Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Pectobacterium”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed2005

Sensitive and specific detection of Xanthomonas axonopodis pv. citri by PCR using pathovar specific primers based on hrpW gene sequences.

A sensitive and specific assay was developed to detect citrus bacterial canker caused by Xanthomonas axonopodis pv. citri, in leaves and fruits of citrus. Primers XACF and XACR from hrpW homologous to pectate lyase, modifying the structure of pectin in plants, were used to amplify a 561 bp DNA fragment. PCR technique was applied to detect the pathogen in naturally or artificially infected leaves of citrus. The PCR product was only produced from X. axonopodis pv. citri among 26 isolates of Xanthomonas strains, Escherichia coli (O157:H7), Pectobacterium carotovorum subsp. carotovorum, and other reference microbes.

Citrus↗
PubMed1977

Bacterial stalk rot of Maize, its symptoms and host-range.

Stalk rot of maize, caused by Erwinia carotovora f. sp. zeae Sabet (re-designated as Pectobacterium chrysanthemi pathovar. zeae by KELMAN 1974) showed first premature withering and drying up of the uppermost leaves which was soon followed by the lower leaves. The rot either extended from the base upwards (basal rot) or from the top downwards (top rot). In the case of basal rot, the leaves become yellow and the infected tissue becomes brown, soft, and water soaked. Internally, the stalk turns into a soft mass of disintegrated tissue. At this stage the plants usually topple over. A foul odour, accompanied with the presence of dipterous larvae on and in decaying tissues, are the characteristic symptoms of this disease. With the advance of the disease the stalk finally dries up into a conglomeration of dry and shredded or disjointed fibrous tissue. The top rot begins with wilting and drying up ot the tips of middle leaves of the whorl. A decay that continues rapidly spreads downwards throughout the stalk and the affected plants soon droop. The host range studies were suggestive of the fact that the maize pathogen, apart from causing the disease on maize, could produce soft rot in potato, carrot, onion, sugarbeet, sweet potato, papaya, cabbage, and many other plants and could also infect Sorghum vulgare, Pennisetum typhoidium, tobacco, and tomato.

Ecology↗
PubMed1998

Phylogenetic position of phytopathogens within the Enterobacteriaceae.

The almost complete 16S rDNA sequences of twenty nine plant-associated strains, representing species of the genera Erwinia, Pantoea and Enterobacter were determined and compared with those of other members of the Enterobacteriaceae. The species of the genus Erwinia may be divided into three phylogenetic groups. Cluster I represents the true erwinias and comprises E. amylovora, E. mallotivora, E. persicinus, E. psidii, E. rhapontici and E. tracheiphila. We propose to unite the species of cluster II, E. carotovora subsp. atroseptica, E. carotovora subsp. betavasculorum, E. carotovora subsp. carotovora, E. carotovora subsp. odorifera, E. carotovora subsp. wasabiae, E. cacticida, E. chrysanthemi and E. cypripedii in the genus Pectobacterium respectively as P. carotovorum subsp. atrosepticum comb. nov., P. carotovorum subsp. betavasculorum comb. nov., P. carotovorum subsp. carotovorum comb. nov., P. carotovorum subsp. odoriferum comb. nov., P. carotovorum subsp. wasabiae comb. nov., P. cacticidum comb. nov., P. chrysanthemi and P. cypripedii. The species E. alni, E. nigrifluens, E. paradisiaca, E. quercina, E. rubrifaciens and E. salicis, comprising cluster III, are being classified into a new genus Brenneria gen. nov. respectively as B. alni comb. nov., B. nigrifluens comb. nov., B. paradisiaca comb. nov., B. quercina comb. nov., B. rubrifaciens comb. nov. and B. salicis comb. nov. The species of the genus Pantoea, included in this study, form a monophyletic unit (cluster IV), closely related with Erwinia, whereas the three phytopathogenic species of the genus Enterobacter are scattered among the genera Citrobacter and Klebsiella.

Bacterial Typing Techniques↗
PubMed2005

Isolation and antifungal activity of 4-phenyl-3-butenoic acid from Streptomyces koyangensis strain VK-A60.

An antifungal compound was isolated from the culture broth of Streptomyces koyangensis strain VK-A60 using various chromatographic procedures. On the basis of the high-resolution EI-mass and 1H and 13C NMR data, the compound was identified as 4-phenyl-3-butenoic acid. Colletotrichum orbiculare, Magnaporthe grisea, and Pythium ultimum were most sensitive to 4-phenyl-3-butenoic acid. Strong inhibitory effects of 4-phenyl-3-butenoic acid also were found against Pectobacterium carotovorum subsp. carotovorum and Ralstonia solanacearum. 4-Phenyl-3-butenoic acid effectively suppressed the development of M. grisea on rice leaves at the concentration of more than 10 microg/mL, and the protective activity was in general similar to that of the commercial fungicide tricyclazole. Treatment with 100 microg/mL of 4-phenyl-3-butenoic acid also effectively inhibited the anthracnose development on cucumber plants, although its in vivo efficacy was somewhat less effective than that of the commercial fungicide chlorothalonil.

Culture Media, Conditioned↗
PubMed1999

Reclassification of non-pigmented Erwinia herbicola strains from trees as Erwinia billingiae sp. nov.

Twenty-two Erwinia-like strains, isolated from trees since the late fifties and belonging to a distinct phenotypic group with resemblance to Pantoea agglomerans, were further characterized by conventional biochemical tests, the BIOLOG metabolic fingerprinting system and fatty acid analysis. Their phylogenetic positions were determined by comparing the 16S rRNA gene sequence of a representative strain to available sequences of Erwinia, Pantoea, Pectobacterium and Brenneria species. The strains were shown to belong to the genus Erwinia, with Erwinia rhapontici and Erwinia persicina as the closest phylogenetic relatives. The name Erwinia billingiae sp. nov. is proposed (type strain LMG 2613T) and a description of the species is given.

Bacterial Typing Techniques↗
PubMed1999

The phylogenetic position of Serratia, Buttiauxella and some other genera of the family Enterobacteriaceae.

The phylogenetic relationships of the type strains of 38 species from 15 genera of the family Enterobacteriaceae were investigated by comparative 16S rDNA analysis. Several sequences of strains from the genera Citrobacter, Erwinia, Pantoea, Proteus, Rahnella and Serratia, analysed in this study, have been analysed previously. However, as the sequences of this study differ slightly from the published ones, they were included in the analysis. Of the 23 enterobacterial genera included in an overview dendrogram of relatedness, members of the genera Xenorhabdus, Photorhabdus, Proteus and Plesiomonas were used as a root. The other genera formed two groups which could be separated, although not exclusively, by signature nucleotides at positions 590-649 and 600-638. Group A contains species of Brenneria, Buttiauxella, Citrobacter, Escherichia, Erwinia, Klebsiella, Pantoea, Pectobacterium and Salmonella. All seven type strains of Buttiauxella share 16S rDNA similarities greater than 99%. Group B embraces two phylogenetically separate Serratia clusters, a lineage containing Yersinia species, Rahnella aquatica, Ewingella americana, and also the highly related pair Hafnia alvei and Obesumbacterium proteus.

DNA, Ribosomal↗
PubMed2001

Samsonia erythrinae gen. nov., sp. nov., isolated from bark necrotic lesions of Erythrina sp., and discrimination of plant-pathogenic Enterobacteriaceae by phenotypic features.

Bacterial strains isolated from diseased erythrina (Erythrina sp.) trees in Martinique (French West Indies) were studied using phenotypic tests, 16S rDNA sequence analysis and DNA-DNA hybridization. Numerical analysis of phenotypic characteristics showed that these strains formed an homogeneous phenon among plant-pathogenic Enterobacteriaceae, and gave useful and updated information for the identification of these bacteria. Results of DNA-DNA hybridization indicated that strains from erythrina belonged to a discrete genomospecies (89-100% hybridization) and had low levels of DNA relatedness (2-33% hybridization) with reference strains of phytopathogenic Erwinia, Brenneria, Pectobacterium, Pantoea and Enterobacter species. 16S rDNA sequence analysis using three different methods revealed that the position of strain CFBP 5236T isolated from erythrina was variable in the different trees, so that strains from erythrina could not be assigned to any recognized genus. It is proposed that these strains are included in a new genus, Samsonia. The name Samsonia erythrinae is proposed for the new species. The G+C content of the DNA of the type strain, CFBP 5236T (= ICMP 13937T), is 57.0 mol%.

Base Composition↗
PubMed2003

Novel bacteria degrading N-acylhomoserine lactones and their use as quenchers of quorum-sensing-regulated functions of plant-pathogenic bacteria.

Bacteria degrading the quorum-sensing (QS) signal molecule N-hexanoylhomoserine lactone were isolated from a tobacco rhizosphere. Twenty-five isolates degrading this homoserine lactone fell into six groups according to their genomic REP-PCR and rrs PCR-RFLP profiles. Representative strains from each group were identified as members of the genera Pseudomonas, Comamonas, Variovorax and Rhodococcus: all these isolates degraded N-acylhomoserine lactones other than the hexanoic acid derivative, albeit with different specificity and kinetics. One of these isolates, Rhodococcus erythropolis strain W2, was used to quench QS-regulated functions of other microbes. In vitro, W2 strongly interfered with violacein production by Chromobacterium violaceum, and transfer of pathogenicity in Agrobacterium tumefaciens. In planta, R. erythropolis W2 markedly reduced the pathogenicity of Pectobacterium carotovorum subsp. carotovorum in potato tubers. These series of results reveal the diversity of the QS-interfering bacteria in the rhizosphere and demonstrate the validity of targeting QS signal molecules to control pathogens with natural bacterial isolates.

4-Butyrolactone↗
PubMed1998

PCR-Based detection of the causal agent of watermark disease in willows (Salix spp.)

The watermark disease, caused by Brenneria salicis (formerly Erwinia salicis), is of significant concern wherever tree-forming willows are grown or occur naturally. The movement of infected, asymptomatic cuttings is a major cause of pathogen dispersal. A reliable and sensitive diagnostic procedure is necessary for the safe movement of willow planting material. We derived primers from the nucleotide sequence of the 16S rRNA gene of B. salicis for the development of a PCR to detect this pathogen. One set of primers, Es1a-Es4b, directed the amplification of a 553-bp fragment from B. salicis genomic DNA as well as B. salicis cells. PCR products were not observed when genomic DNA was tested for 27 strains of other, related plant-associated bacteria. Genomic fingerprinting by amplification fragment length polymorphism of B. salicis strains, originating from four different countries, and related Brenneria, Pectobacterium, and Erwinia strains revealed a very high similarity among the B. salicis genomes, indicating that the spread of the pathogen is mainly due to the transportation of infected cuttings. The PCR had to be preceded by a DNA extraction in order to detect the pathogen in the vascular fluid of willows. The minimum number of cells that could be detected from vascular fluid was 20 CFU/ml. The PCR assays proved to be very sensitive and reliable in detecting B. salicis in willow plant material.

Journal Article↗
PubMed2005

Involvement of bacterial quorum-sensing signals in spoilage of bean sprouts.

Bacterial communication signals, acylated homoserine lactones (AHLs), were extracted from samples of commercial bean sprouts undergoing soft-rot spoilage. Bean sprouts produced in the laboratory did not undergo soft-rot spoilage and did not contain AHLs or AHL-producing bacteria, although the bacterial population reached levels similar to those in the commercial sprouts, 10(8) to 10(9) CFU/g. AHL-producing bacteria (Enterobacteriaceae and pseudomonads) were isolated from commercial sprouts, and strains that were both proteolytic and pectinolytic were capable of causing soft-rot spoilage in bean sprouts. Thin-layer chromatography and liquid chromatography-high-resolution mass spectrometry revealed the presence of N-3-oxo-hexanoyl-l-homoserine lactone in spoiled bean sprouts and in extracts from pure cultures of bacteria. During normal spoilage, the pH of the sprouts increased due to proteolytic activity, and the higher pH probably facilitated the activity of pectate lyase. The AHL synthetase gene (I gene) from a spoilage Pectobacterium was cloned, sequenced, and inactivated in the parent strain. The predicted amino acid sequence showed 97% homology to HslI and CarI in Erwinia carotovora. Spoilage of laboratory bean sprouts inoculated with the AHL-negative mutant was delayed compared to sprouts inoculated with the wild type, and the AHL-negative mutant did not cause the pH to rise. Compared to the wild-type strain, the AHL-negative mutant had significantly reduced protease and pectinase activities and was negative in an iron chelation (siderophore) assay. This is the first study demonstrating AHL regulation of iron chelation in Enterobacteriaceae. The present study clearly demonstrates that the bacterial spoilage of some food products is influenced by quorum-sensing-regulated phenotypes, and understanding these processes may be useful in the development of novel food preservation additives that specifically block the quorum-sensing systems.

4-Butyrolactone↗
PubMed2006

The phytopathogen Dickeya dadantii (Erwinia chrysanthemi 3937) is a pathogen of the pea aphid.

Dickeya dadantii (Erwinia chrysanthemi) is a phytopathogenic bacterium causing soft rot diseases on many crops. The sequencing of its genome identified four genes encoding homologues of the Cyt family of insecticidal toxins from Bacillus thuringiensis, which are not present in the close relative Pectobacterium carotovorum subsp. atrosepticum. The pathogenicity of D. dadantii was tested on the pea aphid Acyrthosiphon pisum, and the bacterium was shown to be highly virulent for this insect, either by septic injury or by oral infection. The lethal inoculum dose was calculated to be as low as 10 ingested bacterial cells. A D. dadantii mutant with the four cytotoxin genes deleted showed a reduced per os virulence for A. pisum, highlighting the potential role of at least one of these genes in pathogenicity. Since only one bacterial pathogen of aphids has been previously described (Erwinia aphidicola), other species from the same bacterial group were tested. The pathogenic trait for aphids was shown to be widespread, albeit variable, within the phytopathogens, with no link to phylogenetic positioning in the Enterobacteriaceae. Previously characterized gut symbionts from thrips (Erwinia/Pantoea group) were also highly pathogenic to the aphid, whereas the potent entomopathogen Photorhabdus luminescens was not. D. dadantii is not a generalist insect pathogen, since it has low pathogenicity for three other insect species (Drosophila melanogaster, Sitophilus oryzae, and Spodoptera littoralis). D. dadantii was one of the most virulent aphid pathogens in our screening, and it was active on most aphid instars, except for the first one, probably due to anatomical filtering. The observed difference in virulence toward apterous and winged aphids may have an ecological impact, and this deserves specific attention in future research.

Animals↗
PubMed2004

The global regulator genes from biocontrol strain Serratia plymuthica IC1270: cloning, sequencing, and functional studies.

The biocontrol activity of various fluorescent pseudomonads towards plant-pathogenic fungi is dependent upon the GacA/GacS-type two-component system of global regulators and the RpoS transcription sigma factor. In particular, these components are required for the production of antifungal antibiotics and exoenzymes. To investigate the effects of these global regulators on the expression of biocontrol factors by plant-associated bacteria other than Pseudomonas spp., gacA/gacS and rpoS homologues were cloned from biocontrol strain IC1270 of Serratia plymuthica, which produces a set of antifungal compounds, including chitinolytic enzymes and the antibiotic pyrrolnitrin. The nucleotide and deduced protein sequence alignments of the cloned gacA/gacS-like genes-tentatively designated grrA (global response regulation activator) and grrS (global response regulation sensor) and of the cloned rpoS gene revealed 64 to 93% identity with matching genes and proteins of the enteric bacteria Escherichia coli, Pectobacterium carotovora subsp. carotovora, and Serratia marcescens. grrA, grrS, and rpoS gene replacement mutants of strain IC1270 were deficient in the production of pyrrolnitrin, an exoprotease, and N-acylhomoserine lactone quorum-sensing signal molecules. However, neither mutant appeared to differ from the parental strain in the production of siderophores, and only grrA and grrS mutants were deficient in the production of a 58-kDa endochitinase, representing the involvement of other sigma factors in the regulation of strain IC1270's chitinolytic activity. Compared to the parental strain, the grrA, grrS, and rpoS mutants were markedly less capable of suppressing Rhizoctonia solani and Pythium aphanidermatum under greenhouse conditions, indicating the dependence of strain IC1270's biocontrol property on the GrrA/GrrS and RpoS global regulators.

Antifungal Agents↗
PubMed2005

Identification of Erwinia amylovora genes induced during infection of immature pear tissue.

The enterobacterium Erwinia amylovora is a devastating plant pathogen causing necrotrophic fire blight disease of apple, pear, and other rosaceous plants. In this study, we used a modified in vivo expression technology system to identify E. amylovora genes that are activated during infection of immature pear tissue, a process that requires the major pathogenicity factors of this organism. We identified 394 unique pear fruit-induced (pfi) genes on the basis of sequence similarity to known genes and separated them into nine putative function groups including host-microbe interactions (3.8%), stress response (5.3%), regulation (11.9%), cell surface (8.9%), transport (13.5%), mobile elements (1.0%), metabolism (20.3%), nutrient acquisition and synthesis (15.5%), and unknown or hypothetical proteins (19.8%). Known virulence genes, including hrp/hrc components of the type III secretion system, the major effector gene dspE, type II secretion, levansucrase (lsc), and regulators of levansucrase and amylovoran biosynthesis, were upregulated during pear tissue infection. Known virulence factors previously identified in E. (Pectobacterium) carotovora and Pseudomonas syringae were identified for the first time in E. amylovora and included HecA hemagglutinin family adhesion, Peh polygalacturonase, new effector HopPtoC(EA), and membrane-bound lytic murein transglycosylase MltE(EA). An insertional mutation within hopPtoC(EA) did not result in reduced virulence; however, an mltE(EA) knockout mutant was reduced in virulence and growth in immature pears. This study suggests that E. amylovora utilizes a variety of strategies during plant infection and to overcome the stressful and poor nutritional environment of its plant hosts.

Erwinia amylovora↗
PubMed2006

The survival of pathogens in soil treated with wastewater sludge and in potatoes grown in such soil.

The prevalence of pathogens on potatoes (Solanum tuberosum) grown in soil amended with a pathogen rich wastewater sludge was investigated. Bacteria of the family Enterobacteriaceae are important pathogens causing intestinal and systemic illness of humans and other animals. Type B sludge was used. Sludges investigated are the high metal and the low metal sludges. Microorganisms in the sludge-amended soil were using culture-based technique. Salmonella and E. coli were observed in tested soil samples. No microorganisms were isolated from control samples taken throughout the process of the experiment. At harvest time, some of the potato samples from LMS soil were contaminated. These potatoes were subjected to further investigation using molecular techniques (polymerase chain reaction) with fD1 and rP2 as primers. Organisms identified from the sequenced potato peel samples with the BLAST search tool included Enterobacter agglomerans (Pantoea agglomerans), several Buttiauxella spp., Pectobacterium spp., Erwinia spp. and a few Pantoea spp. Other than the E. agglomerans, which is commonly found in the gut and upper respiratory tract of humans and in the environment, all the other species identified were found to be mainly either plant or soil pathogens. The E. agglomerans are not primary pathogens but secondary opportunistic pathogens particularly in immunocompromised individuals. These results suggest that growing high risk crops using wastewater sludge contaminated soil may lead to limited infestation of produce with primary pathogens. It appears that the use of HMS due to early pathogen die-off provides less risk of infection than the LMS. However, proper treatment of wastewater sludge to reduce pathogen load is essential prior to its use as soil conditioner.

Escherichia coli↗
PubMed1982

[Antibiotic sensitivity of opportunistic bacteria isolated from patients].

Sensitivity of 147 Enterobacteria strains isolated from feces of various patients was determined with the method of serial dilutions on solid nutrient media. 8 antibiotics were tested. By genera (species) the microorganisms were arranged in the following order: E. coli (65 strains), Citrobacter (33 strains), E. cloacae (15 strains), Serratia liquefaciens (9 strains), Hafnia (6 strains), Klebsiella (4 strains), Pectobacterium (3 strains), non-identified organisms (13 strains). The majority of the strains were resistant to levomycetin (chloramphenicol), morphocycline, tetracycline and tetraolean and at the same time sensitive to streptomycin, neomycin, monomycin and kanamycin. 18 combinations of resistance were found. Repeated examinations of the specimens from the same patient revealed changes in the species composition of the cultures and subsequently in the antibiotic sensitivity spectrum.

Anti-Bacterial Agents↗
PubMed1992

Allergic reactions to Erwinia asparaginase in children with acute lymphoblastic leukemia who had previous allergic reactions to Escherichia coli asparaginase.

BACKGROUND: Escherichia coli asparaginase is an active antileukemia agent in the treatment of childhood acute lymphoblastic leukemia. Allergic reactions occurred in 31 of 125 patients (24.8%) treated with weekly high-dose (25,000 IU/m2) intramuscular E. coli asparaginase and necessitated discontinuation of the drug. METHODS: The authors evaluated the toxic effects of Erwinia asparaginase in the 31 children who had allergic reactions to the E. coli preparation. RESULTS: Subsequent allergic reactions to Erwinia asparaginase occurred in 7 of the 31 children (22.6%). In contrast to previous reports with intravenous administration, most allergic reactions to both asparaginase preparations were characterized by mild urticaria that responded to use of diphenhydramine; none of the reactions was life-threatening. CONCLUSIONS: In summary, the authors found Erwinia asparaginase to be an acceptable substitute for E. coli asparaginase for most children who had allergic reactions. Through the use of both E. coli and Erwinia asparaginase, 94% of children could receive their intended asparaginase.

Adolescent↗
PubMed2006

Restraining Erwinia virulence by expression of N-acyl homoserine lactonase gene pro3A-aiiA in Bacillus thuringiensis subsp leesis.

To widen the biological control function of a genetically modified Bacillus thuringiensis subsp leesis strain BMB-005, an acyl homoserine lactonase (AHL lactonase) gene aiiA transcribed by the promoter of insecticidal crystal protein coding gene cry3A, was transformed into strain BMB-005. The amount of AHL lactonase protein produced by transformant BMB821A was 2.4-fold more than that produced by BMB-005. AHL-degradation assay showed that transformant BMB821A could degrade more AHLs molecules than the original strain BMB-005. The result of Erwinia carotovora pathogenicity test showed that the parental strain BMB-005 had no restraint of Erwinia infection, but the transformants exhibited strong restraint of E. carotovora infection on potato slices and cactus stems. Insecticidal bioassay against lepidopteran Spodoptera exigua showed that both strain BMB-005 and transformant BMB821A were toxic to S. exigua. The toxicity of transformant BMB821A (LC(50) was 3.8) was a little attenuated comparing with the toxicity of the original strain BMB-005 (LC(50) was 2.9). The B. thuringiensis strain BMB-005 has high toxicity against Helicoverpa armigera, Plutella xylostella, and S. exigua. This work provided new strategy for developing genetically engineered multi-functional B. thuringiensis strain that possesses insecticidal activity together with restraint of bacterial pathogenicity.

Animals↗
PubMed1993

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 functionally related to the luxI gene product of Vibrio fischeri. Functional similarity of expI and luxI has been demonstrated by reciprocal genetic complementation experiments. LuxI controls bioluminescence in V.fischeri in a growth phase-dependent manner by directing the synthesis of the diffusible autoinducer, N-(3-oxohexanoyl) homoserine lactone. E.c. subsp. carotovora expI+ strains or Escherichia coli harboring the cloned expI gene excrete a small diffusible signal molecule that complements the expI mutation of Erwinia as well as a luxI mutation of V.fischeri. This extracellular complementation can also be achieved by E.coli harboring the luxI gene from V.fischeri or by adding the synthetic V.fischeri autoinducer. Both the production of the plant tissue-macerating exoenzymes and the ability of the bacteria to propagate in planta are restored in expI mutants by autoinducer addition. These data suggest that the same signal molecule is employed in control of such diverse processes as virulence in a plant pathogen and bioluminescence in a marine bacterium, and may represent a general mechanism by which bacteria modulate gene expression in response to changing environmental conditions.

Amino Acid Sequence↗