| specific interactions of erwinia chrysanthemi kdgr repressor with different operators of genes involved in pectinolysis. | the erwinia chrysanthemi kdgr gene encodes a repressor that negatively regulates the expression of genes involved in pectinolysis and in pectinase secretion. the cloned kdgr gene was overexpressed in escherichia coli by using a phage t7 system. overproduced repressor was purified to homogeneity by two chromatographic steps. gel retardation and dnase i protection experiments demonstrated the specific binding of the kdgr protein to the operators of pectinase genes (pela, pelb, pelc, pele), to the ... | 1994 | 8107132 |
| role of endoglucanases in erwinia chrysanthemi 3937 virulence on saintpaulia ionantha. | the role of endoglucanases (endoglucanases z and y) in erwinia chrysanthemi pathogenicity on saintpaulia ionantha was assessed by mutagenizing cloned cel genes (celz and cely) and recombining them with the chromosomal alleles. strains with an omega interposon in celz, a deletion in cely, or a double cel mutant were as virulent as the wild-type strain. however, in the strain with a deletion in cely, a delay in the appearance of symptoms was observed, and then maceration progressed as in plants in ... | 1994 | 8113196 |
| diabetes mellitus and pancreatitis as a complication of l-asparaginase therapy. | | 1993 | 8132268 |
| a carboxyl-terminal four-amino acid motif is required for secretion of the metalloprotease prtg through the erwinia chrysanthemi protease secretion pathway. | prtg is an extracellular metalloprotease secreted by the gram-negative bacterium erwinia chrysanthemi through a signal peptide-independent secretion pathway. previous studies showed that the prtg secretion signal is cooh-terminal and located in the last 56 residues of prtg. we have now performed a deletion and elongation mapping of a short secretion competent cooh-terminal peptide cterg. this approach allowed us to show that: (i) the smaller cooh-terminal sequence containing the information nece ... | 1994 | 8132636 |
| molecular analysis of the erwinia chrysanthemi region containing the kdga and zwf genes. | the pathways of pectin and galacturonate catabolism in erwinia chrysanthemi converge to form a common intermediate, 2-keto-3-deoxygluconate, which is phosphorylated to form 2-keto-3-deoxy-6-phosphogluconate (kdgp) and then cleaved by the aldolase encoded by the kdga gene. we cloned the kdga gene of the e. chrysanthemi strain 3937 by complementing an escherichia coli kdga mutation, using an rp4-derivative plasmid. restriction mapping of the kdga region and isolation of kdga-lac fusions allowed th ... | 1994 | 8145647 |
| acute parotitis during induction therapy including l-asparaginase in acute lymphoblastic leukemia. | in a patient affected by acute lymphoblastic leukemia (all) and subjected to therapy with erwinia l-asparaginase, acute parotitis was observed. microbiological studies excluded any infectious etiology. regression of parotitis was spontaneous. this complication has not been previously reported and could be due to the same mechanism of pancreatic injury. the occurrence of acute parotitis needs to be promptly recognized in order to avoid the continuation of l-asparaginase. | 1994 | 8148421 |
| periplasmic disulphide bond formation is essential for cellulase secretion by the plant pathogen erwinia chrysanthemi. | secretion to the cell exterior of cellulase egz and of at least six pectinases enables the gram-negative erwinia chrysanthemi to cause severe plant disease. the c-terminal cellulose-binding domain (cbd) of egz was found to contain a disulphide bond which forms, in the periplasm, between residues cys-325 and cys-382. dithiothreitol (dtt)-treatment of native egz showed that the disulphide bond was dispensable, both for catalysis and cellulose binding. adding dtt to e. chrysanthemi cultures led to ... | 1994 | 8152378 |
| molecular characterization of the erwinia chrysanthemi kdgk gene involved in pectin degradation. | the pathways of pectin and galacturonate catabolism in erwinia chrysanthemi converge to form a common intermediate, 2-keto-3-deoxygluconate (kdg), which is phosphorylated by kdg kinase encoded by the kdgk gene. we cloned the kdgk gene of e. chrysanthemi 3937 by complementing an escherichia coli kdgk mutation, using an rp4-derivative plasmid. one of the kdgk r-prime plasmids harbored a dna insert of about 80 kb and carried the uxua and uxub genes involved in glucuronate catabolism and the cely ge ... | 1994 | 8157608 |
| piv, a filamentous phage protein that mediates phage export across the bacterial cell envelope, forms a multimer. | filamentous phage piv is an outer membrane protein required for phage assembly and secretion. chemical cross-linking and sedimentation experiments have been used to demonstrate that piv from f1-infected escherichia coli exists as a homo-multimer, probably composed of 10 to 12 subunits. piv secreted from spheroplasts remains soluble and does not form multimers. synthesis of piv from distantly related filamentous phages or from a bacterial homolog that participates in a specialized form of extra-c ... | 1994 | 8158648 |
| characterization of dsbc, a periplasmic protein of erwinia chrysanthemi and escherichia coli with disulfide isomerase activity. | we identified and characterized an erwinia chrysanthemi gene able to complement an escherichia coli dsba mutation that prevents disulfide bond formation in periplasmic proteins. this gene, dsbc, codes for a 24 kda periplasmic protein that contains a characteristic active site sequence of disulfide isomerases, phe-x-x-x-x-cys-x-x-cys. besides the active site, dsbc has no homology with dsba, thioredoxin or eukaryotic protein disulfide isomerase and it could define a new subfamily of disulfide isom ... | 1994 | 8168497 |
| fermentative production and isolation of l-asparaginase from erwinia carotovora, ec-113. | l-asparaginase, an enzyme-drug used for the treatment of acute lymphoblastic leukemia was isolated from erwinia carotovora. the effects of different carbon and nitrogen sources on the fermentative production of the enzyme were studied. lactose, monosodium glutamate, corn steep liquor, tryptone and yeast extract showed significant stimulation of the production. when l-asparagine (0.2%), a substrate of the enzyme was added to a fermentation medium, a mutant strain ec-113 exhibited 6 times higher p ... | 1993 | 8181956 |
| c-terminal secretion signal of an erwinia chrysanthemi protease secreted by a signal peptide-independent pathway: proton nmr and cd conformational studies in membrane-mimetic environments. | the detailed structure of a 68-residue chimeric peptide encompassing the 56 last c-terminal residues of erwinia chrysanthemi protease g has been investigated by using circular dichroism and nmr spectroscopies. the peptide which contains the secretion signal of prtg was solubilized either in aqueous solvent, in trifluoroethanol (tfe)/h2o mixtures, or in dodecyl beta-d-maltoside detergent. the peptide helical content increases upon tfe and detergent additions. a stable conformation is reached at 4 ... | 1994 | 8204613 |
| characterization of the prta and prtb genes of erwinia chrysanthemi ec16. | two tandem metalloprotease-encoding structural genes, prta and prtb, were sequenced from erwinia chrysanthemi ec16. these were highly homologous to previously reported genes from the same bacteria, as well as to three other metalloprotease-encoding genes from enteric bacteria. the three tandem prt structural genes from strain ec16 were closely linked to a cluster of genes previously found to be essential for extracellular secretion of the metalloproteases. | 1993 | 8224883 |
| identification of two components of the serratia marcescens metalloprotease transporter: protease sm secretion in escherichia coli is tolc dependent. | the serratia marcescens metalloprotease (protease sm) belongs to a family of proteins secreted from gram-negative bacteria by a signal peptide-independent pathway which requires a specific transporter consisting of three proteins: two in the inner membrane and one in the outer membrane. the prtdsm and prtesm genes encoding the two s. marcescens inner membrane components were cloned and expressed in escherichia coli. their nucleotide sequence revealed high overall homology with the two analogous ... | 1993 | 8226679 |
| on a (beta-) roll. | | 1993 | 8236448 |
| molecular analysis of the major cellulase (celv) of erwinia carotovora: evidence for an evolutionary "mix-and-match" of enzyme domains. | the structural gene for the major cellulase of erwinia carotovora subspecies carotovora (ecc) was isolated and expressed in escherichia coli. sequencing of the gene (celv) revealed a typical signal sequence and two functional domains in the enzyme; a catalytic domain linked by a short proline/threonine-rich linker to a cellulose-binding domain (cbd). the deduced amino acid sequence of the catalytic domain showed homology with cellulases of family a, including enzymes from bacillus spp. and erwin ... | 1993 | 8246888 |
| uptake of galacturonic acid in erwinia chrysanthemi ec16. | uptake of [14c]galacturonic acid in erwinia chrysanthemi was found to be stimulated during growth on pectin and its degradation products, saturated digalacturonic acid and galacturonic acid. cells isolated from macerated potato tissue also showed increased levels of uptake activity for this molecule compared with those showed by glycerol-grown cells. uptake was found to be an active process, and it displayed saturation kinetics. an escherichia coli galacturonic acid transport mutant harboring th ... | 1993 | 8320243 |
| 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 |
| characterization of the nucm gene coding for a nuclease of the phytopathogenic bacteria erwinia chrysanthemi. | the gene nucm encoding a nuclease was cloned from a genomic library of erwinia chrysanthemi. the nucm gene was subcloned, and mutagenized by insertion of a uida-kanr cartridge. this mutation was introduced by recombination into the erwinia chrysanthemi chromosome. the nucm mutant lost nucm activity when tested on a dna plate after 24 hours, but still possessed secondary weak nuclease activity. the nucleotide sequence of nucm was determined. it presents a 798 bp open reading frame, coding for a 2 ... | 1993 | 8332061 |
| a left-handed crossover involved in amidohydrolase catalysis. crystal structure of erwinia chrysanthemi l-asparaginase with bound l-aspartate. | the crystal structure of l-asparaginase from erwinia chrysanthemi in the presence and absence of l-aspartate was determined at 1.8 a resolution. conserved residues in a left-handed crossover (a rare occurrence in protein structures) link pairs of dimers into the catalytically active tetrameric form of the enzyme. the structure of era containing bound aspartic acid shows that this unusual strand connectivity is an essential part of the active site architecture, responsible for releasing the produ ... | 1993 | 8348975 |
| sequence homology between a bacterial metalloproteinase and eukaryotic matrix metalloproteinases. | the origin and evolution of matrix metalloproteinases represent an exciting subject of study. recently, various reports have searched for a relationship between bacterial and eukaryotic metalloproteinases. in this report, we constructed a phylogenetic tree using the amino acid sequence of one bacterial metalloproteinase and eight eukaryotic matrix metalloproteinases and performed multiple alignments with some of these sequences. we concluded that there is a familial relationship between members ... | 1993 | 8350353 |
| structure of an extracellular polysaccharide produced by erwinia chrysanthemi. | erwinia chrysanthemi pv zeae strain sr260, a phytopathogen of corn, produced from lactose an acidic extracellular polysaccharide which was purified and found to consist of l-rhamnose, d-mannose, d-glucose, and d-glucuronic acid in the ratio of 3:1:1:1. a combination of chemical (carboxyl-group reduction, methylation analysis, periodate oxidation, smith degradation, and lithium-ethylenediamine degradation) and physical (1 and 2d nmr spectroscopy) methods revealed that the polysaccharide is compos ... | 1993 | 8370026 |
| characterization and overexpression of the pem gene encoding pectin methylesterase of erwinia chrysanthemi strain 3937. | the pem gene encoding the pectin methylesterase (pme) of erwinia chrysanthemi strain 3937 was subcloned and its nucleotide sequence determined. the gene contains an open reading frame of 1098 bp and codes for a protein of 366 amino acids (aa). the mature 37-kda form of the protein is 342 aa long and has a calculated isoelectric point of 9.64. a plasmid was constructed to overproduce pme: a dna fragment carrying pem was amplified by the polymerase chain reaction and cloned downstream from the pl ... | 1993 | 8370537 |
| [expression of pel genes of erwinia chrysanthemi ena49 in erwinia carotovora var. atroseptica 36a cells]. | erwinia atroseptica 36a cells were transformed by the recombinant plasmid ppl5-1 (a derivative of the vector plasmid puc19) containing pelb and pelc genes which encode pectate lyases of erwinia chrysanthemi ena49. synthesis of pectate lyases plb and plc determined by the cloned pel genes is constitutive in erwinia atroseptica 36appl5-1 cells and not inducible by sodium polypectate. the major part of these enzymes was accumulated in the periplasmic fraction of erwinia atroseptica and cells were u ... | 1993 | 8371722 |
| 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 |
| involvement of lipopolysaccharide in the secretion of escherichia coli alpha-haemolysin and erwinia chrysanthemi proteases. | the presence of the alpha-haemolysin secretion genes sensitizes escherichia coli to vancomycin, a glycopeptide antibiotic that is normally excluded from the gram-negative envelope (owing to its large size) (m(r) 1400). the selection of vancomycin mutants in strains carrying such genes was found to be a very powerful method for selecting non-haemolytic mutants. in this way, mutations in the known secretion genes, hlyb, hlyd and tolc, were obtained. however additional mutations mapped in genes rfa ... | 1993 | 8437516 |
| regulation of the expression of a pela::uida fusion in erwinia chrysanthemi and demonstration of the synergistic action of plant extract with polygalacturonate on pectate lyase synthesis. | the phytopathogenicity of erwinia chrysanthemi is chiefly supported by the production of pectate lyase isoenzymes, encoded by the pel genes. one of these enzymes, pela, encoded by the pela gene, seems to represent only a small part of the total pectate lyase activity, but is required for full bacterial pathogenicity. to study the regulation of pela gene expression, a pela::uida gene fusion was constructed. expression of this fusion was analysed under various growth conditions and in various gene ... | 1993 | 8450303 |
| mutagenesis of cellulase egz for studying the general protein secretory pathway in erwinia chrysanthemi. | extracellular secretion of endoglucanase z (egz) from erwinia chrysanthemi is mediated by the so-called out general secretion pathway and, presumably, involves recognition of egz-carried structural information by one or more of the out proteins. investigating the relationships between structure and secretability of egz was the purpose of the present work. egz is made of two independent domains, located at the n- and c-proximal sides, separated by a ser/thr-rich region, which are responsible for ... | 1993 | 8469118 |
| autoregulation of carbapenem biosynthesis in erwinia carotovora by analogues of n-(3-oxohexanoyl)-l-homoserine lactone. | n-(3-oxohexanoyl)-l-homoserine lactone (hsl) (i) is the autoregulator controlling carbapenem antibiotic biosynthesis in erwinia carotovora atcc 39048. the chemical synthesis and biological evaluation of analogues of hsl are described. these include alterations of chirality, side-chain modifications, ring size and ring hetero atom. a number of compounds are reported which are capable of restoring the phenotype to a hsl negative mutant but at higher concentrations than hsl. a-factor, the autoregul ... | 1993 | 8478262 |
| new domain motif: the structure of pectate lyase c, a secreted plant virulence factor. | pectate lyases are secreted by pathogens and initiate soft-rot diseases in plants by cleaving polygalacturonate, a major component of the plant cell wall. the three-dimensional structure of pectate lyase c from erwinia chrysanthemi has been solved and refined to a resolution of 2.2 angstroms. the enzyme folds into a unique motif of parallel beta strands coiled into a large helix. within the core, the amino acids form linear stacks and include a novel asparagine ladder. the sequence similarities ... | 1993 | 8502994 |
| 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 |
| the lux autoinducer regulates the production of exoenzyme virulence determinants in erwinia carotovora and pseudomonas aeruginosa. | erwinia carotovora and pseudomonas aeruginosa secrete exoenzymes that contribute to the pathogenesis of plant and mammalian infections respectively. e.carotovora mutants defective in synthesis of the pectinase, cellulase and protease exoenzymes were isolated and classified into two groups. group 2 mutants were found to be defective in the production of a small freely diffusible molecule, n-3-(oxohexanoyl)-l-homoserine, lactone (hsl), and were avirulent. addition of exogenous hsl to these group 2 ... | 1993 | 8508773 |
| characterization of the erwinia chrysanthemi osmoprotectant transporter gene ousa. | growth of erwinia chrysanthemi in media of elevated osmolarity can be achieved by the uptake and accumulation of various osmoprotectants. this study deals with the cloning and sequencing of the ousa gene-encoded osmoprotectant uptake system a from e. chrysanthemi 3937. ousa belongs to the superfamily of solute ion cotransporters. this osmotically inducible system allows the uptake of glycine betaine, proline, ectoine, and pipecolic acid and presents strong similarities in nucleotide sequence and ... | 1996 | 8550465 |
| the extreme c-terminus is required for secretion of both the native polygalacturonase (peha) and peha-bla hybrid proteins in erwinia carotovora subsp. carotovora. | a set of gene fusions was constructed between the peha gene encoding the secreted endopolygalacturonase (peha) and the bla gene coding for a normally periplasmic beta-lactamase (bla). the resulting hybrid proteins were specifically and actively routed out of the cells via the out-terminal branch of the general secretory pathway (gsp) in erwinia carotovora subsp. carotovora (ecc), provided that no more than the last two amino acids (aa) of the peha domain were excluded from the fusion. however, b ... | 1995 | 8559064 |
| polymerase chain reaction for verification of fluorescent colonies of erwinia chrysanthemi and pseudomonas putida wcs358 in immunofluorescence colony staining. | the potential of polymerase chain reaction (pcr) for verifying the identity of colonies stained by the immunofluorescence colony-staining (ifc) procedure was investigated. using primers directed against conserved sequences of the pectate lyase-genes coding for isozymes pla, pld and ple of erwinia chrysanthemi, the authors confirmed the identity of 96% of 20 fluorescent target colonies, punched from ifc-stained samples with pure cultures. in pour plates with mixtures of erw. chrysanthemi and non- ... | 1995 | 8567494 |
| analysis of the erwinia chrysanthemi ferrichrysobactin receptor gene: resemblance to the escherichia coli fepa-fes bidirectional promoter region and homology with hydroxamate receptors. | the fct cbsceba operon from the erwinia chrysanthemi 3937 chrysobactin-dependent iron assimilation system codes for transport and biosynthetic functions. the sequence of the fct outer membrane receptor gene was determined. the fct promoter region displays a strong resemblance to the escherichia coli bidirectional intercistronic region controlling the expression of the fepa-entd and fes-entf operons. an apparent fur-binding site was shown to confer iron regulation on an fct::lac fusion expressed ... | 1996 | 8576065 |
| characterization of the pell gene encoding a novel pectate lyase of erwinia chrysanthemi 3937. | erwinia chrysanthemi 3937 secretes five major isoenzymes of pectate lyases encoded by the pela, pelb, pelc, peld and pele genes. recently, a new set of pectate lyases was identified in e. chrysanthemi mutants deleted of those pel genes. we cloned the pell gene, encoding one of these secondary pectate lyases of e. chrysanthemi 3937, from a genomic bank of a strain deleted of the five major pel genes. the nucleotide sequence of the region containing the pell gene was determined. the pell reading f ... | 1995 | 8577252 |
| erwinia chrysanthemi harpinech: an elicitor of the hypersensitive response that contributes to soft-rot pathogenesis. | mutants of the soft-rot pathogen erwinia chrysanthemi ec16 that are deficient in the production of the pectate lyase isozymes pelabce can elicit the hypersensitive response (hr) in tobacco leaves. the hrpnech gene was identified in a collection of cosmids carrying e. chrysanthemi hrp genes by its hybridization with the erwinia amylovora hrpnea gene. hrpnech appears to be in a monocistronic operon, and it encodes a predicted protein of 340 amino acids that is glycine-rich, lacking in cysteine, an ... | 1995 | 8589405 |
| 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 |
| differential expression of two siderophore-dependent iron-acquisition pathways in erwinia chrysanthemi 3937: characterization of a novel ferrisiderophore permease of the abc transporter family. | in planta expression of a high-affinity iron-uptake system involving the siderophore chrysobactin in erwinia chrysanthemi 3937 contributes greatly to invasive growth of this pathogen on its natural host, african violets. a previous study reported that global regulation by iron in this strain was mediated at the transcriptional level via the cbr locus which, when inactivated by insertional mutation, prevents the chrysobactin system from being tightly repressed by fecl3. herein, we report the nucl ... | 1995 | 8596459 |
| genetic organization of a dna-processing region required for mobilization of a non-self-transmissible plasmid, pec3, isolated from erwinia carotovora subsp. carotovora. | a non-self-transmissible multiple-copy plasmid, pec3, isolated from the phytopathogenic bacterium, erwinia carotovora subsp. carotovora, can be mobilized by an incp-type plasmid. the hybrid plasmid vector, petc3, constructed from pec3 by fusion to markers conferring tcr and cmr, was transferred by conjugation from escherichia coli (ec) to various genera of enterobacteriaceae and to other genera of gram(-) bacteria which included xanthomonas, agrobacterium and rhizobium. deletion analysis and suc ... | 1996 | 8621089 |
| the erwinia chrysanthemi pect gene regulates pectinase gene expression. | a new type of erwinia chrysanthemi mutant displaying a derepressed synthesis of pectate lyase was isolated. the gene mutated in these strains, pect, encodes a 316-amino-acid protein with a size of 34,761 da that belongs to the lysr family of transcriptional activators and presents 61% identity with the e. coli protein lrha. pect represses the expression of pectate lyase genes pelc, peld, pele, pell, and kdgc, activates pelb, and has no effect on the expression of pela or the pectin methylesteras ... | 1996 | 8626286 |
| purification and functional characterization of pecs, a regulator of virulence-factor synthesis in erwinia chrysanthemi. | the erwinia chrysanthemi pecs gene encodes a repressor that negatively regulates the expression of virulence factors such as pectinases or cellulases. the cloned pecs gene was overexpressed using a phage t7 system. the purification of pecs involved deae-anion exchange and tsk-heparin columns and delivered the pecs protein that was purified to homogeneity. the purified repressor displayed an 18 kda apparent molecular mass and an isoelectric point near to neutrality (pl = 6.5). gel-filtration expe ... | 1996 | 8733237 |
| hemostasis in childhood acute lymphoblastic leukemia: coagulopathy induced by disease and treatment. | thromboembolic events (te) are serious complications of treatment for childhood acute lymphoblastic leukemia (all) that result in significant morbidity and occasionally mortality. these events are strongly associated with the administration of l'asparaginase (asp). there have been many studies reporting te and assessing the coagulopathy associated with treatment. the intention of these studies was to determine a potential mechanism for thrombosis. this article reviews the current literature in t ... | 1995 | 8747702 |
| characterization of erwinia chrysanthemi by pectinolytic isozyme polymorphism and restriction fragment length polymorphism analysis of pcr-amplified fragments of pel genes. | conserved regions about 420 bp long of the pelade cluster specific to erwinia chrysanthemi were amplified by pcr and used to differentiate 78 strains of e. chrysanthemi that were obtained from different hosts and geographical areas. no pcr products were obtained from dna samples extracted from other pectinolytic and nonpectinolytic species and genera. the pel fragments amplified from the e. chrysanthemi strains studied were compared by performing a restriction fragment length polymorphism (rflp) ... | 1996 | 8779560 |
| the role of iron in plant host-pathogen interactions. | iron is unlikely to be readily available in plant tissues for invading microorganisms. soft rot, caused by erwinia chrysanthemi strain 3937 on african violets, is a valuable model for studying the role of iron and its ligands in plant-pathogen interactions. these studies could lead to the development of new control strategies against microbial infections of plants. | 1996 | 8795159 |
| 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 |
| cloning and characterization of a xylanase gene from corn strains of erwinia chrysanthemi. | the gene encoding a 42-kda endoxylanase was cloned from erwinia chrysanthemi strain d1. sequencing of this gene, called xyna, showed that it encoded a primary protein product of 413 amino acids with an unusual and long (31 amino acid) leader peptide that was cleaved during secretion to the bacterial periplasm. this protein is distinct from xylanases in glycohydrolase families 10 and 11 and, instead, appears to be intermediate between families 5 and 30. the xyna gene is located downstream from a ... | 1996 | 8810080 |
| regulatory systems modulating the transcription of the pectinase genes of erwinia chrysanthemi are conserved in escherichia coli. | to depolymerize plant pectin, the phytopathogenic enterobacterium erwinia chrysanthemi produces five isoenzymes of pectate lyases encoded by the five genes pela, pelb, pelc, peld and pele. in er. chrysanthemi, all genes involved in pectin degradation are specifically controlled by the kdgr repressor and are induced in the presence of a pectin catabolic product, 2-keto-3-deoxygluconate (kdg). transcription of the pectinase genes is dependent on many environmental conditions. transcriptional fusio ... | 1996 | 8828230 |
| characterization of pectin methylesterase b, an outer membrane lipoprotein of erwinia chrysanthemi 3937. | the secretion of extracellular pectinases, among which there are least six isoenzymes of pectate lyase and one pectin methylesterase, allows the phytopathogenic bacterium erwinia chrysanthemi to degrade pectin. a gene coding for a novel pectin methylesterase has been cloned from an e. chrysanthemi strain 3937 gene library. this gene, pemb, codes for a 433-amino-acid protein. the pemb n-terminal region has the characteristics of lipoprotein signal sequences. we have shown that the pemb precursor ... | 1996 | 8830237 |
| synthesis of optically pure chrysobactin and immunoassay development. | chrysobactin (alpha-n-(2,3-dihydroxybenzoyl)-d-lysyl-l-serine), a siderophore that is essential for systemic virulence by plant pathogenic erwinia chrysanthemi, was synthesized with high diastereomeric purity. chrysobactin was prepared by coupling the n-hydroxysuccinimide ester of alpha-n-(2,3-dibenzyloxybenzoyl)-epsilon-n-cbz-d-lysine with l-serine benzyl ester followed by deprotection via hydrogenolysis. optically pure chrysobactin was obtained with 98% overall yield. a monoclonal antibody to ... | 1996 | 8837459 |
| complementation of deletion mutations in a cloned functional cluster of erwinia chrysanthemi out genes with erwinia carotovora out homologues reveals outc and outd as candidate gatekeepers of species-specific secretion of proteins via the type ii pathway. | the type ii or sec-dependent secretion system is used by diverse gram-negative bacteria for secretion of extracellular proteins. of the 12-15 proteins involved in secretion, the requirement for many has not been demonstrated and little is known about their functions in the secretion process. the plant pathogens erwinia chrysanthemi and erwinia carotovora secrete extra-cellular pectate lyases (pels) using the type ii or out pathway. however, these two bacteria cannot secrete pels encoded by heter ... | 1996 | 8861215 |
| differential effect of site-directed mutations in pelc on pectate lyase activity, plant tissue maceration, and elicitor activity. | oligonucleotide site-directed mutations were introduced into the pelc gene of erwinia chrysanthemi ec16 that directed single or double amino acid changes affecting disulfide linkages, calcium binding, catalysis, and protein folding. subsequent characterization of the purified pelc mutant proteins demonstrated that pectinolytic function involves amino acids located near the calcium binding site rather than those surrounding an invariant vwidh sequence. wild-type pelc and the tested mutant protein ... | 1996 | 8900122 |
| regulation of pectinolysis in erwinia chrysanthemi. | erwinia chrysanthemi is an enterobacterium that causes various plant diseases. its pathogenicity results from the secretion of pectinolytic enzymes responsible for the disorganization of the plant cell wall. the e. chrysanthemi strain 3937 produces two pectin methylesterases, at least seven pectate lyases, a polygalacturonase, and a pectin lyase. the extracellular degradation of the pectin leads to the formation of oligogalacturonides that are catabolized through an intracellular pathway. the pe ... | 1996 | 8905080 |
| comparison of extracellular polysaccharides of erwinia chrysanthemi spp. | two extracellular polysaccharides from strains of erwinia chrysanhemi ech 1 and 9, phytopathogens of potatoes, have been isolated and purified. both have similar compositions and other properties to that produced by strain sr 260, a phytopathogen of corn. these polysaccharides are composed of l-rhamnose, d-mannose, d-glucose, d-glucuronic acid in the ratio 3:1:1:1. initial structural aspects of these polysaccharides are reflected in the 600 mhz 1h nmr spectra and the products of partial acid hyd ... | 1996 | 8910063 |
| protein secretion in gram-negative bacteria: assembly of the three components of abc protein-mediated exporters is ordered and promoted by substrate binding. | one of the strategies used by gram-negative bacteria to secrete proteins across the two membranes which delimit the cells, is sec independent and dedicated to proteins lacking an n-terminal signal peptide. it depends on abc protein-mediated exporters, which consist of three cell envelope proteins, two inner membrane proteins, an atpase (the abc protein), a membrane fusion protein (mfp) and an outer membrane polypeptide. erwinia chrysanthemi metalloproteases b and c and serratia marcescens hemopr ... | 1996 | 8918458 |
| 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 |
| analysis of bacterial carbapenem antibiotic production genes reveals a novel beta-lactam biosynthesis pathway. | carbapenems are beta-lactam antibiotics which have an increasing utility in chemotherapy, particularly for nosocomial, multidrug-resistant infections. strain gs101 of the bacterial phytopathogen, erwinia carotovora, makes the simple beta-lactam antibiotic, 1-carbapen-2-em-3-carboxylic acid. we have mapped and sequenced the erwinia genes encoding carbapenem production and have cloned these genes into escherichia coli where we have reconstituted, for the first time, functional expression of the be ... | 1996 | 8939426 |
| regulation of pelz, a gene of the pelb-pelc cluster encoding a new pectate lyase of erwinia chrysanthemi 3937. | the phytopathogenic enterobacterium erwinia chrysanthemi 3937 produces five major and several secondary endo-pectate lyases encoded by the pel genes. most of these genes are arranged in clusters on the bacterial chromosome. the genomic region surrounding the pelb-pelc cluster was supposed to be involved in the regulation of pelb and pelc synthesis. we demonstrated that the variation of pelb expression resulted from the titration of a regulatory protein by the gene adjacent to pelc. this gene was ... | 1996 | 8955401 |
| reca relieves negative autoregulation of rdga, which specifies a component of the reca-rdg regulatory circuit controlling pectin lyase production in erwinia carotovora ssp. carotovora. | the production of pectin lyase (pnl) in erwinia carotovora ssp. carotovora strain 71 is induced by dna-damaging agents such as mitomycin c (mc). this induction requires functions of reca, rdga and rdgb genes. based upon sequence homology, rdga was predicted to encode a repressor and rdgb was presumed to specify a transcriptional activator. to elucidate the function of rdga, the gene has been over-expressed in escherichia coli, and the 30 kda product purified by ammonium-sulphate precipitation, h ... | 1996 | 8971712 |
| antibiotics and garlic clove extract--inhibitory agents of cell wall degrading enzymes. | four antibiotics were tested against erwinia causing soft rot of onion (allium cepa var. aggregatum) of which streptomycin sulphate 90% and tetracycline hydrochloride 10% (streptocycline) recorded the maximum inhibition zone of 27.66 mm. in the enzyme studies the maximum inhibition of pectinlyase (pl), polygalacturonase (pg) and protopectinase production was recorded by the same antibiotic. the antibiotics have a significant influence on the production and activity of cell wall degrading enzymes ... | 1995 | 8972140 |
| characterization of the agrobacterium vitis peha gene and comparison of the encoded polygalacturonase with the homologous enzymes from erwinia carotovora and ralstonia solanacearum. | dna sequencing of the agrobacterium vitis peha gene revealed a predicted protein with an m(r) of 58,000 and significant similarity to the polygalacturonases of two other plant pathogens, erwinia carotovora and ralstonia (= pseudomonas or burkholderia) solanacearum. sequencing of the n terminus of the peha protein demonstrated cleavage of a 34-amino-acid signal peptide from pre-peha. mature peha accumulated primarily in the periplasm of a. vitis and peha+ escherichia coli cells during exponential ... | 1997 | 8979363 |
| isolation and characterization of new c-terminal substitution mutations affecting secretion of polygalacturonase in erwinia carotovora ssp. carotovora. | an intact c-terminus was previously shown to be required for stability and secretion of the polygalacturonase (peha) in erwinia carotovora ssp. carotovora. here we have analyzed the effects of amino acid (aa) substitutions generated to five c-terminal positions of peha. conservation of two hydrophobic and one non-hydrophobic residue (v372, v374 and n371, respectively) was found to be essential for maintenance of the protein stability. as an exception, one of the mutants (v372g) did not show majo ... | 1997 | 9000526 |
| extracellular melibiose and fructose are intermediates in raffinose catabolism during fermentation to ethanol by engineered enteric bacteria. | contrary to general concepts of bacterial saccharide metabolism, melibiose (25 to 32 g/liter) and fructose (5 to 14 g/liter) accumulated as extracellular intermediates during the catabolism of raffinose (o-alpha-d-galactopyranosyl-1, 6-alpha-d-glucopyranosyl-beta-d-fructofuranoside) (90 g/liter) by ethanologenic recombinants of escherichia coli b, klebsiella oxytoca m5a1, and erwinia chrysanthemi ec16. both hydrolysis products (melibiose and fructose) were subsequently transported and further me ... | 1997 | 9068632 |
| immunomagnetic separation of erwinia carotovora subsp. atroseptica from potato peel extracts to improve detection sensitivity on a crystal violet pectate medium or by pcr. | immunomagnetic separation (ims) procedures for the selective separation of erwinia carotovora subsp. atroseptica from potato peel extract were optimized for the recovery of target and removal of non-target bacteria. a streptomycin-resistant strain of erw. carotovora subsp. atroseptica was used in combination with a crystal violet pectate (cvp) medium supplemented with 100 micrograms ml-1 of streptomycin to determine the recovery level of the target bacterium. recovery obtained with a polyclonal ... | 1996 | 9072520 |
| activation of the erwinia carotovora subsp. carotovora pectin lyase structural gene pnla: a role for rdgb. | the activation of pectin lyase (pnl) production in erwinia carotovora subsp. carotovora strain 71 occurs upon dna damage via a unique regulatory circuit involving reca, rdga and rdgb. in a similar pnl-inducible system reconstituted in escherichia coli, the rdgb product was found to activate the expression of pnla, the structural gene for pectin lyase. the kinetic data presented here also show that transcription of pnla followed that of rdgb in er. carotovora subsp. carotovora, indicating a tempo ... | 1997 | 9084157 |
| the general secretion pathway of erwinia carotovora subsp. carotovora: analysis of the membrane topology of outc and outf. | the out gene cluster of erwinia carotovora subsp. carotovora (ecc) encodes the proteins of the type ii or general secretory pathway (gsp) apparatus which is required for secretion of pectinase and cellulase. in this study, fusions between ecc out genes and the topology probe blam were constructed. the ability of out protein domains to export blam across the cytoplasmic membrane in both escherichia coli and the cognate host was utilized to confirm the computer-predicted cytoplasmic membrane topol ... | 1997 | 9084158 |
| l-asparagine-depletion: another opinion. | | 1997 | 9093736 |
| comparative analysis of the five major erwinia chrysanthemi pectate lyases: enzyme characteristics and potential inhibitors. | in erwinia chrysanthemi 3937, pectate lyase activity mainly results from the cumulative action of five major isoenzymes, pela to pele. comparison of their amino acid sequences revealed two families, pelb-c and pela-d-e. molecular cloning permitted expression of the different pel genes in escherichia coli and the isolation of each pel independently from the other isoenzymes. we used similar experimental conditions to overproduce and purify the five pels in a one-step chromatography method. we ana ... | 1997 | 9098045 |
| molecular cloning, characterization, and mutagenesis of a pel gene from pseudomonas syringae pv. lachyrmans encoding a member of the erwinia chrysanthemi pelade family of pectate lyases. | the pels gene from pseudomonas syringae pv. lachrymans 859 was cloned by heterologous expression in nonpectolytic p. syringae pv. syringae buvs1, using genomic dna libraries constructed with two novel broad-host-range cosmid vectors, pcpp34 and pcpp47. screening of p. syringae pv. syringae transconjugants for the ability to pit pectate media at ph 6.0 and 8.5 yielded several overlapping clones of the same dna region. ultrathin-layer isoelectric focusing gels, activity-stained with diagnostically ... | 1997 | 9100381 |
| 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 |
| the cyclic amp receptor protein is the main activator of pectinolysis genes in erwinia chrysanthemi. | the main virulence factors of the phytopathogenic bacterium erwinia chrysanthemi are pectinases that cleave pectin, a major constituent of the plant cell wall. although physiological studies suggested that pectinase production in erwinia species is subjected to catabolite repression, the direct implication of the cyclic amp receptor protein (crp) in this regulation has never been demonstrated. to investigate the role of crp in pectin catabolism, we cloned the e. chrysanthemi crp gene by compleme ... | 1997 | 9171393 |
| investigation of physicochemical changes to l-asparaginase during freeze-thaw cycling. | l-asparaginase derived from erwinia chrysanthemi which is being investigated as an alternative to e. coli for the treatment of lymphoblastic leukaemia has been found in our laboratory to lose activity upon exposure to consecutive freeze-thaw cycles. an investigation was undertaken using several techniques to characterize fully the physicochemical changes l-asparaginase is undergoing during freeze-thaw cycling leading to the loss of its activity. a total protein assay suggested that the loss of s ... | 1997 | 9178179 |
| mutual control of the pecs/pecm couple, two proteins regulating virulence-factor synthesis in erwinia chrysanthemi. | the erwinia chrysanthemi pecs mutant displays constitutive production of virulence factors, such as pectinases or cellulases. complementation of the pecs mutation can be obtained in the presence of the pecs wild-type gene on a low-copy-number plasmid. moreover, the resulting plasmid decreases the expression of a pecs::uida chromosomal fusion, indicating the existence of an autoregulation mechanism. this negative autoregulation was confirmed and quantified by analysis of the pecs transcripts usin ... | 1997 | 9194707 |
| characterization of acquired resistance in lesion-mimic transgenic potato expressing bacterio-opsin. | the lesion-mimic mutants of certain plants display necrotic lesions resembling those of the hypersensitive response and activate local and systemic defense responses in the absence of pathogens. we have engineered a lesion-mimic phenotype in transgenic russet burbank potato plants through constitutive expression of a bacterio-opsin (bo) proton pump derived from halobacterium halobium. transgenic potato plants exhibiting a lesion-mimic phenotype had increased levels of salicylic acid and overexpr ... | 1997 | 9204568 |
| the rna molecule csrb binds to the global regulatory protein csra and antagonizes its activity in escherichia coli. | the rna-binding protein csra (carbon storage regulator) is a new kind of global regulator, which facilitates specific mrna decay. a recombinant csra protein containing a metal-binding affinity tag (csra-h6) was purified to homogeneity and authenticated by n-terminal sequencing, matrix-assisted laser desorption/ionization time of flight mass spectrometry, and other studies. this protein was entirely contained within a globular complex of approximately 18 csra-h6 subunits and a single approximatel ... | 1997 | 9211896 |
| specific interaction between outd, an erwinia chrysanthemi outer membrane protein of the general secretory pathway, and secreted proteins. | outd is an outer membrane component of the main terminal branch of the general secretory pathway (gsp) in erwinia chrysanthemi. we analyzed the interactions of outd with other components of the gsp (out proteins) and with secreted proteins (pelb, egz and pema). outd is stabilized by its interaction with another gsp component, outs. the 62 c-terminal amino acids of outd are necessary for this interaction. in vivo formation of outd multimers, up to tetramers, was proved after the dissociation in m ... | 1997 | 9214618 |
| identification of a bacterial pectin acetyl esterase in erwinia chrysanthemi 3937. | erwinia chrysanthemi causes soft-rot diseases of various plants by enzymatic degradation of the pectin in plant cell walls. the structural complexity of pectin requires the combined action of several pectinases for its efficient breakdown. three types of pectinases have so far been identified in e. chrysanthemi: two pectin methyl esterases (pema, pemb), a polygalacturonase (pehx), and eight pectate lyases (pela, pelb, pelc, peld, pele, pell, pelz, pelx). we report in this paper the analysis of a ... | 1997 | 9218776 |
| protein secretion by gram-negative bacterial abc exporters--a review. | one of the strategies used by gram-negative bacteria to secrete proteins across the two membranes which delimit the cells is sec-independent and dedicated to proteins lacking an n-terminal signal peptide. most of these proteins display a c-terminal secretion signal located in the last 60 amino acids (aa). using one erwinia chrysanthemi protease, prtg, secreted by such a pathway it was shown that the smallest c-terminal sequence allowing efficient secretion contains the last 29 aa of prtg and tha ... | 1997 | 9224868 |
| characterization of the pect control region from erwinia chrysanthemi 3937. | erwinia chrysanthemi synthesizes and secretes pectate lyases that attack components of the plant cell wall and, therefore, play a major role in the pathogenesis of soft rot disease. we isolated a new mutant (designated pec-1), by tn5 mutagenesis, that displays weak pectate lyase production and decreased motility and mucoidicity. maceration and pathogenicity tests done on different plant organs showed that the pec-1 strain displays a reduced virulence compared to that of the parental strain. the ... | 1997 | 9244282 |
| the pecm protein is necessary for the dna-binding capacity of the pecs repressor, one of the regulators of virulence-factor synthesis in erwinia chrysanthemi. | the pecs regulatory locus is responsible for the down-expression of many virulence genes in erwinia chrysanthemi. this locus consists of two genes, pecs and pecm, divergently transcribed. genetic evidence indicates that the pecm protein modulates the regulatory activity of pecs. purification and characterization of pecs, expressed either from e. coli, from the wild-type e. chrysanthemi strain or from a pecm mutant, showed that the pecs protein produced in these three genetic backgrounds displays ... | 1997 | 9311123 |
| avirulence gene d of pseudomonas syringae pv. tomato may have undergone horizontal gene transfer. | avirulence gene d (avrd) is carried on the b-plasmid of the plant pathogen pseudomonas syringae pv. tomato with plasmid-borne avrd homologs widely distributed among the pseudomonads. we now report sequences in the soft rot pathogen erwinia carotovora that cross-hybridize to avrd suggesting a conserved function beyond avirulence. alternatively, avrd may have been transferred horizontally among species: (i) dna linked to avrd shows evidence of class ii transpositions and contains a novel is3-relat ... | 1997 | 9326365 |
| pectate lyase peli of erwinia chrysanthemi 3937 belongs to a new family. | erwinia chrysanthemi 3937 secretes five major isoenzymes of pectate lyases encoded by the pel4, pelb, pelc, peld, and pele genes and a set of secondary pectate lyases, two of which, pell and pelz, have been already identified. we cloned the peli gene, encoding a ninth pectate lyase of e. chrysanthemi 3937. the peli reading frame is 1,035 bases long, corresponding to a protein of 344 amino acids including a typical amino-terminal signal sequence of 19 amino acids. the purified mature peli protein ... | 1997 | 9393696 |
| the rap and hor proteins of erwinia, serratia and yersinia: a novel subgroup in a growing superfamily of proteins regulating diverse physiological processes in bacterial pathogens. | the enteric bacterium serratia marcescens is an opportunistic human pathogen. the strain atcc39006 makes the red pigment, prodigiosin (pig), and the beta-lactam antibiotic carbapenem (car). mutants were isolated that were concomitantly defective for pig and car production. these mutants were found to have a mutation in the rap gene (regulation of antibiotic and pigment). sequence analysis of the rap gene revealed a predicted protein product showing strong homology to slya, originally thought to ... | 1997 | 9402023 |
| analysis of the carbapenem gene cluster of erwinia carotovora: definition of the antibiotic biosynthetic genes and evidence for a novel beta-lactam resistance mechanism. | members of two genera of gram-negative bacteria, serratia and erwinia, produce a beta-lactam antibiotic, 1-carbapen-2-em-3-carboxylic acid. we have reported previously the cloning and sequencing of the genes responsible for production of this carbapenem in erwinia carotovora. these genes are organized as an operon, cara--h, and are controlled by a luxr-type transcriptional activator, encoded by the linked carr gene. we report in this paper the genetic dissection of this putative operon to determ ... | 1997 | 9402024 |
| solution structure of the cellulose-binding domain of the endoglucanase z secreted by erwinia chrysanthemi. | two-dimensional proton nuclear magnetic resonance spectroscopy has been used to determine the three-dimensional structure of the 62 amino acid c-terminal cellulose-binding domain (cbd) of the endoglucanase z (cbdegz), secreted by erwinia chrysanthemi. an experimental data set comprising 958 interproton noe-derived restraints was used to calculate 23 structures. the calculated structures have an average root-mean-square deviation between cys4 and cys61 of 0.91 +/- 0.11 a for backbone atoms and 1. ... | 1997 | 9405041 |
| characterization of a periplasmic peptidyl-prolyl cis-trans isomerase in erwinia chrysanthemi. | the main determinant of the plant pathogen erwinia chrysanthemi virulence is the production of extracellular enzymes, mainly pectate lyases. adjacent to a pectate lyase encoding locus, we identified the gene rota supposed to encode a folding catalyst. overproduction of the protein and assay of activity using a synthetic substrate, confirmed that rota encodes a periplasmic peptidyl-prolyl cis-trans isomerase. rota disruption provokes no change in cell morphology, cell viability, growth rate or st ... | 1997 | 9418240 |
| antagonistic effect of crp and kdgr in the transcription control of the erwinia chrysanthemi pectinolysis genes. | the main virulence factors of the phytopathogenic bacteria erwinia chrysanthemi are pectinases that cleave pectin, a major constituent of the plant cell wall. the cyclic amp receptor protein (crp) was identified as the main activator of the pectinolysis genes. gel shift and dnase i footprinting experiments showed that the purified e. chrysanthemi crp protein binds specifically to the promoter regions of seven pectinolysis genes (pelb, pelc, peld, pele, ogl, kdui and kdgt) whose expression is pos ... | 1997 | 9426143 |
| elucidation of the structure of the core region and the complete structure of the r-type lipopolysaccharide of erwinia carotovora ferm p-7576. | an r-type lipopolysaccharide (lps) from erwinia carotovora strain ferm p-7576 was studied after strong alkaline degradation and mild acid hydrolysis. the resulting products were analyzed by fast-atom bombardment mass spectrometry, one- and two-dimensional 1h and 13c nmr spectroscopy, dephosphorylation and methylation analysis. the following structure was proposed for the core region of the lps: [formula in text] where hep is l-glycero-d-manno-heptose and kdo is 3-deoxy-d-manno-octulosonic acid. ... | 1997 | 9431990 |
| 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 |
| the interaction of shikimate kinase from erwinia chrystanthemi with substrates. | | 1997 | 9450055 |
| 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 |
| the rpos gene of erwinia carotovora: gene organization and functional expression in e. coli. | rpos homologues were identified in several erwinia species using escherichia coli rpos sequences as probes. the rpos gene from erwinia carotovora was cloned and the deduced amino acid sequence had 91% identity to e. coli rpos. the latter sigma factor regulates the stationary phase inducible hpii catalase activity of e. coli. in an e. coli rpos mutant, the e. carotovora rpos gene was also able to regulate synthesis of this catalase. the presence of a similar catalase in e. carotovora suggests tha ... | 1998 | 9503622 |
| external loops at the c terminus of erwinia chrysanthemi pectate lyase c are required for species-specific secretion through the out type ii pathway. | the type ii secretion system (main terminal branch of the general secretion pathway) is used by diverse gram-negative bacteria to secrete extracellular proteins. proteins secreted by this pathway are synthesized with an n-terminal signal peptide which is removed upon translocation across the inner membrane, but the signals which target the mature proteins for secretion across the outer membrane are unknown. the plant pathogens erwinia chrysanthemi and erwinia carotovora secrete several isozymes ... | 1998 | 9515910 |
| the leu-3 residue of serratia marcescens metalloprotease inhibitor is important in inhibitory activity and binding with serratia marcescens metalloprotease. | serratia marcescens metalloprotease inhibitor (smapi) is a proteinase inhibitor toward serratia marcescens metalloprotease (smp). in sequential deletion analysis of the n-terminal region of the smapi, smapis starting at ser-2 and leu-3 residues, respectively, had nearly a full inhibitory activity toward smp. however, smapi starting at ala-4 residue showed severely decreased inhibitory activity. furthermore, kinetic analysis demonstrated that smapi starting at the ala-4 residue had an inhibition ... | 1998 | 9521810 |
| the exut gene of erwinia chrysanthemi ec16: nucleotide sequence, expression, localization, and relevance of the gene product. | galacturonic acid (galua) is a major component of pectin and polygalacturonic acid in the plant cell wall. in the phytopathogen erwinia chrysanthemi, the uptake of molecules derived from degradation of these polymers is an important early step in the events preceding induction of pectinases, ultimately leading to plant tissue maceration. uptake systems for galua and dimers of galua have been described and shown to be inducible in e. chrysanthemi. the galua uptake gene (exut) was cloned and seque ... | 1998 | 9530868 |
| 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 |
| the three-dimensional structure of shikimate kinase. | the three-dimensional structure of shikimate kinase from erwinia chrysanthemi has been determined by multiple isomorphous replacement. two models are presented: a high resolution 1.9 a model and a 2.6 a model which contains bound mg-adp. the enzyme is an alpha/beta protein consisting of a central sheet of five parallel beta-strands flanked by alpha-helices with overall topology similar to adenylate kinase. evidence is presented that shikimate kinase undergoes major conformational changes on liga ... | 1998 | 9600856 |
| biochemical characterization of the pectate lyase pelz of erwinia chrysanthemi 3937. | to degrade the plant pectin, the phytopathogenic bacterium erwinia chrysanthemi produces a set of at least seven endo-pectate lyases (pels). five major (pela, pelb, pelc, peld and pele) and two minor isoenzymes (pell and pelz) have been identified. pelz is an extracellular enzyme secreted by the out system. according to its amino acid sequence, the pelz protein belongs to a new family. the pelz protein was overproduced in e. coli and purified to compare its enzymatic properties to that of the ot ... | 1998 | 9602123 |
| the hrpc and hrpn operons of erwinia chrysanthemi ec16 are flanked by plca and homologs of hemolysin/adhesin genes and accompanying activator/transporter genes. | the hrpc operon of erwinia chrysanthemi ec16 encodes five genes conserved in erwinia amylovora and pseudomonas syringae. mutagenesis indicated that hrcc is required for elicitation of the hypersensitive reaction in tobacco leaves. the unexpected presence of plca and homologs of hemolysin/activator genes in the regions flanking the hrcc and hrpn operons is reported. | 1998 | 9612954 |