Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| toll-8/tollo negatively regulates antimicrobial response in the drosophila respiratory epithelium. | barrier epithelia that are persistently exposed to microbes have evolved potent immune tools to eliminate such pathogens. if mechanisms that control drosophila systemic responses are well-characterized, the epithelial immune responses remain poorly understood. here, we performed a genetic dissection of the cascades activated during the immune response of the drosophila airway epithelium i.e. trachea. we present evidence that bacteria induced-antimicrobial peptide (amp) production in the trachea ... | 2011 | 22022271 |
| Growth Inhibition of Various Enterobacteriaceae Species by the Yeast Hansenula anomala during Storage of Moist Cereal Grain. | Eleven of 13 Enterobacteriaceae species tested grew in moist stored wheat, highlighting a potential risk of this energy-saving airtight storage method. When Hansenula anomala was coinoculated, all Enterobacteriaceae species were significantly inhibited after 2 months of storage, six of them to below the detection limit. | 2012 | 22020520 |
| 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 |
| Processing and Maturation of the Pilin of the Type IV Secretion System Encoded within the Gonococcal Genetic Island. | The type IV secretion system (T4SS) encoded within the gonococcal genetic island (GGI) of Neisseria gonorrhoeae has homology to the T4SS encoded on the F plasmid. The GGI encodes the putative pilin protein TraA and a serine protease TrbI, which is homologous to the TraF protein of the RP4 plasmid involved in circularization of pilin subunits of P-type pili. TraA was processed to a 68-amino acid long circular peptide by leader peptidase and TrbI. Processing occurred after co-translational membran ... | 2011 | 22006923 |
| functional characterization and biological significance of yersinia pestis lipopolysaccharide biosynthesis genes. | in silico analysis of available bacterial genomes revealed the phylogenetic proximity levels of enzymes responsible for biosynthesis of lipopolysaccharide (lps) of yersinia pestis, the cause of plague, to homologous proteins of closely related yersinia spp. and some other bacteria (serratia proteamaculans, erwinia carotovora, burkholderia dolosa, photorhabdus luminescens and others). isogenic y. pestis mutants with single or double mutations in 14 genes of lps biosynthetic pathways were construc ... | 2011 | 21999543 |
| a resistance gene against potato late blight originating from solanum × michoacanum maps to potato chromosome vii. | solanum × michoacanum (bitter.) rydb. is a diploid, 1 ebn (endosperm balance number) nothospecies, a relative of potato originating from the area of morelia in michoacán state of mexico that is believed to be a natural hybrid of s. bulbocastanum × s. pinnatisectum. both parental species and s. michoacanum have been described as sources of resistance to phytophthora infestans (mont.) de bary. the gene for resistance to potato late blight, rpi-mch1, originating from s. michoacanum was mapped to t ... | 2011 | 21987281 |
| a resistance gene against potato late blight originating from solanum × michoacanum maps to potato chromosome vii. | solanum × michoacanum (bitter.) rydb. is a diploid, 1 ebn (endosperm balance number) nothospecies, a relative of potato originating from the area of morelia in michoacán state of mexico that is believed to be a natural hybrid of s. bulbocastanum × s. pinnatisectum. both parental species and s. michoacanum have been described as sources of resistance to phytophthora infestans (mont.) de bary. the gene for resistance to potato late blight, rpi-mch1, originating from s. michoacanum was mapped to t ... | 2011 | 21987281 |
| kdgr, an iclr family transcriptional regulator, inhibits virulence mainly by repression of hrp genes in xanthomonas oryzae pv. oryzae. | kdgr has been reported to negatively regulate the genes involved in degradation and metabolization of pectic acid and other extracellular enzymes in soft-rotting erwinia spp. through direct binding to their promoters. the possible involvement of a kdgr orthologue in virulence by affecting the expression of extracellular enzymes in xanthomonas oryzae pv. oryzae, the causal agent of rice blight disease, was examined by comparing virulence and regulation of extracellular enzymes between the wild ty ... | 2011 | 21984784 |
| wolbachia-mediated antibacterial protection and immune gene regulation in drosophila. | the outcome of microbial infection of insects is dependent not only on interactions between the host and pathogen, but also on the interactions between microbes that co-infect the host. recently the maternally inherited endosymbiotic bacteria wolbachia has been shown to protect insects from a range of microbial and eukaryotic pathogens. mosquitoes experimentally infected with wolbachia have upregulated immune responses and are protected from a number of pathogens including viruses, bacteria, pla ... | 2011 | 21980455 |
| the orphan gene ybjn conveys pleiotropic effects on multicellular behavior and survival of escherichia coli. | ybjn, encoding an enterobacteria-specific protein, is a multicopy suppressor of temperature sensitivity in the ts9 mutant strain of escherichia coli. in this study, we further explored the role(s) of ybjn. first, we demonstrated that the ybjn transcript was about 10-fold lower in the ts9 strain compared to that of e. coli strain bw25113 (bw). introduction of multiple copies of ybjn in the ts9 strain resulted in over-expression of ybjn by about 10-fold as compared to that of bw. these results sug ... | 2011 | 21980417 |
| deconstructing host-pathogen interactions in drosophila. | many of the cellular mechanisms underlying host responses to pathogens have been well conserved during evolution. as a result, drosophila can be used to deconstruct many of the key events in host-pathogen interactions by using a wealth of well-developed molecular and genetic tools. in this review, we aim to emphasize the great leverage provided by the suite of genomic and classical genetic approaches available in flies for decoding details of host-pathogen interactions; these findings can then b ... | 2011 | 21979942 |
| deconstructing host-pathogen interactions in drosophila. | many of the cellular mechanisms underlying host responses to pathogens have been well conserved during evolution. as a result, drosophila can be used to deconstruct many of the key events in host-pathogen interactions by using a wealth of well-developed molecular and genetic tools. in this review, we aim to emphasize the great leverage provided by the suite of genomic and classical genetic approaches available in flies for decoding details of host-pathogen interactions; these findings can then b ... | 2011 | 21979942 |
| biophysical investigations into the interactions of endotoxins with bile acids. | the interaction of selected endotoxin preparations (lipid a from erwinia carotovora and lps re and ra from salmonella enterica sv. minnesota strains r595 and r60, respectively) with selected bile acids was investigated biophysically. endotoxin aggregates were analyzed for their gel-to-liquid crystalline phase behavior, the type of their aggregates, the conformation of particular functional groups, and their zeta potential in the absence and presence of the bile acids by applying fourier-transfor ... | 2011 | 21954318 |
| probing the impact of ligand binding on the acyl-homoserine lactone-hindered transcription factor esar of pantoea stewartii subsp. stewartii. | the quorum-sensing regulator esar from pantoea stewartii subsp. stewartii is a luxr homologue that is inactivated by acyl-homoserine lactone (ahl). in the corn pathogen p. stewartii, production of exopolysaccharide (eps) is repressed by esar at low cell densities. however, at high cell densities when high concentrations of its cognate ahl signal are present, esar is inactivated and derepression of eps production occurs. thus, esar responds to ahl in a manner opposite to that of most luxr family ... | 2011 | 21949066 |
| 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 |
| analysis of the biofilm proteome of xylella fastidiosa. | abstract: | 2011 | 21939513 |
| The priB gene of Klebsiella pneumoniae encodes a 104-amino acid protein that is similar in structure and function to Escherichia coli PriB. | Primosome protein PriB is a single-stranded DNA-binding protein that serves as an accessory factor for PriA helicase-catalyzed origin-independent reinitiation of DNA replication in bacteria. A recent report describes the identification of a novel PriB protein in Klebsiella pneumoniae that is significantly shorter than most sequenced PriB homologs. The K. pneumoniae PriB protein is proposed to comprise 55 amino acid residues, in contrast to E. coli PriB which comprises 104 amino acid residues and ... | 2011 | 21931731 |
| analysis of the bara/uvry two-component system in shewanella oneidensis mr-1. | the bara/uvry two-component system is well conserved in species of the γ-proteobacteria and regulates numerous processes predominantly by controlling the expression of a subset of noncoding small rnas. in this study, we identified and characterized the bara/uvry two-component system in the gammaproteobacterium shewanella oneidensis mr-1. functional interaction of sensor kinase bara and the cognate response regulator uvry was indicated by in vitro phosphotransfer studies. the expression of two pr ... | 2011 | 21931597 |
| 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 |
| Identification, tissue distribution, and molecular modeling of novel human isoforms of the key enzyme in sialic acid synthesis, UDP-GlcNAc 2-epimerase/ManNAc kinase. | UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE) catalyzes the first two committed steps in sialic acid synthesis. In addition to the three previously described human GNE isoforms (hGNE1-hGNE3), our database and polymerase chain reaction analysis yielded five additional human isoforms (hGNE4-hGNE8). hGNE1 is the ubiquitously expressed major isoform, while the hGNE2-hGNE8 isoforms are differentially expressed and may act as tissue-specific regulators of sialylation. hGNE2 and hGNE7 display a 31-residue ... | 2011 | 21910480 |
| using orthomcl to assign proteins to orthomcl-db groups or to cluster proteomes into new ortholog groups. | orthomcl is an algorithm for grouping proteins into ortholog groups based on their sequence similarity. orthomcl-db is a public database that allows users to browse and view ortholog groups that were pre-computed using the orthomcl algorithm. version 4 of this database contained 116,536 ortholog groups clustered from 1,270,853 proteins obtained from 88 eukaryotic genomes, 16 archaean genomes, and 34 bacterial genomes. future versions of orthomcl-db will include more proteomes as more genomes are ... | 2011 | 21901743 |
| 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 opportunistic pathogen Serratia marcescens utilizes type VI secretion to target bacterial competitors. | The type VI secretion system (T6SS) is the most recently described and least understood of the protein secretion systems of Gram-negative bacteria. It is widely distributed and has been implicated in the virulence of various pathogens, but its mechanism and exact mode of action remain to be defined. Additionally there have been several very recent reports that some T6SSs can target bacteria rather than eukaryotic cells. Serratia marcescens is an opportunistic enteric pathogen, a class of bacteri ... | 2011 | 21890705 |
| a common evolutionary origin for tailed-bacteriophage functional modules and bacterial machineries. | bacteriophages belonging to the order caudovirales possess a tail acting as a molecular nanomachine used during infection to recognize the host cell wall, attach to it, pierce it, and ensure the high-efficiency delivery of the genomic dna to the host cytoplasm. in this review, we provide a comprehensive analysis of the various proteins constituting tailed bacteriophages from a structural viewpoint. to this end, we had in mind to pinpoint the resemblances within and between functional modules suc ... | 2011 | 21885679 |
| 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 |
| the involvement of jasmonates and ethylene in alternaria alternata f. sp. lycopersici toxin-induced tomato cell death. | previous studies have shown that an ethylene (et)-dependent pathway is involved in the cell death signalling triggered by alternaria alternata f. sp. lycopersici (aal) toxin in detached tomato (solanum lycopersicum) leaves. in this study, the role of jasmonic acid (ja) signalling in programmed cell death (pcd) induced by aal toxin was analysed using a 35s::prosystemin transgenic line (35s::prosys), a ja-deficient mutant spr2, and a ja-insensitive mutant jai1. the results indicated that ja biosyn ... | 2011 | 21865178 |
| 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 |
| pyrroloquinoline quinone biosynthesis gene pqqc, a novel molecular marker for studying the phylogeny and diversity of phosphate-solubilizing pseudomonads. | many root-colonizing pseudomonads are able to promote plant growth by increasing phosphate availability in soil through solubilization of poorly soluble rock phosphates. the major mechanism of phosphate solubilization by pseudomonads is the secretion of gluconic acid, which requires the enzyme glucose dehydrogenase and its cofactor pyrroloquinoline quinone (pqq). the main aim of this study was to evaluate whether a pqq biosynthetic gene is suitable to study the phylogeny of phosphate-solubilizin ... | 2011 | 21856827 |
| coordinate control of the locus of enterocyte effacement and enterohemolysin genes by multiple common virulence regulators in enterohemorrhagic escherichia coli. | the locus of enterocyte effacement (lee) pathogenicity island is required for the intimate adhesion of enterohemorrhagic escherichia coli (ehec) to the intestinal epithelial cells. grlr and grla are lee-encoded negative and positive regulators, respectively. the interaction of these two regulators is important for controlling the transcription of lee genes through ler, a lee-encoded central activator for the lee. the grlr-grla regulatory system controls not only lee, but also the expression of t ... | 2011 | 21844237 |
| antibiotics as signal molecules. | 2011 | 21786783 | |
| two new complete genome sequences offer insight into host and tissue specificity of plant pathogenic xanthomonas spp. | xanthomonas is a large genus of bacteria that collectively cause disease on more than three hundred plant species. the broad host range of the genus contrasts with stringent host and tissue-specificity for individual species and pathovars. whole genome sequences of x. campestris pv. raphani strain 756c and x. oryzae pv. oryzicola strain bls256, pathogens that infect the mesophyll tissue of the leading models for plant biology, arabidopsis thaliana and rice, respectively, were determined that pro ... | 2011 | 21784931 |
| 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 |
| negative regulation of defence signalling pathways by the edr1 protein kinase. | the enhanced disease resistance 1 (edr1) mutant of arabidopsis confers enhanced resistance to bacterial and fungal pathogens. to better understand how edr1-mediated resistance occurs, we performed transcriptome analyses on wild-type and edr1 plants inoculated with the fungal pathogen golovinomyces cichoracearum (powdery mildew). the expression of many known and putative defence-associated genes was more rapidly induced, and to higher levels, in edr1 plants relative to the wild-type. many of the ... | 2011 | 21726375 |
| 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 |
| structure and function of the d-galactose network in enterobacteria. | galactose is important for the survival and virulence of bacteria. in escherichia coli, galactose is utilized by the leloir pathway, which is controlled by a complex network. to shed light on the potential functions the galactose network could perform, we performed bioinformatical analysis of reference genome sequences belonging to the enterobacteriaceae family. we found that several genomes have reduced numbers of components compared to the e. coli galactose system, suggesting that the network ... | 2011 | 21712421 |
| identification of xanthomonas fragariae, xanthomonas axonopodis pv. phaseoli, and xanthomonas fuscans subsp. fuscans with novel markers and using a dot blot platform coupled with automatic data analysis. | phytosanitary regulations and the provision of plant health certificates still rely mainly on long and laborious culture-based methods of diagnosis, which are frequently inconclusive. dna-based methods of detection can circumvent many of the limitations of currently used screening methods, allowing a fast and accurate monitoring of samples. the genus xanthomonas includes 13 phytopathogenic quarantine organisms for which improved methods of diagnosis are needed. in this work, we propose 21 new xa ... | 2011 | 21705524 |
| arabidopsis cell death in compatible and incompatible interactions with alternaria brassicicola. | two strains of necrotrophic alternaria brassicicola, ab40857 and ab42464, are virulent on korean cabbage and several wild types of arabidopsis thaliana. interaction between ab42464 and col-0 was compatible, whereas interaction between ab40857 and col-0 was incompatible. the loss of defense, no death (dnd) 1 function abrogated the compatibility between ab42464 and col-0, and the accelerated cell death (acd) 2 mutation attenuated the col-0's resistance against ab40857. these two fungal strains ind ... | 2011 | 21688205 |
| anti-phytopathogenic activities of macro-algae extracts. | aqueous and ethanolic extracts obtained from nine chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia g ... | 2011 | 21673886 |
| genomic analysis reveals versatile organisms for quorum quenching enzymes: acyl-homoserine lactone-acylase and -lactonase. | microbial virulence and their resistance to multiple drugs have obliged researchers to look for novel drug targets. virulence of pathogenic microbes is regulated by signal molecules such as acylated homoserine lactone (ahl) produced during a cell density dependent phenomenon of quorum sensing (qs). in contrast, certain microbes produce ahl-lactonases and -acylases to degrade qs signals, also termed as quorum quenching. mining sequenced genome databases has revealed organisms possessing conserved ... | 2011 | 21660112 |
| characterization of a small cryptic plasmid from endophytic pantoea agglomerans and its use in the construction of an expression vector. | a circular cryptic plasmid named ppaga (2,734 bp) was isolated from pantoea agglomerans strain ege6 (an endophytic bacterial isolate from eucalyptus). sequence analysis revealed that the plasmid has a g+c content of 51% and contains four potential orfs, 238(a), 250(b), 131(c), and 129(d) amino acids in length without homology to known proteins. the shuttle vector plgm1 was constructed by combining the ppaga plasmid with pgfpmut3.0 (which harbors a gene encoding green fluorescent protein, gfp), a ... | 2011 | 21637551 |
| structural and functional analyses reveal that staphylococcus aureus antibiotic resistance factor hmra is a zinc-dependent endopeptidase. | hmra is an antibiotic resistance factor of methicillin-resistant staphylococcus aureus (mrsa). molecular analysis of this protein revealed it is not a muramidase or β-lactamase but an unspecific double-zinc endopeptidase consisting of a catalytic domain and an inserted oligomerization domain, which likely undergo a relative interdomain hinge rotation upon substrate binding. the active-site cleft is located at the domain interface. four hmra protomers assemble to a large ~170-kda homotetrameric c ... | 2011 | 21622555 |
| bacterial syntenies: an exact approach with gene quorum. | the automatic identification of syntenies across multiple species is a key step in comparative genomics that helps biologists shed light both on evolutionary and functional problems. | 2011 | 21605461 |
| secretion of anti-plasmodium effector proteins from a natural isolate pantoea agglomerans using pelb and hlya secretion signals. | the insect-vectored disease malaria is a major world health problem. new control strategies are needed to supplement the current use of insecticides and medications. a genetic approach can be used to inhibit development of the malaria parasite (plasmodium sp.) in the mosquito host. we hypothesized that pantoea agglomerans, a bacterial symbiont of anopheles mosquitoes, could be engineered to express and secrete anti-plasmodium effector proteins, a strategy termed paratransgenesis. to this end, pl ... | 2011 | 21602368 |
| [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 |
| [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 |
| bacterial symbionts and natural products. | the study of bacterial symbionts of eukaryotic hosts has become a powerful discovery engine for chemistry. this highlight looks at four case studies that exemplify the range of chemistry and biology involved in these symbioses: a bacterial symbiont of a fungus and a marine invertebrate that produce compounds with significant anticancer activity, and bacterial symbionts of insects and nematodes that produce compounds that regulate multilateral symbioses. | 2011 | 21594283 |
| the assembly mode of the pseudopilus: a hallmark to distinguish a novel secretion system subtype. | in gram negative bacteria, type ii secretion systems assemble a piston-like structure, called pseudopilus, which expels exoproteins out of the cell. the pseudopilus is constituted by a major pseudopilin that when overproduced multimerizes into a long cell surface structure named hyper-pseudopilus. pseudomonas aeruginosa possesses two type ii secretion systems, xcp and hxc. while major pseudopilins are exchangeable among type ii secretion systems, we show that xcpt and hxct are not. we demonstrat ... | 2011 | 21586577 |
| 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 |
| pathogen and host factors are needed to provoke a systemic host response to gastrointestinal infection of drosophila larvae by candida albicans. | candida albicans systemic dissemination in immunocompromised patients is thought to develop from initial gastrointestinal (gi) colonisation. it is unclear what components of the innate immune system are necessary for preventing c. albicans dissemination from the gi tract, but studies in mice have indicated that both neutropenia and gi mucosal damage are crucial for allowing widespread invasive c. albicans disease. mouse models, however, provide limited applicability to genome-wide screens for pa ... | 2011 | 21540243 |
| slya is a transcriptional regulator involved in the virulence of enterococcus faecalis. | phylogenetic analysis of the crystal structure of the enterococcus faecalis slya (ef_3002) transcriptional factor places it between the slya and marr regulator subfamilies. proteins of these families are often involved in the regulation of genes important for bacterial virulence and stress response. to gather evidence for the role of this putative regulator in e. faecalis biology, we dissected the genetic organisation of the slya-ef_3001 locus, and constructed slya deletion mutant as well as com ... | 2011 | 21536798 |
| 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 |
| molecular characterization of cronobacter lipopolysaccharide o-antigen gene clusters and development of serotype-specific pcr assays. | cronobacter spp. (formerly enterobacter sakazakii) is a recently defined genus consisting of six species including c. sakazakii, c. malonaticus, c. dublinensis, c. muytjensii, c. turicensis, and cronobacter genomospecies group 1. in this study, mboii restriction fragment length polymorphism (rflp) patterns of o-antigen gene clusters, located between galf and gnd, were used to identify serotypes in cronobacter spp. seven o-antigen rflp clusters were generated including three c. sakazakii clusters ... | 2011 | 21531829 |
| integration of a complex regulatory cascade involving the sira/bara and csr global regulatory systems that controls expression of the salmonella spi-1 and spi-2 virulence regulons through hild. | salmonella pathogenicity islands 1 and 2 (spi-1 and spi-2) play key roles in the pathogenesis of salmonella enterica. previously, we showed that when salmonella grows in luria-bertani medium, hild, encoded in spi-1, first induces the expression of hila, located in spi-1, and subsequently of the ssrab operon, located in spi-2. these genes code for hila and the ssra/b two-component system, the positive regulators of the spi-1 and spi-2 regulons respectively. in this study, we demonstrate that csra ... | 2011 | 21518393 |
| xerr, a negative regulator of xccr in xanthomonas campestris pv. campestris, relieves its repressor function in planta. | we previously reported that xccr, a luxr-type regulator of xanthomonas campestris pv. campestris (xcc), activates the downstream proline iminopeptidase virulence gene (pip) in response to certain host plant factor(s). in this report, we further show that the expression of the xccr gene was repressed in the culture medium by an ntrc-type response regulator, which we named xerr (xccr expression-related, repressor), and that this repression was relieved when the bacteria were grown in planta. such ... | 2011 | 21483448 |
| a novel transcription factor, erd15 (early responsive to dehydration 15), connects endoplasmic reticulum stress with an osmotic stress-induced cell death signal. | as in all other eukaryotic organisms, endoplasmic reticulum (er) stress triggers the evolutionarily conserved unfolded protein response in soybean, but it also communicates with other adaptive signaling responses, such as osmotic stress-induced and er stress-induced programmed cell death. these two signaling pathways converge at the level of gene transcription to activate an integrated cascade that is mediated by n-rich proteins (nrps). here, we describe a novel transcription factor, gmerd15 (gl ... | 2011 | 21482825 |
| 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 |
| n-terminal domain of alphab-crystallin provides a conformational switch for multimerization and structural heterogeneity. | the small heat shock protein (shsp) αb-crystallin (αb) plays a key role in the cellular protection system against stress. for decades, high-resolution structural studies on heterogeneous shsps have been confounded by the polydisperse nature of αb oligomers. we present an atomic-level model of full-length αb as a symmetric 24-subunit multimer based on solid-state nmr, small-angle x-ray scattering (saxs), and em data. the model builds on our recently reported structure of the homodimeric α-crystal ... | 2011 | 21464278 |
| molecular evolution of urea amidolyase and urea carboxylase in fungi. | urea amidolyase breaks down urea into ammonia and carbon dioxide in a two-step process, while another enzyme, urease, does this in a one step-process. urea amidolyase has been found only in some fungal species among eukaryotes. it contains two major domains: the amidase and urea carboxylase domains. a shorter form of urea amidolyase is known as urea carboxylase and has no amidase domain. eukaryotic urea carboxylase has been found only in several fungal species and green algae. in order to elucid ... | 2011 | 21447149 |
| [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 |
| the phytopathogen pseudomonas syringae pv. tomato dc3000 has three high-affinity iron-scavenging systems functional under iron limitation conditions but dispensable for pathogenesis. | high-affinity iron scavenging through the use of siderophores is a well-established virulence determinant in mammalian pathogenesis. however, few examples have been reported for plant pathogens. here, we use a genetic approach to investigate the role of siderophores in pseudomonas syringae pv. tomato dc3000 (dc3000) virulence in tomato. dc3000, an agronomically important pathogen, has two known siderophores for high-affinity iron scavenging, yersiniabactin and pyoverdin, and we uncover a third s ... | 2011 | 21441525 |
| 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 |
| [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 |
| negative regulation of immune responses on the fly. | 2011 | 21407251 | |
| antibacterial peptides from plants: what they are and how they probably work. | plant antibacterial peptides have been isolated from a wide variety of species. they consist of several protein groups with different features, such as the overall charge of the molecule, the content of disulphide bonds, and structural stability under environmental stress. although the three-dimensional structures of several classes of plant peptides are well determined, the mechanism of action of some of these molecules is still not well defined. however, further studies may provide new evidenc ... | 2011 | 21403856 |
| comparative genomics reveals diversity among xanthomonads infecting tomato and pepper. | bacterial spot of tomato and pepper is caused by four xanthomonas species and is a major plant disease in warm humid climates. the four species are distinct from each other based on physiological and molecular characteristics. the genome sequence of strain 85-10, a member of one of the species, xanthomonas euvesicatoria (xcv) has been previously reported. to determine the relationship of the four species at the genome level and to investigate the molecular basis of their virulence and differing ... | 2011 | 21396108 |
| lack of an antibacterial response defect in drosophila toll-9 mutant. | toll and toll-like receptors represent families of receptors involved in mediating innate immunity response in insects and mammals. although drosophila proteome contains multiple toll paralogs, toll-1 is, so far, the only receptor to which an immune role has been attributed. in contrast, every single mammalian tlr is a key membrane receptor upstream of the vertebrate immune signaling cascades. the prevailing view is that tlr-mediated immunity is ancient. structural analysis reveals that drosophi ... | 2011 | 21386906 |
| characterization of n-acylhomoserine lactone-degrading bacteria associated with the zingiber officinale (ginger) rhizosphere: co-existence of quorum quenching and quorum sensing in acinetobacter and burkholderia. | cell-to-cell communication (quorum sensing (qs)) co-ordinates bacterial behaviour at a population level. consequently the behaviour of a natural multi-species community is likely to depend at least in part on co-existing qs and quorum quenching (qq) activities. here we sought to discover novel n-acylhomoserine lactone (ahl)-dependent qs and qq strains by investigating a bacterial community associated with the rhizosphere of ginger (zingiber officinale) growing in the malaysian rainforest. | 2011 | 21385437 |
| [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 |
| 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 |
| drosophila immunity: analysis of pgrp-sb1 expression, enzymatic activity and function. | peptidoglycan is an essential and specific component of the bacterial cell wall and therefore is an ideal recognition signature for the immune system. peptidoglycan recognition proteins (pgrps) are conserved from insects to mammals and able to bind pgn (non-catalytic pgrps) and, in some cases, to efficiently degrade it (catalytic pgrps). in drosophila, several non-catalytic pgrps function as selective peptidoglycan receptors upstream of the toll and imd pathways, the two major signalling cascade ... | 2011 | 21364998 |
| engineering and visualization of bacteria for targeting infarcted myocardium. | optimization of the specific affinity of cardiac delivery vector could significantly improve the efficiency of gene/protein delivery, yet no cardiac vectors to date have sufficient target specificity for myocardial infarction (mi). in this study, we explored bacterial tropism for infarcted myocardium based on our previous observations that certain bacteria are capable of targeting the hypoxic regions in solid tumors. out of several escherichia coli or salmonella typhimurium strains, the s. typhi ... | 2011 | 21364539 |
| novel carbon-carbon bond formations for biocatalysis. | carbon-carbon bond formation is the key transformation in organic synthesis to set up the carbon backbone of organic molecules. however, only a limited number of enzymatic c-c bond forming reactions have been applied in biocatalytic organic synthesis. recently, further name reactions have been accomplished for the first time employing enzymes on a preparative scale, for instance the stetter and pictet-spengler reaction or oxidative c-c bond formation. furthermore, novel enzymatic c-c bond formin ... | 2011 | 21354781 |
| detection of acyl-homoserine lactones by escherichia and salmonella. | escherichia and salmonella do not synthesize quorum-sensing signaling molecules of the n-acyl-l-homoserine lactone (ahl) type but they can detect ahls produced by other species of bacteria. ahls are present in the bovine rumen but not in the remainder of the gastrointestinal tract. enterohemorrhagic e. coli (ehec) responds to ahls extracted from the bovine rumen. salmonella fails to detect ahls in the gastrointestinal tracts of pathogen-free mice or pigs, suggesting that ahls are not present. ho ... | 2011 | 21353625 |
| 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 |
| efficient production of soluble recombinant single chain fv fragments by a pseudomonas putida strain kt2440 cell factory. | recombinant antibody fragments have a wide range of applications in research, diagnostics and therapy. for many of these, small fragments like single chain fragment variables (scfv) function well and can be produced inexpensively in bacterial expression systems. although escherichia coli k-12 production systems are convenient, yields of different fragments, even those produced from codon-optimized expression systems, vary significantly. where yields are inadequate, alternative production systems ... | 2011 | 21338491 |
| glyceollin, a soybean phytoalexin with medicinal properties. | this review covers the biosynthesis of glyceollin and its biological activities including antiproliferative/antitumor action (toward b16 melanoma cells, lncap prostate cancer cells, and bg-1 ovarian cancer cells), anti-estrogenic action (through estrogen receptors a- and ß-), antibacterial action (toward erwinia carotovora, escherichia coli, bradyrhizobium japonicum, sinorhizobium fredii ), antinematode activity, and antifungal activity (toward fusarium solani, phakospora pachyrhizi, diaporthe p ... | 2011 | 21336922 |
| a udp-hexnac:polyprenol-p galnac-1-p transferase (wecp) representing a new subgroup of the enzyme family. | the aeromonas hydrophila ah-3 wecp represents a new class of udp-hexnac:polyprenol-p hexnac-1-p transferases. these enzymes use a membrane-associated polyprenol phosphate acceptor (undecaprenyl phosphate [und-p]) and a cytoplasmic udp-d-n-acetylhexosamine sugar nucleotide as the donor substrate. until now, all the weca enzymes tested were able to transfer udp-glcnac to the und-p. in this study, we present in vitro and in vivo proofs that a. hydrophila ah-3 wecp transfers galnac to und-p and is u ... | 2011 | 21335454 |
| recombinant bacteriophage lysins as antibacterials. | with the increasing worldwide prevalence of antibiotic resistant bacteria, bacteriophage endolysins (lysins) represent a very promising novel alternative class of antibacterial in the fight against infectious disease. lysins are phage-encoded peptidoglycan hydrolases which, when applied exogenously (as purified recombinant proteins) to gram-positive bacteria, bring about rapid lysis and death of the bacterial cell. a number of studies have recently demonstrated the strong potential of these enzy ... | 2010 | 21327123 |
| 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 |
| genetic diversity of o-antigen biosynthesis regions in vibrio cholerae. | o-antigen biosynthetic (wbf) regions for vibrio cholerae serogroups o5, o8, and o108 were isolated and sequenced. sequences were compared to those of other published v. cholerae o-antigen regions. these wbf regions showed a high degree of heterogeneity both in gene content and in gene order. genes identified frequently showed greater similarities to polysaccharide biosynthesis genes from species other than v. cholerae. our results demonstrate the plasticity of o-antigen genes in v. cholerae, the ... | 2011 | 21317260 |
| inhibition of predation by bdellovibrio bacteriovorus and micavibrio aeruginosavorus via host cell metabolic activity in the presence of carbohydrates. | bdellovibrio bacteriovorus and micavibrio aeruginosavorus are highly motile gram-negative predatory bacteria with the potential of being used as biocontrol agents or living antibiotics. it was suggested previously that sugar-binding proteins play a role in m. aeruginosavorus and b. bacteriovorus host specificity and predator-prey interactions. the effect of carbohydrates on predation was reexamined in this study. it was demonstrated that the presence of carbohydrates could indeed block predation ... | 2011 | 21317250 |
| 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 |
| a novel immunity system for bacterial nucleic acid degrading toxins and its recruitment in various eukaryotic and dna viral systems. | the use of nucleases as toxins for defense, offense or addiction of selfish elements is widely encountered across all life forms. using sensitive sequence profile analysis methods, we characterize a novel superfamily (the sukh superfamily) that unites a diverse group of proteins including smi1/knr4, pgs2, fbxo3, skip16, syd, herpesviral us22, irs1 and trs1, and their bacterial homologs. using contextual analysis we present evidence that the bacterial members of this superfamily are potential imm ... | 2011 | 21306995 |
| systematic biochemical analysis of somatic missense mutations in dna polymerase β found in prostate cancer reveal alteration of enzymatic function. | dna polymerase β is essential for short-patch base excision repair. we have previously identified 20 somatic pol β mutations in prostate tumors, many of them missense. in the current article we describe the effect of all of these somatic missense pol β mutations (p.k27n, p.e123k, p.e232k, p.p242r, p.e216k, p.m236l, and the triple mutant p.p261l/t292a/i298t) on the biochemical properties of the polymerase in vitro, following bacterial expression and purification of the respective enzymatic varian ... | 2011 | 21305655 |
| structural basis for c-di-gmp-mediated inside-out signaling controlling periplasmic proteolysis. | the bacterial second messenger bis-(3'-5') cyclic dimeric guanosine monophosphate (c-di-gmp) has emerged as a central regulator for biofilm formation. increased cellular c-di-gmp levels lead to stable cell attachment, which in pseudomonas fluorescens requires the transmembrane receptor lapd. lapd exhibits a conserved and widely used modular architecture containing a hamp domain and degenerate diguanylate cyclase and phosphodiesterase domains. c-di-gmp binding to the lapd degenerate phosphodieste ... | 2011 | 21304926 |
| a c-di-gmp effector system controls cell adhesion by inside-out signaling and surface protein cleavage. | in pseudomonas fluorescens pf0-1 the availability of inorganic phosphate (pi) is an environmental signal that controls biofilm formation through a cyclic dimeric gmp (c-di-gmp) signaling pathway. in low pi conditions, a c-di-gmp phosphodiesterase (pde) rapa is expressed, depleting cellular c-di-gmp and causing the loss of a critical outer-membrane adhesin lapa from the cell surface. this response involves an inner membrane protein lapd, which binds c-di-gmp in the cytoplasm and exerts a periplas ... | 2011 | 21304920 |
| 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 |
| stress resistance and longevity are not directly linked to levels of enzymatic antioxidants in the ponerine ant harpegnathos saltator. | the molecular mechanisms of variations in individual longevity are not well understood, even though longevity can be increased substantially by means of diverse experimental manipulations. one of the factors supposed to be involved in the increase of longevity is a higher stress resistance. to test this hypothesis in a natural system, eusocial insects such as bees or ants are ideally suited. in contrast to most other eusocial insects, ponerine ants show a peculiar life history that comprises the ... | 2011 | 21298046 |
| enteric bacteria and cancer stem cells. | intestinal bacteria can contribute to cell proliferation and cancer development, particularly in chronic infectious diseases in which bacteria and/or bacterial components might interfere with cell function. the number of microbial cells within the gut lumen is estimated to be 100 trillion, which is about 10-times larger than the number of eukaryotic cells in the human body. because of the complexity of the gut flora, identifying the specific microbial agents related to human diseases remains cha ... | 2010 | 21297903 |
| of pamps and effectors: the blurred pti-eti dichotomy. | typically, pathogen-associated molecular patterns (pamps) are considered to be conserved throughout classes of microbes and to contribute to general microbial fitness, whereas effectors are species, race, or strain specific and contribute to pathogen virulence. both types of molecule can trigger plant immunity, designated pamp-triggered and effector-triggered immunity (pti and eti, respectively). however, not all microbial defense activators conform to the common distinction between pamps and ef ... | 2011 | 21278123 |
| mutational analysis of the thienamycin biosynthetic gene cluster from streptomyces cattleya. | the generation of non-thienamycin-producing mutants with mutations in the thnl, thnn, thno, and thni genes within the thn gene cluster from streptomyces cattleya and their involvement in thienamycin biosynthesis and regulation were previously reported. four additional mutations were independently generated in the thnp, thng, thnr, and thnt genes by insertional inactivation. only the first two genes were found to play a role in thienamycin biosynthesis, since these mutations negatively or positiv ... | 2011 | 21263049 |
| hypersensitive response and acyl-homoserine lactone production of the fire blight antagonists erwinia tasmaniensis and erwinia billingiae. | fire blight caused by the gram-negative bacterium erwinia amylovora can be controlled by antagonistic microorganisms. we characterized epiphytic bacteria isolated from healthy apple and pear trees in australia, named erwinia tasmaniensis, and the epiphytic bacterium erwinia billingiae from england for physiological properties, interaction with plants and interference with growth of e. amylovora. they reduced symptom formation by the fire blight pathogen on immature pears and the colonization of ... | 2008 | 21261861 |
| quorum sensing and c-di-gmp-dependent alterations in gene transcripts and virulence-associated phenotypes in a clinical isolate of aeromonas hydrophila. | recently, we demonstrated that the luxs-based quorum sensing (qs) system (ai-2) negatively regulated the virulence of a diarrheal isolate ssu of aeromonas hydrophila, while the ahyri-based (ai-1) n-acyl-homoserine lactone system was a positive regulator of bacterial virulence. thus, these qs systems had opposing effects on modulating biofilm formation and bacterial motility in vitro models and in vivo virulence in a speticemic mouse model of infection. in this study, we linked these two qs syste ... | 2011 | 21256953 |
| developing microbe-plant interactions for applications in plant-growth promotion and disease control, production of useful compounds, remediation and carbon sequestration. | interactions between plants and microbes are an integral part of our terrestrial ecosystem. microbe-plant interactions are being applied in many areas. in this review, we present recent reports of applications in the areas of plant-growth promotion, biocontrol, bioactive compound and biomaterial production, remediation and carbon sequestration. challenges, limitations and future outlook for each field are discussed. | 2009 | 21255275 |
| genomics of plant-associated microbes. | 2009 | 21255272 | |
| saturation mutagenesis of a cepr binding site as a means to identify new quorum-regulated promoters in burkholderia cenocepacia. | burkholderia cenocepacia is an opportunistic pathogen of humans that encodes two genes that resemble the acylhomoserine lactone synthase gene luxi of vibrio fischeri and three genes that resemble the acylhomoserine lactone receptor gene luxr. of these, cepi synthesizes octanoylhomoserine lactone (ohl), while cepr is an ohl-dependent transcription factor. in the current study we developed a strategy to identify genes that are directly regulated by cepr. we systematically altered a cepr binding si ... | 2011 | 21255107 |
| biofilm development on caenorhabditis elegans by yersinia is facilitated by quorum sensing-dependent repression of type iii secretion. | yersinia pseudotuberculosis forms biofilms on caenorhabditis elegans which block nematode feeding. this genetically amenable host-pathogen model has important implications for biofilm development on living, motile surfaces. here we show that y. pseudotuberculosis biofilm development on c. elegans is governed by n-acylhomoserine lactone (ahl)-mediated quorum sensing (qs) since (i) ahls are produced in nematode associated biofilms and (ii) y. pseudotuberculosis strains expressing an ahl-degrading ... | 2011 | 21253572 |
| the small rna sgrs controls sugar-phosphate accumulation by regulating multiple pts genes. | a number of bacterial small rnas (srnas) act as global regulators of stress responses by controlling expression of multiple genes. the srna sgrs is expressed in response to glucose-phosphate stress, a condition associated with disruption of glycolytic flux and accumulation of sugar-phosphates. sgrs has been shown to stimulate degradation of the ptsg mrna, encoding the major glucose transporter. this study demonstrates that sgrs regulates the genes encoding the mannose and secondary glucose trans ... | 2011 | 21245045 |
| gi-type t4ss-mediated horizontal transfer of the 89k pathogenicity island in epidemic streptococcus suis serotype 2. | pathogenicity islands (pais), a distinct type of genomic island (gi), play important roles in the rapid adaptation and increased virulence of pathogens. 89k is a newly identified pai in epidemic streptococcus suis isolates that are related to the two recent large-scale outbreaks of human infection in china. however, its mechanism of evolution and contribution to the epidemic spread of s. suis 2 remain unknown. in this study, the potential for mobilization of 89k was evaluated, and its putative t ... | 2011 | 21244532 |