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multiple antibiotic resistance of vibrio cholerae serogroup o139 in china from 1993 to 2009.regarded as an emerging diarrheal micropathogen, vibrio cholerae serogroup o139 was first identified in 1992 and has become an important cause of cholera epidemics over the last two decades. o139 strains have been continually isolated since o139 cholera appeared in china in 1993, from sporadic cases and dispersed foodborne outbreaks, which are the common epidemic types of o139 cholera in china. antibiotic resistance profiles of these epidemic strains are required for development of clinical trea ...201222701685
in-house contamination of potable water in urban slum of kolkata, india: a possible transmission route of diarrhea.we have investigated and determined the potentiality of different water sources, both for drinking and domestic purposes, in diarrheal disease transmission in diarrhea endemic foci of urban slums in kolkata, india in a one and half year prospective study. out of 517 water samples, collected from different sources, stored water (washing) showed higher prevalence of fecal coliforms (58%) (p < 0.0001) in comparison with stored (drinking) samples (28%) and tap/tubewell water (8%) respectively. among ...201222699333
evolutionary perspective on the origin of haitian cholera outbreak strain.cholera epidemic has not been reported in haiti for at least 100 years, although cholera has been present in latin america since 1991. surprisingly, the recent cholera epidemic in haiti (october 2010) recorded more than 250,000 cases and 4000 deaths in the first 6 months and became one of the most explosive and deadly cholera outbreak in recent history. in the present study, we conducted genomic analyses of pathogenicity islands of three haitian vibrio cholerae strains and compared them with nin ...201222693991
[use of various methods to isolate exopolysaccharide of eltor cholera vibrios and its immunochemical characteristics].isolation of vibrio eltor exopolysaccharide and study of its immunochemical properties.201222693805
sequence analyses of type iv pili from vibrio cholerae, vibrio parahaemolyticus, and vibrio vulnificus.bacterial surface structures called pili have been studied extensively for their role as possible colonization factors. most sequenced vibrio genomes predict a variety of pili genes in these organisms, including several types of type iv pili. in particular, the mannose-sensitive hemagglutinin (msha) and the pila pili, also known as the chitin-regulated pilus (chirp), are type iva pili commonly found in vibrio genomes and have been shown to play a role in the colonization of vibrio species in the ...201222383120
characterization of vibrio cholerae o139 of an aquatic isolate in northern vietnam.during the cholera survey in namdinh province (northern vietnam) in july, 2010, one strain of vibrio cholerae o139 was isolated from 7 environmental water samples positive for ctxa, toxr,vco139 genes and named as v. cholerae o139, nd1 strain. this strain was lysogenic harbouring a genome similar to the filamentous phage fs1. the replicative form dna of this phage (named as nd1-fs1, 6856 bp) was sequenced and compared with the other filamentous phages. the filamentous phage nd1-fs1 integrates int ...201222371817
type vi secretion requires a dynamic contractile phage tail-like structure.type vi secretion systems are bacterial virulence-associated nanomachines composed of proteins that are evolutionarily related to components of bacteriophage tails. here we show that protein secretion by the type vi secretion system of vibrio cholerae requires the action of a dynamic intracellular tubular structure that is structurally and functionally homologous to contractile phage tail sheath. time-lapse fluorescence light microscopy reveals that sheaths of the type vi secretion system cycle ...201222367545
the single nqrb and nqrc subunits in the na(+)-translocating nadh: quinone oxidoreductase (na(+)-nqr) from vibrio cholerae each carry one covalently attached fmn.the na(+)-translocating nadh:quinone oxidoreductase (na(+)-nqr) is the prototype of a novel class of flavoproteins carrying a riboflavin phosphate bound to serine or threonine by a phosphodiester bond to the ribityl side chain. this membrane-bound, respiratory complex also contains one non-covalently bound fad, one non-covalently bound riboflavin, ubiquinone-8 and a [2fe-2s] cluster. here, we report the quantitative analysis of the full set of flavin cofactors in the na(+)-nqr and characterize t ...201222366169
a rapid and reliable species-specific identification of clinical and environmental isolates of vibrio cholerae using a three-test procedure and reca polymerase chain reaction.vibrio cholerae, the cause of cholera, is one of the leading causes of morbidity and mortality in many developing countries. most laboratories initially rely on biochemical tests for a presumptive identification of these strains, followed by a polymerase chain reaction (pcr)-based method to confirm their identification. the aim of this study is to establish a rapid and reliable identification scheme for v. cholerae using a minimal, but highly specific number of biochemical tests and a pcr assay.201222361759
development and evaluation of a pcr assay for tracking the emergence and dissemination of haitian variant ctxb in vibrio cholerae o1 strains isolated from kolkata, india.a pcr-based assay was developed to discriminate the classical, el tor, and haitian types of ctxb alleles. our retrospective study using this newly developed pcr showed that haitian ctxb first appeared in kolkata during april 2006, and 93.3% of strains isolated during 2011 carried the new allele. dendrogram analysis showed a pulsed-field gel electrophoresis (pfge) pattern of the new variant strains isolated recently that was distinct from the pfge pattern of the strains carrying classical ctxb th ...201222357499
the vibrio cholerae pst2 phosphate transport system is upregulated in biofilms and contributes to biofilm-induced hyperinfectivity.vibrio cholerae is the causative agent of the deadly diarrheal disease cholera. as part of its life cycle, v. cholerae persists in marine environments, where it forms surface-attached communities commonly described as biofilms. evidence indicates that these biofilms constitute the infectious form of the pathogen during outbreaks. previous work has shown that biofilm-derived v. cholerae cells, even when fully dispersed from the biofilm matrix, are vastly more infectious than planktonic (free-livi ...201222354023
clinical characteristics and predictors of positive stool culture in adult patients with acute gastroenteritis.to identify the presenting features and spectrum of pathogens in adult patients with acute diarrhoea and to determine the predictors of stool culture positivity.201222352095
[intracerebral abscess after infection with non-toxigenic vibrio cholerae].we present the first case of intracerebral abscess after blood-borne infection with non-toxigenic vibrio cholerae (non-01). the patient was a 66 year-old woman who was infected after swimming in danish seawater during an unusually hot summer. she had predisposing haemochromatosis and a skin lesion on the ankle. we treated the patient with meropenem and ciprofloxacin for six weeks followed by ciprofloxacin for four weeks, and she recovered with hemiparesis and speech impairment. marine vibrio spe ...201222348672
interleukin-8 gene regulation in epithelial cells by vibrio cholerae: role of multiple promoter elements, adherence and motility of bacteria and host mapks.interleukin (il)-8 is an important mediator in neutrophil-mediated acute inflammation. we previously demonstrated that incubation of intestinal epithelial cells with vibrio cholerae o395 resulted in increased il-8 mrna expression and il-8 secretion, which was associated with the adherence and motility of bacteria. however, the mechanisms responsible for transcriptional regulation of the il-8 gene in epithelial cells during v. cholerae infections were not explored. transient transfection analysis ...201222348317
sialic acid catabolism and transport gene clusters are lineage specific in vibrio vulnificus.sialic or nonulosonic acids are nine-carbon alpha ketosugars that are present in all vertebrate mucous membranes. among bacteria, the ability to catabolize sialic acid as a carbon source is present mainly in pathogenic and commensal species of animals. previously, it was shown that several vibrio species carry homologues of the genes required for sialic acid transport and catabolism, which are genetically linked. in vibrio cholerae on chromosome i, these genes are carried on the vibrio pathogeni ...201222344665
viability kinetics, induction, resuscitation and quantitative real-time polymerase chain reaction analyses of viable but nonculturable vibrio cholerae o1 in freshwater microcosm.to study the induction of a viable but nonculturable (vbnc) state in vibrio cholerae o1 in freshwater, in response to cold temperatures (4°c) and starvation.201222324483
transition state analysis of vibrio cholerae sialidase-catalyzed hydrolyses of natural substrate analogues.a series of isotopically labeled natural substrate analogues (phenyl 5-n-acetyl-α-d-neuraminyl-(2→3)-β-d-galactopyranosyl-(1→4)-1-thio-β-d-glucopyranoside; neu5acα2,3lacβsph, and the corresponding 2→6 isomer) were prepared chemoenzymatically in order to characterize, by use of multiple kinetic isotope effect (kie) measurements, the glycosylation transition states for vibrio cholerae sialidase-catalyzed hydrolysis reactions. the derived kies for neu5acα2,3lacβsph for the ring oxygen ((18)v/k), le ...201222296330
ligand and antagonist driven regulation of the vibrio cholerae quorum-sensing receptor cqss.quorum sensing, a bacterial cell-cell communication process, controls biofilm formation and virulence factor production in vibrio cholerae, a human pathogen that causes the disease cholera. the major v. cholerae autoinducer is (s)-3-hydroxytridecan-4-one (cai-1). a membrane bound two-component sensor histidine kinase called cqss detects cai-1, and the cqss → luxu → luxo phosphorelay cascade transduces the information encoded in cai-1 into the cell. because the cai-1 ligand is known and because t ...201222295878
genotypic and pfge/mlva analyses of vibrio cholerae o1: geographical spread and temporal changes during the 2007-2010 cholera outbreaks in thailand.vibrio cholerae o1 el tor dominated the seventh cholera pandemic which occurred in the 1960s. for two decades, variants of v. cholerae o1 el tor that produce classical cholera toxin have emerged and spread globally, replacing the prototypic el tor biotype. this study aims to characterize v. cholerae o1 isolates from outbreaks in thailand with special reference to genotypic variations over time.201222292065
connecting environment and genome plasticity in the characterization of transformation-induced sos regulation and carbon catabolite control of the vibrio cholerae integron integrase.the human pathogen vibrio cholerae carries a chromosomal superintegron (si). the si contains an array of hundreds of gene cassettes organized in tandem which are stable under conditions when no particular stress is applied to bacteria (such as during laboratory growth). rearrangements of these cassettes are catalyzed by the activity of the associated integron integrase. understanding the regulation of integrase expression is pivotal to fully comprehending the role played by this genetic reservoi ...201222287520
the histone-like nucleoid structuring protein (h-ns) is a repressor of vibrio cholerae exopolysaccharide biosynthesis (vps) genes.the capacity of vibrio cholerae to form biofilms has been shown to enhance its survival in the aquatic environment and play important roles in pathogenesis and disease transmission. in this study, we demonstrated that the histone-like nucleoid structuring protein is a repressor of exopolysaccharide (vps) biosynthesis genes and biofilm formation.201222287003
elevated levels of the norspermidine synthesis enzyme nspc enhance vibrio cholerae biofilm formation without affecting intracellular norspermidine concentrations.biofilm formation in vibrio cholerae is in part regulated by norspermidine, a polyamine synthesized by the enzyme carboxynorspermidine decarboxylase (nspc). the absence of norspermidine in the cell leads to a marked reduction in v. cholerae biofilm formation by an unknown mechanism. in this work, we show that overexpression of nspc results in large increases in biofilm formation and vps gene expression as well as a significant decrease in motility. interestingly, increased nspc levels do not lea ...201222239666
the "first" case of cholera in haiti: lessons for global health.cholera is an acute watery diarrheal disease caused by infection with vibrio cholerae. the disease has a high fatality rate when untreated and outbreaks of cholera have been increasing globally in the past decade, most recently in haiti. we present the case of a 28-year-old haitian male with a history of severe untreated mental health disorder that developed acute fatal watery diarrhea in mid-october 2010 in central haiti after drinking from the local river. we believe he is the first or among t ...201222232448
arctic actinomycetes as potential inhibitors of vibrio cholerae biofilm.the aim of this study was to identify novel biofilm inhibitors from actinomycetes isolated from the arctic against vibrio cholerae, the causative agent of cholera. the biofilm inhibitory activity of actinomycetes was assessed using biofilm assay and was confirmed using air-liquid interphase coverslip assay. the potential isolates were identified using 16s rrna gene sequencing. of all, three isolates showed significant biofilm inhibition against v. cholerae. the results showed that 20% of the act ...201222231452
wbet sequence typing and is1004 profiling of vibrio cholerae isolates.to investigate the molecular basis for serotype variation in vibrio cholerae o1 and the genetic relatedness amongst different serotypes isolated from 2004 to 2008 in iran.201222225492
real-time pcr and nasba for rapid and sensitive detection of vibrio cholerae in ballast water.transport of ballast water is one major factor in the transmission of aquatic organisms, including pathogenic bacteria. the imo-guidelines of the convention for the control and management of ships' ballast water and sediments, states that ships are to discharge <1 cfu per 100 ml ballast water of toxigenic vibrio cholerae, emphasizing the need to establish test methods. to our knowledge, there are no methods sensitive and rapid enough available for cholera surveillance of ballast water. in this s ...201222221710
use of rep- and eric-pcr to reveal genetic heterogeneity of vibrio cholerae from edible ice in jakarta, indonesia.vibrio cholerae is the causative organism of waterborne disease, cholera. v. cholerae has caused many epidemics and pandemics of cholera for many years. in this study, v. cholerae recovered from edible ice were investigated for their genetic diversity using enterobacterial repetitive intergenic consensus (eric) pcr and repetitive extragenic palindromic (rep) pcr. isolation was done using selective medium and the presumptive isolates were confirmed through biochemical and serological assays.201224576322
activation of cholera toxin production by anaerobic respiration of trimethylamine n-oxide in vibrio cholerae.vibrio cholerae is a gram-negative bacterium that causes cholera. although the pathogenesis caused by this deadly pathogen takes place in the intestine, commonly thought to be anaerobic, anaerobiosis-induced virulence regulations are not fully elucidated. anerobic growth of the v. cholerae strain, n16961, was promoted when trimethylamine n-oxide (tmao) was used as an alternative electron acceptor. strikingly, cholera toxin (ct) production was markedly induced during anaerobic tmao respiration. n ...201223019319
preventing maritime transfer of toxigenic vibrio cholerae.organisms, including vibrio cholerae, can be transferred between harbors in the ballast water of ships. zones in the caribbean region where distance from shore and water depth meet international maritime organization guidelines for ballast water exchange are extremely limited. use of ballast water treatment systems could mitigate the risk for organism transfer.201223017338
metr-regulated vibrio cholerae metabolism is required for virulence.lysr-type transcriptional regulators (lttrs) are the largest, most diverse family of prokaryotic transcription factors, with regulatory roles spanning metabolism, cell growth and division, and pathogenesis. using a sequence-defined transposon mutant library, we screened a panel of v. cholerae el tor mutants to identify lttrs required for host intestinal colonization. surprisingly, out of 38 lttrs, only one severely affected intestinal colonization in the suckling mouse model of cholera: the meth ...201223015737
the occurrence of pathogenic bacteria in some ships' ballast water incoming from various marine regions to the sea of marmara, turkey.the composition and frequency of antibiotic resistance of pathogenic bacteria, the abundance of heterotrophic aerobic bacteria (hpc) and possible in-situ use of chromogenic agar were investigated in the ships' ballast water coming from different regions of the world to the sea of marmara, turkey for the first time. the samples that were taken from 21 unit ships coming from various marine environments of the southern china sea, the atlantic ocean, the mediterranean and the black sea to the sea of ...201222998778
comparison of immune responses to the o-specific polysaccharide and lipopolysaccharide of vibrio cholerae o1 in bangladeshi adult patients with cholera.immunity against vibrio cholerae o1 is serogroup specific, and serogrouping is defined by the o-specific polysaccharide (osp) part of lipopolysaccharide (lps). despite this, human immune responses to v. cholerae osp have not previously been characterized. we assessed immune responses against v. cholerae osp in adults with cholera caused by v. cholerae o1 el tor serotype inaba or ogawa in dhaka, bangladesh, using o1 osp-core-bovine serum albumin (ospc:bsa) conjugates; responses targeted osp in th ...201222993410
structural insight into the isc domain of vibb from vibrio cholerae at atomic resolution: a snapshot just before the enzymatic reaction.the n-terminal isochorismatase (isc) domain of vibb (vibb-isc) catalyzes the vinyl ether hydrolysis of isochorismate to 2,3-dihydro-2,3-dihydroxybenzoate and pyruvate. structures of the isc domain and its complex with isochorismate have been determined at 1.35 and 1.10 å resolution, respectively. two catalytic waters which were absent from previously reported homologous structures were observed adjacent to isochorismate and the catalytic residues (asp35 and lys118) in the vibb-isc complex. molec ...201222993087
genetic characteristics of drug-resistant vibrio cholerae o1 causing endemic cholera in dhaka, 2006-2011.vibrio cholerae o1 biotype el tor (et), causing the seventh cholera pandemic, was recently replaced in bangladesh by an altered et possessing ctxb of the classical (cl) biotype, which caused the first six cholera pandemics. in the present study, v. cholerae o1 strains associated with endemic cholera in dhaka between 2006 and 2011 were analysed for major phenotypic and genetic characteristics. of 54 representative v. cholerae isolates tested, all were phenotypically et and showed uniform resistan ...201222977073
frequency of reexposure to vibrio cholerae o1 evaluated by subsequent vibriocidal titer rise after an episode of severe cholera in a highly endemic area in bangladesh.vibriocidal antibody is a marker of recent exposure to vibrio cholerae o1 infection. we examined vibriocidal titers for 1 year after an episode of severe cholera in patients in dhaka, bangladesh; 16 of 53 (30%) patients had a fourfold or greater increase in vibriocidal titer between 6 and 12 months after an episode of severe cholera, suggesting reexposure to the organism. among patients with rises in titers during follow-up, the patients initially infected with serotype ogawa had earlier rises i ...201222964723
high depth, whole-genome sequencing of cholera isolates from haiti and the dominican republic.whole-genome sequencing is an important tool for understanding microbial evolution and identifying the emergence of functionally important variants over the course of epidemics. in october 2010, a severe cholera epidemic began in haiti, with additional cases identified in the neighboring dominican republic. we used whole-genome approaches to sequence four vibrio cholerae isolates from haiti and the dominican republic and three additional v. cholerae isolates to a high depth of coverage (>2000x); ...201222963323
cholera outbreak in senegal in 2005: was climate a factor?cholera is an acute diarrheal illness caused by vibrio cholerae and occurs as widespread epidemics in africa. in 2005, there were 31,719 cholera cases, with 458 deaths in the republic of senegal. we retrospectively investigated the climate origin of the devastating floods in mid-august 2005, in the dakar region of senegal and the subsequent outbreak of cholera along with the pattern of cholera outbreaks in three other regions of that country. we compared rainfall patterns between 2002 and 2005 a ...201222952995
investigation of real-time photorepair activity on dna via surface plasmon resonance.the cyclobutane pyrimidine dimer (cpd) and 6-4 lesion formations along with the specific breaks on strands are the most common type of dna damage caused by ultraviolet light (uv) irradiation. cpd photolyase i and ii construct two subfamilies of flavoproteins, which have recognition and repair capabilities of cpd sites on both single stranded (ssdna) and double stranded dna (dsdna) with the aid of blue light energy. the other types of flavoprotein family consist of cryptochromes (cry) that act as ...201222952969
immune-stimulating potential of cell envelope proteins from vibrio cholerae associated to chitosan microparticles: an in vitro study.cholera is a severe diarrheal disease that remains an important cause of illness and death in many parts of the world.201222947068
[molecular-genetic analysis of the epidemical strains of the vibrio cholerae el tor isolated from the siberian and maritime regions of russia].the detection of the biotype-specificity, pathogenicity determinants, and sequencing of the ctxb gene and the ctxab promoter was carried out for analysis of the vibrio cholerae el tor strains genome structure. the strains (n = 90) were isolated during cholera epidemic outbreaks in siberia and the far east. all toxigenic vibrio cholerae el tor strains were divided into two groups: the first group included strains isolated during 1970s: they had the genotype ctxb3+rstrel+rstrcl-rstc+tlc+tbr4. all ...201222937565
cholera epidemiology in nigeria: an overview.cholera is an acute diarrhoeal infection caused by ingestion of food or water contaminated with the bacterium, vibrio cholera. choleragenic v. cholera o1 and o139 are the only causative agents of the disease. the two most distinguishing epidemiologic features of the disease are its tendency to appear in explosive outbreaks and its predisposition to causing pandemics that may progressively affect many countries and spread into continents. despite efforts to control cholera, the disease continues ...201222937199
single point mutation in vibrio cholerae cytolysin compromises the membrane pore-formation mechanism of the toxin.vibrio cholerae cytolysin (vcc) belongs to the family of β-barrel pore-forming protein toxins. vcc is secreted by the bacteria as water-soluble monomers, which upon binding to target eukaryotic cells form transmembrane heptameric β-barrel channels. high-resolution 3d structures are described both for the water-soluble monomeric form and the transmembrane oligomeric pore; albeit that our understanding of the mechanistic details of the membrane pore-formation process remains incomplete. here, we r ...201222934938
structural and functional importance of outer membrane proteins in vibrio cholerae flagellum.vibrio cholerae has a sheath-covered monotrichous flagellum that is known to contribute to virulence. although the structural organization of the v. cholerae flagellum has been extensively studied, the involvement of outer membrane proteins as integral components in the flagellum still remains elusive. here we show that flagella produced by v. cholerae o1 el tor strain c6706 were two times thicker than those from two other gram-negative bacteria. a c6706 mutant strain (ssy11) devoid of two outer ...201222923112
studies of dynamic protein-protein interactions in bacteria using renilla luciferase complementation are undermined by nonspecific enzyme inhibition.the luciferase protein fragment complementation assay is a powerful tool for studying protein-protein interactions. two inactive fragments of luciferase are genetically fused to interacting proteins, and when these two proteins interact, the luciferase fragments can reversibly associate and reconstitute enzyme activity. though this technology has been used extensively in live eukaryotic cells, split luciferase complementation has not yet been applied to studies of dynamic protein-protein interac ...201222905225
crystal structure of the vgrg1 actin cross-linking domain of the vibrio cholerae type vi secretion system.vibrio cholerae is the cause of the diarrheal disease cholera. v. cholerae produces rtxa, a large toxin of the martx family, which is targeted to the host cell cytosol, where its actin cross-linking domain (acd) cross-links g-actin, leading to f-actin depolymerization, cytoskeleton rearrangements, and cell rounding. these effects on the cytoskeleton prevent phagocytosis and bacterial engulfment by macrophages, thus preventing v. cholerae clearance from the gut. the v. cholerae type vi secretion- ...201222898822
presence of ctx gene cluster in environmental non-o1/o139 vibrio cholerae and its potential clinical significance.the aim of this study was to understand the epidemiological linkage of clinical and environmental isolates of vibrio cholerae and to determine their genotypes and virulence genes content.201222885193
vibrio cholerae/mimicus in fecal microbiota of healthy children in a cholera endemic urban slum setting in kolkata, india.during a double-blind, randomized, placebo-controlled probiotic trial among 3758 children residing in an urban slum in kolkata, india, vibrio cholerae/mimicus was detected in fecal microbiota of healthy children. the importance of this finding in the local, regional and global transmission of cholera is discussed.201222882566
evaluation of tcpf-a2-ctb chimera and evidence of additive protective efficacy of immunizing with tcpf and ctb in the suckling mouse model of cholera.the secreted colonization factor, tcpf, which is produced by vibrio cholerae 01 and 0139, has generated interest as a potential protective antigen in the development of a subunit vaccine against cholera. this study evaluated immunogenicity/protective efficacy of a tcpf holotoxin-like chimera (tcpf-a2-ctb) following intraperitoneal immunization compared to tcpf alone, a tcpf+ctb mixture, or ctb alone. immunization with the tcpf-a2-ctb chimera elicited significantly greater amounts of anti-tcpf ig ...201222879984
multidrug-resistant vibrio cholerae o1 in belgaum, south india.an outbreak of acute diarrhoea occurred in the belgundi area (population 3896) of belgaum taluka (population 815 581) in karnataka, south india, in june 2010. an estimated 16.22 % of people were affected and 0.16 % deaths were reported. vibrio cholerae o1 el tor was isolated from 18 of the 147 stool samples cultured. seven out of eight drinking water samples collected from different sources were found to be grossly contaminated with faecal coliforms. all isolates were multidrug resistant, with s ...201222878247
x-ray structure of salmonella typhimurium uridine phosphorylase complexed with 5-fluorouracil and molecular modelling of the complex of 5-fluorouracil with uridine phosphorylase from vibrio cholerae.uridine phosphorylase (uph), which is a key enzyme in the reutilization pathway of pyrimidine nucleoside metabolism, is a validated target for the treatment of infectious diseases and cancer. a detailed analysis of the interactions of uph with the therapeutic ligand 5-fluorouracil (5-fura) is important for the rational design of pharmacological inhibitors of these enzymes in prokaryotes and eukaryotes. expanding on the preliminary analysis of the spatial organization of the active centre of uph ...201222868762
antibiotic resistance of vibrio cholerae o1 el tor strains from the seventh pandemic in china, 1961-2010.antibiotic resistance is observed with increasing frequency among epidemic vibrio cholerae strains in some countries. in this study, the antibiotic resistance profiles of v. cholerae o1 el tor strains isolated in china from 1961 to 2010 were analysed. the frequency of antibiotic resistance among the seventh pandemic el tor isolates from china remained low, except for resistance to nalidixic acid (45.9%), tetracycline (11%) and trimethoprim/sulfamethoxazole (38.5%). all test strains in the first ...201222867881
holliday junction affinity of the base excision repair factor endo iii contributes to cholera toxin phage integration.toxigenic conversion of vibrio cholerae bacteria results from the integration of a filamentous phage, ctx phage. integration is driven by the bacterial xer recombinases, which catalyse the exchange of a single pair of strands between the phage single-stranded dna and the host double-stranded dna genomes; replication is thought to convert the resulting pseudo-holliday junction (hj) intermediate into the final recombination product. the natural tendency of the xer recombinases to recycle hj interm ...201222863778
antimicrobial resistance of vibrio cholerae o1 isolated during a cholera epidemic in 2011 in dry season in cote d'ivoire. 201222842949
third-generation cephalosporin-resistant vibrio cholerae, india.vibrio cholerae resistance to third-generation cephalosporins is rarely reported. we detected a strain that was negative for extended-spectrum β-lactamase and positive for the ampc disk test, modified hodge test, and edta disk synergy test and harbored the bladha-1 and blandm-1 genes. the antimicrobial drug susceptibility profile of v. cholerae should be monitored.201222840562
nontoxigenic vibrio cholerae septicemia in an immunocompromised patient.we report a recent case of non-o1, non-o139, nontoxigenic vibrio cholerae septicemia in a post-liver-transplant immunocompromised patient associated with prior seafood consumption. non-o1, non-o139 v. cholerae strains have been reported in several cases of extraintestinal infections and seem to be emerging infectious agents especially in patients with immunocompromising conditions.201222830064
antibacterial & antitoxic effects of the cardiovascular drug lacidipine in an animal model.vibrio cholerae produces acute infection by liberating potent enterotoxin, called cholera toxin in human intestine. cardiovascular drug lacidipine possessing powerful in vitro action against v. cholerae was tested to determine its possible activity against a toxigenic v. cholerae strain in an established animal model.201222825612
identification and characterization of the functional toxboxes in the vibrio cholerae cholera toxin promoter.following the consumption of contaminated food or water by a human host, the vibrio cholerae bacterium produces virulence factors, including cholera toxin (ct), which directly causes voluminous diarrhea, producing cholera. a complex regulatory network controls virulence gene expression and responds to various environmental signals and transcription factors. ultimately, toxt, a member of the arac/xyls transcription regulator family, is responsible for activating the transcription of the virulence ...201222821976
occurrence of toxigenic vibrio cholerae in accessible water sources of cholera endemic foci in india. 201222814165
phenotypic and genetic characterization of vibrio cholerae o1 clinical isolates collected through national antimicrobial resistance surveillance network in nepal.cholera occurs in sporadic cases and outbreaks in nepal each year. vibrio cholerae o1 (n = 522) isolated during 2007-2010 from diarrheal patients at 10 different hospital laboratories in nepal were characterized. biochemical and serologic identifications showed that all the isolates belonged to serogroup o1, el tor biotype. except 72 isolates of inaba serotype isolated in the year 2007, all the remaining isolates were of ogawa serotype. all isolates were resistant to nalidixic acid and furazolid ...201222806193
ultrastructural changes in cultured cells under the effect of vibrio cholerae hemagglutinin/protease.electron microscopic study of changes in cultured cells caused by vibrio cholerae recombinant hemagglutinin/protease (ha/p) showed significant structural changes, most pronounced in hela and l-929 cells not forming a compact monolayer with tight junctions between the cells: formation of numerous vesicles on the cell surface and clasmatosis, vacuolation of the cytoplasm, swelling of mitochondria, clarification of their matrix and crist distortions, and increase in the number of lysosomes. cytopla ...201222803110
molecular architecture and assembly principles of vibrio cholerae biofilms.in their natural environment, microbes organize into communities held together by an extracellular matrix composed of polysaccharides and proteins. we developed an in vivo labeling strategy to allow the extracellular matrix of developing biofilms to be visualized with conventional and superresolution light microscopy. vibrio cholerae biofilms displayed three distinct levels of spatial organization: cells, clusters of cells, and collections of clusters. multiresolution imaging of living v. choler ...201222798614
[design and implementation of geographical information system on prevention and control of cholera].to build the geographical information system (gis) database for prevention and control of cholera programs as well as using management analysis and function demonstration to show the spatial attribute of cholera. data from case reporting system regarding diarrhoea, vibrio cholerae, serotypes of vibrio cholerae at the surveillance spots and seafoods, as well as surveillance data on ambient environment and climate were collected. all the data were imported to system database to show the incidence ...201222781421
functional interaction analysis of gm1-related carbohydrates and vibrio cholerae toxins using carbohydrate microarray.the development of analytical tools is important for understanding the infection mechanisms of pathogenic bacteria or viruses. in the present work, a functional carbohydrate microarray combined with a fluorescence immunoassay was developed to analyze the interactions of vibrio cholerae toxin (ctx) proteins and gm1-related carbohydrates. ctx proteins were loaded onto the surface-immobilized gm1 pentasaccharide and six related carbohydrates, and their binding affinities were detected immunological ...201222770420
broad spectrum pro-quorum-sensing molecules as inhibitors of virulence in vibrios.quorum sensing (qs) is a bacterial cell-cell communication process that relies on the production and detection of extracellular signal molecules called autoinducers. qs allows bacteria to perform collective activities. vibrio cholerae, a pathogen that causes an acute disease, uses qs to repress virulence factor production and biofilm formation. thus, molecules that activate qs in v. cholerae have the potential to control pathogenicity in this globally important bacterium. using a whole-cell high ...201222761573
human epithelial cells stimulated with vibrio cholerae produce thymic stromal lymphopoietin and promote dendritic cell-mediated inflammatory th2 response.vibrio cholerae induces acute inflammatory response at intestinal epithelial surface; the underlying cellular immune mechanisms for such effects are largely unexplored. mucosal immune response is controlled by crosstalk between the intestinal epithelial cells (ecs) and dendritic cells (dcs). an ec-derived cytokine thymic stromal lymphopoietin (tslp) has been found a critical regulator of several human inflammatory conditions. tslp is highly elevated in ecs stimulated with v. cholerae and its rec ...201222750414
cholera.cholera is an acute, secretory diarrhoea caused by infection with vibrio cholerae of the o1 or o139 serogroup. it is endemic in more than 50 countries and also causes large epidemics. since 1817, seven cholera pandemics have spread from asia to much of the world. the seventh pandemic began in 1961 and affects 3-5 million people each year, killing 120,000. although mild cholera can be indistinguishable from other diarrhoeal illnesses, the presentation of severe cholera is distinct, with pronounce ...201222748592
epidemiology and potential land-sea transfer of enteric bacteria from terrestrial to marine species in the monterey bay region of california.marine mammals are at risk for infection by fecal-associated zoonotic pathogens when they swim and feed in polluted nearshore marine waters. because of their tendency to consume 25-30% of their body weight per day in coastal filter-feeding invertebrates, southern sea otters (enhydra lutris nereis) can act as sentinels of marine ecosystem health in california. feces from domestic and wildlife species were tested to determine prevalence, potential virulence, and diversity of selected opportunistic ...201222740531
the regulatory network of natural competence and transformation of vibrio cholerae.the human pathogen vibrio cholerae is an aquatic bacterium frequently encountered in rivers, lakes, estuaries, and coastal regions. within these environmental reservoirs, the bacterium is often found associated with zooplankton and more specifically with their chitinous exoskeleton. upon growth on such chitinous surfaces, v. cholerae initiates a developmental program termed "natural competence for genetic transformation." natural competence for transformation is a mode of horizontal gene transfe ...201222737089
changing trend of persistent diarrhoea in young children over two decades: observations from a large diarrhoeal disease hospital in bangladesh.we studied the changing trend and factors associated with persistent diarrhoea (pd) in under-five children presenting to a large diarrhoeal disease hospital in urban dhaka, bangladesh, over the last two decades.201222734659
comparative structural analysis of two proteins belonging to quorum sensing system in vibrio cholerae.vibrio cholerae uses quorum sensing communication system to interact with other bacteria and for gauzing environmental parameters. this organism dwells equally well in both human host and aquatic environments. quorum sensing regulates multitude of activities and is one of the lucrative targets presently pursued for drug design in bacteria to encounter virulence. histidine phosphotransfer protein luxu and response regulator luxo of v. cholerae are known to play important roles in biofilms and vir ...201222731847
the low-resolution solution structure of vibrio cholerae hfq in complex with qrr1 srna.in vibrio cholerae, the rna binding protein and chaperone hfq (vchfq) facilitates the pairing of the quorum regulatory rna (qrr) small regulatory rnas (srnas) to the 5' untranslated regions of the mrnas for a number of global regulators that modulate the expression of virulence genes. this qrr-mediated srna circuit is an attractive antimicrobial target, but characterization at the molecular level is required for this to be realized. here, we investigate the interactions between vchfq and the qrr ...201222730296
characterization of the rpon regulon reveals differential regulation of t6ss and new flagellar operons in vibrio cholerae o37 strain v52.the alternative sigma factor rpon is an essential colonization factor of vibrio cholerae and controls important cellular functions including motility and type vi secretion (t6ss). the rpon regulon has yet to be clearly defined in t6ss-active v. cholerae isolates, which use t6ss to target both bacterial competitors and eukaryotic cells. we hypothesize that t6ss-dependent secreted effectors are co-regulated by rpon. to systemically identify rpon-controlled genes, we used chromatin immunoprecipitat ...201222723378
twelve transmembrane helices form the functional core of mammalian mate1 (multidrug and toxin extruder 1) protein.the x-ray structure of the prototypic mate family member, norm from vibrio cholerae, reveals a protein fold composed of 12 transmembrane helices (tmhs), confirming hydropathy analyses of the majority of (prokaryotic and plant) mate transporters. however, the mammalian mates are generally predicted to have a 13(th) tmh and an extracellular c terminus. here we affirm this prediction, showing that the c termini of epitope-tagged, full-length human, rabbit, and mouse mate1 were accessible to antibod ...201222722930
vibrio cholerae vexh encodes a multiple drug efflux pump that contributes to the production of cholera toxin and the toxin co-regulated pilus.the resistance-nodulation-division (rnd) efflux systems are ubiquitous transporters that function in antimicrobial resistance. recent studies showed that rnd systems were required for virulence factor production in vibrio cholerae. the v. cholerae genome encodes six rnd efflux systems. three of the rnd systems (vexb, vexd, and vexk) were previously shown to be redundant for in vitro resistance to bile acids and detergents. a mutant lacking the vexb, vexd, and vexk rnd pumps produced wild-type le ...201222666485
emergence of multidrug-resistant vibrio cholerae o1 biotype el tor in port blair, india. 201222665610
evaluation of a rapid dipstick test for identifying cholera cases during the outbreak.intermittent cholera outbreaks are major problem in many of the states of india. it is essential to identify cholera at the earliest for timely mobilization of public health responses and to abort the outbreaks. the present study was a part of a diarrhoeal outbreak investigation in secunderabad, india, during may 2009 where the usefulness of crystal vc rapid dipstick kit was assessed for detecting the aetiologic agent of the outbreak.201222664501
genome-wide study of the defective sucrose fermenter strain of vibrio cholerae from the latin american cholera epidemic.the 7th cholera pandemic reached latin america in 1991, spreading from peru to virtually all latin american countries. during the late epidemic period, a strain that failed to ferment sucrose dominated cholera outbreaks in the northern brazilian amazon region. in order to understand the genomic characteristics and the determinants of this altered sucrose fermenting phenotype, the genome of the strain iec224 was sequenced. this paper reports a broad genomic study of this strain, showing its corre ...201222662140
site-specific recombination systems in filamentous phages.since the discovery of the integration mechanism of the filamentous phage ctxϕ of vibrio cholerae, integrating filamentous phages have been discovered to be more abundant and diverse than previously recognized. however, the integration systems of filamentous phages have not been fully investigated. the present review provides a short overview on the different strategies employed by filamentous bacteriophages for integration into the host chromosome. this is the first review to describe the diver ...201222661259
periplasmic proteins encoded by vca0261-0260 and vc2216 genes together with copa and cuer products are required for copper tolerance but not for virulence in vibrio cholerae.the bacterial pathogen vibrio cholerae requires colonizination of the human small intestine to cause cholera. the anaerobic and slightly acidic conditions predominating there enhance toxicity of low copper concentrations and create a selective environment for bacteria with evolved detoxifying mechanisms. we reported previously that the vca0260, vca0261 and vc2216 gene products were synthesized only in v. cholerae grown in microaerobiosis or anaerobiosis. here we show that orfs vca0261 and vca026 ...201222653946
interaction of virstatin with human serum albumin: spectroscopic analysis and molecular modeling.virstatin is a small molecule that inhibits vibrio cholerae virulence regulation, the causative agent for cholera. here we report the interaction of virstatin with human serum albumin (hsa) using various biophysical methods. the drug binding was monitored using different isomeric forms of hsa (n form ∼ph 7.2, b form ∼ph 9.0 and f form ∼ph 3.5) by absorption and fluorescence spectroscopy. there is a considerable quenching of the intrinsic fluorescence of hsa on binding the drug. the distance (r) ...201222649528
the role of glycine residues 140 and 141 of subunit b in the functional ubiquinone binding site of the na+-pumping nadh:quinone oxidoreductase from vibrio cholerae.the na(+)-pumping nadh:quinone oxidoreductase (na(+)-nqr) is the main entrance for electrons into the respiratory chain of many marine and pathogenic bacteria. the enzyme accepts electrons from nadh and donates them to ubiquinone, and the free energy released by this redox reaction is used to create an electrochemical gradient of sodium across the cell membrane. here we report the role of glycine 140 and glycine 141 of the nqrb subunit in the functional binding of ubiquinone. mutations at these ...201222645140
cholera vaccine: new preventive tool for endemic countries.cholera is a major global public health problem and remains an important threat in almost every developing country, especially in areas where population overcrowding and poor sanitation are common, such as slums and refugee camps. cholera is one of the most dreaded diseases in the world, in some cases leading to death within 24 h if left untreated. without treatment, severe infection has a mortality rate of 30-50%. in 2007, who recorded 177,963 cholera cases and 4,031 deaths worldwide. however, ...201222634452
a heme degradation enzyme, hutz, from vibrio cholerae.hutz, one of the crucial proteins of the iron uptake system in vibrio cholerae, was purified, which binds to heme at a stoichiometry of 1 : 1. in the presence of ascorbic acid, the hutz-bound heme degrades via the same intermediates observed in heme oxygenase, suggesting that hutz works as a heme degradation enzyme.201222627893
multi-locus variable number tandem repeat analysis of 7th pandemic vibrio cholerae.seven pandemics of cholera have been recorded since 1817, with the current and ongoing pandemic affecting almost every continent. cholera remains endemic in developing countries and is still a significant public health issue. in this study we use multilocus variable number of tandem repeats (vntrs) analysis (mlva) to discriminate between isolates of the 7th pandemic clone of vibrio cholerae.201222624829
purification and characterization of cytotoxin produced by a clinical isolate of vibrio cholerae o54 tv113.vibrio cholerae o54 tv113 isolated from a diarrheal patient produces an extracellular cytotoxin that caused alteration in the morphology of chinese hamster ovary cells manifested as cell shrinkage with intact cell boundaries and finally causing cell death. syncase medium supplemented with lincomycin (50 μg/ml), ph 7.2, and 18 h incubation with shaking at 37 °c supported optimal cytotoxin production. we isolated and purified this cytotoxin to homogeneity by ultrafiltration, 40-80 % ammonium sulfa ...201222618242
neutrophils are essential for containment of vibrio cholerae to the intestine during the proinflammatory phase of infection.cholera is classically considered a noninflammatory diarrheal disease, in comparison to invasive enteric organisms, although there is a low-level proinflammatory response during early infection with vibrio cholerae and a strong proinflammatory reaction to live attenuated vaccine strains. using an adult mouse intestinal infection model, this study examines the contribution of neutrophils to host defense to infection. nontoxigenic el tor o1 v. cholerae infection is characterized by the upregulatio ...201222615254
light-scattering sensor for real-time identification of vibrio parahaemolyticus, vibrio vulnificus and vibrio cholerae colonies on solid agar plate.the three most common pathogenic species of vibrio, vibrio cholerae, vibrio parahaemolyticus and vibrio vulnificus, are of major concerns due to increased incidence of water- and seafood-related outbreaks and illness worldwide. current methods are lengthy and require biochemical and molecular confirmation. a novel label-free forward light-scattering sensor was developed to detect and identify colonies of these three pathogens in real time in the presence of other vibrios in food or water samples ...201222613192
a one dose experimental cholera vaccine.the number of cholera vaccine doses required for immunity is a constraint during epidemic cholera. protective immunity following one dose of multiple vibrio cholerae (vc) colonization factors (inaba lps el tor, tcpa, tcpf, and cbp-a) has not been directly tested even though individual vc colonization factors are the protective antigens. inaba lps consistently induced vibriocidal and protective antibodies at low doses. a lps booster, regardless of dose, induced highly protective secondary sera. v ...201222612159
molecular epidemiology of geographically dispersed vibrio cholerae, kenya, january 2009-may 2010.numerous outbreaks of cholera have occurred in kenya since 1971. to more fully understand the epidemiology of cholera in kenya, we analyzed the genetic relationships among 170 vibrio cholerae o1 isolates at 5 loci containing variable tandem repeats. the isolates were collected during january 2009-may 2010 from various geographic areas throughout the country. the isolates grouped genetically into 5 clonal complexes, each comprising a series of genotypes that differed by an allelic change at a sin ...201222607971
amino acid addition to vibrio cholerae lps establishes a link between surface remodeling in gram-positive and gram-negative bacteria.historically, the o1 el tor and classical biotypes of vibrio cholerae have been differentiated by their resistance to the antimicrobial peptide polymyxin b. however, the molecular mechanisms associated with this phenotypic distinction have remained a mystery for 50 y. both gram-negative and gram-positive bacteria modify their cell wall components with amine-containing substituents to reduce the net negative charge of the bacterial surface, thereby promoting cationic antimicrobial peptide resista ...201222589301
[isolation and function of genes regulating aphb expression in vibrio cholerae].we identified genes that regulate the expression of aphb, the gene encoding a key virulence regulator in vibrio cholerae o1 e1 tor c6706(-).201222587006
spontaneous bacterial empyema due to non-o1, non-o139 vibrio cholerae in a cirrhotic patient with hepatocellular carcinoma.vibrio cholerae is known as a common etiology of epidemic diarrheal disease and rarely causes extra-intestinal infections. in this report, we described a cirrhotic patient with hepatocellular carcinoma who developed spontaneous bacterial empyema due to non-o1, non-o139 v. cholerae. the patient was successfully treated with antimicrobial agents and percutaneous drainage.201222578941
crystal structure of periplasmic catecholate-siderophore binding protein vctp from vibrio cholerae at 1.7 å resolution.vctp, one of the two essential siderophore-binding pbps from the pathogen vibrio cholerae, plays an important role in the transport of enterobactin and vibriobactin, which have quite different configurations of iron coordination, from the periplasm to the inner membrane. the current study reports the crystal structure of vctp from v. cholerae n16961 at 1.7å resolution. a structural comparison of vctp with its homologues and the results of molecular docking indicate that enterobactin and vibrioba ...201222575663
unique core genomes of the bacterial family vibrionaceae: insights into niche adaptation and speciation.the criteria for defining bacterial species and even the concept of bacterial species itself are under debate, and the discussion is apparently intensifying as more genome sequence data is becoming available. however, it is still unclear how the new advances in genomics should be used most efficiently to address this question. in this study we identify genes that are common to any group of genomes in our dataset, to determine whether genes specific to a particular taxon exist and to investigate ...201222574681
characterization of the gm1 pentasaccharide-vibrio cholera toxin interaction using a carbohydrate-based electrochemical system.antibody- or dna-based electrochemical systems have been developed widely for several decades, while carbohydrate-based electrochemical systems have been rarely reported. herein, we used an electrochemical detection system to understand the molecular relationships in carbohydrate-protein interactions that can provide useful information about biological processes in living organisms. this system was also helpful for the development of potent biomedical agents. electrochemical detection was achiev ...201222574310
[point mutation of the virbrio cholerae o139 cef (cho cell elongating factor) gene alters the substrate specificity of its product].sequencing of the cef (cho cell elongating factor) of vibrio cholerae serogroup o139 revealed one nucleotide substitution (c for t in position 2015) in comparison with classical v. cholerae o1 and two substitutions (ac for gt in positions 2014-2015) in comparison with v. cholerae o1 e1 tor. a comparative bioinformatic analysis showed that the substitution determines a threonine residue in position 672 of the cefprotein, while the position is occupied by an isoleucine residue in the classical str ...201222568007
the vc1777-vc1779 proteins are members of a sialic acid-specific subfamily of trap transporters (siapqm) and constitute the sole route of sialic acid uptake in the human pathogen vibrio cholerae.sialic acids are nine-carbon amino sugars that are present on all mucous membranes and are often used by bacteria as nutrients. in pathogenic vibrio the genes for sialic acid catabolism (sac) are known to be important for host colonization, yet the route for sialic acid uptake is not proven. vibrio cholerae contains a tripartite atp-independent periplasmic (trap) transporter, siapqm (vc1777-vc1779), encoded by genes within the vibrio pathogenicity island-2 (vpi-2), which are adjacent to the sac ...201222556361
notes from the field: identification of vibrio cholerae serogroup o1, serotype inaba, biotype el tor strain - haiti, march 2012.on october 20, 2010, an outbreak of cholera was confirmed in haiti for the first time in more than a century. as of april 10, 2012, a total of 534,647 cases, 287,656 hospitalizations, and 7,091 deaths have been reported in haiti as a result of the outbreak. the vibrio cholerae strain that caused the haiti epidemic has been characterized as toxigenic v. cholerae, serogroup o1, serotype ogawa, biotype el tor.201222552208
non-coding srnas regulate virulence in the bacterial pathogen vibrio cholerae.vibrio cholerae is the waterborne bacterium responsible for worldwide outbreaks of the acute, potentially fatal cholera diarrhea. the primary factors this human pathogen uses to cause the disease are controlled by a complex regulatory program linking extracellular signaling inputs to changes in expression of several critical virulence genes. recently it has been uncovered that many non-coding regulatory srnas are important components of the v. cholerae virulence regulon. most of these srnas appe ...201222546941
tlp01, an msha mutant of vibrio cholerae o139 as vaccine candidate against cholera.no commercially live vaccine against cholera caused by vibrio cholerae o139 serogroup is available and it is currently needed. virulent o139 strain crc266 was genetically modified by firstly deleting multiple copies of the filamentous phage ctxφ, further tagging by insertion of the endoglucanase a coding gene from clostridium thermocellum into the hemagglutinin/protease gene and finally deleting the msha gene, just to improve the vaccine biosafety. one of the derived strains designated as tlp01 ...201222546527
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