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ornithine carbamoyltransferase genes and phaseolotoxin immunity in pseudomonas syringae pv. phaseolicola.two different dna fragments encoding ornithine carbamoyltransferase (octase) were cloned from pseudomonas syringae pv. phaseolicola nps3121. these fragments did not cross-hybridize and encoded octases which differed with respect to their sensitivity to purified phaseolotoxin, an octase inhibitor produced by this phytopathogenic bacterium. recombinant plasmids carrying these dna fragments complemented octase-deficient strains of escherichia coli and pseudomonas aeruginosa. extracts of the complem ...198716453811
self-protection of pseudomonas syringae pv. "tabaci" from its toxin, tabtoxinine-beta-lactam.an extracellular toxin, tabtoxinine-beta-lactam (t beta l), is produced by pseudomonas syringae pv. "tabaci." this toxin irreversibly inhibits its target, glutamine synthetase; yet p. syringae pv. "tabaci" retains significant amounts of glutamine synthetase activity during toxin production in culture. as part of our investigation of the self-protection of p. syringae pv. "tabaci," we compared the effects of t beta l on tox+ (t beta l-producing, insensitive to t beta l) and tox- (t beta l nonprod ...19873571155
molecular cloning and biological characterization of the reca gene from pseudomonas syringae.we have identified a recombinant plasmid, pcuv8, from a cosmid library of pseudomonas syringae genomic dna which contains a functional analog of the escherichia coli reca gene. the plasmid was initially identified by its ability to restore uv resistance to e. coli hb101. quantitative analysis demonstrated that it restored both recombination proficiency and uv resistance to an e. coli reca deletion mutant. by these criteria, pcuv8 appears to contain the p. syringae reca gene. several pathogenic a ...19873584077
characterization of two ornithine carbamoyltransferases from pseudomonas syringae pv. phaseolicola, the producer of phaseolotoxin.two ornithine carbamoyltransferases (oct 1 and oct 2) were isolated from pseudomonas syringae pv. phaseolicola and purified by precipitation with ammonium sulfate, heat denaturation, chromatography on deae-sephadex a-50 and sephadex g-200. molecular weights of both enzymes: 110,000; optimal activity: ph 8.5 to 9.5 (oct 1), ph 8.4 (oct 2); apparent km for ornithine: 7 x 10(-4) (both enzymes); apparent km for carbamoyl-phosphate: 7 x 10(-4) (oct 1), 2.8 x 10(-3) (oct 2). both enzymes possess only ...19873592910
membrane fusion in prokaryotes: bacteriophage phi 6 membrane fuses with the pseudomonas syringae outer membrane.protein-triggered membrane fusion in the prokaryotic system is described using the lipid-containing enveloped bacterial virus phi 6 and its host, the gram-negative bacterium pseudomonas syringae. bacteriophage particles can be fused to form multiple particles where two or more nucleocapsids are surrounded by a single membrane vesicle with a volume proportional to the number of fused particles. for fusion to occur, a fusogenic protein is required in the membrane of the participating phage particl ...19873608985
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 ...19873624204
copper resistance in bacteria.copper is a required trace element for many organisms, yet it can exert an inhibitory effect on bacterial growth at relatively low concentrations. however, there are some bacterial species that can tolerate high levels of copper. it also has been reported that copper resistance is plasmid-encoded in escherichia coli, proteus vulgaris and a pseudomonas syringae isolate. it is not known if copper is effluxed from the cell, detoxified by binding to copper-binding proteins, or binds to cell-surface ...19873153166
effect of heat or chemical treatment on leptospiral antigens.the use of bacterins is one of the primary methods in the control of leptospirosis in domestic animals, especially cattle, swine, and dogs. bacterins have been made using chemically treated or heat-inactivated organisms. many of the initial studies indicated that the bacterins gave complete protection, whereas later reports found that some inactivation methods resulted in bacterins that protect against death but not against kidney infection and renal shedding. this raised the possibility that so ...19873818922
conservation of plasmids among plant-pathogenic pseudomonas syringae isolates of diverse origins.thirty isolates of pseudomonas syringae pv. tabaci, pv. angulata (pathogens on tobacco), pv. coronafaciens, and pv. striafaciens (pathogens on oats) were examined for plasmid dnas. the strains were obtained from plants throughout the world, some over 50 years ago. of the 22 tobacco pathogens, 16 contain predominantly one type of plasmid, the pjp27.00 type. the remaining six tobacco-specific strains do not harbor detectable plasmids. the oat pathogens contain one, two, or three plasmids. dna homo ...19873628554
[lipopolysaccharides of the s- and r-forms of pseudomonas syringae pv. phaseolica]. 19873508945
molecular cloning of copper resistance genes from pseudomonas syringae pv. tomato.a cosmid library of copper-resistant (cur) pseudomonas syringae pv. tomato pt23 plasmid dna was constructed and mobilized into the copper-sensitive recipient p. syringae pv. syringae ps61. one resultant cosmid clone, pcop1 (46 kilobases), conferred copper resistance. the pt23 cur gene(s) was located on pcop1 by subcloning psti restriction endonuclease fragments of pcop1 in the broad-host-range vector prk404. a subclone containing a 4.4-kilobase psti fragment conferred cur on ps61. the cur gene(s ...19873027030
molecular characterization and nucleic acid sequence of an avirulence gene from race 6 of pseudomonas syringae pv. glycinea.a gene was previously cloned from pseudomonas syringae pv. glycinea race 6, designated avirulence gene a (avra), that controls the expression of virulence by the pathogen on specific cultivars of soybean. a 3.2-kilobase (kb) acci subclone from the cosmid clone ppg6l3 was shown to be active when cloned into the broad-host-range vector prk404. transposon tn5 mutagenesis and deletion analysis delineated a span of approximately 2.5 kb of dna that was necessary for gene activity. the nucleotide seque ...19873027035
outer membrane protein mediating iron uptake via pyoverdinpss, the fluorescent siderophore produced by pseudomonas syringae pv. syringae.in an iron-limited environment pseudomonas syringae pv. syringae b301d produces a yellow-green fluorescent siderophore called pyoverdinpss which functions in high-affinity iron transport. two-dimensional electrophoretic comparisons of the outer membrane proteins of strain b301d identified nine proteins which were expressed at low (50 nm) but not at high (10 microm) iron concentrations. except for the minor protein 8e, the iron-regulated proteins exhibited high molecular weights ranging from appr ...19873032911
identification and mapping of regions that confer plasmid functions and of sites for excisive recombination of plasmid pmmc7105.strain pp808 of pseudomonas syringae pv. phaseolicola contains pexc8080 (34.6 kb), the smallest of several plasmids that originated by partial excision of the cryptic plasmid, pmmc7105 (150 kb), from the host chromosome. this excision plasmid is derived entirely of sequences from pmmc7105 and contains a 24 kb region referred to as common dna, which is present in each of the other excision plasmids. a six enzyme restriction endonuclease map was constructed of pexc8080. the replication region was ...19873035336
molecular characterization of cloned avirulence genes from race 0 and race 1 of pseudomonas syringae pv. glycinea.a wide-host-range cosmid cloning vector, plafr3, was constructed and used to make cosmid libraries of partially digested sau3a dna from race 0 and race 1 of pseudomonas syringae pv. glycinea. two avirulence genes, avrb0 and avrc, cloned from race 0, elicited the hypersensitivity reaction (hr) on specific cultivars of soybean. race 4 transconjugants containing avrb0 induced a dark brown necrotic hr within 24 h on the soybean cultivars harosoy and norchief, whereas race 4 transconjugants containin ...19872824447
hemagglutinating activity in phytopathogenic bacteria surface compounds.extracellular components of plant pathogenic bacteria were obtained from their culture medium as well as from the whole cells by using nacl 1 m, ph 6.0; 20% sucrose dissolved in 0.03 m tris buffer, ph 8.0; or 0.05 m na2edta. all the extracts from erwinia carotovora subsp. carotovora, xanthomonas campestris pv. campestris, pseudomonas syringae pv. phaseolicola, xanthomonas campestris pv. phaseoli, pseudomonas solanacearum, and erwinia carotovora subsp. atroseptica, were assayed for hemagglutinati ...19873625474
[demonstration of an nad-dependent 6-phosphogluconate dehydrogenase in pseudomonas syringae pv. phaseolicola].crude extracts from cells of pseudomonas syringae pv. phaseolicola, a fluorescent pseudomonad, when grown on glucose contain a nad-linked 6-phosphogluconate dehydrogenase. the reaction of the enzyme, which produces 14co2 from 1-14c-6-phosphogluconate, is not inhibited by naf, a potent inhibitor of the enter-doudoroff (ed) pathway enzyme 6-phosphogluconate dehydratase. in the presence of phosphate or arsenate ions the nad-linked glyceraldehyde-3-phosphate dehydrogenase reacts with glyceraldehyde- ...19873625476
mucoid strains of pseudomonas aeruginosa are devoid of mannuronan c-5 epimerase.mucoid strains of azotobacter vinelandii, pseudomonas aeruginosa and pseudomonas syringae var glycinia synthesize alginate, an extracellular copolymer comprising d-mannuronosyl and l-guluronosyl moieties. extracellular mannuronan c-5 epimerase, which converts polymannuronate to alginate, was demonstrated in supernatant fluid from cultures of a. vinelandii. however, the enzyme could not be demonstrated, using the same assay, in supernatant fluids of cultures of mucoid strains of p. aeruginosa or ...19873116367
characterization of a polysaccharide component of lipopolysaccharide from pseudomonas aeruginosa iid 1008 (atcc 27584) as d-rhamnan.structural studies were carried out on a rhamnose-rich polysaccharide isolated from the o-polysaccharide fraction of lipopolysaccharide in pseudomonas aeruginosa iid 1008 (atcc 27584) after destruction of the major o-specific chain by alkaline treatment. the isolated polysaccharide contained rhamnose, 3-o-methyl-6-deoxyhexose, glucose, xylose, alanine, galactosamine and phosphorus in a molar ratio of 67:6.9:4.3:2.1:1.1:1.0:4.1. data from analysis involving smith degradation, methylation, 1h-nmr ...19873113949
inactivation of pea seed glutamine synthetase by the toxin, tabtoxinine-beta-lactam.glutamine synthetase of plants is the physiological target of tabtoxinine-beta-lactam, a toxin produced by several disease-causing pathovars of pseudomonas syringae. this toxin, a unique amino acid, is an active site-directed, irreversible inhibitor of glutamine synthetase from pea. atp is required for inactivation. neither adp, amp, nor adenosine 5'-(beta,gamma-methylene)triphosphate (amp-pcp) supports inactivation. adenyl-5'-yl imidophosphate (amp-pnp) is slowly hydrolyzed by glutamine synthet ...19872879840
the biosynthesis of tabtoxinine-beta-lactam. use of specifically 13c-labeled glucose and 13c nmr spectroscopy to identify its biosynthetic precursors.tabtoxinine-beta-lactam, an irreversible inhibitor of glutamine synthetase is produced by several pathovars of pseudomonas syringae. we have examined tabtoxinine-beta-lactam biosynthesis, an important and poorly characterized step in pathogenesis caused by this organism. we have identified the biosynthetic precursors of tabtoxinine-beta-lactam by incorporating 13c from specifically 13c-labeled d-glucose precursors and determining the labeling pattern using 13c nmr spectroscopy. tabtoxinine-beta- ...19872881927
laboratory and clinical evaluation of isolation media for campylobacter jejuni.six selective isolation media were evaluated for their ability to support the growth of campylobacter jejuni. colony counts of 70 isolated strains of c. jejuni and recovery studies on these strains in simulated positive feces samples demonstrated that bolton and hutchinson' charcoal, cefoperazone, deoxycholate agar and karmali's charcoal-based selective medium produced the highest recovery rates with the greatest suppression of other fecal flora. c. jejuni colonies were more easily recognized on ...19873429621
pea genes associated with non-host disease resistance to fusarium are also active in race-specific disease resistance to pseudomonas.a given plant species is able to resist most of the potentially pathogenic microorganisms with which it comes in contact. this phenomenon, known as non-host resistance, can be overcome only by a very small number of 'true pathogens' which can use that plant as a host. in some cases, plants have developed mechanisms for overcoming infection by specific races or strains of a true pathogen. this race-specific resistance can be easily manipulated into agronomically important cultivars by plant breed ...198724301193
composition of the microflora of witloof chicory seeds.the bacterial microflora of nine varieties of witloof chicory (cichorium intybus l. var.foliosum hegi) seeds was studied. the 184 isolates were characterized by protein profiles determined by sds-protein polyacrylamide gel electrophoresis of the total cell proteins. isolates with identical protein profiles were grouped into one fingerprint type. sixty-seven fingerprint types were distinguished. two quantitatively major fingerprint types,erwinia herbicola and an arthrobacter, represented 52% of t ...198824201719
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 ...19883372485
phospholipid requirement for expression of ice nuclei in pseudomonas syringae and in vitro.delipidation of partially purified outer membranes of pseudomonas syringae by various delipidating agents resulted in a significant loss of ice nucleation activity associated with the cell envelopes of this and other ice nucleation active bacteria. lipopolysaccharide depletion of such membranes caused no reduction in ice nucleation activity. both phospholipid content and ice nucleation activity of membranes were decreased by a similar fractional amount with time after treatment with phospholipas ...19883379073
genetic diversity and relationships of two pathovars of pseudomonas syringae.to determine genetic relationships within and between two pathovars of pseudomonas syringae, strains typical of p. syringae pv. tomato (p. s. tomato) and selected strains of p. syringae pv. syringae (p. s. syringae) were characterized by three methods. dna-dna hybridization experiments showed that strains of p. s. tomato and p. s. syringae were, respectively, 86-100% and 37-47% homologous to dna from a p. s. tomato reference strain when tested under stringent conditions. an analysis of electroph ...19882907755
isolation and characterization of pathogenicity genes of pseudomonas syringae pv. tabaci.pseudomonas syringae pv. tabaci br2 produces tabtoxin and causes wildfire disease on tobacco and bean plants. approximately 2,700 tn5 insertion mutants of a plasmid-free strain, ptbr 2.024, were generated by using suicide plasmid pgs9. of these tn5 mutants, 8 were no longer pathogenic on tobacco plants and 10 showed reduced symptoms. all of the eight nonpathogenic mutants caused typical wildfire disease symptoms on bean plants. two of the nonpathogenic mutants failed to produce tabtoxin. the eig ...19882836363
immunological characterization of ice nucleation proteins from pseudomonas syringae, pseudomonas fluorescens, and erwinia herbicola.antibodies were raised against the inaw protein, the product of the ice nucleation gene of pseudomonas fluorescens ms1650, after protein isolation from an escherichia coli clone. on western blots (immunoblots), these antibodies recognized inaw protein and inaz protein (the ice nucleation gene product of pseudomonas syringae s203), produced by both e. coli clones and the source organisms. the inaz protein appeared in p. syringae s203 during stationary phase; its appearance was correlated with the ...19883123461
investigation by electron paramagnetic resonance spectroscopy of the molybdenum centre of respiratory nitrate reductase from paracoccus denitrificans.the molybdenum centre of respiratory nitrate reductase from paracoccus denitrificans has been investigated by e.p.r. spectroscopy of mo(v). in common with the centres of the analogous enzymes from escherichia coli and pseudomonas aeruginosa, it undergoes a ph- and anion-dependent transition between two different e.p.r. signal-giving species. comparison of the relevant e.p.r. parameters extracted with the help of computer simulations reveals ligation of the metal in the active centres of the thre ...19882844161
physical and functional analyses of the syra and syrb genes involved in syringomycin production by pseudomonas syringae pv. syringae.the syra and syrb genes involved in syringomycin production in pseudomonas syringae pv. syringae b301d were identified from an ecori-plafr3 cosmid library and then physically and functionally analyzed in relation to plant pathogenicity. homologous recombination of the genes required for syringomycin production from cosmids pgx183 (syra) and pgx56 (syrb), respectively, introduced into nontoxigenic (tox-) tn5 mutants w4s2545 and w4s770 resulted in the concomitant restoration of toxin production an ...19882848010
genetic organization and regulation of proteins associated with production of syringotoxin by pseudomonas syringae pv. syringae.many strains of pseudomonas syringae pv. syringae produce one of two low-molecular-weight, peptide-containing phytotoxins, either syringomycin (sr) or syringotoxin (st). an analysis of tn5-induced st-mutants revealed alterations in the presence of two large proteins (ca. 470 and 435 kilodaltons). apparent truncated forms of the 470 (st1)- or 435 (st2)-kilodalton proteins were observed in some mutants. mapping of the tn5 insertions and size determinations of truncated proteins suggested that both ...19882848011
investigation by electron paramagnetic resonance spectroscopy of the molybdenum centre of respiratory nitrate reductase from paracoccus denitrificans.the molybdenum centre of respiratory nitrate reductase from paracoccus denitrificans has been investigated by e.p.r. spectroscopy of mo(v). in common with the centres of the analogous enzymes from escherichia coli and pseudomonas aeruginosa, it undergoes a ph- and anion-dependent transition between two different e.p.r. signal-giving species. comparison of the relevant e.p.r. parameters extracted with the help of computer simulations reveals ligation of the metal in the active centres of the thre ...19882844161
deletion mutagenesis of the ice nucleation gene from pseudomonas syringae s203.the ice nucleation gene inaz, from pseudomonas syringae s203, was manipulated to produce a series of defined rearrangements in its coding sequence without changing the reading frame. the effects of these mutations on the ice nucleation phenotype were determined in a heterologous host, escherichia coli k12. deletions which disrupted the periodicity of 16 codons, in a repetitive region of inaz, caused the frequencies of ice nuclei in the bacterial population to be significantly depressed; the nucl ...19882853829
[antigenic polysaccharides of bacteria. 26. structure of o-specific polysaccharides from pseudomonas cerasi 467 and pseudomonas syringae pv. syringae strains 218 and p-55 belonging to serogroups ii and iii].serologically active o-specific polysaccharides were obtained on mild acid hydrolysis of lipopolysaccharides from pseudomonas cerasi 467 and pseudomonas syringae pv. syringae strains 218 and p-55. on the basis of 1h- and 13c-nmr analysis, it was concluded that the p. cerasi polysaccharide has the following structure: ----3)-alpha-d-rhap-(1----3)-alpha-d-rhap-(1----2)-alpha-d-+ ++rhap-(1---- which is identical to that of o-specific polysaccharide from p. syringae pv. morsprunorum c28 (smith a. r. ...19882454625
[antigenic polysaccharides of bacteria. 27. structure of the o-specific polysaccharide chain of lipopolysaccharides from pseudomonas syringae pv. atrofaciens 2399, phaesolica 120a and pseudomonas holci 8299 belonging to serotype vi].lipopolysaccharides from pseudomonas syringae pvs atrofaciens 2399. phaseolicola 120a and pseudomonas holci 8299, belonging to serogroup vi. possess an identical polysaccharide chain composed of d-rhamnose and d-fucose. on the hasis of methylation, partial acid hydrolysis, 1h- and 13c-nmr data, it was concluded that the backbone of the polysaccharide represents d-rhamnan built up of tetrasaccharide repeating units and alpha-d-fucofuranose residues are attached to the backbone as the monosacchari ...19882454626
[antigenic bacterial polysaccharides. 28. the structure of the o-specific lipopolysaccharide chain of pseudomonas syringae pv. atrofaciens k-1025 and pseudomonas holci 90a (serogroup ii)].lipopolysaccharides of serologically related strains of pseudomonas syringae pv. atrofaciens k-1025 and pseudomonas holci 90a possess the identical o-specific polysaccharide chains, representing a homopolymer of d-rhamnose. on the basis of methylation, partial and complete smith degradation, and analysis by 1h- and 13c-nmr-spectroscopy, it was concluded that the repeating unit of the polysaccharide is a branched pentasaccharide of the following structure: (formula; see text)19882454627
[antigenic bacterial polysaccharides. 30. the structure of the polysaccharide chain of lipopolysaccharide of pseudomonas syringae pv. syringae 281 (serogroup i)].anomeric methyl 3-o-(d-mannopyranosyl- and l-rhamnopyranosyl)-beta-d-talopyranosides were synthesised by the stereoselective 1,2-cis- and 1,2-trans manno- and rhamnosylation of methyl 2,4,6-tri-o-acetyl-beta-d-talopyranoside, which has been prepared from methyl beta-d-galactopyranoside by a synthetic scheme including conversion of the c2 configuration. from 13c-nmr spectra of the disaccharides obtained the spectral alpha- and beta-effects of o3-glycosylation of talopyranose were determined.19882454629
induction of the copper resistance operon from pseudomonas syringae.cupric sulfate induced mrna specific to the copper resistance gene cluster previously cloned from pseudomonas syringae pv. tomato pt23. mrna from each of the four genes of this cluster responded in a similar manner to induction over time and with different concentrations of cupric sulfate. promoter fusion constructs indicated the presence of a single copper-inducible promoter upstream from the first open reading frame.19882457580
phosphorylation of synthetic random polypeptides by protein kinase p and other protein-serine (threonine) kinases and stimulation or inhibition of kinase activities by microbial toxins.a synthetic random polymer of threonine and glutamate (1:4.4) is readily phosphorylated by protein kinase p but not by five other protein-serine (threonine) kinases. a synthetic random polymer of serine and arginine (1:3) is readily phosphorylated by protein kinase a and protein kinase c but not by protein kinase p. although the amino acid sequences surrounding the phosphorylated serine (threonine) residue have been demonstrated in studies with small synthetic polypeptides to be decisive factors ...19883125547
role of indoleacetic acid-lysine synthetase in regulation of indoleacetic acid pool size and virulence of pseudomonas syringae subsp. savastanoi.the phytopathogen pseudomonas syringae subsp. savastanoi incites the production of galls on olive and oleander plants. gall formation is dependent upon the bacterial synthesis of the phytohormone indole-3-acetic acid (iaa). strains isolated from oleander galls are capable of further metabolizing iaa to an amino acid conjugate, 3-indoleacetyl-epsilon-l-lysine (iaa-lysine); bacterial olive gall isolates lack this activity. in this study, the cloned gene for iaa-lysine synthetase (iaal+) was introd ...19883129408
molecular cloning of a pseudomonas syringae pv. syringae gene cluster that enables pseudomonas fluorescens to elicit the hypersensitive response in tobacco plants.a cosmid clone isolated from a genomic library of pseudomonas syringae pv. syringae 61 restored to all tn5 mutants of this strain studied the ability to elicit the hypersensitive response (hr) in tobacco. cosmid phir11 also enabled escherichia coli tb1 to elicit an hr-like reaction when high levels of inoculum (10(9) cells per ml) were infiltrated into tobacco leaves. the cosmid, which contains a 31-kilobase dna insert, was mobilized by triparental matings into pseudomonas fluorescens 55 (a nonp ...19883139635
characterization and expression of two avirulence genes cloned from pseudomonas syringae pv. glycinea.two avirulence genes, avrb and avrc, from race 0 of pseudomonas syringae pv. glycinea, were sequenced and found to encode single protein products of 36 and 39 kilodaltons, respectively. the proteins had neither recognizable signal peptide sequences nor significant stretches of hydrophobic amino acids that might indicate membrane association. both avrb and avrc had relatively low position 3 and overall g+c contents, which suggests that they may have been recently introduced into p. syringae pv. g ...19883049552
chemical crosslinking of bacteriophage phi 6 nucleocapsid proteins.phi 6 is a lipid-containing dsrna bacteriophage of pseudomonas syringae. its nucleocapsid (nc) has common features with reoviridae core particles. we report here the crosslinking of phi 6 nc proteins with cleavable 12-a span chemical crosslinker, dithiobis(succinimidyl propionate). the crosslinked complexes were analyzed in two-dimensional polyacrylamide gels or by using monoclonal antibodies to uncleaved protein complexes in one-dimensional protein gels. the nc surface protein (p8) forms a seri ...19883043894
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 ...19883290199
molecular analysis of a pathogenicity locus in pseudomonas syringae pv. syringae.one of the chromosomal regions of pseudomonas syringae pv. syringae encoding pathogenicity factors had been mapped into a 3.9-kilobase-pair fragment in previous studies. promoter probe analysis indicated the existence of a promoter near one end of the fragment. dna sequencing of this fragment revealed the existence of a consensus promoter sequence in the region of the promoter activity and two open reading frames (orfs) downstream. these orfs, orf1 and orf2, encoded putative polypeptides of 40 a ...19883192509
[detection and characterization of a levansucrase and a sucrase in pseudomonas syringae pv. phaseolicola].pseudomonas syringae pv. phaseolicola, a plant pathogenic pseudomonad, possesses two sucrose-splitting enzymes, a levansucrase and a sucrase. the levansucrase is found both extracellularly and intracellularly, and enzyme synthesis is independent of the carbon source. in addition to levansucrase, cells grown on sucrose contain a sucrase. the two sucrose-splitting enzymes differ in their optimum ph value and optimum temperature as well as in their substrate specificities.19883236222
the avirulence gene avrbs1 from xanthomonas campestris pv. vesicatoria encodes a 50-kd protein.a gene cloned from xanthomonas campestris pv. vesicatoria race 2, avrbs1, specified avirulence on pepper cultivars containing the resistance gene bs1. a series of exonuclease iii deletions were made on a 3.2-kbp dna fragment that determined full avirulence activity, observed as hypersensitive response (hr) induction. the deletion products were subcloned into the broad host range cloning vector plafr3, conjugated into a virulent x. c. pv. vesicatoria race 1 strain, 82-8, and scored for their abil ...19882979910
the nucleocapsid of bacteriophage phi 6 penetrates the host cytoplasmic membrane.bacteriophage phi 6 infects its host, the gram-negative bacterium pseudomonas syringae, by a protein-targeted fusion of the virus envelope with the host outer membrane. in this investigation we present results suggesting that the phage nucleocapsid penetrates the host cytoplasmic membrane via a membrane invagination and an intracellular vesicle. this indicates that the prokaryotic plasma membrane might be more dynamic and have more common features with eukaryotic membrane systems than previously ...19883169005
nonlinear relationship between concentration and activity of a bacterial ice nucleation protein.the expression level of an ice nucleation gene (inaz) was varied in escherichia coli to observe the relationship between activity and gene product. the ice nucleation activity increased as the 2nd to 3rd power of the membrane concentration of the inaz gene product, implying that molecules of inaz protein interact cooperatively in groups of two to three at the rate-limiting step of ice nucleus assembly. the 2nd to 3rd power relationship was independent of the threshold temperature at which ice nu ...19883049605
size of bacterial ice-nucleation sites measured in situ by radiation inactivation analysis.four bacterial species are known to catalyze ice formation at temperatures just below 0 degrees c. to better understand the relationship between the molecular structure of bacterial ice-nucleation site(s) and the quantitative and qualitative features of the ice-nucleation-active phenotype, we determined by gamma-radiation analysis the in situ size of ice-nucleation sites in strains of pseudomonas syringae and erwinia herbicola and in escherichia coli hb101 carrying the plasmid pice1.1 (containin ...198816593912
chemotaxis by pseudomonas syringae pv. tomato.optimal laboratory conditions for studying chemotaxis by pseudomonas syringae pv. tomato were determined by using the adler capillary tube assay. although they are not an absolute requirement for chemotaxis, the presence of 0.1 mm edta and 1 mm mgcl(2) in the chemotaxis buffer (10 mm potassium phosphate [ph 7.2]) significantly enhanced the response to attractant. the addition of mannitol as an energy source had little effect. the optimal temperature for chemotaxis was 23 degrees c, which is 5 de ...198816347574
effect of plant species and environmental conditions on ice nucleation activity of pseudomonas syringae on leaves.selected plant species and environmental conditions were investigated for their influences on expression of ice nucleation activity by 15 pseudomonas syringae strains grown on plants in constant-temperature growth chamber studies. ice nucleation frequencies (infs), the fraction of cells that expressed ice nucleation at -5 or -9 degrees c, of individual strains varied greatly, both on plants and in culture. this suggests that the probability of frost injury, which is proportional to the number of ...198816347741
evaluation of the role of syringomycin in plant pathogenesis by using tn5 mutants of pseudomonas syringae pv. syringae defective in syringomycin production.syringomycin is a necrosis-inducing phytotoxin produced by pseudomonas syringae pv. syringae. to determine whether syringomycin production is a determinant in virulence or pathogenicity, we isolated nontoxigenic (tox) tn5-containing mutants and then quantitatively evaluated them for the ability to multiply and cause disease in immature sweet-cherry fruits. transposon tn5 was delivered to tox strain b301d-r by using the suicide vector, pgs9, and the resultant kanamycin-resistant (km) colonies wer ...198816347644
aerial dispersal and epiphytic survival of pseudomonas syringae during a pretest for the release of genetically engineered strains into the environment.prospective experimental field evaluation of genetically engineered microorganisms, such as microbial pest control agents, raises issues of how to properly ascertain their fate and survival in the environment. field trials with recombinant organisms must reflect requirements for sampling and monitoring. field trials were conducted at tulelake, calif., to monitor the numbers of viable cells of a nonrecombinant strain of pseudomonas syringae that entered the atmosphere and landed on plants and soi ...198816347666
oats tolerant of pseudomonas syringae pv. tabaci contain tabtoxinine-beta-lactam-insensitive leaf glutamine synthetases.pseudomonas syringae pv. tabaci, a commonly recognized leaf pathogen of tobacco, can infest the rhizosphere of many plants, including oats. normal oat plants do not survive this infestation as a consequence of the complete and irreversible inactivation of all of their glutamine synthetases by tabtoxinine-beta-lactam (tbetal), a toxin released by pv. tabaci. we have identified a population of oat (avena sativa l. var lodi) plants that are tolerant of pv. tabaci. the tolerant plants had no detecta ...198816666304
development, distribution, and characteristics of intrinsic, nonbacterial ice nuclei in prunus wood.ice nuclei active at approximately -2 degrees c and intrinsic to woody tissues of prunus spp. were shown to have properties distinct from bacterial ice nuclei. soaking 5-centimeter peach stem sections in water for 4 hours lowered the mean ice nucleation temperature to below -4 degrees c, nearly 2 degrees c lower than stems inoculated with ice nucleation-active pseudomonas syringae strain b301d. ice nucleation activity in peach was fully restored by air-drying woody stem sections for a few hours. ...198816666404
cloned avirulence genes from the tomato pathogen pseudomonas syringae pv. tomato confer cultivar specificity on soybean.three different cosmid clones were isolated from a genomic library of the tomato pathogen pseudomonas syringae pv. tomato, which, when introduced into the soybean pathogen p. syringae pv. glycinea, caused a defensive hypersensitive response (hr) in certain soybean cultivars. each clone was distinguished by the specific cultivars that reacted hypersensitively and by the intensity of the hr elicited. unlike wild-type p. syringae pv. tomato isolates, which elicit the hr on all soybean cultivars, al ...198916578838
characterization of vacuolar and extracellular beta(1,3)-glucanases of tobacco: evidence for a strictly compartmentalized plant defense system.beta(1,3)-glucanases are a class of hormonally and developmentally regulated plant hydrolytic enzymes, which are also induced upon pathogen infection, suggesting a role of these hydrolases in the defense response to pathogens. we have purified several beta(1,3)-glucanases present in tobacco leaves from control plants and from plants treated with salicylic acid or infected with pseudomonas syringae and studied in detail the subcellular localization of the different isoforms. partial protein seque ...198916594025
exopolysaccharides produced by phytopathogenic pseudomonas syringae pathovars in infected leaves of susceptible hosts.bacterial exopolysaccharide (eps) was extracted from infected leaves of several host plants inoculated with phytopathogenic strains of pseudomonas syringae pathovars. extraction was by a facilitated diffusion procedure or by collection of intercellular fluid using a centrifugation method. the extracted eps was purified and characterized. all bacterial pathogens which induced watersoaked lesions on their host leaves, a characteristic of most members of this bacterial group, were found to produce ...198916666545
effects of singlet oxygen quenchers and ph on the bacterially induced hypersensitive reaction in tobacco suspension cell cultures.suspension cell cultures of nicotiana tabacum l. inoculated with the incompatible pathogen pseudomonas syringae pv pisi undergo a hypersensitive reaction. addition of the singlet oxygen quencher bixin to cell suspensions had no effect on hypersensitive cell death. addition of the singlet oxygen quencher 1,4-diazabicyclo octane (dabco) increased the medium ph and delayed the onset of cell death. this delay was eliminated when cell suspensions were buffered, and could also be induced by increasing ...198916666744
role of the plasmalemma h-atpase in pseudomonas syringae-induced k/h exchange in suspension-cultured tobacco cells.activation of a host plasma membrane k(+) efflux/net h(+) uptake exchange by pathogenic pseudomonads plays an important role in the development of hypersensitivity in tobacco (nicotiana tabacum). involvement of the plasmalemma h(+)-pumping atpase in this response was investigated. the exchange response of suspension-cultured tobacco cells to pseudomonas syringae pv syringae was reduced 90% or more by atpase inhibitors including vanadate, n-ethylmaleimide, and n,n'-dicyclohexylcarbodiimide. the e ...198916667014
increase of chalcone synthase mrna in pathogen-inoculated soybeans with race-specific resistance is different in leaves and roots.soybeans (glycine max [l.] merr.) respond to pathogens by producing isoflavonoid-derived phytoalexins. chalcone synthase (chs) is the first enzyme of the flavonoid/isoflavonoid biosynthetic pathway. we investigated changes in the steady state levels of chs mrna and other specific mrnas at increasing times after inoculation in two different race-specific interactions, one between leaves and the bacterium pseudomonas syringae pv glycinea (psg), and one between roots and the fungus, phytophthora me ...198916667156
diel variation in population size and ice nucleation activity of pseudomonas syringae on snap bean leaflets.the extent to which diel changes in the physical environment affect changes in population size and ice nucleation activity of pseudomonas syringae on snap bean leaflets was determined under field conditions. to estimate bacterial population size and ice nucleation activity, bean leaflets were harvested at 2-h intervals during each of three 26-h periods. a tube nucleation test was used to assay individual leaflets for ice nuclei. population sizes of p. syringae were determined by dilution plating ...198916347871
survival of ice nucleation-active and genetically engineered non-ice-nucleating pseudomonas syringae strains after freezing.the survival after freezing of ice nucleation-active (ina) and genetically engineered non-ina strains of pseudomonas syringae was compared. each strain was applied to oat seedlings and allowed to colonize for 3 days, and the plants were subjected to various freezing temperatures. plant leaves were harvested before and after freezing on two consecutive days, and bacterial populations were determined. populations of the ina wild-type strain increased 15-fold in the 18 h after the oat plants incurr ...198916347963
response of plant-colonizing pseudomonads to hydrogen peroxide.colonization of plant root surfaces by pseudomonas putida may require mechanisms that protect this bacterium against superoxide anion and hydrogen peroxide produced by the root. catalase and superoxide dismutase may be important in this bacterial defense system. stationary-phase cells of p. putida were not killed by hydrogen peroxide (h(2)o(2)) at concentrations up to 10 mm, and extracts from these cells possessed three isozymic bands (a, b, and c) of catalase activity in native polyacrylamide g ...198916348058
scanning electron microscopy of invasion of apple leaves and blossoms by pseudomonas syringae pv. syringae.scanning electron microscopy indicated that pseudomonas syringae pv. syringae l795 entered leaves through stomata and multiplied in the substomatal chambers. strain l195 applied to blossoms colonized stigmas and also occurred in intercellular spaces of styles. nonpathogenic strain l796 failed to colonize blossoms. this study suggests that inoculum of pathogenic p. syringae pv. syringae builds up on apple leaves and blossoms.198916347862
corrigenda: an ice nucleation reporter gene system: identification of inducible pathogenicity genes in pseudomonas syringae pv. phaseolicola.[this corrects the article on p. 1291 in vol. 8, pmid: 2548841.].198916453893
properties and partial genetic characterization of nepean phage and other lytic phages of brucella species.nepean (np), a new brucellaphage, was associated with atypical brucella abortus strains from ontario cattle. carriage of np was associated with loss of smooth lipopolysaccharide, changes in some protein bands in acrylamide gel electrophoresis profiles, increased susceptibility to colistin, and increased resistance to ultraviolet killing. nepean (np) was compared with brucellaphages tb, fi, wb, iz and r/c. all were morphologically identical, with icosahedral capsids (50-65 nm diameter) and short ...19892504475
localization of ice nucleation activity and the icec gene product in pseudomonas syringae and escherichia coli.ice nucleation activity and the icec gene product were quantified in different subcellular fractions of the pseudomonas syringae source strain and in escherichia coli containing the cloned icec gene to determine the activity of this protein in different subcellular locations. ice nuclei were nearly completely retained during isolation of cell envelopes but exhibited a decrease in the temperature at which they were expressed. ice nucleation activity was found in triton x-100 insoluble membrane fr ...19892520825
the consensus sequence of ice nucleation proteins from erwinia herbicola, pseudomonas fluorescens and pseudomonas syringae.the consensus sequence of three bacterial ice nucleation proteins was determined by extrapolation from the nucleotide (nt) sequences of three ice nucleation-encoding genes, icee (presented here), inaw and inaz. the three proteins possess considerable similarity, so that a preferred amino acid is shown in most positions of the consensus. the corresponding genes show considerable divergence in the third nt positions of synonymous codons, suggesting that the proteins' conserved features have been m ...19892515997
plasmid-mediated production of the phytotoxin coronatine in pseudomonas syringae pv. tomato.pseudomonas syringae pv. tomato pt23.2 produces the chlorosis-inducing phytotoxin coronatine. thirty-eight chlorosis-defective mutants of pt23.2 were previously generated by using the transposon tn5. five mutants contained tn5 insertions in the indigenous plasmid ppt23a; the remaining 33 mutants either were missing ppt23a (29 mutants) or contained deletions in this plasmid (4 mutants). these results suggested that ppt23a was involved in coronatine production in strain pt23.2. this plasmid was in ...19892536682
the induction of manganese superoxide dismutase in response to stress in nicotiana plumbaginifolia.superoxide dismutases (sods) are metalloproteins that catalyse the dismutation of superoxide radicals to oxygen and hydrogen peroxide. the enzyme has been found in all aerobic organisms examined, where it plays a major role in the defence against toxic reduced oxygen species which are generated in many biological oxidations. here we report the complete primary structure of a plant manganese superoxide dismutase (mnsod), deduced from a cdna clone of nicotiana plumbaginifolia. the plant protein is ...19892540959
phaseolotoxin production by pseudomonas syringae pv. phaseolicola: the influence of temperature.phaseolotoxin (n-sulphodiaminophosphinyl-ornithyl-alanyl-homoarginine) is a phytotoxic secondary metabolite produced by pseudomonas syringae pv. phaseolicola. the production of the phytotoxin is strongly regulated by temperature. the optimal temperature for phaseolotoxin production is 18 degrees c. temperatures in the range between 18 degrees c and 30 degrees c inhibit the production of phaseolotoxin in an increasing manner. by temperature shift experiments and the inhibition of protein synthesi ...19892600779
[the plasmids of pseudomonas syringae].the paper deals with occurrence of plasmids in p. syringae strains belonging to seventeen pathovars: the strains were isolated in the ussr and other countries. one to four different plasmids having molecular weights of 20 to 90 md have been found in various strains of the following twelve pathovars: holci, cerasi, aptata, tabaci, populi, pisi, lupini syringae, lachrymans, phaseolicola, glycinea, atrofaciens. both virulent and avirulent p. syringae strains appear to carry such plasmids. plasmids ...19892621286
induction of potassium efflux by cupric ions in pseudomonas syringae atcc 12271 and its correlation with cell viability.in pseudomonas syringae, cu2+ induce a significant loss of k+ from the cells. the course of the efflux followed an approximately sigmoidal pattern. the maximum rate of k+ efflux, the time needed to achieve this rate and the maximum amount of k+ released from the cells, were dependent on copper concentration. pre-treatment with several divalent cations modified markedly the parameters of potassium efflux induced by copper, by increasing the maximum rate of k+ efflux and the amount of k+ released ...19892615669
[lytic activity of pseudomonas bacteriophages].none of the 24 pseudomonas syringae bacteriophages were found to be identical in the spectrum of lytic action. the phages were subdivided into five groups according to the number of sensitive bacterial strains and their qualitative composition.19892635268
cotranscription of genes encoding indoleacetic acid production in pseudomonas syringae subsp. savastanoi.indoleacetic acid (iaa) production by the plant pathogen pseudomonas syringae subsp. savastanoi is essential for tumor formation on olive and oleander. the bacterium produces iaa from tryptophan in reactions catalyzed by tryptophan monooxygenase and indoleacetamide hydrolase. the genetic determinants are, respectively, iaam and iaah. in oleander isolates, the genes encoding the iaa biosynthetic enzymes are located on a plasmid; in olive isolates, the genes occur on the chromosome. the iaa genes ...19892644217
survival and detection of bacteria in an aquatic environment.a genetically engineered plasmid, ppsa131, was used as a dna probe to detect homologous dna in escherichia coli hb101(ppsa131) after it was mixed with aquatic microorganisms from lake mead, nevada, water samples. an isolate from the plafr1 chromosomal library of pseudomonas syringae cit 7 was used to detect parent p. syringae cit 7 that had been mixed with lake mead water. e. coli(ppsa131) was kept in variously treated samples of lake water or buffer, and its survival was measured by viable cell ...19892658805
major integral membrane protein immunogens of treponema pallidum are proteolipids.a number of the major pathogen-specific immunogens of treponema pallidum were characterized recently as amphiphilic, integral membrane proteins by phase partitioning with triton x-114 (j. d. radolf, n. r. chamberlain, a. clausell, and m. v. norgard. infect. immun. 56:490-498, 1988). in the present study, we demonstrated that the same membrane immunogens (designated as detergent phase proteins [dpps]) become radiolabeled upon in vitro incubation of t. pallidum with various 3h-labeled fatty acids. ...19892668191
the structure of syringomycins a1, e and g.by a combination of 1d and 2d 1h- and 13c-nmr, fab-ms, and chemical and enzymatic reactions carried out at the milligram level, it has been demonstrated that syringomycin e, the major phytotoxic antibiotic produced by pseudomonas syringae pv. syringae, is a new lipodepsipeptide. its amino acid sequence is ser-ser-dab-dab-arg-phe-dhb-4(cl)thr-3(oh)asp with the beta-carboxy group of the c-terminal residue closing a macrocyclic ring on the oh group of the n-terminal ser, which in turn is n-acylated ...19892676599
quantitation of the adsorption and penetration stages of bacteriophage phi 6 infection.the enveloped dsrna bacteriophage phi 6 uses the pilus of pseudomonas syringae as its receptor. it enters the host cell by fusion of the virus envelope with the host outer membrane, followed by penetration of the cytoplasmic membrane by the phage nucleocapsid. in this investigation we quantitated the adsorption and penetration of phi 6wt and a host range mutant, phi 6h 1s, to five bacterial strains. adsorption rate constants were measured for the different phage-host combinations, the constant f ...19892741342
influence of pseudomonas syringae culture conditions on initiation of the hypersensitive response of culture tobacco cells.the inhibitor sensitivity and timing of the ionic response of suspension-cultured tobacco cells were used as a bioassay for the pseudomonas syringae signal that elicits the hypersensitive response in resistant plants. the ionic response of tobacco cell suspensions inoculated with p. syringae pv. syringae 61 and p. syringae pv. pisi grown in rich media was inhibited by rifampin, tetracycline, and streptomycin during a 2- to 2.5-h induction stage. coculturing the bacteria with tobacco cells for 3 ...19892764576
the predicted protein product of a pathogenicity locus from pseudomonas syringae pv. phaseolicola is homologous to a highly conserved domain of several procaryotic regulatory proteins.a ca. 20-kilobase (kb) region (hrp) that controls the interaction of pseudomonas syringae pv. phaseolicola with its host (pathogenicity) and nonhost plants (hypersensitive reaction) was previously cloned and partially characterized. in this study we defined the limits and determined the nucleotide sequence of a hrp locus (hrps), located near the right end of the hrp cluster. the largest open reading frame (orf302) in hrps has a coding capacity for a 302-amino-acid polypeptide. the predicted amin ...19892768197
detection of an insensitive ornithine-carbamoyltransferase in strains of pseudomonas syringae pv. phaseolicola with different phytotoxin-generating capacities.independently of their capacity to produce phytotoxins, strains of pseudomonas syringae pv. phaseolicola contain two ornithine carbamoyltransferases (oct, ec 2.1.3.3) which differ in resistance to phaseolotoxin and orn-p(o) (nh2)-nh-so3 h (pnsorn). at 18 degrees c, the optimal temperature for product formation, the balance of the two types of oct was shifted in favour of the insensitive type in phaseolotoxin producing strains, and in favour of the sensitive one in strains with little or no toxin ...19892778648
inhibition of ornithine carbamoyltransferase from pseudomonas syringae pv. syringae w50 by phaseolotoxin.in contrast to the producer of phaseolotoxin and orn-p(o)(nh2)-nh-so3h (pnsorn), pseudomonas syringae pv. phaseolicola, which possesses a sensitive and an insensitive type of ornithine carbamoyltransferase (oct, e.c. 2.1.3.3.), in pseudomonas syringae pv. syringae w50, an organism which produce neither phaseolotoxin nor pnsorn, only one type of oct could be detected. this enzyme is highly sensitive to phaseolotoxin. this result supports our hypothesis that the existence of an insensitive ornithi ...19892778649
bacterial blight of soybean: regulation of a pathogen gene determining host cultivar specificity.soybean cultivars resistant to pseudomonas syringae pathovar glycinea (psg), the causal agent of bacterial blight, exhibit a hypersensitive (necrosis) reaction (hr) to infection. psg strains carrying the avrb gene elicit the hr in soybean cultivars carrying the resistance gene rpg1. psg expressing avrb at a high level and capable of eliciting the hr in the absence of de novo bacterial rna synthesis have been obtained in in vitro culture. nutritional signals and regions within the psg hrp gene cl ...19892781284
an ice nucleation reporter gene system: identification of inducible pathogenicity genes in pseudomonas syringae pv. phaseolicola.we have constructed derivatives of the transposon tn3 that allow an ice nucleation gene (inaz) to be used as 'reporter' of the transcriptional activity of genes into which it is inserted. in these derivatives (tn3-ice and tn3-spice), the laczya sequences of transposon tn3-hoho1 were replaced with inaz lacking its native promoter. the ice nucleation activity of virb::inaz fusions in the correct transcriptional orientation was inducible by acetosyringone, a plant metabolite which activates the vir ...19892548841
a single oligonucleotide can be used to rapidly isolate dna sequences flanking a transposon tn5 insertion by the polymerase chain reaction.we have developed a strategy to rapidly construct dna hybridization probes for the isolation of genes disrupted by transposon tn5 insertions. a single oligonucleotide complementary to and extending outward from the ends of the inverted repeat of tn5 was used to prime dna synthesis in the polymerase chain reaction. the amplified product consisted of dna sequences adjacent to both ends of the transposon insertion. the general feasibility of the approach was tested by amplifying pbr322 sequences fr ...19902174544
[isolation and partial characteristics of biopolymers in the outer membrane of pseudomonas syringae].conditions are developed for obtaining extracellular biopolymers (ebp), water (w), salt-edta (se) and salt-detergent (sd) extracts of pseudomonas syringae pv. atrofaciens imv k-1025. the fraction of unsoluble lps is effectively precipitated from samples by ultracentrifugation (uc). the fractions enriched by proteins and soluble lps are salted-out from the uc supernatants by ammonium sulphate, that is confirmed by the chemical analysis, electrophoresis in the paag-nds and in elisa with the monocl ...19902368185
biological activities of racemomycin-b, beta-lysine rich streptothricin antibiotic, the main component of streptomyces lavendulae op-2.racemomycin-b (rm-b), the main component of streptomyces lavendulae op-2 which is the basis of 50% of the antibiotics produced, is a streptothricin antibiotic which contains three beta-lysine moieties in the molecule. rm-b had antimicrobial activity against plant-pathogenic microorganisms and growth-inhibitory activity against the root of brassica rapa l. at the concentration of 50 ppm. it strongly inhibited the growth of pseudomonas syringae pv. tabaci ifo-3508 (minimum inhibitory concentration ...19902177682
structure of syringotoxin, a bioactive metabolite of pseudomonas syringae pv. syringae.the covalent structure of syringotoxin, a bioactive metabolite of pseudomonas syringae pv. syringae isolates, pathogenic on various species of citrus trees, has been deduced from 1d and 2d 1h- and 13c-nmr spectra combined with extensive fab-ms data and results of some chemical reactions. similarly to syringomicins and syringostatins, produced by other plant pathogenic strains of p. syringae pv. syringae, syringotoxin is a lipodepsinonapeptide. its peptide moiety corresponds to ser-dab-gly-hse-or ...19902401362
inhibition by agrobacterium tumefaciens and pseudomonas savastanoi of development of the hypersensitive response elicited by pseudomonas syringae pv. phaseolicola.injection into tobacco leaves of biotype 1 agrobacterium tumefaciens or of pseudomonas savastanoi inhibited the development of a visible hypersensitive response to the subsequent injection at the same site of pseudomonas syringae pv. phaseolicola. this interference with the hypersensitive response was not seen with injection of bacterial growth medium or escherichia coli cells. live a. tumefaciens cells were required for the inhibitory effect. various mutants and strains of a. tumefaciens were e ...19902211508
purified phi 6 nucleocapsids are capable of productive infection of host cells with partially disrupted outer membranes.purified nucleocapsids of bacteriophage phi 6, lacking the phage lipid envelope, are unable to infect intact pseudomonas syringae host cells. a method for studying the process by which a naked virus particle, the phi 6 nucleocapsid, penetrates the host cytoplasmic membrane was developed. host cells were rendered competent for nucleocapsid infection by treatment with repeated washings with salt and sucrose and the subsequent addition of lysozyme. this treatment disrupts the outer membrane, permit ...19902219699
purification, cloning, and primary structure of an enantiomer-selective amidase from brevibacterium sp. strain r312: structural evidence for genetic coupling with nitrile hydratase.an enantiomer-selective amidase active on several 2-aryl and 2-aryloxy propionamides was identified and purified from brevibacterium sp. strain r312. oligonucleotide probes were designed from limited peptide sequence information and were used to clone the corresponding gene, named amda. highly significant homologies were found at the amino acid level between the deduced sequence of the enantiomer-selective amidase and the sequences of known amidases such as indoleacetamide hydrolases from pseudo ...19902254253
conserved repetition in the ice nucleation gene inax from xanthomonas campestris pv. translucens.the nucleotide sequence was determined for the bacterial ice nucleation gene, inax, from xanthomonas campestris pathovar translucens x56s. comparison of the nucleotide sequence of inax to the previously characterized ice nucleation genes, inaz from pseudomonas syringae s203, inaw from pseudomonas fluorescens ms1650, and icee from erwinia herbicola m1 revealed a 65.8%, 67.8%, and 68.8% homology, respectively. within the internal, repetitive domain of the translated product of inax are 153 consecu ...19902259339
subacute inhalation toxicity study of an ice-nucleation-active pseudomonas syringae administered as a respirable aerosol to rats.the inhalation toxicity of a commercial sample of an ice-nucleation-active pseudomonas syringae (strain 31a) was evaluated by repetitively exposing rats to about 700 mg/m3 of an aerosol consisting of a suspension of 0.0008, 0.4 or 0.8 g/l of bacteria in water for 2 h per day, 5 days per week for 13-14 exposures. no mortality, moribundity or biologically significant differences in clinical signs, body weight, food consumption or clinical pathology were observed. animals tested at 500 times (0.4 g ...19902260113
effects of betaine on enumeration of airborne bacteria.the osmoprotectant betaine was incorporated into collection fluid and enumeration medium to determine its effects on the colony-forming abilities of airborne bacteria, which were collected from three separate locations: a wastewater treatment plant, the roof of a laboratory building, and an unobstructed farmland. at all locations, addition of 2 to 5 mm betaine caused a significant increase (from 21.6 to 61.3%) in colonial outgrowth, compared with the growth rate of controls without betaine. the ...19902339884
[the specificity of an immune serum to the exocellular lipopolysaccharide of pseudomonas wieringae].the serum obtained to exocellular lipopolysaccharide (elps) of pseudomonas wieringae selectively agglutinated strains of pathovar of p. syringae and did not agglutinated strains of p. cichorii, p. solanacearum, p. gladioli pv. allicola, p. fluoroviolaceus, strains of nonphytopathogenic pseudomonads as well as bacteria of the genera erwinia, bacillus, xanthomonas, klebsiella. consequently, the antigen determinant common with antigen of the species pseudomonas syringae is present in the compositio ...19902352502
[loquat canker: a new disease for argentina].a stem canker disease caused by pseudomonas syringae pv. eriobotryae (takimoto) young, dye y wilkie on loquat (eriobotrya japonica [thumb] lindl) was recorded for the first time in argentina. symptoms of the disease appeared as dry stem cankers which in advanced stages surrounded the stems. similar cankers were noticeable on leaves midribs. seven bacterial strains were isolated from diseased loquats and their identification was based on disease symptoms, pathogenicity and cultural and biochemica ...19902102015
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