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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
survival of bacteria during aerosolization.one form of commercial application of microorganisms, including genetically engineered microorganisms is as an aerosol. to study the effect of aerosol-induced stress on bacterial survival, nonrecombinant spontaneous antibiotic-resistant mutants of four organisms, enterobacter cloacae, erwinia herbicola, klebsiella planticola, and pseudomonas syringae, were sprayed in separate experiments in a greenhouse. samples were collected over a distance of 15 m from the spray site for enumeration. spores o ...19902268156
effect of aerosolization on subsequent bacterial survival.to determine whether aerosolization could impair bacterial survival, pseudomonas syringae and erwinia herbicola were aerosolized in a greenhouse, the aerosol was sampled at various distances from the site of release by using all-glass impingers, and bacterial survival was followed in the impingers for 6 h. bacterial survival subsequent to aerosolization of p. syringae and e. herbicola was not impaired 1 m from the site of release. p. syringae aerosolized at 3 to 15 m from the site of release at ...19902268157
isolation and characterization of the gene from pseudomonas syringae pv. phaseolicola encoding the phaseolotoxin-insensitive ornithine carbamoyltransferase.the gene coding for the phaseolotoxin-insensitive ornithine carbamoyltransferase (octase) from pseudomonas syringae pv. phaseolicola has been cloned and sequenced. the gene has a deduced coding capacity for a polypeptide with a calculated mr of 36,520 daltons. comparison of the amino acid sequence of the octase enzymes encoded by the p. aeruginosa argf and the escherichia coli argi and argf genes with the deduced sequence of the newly identified gene shows that 79 amino acid residues are strictl ...19902274044
construction of a stable shuttle vector for high-frequency transformation in pseudomonas syringae pv. syringae.a cryptic 80.3-kilobase plasmid, posu900, in pseudomonas syringae pv. syringae strain j900 could be cured by treatment with mitomycin without affecting the pathogenicity of j900 on the host, phaseolus vulgaris l. the replication region of posu900 was identified, subcloned, and modified for construction of a high-copy cloning vector. this vector could be transformed into pseudomonas strains with high efficiency (ca. 10(6) transformants per microgram of dna) and was very stable during growth of th ...19902294094
the nucleotide sequence of tabtoxin resistance gene (ttr) of pseudomonas syringae pv. tabaci. 19902336364
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
[the polysaccharide glycocalyx of pseudomonas syringae pv. atrofaciens].it was shown by the method of electron microscopy that cells of virulent strain pseudomonas syringae rv. atrofaciens 4394 have extracellular, probably, polysaccharide glycocalix. it consists of acid components giving positive cytochemical reaction with ruthenium red, a specific reagent to polyanions.19902352506
[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
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
characterization of two surface-localized antigenic sites on porin protein f of pseudomonas aeruginosa.a rapid colony immunoblot screening procedure was used to demonstrate the surface localization of porin protein f on bacterial colonies of pseudomonas aeruginosa. by this method, we demonstrated that protein f was accessible to four different specific monoclonal antibodies in a wide variety of both mucoid and nonmucoid p. aeruginosa strains. controls were performed to demonstrate that, using this procedure, only surface-exposed epitopes bound monoclonal antibodies and that nonspecific binding of ...19852408719
[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
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
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
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
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
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
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
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
[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
[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
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
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
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
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
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
function of pili in bacteriophage phi 6 penetration.the genome of bacteriophage phi 6, which has a lipid protein envelope, consists of three pieces of dsrna. virus infection is initiated by attachment to a phi 6-specific host pilus followed by fusion of the phage membrane and the bacterial outer membrane. in this study we analysed several different phi 6 hosts as well as more than 200 independently isolated phi 6-resistant variants derived from pseudomonas syringae pv. phaseolicola. it is shown that phi 6-specific pili are coded by genes located ...19852865329
role of glutamine synthetase adenylylation in the self-protection of pseudomonas syringae subsp. "tabaci" from its toxin, tabtoxinine-beta-lactam.selected pathovars of pseudomonas syringae produce an extracellular phytotoxin, tabtoxinine-beta-lactam, that irreversibly inhibits its known physiological target, glutamine synthetase (gs). pseudomonas syringae subsp. "tabaci" retains significant amounts of glutamine synthetase activity during toxin production in culture. as part of our investigation of the self-protection mechanism(s) used by these pathovars, we have determined that gs becomes adenylylated after toxin production is initiated a ...19862870053
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
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
the causal agent of halo blight in bean, pseudomonas syringae pv. phaseolicola, attaches to stomata via its pili.the phytopathogenic pseudomonad pseudomonas syringae pv. phaseolicola causes halo blight of bean (phaseolus vulgaris l.). initiation of infection depends on the ability of the cells to adhere to the target cell surface. p. syringae pv. phaseolicola expresses pili, which are the receptors of the lipid-containing dsrna bacteriophage phi 6. phi 6-resistant bacterial strains can be divided into different piliation types. it was possible to show that the adhesion of the bacteria onto plant cell surfa ...19862907769
in vitro activity of ciprofloxacin combined with azlocillin.a ciprofloxacin plus azlocillin broth microdilution checkerboard was evaluated against 125 aerobic gram-negative and gram-positive bacteria. synergism (sigma fic less than or equal to 0.5) occurred among 56% of pseudomonas aeruginosa, 30% of acinetobacter species, and 40% of staphylococcus aureus studied. antagonism (sigma fic greater than or equal to 2) was present in less than 1% of the organisms.19852935078
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
comparison of physical and genetic properties of palindromic dna sequences.some viable palindromic dna sequences were found to cause an increase in the recovery of genetic recombinants. although these palindromes contained no chi sites, their presence in cis caused apparent reca+-dependent recombination to increase severalfold. this biological property did not correlate with the physical properties of the palindromes' extrusion of cruciform structures in vitro. thus, two unrelated palindromes with similar effects on recombination in both escherichia coli and pseudomona ...19852982785
construction of a cosmid clone library of pseudomonas syringae pv. phaseolicola and isolation of genes by functional complementation.a genomic library constructed from a wild-type strain of pseudomonas syringae pv. phaseolicola in the broad-host-range cosmid vector pvk102 was used to isolate wild-type genes by complementation of tn5-induced auxotrophic mutants. selection pressure was required for maintenance of the vector and members of the library in strains of p. syringae.19852992375
isolation and characterization of tn5 insertion mutants of pseudomonas syringae pv. syringae altered in the production of the peptide phytotoxin syringotoxin.a syringotoxin-producing strain of pseudomonas syringae pv. syringae (b457) was subjected to tn5 mutagenesis by the transposon vector psup1011. analyses of auxotrophs obtained suggested simple random insertions of tn5. syringotoxin-negative mutants arose at a frequency of about 0.28%. in a southern blot analysis, the loss of toxin production was associated with tn5 insertions into chromosomal ecori fragments of about 10.5, 17.8, and 19.3 kilobases. data from a southern blot analysis of ssti-dige ...19852995307
indigenous plasmids in pseudomonas syringae pv. tomato: conjugative transfer and role in copper resistance.twenty strains of pseudomonas syringae pv. tomato were examined for the presence of plasmid dna. p. syringae pv. tomato plasmids were grouped into five size classes: class a ranged from 95 to 103 kilobases (kb); class b ranged from 71 to 83 kb; class c ranged from 59 to 67 kb; class d ranged from 37 to 39 kb; and class e was 29 kb. all strains contained at least two plasmids in classes a and b. the conjugative ability of p. syringae pv. tomato plasmids in three strains was demonstrated by mobili ...19863003029
identification and cloning of genes involved in phaseolotoxin production by pseudomonas syringae pv. "phaseolicola".genes involved in the production of phaseolotoxin by pseudomonas syringae pv. "phaseolicola" nps3121 were identified by tn5 mutagenesis and cosmid cloning. a total of 5,180 kanamycin-resistant colonies were screened for the loss of phaseolotoxin production by a microbiological assay. six independent, prototrophic, tox- mutants were isolated that had tn5 insertions in five different ecori fragments. all six mutants had tn5 inserted in the same kpni fragment, which had a length of ca. 28 kilobases ...19863011734
identification and purification of a bacterial ice-nucleation protein.the protein product of a gene (inaz) responsible for ice nucleation by pseudomonas syringae s203 has been identified and purified after overexpression in escherichia coli. the amino acid composition and the n-terminal sequence of the purified, denatured protein corresponded well with that predicted from the sequence of the inaz gene. the product of inaz was also found to be the major component in preparations of ice-nucleating, proteinaceous particles, obtained after extraction with and gel filt ...19863020542
gene cluster of pseudomonas syringae pv. "phaseolicola" controls pathogenicity of bean plants and hypersensitivity of nonhost plants.loss of the ability of pseudomonas syringae pv. "phaseolicola" nps3121 to elicit a hypersensitive response on tobacco and other nonhost plants was associated with loss of pathogenicity on the susceptible host bean. eight independent, prototrophic transposon tn5 insertion mutants which had lost the ability to elicit a hypersensitive response on tobacco plants were identified. six of these mutants no longer produced disease lesions on primary leaves of the susceptible bean cultivar red kidney and ...19863023280
cloning and regulation of erwinia herbicola pigment genes.the genes coding for yellow pigment production in erwinia herbicola eho10 (atcc 39368) were cloned and localized to a 12.4-kilobase (kb) chromosomal fragment. a 2.3-kb avai deletion in the cloned fragment resulted in the production of a pink-yellow pigment, a possible precursor of the yellow pigment. production of yellow pigment in both e. herbicola eho10 and pigmented escherichia coli clones was inhibited by glucose. when the pigment genes were transformed into a cya (adenylate cyclase) e. coli ...19863023282
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
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
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
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
cloning of the gene for indoleacetic acid-lysine synthetase from pseudomonas syringae subsp. savastanoi.the phytopathogen pseudomonas syringae subsp. savastanoi incites the production of galls on olive and oleander plants. gall formation is dependent on bacterial production of the phytohormone indoleacetic acid (iaa). the genetic determinants for iaa synthesis are located on a plasmid (piaa) and are organized in an operon in oleander strains of the bacterium. p. syringae subsp. savastanoi further converts iaa to an amino acid conjugate, 3-indole-acetyl-epsilon-l-lysine (iaa-lysine). the gene for i ...19863084452
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
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
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
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
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
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
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
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
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
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
[lipopolysaccharides of the s- and r-forms of pseudomonas syringae pv. phaseolica]. 19873508945
nucleotide sequence and expression of a pseudomonas savastanoi cytokinin biosynthetic gene: homology with agrobacterium tumefaciens tmr and tzs loci.the nucleotide sequence of a pseudomonas trans-zeatin producing gene (ptz) from the pck1 plasmid of pseudomonas syringae pv. savastanoi strain 1006 has been determined. this gene confers upon e. coli the ability to synthesize and secrete several cytokinins including trans-zeatin, iso-pentenyladenine and their respective n9-ribosyl derivatives. sequence analysis indicates an open reading frame encoding a protein of 234 amino acids with a molecular weight of 26,816. significant sequence homology i ...19863515320
release of cell-free ice nuclei by erwinia herbicola.several ice-nucleating bacterial strains, including erwinia herbicola, pseudomonas fluorescens, and pseudomonas syringae isolates, were examined for their ability to shed ice nuclei into the growth medium. only e. herbicola isolates shed cell-free ice nuclei active at -2 to -10 degrees c. these cell-free nuclei exhibited a freezing spectrum similar to that of ice nuclei found on whole cells, both above and below -5 degrees c. partially purified cell-free nuclei were examined by density gradient ...19863525514
mechanism of action of pseudomonas syringae phytotoxin, syringomycin. interaction with the plasma membrane of wild-type and respiratory-deficient strains of saccharomyces cerevisiae.the effects of the phytotoxin, syringomycin, produced by pseudomonas syringae pv. syringae, were examined on cells of a wild-type and a respiratory-deficient (rho0) mutant of saccharomyces cerevisiae. the growth of both strains in liquid culture was inhibited by 0.5 micrograms syringomycin per ml and higher. uptake rates of tetraphenylphosphonium and dimethyloxazolidine ions in cell suspensions of both strains increased when 1.5 micrograms per ml syringomycin was added. these responses were kine ...19863530326
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
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
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
production of fosfomycin (phosphonomycin) by pseudomonas syringae. 19863759643
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 ...19863774551
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
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 ...19853873905
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 ...19853900043
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 ...19863957873
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