Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| bacteriophage phi 6 envelope elucidated by chemical cross-linking, immunodetection, and cryoelectron microscopy. | bacteriophage phi 6 is an enveloped dsrna virus which infects the plant pathogenic pseudomonas syringae bacterium. using low dose cryoelectron microscopy we show that the nucleocapsid, spikeless virion, and intact virion have radii of 29, 35, and 43 nm, respectively. thus, the membrane is 6 nm thick and the surface spikes of the receptor binding protein p3 extend 8 nm from the membrane surface. cross-linking, immunological, and complementation evidence suggest that the spikes are formed of multi ... | 1992 | 1519356 |
| epiphytic populations of pseudomonas syringae on barley. | the epiphytic populations of pseudomonas syringae were monitored on 23 barley entries planted in the field in four replications during the summer of 1986, and on six selected entries during the summer of 1987, from the second-leaf stage until senescence. populations were initially low (0-3 log colony-forming units (cfu) per leaf) in all but one entry; they generally increased throughout the season, and at the end they reached 3-7 log cfu/leaf. significant differences among the average epiphytic ... | 1992 | 1521185 |
| origin, structure, and regulation of argk, encoding the phaseolotoxin-resistant ornithine carbamoyltransferase in pseudomonas syringae pv. phaseolicola, and functional expression of argk in transgenic tobacco. | pseudomonas syringae pv. phaseolicola produces the tripeptide n delta(n'-sulfo-diaminophosphinyl)-ornithylalanyl-homoarginin e (phaseolotoxin), which functions as a chlorosis-inducing toxin in the bean halo blight disease by inhibiting ornithine carbamoyltransferase (oct). the bacterium possesses duplicate oct genes, one of which, argk, encodes a toxin-resistant enzyme (roct) and imparts resistance to phaseolotoxin. we sequenced the argk gene from strain nps3121, defined its promoter region, ana ... | 1992 | 1522066 |
| dna homology between siderophore genes from fluorescent pseudomonads. | many species of pseudomonads produce fluorescent siderophores involved in iron uptake. we have investigated the dna homology between the siderophore synthesis genes of an opportunist animal pathogen, pseudomonas aeruginosa, and three plant-associated species pseudomonas syringae, pseudomonas putida and pseudomonas sp. b10. there is extensive homology between the dna from the different species, consistent with the suggestion that the different siderophore synthesis genes have evolved from the sam ... | 1992 | 1532617 |
| the cloned avirulence gene avrpto induces disease resistance in tomato cultivars containing the pto resistance gene. | resistance of tomato plants to the bacterial pathogen pseudomonas syringae pv. tomato race 0 is controlled by the locus pto. a bacterial avirulence gene was cloned by constructing a cosmid library from an avirulent p. syringae pv. tomato race, conjugating the recombinants into a strain of p. syringae pv. maculicola virulent on a tomato cultivar containing pto, and screening for those clones that converted the normally virulent phenotype to avirulence. the cloned gene, designated avrpto, reduced ... | 1992 | 1537802 |
| organization and environmental regulation of the pseudomonas syringae pv. syringae 61 hrp cluster. | the ability of pseudomonas syringae pv. syringae 61 to elicit the hypersensitive response in nonhost plant species has been linked to a cluster of hrp/hrm genes whose expression appears to be environmentally regulated. to understand the genetic organization of this hrp/hrm gene cluster and its expression during the interaction with nonhost plant species better, we constructed a set of chromosomal hrp-uida fusions in p. syringae pv. syringae 61 by tn5-gusa1 mutagenesis of the cloned hrp/hrm gene ... | 1992 | 1548225 |
| physical and functional characterization of the gene cluster encoding the polyketide phytotoxin coronatine in pseudomonas syringae pv. glycinea. | pseudomonas syringae pv. glycinea pg4180 produces the polyketide phytotoxin coronatine. the coronatine synthesis genes in pg4180 were previously shown to reside on a 90-kb plasmid designated p4180a. in the present study, clones containing a 34-kb region of p4180a were saturated with tn5, and 71 unique mutations were recombined into p4180a by marker exchange. the effect of each mutation on coronatine synthesis was determined by analyzing the organic acids produced by the mutants by reverse-phase ... | 1992 | 1548231 |
| biolistic transformation of prokaryotes: factors that affect biolistic transformation of very small cells. | five bacterial species were transformed using particle gun-technology. no pretreatment of cells was necessary. physical conditions (helium pressure, target cell distance and gap distance) and biological conditions (cell growth phase, osmoticum concentration, and cell density) were optimized for biolistic transformation of escherichia coli and these conditions were then used to successfully transform agrobacterium tumefaciens, erwinia amylovora, erwinia stewartii and pseudomonas syringae pv. syri ... | 1992 | 1556553 |
| plant and environmental sensory signals control the expression of hrp genes in pseudomonas syringae pv. phaseolicola. | the hrp genes of pseudomonas syringae pv. phaseolicola control the development of primary disease symptoms in bean plants and the elicitation of the hypersensitive response in resistant plants. we examined the expression of the seven operons located in the 22-kb hrp cluster (l. g. rahme, m. n. mindrinos, and n. j. panopoulos, j. bacteriol. 173:575-586, 1991) in planta and in vitro under different physiological and nutritional conditions by using chromosomally located hrp::inaz reporter fusions. ... | 1992 | 1592805 |
| efficacy of burning, tillage, and biocides in controlling bacteria released at field sites and effects on indigenous bacteria and fungi. | decontamination treatments of burning and biocide application, alone and in combination with tillage, were evaluated for their ability to reduce populations of bacteria applied to the leaves of plants in field plots. in addition, the effects of these control methods on indigenous leaf and soil bacteria and fungi were assessed. field plots of bush beans (phaseolus vulgaris), sprayed with the bacterium pseudomonas syringae, pseudomonas fluorescens, or erwinia herbicola, received the following trea ... | 1992 | 1599240 |
| pathovar-specific requirement for the pseudomonas syringae lema gene in disease lesion formation. | the lema gene is conserved among strains and pathovars of pseudomonas syringae. in p. syringae pv. syringae b728a, a causal agent of bacterial brown spot disese of bean, the lema gene is required for lesion formation on leaves and pods. using lema-containing dna as a probe, we determined that 80 p. syringae pv. syringae strains isolated from bean leaves could be grouped into seven classes based on restriction fragment length polymorphism. marker exchange mutagenesis showed that the lema gene was ... | 1992 | 1622209 |
| evidence for a correlation between auxin production and host plant species among strains of pseudomonas syringae subsp. savastanoi. | auxin production by 131 strains of pseudomonas syringae subsp. savastanoi was investigated with the aim of looking for correlations among this characteristic and the origin of the strains, the types of symptoms, and the host plant. most of the p.syringae subsp. savastanoi strains, except those isolated from ash, produced auxin and harbored iaa genes. among ash strains, which were pathogenic only on ash, only 2 out of 33 were found to produce auxin and to harbor iaa genes. | 1992 | 1622252 |
| phytoalexin accumulation in arabidopsis thaliana during the hypersensitive reaction to pseudomonas syringae pv syringae. | inoculation of leaves of arabidopsis thaliana (l.) heynh. with the wheat pathogen, pseudomonas syringae pv syringae, resulted in the expression of the hypersensitive reaction and in phytoalexin accumulation. no phytoalexin accumulation was detected after infiltration of leaves with a mutant of p. s. syringae deficient in the ability to elicit a hypersensitive reaction; with the crucifer pathogen, xanthomonas campestris pv campestris; or with 10 millimolar potassium phosphate buffer (ph 6.9). phy ... | 1992 | 16668792 |
| a lipoxygenase from leaves of tomato (lycopersicon esculentum mill.) is induced in response to plant pathogenic pseudomonads. | lipoxygenase (lox) mrna, enzyme protein, and enzyme activity were found to be induced in leaves of tomato (lycopersicon esculentum mill. cv moneymaker) on inoculation with plant pathogenic bacteria. the rate of enzyme activity with linoleic or linolenic acid as substrate was approximately 10 times greater than that with arachidonic acid. optimum activity was at ph 7.0. in the incompatible interaction, which was associated with a hypersensitive reaction (hr), a single band with relative molecular ... | 1992 | 16668924 |
| the stimulation of ethylene synthesis in nicotiana tabacum leaves by the phytotoxin coronatine. | coronatine is a chlorosis-inducing toxin produced by the plant pathogen pseudomonas syringae pv atropurpurea. this bacterium is the causal agent of chocolate spot disease, in which brown lesions with chlorotic margins develop on the leaves of lolium multiflorum lam. among the many physiological changes to plants caused by coronatine is the stimulation of ethylene production from bean leaves. the ethyl-substituted side chain of coronatine is an analog of the ethylene precursor, 1-aminocyclopropan ... | 1992 | 16652950 |
| expression of a bacterial ice nucleation gene in plants. | we have introduced an ice nucleation gene (inaz) from pseudomonas syringae pv. syringae into nicotiana tabacum, a freezing-sensitive species, and solanum commersonii, a freezing-tolerant species. transformants of both species showed increased ice nucleation activity over untransformed controls. the concentration of ice nuclei detected at -10.5 degrees c in 15 different primary transformants of s. commersonii varied by over 1000-fold, and the most active transformant contained over 100 ice nuclei ... | 1992 | 16653190 |
| accumulation of copper and other metals by copper-resistant plant-pathogenic and saprophytic pseudomonads. | copper-resistant strains of pseudomonas syringae carrying the cop operon produce periplasmic copper-binding proteins, and this sequestration outside the cytoplasm has been proposed as a resistance mechanism. in this study, strain ps61 of p. syringae carrying the cloned cop operon accumulated more total cellular copper than without the operon. several other copper-resistant pseudomonads with homology to cop were isolated from plants, and these bacteria also accumulated copper. two highly resistan ... | 1992 | 16348627 |
| detection of a single genetically modified bacterial cell in soil by using charge coupled device-enhanced microscopy. | genes encoding bioluminescence from vibrio harveyi were cloned into pseudomonas syringae pv. phaseoli-cola, resulting in high levels of bioluminescence. after inoculation of sterile and nonsterile soil slurries with bioluminescent p. syringae, cells could not be identified by conventional light microscopy. however, when we used charge coupled device-enhanced microscopy, bioluminescent single cells were detected easily in dark fields despite masking by soil particulate matter, and in addition, th ... | 1992 | 16348749 |
| topical application of ice-nucleating-active bacteria decreases insect cold tolerance. | the majority of overwintering insects avoid lethal freezing by lowering the temperature at which ice spontaneously nucleates within their body fluids. we examined the effect of ice-nucleating-active bacteria on the cold-hardiness of the lady beetle, hippodamia convergens, a freeze-intolerant species that overwinters by supercooling to ca. -16 degrees c. topical application of the ice-nucleating-active bacteria pseudomonas syringae increased the supercooling point to temperatures as high as -3 de ... | 1992 | 16348764 |
| novel method for identifying bacterial mutants with reduced epiphytic fitness. | in order to identify novel traits involved in epiphytic colonization, a technique for the rapid identification of bacterial mutants with quantitatively different population sizes in a natural habitat based on measurements of ice nucleation activity was developed. the threshold freezing temperatures of leaves harboring different numbers of cells of ice nucleation-active pseudomonas syringae b728a differed substantially. while few leaves containing less than about 10 cells per g (fresh weight) fro ... | 1993 | 16348938 |
| characteristics of insertional mutants of pseudomonas syringae with reduced epiphytic fitness. | random tn5 mutagenesis was used to identify genes ir. pseudomonas syringae which contribute to epiphytic fitness. mutants were selected on the basis of deficiencies in epiphytic growth or survival on plants rather than deficiencies in predetermined phenotypes exhibited in culture. a sample freezing procedure was used to measure the population sizes of 5,300 mutants of p. syringae exposed to alternating wet and dry conditions on bean leaves in growth chambers. eighty-two mutants exhibited reduced ... | 1993 | 16348939 |
| effects of environmental and nutritional factors on production of the polyketide phytotoxin coronatine by pseudomonas syringae pv. glycinea. | pseudomonas syringae pv. glycinea pg4180 produces the polyketide phytotoxin coronatine. the effects of environmental, nutritional, and host factors on growth and coronatine production by pg4180 were examined by varying the components of a defined basal medium which contained the following nutrients per liter: glucose (10 g), nh(4)cl (1 g), mgso(4) . 7h(2)o (0.2 g), kh(2)po(4) (4.1 g), k(2)hpo(4) . 3h(2)o (3.6 g), and fecl(3) (2 mum). bacterial growth was recorded as dry weight, and coronatine pr ... | 1993 | 16348941 |
| similarity between copper resistance genes from xanthomonas campestris and pseudomonas syringae. | plasmid-borne copper resistance genes from copper-resistant strains of xanthomonas campestris pv. vesicatoria from california, florida, and oklahoma shared structural similarities. a strain of x. campestris pv. campestris also contained plasmid-borne copper resistance genes similar to the resistance genes from x. campestris pv. vesicatoria. furthermore, a region of the copper resistance genes from x. campestris pv. vesicatoria 07882 hybridized with copa, the first gene of the copper resistance o ... | 1993 | 16348942 |
| copper hypersensitivity and uptake in pseudomonas syringae containing cloned components of the copper resistance operon. | copper resistance in pseudomonas syringae carrying the copabcd operon is associated with accumulation of copper in the periplasm and outer membrane, apparently as a function of the copper-binding activities of the copabc gene products. however, no specific function for copd has been determined. in this study, p. syringae cells containing copcd or copbcd cloned behind the lac promoter were hypersensitive to copper. an increased accumulation of copper was measured in cells containing several combi ... | 1993 | 16348944 |
| invasion and exclusion among coexisting pseudomonas syringae strains on leaves. | the invasion and exclusion abilities of coexisting pseudomonas syringae strains were quantified on leaves. twenty-nine p. syringae strains were inoculated onto plants in 107 pairwise combinations. all pairs were duplicated so that each strain was inoculated both first as an antagonist strain (day 0) and second as a challenge strain (day 3). the population size of each strain in a mixture was quantified on day 6 following incubation under moist conditions. for p. syringae strains, the presence of ... | 1993 | 16349074 |
| an arabidopsis thaliana lipoxygenase gene can be induced by pathogens, abscisic acid, and methyl jasmonate. | we isolated and characterized a 2.8-kb, full-length, arabidopsis thaliana cdna clone encoding a lipoxygenase. dna sequence analysis showed that the deduced amino acid sequence of the arabidopsis protein is 72 to 78% similar to that of legume seed lipoxygenases. dna blot analysis indicated that arabidopsis contains a single gene, lox1, with appreciable homology to the cdna clone. rna blot analysis showed that the lox1 gene is expressed in arabidopsis leaves, roots, inflorescences, and young seedl ... | 1993 | 7506426 |
| dna sequence and transcriptional analysis of the tbla gene required for tabtoxin biosynthesis by pseudomonas syringae. | the tbla gene of pseudomonas syringae is required for tabtoxin biosynthesis and is under the control of a regulatory gene, lema. we have determined the nucleotide sequence of the tbla gene and identified the 5' end of the tbla gene transcript. the sequence of the tbla gene was identified to that of the recently reported open reading frame 1 gene of the taba region of the br2 chromosome. the open reading frame of the tbla gene potentially encodes a protein of 231 amino acids. mrna from the tbla g ... | 1993 | 7679566 |
| use of charge-coupled device (ccd) image-enhancement for rapid screening and monitoring of prokaryotic promoter expression. | charge-coupled device (ccd) image-enhancement was used for rapid screening of genomic libraries and allowed selection of promoters with differing characteristics. in addition, both the ccd and luminometry were used to monitor and characterize the expression from two pseudomonas syringae pv. phaseolicola promoters. the same pattern of gene expression was indicated by the two methods but the ccd enabled the rapid non-destructive in situ monitoring of a microbial population, over a prolonged period ... | 1993 | 7763449 |
| map-based cloning of a protein kinase gene conferring disease resistance in tomato. | the pto gene in tomato confers resistance to races of pseudomonas syringae pv. tomato that carry the avirulence gene avrpto. a yeast artificial chromosome clone that spans the pto region was identified and used to probe a leaf complementary dna (cdna) library. a cdna clone was isolated that represents a gene family, at least six members of which genetically cosegregate with pto. when susceptible tomato plants were transformed with a cdna from this family, they were resistant to the pathogen. ana ... | 1993 | 7902614 |
| dna sequence variation and phylogenetic relationships among strains of pseudomonas syringae pv. syringae inferred from restriction site maps and restriction fragment length polymorphism. | we evaluated the restriction fragment length polymorphism of genomic dna among 53 strains of the phytopathogenic bacterium pseudomonas syringae pv. syringae. twenty-nine strains were isolated from beans, and the rest were isolated from 11 other hosts. southern blots of dna digested with ecori or hindiii were hybridized to two random probes from a cosmid library of p. syringae pv. syringae and a hrp (hypersensitive reaction and pathogenicity) cluster cloned from p. syringae pv. syringae. the size ... | 1993 | 7904440 |
| molecular characterization of field isolates of pseudomonas syringae pv. glycinea differing in coronatine production. | coronatine-producing and non-producing strains of pseudomonas syringae pv. glycinea have been examined. we found a connection between copper resistance and synthesis of coronatine. published data implied that these properties may be encoded on different plasmids. production of coronatine and copper resistance were also found to be correlated for pv. glycinea in 19 field-isolates from leaf spots of plants in a soybean field and in 28 strains of a bacterial culture collection. genomic diversity wi ... | 1993 | 8105024 |
| changes in cultivar-specificity toward pea can result from transfer of plasmid rp4 and other incompatibility group p1 replicons to pseudomonas syringae pv. pisi. | transfer of rp4 and related replicons belonging to the escherichia coli incompatibility group p (pseudomonas aeruginosa incp1) to races 2 and 6 of p. syringae pv. pisi was associated with the creation of two types of transconjugant, one resembling the parental race and the other showing an altered cultivar-specificity towards pea. the latter, irrespective of the parental race, exhibited a novel pattern of interaction with pea that corresponded to race 4; consequently such transconjugants were te ... | 1993 | 8126435 |
| an inducible nadp(+)-dependent d-phenylserine dehydrogenase from pseudomonas syringae nk-15: purification and biochemical characterization. | an inducible nadp(+)-dependent d-phenylserine dehydrogenase [ec 1.1.1.-], which catalyzes the oxidation of the hydroxyl group of d-threo-beta-phenylserine, was purified to homogeneity from a crude extract of pseudomonas syringae nk-15 isolated from soil. the enzyme consisted of two subunits identical in molecular weight (about 31,000). in addition to d-threo-beta-phenylserine, it utilized d-threo-beta-thienylserine, d-threo-beta-hydroxynorvaline, and d-threonine as substrates but was inert towar ... | 1993 | 8138554 |
| the cloning and characterization of phage promoters, directing high expression of luciferase in pseudomonas syringae pv. phaseolicola, allowing single cell and microcolony detection. | regions of dna containing promoter sequences from a pseudomonas syringae pv. phaseolicola-specific phage (phi 11p) were identified by shotgun cloning into a broad-host-range promoter-probe vector (pqf70). when used in conjunction with the luciferase reporter genes, one of these dna fragments, 19h, directed gene expression at a level which enabled the subsequent light output (bioluminescence) of single cells of p. syringae pv. phaseolicola to be detected and visualized using a charge-coupled devi ... | 1993 | 8162227 |
| homology between a genetic locus (mdoa) involved in the osmoregulated biosynthesis of periplasmic glucans in escherichia coli and a genetic locus (hrpm) controlling pathogenicity of pseudomonas syringae. | membrane-derived oligosaccharides (mdo) of escherichia coli are representative members of a family of glucans found in the periplasmic space of gram-negative bacteria. the two genes forming the mdogh operon are necessary for the synthesis of mdo. the nucleotide sequence (4759 bp) and the transcriptional start of this operon were determined. both gene products were further characterized by gene fusion analysis. mdog is a 56 kda periplasmic protein whose function remains to be determined. mdoh, wh ... | 1993 | 7934824 |
| yeast genes involved in growth inhibition by pseudomonas syringae pv. syringae syringomycin family lipodepsipeptides. | saccharomyces cerevisiae genes encoding functions necessary for inhibition by the pseudomonas syringae pv. syringae cyclic lipodepsipeptide, syringomycin-e, were identified by mutant analyses. syringomycin-e-resistant mutants were isolated, shown to contain single recessive mutations, and divided into eight gene complementation groups. representative strains from five groups were resistant to nystatin, and deficient in the plasma membrane lipid, ergosterol. all of the mutant strains were resista ... | 1993 | 8288110 |
| high-level expression of ice nuclei in a pseudomonas syringae strain is induced by nutrient limitation and low temperature. | attempts were made to maximize the expression of ice nuclei in pseudomonas syringae t1 isolated from a tomato leaf. nutritional starvation for nitrogen, phosphorous, sulfur, or iron but not carbon at 32 degrees c, coupled to a shift to 14 to 18 degrees c, led to the rapid induction of type 1 ice nuclei (i.e., ice nuclei active at temperatures warmer than -5 degrees c). induction was most pronounced in stationary-phase cells that were grown with sorbitol as the carbon source and cooled rapidly, a ... | 1993 | 8320222 |
| somatic antigens of pseudomonads: structure of the o-specific polysaccharide of pseudomonas syringae pv. tomato 140(r). | 1993 | 8324762 | |
| pseudomonas syringae pv. syringae harpinpss: a protein that is secreted via the hrp pathway and elicits the hypersensitive response in plants. | the ability of p. syringae to elicit the hypersensitive response in nonhost plants or pathogenesis in hosts is controlled by hrp genes. the p. syringae pv. syringae 61 hrpz gene encodes harpinpss, a 34.7 kd extracellular protein that elicits hypersensitive necrosis in tobacco and other plants. harpinpss is heat stable, glycine rich, dissimilar in amino acid sequence to any known protein, produced only in apoplastic fluid-mimicking minimal media, and secreted in a hrph-dependent manner. the carbo ... | 1993 | 8324821 |
| multiple copies of a dna sequence from pseudomonas syringae pathovar phaseolicola abolish thermoregulation of phaseolotoxin production. | phaseolotoxin, a phytotoxin of pseudomonas syringae pv. phaseolicola, is produced at 18 degrees c but not at 28 degrees c. here we report that a fragment (24.4 kb) cloned from the wild-type strain, which does not harbour a gene(s) involved in phaseolotoxin biosynthesis, abolishes this thermoregulation in the wild type and suppresses a tox- mutant at both temperatures. a subclone harbouring a 485 bp fragment contains motifs that are characteristic of dna-binding sites. in mobility shift assays we ... | 1993 | 8326870 |
| characterization of chromosomal homologs of the plasmid-borne copper resistance operon of pseudomonas syringae. | copper-resistant and copper-sensitive strains of pseudomonas syringae, as well as many other pseudomonads, contain chromosomal dna homologous to the plasmid-borne copper resistance operon (copabcd). cop homologs were cloned from the chromosome of p. syringae pv. tomato pt12.2, which had an elevated level of resistance to copper compared with typical copper-sensitive strains of other p. syringae pathovars and showed an unusually high frequency of spontaneous mutation to high levels of copper resi ... | 1993 | 8331076 |
| molecular analysis of avirulence gene avrrpt2 and identification of a putative regulatory sequence common to all known pseudomonas syringae avirulence genes. | the avrrpt2 locus from pseudomonas syringae pv. tomato causes virulent strains of p. syringae to be avirulent on some, but not all, lines of arabidopsis thaliana and glycine max (soybean). we determined the dna sequence of the avrrpt2 locus and identified the avrrpt2 gene as a 768-bp open reading frame encoding a putative 28.2-kda protein. deletion analysis and transcription studies provided further evidence that this open reading frame encodes avrrpt2. we found that the avrrpt2 gene also has av ... | 1993 | 8335641 |
| the 73-kb piaa plasmid increases competitive fitness of pseudomonas syringae subspecies savastanoi in oleander. | pseudomonas syringae subsp. savastanoi causes tumors on olive and oleander by producing the plant growth regulators indoleacetic acid (iaa) and cytokinins following infection of the plant. the contribution of iaa production to the ability of p. syringae subsp. savastanoi to grow and survive in oleander leaf tissue was studied. bacterial strains differing only with respect to iaa production were characterized. growth and survival of wild-type and two mutant strains of p. syringae subsp. savastano ... | 1993 | 8364801 |
| characterization of the promoter of avirulence gene d from pseudomonas syringae pv. tomato. | the avirulence gene d (avrd) from pseudomonas syringae pv. tomato comprises the first open reading frame (orf) of a putative operon consisting of at least five tandem orfs. the promoter of the avrd operon was localized to a 150-bp dna fragment occurring 5' to the avrd gene by using the tn7-lux and gus reporter systems. the avrd promoter in p. syringae pv. tomato and p. syringae pv. glycinea was poorly expressed when bacteria were grown in complex culture media but was activated during bacterial ... | 1993 | 8376338 |
| nucleotide sequence analysis of a transposon (tn5393) carrying streptomycin resistance genes in erwinia amylovora and other gram-negative bacteria. | a class ii tn3-type transposable element, designated tn5393 and located on plasmid pea34 from streptomycin-resistant strain ca11 of erwinia amylovora, was identified by its ability to move from pea34 to different sites in plasmids pgem3zf(+) and pucd800. nucleotide sequence analysis reveals that tn5393 consists of 6,705 bp with 81-bp terminal inverted repeats and generates 5-bp duplications of the target dna following insertion. tn5393 contains open reading frames that encode a putative transpos ... | 1993 | 8380801 |
| characterization of an insertion sequence (is53) located within is51 on the iaa-containing plasmid of pseudomonas syringae pv. savastanoi. | a 2568-base pair (bp) insertion sequence (is53) was cloned from the iaa-containing plasmid piaa2 of pseudomonas syringae subsp. savastanoi. is53 is located downstream from the iaa operon and is inserted into is51, a previously described element on piaa2. is53 causes an 8-bp target duplication and has nearly perfect terminal inverted repeats of 27 bp. several degenerate copies of the inverted repeats are located internal, and in direct orientation to the terminal inverted repeats. a putative tran ... | 1993 | 8385786 |
| arabidopsis mutations at the rps2 locus result in loss of resistance to pseudomonas syringae strains expressing the avirulence gene avrrpt2. | we isolated and characterized two arabidopsis thaliana mutants that fail to mount a hypersensitive defense response (hr) when infiltrated with phytopathogenic pseudomonas strains carrying the avirulence (avr) gene avrrpt2 but still mount an hr when infiltrated with strains carrying other avr genes. one of these mutants was isolated using a method we developed that enriches for arabidopsis seedlings that survive vacuum-infiltration with a bacterial strain carrying an avr gene. genetic analysis sh ... | 1993 | 8400373 |
| spatial and temporal accumulation of defense gene transcripts in bean (phaseolus vulgaris) leaves in relation to bacteria-induced hypersensitive cell death. | primary leaves of 7- to 9-day-old red mexican bean plants were inoculated with virulent or avirulent isolates of pseudomonas syringae pv. phaseolicola, or saprophytic p. fluorescens either by vacuum infiltration of the whole leaf lamina, or by syringe-inoculation of selected leaf panels. in the incompatible combination, resistance was associated with a hypersensitive response (hr). syringe-inoculated leaves were sampled in three zones: zone 1, the inoculated leaf area; zone 2, the surrounding 0. ... | 1993 | 8400375 |
| characterization of the pseudomonas syringae pv. syringae 61 hrpj and hrpi genes: homology of hrpi to a superfamily of proteins associated with protein translocation. | the pseudomonas syringae pv. syringae 61 hrpj and hrpi genes were sequenced and found to encode predicted proteins of 37,710 da and 76,490 da, respectively. the products of these genes were confirmed by t7 polymerase-dependent expression and sodium dodecyl sulfate-polyacrylamide gel analysis. hrpi belongs to a superfamily of proteins represented by yersinia pestis lcrd. | 1993 | 8400380 |
| rps2, an arabidopsis disease resistance locus specifying recognition of pseudomonas syringae strains expressing the avirulence gene avrrpt2. | a molecular genetic approach was used to identify and characterize plant genes that control bacterial disease resistance in arabidopsis. a screen for mutants with altered resistance to the bacterial pathogen pseudomonas syringae pv. tomato (pst) expressing the avirulence gene avrrpt2 resulted in the isolation of four susceptible rps (resistance to p. syringae) mutants. the rps mutants lost resistance specifically to bacterial strains expressing avrrpt2 as they retained resistance to pst strains ... | 1993 | 8400869 |
| genetic organization of a cluster of genes involved in the production of phaseolotoxin, a toxin produced by pseudomonas syringae pv. phaseolicola. | phaseolotoxin [n delta(n'-sulfo-diaminophosphinyl)-ornithyl-alanyl- homoarginine] produced by pseudomonas syringae pv. phaseolicola, the bean halo blight pathogen, is a potent inhibitor of ornithine carbamoyltransferase (oct). inhibition of oct in infected plants leads to chlorosis and growth inhibition. a genomic cosmid clone, phk120, containing a 25-kb fragment of dna from a wild-type strain of p. syringae pv. phaseolicola restores toxin production in tox- mutants. tn5 mutagenesis of phk120 an ... | 1993 | 8407821 |
| erwinia stewartii wtsa, a positive regulator of pathogenicity gene expression, is similar to pseudomonas syringae pv. phaseolicola hrps. | erwinia stewartii contains a large cluster of wts genes that are required by this bacterium for pathogenicity on corn plants. three complementation groups within the right half of this cluster, wtsa, wtsc, and wtsb, were previously identified. in this study, wtsa was found to be a positive activator of wtsb::lacz expression. the wtsa locus was sequenced and a single open reading frame is present within the wtsa locus, which has the capacity to encode a 323 amino acid polypeptide. a corresponding ... | 1993 | 8412697 |
| nucleotide sequences of the trpi, trpb, and trpa genes of pseudomonas syringae: positive control unique to fluorescent pseudomonads. | a 904-bp probe from pseudomonas aeruginosa was used to identify the trpb, trpa and trpi genes of pseudomonas syringae. transcription initiation at the p. syringae trpba promoter in vitro was activated by the p. aeruginosa trpi protein in the presence of indoleglycerol phosphate. thus, trpb and trpa are regulated positively in three species of fluorescent pseudomonads, p. aeruginosa, p. putida, and p. syringae, but in no other eubacteria so far investigated [crawford, annu. rev. microbiol. 43 (19 ... | 1993 | 8423001 |
| effect of phenotypic plasticity on epiphytic survival and colonization by pseudomonas syringae. | the bacterial epiphyte pseudomonas syringae mf714r was cultured on agar or in broth or collected from colonized leaves; it was then inoculated onto greenhouse-grown bean plants incubated in a growth chamber at low relative humidity or in the field or onto field-grown bean plants. cells cultured in liquid medium survived the least well after inoculation of leaf surfaces under all conditions. cells cultured in solid medium exhibited the highest percent survival and desiccation tolerance in the gro ... | 1993 | 8434910 |
| role of copper resistance in competitive survival of pseudomonas fluorescens in soil. | a copper-resistant strain (09906) of pseudomonas fluorescens that was isolated from a citrus grove soil is being investigated as a biological control agent for phytophthora root rot. since citrus grove soils in california are often contaminated with copper from many years of copper fungicide applications, the role of copper resistance in survival of strain 09906 was investigated. three copper-sensitive tn5 mutants were obtained with insertions in different chromosomal dna regions. these insertio ... | 1993 | 8434924 |
| survival differences among freeze-dried genetically engineered and wild-type bacteria. | because the death mechanisms of freeze-dried and air-dried bacteria are thought to be similar, freeze-drying was used to investigate the survival differences between potentially airborne genetically engineered microorganisms and their wild types. to this end, engineered strains of escherichia coli and pseudomonas syringae were freeze-dried and exposed to air, visible light, or both. the death rates of all engineered strains were significantly higher than those of their parental strains. light an ... | 1993 | 8434925 |
| a two-component regulatory system required for copper-inducible expression of the copper resistance operon of pseudomonas syringae. | specific induction of the copper resistance operon (cop) promoter from pseudomonas syringae was measured by beta-galactosidase production from a cop promoter-lacz fusion. induction of the cop promoter in p. syringae pv. syringae required trans-acting factors from copper resistance plasmid ppt23d, from which cop was originally cloned. tn5 mutagenesis of ppt23d was used to localize two complementation groups immediately downstream from copabcd. cloning and sequencing of the dna in this region reve ... | 1993 | 8449873 |
| structural studies of the enveloped dsrna bacteriophage phi 6 of pseudomonas syringae by raman spectroscopy. i. the virion and its membrane envelope. | we report and interpret the first raman spectrum of a double-stranded rna virus containing a membrane envelope. spectra of the native bacteriophage phi 6 and of its isolated host-attachment (spike) protein and phospholipid-free core assembly were collected from aqueous solutions over a wide range of temperature. comparison of the vibrational spectra by digital difference methods permits the following structural conclusions regarding molecular constituents of the fully assembled virion. (1) the d ... | 1993 | 8464060 |
| structural studies of the enveloped dsrna bacteriophage phi 6 of pseudomonas syringae by raman spectroscopy. ii. nucleocapsid structure and thermostability of the virion, nucleocapsid and polymerase complex. | structures and thermostabilities of the double-stranded (ds) rna bacteriophage phi 6 and of its isolated nucleocapsid-polymerase complex (nucleocapsid core) and dsrna components have been investigated by raman spectroscopy. the spectra show that proteins of the phi 6 virion are collectively deficient in beta-sheet secondary structure. in particular, the major protein (p8) of the outer spherical shell of the phi 6 nucleocapsid exhibits a secondary structure dominated largely by alpha-helix and ir ... | 1993 | 8464061 |
| ecological and genetic analysis of copper and streptomycin resistance in pseudomonas syringae pv. syringae. | strains of pseudomonas syringae pv. syringae resistant to copper, streptomycin, or both compounds were recovered from symptomless and diseased tissue of four woody hosts in three nurseries in oklahoma. in strains resistant to copper and streptomycin (cur smr), resistance to both compounds was cotransferred with a single plasmid which was either 68, 190, or 220 kilobase pairs (kb). all cus smr strains contained a 68-kb conjugative plasmid. cur sms strains contained one plasmid which varied in siz ... | 1993 | 8476279 |
| dynamics, spread, and persistence of a single genotype of pseudomonas syringae relative to those of its conspecifics on populations of snap bean leaflets. | a rifampin-resistant strain of pseudomonas syringae (r10) was introduced onto bean plants grown in field plots to examine the processes of growth, spread, and survival of a single genotype relative to the dynamics of its conspecifics on populations of individual leaflets. r10 was applied to four plots (400, 200, 100, and 50 m2), each of which was centered in a quadrant of a bean field (90 by 90 m). population sizes of the species p. syringae and of r10 were determined on each of 25 individual le ... | 1993 | 8476284 |
| genetic characterization of the pto locus of tomato: semi-dominance and cosegregation of resistance to pseudomonas syringae pathovar tomato and sensitivity to the insecticide fenthion. | the pto locus governs resistance to bacterial speck disease in tomato caused by race 0 strains of pseudomonas syringae pathovar tomato (pst). large populations segregating for the pto locus were generated and genetically characterized. analysis of the locus has revealed that pto acts in a semi-dominant manner and cosegegrates with sensitivity to an organophosphorous insecticide, fenthion, suggesting that pto may be a complex locus responsible for both phenotypes. we have redefined its map positi ... | 1993 | 8510645 |
| molecular characterization and hrp dependence of the avirulence gene avrpto from pseudomonas syringae pv. tomato [corrected]. | the avrpto avirulence gene from pseudomonas syringae pv. tomato (pst) race 0 governs race-specific resistance to bacterial speck disease in tomato cultivars containing the pto resistance gene. the avrpto gene encodes 0.7 and 0.75 kb mrnas whose predicted translation product is a mostly hydrophilic 164 amino acid protein of 18.3 kd a that reveals no homology to protein sequences in genbank or embl databases. highest expression of avrpto in cell culture is observed in minimal media containing suga ... | 1993 | 8510663 |
| expression of the alpha-thionin gene from barley in tobacco confers enhanced resistance to bacterial pathogens. | thionins are cysteine-rich, 5 kda polypeptides which are toxic to plant pathogens in vitro. expression of the gene encoding alpha-thionin from barley endosperm, under the 35s promoter from cauliflower mosaic virus, conferred to transgenic tobacco enhanced resistance to the bacterial plant pathogens pseudomonas syringae pv. tabaci 153 and p. syringae pv. syringae. the barley alpha-thionin gene, which has two introns, was correctly spliced in tobacco. the alpha-thionin in transgenic plants had the ... | 1993 | 8220454 |
| arabidopsis mutants compromised for the control of cellular damage during pathogenesis and aging. | mutants of arabidopsis thaliana which exhibit accelerated cell death in response to pathogens were isolated and characterized to gain insight into how symptom severity and disease resistance are modulated. this paper describes mutants that fall into one of two complementation groups that were identified. a novel feature of these mutants is that they are unable to control the rate and extent of cell death after exposure to a variety of stimuli that induce senescence responses. thus, accelerated c ... | 1993 | 8220484 |
| characterization of the genes controlling the biosynthesis of the polyketide phytotoxin coronatine including conjugation between coronafacic and coronamic acid. | pseudomonas syringae pv. glycinea pg4180 produces a chlorosis-inducing phytotoxin, coronatine (cor), which consists of a polyketide component, coronafacic acid (cfa), which is coupled via amide bond formation to coronamic acid (cma), an ethylcyelopropyl amino acid (aa) derived from isoleucine. p. syringae pv. syringae strains ps51 and ps61, which do not synthesize coronafacoyl compounds (conjugates between cfa and aa), acquired the ability to produce cfa and cor when transformed with p4180a, a 9 ... | 1993 | 8224892 |
| kinetics of appearance and disappearance of classes of bacterial ice nuclei support an aggregation model for ice nucleus assembly. | the kinetics of appearance and disappearance of three classes of ice nuclei in pseudomonas syringae was investigated under conditions where high-level expression of the ice nucleation phenotype was obtained. the appearance of types 1, 2, and 3 ice nuclei, catalyzing nucleation at -2 to -5, -5 to -7, and -7 to -10 degrees c, respectively, was investigated during low-temperature induction in wild-type strains and in a unique, detergent-sensitive mutant that contained no type 3 ice nuclei when grow ... | 1993 | 8226668 |
| dodecylguanidine monoacetate (dodine) causes severe membrane damage in pseudomonas syringae above the critical micelle concentration. | the release of k+ from pseudomonas syringae cells treated with dodecylguanidine monoacetate (dodine) was followed with a k(+)-selective glass electrode. treatment of the cells with 5-15 mumol/l dodine resulted in low levels of k+ release, but higher surfactant concentrations caused extensive and rapid k+ efflux. dodine concentrations that caused high k+ release also induced significant leakage of inorganic phosphate. the addition of 5-10 mumol/l dodine also caused an increase in the rate of oxyg ... | 1993 | 8229668 |
| occurrence of antimicrobial activities of bacteria from soybean leaf spots. | bacteria were isolated from leaf spots of field grown soybeans during two growing seasons. the leaf spots yielded up to 4 different species and a total population size of about 10(7)-10(8) bacteria/cm2. the majority of the 192 isolates belonged to the species pseudomonas syringae pv. glycinea (55%), causing leaf spots of bacterial blight on soybeans, and erwinia herbicola (22%). the remaining isolates included bacteria from other genera, but occurred occasionally. the determination of biological ... | 1993 | 8229675 |
| syrd is required for syringomycin production by pseudomonas syringae pathovar syringae and is related to a family of atp-binding secretion proteins. | the syrd gene of pseudomonas syringae pathovar syringae strain b301d-r was characterized and sequenced. the syrd open reading frame is 1695 bp long and encodes a predicted protein, syrd, of approximately 63 kda. database searches revealed that syrd shares a high degree of similarity with the atp-binding cassette (abc) superfamily of transporter proteins which are responsible for specific nutrient uptake and for secretion of certain cellular products in prokaryotes, and for multiple drug resistan ... | 1993 | 8231810 |
| leucine aminopeptidase: an inducible component of the defense response in lycopersicon esculentum (tomato). | a leucine aminopeptidase (ec 3.4.11.1) cdna clone (dr57) that was induced in response to pseudomonas syringae pv. tomato (p.s. tomato) infection was isolated using a subtractive hybridization-enriched cdna probe. genomic dna blot analysis showed that the tomato genome had two leucine aminopeptidase genes. the levels of dr57 mrnas after p.s. tomato infection and mechanical wounding were determined in two inbred tomato lines that exhibit susceptibility and resistance to p.s. tomato. dr57 mrnas wer ... | 1993 | 8234334 |
| hrpi of erwinia amylovora functions in secretion of harpin and is a member of a new protein family. | hrpi, a 78-kda protein, functions in the secretion of harpin, a proteinaceous elicitor of the hypersensitive response from erwinia amylovora. the predicted amino acid sequence of hrpi is remarkably similar to that of lcrd of yersinia species, the first member of a recently described protein family. other proteins of the family are mixa from shigella flexneri, inva from salmonella typhimurium, flha from caulobacter crescentus, hrpi from pseudomonas syringae pv. syringae, hrpo from pseudomonas sol ... | 1993 | 8253684 |
| nucleotide sequence and properties of the hrma locus associated with the pseudomonas syringae pv. syringae 61 hrp gene cluster. | the hrma locus, isolated from pseudomonas syringae pv. syringae 61, is essential for phenotypic expression of the p. s. pv. syringae 61 hrp cluster in escherichia coli strains and enables bacteria carrying the hrp/hrm gene cluster to elicit the hypersensitive response (hr) associated with plant disease resistance. the phenotype of p. s. pv syringae 61 hrma mutants (pathogenicity+, delayed hr) was distinct from that of hrp mutants. the locus was localized to a 3.6-kb bamh1-ecor1 fragment whose nu ... | 1993 | 8274770 |
| recognition of the avirulence gene avrb from pseudomonas syringae pv. glycinea by arabidopsis thaliana. | the response of arabidopsis thaliana land race columbia to the bacterial pathogen pseudomonas syringae pv. maculicola 4326 harboring cloned avirulence genes avrb and avrc from p. syringae pv. glycinea and avra and avrd from p. syringae pv. tomato was examined. only avrb was recognized by columbia, as evidenced by attenuation of disease symptoms, slower bacterial multiplication in planta, and differentially greater induction of mrna for several defense-related genes. this contrasts with two a. th ... | 1993 | 8274772 |
| pathological and molecular characterizations of alfalfa interactions with compatible and incompatible bacteria, xanthomonas campestris pv. alfalfae and pseudomonas syringae pv. pisi. | we report on the interactions of alfalfa with xanthomonas campestris pv. alfalfae and pseudomonas syringae pv. pisi. a hypersensitive response was observed when leaves were infiltrated with p. s. pv. pisi, which remained strictly limited to the injected zone. the compatible interaction with x. c. pv. alfalfae was characterized by water-soaking symptoms and the spreading of the bacterium into the leaf blade. analyses of transcript accumulation were conducted with cdnas encoding enzymes involved i ... | 1993 | 8274775 |
| identification of a disease resistance locus in arabidopsis that is functionally homologous to the rpg1 locus of soybean. | a new disease resistance locus in arabidopsis, rps3, was identified using a previously cloned avirulence gene from a non-arabidopsis pathogen. the avrb avirulence gene from the soybean pathogen pseudomonas syringae pv. glycinea was transferred into a p. syringae pv. tomato strain that is virulent on arabidopsis, and conversion to avirulence was assayed on arabidopsis plants. the avrb gene had avirulence activity on most, but not all, arabidopsis ecotypes. of 53 ecotypes examined, 45 were resista ... | 1993 | 8275100 |
| purification of aspartate transcarbamoylase from pseudomonas syringae. | the aspartate transcarbamoylase (atcase) from pseudomonas syringae has been purified. the purified enzyme was shown by sds-page to give two bands. unambiguous results from n-terminal sequencing suggested that each band represented a homogeneous polypeptide. the m(r) (relative molecular mass) of the polypeptides was estimated to be 47 kda and 34 kda. the m(r) of the holoenzyme determined by gel filtration and electrophoretic migration in polyacrylamide gradient gels under non-denaturing condition ... | 1993 | 8282189 |
| generalized induction of defense responses in bean is not correlated with the induction of the hypersensitive reaction. | transcripts for phenylalanine ammonia-lyase, chalcone synthase, chalcone isomerase, and chitinase accumulated in common bean after infiltration with the pseudomonas syringae pv tabaci hrp- mutant pt11528::hrp1, even though a hypersensitive reaction did not occur. the temporal pattern of this transcript accumulation was similar to that seen after infiltration with wild-type p. s. tabaci pt11528, which resulted in a hypersensitive reaction. escherichia coli dh5[alpha], p. fluorescens pf101, heat-k ... | 1993 | 12271015 |
| suppression of bean defense responses by pseudomonas syringae. | we have developed a model system to examine suppression of defense responses in bean by the compatible bacterium pseudomonas syringae pv phaseolicola. previously, we have shown that there is a general mechanism for the induction of the bean defense genes phenylalanine ammonia-lyase (pal), chalcone synthase (chs), chalcone isomerase (chi), and chitinase (cht) by incompatible, compatible, and nonpathogenic bacteria. here, we show that bean plants infiltrated with isolates of p. s. phaseolicola fai ... | 1993 | 12271016 |
| volatile products of the lipoxygenase pathway evolved from phaseolus vulgaris (l.) leaves inoculated with pseudomonas syringae pv phaseolicola. | activation of the "lipoxygenase pathway" in plants gives rise to a series of products derived from fatty acids. analysis by gas chromatography-mass spectroscopy of volatile products produced by phaseolus vulgaris (l.) cv red mexican leaves during a hypersensitive resistance response (hr) to the plant pathogenic bacterium pseudomonas syringae pv phaseolicola showed evolution of several lipid-derived volatiles, including cis-3-hexenol and trans-2-hexenal, which arise from the 13-hydroperoxide of l ... | 1993 | 12231661 |
| water relation alterations observed during hypersensitive reaction induced by bacteria. | upon exposure to pathogenic bacteria, resistant and nonhost plants undergo a hypersensitive reaction (hr) that is expressed as rapid plant cell death. if sufficient concentrations of these bacteria are inoculated to such plant tissue, then that portion of the tissue rapidly collapses and becomes necrotic. as the tissue collapses the water relations of inoculated tissues become markedly disturbed. we measured a decline in the relative water content (rwc) in the leaf-like cotyledons of cotton (gos ... | 1993 | 12232016 |
| use of arabidopsis thaliana and pseudomonas syringae in the study of plant disease resistance and tolerance. | the interaction between arabidopsis thaliana and the bacterium pseudomonas syringae is being developed as a model experimental system for plant pathology research. race-specific ("gene-for-gene") resistance has been demonstrated for this interaction, and pathogen genes that determine avirulence have been isolated and characterized. because certain lines of both arabidopsis and soybean are resistant to bacteria carrying the avirulence genes avrrpt2 and avrb, extremely similar pathogen recognition ... | 1993 | 19279805 |
| molecular cloning, chromosomal mapping, and sequence analysis of copper resistance genes from xanthomonas campestris pv. juglandis: homology with small blue copper proteins and multicopper oxidase. | copper-resistant strains of xanthomonas campestris pv. juglandis occur in walnut orchards throughout northern california. the copper resistance genes from a copper-resistant strain c5 of x. campestris pv. juglandis were cloned and located on a 4.9-kb clai fragment, which hybridized only to dna of copper-resistant strains of x. campestris pv. juglandis, and was part of an approximately 20-kb region which was conserved among such strains of x. campestris pv. juglandis. hybridization analysis indic ... | 1994 | 8282694 |
| two native plasmids of pseudomonas syringae pathovar tomato strain pt23 share a large amount of repeated dna, including replication sequences. | strain pt23 of pseudomonas syringae pv. tomato contains four native plasmids, designated a, b, c, and d. by dna hybridization of genomic and plasmid dna digests from the wild type and a plasmid-cured strain, we determined that c. 61 kb (c. 74%) of ppt23b is repeated in ppt23 a and only c. 17 kb (c. 21%) is in single copy in strain pt23. ppt23b also contains dna repeated in the chromosome that occurs in three dna fragments of 0.6, 4.6, and 9.6 kb that might be transposable elements. additionally, ... | 1994 | 7934901 |
| erwinia chrysanthemi hrp genes and their involvement in soft rot pathogenesis and elicitation of the hypersensitive response. | unlike the bacterial pathogens that typically cause the hypersensitive response (hr) in plants, erwinia chrysanthemi has a wide host range, rapidly kills and macerates host tissues, and secretes several isozymes of the macerating enzyme pectate lyase (pel). pelabce- and out- (secretion-deficient) mutants were observed to produce a rapid necrosis in tobacco leaves that was indistinguishable from the hr elicited by the narrow-host-range pathogens e. amylovora ea321 and pseudomonas syringae pv. syr ... | 1994 | 7949326 |
| avirulence gene avrpphc from pseudomonas syringae pv. phaseolicola 3121: a plasmid-borne homologue of avrc closely linked to an avrd allele. | cosmid clone ppsp01 from race 1 pseudomonas syringae pv. phaseolicola isolate 3121 conferred a unique pattern of soybean cultivar reactions when expressed in p. s. pv. glycinea r4. the avirulence phenotype was shown to result from the presence in clone ppsp01 of an avrd allele as well as an additional avirulence gene located approximately 5-kb upstream. the new gene, called avrpphc, shows high identity to and is phenotypically identical to avrc, previously cloned from p. s. pv. glycinea race 0. ... | 1994 | 7949327 |
| ethylene production by strains of the plant-pathogenic bacterium pseudomonas syringae depends upon the presence of indigenous plasmids carrying homologous genes for the ethylene-forming enzyme. | the molecular characteristics of the ethylene-forming enzymes of strains of pseudomonas syringae were tested. the ethylene-producing activities of the nine strains as measured in vivo and in vitro were similar, except for that of p. syringae pv. mori m5. a polyclonal antibody and a dna probe for the ethylene-forming enzyme from p. syringae pv. phaseolicola pk2 were prepared to investigate homologies among the proteins and genes for the ethylene-forming enzymes. with the exception of p. syringae ... | 1994 | 7952184 |
| novel bioactive lipodepsipeptides from pseudomonas syringae: the pseudomycins. | the covalent structure and most of the stereochemistry of the pseudomycins, bioactive metabolites of a transposon-generated mutant of a pseudomonas syringae wild-type strain proposed for the biological control of dutch elm disease, have been determined. while two pseudomycins are identical to the known syringopeptins 25-a and 25-b, pseudomycins a, b, c, c' are new lipodepsinonapeptides. for all of these the peptide moiety corresponds to l-ser-d-dab-l-asp-l-lys-l-dab-l-athr-z-dhb-l-asp(3-oh) -l-t ... | 1994 | 7957970 |
| evaluation of determinative tests for pathovars of pseudomonas syringae van hall 1902. | the utility of 36 presumptive determinative tests for 32 pathovars of pseudomonas syringae was investigated. a total of 395 strains was examined. most strains of 12 of these pathovars (ps. syringae pv. cannabina, ps. syr. delphinii, ps. syr. glycinea, ps. syr. helianthi, ps. syr. lachrymans, ps. syr. mori, ps. syr. morsprunorum, ps. syr. phaseolicola, ps. syr. 'porri', ps. syr. papulans, ps. syr. savastanoi and ps. syr. tabaci) formed clusters when test data were compared by centroid analysis. p ... | 1994 | 7961191 |
| periplasmic glucans of pseudomonas syringae pv. syringae. | we report the initial characterization of glucans present in the periplasmic space of pseudomonas syringae pv. syringae (strain r32). these compounds were found to be neutral, unsubstituted, and composed solely of glucose. their size ranges from 6 to 13 glucose units/mol. linkage studies and nuclear magnetic resonance analyses demonstrated that the glucans are linked by beta-1,2 and beta-1,6 glycosidic bonds. in contrast to the periplasmic glucans found in other plant pathogenic bacteria, the gl ... | 1994 | 7961404 |
| genetic evidence that the gaca gene encodes the cognate response regulator for the lema sensor in pseudomonas syringae. | mutational analysis of the bean-pathogenic pseudomonas syringae pv. syringae strain b728a has led to the genetic identification of the gaca gene as encoding the response regulator for the unlinked lema sensor kinase. the analysis of a collection of spontaneous mutants of p. syringae pv. syringae suggested that the gaca gene was involved in lesion formation and the production of protease and syringomycin. the gaca gene originally was identified as a regulator of extracellular antibiotic productio ... | 1994 | 8002569 |
| the biosynthetic gene cluster for coronamic acid, an ethylcyclopropyl amino acid, contains genes homologous to amino acid-activating enzymes and thioesterases. | coronamic acid (cma), an ethylcyclopropyl amino acid derived from isoleucine, functions as an intermediate in the biosynthesis of coronatine, a chlorosis-inducing phytotoxin produced by pseudomonas syringae pv. glycinea pg4180. the dna required for cma biosynthesis (6.9 kb) was sequenced, revealing three distinct open reading frames (orfs) which share a common orientation for transcription. the deduced amino acid sequence of a 2.7-kb orf designated cmaa contained six core sequences and two conse ... | 1994 | 8002582 |
| plasmid-directed assembly of the lipid-containing membrane of bacteriophage phi 6. | the nucleocapsid of bacteriophage phi 6 is enveloped within a lipid-containing membrane. the membrane is composed of proteins p3, p6, p9, p10, and p13 and phospholipids. the relationship between membrane protein p9 and morphogenetic protein p12 was studied in the absence of phage infection. cdna copies of genes 9 and 12 were expressed on plasmids in pseudomonas syringae pv. phaseolicola. immunoblotting demonstrated the presence of protein p9 in strains carrying both gene 9 and gene 12 but not in ... | 1994 | 8021194 |
| phosphorylation of lipopolysaccharides in the antarctic psychrotroph pseudomonas syringae: a possible role in temperature adaptation. | phosphorylation of lipopolysaccharide (lps) from a psychrotrophic bacterium, pseudomonas syringae, from antarctica was studied by using sucrose gradient-separated membrane fractions. the bacterium was found to possess an lps kinase which could phosphorylate more lps postsynthetically at higher temperatures. the phosphorylation was low at a lower temperature and was also found to occur in vivo. after phosphorylation of lps in vitro, it was found that the major part of the radioactivity (> 85%) wa ... | 1994 | 8021210 |
| analysis of the streptomyces coelicolor sige gene reveals the existence of a subfamily of eubacterial rna polymerase sigma factors involved in the regulation of extracytoplasmic functions. | sigma e, an rna polymerase sigma factor of apparent m(r) 28,000, was previously identified by its ability to direct transcription from the p2 promoter of the agarose gene (daga) of streptomyces coelicolor. a degenerate oligonucleotide probe, designed from the n-terminal sequence of purified sigma e, was used to isolate the sigma e gene (sige). the predicted sequence of sigma e shows greatest similarity to sequences of seven other proteins: myxococcus xanthus carq, pseudomonas aeruginosa algu, ps ... | 1994 | 8052622 |
| characterization of ppt23b, the plasmid involved in syringolide production by pseudomonas syringae pv. tomato pt23. | avirulence gene d (avrd) in strain pt23 of pseudomonas syringae pv. tomato (pst) specifies the production of syringolides, which are elicitors of plant defense reactions. an 83-kb indigenous plasmid (ppt23b) that carries avrd has been mapped and characterized and a putative par region was identified. ppt23b contains a large amount of dna that is repeated in other native plasmids in pt23. a putative mobile insertion element that occurs on plasmid ppt23a as well as on the chromosome was also ident ... | 1994 | 8058820 |
| a disease resistance gene in arabidopsis with specificity for two different pathogen avirulence genes. | the rps3 and rpm1 disease resistance loci of arabidopsis confer resistance to pseudomonas syringae strains that carry the avirulence genes avrb and avrrpm1, respectively. we have previously shown that rps3 and rpm1 are closely linked genetically. here, we show that rps3 and rpm1 are in fact the same gene. we screened a mutagenized arabidopsis population with a p. syringae strain carrying avrb and found 12 susceptible mutants. all 12 mutants were also susceptible to an isogenic strain carrying av ... | 1994 | 8069104 |
| characterization of the hrpj and hrpu operons of pseudomonas syringae pv. syringae pss61: similarity with components of enteric bacteria involved in flagellar biogenesis and demonstration of their role in harpinpss secretion. | the hrp/hrma gene cluster of pseudomonas syringae pv. syringae pss61 has been shown to form a minimum genetic unit sufficient to enable nonpathogenic bacteria, such as escherichia coli, to elicit the hypersensitive response associated with disease resistance. the biochemical functions of most of these genes have not been established. the nucleotide sequence of a 4.3-kb ssti-bglii fragment carrying hrp apparent translational units v, vi, and vii revealed one partial open reading frame (orf) and f ... | 1994 | 8075421 |
| effect on lipopolysaccharide structure of aeration during growth of a plum isolate of pseudomonas syringae pv. morsprunorum. | the composition of lipopolysaccharide (lps) extracted with aqueous phenol from a virulent english plum isolate of pseudomonas syringae pv. morsprunorum varied according to the partial pressure of oxygen (po2) in the culture medium at the time of harvest. when po2 was low, the organism grew slowly and produced smooth lps bearing rhamnan sidechains. as po2 was raised, the rate of growth increased and smooth lps was replaced by a rough species deficient in rhamnose, which co-extracted with a d-gluc ... | 1994 | 8075800 |
| purification and characterization of copr, a transcriptional activator protein that binds to a conserved domain (cop box) in copper-inducible promoters of pseudomonas syringae. | the copper resistance (cop) operon promoter (pcop) of pseudomonas syringae is copper-inducible, and requires the regulatory genes coprs. sequence analysis revealed that copr has significant homology with other known activator proteins from bacterial two-component regulatory systems. in the present study we characterized pcop and its interaction with copr. we found that crude protein extracts from copper-resistant and -sensitive strains of p. syringae contain a pcop-specific dna-binding protein. ... | 1994 | 8078459 |