plant disease. Garber, R.C. New York : Plenum Press; 1991. The Fungal spore and disease initiation in plants and animals / edited by Garry T. Cole and Harvey C. Hoch. p. 483-502; 1991. Includes references. Language: English Descriptors: Plant pathogenic fungi; Pathogenicity; Genes; Enzymes; Cloning; Mutants; Gene transfer; Isolation techniques; Molecular biology 172 NAL Call. No.: QK710.P62 Molecular basis for novel root phenotypes induced by Agrobacterium rhizogenes A4 on cucumber. Amselem, J.; Tepfer, M. Dordrecht : Kluwer Academic Publishers; 1992 Jun. Plant molecular biology : an international journal on molecular biology, biochemistry and genetic engineering v. 19 (3): p. 421-432; 1992 Jun. Includes references. Language: English Descriptors: Cucumis sativus; Agrobacterium rhizogenes; Genetic transformation; Stems; Explants; Roots; Phenotypes; Plant morphology; Tissue culture; Dna; Plasmids; Restriction mapping; Genes; Gene expression; Messenger RNA; Molecular mapping Abstract: We have used the wild-type Agrobacterium rhizogenes strain A4 to induce roots on cucumber stem explants. Cultures of transformed roots obtained that were capable of hormone- autonomous growth could be grouped in three phenotypic classes. Of particular interest were extremely thick roots of a type not previously described. Characterization of the transferred DNA and of the expression of the corresponding genes allowed us to determine that the genes rolABC of the TL region of the Ri plasmid are sufficient to induce thin roots similar to those observed in other species, while the aux genes of the TR region are sufficient to induce thick roots. Among clones bearing the aux genes, there was a correlation between level of expression of aux2 and root phenotype. 173 NAL Call. No.: TA166.T72 Molecular biology of Erwinia: from soft-rot to antileukaemics. Robert-Baudouy, J. New York, N.Y. : Elsevier Science Publishing Co; 1991 Sep. Trends in biotechnology v. 9 (9): p. 325-329; 1991 Sep. Includes references. Language: English Descriptors: Erwinia; Molecular biology; Biotechnology; Cloning; Escherichia coli; Industrial microbiology; Enzyme preparations; Food processing; Fruit juices; Ascorbic acid Abstract: Soft-rot Erwinia has served to model the regulatory mechanisms in plant-pathogen interactions, and studies have revealed the extracellular pectinolytic, cellulolytic and proteolytic enzymes to be major virulence factors in Erwinia pathogenesis. Apart from its agricultural significance, Erwinia is of increasing interest as an industrial microbe: the Erwinia secretory apparatus, when cloned in Escherichia coli, enables this organism to secrete heterologous Erwinia pectinases, and molecular studies in Erwinia have facilitated the industrial production of pectin methylesterase (important in fruit-juice processing), vitamin C and the antileukaemic asparaginase. 174 NAL Call. No.: QK600.B72 Molecular biology of fungal plant pathogenicity. Oliver, R.P.; Farman, M.L.; Talbot, N.J.; McHale, M.T. Cambridge : Cambridge University Press; 1991. Symposium series - British Mycological Society (18): p. 170-182; 1991. In the series analytic: Applied molecular genetics of fungi / edited by J. F. Peberdy, C. E. Caten, J. E. Ogden and J. W. Bennett. Symposium of the British Mycological Society held at the University of Nottingham, April 1990. Literature review. Includes references. Language: English Descriptors: Plant pathogenic fungi; Genes; Pathogenicity; Virulence; Races; Fungal diseases; Genetic transformation; Reporter genes; Transposable elements; Insertional mutagenesis; Karyotypes; Literature reviews 175 NAL Call. No.: 448.3 J82 Molecular characterization and expression analysis of the anthranilate synthase gene of Pseudomonas syringae subsp. savastanoi. Da Costa E Silva, O.; Kosuge, T. Washington, D.C. : American Society for Microbiology; 1991 Jan. Journal of bacteriology v. 173 (2): p. 463-471; 1991 Jan. Includes references. Language: English Descriptors: Pseudomonas syringae; Ligases; Gene expression; Amino acid sequences; Nucleotide sequences; Genetic regulation; Tryptophan Abstract: The trpE gene, which encodes the large component of the enzyme anthranilate synthase, was isolated from a Pseudomonas syringae subsp. savastanoi (P. savastanoi) cosmid library. Cosmids that complemented an Escherichia coli trpE mutation contained a gene whose product is 86% homologous at the deduced amino acid level to TrpE of Pseudomonas aeruginosa and Pseudomonas putida. Amino acid sequence comparison with other TrpE sequences revealed the existence of conserved regions between the procaryotic and eucaryotic polypeptide sequences analyzed, regions that might be of functional importance. We also report on studies on the expression pattern of this gene. We analyzed the promoter activity of a trpE::lacZ transcriptional fusion, the relative amount of trpE steady-state mRNA, and the activity of anthranilate synthase from cells grown in minimal medium with or without exogenously added tryptophan and in complete medium. We concluded that under the conditions tested, expression of the trpe gene of P. savastanoi is independent of the concentration of tryptophan in the culture medium. Implications of such an expression pattern on the virulence of this bacterium are discussed. 176 NAL Call. No.: 442.8 B5236 Molecular cloning and nucleotide sequence of a pectin lyase gene from Pseudomonas marginalis N6301. Nikaidou, N.; Kamio, Y.; Izaki, K. Orlando, Fla. : Academic Press; 1992 Jan15. Biochemical and biophysical research communications v. 182 (1): p. 14-19; 1992 Jan15. Includes references. Language: English Descriptors: Pseudomonas marginalis; Pectins; Lyases; Genes; Clones; Gene expression; Nucleotide sequences; Amino acid sequences; Escherichia coli; Erwinia carotovora Abstract: A pectin lyase (PNL;EC4.2.2.10) gene of Pseudomonas marginalis N6301 was cloned and expressed in Escherichia coli. We purified PNL from P. marginalis N6301 and determined N- terminal 33 amino acids sequence. From this sequence, we synthesized two oligonucleotide probes. From the analysis of Southern hybridization, 2.1kb EcoRI-SmaI fragment from the chromosomal DNA of P. marginalis was found to hybridize with oligonucleotide probes. Then, we cloned the fragment into pUC119 vector and transformed into E.coli DH5 alpha. A plasmid thus obtained was designated as pPNL6301. E. coli DH5 alpha harboring pPNL6301 expressed PNL activity. The nucleotide sequence of pnl gene in the plasmid pPNL6301 encoding PNL from P. marginalis N6301 was determined. The structural gene of pnl consisted of 936 base pairs. An open reading frame that encodes a 34, 103 dalton polypeptide composed of 312 amino acids was assigned. The molecular weight of the polypeptide predicted from the amino acid composition was close to that of PNL. of P. marginalis N6301 determined. The nucleotide sequence of the LexA binding 5'-flanking region of pnl gene showed the presence of the consensus sequence of LexA site, Pribnow box and ribosome binding site as found in Escherichia coli. The amino acid sequence homology of PNLs and nucleotide sequence homology of pnl gene between P. marginalis N6301 and E. carotovora Er were 60.8% and 57.2%, respectively. 177 NAL Call. No.: SB732.6.M65 Molecular cloning of an aepA gene that activates production of extracelular pectolytic, cellulolytic, and proteolytic enzymes in Erwinia carotovora subsp. carotovora. Murata, H.; McEvoy, J.L.; Chatterjee, A.; Collmer, A.; Chatterjee, A.K. St. Paul, Minn. : APS Press; 1991 May. Molecular plant-microbe interactions : MPMI v. 4 (3): p. 239-246; 1991 May. Includes references. Language: English Descriptors: Erwinia carotovora subsp. carotovora; Enzyme activity; Pectate lyase; Polygalacturonase; Cellulase; Proteinases; Mutants; Strains; Biosynthesis; Genes; Cosmids; Characterization; Molecular genetics; Cloning 178 NAL Call. No.: 448.3 AP5 Molecular cloning of genes related to aflatoxin biosynthesis by differential screening. Feng, G.H.; Chu, F.S.; Leonard, T.J. Washington, D.C. : American Society for Microbiology; 1992 Feb01. Applied and environmental microbiology v. 58 (2): p. 455-460; 1992 Feb01. Includes references. Language: English Descriptors: Aspergillus parasiticus; Aflatoxins; Biosynthesis; Genes; Cloning Abstract: A differential hybridization strategy was used to clone genes associated with aflatoxin biosynthesis. A genomic library, formed between nuclear DNA and the PUC19 plasmid, was screened with three different cDNA probes by the colony hybridization procedure. Nineteen clones were selected; all were positively correlated with and presumably enriched with genes associated with aflatoxin production. Some of these clones were further characterized by using them as probes in Northern (RNA blot) hybridizations. Five clones hybridized strongly with some polyadenylated RNAs formed during the transition to or during idiophase when aflatoxin was produced. However, little or no corresponding hybridization occurred with polyadenylated RNAs formed in early and mid-log growth phase. Two of the clones were further used as probes to hybridize with polyadenylated RNAs formed under aflatoxin- permissive and nonpermissive temperatures. Hybridization occurred with RNA species formed under the permissive temperature only. 179 NAL Call. No.: 442.8 Z34 Molecular cloning of ompRS, a regulatory locus controlling production of outer membrane proteins in Erwinia carotovora subsp. carotovora. Karlsson, M.B.; Pirhonen, M.; Saarilahti, H.T.; Palva, E.T. Berlin, W. Ger. : Springer International; 1991 May. M G G : Molecular and general genetics v. 226 (3): p. 353-360; 1991 May. Includes references. Language: English Descriptors: Erwinia carotovora subsp. carotovora; Escherichia coli; Loci; Cloning; Protein synthesis; Bacterial proteins; Membranes; Dna hybridization; Complementation; Mutants; Restriction mapping; Gene expression; Genetic regulation; Osmoregulation; Virulence; Nicotiana tabacum; Solanum tuberosum Abstract: A locus, ompRS, controlling synthesis of outer membrane proteins was cloned from Erwinia carotovora subsp. carotovora (Ecc) by complementation of an Escherichia coli ompR-envZ mutant. The Ecc ompRS locus was both structurally and functionally similar to the ompR-envZ operon controlling porin gene expression in E. coli as shown by DNA hybridization and complementation of E. coli ompR and envZ mutants. Furthermore, introduction of ompRS into E. coli delta (ompR- envZ) strains restored the osmoregulation of the major outer membrane protein genes ompC and ompF. Maxicell analysis of ompRS-carrying plasmids suggested that proteins similar in size to the E. coli ompR and envZ gene products were encoded by the Ecc ompR and ompS genes, respectively. Introduction of an ompRS transposon mutant onto the Ecc chromosome by marker exchange mutagenesis showed that ompRS is essential for production of a major outer membrane porin in Ecc. This mutational defect could be complemented by clones carrying Ecc ompRS or E. coli ompR envZ. The lack of the porin did not, however, compromise the virulence of these Ecc mutants. 180 NAL Call. No.: 464.8 AN72 Molecular genetic analysis of the rice blast fungus, Magnaporthe grisea. Valent, B.; Chumley, F.G. Palo Alto, Calif. : Annual Reviews, Inc; 1991. Annual review of phytopathology v. 29: p. 443-467; 1991. Literature review. Includes references. Language: English Descriptors: Oryza sativa; Magnaporthe grisea; Pathogenicity; Genes; Genetic analysis; Host specificity; Molecular genetics; Mutants; Genetic transformation; Nucleotide sequences; Molecular mapping; Pathogenesis; Genetic variation; Literature reviews 181 NAL Call. No.: 448.3 J823 Molecular genetics of Pseudomonas syringae pathovar pisi: plasmid involvement in cultivar-specific incompatibility. Bavage, A.D.; Vivian, A.; Atherton, G.T.; Taylor, J.D.; Malik, A.N. Reading : Society for General Microbiology; 1991 Sep. The Journal of general microbiology v. 137 (pt.9): p. 2231-2239; 1991 Sep. Includes references. Language: English Descriptors: Pisum sativum; Cultivars; Pseudomonas syringae pv. pisi; Mutants; Clones; Genes; Cosmids; Plasmids; Dna; Virulence; Varietal resistance; Genetic resistance; Phenotypes; Molecular genetics Abstract: A mutant (PF24) of the race 1 strain, 299A, of Pseudomonas syringae pv.pisi has been characterized in terms of its interactions with pea (Pisum sativum) cultivars. The mutant showed a changed reaction (avirulence to virulence) with a group of pea cultivars, including cvs. Belinda and Puget, previously thought to contain resistance genes R1 and R3. Avirulence towards cv. Puget was restored by transfer of any one of five cosmid clones from a race 3 (strain 870A) gene library to a rifampicin-resistant derivative of PF24. These observations were in agreement with a revised race-specific resistance genotype for Belinda and similar cultivars comprising a single resistance gene, R3. An incompatible interaction was observed between strain PF24 and cvs. Vinco (postulated to harbour race-specific resistance genes R1, R2, R3 and R5) and Hurst's Greenshaft (R4 and possibly R1), indicating that the mutant retains at least one avirulence gene (A1 or A1 and A4). Mutant PF24 showed loss of a cryptic plasmid (pAV212) compared with its progenitor, strain 299A. A subclone (pAV233) of one of the race 3 restoration clones showed strong hybridization with similar-sized digestion fragments in race 3 plasmid DNA, confirming the A3 gene to be plasmid-borne. Strong cross-hybridization was also observed with a single 3.27 kb EcoR1 fragment of plasmid DNA present in strain 299A but absent from strain PF24. This is consistent with the corresponding A3 determinant being located on pAV212 in the race I strain 299A. The novel avirulence gene corresponding to A3 in strain 870A is provisionally designated avrPpi3. A spontaneous race-change variant (strain 1759, which expressed no avirulence phenotype toward the pea differential cultivars) was derived from the race 3 strain 870A. This race 6 strain and a wild isolate of a race 6 strain both lacked plasmid DNA sequences corresponding to the insert in pAV233. 182 NAL Call. No.: QL391.N4J62 Molecular transfer of nematode resistance genes. Williamson, V.M.; Ho, J.Y.; Ma, H.M. Lake Alfred, Fla. : Society of Nematologists; 1992 Jun. Journal of nematology v. 24 (2): p. 234-241; 1992 Jun. Includes references. Language: English Descriptors: Lycopersicon esculentum; Meloidogyne; Pest resistance; Transgenics; Agrobacterium tumefaciens; Dna; Genes; Cloning Abstract: Recombinant DNA techniques have been used to introduce agronomically valuable traits, including resistance to viruses, herbicides, and insects, into crop plants. Introduction of these genes into plants frequently involves Agrobacterium-mediated gene transfer. The potential exists for applying this technology to nematode control by introducing genes conferring resistance to nematodes. Transferred genes could include those encoding products detrimental to nematode development or reproduction as well as cloned host resistance genes. Host genes that confer resistance to cyst or root-knot nematode species have been identified in many plants. The best characterized is Mi, a gene that confers resistance to root- knot nematodes in tomato. A map-based cloning approach is being used to isolate the gene. For development of a detailed map of the region of the genome surrounding Mi, DNA markers genetically linked to Mi have been identified and analyzed in tomato lines that have undergone a recombination event near Mi. The molecular map will be used to identify DNA corresponding to Mi. We estimate that a clone of Mi will be obtained in 2-5 years. An exciting prospect is that introduction of this gene will confer resistance in plant species without currently available sources of resistance. 183 NAL Call. No.: QH442.A1G4 Mutagenesis of a tryptophan codon from TGG to TGA in the cat gene does not prevent its expression in the helical mollicute Spiroplasma citri. Stamburski, C.; Renaudin, J.; Bove, J.M. Amsterdam : Elsevier Science Publishers; 1992. Gene v. 110 (1): p. 133-134; 1992. Includes references. Language: English Descriptors: Spiroplasma citri; Genetic transformation; Reporter genes; Chloramphenicol acetyltransferase; Genetic code; Tryptophan; Mutagenesis; Gene expression; Escherichia coli; Induced mutations Abstract: When the first TGG tryptophan codon of the chloramphenicol acetyltransferase encoding gene, cat, is mutated to the opal stop codon TGA, very little or no activity can be detected in Escherichia coli; in contrast, in the helical mollicute, Spiroplasma citri, the mutated and non- mutated cat genes are expressed equally well. 184 NAL Call. No.: 500 N21P Mutants of Agrobacterium tumefaciens with elevated vir gene expression. Pazour, G.J.; Ta, C.N.; Das, A. Washington, D.C. : The Academy; 1991 Aug15. Proceedings of the National Academy of Sciences of the United States of America v. 88 (16): p. 6941-6945; 1991 Aug15. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Crown gall; Gene expression; Genotypes; Molecular genetics; Mutagenesis; Mutants; Plasmids; Strains Abstract: Expression of Agrobacterium tumefaciens virulence (vir) genes requires virA, virG, and a plant-derived inducing compound such as acetosyringone. To identify the critical functional domains of virA and virG, a mutational approach was used. Agrobacterium A136 harboring plasmid pGP159, which contains virA, virG, and a reporter virB:lacZ gene fusion, was mutagenized with UV light or nitrosoguanidine. Survivors that formed blue colonies on a plate containing 5-bromo-4-chloro-3- indolyl beta-D-galactoside were isolated and analyzed. Quantification of beta-galactosidase activity in liquid assays identified nine mutant strains. By plasmid reconstruction and other procedures, all mutations mapped to the virA locus. These mutations caused an 11- to 560-fold increase in the vegetative level of virB:lacZ reporter gene expression. DNA sequence analysis showed that the mutations are located in four regions of VirA: transmembrane domain one, the active site, a glycine-rich region with homology to ATP-binding sites, and a region at the C terminus that has homology to the N terminus of VirG. 185 NAL Call. No.: SB732.6.M65 Mutants of the Agrobacterium tumefaciens virA gene exhibiting acetosyringone-independent expression of the vir regulon. Ankenbauer, R.G.; Best, E.A.; Palanca, C.A.; Nester, E.W. St. Paul, Minn. : APS Press; 1991 Jul. Molecular plant-microbe interactions : MPMI v. 4 (4): p. 400-406; 1991 Jul. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Mutants; Induced mutations; Genes; Virulence; Genetic regulation; Phenolic compounds; Transcription; Gene expression; Phenotypes; Plasmids; Gene mapping; Nucleotide sequences; Amino acid sequences; Molecular genetics 186 NAL Call. No.: 448.3 J82 Mutation of the miaA gene of Agrobacterium tumefaciens results in reduced vir gene expression. Gray, J.; Wang, J.; Gelvin, S.B. Washington, D.C. : American Society for Microbiology; 1992 Feb. Journal of bacteriology v. 174 (4): p. 1086-1098; 1992 Feb. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Genes; Mutations; Virulence; Gene expression; Nucleotide sequences; Amino acid sequences Abstract: vir regulon expression in Agrobacterium tumefaciens involves both chromosome- and Ti-plasmid-encoded gene products. We have isolated and characterized a new chromosomal gene that when mutated results in a 2- to 10-fold reduction in the induced expression of vir genes by acetosyringone. This reduced expression occurs in AB minimal medium (pH 5.5) containing either sucrose or glucose and containing phosphate at high or low concentrations. The locus was cloned and used to complement A. tumefaciens strains harboring Tn5 insertions in the gene. Sequence analysis of this locus revealed an open reading frame with strong homology to the miaA locus of Escherichia coli and the mod5 locus of Saccharomyces cerevisiae. These genes encode tRNA: isopentenyltransferase enzymes responsible for the specific modification of the A-37 residue in UNN codon tRNA species. The function of the homologous gene in A. tumefaciens was proven by genetic complementation of E. coli miaA mutant strains. tRNA undermodification in A. tumefaciens miaA mutant strains may reduce vir gene expression by causing a reduced translation efficiency. A slight reduction in the virulence of these mutant Agrobacterium strains on red potato plants, but not on tobacco, tomato, kalanchoe, or sunflower plants, was observed. 187 NAL Call. No.: 448.3 J82 Mutational analysis of Agrobacterium tumefaciens virD2: tyrosine 29 is essential for endonuclease activity. Vogel, A.M.; Das, A. Washington, D.C. : American Society for Microbiology; 1992 Jan. Journal of bacteriology v. 174 (1): p. 303-308; 1992 Jan. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Polypeptides; Tyrosine; Phenylalanine; Nucleases; Enzyme activity Abstract: Agrobacterium tumefaciens VirD2 polypeptide, in the presence of VirD1, catalyzes a site- and strand-specific nicking reaction at the T-DNA border sequences. VirD2 is found tightly attached to the 5' end of the nicked DNA. The protein- DNA complex is presumably formed via a tyrosine residue of VirD2 (F. Durrenberger, A. Crameri, B. Hohn, and Z. Koukolikova-Nicola, Proc. Natl. Acad. Sci. USA 86:9154-9158, 1989). A mutational approach was used to study whether a tyrosine residue(s) of VirD2 is required for its activity. By site-specific mutagenesis, a tyrosine (Y) residue at position 29, 68, 99, 119, 121, 160, or 195 of the octopine Ti plasmid pTiA6 VirD2 was altered to phenylalanine (F). The Y-29-F or Y-121-F mutation completely abolished nicking activity of VirD2 in vivo in Escherichia coli. Two other substitutions, Y-68-F and Y-160-F, drastically reduced VirD2 activity. A substitution at position 99, 119, or 195 had no effect on VirD2 activity. Additional mutagenesis experiments showed that at position 29, no other amino acid could substitute for tyrosine without destroying VirD2 activity. At position 121, only a tryptophan (W) residue could be substituted. This, however, yielded a mutant protein with significantly reduced VirD2 activity. The nicked DNA from strains bearing a Y-68-F, Y-99-F, Y-119-F, Y-160-F, Y-195-F, or Y-121-W mutation in VirD2 was always found to contain a tightly linked protein. 188 NAL Call. No.: 464.8 P56 Mycelial incompatibility and molecular markers identify genetic variability in field populations of Sclerotinia sclerotiorum. Kohn, L.M.; Stasovski, E.; Carbone, I.; Royer, J.; Anderson, J.B. St. Paul, Minn. : American Phytopathological Society; 1991 Apr. Phytopathology v. 81 (4): p. 480-485. ill; 1991 Apr. Includes references. Language: English Descriptors: Brassica napus; Sclerotinia sclerotiorum; Strains; Mycelium; Compatibility; Incompatibility; Molecular genetics; Heterogeneity; Genetic markers; Dna; Dna fingerprinting; Characterization; Phenotypes; Genetic polymorphism Abstract: Sixty-three sclerotial strains of Sclerotinia sclerotiorum were obtained from transects in two fields of canola (Brassica napus) in Ontario. Mycelial pairings of the strains in all combinations on agar medium produced either an incompatible reaction in which a reaction line between the two strains developed in the interaction zone, or a compatible reaction in which no reaction line developed. The reaction line was a distinct discontinuity between the two strains, visible as a red line on the colony reverse in pairings made on medium amended with red food coloring. Among the 33 strains from the first field, six mycelial compatibility groups (MCGs) were recognized, the largest group including 19 strains. Among the 30 strains from the second field, many more MCGs were defined. In pairings of 10 monosporous strains from each of six apothecia collected along the transects, all sibling monosporous strains were compatible and no segregation for mycelial compatibility was observed among siblings. Analysis with three molecular markers indicated that each of the MCGs was genetically uniform. With one of these markers, each MCG was uniquely fingerprinted. This fingerprint was produced by a random fragment of nuclear DNA (approximately 4.5 kb) from S. sclerotiorum, pLK44.20, which when used as a cloned probe in Southern hybridizations of DNAs restricted with BamHI detected polymorphisms that corresponded exactly with strain groupings defined by mycelial compatibility. Southern hybridization of high molecular weight DNAs separated by pulsed-field electrophoresis showed that the repetitive element is located on at least five to six chromosomes. Another probe, plasmid pGP637, carrying the mitochondrial 24S rRNA gene from Neurospora crassa, in HindIII-digested DNA, produced six phenotypes. With the exception of phenotypic heterogeneity within one MCG, which had three phenotypes, only one phenotype was observed in strains from each MCG; each of four of the six phenotypes was share 189 NAL Call. No.: 464.8 P56 The national biological impact assessment program. MacKenzie, D.R.; Washington, DC St. Paul, Minn. : American Phytopathological Society; 1991 Mar. Phytopathology v. 81 (3): p. 361; 1991 Mar. Presented at the "Symposium on Assessing the Socioeconomic, Ecological,and Scientific Effects of Agricultural Biotechnology," November 16, 1988, San Diego, California. Language: English Descriptors: Agriculture; Biotechnology; Genetic engineering; Introduced species; Environmental impact; Environmental impact reporting; Usda; Data banks; Field experimentation; Safety; Research projects 190 NAL Call. No.: SB732.6.M65 New pathogenicity loci in Erwinia stewartii identified by random Tn5 mutagenesis and molecular cloning. Coplin, D.L.; Frederick, R.D.; Majerczak, D.R. St. Paul, Minn. : APS Press; 1992 May. Molecular plant-microbe interactions : MPMI v. 5 (3): p. 266-268; 1992 May. Includes references. Language: English Descriptors: Zea mays; Erwinia stewartii; Virulence; Genes; Gene transfer; Genetic transformation; Plasmids; Pseudomonas aeruginosa; Mutants; Characterization; Loci; Gene mapping; Transposable elements; Mutagenesis; Induced mutations 191 NAL Call. No.: 470 SCI2 Nuclear localization of Agrobacterium VirE2 protein in plant cells. Citovsky, V.; Zupan, J.; Warnick, D.; Zambryski, P. Washington, D.C. : American Association for the Advancement of Science; 1992 Jun26. Science v. 256 (5065): p. 1802-1805; 1992 Jun26. Includes references. Language: English Descriptors: Nicotiana tabacum; Agrobacterium; Dna; Transgenics; Proteins Abstract: The Agrobacterium single-stranded DNA (ssDNA) intermediate T-strand is likely transferred to the plant cell nucleus as a complex with a single VirD2 molecule at its 5' end and multiple VirE2 molecules along its length. VirD2 contains a nuclear localization signal (NLS); however, because the T-strand is principally coated with VirE2 molecules, VirE2 also might assist in nuclear uptake. Indeed, VirE2 fused to a reporter protein localizes to plant cell nuclei, a process mediated by two amino acid sequences with homology to the bipartite NLS of Xenopus nucleoplasmin. Moreover, tumorigenicity of an avirulent virE2 mutant is restored when inoculated on transgenic plants expressing VirE2, supporting in planta function of VirE2. 192 NAL Call. No.: 448.3 J82 Nucleotide sequence and molecular characterization of pnlA, the structural gene for damage-inducible pectin lyase of Erwinia carotovora subsp. carotovora 71. Chatterjee, A.; McEvoy, J.L.; Chambost, J.P.; Blasco, F.; Chatterjee, A.K. Washington, D.C. : American Society for Microbiology; 1991 Mar. Journal of bacteriology v. 173 (5): p. 1765-1769. ill; 1991 Mar. Includes references. Language: English Descriptors: Erwinia carotovora subsp. carotovora; Strains; Amino acid sequences; Molecular conformation; Nucleotide sequences; Pectate lyase; Plasmids; Restriction mapping; Transcription; Translation Abstract: In a previous study, pnlA (the DNA damage-inducible structural gene for pectin lyase) of Erwinia carotovora subsp. carotovora 71 was localized to a 1.4-kb DNA segment within a 3.4-kb EcoRI fragment (J. L. McEvoy, H. Murata, and A. K. Chatterjee, J. Bacteriol. 172:3284-3289, 1990). We present here DNA sequence data for a 2.2-kb region revealing an open reading frame of 870 bases, corresponding to a protein (Pnl) of an approximate molecular mass of 32,100 Da and an isoelectric point of 9.92. Although initiation of translation is presumed to occur at the ATG codon, direct protein sequencing revealed alanine as the N-terminal amino acid, probably as a consequence of posttranslational removal of the initiating amino acid. The sequence of the first 20 amino acid residues of Pnl, purified from E. carotovora subsp. carotovora 71, agreed completely with the predicted amino acid sequence of the N-terminal segment. This finding also indicated that Pnl is not subject to processing by a signal peptidase. The transcriptional start site of pnlA was determined to reside 80 bp upstream of the translational start site. Deletion analysis revealed that 218 bp of DNA upstream of the transcriptional start site is sufficient for induction of pnlA by mitomycin C. Within 600 bp upstream of the translational start site, no sequences resembling a LexA binding site (SOS box) or a cyclic AMP receptor protein binding site were found. However, palindromic sequences were detected at -187 and -86 bp relative to the translational start site, and these could be potential sites for the binding of a regulatory protein(s). Comparison of the deduced amino acid sequence for PnlA with that of a Pnl from Aspergillus niger and with those of various pectate lyases of Erwinia species revealed a low degree of homology dispersed throughout the length of the proteins. 193 NAL Call. No.: 500 N21P Opine catabolism and conjugal transfer of the nopaline Ti plasmid pTiC58 are coordinately regulated by a single repressor. Beck von Bodman, S.; Hayman, G.T.; Farrand, S.K. Washington, D.C. : The Academy; 1992 Jan15. Proceedings of the National Academy of Sciences of the United States of America v. 89 (2): p. 643-647. ill; 1992 Jan15. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Amino acid sequences; Regulation; Mutants; Nopaline; Nucleotide sequences; Plasmids; Strains; Transcription Abstract: The Ti plasmids of Agrobacterium tumefaciens are conjugal elements whose transfer is strongly repressed. Transfer is induced by the conjugal opines, a group of unique carbon compounds synthesized in crown gall tumors. The opines also induce Ti plasmid-encoded genes required by the bacteria for opine catabolism. We have cloned and sequenced a gene from the Ti plasmid pTiC58, whose product mediates the opine- dependent regulation of conjugal transfer and catabolism of the conjugal opines, agrocinopines A and B. The gene, accR, is closely linked to the agrocinopine catabolic locus. A spontaneous mutant Ti plasmid, pTiC58Tra(c), which constitutively expresses conjugal transfer and opine catabolism, was complemented in trans by a clone of wild-type accR. Comparative sequence analysis identified a 5-base-pair deletion close to the 5' end of the mutant accR allele from pTiC58Tra(c). Analysis of lacZ fusions in conjugal transfer and opine catabolic structural genes demonstrated that the accR-encoded function is a transcriptional repressor. accR can encode a 28-kDa protein. This protein is related to a class of repressor proteins that includes LacR, GutR, DeoR, FucR, and GlpR that regulate sugar catabolic systems in several bacterial genera. 194 NAL Call. No.: 448.3 J82 Opine transport genes in the octopine (occ) and nopaline (noc) catabolic regions in Ti plasmids of Agrobacterium tumefaciens. Zanker, H.; Lintig, J. von; Schroder, J. Washington, D.C. : American Society for Microbiology; 1992 Feb. Journal of bacteriology v. 174 (3): p. 841-849; 1992 Feb. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Genes; Octopine; Nopaline; Plasmids; Catabolism; Nucleotide sequences; Amino acid sequences Abstract: The occ and noc regions of octopine and nopaline Ti plasmids in Agrobacterium tumefaciens are responsible for the catabolic utilization of octopine and nopaline, respectively. Opine-inducible promoters, genes for regulatory proteins and for catabolic enzymes, had been identified in previous work. However, both regions contained additional DNA stretches which were under the control of opine-inducible promoters, but the functions were unknown. We investigated these stretches by DNA sequence and functional analyses. The sequences showed that both of the catabolic regions contain a set of four genes which are transcribed in the same direction. The occ and noc region genes are related, but the arrangement of the genes is different. The deduced polypeptides are related to those of binding protein-dependent transport systems of basic amino acids in other bacteria. The comparison suggested that three of the polypeptides are located in the membrane and that one is a periplasmic protein. We constructed cassettes which contained either the putative transport genes only or the complete occ or noc region; all constructs, however, included the elements necessary for opine-induced expression of the genes (the regulatory gene and the inducible promoters). Uptake studies with 3H-labelled octopine showed that the putative transport genes in the occ region code for octopine uptake proteins. The corresponding studies with 3H-labelled nopaline and the noc region cassettes indicated that the uptake of nopaline requires the putative transport genes and additional functions from the left part of the noc region. 195 NAL Call. No.: 448.3 J82 Organization and environmental regulation of the Pseudomonas syringae pv. syringae 61 hrp cluster. Xiao, Y.; Lu, Y.; Heu, S.; Hutcheson, S.W. Washington, D.C. : American Society for Microbiology; 1992 Mar. Journal of bacteriology v. 174 (6): p. 1734-1741; 1992 Mar. Includes references. Language: English Descriptors: Pseudomonas syringae pv. syringae; Genes; Gene expression; Genetic regulation; Infection; Amino acids; Pathogenicity; Host specificity Abstract: The ability of Pseudomonas syringae pv. syringae 61 to elicit the hypersensitive response in nonhost plant species has been linked to a cluster of hrp/hrm genes whose expression appears to be environmentally regulated. To understand the genetic organization of this hrp/hrm gene cluster and its expression during the interaction with nonhost plant species better, we constructed a set of chromosomal hrp-uidA fusions in P. syringae pv. syringae 61 by Tn5-gusA1 mutagenesis of the cloned hrp/hrm gene cluster and transferred them into the genome by marker exchange mutagenesis. Complementation analysis employing plasmid-borne Tn5-gusA1 insertions and previously characterized chromosomal TnphoA mutations defined at least eight apparent transcriptional units within the hrp/hrm cluster, several of which were multicistronic. The expression of hrp-uidA fusions in seven of these apparent hrp transcriptional units increased following inoculation into tobacco leaves. Enhanced expression from a representative fusion was detected 1 h after inoculation of tobacco leaves. The induction observed in planta was similar to the levels detected following culture of the bacteria in minimal-salts medium: irrespective of the carbon source. Complex amino acid sources, such as peptone, repressed the expression of P. syringae pv. syringae 61 hrp genes at levels exceeding 0.028%. The results indicate that enhanced expression of hrp genes occurs early in the interaction with nonhost plant species in an apparent response to altered nutritional conditions. 196 NAL Call. No.: QH426.P56 Organization of the agropine synthesis region of the T-DNA of the Ri plasmid from Agrobacterium rhizogenes. Bouchez, D.; Tourneur, J. Orlando, Fla. : Academic Press; 1991 Jan. Plasmid v. 25 (1): p. 27-39; 1991 Jan. Includes references. Language: English Descriptors: Agrobacterium rhizogenes; Plasmids; Dna; Amino acid derivatives; Amino acid metabolism; Nucleotide sequences; Genes; Molecular mapping; Ligases; Amino acid sequences Abstract: The agropine/mannopine synthesis region of the TR region of the Ri plasmid of Agrobacterium rhizogenes strain A4 was localized on the basis of sequence similarity with probes from Ti plasmids of Agrobacterium tumefaciens and analysis of transposon insertions. The nucleotide sequence of the right part of the TR-DNA of pRiA4, encompassing the three genes involved in mannityl-opine synthesis, was determined and compared to the sequence of the corresponding region of the octopine-type Ti plasmid pTi15955. The organization of this region is strongly conserved between Ri and Ti plasmids, but the similarity is restricted to the coding sequences: no homology was detected in the 5'and 3' flanking sequences. The mas1' and ags proteins are the most conserved, showing more than 68% amino acid conservation, whereas the mas2' proteins are only 59% identical. Significant G/C content and codon usage differences are observed between pTi15955 and pRiA4. An open reading frame strongly similar to that of bacterial repressors is situated immediately to the right of the TR region. 197 NAL Call. No.: 448.3 J82 The osa gene of pSa encodes a 21.1-kilodalton protein that suppresses Agrobacterium tumefaciens oncogenicity. Close, S.M.; Kado, C.I. Washington, D.C. : American Society for Microbiology; 1991 Sep. Journal of bacteriology v. 173 (17): p. 5449-5456; 1991 Sep. Includes references. Language: English Descriptors: Datura stramonium; Agrobacterium tumefaciens; Genes; Bacterial proteins; Plasmids; Nucleotide sequences; Amino acid sequences; Gene mapping; Virulence; Inhibition; Tumors; Crown gall; Stems Abstract: The incompatibility group W plasmid pSa suppresses Agrobacterium tumefaciens oncogenicity (J. Loper and C. Kado, J. Bacteriol. 139:591-596, 1979). The oncogenic suppressive activity was localized to a 3.1-kb region of pSa by Tn5 mutagenesis and deletion analysis. Within this fragment, a 1.1-kb subclone bearing oncogenic suppressive activity was subjected to further characterization. Nucleotide sequencing of the 1.1-kb fragment revealed a 570-bp open reading frame (ORF1) that has a coding capacity for a protein of 21.1 kDa. Sequencing of flanking regions revealed a second ORF (ORF2) located 3 bp upstream of ORF1, with a coding capacity for a protein of 22.8 kDa. Gene fusions of these ORFs to a T7(phi)10 expression system in Escherichia coli resulted in the synthesis of polypeptides of the predicted sizes. An E. coli promoter consensus sequence was not found in the expected positions in the region preceding ORF1. However, several sequences with similarity to the consensus -10 sequence of the A. tumefaciens vir gene promoters were found upstream of ORF1. Potential translational start signals are upstream of ORF1 and ORF2. These sequences showed no significant similarity at the nucleotide or amino acid levels with those in available data bases. However, the C-terminal portion of the ORF1 protein is rich in hydrophobic residues. Perhaps oncogenicity suppression is effected by an association of this protein with the Agrobacterium membrane such that T-DNA transfer is blocked. 198 NAL Call. No.: QH426.C8 Parasexual cycle and genetic analysis following protoplast fusion in Nectria haematococca. Daboussi, M.J.; Gerlinger, C. Berlin, W. Ger. : Springer International; 1992. Current genetics v. 21 (4/5): p. 385-392; 1992. Includes references. Language: English Descriptors: Nectria haematococca; Protoplast fusion; Genetic transformation; Parasexuality; Heteroploidy; Heterokaryosis; Haploids; Segregation; Linkage; Mitotic recombination; Recombination; Crossing over Abstract: Protoplasts of multiauxotrophic strains of Nectria haematococca (the perfect form of Fusarium solani) were fused and grown on different selective media. Following protoplast fusion, rapidly growing heterokaryons were formed at high frequency (about 1%). By collecting uninucleate microconidia from these heterokaryons, it was possible to isolate a few colonies with new combinations of the parental markers. On some selective media, non-heterokaryotic fusion products, easily distinguishable from heterokaryons by their growth characteristics, were detected at low frequency. These colonies were either stable haploid recombinants or unstable 'hybrids' of unknown ploidy. Genetic analysis of 'hybrids' in which six factors were heterozygous provided evidence for nuclear fusion events. These 'hybrid' colonies spontaneously segregated a large number of haploid recombinants, allowing the analysis of linkage relationships between markers. The detection of a mitotic linkage between two markers which appeared unlinked following meiosis, demonstrates that mitotic mapping may be an important complement to meiotic analysis for mapping the chromosomes of Nectria haematococca. 199 NAL Call. No.: QK1.B38 The parasexual cycle in Ustilago scabiosae (Ustilaginales). Garber, E.D.; Ruddat, M. Chicago, Ill. : University of Chicago Press; 1992 Mar. International journal of plant sciences v. 153 (1): p. 98-101; 1992 Mar. Includes references. Language: English Descriptors: Ustilago; Ustilago violacea; Parasexuality; Fungal spores; Color; Phenotypes; Diploidy; Recombination; Haploidy; Haploids; Induced mutations; Genetic markers; Mating; Alleles 200 NAL Call. No.: SB327.A1B5 Parental effects on performance of common bacterial blight resistant and susceptible selections of common bean. Maharaj, P.; Michaels, T.E. Fort Collins, Colo : Howard F. Schwartz, Colorado State University; 1992. Annual report of the Bean Improvement Cooperative v. 35: p. 84-85; 1992. Includes references. Language: English Descriptors: Phaseolus vulgaris; Phaseolus acutifolius; Xanthomonas campestris pv. phaseoli; Disease resistance; Plant breeding; Gene transfer; Lines 201 NAL Call. No.: 464.8 P56 A pathogenicity locus from Xanthomonas citri enables strains from several pathovars of X. campestris to elicit cankerlike lesions on citrus. Swarup, S.; De Feyter, R.; Brlansky, R.H.; Gabriel, D.W. St. Paul, Minn. : American Phytopathological Society; 1991 Jul. Phytopathology v. 81 (7): p. 802-809; 1991 Jul. Includes references. Language: English Descriptors: Citrus paradisi; Xanthomonas campestris pv. citri; Pathotypes; Virulence; Genes; Loci; Dna libraries; Screening; Clones; Plasmids; Xanthomonas; Strains; Strain differences; Insertional mutagenesis; Phenotypes; Lesions; Host range Abstract: A virulence enhancement approach was used to clone a pathogenicity (pth) locus from a highly virulent pathogen by assaying the library in a second, less virulent strain that was compatible with the same host. A genomic library of the virulent Asiatic canker pathogen Xanthomonas citri was conjugally transferred to the opportunistic pathogen, X. campestris citrumelo, and the transconjugants were screened on Citrus paradisi 'Duncan' (grapefruit) leaves. Transconjugants able to induce host cell proliferation and raised, Asiatic cankerlike lesions were identified, and clone pSS10.35 was found to carry the gene(s) responsible. This clone was transferred to other Xanthomonas strains, including two that are weakly pathogenic to citrus in greenhouse tests (members of X. c. alfalfae and X. c. cyamopsidis) and two that are avirulent on citrus (X. phaseoli and X. c. malvacearum). Transconjugants of the two weakly pathogenic Xanthomonas strains induced cankerlike lesions when inoculated on citrus; these same strains became avirulent on their homologous host plants. Transconjugants of X. phaseoli and X. c. malvacearum strains remained unaltered in phenotype on citrus. A 3.7-kb region of pSS10.35 carrying the pthA locus was identified by subcloning and Tn5-gusA mutagenesis. Marker-exchange mutagenesis of X. citri using Tn5-gusA insertions in the 3.7- kb region resulted in a complete loss of virulence (disease symptoms and growth in planta) on citrus and loss of the hypersensitive response on heterologous hosts (i.e., an Hrp- phenotype). The Hrp- phenotype, but not growth in planta, of the marker-exchanged mutants was restored by subclones of pSS10.35 containing the 3.7-kb region. 202 NAL Call. No.: SB732.6.M65 A pathogen-induced wheat gene encodes a protein homologous to glutathione-S-transferases. Dudler, R.; Hertig, C.; Rebmann, G.; Bull, J.; Mauch, F. St. Paul, Minn. : APS Press; 1991 Jan. Molecular plant-microbe interactions : MPMI v. 4 (1): p. 14-18; 1991 Jan. Includes references. Language: English Descriptors: Triticum aestivum; Disease resistance; Genetic resistance; Erysiphe graminis; Strains; Strain differences; Pathogenicity; Induced resistance; Genes; Defense mechanisms; Genetic regulation; Glutathione transferase; Nucleotide sequences; Amino acid sequences; Genetic analysis; Exons; Introns 203 NAL Call. No.: QH442.G456 PCR increasingly employed in agricultural and veterinary biotechnology. Fox, S. New York, N.Y. : Mary Ann Liebert; 1992 Jun01. Genetic engineering news v. 12 (9): p. 6, 7, 9; 1992 Jun01. Language: English Descriptors: Polymerase chain reaction; Plant pests; Plant pathogens; Plant diseases; Animal diseases; Diagnosis; Genetic engineering; Plant breeding; Animal breeding; Biotechnology 204 NAL Call. No.: 450 J8224 Phenotypic effects of isolated pRiA4 TL-DNA rol genes in the presence of intact TR-DNA in transgenic plants of Solanum dulcamara L. McInnes, E.; Morgan, A.J.; Mulligan, B.J.; Davey, M.R. Oxford : Oxford University Press; 1991 Oct. Journal of experimental botany v. 42 (243): p. 1279-1286; 1991 Oct. Includes references. Language: English Descriptors: Solanum dulcamara; Agrobacterium rhizogenes; Plant diseases; Genetic transformation; Transgenics; Genes; Plasmids; Roots; Phenotypes; Leaves; Plant morphology; Growth rate; Epinasty; Amino acid derivatives Abstract: The effect of the rol genes, together with the TR- DNA of pRiA4 on the phenotype of Solanum dulcamara plants, was analysed. Plants transformed by Agrobacterium strain BN1010::rolA (rolA+TR+) exhibited severe leaf wrinkling, whereas plants transformed by strain BN1010::rolC (rolC+TR+) had a typical 'hairy root' phenotype. Leaf discs excised from these latter plants produced roots on hormone-free medium. BN1010::rolABC (rolABC+TR+) transformed plants had an exaggerated transformed phenotype. Some of the BN1010::rolABC transformants had positively geotropic root growth which correlated with the presence of multiple copies of the TR-DNA. S. dulcamara plants, transformed by the TR-DNA region only, exhibited epinasty. Scanning electron microscopy of plants containing various regions of agropine Ri T-DNA revealed that transformation causes changes in basic plant structure. 205 NAL Call. No.: QK725.P532 Phenylpropanoid pathway intermediates regulate transient expression of a chalcone synthase gene promoter. Loake, G.J.; Choudhary, A.D.; Harrison, M.J.; Mavandad, M.; Lamb, C.J.; Dixon, R.A. Rockville, Md. : American Society of Plant Physiologists; 1991 Aug. The Plant cell v. 3 (8): p. 829-840; 1991 Aug. Includes references. Language: English Descriptors: Phaseolus vulgaris; Medicago sativa; Colletotrichum lindemuthianum; Promoters; Naringenin-chalcone synthase; Chloramphenicol acetyltransferase; Reporter genes; Chimeras; Gene expression; Transcription; Genetic regulation; Cinnamic acid; P-coumaric acid; Carbohydrates; Cell wall components; Hyphae; Deletions; Genetic transformation; Protoplasts; Electroporation Abstract: A chimeric gene construct containing a bean chalcone synthase (CHS) promoter fused to the chloramphenicol acetyltransferase (CAT) reporter gene was strongly expressed when electroporated into alfalfa protoplasts that were then exposed to a fungal elicitor. Low concentrations (5 X 10(-6) to 10(-4) M) of exogenously applied transcinnamic acid (CA), the first intermediate of the phenylpropanoid pathway, slightly stimulated elicitor-induced CAT expression, whereas high concentrations (>1O(-4) M) severely reduced expression to below the levels observed in the absence of elicitor. In contrast, trans-p-coumaric acid (4-CA, the second intermediate in the pathway) stimulated expression from the CHS promoter up to 4.5-fold at 5 X 10(-4) M. Expression of CAT driven by the promoters of other elicitor-inducible defense response genes was not markedly affected by CA or 4-CA. Stimulation of CHS promoter expression by low concentrations of CA and 4-CA was completely abolished by 5' deletion to position -130, but not -174. When the -180 to -130 region of the CHS15 promoter was coelectroporated into elicited protoplasts on a separate plasmid along with the intact -326 CHS-CAT construct, the decreased CAT expression as a function of CA or 4-CA concentration was consistent with the coelectroporated sequence competing in trans with the intact promoter for the binding of a factor(s) involved in the up regulation of CHS transcription by 4-CA and low concentrations of CA. Our data support the hypothesis that phenylpropanoid compounds may act as natural and specific regulators of plant gene expression and define the location of a cis-acting element in the CHS15 promoter involved in the induction by phenylpropanoid pathway intermediates. 206 NAL Call. No.: 448.3 J82 Phylogenetic analysis and evolution of RNase P RNA in proteobacteria. Brown, J.W.; Haas, E.S.; James, B.D.; Hunt, D.A.; Pace, N.R. Washington, D.C. : American Society for Microbiology; 1991 Jun. Journal of bacteriology v. 173 (12): p. 3855-3863; 1991 Jun. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Alcaligenes; Desulfovibrio desulfuricans; Firmicutes; Gram negative bacteria; Phylogeny; Genes; Rna; Ribonucleases; Nucleotide sequences; Cloning; Molecular conformation Abstract: The secondary structures of the eubacterial RNase P RNAs are being elucidated by a phylogenetic comparative approach. Sequences of genes encoding RNase P RNA from each of the recognized subgroups (alpha, beta, gamma, and delta) of the proteobacteria have now been determined. These sequences allow the refinement, to nearly the base pair level, of the phylogenetic model for RNase P RNA secondary structure. Evolutionary change among the RNase P RNAs was found to occur primarily in four discrete structural domains that are peripheral to a highly conserved core structure. The new sequences were used to examine critically the proposed similarity (C. Guerrier-Takada, N. Lumelsky, and S. Altman, Science 246:1578-1584, 1989) between a portion of RNase P RNA and the "exit site" of the 23S rRNA of Escherichia coli. Phylogenetic comparisons indicate that these sequences are not homologous and that any similarity in the structures is, at best, tenuous. 207 NAL Call. No.: 448.3 J82 Physical and functional characterization of the gene cluster encoding the polyketide phytotoxin coronatine in Pseudomonas syringae pv. glycinea. Young, S.A.; Park, S.K.; Rodgers, C.; Mitchell, R.E.; Bender, C.L. Washington, D.C. : American Society for Microbiology; 1992 Mar. Journal of bacteriology v. 174 (6): p. 1837-1843; 1992 Mar. Includes references. Language: English Descriptors: Pseudomonas syringae pv. glycinea; Phytotoxins; Genes; Plasmids; Biosynthesis; Mutations Abstract: Pseudomonas syringae pv. glycinea PG4180 produces the polyketide phytotoxin coronatine. The coronatine synthesis genes in PG4180 were previously shown to reside on a 90-kb plasmid designated p4180A. In the present study, clones containing a 34-kb region of p4180A were saturated with Tn5, and 71 unique mutations were recombined into p4180A by marker exchange. The effect of each mutation on coronatine synthesis was determined by analyzing the organic acids produced by the mutants by reverse-phase high-performance liquid chromatography. The organic acids of selected mutants were derivatized to their methyl esters and analyzed by gas chromatography and gas chromatography-mass spectrometry. Mutations in a 20.5-kb region of p4180A completely blocked the synthesis of coronafacic acid and coronatine. Mutations within a 4.4-kb region of p4180A prevented the formation of coronatine but allowed for production of coronafacic acid, coronafacoyl-valine, coronafacoylisoleucine, and coronafacoylalloisoleucine. The phenotypes of selected mutants were further confirmed in feeding experiments in which coronafacic acid or coronamic acid was added to the culture media. The results of this study allow us to speculate on the likely sequence of steps in the later stages of coronatine biosynthesis. 208 NAL Call. No.: 450 P692 Physical, chemical, developmental, and genetic factors that modulate the Agrobacterium-Vitis interaction. Lowe, B.A.; Krul, W.R. Rockville, Md. : American Society of Plant Physiologists; 1991 May. Plant physiology v. 96 (1): p. 121-129; 1991 May. Includes references. Language: English Descriptors: Vitis rupestris; Vitis; Agrobacterium tumefaciens; Tumors; Pathogenicity; Genetic regulation; Genetic resistance; Host parasite relationships; Compatibility; Genetic transformation; Light relations; Auxins; Genotypes; Hybrids; Host range; Necrosis; Phenotypes; Cultivars Abstract: Tumor formation in Vitis species and hybrids, incited by Agrobacterium tumefaciens, was altered by chemical, physical, developmental, and genetic variables. Knowledge of the effect of these variables was used to develop a stringent in vitro assay system to select parents for a study of genetic factors that modulate tumor formation. Tumor formation was reduced by short day preconditioning of assay plants and by inoculation of the morphological apex of isolated stem segments. Pretreatment of plants with auxin or cytokinin altered specificity in various combinations of strains and host genotypes. All Vitis species and hybrids formed tumors in response to strains designated as limited host range, but some displayed a necrotic reaction (cell death at and below site of inoculation) or a null response (same as the response to inoculation with an avirulent strain) to strains designated as wide host range (VC Knauf, CG Panagopoulos, EW Nester [1982) Phytopathology 72: 1545-1549). Screens of F1 progeny, derived from crosses of null, necrotic, and tumor-producing phenotypes, demonstrated that the null and the necrotic phenotypes were modulated by dominant and recessive host genes. The extent of cellular necrosis in the necrotic phenotype was modified by the morphological location of the inoculation site, by the presence of buds on the host stem, and by deletion of the tryptophane monooxygenase locus gene of the Ti-plasmid. 209 NAL Call. No.: Q320.B56 Planned introductions in biological control. Ehler, L.E. Stoneham, Mass. : Butterworth Publishers; 1991. Biotechnology (15): p. 21-39; 1991. In the Series Analytic: Assessing Ecological Risks of Biotechnology / edited by Lev R. Ginzburg. Includes references. Language: English Descriptors: Biological control agents; Introduction; Plant protection; Release techniques; Environmental impact; Biotechnology; Transgenics; Ecological balance 210 NAL Call. No.: 442.8 AN72 Plant resistance to fungal diseases induced by the infection of cucumber mosaic virus attenuated by satellite RNA. Qin, B.; Zhang, X.; Wu, G.; Tien, P. Warwick : Association of Applied Biologists; 1992 Feb. Annals of applied biology v. 120 (2): p. 361-366; 1992 Feb. Includes references. Language: English Descriptors: Cucumis sativus; Nicotiana tabacum; Lycopersicon esculentum; Pseudoperonospora cubensis; Fulvia fulva; Alternaria longipes; Fungal diseases; Cucumber mosaic cucumovirus; Rna; Attenuation; Biological control agents; Disease resistance; Transgenics; Infection; Symptoms; Field tests; Tests 211 NAL Call. No.: 464.8 P56 Plasmid DNA fingerprints distinguish pathotypes of Xanthomonas campestris pv. citri, the causal agent of citrus bacterial canker disease. Pruvost, O.; Hartung, J.S.; Civerolo, E.L.; Dubois, C.; Perrier, X. St. Paul, Minn. : American Phytopathological Society; 1992 Apr. Phytopathology v. 82 (4): p. 485-490; 1992 Apr. Includes references. Language: English Descriptors: Citrus; Xanthomonas campestris pv. citri; Pathotypes; Genetic analysis; Dna; Plasmids; Dna fingerprinting; Strains; Identification; Strain differences; Characterization; Genetic variation Abstract: Plasmid DNA was isolated from 54 strains of Xanthomonas campestris pv. citri, associated with different forms of citrus bacterial canker disease (CBCD). The number of plasmids per strain varied from one to five. A total of 24 plasmid bands with sizes from 7 to 100 kilobases (kb) were identified. Strains that had identical plasmid profiles were generally associated with the same form of CBCD. After digesting the plasmid DNA with each of three restriction endonucleases, 87 fragments with different sizes from about 1 to 30 kb were visualized. Strains belonging to a specific CBCD group shared plasmid DNA fragments of similar sizes. Dendrograms derived from plasmid DNA fingerprint analyses allowed us to clearly distinguish A, B, and C pathotypes of X. c. citri. The strain Xc90, associated with bacteriosis of Mexican lime in Mexico (CBCD-D) was not clearly distinguishable from strains associated with cancrosis B (CBCD-B) from Argentina and Uruguay. Plasmid DNA fragments specifically associated with some groups of strains were identified. A BamHI fragment from a CBCD-A strain was used as a hybridization probe. A strong signal was recorded in all CBCD-A strains studied. Weaker hybridization signals were observed with one or two high molecular weight bands in all CBCD-B strains studied. All three type C strains had a band of slightly smaller size than the probe, but which hybridized only very weakly. Strain Xc70 also had a homologous larger band similar in size to one found in the CBCD-B strains. Hierarchical cluster analysis of the RFLP data from the plasmid DNA revealed phenetic clusters strikingly similar to those obtained previously from analysis of genomic DNA, lending support to the concept of balanced co-evolution of plasmid and chromosomal genomes. 212 NAL Call. No.: 464.8 P56 Plasmid, genomic, and bacteriocin diversity in U.S. strains of Xanthomonas campestris pv. oryzae. Xu, G.W.; Gonzalez, C.F. St. Paul, Minn. : American Phytopathological Society; 1991 Jun. Phytopathology v. 81 (6): p. 628-631; 1991 Jun. Includes references. Language: English Descriptors: Oryza sativa; Xanthomonas campestris pv. oryzae; Strains; Strain differences; Characterization; Plasmids; Dna; Genome analysis; Bacteriocins; Diversity; Plant pathogenic bacteria Abstract: Twenty-six strains of Xanthomonas campestris pv. oryzae isolated during a recent outbreak of bacterial leaf blight of rice in the United States were analyzed for their plasmid, genome, and bacteriocin diversity. Twenty of the strains harbored indigenous plasmid(s) and could be divided into three distinct groups. Restriction fragment length polymorphism (RFLP) analyses of genomic DNA revealed hybridization profiles that separated the strains into four groups. Four bacteriocin groups were identified among the strains tested. Five subgroups were identified based on plasmid content, RFLP analyses, and bacteriocin typing. 213 NAL Call. No.: 448.3 J82 Polygalacturonase is a virulence factor in Agrobacterium tumefaciens biovar 3. Rodriguez-Palenzuela, P.; Burr, T.J.; Collmer, A. Washington, D.C. : American Society for Microbiology; 1991 Oct. Journal of bacteriology v. 173 (20): p. 6547-6552; 1991 Oct. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Strains; Polygalacturonase; Genes; Clones; Virulence; Host specificity; Vitis vinifera Abstract: Agrobacterium tumefaciens biovar 3 causes both crown gall and root decay of grapes. All biovar 3 strains, regardless of their tumorigenicity, produce in culture a single polygalacturonase with a pI around 4.5. A. tumefaciens biovar 3 strain CG49 was mutagenized with Tn5 by using pSUP2021 as a suicide vector. A mutant strain, CG50, lacking polygalacturonase activity was isolated. The mutation was due to a single Tn5 insertion in an 8.5-kb EcoRI fragment that also contained the polygalacturonase structural gene. The polygalacturonase-encoding pehA gene was cloned in Escherichia coli by using the plasmid pBluescript as a vector. Activity- stained isoelectric focusing gel analysis demonstrated that E. coli cells harboring the pehA+ recombinant plasmid pCPP2067 produced a polygalacturonase in culture with the same pI as the enzyme produced by CG49. The peha gene was localized within a 2.5-kb HindIII-salI fragment. This fragment was used as a probe in Southern hybridization analysis and showed that no closely related genes are present in A. tumefaciens biovars 1 or 2, Rhizobium leguminosarum, or Bradyrhizobium japonicum. The polygalacturonase mutant was unable to induce root decay in grapes (Vitis vinifera cv. Chardonnay) and was substantially less tumorigenic than the wild type in grape stems when low levels of inoculum were used, although both strains were equally tumorigenic in potato disc assays. The results indicate that polygalacturonase is a virulence factor in both the root decay and crown gall incited in grapes by A. tumefaciens biovar 3. 214 NAL Call. No.: 448.3 AP5 Polygalacturonase production by Agrobacterium tumefaciens biovar 3. McGuire, R.G.; Rodriguez-Palenzuela, P.; Collmer, A.; Burr, T.J. Washington, D.C. : American Society for Microbiology; 1991 Mar. Applied and environmental microbiology v. 57 (3): p. 660-664; 1991 Mar. Includes references. Language: English Descriptors: Vitis; Agrobacterium tumefaciens; Strains; Polygalacturonase; Plasmids; Pathogens Abstract: Agrobacterium tumefaciens biovar 3 causes both crown gall and root decay of grape. Twenty-two Agrobacterium strains representing biovars 1, 2, and 3 were analyzed for tumorigenicity, presence of a Ti plasmid, ability to cause grape seedling root decay, and pectolytic activity. All of the biovar 3 strains, regardless of their tumorigenicity or presence of a Ti plasmid, caused root decay and were pectolytic, whereas none of the biovar 1 and 2 strains had these capacities. Isoelectrically focused gels that were activity stained with differentially buffered polygalacturonate-agarose overlays revealed that all of the biovar 3 strains produced a single polygalacturonase with a pH optimum of 4.5 and pIs ranging from 4.8 to 5.2. The enzyme was largely extracellular and was produced constitutively in basal medium supplemented with a variety of carbon sources including polygalacturonic acid. Lesions on grape seedling roots inoculated with A. tumefaciens biovar 3 strain CG49 yielded polygalacturonase activity with a pI similar to that of the enzyme produced by the bacterium in culture. These observations support the hypothesis that the polygalacturonase produced by A. tumefaciens biovar 3 has a role in grape root decay. 215 NAL Call. No.: QH426.P56 Polymorphism of nopaline-type T-DNAs from Agrobacterium tumefaciens. Wabiko, H.; Kagaya, M.; Sano, H. Orlando, Fla. : Academic Press; 1991 Jan. Plasmid v. 25 (1): p. 3-15; 1991 Jan. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Plasmids; Dna; Restriction mapping; Restriction fragment length polymorphism; Amino acid derivatives; Strain differences; Molecular mapping; Pathogenicity; Tumors; Crown gall; Petunia; Populus; Populus grandidentata Abstract: The structure of several T-DNAs of agrobacterium tumefaciens was determined by molecular cloning and Southern hybridization. The T-DNAs cloned in Escherichia coli vectors from four different nopaline type strains (PyTE1, PO31, PO22, and AKE10) showed various sizes of restriction enzyme fragments. Comparative analysis of the restriction maps revealed that the T-DNAs were composed of three distinct structural domains: (1) the region proximal to the right border (Domain I) containing the portion essential for tumorigenicity, (2) the proximity to the left border (Domain II), and (3) the region between the two domains (Domain III) to both of which no functional assignments have yet been made. The restriction map indicated that the Domains I and II were conserved in the most clones, including the well-characterized T37 T-DNA. The only exception was AKK1 (obtained from AKE10) which differed in Domain I. In the Domain III, insertions of 1.5- or 1.6-kb DNA were found in four clones, whereas an additional 2.5-kb insertion was found in one clone (PO22P1). The individual T-DNAs including Domain III with insertions was demonstrated in petunia and poplar tumors induced by the referred A. tumefaciens strains. However, resulting tumors differed in morphology and growth. These results suggest that the length polymorphism of the nopaline type T-DNA can be accounted by DNA insertions, and that diverse T-DNAs reflect their different roles in tumorigenicity. 216 NAL Call. No.: QH301.A43 Positive regulation of the expression of the virD locus of the nopaline-type Ti-plasmid C58 of Agrobacterium tumefaciens. Li, K.G.; Andrianov, V.M.; Piruzyan, E.S. New York, N.Y. : Consultants Bureau; 1991 Mar. Biology bulletin of the Academy of Sciences of the USSR v. 17 (3): p. 211-214. ill; 1991 Mar. Translated from: Izvestiia Akademii Nauk SSSR, Seriia Biologicheskaia, v. 17 (3), 1990, p. 325-328. (511 SA2B). Includes references. Language: English; Russian Descriptors: Agrobacterium tumefaciens; Crown gall; Gene expression; Gene mapping; Genetic regulation; Loci; Molecular weight; Nopaline; Plasmids; Promoters; Soil bacteria; Escherichia coli 217 NAL Call. No.: SB732.6.M65 Positive regulators of opine-inducible promoters in the nopaline and octopine catabolism regions of Ti plasmids. Lintig, J. von; Zanker, H.; Schroder, J. St. Paul, Minn. : APS Press; 1991 Jul. Molecular plant-microbe interactions : MPMI v. 4 (4): p. 370-378; 1991 Jul. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Plasmids; Tumors; Genetic regulation; Genes; Catabolism; Nopaline; Octopine; Transcription; Promoters; Nucleotide sequences; Genetic analysis; Molecular genetics 218 NAL Call. No.: SB950.2.I3I4 The potential for bioengineering in disease control. Farrand, S. Urbana, Ill. : Cooperative Extension Service, Univ of Illinois at Urbana-Champaign; 1991. Illinois Agricultural Pesticides Conference summaries of presentations January 8, 9, 10, 1991, Urbana, Illinois / Univ of Illinois at Urbana-Champaign, Coop Ext Serv, in coop with the Illinois Natural History Survey. p. 88-92; 1991. "Proceedings of the 1991 Illinois Agricultural Pesticides Conference," January 8-10, 1991, Urbana, Illinois. Language: English Descriptors: Crop management; Disease control; Plant breeding 219 NAL Call. No.: QH506.E46 The protein encoded by the rolB plant oncogene hydrolyses indole glucosides. Estruch, J.J.; Schell, J.; Spena, A. Oxford, Eng. : IRL Press; 1991 Nov. The EMBO journal - European Molecular Biology Organization v. 10 (11): p. 3125-3128; 1991 Nov. Includes references. Language: English Descriptors: Agrobacterium rhizogenes; Oncogenes; Beta- glucosidase; Glucosides; Hydrolysis Abstract: The rolB gene of Agrobacterium rhizogenes, whose expression stimulates the formation of roots by transformed plant tissues and other growth alterations in transgenic plants, codes for a beta-glucosidase able to hydrolyse indole- beta-glucosides. indeed, we show that extracts of bacteria and/or plant tissue expressing the rolB protein hydrolyse indoxyl-beta-glucoside (plant indican). Because of the structural similarity between indoxyl-beta-glucoside and indole-3-acetyl-beta-glucoside (IAA-beta-glucoside), we propose that the physiological and developmental alterations in transgenic plants expressing the rolB gene could be the result of an increased intracellular auxin activity caused by the release of active auxins from inactive beta-glucosides. Thus two of the oncogenes carried by the T-DNA of the plant pathogen Agrobacterium rhizogenes (rolB and rolC) perturb plant growth and development by coding for beta-glucosidases with distinct specificities. Whereas the rolC beta-glucosidase releases cytokinins from their glucoside conjugates, the rolB encoded protein hydrolyses indole-glucosides. The combined action of these two genes therefore is expected to modulate the intracellular concentration of two of the main growth factors active in plants. 220 NAL Call. No.: 448.3 AP5 Pseudomonas stutzeri YPL-1 genetic transformation and antifungal mechanism against Fusarium solani, an agent of plant root rot. Lim, H.S.; Kim, Y.S.; Kim, S.D. Washington, D.C. : American Society for Microbiology; 1991 Feb. Applied and environmental microbiology v. 57 (2): p. 510-516. ill; 1991 Feb. Includes references. Language: English Descriptors: Fusarium solani; Root rots; Pseudomonas; Strains; Genetic transformation; Enzymes; Lysis; Mycelium; Growth; Biological control agents; Microbial pesticides Abstract: An actively antagonistic bacterium that could be used as a biocontrol agent against Fusarium solani, which causes root rots with considerable losses in many important crops, was isolated from a ginseng rhizosphere and identified as a strain of Pseudomonas stutzeri. In several biochemical tests with culture filtrates of P. stutzeri YPL-1 and in mutational analyses of antifungal activities of reinforced or defective mutants, we found that the anti-F. solani mechanism of the bacterium may involve a lytic enzyme rather than a toxic substance or antibiotic. P. stutzeri YPL-1 produced extracellular chitinase and laminarinase when grown on different polymers such as chitin, laminarin, or F. solani mycelium. These lytic extracellular enzymes markedly inhibited mycelial growth rather than spore germination and also caused lysis of F. solani mycelia and germ tubes. Scanning electron microscopy revealed degradation of the F. solani mycelium. Abnormal hyphal swelling and retreating were caused by the lysing agents from P. stutzeri YPL-1, and a penetration hole was formed on the hyphae in the region of interaction with the bacterium; the walls of this region were rapidly lysed, causing leakage of protoplasm. Genetically bred P. stutzeri YPL-1 was obtained by transformation of the bacterium with a broad-host-range vector, pKT230. Also, the best conditions for the transformation were investigated. 221 NAL Call. No.: 448.3 J82 Pseudomonas syringae pv. phaseolicola genomic clones harboring heterologous DNA sequences suppress the same phaseolotoxin- deficient mutants. Kamdar, H.V.; Rowley, K.B.; Clements, D.; Patil, S.S. Washington, D.C. : American Society for Microbiology; 1991 Feb. Journal of bacteriology v. 173 (3): p. 1073-1079. ill; 1991 Feb. Includes references. Language: English Descriptors: Phaseolus vulgaris; Pseudomonas syringae pv. phaseolicola; Phaseolotoxin; Genes; Mutants; Dna; Nucleotide sequences; Clones Abstract: Cosmid cloning and mutagenesis were used to identify genes involved in the production of phaseolotoxin, the chlorosis-inducing phytotoxin of Pseudomonas syringae pv. phaseolicola, the causal agent of halo blight of bean (Phaseolus vulgaris L.). Eight stable clones were isolated from a genomic cosmid library by en masse mating to 10 ethyl methanesulfonate (EMS)-induced Tox- mutants. In cross-matings, each suppressed all 10 mutants as well as an additional 70 EMS-induced Tox- mutants (and one UV-induced Tox- mutant). On the basis of restriction endonuclease analysis and hybridization studies, the clones were grouped into three classes. Clones in a particular class shared common fragments, whereas clones in different classes did not. Clones from class I (but not classes II and III) also suppressed Tns-induced Tox- mutants. Interposon mutagenesis and marker exchange of a representative clone from class III into the wild-type genome did not alter its Tox- phenotype, indicating that this clone does not harbor structural or regulatory genes involved in phaseolotoxin production. We suggest that the genome of P. syringae pv. phaseolicola contains a "hot spot" in one of the functions involved in toxin production which is affected by EMS and UV and that heterologous clones are able to suppress the Tox- phenotype because their inserts encode products that are able to substitute for the product of the mutated gene. Alternatively, the inserts may contain sequences which titrate a repressor protein. In either case, the data suggest that suppression of EMS-and UV-induced mutants occurs when heterologous clones are present in multiple copies. 222 NAL Call. No.: 448.3 J823 Purification of the acidic pectate lyase and nucleotide sequence of the corresponding gene (pelA) of Erwinia chrysanthemi strain 3937. Favey, S.; Bourson, C.; Bertheau, Y.; Kotoujansky, A.; Boccara, M. Reading : Society for General Microbiology; 1992 Mar. The Journal of general microbiology v. 138 (pt.3): p. 499-508; 1992 Mar. Includes references. Language: English Descriptors: Erwinia chrysanthemi; Pectate lyase; Isoenzymes; Genes; Dna; Nucleotide sequences; Amino acid sequences; Pathogenesis-related proteins; Purification; Characterization; Enzyme activity; Physicochemical properties Abstract: The pelA gene from Erwinia chrysanthemi strain 3937, which encodes the acidic pectate lyase, PLa, has been sequenced and characterized. The structural gene consists of a 1179 bp open reading frame encoding a polypeptide of 41555 Da, which includes an N-terminal signal peptide. The deduced amino acid sequence shows a protein very similar to some PLs already sequenced. Cloning of the pelA gene behind the lacZ promoter of the vector pTZ19R allowed overexpression of PLa into a derivative of strain 3937 deleted of the other pel genes. The mature protein was obtained in milligram amounts from the supernatant of this strain and at homogeneous purity after two purification steps. Its biochemical properties were similar to those of other PLs. Polyclonal antibodies raised against the purified PLa cross-reacted with the basic pectate lyase PLd, but not with PLe. The role of PLa in pathogenicity is discussed. 223 NAL Call. No.: QL391.N4R4 Quantitative ELISA for the detection of potato cyst nematodes in soil samples. Schots, A.; Gommers, F.J.; Egberts, E. Montrouge : Gauthier-Villars; 1992. Fundamental and applied nematology v. 15 (1): p. 55-61; 1992. Includes references. Language: English Descriptors: Solanum tuberosum; Globodera rostochiensis; Globodera pallida; Detection; Soil; Samples; Elisa; Monoclonal antibodies 224 NAL Call. No.: SB599.P45 Rapid induction of systemic resistance in cucumber by Pseudomonas syringae pv. syringae. Smith, J.A.; Hammerschmidt, R.; Fulbright, D.W. London : Academic Press; 1991 Mar. Physiological and molecular plant pathology v. 38 (3): p. 223-235; 1991 Mar. Includes references. Language: English Descriptors: Cucumis sativus; Pseudomonas syringae pv. syringae; Disease resistance; Induced resistance; Enzyme activity; Peroxidase; Hypersensitivity; Mutants; Plasmids; Vectors; Genetic transformation; Genetic regulation; Pseudomonas syringae pv. lachrymans; Colletotrichum orbiculare Abstract: Inoculation of the first leaf of cucumber with Pseudomonas syringae pv. syringae (wheat isolate) elicited a rapid hypersensitive response and also induced systemic resistance to Colletotrichum lagenarium. Systemic increases in peroxidase activity and resistance were observed within 1 day of inoculation with P. syringae pv. syringae. The induction of systemic resistance and peroxidase activity by P. syringae pv. syringae was at least 4 days faster than that observed for the cucumber pathogen Pseudomonas syringae pv. lachrymans. Detaching the leaf inoculated with P. syringae pv. syringae at intervals after inoculation demonstrated that the signal(s) involved in systemic induced resistance and increases in peroxidase was generated within 6 h after the inducing inoculation and before the development of visible necrosis. Tn5 mutants of P. syringae pv. syringae, selected for their inability to induce the hypersensitive response and systemic peroxidase activity in cucumber, had also lost their ability to elicit systemic disease resistance in cucumber and cause disease on wheat. A genomic clone was isolated from a library of P. syringae pv. syringae which restored the ability of both mutants to induce the hypersensitive response, systemic disease resistance and peroxidase activity. The rapidity and level of resistance induced by P. syringae pv. syringae suggest that this organism may be useful in future studies on the nature of systemic signaling and the regulation of induced resistance in cucurbits. 225 NAL Call. No.: TP248.65.F66F66 Raw materials: introducting pest resistance in plants to create "green" raw materials. Stiekema, W.J. New York, N.Y. : Marcel Dekker, Inc.; 1991. Food biotechnology v. 5 (3): p. 229-237; 1991. Includes references. Language: English Descriptors: Crop production; Biotechnology; Genetic engineering; Pest resistance 226 NAL Call. No.: 442.8 Z34 Recombination at the Rp1 locus of maize. Hulbert, S.H.; Bennetzen, J.L. Berlin, W. Ger. : Springer International; 1991 May. M G G : Molecular and general genetics v. 226 (3): p. 377-382; 1991 May. Includes references. Language: English Descriptors: Zea mays; Puccinia sorghi; Loci; Recombination; Genetic resistance; Rust diseases; Genetic markers; Restriction fragment length polymorphism; Alleles; Duplication; Crossing over; Segregation; Molecular mapping; Gene mapping Abstract: The Rp1 locus of maize determines resistance to races of the maize rust fungus (Puccinia sorghi). Restriction fragment length polymorphism markers that closely flank Rp1 were mapped and used to study the genetic fine structure and role of recombination in the instability of this locus. Susceptible progeny, lacking the resistance of either parent, were obtained from test cross progeny of several Rp1 heterozygotes. These susceptible progeny usually had non- parental genotypes at flanking marker loci, thereby verifying their recombinational origin. Seven of eight Rp1 alleles (or genes) studied were clustered within about 0.2 map units of each other. Rp1(G), however, mapped from 1-3 map units distal to other Rp1 alleles. Rp5 also mapped distally to most Rp1 alleles. Other aspects of recombination at Rp1 suggested that some alleles carry duplicated sequences, that mispairing can occur, and that unequal crossing-over may be a common phenomenon in this region; susceptible progeny from an Rp1(A) homozygote had recombinant flanking marker genotypes, and susceptible progeny from an Rp1(D)/Rp1(F) heterozygote showed both possible nonparental flanking marker genotypes. 227 NAL Call. No.: QH301.N32 Regeneration and transformation experiments in apple. Welander, M.; Maheswaran, G. New York, N.Y. : Plenum Press; 1991. NATO ASI series : Series A : Life sciences v. 210: p. 237-246. ill; 1991. In the series analytic: Woody plant biotechnology / edited by M.R. Ahuja. Proceedings of a Workshop at the Institute of Forest Genetics, USDA Forest Service, October 15-19, 1989, Placerville, California. Includes references. Language: English Descriptors: Malus pumila; Cultivars; Genetic transformation; Agrobacterium tumefaciens 228 NAL Call. No.: QH442.A1G4 Regulation and secretion of an extracellular esterase from Streptomyces scabies. Schottel, J.L.; Hale, V.; Babcock, M.J. Amsterdam : Elsevier Science Publishers; 1992. Gene v. 115 (1/2): p. 27-31; 1992. Paper presented at the "Eighth International Symposium on Biology of Actinomycetes," August 11-16, 1991, Madison, Wisconsin. Includes references. Language: English Descriptors: Streptomyces scabies; Streptomyces; Structural genes; Esterases; Genetic transformation; Gene transfer; Gene expression; Transcription; Secretion; Zinc; Genetic regulation; Binding site; Dna binding proteins; Enzyme activity; Nucleotide sequences; Amino acid sequences Abstract: Production of a heat-stable, extracellular esterase by Streptomyces scabies is regulated by zinc ions. The esterase-encoding gene (est) from S. scabies was cloned and expressed in Streptomyces lividans. In S. lividans, expression of the est gene is also regulated by Zn2+, and the esterase is efficiently secreted in this organism. The sequence of the est gene suggests that a 39-amino acid signal peptide is removed during secretion of this protein. Deletion analysis has indicated that the hydrophobic domain of the signal peptide is required for secretion. Gel retardation assays and DNaseI footprinting using an S-30 protein extract from S. scabies have previously identified a specific 23-bp protein-binding site upstream from the est coding sequence. Deletion of this protein-binding sequence significantly decreased expression of the est gene. 229 NAL Call. No.: SB599.P45 Relationships between electrolyte leakage from Pyrus communis and virulence of Erwinia amylovora. Brisset, M.N.; Paulin, J.P. London : Academic Press; 1991 Jun. Physiological and molecular plant pathology v. 38 (6): p. 443-453; 1991 Jun. Includes references. Language: English Descriptors: Pyrus communis; Infections; Erwinia amylovora; Host parasite relationships; Cell membranes; Leakage; Electrolytes; Ions; Strain differences; Virulence; Mutants; Strains; Transgenics; Erwinia herbicola; Pseudomonas syringae pv. phaseolicola; Pseudomonas syringae pv. tabaci Abstract: One of the first events associated with the interaction between a necrogenic bacterial pathogen and cells of plant tissues is the leakage of electrolytes and nutrients through the plant cell membranes. A technique, used previously to measure electrolyte leakage from bean leaves infiltrated with Pseudomonas syringae pv. syringae, was adapted and used to study the pattern and extent of leakage from pear tissues treated with wild-type strains and transposon mutants of Erwinia amylovora of different levels of virulence. Results showed that electrolyte leakage from pear treated with E. amylovora can be easily and reliably assessed. Furthermore, there is a correlation (with extracellular polysaccharide producing strains) between the level of virulence of the strains and the amount of leaked electrolytes. 230 NAL Call. No.: QH540.S8 Release of genetically-engineered microorganisms in the environment: risk of horizontal genetic-transfer. Hoekstra, W.P.M. New York, N.Y. : Elsevier Science Publishing Company Inc; 1991. Studies in environmental science (42): p. 351-357; 1991. In the series analytic: Environmental biotechnology / edited by A. Blazej and V. Privarova. Proceedings of the International Symposium on Biotechnology, June 27-29, 1990, Bratislava, Czechoslovakia. Includes references. Language: English Descriptors: Microorganisms; Microbial pesticides; Pseudomonas syringae; Genetic engineering; Introduced species; Environmental impact; Ice nucleation; Gene transfer; Genetic transformation 231 NAL Call. No.: 442.8 Z34 Repeats and subrepeats in the intergenic spacer of rDNA from the nematode Meloidogyne arenaria. Vahidi, H.; Honda, B.M. Berlin, W. Ger. : Springer International; 1991 Jun. M G G : Molecular and general genetics v. 227 (2): p. 334-336; 1991 Jun. Includes references. Language: English Descriptors: Meloidogyne arenaria; Ribosomal RNA; Genes; Ribosomal DNA; Repetitive DNA; Nucleotide sequences; Deletions; Recombination Abstract: Ribosomal DNA (rDNA) repeats of the plant-parasitic nematode Meloidogyne arenaria are heterogeneous in size and appear to contain 5S rRNA gene sequences. Moreover, in a recA+ bacterial host, plasmid clones of a 9 kb rDNA repeat show deletion events within a 2 kb intergenic spacer (IGS), between 28S and 5S DNA sequences. These deletions appear to result from a reduction in the number of tandem 129 bp repeats in the IGS. The loss of such repeats might explain how rDNA length heterogeneity, observed in the Meloidogyne genome, could have arisen. Each 129 bp repeat also contains three copies of an 8 bp subrepeat, which has sequence similarity to an element found in the IGS repeats of some plant rDNAs. 232 NAL Call. No.: 440.9 R81J A review of methods for the production and use of monoclonal antibodies to study zoosporic plant pathogens. Hardham, A.R.; Gubler, F.; Duniec, J.; Elliott, J. Oxford : Blackwell Scientific Publications; 1991 Jun. Journal of microscopy v. 162 (3): p. 305-318; 1991 Jun. Includes references. Language: English Descriptors: Phytophthora cinnamomi; Pythium aphanidermatum; Zoospores; Infection; Monoclonal antibodies; Surface antigens; Immunofluorescence; Immunocytochemistry 233 NAL Call. No.: S592.7.A1S6 Rhizosphere growth of Pseudomonas solanacearum genetically altered in extracellular enzyme production. Williamson, J.W.; Hartel, P.G. Exeter : Pergamon Press; 1991. Soil biology and biochemistry v. 23 (5): p. 453-458; 1991. Includes references. Language: English Descriptors: Lycopersicon esculentum; Portulaca oleracea; Pennisetum Americanum; Polygalacturonase; Enzymes; Genes; Plasmids; Mutagenesis; Enzyme activity; Virulence; Growth; Population density; Rhizosphere Abstract: The alteration of specific genes in a bacterium may help in understanding the ecological significance of the genes. In this study we determined the effects of alterations of a single gene (encoding endopolygalacturonase A) and two genes combined (encoding endopolygalacturonase A and endoglucanase) on growth of Pseudomonas solanacearum (the causal agent of bacterial wilt) in soil and in the rhizospheres of host and nonhost plants. The levels of endopolygalacturonase A, or endopolygalacturonase A and endoglucanase production by P. solanacearum were either reduced by insertion mutagenesis or enhanced by increasing the gene copy number with a recombinant plasmid. In addition, changes in virulence of the genetically altered strains were determined by soil inoculation. Under nonsterile conditions, population densities of all strains failed to increase in rhizosphere and nonrhizosphere soils of tomato (Lycopersicon esculentum Mill. cv. Marion), common purslane (Portulaca oleracea L.), and pearl millet [Pennisetum glaucum (L.) R.Br.]. Under gnotobiotic conditions, all strains grew in the rhizosphere of tomato, but the genetically altered strains had < 1-81% lower maximal cell densities, and 9-108% longer generation times. Strains with enhanced enzyme activity were avirulent, possibly because of an impaired ability to grow. Strains with reduced enzyme activity showed little difference in virulence compared to the wild type strain. Our data suggest that a reduction of endopolygalacturonase A, or a reduction of endopolygalacturonase A coupled with an inactivation of endoglucanase production, is of minor importance to the rhizosphere growth of P. solanacearum. 234 NAL Call. No.: 475 EX7 Role of toxins in evolution and ecology of plant pathogenic fungi. Scheffer, R.P. Basel : Birkhauser; 1991 Aug. Experientia v. 47 (8): p. 804-811; 1991 Aug. Literature review. Includes references. Language: English Descriptors: Plant pathogenic fungi; Cochliobolus; Alternaria; Phytotoxins; Evolution; Ecology; Genetics; Literature reviews 235 NAL Call. No.: SB732.6.M65 Role of T-region borders in Agrobacterium host range. Paulus, F.; Huss, B.; Tinland, B.; Herrmann, A.; Canaday, J.; Otten, L. St. Paul, Minn. : APS Press; 1991 Mar. Molecular plant-microbe interactions : MPMI v. 4 (2): p. 163-172; 1991 Mar. Includes references. Language: English Descriptors: Nicotiana tabacum; Nicotiana rustica; Vitis vinifera; Agrobacterium tumefaciens; Host range; Host parasite relationships; Oncogenes; Auxins; Biosynthesis; Genetic regulation; Strains; Strain differences; Tumors; Plasmids; Pathogenicity; Evolution; Gene expression; Nucleotide sequences; Genetic analysis; Molecular genetics 236 NAL Call. No.: 1.98 AG84 Rust-no-more beans: new varieties fend off all 55 known rust- causing fungi. De Quattro, J. Washington, D.C. : The Service; 1992 Feb. Agricultural research - U.S. Department of Agriculture, Agricultural Research Service v. 40 (2): p. 12-14; 1992 Feb. Language: English Descriptors: Phaseolus vulgaris; Rust diseases; Disease resistance; Genetic engineering 237 NAL Call. No.: QH442.A1G4 Sequence analysis of an insertion element, IS1131, isolated from the nopaline-type Ti plasmid of Agrobacterium tumefaciens. Wabiko, H. Amsterdam : Elsevier Science Publishers; 1992. Gene v. 114 (2): p. 229-233; 1992. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Plasmids; Genes; Nucleotide sequences; Transposable elements; Nopaline; Repetitive DNA; Strain differences; Pathogenicity; Restriction mapping; Crown gall Abstract: Transferred DNA (T-DNA) from several nopaline-type Ti plasmids of Agrobacterium tumefaciens was previously shown to be variable in size due to the insertion of extra DNA segments. We found an insertion sequence (named IS1131) in the T-DNA of the strain PO22 and determined the nucleotide (nt) sequence. IS1131 is 2773 bp long, contains four open reading frames, and is flanked by 12-bp perfect inverted repeats (IR). An 8-bp direct repeat was found immediately outside the IR, and represents a target site of integration. Although the IS1131 nt sequence showed a limited degree of similarity to those of the previously reported IS elements of A. tumefaciens and to the central region of T-DNA, the terminal IR of IS1131 were highly homologous (up to 83%) to those of IS66 and IS866, suggesting that these three IS elements are related to each other. A number of IS1131-related copies were found in several pathogenic, as well as nonpathogenic, nopaline-type strains from different plant sources, and were distributed on both chromosomes and plasmids. 238 NAL Call. No.: QH442.A1G4 Sequence analysis of the cellulase-encoding celY gene of Erwinia chrysanthemi: a possible case of interspecies gene transfer. Guiseppi, A.; Aymeric, J.L.; Cami, B.; Barras, F.; Creuzet, N. Amsterdam : Elsevier Science Publishers; 1991. Gene v. 106 (1): p. 109-114; 1991. Includes references. Language: English Descriptors: Erwinia chrysanthemi; Genes; Cellulase; Cloning; Nucleotide sequences; Promoters; Amino acid sequences; Evolution; Gene transfer; Cellulomonas Abstract: The Erwinia chrysanthemi (strain 3937) celY gene encoding the minor endoglucanase (EGY) was sequenced. The analysis of the upstream region allowed us to identify an in vivo active promoter recognized by the NtrA (sigma 54) holoenzyme. No similarity was found between the predicted amino acid (aa) sequences of EGY and either the Er. chrysanthemi major endoglucanase, EGZ, or the Er. carotovora CelS endoglucanase. In contrast, a very high level of identity, both at the nucleotide and the predicted aa levels, was found between celY and an EG-encoding gene from Cellulomonas uda, a Gram+ bacterium taxonomically distant from Er. chrysanthemi. By comparing the molar G + C% of the cellulase-encoding genes and that of Er. chrysanthemi and C. uda chromosomal DNAs, we speculate that celY was transferred from Er. chrysanthemi to C. uda. 239 NAL Call. No.: 448.3 J82 Sequence domains required for the activity of avirulence genes avrB and avrC from Pseudomonas syringae pv. glycinea. Tamaki, S.J.; Kobayashi, D.Y.; Keen, N.T. Washington, D.C. : American Society for Microbiology; 1991 Jan. Journal of bacteriology v. 173 (1): p. 301-307; 1991 Jan. Includes references. Language: English Descriptors: Glycine max; Pseudomonas syringae pv. glycinea; Genes; Disease resistance; Nucleotide sequences; Phenotypes Abstract: avrB and avrC from Pseudomonas syringae pv. glycinea share significant amino acid homology but interact with different soybean resistance genes to elicit the hypersensitive defense reaction. Recombinant genes constructed between avrB and avrC revealed that the central regions were required for avirulence gene activity but the 5' and 3' termini were interchangeable. Recombinants involving the central regions did not yield any detectable avirulence gene activity, and no new avirulence phenotypes were observed from any of the chimeric genes. These results suggest that the protein products of avrB and avrC possess catalytic properties that are required for the avirulence phenotypes. 240 NAL Call. No.: 500 N21P Sequence identity in the nick regions of IncP plasmid transfer origins and T-DNA borders of Agrobacterium Ti plasmids. Waters, V.L.; Hirata, K.H.; Pansegrau, W.; Lanka, E.; Guiney, D.G. Washington, D.C. : The Academy; 1991 Feb15. Proceedings of the National Academy of Sciences of the United States of America v. 88 (4): p. 1456-1460; 1991 Feb15. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Dna sequencing; Molecular genetics; Mutagenesis; Nucleotide sequences; Plasmids 241 NAL Call. No.: QK710.P62 Sequence of Agrobacterium tumefaciens biotype III auxin genes. Bonnard, G.; Vincent, F.; Otten, L. Dordrecht : Kluwer Academic Publishers; 1991 Apr. Plant molecular biology : an international journal on fundamental research and genetic engineering v. 16 (4): p. 733-738; 1991 Apr. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Plasmids; Genes; Nucleotide sequences; Amino acid sequences; Biotypes; Octopine; Amino acid derivatives; Evolution 242 NAL Call. No.: QK710.P62 Sequence of the iaa and ipt region of different Agrobacterium tumefaciens biotype III octopine strains: reconstruction of octopine Ti plasmid evolution. Paulus, F.; Canaday, J.; Vincent, F.; Bonnard, G.; Kares, C.; Otten, L. Dordrecht : Kluwer Academic Publishers; 1991 Apr. Plant molecular biology : an international journal on fundamental research and genetic engineering v. 16 (4): p. 601-614; 1991 Apr. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Plasmids; Genes; Nucleotide sequences; Amino acid sequences; Evolution; Strain differences; Cloning; Gene transfer; Octopine; Amino acid derivatives; Iaa; Biosynthesis; Restriction mapping; Transcription; Genetic transformation; Kalanchoe daigremontiana; Rooting Abstract: The TA regions of biotype Ill octopine/cucumopine (OC) Ti plasmids are closely related to theTL region of the biotype I octopine Ti plasmids pTiAch5 andpTi15955. Sequence analysis shows that the limited and wide host range biotype III OC TA regions are derived from acommon ancestor structure which lacked the 6a gene found in the biotype I octopine TL region. TheTA region of the wide host range OC Ti plasmids has conserved most of the original TL-like structure.In most wide host range OC isolates the TA-iaaH gene is inactivated by the insertion of an IS866element. However, the TA region of the wide host range isolate Hm1 carries an intact TA-iaaH gene. Thisgene encodes a biologically active product, as shown by root induction tests and indole-3-aceticacid measurements. The limited host range OC Ti plasmids pTiAB3 and pTiAg57 haveshorter TA regions which are derived from a wide host range TA region. The AB3 type arose byan IS868-mediated, internal TA region deletion which removed the iaa genes and part of the ipt gene andleft a copy of IS868 at the position of the deleted fragment. The pTiAB3 iaa/ipt deletion was followedby insertion of a second IS element, IS869, immediately 3' of the ipt gene. pTiAg57 underwent the sameiaa- ipt deletion as pTiAB3, but lacks the IS868 and IS869 elements. Analysis of the various TA region structures provides a detailedinsight into the evolution of the biotype Ill OC strains. 243 NAL Call. No.: QK600.E9 Sexual crosses of the homothallic fungus Gaeumannomyces graminis var. tritici based on use of an auxotroph obtained by transformation. Pilgeram, A.L.; Henson, J.M. Orlando, Fla. : Academic Press; 1992 Mar. Experimental mycology v. 16 (1): p. 35-43; 1992 Mar. Includes references. Language: English Descriptors: Gaeumannomyces graminis; Genetic transformation; Genes; Oxidoreductases; Linkage; Segregation; Crosses; Genetic markers; Ascospores; Benomyl; Fungicide tolerance; Drug resistance; Antineoplastic agents; Nutrient requirements; Nicotinic acid; Pathogenicity; Fungal diseases; Triticum aestivum 244 NAL Call. No.: 500 N21P A short C-terminal sequence is necessary and sufficient for the targeting of chitinases to the plant vacuole. Neuhaus, J.M.; Sticher, L.; Meins, F. Jr; Boller, T. Washington, D.C. : The Academy; 1991 Nov15. Proceedings of the National Academy of Sciences of the United States of America v. 88 (22): p. 10362-10366; 1991 Nov15. Includes references. Language: English Descriptors: Cucumis sativus; Nicotiana sylvestris; Nicotiana tabacum; Plant secretions; Vacuoles; Amino acid sequences; Chitinase; Defense mechanisms; Disease resistance; Enzyme activity; Fungal diseases; Gene expression; Polypeptides Abstract: Tobacco contains different isoforms of chitinase (EC 3.2.1.14), a hydrolase thought to be involved in the defense against pathogens. Deduced amino acid sequences for putatively vacuolar, basic chitinases differ from the homologous extracellular, acidic isoforms by the presence of a C-terminal extension. To examine the role of this C-terminal extension in protein sorting, Nicotiana silvestris plants were stably transformed with chimeric genes coding for tobacco basic chitinase A with and without the seven C-terminal amino acids. In plants expressing unmodified chitinase A, the enzyme activity was low in the intercellular wash fluid but high in protoplasts and isolated vacuoles. In contrast, in plants expressing mutant chitinase lacking the C terminus, the activity was high in the intercellular wash fluid but low in protoplasts. N. silvestris plants were also transformed with similar constructions coding for a structurally unrelated, extracellular cucumber chitinase. In plants expressing unmodified cucumber chitinase, its activity was present in the intercellular wash fluid and absent from protoplasts. In plants expressing cucumber chitinase with the C-terminal extension from tobacco chitinase A, activity was low in intercellular wash fluids but high in protoplasts and vacuoles. These results demonstrate that the C-terminal extension of tobacco chitinase A is necessary and sufficient for the vacuolar localization of chitinases and, therefore, that it comprises a targeting signal for plant vacuoles. 245 NAL Call. No.: QH426.C8 A single amino-acid substitution in the beta-tubulin gene of Neurospora confers both carbendazim resistance and diethofencarb sensitivity. Fujimura, M.; Oeda, K.; Inoue, H.; Kato, T. Berlin, W. Ger. : Springer International; 1992. Current genetics v. 21 (4/5): p. 399-404; 1992. Includes references. Language: English Descriptors: Neurospora crassa; Loci; Tubulin; Genes; Induced mutations; Mutants; Carbendazim; Carbamate pesticides; Fungicides; Fungicide tolerance; Fungicidal properties; Nucleotide sequences; Segregation; Amino acid sequences Abstract: Two MBC-resistant mutants of Neurospora crassa, F914 and F939, were sensitive to diethofencarb at a concentration of 0.1 microgram/ml, while the wild-type strain and other MBC-resistant mutants showed resistance to diethofencarb at a concentration of 100 microgram/ml. Genetic analysis suggested that the mutations in these two strains were closely linked to the Bml locus which codes for beta- tubulin. When the wild-type strain was transformed by the cloned beta-tubulin gene of the F914 strain, the transformants showed both MBC resistance and diethofencarb sensitivity. On the other hand, the diethofencarb sensitivity of the F914 strain was cancelled by transformation with the wild-type beta-tubulin gene. DNA sequencing of F914 beta-tubulin revealed that glycine was substituted for glutamic acid at position 198 in the F914 strain. Therefore, a single base change in the beta-tubulin gene was proved to confer both MBC resistance and diethofencarb sensitivity. 246 NAL Call. No.: 448.3 AP5 The solubility of inclusion proteins from Bacillus thuringiensis is dependent upon protoxin composition and is a factor in toxicity to insects. Aronson, A.I.; Han, E.S; McGaughey, W.; Johnson, D. Washington, D.C. : American Society for Microbiology; 1991 Apr. Applied and environmental microbiology v. 57 (4): p. 981-986; 1991 Apr. Includes references. Language: English Descriptors: Bacillus thuringiensis subsp. aizawai; Bacillus thuringiensis subsp. kurstaki; Bacterial insecticides; Nuclear inclusions; Bacterial toxins; Thuringiensin; Precursors; Solubility; Ph; Dna probes; Genes; Dna hybridization; Bioassays; Toxicity; Manduca sexta; Trichoplusia ni; Spodoptera frugiperda; Heliothis virescens; Plodia interpunctella Abstract: Bacillus thuringiensis subsp. aizawai HD133 is one of several strains particularly effective against Plodia interpunctella selected for resistance to B. thuringiensis subsp. kurstaki HD1 (Dipel). B. thuringiensis subsp. aizawai HD133 produces inclusions containing three protoxins, CryIA(b), CryIC, and CryID, and the CryIC protoxin has been shown to be active on resistant P. interpunctella as well as on Spodoptera larvae. The CryIA(b) protoxin is very similar to the major one in B. thuringiensis subsp. kurstaki HD1, and as expected, this protoxin was inactive on resistant P. interpunctella. A derivative of B. thuringiensis subsp. aizawai HD133 which had been cured of a 68-kb plasmid containing the cryIA(b) gene produced inclusions comprising only the CryIC and CryID protoxins. Surprisingly, these inclusions were much less toxic for resistant P. interpunctella and two other Lepidoptera than those produced by the parental strain, whereas the soluble protoxins from these strains were equally effective. In contrast, inclusions from the two strains were about as active as soluble protoxins for Spodoptera frugiperda larvae, so toxicity differences between inclusions may be due to the solubilizing conditions within particular larval guts. Consistent with this hypothesis, it was found that a higher pH was required to solubilize protoxins from inclusions from the plasmid-cured strain than from B. thuringiensis subsp. aizawai HD133, a difference which is probably, attributable to the absence of the CryIA(b) protoxin in the former. The interactions of structurally related protoxins within an inclusion are probably important for solubility and are thus another factor in the effectiveness of B. thuringiensis isolates for particular insect larvae. 247 NAL Call. No.: 448.3 J82 Spontaneous mutation conferring the ability to catabolize mannopine in Agrobacterium tumefaciens. LaPointe, G.; Nautiyal, C.S.; Chilton, W.S.; Farrand, S.K.; Dion, P. Washington, D.C. : American Society for Microbiology; 1992 Apr. Journal of bacteriology v. 174 (8): p. 2631-2639; 1992 Apr. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Mutations; Catabolism; Amino acid derivatives; Plasmids Abstract: Two nopaline-type strains of Agrobacterium tumefaciens, C58 and T37, as well as strain A136, which is a Ti plasmid-cured derivative of strain C58, gave rise to spontaneous mutants that were able to grow on mannopine. The observation of mutagenesis with strain A136 demonstrated that the ability to acquire this new catabolic potential was independent of the presence of a Ti plasmid. The mutants were isolated after 4 weeks of incubation on minimal medium containing mannopine as the sole carbon source. They also utilized mannopinic acid, but not agropine or agropinic acid. In addition, the spontaneous mutant LM136, but not its parent strain A136, degraded many mannityl opine analogs. [(14)C]mannopine disappeared in the presence of LM136 cells which had been pregrown on opine or nonopine substrates. These results suggested that the catabolic system of this mutant was not subject to a stringent regulation. A clone conferring the ability to utilize mannopine on a recipient pseudomonad was selected from a genomic library from both the mutant LM136 and its parent strain. Only the LM136 clone was expressed in the parent Agrobacterium strain A136. Southern analysis showed that the genes for mannopine catabolism in the spontaneous mutants differed from the corresponding Ti plasmid-encoded genes of octopine-type or agropine-type Agrobacterium strains. Cells of LM136 utilized [(14)C]mannopine without generating detectable amounts of intracellular agropine. In contrast, a major fraction of the radioactivity recovered from cells of the octopine-type strain Ach5, after incubation on [14C]mannopine, was in the form of agropine. 248 NAL Call. No.: 448.3 J82 Stimulation of Agrobacterium tumefaciens T-DNA transfer by overdrive depends on a flanking sequence but not on helical position with respect to the border repeat. Shurvinton, C.E.; Ream, W. Washington, D.C. : American Society for Microbiology; 1991 Sep. Journal of bacteriology v. 173 (17): p. 5558-5563; 1991 Sep. Includes references. Language: English Descriptors: Solanum tuberosum; Agrobacterium tumefaciens; Plasmids; Dna; Controlling elements; Nucleotide sequences; Genetic transformation; Virulence; Crown gall; Tumors; Synthetic genes Abstract: T-DNA transfer by Agrobacterium tumefaciens depends on the right border repeat of the T-DNA and is greatly stimulated by overdrive, an adjacent sequence. We report that the function of overdrive does not depend on helical position with respect to the border repeat. A synthetic 24-bp overdrive and a 12-bp region containing a fully conserved 8-bp core overdrive sequence stimulated virulence equally, but full function required additional bases to the left of the 24-bp sequence. 249 NAL Call. No.: QK710.P62 Stress responses in alfalfa (Medicago sativa L.) 12. Sequence analysis of phenylalanine ammonia-lyase (PAL) cDNA clones and appearance of PAL transcripts in elicitor-treated cell cultures and developing plants. Gowri, G.; Paiva, N.L.; Dixon, R.A. Dordrecht : Kluwer Academic Publishers; 1991 Sep. Plant molecular biology : an international journal on molecular biology, biochemistry and genetic engineering v. 17 (3): p. 415-429; 1991 Sep. Includes references. Language: English Descriptors: Medicago sativa; Colletotrichum lindemuthianum; Multigene families; Phenylalanine ammonia-lyase; Messenger RNA; Cloning; Nucleotide sequences; Amino acid sequences; Gene expression; Cell suspensions; Roots; Stems; Leaves; Flowers; Cell wall components; Disease resistance; Enzyme activity Abstract: An expression library containing cDNAs derived from transcripts from fungal elicitor-treated alfalfa cell suspension cultures was screened with an antiserum raised against phenylalanine ammonia-lyase (PAL) from alfalfa. A single immunoreactive clone was isolated which encoded a full- length PAL cDNA (APAL1) consisting of a 2175 bp open reading frame, 96 bp 5'-untranslated leader and 128 bp 3'-non-coding region. The deduced amino acid sequence was 86.5% similar to that of the PAL2 gene of bean, and encoded a polypeptide of Mr 78865. A second PAL cDNA species was isolated, whose 3'- untranslated region was 86% identical to that of APAL1. Southern blot analysis indicated that PAL is encoded by a small multigene family in alfalfa. PAL transcript levels were rapidly and massively induced, and preceded increased PAL extractable activity, on exposure of alfalfa suspension cells to elicitor from baker's yeast. PAL transcripts were most abundant in roots, stems and petioles during growth and development of alfalfa seedlings. These studies provide the basis for an examination of the developmental and environmental control of a key enzyme of phenylpropanoid synthesis in a plant species which is readily amenable to stable genetic transformation. 250 NAL Call. No.: QK710.P62 Stress responses in alfalfa (Medicago sativa L.). 8. Cis- elements and trans-acting factors for the quantitative expression of a bean chalcone synthase gene promoter in electroporated alfalfa protoplasts. Harrison, M.J.; Choudhary, A.D.; Dubery, I.; Lamb, C.J.; Dixon, R.A. Dordrecht : Kluwer Academic Publishers; 1991 May. Plant molecular biology : an international journal on fundamental research and genetic engineering v. 16 (5): p. 877-890; 1991 May. Includes references. Language: English Descriptors: Medicago sativa; Phaseolus vulgaris; Genetic transformation; Electroporation; Protoplasts; Direct DNAuptake; Gene expression; Naringenin-chalcone synthase; Promoters; Chimeras; Chloramphenicol acetyltransferase; Reporter genes; Position effect; Dna binding proteins; Nucleotide sequences; Binding site; Defense mechanisms; Cell wall components; Colletotrichum lindemuthianum Abstract: A chimeric gene consisting of a bean (Phaseolus vulgaris L.) chalcone synthase (CHS) promoter fused to a bacterial chloramphenicol acetyltransferase (CAT) reporter gene was strongly expressed, and further induced by fungal elicitor, when electroporated into alfalfa (Medicago sativa L.) suspension cell protoplasts. Functional analysis of 5' deletions of the CHS promoter-CAT construct in these protoplasts indicated that the region between -326 and -130 contained both activator and silencer elements. Co- electroporation experiments confirmed that these cis-acting elements were binding sites for functionally active trans factors. In vitro DNase I footprinting revealed four potential binding sites for alfalfa suspension cell nuclear proteins between positions -326 and -130 of the CHS promoter. These sites mapped to regions shown to contain functional cis-acting elements on the basis of the deletion analysis. Three of these sites mapped to previously identified binding sites for bean nuclear proteins. Competition gel retardation analysis using oligonucleotide probes containing binding site sequences revealed sequence-specific binding of alfalfa nuclear proteins to an AT-rich element and a putative GT-1 factor consensus binding sequence. Our results define cis elements and their cognate trans factors functionally active in determining the quantitative expression of a defense response gene in a heterologous transient expression system. 251 NAL Call. No.: QK725.P54 Suppression of the powdery mildew pathogen by chitinase microinjected into barley colecptile epidermal cells. Toyoda, H.; Matsuda, Y.; Yamaga, T.; Ikeda, S.; Morita, M.; Tamai, T.; Ouchi, S. Berlin, W. Ger. : Springer International; 1991. Plant cell reports v. 10 (5): p. 217-220; 1991. Includes references. Language: English Descriptors: Hordeum vulgare; Coleoptiles; Epidermis; Genetic transformation; Streptomyces griseus; Plant pathogenic fungi; Erysiphe graminis; Genetic resistance; Chitinase; Enzyme inhibitors; Pathogenicity Abstract: An exogenous chitinase from Streptomyces griseus was introduced into coleoptile epidermal cells of barley (Hordeum vulgare) by microinjection, and the effect of injected chitinase on the growth or development of the powdery mildew pathogen (Erysiphe graminis f. sp. hordei) was examined. Prior to microinjection, an enzymatic degradation of fungal haustorium, the organ taking nutrients from host plant cells, was examined by treating fixed coleoptile epidermis harboring haustoria with this enzyme. The result showed that haustoria were effectively digested by chitinase, suggesting the effectiveness of chitinase treatment for suppressing the fungal development. Microinjection of chitinase was conducted using living coleoptile tissues inoculated with the pathogen. Epidermal cells in which the haustorial primordia had been formed, or in which the haustoria had matured, were selected as targets for injection. The result clearly indicated that injection at the stage of primordium formation was effective in completely digesting haustoria and suppressing the subsequent formation of secondary hyphae of the pathogen. In microinjection after haustorial maturation, hyphal elongation was considerably suppressed though there was no detectable morphological change in the haustoria. Thus, the present study provides the experimental basis for genetically manipulating barley to produce transgenic plants resistant to the powdery mildew disease. 252 NAL Call. No.: QR1.F44 Survival of genetically engineered Pseudomonas fluorescens in soil in competition with the parent strain. Elsas, J.D. van; Overbeek, L.S. van; Feldmann, A.M.; Dullemans, A.M.; Leeuw, O. de Amsterdam : Elsevier Science Publishers; 1991 Feb. FEMS microbiology letters - Federation of European Microbiological Societies v. 85 (1): p. 53-64. ill; 1991 Feb. Includes references. Language: English Descriptors: Netherlands; Pseudomonas fluorescens; Soil bacteria; Strains; Genetic engineering; Transposable elements; Genetic markers; Growth; Survival; Competitive ability; Population dynamics; Soil sterilization; Soil types (textural) Abstract: The population dynamics of two genetically engineered Pseudomonas fluorescens strains, D5 and C5t, introduced into a loamy sand soil, in competition with a spontaneous antibiotic-resistant mutant of the corresponding wildtype strain was studied. Strain D5 contained an insertion of transposon Tn5 in its genome, whereas strain C5t was obtained by insertion of Tn5::tox, a Tn5-derivative containing a Bacillus thuringiensis var. morrisoni delta-endotoxin gene, into the chromosome using a suicide vector system. Southern hybridization analysis demonstrated the absence of vector sequences, and the presence of single copies of either Tn5 or Tn5::tox in the respective strains. Western blotting and a bio-assay on larvae of Anopheles stephensi suggested the tox gene was functional in clone C5t. Both D5 and C5t were prototrophic and their generation times in minimal medium were slightly below that of the corresponding wild-type strain. Tn 5 and Tn 5::tox were stable in both clones during growth in minimal medium for 16 generations. During growth in competition with the wild-type strain, D5 competed well, however C5t was outcompeted from 50 to below 3% of the population in 40 generations. During growth in competition in the sterile loamy sand, both strains were outcompeted by the parent strain; strain C5t was less competitive than D5. In non-sterile loamy sand, the introduced mixed populations showed a slow decline; both C5t and D5 were outcompeted by the parent strain. The decreased fitness of both modified strains, although significant, was considered to be small in ecological terms. Further, the addition of 10% bentonite clay to the loamy sand resulted in a significant enhancement of survival of the mixed populations, and a stabilization of the proportions between the modified strains and the parent. Finally, there was a trend towards a decrease in the proportion modified strain/parent strain in both mixes in the rhizosphere of wheat. 253 NAL Call. No.: QH506.E46 T-DNA gene 5 of Agrobacterium modulates auxin response by autoregulated synthesis of a growth hormone antagonist in plants. Korber, H.; Strizhov, N.; Staiger, D.; Feldwisch, J.; Olsson, O.; Sandberg, G.; Palme, K.; Schell, J.; Koncz, C. Oxford, Eng. : IRL Press; 1991 Dec. The EMBO journal - European Molecular Biology Organization v. 10 (13): p. 3983-3991; 1991 Dec. Includes references. Language: English Descriptors: Nicotiana tabacum; Agrobacterium tumefaciens; Escherichia coli; Oncogenes; Promoters; Gene expression; Genetic regulation; Tryptophan; Amino acid metabolism; Indoles; Biosynthesis; Auxins; Antagonists; Shoots; Regeneration; Genetic transformation; Transgenics; Molecular mapping; Binding proteins Abstract: Oncogenes carried by the transferred DNA (T-DNA) of Agrobacterium Ti plasmids encode the synthesis of plant growth factors, auxin and cytokinin, and induce tumour development in plants. Other T-DNA genes regulate the tumorous growth in ways that are not yet understood. To determine the function of T- DNA gene 5, its coding region was expressed in Escherichia coli. Synthesis of the gene 5 encoded protein (26 kDa) correlated with a 28-fold increase in conversion of tryptophan to indole-3-lactate (ILA), an auxin analogue. Expression of chimeric gene 5 constructs in transgenic tobacco resulted in overproduction of ILA that enhanced shoot formation in undifferentiated tissues and increased the tolerance of germinating seedlings to the inhibitory effect of externally supplied auxin. Promoter analysis of gene 5 in plants revealed that its expression was inducible by auxin and confined to the vascular phloem cells. cis-regulatory elements required for auxin regulation and phloem specific expression of gene 5 were mapped to a 90 bp promoter region that carried DNA sequence motifs common to several auxin induced plant promoters, as well as a binding site for a nuclear factor, Ax-1. ILA was found to inhibit the auxin induction of the gene 5 promoter and to compete with indole-3-acetic acid (IAA) for in vitro binding to purified cellular auxin binding proteins. It is suggested therefore that ILA autoregulates its own synthesis and thereby modulates a number of auxin responses in plants. 254 NAL Call. No.: 448.3 AP5 Temperature and structural effects on transfer of double- stranded RNA among isolates of the chestnut blight fungus (Cryphonectria parasitica). Friese, C.F.; Allen, M.F.; Martin, R.; Van Alfen, N.K. Washington, D.C. : American Society for Microbiology; 1992 Jun. Applied and environmental microbiology v. 58 (6): p. 2066-2070; 1992 Jun. Includes references. Language: English Descriptors: Castanea dentata; Cryphonectria parasitica; Rna; Cytoplasm; Strains; Hyphae; Temperature Abstract: Cryphonectria parasitica is a unique fungus which can serve as a model for understanding transfer of genes between eukaryotic microorganisms. We studied transfer of double-stranded RNA (dsRNA) between compatible and incompatible strains of C. parasitica to determine whether hyphal types or temperature could restrict that exchange. Hyphal connections between incompatible strains occurred at about 30% of the frequency of connections between compatible strains and differed morphologically. Gel electrophoresis and in situ hybridization confirmed that dsRNA was transferred through substrate hyphae but not through aerial hyphae. Freezing temperatures resulted in the loss of dsRNA from the new mycelium of the donor colony and stimulated the production of virulent pycnidiospores. These temperature and structural restrictions may help to explain the lack of spread of the dsRNA despite its presence in the field. 255 NAL Call. No.: SB732.6.M65 Transcription of the octopine catabolism operon of the Agrobacterium tumor-inducing plasmid pTiA6 is activated by a LysR-type regulatory protein. Habeeb, L.F.; Wang, L.; Winans, S.C. St. Paul, Minn. : APS Press; 1991 Jul. Molecular plant-microbe interactions : MPMI v. 4 (4): p. 379-385; 1991 Jul. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Plasmids; Tumors; Genetic regulation; Genes; Catabolism; Octopine; Transcription; Gene expression; Nucleotide sequences; Amino acid sequences; Genetic analysis; Molecular genetics 256 NAL Call. No.: SB732.6.M65 Transcriptional organization and expression of the large hrp gene cluster of Pseudomonas solanacearum. Arlat, M.; Gough, C.L.; Zischek, C.; Barberis, P.A.; Trigalet, A.; Boucher, C.A. St. Paul, Minn. : APS Press; 1992 Mar. Molecular plant-microbe interactions : MPMI v. 5 (2): p. 187-193; 1992 Mar. The accession number j0370b does not conform to standard format. Includes references. Language: English Descriptors: Pseudomonas solanacearum; Strains; Plant pathogenic bacteria; Genes; Pathogenicity; Genetic analysis; Gene expression; Transcription; Size; Genetic regulation; Gene mapping; Insertional mutagenesis; Nicotiana; Lycopersicon 257 NAL Call. No.: 442.8 Z8 Transfer of resistance to the beet cyst nematode (Heterodera schachtii Schm.) into the Brassica napus L. gene pool through intergeneric somatic hybridization with Raphanus sativus L. Lelivelt, C.L.C.; Krens, F.A. Berlin, W. Ger. : Springer International; 1992. Theoretical and applied genetics v. 83 (6/7): p. 887-894; 1992. Includes references. Language: English Descriptors: Brassica napus var. oleifera; Raphanus sativus; Intergeneric hybridization; Somatic hybridization; Restriction fragment length polymorphism; Protoplast fusion; Direct DNAuptake; Genetic resistance; Heterodera schachtii; Mitochondrial DNA; Recombination; Mitochondrial genetics; Chloroplast genetics; Chromosome number Abstract: An intergeneric somatic hybrid was obtained through PEG-induced protoplast fusion between Brassica napus L. (oil- seed rape, AACC, 2n = 38) and a beet cyst nematode resistant genotype of Raphanus sativus L. (fodder radish, RR, 2n = 18). The hybrid nature of the regenerated plant was confirmed by flow cytometric analysis, RFLP-analysis, and chromosome counts. Southern blot analysis of total DNA using pPhcPS1 (rbc-L) as probe indicated that the somatic hybrid contains chloroplasts of B. napus. The mitochondrial genome of the somatic hybrid was studied more extensively using several probes and restriction enzymes. The results indicate inter- or intraspecific mitochondrial DNA recombination. Resistance to the beet cyst nematode (Heterodera schachtii Schm., BCN) was expressed in the hybrid at a high level. 258 NAL Call. No.: 442.8 Z34 Transformation frequencies are enhanced and vector DNA is targeted during retransformation of Leptosphaeria maculans, a fungal plant pathogen. Farman, M.L.; Oliver, R.P. Berlin, W. Ger. : Springer International; 1992 Jan. M G G : Molecular and general genetics v. 231. (2): p. 243-247; 1992 Jan. Includes references. Language: English Descriptors: Leptosphaeria maculans; Genetic transformation; Plasmids; Vectors; Genomes; Drug resistance; Hygromycin b; Antibiotics; Genetic markers; Protoplasts Abstract: Leptosphaeria maculans, a fungal pathogen of Brassica spp., was successfully transformed with the vector pAN8-1, encoding phleomycin resistance. Protoplasts of a vigorous Phleo(r) transformant were then retransformed using the partially homologous vector, pAN7-1 which encodes hygromycin B resistance. Retransformation of this strain to hygromycin resistance occurred at frequencies that were consistently twofold higher than with the original recipient strain. Linearised pAN7-1 DNA transformed phleomycin-resistant protoplasts at higher frequencies still. All the transformants that were tested retained a phleomycin-resistant phenotype (20/20). Molecular analysis of five transformants generated with circular pAN7-1 DNA indicated that in four cases the pAN7-1 vector had integrated into pAN8-1 sequences. These results suggest that transformation frequencies in L. maculans are limited by the ability of vector DNA to integrate into the genome. Hence, construction of strains with target sites for integration may prove to be a generally useful method for improving transformation frequencies of poorly characterised filamentous fungi, particularly when using heterologous vectors. This would greatly facilitate the identification of genes by transfer of gene libraries and the standardisation of chromosomal location effects in studies of expression of nested promoter deletions. 259 NAL Call. No.: QH301.N32 Transformation of Populus--from system development to field plantings. Klopfenstein, N.B.; Thornburg, R.W.; McNabb, H.S. Jr; Hall, R.B.; Hart, E.R.; Chun, Y.W.; Kernan, A.; Shi, N.Q. New York, N.Y. : Plenum Press; 1991. NATO ASI series : Series A : Life sciences v. 210: p. 357-358; 1991. In the series analytic: Woody plant biotechnology / edited by M.R. Ahuja. Proceedings of a Workshop at the Institute of Forest Genetics, USDA Forest Service, October 15-19, 1989, Placerville, California. Includes references. Language: English Descriptors: Populus alba; Populus grandidentata; Hybrids; Gene expression; Genetic transformation; Agrobacterium tumefaciens; Disease resistance; Pest resistance 260 NAL Call. No.: QK600.E9 Transformation of the fungus Pyrenopeziza brassicae, cause of light leaf spot of brassicas, and complementation of mutants using a genomic library. Ball, A.M.; Sawczyc, M.K.; Ashby, A.M.; Ingram, D.S.; Johnstone, K. Duluth, Minn. : Academic Press; 1991 Sep. Experimental mycology v. 15 (3): p. 243-254; 1991 Sep. Includes references. Language: English Descriptors: Pyrenopeziza brassicae; Genetic transformation; Protoplasts; Plasmids; Direct DNAuptake; Mutants; Complementation; Dna libraries; Pathogenicity; Leaf spotting; Brassica campestris var. oleifera 261 NAL Call. No.: 448.3 J82 Transformation of the gram-positive bacterium Clavibacter xyli subsp. cynodontis by electroporation with plasmids from the IncP incompatibility group. Metzler, M.C.; Zhang, Y.P.; Chen, T.A. Washington, D.C. : American Society for Microbiology; 1992 Jul. Journal of bacteriology v. 174 (13): p. 4500-4503; 1992 Jul. Includes references. Language: English Descriptors: Clavibacter xyli; Plasmids; Genetic transformation; Electroporation Abstract: We report the transformation of a gram-positive bacterium, Clavibacter xyli subsp. cynodontis, with several plasmids in the IncP incompatibility group from gram-negative bacteria. Our results suggest that IncP plasmids may be transferable to other gram-positive organisms. After optimizing electroporation parameters, we obtained a maximum of 2 X 10(5) transformants per microgram of DNA. The availability of a transformation system for this bacteria will facilitate its use in indirectly expressing beneficial traits in plants. 262 NAL Call. No.: SB732.6.M65 Transformation of the oomycete pathogen, Phytophthora infestans. Judelson, H.S.; Tyler, B.M.; Michelmore, R.W. St. Paul, Minn. : APS Press; 1991 Nov. Molecular plant-microbe interactions : MPMI v. 4 (6): p. 602-607; 1991 Nov. Includes references. Language: English Descriptors: Solanum tuberosum; Lycopersicon esculentum; Phytophthora infestans; Plant pathogenic fungi; Genetic transformation; Gene transfer; Vectors; Plasmids; Drug resistance; Marker genes; Hygromycin b; Gene expression; Pathogenicity 263 NAL Call. No.: 448.3 J82 Transformation of the phytopathogenic bacterium Clavibacter michiganense subsp. michiganense by electroporation and development of a cloning vector. Meletzus, D.; Eichenlaub, R. Washington, D.C. : American Society for Microbiology; 1991 Jan. Journal of bacteriology v. 173 (1): p. 184-190. ill; 1991 Jan. Includes references. Language: English Descriptors: Clavibacter michiganensis subsp. michiganensis; Genetic transformation; Electroporation; Genetic engineering Abstract: We constructed a cloning vector for use in the plant pathogenic bacterium Clavibacter michiganense subsp. michiganense. The vector pDM100 consists of a 3.2-kb restriction fragment of the Clavibacter plasmid pCM1 joined to a pBR325 derivative carrying the neomycin phosphotransferase of transposon Tn5 and the gentamicin acetyltransferase of Tn1696. Both antibiotic resistance genes are efficiently expressed in C. michiganense subsp. michiganense. Although polyethylene glycol-mediated transfection of spheroplasts with the DNA of the C. michiganense subsp. michiganense-specific bacteriophage CMP1 yielded about 3 X 10(3) transfectants per microgram of DNA, in transformations with plasmid DNA only a very few transformants were obtained. However, the transformation efficiency could be improved by electroporation of intact cells, giving about 2 X 10(3) transformants per microgram of plasmid DNA. Since a transformation procedure and a cloning vector are now available, pathogenicity in C. michiganense subsp. michiganense can now be analyzed genetically. 264 NAL Call. No.: QH426.C8 Transformation of Trichoderma species with dominant selectable markers. Ulhoa, C.J.; Vainstein, M.H.; Peberdy, J.F. Berlin, W. Ger. : Springer International; 1992. Current genetics v. 21 (1): p. 23-26; 1992. Includes references. Language: English Descriptors: Trichoderma hamatum; Trichoderma harzianum; Genetic transformation; Genetic markers; Marker genes; Escherichia coli; Phosphotransferases; Hygromycin b; Neurospora crassa; Tubulin; Drug resistance; Fungicide tolerance; Benomyl; Protoplasts; In vitro selection Abstract: We have developed a transformation system for Trichoderma hamatum and Trichoderma harzianum Rifai, using dominant markers for selection based on the Escherichia coli hygromycin B phosphotransferase gene (hph) and the beta- tubulin gene (bml) from Neurospora crassa, respectively. Transformation frequencies and protoplast regeneration were low in both species. All the T. hamatum hygromycin-resistant transformants analysed were mitotically stable, in contrast to those of T. harzianum derived by benomyl resistance, in which only 50% of the transformants analysed were stable. Molecular analysis of transformants showed the integration of the transforming DNA into the genome and indicated that the number and sites of integration varied among the transformants. 265 NAL Call. No.: 470 SCI2 Transgenic plants with enhanced resistance to the fungal pathogen Rhizoctonia solani. Broglie, K.; Chet, I.; Holliday, M.; Cressman, R.; Biddle, P.; Knowlton, S.; Mauvais, C.J.; Broglie, R. Washington, D.C. : American Association for the Advancement of Science; 1991 Nov22. Science v. 254 (5035): p. 1194-1197; 1991 Nov22. Includes references. Language: English Descriptors: Nicotiana tabacum; Brassica; Rhizoctonia solani; Transgenics; Genetic resistance Abstract: The production of enzymes capable of degrading the cell walls of invading phytopathogenic fungi is an important component of the defense response of plants. The timing of this natural host defense mechanism was modified to produce fungal-resistant plants. Transgenic tobacco seedlings constitutively expressing a bean chitinase gene under control of the cauliflower mosaic virus 35S promoter showed an increased ability to survive in soil infested with the fungal pathogen Rhizoctonia solani and delayed development of disease symptoms. 266 NAL Call. No.: QH426.C8 Transient expression of genes in the oomycete Phytophthora infestans using Bremia lactucae regulatory sequences. Judelson, H.S.; Michelmore, R.W. Berlin, W. Ger. : Springer International; 1991. Current genetics v. 19 (6): p. 453-459; 1991. Includes references. Language: English Descriptors: Bremia lactucae; Phytophthora infestans; Genetic transformation; Gene expression; Beta-glucuronidase; Reporter genes; Vectors; Plant pathogenic fungi Abstract: Vectors containing fusions between the reporter gene beta-glucuronidase (GUS) and transcriptional regulatory signals from the ham34 and hsp70 genes of the oomycete pathogen, Bremia lactucae, were introduced into protoplasts of the related fungus Phytophthora infestans. Transient expression of the GUS gene was detected when DNA was introduced into protoplasts of P. infestans by treatments with polyethylene glycol and CaCl(2), with cationic liposomes, or by electroporation. After optimization of each procedure, using the transient expression assays, cationic liposomes were identified as the superior method for DNA uptake. Vectors containing the 5'hsp70 sequences and 3'ham34 sequences resulted in the maximum level of GUS activity. The identification of functional vectors for transformation, and of optimal methods for introducing DNA, should assist in achieving stable transformation of P. infestans and other oomycete the fungi. 267 NAL Call. No.: 448.8 C162 Transposon Tn5-259 mutagenesis of Pseudomonas cepacia to isolate mutants deficient in antifungal activity. Jayaswal, R.K.; Fernandez, M.A.; Visintin, L.; Upadhyay, R.S. Ottawa : National Research Council of Canada; 1992 Apr. Canadian journal of microbiology v. 38 (4): p. 309-312; 1992 Apr. Includes references. Language: English Descriptors: Plant pathogenic fungi; Pseudomonas cepacia; Mutants; Mutagenesis; Antifungal agents; Biological control agents 268 NAL Call. No.: SB732.6.M65 The TR-DNA region carrying the auxin synthesis genes of the Agrobacterium rhizogenes agropine-type plasmid pRiA4: nucleotide sequence analysis and introduction into tobacco plants. Camilleri, C.; Jouanin, L. St. Paul, Minn. : APS Press; 1991 Mar. Molecular plant-microbe interactions : MPMI v. 4 (2): p. 155-162; 1991 Mar. Includes references. Language: English Descriptors: Nicotiana tabacum; Agrobacterium rhizogenes; Genes; Auxins; Biosynthesis; Genetic regulation; Plasmids; Nucleotide sequences; Genetic analysis; Gene expression; Transgenics; Amino acid sequences; Comparisons; Agrobacterium tumefaciens; Pseudomonas syringae pv. savastanoi 269 NAL Call. No.: 448.3 B13 Two-way chemical signaling in Agrobacterium-plant interactions. Winans, S.C. Washington, D.C. : American Society for Microbiology; 1992 Mar. Microbiological reviews v. 56 (1): p. 12-31; 1992 Mar. Literature review. Includes references. Language: English Descriptors: Agrobacterium; Plant pathology; Chemotaxis; Genetics; Dna; Gene expression; Literature reviews 270 NAL Call. No.: 448.3 J823 Unique DNA plasmid pRS64 associated with chromosomal DNAs of the platn pathogenic fungus Rhizoctonia solani. Wako, T.; Ishikawa, T.; Hashiba, T. Reading : Society for General Microbiology; 1991 Dec. The Journal of general microbiology v. 137 (pt.12): p. 2817-2821; 1991 Dec. Includes references. Language: English Descriptors: Rhizoctonia solani; Anastomosis groups; Chromosomes; Plasmids; Dna; Nucleotide sequences Abstract: Unique DNA sequences homologous to the linear DNA plasmid pRS64 were investigated in chromosomal DNAs of isolates belonging to anastomosis group 4 (AG-4) of the plant pathogenic fungus Rhizoctonia solani. Chromosome-sized DNAs of isolates RI-64 and 1271 of AG-4 were separated into six bands by orthogonal-field-alternation gel electrophoresis and hybridized to a cloned segment of pRS64. A small chromosome- sized DNA band of approximately 1.1 Mb carried the sequences homologous to pRS64 DNA. Sequences homologous to PRS64 were also maintained within the chromosomal DNA of isolate 1271 of AG-4 which does not possess the plasmid. The plasmid showed no homology to the mitochondrial DNA of isolate 1271. The possibility that the linear plasmid pRS64 may act as a transposable genetic element is discussed. 271 NAL Call. No.: QH442.A1G4 The use of African cassava mosaic virus as a vector system for plants. Meyer, P.; Heidmann, I.; Niedenhof, I. Amsterdam : Elsevier Science Publishers; 1992. Gene v. 110 (2): p. 213-217; 1992. Includes references. Language: English Descriptors: Nicotiana tabacum; African cassava mosaic geminivirus; Gene transfer; Vectors; Genetic transformation; Direct DNAuptake; Protoplasts; Transgenics; Genomes Abstract: This paper describes the development of a gene- displacement vector based on DNA1, one of two single stranded circular genomic components of a bipartite geminivirus, African cassava mosaic virus (ACMV). The DNA1 molecules of ACMV were cloned as dimers into a plant transformation vector and the constructs have been integrated into tobacco protoplasts by PEG-mediated DNA transfer. In transgenic plants extrachromosomal copies of DNA1 monomers could be detected. Deletion of the coat protein-encoding gene in chimeric constructs resulted in free DNA1 copies of reduced size, and extrachromosomal recombinant molecules were detected after displacement of the coat protein-encoding region by foreign DNA fragments of comparable size. Due to the absence of the second component of ACMV, DNA2, the transgenic plants are free from viral infection symptoms which allows the establishment of healthy transformants that carry a recombinant construct in an extrachromosomal form. 272 NAL Call. No.: 448.3 AP5 Use of an A-T-rich DNA clone for identification and detection of Peronosclerospora sorghi. Yao, C.L.; Magill, C.W.; Frederiksen, R.A. Washington, D.C. : American Society for Microbiology; 1991 Jul. Applied and environmental microbiology v. 57 (7): p. 2027-2032; 1991 Jul. Includes references. Language: English Descriptors: Zea mays; Sorghum; Peronosclerospora sorghi; Detection; Dna probes; Recombination; Plasmids; Mitochondrial DNA; Adenine; Thymine Abstract: A recombinant plasmid, pMLY12-1, screened from a Peronosclerospora sorghi library hybridizes only to DNA of P. sorghi, or to DNA from leaves infected with P. sorghi, not to DNA of P. sorghi Thailand isolate, P. philippinensis, P. sacchari, or P. maydis. The terminal sequences of the 1.3-kb insert, which appears to contain mitochondrial DNA, are 85% A and T. No polymorphisms were detected when the probe was hybridized to Southern blots containing DNA from P. sorghi pathotype 1, pathotype 3, or a Botswana isolate digested with any of the eight restriction endonucleases tested. The banding patterns were the same whether DNA was extracted directly from the fungus or from infected leaves. 273 NAL Call. No.: 448.3 AP5 Use of bioluminescence for detection of genetically engineered microorganisms released into the environment. Shaw, J.J.; Dane, F.; Geiger, D.; Kloepper, J.W. Washington, D.C. : American Society for Microbiology; 1992 Jan. Applied and environmental microbiology v. 58 (1): p. 267-273; 1992 Jan. Includes references. Language: English Descriptors: Microorganisms; Genetic engineering; Environment; Detection; Release; Xanthomonas campestris pv. campestris; Luminescence; Application methods; Brassica oleracea var. capitata Abstract: The persistence and movement of strain JS414 of Xanthomonas campestris pv. campestris, which was genetically engineered to bioluminesce, were monitored during a limited field introduction. Bioluminescence and traditional dilution plate counts were determined. Strain JS414 was applied to cabbage plants and surrounding soil by mist inoculation, by wound inoculation, by scattering infested debris among plants, and by incorporating bacteria into the soil. Bioluminescent X. campestris pv. campestris was detected in plant samples and in the rhizosphere up to 6 weeks after inoculation. Movement to uninoculated plants was detected on one occasion, but movement from the immediate release area was not detected. Strain JS414 was detected in soil samples beneath mist- and wound- inoculated plants only at intentionally infested locations and in aerial samples only on the day of inoculation. Our bioluminescence methods proved to be as sensitive as plating methods for detecting the genetically engineered microorganisms in environmental samples. Our results demonstrate that transgenic incorporation of the LuxCDABE operon provides a non-labor-intensive, sensitive detection method for monitoring genetically engineered microorganisms in nature. 274 NAL Call. No.: 448.3 J82 Use of cloned DNA methylase genes to increase the frequency of transfer of foreign genes into Xanthomonas campestris pv. malvacearum. De Feyter, R.; Gabriel, D.W. Washington, D.C. : American Society for Microbiology; 1991 Oct. Journal of bacteriology v. 173 (20): p. 6421-6427; 1991 Oct. Includes references. Language: English Descriptors: Xanthomonas campestris pv. malvacearum; Genes; Transferases; Dna; Clones; Plasmids; Escherichia coli; Gene transfer; Gossypium hirsutum Abstract: In vitro-packaged cosmid libraries of DNA from the bacterium Xanthomonas campestris pv. malvacearum were restricted 200- to 1,000-fold when introduced into Mcr+ strains of Escherichia coli compared with restriction in the Mcr- strain HB1O1. Restriction was predominantly associated with the mcrBC+ gene in E. coli. A plasmid (pUFR052) encoding the XmaI and XmaIII DNA methylases was isolated from an X. campestris pv. malvacearum library by a screening procedure utilizing Mcr+ and Mcr- E. coli strains. Transfer of plasmids from E. coli strains to X. campestris pv. malvacearum by conjugation was enhanced by up to five orders of magnitude when the donor cells contained pUFR052 as well as the plasmid to be transferred. Subcloning of PUFR052 revealed that at least two regions of the plasmid were required for full modification activity. Use of such modifier plasmids is a simple, novel method that may allow the efficient introduction of genes into any organism in which restriction systems provide a potent barrier to such gene transfer. 275 NAL Call. No.: QH431.G452 Use of double-ditelosomic and normal chromosome 1D recombinant substitution lines to map Sr33 on chromosome arm 1DS in wheat. Jones, S.S.; Dvorak, J.; Knott, D.R.; Qualset, C.O. Ottawa : National Research Council of Canada; 1991 Aug. Genome v. 34 (4): p. 505-508; 1991 Aug. Includes references. Language: English Descriptors: Triticum aestivum; Triticum; Puccinia graminis; Gene mapping; Gene location; Chromosomes; Genes; Genetic resistance; Rust diseases; Linkage; Gliadin; Glutenins; Recombination; Substitution lines; Segregation; Centromeres Abstract: Chromosome 1D homozygous recombinant substitution lines derived from Triticum aestivum "Chinese Spring" (cross 1) or "Chinese Spring" double-ditelosomic 1D (cross 2) hybridized with a disomic substitution line of Triticum tauschii chromosome 1D in "Chinese Spring" were used to investigate the linkage relationships among Glu-D1, encoding subunits of high molecular weight glutenin storage proteins; Glu-D1, encoding gliadin storage proteins; Sr33, conferring stem rust resistance; and the centromere. Based on analysis of 88 and 91 recombinant substitution lines of crosses 1 and 2, respectively, Sr33 is tightly linked to Gli-D1 on chromosome arm 1DS (5.6 and 7.6% recombination) and less tightly to the centromere (29.6%, cross 2) and to Glu-D1 (40.9 and 39.5%). The order of the loci is Glu-D1--centromere--Sr33--Gli-D1. 276 NAL Call. No.: 464.8 P56 Use of monoclonal antibodies and pathogenicity tests to characterize strains of Xanthomonas campestris pv. dieffbachiae from aroids. Lipp, R.L.; Alvarez, A.M.; Benedict, A.A.; Berestecky, J. St. Paul, Minn. : American Phytopathological Society; 1992 Jun. Phytopathology v. 82 (6): p. 677-682; 1992 Jun. Includes references. Language: English Descriptors: Hawaii; Florida; California; Australia; Araceae; Xanthomonas campestris pv. dieffenbachiae; Pathotypes; Pathogenicity; Strain differences; Monoclonal antibodies; Host range; Virulence 277 NAL Call. No.: 448.3 J82 The virC and virD operons of the Agrobacterium Ti plasmid are regulated by the ros chromosomal gene: analysis of the cloned ros gene. Cooley, M.B.; D'Souza, M.R.; Kado, C.I. Washington, D.C. : American Society for Microbiology; 1991 Apr. Journal of bacteriology v. 173 (8): p. 2608-2616. ill; 1991 Apr. Includes references. Language: English Descriptors: Agrobacterium tumefaciens; Amino acid sequences; Cloning; Crown gall; Dna hybridization; Genetic regulation; Nucleotide sequences; Plasmids; Restriction mapping; Strains; Virulence Abstract: The ros chromosomal gene is present in octopine and nopaline strains of Agrobacterium tumefaciens as well as in Rhizobium meliloti. This gene encodes a 15.5-kda protein that specifically represses the virC and virD operons in the virulence region of the Ti plasmid. The ros gene was cloned from a genomic bank by electroporation and complementation in Agrobacterium cells. Reporter fusion to the ros gene indicates that the level of transcription is controlled in part by autoregulation. A consensus inverted repeat sequence present in the ros promoter and in the virC and virD promoters of pTiC58, pTiA6, and pRiA4b suggests that a specific Ros binding site exists in these promoters. In the virc and virD promoter region, this binding site is within a cluster of vir box consensus sequences in which the VirG protein binds. This suggests possible binding competition between Ros and VirG at the virC and virD promoters. That the Ros protein binds DNA is suggested by the presence of a 'zinc finger' consensus sequence in the protein. 278 NAL Call. No.: 500 N21P virF, the host-range-determining virulence gene of Agrobacterium tumefaciens, affects T-DNA transfer to Zea mays. Jarchow, E.; Grimsley, N.H.; Hohn, B. Washington, D.C. : The Academy; 1991 Dec01. Proceedings of the National Academy of Sciences of the United States of America v. 88 (23): p. 10426-10430. ill; 1991 Dec01. Includes references. Language: English Descriptors: Zea mays; Agrobacterium tumefaciens; Host range; Strains; Virulence; Dna; Transfer; Maize streak geminivirus Abstract: The monocotyledonous plant Zea mays does not develop tumors after inoculation with Agrobacterium tumefaciens and is thus defined as nonhost. Agroinfection, Agrobacterium-mediated delivery of maize streak virus, demonstrates that transferred DNA (T-DNA) transfer to the plant does occur. Nopaline-type Agrobacterium strains such as C58 are efficient in the transfer process whereas the octopine-type strain A6 is unable to transfer T-DNA to maize. This phenotypic difference maps to the tumor-inducing (Ti) plasmid but not to the T-DNA. Steps preceding T-DNA transfer, such as attachment and induction of the virulence genes, were shown to take place in the octopine strain. The nopaline- plasmid-specific locus tzs and the octopine-plasmid-specific locus pinF (virH) are not involved in the strain specificity. However, mutations in the virF locus rendered the octopine strain agroinfectious on maize, whereas such virF-defective octopine strains, when complemented by virF on a plasmid, completely lost their agroinfectivity. We propose that VirF, known to increase the host range of the bacteria in other systems, acts as an inhibitor of T-DNA transfer to maize. 279 NAL Call. No.: 448.3 J82 The virulence-associated chrysobactin iron uptake system of Erwinia chrysanthemi 3937 involves an operon encoding transport and biosynthetic functions. Franza, T.; Expert, D. Washington, D.C. : American Society for Microbiology; 1991 Nov. Journal of bacteriology v. 173 (21): p. 6874-6881; 1991 Nov. Includes references. Language: English Descriptors: Erwinia chrysanthemi; Strains; Iron; Uptake; Siderophores; Membranes; Proteins; Gene expression Abstract: The iron assimilation system of Erwinia chrysanthemi 3937 is mediated by the catechol-type siderophore chrysobactin and the outer membrane transport protein Fct. We generated a variety of subclones in high- and low-copy-number vectors from a wild-type recombinant cosmid shown previously to carry the gene cluster fct-cbsA, cbsB, cbsC, cbsE encoding chrysobactin transport and biosynthetic functions, respectively. We studied their expression in Escherichia coli enterobactin-deficient entA, entB, entC, and entE mutants. This provided evidence that the fct and cbs genes are regrouped within a single genetic unit of ca. 8 kb in the following order: fct, cbsC, cbsE, cbsB, and cbsA. The gene boundaries were determined, and the various recombinant plasmids were expressed in Escherichia coli minicells: CbsA and CbsC enzymatic activities were clearly identified as polypeptides with apparent molecular masses of 32,000 and 38,000, respectively. 280 NAL Call. No.: QH442.G456 White House says recombinant organisms pose no unusual risks to the environment. Eisner, R. New York, N.Y. : Mary Ann Liebert; 1992 Mar15. Genetic engineering news v. 12 (4): p. 1, 15; 1992 Mar15. Language: English Descriptors: Genetic engineering; Recombinant DNA; Microbial pesticides; Crops; Transgenics; Environmental impact; Biotechnology; Environmental policy; Recombinant vaccines 281 NAL Call. No.: 1.9 P69P Witches'-broom, a lethal mycoplasmal disease of lime trees in the Sultanate of Oman and the United Arab Emirates. Garnier, M.; Zreik, L.; Bove, J.M. St. Paul, Minn. : American Phytopathological Society; 1991 Jun. Plant disease v. 75 (6): p. 546-551; 1991 Jun. Includes references. Language: English Descriptors: Oman; United arab emirates; Citrus aurantiifolia; Mycoplasma-like organisms; Mycoplasmal diseases; Spread; Symptomatology; Disease control; Disease distribution; Disease transmission; Etiology; Monoclonal antibodies 282 NAL Call. No.: QH301.N32 Wound-responsive gene expression in poplars. Bradshaw, H.D. Jr; Gordon, M.P. New York, N.Y. : Plenum Press; 1991. NATO ASI series : Series A : Life sciences v. 210: p. 265-268; 1991. In the series analytic: Woody plant biotechnology / edited by M.R. Ahuja. Proceedings of a Workshop at the Institute of Forest Genetics, USDA Forest Service, October 15-19, 1989, Placerville, California. Includes references. Language: English Descriptors: Populus; Gene expression; Hybrids; Injuries; Transcription; Disease resistance; Pest resistance 283 NAL Call. No.: SB732.6.M65 Xanthomonas campestris pv. translucens genes determining host- specific virulence and general virulence on cereals identified by Tn5-gusA insertion mutagenesis. Waney, V.R.; Kingsley, M.T.; Gabriel, D.W. St. Paul, Minn. : APS Press; 1991 Nov. Molecular plant-microbe interactions : MPMI v. 4 (6): p. 623-627; 1991 Nov. Includes references. Language: English Descriptors: Hordeum vulgare; Triticum aestivum; Avena sativa; Triticale; Secale cereale; Gossypium hirsutum; Cultivars; Varietal susceptibility; Xanthomonas campestris pv. translucens; Virulence; Genes; Strains; Strain differences; Host range; Host specificity; Genetic analysis; Insertional mutagenesis; Induced mutations; Mutants; Complementation 284 NAL Call. No.: 442.8 J8224 X-ray crystal structure of the two site-specific mutants His35Gln and His35Leu of Azurin from Pseudomonas aeruginosa. Nar, H.; Messerschmidt, A.; Huber, R. London : Academic Press; 1991 Mar20. Journal of molecular biology v. 218 (2): p. 427-447; 1991 Mar20. Includes references. Language: English Descriptors: Pseudomonas aeruginosa; Mutants; Plant proteins; Induced mutations; Glutamine; Leucine; Electron transfer; Molecular conformation; Crystals; X ray diffraction; Crystallography Abstract: The three-dimensional structures of two site- specific mutants of the blue copper protein azurin from Pseudomonas aeruginosa have been solved by a combination of isomorphous replacement and Patterson search techniques, and refined by energy-restrained least-squares methods. The mutations introduced by recombinant DNA techniques involve residue His35, which was exchange for glutamine and leucine, to probe for its suggested role in electron transfer. The two mutants, His35Gln (H35Q) and His35Leu (H35L), crystallize non- isomorphously in the orthorhombic space group P212121 with unit cell dimensions of a = 109.74 angstrom, b = 99.15 angstrom c = 47.82 angstrom for H35Q, a = 57.82 angstrom, b = 81.06 angstrom, c = 110.03 angstrom for H35L. In each crystal form, there are four molecules in the asymmetric unit. They are arranged as a dimer of dimers in the H35Q case and are distorted from ideal C2 symmetry in H35L. The final crystallographic R-value is 16.3% for 20,747 reflections to a resolution of 2.1 angstrom for H35Q and 17.0% for 32,548 reflections to 1.9 angstrom for H35L. The crystal structures reported here represent the first crystallographically refined structures for azurin from P. aeruginosa. The structure is very similar to that of azurin from Alcaligenes denitrificans. The copper atom is located about 7 angstrom below a hydrophobic surface region and is ligated by five donor groups in a distorted trigonal bipyramidal fashion. The implications for electron transfer properties of the protein are discussed in terms of the mutation site and the packing of the molecules within the tetramer. AUTHOR INDEX Ahl-Goy, P. 135 Aird, E.L.H. 142 Albrecht, H. 11 Alcorn, S.C. 137 Allavena, A. 17 Allen, M.F. 254 Alton, G. 149 Alvarez, A.M. 73, 276 Amselem, J. 172 Anderson, J.B. 188 Anderson, J.J. 137 Andrianov, V.M. 216 Ankenbauer, R.G. 185 Aoyama, T. 52 Arellano, F. 107 Arlat, M. 256 Arnold, W. 130 Aronson, A.I. 246 Ashby, A.M. 88, 260 Astolfi-Filho, S. 81, 94 Atherton, G.T. 181 Ayers, A.R. 160 Aymeric, J.L. 238 Babcock, M.J. 228 Baek, S.R. 121 Bailey, A.M. 125 Bajar, A. 138 Ball, A.M. 88, 260 Banks, G.R. 43 Barash, I. 139 Barber, C.E. 119 Barberis, P.A. 256 Barbosa, P. 84 Barras, F. 238 Barta, T.M. 40 Bauer, D.W. 109 Bavage, A.D. 181 Beck von Bodman, S. 193 Beer, S.V. 95, 109 Beijersbergen, A. 45 Bej, A.K. 2 Bel, A.J.E. van 146 Bellemann, P. 161 Bender, C.L. 46, 77, 207 Benedict, A.A. 73, 276 Bennetzen, J.L. 14, 226 Bent, A. 15 Bent, A.F. 141 Berestecky, J. 276 Bergstrom, G.C. 167 Bernacchia, G. 17 Bernard, R.L. 69 Bertheau, Y. 39, 222 Best, E.A. 185 Betteridge, P. 115 Beyer, P. 25 Bhatt, D. 4 Biddle, P. 265 Binns, A.N. 3, 163 Blaiseau, P.L. A39 Blasco, F. 192 Boccara, M. 222 Boerma, H.R. 24 Bol, J.F. 11 Boller, T. 244 Bolyard, M.G. 169 Bonas, U. 96, 154 Bonde, M.R. 61 Bonnard, G. 241, 242 Boucher, C.A. 256 Bouchez, D. 196 Bouhin, H. 67 Bourson, C. 222 Bouvet, O.M.M. 143 Bove, J.M. 62, 106, 183, 281 Bozin, D. 166 Brackin, J.M. 116 Bradshaw, H.D. Jr 282 Brandes, A. 76 Brandolini, A. 127 Braun, E.J. 64 Brightwell, G. 142 Brisset, M.N. 229 Brlansky, R.H. 201 Broglie, K. 265 Broglie, R. 265 Brooker, J.D. 150 Brown, A.P. 149 Brown, J.W. 206 Brygoo, Y. 39, 108 Bulgakov, V.P. 55 Bull, J. 202 Bunkers, G.J. 97 Burns, R. 63 Burr, T.J. 136, 213, 214 Bush, A.L. 28, 54 Butterworth, J. 70 Cami, B. 238 Camilleri, C. 268 Canaday, J. 89, 156, 235, 242 Caplan, A.B. 102 Carbone, I. 188 Carland, F.M. 34 Casale, W.L. 32 Castle, L.A. 41 Caten, C.E. 153 Cerovic, G. 166 Chambost, J.P. 192 Charles, J.P. 67 Chatterjee, A. 177, 192 Chatterjee, A.K. 98, 177, 192 Chen, C.Y. 30, 49 Chen, T.A. 261 Chet, I. 265 Chiang, D.C. 36 Chilton, W.S. 247 Chiou, C.S. 12 Chiou, S.J. 36 Choudhary, A.D. 205, 250 Christ, B.J. 80 Chu, F.S. 178 Chumley, F.G. 35, 71, 180 Chun, Y.W. 259 Citovsky, V. 191 Civerolo, E.L. 211 Cizeau, J. 8 Clark, E. 139 Clausen, C.A. 51 Cleary, J.M. 162 Clements, D. 221 Close, S.M. 197 Coleman, R.H. 40 Collins, G.B. 4 Collmer, A. 98, 177, 213, 214 Cook, D. 117 Cooley, M.B. 277 Cooley, R.N. 153 Coplin, D.L. 190 Cox, G. 65 Crecy-Lagard, V. de 143 Crespi, M. 102 Cressman, R. 265 Creuzet, N. 238 Crouzet, P. 89 Crowhurst, R.N. 133 Cuppels, D.A. 26 Cutler, K. 22 D'Souza, M.R. 277 Da Costa E Silva, O. 175 Daboussi, M.J. 108, 198 Dale, E.M. 3 Dale, P. 110 Danchin, A. 143 Dane, F. 273 Daniels, M.J. 88, 119 Das, A. 48, 184, 187 Davey, M.R. 204 Davis, M.J. 75 Davis, R.E. 122 De Feyter, R. 16, 201, 274 De Quattro, J. 236 Deakin, W. 1493 Defago, G. 132 Delachambre, J. 67 Delay, D. 8 Delmotte, F.M. 8 Denes, A.S. 99 Deng, S. 123 Denny, T.P. 121 Desjardins, A.E. 151 Desomer, J. 102 Destefano-Beltran, L. 124 Dewar, K. 10 Diaz, R. 118 Dickman, M.B. 103 Dimitrijevic, B. 166 Diner, A.M. 145 Dion, P. 247 Dittapongpitch, V. 50