Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
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| the genome of non-o1 vibrio cholerae nrt36s demonstrates the presence of pathogenic mechanisms that are distinct from those of o1 vibrio cholerae. | vibrio cholerae nrt36s is a non-cholera toxin-producing, non-o1 strain that causes diarrhea in volunteers. the genome of nrt36s was sequenced to create a draft containing 174 contigs plus the superintegron region. our analysis of the draft genome revealed several putative toxin genes and colonization factors. besides confirming the existence of nonagglutinable heat-stable toxin, we also identified the genes for a type three secretion system, a putative exotoxin, two different rtx toxins, and fou ... | 2007 | 17283087 |
| virstatin inhibits dimerization of the transcriptional activator toxt. | the development of antimicrobials is critical in this time of increasing antibiotic resistance of most clinically relevant bacteria. to date, all current antibiotics focus on inhibiting crucial enzymatic activities of their protein targets (i.e., trimethoprim for dihydrofolate reductase), thus disrupting in vitro essential gene functions. in contrast, we have previously reported the identification of virstatin, a small molecule that inhibits virulence regulation in vibrio cholerae, thereby preve ... | 2007 | 17283330 |
| [classification and identification of vibrio cholerae and vibrio parahaemolyticus isolates based on gyrb gene phylogenetic analysis]. | in order to validate the usefulness of gyrb genotype for the classification and identification of vibrio cholerae and vibrio parahaemolyticus isolates, the phylogenetic analysis of 13 v. cholerae, 8 v. parahaemolyticus, 2 aeromonas hydrophila and 1 plesiomonas shigelloides strains was carried out using the partial coding sequence of gyrb, a gene that encodes the b subunit of dna gyrase (topoisomerase type ii ) in bacteria. these strains were separately clustered at species level and typed by the ... | 2006 | 17302148 |
| evaluation of phytotoxic elements, trace elements and nutrients in a standardized crop plant, irrigated with raw wastewater treated by apt and ozone. | this project studied the benefits of applying advanced primary treatment (apt) and ozone (o3) to raw wastewater destined for reuse in agriculture. the ozone was applied directly to raw wastewater, as well as to wastewater already treated with apt, and the results compared against a control sample of potable water. the experimental conditions that reported the best results was wastewater treated with o3 (at a dose of 4.8 mg/l, at ph 7, temperature 23 degrees c, for 1 hr), given that it met standa ... | 2006 | 17302317 |
| pore formation by vibrio cholerae cytolysin requires cholesterol in both monolayers of the target membrane. | vibrio cholerae cytolysin (vcc) forms oligomeric transmembrane pores in cholesterol-rich membranes. to better understand this process, we used planar bilayer membranes. in symmetric membranes, the rate of the channel formation by vcc has a superlinear dependency on the cholesterol membrane fraction. thus, more than one cholesterol molecule can facilitate vcc-pore formation. in asymmetric membranes, the rate of pore formation is limited by the leaflet with the lower cholesterol content. methyl-be ... | 2007 | 17303303 |
| pilz domain proteins bind cyclic diguanylate and regulate diverse processes in vibrio cholerae. | cyclic diguanylate (c-di-gmp) is an allosteric activator and second messenger implicated in the regulation of a variety of biological processes in diverse bacteria. in vibrio cholerae, c-di-gmp has been shown to inversely regulate biofilm-specific and virulence gene expression, suggesting that c-di-gmp signaling is important for the transition of v. cholerae from the environment to the host. however, the mechanism behind this regulation remains unknown. recently, it was proposed that the pilz pr ... | 2007 | 17307739 |
| broad up-regulation of innate defense factors during acute cholera. | we used a whole-genome microarray screening system (affymetrix human genechips covering 47,000 different transcripts) to examine the gene expression in duodenal mucosa during acute cholera. biopsies were taken from the duodenal mucosa of seven cholera patients 2 and 30 days after the onset of diarrhea, and the gene expression patterns in the acute- and convalescent-phase samples were compared pairwise. of about 21,000 transcripts expressed in the intestinal epithelium, 29 were defined as transcr ... | 2007 | 17307946 |
| suitability of partial 16s ribosomal rna gene sequence analysis for the identification of dangerous bacterial pathogens. | in a bioterrorism event a rapid tool is needed to identify relevant dangerous bacteria. the aim of the study was to assess the usefulness of partial 16s rrna gene sequence analysis and the suitability of diverse databases for identifying dangerous bacterial pathogens. | 2007 | 17309636 |
| antibacterial, antisecretory and antihemorrhagic activity of azadirachta indica used to treat cholera and diarrhea in india. | indigenous uses of azadirachta indica a. juss (maliaceae) (locally known as neem) leaves in different parts of india for curing gastrointestinal disorder such as diarrhea and cholera is wide spread. the objective of the present study was to evaluate the antibacterial and antisecretory activity of neem extract against vibrio cholerae, a causative agent of watery diarrhea such as cholera. the methanol extract of neem leaf was tested for its antibacterial, antisecretory and antihemorrhagic activity ... | 2007 | 17314018 |
| multiplex pcr for detection of antibiotic resistance genes and the sxt element: application in the characterization of vibrio cholerae. | this study describes a multiplex pcr assay for the detection of antibiotic resistance genes and the sxt element in vibrio cholerae. conditions were optimized to amplify fragments of sulii (encoding sulfamethoxazole resistance), dfra1 (o1-specific trimethoprim resistance), dfr18 (o139-specific trimethoprim resistance), strb (streptomycin b resistance) and the sxt element simultaneously in one pcr. this multiplex pcr was evaluated on 142 v. cholerae isolates and the results correlated with the phe ... | 2007 | 17314365 |
| resonance raman spectroscopic investigation of the light-harvesting chromophore in escherichia coli photolyase and vibrio cholerae cryptochrome-1. | photolyases and cryptochromes are flavoproteins that belong to the class of blue-light photoreceptors. they usually bind two chromophores: flavin adenine dinucleotide (fad), which forms the active site, and a light-harvesting pigment, which is a 5,10-methenyltetrahydrofolate polyglutamate (mthf) in most cases. in escherichia coli photolyase (ecphr), the mthf cofactor is present in substoichiometric amounts after purification, while in vibrio cholerae cryptochrome-1 (vccry1) the mthf cofactor is ... | 2007 | 17316023 |
| cholera vaccines. | 2007 | 17317594 | |
| identification of residues critical for the function of the vibrio cholerae virulence regulator toxt by scanning alanine mutagenesis. | virulence factor expression in vibrio cholerae is controlled by the transcriptional regulatory protein toxt. toxt activates transcription of the genes encoding cholera toxin (ctx) and the toxin co-regulated pilus (tcp), as well as accessory colonization factor (acf) genes. previous studies of toxt, a member of the arac family of proteins, have revealed that it consists of two domains, an n-terminal dimerization and environmental sensing domain, and a c-terminal dna binding domain. in this study, ... | 2007 | 17320105 |
| o3:k6 serotype of vibrio parahaemolyticus identical to the global pandemic clone associated with diarrhea in peru. | to determine if the vibrio parahaemolyticus o3:k6 global pandemic clone has spread into peru. | 2007 | 17321179 |
| quinone reduction by the na+-translocating nadh dehydrogenase promotes extracellular superoxide production in vibrio cholerae. | the pathogenicity of vibrio cholerae is influenced by sodium ions which are actively extruded from the cell by the na(+)-translocating nadh:quinone oxidoreductase (na(+)-nqr). to study the function of the na(+)-nqr in the respiratory chain of v. cholerae, we examined the formation of organic radicals and superoxide in a wild-type strain and a mutant strain lacking the na(+)-nqr. upon reduction with nadh, an organic radical was detected in native membranes by electron paramagnetic resonance spect ... | 2007 | 17322313 |
| medico - historical study of "visŭcikă" (cholera). | the sanskrit word visŭcikă refers to a condition in which vitiated văta dŏşa causes pain like pricking with a needle over the body. it occurs in a person suffering with ajĭrna (indigestion) and its detailed description is available in ayurvedic literature. this disease has its existence in india since ancient times; it has also been referred in mahăhărata and tripitikas. its etiology, signs, symptoms, complications, prognosis and treatment etc. as described in ayurveda may be correlated with the ... | 2005 | 17333658 |
| enteropathogenic bacteria and enterotoxin-producing staphylococcus aureus isolated from ready-to-eat foods in khon kaen, thailand. | the objective of this study was to investigate the microbiological quality of ready-to-eat food in the municipality of khon kaen, thailand. four categories of 186 food samples were collected: (1) high heat food; (2) low heat food; (3) no heat food; and, 4) on-site prepared fruit juices and beverages. of the food samples, 145 (78%) failed to meet acceptable microbiological standards, including fruit juice and beverages (100%), no heat food (91.7%), low heat food (81.7%) and high heat food (57.9%) ... | 2006 | 17333744 |
| [cholera]. | cholera is an acute intestinal infection that has reached pandemic proportions and presents a major international health concern. every year, more than 100000 cholera cases and 2000-3000 deaths are officially reported to who. the real figures for cholera are thought to be much higher, however, due to underreporting and other limitations of surveillance systems. cholera is caused by two serogroups (o1 and o139) of a gram-negative bacterium, vibrio cholerae. cholera toxins cause a massive outpouri ... | 2007 | 17336031 |
| expression level of heterologous tat genes is crucial for in vivo reconstitution of a functional tat translocase in escherichia coli. | the tat system has the remarkable capacity of exporting proteins in folded conformation across the cytoplasmic membrane. the functional tat translocase from gram-negative bacteria consists of tata, tatb and tatc proteins. to gain information about the species specificity of the tat translocase, we cloned tat genes from gram-negative pathogens shigella flexneri 2a str. 301, vibrio cholerae el tor n16961, pseudomonas aeruginosa pao1, thermophilic sulfolobus solfataricus p2, thermus thermophilus hb ... | 2007 | 17336443 |
| affinity of galectin-8 and its carbohydrate recognition domains for ligands in solution and at the cell surface. | galectin-8 has two different carbohydrate recognition domains (crds), the n-terminal gal-8n and the c-terminal gal-8c linked by a peptide, and has various effects on cell adhesion and signaling. to understand the mechanism for these effects further, we compared the binding activities of galectin-8 in solution with its binding and activation of cells. we used glycan array analysis to broaden the specificity profile of the two galectin-8 crds, as well as intact galectin-8s (short and long linker), ... | 2007 | 17339281 |
| prediction of epidemic cholera due to vibrio cholerae o1 in children younger than 10 years using climate data in bangladesh. | to determine if a prediction of epidemic cholera using climate data can be made, we performed autoregression analysis using the data recorded in dhaka city, bangladesh over a 20-year period (1983-2002) comparing the number of children aged <10 years who were infected with vibrio cholerae o1 to the maximum and minimum temperatures and rainfall. we formulated a simple autoregression model that predicts the monthly number of patients using earlier climate variables. the monthly number of patients p ... | 2008 | 17346360 |
| an extended toxr possyccat system for positive and negative selection of self-interacting transmembrane domains. | assay systems based on the toxr protein are widely used to investigate interaction of transmembrane domains that come from natural proteins or are isolated from combinatorial libraries. the principle of this method is that self-interaction of any given transmembrane domain, which is expressed within a toxr chimeric protein, drives toxr-toxr assembly in a bacterial inner membrane. in current versions of the system, toxr-toxr interaction drives transcription activation of the cholera toxin (ctx) p ... | 2007 | 17346832 |
| nonserogroup o1 vibrio cholerae in a renal transplant patient. | 2007 | 17353792 | |
| [a study of the prevalence of regulatory genes controlling virulence gene expression among vibrio choleraeeltor biovariant strains varying in their pandemic potential]. | the evolution of the genome of the pathogenic agent of the seventh cholera pandemia vibrio cholerae eltor biovariant was thought to occur by acquiring not only structural genes of virulence but also regulatory systems as a result of horizontal transfer events. the polymerase chain reaction revealed the presence of the following regulatory genes that control the virulence gene expression in the chromosome of pre-pandemic and pandemic strains of cholera vibrios eltor: toxr, toxt, tcpp, tcph, luxs, ... | 2007 | 17354604 |
| gene expression profile of vibrio cholerae in the cold stress-induced viable but non-culturable state. | vibrio cholerae is an aetiological agent of cholera that inhabits marine and estuarine environments. it can survive harsh environments by entering the viable but non-culturable (vbnc) state, but the related changes in gene expression have not been described. here, we experimentally induced the vbnc state in v. cholerae o1, by incubation in artificial seawater at 4 degrees c. bacterial cells that were incubated for 70 days retained their membrane integrity and were pathogenic, colonizing the gut ... | 2007 | 17359259 |
| genomic analysis of the mozambique strain of vibrio cholerae o1 reveals the origin of el tor strains carrying classical ctx prophage. | cholera outbreaks in subsaharan african countries are caused by strains of the el tor biotype of toxigenic vibrio cholerae o1. the el tor biotype is the causative agent of the current seventh cholera pandemic, whereas the classical biotype, which was associated with the sixth pandemic, is now extinct. besides other genetic differences the ctx prophages encoding cholera toxin in the two biotypes of v. cholerae o1 have distinct repressor (rstr) genes. however, recent incidences of cholera in mozam ... | 2007 | 17360342 |
| regulation of the stringent response is the essential function of the conserved bacterial g protein cgta in vibrio cholerae. | the gene encoding the conserved bacterial g protein cgta (obg) is essential for viability in every organism in which it has been studied. cgta has been reported to be involved in several diverse bacterial functions, including ribosome assembly, dna repair, sporulation, and morphological development. however, none of these functions have been identified as essential. here we show that depletion of cgta in vibrio cholerae causes global changes in gene expression that are consistent with induction ... | 2007 | 17360576 |
| the capsule polysaccharide structure and biogenesis for non-o1 vibrio cholerae nrt36s: genes are embedded in the lps region. | in v. cholerae, the biogenesis of capsule polysaccharide is poorly understood. the elucidation of capsule structure and biogenesis is critical to understanding the evolution of surface polysaccharide and the internal relationship between the capsule and lps in this species. v. cholerae serogroup o31 nrt36s, a human pathogen that produces a heat-stable enterotoxin (nag-st), is encapsulated. here, we report the covalent structure and studies of the biogenesis of the capsule in v. cholerae nrt36s. | 2007 | 17362509 |
| septicemia caused by a non-01 vibrio cholerae. | 1996 | 17372457 | |
| calorimetric assay for field detection of cholera. | 2007 | 17375388 | |
| changing serotypes and phage types of vibrio cholerae in ludhiana (punjab) during 2001-2005. | 2007 | 17377365 | |
| vibrio cholerae o1 strains are facultative intracellular bacteria, able to survive and multiply symbiotically inside the aquatic free-living amoeba acanthamoeba castellanii. | vibrio cholerae species are extracellular, waterborne, gram-negative bacteria that are overwhelmed by predators in aquatic environments. the unencapsulated serogroup v. cholerae o1 and encapsulated v. cholerae o139 cause epidemic and pandemic outbreaks of cholera. it has recently been shown that the aquatic and free-living amoeba acanthamoeba castellanii is not a predator to v. cholerae o139; rather, v. cholerae o139 has shown an intracellular compatibility with this host. the aim of this study ... | 2007 | 17381524 |
| small rnas controlling iron metabolism. | iron is one of the most important metals in the metabolism of many organisms, including bacteria, in which it serves as a cofactor in multiple enzymatic reactions. most of the earlier research on iron regulation in bacteria has focused on the transcriptional regulator fur and its effect on the many genes involved in iron uptake. more recent work demonstrates the essential role of a small regulatory rna, ryhb, in iron metabolism. ryhb downregulates a large number of transcripts encoding iron-usin ... | 2007 | 17383226 |
| wind direction and its linkage with vibrio cholerae dissemination. | the relevance of climatic events as causative factors for cholera epidemics is well known. however, examinations of the involvement of climatic factors in intracontinental disease distribution are still absent. | 2007 | 17384764 |
| growth response of vibrio cholerae and other vibrio spp. to cyanobacterial dissolved organic matter and temperature in brackish water. | environmental control of growth and persistence of vibrios in aquatic environments is poorly understood even though members of the genus vibrio are globally important pathogens. to study how algal-derived organic matter and temperature influenced the abundance of different vibrio spp., baltic sea microcosms inoculated with vibrio cholerae, vibrio vulnificus, vibrio parahaemolyticus, vibrio alginolyticus and native bacterioplankton, were exposed to different temperatures (12-25 degrees c) and ame ... | 2007 | 17386033 |
| the autophagic pathway: a cell survival strategy against the bacterial pore-forming toxin vibrio cholerae cytolysin. | vibrio cholerae is the causative agent of cholera in humans. in addition to the criticalvirulence factors cholera toxin and toxin coregulated pilus, v. cholerae secretes v.cholerae cytolysin (vcc), a pore-forming exotoxin able to induce cell lysis and extensivevacuolation. we have shown that this vacuolation is related to the activation of autophagyin response to vcc action. furthermore, we found that the autophagic pathway wasrequired to protect cells upon vcc intoxication. based on additional ... | 2007 | 17404497 |
| [examples for vaccines against diarrheal diseases--rotavirus and traveller's diarrhea]. | diarrheal diseases constitute one of the most important health problems worldwide. children less than 5 years, living in developing countries, are particularly in danger with respect to the incidence and severity of the gastrointestinal disorders. travelers to developing countries are also at risk to develop diarrheal disorders; around 30-50% of them acquire so called "travelers's diarrhea" caused by bacteria, viruses or protozoa. it has been estimated that approximately 30-70% of diarrhea are d ... | 2007 | 17427005 |
| a vibrio cholerae serogroup o1 vaccine candidate against ctx et phi infection. | cholera is a severe diarrheal disease that may spread rapidly. vaccination is considered a valid measure against it. we developed a new vaccine candidate, iem109, against vibrio cholerae. to generate this candidate, a chromosomal fragment containing the tlc element, attb of the ctx phi integration site, and rtx cluster responsible for the cytotoxic activity for mammalian cells was deleted through homologous recombination from the previously described el tor biotype, iem101. the protective genes ... | 2007 | 17428586 |
| expression of foreign proteins in a vibrio cholerae vaccine strain using the stationary phase hemagglutinin/protease promoter. | the use of the hemagglutinin(ha)/protease promoter and secretion signals to drive expression and secretion of a foreign antigen in a live genetically attenuated cholera vaccine candidate is demonstrated. a vibrio cholerae vaccine strain, containing a ha/protease-tetanus toxin c fragment (tcf) fusion, produced soluble-and cell-associated tcf. the fraction of tcf secreted to the culture medium was degraded unless expressed in a ha/protease-defective vaccine strain. comparison of the hapa promoter ... | 2007 | 17431549 |
| membrane association and multimerization of tcpt, the cognate atpase ortholog of the vibrio cholerae toxin-coregulated-pilus biogenesis apparatus. | the toxin-coregulated pilus (tcp) is one of the major virulence factors of vibrio cholerae. biogenesis of this type 4 pilus (tfp) requires a number of structural components encoded by the tcp operon. tcpt, the cognate putative atpase, is required for tcp biogenesis and all tcp-mediated functions. we studied the stability and localization of tcpt in cells containing in-frame deletions in each of the tcp genes. tcpt was detectable in each of the biogenesis mutants except the deltatcpt strain. tcpt ... | 2007 | 17434972 |
| quorum sensing enhances the stress response in vibrio cholerae. | vibrio cholerae lives in aquatic environments and causes cholera. here, we show that quorum sensing enhances v. cholerae viability under certain stress conditions by upregulating the expression of rpos, and this regulation acts through hapr, suggesting that a quorum-sensing-enhanced stress response plays a role in v. cholerae environmental survival. | 2007 | 17434996 |
| evidence for vertical inheritance and loss of the leukotoxin operon in genus mannheimia. | the mannheimia subclades belong to the same bacterial genus but have taken divergent paths toward their distinct lifestyles. m. haemolytica + m. glucosida are potential pathogens of the respiratory tract in the mammalian suborder ruminantia, whereas m. ruminalis, the supposed sister group, lives as a commensal in the ovine rumen. we have tested the hypothesis that horizontal gene transfer of the leukotoxin operon has catalyzed pathogenic adaptation and speciation of m. haemolytica + m. glucosida ... | 2007 | 17437147 |
| the hlyu protein is a positive regulator of rtxa1, a gene responsible for cytotoxicity and virulence in the human pathogen vibrio vulnificus. | vibrio vulnificus is an opportunistic human pathogen that preferentially infects compromised iron-overloaded patients, causing a fatal primary septicemia with very rapid progress, resulting in a high mortality rate. in this study we determined that the hlyu protein, a virulence factor in v. vulnificus cmcp6, up-regulates the expression of vv20479, a homologue of the vibrio cholerae rtx (repeats in toxin) toxin gene that we named rtxa1. this gene is part of an operon together with two other open ... | 2007 | 17438022 |
| sigma 28 promoter prediction in members of the gammaproteobacteria. | a two-step approach was used to predict sigma(28) promoter sequences in a number of gammaproteobacteria. putative promoters were initially identified upstream of motility and chemotaxis genes in test species based on their similarity to the escherichia coli sigma(28) promoter consensus. these sequences were then used to generate position specific score matrices that were used iteratively during whole-genome analyses. the consistent identification of promoter sequences upstream of orthologous gen ... | 2007 | 17439543 |
| small molecule inhibitors of a glycoside hydrolase attenuate inducible ampc-mediated beta-lactam resistance. | the increasing spread of plasmid-borne ampc-ampr operons is of considerable medical importance, since the ampc beta-lactamases they encode confer high level resistance to many third generation cephalosporins. induction of ampc beta-lactamase from endogenous or plasmid-borne ampc-ampr operons is mediated by a catabolic inducer molecule, 1,6-anhydro-n-acetylmuramic acid (murnac) tripeptide, an intermediate of the cell wall recycling pathway derived from the peptidoglycan. here we describe a strate ... | 2007 | 17439950 |
| biofilm acts as a microenvironment for plankton-associated vibrio cholerae in the aquatic environment of bangladesh. | the role of biofilm as a microenvironment of plankton-associated vibrio cholerae was investigated using plexiglass as a bait. a total of 72 biofilm samples were tested using culture, direct fluorescent antibody (dfa) and molecular techniques following standard procedures. culturable v. cholerae (smooth and rugose variants) were isolated from 33% of the samples. v. cholerae o1 were detected by fa technique throughout the year except april and june. all v. cholerae o1 isolates were positive for tc ... | 2007 | 17446676 |
| the potent antibacterial activity of sitafloxacin against fluoroquinolone-resistant clinical isolates of vibrio cholerae o1. | the in vitro antibacterial activity of sitafloxacin using clinical isolates of vibrio cholerae o1 was compared to other fluoroquinolones: ciprofloxacin, ofloxacin, sparfloxacin and levofloxacin. against fluoroquinolone-resistant o1 strains, sitafloxacin was 4- to 16-fold more effective than other fluoroquinolones at mic(90*). against fluoroquinolone-susceptible o1 strains, the mic(90) of sitafloxacin was 2- to 4-fold lower than other fluoroquinolones. this suggests sitafloxacin can be used in th ... | 2007 | 17446687 |
| detection and transformation of genome segments that differ within a coastal population of vibrio cholerae strains. | vibrio cholerae is an autochthonous member of diverse aquatic ecosystems around the globe. collectively, the genomes of environmental v. cholerae strains comprise a large repository of encoded functions which can be acquired by individual v. cholerae lineages through uptake and recombination. to characterize the genomic diversity of environmental v. cholerae, we used comparative genome hybridization to study 41 environmental strains isolated from diverse habitats along the central california coa ... | 2007 | 17449699 |
| genomic and phenotypic diversity of coastal vibrio cholerae strains is linked to environmental factors. | studies of vibrio cholerae diversity have focused primarily on pathogenic isolates of the o1 and o139 serotypes. however, autochthonous environmental isolates of this species routinely display more extensive genetic diversity than the primarily clonal pathogenic strains. in this study, genomic and metabolic profiles of 41 non-o1/o139 environmental isolates from central california coastal waters and four clinical strains are used to characterize the core genome and metabolome of v. cholerae. comp ... | 2007 | 17449702 |
| routine use of antimicrobial drugs during the 2004 cholera epidemic in douala, cameroon. | to evaluate routine use of antimicrobial drugs for treatment and prevention of cholera with special regards to the evolution of the antimicrobial drug resistance patterns of v. cholerae strains. | 2006 | 17455448 |
| [current status of multi-drug resistant bacteria in infectious diarrheal diseases and its control]. | 2007 | 17455674 | |
| specific detection of toxigenic vibrio cholerae based on in situ pcr in combination with flow cytometry. | to develop an in situ pcr in combination with flow cytometry (ispcr-fcm) for monitoring cholera toxin positive vibrio cholerae. | 2007 | 17458144 |
| use of chromosomal integron arrays as a phylogenetic typing system for vibrio cholerae pandemic strains. | approximately 200 serogroups of vibrio cholerae exist, with only two, o1 and o139, responsible for epidemic and pandemic cholera. strains from these serogroups have evolved from a common progenitor, with lateral gene transfer largely driving their emergence. these strains are so closely related that separation using single- or multi-locus phylogeny has proven difficult. v. cholerae strains contain a genetic system called the integron that is located in the chromosome and that can integrate and e ... | 2007 | 17464063 |
| autoprocessing of the vibrio cholerae rtx toxin by the cysteine protease domain. | vibrio cholerae rtx is a large multifunctional bacterial toxin that causes actin crosslinking. due to its size, it was predicted to undergo proteolytic cleavage during translocation into host cells to deliver activity domains to the cytosol. in this study, we identified a domain within the rtx toxin that is conserved in large clostridial glucosylating toxins tcdb, tcda, tcna, and tcsl; putative toxins from v. vulnificus, yersinia sp., photorhabdus sp., and xenorhabdus sp.; and a filamentous/hema ... | 2007 | 17464284 |
| genetic diversity of toxigenic and nontoxigenic vibrio cholerae serogroups o1 and o139 revealed by array-based comparative genomic hybridization. | toxigenic serogroups o1 and o139 of vibrio cholerae may cause cholera epidemics or pandemics. nontoxigenic strains within these serogroups also exist in the environment, and also some may cause sporadic cases of disease. herein, we investigate the genomic diversity among toxigenic and nontoxigenic o1 and o139 strains by comparative genomic microarray hybridization with the genome of el tor strain n16961 as a base. conservation of the toxigenic o1 el tor and o139 strains is found as previously re ... | 2007 | 17468246 |
| molecular dissection of the myelin-associated glycoprotein receptor complex reveals cell type-specific mechanisms for neurite outgrowth inhibition. | neuronal nogo66 receptor-1 (ngr1) binds the myelin inhibitors nogoa, omgp, and myelin-associated glycoprotein (mag) and has been proposed to function as the ligand-binding component of a receptor complex that also includes lingo-1, p75(ntr), or troy. in this study, we use vibrio cholerae neuraminidase (vcn) and mouse genetics to probe the molecular composition of the mag receptor complex in postnatal retinal ganglion cells (rgcs). we find that vcn treatment is not sufficient to release mag inhib ... | 2007 | 17470639 |
| antibacterial activity of ciprofloxacin against clinical strains of vibrio cholerae o139 recently isolated from india. | we determined the in vitro antibacterial activity of ciprofloxacin against vibrio cholerae o139 recently isolated from cholera patients in india. ciprofloxacin showed excellent antibacterial activity against the o139 strains, and ciprofloxacin-resistant o139 strains were not observed. the lack of incidence of ciprofloxacin resistance in o139 strains may be because o139 strains appeared comparatively recently and have not been extensively treated with antibacterial agents including fluoroquinolon ... | 2007 | 17473533 |
| inactivation of small rho gtpases by the multifunctional rtx toxin from vibrio cholerae. | many bacterial toxins target small rho gtpases in order to manipulate the actin cytoskeleton. the depolymerization of the actin cytoskeleton by the vibrio cholerae rtx toxin was previously identified to be due to the unique mechanism of covalent actin cross-linking. however, identification and subsequent deletion of the actin cross-linking domain within the rtx toxin revealed that this toxin has an additional cell rounding activity. in this study, we identified that the multifunctional rtx toxin ... | 2007 | 17474905 |
| genetic diversity of el tor strains of vibrio cholerae o1 with hybrid traits isolated from bangladesh and mozambique. | vibrio cholerae o1 strains that are hybrids between the classical and el tor biotypes were isolated during two consecutive years (2004-2005) from diarrheal patients in mozambique. similar variants isolated in bangladesh and recently isolated el tor strains were analyzed for genetic diversity. pulsed-field gel electrophoresis (pfge) analysis using the restriction enzyme noti, resulted in 18-21 bands showed five closely related pfge patterns that were distributed similarly in both years (2004-2005 ... | 2007 | 17475554 |
| identification and characterization of the vibrio vulnificus rtxa essential for cytotoxicity in vitro and virulence in mice. | a mutant exhibiting decreased cytotoxic activity toward int-407 intestinal epithelial cells and carrying a mutation in the rtx gene cluster that consists of rtxca and rtxbde operons was screened from a library of v. vulnificus mutants. the functions of the rtxa gene, assessed by constructing an isogenic mutant and evaluating its phenotypic changes, demonstrated that rtxa is essential for the virulence of v. vulnificus in mice as well as in tissue cultures. | 2007 | 17483800 |
| specificity in transmembrane helix-helix interactions mediated by aromatic residues. | aromatic residues have been previously shown to mediate the self-assembly of different soluble proteins through pi-pi interactions (mcgaughey, g. b., gagne, m., and rappe, a. k. (1998) j. biol. chem. 273, 15458-15463). however, their role in transmembrane (tm) assembly is not yet clear. in this study, we performed statistical analysis of the frequency of occurrence of aromatic pairs in a bacterial tm data base that provided an initial indication that the appearance of a specific aromatic pattern ... | 2007 | 17488729 |
| physicochemical characterization of el tor vibriophage s20. | to characterize vibrio cholerae el tor typing phage s20 (atcc no. 51352-b3). | 2007 | 17489024 |
| occurrence of vibrio cholerae serogroups other than o1 and o139 in austria. | from 2000 to 2005, 13 infections due to non-o1/non-o139 vibrio cholerae were documented in austria. twelve patients (8 years to 65 years old; 7 male) had symptomatic infections: diarrhea x 5, otitis x 6, septicemia once. all 5 patients who acquired their infections abroad, suffered from diarrhea. the 8 persons without travel history outside of austria had otitis media (n = 4) or otitis externa (n = 2); the lethal case of septicemia affected a fisherman with underlying malignancy. one isolate was ... | 2007 | 17492351 |
| vibrio cholerae strains possess multiple strategies for abiotic and biotic surface colonization. | despite its notoriety as a human pathogen, vibrio cholerae is an aquatic microbe suited to live in freshwater, estuarine, and marine environments where biofilm formation may provide a selective advantage. here we report characterization of biofilms formed on abiotic and biotic surfaces by two non-o1/o139 v. cholerae strains, tp and sio, and by the o1 v. cholerae strain n16961 in addition to the isolation of 44 transposon mutants of sio and tp impaired in biofilm formation. during the course of c ... | 2007 | 17496082 |
| distinct centromere-like pars sites on the two chromosomes of vibrio spp. | vibrio cholerae, the cause of cholera, has two circular chromosomes. the parab genes on each v. cholerae chromosome act to control chromosome segregation in a replicon-specific fashion. the chromosome i (chri) parab genes (parab1) govern the localization of the origin region of chri, while the chromosome ii (chrii) parab genes (parab2) control the segregation of chrii. in addition to para and parb proteins, par systems require parb binding sites (pars). here we identified the pars sites on both ... | 2007 | 17496089 |
| the quorum sensing regulator hapr downregulates the expression of the virulence gene transcription factor apha in vibrio cholerae by antagonizing lrp- and vpsr-mediated activation. | hapr is a quorum sensing-regulated transcription factor that represses the virulence cascade in vibrio cholerae by binding to a specific site centred at -71 in the apha promoter, ultimately preventing activation of the tcpph promoter on the vibrio pathogenicity island. in an effort to elucidate the mechanism by which hapr represses apha expression, we identified two transcriptional regulators, lrp and vpsr, both of which activate the apha promoter. lrp, the leucine-responsive regulatory protein, ... | 2007 | 17501920 |
| the rpry response regulator of porphyromonas gingivalis. | porphyromonas gingivalis is a gram-negative oral anaerobe associated with chronic adult periodontitis. its ecological niche is the gingival crevice, where the organism adapts to the challenges of the infectious process such as host defence and bacterial products. bacterial responses to environmental changes are partly regulated by two-component signal transduction systems. several intact systems were annotated in the genome of p. gingivalis, as well as an orphan regulator encoding a homologue of ... | 2007 | 17501928 |
| relationships between bacteroides 16s rrna genetic markers and presence of bacterial enteric pathogens and conventional fecal indicators. | occurrence and prevalence of different bacterial enteric pathogens as well as their relationships with conventional (total and fecal coliforms) and alternative fecal indicators (host-specific bacteroides 16s rrna genetic markers) were investigated for various water samples taken from different sites with different degrees of fecal contamination. the results showed that a wide range of bacterial pathogens could be detected in both municipal wastewater treatment plant samples and in surface water ... | 2007 | 17507075 |
| phenotypic and genotypic traits and epidemiological implication of vibrio cholerae o1 and o139 strains in india during 2003. | during 2003, vibrio cholerae o1 ogawa was the predominant serotype among diarrhoeal patients admitted to different hospitals in india. with the exception of 3 strains from kolkata, none of 172 strains examined exhibited resistance to tetracycline, but 45.7 % showed reduced susceptibility to ciprofloxacin. extensive molecular characterization using randomly amplified polymorphic dna analysis, ribotyping and pfge revealed that almost all the strains within a serogroup were clonally related. along ... | 2007 | 17510270 |
| comprehensive dna signature discovery and validation. | dna signatures are nucleotide sequences that can be used to detect the presence of an organism and to distinguish that organism from all other species. here we describe insignia, a new, comprehensive system for the rapid identification of signatures in the genomes of bacteria and viruses. with the availability of hundreds of complete bacterial and viral genome sequences, it is now possible to use computational methods to identify signature sequences in all of these species, and to use these sign ... | 2007 | 17511514 |
| antibacterial activity of quercus ilex bark's extracts. | the antibacterial activity of different extracts of quercus ilex bark (fagaceae) was studied in vitro against seven reference strains of bacteria by using a disc-diffusion method and agar-dilution method. the ethyl acetate extract (qe), n-butanol extract (qb) and final aqueous layer (qa) were effective against all bacterial strains tested at mics ranging from 128 to 512 microg/ml. the n-hexane extract (qh) and dichloromethane extract (qd) showed no activity. | 2007 | 17513077 |
| genetic characterization of vibrio cholerae strains by inter simple sequence repeat-pcr. | the utility of inter simple sequence repeat-pcr (issr-pcr) assay in the characterization and elucidation of the phylogenetic relationship between the pathogenic and nonpathogenic isolates of vibrio cholerae is demonstrated. a total of 45 v. cholerae strains including 15 o1 el tor, nine o139 and 21 non-o1/non-o139 strains were analyzed using eight issr primers. these primers, which are essentially simple sequence repeats (ssr) with additional nonrepeat bases at the 5' or 3' end, amplify genomic r ... | 2007 | 17521359 |
| rtx toxin actin cross-linking activity in clinical and environmental isolates of vibrio cholerae. | vibrio cholerae strains from diverse o-antigen groups were evaluated for rtx toxin actin cross-linking activity. this study demonstrates that the actin cross-linking domain sequence is present within rtxa in the majority of clinical and environmental isolates tested, and the rtx toxin produced by these strains catalyzes the covalent cross-linking of cellular actin. | 2007 | 17522276 |
| [cholera caused by vibrio cholerae o1 ctxab- tcpa+]. | results of analysis of cholera outbreak during which v. cholerae o1 biovar el-tor ctxab- tcpa+ was isolated from 2 patients and 30 carriers are presented. epidemic was caused by contamination of water source and water route of transmission. strains identical to ones detected in humans were isolated from water of surface well in zone of water intake. genome and vntr-analysis of ctxab- tcpa+ vibrios that caused outbreak in rostov region in 2005 showed that they differed from ctxab- tcpa- and ctxab ... | 2007 | 17523424 |
| [detection of lipase in vibrio cholerae serogroup o1 in reaction of volumetric agglomeration]. | study showed that el-tor strains of v. cholerae isolated from different sources produce lipase for hemolysis after cultivation during 24 h on meat-peptone broth independently from their toxigenic and hemolytic abilities. study of 3- and 4-hours broth cultures of vibrios revealed possibility to differentiate between hemolytic nontoxigenic strains and toxigenic nonhemolytic ones. using antilipaze diagnostic kit it was possible to differentiate el-tor vibrios from vibrios of classic biovar basing o ... | 2007 | 17523437 |
| crystal structure of the vibrio cholerae quorum-sensing regulatory protein hapr. | quorum sensing in vibrio cholerae involves signaling between two-component sensor protein kinases and the response regulator luxo to control the expression of the master regulator hapr. hapr, in turn, plays a central role in regulating a number of important processes, such as virulence gene expression and biofilm formation. we have determined the crystal structure of hapr to 2.2-a resolution. its structure reveals a dimeric, two-domain molecule with an all-helical structure that is strongly cons ... | 2007 | 17526705 |
| enhanced sensitivity to cholera toxin in adp-ribosylarginine hydrolase-deficient mice. | cholera toxin (ct) produced by vibrio cholerae causes the devastating diarrhea of cholera by catalyzing the adp-ribosylation of the alpha subunit of the intestinal gs protein (gsalpha), leading to characteristic water and electrolyte losses. mammalian cells contain adp-ribosyltransferases similar to ct and an adp-ribosyl(arginine)protein hydrolase (adprh), which cleaves the adp-ribose-(arginine)protein bond, regenerating native protein and completing an adp-ribosylation cycle. we hypothesized th ... | 2007 | 17526733 |
| emergence of vibrio cholerae o1 inaba in andaman & nicobar islands, india. | 2007 | 17545217 | |
| tight junction modulation and biochemical characterisation of the zonula occludens toxin c-and n-termini. | the zot n-terminal domain was expressed and refolded, yielding a soluble protein with defined secondary structure. although distantly related to protein i of filamentous phages, no evidence of atpase activity was found. it is therefore unlikely that the zot n-terminal domain is involved in cholera toxin phage packaging in vibrio cholerae. the zot c-terminal domain caused delocalisation of occludin and zo-1 from caco-2 cell-cell contacts, irrespective of disulfide bridge formation in its putative ... | 2007 | 17553496 |
| [isolation and identification of species from the genera aeromonas, vibrio, and plesiomonas from extraintestinal samples in cuba]. | extraintestinal infections caused by the genera aeromonas, vibrio and plesiomonas have high morbidity and mortality rates in different areas of world. from january 2002 to december 2003, the national reference laboratory for acute diarrhoeal diseases of the pedro kourí tropical medicine institute received 95 gram-negative, facultative anaerobic, oxidase positive bacilli strains from different extraintestinal specimen (blood, ear exudates, infected wounds, conjunctive exudates, urine, and cathete ... | 2007 | 17554439 |
| regulatory small rnas circumvent the conventional quorum sensing pathway in pandemic vibrio cholerae. | using a process called quorum sensing (qs), bacteria communicate with extracellular signal molecules called autoinducers (ais). response to ais allows bacteria to coordinate gene expression on a population-wide scale and thereby carry out particular behaviors in unison, much like multicellular organisms. in vibrio cholerae el tor, the etiological agent of the current cholera pandemic, ai information is transduced internally through a phosphorelay circuit that impinges on the transcription of mul ... | 2007 | 17556542 |
| the two chromosomes of vibrio cholerae are initiated at different time points in the cell cycle. | the bacterium vibrio cholerae, the cause of the diarrhoeal disease cholera, has its genome divided between two chromosomes, a feature uncommon for bacteria. the two chromosomes are of different sizes and different initiator molecules control their replication independently. using novel methods for analysing flow cytometry data and marker frequency analysis, we show that the small chromosome ii is replicated late in the c period of the cell cycle, where most of chromosome i has been replicated. o ... | 2007 | 17557077 |
| serogroup conversion of vibrio cholerae in aquatic reservoirs. | the environmental reservoirs for vibrio cholerae are natural aquatic habitats, where it colonizes the chitinous exoskeletons of copepod molts. growth of v. cholerae on a chitin surface induces competence for natural transformation, a mechanism for intra-species gene exchange. the antigenically diverse o-serogroup determinants of v. cholerae are encoded by a genetically variable biosynthetic cluster of genes that is flanked on either side by chromosomal regions that are conserved between differen ... | 2007 | 17559304 |
| invasive vibrio cholerae 01 e1 tor inaba in a 3-day-old neonate: case report. | a 3-day-old girl with invasive v. cholerae infection is described. her mother had cholera in the perinatal period. because of retracted nipples, she expressed milk and fed her infant by bottle. the infant died on the 2nd day of admission. | 2007 | 17565813 |
| vibrio cholerae hemolysin is apoptogenic to peritoneal b-1a cells but its oligomer shepherd the cells for iga response. | vibrio cholerae hemolysin (hlya) can exist as a monomer with hemolytic activity and an oligomer that agglutinates erythrocytes. biochemical differences accompanying the change in state of aggregation led us to weigh possible differences between the two forms from mucosal immunoregulation perspective. hlya oligomer-treated murine b-1a cells up-regulated tlr2 and involved the signaling molecules myd88, traf6 and nf-kappab. the cells subsequently expressed igm and iga. hlya monomer treatment althou ... | 2008 | 17570527 |
| single multiplex polymerase chain reaction for environmental surveillance of toxigenic-pathogenic o1 and non-o1 vibrio cholerae. | a multiplex pcr assay was developed for the detection of toxigenic and pathogenic v. cholerae from direct water sources using specific primers targeting diverse genes, viz. outer membrane protein (ompw), cholera toxin (ctxb), orf specific for o1 (rfbg), zonula occludens (zot) and toxin co-regulated pilus (tcpb); among these genes, ompw acts as internal control for v. cholerae, the ctx gene as a marker for toxigenicity and tcp for pathogenicity. the sensitivity of multiplex pcr was 5 x 10(4) v. c ... | 2007 | 17571801 |
| cholera among belgian travellers in turkey in 2005. | two elderly people among a group of eight belgian travellers who had stayed in turkey for 2 weeks, developed a severe enteritis shortly after their return to belgium. they had travelled by private bus, and had visited different places during their stay in turkey from 6 to 17 september 2005. | 2007 | 17574145 |
| [application of pulse-field gel electrophoresis analysis in the source-tracking of cholera epidemics]. | to apply pulse-field gel electrophoresis analysis(pfge) in the analysis of cholera outbreak events and to determine the molecular epidemiological characteristics of vibrio cholerae ( v. cholerae) isolates. | 2007 | 17575935 |
| differential expression of intestinal membrane transporters in cholera patients. | vibrio cholerae causes the cholera disease through secretion of cholera toxin (ct), resulting in severe diarrhoea by modulation of membrane transporters in the intestinal epithelium. genes encoding membrane-spanning transporters identified as being differentially expressed during cholera disease in a microarray screening were studied by real-time pcr, immunohistochemistry and in a caco-2 cell model. two amino acid transporters, slc7a11 and slc6a14, were upregulated in acute cholera patients comp ... | 2007 | 17575980 |
| catecholamine-induced stimulation of growth in vibrio species. | to evaluate the effect of norepinephrine (ne) and related compounds on the growth of bacteria, we have examined the effect of the neuroendocrine hormone ne and related compounds on the growth of vibrio parahaemolyticus and other human-pathogenic vibrio species (vibrio cholerae, vibrio vulnificus, and vibrio mimicus). | 2007 | 17576228 |
| retraction of "structure of msba from vibrio cholera: a multidrug resistance abc transporter homolog in a closed conformation" [j. mol. biol. (2003) 330 419-430]. | 2007 | 17580380 | |
| circulating phage type of vibrio cholerae in mumbai. | 2007 | 17582202 | |
| faecal contamination of drinking water sources of dhaka city during the 2004 flood in bangladesh and use of disinfectants for water treatment. | to describe the extent of faecal pollution and point of use water treatment strategy during and after the 2004 flood in dhaka. | 2007 | 17584454 |
| effect of environmental factors on expression and activity of chitinase genes of vibrios with special reference to vibrio cholerae. | the aim of this study was to investigate the distribution and inducibility of chitinase genes in vibrios and the effect of environmental factors on the expression level and activity of chitinase genes in vibrio cholerae strains. | 2007 | 17584456 |
| probing the flexibility of the dsba oxidoreductase from vibrio cholerae--a 15n - 1h heteronuclear nmr relaxation analysis of oxidized and reduced forms of dsba. | we have determined the structure of the reduced form of the dsba oxidoreductase from vibrio cholerae. the reduced structure shows a high level of similarity to the crystal structure of the oxidized form and is typical of this class of enzyme containing a thioredoxin domain with an inserted alpha-helical domain. proteolytic and thermal stability measurements show that the reduced form of dsba is considerably more stable than the oxidized form. nmr relaxation data have been collected and analyzed ... | 2007 | 17585933 |
| blood group antigen recognition by escherichia coli heat-labile enterotoxin. | in a number of bacterial infections, such as helicobacter pylori, campylobacter jejuni and vibrio cholerae infections, a correlation between the severity of disease and blood group phenotype of infected individuals has been observed. in the present investigation, we have studied the molecular basis of this effect for enterotoxigenic escherichia coli (etec) infections. etec are non-invasive bacteria, which act through second messenger pathways to cause diarrhea. it has been suggested that the maj ... | 2007 | 17586525 |
| expression of hurp, a gene encoding a prospective site 2 protease, is essential for heme-dependent induction of bhur in bordetella bronchiseptica. | expression of the hurir bhurstuv heme utilization locus in bordetella bronchiseptica is coordinately controlled by the global iron-dependent regulator fur and the extracytoplasmic function sigma factor huri. activation of huri requires transduction of a heme-dependent signal via huri, hurr, and bhur, a three-component heme-dependent regulatory system. in silico searches of the b. bronchiseptica genome to identify other genes that encode additional participants in this heme-dependent regulatory c ... | 2007 | 17586630 |
| identification and analysis of a highly conserved chemotaxis gene cluster in shewanella species. | a conserved cluster of chemotaxis genes was identified from the genome sequences of fifteen shewanella species. an in-frame deletion of the chea-3 gene, which is located in this cluster, was created in s. oneidensis mr-1 and the gene shown to be essential for chemotactic responses to anaerobic electron acceptors. the chea-3 protein showed strong similarity to vibrio cholerae chea-2 and p. aeruginosa chea-1, two proteins that are also essential for chemotaxis. the genes encoding these proteins we ... | 2007 | 17590227 |
| rnase e-dependent processing stabilizes micx, a vibrio cholerae srna. | in vibrio cholerae, bioinformatic approaches have been used to predict the locations of numerous small rna (srna)-encoding genes, but biological roles have been determined for very few. here, we describe the expression, processing and biological role of an srna (previously known as a10) that was identified through such analyses. we have renamed this srna micx as, like the escherichia coli srnas mica, micc and micf, it regulates expression of an outer membrane protein (omp). micx appears to be a ... | 2007 | 17590231 |
| human intestinal epithelial cell cytokine mrna responses mediated by nf-kappab are modulated by the motility and adhesion process of vibrio cholerae. | vibro cholerae, the etiological agent of cholera, colonizes the small intestine, produces an enterotoxin and causes acute inflammatory response at intestinal epithelial surface; the signals for such induction are still unknown. we determined the mrna expression of proinflammatory and anti-inflammatory cytokines in int407 cells following infection with v. cholerae or its mutants by semi-quantitaive and quantitative real-time rt-pcr. v. cholerae induces the coordinated expression and up-regulation ... | 2007 | 17590380 |