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phylogenetic diversity of vibrio cholerae associated with endemic cholera in mexico from 1991 to 2008.an outbreak of cholera occurred in 1991 in mexico, where it had not been reported for more than a century and is now endemic. vibrio cholerae o1 prototype el tor and classical strains coexist with altered el tor strains (1991 to 1997). nontoxigenic (ctx(-)) v. cholerae el tor dominated toxigenic (ctx(+)) strains (2001 to 2003), but v. cholerae ctx(+) variant el tor was isolated during 2004 to 2008, outcompeting ctx(-) v. cholerae. genomes of six mexican v. cholerae o1 strains isolated during 199 ...201626980836
occurrence and molecular characterisation of vibrio parahaemolyticus in crustaceans commercialised in venice area, italy.infections due to the pathogenic human vibrios, vibrio parahaemolyticus, vibrio cholerae and vibrio vulnificus, are mainly associated with consumption of raw or partially cooked bivalve molluscs. at present, little is known about the presence of vibrio species in crustaceans and the risk of vibriosis associated with the consumption of these products. the aim of the present study was to evaluate the prevalence and concentration of the main pathogenic vibrio spp. in samples of crustaceans (n=143) ...201626773255
imported cholera with acute renal failure after a short business-trip to the philippines, germany, october 2015.a german businessman developed acute watery diarrhoea after a three-day trip to the philippines. he was admitted with severe hypotension and acute renal failure, but recovered with rapid rehydration. vibrio cholerae o1 serotype ogawa was isolated. physicians need to be aware of endemic cholera in asia including the philippines and consider this in their pre-travel advice.201626767388
construction and preclinical evaluation of mmct, a novel mutant cholera toxin adjuvant that can be efficiently produced in genetically manipulated vibrio cholerae.there is an urgent need for new adjuvants that are effective with mucosally administered vaccines. cholera toxin (ct) is the most powerful known mucosal adjuvant but is much too toxic for human use. in an effort to develop a useful mucosal adjuvant we have generated a novel non-toxic mutant ct molecule that retains much of the adjuvant activity of native ct. this was achieved by making the enzymatically active a subunit (cta) recalcitrant to the site-specific proteolytic cleavage ("nicking") req ...201626973069
high-resolution spatial analysis of cholera patients reported in artibonite department, haiti in 2010-2011.cholera is caused by vibrio cholerae, and is transmitted through fecal-oral contact. infection occurs after the ingestion of the bacteria and is usually asymptomatic. in a minority of cases, it causes acute diarrhea and vomiting, which can lead to potentially fatal severe dehydration, especially in the absence of appropriate medical care. immunity occurs after infection and typically lasts 6-36 months. cholera is responsible for outbreaks in many african and asian developing countries, and cause ...201626972509
comparison of the sulfonamide inhibition profiles of the α-, β- and γ-carbonic anhydrases from the pathogenic bacterium vibrio cholerae.carbonic anhydrases (ca, ec 4.2.1.1) are ubiquitous metalloenzymes, which catalyze the conversion of carbon dioxide (co2) to bicarbonate (hco3(-)) and protons (h(+)). in prokaryotes, the existence of genes encoding for α-, β- and γ-classes suggests that these enzymes play an important role in the prokaryotic physiology. it has been demonstrated, in fact, that their inhibition in vivo leads to growth impairment or growth defects of the microorganism. ultimately, we started to investigate the bioc ...201626972117
the antimicrobial activity of zno nanoparticles against vibrio cholerae: variation in response depends on biotype.the potency of zinc oxide nanoparticles (nps), with a core size of ~7-10nm, to inhibit cholera disease was investigated by demonstrating the effect on two biotypes (classical and el tor) of o1 serogroup of vibrio cholerae-el tor was more susceptible both in planktonic and in biofilm forms. interaction with zno np results in deformed cellular architecture. increased fluidity and depolarization of membrane, and protein leakage further confirmed the damages inflicted on vibrio by np. np was shown t ...201626970029
strategies to prevent cholera introduction during international personnel deployments: a computational modeling analysis based on the 2010 haiti outbreak.introduction of vibrio cholerae to haiti during the deployment of united nations (un) peacekeepers in 2010 resulted in one of the largest cholera epidemics of the modern era. following the outbreak, a un-commissioned independent panel recommended three pre-deployment intervention strategies to minimize the risk of cholera introduction in future peacekeeping operations: screening for v. cholerae carriage, administering prophylactic antimicrobial chemotherapies, or immunizing with oral cholera vac ...201626812236
anion inhibition studies of the β-carbonic anhydrase from the pathogenic bacterium vibrio cholerae.the genome of the pathogenic bacterium vibrio cholerae encodes for three carbonic anhydrases (cas, ec 4.2.1.1) belonging to the α-, β- and γ-classes. here we report and anion inhibition study of the β-ca, vchcaβ with anions and other small molecules which inhibit metalloenzymes. the best vchcaβ anion inhibitors were sulfamide, sulfamate, phenylboronic acid and phenylarsonic acid, which showed kis in the range of 54-86μm. diethyldithiocarbonate was also an effective vchcaβ inhibitor, with an inhi ...201626853167
enterobacteria and vibrio from macrobrachium amazonicum prawn farming in fortaleza, ceará, brazil.to investigate the isolation of enterobacteria associated with macrobrachium amazonicum (m. amazonicum) farming and evaluate the in vitro antimicrobial susceptibility of vibrio strains.201626851782
sulfonamide inhibition studies of the β-carbonic anhydrase from the pathogenic bacterium vibrio cholerae.the genome of the pathogenic bacterium vibrio cholerae encodes for three carbonic anhydrases (cas, ec 4.2.1.1) belonging to the α-, β- and γ-classes. vchca, the α-ca from this species was investigated earlier, whereas the β-class enzyme, vchcaβ was recently cloned, characterized kinetically and its x-ray crystal structure reported by this group. here we report an inhibition study with sulfonamides and one sulfamate of this enzyme. the best vchcaβ inhibitors were deacetylated acetazolamide and me ...201626850377
role of vibrio cholerae exochitinase chia2 in horizontal gene transfer.vibrio cholerae exochitinase chia2 plays a key role in acquisition of nutrients by chitin hydrolysis in the natural environment as well as in pathogenesis in the intestinal milieu. in this study we demonstrate the importance of chia2 in horizontal gene transfer in the natural environment. we found that the expression of chia2 and tfox, the central regulator of v. cholerae horizontal gene transfer, varied with changes in environmental conditions. the activity of chia2 was also dependent on these ...201626849349
characterization of environmental vibrio cholerae serogroups o1 and o139 in the pearl river estuary, china.toxigenic isolates of vibrio cholerae serogroups o1 and o139 from aquatic reservoirs are a key source for recurrent epidemics of cholera in human populations. however, we do not have an optimal understanding of the microbiology of the strains within these reservoirs, particularly outside of the time periods when there are active cholera cases in the surrounding community. the main objective of the present study was to identify and characterize v. cholerae o1 and o139 in the pearl river estuary a ...201626674584
a monoclonal antibody that targets the conserved core/lipid a region of lipopolysaccharide affects motility and reduces intestinal colonization of both classical and el tor vibrio cholerae biotypes.vibrio cholerae is the causative agent of cholera, an acute diarrheal disease that remains endemic in many parts of the world. the mechanisms underlying immunity to cholera remain poorly defined, though it is increasingly clear that protection is associated with antibodies against lipopolysaccharide (lps). here we report that zac-3, a monoclonal antibody against the core/lipid a region of v. cholerae lps is a potent inhibitor of v. cholerae flagellum-based motility in viscous and liquid environm ...201627773473
in silico identification of outer membrane protein (omp) and subunit vaccine design against pathogenic vibrio cholerae.virulence-related outer membrane proteins (omps) are expressed in bacteria (gram-negative) such as v. cholerae and are vital to bacterial invasion in to eukaryotic cell and survival within macrophages that could be best candidate for development of vaccine against v. cholerae. applying in silico approaches, the 3-d model of the omp was developed using swiss model server and validated byprosa and procheck web server. the continuous stretch of amino acid sequences 26mer: rtrsnsglltwgdkqtitleygdpal ...201627769003
quantification of vibrio species in oysters from the gulf of mexico with two procedures based on mpn and pcr.oysters can accumulate potentially pathogenic water bacteria. the objective of this study was to compare two procedures to quantify vibrio species present in oysters to determine the most sensitive method. we analyzed oyster samples from the gulf of mexico, commercialized in mexico city. the samples were inoculated in tubes with alkaline peptone water (apw), based on three tubes and four dilutions (10(-1) to 10(-4)). from these tubes, the first quantification of vibrio species was performed (mos ...201627709461
retrospective analysis of serotype switching of vibrio cholerae o1 in a cholera endemic region shows it is a non-random process.genomic data generated from clinical vibrio cholerae o1 isolates collected over a five year period in an area of kolkata, india with seasonal cholera outbreaks allowed a detailed genetic analysis of serotype switching that occurred from ogawa to inaba and back to ogawa. the change from ogawa to inaba resulted from mutational disruption of the methyltransferase encoded by the wbet gene. re-emergence of the ogawa serotype was found to result either from expansion of an already existing ogawa clade ...201627706170
effects of chromosomal deletion of the operon encoding the multiple resistance and ph-related antiporter in vibrio cholerae.to examine the possible physiological significance of mrp, a multi-subunit cation/proton antiporter from vibrio cholerae, a chromosomal deletion δmrp of v. cholerae was constructed and characterized. the resulting mutant showed a consistent early growth defect in lb broth that became more evident at elevated ph of the growth medium and increasing na+ or k+ loads. after 24 h incubation, these differences disappeared likely due to the concerted effort of other cation pumps in the mrp mutant. pheno ...201627902431
selective and efficient elimination of vibrio cholerae with a chemical modulator that targets glucose metabolism.vibrio cholerae, a gram-negative bacterium, is the causative agent of pandemic cholera. previous studies have shown that the survival of the seventh pandemic el tor biotype v. cholerae strain n16961 requires production of acetoin in a glucose-rich environment. the production of acetoin, a neutral fermentation end-product, allows v. cholerae to metabolize glucose without a ph drop, which is mediated by the production of organic acid. this finding suggests that inhibition of acetoin fermentation c ...201627900286
travel-associated vibrio cholerae o1 el tor, russia. 201627767910
effectiveness of one dose of oral cholera vaccine in response to an outbreak: a case-cohort study.oral cholera vaccines represent a new effective tool to fight cholera and are licensed as two-dose regimens with 2-4 weeks between doses. evidence from previous studies suggests that a single dose of oral cholera vaccine might provide substantial direct protection against cholera. during a cholera outbreak in may, 2015, in juba, south sudan, the ministry of health, médecins sans frontières, and partners engaged in the first field deployment of a single dose of oral cholera vaccine to enhance the ...201627765293
a five-year study on the epidemiological approaches to cholera in iran.cholera is considered a key indicator of social development but still is reported in various cities of iran. the present study aimed to analyze the available information regarding cholera outbreaks since 2010 in iran.201627757199
toxigenic vibrio cholerae o1 in vegetables and fish raised in wastewater irrigated fields and stabilization ponds during a non-cholera outbreak period in morogoro, tanzania: an environmental health study.cholera, one of the world's deadliest infectious diseases, remains rampant and frequent in tanzania and thus hinders existing control measures. the present study was undertaken to evaluate the occurrence of toxigenic vibrio cholerae o1 in wastewater, fish and vegetables during a non-outbreak period in morogoro, tanzania.201627756420
origins of the current seventh cholera pandemic.vibrio cholerae has caused seven cholera pandemics since 1817, imposing terror on much of the world, but bacterial strains are currently only available for the sixth and seventh pandemics. the el tor biotype seventh pandemic began in 1961 in indonesia, but did not originate directly from the classical biotype sixth-pandemic strain. previous studies focused mainly on the spread of the seventh pandemic after 1970. here, we analyze in unprecedented detail the origin, evolution, and transition to pa ...201627849586
phenotypic and antibiogram pattern of v. cholerae isolates from a tertiary care hospital in mumbai during 2004-2013: a retrospective cross-sectional study.cholera is a major gastroenteric disease with reports on fluctuation and resistance. hence, the objective is to determine the trend in seasonality, resistance pattern, prevalent biotypes, serotypes and phage types between 2004 and 2013 among vibrio cholerae isolates.201627888174
adherence to intestinal cells promotes biofilm formation in vibrio cholerae.vibrio cholerae, the etiological agent of cholera, is known to form biofilms to persist in the environment. it is demonstrated here that even during infection, biofilm genes are upregulated, and microscopic observation indicated that biofilm formation is initiated almost immediately after adherence of v. cholerae to intestinal cells. about 7-fold upregulation of the biofilm regulatory gene vpst was observed within 30 minutes of adherence of v. cholerae to the intestinal cell line int 407, and a ...201627638940
a genomic island in vibrio cholerae with vpi-1 site-specific recombination characteristics contains crispr-cas and type vi secretion modules.cholera is a devastating diarrhoeal disease caused by certain strains of serogroup o1/o139 vibrio cholerae. mobile genetic elements such as genomic islands (gis) have been pivotal in the evolution of o1/o139 v. cholerae. perhaps the most important gi involved in cholera disease is the v. cholerae pathogenicity island 1 (vpi-1). this gi contains the toxin-coregulated pilus (tcp) gene cluster that is necessary for colonization of the human intestine as well as being the receptor for infection by t ...201627845364
anoctamin 6 contributes to cl- secretion in accessory cholera enterotoxin (ace)-stimulated diarrhea: an essential role for phosphatidylinositol 4,5-bisphosphate (pip2) signaling in cholera.accessory cholera enterotoxin (ace) of vibrio cholerae has been shown to contribute to diarrhea. however, the signaling mechanism and specific type of cl(-) channel activated by ace are still unknown. we have shown here that the recombinant ace protein induced icl of apical plasma membrane, which was inhibited by classical cacc blockers. surprisingly, an ace-elicited rise of current was neither affected by ano1 (tmem16a)-specific inhibitor t16a(inh)-ao1(tao1) nor by the cystic fibrosis transmemb ...201627799301
nanocarriers from gras zein proteins to encapsulate hydrophobic actives.one factor limiting the expansion of nanomedicines has been the high cost of the materials and processes required for their production. we present a continuous, scalable, low cost nanoencapsulation process, flash nanoprecipitation (fnp) that enables the production of nanocarriers (ncs) with a narrow size distribution using zein corn proteins. zein is a low cost, gras protein (having the fda status of "generally regarded as safe") currently used in food applications, which acts as an effective en ...201627744703
the role of vibrio cholerae haemagglutinin protease (hap) in extra-intestinal infection.based on the diversity of surface o antigen vibrio cholerae can be classified into 206 serogroups. vibrio cholerae is the causative agent of cholera and extra intestinal infections like, septicemia, wound infection and haemorrhagic reactions. pathogenic factors of v. cholerae extra-intestinal infection are yet to be explored.201627790431
a plant from the altiplano of northern chile senecio nutans, inhibits the vibrio cholerae pathogen.in the altiplano of northern chile the plant senecio nutans is habitually used as an infusion to relieve the effects of altitude sickness (locally known as "puna"). it is also used to alleviate the bronchitis, whooping cough, asthma, stomachache, tiredness and fever. the extreme conditions under which these plant grow and scientific data that shows the inhibiting potential of the essential oils of plants of the genus senecio represents great potential in the study of their application to control ...201627795930
characterization of the gluconate utilization system of vibrio cholerae with special reference to virulence modulation.orthologs search identified that the vibrio cholerae gluconate (gnt) utilization system minimally consisted of the entner-doudoroff (ed) pathway (edd and eda) and three other genes, namely gntu, gntk and gntr this system appeared unique by genomic organization of component genes into two operons transcribed in opposite directions. in silico analysis indicated gntu as an inner-membrane protein functioning for transport and gntk as a kinase with cytosolic localization that generates gnt6p, which i ...201627650573
vibrio cholerae laboratory infection of the adult house fly musca domestica.the present study was designed to test the hypothesis that house flies may be capable of specifically harbouring ingested vibrio cholerae in their digestive tracts. flies were continuously fed green fluorescent protein (gfp)-labelled, non-o1/non-o139 environmental strains of v. cholerae. bacterial burdens were quantitatively measured using plate counts and localization was directly observed using confocal microscopy. vibrio cholerae were present in the fly alimentary canal after just 4 h, and re ...201627444689
non-toxigenic environmental vibrio cholerae o1 strain from haiti provides evidence of pre-pandemic cholera in hispaniola.vibrio cholerae is ubiquitous in aquatic environments, with environmental toxigenic v. cholerae o1 strains serving as a source for recurrent cholera epidemics and pandemic disease. however, a number of questions remain about long-term survival and evolution of v. cholerae strains within these aquatic environmental reservoirs. through monitoring of the haitian aquatic environment following the 2010 cholera epidemic, we isolated two novel non-toxigenic (ctxa/b-negative) vibrio cholerae o1. these t ...201627786291
no-go zones for mariner transposition.the property of transposons to randomly insert into target dna has long been exploited for generalized mutagenesis and forward genetic screens. newer applications that monitor the relative abundance of each transposon insertion in large libraries of mutants can be used to evaluate the roles in cellular fitness of all genes of an organism, provided that transposition is in fact random across all genes. in a recent article, kimura and colleagues identified an important exception to the latter assu ...201627729512
cholera.cholera is an acute disease of the gastrointestinal tract caused by vibrio cholerae. cholera was localized in asia until 1817, when a first pandemic spread from india to several other regions of the world. after this appearance, six additional major pandemics occurred during the 19th and 20th centuries, the latest of which originated in indonesia in the 1960s and is still ongoing. in 1854, a cholera outbreak in soho, london, was investigated by the english physician john snow (1813 to 1858). he ...201627726771
major shift of toxigenic v. cholerae o1 from ogawa to inaba serotype isolated from clinical and environmental samples in haiti.in october of 2010, an outbreak of cholera was confirmed in haiti for the first time in more than a century. a single clone of toxigenic vibrio cholerae o1 biotype el tor serotype ogawa strain was implicated as the cause. five years after the onset of cholera, in october, 2015, we have discovered a major switch (ranging from 7 to 100%) from ogawa serotype to inaba serotype. furthermore, using wbet gene sequencing and comparative sequence analysis, we now demonstrate that, among 2013 and 2015 ina ...201627716803
chlorination of household drinking water among cholera patients' households to prevent transmission of toxigenic vibrio cholerae in dhaka, bangladesh: chobi7 trial.household members of cholera patients are at a 100 times higher risk of cholera infections than the general population because of shared contaminated drinking water sources and secondary transmission through poor household hygiene practices. in this study, we investigated the bactericidal concentration of free chlorine required to inactivate vibrio cholerae in household drinking water in dhaka, bangladesh. in laboratory experiments, we found that the concentrations of free chlorine required to i ...201627698273
intrinsic gtpase activity of a ribosomal maturation protein cgta is associated with its inter-domain movement: insights from md simulations and biochemical studies.cgta is an essential ribosome associated gtpase protein of bacteria. it has three domains, viz., obg, gtpase, and c-terminal domain. it is a multifunctional protein and it is being considered as a potential drug target against bacterial infections. despite the importance, cgta's action mechanisms are not well known which warrants further study. towards that goal, we are pursuing biochemical and computational studies in vibrio cholerae cgta (cgtavc). biochemically we found that a single amino aci ...201627677930
role of a sensor histidine kinase chis of vibrio cholerae in pathogenesis.vibrio cholera survival in an aquatic environment depends on chitin utilization pathway that requires two factors, chitin binding protein and chitinases. the chitinases and the chitin utilization pathway are regulated by a two-component sensor histidine kinase chis in v. cholerae. in recent studies these two factors are also shown to be involved in v. cholerae pathogenesis. however, the role played by their upstream regulator chis in pathogenesis is yet to be known. in this study, we investigate ...201627670078
phenotypic and genetic heterogeneity in vibrio cholerae o139 isolated from cholera cases in delhi, india during 2001-2006.incidence of epidemic vibrio cholerae serogroup o139 has declined in cholera endemic countries. however, sporadic cholera caused by v. cholerae o139 with notable genetic changes is still reported from many regions. in the present study, 42 v. cholerae o139 strains isolated from 2001 to 2006 in delhi, india, were retrospectively analyzed to understand their phenotype and molecular characteristics. the majority of isolates were resistant to ampicillin, furazolidone and nalidixic acid. though the i ...201627555841
characterization of vibrio cholerae strains isolated from the nigerian cholera outbreak in 2010.we examined clinical samples from nigerian patients with acute watery diarrhea for vibrio cholerae during the 2010 cholera outbreak. a total of 109 suspected isolates were characterized, but only 57 v. cholerae strains could be confirmed using multiplex real-time pcr as well as rpob sequencing and typed as v. cholerae o:1 ogawa biotype el tor. this finding highlighted the need for accurate diagnosis of cholera in epidemic countries to implement life-saving interventions.201627487957
effects of tcpb mutations on biogenesis and function of the toxin-coregulated pilus, the type ivb pilus of vibrio cholerae.vibrio cholerae is the etiological agent of the acute intestinal disorder cholera. the toxin-coregulated pilus (tcp), a type ivb pilus, is an essential virulence factor of v. cholerae recent work has shown that tcpb is a large minor pilin encoded within the tcp operon. tcpb contributes to efficient pilus formation and is essential for all tcp functions. here, we have initiated a detailed targeted mutagenesis approach to further characterize this salient tcp component. we have identified (thus fa ...201627481929
cell division licensing in the multi-chromosomal vibrio cholerae bacterium.cell division must be coordinated with chromosome replication and segregation to ensure the faithful transmission of genetic information during proliferation. in most bacteria, assembly of the division apparatus, the divisome, starts with the polymerization of a tubulin homologue, ftsz, into a ring-like structure at mid-cell, the z-ring(1). it typically occurs at half of the cell cycle when most of the replication and segregation cycle of the unique chromosome they generally harbour is achieved( ...201627562255
rugose atypical vibrio cholerae o1 el tor responsible for 2009 cholera outbreak in india.vibrio cholerae causes cholera outbreaks in endemic regions where the water quality and sanitation facilities remain poor. apart from biotype and serotype changes, v. cholerae undergoes phase variation, which results in the generation of two morphologically different variants termed smooth and rugose. in this study, 12 rugose (r-vc) and 6 smooth (s-vc) v. cholerae o1 ogawa isolates were identified in a cholera outbreak that occurred in hyderabad, india. antimicrobial susceptibility results showe ...201627561681
vibrio cholerae biofilm growth program and architecture revealed by single-cell live imaging.biofilms are surface-associated bacterial communities that are crucial in nature and during infection. despite extensive work to identify biofilm components and to discover how they are regulated, little is known about biofilm structure at the level of individual cells. here, we use state-of-the-art microscopy techniques to enable live single-cell resolution imaging of a vibrio cholerae biofilm as it develops from one single founder cell to a mature biofilm of 10,000 cells, and to discover the f ...201627555592
multi-scale molecular dynamics study of cholera pentamer binding to a gm1-phospholipid membrane.the ab5 type toxin produced by the vibrio cholerae bacterium is the causative agent of the cholera disease. the cholera toxin (ct) has been shown to bind specifically to gm1 glycolipids on the membrane surface. this binding of ct to the membrane is the initial step in its endocytosis and has been postulated to cause significant disruption to the membrane structure. in this work, we have carried out a combination of coarse-grain and atomistic simulations to study the binding of ct to a membrane m ...201627474868
sequences of a co-existing sxt element, a chromosomal integron (ci) and an inca/c plasmid and their roles in multidrug resistance in a vibrio cholerae o1 el tor strain.the ongoing seventh cholera pandemic is attributed to vibrio cholerae o1 el tor biotype strains. although antibiotic therapy ameliorates symptoms in patients and reduces pathogen transfer to the environment, multidrug resistance remains a major clinical threat. an o1 el tor strain isolated from a patient in 1998 was intermediate or resistant to 13 antibiotics and could potentially produce extended-spectrum β-lactamase (esbl), which is very rare in o1 strains. using genome sequencing, three relev ...201627470490
isolation and identification of vibrio cholerae and vibrio parahaemolyticus from prawn (penaeus monodon) seafood: preservation strategies.bacterial diseases are one of the major problems which affects the production, development and expansion of aqua culture. vibrio sp. are widespread in marine and estuarine environments. the several pathogenic species are commonly associated with outbreaks of vibrio species and it is mainly associated with food poisonings. in this research, the occurrence of vibrio sp. was studied by the isolation and it is confirmed by the biochemical methods. the growth rate was studied by changing the differen ...201627457973
vibrio cholerae leuo links the toxr regulon to expression of lipid a remodeling genes.vibrio cholerae is an intestinal pathogen that causes the diarrheal disease cholera. colonization of the intestine depends upon the expression of genes that allow v. cholerae to overcome host barriers, including low ph, bile acids, and the innate immune system. toxr is a major contributor to this process. toxr is a membrane-spanning transcription factor that coordinates gene expression in response to environmental cues. in previous work we showed that toxr upregulated leuo expression in response ...201627550934
molecular evolution and functional divergence of vibrio cholerae.the purpose of this review is to synopsize and highlight the recent subtle genetic changes in cholera causing toxigenic vibrio cholerae with special reference to their virulence, integrating and conjugative elements and toxin-antitoxin systems. it is not intended to cover issues on the whole genome sequence and epidemiology of cholera.201627537830
vibrio cholerae o1 imported from iraq to kuwait, 2015. 201627532267
anion inhibition profiles of α-, β- and γ-carbonic anhydrases from the pathogenic bacterium vibrio cholerae.among the numerous metalloenzymes known to date, carbonic anhydrase (ca, ec 4.2.1.1) was the first zinc containing one, being discovered decades ago. ca is a hydro-lyase, which catalyzes the following hydration-dehydration reaction: co2+h2o⇋hco3(-)+h(+). several ca classes are presently known, including the α-, β-, γ-, δ-, ζ- and η-cas. in prokaryotes, the existence of genes encoding cas from at least three classes (α-, β- and γ-class) suggests that these enzymes play a key role in the physiolog ...201627283786
cholera outbreak caused by drug resistant vibrio cholerae serogroup o1 biotype eltor serotype ogawa in nepal; a cross-sectional study.cholera is a major cause of mortality and morbidity in underdeveloped countries including nepal. recently drug resistance in vibrio cholerae has become a serious problem mainly in developing countries. the main objectives of our study were to investigate the occurrence of vibrio cholerae in stool samples from patients with watery diarrhea and to determine the antimicrobial susceptibility patterns of v. cholerae isolates.201627274815
cholera toxin promotes th17 cell differentiation by modulating expression of polarizing cytokines and the antigen-presenting potential of dendritic cells.cholera toxin (ct), an exotoxin produced by vibrio cholera, acts as a mucosal adjuvant. in a previous study, we showed that ct skews differentiation of cd4 t cells to il-17-producing th17 cells. here, we found that intranasal administration of ct induced migration of migratory dendritic cell (dc) populations, cd103+ dcs and cd11bhi dcs, to the lung draining mediastinal lymph nodes (medln). among those dc subsets, cd11bhi dcs that were relatively immature had a major role in th17 cell differentia ...201627271559
genetic analysis of vibrio parahaemolyticus intestinal colonization.vibrio parahaemolyticus is the most common cause of seafood-borne gastroenteritis worldwide and a blight on global aquaculture. this organism requires a horizontally acquired type iii secretion system (t3ss2) to infect the small intestine, but knowledge of additional factors that underlie v. parahaemolyticus pathogenicity is limited. we used transposon-insertion sequencing to screen for genes that contribute to viability of v. parahaemolyticus in vitro and in the mammalian intestine. our analysi ...201627185914
isolation frequency and susceptibility pattern of non-o1 and non-o139 vibrio cholerae in a tertiary health care laboratory, 1999-2012.in the past decade the importance of non-o1 and non-o139 strains of vibrio cholerae has been highlighted globally. this study aimed to evaluate the frequency and antimicrobial susceptibility profile of non-o1 and non-o139 v. cholerae in pakistan. data of stool specimens yielding growth of non-o1 and non-o139 v. cholerae isolated at a national referral laboratory from 1999 to 2012 were retrospectively analysed and evaluated for resistance to ampicillin, tetracycline, chloramphenicol, co-trimoxazo ...201627180742
phenotypic and genetic characteristics of vibrio cholerae o1 carrying haitian ctxb and attributes of classical and el tor biotypes isolated from silvassa, india.vibrio cholerae o1 biotype el tor, the causative agent of the seventh pandemic, has recently been replaced by strains carrying classical and haitian ctxb in india, haiti and other parts of the world. we conducted phenotypic and genetic tests to characterize v. cholerae o1 isolated between 2012 and 2014 from silvassa, india, to examine the presence of virulence and regulatory genes, seventh pandemic marker, ctxb type and biofilm formation and to study genomic diversity. of the 59 v. cholerae o1, ...201627255911
biofilm formation of vibrio cholerae on stainless steel used in food processing.vibrio cholerae represents a significant threat to human health in developing countries. this pathogen forms biofilms which favors its attachment to surfaces and its survival and transmission by water or food. this work evaluated the in vitro biofilm formation of v. cholerae isolated from clinical and environmental sources on stainless steel of the type used in food processing by using the environmental scanning electron microscopy (esem). results showed no cell adhesion at 4 h and scarce surfac ...201627253749
multi-locus variable number tandem repeat analysis of vibrio cholerae isolates from 2012 to 2013 cholera outbreaks in iran.cholera remains to be an international threat, with high rates of illness and death. in 2012 and 2013, two cholera outbreak happened in iran, affecting lots of people. vibrio cholerae o1 was confirmed as the etiological agent. source identification and controlling the spread of the cholera disease are two critical approaches in cholera outbreaks. in this study, thirty v. cholerae o1 isolates were selected and has been evaluated for antimicrobial resistant as well as molecular typing by multilocu ...201627247094
chironomids' relationship with aeromonas species.chironomids (diptera: chironomidae), also known as non-biting midges, are one of the most abundant groups of insects in aquatic habitats. they undergo a complete metamorphosis of four life stages of which three are aquatic (egg, larva, and pupa), and the adult emerges into the air. chironomids serve as a natural reservoir of aeromonas and vibrio cholerae species. here, we review existing knowledge about the mutual relations between aeromonas species and chironomids. using 454-pyrosequencing of t ...201627242751
spatiotemporal dynamics of vibrio spp. within the sydney harbour estuary.vibrio are a genus of marine bacteria that have substantial environmental and human health importance, and there is evidence that their impact may be increasing as a consequence of changing environmental conditions. we investigated the abundance and composition of the vibrio community within the sydney harbour estuary, one of the most densely populated coastal areas in australia, and a region currently experiencing rapidly changing environmental conditions. using quantitative pcr (qpcr) and vibr ...201627148171
sustained local diversity of vibrio cholerae o1 biotypes in a previously cholera-free country.although the current cholera pandemic can trace its origin to a specific time and place, many variants of vibrio cholerae have caused this disease over the last 50 years. the relative clinical importance and geographical distribution of these variants have changed with time, but most remain in circulation. some countries, such as mexico and haiti, had escaped the current pandemic, until large epidemics struck them in 1991 and 2010, respectively. cholera has been endemic in these countries ever s ...201627143391
conformational flexibility and dynamics of the internal loop and helical regions of the kink-turn motif in the glycine riboswitch by site-directed spin-labeling.site-directed spin-labeling (sdsl) electron paramagnetic resonance (epr) spectroscopy provides a means for a solution state description of site-specific dynamics and flexibility of large rnas, facilitating our understanding of the effects of environmental conditions such as ligands and ions on rna structure and dynamics. here, the utility and capability of epr line shape analysis and distance measurements to monitor and describe site-specific changes in the conformational dynamics of internal lo ...201627427937
are natural reservoirs important for cholera surveillance? the case of an outbreak in a brazilian estuary.paranaguá bay is one of the largest estuarine systems on the southern brazilian coast. the only recorded cholera outbreak in this region since the early 20th century occurred in 1999 and resulted in 467 cases and at least three reported deaths in a population of approx. 150 000 people. this short communication reports historical, unpublished data related to that outbreak. water, zooplankton and bivalve samples were collected and evaluated using direct fluorescence assay to determine whether vibr ...201627416521
comparison of dot-elisa and standard-elisa for detection of the vibrio cholerae toxin in culture supernatants of bacteria isolated from human and environmental samples.a comparison of dot-elisa and standard-elisa was made for detection of vibrio cholerae toxin in culture supernatants of bacteria isolated from human and environmental samples. a total of 293 supernatants were tested in a double blind assay. a correlation of 100 % was obtained between both techniques. the cholera toxin was found in 20 inaba and 3 ogawa strains. positive samples were from seafood (17 samples), potable water (1 sample) and sewage (5 samples). the dot-elisa was useful as the standar ...201627407304
role of indole production on virulence of vibrio cholerae using galleria mellonella larvae model.cell to cell communication facilitated by chemical signals plays crucial roles in regulating various cellular functions in bacteria. indole, one such signaling molecule has been demonstrated to control various bacterial phenotypes such as biofilm formation and virulence in diverse bacteria including vibrio cholerae. the present study explores some key factors involved in indole production and the subsequent pathogenesis of v. cholerae. indole production was higher at 37 °c than at 30 °c, althoug ...201627407302
mechanisms underlying the immune response generated by an oral vibrio cholerae vaccine.mechanistic details underlying the resulting protective immune response generated by mucosal vaccines remain largely unknown. we investigated the involvement of toll-like receptor signaling in the induction of humoral immune responses following oral immunization with dukoral, comparing wild type mice with tlr-2-, tlr-4-, myd88- and trif-deficient mice. although all groups generated similar levels of igg antibodies, the proliferation of cd4+ t-cells in response to v. cholerae was shown to be medi ...201627384558
a small number of phylogenetically distinct clonal complexes dominate a coastal vibrio cholerae population.vibrio cholerae is a ubiquitous aquatic microbe in temperate and tropical coastal areas. it is a diverse species, with many isolates that are harmless to humans, while others are highly pathogenic. most notable among them are strains belonging to the pandemic o1/o139 serogroup lineage, which contains the causative agents of cholera. the environmental selective regimes that led to this diversity are key to understanding how pathogens evolve in environmental reservoirs. a local population of v. ch ...201627371587
heme-independent redox sensing by the heme-nitric oxide/oxygen-binding protein (h-nox) from vibrio cholerae.heme nitric oxide/oxygen (h-nox)-binding proteins act as nitric oxide (no) sensors among various bacterial species. in several cases, they act to mediate communal behavior such as biofilm formation, quorum sensing, and motility by influencing the activity of downstream signaling proteins such as histidine kinases (hiska) in a no-dependent manner. an h-nox/hiska regulatory circuit was recently identified in vibrio cholerae, and the h-nox protein has been spectroscopically characterized. however, ...201627358409
the lake chad basin, an isolated and persistent reservoir of vibrio cholerae o1: a genomic insight into the outbreak in cameroon, 2010.the prevalence of reported cholera was relatively low around the lake chad basin until 1991. since then, cholera outbreaks have been reported every couple of years. the objective of this study was to investigate the 2010/2011 vibrio cholerae outbreak in cameroon to gain insight into the genomic make-up of the v. cholerae strains responsible for the outbreak. twenty-four strains were isolated and whole genome sequenced. known virulence genes, resistance genes and integrating conjugative element ( ...201627191718
[study of composition of plant extracts, possessing antimicrobial effect against vibrio cholerae el tor, using high-performance liquid chromatography].study the composition of plant extracts using high-performance liquid chromatography. (hplc) and evaluation of their antimicrobial effect against vibrio cholerae el tor.201627029119
[typing of vibrio cholerae non o1/non o139 strains, isolated in rostov region in 2014].comparative study of antibiotics resistance and vntr-typing of vibrio cholerae non o1/ non o139 strains, isolated on the territory of rostov region in 2014.201627029109
comparison of inferred relatedness based on multilocus variable-number tandem-repeat analysis and whole genome sequencing of vibrio cholerae o1.vibrio cholerae causes cholera, a severe diarrheal disease. understanding the local genetic diversity and transmission of v. cholerae will improve our ability to control cholera. vibrio cholerae isolates clustered in genetically related groups (clonal complexes, cc) by multilocus variable tandem-repeat analysis (mlva) were compared by whole genome sequencing (wgs). isolates in cc1 had been isolated from two geographical locations. isolates in a second genetically distinct group, cc2, were isolat ...201627190166
independent regulation of type vi secretion in vibrio cholerae by tfox and tfoy.type vi secretion systems (t6sss) are nanomachines used for interbacterial killing and intoxication of eukaryotes. although vibrio cholerae is a model organism for structural studies on t6sss, the underlying regulatory network is less understood. a recent study showed that the t6ss is part of the natural competence regulon in v. cholerae and is activated by the regulator tfox. here, we identify the tfox homolog tfoy as a second activator of the t6ss. importantly, despite inducing the same t6ss c ...201627117415
the resistance of vibrio cholerae o1 el tor strains to the typing phage 919tp, a member of k139 phage family.bacteriophage 919tp is a temperate phage of vibrio cholerae serogroup o1 el tor and is used as a subtyping phage in the phage-biotyping scheme in cholera surveillance in china. in this study, sequencing of the 919tp genome showed that it belonged to the vibrio phage k139 family. the mechanisms conferring resistance to 919tp infection of el tor strains were explored to help understand the subtyping basis of phage 919tp and mutations related to 919tp resistance. among the test strains resistant to ...201627242744
[bacteraemia due to non-toxigenic vibrio cholerae: the risks of eating seafood in a cirrhotic patient]. 201627242157
molecular epidemiology and antibiotic susceptibility of vibrio cholerae associated with a large cholera outbreak in ghana in 2014.ghana is affected by regular cholera epidemics and an annual average of 3,066 cases since 2000. in 2014, ghana experienced one of its largest cholera outbreaks within a decade with more than 20,000 notified infections. in order to attribute this rise in cases to a newly emerging strain or to multiple simultaneous outbreaks involving multi-clonal strains, outbreak isolates were characterized, subtyped and compared to previous epidemics in 2011 and 2012.201627232338
solar-thermal complex sample processing for nucleic acid based diagnostics in limited resource settings.the use of point-of-care (poc) devices in limited resource settings where access to commonly used infrastructure, such as water and electricity, can be restricted represents simultaneously one of the best application fits for poc systems as well as one of the most challenging places to deploy them. of the many challenges involved in these systems, the preparation and processing of complex samples like stool, vomit, and biopsies are particularly difficult due to the high number and varied nature ...201627231636
designing an efficient multi-epitope peptide vaccine against vibrio cholerae via combined immunoinformatics and protein interaction based approaches.cholera continues to be a major global health concern. among different vibrio cholerae strains, only o1 and o139 cause acute diarrheal diseases that are related to epidemic and pandemic outbreaks. the currently available cholera vaccines are mainly lived and attenuated vaccines consisting of v. cholerae virulence factors such as toxin-coregulated pili (tcp), outer membrane proteins (omps), and nontoxic cholera toxin b subunit (ctb). nowadays, there is a great interest in designing an efficient e ...201627107181
erratum for mangat et al., characterization of vcc-1, a novel ambler class a carbapenemase from vibrio cholerae isolated from imported retail shrimp sold in canada. 201627107107
vibrio cholerae non-o1 bacteraemia: description of three cases in the netherlands and a literature review.vibrio cholerae non-o1 serogroup (vcno) bacteraemia is a severe condition with a high case-fatality rate. we report three cases diagnosed in the netherlands, identified during a national microbiological congress, and provide a literature review on vcno bacteraemia. a search strategy including synonyms for 'vcno' and 'bacteraemia' was applied to pubmed, medline, web of science and embase databases. the three cases were reported in elderly male patients after fish consumption and/or surface water ...201627104237
toxr antagonizes h-ns regulation of horizontally acquired genes to drive host colonization.the virulence regulator toxr initiates and coordinates gene expression needed by vibrio cholerae to colonize the small intestine and cause disease. despite its prominence in v. cholerae virulence, our understanding of the direct toxr regulon is limited to four genes: toxt, ompt, ompu and ctxa. here, we determine toxr's genome-wide dna-binding profile and demonstrate that toxr is a global regulator of both progenitor genome-encoded genes and horizontally acquired islands that encode v. cholerae's ...201627070545
molecular characterization of vibrio cholerae isolates from iran 2012 and 2013 outbreaks.the aim of this study was to assess the genetic diversity of vibrio cholerae isolated from 2012 and 2013 outbreaks in iran, with regard to their virulence properties. a total of 20 v. cholerae strains were collected from sistan-baluchestan province of iran during 2012 and 2013 outbreaks. hybridization assays showed the presence of ctx, zot, ace and rstc genes related to ctx and rs1 phages in all of the isolates. pcr assay indicated the concomitant presence of orfs within rtx (1448, 1451) and tlc ...201627060480
three-dimensional architecture of vibrio cholera biofilms. 201627036000
[actual problems of epidemiologic control, laboratory diagnostics and prophylaxis of cholera in russian federation].main problems of system of epidemiologic control for cholera active in russian federation, as well as laboratory diagnostics and vaccine prophylaxis of this especially dangerous infection, that had emerged in the contemporary period of the ongoing 7th pandemic of cholera, are discussed. features of the genome of natural strains of vibrio cholerae of el tor biovar, that possess a poten- tial epidemic threat, as well as problems, that have emerged during isolation of these strains from samples of ...201627029123
pathophysiological mechanisms of diarrhea caused by the vibrio cholerae o1 el tor variant: an in vivo study in mice.cholera is caused by infection with vibrio cholerae. this study aimed to investigate the pathophysiology of diarrhea caused by the v. cholerae o1 el tor variant (el), a major epidemic strain causing severe diarrhea in several regions. in the ligated ileal loop model of el-induced diarrhea in the icr mice, a cystic fibrosis transmembrane conductance regulator (cftr) inhibitor and a calcium-activated chloride channel (cacc) inhibitor similarly inhibited intestinal fluid secretion. in addition, bar ...201627222028
structure, regulation, and inhibition of the quorum-sensing signal integrator luxo.in a process called quorum sensing, bacteria communicate with chemical signal molecules called autoinducers to control collective behaviors. in pathogenic vibrios, including vibrio cholerae, the accumulation of autoinducers triggers repression of genes responsible for virulence factor production and biofilm formation. the vibrio autoinducer molecules bind to transmembrane receptors of the two-component histidine sensor kinase family. autoinducer binding inactivates the receptors' kinase activiti ...201627219477
a transposon screen identifies genetic determinants of vibrio cholerae resistance to high-molecular-weight antibiotics.gram-negative bacteria are notoriously resistant to a variety of high-molecular-weight antibiotics due to the limited permeability of their outer membrane (om). the basis of om barrier function and the genetic factors required for its maintenance remain incompletely understood. here, we employed transposon insertion sequencing to identify genes required for vibrio cholerae resistance to vancomycin and bacitracin, antibiotics that are thought to be too large to efficiently penetrate the om. the s ...201627216069
genome analysis of a clinical isolate of shewanella sp. uncovered an active hybrid integrative and conjugative element carrying an integron platform inserted in a novel genomic locus.shewanella spp. are currently considered to be emerging pathogens that can code for a blaoxa carbapenemase in their chromosome. complete genome analysis of the clinical isolate shewanella sp. sh95 revealed that this strain is a novel species, which shares a lineage with marine isolates. characterization of its resistome showed that it codes for genes drfa15, qach and blaoxa-48. we propose that shewanella sp. sh95 acts as reservoir of blaoxa-48. moreover, analysis of mobilome showed that it conta ...201627215217
response of vibrio cholerae to low-temperature shifts: cspv regulation of type vi secretion, biofilm formation, and association with zooplankton.the ability to sense and adapt to temperature fluctuation is critical to the aquatic survival, transmission, and infectivity of vibrio cholerae, the causative agent of the disease cholera. little information is available on the physiological changes that occur when v. cholerae experiences temperature shifts. the genome-wide transcriptional profile of v. cholerae upon a shift in human body temperature (37°c) to lower temperatures, 15°c and 25°c, which mimic those found in the aquatic environment, ...201627208110
population-level effect of cholera vaccine on displaced populations, south sudan, 2014.following mass population displacements in south sudan, preventive cholera vaccination campaigns were conducted in displaced persons camps before a 2014 cholera outbreak. we compare cholera transmission in vaccinated and unvaccinated areas and show vaccination likely halted transmission within vaccinated areas, illustrating the potential for oral cholera vaccine to stop cholera transmission in vulnerable populations.201627192187
detection and quantification of vibrio cholerae, vibrio parahaemolyticus, and vibrio vulnificus in coastal waters of guinea-bissau (west africa).v. cholerae, v. parahaemolyticus, and v. vulnificus are recognized human pathogens. although several studies are available worldwide, both on environmental and clinical contexts, little is known about the ecology of these vibrios in african coastal waters. in this study, their co-occurrence and relationships to key environmental constraints in the coastal waters of guinea-bissau were examined using the most probable number-polymerase chain reaction (mpn-pcr) approach. all vibrio species were uni ...201626940502
an in silico, in vitro and in vivo investigation of indole-3-carboxaldehyde identified from the seawater bacterium marinomonas sp. as an anti-biofilm agent against vibrio cholerae o1.biofilm formation is a major contributing factor in the pathogenesis of vibrio cholerae o1 (vco1) and therefore preventing biofilm formation could be an effective alternative strategy for controlling cholera. the present study was designed to explore seawater bacteria as a source of anti-biofilm agents against vco1. indole-3-carboxaldehyde (i3c) was identified as an active principle component in marinomonas sp., which efficiently inhibited biofilm formation by vco1 without any selection pressure ...201626939983
the 2002 chandigarh cholera outbreak revisited: utility of maldi-tof as a molecular epidemiology tool.in july 2002, an outbreak of cholera occurred in north india with two separate geographical foci. pulsed field gel electrophoresis (pfge) was previously used in typing a representative sample of these isolates. this study evaluates the usefulness of maldi-tof as an epidemiological tool for typing vibrio cholerae isolates in comparison with pfge and amplified fragment length polymorphisms (aflp). forty-six isolates of v. cholerae isolated from stool of patients affected in the july 2002 outbreak ...201627198622
regulation by toxr-like proteins converges on vttrb expression to control type 3 secretion system-dependent caco2-bbe cytotoxicity in vibrio cholerae.genes carried on the type 3 secretion system (t3ss) pathogenicity island of vibrio cholerae non-o1/non-o139 serogroup strain am-19226 must be precisely regulated in order for bacteria to cause disease. previously reported results showed that both t3ss function and the presence of bile are required to cause caco2-bbe cell cytotoxicity during coculture with strain am-19226. we therefore investigated additional parameters affecting in vitro cell death, including bacterial load and the role of three ...201627021561
microbiological quality assessment of frozen fish and fish processing materials from bangladesh.the present study aims at the microbiological analysis of export oriented frozen fishes, namely, jew fish, tongue sole fish, cuttle fish, ribbon fish, queen fish, and fish processing water and ice from a view of public health safety and international trade. microbiological analysis includes the determination of total viable aerobic count by standard plate count method and enumeration of total coliforms and fecal coliforms by most probable number method. the presence of specific fish pathogens su ...201627019847
a checkpoint control orchestrates the replication of the two chromosomes of vibrio cholerae.bacteria with multiple chromosomes represent up to 10% of all bacterial species. unlike eukaryotes, these bacteria use chromosome-specific initiators for their replication. in all cases investigated, the machineries for secondary chromosome replication initiation are of plasmid origin. one of the important differences between plasmids and chromosomes is that the latter replicate during a defined period of the cell cycle, ensuring a single round of replication per cell. vibrio cholerae carries tw ...201627152358
revisiting the oligomerization mechanism of vibrio cholerae cytolysin, a beta-barrel pore-forming toxin.vibrio cholerae cytolysin (vcc) is a membrane-damaging beta-barrel pore-forming toxin (beta-pft). vcc causes permeabilization of the target membranes by forming transmembrane oligomeric beta-barrel pores. oligomerization is a key step in the mode of action of any beta-pft, including that of vcc. earlier studies have identified some of the key residues in vcc that are directly involved in the generation of the inter-protomer contacts, thus playing critical roles in the oligomerization of the memb ...201627150630
immunosensor based on nanocomposite of nanostructured zirconium oxide and gelatin-a.we have reported the studies related to the fabrication of a nanocomposite, comprising of sol-gel derived inorganic zirconium oxide nanoparticles (zro2 nps) and organic biopolymer gelatin-a (ga), deposited on indium-tin-oxide (ito) coated glass substrate by drop casting method. the ga-zro2/ito electrode was used for immobilization of monoclonal antibodies (ab) specific to antigen vibrio cholerae (vc) followed by bovine serum albumin (bsa) for antigen vc detection using electrochemical techniques ...201626515440
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