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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
characterization of v. cholerae t3ss-dependent cytotoxicity in cultured intestinal epithelial cells.am-19226 is a pathogenic, non-o1/non-o139 serogroup strain of vibrio cholerae that uses a type 3 secretion system (t3ss) mediated mechanism to colonize host tissues and disrupt homeostasis, causing cholera. co-culturing the caco2-bbe human intestinal epithelial cell line with am-19226 in the presence of bile results in rapid mammalian cell death that requires a functional t3ss. we examined the role of bile, sought to identify the mechanism, and evaluated the contributions of t3ss translocated ef ...201627302486
phenotypic analysis reveals that the 2010 haiti cholera epidemic is linked to a hypervirulent strain.vibrio cholerae o1 el tor strains have been responsible for pandemic cholera since 1961. these strains have evolved over time, spreading globally in three separate waves. wave 3 is caused by altered el tor (aet) variant strains, which include the strain with the signature ctxb7 allele that was introduced in 2010 into haiti, where it caused a devastating epidemic. in this study, we used phenotypic analysis to compare an early isolate from the haiti epidemic to wave 1 el tor isolates commonly used ...201627297393
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
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
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
host, pathogen and environment: a bacterial gbpa gene expression study in response to magnesium environment and presence of prawn carapace and commercial chitin.vibrio parahaemolyticus is a gram-negative halophilic bacterium which is found largely in estuarine and coastal waters. the bacteria has been a main focus in gastro-intestinal infections caused primarily due to the consumption of contaminated seafood. it was shown to survive in magnesium concentrations as high as 300 mm which are toxic to various other micro-organisms. several genes of v. parahaemolyticus were studied, among which gbpa (n-acetyl glucosamine binding protein) was reported in vibri ...201627231485
[possibilities of application of maldi-tof mass-spectrometry for study of carbohydrate-specific receptors for diagnostic bacteriophage el tor].study mechanisms of interaction of diagnostic bacteriophage el tor with sensitive strain vibrio cholerae el tor 18507 using direct protein profiling, identification of constant and variable proteins, taking part in interaction of the phage and cell, as well as carbohydrate-specific phage receptors.201627228677
staying alive: vibrio cholerae's cycle of environmental survival, transmission, and dissemination.infectious diseases kill nearly 9 million people annually. bacterial pathogens are responsible for a large proportion of these diseases, and the bacterial agents of pneumonia, diarrhea, and tuberculosis are leading causes of death and disability worldwide. increasingly, the crucial role of nonhost environments in the life cycle of bacterial pathogens is being recognized. heightened scrutiny has been given to the biological processes impacting pathogen dissemination and survival in the natural en ...201627227302
prevalence and distribution of vibrio spp. in wild aquatic birds of the southern caribbean sea, venezuela, 2011-12.vibrio spp. are associated with waterbirds mainly in temperate latitudes. we evaluated the prevalence and distribution of vibrio spp. from fecal samples of resident and migratory aquatic birds collected during october 2011 and march 2012 at two coastal sites in the tropical southern caribbean sea. we amplified dna by pcr in 40% of samples, resulting in 47% and 36% estimated prevalence for resident and migratory birds in cuare wildlife refuge, and 33% and 44% in margarita island, respectively. we ...201627224211
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
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
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
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
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
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
targeting apha : a new high-throughput screening assay identifies compounds that reduce prime virulence factors of vibrio cholerae.a high-throughput screening (hts) assay was developed for identifying compounds with inhibitory effect on apha, one of the key regulators positively controlling vibrio cholerae pathogenesis. an inhibitory effect on apha was expected to lead to attenuation in the secretion of the major pathogenicity factors of v. cholerae, cholera toxin and toxin co-regulated pilus. the plasmid construct paksb was developed with a kanamycin resistance (kmr) gene under the control of the apha -like promoter for co ...201627174292
sequence variations in the non-coding sequence of ctx phages in vibrio cholerae.this study focused on the variations in the non-coding sequences between ctxb and rstr of various ctx phages. the non-coding sequences of ctx-1 and ctx-cla are phage type-specific. the length of the non-coding region of ctx-1 and ctx-cla is 601 and 730 nucleotides, respectively. the non-coding sequence of ctx phage could be divided into three regions. there is a phage type-specific variable region between two homologous common regions (common regions 1 and 2). the non-coding sequence of rs1 elem ...201627160575
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
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
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
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
[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
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
nitrosative stress response in vibrio cholerae: role of s-nitrosoglutathione reductase.vibrio cholerae, the causative agent of cholera, poses serious threats to humans worldwide. v. cholerae faces host inflammatory response and encounters nitrosative stress before establishing successful colonization. it is not clear how v. cholerae combats nitric oxide and reactive nitrogen species. in the present study, we used three clinical strains of v. cholerae and tested their nitrosative stress response pattern towards sodium nitroprusside (snp) and s-nitrosoglutathione (gsno). among them, ...201628000045
cholera rapid test with enrichment step has diagnostic performance equivalent to culture.cholera rapid diagnostic tests (rdt) could play a central role in outbreak detection and surveillance in low-resource settings, but their modest performance has hindered their broad adoption. the addition of an enrichment step may improve test specificity. we describe the results of a prospective diagnostic evaluation of the crystal vc rdt (span diagnostics, india) with enrichment step and of culture, each compared to polymerase chain reaction (pcr), during a cholera outbreak in south sudan. rdt ...201627992488
origins of pandemic vibrio cholerae from environmental gene pools.some microorganisms can transition from an environmental lifestyle to a pathogenic one(1-3). this ecological switch typically occurs through the acquisition of horizontally acquired virulence genes(4,5). however, the genomic features that must be present in a population before the acquisition of virulence genes and emergence of pathogenic clones remain unknown. we hypothesized that virulence adaptive polymorphisms (vaps) circulate in environmental populations and are required for this transition ...201627991885
ribavirin suppresses bacterial virulence by targeting lysr-type transcriptional regulators.targeting bacterial virulence mechanisms without compromising bacterial growth is a promising strategy to prevent drug resistance. lysr-type transcriptional regulators (lttrs) possess structural conservation across bacterial species and regulate virulence in numerous pathogens, making them attractive targets for antimicrobial agents. we targeted aphb, a vibrio cholerae lttr, which regulates the expression of genes encoding cholera toxin and toxin-co-regulated pilus for inhibitor designing. since ...201627991578
polymer-based oral rehydration solution for treating acute watery diarrhoea.acute diarrhoea is one of the main causes of morbidity and mortality among children in low-income countries. glucose-based oral rehydration solution (ors) helps replace fluid and prevent further dehydration from acute diarrhoea. since 2004, the world health organization (who) has recommended the osmolarity of less than 270 mosm/l (ors ≤ 270) versus greater than 310 mosm/l formulation (ors ≥ 310). polymer-based ors (for example, prepared using rice or wheat) slowly releases glucose and may be sup ...201627959472
haitian variant tcpa in vibrio cholerae o1 el tor strains in national capital region (india). 201627934812
comparison of antibody immobilization strategies in detection of vibrio cholerae by surface plasmon resonance.surface plasmon resonance immunosensor for the detection of bacterial cells was first reported in 1998 with high detection limit as much as 10(7 )cfu/ml. since then, many efforts have been made aiming to lower the detection limit and improve the sensitivity of detection. the aim of this study was to compare the effect of four most frequently used immobilization strategies, including direct physical adsorption (physisorption), covalent immobilization via self-assembled monolayer (sam) formation, ...201627923270
cross-protection against vibrio cholerae infection by monoclonal antibodies against vibrio vulnificus rtxa1/martxvv.gram-negative vibrio species secrete multifunctional autoprocessing repeats-in-toxin (martx) toxins associated with bacterial pathogenesis. here, the cross-reactivity and cross-protectivity of mabs against v. vulnificus rtxa1/martxvv was evaluated. passive administration of any of these mabs (21ra, 24ra, 46ra, 47ra and 50ra) provided strong protection against lethal v. cholerae infection. interestingly, 24ra and 46ra, which map to the cysteine protease domain of v. cholerae martxvc , inhibited c ...201627921342
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
quorum regulated resistance of vibrio cholerae against environmental bacteriophages.predation by bacteriophages can significantly influence the population structure of bacterial communities. vibrio cholerae the causative agent of cholera epidemics interacts with numerous phages in the aquatic ecosystem, and in the intestine of cholera patients. seasonal epidemics of cholera reportedly collapse due to predation of the pathogen by phages. however, it is not clear how sufficient number of the bacteria survive to seed the environment in the subsequent epidemic season. we found that ...201627892495
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
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
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
antimicrobial susceptibility of autochthonous aquatic vibrio cholerae in haiti.we investigated the antimicrobial susceptibility of 50 environmental isolates of vibrio cholerae non-o1/non-o139 collected in surface waters in haiti in july 2012, during an active cholera outbreak. a panel of 16 antibiotics was tested on the isolates using the disk diffusion method and pcr detection of seven resistance-associated genes (stra/b, sul1/2, erma/b, and mefa). all isolates were susceptible to amoxicillin-clavulanic acid, cefotaxime, imipenem, ciprofloxacin, norfloxacin, amikacin, and ...201627818656
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
occurrence of vibrio parahaemolyticus, vibrio cholerae and vibrio vulnificus in the clam ruditapes philippinarum (adams & reeve, 1850) from emilia romagna and sardinia, italy.marine vibrios, vibrio parahaemolyticus, v. vulnificus and v. cholerae are responsible of the majority of food-borne human infections by consumption of bivalve shellfish. the aim of the present study was to ascertain the occurrence of these bacteria, and their potential pathogenicity, in the manila clam r. philippinarum from emilia romagna (er) and sardinia (sr) regions, italy. isolation was performed on chromagar(tm) vibrio with subculture on (thiosulfate-citrate-bile salts-sucrose) agar and m- ...201627800436
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
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
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
cholera cases cluster in time and space in matlab, bangladesh: implications for targeted preventive interventions.cholera remains a serious public health threat in asia, africa and in parts of the americas. three world health organization (who) pre-qualified oral cholera vaccines are now available but their supply is limited, so current supplies must be administered strategically. this requires an improved understanding of disease transmission and control strategies.201627789673
complete genome sequences of two marine vibrio cholerae strains isolated from the south coast of sweden.vibrio cholerae serogroups o1 and o139 are commonly associated with diarrhea, while non-o1-o139 strains may cause wound infections. here, we present the genome sequences of two v. cholerae strains isolated from blue mussels (mytilus edulis) collected in coastal waters of southern sweden.201627789632
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
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
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
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
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