| mass spectrometric analysis reveals remnants of host-pathogen molecular interactions at the starch granule surface in wheat endosperm. | the starch granules of wheat seed are solar energy-driven deposits of fixed carbon and, as such, present themselves as targets of pathogen attack. the seed's array of antimicrobial proteins, peptides, and small molecules comprises a molecular defense against penetrating pathogens. in turn, pathogens exhibit an arsenal of enzymes to facilitate the degradation of the host's endosperm. in this context, the starch granule surface is a relatively unexplored domain in which unique molecular barriers m ... | 2010 | 20701481 |
| looking inside the box: using raman microspectroscopy to deconstruct microbial biomass stoichiometry one cell at a time. | stoichiometry of microbial biomass is a key determinant of nutrient recycling in a wide variety of ecosystems. however, little is known about the underlying causes of variance in microbial biomass stoichiometry. this is primarily because of technological constraints limiting the analysis of macromolecular composition to large quantities of microbial biomass. here, we use raman microspectroscopy (ms), to analyze the macromolecular composition of single cells of two species of bacteria grown on mi ... | 2011 | 20703314 |
| regulation of motility in erwinia carotovora subsp. carotovora: quorum-sensing signal controls flhdc, the global regulator of flagellar and exoprotein genes, by modulating the production of rsma, an rna-binding protein. | erwinia carotovora subsp. carotovora causes soft-rotting (tissue-macerating) disease in many plants and plant organs. although pectinases are the primary determinants of virulence, several ancillary factors that augment bacterial virulence have also been identified. one such factor is bacterial motility. flagellum formation and bacterial movement are regulated in many enterobacteria, including e. carotovora subsp. carotovora, by flhdc, the master regulator of flagellar genes and flia, a flagellu ... | 2010 | 20831410 |
| regulatory mechanisms of exoribonuclease pnpase and regulatory small rna on t3ss of dickeya dadantii. | the type iii secretion system (t3ss) is an essential virulence factor for many bacterial pathogens. polynucleotide phosphorylase (pnpase) is one of the major exoribonucleases in bacteria and plays important roles in mrna degradation, trna processing, and small rna (srna) turnover. in this study, we showed that pnpase downregulates the transcription of t3ss structural and effector genes of the phytopathogenic bacterium dickeya dadantii. this negative regulation of t3ss by pnpase occurs by repress ... | 2010 | 20831411 |
| purification and characterization of glutaminase-free l-asparaginase from pectobacterium carotovorum mtcc 1428. | an intracellular glutaminase-free l-asparaginase from pectobacterium carotovorum mtcc 1428 was isolated to apparent homogeneity. the homotetramer enzyme has a molecular mass of 144.4 kda (maldi-tof ms) and an isoelectric point of approximately 8.4. the enzyme is very specific for its natural substrate, l-asparagine. the activity of l-asparaginase is activated by mono cations and various effectors including na+, k+, l-cystine, l-histidine, glutathione and 2-mercaptoethanol whereas it is moderatel ... | 2011 | 20832300 |
| reverse engineering gene regulatory networks related to quorum sensing in the plant pathogen pectobacterium atrosepticum. | the objective of the project reported in the present chapter was the reverse engineering of gene regulatory networks related to quorum sensing in the plant pathogen pectobacterium atrosepticum from micorarray gene expression profiles, obtained from the wild-type and eight knockout strains. to this end, we have applied various recent methods from multivariate statistics and machine learning: graphical gaussian models, sparse bayesian regression, lasso (least absolute shrinkage and selection opera ... | 2010 | 20835805 |
| a test of taxonomic and biogeographic predictivity: resistance to soft rot in wild relatives of cultivated potato. | the concept that traits should be associated with related organisms and that nearby populations of the same species are likely to be more similar to each other than to populations spread far apart has long been accepted. consequently, taxonomic relationships and biogeographical data are commonly believed to have the power to predict the distribution of disease resistance genes among plant species. in this study, we test claims of such predictivity in a group of widely distributed wild potato spe ... | 2011 | 20839961 |
| characterization of a new bacteriocin, carocin d, from pectobacterium carotovorum subsp. carotovorum pcc21. | two different bacteriocins, carotovoricin and carocin s1, had been found in pectobacterium carotovorum subsp. carotovorum, which causes soft-rot disease in diverse plants. previously, we reported that the particular strain pcc21, producing only one high-molecular-weight bacteriocin, carried a new antibacterial activity against the indicator strain pcc3. here, we report that this new antibacterial activity is due to a new bacteriocin produced by strain pcc21 and named carocin d. carocin d is enco ... | 2010 | 20870796 |
| discovery of a quorum sensing modulator pharmacophore by 3d small-molecule microarray screening. | the screening of large arrays of drug-like small-molecules was traditionally a time consuming and resource intensive task. new methodology developed within our laboratories provides an attractive low cost, 3d microarray-assisted screening platform that could be used to rapidly assay thousands of compounds. as a proof-of-principle the platform was exploited to screen a number of quorum sensing analogs. quorum sensing is used by bacterium to initiate and spread infection; in this context its modul ... | 2010 | 20886127 |
| downward vascular translocation of a green fluorescent protein-tagged strain of dickeya sp. (biovar 3) from stem and leaf inoculation sites on potato. | translocation of a green fluorescent protein (gfp)-tagged dickeya sp. from stems or from leaves to underground parts of potato plants was studied in greenhouse experiments. thirty days after stem inoculation, 90% of plants expressed symptoms at the stem base and 95% of plants showed browning of internal stem tissue. the gfp-tagged dickeya sp. was detected by dilution plating in extracts of the stem interiors (100%), stem bases (90%), roots (80%), stolons (55%), and progeny tubers (24%). in roots ... | 2010 | 20932162 |
| occurrence of pectobacterium carotovorum strains isolated from potato soft rot in morocco. | pectobacterium carotovorum subsp. carotovorum, pectobacterium astrosepticum and pectobacterium chrysanthemi are the soft rot tuber of potatoes pathogens (solanum tuberosum). the aim of this study was to determine the occurrence of these pathogens in moroccan regions producing potatoes. fifty three isolates of pectobacterium were isolated on medium crystal violet pectate. the comparison of their bacteriological characteristics with standard strains allowed us to conclude that all the isolates bel ... | 2010 | 20937219 |
| aiia-mediated quorum quenching does not affect virulence or toxoflavin expression in burkholderia glumae sl2376. | the primary objective of this study was to determine the effects of quorum quenching in the pathogenicity and toxoflavin production of burkholderia glumae causing bacterial rice grain rot. | 2010 | 21039666 |
| specificity of monoclonal antibodies to strains of dickeya sp. that cause bacterial heart rot of pineapple. | during a severe outbreak of bacterial heart rot that occurred in pineapple plantations on oahu, hawaii, in 2003 and years following, 43 bacterial strains were isolated from diseased plants or irrigation water and identified as erwinia chrysanthemi (now dickeya sp.) by phenotypic, molecular, and pathogenicity assays. rep-pcr fingerprint patterns grouped strains from pineapple plants and irrigation water into five genotypes (a-e) that differed from representatives of other dickeya species, pectoba ... | 2010 | 21050038 |
| simple method of differentiating erwinia carotovora variety 'atroseptica' from e. carotovora and e. carotovora variety 'aroideae'. | | 1966 | 21105516 |
| [polypeptide composition and killer specificity as indices of multiplicity of carotovoricins]. | a method of separation and purification of macromolecular bacteriocins of phytopathogenic bacterium erwinia carotovora is proposed. it is shown on the basis of polypeptide composition of the particles and their killer specificity, that e. carotovora esp86 is a complex defective-polylysogenic system which includes no less than three different types of biologically active tails of incomplete temperate bacteriophages. | 2010 | 21117296 |
| quorum sensing in bacterial species that use degenerate autoinducers can be tuned by using structurally identical non-native ligands. | many bacteria use quorum sensing (qs) to regulate cell-density dependent phenotypes that play critical roles in the maintenance of their associations with eukaryotic hosts. in gram-negative bacteria, qs is primarily controlled by n-acylated l-homoserine lactone (ahl) signals and their cognate luxr-type receptors. ahl-luxr-type receptor binding regulates the expression of target genes necessary for qs phenotypes. we recently identified a series of non-native ahls capable of intercepting ahl-luxr ... | 2011 | 21154995 |
| identification of two feruloyl esterases in dickeya dadantii 3937 and induction of the major feruloyl esterase and of pectate lyases by ferulic acid. | the plant-pathogenic bacterium dickeya dadantii (formerly erwinia chrysanthemi) produces a large array of plant cell wall-degrading enzymes. using an in situ detection test, we showed that it produces two feruloyl esterases, faed and faet. these enzymes cleave the ester link between ferulate and the pectic or xylan chains. faed and faet belong to the carbohydrate esterase family ce10, and they are the first two feruloyl esterases to be identified in this family. cleavage of synthetic substrates ... | 2010 | 21169494 |
| pectin methylesterase is induced in arabidopsis upon infection and is necessary for a successful colonization by necrotrophic pathogens. | the ability of bacterial or fungal necrotrophs to produce enzymes capable of degrading pectin is often related to a successful initiation of the infective process. pectin is synthesized in a highly methylesterified form and is subsequently de-esterified in muro by pectin methylesterase. de-esterification makes pectin more susceptible to the degradation by pectic enzymes such as endopolygalacturonases (endopg) and pectate lyases secreted by necrotrophic pathogens during the first stages of infect ... | 2011 | 21171891 |
| drosophila egfr pathway coordinates stem cell proliferation and gut remodeling following infection. | gut homeostasis is central to whole organism health, and its disruption is associated with a broad range of pathologies. following damage, complex physiological events are required in the gut to maintain proper homeostasis. previously, we demonstrated that ingestion of a nonlethal pathogen, erwinia carotovora carotovora 15, induces a massive increase in stem cell proliferation in the gut of drosophila. however, the precise cellular events that occur following infection have not been quantitative ... | 2010 | 21176204 |
| assessment of root-associated paenibacillus polymyxa groups on growth promotion and induced systemic resistance in pepper. | twenty-nine p. polymyxa strains isolated from rhizospheres of various crops were clustered into five genotypic groups on the basis of box-pcr analysis. the characteristics of several plant growth-promoting factors among the isolates revealed the distinct attributes in each allocated group. under gnotobiotic conditions, inoculation of pepper roots with p. polymyxa isolates significantly increased the biomass in 17 of total 29 treated plants with untreated plants. experiments on induced systemic r ... | 2010 | 21193814 |
| natural-light labeling of tomatoes does not facilitate growth or penetration of salmonella into the fruit. | the survival-growth capacity of salmonella populations on tomato epidermis labeled by a natural-light labeling system was investigated after persistent fears of such marks serving as possible entryways for the pathogenic organisms, alone and in the presence of pectobacterium carotovorum subsp. carotovorum, a soft-rot organism. different treatments involving natural-light labeling, fruit waxing, and a five-strain cocktail of salmonella were applied to mature green tomato surfaces in different seq ... | 2010 | 21219748 |
| a processed noncoding rna regulates an altruistic bacterial antiviral system. | the ≥ 10³⁰ bacteriophages on earth relentlessly drive adaptive coevolution, forcing the generation of protective mechanisms in their bacterial hosts. one such bacterial phage-resistance system, toxin, consists of a protein toxin (toxn) that is inhibited in vivo by a specific rna antitoxin (toxi); however, the mechanisms for this toxicity and inhibition have not been defined. here we present the crystal structure of the toxn-toxi complex from pectobacterium atrosepticum, determined to 2.75-å reso ... | 2011 | 21240270 |
| ligand bound structures of a glycosyl hydrolase family 30 glucuronoxylan xylanohydrolase. | xylanases of glycosyl hydrolase family 30 (gh30) have been shown to cleave β-1,4 linkages of 4-o-methylglucuronoxylan (megx(n)) as directed by the position along the xylan chain of an α-1,2-linked 4-o-methylglucuronate (mega) moiety. complete hydrolysis of megx(n) by these enzymes results in singly substituted aldouronates having a 4-o-methylglucuronate moiety linked to a xylose penultimate from the reducing terminal xylose and some number of xylose residues toward the nonreducing terminus. this ... | 2011 | 21256135 |
| gamma-caprolactone stimulates growth of quorum-quenching rhodococcus populations in a large-scale hydroponic system for culturing solanum tuberosum. | bacteria degrading quorum sensing (qs) signals have been proposed as biocontrol agents able to quench qs-dependent expression of virulence symptoms caused by pectobacterium on potato plants. we report here that gamma-caprolactone (gcl) treatment stimulated growth of the native qs-degrading bacterial community in an industrial plant hydroponic system for culturing solanum tuberosum. post-gcl treatment, qs-degrading bacteria were mainly identified as rhodococcus isolates, while agrobacterium isola ... | 2011 | 21288487 |
| new detection systems of bacteria using highly selective media designed by smart: selective medium-design algorithm restricted by two constraints. | culturing is an indispensable technique in microbiological research, and culturing with selective media has played a crucial role in the detection of pathogenic microorganisms and the isolation of commercially useful microorganisms from environmental samples. although numerous selective media have been developed in empirical studies, unintended microorganisms often grow on such media probably due to the enormous numbers of microorganisms in the environment. here, we present a novel strategy for ... | 2011 | 21304596 |
| transgenic plants expressing the quorum quenching lactonase attm do not significantly alter root-associated bacterial populations. | the possible impact of genetically engineered plants that degrade the quorum sensing (qs) signal of the plant pathogen pectobacterium carotovorum was evaluated on non-target plant-associated bacterial populations and communities using nicotiana tabacum lines expressing the lactonase attm that degrades qs signals (attm), and the wild type (wt) parent line. cell densities of total culturable bacteria and those of selected populations (pseudomonads, agrobacteria) isolated from plant rhizospheres an ... | 2011 | 21315818 |
| complete genome sequence of bacillus subtilis bsn5, an endophytic bacterium of amorphophallus konjac with antimicrobial activity for the plant pathogen erwinia carotovora subsp. carotovora. | here, we present the complete genome sequence of bacillus subtilis strain bsn5, isolated from amorphophallus konjac calli tissue and showing strong inhibitory activity to erwinia carotovora subsp. carotovora, which causes amorphophallus soft rot disease and affects the industry development of this organism. | 2011 | 21317323 |
| ultrastructural observation on sterilization of melittin. | abstact: the effects of melittin on growth and bacteriostasis of four pathogens were extensively investigated using scanning electron microscopy (sem) and transmission electron microscopy (tem). the results indicated that the melittin had a marked bacteriostatic effect on the four pathogenic bacteria. among these, e. cacotowora was influenced most powerfully and quickly, the yeast and f. fulva were the second, and the s. aureus was inhibited by a low concentration but was killed by a high concen ... | 2011 | 21318487 |
| origin and examination of a leafhopper facultative endosymbiont. | eukaryotes engage in intimate interactions with microbes that range in age and type of association. although many conspicuous examples of ancient insect associates are studied (e.g., buchnera aphidicola), fewer examples of younger associations are known. here, we further characterize a recently evolved bacterial endosymbiont of the leafhopper euscelidius variegatus (hemiptera, cicadellidae), called bev. we found that bev, continuously maintained in e. variegatus hosts at uc berkeley since 1984, ... | 2011 | 21336565 |
| effect of medium composition and kinetic studies on extracellular and intracellular production of l-asparaginase from pectobacterium carotovorum. | microbial l-asparaginase occupies a prominent place among biocatalysts owing to their ability to catalyze the reaction that hydrolyze the asparagine molecule. effect of various medium components on the production of l-asparaginase in submerged fermentation by pectobacterium carotovorum was studied for optimal nutrient requirements. six different media compositions were tested for the l-asparaginase production keeping fermentation conditions constant at temperature 30 °c, initial ph 7.0 and agita ... | 2010 | 21339127 |
| effect of water activity on the production of volatile organic compounds by muscodor albus and their effect on three pathogens in stored potato. | muscodor albus (xylariaceae, ascomycetes) isolate cz-620 produces antimicrobial volatile organic compounds (voc), which appear to have potential for the control of various postharvest diseases. the effect of water activity (aw) on the production of voc by m. albus culture, and their inhibitory effects on the growth of three pathogens of potato tuber (fusarium sambucinum, helminthosporium solani, and pectobacterium atrosepticum) and the development of diseases caused by the three pathogens (dry r ... | 2010 | 21354528 |
| characterization of an obligate intracellular bacterium in the midgut epithelium of the bulrush bug chilacis typhae (heteroptera, lygaeidae, artheneinae). | many members of the suborder heteroptera have symbiotic bacteria, which are usually found extracellularly in specific sacs or tubular outgrowths of the midgut or intracellularly in mycetomes. in this study, we describe the second molecular characterization of a symbiotic bacterium in a monophagous, seed-sucking stink bug of the family lygaeidae (sensu stricto). chilacis typhae possesses at the end of the first section of the midgut a structure which is composed of circularly arranged, strongly e ... | 2011 | 21378044 |
| regulation of type vi secretion gene clusters by sigma54 and cognate enhancer binding proteins. | type vi secretion systems (t6ss) are bacteriophage-derived macromolecular machines responsible for the release of at least two proteins in the milieu, which are thought to form an extracellular appendage. although several t6ss have been shown to be involved in the virulence of animal and plant pathogens, clusters encoding these machines are found in the genomes of most species of gram-negative bacteria, including soil, marine, and environmental isolates. t6ss have been associated with several ph ... | 2011 | 21378190 |
| [abortive infection in erwinia carotovora, as a source of nanoparticles of phage nature]. | a possibility to obtain nanoparticles of phage nature using abortive phage infection was shown for the first time. it was found out that the nonspecific host erwinia carotovora subsp. carotovora j2 being infected by phage zf 40-rt80, the cells form a 100-fold surplus of capsid structures. using the electron microscope the authors have found two types of phage capsids which differ from each other and have different modal diameters--47.5 and 71.5 nm. the found capsids pack the phage dna which rele ... | 2010 | 21381318 |
| comparison of the diversity of the bacterial communities in the intestinal tract of adult bactrocera dorsalis from three different populations. | to (i) identify the bacterial communities in the gut of oriental fruit fly (bactrocera dorsalis) adult and (ii) determine whether the different surroundings and diets influence the bacteria composition. | 2011 | 21395953 |
| [transgenic belarussian-bred potato plants expressing genes for antimicrobial peptides of the cecropin-melittin type]. | binary vectors for agrobacterium-mediated transformation were constructed to express the genes for antimicrobial peptides (aps) of the cectropin-melittin type under the control of the cauliflower mosaic virus 35s rna promoter in plants. it was shown with escherichia coli and agrobacterium tumefaciens cells that the cassettes could be cloned in pb1121-based vectors with deletion of the 3-d-glycuronidase gene only in the orientation opposite to that of the original vector. transgenic potato plants ... | 2010 | 21434415 |
| the serratia luxr family regulator carr 39006 activates transcription independently of cognate quorum sensing signals. | in gram-negative bacteria, quorum sensing control of gene expression is mediated by transcription factors of the luxr family, whose dna-binding affinity is modulated by diffusible n-acyl homoserine lactone (ahl) signalling molecules. in serratia sp. atcc 39006 and the plant pathogen erwinia carotovora ssp. carotovora (ecc), the biosynthesis of the +¦-lactam antibiotic 1-carbapen-2-em-3-carboxylic acid (car) is under quorum sensing control. this study has revealed that, uniquely, the luxr family ... | 2011 | 21435033 |
| [transduction as one of the methods of obtaining genetic information in erwinia]. | transduction is one of the key processes of horizontal transfer of genes in bacteria. it is known that it is involved in distribution of the main factors of pathogenicity among numerous enterobacteria. it is shown that clear mutants and some variants of the temperate bacteriophage zf40 erwinia carotovora subsp. carotovora can perform general transduction of chromosome and plasmid genes of the bacterium e. carotovora. the indicators of chromosome transduction frequencies of the markers--arg+, met ... | 2011 | 21442953 |
| optimization of biomass composition explains microbial growth-stoichiometry relationships. | integrating microbial physiology and biomass stoichiometry opens far-reaching possibilities for linking microbial dynamics to ecosystem processes. for example, the growth-rate hypothesis (grh) predicts positive correlations among growth rate, rna content, and biomass phosphorus (p) content. such relationships have been used to infer patterns of microbial activity, resource availability, and nutrient recycling in ecosystems. however, for microorganisms it is unclear under which resource condition ... | 2011 | 21460549 |
| pectobacterium carotovorum elicits plant cell death with dspe/f but the p. carotovorum dspe does not suppress callose or induce expression of plant genes early in plant-microbe interactions. | the broad-host-range bacterial soft rot pathogen pectobacterium carotovorum causes a dspe/f-dependent plant cell death on nicotiana benthamiana within 24 h postinoculation (hpi) followed by leaf maceration within 48 hpi. p. carotovorum strains with mutations in type iii secretion system (t3ss) regulatory and structural genes, including the dspe/f operon, did not cause hypersensitive response (hr)-like cell death and or leaf maceration. a strain with a mutation in the type ii secretion system cau ... | 2011 | 21469936 |
| csy4 is responsible for crispr rna processing in pectobacterium atrosepticum. | crispr/cas systems provide bacteria and archaea with small rna-based adaptive immunity against foreign elements such as phages and plasmids. an important step in the resistance mechanism involves the generation of small guide rnas (crrnas) that, in combination with cas proteins, recognize and inhibit foreign nucleic acids in a sequence specific manner. the generation of crrnas requires processing of the primary crispr rna by an endoribonuclease. in this study we have characterized the ypest subt ... | 2011 | 21519197 |
| classification of plant associated bacteria using rif, a computationally derived dna marker. | a dna marker that distinguishes plant associated bacteria at the species level and below was derived by comparing six sequenced genomes of xanthomonas, a genus that contains many important phytopathogens. this dna marker comprises a portion of the dnaa replication initiation factor (rif). unlike the rrna genes, dnaa is a single copy gene in the vast majority of sequenced bacterial genomes, and amplification of rif requires genus-specific primers. in silico analysis revealed that rif has equal or ... | 2011 | 21533033 |
| chrysobactin siderophores produced by dickeya chrysanthemi ec16. | the plant pathogen dickeya chrysanthemi ec16 (formerly known as petrobacterium chrysanthemi ec16 and erwinia chrysanthemi ec16) was found to produce a new triscatecholamide siderophore, cyclic trichrysobactin, the related catecholamide compounds, linear trichrysobactin and dichrysobactin, and the previously reported monomeric siderophore unit, chrysobactin. chrysobactin is comprised of l-serine, d-lysine, and 2,3-dihydroxybenzoic acid (dhba). trichrysobactin is a cyclic trimer of chrysobactin jo ... | 2011 | 21545171 |
| cloning, purification, and functional characterization of carocin s2, a ribonuclease bacteriocin produced by pectobacterium carotovorum. | abstract: background: most isolates of pectobacterium carotovorum subsp. carotovorum (pcc) produce bacteriocins. in this study, we have determined that pcc strain f-rif-18 has a chromosomal gene encoding the low-molecular-weight bacteriocin, carocin s2, and that this bacteriocin inhibits the growth of a closely related strain. carocin s2 is inducible by ultraviolet radiation but not by mutagenic agents such as mitomycin c. results: a carocin s2-defective mutant, tf1-2, was obtained by tn5 insert ... | 2011 | 21569432 |
| [structural stability of dna of the transposon derivatives of pca25 plasmid]. | mutants of erwinia carotovora subsp. carotovra 48a carrying plasmid pca25 and its transposon variant and resistant to mitomycin c, nalidixic acid and streptomycin were used in the research. it has been shown that the presence of transposon in plasmid pca25 (strain 48a-7/4b[pca25::tn9]) does not practically affect the frequency of appearance of the stable bacterial mutants under the effect of all three antibiotics. several variants, the plasmid profile of which differs from the initial one were f ... | 2011 | 21598660 |
| [peculiarities of morphogenetical development of virulent mutants of erwiniophage zf40]. | the distortion of morphopoiesis or tail attachment to the capsid is a characteristic feature of morphogenetical development not only of a reproductive infection but also of the lysogenic induction of the defective bacteriophage erwinia carotovora subsp. carotovora (ecc). a model system for studying morphogenetical development and assembling of the virion was created on the basis of the phage zf40 and its two virulent mutants zf40-421 and zf40(5/5), as well as the indicator culture ecc m2-4/50 r1 ... | 2011 | 21598661 |
| lpxc and yafs are the most suitable internal controls to normalize real time rt-qpcr expression in the phytopathogenic bacteria dickeya dadantii. | quantitative rt-pcr is the method of choice for studying, with both sensitivity and accuracy, the expression of genes. a reliable normalization of the data, using several reference genes, is critical for an accurate quantification of gene expression. here, we propose a set of reference genes, of the phytopathogenic bacteria dickeya dadantii and pectobacterium atrosepticum, which are stable in a wide range of growth conditions. | 2011 | 21637857 |
| addition of genes for cellobiase and pectinolytic activity in escherichia coli for fuel ethanol production from pectin-rich lignocellulosic biomass. | ethanologenic escherichia coli strain ko11 was sequentially engineered to contain the klebsiella oxytoca cellobiose phosphotransferase genes (casab) as well as a pectate lyase (pele) from erwinia chrysanthemi, yielding strains ly40a (casab) and jp07 (casab pele), respectively. to obtain an effective secretion of pele, the sec-dependent pathway out genes from e. chrysanthemi were provided on a cosmid to strain jp07 to construct strain jp07c. finally, oligogalacturonide lyase (ogl) from e. chrysan ... | 2011 | 21666025 |
| a structure-based qsar and docking study on imidazo[1,5-a][1,2,4]-triazolo[1,5-d][1,4,]benzodiazepines as selective gaba(a) a5 inverse agonists. | since, three-dimensional (3d) structure of the gaba(a) a5 was not determined, the crystal structure of 2vl0e at 3.3 a° resolution which is a ligand-gated k(+) channel was used as a template in homology modeling and the result was used in molecular dynamic simulation for obtaining its conformation in a water sphere. the resulted conformation of the receptor was used for docking with the most potent of imidazo[1,5-a][1,2,4]-triazolo[1,5-d][1,4,]benzodiazepines drugs to find out binding sites and c ... | 2011 | 21756285 |
| pantoea stewartii subsp. stewartii: lessons learned from a xylem-dwelling pathogen of sweet corn. | pantoea stewartii subsp. stewartii is a gram-negative enteric bacterium that primarily infects sweet corn. studies of this bacterium have provided useful insight into how xylem-dwelling bacteria establish themselves and incite disease in their hosts. pantoea stewartii subsp. stewartii is a remarkable bacterial system for laboratory studies because of its relative ease of propagation and genetic manipulation, and the fact that it appears to employ a minimal number of pathogenicity mechanisms. in ... | 2011 | 21726365 |
| identification and expression analysis of chitinase genes related to biotic stress resistance in brassica. | brassica is a very important vegetable group because of its contribution to human nutrition and consequent economic benefits. however, biotic stress is a major concern for these crops and molecular biology techniques offer the most efficient of approaches to address this concern. chitinase is an important biotic stress resistance-related gene. we identified three genes designated as brassica chitinase like protein (brclp1), brclp2 and brclp3 from a full-length cdna library of brassica rapa cv. o ... | 2011 | 21720758 |
| isoarnottinin 4'-glucoside, a glycosylated coumarin from prangos uloptera, with biological activity. | coumarins are a well-known group of natural products distributed in the plant kingdom especially in the family apiaceae with various biological activities. isoarnottinin 4'-glucoside is a simple glycosylated coumarin found previously in a few genera of apiaceae, and its biological activities have not been previously described in details. in the present paper, the compound was isolated from prangos uloptera (apiaceae) leaves using hplc techniques. antimicrobial, phytotoxic and cytotoxic activitie ... | 2011 | 21717896 |
| cora, the magnesium/nickel/cobalt transporter, affects virulence and extracellular enzyme production in the soft rot pathogen pectobacterium carotovorum. | pectobacterium carotovorum (formerly erwinia carotovora ssp. carotovora) is a phytopathogenic bacterium that causes soft rot disease, characterized by water-soaked soft decay, resulting from the action of cell wall-degrading exoenzymes secreted by the pathogen. virulence in soft rot bacteria is regulated by environmental factors, host and bacterial chemical signals, and a network of global and gene-specific bacterial regulators. we isolated a mini-tn5 mutant of p. carotovorum that is reduced in ... | 2011 | 21726393 |
| Ligand activation of the prokaryotic pentameric ligand-gated ion channel ELIC. | While the pentameric ligand-gated ion channel ELIC has recently provided first insight into the architecture of the family at high resolution, its detailed investigation was so far prevented by the fact that activating ligands were unknown. Here we describe a study on the functional characterization of ELIC by electrophysiology and X-ray crystallography. ELIC is activated by a class of primary amines that include the neurotransmitter GABA at high micro- to millimolar concentrations. The ligands ... | 2011 | 21713033 |
| n-acetylglucosamine-dependent biofilm formation in pectobacterium atrosepticum is cryptic and activated by elevated c-di-gmp levels. | the phytopathogenic bacterium pectobacterium atrosepticum (pba) strain scri1043 does not exhibit appreciable biofilm formation under standard laboratory conditions. here we show that a biofilm-forming phenotype in this strain could be activated from a cryptic state by increasing intracellular levels of c-di-gmp, through overexpression of a constitutively active diguanylate cyclase (pled*) from caulobacter crescentus. randomly obtained pba transposon mutants defective in the pga operon, involved ... | 2011 | 21948048 |
| Proposal to reclassify Brenneria quercina (Hildebrand & Schroth 1967) Hauben et al. 1999 into a novel genus, Lonsdalea gen. nov., as Lonsdalea quercina comb. nov., descriptions of Lonsdalea quercina subsp. quercina comb. nov., Lonsdalea quercina subsp. iberica subsp. nov. and Lonsdalea quercina subsp. britannica subsp. nov., emendation of the description of the genus Brenneria, reclassification of Dickeya dieffenbachiae as Dickeya dadantii subsp. dieffenbachiae comb. nov., and emendation of the description of Dickeya dadantii. | Bacterial isolates from oak in Spain and Britain, showing symptoms of bark canker and Acute Oak Decline (AOD) respectively, were examined by a polyphasic approach. Both 16S rRNA gene sequencing and multilocus sequence analysis (MLSA), based on partial sequences of gyrB, rpoB, infB and atpD, revealed that the isolates were separated into two genetic groups according to their origin. Their closest phylogenetic relative was B. quercina, the causal agent of drippy nut disease of oak, which clustered ... | 2011 | 21890733 |
| attenuation of virulence in pathogenic bacteria using synthetic quorum-sensing modulators under native conditions on plant hosts. | quorum sensing (qs) is often critical in both pathogenic and mutualistic relationships between bacteria and their eukaryotic hosts. gram-negative bacteria typically use n-acylated l-homoserine lactone (ahl) signals for qs. we have identified a number of synthetic ahl analogues that are able to strongly modulate qs in culture-based, reporter gene assays. while informative, these assays represent idealized systems, and their relevance to qs under native conditions is often unclear. as one of our g ... | 2011 | 21932837 |
| quantitative resistance of potato to pectobacterium atrosepticum and phytophthora infestans: integrating pamp-triggered response and pathogen growth. | while the mechanisms underlying quantitative resistance of plants to pathogens are still not fully elucidated, the pathogen-associated molecular patterns (pamps)-triggered response model suggests that such resistance depends on a dynamic interplay between the plant and the pathogen. in this model, the pathogens themselves or elicitors they produce would induce general defense pathways, which in turn limit pathogen growth and host colonisation. it therefore suggests that quantitative resistance i ... | 2011 | 21853112 |
| definition of the common and divergent steps in carbapenem β-lactam antibiotic biosynthesis. | approximately 50 naturally occurring carbapenem β-lactam antibiotics are known. all but one of these have been isolated from streptomyces species and are disubstituted structural variants of a simple core that is synthesized by pectobacterium carotovorum (erwinia carotovora), a phylogenetically distant plant pathogen. while the biosynthesis of the simple carbapenem, (5r)-carbapen-2-em-3-carboxylic acid, is impressively efficient requiring only three enzymes, cara, carb and carc, the formation of ... | 2011 | 21913298 |
| efficient biostimulation of native and introduced quorum-quenching rhodococcus erythropolis populations is revealed by a combination of analytical chemistry, microbiology, and pyrosequencing. | degradation of the quorum-sensing (qs) signals known as n-acylhomoserine lactones (ahl) by soil bacteria may be useful as a beneficial trait for protecting crops, such as potato plants, against the worldwide pathogen pectobacterium. in this work, analytical chemistry and microbial and molecular approaches were combined to explore and compare biostimulation of native and introduced ahl-degrading rhodococcus erythropolis populations in the rhizosphere of potato plants cultivated in farm greenhouse ... | 2012 | 22081576 |
| Interactions among Glomus irregulare, arbuscular mycorrhizal spore-associated bacteria, and plant pathogens under in vitro conditions. | Arbuscular mycorrhizal (AM) fungi interact with bacteria (AM fungi-associated bacteria, AMB) in the mycorrhizosphere. We previously identified a set of AMB that enhance AM fungal colonization, plant growth, and inhibit pathogens. Here, we used transformed carrot root cultures in a two-compartment plate system for further in vitro studies on interactions taking place among Glomus irregulare (syn.Glomus intraradices), AMB, and plant pathogens. We found that exudates of G. irregulare stimulated gro ... | 2011 | 22081167 |
| Chemical structure of the O-polysaccharide isolated from Pectobacterium atrosepticum SCRI 1039. | The lipopolysaccharide (LPS) of the bacterium Pectobacterium atrosepticum SCRI 1039 was hydrolyzed and the products were separated. A study of the obtained O-polysaccharide by means of chemical methods, GLC, GLC-MS, and NMR spectroscopy allowed us to identify a branched polymer with a pentasaccharide repeating unit of the structure shown below, in which the fucose residue was partially O-acetylated at C-2, C-3 or C-4. | 2011 | 22074675 |
| a multi-repeat adhesin of the phytopathogen, pectobacterium atrosepticum, is secreted by a type i pathway and is subject to complex regulation involving a non-canonical diguanylate cyclase. | cyclic diguanylate (c-di-gmp) is a second messenger controlling many important bacterial processes. the phytopathogen pectobacterium atrosepticum scri1043 (pba1043) possesses a type i secretion system (t1ss) essential for the secretion of a proteinaceous multi-repeat adhesin (mrp) required for binding to the host plant. the genes encoding the mrp and the t1ss are tightly linked to genes encoding several putative c-di-gmp regulatory components. we show that c-di-gmp regulates secreted mrp levels ... | 2011 | 21992096 |
| complete genome sequence and characterization of the n-acylhomoserine lactone-degrading gene of the potato leaf-associated solibacillus silvestris. | n-acylhomoserine lactones (ahls) are used as quorum-sensing signal molecules by many gram-negative bacteria. we have reported that solibacillus silvestris, which was isolated from the potato leaf, has ahl-degrading activity. to identify the ahl-degrading gene, whole genome sequencing of s. silvestris stlb046 was performed by using pyrosequencing technology. as the result of the blast search, one predicted orf (ahls) showed slight similarity to aiia-like ahl lactonase from bacillus cereus group. ... | 2011 | 22019407 |
| the culturable intestinal microbiota of triploid and diploid juvenile atlantic salmon (salmo salar) - a comparison of composition and drug resistance. | with the increased use of ploidy manipulation in aquaculture and fisheries management this investigation aimed to determine whether triploidy influences culturable intestinal microbiota composition and bacterial drug resistance in atlantic salmon (salmo salar). the results could provide answers to some of the physiological differences observed between triploid and diploid fish, especially in terms of fish health. | 2011 | 22094054 |
| culture independent survey of the microbiota of the glassy-winged sharpshooter (homalodisca vitripennis) using 454 pyrosequencing. | the glassy-winged sharpshooter, homalodisca vitripennis (germar), is an invasive pest that has spread across the southern and western united states. h. vitripennis is highly polyphagous and voracious, feeding on at least 100 plant species and consuming up to 100 times its weight in xylem fluid daily. the insect is a vector of the phytopathogen xylella fastidiosa (wells), which is the causative agent of pierce's disease in grapevines. to evaluate the microbial flora associated with h. vitripenni ... | 2011 | 22182607 |
| studies on ph and thermal stability of novel purified l-asparaginase from pectobacterium carotojorum mtcc 1428. | glutaminase free l-asparaginase is known to be an excellent anticancer agent. in the present study, the combined effect of ph and temperature on the performance of purified novel l-asparaginase from pectobacterium carotovorum mtcc 1428 was studied under assay conditions using response surface methodology (rsm). deactivation studies and thermodynamic parameters of this therapeutically important enzyme were also investigated. the optimum ph and temperature of the purified l-asparaginase were found ... | 2011 | 21861371 |
| genetic evidence for a protective role of the peritrophic matrix against intestinal bacterial infection in drosophila melanogaster. | the peritrophic matrix (pm) forms a layer composed of chitin and glycoproteins that lines the insect intestinal lumen. this physical barrier plays a role analogous to that of mucous secretions of the vertebrate digestive tract and is thought to protect the midgut epithelium from abrasive food particles and microbes. almost nothing is known about pm functions in drosophila, and its function as an immune barrier has never been addressed by a genetic approach. here we show that the drosocrystallin ... | 2011 | 21896728 |
| the 3-hydroxy-2-butanone pathway is required for pectobacterium carotovorum pathogenesis. | pectobacterium species are necrotrophic bacterial pathogens that cause soft rot diseases in potatoes and several other crops worldwide. gene expression data identified pectobacterium carotovorum subsp. carotovorum budb, which encodes the α-acetolactate synthase enzyme in the 2,3-butanediol pathway, as more highly expressed in potato tubers than potato stems. this pathway is of interest because volatiles produced by the 2,3-butanediol pathway have been shown to act as plant growth promoting molec ... | 2011 | 21876734 |
| [Polypeptide content and HPLC-chromatpgrahy of the virions of phage ZF40 mutants]. | Study of the polypeptide content of erwiniophage ZF40c(5/5) and ZF40-421 virulent mutants has shown that their virions include no less than 10 structural proteins with molecular weights ranging from 16.9 to 96.5 kDa. Three polypeptides belong to a group of major proteins with molecular weights 39.2, 33.1 and 18.5 kDa. They correlate with the polypeptides of phage head, tail sheath and tail core correspondingly. It has been proven that the protein contents of these phages are identical, taking in ... | 2011 | 22164700 |
| pecs is an important player in the regulatory network governing the coordinated expression of virulence genes during the interaction between dickeya dadantii 3937 and plants. | successful infection of a pathogen relies on the coordinated expression of numerous virulence factor-encoding genes. in plant-bacteria interactions, this control is very often achieved through the integration of several regulatory circuits controlling cell-cell communication or sensing environmental conditions. dickeya dadantii (formerly erwinia chrysanthemi), the causal agent of soft rot on many crops and ornamentals, provokes maceration of infected plants mainly by producing and secreting a ba ... | 2011 | 21906221 |
| The Iturin-like Lipopeptides Are Essential Components in the Biological Control Arsenal of Bacillus subtilis Against Bacterial Diseases of Cucurbits. | The antibacterial potential of four strains of Bacillus subtilis, UMAF6614, UMAF6619, UMAF6639, and UMAF8561, previously selected on the basis of their antifungal activity and efficacy against cucurbit powdery mildew, was examined. Among these strains, UMAF6614 and UMAF6639 showed the highest antibacterial activity in vitro, especially against Xanthomonas campestris pv. cucurbitae and Pectobacterium carotovorum subsp. carotovorum. These strains produced the three families of lipopeptide antibiot ... | 2011 | 22066902 |
| multiple origins of endosymbiosis within the enterobacteriaceae (gamma-proteobacteria): convergence of complex phylogenetic approaches. | abstract: background: the bacterial family enterobacteriaceae gave rise to a variety of symbiotic forms, from the loosely associated commensals, often designated as secondary (s) symbionts, to obligate mutualists, called primary (p) symbionts. determination of the evolutionary processes behind this phenomenon has long been hampered by the unreliability of phylogenetic reconstructions within this group of bacteria. the main reasons have been the absence of sufficient data, the highly derived nat ... | 2011 | 22201529 |
| microbial diversity inside pumpkins: microhabitat-specific communities display a high antagonistic potential against phytopathogens. | recent and substantial yield losses of styrian oil pumpkin (cucurbita pepo l. subsp. pepo var. styriaca greb.) are primarily caused by the ascomycetous fungus didymella bryoniae but bacterial pathogens are frequently involved as well. the diversity of endophytic microbial communities from seeds (spermosphere), roots (endorhiza), flowers (anthosphere), and fruits (carposphere) of three different pumpkin cultivars was studied to develop a biocontrol strategy. a multiphasic approach combining molec ... | 2011 | 21947430 |
| draft genome sequence of the biocontrol bacterium pseudomonas putida b001, an oligotrophic bacterium that induces systemic resistance to plant diseases. | pseudomonas putida b001 is a rhizobacterium that was isolated on the basis of its abilities to grow under low-nutrient conditions and induce systemic resistance against bacterial, fungal, and viral diseases of plants. here we report the draft genome sequence and automatic annotation of strain b001. comparison of this sequence to the sequenced genome of p. putida kt2440 points to a subset of gene functions that may be related to the defense-inducing functions of b001. | 2011 | 22072649 |
| massive production of butanediol during plant infection by phytopathogenic bacteria of the genera dickeya and pectobacterium. | plant pathogenic bacteria of the genera dickeya and pectobacterium are broad-host-range necrotrophs which cause soft-rot diseases in important crops. a metabolomic analysis, based on (13)c-nmr spectroscopy, was used to characterize the plant-bacteria interaction. metabolic profiles revealed a decline in plant sugars and amino acids during infection and the concomitant appearance of a compound identified as 2,3-butanediol. butanediol is the major metabolite found in macerated tissues of various h ... | 2011 | 22032684 |
| slya regulates t3ss genes in parallel with the t3ss master regulator hrpl in dickeya dadantii 3937. | the hrp (hypersensitive response and pathogenicity) genes of dickeya dadantii 3937 encode a type iii secretion system (t3ss) which is essential for its full virulence. previous studies of the t3ss regulation in d. dadantii 3937 revealed that the expression of the hrp genes is regulated by a master regulator hrpl through the hrpx-hrpy-hrps-hrpl and gacs-gaca-rsmb-rsma pathways. in this work, we identified a novel regulator of the slya/marr family, slya, which regulates hrp genes of the hrpl regul ... | 2012 | 22267675 |