| cytokinin production by agrobacterium and pseudomonas spp. | the production of cytokinins by plant-associated bacteria was examined by radioimmunoassay. strains producing trans-zeatin were identified in the genera agrobacterium and pseudomonas. agrobacterium tumefaciens strains containing nopaline tumor-inducing plasmids, a. tumefaciens lippia isolates, and agrobacterium rhizogenes strains produced trans-zeatin in culture at 0.5 to 44 micrograms/liter. pseudomonas solanacearum and pseudomonas syringae pv. savastanoi produced trans-zeatin at levels of up t ... | 1987 | 3624204 |
| conserved repeats in diverged ice nucleation structural genes from two species of pseudomonas. | sequence analysis shows that an ice nucleation gene (inaw) from pseudomonas fluorescens is related to the inaz gene of pseudomonas syringae. the two genes have diverged by many amino acid substitutions, and have effectively randomized the third bases of homologous codons. by reference to their potential for change, it is shown that certain conserved features must have been maintained by selection pressure. in particular, their conservation of internal sequence repetition, with three orders of re ... | 1986 | 3774551 |
| in vitro susceptibilities and beta-lactamase production of 53 clinical isolates of branhamella catarrhalis. | we tested 53 clinical isolates of branhamella catarrhalis recovered from patients with respiratory symptoms to determine the susceptibility of the isolates to 25 antimicrobial agents, including the newer beta-lactam antibiotics. of the 53 strains, 46 (86.7%) were beta-lactamase producers. all the strains were susceptible to the majority of the new penicillins and cephalosporins. the combinations of amoxacillin-clavulanic acid and ticarcillin-clavulanic acid were also very active against the beta ... | 1985 | 3873905 |
| exopolysaccharides of the phytopathogen pseudomonas syringae pv. glycinea. | exopolysaccharides (eps) of the soybean pathogen pseudomonas syringae pv. glycinea were isolated from culture filtrates and infected soybean leaves. levan (a polyfructan with a c-2----c-6 backbone and c-2----c-1 branching) or acetylated alginate (a linear polyuronide of c-1----c-4-linked mannuronic and guluronic acids) was isolated from culture filtrates when bacterial strains were grown in a semisynthetic medium containing sucrose or glucose, respectively, as the primary carbon source. acetylat ... | 1986 | 3957873 |
| production of fosfomycin (phosphonomycin) by pseudomonas syringae. | | 1986 | 3759643 |
| regulation of syringomycin synthesis in pseudomonas syringae pv. syringae and defined conditions for its production. | production of the phytotoxin, syringomycin (sr), by pseudomonas syringae pv. syringae strain b301d was regulated by both iron and inorganic phosphate similar to that of many bacterial secondary metabolites. iron concentrations of 2 mumol/l or more in deferrated potato-dextrose broth (pdb) resulted in the production of 1024 sr units/ml, a yield comparable to that produced in non-deferrated pdb. moreover, production of one sr unit required approximately 0.4 ng of available fecl3. no sr was produce ... | 1985 | 3980301 |
| transformation of pseudomonas syringae with nonconjugative r plasmids. | transformation of pseudomonas syringae strains with plasmid dna occurs at a frequency of 1 x 10(-3) to 4 x 10(-9) per recipient cell, depending on the strain, plasmid, and conditions for transformation. r plasmids used successfully in transformation were pr0161 (26 x 10(6) molecular weight) and rsf1010 (5.5 x 10(6) molecular weight). transformation involved growing the recipient cells to approximately 8 x 10(8) colony-forming units per millilitre in 50 ml of a nutrient broth. after washes with a ... | 1981 | 7296409 |
| minimal region necessary for autonomous replication of ptar. | the native 44-kilobase-pair plasmid ptar, discovered in a grapevine strain of agrobacterium tumefaciens, contains a single origin of dna replication confined to a 1.0-kilobase-pair region of the macromolecule. this region (ori) confers functions sufficient for replication in agrobacterium and rhizobium species but not in pseudomonas solanacearum, pseudomonas glumae, pseudomonas syringae pv. savastanoi, xanthomonas campestris pv. campestris, and escherichia coli. ori contains a repa gene that enc ... | 1988 | 3290199 |
| an arabidopsis thaliana lipoxygenase gene can be induced by pathogens, abscisic acid, and methyl jasmonate. | we isolated and characterized a 2.8-kb, full-length, arabidopsis thaliana cdna clone encoding a lipoxygenase. dna sequence analysis showed that the deduced amino acid sequence of the arabidopsis protein is 72 to 78% similar to that of legume seed lipoxygenases. dna blot analysis indicated that arabidopsis contains a single gene, lox1, with appreciable homology to the cdna clone. rna blot analysis showed that the lox1 gene is expressed in arabidopsis leaves, roots, inflorescences, and young seedl ... | 1993 | 7506426 |
| cloning and expression of bacterial ice nucleation genes in escherichia coli. | epiphytic populations of pseudomonas syringae and erwinia herbicola are important sources of ice nuclei that incite frost damage in agricultural crop plants. we have cloned and characterized dna segments carrying the genes (ice) responsible for the ice-nucleating ability of these bacteria. the ice region spanned 3.5 to 4.0 kilobases and was continuous over this region in p. syringae cit7r1. the cloned fragments imparted ice-nucleating activity in escherichia coli. substantial increases in the nu ... | 1985 | 3900043 |
| regulation of 3-indoleacetic acid production in pseudomonas syringae pv. savastanoi. purification and properties of tryptophan 2-monooxygenase. | the oxidative decarboxylation of l-tryptophan to yield 3-indoleacetamide, catalyzed by tryptophan 2-monooxygenase, represents a controlling reaction in the synthesis of indoleacetic acid by pseudomonas savastanoi (pseudomonas syringae pv. savastanoi), a gall-forming pathogen of olive (olea europea l.) and oleander (nerium oleander l.). production of indoleacetic acid is essential for virulence of the bacterium in its hosts. tryptophan 2-monooxygenase was characterized to determine its role in in ... | 1985 | 3997822 |
| structure of the sidechain of lipopolysaccharide from pseudomonas syringae pv. morsprunorum c28. | the sidechain of the lipopolysaccharide from the phytopathogen pseudomonas syringae pv. morsprunorum c28 was shown to be composed of d-rhamnose. using 1h and 13c-nmr spectroscopy, methylation analysis, smith degradation and optical rotation data, the repeat unit was found to have the structure: ----3)-d-rhap-(alpha 1----3)-d-rhap-(alpha 1----2)-d-rhap-(alpha 1---- and a degree of polymerization of approximately 70. attention is drawn to the possible prevalence of d-6-deoxyhexoses in the lipopoly ... | 1985 | 3996404 |
| the inactivation of ornithine transcarbamoylase by n delta-(n'-sulpho-diaminophosphinyl)-l-ornithine. | phaseolotoxin, a tripeptide inhibitor of ornithine transcarbamoylase, is a phytotoxin produced by pseudomonas syringae pv. phaseolicola, the causal agent of halo-blight in beans. in vivo the toxin is cleaved to release n delta-(n'-sulpho-diaminophosphinyl)-l-ornithine, the major toxic chemical species present in diseased leaf tissue. this paper reports on the interaction between n delta-(n'-sulpho-diaminophosphinyl)-l-ornithine and ornithine transcarbamoylase. n delta-(n'-sulpho-diaminophosphiny ... | 1985 | 4015624 |
| detection of two ornithine carbamoyltransferases in a phaseolotoxin-producing strain pseudomonas syringae pv. phaseolicola. | the phaseolotoxin-producing pseudomonas syringae pv. phaseolicola strain 1321 contains two ornithine carbamoyltransferases which differ in resistance to phaseolotoxin. whereas ornithine carbamoyltransferase 1 (oct 1) is inhibited at low concentrations of phaseolotoxin, ornithine carbamoyltransferase 2 (oct 2) is insensitive to phaseolotoxin. the activity of the insensitive enzyme is correlated with the amount of toxin formed. | 1985 | 4087158 |
| nucleotide sequence and organization of copper resistance genes from pseudomonas syringae pv. tomato. | the nucleotide sequence of a 4.5-kilobase copper resistance determinant from pseudomonas syringae pv. tomato revealed four open reading frames (orfs) in the same orientation. deletion and site-specific mutational analyses indicated that the first two orfs were essential for copper resistance; the last two orfs were required for full resistance, but low-level resistance could be conferred in their absence. five highly conserved, direct 24-base repeats were found near the beginning of the second o ... | 1988 | 3372485 |
| cytochromes of pseudomonas syringae. | | 1967 | 6066054 |
| characterization of eight excision plasmids of pseudomonas syringae pv. phaseolicola. | pseudomonas syringae pv. phaseolicola strain lr719 contains a 150 kilobase pair (kb) plasmid pmc7105, stably integrated into its chromosome. occasionally, single colony isolates of this strain contain an excision plasmid. eight unique excision plasmids were selected and characterized by bamhi restriction endonuclease and blot hybridization analyses. these plasmids ranged in size from 35 to 270 kb; the largest contained approximately 130 kb of chromosomal dna sequences. restriction maps of pmc710 ... | 1984 | 6092867 |
| integration and partial excision of a cryptic plasmid in pseudomonas syringae pv. phaseolicola. | a virulent strain of pseudomonas syringae pv. phaseolicola, a pathogen of the common bean phaseolus vulgaris (l.), was shown to harbor a 98-megadalton cryptic plasmid, pmc7105. after exposure of this strain to the plasmid-curing agent mitomycin c, a colony was isolated which had no detectable extrachromosomal dna. hybridization of labeled pmc7105 probe to nitrocellulose filters containing southern-blotted bamhi cleavage products of cellular dna revealed that pmc7105 was integrated into the chrom ... | 1982 | 6290453 |
| transposable element that causes mutations in a plant pathogenic pseudomonas sp. | a 1.3-kilobase-pair dna element, is51, causes a loss of virulence in the plant pathogen pseudomonas syringae pv. savastanoi. this sequence, is51, was first discovered in a plasmid-borne iaam locus, which together with iaah directs the synthesis of a virulence factor, indoleacetic acid. the spontaneous insertion of is51 in iaam resulted in the loss of indoleacetic acid production, attenuation of virulence, and the loss of both enzyme activities coded by iaam and iaah. using a cloned is51 element ... | 1983 | 6304006 |
| transfer of prd1 to pseudomonas syringae and evidence for its integration into the chromosome. | plasmid prd1 was conjugatively transferred from escherichia coli to pseudomonas syringae. subculturing the transconjugate on a medium that selected for prd1-determined his+ kmr resulted in the loss of prd1 as an extrachromosomal element as detected by agarose gel electrophoresis. dna hybridization provided evidence for the integration of prd1 into the p. syringae chromosome. | 1983 | 6358197 |
| integration and excision of pmc7105 in pseudomonas syringae pv. phaseolicola: involvement of repetitive sequences. | the site for integration of pmc7105 into the chromosome of pseudomonas syringae pv. phaseolicola has been mapped to a 2.6-kilobase-pair (kb) bg/ii-ecori fragment on this 150-kb indigenous plasmid. selected excision plasmids resulting from imprecise excision of pmc7105 were used to identify one of the plasmid-chromosome juncture fragments and to characterize the mechanism of recombination from the chromosome. a 14.2-kb bamhi plasmid-chromosome juncture fragment has been identified in pex8060 (234 ... | 1984 | 6321436 |
| [studies on the variability of the phaseolotoxin production by pseudomonas syringae pv. phaseolicola]. | isolation of bacteria from a field of bean plants (phaseolus vulgaris l.) with conspicuous symptoms of halo blight disease resulted in 123 bacterial strains from which 57 were identified as pseudomonas syringae pv. phaseolicola . at 18 degrees c the phaseolotoxin production of the isolated strains differs widely in submerse culture. only few strains produce high amounts of phaseolotoxin being comparable with those of the reference strain 1321, while most of the strains show a low capability of p ... | 1984 | 6428075 |
| conjugal transfer of e. coli f'lac from erwinia chrysanthemi to pseudomonas syringae pv. glycinea and the apparent stable incorporation of the plasmid into the pv. glycinea chromosome. | the e. coli f'lac plasmid was transferred from an erwinia chrysanthemi hfr8 donor to a multiply-auxotrophic, rifampicin-resistant pseudomonas syringae pv. glycinea recipient. transfer occurred at a frequency of approximately 10(-5)/donor. stable transconjugants which were able to utilize lactose as the sole carbon source after several transfers would not donate the f'lac plasmid in detectable frequency to other pv. glycinea or e. coli recipients. the plasmid dna was shown to be integrated into t ... | 1984 | 6394959 |
| ice nucleating activity of pseudomonas syringae and erwinia herbicola. | chemical and biological properties of the ice nucleating sites of pseudomonas syringae, strain c-9, and erwinia herbicola have been characterized. the ice nucleating activity (ina) for both bacteria was unchanged in buffers ranging from ph 5.0 to 9.2, suggesting that there were no essential groups for which a change in charge in this range was critical. the ina of both bacteria was also unaffected by the addition of metal chelating compounds. borate compounds and certain lectins markedly inhibit ... | 1983 | 6848483 |
| purification and some properties of the d-lactate-2-sulphatase of pseudomonas syringae gg. | a soil bacterium grown on propan-2-yl sulphate as sole source of carbon and sulphur yielded extracts containing an enzyme capable of liberating sulphate from racemic lactate-2-sulphate. the enzyme was purified to homogeneity by a combination of streptomycin sulphate precipitation of nucleic acids, batch treatment with deae-cellulose, and chromatography on columns of deae-cellulose, sephacryl s-300 and butyl-agarose. the protein was monomeric with an mr of 55 000-60 000. the enzyme activity was s ... | 1984 | 6497859 |
| sequence of a gene encoding periplasmic pseudomonas syringae ankyrin. | a gene encoding ankyrin (ank) was isolated from a genomic library of the plant pathogen pseudomonas syringae pathovar syringae strain 61 (pss61). the gene encodes an 183-amino-acid (aa) polypeptide which has homology to the 33-aa repeat domain of mammalian ank and ank homologs from other bacteria, animals and plants. | 1995 | 7590314 |
| dynamic model of discontinuous and continuous phaseolotoxin production of pseudomonas syringae pv. phaseolicola. | from experimental data of kinetics of growth, glucose consumption and product formation of pseudomonas syringae pv. phaseolicola the development and parameter estimation of a mathematical model is presented. the model describes the behaviour of both, batch and chemostat culture, as well as for different temperatures. the model is favoured for dynamic optimization studies. maximal productivity is reached in the chemostat for a dilution rate which is only a little bit smaller than the wash out poi ... | 1984 | 6475109 |
| phaseolotoxin transport in escherichia coli and salmonella typhimurium via the oligopeptide permease. | phaseolotoxin [(n delta-phosphosulfamyl)ornithylalanylhomoarginine], a phytotoxic tripeptide produced by pseudomonas syringae pv. phaseolicola that inhibits ornithine carbamoyltransferase, is transported into escherichia coli and salmonella typhimurium via the oligopeptide transport system (opp). mutants defective in oligopeptide permease (opp-) were resistant to phaseolotoxin. spontaneous phaseolotoxin-resistant mutants (toxr) lacked the opp function as evidenced by their cross-resistance to tr ... | 1980 | 6991475 |
| variability among isolates of pseudomonas syringae pv. savastanoi from the phylloplane of the olive. | leaves of three or four different ages were taken from olive plants quarterly in 1974-1980. one thousand and fifty isolates of pseudomonas syringae pv. savastanoi from the phylloplane were tested for virulence to the olive and subjected to numerical phenetic analysis using 60 unit characters. the data were analysed using unweighted average linkage (upgma) and single linkage clustering on the simple matching (ssm) and pattern (sp) coefficients. the isolates obtained from leaves of a given age at ... | 1983 | 6886676 |
| phaseolotoxin-insensitive ornithine carbamoyltransferase of pseudomonas syringae pv. phaseolicola: basis for immunity to phaseolotoxin. | cell-free extracts from phaseolotoxin-producing strains of pseudomonas syringae pv. phaseolicola grown at 18 degrees c, the optimum temperature for phaseolotoxin production, contain an ornithine carbamoyltransferase activity that is insensitive to phaseolotoxin. extracts from the same strains grown at 30 degrees c, a temperature at which little or no detectable phaseolotoxin is produced, and from phaseolotoxin-nonproducing strains contain a phaseolotoxin-sensitive ornithine carbamoyltransferase ... | 1980 | 7380807 |
| bacteriocin production by pseudomonas syringae psw-1 in plant tissue. | the production and activity of syringacin w-1, a particulate bacteriocin made by pseudomonas syringae psw-1, was studied in plant tissue. the bacteriocin is rod shaped, approximately 20 nm wide and 75 nm long, and composed of an outer sheath and inner core. both the producing strain, psw-1, and a sensitive strain, 16, grew within red kidney bean stems. strains psw-1 and 16, or mutants derived from them, were injected into bean stems singly or in mixtures. all singly inoculated strains grew well. ... | 1982 | 7116232 |
| nasal antibodies against gram-negative bacteria in cotton-mill workers. | antibody activity to cotton dust bacteria in the nasal secretions of cotton-mill cardroom workers was studied using the elisa technique. secretion samples were collected by inserting a roll of filter paper into the nasal cavities of the subjects. the amount of secretion was significantly less among cotton-mill workers than workers in a wood factory. no significant differences were seen between byssinotic and nonbyssinotic cotton-mill workers. no significant differences were observed between cott ... | 1982 | 7141716 |
| [serological activity of the carbohydrate-containing substances in pseudomonas syringae 8414]. | | 1980 | 7432211 |
| expression of the stra-strb streptomycin resistance genes in pseudomonas syringae and xanthomonas campestris and characterization of is6100 in x. campestris. | expression of the stra-strb streptomycin resistance (smr) genes was examined in pseudomonas syringae pv. syringae and xanthomonas campestris pv. vesicatoria. the stra-strb genes in p. syringae and x. campestris were encoded on elements closely related to tn5393 from erwinia amylovora and designated tn5393a and tn5393b, respectively. the putative recombination site (res) and resolvase-repressor (tnpr) genes of tn5393 from e. amylovora, p syringae, and x. campestris were identical; however, is6100 ... | 1995 | 7487022 |
| [heterogeneity of lipopolysaccharides isolated from the cell membrane of pseudomonas syringae 8414]. | | 1980 | 7402101 |
| structural studies of the side chain of outer membrane lipopolysaccharide from pseudomonas syringae pv. coriandricola w-43. | the lipopolysaccharide (lps) was isolated from pseudomonas syringae pv. coriandricola w-43 by hot phenol-water extraction. rhamnose and 3-n-acetyl-3-deoxyfucose were found to be the major sugar constituents of the lps together with n-acetylglucosamine, n-acetylgalactosamine, heptose, and 3-deoxy-d-manno-octulosonic acid (kdo). the main fatty acids of lipid a of the lps were 3-oh-c:10, c12:0, 2-oh-c12:0, and 3-oh-c12:0. the o-specific polysaccharide liberated from the lps by mild-acid hydrolysis ... | 1994 | 7525536 |
| development of a microbial community of bacterial and yeast antagonists to control wound-invading postharvest pathogens of fruits. | two antagonists, the bacterium pseudomonas syringae and the pink yeast sporobolomyces roseus, against blue mold (caused by penicillium expansum) on apple controlled this disease more effectively when combined at approximately equal biomass (50:50 of the same turbidity) than in individual applications. addition of l-asparagine enhanced the biocontrol effectiveness of p. syringae but decreased that of s. roseus and had no significant effect when the antagonists were combined. populations of both a ... | 1995 | 7574636 |
| product of fosc, a gene from pseudomonas syringae, mediates fosfomycin resistance by using atp as cosubstrate. | pseudomonas syringe pb-5123, a producer of fosfomycin, is resistant to high concentrations of the antibiotic. two possible mechanisms of resistance have been detected: (i) impermeability to exogenous fosfomycin, even in the presence of sugar phosphate uptake inducers, and (ii) antibiotic phosphorylation. the gene responsible for this last activity, fosc, encodes a ca. 19,000-da protein and is immediately followed by a second open reading frame, which shows sequence similarities to glutathione s- ... | 1995 | 7492106 |
| role of the phytotoxin coronatine in the infection of arabidopsis thaliana by pseudomonas syringae pv. tomato. | the role of the phytotoxin coronatine in the virulence of pseudomonas syringae pv. tomato in arabidopsis thaliana was evaluated by comparing symptom development, in planta bacterial multiplication, and the induction of defense-related genes in arabidopsis plants inoculated with the coronatine-producing (cor+) p. s. pv. tomato strain dc3000 and the coronatine-defective (cor-) strain dc3661 by either infiltration or dipping methods. the cor+ strain, p. s. pv. tomato dc3000, caused severe disease s ... | 1995 | 7539639 |
| the complete hrp gene cluster of pseudomonas syringae pv. syringae 61 includes two blocks of genes required for harpinpss secretion that are arranged colinearly with yersinia ysc homologs. | pseudomonas syringae pv. syringae 61 contains a 25-kb hrp cluster that is sufficient to elicit the hypersensitive response (hr) in nonhost plants. previous studies have shown that mutations in complementation groups viii, ix, and xi in the hrp cluster abolished the ability of the bacterium to cause the hr. the sequence of a 3.7-kb smai-ssti fragment covering groups viii and ix now reveals five open reading frames (orfs) in the same transcript, designated as hrpu, hrpw, hrpo, hrpx, and hrpy, and ... | 1995 | 7579617 |
| synthetic antimicrobial peptide design. | to guide the design of potential plant pathogen-resistance genes, synthetic variants of naturally occurring antimicrobial gene products were evaluated. five 20-amino acid (esf1, esf4, esf5, esf6, esf13), one 18-amino acid (esf12), and one 17-amino acid (esf17) amphipathic peptide sequences were designed, synthesized, and tested with in vitro bioassays. positive charges on the hydrophilic side of the peptide were shown to be essential for antifungal activity, yet the number of positive charges co ... | 1995 | 7579625 |
| intergeneric transfer and functional expression of the tomato disease resistance gene pto. | plant disease resistance loci have been used successfully in breeding programs to transfer traits from resistant germplasm to susceptible plant cultivars. the molecular cloning of plant disease resistance genes now permits the transfer of such traits across species boundaries by genetic transformation of recipient hosts. the tomato disease resistance gene pto confers resistance to strains of the bacterial pathogen pseudomonas syringae pv tomato expressing the avirulence gene avrpto. transformati ... | 1995 | 7580250 |
| high frequency of conjugation versus plasmid segregation of rp1 in epiphytic pseudomonas syringae populations. | the maintenance and transfer of the broad host-range plasmid rp1 in epiphytically growing populations of pseudomonas syringae was monitored in the phyllosphere of bush bean (phaseolus vulgaris). when foliage was inoculated with plasmid-containing bacteria, the plasmid was lost from the majority of the cells within 2 d but was stably maintained in 0.8% of the population. a high frequency of conjugation between added donors and recipients was observed under high humidity conditions. in 1 d, the nu ... | 1995 | 7582033 |
| survival, transmission, and taxonomy of pseudomonas syringae van hall, the causal organism of bacterial brown spot of bean (phaseolus vulgaris l.). | | 1968 | 5646844 |
| a modified two-component regulatory system is involved in temperature-dependent biosynthesis of the pseudomonas syringae phytotoxin coronatine. | biosynthesis of the phytotoxin coronatine (cor) in pseudomonas syringae pv. glycinea pg4180 is regulated by temperature at the transcriptional level. a 3.4-kb dna fragment from the cor biosynthetic gene cluster restored temperature-regulated phytotoxin production to tn5 mutants defective in cor production. nucleotide sequence analysis of this fragment revealed three genes, cors, corp, and corr, which encode a modified two-component regulatory system consisting of one sensor protein, cors, and tw ... | 1995 | 7592381 |
| hrpl activates erwinia amylovora hrp gene transcription and is a member of the ecf subfamily of sigma factors. | hrpl of erwinia amylovora ea321 encodes a 21.7-kda regulatory protein, similar to members of the ecf (extra cytoplasmic functions) subfamily of eubacterial rna polymerase sigma factors. hrpl is a single-gene operon in complementation group vi of the e. amylovora hrp gene cluster. its product is required by ea321 to elicit the hypersensitive response (hr) and to cause disease. hrpl controls the expression of five independent hrp loci, including hrpn, which encodes harpin, a proteinaceous elicitor ... | 1995 | 7592386 |
| cloning of genes required for hypersensitivity and pathogenicity in pseudomonas syringae pv. aptata. | a genomic library of pseudomonas syringae pv. aptata strain ncppb 2664, which causes bacterial blight of sugar beet, lettuce and other plants, was constructed in the cosmid vector pcpp31. the 13.4 kb ecori fragment of the cosmid phir11, containing the hrp (hypersensitive response and pathogenicity) gene cluster of the closely related bacterium pseudomonas syringae pv. syringae strain 61, was used as a probe to identify a homologous hrp gene cluster in p. syringae pv. aptata. thirty of 2500 cosmi ... | 1995 | 7771767 |
| a global regulator of secondary metabolite production in pseudomonas fluorescens pf-5. | mutations in the apda (for antibiotic production) gene of the plant root-colonizing bacterium pseudomonas fluorescens pf-5 pleiotropically abolish the production of an array of antibiotics, including pyrrolnitrin, pyoluteorin, and 2,4-diacetylphloroglucinol, as well as the production of tryptophan side chain oxidase, hydrogen cyanide, and an extracellular protease. the lack of production of secondary metabolites by apda- mutants was correlated with the loss of inhibition of the phytopathogenic f ... | 1995 | 7592389 |
| cloning and characterization of the katb gene of pseudomonas aeruginosa encoding a hydrogen peroxide-inducible catalase: purification of katb, cellular localization, and demonstration that it is essential for optimal resistance to hydrogen peroxide. | pseudomonas aeruginosa is an obligate aerobe that is virtually ubiquitous in the environment. during aerobic respiration, the metabolism of dioxygen can lead to the production of reactive oxygen intermediates, one of which includes hydrogen peroxide. to counteract the potentially toxic effects of this compound, p. aeruginosa possesses two heme-containing catalases which detoxify hydrogen peroxide. in this study, we have cloned katb, encoding one catalase gene of p. aeruginosa. the gene was clone ... | 1995 | 7592431 |
| molecular characterization of the pseudomonas syringae pv. pisi plasmid-borne avirulence gene avrppib which matches the r3 resistance locus in pea. | an avirulence gene (designated avrppib) from race 3 of pseudomonas syringae pv. pisi was cloned and sequenced. the gene corresponded to a single open reading frame of 831 nt identified by transposon mutagenesis and subcloning. this orf encodes a predicted hydrophilic protein of 276 amino acids (mw 31,300). it effects the expression of a resistance mechanism governed by a single genetic locus in pea. cosegregation of resistance at the r3 locus of pea was observed towards race 3 and a transconjuga ... | 1995 | 7579614 |
| antibacterial polyphenols from olive oil mill waste waters. | olive oil vegetation waters (vw) were highly toxic to both phytopathogenic pseudomonas syringae (smith, yung et al.) pv. savastanoi (gram-negative) and corynebacterium michiganense (gram-positive) and showed bactericidal activity in their original concentration (in raw form). among the main polyphenols, present in the waste waters, methylcatechol proved to be the most toxic to ps. savastanoi at 10(-4) mol l-1, and also demonstrated bactericidal activity, while on coryne. michiganense it was only ... | 1995 | 7592132 |
| the arabidopsis thaliana 4-coumarate:coa ligase (4cl) gene: stress and developmentally regulated expression and nucleotide sequence of its cdna. | an arabidopsis cdna clone encoding 4-coumarate:coa ligase (4cl), a key enzyme of phenylpropanoid metabolism, was identified and sequenced. the predicted amino acid sequence is similar to those of other cloned 4cl genes. southern blot analysis indicated that 4cl is single-copy gene in arabidopsis. northern blots showed that 4cl expression was activated early during seedling development. the onset of 4cl expression was correlated with the onset of lignin deposition in cotyledons and roots 2-3 days ... | 1995 | 7640359 |
| the avrrpm1 gene of pseudomonas syringae pv. maculicola is required for virulence on arabidopsis. | we demonstrate that the avirulence gene avrrpm1, isolated from pseudomonas syringae pv. maculicola strain psm m2 via interaction with the arabidopsis resistance gene rpm1, is also required for maximal virulence on this host. two avrrpm1::tn3-spice marker-exchange mutants do not elicit a hypersensitive reaction on rpm1-containing arabidopsis accessions col-0 and oy-0. surprisingly, these mutants neither generate disease symptoms, nor grow in planta, after inoculation onto susceptible accessions n ... | 1995 | 7655064 |
| [the genetic aspects of the study of pseudomonas syringae bacteria]. | the work is a review of the state-of-art of molecular-genetic examination of bacteria p. syringae. the questions concerning new approaches to the study of determinants of pathogenicity, endogenic plasmids, toxins, resistance to antibiotics, avirulence, genes and insertion sequence elements of p. syringae are stated. | 1995 | 7655660 |
| pseudomonas syringae pv. syringae phytotoxins reversibly inhibit the plasma membrane h(+)-atpase and disrupt unilamellar liposomes. | the pseudomonas syringae pv. syringae phytotoxins syringomycin-e and syringopeptins 22-a and 25-a reversibly and noncompetitively inhibit purified h(+)-atpase solubilized from plasma membrane of maize roots. moreover, they increase the passive permeability to protons in phosphatidylcholine/phosphatidylethanolamine liposomes. both effects are more pronounced with syringopeptins than with syringomycin-e. activity on phospholipid bilayers is detectable at phytotoxin concentrations not affecting h(+ ... | 1995 | 7669032 |
| structural analysis of new syringopeptins by tandem mass spectrometry. | new syringopeptins sp(sc)-1 and -2 were isolated from culture filtrates of phytopathogenic bacterium strain sc1 of pseudomonas syringae pv. syringae. these syringopeptins were composed of a beta-hydroxy fatty acid, a long sequence of aliphatic amino acids. and a lactone moiety of eight amino acids. the amino acid sequences were deduced from a comparison of their tandem mass sepctra with those of known syringopeptins sp-22a and sp-25a. sp(sc)-1 and sp(sc)-2 resembled sp-22a, but differed from the ... | 1995 | 7670202 |
| the hrpz proteins of pseudomonas syringae pvs. syringae, glycinea, and tomato are encoded by an operon containing yersinia ysc homologs and elicit the hypersensitive response in tomato but not soybean. | the pseudomonas syringae pathovars are composed of host-specific plant pathogens that characteristically elicit the defense-associated hypersensitive response (hr) in nonhost plants. p. s. pv. syringae 61 secretes an hr elicitor, harpinpss (hrpzpss), in a hrp-dependent manner. an internal fragment of the p. s. pv. syringae 61 hrpz gene was used to clone the hrpz locus from p. s. pv. glycinea race 4 (bacterial blight of soybean) and p. s. pv. tomato dc3000 (bacterial speck of tomato). dna sequenc ... | 1995 | 7579616 |
| structure of the arabidopsis rpm1 gene enabling dual specificity disease resistance. | plants can recognize pathogens through the action of disease resistance (r) genes, which confer resistance to pathogens expressing unique corresponding avirulence (avr) genes. the molecular basis of this gene-for-gene specificity is unknown. the arabidopsis thaliana rpm1 gene enables dual specificity to pathogens expressing either of two unrelated pseudomonas syringae avr genes. despite this function, rpm1 encodes a protein sharing molecular features with recently described single-specificity r ... | 1995 | 7638602 |
| cloning, characterization and phenotypic expression in escherichia coli of catf, which encodes the catalytic subunit of catalase isozyme catf of pseudomonas syringae. | the phytophathogenic, gram-negative bacterium pseudomonas syringae pv. syringae 61 contains three isozymes of catalase (ec 1.11.1.6), which have been proposed to play a role in the bacterium's responses to various environmental stresses. to study the role of individual isozymes, the gene coding for the catalytic subunit of one catalase isozyme was cloned from a cosmid library hosted in escherichia coli dh5 alpha by using a designed catalase-specific dna probe for the screening. one out of four c ... | 1995 | 7546603 |
| analysis of the syrb and syrc genes of pseudomonas syringae pv. syringae indicates that syringomycin is synthesized by a thiotemplate mechanism. | the syrb and syrc genes are required for synthesis of syringomycin, a lipodepsipeptide phytotoxin produced by pseudomonas syringae pv. syringae, and are induced by plant-derived signal molecules. a 4,842-bp chromosomal region containing the syrb and syrc genes of strain b301d was sequenced and characterized. the open reading frame (orf) of syrb was 2,847 bp in length and was predicted to encode an approximately 105-kda protein, syrb, with 949 amino acids. searches of databases revealed that syrb ... | 1995 | 7608074 |
| hydrogen peroxide does not function downstream of salicylic acid in the induction of pr protein expression. | the roles of salicylic acid (sa) and h2o2 in the induction of pr proteins in tobacco have been examined. studies were conducted on wild-type tobacco and plants engineered to express a bacterial salicylate hydroxylase capable of metabolizing sa to catechol (sh-l plants). wild-type and pr-1a-gus-transformed plants express pr-1a following challenge with pseudomonas syringae pathovar syringae, sa or 2,6-dichloro-isonicotinic acid (ina). in contrast, sh-l plants failed to respond to sa but did expres ... | 1995 | 7670505 |
| purification and characterization of an extracellular levansucrase from pseudomonas syringae pv. phaseolicola. | levansucrase (ec 2.4.1.10), an exoenzyme of pseudomonas syringae pv. phaseolicola, was purified to homogeneity from the cell supernatant by chromatography on tmae-fraktogel and butyl-fraktogel. the enzyme has molecular masses of 45 kda under denaturing conditions and 68 kda during gel filtration of the native form. in isoelectric focusing, active bands appeared at ph 3.55 and 3.6. maximum sucrose cleaving activities were measured at ph 5.8 to 6.6 and 60 degrees c. the enzyme was highly tolerant ... | 1995 | 7751294 |
| dna sequence and transcriptional analysis of the tbla gene required for tabtoxin biosynthesis by pseudomonas syringae. | the tbla gene of pseudomonas syringae is required for tabtoxin biosynthesis and is under the control of a regulatory gene, lema. we have determined the nucleotide sequence of the tbla gene and identified the 5' end of the tbla gene transcript. the sequence of the tbla gene was identified to that of the recently reported open reading frame 1 gene of the taba region of the br2 chromosome. the open reading frame of the tbla gene potentially encodes a protein of 231 amino acids. mrna from the tbla g ... | 1993 | 7679566 |
| saprophytic pseudomonas syringae strain m1 of wheat produces cyclic lipodepsipeptides. | a saprophytic fluorescent bacterium (strain m1) isolated from wheat was identified as pseudomonas syringae and shown to produce the cyclic lipodepsipeptides, syringomycin e and syringopeptin sp25a. m1 grew in planta but did not affect germination or cause disease symptoms in wheat. the findings show that the production of these metabolites, generally regarded as plant virulence factors, does not correlate with plant pathogenicity. | 1995 | 7557311 |
| differential effects of growth temperature on ice nuclei active at different temperatures that are produced by cells of pseudomonas syringae. | the temperature at which ice-nucleating bacteria are grown causes differences of 100- to 10,000-fold in the fraction of cells that nucleate ice at a given temperature (ice nucleation frequency). ice nucleation frequencies of cells of pseudomonas syringae grown at temperatures that ranged from 9 to 33 degrees c were examined in order to more accurately characterize physiological effects on ice nuclei active at temperatures of from about -2 to -10 degrees c, the temperature range for this phenotyp ... | 1995 | 7743815 |
| use of charge-coupled device (ccd) image-enhancement for rapid screening and monitoring of prokaryotic promoter expression. | charge-coupled device (ccd) image-enhancement was used for rapid screening of genomic libraries and allowed selection of promoters with differing characteristics. in addition, both the ccd and luminometry were used to monitor and characterize the expression from two pseudomonas syringae pv. phaseolicola promoters. the same pattern of gene expression was indicated by the two methods but the ccd enabled the rapid non-destructive in situ monitoring of a microbial population, over a prolonged period ... | 1993 | 7763449 |
| cloning and sequencing of an ice nucleation active gene of erwinia uredovora. | an ice nucleation activity gene, named inau, of the bacterium erwinia uredovora kuin-3 has been sequenced. this gene encodes a protein of 1034 amino acid residues, and its expression product, inau protein, has an 832-amino acid residue segment consisting of 52 repeats of closely related 16-amino acid motifs (r-domain), flanked by n- and c-terminal sequences (n- and c-domains, respectively). the primary structure of the inau protein is similar to those of the inaa, inaw, and inaz gene products of ... | 1994 | 7764866 |
| ccd-monitoring of bioluminescence during the induction of the cell wall-deficient, l-form state of a genetically modified strain of pseudomonas syringae pv. phaseolicola. | bioluminescence from developing l-form colonies of the plant pathogen, pseudomonas syringae pv. phaseolicola, was monitored using the enhanced light-detecting capabilities of a charge-coupled device. during l-form induction, the bacteria entered a prolonged period during which the level of light output and hence metabolic activity, was very low. a relatively small number of highly bioluminescent l-form colonies were then observed to develop against a background of non-bioluminescent bacteria. wh ... | 1994 | 7765223 |
| resistance to antifungal agents. | the marked increase in the number of patients with aids and other forms of immunocompromise has resulted in the emergence of fungi as predominant pathogens in many institutions. unfortunately, with the widespread use of antifungal agents to combat these infections, reports of resistance to antifungal agents have proliferated. in the present environment, the occurrence of resistance to antifungal agents is neither rare nor of negligible clinical importance. the expanding demand for antifungal age ... | 1995 | 7761146 |
| characterization of avre from pseudomonas syringae pv. tomato: a hrp-linked avirulence locus consisting of at least two transcriptional units. | cosmid clone ppt10e9 from pseudomonas syringae pv. tomato caused p. s pv. glycinea to elicit the hr on leaves of all tested soybean cultivars. the avirulence function of ppt10e9, called avre, occurred on an 11.3-kb dna fragment located immediately adjacent to the p. s. pv. tomato hrp gene cluster. tn3-gus saturation mutagenesis of the avre locus and adjacent dna revealed at least four transcriptional units occurring immediately adjacent to the hrprs locus that were all regulated in a manner simi ... | 1995 | 7772803 |
| the hrprs locus of pseudomonas syringae pv. phaseolicola constitutes a complex regulatory unit. | the right part of the hrp cluster of pseudomonas syringae pv. phaseolicola contains two regulatory genes, the previously described hrps gene and an adjacent locus, hrpr. in this study we determined the sequence of hrpr and analysed the functional organization of the two genes. hrpr and hrps show high sequence similarities to each other and to other response regulators of the two-component regulatory system. this has recently also been described for the hrprs system of the closely related pathoge ... | 1995 | 7752891 |
| use of arabidopsis thaliana defense-related mutants to dissect the plant response to pathogens. | the plant defense response to microbial pathogens had been studied primarily by using biochemical and physiological techniques. recently, several laboratories have developed a variety of pathosystems utilizing arabidopsis thaliana as a model host so that genetic analysis could also be used to study plant defense responses. utilizing a pathosystem that involves the infection of arabidopsis with pathogenic pseudomonads, we have cloned the arabidopsis disease-resistance gene rps2, which corresponds ... | 1995 | 7753782 |
| genetic and plasmid diversity within natural populations of pseudomonas syringae with various exposures to copper and streptomycin bactericides. | we examined the genetic and plasmid diversity within natural populations of pseudomonas syringae isolated from three ornamental pear nurseries in eastern oklahoma. the bactericide spray regimen differed at each nursery; copper and streptomycin, only copper, and no bactericides were applied at nurseries i, ii, and iii respectively. resistance to copper (cur) and resistance to streptomycin (smr) were determined for 1,938 isolates of p. syringae; isolates from nurseries i and ii were generally cur ... | 1994 | 7811082 |
| membrane fluidity as a factor in production and stability of bacterial ice nuclei active at high subfreezing temperatures. | detailed measurements were made of the rate of appearance of bacterial ice nuclei upon cooling of suspensions of pseudomonas syringae cells and the disappearance of ice nuclei upon warming of the cells before assay for ice nucleation activity. while no substantial change in numbers of ice nuclei active at either -5 or at -9 degrees c was observed in cells that were grown at temperatures lower than 24 degrees c and cooled to 21 degrees c before assay, large increases in -5 but not -9 degrees c ic ... | 1995 | 7781327 |
| a member of the tomato pto gene family confers sensitivity to fenthion resulting in rapid cell death. | leaves of tomato cultivars that contain the pto bacterial resistance locus develop small necrotic lesions within 24 hr after exposure to fenthion, an organophosphorous insecticide. recently, the pto gene was isolated and shown to be a putative serine/threonine protein kinase. pto is one member of a multigene family that is clustered within a 400-kb region on chromosome 5. here, we report that another member of this gene family, termed fen, is responsible for the sensitivity to fenthion. fen was ... | 1994 | 7827490 |
| copper as a signal for alginate synthesis in pseudomonas syringae pv. syringae. | plant-associated pseudomonads are commonly exposed to copper bactericides, which are applied to reduce the disease incidence caused by these bacteria. consequently, many of these bacteria have acquired resistance or tolerance to copper salts. we recently conducted a survey of 37 copper-resistant (cur) pseudomonas spp., including p. cepacia, p. fluorescens, p. syringae, and p. viridiflava, and found that a subset of the p. syringae strains showed a dramatic increase in exopolysaccharide (eps) pro ... | 1995 | 7793938 |
| extensin gene expression is induced by mechanical stimuli leading to local cell wall strengthening in nicotiana plumbaginifolia. | nicotiana plumbaginifolia viv. harbors a single extensin gene, although related hydroxyproline-rich sequences are present in the genome. northern analysis showed that the gene is highly expressed in roots and to a lesser extent in stems. expression in leaves is low but mrna levels are increased upon infection with the incompatible bacterium pseudomonas syringae. extensin transcript levels in leaves were slightly enhanced after wounding and salicylic acid treatment. in-situ hybridization experime ... | 1994 | 7765795 |
| newer systems for bacterial resistances to toxic heavy metals. | bacterial plasmids contain specific genes for resistances to toxic heavy metal ions including ag+, aso2-, aso4(3-), cd2+, co2+, cro4(2-), cu2+, hg2+, ni2+, pb2+, sb3+, and zn2+. recent progress with plasmid copper-resistance systems in escherichia coli and pseudomonas syringae show a system of four gene products, an inner membrane protein (pcod), an outer membrane protein (pcob), and two periplasmic cu(2+)-binding proteins (pcoa and pcoc). synthesis of this system is governed by two regulatory p ... | 1994 | 7843081 |
| evaluation of determinative tests for pathovars of pseudomonas syringae van hall 1902. | the utility of 36 presumptive determinative tests for 32 pathovars of pseudomonas syringae was investigated. a total of 395 strains was examined. most strains of 12 of these pathovars (ps. syringae pv. cannabina, ps. syr. delphinii, ps. syr. glycinea, ps. syr. helianthi, ps. syr. lachrymans, ps. syr. mori, ps. syr. morsprunorum, ps. syr. phaseolicola, ps. syr. 'porri', ps. syr. papulans, ps. syr. savastanoi and ps. syr. tabaci) formed clusters when test data were compared by centroid analysis. p ... | 1994 | 7961191 |
| phosphorylation of membrane proteins in response to temperature in an antarctic pseudomonas syringae. | temperature-dependent phosphorylation and dephosphorylation of membrane proteins was studied in vitro in a number of psychrotrophic antarctic bacteria which grow between 0 and 30 degrees c. one of them, a pseudomonas syringae isolate, was studied in detail and was found to have three membrane proteins of molecular mass 30, 65 and 85 kda which were phosphorylated differently in response to low and high temperatures. the 65 kda protein was phosphorylated only at lower temperatures (between 0 and 1 ... | 1994 | 7881543 |
| erwinia chrysanthemi and pseudomonas syringae: plant pathogens trafficking in extracellular virulence proteins. | | 1994 | 7859513 |
| a disease resistance gene in arabidopsis with specificity for two different pathogen avirulence genes. | the rps3 and rpm1 disease resistance loci of arabidopsis confer resistance to pseudomonas syringae strains that carry the avirulence genes avrb and avrrpm1, respectively. we have previously shown that rps3 and rpm1 are closely linked genetically. here, we show that rps3 and rpm1 are in fact the same gene. we screened a mutagenized arabidopsis population with a p. syringae strain carrying avrb and found 12 susceptible mutants. all 12 mutants were also susceptible to an isogenic strain carrying av ... | 1994 | 8069104 |
| a mutation in arabidopsis that leads to constitutive expression of systemic acquired resistance. | systemic acquired resistance (sar) is a nonspecific defense response in plants that is associated with an increase in the endogenous level of salicylic acid (sa) and elevated expression of pathogenesis-related (pr) genes. to identify mutants involved in the regulation of pr genes and the onset of sar, we transformed arabidopsis with a reporter gene containing the promoter of a beta-1,3-glucanase-encoding pr gene (bgl2) and the coding region of beta-glucuronidase (gus). the resulting transgenic l ... | 1994 | 7866028 |
| effect on lipopolysaccharide structure of aeration during growth of a plum isolate of pseudomonas syringae pv. morsprunorum. | the composition of lipopolysaccharide (lps) extracted with aqueous phenol from a virulent english plum isolate of pseudomonas syringae pv. morsprunorum varied according to the partial pressure of oxygen (po2) in the culture medium at the time of harvest. when po2 was low, the organism grew slowly and produced smooth lps bearing rhamnan sidechains. as po2 was raised, the rate of growth increased and smooth lps was replaced by a rough species deficient in rhamnose, which co-extracted with a d-gluc ... | 1994 | 8075800 |
| characterization of avrpphe, a gene for cultivar-specific avirulence from pseudomonas syringae pv. phaseolicola which is physically linked to hrpy, a new hrp gene identified in the halo-blight bacterium. | the avirulence gene matching the r2 gene for resistance to halo-blight disease in phaseolus was cloned and sequenced from race 4 strain 1302a of pseudomonas syringae pv. phaseolicola. the predicted 41-kda avrpphe protein is hydrophilic, has no features that indicate function, and no similarity to other protein sequences. the promoter region of avrpphe contains a "harp box" motif. the gene was expressed more strongly in minimal than in nutrient-rich media. lower concentrations of the phytoalexin ... | 1994 | 7873779 |
| use of a gene expression system based on potato virus x to rapidly identify and characterize a tomato pto homolog that controls fenthion sensitivity. | a novel transient gene expression system was used to study both the tomato disease resistance gene pto and a pto homolog designated fen. the gene expression system was based on potato virus x (pvx). tomato plants that were both susceptible to strains of pseudomonas syringae pv tomato carrying the corresponding avirulence gene avrpto and insensitive to the insecticide fenthion were infected with in vitro-generated transcripts of pvx derivatives containing either pto or fen. expression of the pto ... | 1995 | 7734960 |
| isolation and sequence analysis of the pseudomonas syringae pv. tomato gene encoding a 2,3-diphosphoglycerate-independent phosphoglyceromutase. | pseudomonas syringae pv. tomato dc3481, a tn5-induced mutant of the tomato pathogen dc3000, cannot grow and elicit disease symptoms on tomato seedlings. it also cannot grow on minimal medium containing malate, citrate, or succinate, three of the major organic acids found in tomatoes. we report here that this mutant also cannot use, as a sole carbon and/or energy source, a wide variety of hexoses and intermediates of hexose catabolism. uptake studies have shown that dc3481 is not deficient in tra ... | 1995 | 7896694 |
| sequence, expression and transcriptional analysis of the coronafacate ligase-encoding gene required for coronatine biosynthesis by pseudomonas syringae. | pseudomonas syringae pv. glycinea pg4180 produces the chlorosis-inducing phytotoxin coronatine (cor), which consists of a polyketide component, coronafacic acid (cfa), ligated by an amide bond to coronamic acid (cma), an ethylcyclopropyl amino-acid derived from isoleucine. we report the nucleotide sequence of a 2.37-kb region containing the coronafacate ligase-encoding gene (cfl) which is required for the amide linkage of cfa and cma. the transcription start point for cfl was identified, and the ... | 1995 | 7883180 |
| tomato mutants altered in bacterial disease resistance provide evidence for a new locus controlling pathogen recognition. | we have employed a genetic approach to study the resistance of tomato to the phytopathogenic bacterium pseudomonas syringae pv tomato. resistance to p. s. tomato depends upon expression of the pto locus in tomato, which encodes a protein with similarity to serine/threonine protein kinases and recognizes pathogen strains expressing the avirulence gene avrpto. eleven tomato mutants were isolated with altered resistance to p. s. tomato strains expressing avrpto. we identified mutations both in the ... | 1994 | 7911348 |
| restriction fragment length polymorphism evidence for genetic homology within a pathovar of pseudomonas syringae. | pseudomonas syringae pv. phaseolicola nps3121 hrp sequences were used as hybridization probes in a restriction fragment length polymorphism (rflp) analysis of 24 p. syringae pv. tabaci strains as a means to evaluate the genetic and taxonomic relationship of pathovars of p. syringae. southern blot analyses of genomic restriction digests, with hrpa-s sequences as hybridization probes, and restriction analyses of pcr-amplified dna of regions within hrpd were conducted. the resulting rflp patterns w ... | 1994 | 7912500 |
| identification and relatedness of coronatine-producing pseudomonas syringae pathovars by pcr analysis and sequence determination of the amplification products. | production of the chlorosis-inducing phytotoxin coronatine in the pseudomonas syringae pathovars atropurpurea, glycinea, maculicola, morsprunorum, and tomato has been previously reported. dna hybridization studies previously indicated that the coronatine biosynthetic gene cluster is highly conserved among p. syringae strains which produce the toxin. in the present study, two 17-bp oligonucleotide primers derived from the coronatine biosynthetic gene cluster of p. syringae pv. glycinea pg4180 wer ... | 1994 | 7916181 |
| molecular mechanisms of copper resistance and accumulation in bacteria. | an unusual mechanism of metal resistance is found in certain plant pathogenic strains of pseudomonas syringae that are exposed to high levels of copper compounds used in disease control on agricultural crops. these bacteria accumulate blue cu2+ ions in the periplasm and outer membrane. at least part of this copper sequestering activity is determined by copper-binding protein products of the copper resistance operon (cop). potential copper-binding sites of the periplasmic copa protein show conser ... | 1994 | 7917425 |
| syringomycin production among strains of pseudomonas syringae pv. syringae: conservation of the syrb and syrd genes and activation of phytotoxin production by plant signal molecules. | the syrb and syrd genes of pseudomonas syringae pv. syringae are predicted to encode proteins that function in the synthesis and export of syringomycin, respectively. using portions of the syr genes as dna probes, both genes were shown to be conserved as single copies within a 15-kb or smaller dna region among a broad spectrum of p. s. pv. syringae strains that produce syringomycin or one of its amino acid analogs, syringotoxin and syringostatin. strains representative of p. viridiflava and six ... | 1994 | 7909458 |
| the cloning and characterization of phage promoters, directing high expression of luciferase in pseudomonas syringae pv. phaseolicola, allowing single cell and microcolony detection. | regions of dna containing promoter sequences from a pseudomonas syringae pv. phaseolicola-specific phage (phi 11p) were identified by shotgun cloning into a broad-host-range promoter-probe vector (pqf70). when used in conjunction with the luciferase reporter genes, one of these dna fragments, 19h, directed gene expression at a level which enabled the subsequent light output (bioluminescence) of single cells of p. syringae pv. phaseolicola to be detected and visualized using a charge-coupled devi ... | 1993 | 8162227 |
| two native plasmids of pseudomonas syringae pathovar tomato strain pt23 share a large amount of repeated dna, including replication sequences. | strain pt23 of pseudomonas syringae pv. tomato contains four native plasmids, designated a, b, c, and d. by dna hybridization of genomic and plasmid dna digests from the wild type and a plasmid-cured strain, we determined that c. 61 kb (c. 74%) of ppt23b is repeated in ppt23 a and only c. 17 kb (c. 21%) is in single copy in strain pt23. ppt23b also contains dna repeated in the chromosome that occurs in three dna fragments of 0.6, 4.6, and 9.6 kb that might be transposable elements. additionally, ... | 1994 | 7934901 |
| erwinia chrysanthemi hrp genes and their involvement in soft rot pathogenesis and elicitation of the hypersensitive response. | unlike the bacterial pathogens that typically cause the hypersensitive response (hr) in plants, erwinia chrysanthemi has a wide host range, rapidly kills and macerates host tissues, and secretes several isozymes of the macerating enzyme pectate lyase (pel). pelabce- and out- (secretion-deficient) mutants were observed to produce a rapid necrosis in tobacco leaves that was indistinguishable from the hr elicited by the narrow-host-range pathogens e. amylovora ea321 and pseudomonas syringae pv. syr ... | 1994 | 7949326 |
| avirulence gene avrpphc from pseudomonas syringae pv. phaseolicola 3121: a plasmid-borne homologue of avrc closely linked to an avrd allele. | cosmid clone ppsp01 from race 1 pseudomonas syringae pv. phaseolicola isolate 3121 conferred a unique pattern of soybean cultivar reactions when expressed in p. s. pv. glycinea r4. the avirulence phenotype was shown to result from the presence in clone ppsp01 of an avrd allele as well as an additional avirulence gene located approximately 5-kb upstream. the new gene, called avrpphc, shows high identity to and is phenotypically identical to avrc, previously cloned from p. s. pv. glycinea race 0. ... | 1994 | 7949327 |
| ethylene production by strains of the plant-pathogenic bacterium pseudomonas syringae depends upon the presence of indigenous plasmids carrying homologous genes for the ethylene-forming enzyme. | the molecular characteristics of the ethylene-forming enzymes of strains of pseudomonas syringae were tested. the ethylene-producing activities of the nine strains as measured in vivo and in vitro were similar, except for that of p. syringae pv. mori m5. a polyclonal antibody and a dna probe for the ethylene-forming enzyme from p. syringae pv. phaseolicola pk2 were prepared to investigate homologies among the proteins and genes for the ethylene-forming enzymes. with the exception of p. syringae ... | 1994 | 7952184 |
| characterization of high-frequency deletions in the iaa-containing plasmid, piaa2, of pseudomonas syringae pv. savastanoi. | the phytopathogenic bacterium pseudomonas syringae pv. savastanoi causes olive and oleander knot disease. the bacterium induces the formation of tumorous galls by the synthesis and secretion of the plant hormones trans-zeatin riboside and indole-3-acetic acid into host intercellular spaces. an italian oleander isolate, pb213, has been observed to lose the ability to synthesize iaa at high frequency, thus becoming non-pathogenic. the iaa genes, located on the 72-kb iaa-containing plasmid, piaa2 w ... | 1994 | 7909615 |
| periplasmic glucans of pseudomonas syringae pv. syringae. | we report the initial characterization of glucans present in the periplasmic space of pseudomonas syringae pv. syringae (strain r32). these compounds were found to be neutral, unsubstituted, and composed solely of glucose. their size ranges from 6 to 13 glucose units/mol. linkage studies and nuclear magnetic resonance analyses demonstrated that the glucans are linked by beta-1,2 and beta-1,6 glycosidic bonds. in contrast to the periplasmic glucans found in other plant pathogenic bacteria, the gl ... | 1994 | 7961404 |