| [serological study of erwinia aroideae (townsend) holland and e. carotovora (jones) holland isolated from hyacinths and callas]. | | 1977 | 71650 |
| properties of the purified penicillin v-acylase of erwinia aroideae. | | 1975 | 234389 |
| [f'colvcolbtrpcys plasmid in erwinia aroideae]. | erwinia aroideae carries a cryptic plasmid with 30 s sedimentation coefficient. plasmid f'colvcolbtrpcys does not dissociate in e. aroideae and is replicated under stringent control since the number of plasmid copies per chromosome does not exceed one. the behaviour of f'colvcolbtrpcys plasmid in e. aroideae is characterized by (1) instability observed at both spontaneous and after eb treatment, (2) depression of plasmid genes that determine colicin synthesis. | 1978 | 346444 |
| a simple colorimetric method for determination of serum triglycerides with lipoprotein lipase and glycerol dehydrogenase. | a simplified enzymic procedure to determine accurately serum triglycerides is described. serum triglycerides are hydrolyzed completely to free fatty acids and glycerol by lipoprotein lipase from pseudomonas fluorescens. the released glycerol is oxidized with glycerol dehydrogenase from erwinia aroideae in the presence of nad+, were the reduction of the enzyme-linked nad+ is coupled to the reduction of nitro blue tetrazolium as a chromogenic indicator with phenazine methosulfate serving as an int ... | 1977 | 589792 |
| purification and some properties of glycerol dehydrogenase from erwinia aroideae. | | 1978 | 647848 |
| expression of peha-bla gene fusions in erwinia carotovora subsp. carotovora and isolation of regulatory mutants affecting polygalacturonase production. | in vitro gene fusions were constructed between the polygalacturonase-encoding peha gene of the erwinia carotovora subsp. carotovora (ecc) strain scc3193 and the bla gene of pbr322. the gene fusions obtained (75-2, 75-5 and 75-6) encoded hybrid proteins with the entire signal peptide and 70, 260 or 327 amino acids (aa) of the mature 376 aa peha protein, respectively, fused to the mature part of the periplasmic beta-lactamase. all three hybrid proteins remained cell-bound in ecc. high-level expres ... | 1992 | 1495488 |
| high-affinity iron uptake systems present in erwinia carotovora subsp. carotovora include the hydroxamate siderophore aerobactin. | the phytopathogenic bacterium erwinia carotovora subsp. carotovora w3c105 produced the hydroxamate siderophore aerobactin under iron-limiting conditions. a survey of 22 diverse strains of e. carotovora revealed that strain w3c105 alone produced aerobactin. the ferric-aerobactin receptor of strain w3c105 was an 80-kda protein, identified by immunoblots of sarkosyl-soluble proteins obtained from e. carotovora cells grown in iron-depleted medium and probed with antiserum raised against the 74-kda f ... | 1992 | 1569027 |
| expression of the erwinia carotovora polygalacturonase-encoding gene in bacillus subtilis: role of signal peptide fusions on production of a heterologous protein. | the peha gene encoding an endopolygalacturonase (pectinase) of erwinia carotovora subsp. carotovora has been cloned previously [saarilahti et al., mol. microbiol. 4 (1990) 1037-1044]. we expressed peha in bacillus subtilis using a secretion vector based on the promoter and signal sequence of the alpha-amylase (amy)-encoding gene, amye, from bacillus amyloliquefaciens. to test whether the location of the junction between the secretion vector and peha affects the protein yield, we made four differ ... | 1992 | 1628841 |
| genetic evidence for an activator required for induction of pectin lyase in erwinia carotovora subsp. carotovora by dna-damaging agents. | in erwinia carotovora subsp. carotovora 71, the induction of pectin lyase (pnl), the bacteriocin carotovoricin (ctv), and cellular lysis (lss) requires a reca function. we obtained mutants wherein a pleiotropic defect, i.e., the lack of induction with mitomycin c, is not restored by the reca+ dna. from a genomic library of strain 71, a cosmid (pakc280) that restored induction of pnl, ctv, and lss by mitomycin c was isolated. the activator function, designated rdg for regulator of damage-inducibl ... | 1992 | 1644776 |
| nucleotide sequence and molecular characterization of pnla, the structural gene for damage-inducible pectin lyase of erwinia carotovora subsp. carotovora 71. | in a previous study, pnla (the dna damage-inducible structural gene for pectin lyase) of erwinia carotovora subsp. carotovora 71 was localized to a 1.4-kb dna segment within a 3.4-kb ecori fragment (j. l. mcevoy, h. murata, and a. k. chatterjee, j. bacteriol. 172:3284-3289, 1990). we present here dna sequence data for a 2.2-kb region revealing an open reading frame of 870 bases, corresponding to a protein (pnl) of an approximate molecular mass of 32,100 da and an isoelectric point of 9.92. altho ... | 1991 | 1705542 |
| differential activation of potato 3-hydroxy-3-methylglutaryl coenzyme a reductase genes by wounding and pathogen challenge. | potato genes encoding 3-hydroxy-3-methylglutaryl coenzyme a reductase (hmgr) were expressed in response to pathogen, elicitor, and wounding. hmgr catalyzes the rate-limiting step in isoprenoid biosynthesis leading to accumulation of phytoalexins and steroid glycoalkaloids. wounding caused increases in hmgr mrna levels. a rapid and transient peak occurred 30 minutes after wounding, followed by a slower peak at 14 hours; both were correlated with increased enzyme activity. induction of hmgr mrna b ... | 1991 | 1840919 |
| erwinia carotovora subsp. carotovora extracellular protease: characterization and nucleotide sequence of the gene. | the prt1 gene encoding extracellular protease from erwinia carotovora subsp. carotovora ec14 in cosmid pca7 was subcloned to create plasmid psk1. the partial nucleotide sequence of the insert in psk1 (1,878 bp) revealed a 1,041-bp open reading frame (orf1) that correlated with protease activity in deletion mutants. orf1 encodes a polypeptide of 347 amino acids with a calculated molecular mass of 38,826 da. escherichia coli transformed with psk1 or psk23, a subclone of psk1, produces a protease ( ... | 1991 | 1917878 |
| molecular cloning of omprs, a regulatory locus controlling production of outer membrane proteins in erwinia carotovora subsp. carotovora. | a locus, omprs, controlling synthesis of outer membrane proteins was cloned from erwinia carotovora subsp. carotovora (ecc) by complementation of an escherichia coli ompr-envz mutant. the ecc omprs locus was both structurally and functionally similar to the ompr-envz operon controlling porin gene expression in e. coli as shown by dna hybridization and complementation of e. coli ompr and envz mutants. furthermore, introduction of omprs into e. coli delta (ompr-envz) strains restored the osmoregul ... | 1991 | 2038301 |
| characterization of transposon insertion out- mutants of erwinia carotovora subsp. carotovora defective in enzyme export and of a dna segment that complements out mutations in e. carotovora subsp. carotovora, e. carotovora subsp. atroseptica, and erwinia chrysanthemi. | soft-rotting erwinia spp. export degradative enzymes to the cell exterior (out+), a process contributing to their ability to macerate plant tissues. transposon (tn5, tn10, tn10-lacz) insertion out- mutants were obtained in erwinia carotovora subsp. carotovora 71 by using plasmid and bacteriophage lambda delivery systems. in these mutants, pectate lyases, polygalacturonase, and cellulase, which are normally excreted into the growth medium, accumulated in the periplasm. however, localization of th ... | 1990 | 2160934 |
| molecular cloning and characterization of an erwinia carotovora subsp. carotovora pectin lyase gene that responds to dna-damaging agents. | reca-mediated production of pectin lyase (pnl) and the bacteriocin carotovoricin occurs in erwinia carotovora subsp. carotovora 71 when this organism is subjected to agents that damage or inhibit the synthesis of dna. the structural gene pnla was isolated from a strain 71 cosmid gene library following mobilization of the cosmids into a moderate pnl producer, strain 193. the cosmid complemented pnl::tn5 but not ctv::tn5 mutations. a constitutive level of pnl activity was detected in reca+ and rec ... | 1990 | 2188956 |
| sequence of the peh gene of erwinia carotovora: homology between erwinia and plant enzymes. | polygalacturonase (peh) and other pectolytic enzymes play a crucial role in the maceration of vegetables by soft rot erwinia spp. we have sequenced the peh gene of erwinia carotovora subsp. carotovora, and identified its product as a precursor of molecular weight 42,639, and a mature protein of molecular weight 42,200. a putative kdgr-binding site was identified in the region 5' to the peh gene. the peh protein showed significant homology with peh from tomato. in addition, we have found homologi ... | 1990 | 2215211 |
| cels: a novel endoglucanase identified from erwinia carotovora subsp. carotovora. | a plasmid clone expressing a beta(1,4)-glucan glucanohydrolase (ec 3.2.1.4; endoglucanase) in escherichia coli was isolated from a genomic library of erwinia carotovora subsp. carotovora. the dna segment carrying the corresponding structural gene, named cels, contained an open reading frame encoding a 264-amino acid (aa) polypeptide. the n-terminal aa sequence of cels showed that the protein was synthesized with a 32-aa cleavable signal peptide. the mature 232-aa cels had a calculated mr of 26,2 ... | 1990 | 2379837 |
| [characteristics of the lipopolysaccharides in erwinia carotovora subsp. carotovora 8883 isolated by various methods]. | | 1989 | 2725355 |
| characterization of type 1 and mannose-resistant fimbriae of erwinia spp. | type 1 fimbriae from erwinia carotovora subsp. carotovora and mannose-resistant fimbriae from erwinia rhapontici were purified and characterized. the type 1 fimbrillin had an apparent molecular weight of 16,500; that of the mannose-resistant fimbrillin was 18,000. the amino-terminal amino acid sequences of the two fimbrillins were related, but tryptic peptide maps showed significant differences between the proteins. no serological cross-reaction was found between the two fimbrial filaments, nor ... | 1987 | 2883172 |
| chromosomal mapping in erwinia carotovora subsp. carotovora with the incp plasmid r68::mu. | conjugational gene transfer was established in erwinia carotovora subsp. carotovora scri193 by using plasmid r68::mu c+ to mobilize the chromosome into multiply mutant recipients. it was observed that although the plasmid alone mobilized markers randomly at a frequency of ca. 10(-5) chromosomal recombinants per donor, the presence of a mu prophage on the chromosome of the donor increased the frequency of mobilization of markers adjacent to the prophage by up to 10-fold. using this system it was ... | 1985 | 2933392 |
| effects of a mutation that eliminates udp glucose-pyrophosphorylase on the pathogenicity of erwinia carotovora subsp. carotovora. | a nonpathogenic mutant of erwinia carotovora obtained by mu d1 mutagenesis was defective in the ability to utilize several carbon sources. the basis of the mutation was analyzed biochemically and shown to be a defect in the ability to form udp glucose-pyrophosphorylase. the nonpathogenic phenotype of the mutant was caused by its sensitivity to galactose. | 1985 | 2995320 |
| requirement for two or more erwinia carotovora subsp. carotovora pectolytic gene products for maceration of potato tuber tissue by escherichia coli. | several genes encoding enzymes capable of degrading plant cell wall components have been cloned from erwinia carotovora subsp. carotovora ec14. plasmids containing cloned ec14 dna mediate the production of endo-pectate lyases, exo-pectate lyase, endo-polygalacturonase, and cellulase(s). escherichia coli strains containing one of these plasmids or combinations of two plasmids were tested for their ability to macerate potato tuber slices. only one e. coli strain, containing two plasmids that encod ... | 1986 | 3013836 |
| endopectate lyase from erwinia aroideae. | | 1988 | 3226298 |
| [the monosaccharide composition of erwinia carotovora subsp. carotovora cells]. | | 1987 | 3508943 |
| 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 ... | 1987 | 3625474 |
| comparison of pectic enzymes produced by erwinia chrysanthemi, erwinia carotovora subsp. carotovora, and erwinia carotovora subsp. atroseptica. | erwinia spp. that cause soft-rot diseases in plants produce a variety of extracellular pectic enzymes. to assess the correlation between patterns of pectic enzyme production and taxonomic classification, we compared the enzymes from representative strains. supernatants obtained from polygalacturonate-grown cultures of nine strains of erwinia chrysanthemi, three strains of e. carotovora subsp. carotovora, and three strains of e. carotovora subsp. atroseptica were concentrated and subjected to ult ... | 1986 | 3752996 |
| cloning and expression in escherichia coli of pectinase genes of erwinia carotovora subsp. carotovora. | genes coding for an endo-pectate lyase, an exo-pectate lyase, and an endopolygalacturonase of erwinia carotovora subsp. carotovora ecc71 were cloned in escherichia coli hb101, using the cosmid phc79. the products of the cloned pectinase genes paralleled their counterparts in strain ecc71 in isoelectric mobility, mode of substrate degradation, and ability to macerate potato tuber tissue. | 1985 | 3888112 |
| efficient transformation of erwinia carotovora subsp. carotovora and e. carotovora subsp. atroseptica. | we used a modified version of the method of hanahan (d. hanahan, j. mol. biol. 166:557-580, 1983) to transform erwinia carotovora subsp. carotovora and e. carotovora subsp. atroseptica with the plasmids pbr322, pbr325, and pat153. the transformation frequency ranged from 1 x 10(2) to 4 x 10(4) colonies per micrograms of plasmid dna. the nature of these transformants was confirmed by plasmid analysis. cole1-based plasmids make potentially useful cloning vectors for the study of genes involved in ... | 1985 | 3968041 |
| reca is required in the induction of pectin lyase and carotovoricin in erwinia carotovora subsp. carotovora. | pectin lyase (pnl) and the bacteriocin carotovoricin (ctv) were induced in erwinia carotovora subsp. carotovora 71 by the dna-damaging agents mitomycin c, nalidixic acid, and uv light. to determine whether the reca product was involved in the expression of these damage-inducible phenotypes, we cloned the e. carotovora subsp. carotovora reca+ gene, inactivated it by tn5 insertion, and constructed an e. carotovora subsp. carotovora reca::tn5 strain by gene replacement via homologous recombination. ... | 1985 | 4044526 |
| [study of penicillin-acylase produced by erwinia aroideae]. | | 1971 | 4335226 |
| effect of carbon and nitrogen sources on the production of l-asparaginase by erwinia aroideae. | | 1972 | 4516164 |
| fermentation kinetics and continuous process of l-asparaginase production. | for the purpose of obtaining l-asparaginase in quantities from erwinia aroideae, cell growth and enzyme formation were investigated in both batch and continuous fermentation. using yeast extract as a growth-limiting substrate, the relationship between specific growth rate and substrate concentration was found to fit the monod equation. the optimum temperature for enzyme production was 24 c, although cell growth was higher at 28 c. the enzyme yield reached its maximum of 4 iu/ml during the negati ... | 1973 | 4568894 |
| purification and properties of l-asparaginase of erwinia aroideae. | | 1972 | 4649741 |
| effect of oxygen-transfer rate on production of l-asparaginase by erwinia aroideae. | | 1973 | 4754750 |
| a comparison of l-asparaginase from erwinia aroideae and from escherichia coli: biochemical and biological properties. | | 1971 | 4993733 |
| l-asparaginase synthesis by erwinia aroideae. | maximum l-asparaginase activity was obtained when 1.0% lactose and 1.5% yeast extract were supplied as carbon and nitrogen sources, respectively. glucose inhibited the enzyme formation. the diauxie phenomenon was observed with erwinia aroideae nrrl b-138 grown in a medium containing glucose and lactose. | 1972 | 5021978 |
| factors influencing l-asparaginase production by erwinia aroideae. | increased yields of l-asparaginase from erwinia aroideae nrrl b-138 were obtained by medium enrichment techniques coupled with aeration optimization. | 1972 | 5021980 |
| l-asparaginase production by various bacteria. | of 123 species of bacteria surveyed for l-asparaginase synthesis, erwinia aroideae nrrl b-138 provided the highest yields. | 1969 | 5797949 |
| l-asparaginase production by erwinia aroideae. | maximum yields of 1,250 iu (international unit)/g (dry weight of cells) of l-asparaginase were obtained in 8 hr from erwinia aroideae nrrl b-138. partial purification and concentration of the extracted l-asparaginase yielded a preparation with an activity of 275 iu/ml. only one l-asparaginase was present as determined by electrophoresis, and the enzyme exhibited a ph optimum of 7.5 and a k(m) of 3 x 10(-3) m. | 1969 | 5803630 |
| mutagenesis of erwinia carotovora subsp. carotovora with bacteriophage mu d1 (apr lac cts62): construction of his-lac gene fusions. | the bacteriophage mu d1(apr lac cts62 ) obtained from an escherichia coli double lysogen carrying the defective mu d1 phage and a mu-p1 hybrid phage was utilized as a vector for phage mutagenesis in erwinia carotovora subsp. carotovora. among ampicillin-resistant transductants. 1.4% were auxotrophs. the synthesis of beta-galactosidase was derepressed upon starvation for histidine in two different his-lac fusion strains. | 1984 | 6233263 |
| transposon tn5 mutagenesis in erwinia carotovora subsp. carotovora and e. carotovora subsp. atroseptica. | in matings between escherichia coli 2492(pjb4ji) and erwinia carotovora subsp. carotovora ecc71 and e. carotovora subsp. atroseptica eca12, kmr gms transconjugants were obtained at high frequencies, indicating instability of the mu-containing plasmid pjb4ji and transposition of tn5 into the recipient genome. this was verified by southern blot hybridization with prz102 dna containing tn5 as the 32p-labeled probe. examination of kmr gms transconjugants of ecc71 and eca12 disclosed that a proportio ... | 1984 | 6321435 |
| changes in properties of phytopathogenic bacteria effected by plasmid prd1. | transfer of plasmid prd1 from escherichia coli k 12j62 -1 to phytopathogenic bacteria, agrobacterium tumefaciens, xanthomonas beticola and erwinia carotovora subsp. carotovora caused changes in conjugant properties not determined by the plasmid and the emergence of the properties not present in the parent strains. clones have been obtained with intermediate properties between donor and recipient, including those with altered or lost virulence. in transconjugants of a. tumefaciens virulence incre ... | 1984 | 6375619 |
| enzymatic synthesis of phenoxymethylpenicillin using erwinia aroideae enzyme. | enzymatic synthesis of phenoxymethylpenicillin from 6-aminopenicillanic acid and phenoxyacetic acid methyl ester was attempted by using partially purified alpha-acylamino-beta-lactam acylhydrolase i (alahase i) enzyme from erwinia aroideae nrrl b-138. the reaction rates were carefully followed by determination of 6-aminopenicillanic acid (6-apa), phenoxymethylpenicillin (pnv), phenoxyacetic acid (poa), phenoxyacetic acid methyl ester (pom), and phenoxyacetylglycine (pog) using high performance l ... | 1984 | 6438038 |
| plasmid pea566 from erwinia aroideae. | a new plasmid designated pea566 was isolated from erwinia aroideae. the molecular weight of the plasmid, as determined by neutral and alkaline sucrose gradient centrifugation, electron microscopy, and agarose gel electrophoresis, was 6.6 x 10(6). the plasmid replicated under relaxed control, had three cleavage sites for kpni restriction endonuclease, and no sites for ecori, bamhi, sali, psti, and hindiii. | 1980 | 6927815 |
| [properties of the bacteriocin of erwinia aroideae]. | erwinicin, produced by erwinia aroideae cells, consists of rod-shaped particles. the molecular weight of such particles, determined by the method of sedimentation in saccharose gradient, is 15 megadaltons. the size of the particles is 14 x 160 nm. the preparations of erwinicin are thermolabile, insensitive to the action of rnaase, pronase, dnaase and possess antigenic properties. the synthesis of erwinicin is an inducible process. | 1980 | 7190345 |
| cloning and sequencing of the gyra gene from the plant pathogen erwinia carotovora. | the gyra gene of erwinia carotovora subsp. carotovora has been cloned and sequenced. the deduced protein possessed 86% identity with the escherichia coli gyra protein. e. carotovora gyra was also shown to complement an e. coli gyra43ts mutation. | 1995 | 7642123 |
| inactivation of rsma leads to overproduction of extracellular pectinases, cellulases, and proteases in erwinia carotovora subsp. carotovora in the absence of the starvation/cell density-sensing signal, n-(3-oxohexanoyl)-l-homoserine lactone. | the soft-rotting bacterium, erwinia carotovora subsp. carotovora 71, produces extracellular enzymes such as pectate lyase isozymes (pels), cellulase (cel), polygalacturonase (peh), and protease (prt). while the extracellular levels of these enzymes are extremely low when the bacterium is grown in salts-yeast extract-glycerol (syg) medium, the enzymatic activities are highly induced in syg medium supplemented with celery extract. by transposon (mini-tn5) mutagenesis, we isolated a rsma- mutant, a ... | 1995 | 7646031 |
| identification of a global repressor gene, rsma, of erwinia carotovora subsp. carotovora that controls extracellular enzymes, n-(3-oxohexanoyl)-l-homoserine lactone, and pathogenicity in soft-rotting erwinia spp. | the production of extracellular enzymes such as pectate lyase (pel), polygalacturonase (peh), cellulase (cel), and protease (prt) is activated by the cell density (quorum)-sensing signal, n-(3-oxohexanoyl)-l-homoserine lactone (hsl); plant signals; and aep genes during postexponential growth of erwinia carotovora subsp. carotovora 71. studies with mutants of e. carotovora subsp. carotovora 71 derepressed in exoenzyme production led to the identification of a negative regulator gene, rsma (rsm, r ... | 1995 | 7665490 |
| nucleotide sequence, organization and expression of rdga and rdgb genes that regulate pectin lyase production in the plant pathogenic bacterium erwinia carotovora subsp. carotovora in response to dna-damaging agents. | in most soft-rotting erwinia spp., including e. carotovora subsp. carotovora strain 71 (ecc71), production of the plant cell wall degrading enzyme pectin lyase (pnl) is activated by dna-damaging agents such as mitomycin c (mc). induction of pnl production in ecc71 requires a functional reca gene and the rdg locus. dna sequencing and rna analyses revealed that the rdg locus contains two regulatory genes, rdga and rdgb, in separate transcriptional units. there is high homology between rdga and rep ... | 1994 | 7715460 |
| structure and regulation of the erwinia carotovora subspecies carotovora scc3193 cellulase gene celv1 and the role of cellulase in phytopathogenicity. | the celv1 gene encoding a secreted cellulase (celv1) of erwinia carotovora subsp. carotovora scc3193 was cloned and its nucleotide sequence determined. the gene contains an open reading frame of 1511 bp and codes for an exported protein of 504 amino acids. the predicted amino acid sequence of celv1 was highly similar to that of celv of another e. c. subsp. carotovora strain scr1193 but completely different from the previously characterized cellulase, cels, of the strain scc3193. gene fusions to ... | 1995 | 7715600 |
| [expression of pectate lyase genes of erwinia carotovora subsp. carotovora 17a and erwinia carotovora subsp. atroseptica 36a in erwinia carotovor substp. atroseptica 36a cells]. | e.atroseptica 36a cells were transformed by the recombinant plasmids p27-1 and pea364 (derivatives of the vector plasmid puc19) containing pectate lyase genes of e.carotovora 17a and e.atroseptica 36a, respectively. the synthesis of pectate lyases determined by the cloned genes of bacteria of both subspecies, as well as the synthesis of the native enzymes, were induced by sodium poly pectate. increase of the dose of pectate lyase genes did not result in alteration of pectate lyase secretion by e ... | 1994 | 7739592 |
| characterization of a novel pectate lyase from erwinia carotovora subsp. carotovora. | the pectate lyase (pel, ec 4.2.2.2) isoenzyme profile of erwinia carotovora subsp. carotovora was characterized by isoelectric focusing, and the corresponding genes coding for four different exported pels were cloned. the nucleotide sequence of the pelb gene encoding one of these isoenzymes was determined and was shown to contain 1,040-bp open reading frame coding for a 37,482-da protein with a putative cleavable amino terminal signal peptide. overexpression and selective labeling experiments wi ... | 1995 | 7756691 |
| nucleotide sequence of a pectate lyase structural gene, pel1 of erwinia carotovora subsp. carotovora strain 71 and structural relationship of pel1 with other pel genes of erwinia species. | of the various exoproteins secreted by erwinia carotovora subsp. carotovora strain 71, pel1 is the major pectate lyase species with tissue macerating activity. nucleotide sequencing of a 2.2-kb pel1+ dna segment revealed a 1,122 base pair open reading frame which could encode pre-pel1 of 374 amino acid residues. a signal peptide of 22 amino acid residues is present within the nh2-terminal region of pre-pel1. transcription of pel1 was initiated at the guanine residue 111 base pairs upstream of th ... | 1995 | 7772808 |
| pcr and restriction fragment length polymorphism of a pel gene as a tool to identify erwinia carotovora in relation to potato diseases. | using a sequenced pectate lyase-encoding gene (pel gene), we developed a pcr test for erwinia carotovora. a set of primers allowed the amplification of a 434-bp fragment in e. carotovora strains. among the 89 e. carotovora strains tested, only the erwinia carotovora subsp. betavasculorum strains were not detected. a restriction fragment length polymorphism (rflp) study was undertaken on the amplified fragment with seven endonucleases. the sau3ai digestion pattern specifically identified the erwi ... | 1994 | 7912502 |
| regulation of the production of extracellular pectinase, cellulase, and protease in the soft rot bacterium erwinia carotovora subsp. carotovora: evidence that aeph of e. carotovora subsp. carotovora 71 activates gene expression in e. carotovora subsp. carotovora, e. carotovora subsp. atroseptica, and escherichia coli. | the production of pectolytic enzymes (pectate lyase [pel] and polygalacturonase [peh]), cellulase (cel), and protease (prt) is activated in the soft rot bacterium erwinia carotovora subsp. carotovora by aepa (activator of extracellular protein production) and celery extract (y. liu, h. murata, a. chatterjee, and a. k. chatterjee, mol. plant-microbe interact. 6:299-308, 1993). we recently isolated a new class of mutants of strain e. carotovora subsp. carotovora 71 which overproduces pel, peh, cel ... | 1994 | 7944360 |
| beta-lactamase topology probe analysis of the outo nmephe peptidase, and six other out protein components of the erwinia carotovora general secretion pathway apparatus. | the out gene cluster of erwinia spp. encodes the proteins of the general secretory pathway (gsp) apparatus that is required for pectinase and cellulase secretion. we have used fusions between erwinia carotovora subsp. carotovora (ecc) out genes and the topology probe blam to assess the ability of out protein regions to export blam across the cytoplasmic membrane in escherichia coli and ecc. for the outo gene product (an nmephe peptidase), seven transmembrane regions have been identified and one ... | 1994 | 8065262 |
| nucleotide sequence and expression of a novel pectate lyase gene (pel-3) and a closely linked endopolygalacturonase gene (peh-1) of erwinia carotovora subsp. carotovora 71. | our previous genetic analysis (j. w. willis, j. k. engwall, and a. k. chatterjee, phytopathology 77:1199-1205, 1987) had revealed a tight linkage between pel-3 (pel, pectate lyase gene) and peh-1 (peh, polygalacturonase gene) within the chromosome of erwinia carotovora subsp. carotovora 71. nucleotide sequencing, transcript assays, and expression of enzymatic activities in escherichia coli have now confirmed that a 3,500-bp segment contains the open reading frames (orfs) for pel-3 and peh-1. the ... | 1994 | 8074530 |
| characterization of a novel regulatory gene aepa that controls extracellular enzyme production in the phytopathogenic bacterium erwinia carotovora subsp. carotovora. | erwinia carotovora subsp. carotovora strain ecc71 produces an array of extracellular enzymes including pectate lyase (pel), polygalacturonase, cellulase, and protease. in strain ecc71, these enzymes are coregulated by aepa, which encodes an activator of extracellular protein production (h. murata, j. l. mcevoy, a. chatterjee, a. collmer, and a. k. chatterjee, mol. plant-microbe interact, 4:239-246, 1991). the nucleotide sequence of a 2.7-kb aepa+ dna segment revealed an open reading frame (orf) ... | 1993 | 8324248 |
| proton-linked l-rhamnose transport, and its comparison with l-fucose transport in enterobacteriaceae. | 1. an alkaline ph change occurred when l-rhamnose, l-mannose or l-lyxose was added to l-rhamnose-grown energy-depleted suspensions of strains of escherichia coli. this is diagnostic of sugar-h+ symport activity. 2. l-rhamnose, l-mannose and l-lyxose were inducers of the sugar-h+ symport and of l-[14c]rhamnose transport activity. l-rhamnose also induced the biochemically and genetically distinct l-fucose-h+ symport activity in strains competent for l-rhamnose metabolism. 3. steady-state kinetic m ... | 1993 | 8384447 |
| a note on the primary structure and expression of an erwinia carotovora polygalacturonase-encoding gene (peh1) in escherichia coli and saccharomyces cerevisiae. | a 1209-base pair (bp) dna fragment containing the endopolygalacturonase-encoding gene (peh1) from erwinia carotovora subsp. carotovora was amplified by the polymerase chain reaction (pcr) technique and expressed in escherichia coli. the nucleotide sequence of the pcr product was determined and found to be highly homologous to the primary structures of other polygalacturonase-encoding genes. the peh1 dna fragment encoding the mature polygalacturonase was inserted between two different yeast expre ... | 1993 | 8407675 |
| characterization of polygalacturonases. | lei et al. [gene 117 (1992) 119-124] recently published the nucleotide sequence of the peh gene of erwinia carotovora subsp. carotovora (ecc) and a characterization of its product endopolygalacturonase (peh). the gene appears highly similar to previously described peh sequences of ecc [hinton et al., mol. microbiol. 4 (1990) 1029-1036; saarilahti et al., mol. microbiol. 4 (1990) 1037-1044] which were not cited in the article. ecc carries a single peh gene whose product, peh, is here shown to sha ... | 1993 | 8440478 |
| purification, partial characterization, and subcellular localization of a 38 kilodalton, calcium-regulated protein of rhizobium fredii usda208. | calcium is essential for the growth of rhizobia and the formation of nitrogen-fixing root-nodules on legumes, but its precise role in these processes remains unknown. we have found that rhizobium fredii usda208 accumulates a major 38 kda protein when grown in media supplemented with 0.3-2 microm cacl2. we have purified this protein and raised polyclonal antibodies against it. the protein initially is synthesized as a 40 kda precursor which subsequently undergoes calcium-dependent processing to g ... | 1993 | 8481090 |
| a small diffusible signal molecule is responsible for the global control of virulence and exoenzyme production in the plant pathogen erwinia carotovora. | virulence of the plant pathogen erwinia carotovora subsp. carotovora is dependent on the production and secretion of a complex arsenal of plant cell wall-degrading enzymes. production of these exoenzymes is controlled by a global regulatory mechanism. a virulent mutants in one of the regulatory loci, expi, show a pleiotropic defect in the growth phase-dependent transcriptional activation of exoenzyme gene expression. the expi gene encodes a 26 kda polypeptide that is structurally and functionall ... | 1993 | 8508772 |
| disease resistance conferred by expression of a gene encoding h2o2-generating glucose oxidase in transgenic potato plants. | plant defense responses to pathogen infection involve the production of active oxygen species, including hydrogen peroxide (h2o2). we obtained transgenic potato plants expressing a fungal gene encoding glucose oxidase, which generates h2o2 when glucose is oxidized. h2o2 levels were elevated in both leaf and tuber tissues of these plants. transgenic potato tubers exhibited strong resistance to a bacterial soft rot disease caused by erwinia carotovora subsp carotovora, and disease resistance was s ... | 1995 | 8589621 |
| [the antibiotic properties of the phytotoxic metabolites of botrytis cinerea pers]. | antibiotic properties of substances of a phytotoxic complex from botrytis cinerea have been studied for a number of phytopathogenic bacteria, phytopathogenic and toxigenic fungi as well as saprophytic yeast strains. high fungistatic activity of preparations of phytotoxic metabolites (ptm) has been stated for dendrodochium toxicum, myrothecium verrucaria, m. roridum, aspergillus fumigatus, penicillium urticae, agents of heavy human and cattle mycotoxicoses. the studied representatives of phytopat ... | 1995 | 8714399 |
| the rsma- mutants of erwinia carotovora subsp. carotovora strain ecc71 overexpress hrpnecc and elicit a hypersensitive reaction-like response in tobacco leaves. | erwinia carotovora subsp. carotovora wild-type strain ecc71 does not elicit the hypersensitive reaction (hr) in tobacco leaves. by mini-tn5-km and chemical mutagenesis we have isolated rsma- mutants of ecc71 that produce high basal levels of pectate lyases, polygalacturonase, cellulase, and protease; they also are hypervirulent. the rsma- mutants, but not their parent strains, elicit an hr-like response in tobacco leaves. this reaction is characterized by the rapid appearance of water soaking fo ... | 1996 | 8810071 |
| global regulation in erwinia species by erwinia carotovora rsma, a homologue of escherichia coli csra: repression of secondary metabolites, pathogenicity and hypersensitive reaction. | our previous studies revealed that rsma of erwinia carotovora subsp. carotovora strain 71 suppressed the synthesis of the cell density (quorum) sensing signal n-(3-oxohexanoyl)-l-homoserine lactone, the production of extracellular enzymes and tissue macerating ability in soft-rotting erwinia species and that homologues of this negative regulator gene were present in other erwinia species. northern blot data presented here demonstrate that rsma and rsma-like genes are also expressed in soft-rotti ... | 1996 | 8932714 |
| identification of a pathogenicity locus, rpfa, in erwinia carotovora subsp. carotovora subsp. carotovora that encodes a two-component sensor-regulator protein. | a mutant of erwinia carotovora subsp. carotovora, ah2552, created by a mud1 insertion was found to be reduced in plant pathogenicity and deficient in extracellular protease and cellulase activity, although it produced normal levels of pectate lyase and polygalacturonase. a cosmid clone, pec462, was isolated from a wild-type e. carotovora subsp. carotovora dna library that concomitantly restored pathogenicity and protease and cellulase activities of ah2552 to wild-type levels when present in tran ... | 1997 | 9100385 |
| molecular characterization and expression of the erwinia carotovora hrpnecc gene, which encodes an elicitor of the hypersensitive reaction. | the nucleotide sequence of hrpnecc dna, cloned from erwinia carotovora subsp. carotovora strain ecc71, reveals a coding region of 1,068 bp which matches the size of hrpnecc transcripts. hrpnecc is predicted to encode a glycine-rich protein of approximately 36 kda. like the elicitors of the hypersensitive reaction (hr) produced by e. chrysanthemi (harpinech) and e. amylovora (harpinea), the deduced 36-kda protein does not possess a typical signal sequence, but it contains a putative membrane-span ... | 1997 | 9150595 |
| mobilization, cloning, and sequence determination of a plasmid-encoded polygalacturonase from a phytopathogenic burkholderia (pseudomonas) cepacia. | phytopathogenic strains of burkholderia cepacia (synonym pseudomonas cepacia) produce endopolygalacturonase, whereas strains of clinical and soil origin do not. growth of a phytopathogenic strain (atcc25416) at elevated temperatures resulted in nonpectolytic derivatives that were either cured of a resident plasmid or contained a plasmid of reduced mass. the resident 200-kb plasmid (ppec320) in strain atcc25416 was tagged with tn5-mob. the ppec320::tn5-mob (ppec321) plasmid was mobilized in b. ce ... | 1997 | 9304858 |
| characterization of erwinia carotovora subsp. carotovora ly34 endo-1,4-beta-glucanase genes and rapid identification of their gene products. | genomic dna of the phytopathogenic erwinia carotovora subsp. carotovora ly34 was partially digested with sau3ai, ligated into the bamhi site of pblue-script ii sk+, and introduced into e. coli. two clones that were able to hydrolyse carboxymethylcellulose were selected. 1.5 kb and 1.2 kb fragments containing the cela and celb genes, respectively, were subcloned and sequenced. the cela and celb genes had open reading frames of 1,161 bp and 792 bp encoding 487 and 264 amino acid residues with calc ... | 1997 | 9434760 |
| ecbi and ecbr: homologs of luxi and luxr affecting antibiotic and exoenzyme production by erwinia carotovora subsp. betavasculorum. | erwinia carotovora subsp. betavasculorum ecb168 causes vascular necrosis and root rot of sugar beet and produces an antibiotic(s) that is antagonistic against other erwinia spp. ecbi- mutants of ecb168, each containing a single transposon insertion in the ecbi gene (for erwinia carotovora subsp. betavasculorum inducer), do not produce detectable levels of extracellular protease or antibiotic(s), and express less pectate lyase activity and virulence than the wild-type strain. a plasmid containing ... | 1997 | 9476353 |
| cloning and sequencing of the cela gene encoding cmcase of erwinia carotovora subsp. carotovora ly34. | the phytopathogenic erwinia carotovora subsp. carotovora ly34 secretes multiple isozymes of the plant cell wall-disintegrating enzyme, endoglucanases. genomic dna from ecc ly34 was digested with sau3ai and ligated into the bamhi site of pbluescript ii sk+. one of the e. coli clones containing a sau3ai fragment of ecc genomic dna hydrolyzed carboxymethyl cellulose and was shown to contain the 2.2 kb bamhi restriction fragment, which was subcloned to generate plyca100 named as cela. the structural ... | 1998 | 9571628 |
| two-component regulators involved in the global control of virulence in erwinia carotovora subsp. carotovora. | production of extracellular, plant cell wall degrading enzymes, the main virulence determinants of the plant pathogen erwinia carotovora subsp. carotovora, is coordinately controlled by a complex regulatory network. insertion mutants in the exp (extracellular enzyme production) loci exhibit pleiotropic defects in virulence and the growth-phase-dependent transcriptional activation of genes encoding extracellular enzymes. two new exp mutations, designated expa and exps, were characterized. introdu ... | 1998 | 9675890 |
| characterization of pucd5000 involved in pink disease color formation by pantoea citrea. | pantoea citrea, the causal agent of pink disease of pineapple, harbors a cryptic plasmid of 5229 bp. designated pucd5000. on the basis of nucleotide and amino acid sequence analyses, pucd5000 contains both replication and mobilization loci (bom and mobcabd) that are similar to those in plasmids psw100 and psw200 in pantoea stewartii and pec3 in erwinia carotovora subsp. carotovora. the survival of p. citrea on pineapple does not depend on pucd5000. however, full pink coloration development, whic ... | 1998 | 9735319 |
| bacillus subtilis bs 107 as an antagonist of potato blackleg and soft rot bacteria. | antimicrobial substances were produced by bacillus subtilis bs 107 in a defined medium and isolated from culture filtrate by precipitation at ph 2.5. active fractions were extracted in ethyl acetate, acetone, and 80% ethanol and purified by thin-layer chromatography (tlc) on silica gel plates developed with an ethanol-water mixture (2:1, v/v). in each case, a band with a rf of 0.75 formed an inhibitory zone when the tlc plates were placed in contact with agar seeded with test cultures of the erw ... | 1998 | 9830107 |
| enhanced resistance to bacterial diseases of transgenic tobacco plants overexpressing sarcotoxin ia, a bactericidal peptide of insect. | sarcotoxin ia is a bactericidal peptide of 39 amino acids found in the common flesh fly, sarcophaga peregrina. many agronomically important bacteria in japan are killed by this peptide at sub-micro molar levels, and the growth of tobacco and rice suspension cultured cells is not inhibited with less than 25 microm. transgenic tobacco plants which overexpress the peptide, i.e. over 250 pmol per gram of fresh leaf, under the control of a high expression constitutive promoter showed enhanced resista ... | 1999 | 10050028 |
| identification and cloning of an erwinia carotovora subsp. carotovora bacteriocin regulator gene by insertional mutagenesis. | avirulent erwinia carotovora subsp. carotovora cge234-m403 produces two types of bacteriocin. for the purpose of cloning the bacteriocin genes of strain cge234m403, a spontaneous rifampin-resistant mutant of this strain, m-rif-11-2, was isolated. by tn5 insertional mutagenesis using m-rif-11-2, a mutant, tm01a01, which produces the high-molecular-weight bacteriocin but not the low-molecular-weight bacteriocin was obtained. by thermal asymmetric interlaced pcr, the dna sequence from the tn5 inser ... | 1999 | 10074096 |
| kdgrecc negatively regulates genes for pectinases, cellulase, protease, harpinecc, and a global rna regulator in erwinia carotovora subsp. carotovora. | erwinia carotovora subsp. carotovora produces extracellular pectate lyase (pel), polygalacturonase (peh), cellulase (cel), and protease (prt). the concerted actions of these enzymes largely determine the virulence of this plant-pathogenic bacterium. e. carotovora subsp. carotovora also produces harpinecc, the elicitor of the hypersensitive reaction. we document here that kdgrecc (kdg, 2-keto-3-deoxygluconate; kdgr, general repressor of genes involved in pectin and galacturonate catabolism), a ho ... | 1999 | 10198003 |
| a pyruvated mannose-specific xanthan lyase involved in xanthan degradation by paenibacillus alginolyticus xl-1. | the xanthan-degrading bacterium paenibacillus alginolyticus xl-1, isolated from soil, degrades approximately 28% of the xanthan molecule and appears to leave the backbone intact. several xanthan-degrading enzymes were excreted during growth on xanthan, including xanthan lyase. xanthan lyase production was induced by xanthan and inhibited by glucose and low-molecular-weight enzymatic degradation products from xanthan. a xanthan lyase with a molecular mass of 85 kda and a pi of 7.9 was purified an ... | 1999 | 10347025 |
| influence of soft rot bacteria on growth of listeria monocytogenes on potato tuber slices. | growth of listeria monocytogenes on potato tuber slices and its interaction with four representative species of soft rot bacteria (pseudomonas fluorescens, p. viridiflava, erwinia carotovora subsp. carotovora, and xanthomonas campestris) were investigated. when potato tuber slices were inoculated with one of two l. monocytogenes strains (scott a and atcc 15313), an increase in numbers of 3 to 4 logs per gram of tissue was observed with samples that were stored at 20 degrees c for 6 days. however ... | 1999 | 10419206 |
| purification of catechol siderophores by boronate affinity chromatography: identification of chrysobactin from erwinia carotovora subsp. carotovora. | catechols are co-planar cis-diols known to form stable, isolable complexes with borate under weakly basic conditions. we exploited this chemistry and developed a boronate affinity chromatography for isolating catechol siderophores. the method was applied to the isolation of chrysobactin, enterobactin, and an unknown catechol siderophore produce by erwinia carotovora subsp. carotovora w3c105. yields of chrysobactin and enterobactin purified by boronate affinity chromatography were at least two-fo ... | 1999 | 10420578 |
| development and application of pathovar-specific monoclonal antibodies that recognize the lipopolysaccharide o antigen and the type iv fimbriae of xanthomonas hyacinthi. | the objective of this study was to develop a specific immunological diagnostic assay for yellow disease in hyacinths, using monoclonal antibodies (mabs). mice were immunized with a crude cell wall preparation (shear fraction) from xanthomonas hyacinthi and with purified type iv fimbriae. hybridomas were screened for a positive reaction with x. hyacinthi cells or fimbriae and for a negative reaction with x. translucens pv. graminis or erwinia carotovora subsp. carotovora. nine mabs recognized fim ... | 1999 | 10473431 |
| the response regulator expm is essential for the virulence of erwinia carotovora subsp. carotovora and acts negatively on the sigma factor rpos (sigma s). | the main virulence factors of erwinia carotovora subsp. carotovora, the secreted, extracellular cell-wall-degrading enzymes, are controlled by several regulatory mechanisms. we have isolated transposon mutants with reduced virulence on tobacco. one of these mutants, with a mutation in a gene designated expm, was characterized in this study. this mutant produces slightly reduced amounts of extracellular enzymes in vitro and the secretion of the enzymes is also affected. the expm wild-type allele ... | 1999 | 10478478 |
| rsmc of the soft-rotting bacterium erwinia carotovora subsp. carotovora negatively controls extracellular enzyme and harpin(ecc) production and virulence by modulating levels of regulatory rna (rsmb) and rna-binding protein (rsma). | previous studies have shown that the production of extracellular enzymes (pectate lyase [pel], polygalacturonase [peh], cellulase [cel], and protease [prt]) and harpin(ecc) (the elicitor of hypersensitive reaction) in erwinia carotovora subsp. carotovora is regulated by rsma, an rna-binding protein, and rsmb, a regulatory rna (rsm stands for regulator of secondary metabolites) (y. liu et al., mol. microbiol. 29:219-234, 1998). we have cloned and characterized a novel regulatory gene, rsmc, that ... | 1999 | 10498717 |
| the phytopathogenic bacteria erwinia carotovora infects drosophila and activates an immune response. | although drosophila possesses potent immune responses, little is known about the microbial pathogens that infect drosophila. we have identified members of the bacterial genus erwinia that induce the systemic expression of genes encoding antimicrobial peptides in drosophila larvae after ingestion. these erwinia strains are phytopathogens and use flies as vectors; our data suggest that these strains have also evolved mechanisms for exploiting their insect vectors as hosts. erwinia infections induc ... | 2000 | 10725405 |
| quorum sensing in the plant pathogen erwinia carotovora subsp. carotovora: the role of expr(ecc). | the production of the main virulence determinants of the plant pathogen erwinia carotovora subsp. carotovora, the extracellular cell wall-degrading enzymes, is partly controlled by the diffusible signal molecule n-(3-oxohexanoyl)-l-homoserine lactone (ohhl). ohhl is synthesized by the product of the expi/cari gene. linked to expi we found a gene encoding a putative transcriptional regulator of the luxr-family. this gene, expr(ecc), is transcribed convergently to the expi gene and the two open re ... | 2000 | 10755301 |
| interacting signal pathways control defense gene expression in arabidopsis in response to cell wall-degrading enzymes from erwinia carotovora. | we have characterized the role of salicylic acid (sa)-independent defense signaling in arabidopsis thaliana in response to the plant pathogen erwinia carotovora subsp. carotovora. use of pathway-specific target genes as well as signal mutants allowed us to elucidate the role and interactions of ethylene, jasmonic acid (ja), and sa signal pathways in this response. gene expression studies suggest a central role for both ethylene and ja pathways in the regulation of defense gene expression trigger ... | 2000 | 10755306 |
| a two-component regulatory system, pehr-pehs, controls endopolygalacturonase production and virulence in the plant pathogen erwinia carotovora subsp. carotovora. | genes coding for the main virulence determinants of the plant pathogen erwinia carotovora subsp. carotovora, the plant cell wall-degrading enzymes, are under the coordinate control of global regulator systems including both positive and negative factors. in addition to this global control, some virulence determinants are subject to specific regulation. we have previously shown that mutations in the pehr locus result in reduced virulence and impaired production of one of these enzymes, an endopol ... | 2000 | 10755308 |
| increased killing of bacillus subtilis on the hair roots of transgenic t4 lysozyme-producing potatoes. | transgenic potato plants expressing the phage t4 lysozyme gene which are resistant to the plant-pathogenic enterobacterium erwinia carotovora subsp. carotovora have been constructed. the agricultural growth of these potatoes might have harmful effects on soil microbiota as a result of t4 lysozyme release into the rhizosphere. to assess the bactericidal effect of roots, we have developed a novel method to associate the cells of bacillus subtilis with hair roots of plants and to quantify the survi ... | 2000 | 10788351 |
| prey range characterization, ribotyping, and diversity of soil and rhizosphere bdellovibrio spp. isolated on phytopathogenic bacteria. | thirty new bdellovibrio strains were isolated from an agricultural soil and from the rhizosphere of plants grown in that soil. using a combined molecular and culture-based approach, we found that the soil bdellovibrios included subpopulations of organisms that differed from rhizosphere bdellovibrios. thirteen soil and seven common bean rhizosphere bdellovibrio strains were isolated when pseudomonas corrugata was used as prey; seven and two soil strains were isolated when erwinia carotovora subsp ... | 2000 | 10831412 |
| induced expression of sarcotoxin ia enhanced host resistance against both bacterial and fungal pathogens in transgenic tobacco. | we demonstrate here that induced expression of sarcotoxin ia, a bactericidal peptide from sarcophaga peregrina, enhanced the resistance of transgenic tobacco plants to both bacterial and fungal pathogens. the peptide was produced with a modified pr1a promoter, which is further activated by salicylic acid treatment and necrotic lesion formation by pathogen infection. host resistance to infection of bacteria erwinia carotovora subsp. carotovora and pseudomonas syringae pv. tabaci was shown to be d ... | 2000 | 10939257 |
| linear beta-1,3 glucans are elicitors of defense responses in tobacco. | laminarin, a linear beta-1,3 glucan (mean degree of polymerization of 33) was extracted and purified from the brown alga laminaria digitata. its elicitor activity on tobacco (nicotiana tabacum) was compared to that of oligogalacturonides with a mean degree of polymerization of 10. the two oligosaccharides were perceived by suspension-cultured cells as distinct chemical stimuli but triggered a similar and broad spectrum of defense responses. a dose of 200 microg ml(-1) laminarin or oligogalacturo ... | 2000 | 11080280 |
| molecular characterization of global regulatory rna species that control pathogenicity factors in erwinia amylovora and erwinia herbicola pv. gypsophilae. | rsmb(ecc) specifies a nontranslatable rna regulator that controls exoprotein production and pathogenicity in soft rot-causing erwinia carotovora subsp. carotovora. this effect of rsmb(ecc) rna is mediated mostly by neutralizing the function of rsma(ecc), an rna-binding protein of e. carotovora subsp. carotovora, which acts as a global negative regulator. to determine the occurrence of functional homologs of rsmb(ecc) in non-soft-rot-causing erwinia species, we cloned the rsmb genes of e. amylovo ... | 2001 | 11222584 |
| effects of the two-component system comprising gaca and gacs of erwinia carotovora subsp. carotovora on the production of global regulatory rsmb rna, extracellular enzymes, and harpinecc. | posttranscriptional regulation mediated by the regulator of secondary metabolites (rsm) rsma-rsmb pair is the most important factor in the expression of genes for extracellular enzymes and harpinecc in erwinia carotovora subsp. carotovora. rsma is a small rna-binding protein, which acts by lowering the half-life of a mrna species. rsmb specifies an untranslated regulatory rna and neutralizes the rsma effect. it has been speculated that gaca-gacs, members of a two-component system, may affect gen ... | 2001 | 11310739 |
| global regulators expa (gaca) and kdgr modulate extracellular enzyme gene expression through the rsma-rsmb system in erwinia carotovora subsp. carotovora. | the production of the main virulence determinants, the extracellular plant cell wall-degrading enzymes, and hence virulence of erwinia carotovora subsp. carotovora is controlled by a complex regulatory network. one of the global regulators, the response regulator expa, a gaca homolog, is required for transcriptional activation of the extracellular enzyme genes of this soft-rot pathogen. to elucidate the mechanism of expa control as well as interactions with other regulatory systems, we isolated ... | 2001 | 11497464 |
| type iii secretion contributes to the pathogenesis of the soft-rot pathogen erwinia carotovora: partial characterization of the hrp gene cluster. | the virulence of soft-rot erwinia species is dependent mainly upon secreted enzymes such as pectinases, pectin lyases, and proteases that cause maceration of plant tissue. some soft-rot erwinia spp. also harbor genes homologous to the hypersensitive reaction and pathogenesis (hrp) gene cluster, encoding components of the type iii secretion system. the hrp genes are essential virulence determinants for numerous nonmacerating gram-negative plant pathogens but their role in the virulence of soft-ro ... | 2001 | 11497468 |
| analysis of native microflora and selection of strains antagonistic to human pathogens on fresh produce. | the native microflora of three types of produce (green bell peppers, romaine lettuce, and prepeeled baby carrots) and two types of sprouting seeds (alfalfa and clover) were investigated. aerobic plate count (apc) for each produce or seed type as determined on pseudomonas agar f (paf) with incubation at 28 degrees c was in the range of 4 to 7 log cfu per g of tissue or seed. there was no significant difference (p > or = 0.05) in apc when the determinations were made with three agar media includin ... | 2001 | 11510644 |
| dna inversion in the tail fiber gene alters the host range specificity of carotovoricin er, a phage-tail-like bacteriocin of phytopathogenic erwinia carotovora subsp. carotovora er. | carotovoricin er is a phage-tail-like bacteriocin produced by erwinia carotovora subsp. carotovora strain er, a causative agent for soft rot disease in plants. here we studied binding and killing spectra of carotovoricin er preparations for various strains of the bacterium (strains 645ar, ec-2, n786, and p7) and found that the preparations contain two types of carotovoricin er with different host specificities; carotovoricin era possessing a tail fiber protein of 68 kda killed strains 645ar and ... | 2001 | 11591670 |
| genotyping of bacteria belonging to the former erwinia genus by pcr-rflp analysis of a reca gene fragment. | genotypic characterization, based on the analysis of restriction fragment length polymorphism of the reca gene fragment pcr product (reca pcr-rflp), was performed on members of the former erwinia genus. pcr primers deduced from published reca gene sequences of erwinia carotovora allowed the amplification of an approximately 730 bp dna fragment from each of the 19 erwinia species tested. amplified reca fragments were compared using rflp analysis with four endonucleases (alui, hinfi, tasi and tru1 ... | 2002 | 11832521 |