Publications

TitleAbstractYear(sorted descending)
Filter
PMID
Filter
[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
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
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
naturally occurring igg antibodies provide innate protection against vibrio cholerae bacteremia by recognition of the outer membrane protein u.cholera epidemics are caused by vibrio cholerae serogroups o1 and o139, whereas strains collectively known as non-o1/non-o139 v. cholerae are found in cases of extraintestinal infections and bacteremia. the mechanisms and factors influencing the occurrence of bacteremia and survival of v. cholerae in normal human serum have remained unclear. we found that naturally occurring igg recognizing v. cholerae outer membrane protein u (ompu) mediates a serum-killing effect in a complement c1q-dependent ...201626934383
architectural transitions in vibrio cholerae biofilms at single-cell resolution.many bacterial species colonize surfaces and form dense 3d structures, known as biofilms, which are highly tolerant to antibiotics and constitute one of the major forms of bacterial biomass on earth. bacterial biofilms display remarkable changes during their development from initial attachment to maturity, yet the cellular architecture that gives rise to collective biofilm morphology during growth is largely unknown. here, we use high-resolution optical microscopy to image all individual cells i ...201626933214
the transmission and antibiotic resistance variation in a multiple drug resistance clade of vibrio cholerae circulating in multiple countries in asia.vibrio cholerae has caused massive outbreaks and even trans-continental epidemics. in 2008 and 2010, at least 3 remarkable cholera outbreaks occurred in hainan, anhui and jiangsu provinces of china. to address the possible transmissions and the relationships to the 7th pandemic strains of those 3 outbreaks, we sequenced the whole genomes of the outbreak isolates and compared with the global isolates from the 7th pandemic. the three outbreaks in this study were caused by a cluster of v. cholerae ...201626930352
non-o1vibrio cholerae bacteremia in an infant, first case report from pakistan.to the best of our knowledge, non-o1 vibrio cholerae (novc) bacteremia has never been documented in pakistan. this case report is the first reported case of bacteremia in an infant due to novc in pakistan. a neonate was admitted to a hospital with fever and no history of diarrhea. the isolate was identified biochemically and serologically and was sensitive to all the drugs tested as per clsi 2014 guidelines.201626927462
us gulf-like toxigenic o1 vibrio cholerae causing sporadic cholera outbreaks in china.cholera is potentially a life threatening disease caused by toxigenic vibrio cholerae. here we report the identification and characterisation of 76 non-7th pandemic clone o1 v. cholerae isolates including 65 clinical isolates from diarrhoeal patients from 2005 to 2014 in zhejiang province, china.201626920786
extraintestinal infections caused by non-toxigenic vibrio cholerae non-o1/non-o139.vibrio cholerae is an aerobic, sucrose fermentative gram-negative bacterium that generally prevails in the environment. pathogenic v. cholerae is well-known as causative agent of acute diarrhea. apart from enteric infections, v. cholerae may also cause other diseases. however, their role in causing extraintestinal infections is not fully known as it needs proper identification and evaluation. four cases of extraintestinal infections due to v. cholerae non-o1/non-o139 have been investigated. the ...201626904017
in vitro inhibition of cholera toxin production in vibrio cholerae by methanol extract of sweet fennel seeds and its components.a newly emerged vibrio cholerae o1 el tor variant strain with multidrug resistance is considered a threat to public health. recent strategies to suppress virulence factors production instead of bacterial growth may lead to less selective pressure for the emergence of resistant strains. the use of spices and their active constituents as the inhibitory agents against cholera toxin (ct) production in v. cholerae may be an alternative approach to treat cholera. in this study, we examined the potenti ...201626902215
chemoproteomic profiling of host and pathogen enzymes active in cholera.activity-based protein profiling (abpp) is a chemoproteomic tool for detecting active enzymes in complex biological systems. we used abpp to identify secreted bacterial and host serine hydrolases that are active in animals infected with the cholera pathogen vibrio cholerae. four v. cholerae proteases were consistently active in infected rabbits, and one, vc0157 (renamed ivap), was also active in human choleric stool. inactivation of ivap influenced the activity of other secreted v. cholerae and ...201626900865
par-1 mediated apoptosis of breast cancer cells by v. cholerae hemagglutinin protease.bacterial toxins have emerged as promising agents in cancer treatment strategy. hemagglutinin (hap) protease secreted by vibrio cholerae induced apoptosis in breast cancer cells and regresses tumor growth in mice model. the success of novel cancer therapies depends on their selectivity for cancer cells with limited toxicity for normal tissues. increased expression of protease activated receptor-1 (par-1) has been reported in different malignant cells. in this study we report that hap induced act ...201626897170
the oral cholera vaccine shanchol™ when stored at elevated temperatures maintains the safety and immunogenicity profile in bangladeshi participants.the oral cholera vaccine (ocv), shanchol™ has shown protective efficacy lasting up to 5 years, however, requirement for a cold chain limits its use in resource poor settings. the study was conducted to determine the safety and immunogenicity of shanchol in adult participants in bangladesh when stored at elevated temperatures.201626896684
adjusting for unmeasured confounding due to either of two crossed factors with a logistic regression model.motivated by an investigation of the effect of surface water temperature on the presence of vibrio cholerae in water samples collected from different fixed surface water monitoring sites in haiti in different months, we investigated methods to adjust for unmeasured confounding due to either of the two crossed factors site and month. in the process, we extended previous methods that adjust for unmeasured confounding due to one nesting factor (such as site, which nests the water samples from diffe ...201626892025
identification of a vibrio cholerae chemoreceptor that senses taurine and amino acids as attractants.vibrio cholerae, the etiological agent of cholera, was found to be attracted by taurine (2-aminoethanesulfonic acid), a major constituent of human bile. mlp37, the closest homolog of the previously identified amino acid chemoreceptor mlp24, was found to mediate taxis to taurine as well as l-serine, l-alanine, l-arginine, and other amino acids. methylation of mlp37 was enhanced upon the addition of taurine and amino acids. isothermal titration calorimetry demonstrated that a purified periplasmic ...201626878914
oligonol promotes anti-aging pathways via modulation of sirt1-ampk-autophagy pathway.oligonol, mainly found in lychee fruit, is an antioxidant polyphenolic compound which has been shown to have anti-inflammatory and anti-cancer properties. the detailed mechanisms by which oligonol may act as an anti-aging molecule have not been determined.201626865910
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
the rna domain vc1 regulates downstream gene expression in response to cyclic diguanylate in vibrio cholerae.in many bacterial species, including the aquatic bacterium and human pathogen vibrio cholerae, the second messenger cyclic diguanylate (c-di-gmp) modulates processes such as biofilm formation, motility, and virulence factor production. by interacting with various effectors, c-di-gmp regulates gene expression or protein function. one type of c-di-gmp receptor is the class i riboswitch, representatives of which have been shown to bind c-di-gmp in vitro. herein, we examined the in vitro and in vivo ...201626849223
vibrio cholerae biofilms and cholera pathogenesis.vibrio cholerae can switch between motile and biofilm lifestyles. the last decades have been marked by a remarkable increase in our knowledge of the structure, regulation, and function of biofilms formed under laboratory conditions. evidence has grown suggesting that v. cholerae can form biofilm-like aggregates during infection that could play a critical role in pathogenesis and disease transmission. however, the structure and regulation of biofilms formed during infection, as well as their role ...201626845681
the bacterial dicarboxylate transporter vcindy uses a two-domain elevator-type mechanism.secondary transporters use alternating-access mechanisms to couple uphill substrate movement to downhill ion flux. most known transporters use a 'rocking bundle' motion, wherein the protein moves around an immobile substrate-binding site. however, the glutamate-transporter homolog gltph translocates its substrate-binding site vertically across the membrane, through an 'elevator' mechanism. here, we used the 'repeat swap' approach to computationally predict the outward-facing state of the na(+)/s ...201626828963
biochemical and full genome sequence analyses of clinical vibrio cholerae isolates in mexico reveals the presence of novel v. cholerae strains.the first week of september 2013, the national epidemiological surveillance system identified two cases of cholera in mexico city. the cultures of both samples were confirmed as vibrio cholerae serogroup o1, serotype ogawa, biotype el tor. initial analyses by pfge and by pcr-amplification of the virulence genes, suggested that both strains were similar, but different from those previously reported in mexico. the following week, four more cases were identified in a community in the state of hidal ...201626828665
necrotizing fasciitis due to vibrio cholerae non-o1/non-o139 after exposure to austrian bathing sites.we report on two cases of necrotizing fasciitis of the lower leg due to nontoxigenic vibrio cholerae (v. cholerae). a 73-year-old woman (case 1) and an 80-year-old man (case 2) were hospitalized with symptoms of necrotizing fasciitis on july 18 and august 15, 2015, respectively. in both cases, symptoms started the day after swimming in local ponds. swabs gained intraoperatively and a blood culture from the male patient, yielded v. cholerae non-o1/non-o139, negative for cholera toxin gene ctx and ...201626825075
notes from the field: ongoing cholera outbreak - kenya, 2014-2016.on january 6, 2015, a man aged 40 years was admitted to kenyatta national hospital in nairobi, kenya, with acute watery diarrhea. the patient was found to be infected with toxigenic vibrio cholerae serogroup o1, serotype inaba. a subsequent review of surveillance reports identified four patients in nairobi county during the preceding month who met either of the kenya ministry of health suspected cholera case definitions: 1) severe dehydration or death from acute watery diarrhea (more than four e ...201626820494
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
randomized controlled trial of hospital-based hygiene and water treatment intervention (chobi7) to reduce cholera.the risk for cholera infection is >100 times higher for household contacts of cholera patients during the week after the index patient seeks hospital care than it is for the general population. to initiate a standard of care for this high-risk population, we developed cholera-hospital-based-intervention-for-7-days (chobi7), which promotes hand washing with soap and treatment of water. to test chobi7, we conducted a randomized controlled trial among 219 intervention household contacts of 82 chole ...201626811968
comparative transcriptome analysis of vibrio splendidus jz6 reveals the mechanism of its pathogenicity at low temperatures.yesso scallop-pathogenic vibrio splendidus strain jz6 was found to have the highest virulence at 10°c, while its pathogenicity was significantly reduced with increased temperature and completely incapacitated at 28°c. in the present study, comparative transcriptome analyses of jz6 and another nonpathogenic v. splendidus strain, tz19, were conducted at two crucial culture temperatures (10°c and 28°c) in order to determine the possible mechanism of temperature regulation of virulence. comparisons ...201626801576
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
clinical and environmental surveillance for vibrio cholerae in resource constrained areas: application during a 1-year surveillance in the far north region of cameroon.biological confirmation of the presence of vibrio cholerae in clinical and environmental samples is often constrained due to resource- and labor-intensive gold standard methods. to develop low-cost, simple, and sustainable surveillance techniques, we modified previously published specimen sampling and culture techniques and applied the use of enriched dipstick testing in conjunction with the use of filter paper for dna specimen preservation during clinical and environmental surveillance in the f ...201626755564
evaluation in cameroon of a novel, simplified methodology to assist molecular microbiological analysis of v. cholerae in resource-limited settings.vibrio cholerae is endemic in south asia and africa where outbreaks of cholera occur widely and are particularly associated with poverty and poor sanitation. knowledge of the genetic diversity of toxigenic v. cholerae isolates, particularly in africa, remains scarce. the constraints in improving this understanding is not only the lack of regular cholera disease surveillance, but also the lack of laboratory capabilities in endemic countries to preserve, store and ship isolates in a timely manner. ...201626735969
hybrid microarray based on double biomolecular markers of dna and carbohydrate for simultaneous genotypic and phenotypic detection of cholera toxin-producing vibrio cholerae.life-threatening diarrheal cholera is usually caused by water or food contaminated with cholera toxin-producing vibrio cholerae. for the prevention and surveillance of cholera, it is crucial to rapidly and precisely detect and identify the etiological causes, such as v. cholerae and/or its toxin. in the present work, we propose the use of a hybrid double biomolecular marker (dbm) microarray containing 16s rrna-based dna capture probe to genotypically identify v. cholerae and gm1 pentasaccharide ...201626735874
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
comparative genomic analysis of two isolates of vibrio cholerae o1 ogawa el tor isolated during outbreak in mariupol in 2011.cholera is a water-borne, severe enteric infection essentially caused by toxigenic strains of vibrio cholera o1 and o139 serogroups. an outbreak of cholera was registered during may-july 2011 in mariupol, ukraine, with 33 cholera cases and 25 carriers of cholera. following this outbreak, the toxigenic strain of v. cholerae 2011el-301 was isolated from seawater in the recreation area of taganrog city on the territory of russia. the aim of our study was to understand genomic features of mariupol i ...201627480918
understanding, monitoring, and controlling biofilm growth in drinking water distribution systems.in drinking water distribution systems (dwds), biofilms are the predominant mode of microbial growth, with the presence of extracellular polymeric substance (eps) protecting the biomass from environmental and shear stresses. biofilm formation poses a significant problem to the drinking water industry as a potential source of bacterial contamination, including pathogens, and, in many cases, also affecting the taste and odor of drinking water and promoting the corrosion of pipes. this article crit ...201627479445
unique clones of vibrio cholerae o1 el tor with haitian type ctxb allele implicated in the recent cholera epidemics from nigeria, africa.the antimicrobial susceptibility patterns and genetic characteristics of vibrio cholerae o1, which is responsible for several cholera epidemics in nigeria, are not reported in detail since 2007. in this study, we screened v. cholerae o1 el tor biotype isolates from cholera cases and water samples from different states to investigate their phenotypic and genetic attributes with special reference to their clonality.201627479360
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
molecular epidemiology of vibrio cholerae o1 in northern vietnam (2007-2009), using multilocus variable-number tandem repeat analysis.cholera is an infectious disease of major concern in vietnam and other asian countries. in 2009, there was a large outbreak of cholera in northern vietnam. to investigate relationships among isolates of the causative pathogen vibrio cholerae in this region since 2007, we carried out a multilocus variable-number tandem repeat analysis (mlva) of 170 isolates collected between 2007 and 2009. a total of 24 mlva types were identified using seven loci. five clones (1-5) were identified using five loci ...201627452304
chemical synthesis of the galacturonic acid containing pentasaccharide antigen of the o-specific polysaccharide of vibrio cholerae o139 and its five fragments.three pentasaccharides, two tetrasaccharides, and a trisaccharide fragment of the o-specific antigen of vibrio cholerae o139 were synthesized by applying 1 + 1, 2 + 1, 3 + 1, and 4 + 1 coupling strategies. the most challenging tasks involved were the synthesis of the 1,2-cis-glycosidic linkage between galactose and the linker (spacer) molecule and final purification of the target multicharged substances. difficulties with final deprotection by hydrogenation/hydrogenolysis caused by the presence ...201627452084
the complete genomic analysis of an imported vibrio cholerae from myanmar in southwest china.we sequenced and analyzed an imported vibrio cholerae from mynamar in 2011 by using whole genome sequencing method in yunnan province, southwest china. other 3 isolates of v. cholerae in yunnan were also sequenced for comparing purpose. illumina hiseq2500 was used and the sequencing results were assembled and annotated. the comparative genomic analysis was also performed with 101 reference strains from china and abroad. the results showed the imported v. cholerae (yn2011004) had two chromosomes ...201627448952
genome sequence of the k139-like phage vcp032 originating from the vibrio cholerae o1 el tor ogawa serotype.vibrio cholerae is the cause of large cholera outbreaks, especially in endemic regions with high poverty and inadequate sanitation. here, we announce the complete genome sequence of the virulence-associated broad host range v. cholerae phage vcp032, including a brief summary of its genotypic and phenotypic features.201627445393
development of an immunosensor using oriented immobilized anti-ompw for sensitive detection of vibrio cholerae by surface plasmon resonance.the first spr sensor for detection of bacteria was reported in 1998 with high detection limit as much as 10(7)cfu/ml. since then, a lot of effort has been made to lower detection limit and increase sensitivity of detection mainly by using of different assay formats, immobilization strategies, suitable antibodies, minimizing non-specific adsorption and improving the quality of spr devices. the aim of this paper is to introduce the potential of an antibody against recombinant outer membrane protei ...201627442077
hybridoma as a specific, sensitive, and ready to use sensing element: a rapid fluorescence assay for detection of vibrio cholerae o1.over the last decade, isolation and purification of monoclonal antibodies, for diagnostic analysis, have been carried out using the hybridoma expression system. the present study describes a novel example of a detection system using hybridoma cells containing antibody against o1 antigen directly for v. cholerae diagnosis, which is a major health problem in many parts of the world, especially in developing countries. this method has advantages such as simplicity, ease of process, and it does not ...201627438715
(1)h, (15)n and (13)c resonance assignments of the c-terminal domain of vibrio cholerae tola protein.vibrio cholerae is the bacterial causative agent of the human disease cholera. non-pathogenic bacterium can be converted to pathogenic following infection by a filamentous phage, ctxφ, that carries the cholera toxin encoding genes. a crucial step during phage infection requires a direct interaction between the ctxφ minor coat protein (piii(ctx)) and the c-terminal domain of v. cholerae tola protein (tolaiiivc). in order to get a better understanding of tola function during the infection process, ...201627436120
survival of vibrio cholerae o1 on fomites.it is well established that the contamination sources of cholera causing bacteria, vibrio cholerae, are water and food, but little is known about the transmission role of the fomites (surfaces that can carry pathogens) commonly used in households. in the absence of appropriate nutrients or growth conditions on fomites, bacteria have been known to assume a viable but non-culturable (vbnc) state after a given period of time. to investigate whether and when v. cholerae o1 assumes such a state, this ...201627430513
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
aaa+ proteases and their role in distinct stages along the vibrio cholerae lifecycle.the facultative human pathogen vibrio cholerae has to adapt to different environmental conditions along its lifecycle by means of transcriptional, translational and post-translational regulation. this study provides a first comprehensive analysis regarding the contribution of the cytoplasmic aaa+ proteases lon, clpp and hslv to distinct features of v. cholerae behaviour, including biofilm formation, motility, cholera toxin expression and colonization fitness in the mouse model. while absence of ...201627345492
structural and functional evidence indicates selective oxygen signaling in caldanaerobacter subterraneus h-nox.acute and specific sensing of diatomic gas molecules is an essential facet of biological signaling. heme nitric oxide/oxygen binding (h-nox) proteins are a family of gas sensors found in diverse classes of bacteria and eukaryotes. the most commonly characterized bacterial h-nox domains are from facultative anaerobes and are activated through a conformational change caused by formation of a 5-coordinate fe(ii)-no complex. members of this h-nox subfamily do not bind o2 and therefore can selectivel ...201627328180
the na+-translocating nadh:quinone oxidoreductase enhances oxidative stress in the cytoplasm of vibrio cholerae.we searched for a source of reactive oxygen species (ros) in the cytoplasm of the human pathogen vibrio cholerae and addressed the mechanism of ros formation using the dye 2',7'-dichlorofluorescein diacetate (dcfh-da) in respiring cells. by comparing v. cholerae strains with or without active na(+)-translocating nadh:quinone oxidoreductase (na(+)-nqr), this respiratory sodium ion redox pump was identified as a producer of ros in vivo the amount of cytoplasmic ros detected in v. cholerae cells pr ...201627325677
vibrio cholerae gbpa elicits necrotic cell death in intestinal cells.vibrio choleraen-acetylglucosamine-binding protein gbpa is a secretory protein that facilitates the initial adherence of bacteria in the human intestine. until now, considerable progress in the characterization of gbpa has been done, yet little is known about its role in host response. our present studies demonstrated that gbpa at the amount secreted in the intestine resulted in decreased cell viability, altered cell morphology, disruption of cell membrane integrity and damage of cellular dna in ...201627324251
genetic relatedness of selected clinical vibrio cholerae o139 isolates from the southern coastal area of china over a 20-year period.vibrio cholerae o139 emerged as a causative agent of epidemic cholera in 1992 in india and bangladesh, and was subsequently reported in china in 1993. the genetic relatedness and molecular characteristics of v. cholerae o139 in guangdong province, located in the southern coastal area of china, remains undetermined. in this study, we investigated 136 clinical v. cholerae o139 isolates from 1993 to 2013 in guangdong. by conventional pcr, 123 (90·4%) isolates were positive for ctxb, ace and zot. se ...201627305977
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
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
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
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
vibriosis, not cholera: toxigenic vibrio cholerae non-o1, non-o139 infections in the united states, 1984-2014.toxigenic strains of vibrio cholerae serogroups o1 and o139 have caused cholera epidemics, but other serogroups - such as o75 or o141 - can also produce cholera toxin and cause severe watery diarrhoea similar to cholera. we describe 31 years of surveillance for toxigenic non-o1, non-o139 infections in the united states and map these infections to the state where the exposure probably originated. while serogroups o75 and o141 are closely related pathogens, they differ in how and where they infect ...201627510301
thiol-based switch mechanism of virulence regulator aphb modulates oxidative stress response in vibrio cholerae.bacterial pathogens display versatile gene expression to adapt to changing surroundings. for example, vibrio cholerae, the causative agent of cholera, utilizes distinct genetic programs to combat reactive oxygen species (ros) in aquatic environments or during host infection. we previously reported that the virulence activator aphb in v. cholerae is involved in ros resistance. here by performing a genetic screen, we show that aphb represses ros resistance gene ohra, which is also repressed by ano ...201627625149
total synthesis of the complete protective antigen of vibrio cholerae o139.the first chemical synthesis of the complete protective o-antigen of a human-disease-causing pathogenic bacterium is described. the synthesis involved a protecting-group strategy that facilitated the regioselectivity of the key transformations, stereoselective glycosylation reactions, and enabled the one-step global deprotection of the completely assembled, fully protected, phosphorylated hexasaccharide by hydrogenation/hydrogenolysis. the final amino-group-functionalized, linker-equipped antige ...201627623688
genetic studies of vibrio cholerae in south west cameroon-a phylogenetic analysis of isolates from the 2010-2011 epidemic.during the cholera outbreak from 2010 to 2011 in cameroon, 33,192 cases with 1,440 deaths (case fatality ratio 4.34%) were reported to the world health organization. of these, the south west region reported 3,120 clinical cases. this region is in the equatorial monsoon climatic subzone of cameroon, close to the coast, raising questions as to whether cases were linked with development of environmental reservoirs.201627617169
redox pathway sensing bile salts activates virulence gene expression in vibrio cholerae.vibrio cholerae, the causative agent of the severe diarrheal disease cholera, has evolved signal transduction systems to control co-ordinately the expression of virulence determinants. it was previously shown that the presence of the bile salts glycocholate and taurocholate in the small intestine causes dimerization of the transmembrane transcription factor tcpp by inducing intermolecular disulphide bonds in the tcpp periplasmic domain. in this study, they further investigated the mechanism of h ...201627610607
sialylation transmogrifies human breast and pancreatic cancer cells into 3d multicellular tumor spheroids using cyclic rgd-peptide induced self-assembly.multicellular tumor spheroids (mts) have been at the forefront of cancer research, designed to mimic tumor-like developmental patterns in vitro. tumor growth in vivo is highly influenced by aberrant cell surface-specific sialoglycan structures on glycoproteins. aberrant sialoglycan patterns that facilitate mts formation are not well defined. matrix-free spheroids from breast mcf-7 and pancreatic panc1 cancer cell lines and their respective tamoxifen (tmx) and gemcitabine (gem) resistant variants ...201627608845
intestinal ameliorative effects of traditional ogi-tutu, vernonia amygdalina and psidium guajava in mice infected with vibrio cholera.cholera, a severe acute watery diarrhea caused by vibrio cholerae is endemic in nigeria with most cases occurring in the rural areas. in south west nigeria, some individuals resort to alternative treatments such as ogi-tutu, psidium guajava and vernonia amygdalina during infections. the effectiveness of these alternatives in the prevention and treatment of v. cholerae infection requires experimental investigation.201627605980
a rare case of necrotizing fasciitis caused by vibrio cholerae o8 in an immunocompetent patient.we report a case of necrotizing fasciitis of the leg caused by vibrio cholerae o8 in a 63-year-old immunocompetent man after he had been fishing in a lake on a croatian island. the strain was cytotoxic, invasive and adhesive and contained a fragment of the gene for el tor-like hemolysin (el tor hlya). after surgical and antibiotic treatment, the patient fully recovered.201627604649
1.65 å resolution structure of the arac-family transcriptional activator toxt from vibrio cholerae.toxt is an arac-family transcriptional activator protein that controls the expression of key virulence factors in vibrio cholerae, the causative agent of cholera. toxt directly activates the expression of the genes that encode the toxin-coregulated pilus and cholera toxin, and also positively auto-regulates its own expression from the tcp promoter. the crystal structure of toxt has previously been solved at 1.9 å resolution (pdb entry 3gbg). in this study, a crystal structure of toxt at 1.65 å r ...201627599865
development of a multiplex pcr for discrimination of the tlc:rs1:ctx array of vibrio cholerae wave 3 el tor strains.vibrio cholerae o1 serogroup wave 3 el tor strains are presently prevalent worldwide. the wave 3 el tor strains contain a tlc:rs1:ctx array on chromosome 1, and no element is integrated on chromosome 2. a multiplex pcr optimized to identify the tlc:rs1:ctx array of wave 3 strains has been developed in this study. by using eight primers, the multiplex pcr can identify the characteristic ctx and rs1 array of wave 3 strains from various arrays of strains belonging to other waves. the four amplified ...201627586526
measuring in vitro atpase activity for enzymatic characterization.adenosine triphosphate-hydrolyzing enzymes, or atpases, play a critical role in a diverse array of cellular functions. these dynamic proteins can generate energy for mechanical work, such as protein trafficking and degradation, solute transport, and cellular movements. the protocol described here is a basic assay for measuring the in vitro activity of purified atpases for functional characterization. proteins hydrolyze atp in a reaction that results in inorganic phosphate release, and the amount ...201627584824
the nucleoid binding protein h-ns biases genome-wide transposon insertion landscapes.transposon insertion sequencing (tis; also known as tnseq) is a potent approach commonly used to comprehensively define the genetic loci that contribute to bacterial fitness in diverse environments. a key presumption underlying analyses of tis datasets is that loci with a low frequency of transposon insertions contribute to fitness. however, it is not known whether factors such as nucleoid binding proteins can alter the frequency of transposon insertion and thus whether tis output may systematic ...201627578758
chemotaxis cluster 1 proteins form cytoplasmic arrays in vibrio cholerae and are stabilized by a double signaling domain receptor dosm.nearly all motile bacterial cells use a highly sensitive and adaptable sensory system to detect changes in nutrient concentrations in the environment and guide their movements toward attractants and away from repellents. the best-studied bacterial chemoreceptor arrays are membrane-bound. many motile bacteria contain one or more additional, sometimes purely cytoplasmic, chemoreceptor systems. vibrio cholerae contains three chemotaxis clusters (i, ii, and iii). here, using electron cryotomography, ...201627573843
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
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
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
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
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
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
transmission of infectious vibrio cholerae through drinking water among the household contacts of cholera patients (chobi7 trial).recurrent cholera causes significant morbidity and mortality among the growing population of dhaka, the capital city of bangladesh. previous studies have demonstrated that household contacts of cholera patients are at >100 times higher risk of cholera during the week after the presentation of the index patient. our prospective study investigated the mode of transmission of vibrio cholerae, the cause of cholera, in the households of cholera patients in dhaka city. out of the total 420 rectal swab ...201627803695
Refresh
firstprev
12345678910...
nextlast
Displaying items 701 - 800 of 24874