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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
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
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
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
antibacterial activity of a novel fatty acid (14e, 18e, 22e, 26e)-methyl nonacosa-14, 18, 22, 26 tetraenoate isolated from amaranthus spinosus.amaranthus spinosus linn. (amaranthaceae), commonly known as ''spiny pigweed'', is used in both indian traditional system and folk medicine for treatment of infectious diseases for a long time in several traditional herbal medicinal preparations. a novel fatty acid [(14e, 18e, 22e, 26e)-methyl nonacosa-14, 18, 22, 26 tetraenoate] is the major metabolite present.201627043360
[n-acetyl-β-d-glucosaminidase of vibrio cholerae].study n-acetyl-β-d-glucosaminidase (chitobiase) (ec 3.2.1.30) in strains of vibrio cholerae of o1/non-o1 serogroups of various origin, that is a component of chitinolytic complex taking into account object of isolation and epidemiologic significance of strains.201627228670
synthesis and biological evaluation of 5,7-dihydroxyflavanone derivatives as antimicrobial agents.a series of 5,7-dihydroxyflavanone derivatives were efficiently synthesized. their antimicrobial efficacy on gram-negative, gram-positive bacteria and yeast were evaluated. among these compounds, most of the halogenated derivatives exhibited the best antimicrobial activity against gram-positive bacteria, the yeast saccharomyces cerevisiae, and the gram-negative bacterium vibrio cholerae. the cytotoxicities of these compounds were low as evaluated on hepg2 cells using a cell viability assay. this ...201627210435
the unusual redox properties of c-type oxidases.cytochrome cbb3 (also known as c-type) oxidases belong to the family of heme-copper terminal oxidases which couple at the end of the respiratory chain the reduction of molecular oxygen into water and the pumping of protons across the membrane. they are expressed most often at low pressure of o2 and they exhibit a low homology of sequence with the cytochrome aa3 (a-type) oxidases found in mitochondria. their binuclear active site comprises a high-spin heme b3 associated with a cub center. the pro ...201627664317
characterization of prohibitin 1 as a host partner of vibrio vulnificus rtxa1 toxin.rtxa1 toxin, which results in cytoskeletal rearrangement, contact cytotoxicity, hemolysis, tissue invasion, and lethality in mice, is the most potent cytotoxic virulence factor of vibrio vulnificus. bioinformatics analysis of rtxa1 predicted 4 functional domains that presumably performed discrete functions during host cell killing. v. vulnificus rtxa1 has a unique domain designated as rtxa1-d2, corresponding to amino acids 1951-2574, which is absent in vibrio cholerae multifunctional-autoprocess ...201626136468
development of lipopolysaccharide-mimicking peptides and their immunoprotectivity against vibrio cholerae serogroup o1.vibrio cholerae serogroup o1 is the main causative agent of cholera diseases defined by life threatening rice watery diarrhea. cholera routine vaccination has failed in controlling epidemics in developing countries because of their hard and expensive production. in this study, our aim was to investigate phage displayed mimotopes that could mimic v. cholerae lipopolysaccharide (lps). although lps of vibrio, as an endotoxin, can stimulate the immune system, thereby making it a suitable candidate f ...201627766741
local and global consequences of flow on bacterial quorum sensing.bacteria use a chemical communication process called quorum sensing (qs) to control collective behaviours such as pathogenesis and biofilm formation(1,2). qs relies on the production, release and group-wide detection of signal molecules called autoinducers. to date, studies of bacterial pathogenesis in well-mixed cultures have revealed virulence factors and the regulatory circuits controlling them, including the overarching role of qs(3). although flow is ubiquitous to nearly all living systems( ...201627571752
pasteurella multocida toxin: targeting mast cell secretory granules during kiss-and-run secretion.pasteurella multocida toxin (pmt), a virulence factor of the pathogenic gram-negative bacterium p. multocida, is a 146 kda protein belonging to the a-b class of toxins. once inside a target cell, the a domain deamidates the α-subunit of heterotrimeric g-proteins, thereby activating downstream signaling cascades. however, little is known about how pmt selects and enters its cellular targets. we therefore studied pmt binding and uptake in porcine cultured intestinal mucosal explants to identify su ...201626763205
anticancer and antibacterial secondary metabolites from the endophytic fungus penicillium sp. cam64 against multi-drug resistant gram-negative bacteria.the emergence of multiple-drug resistance bacteria has become a major threat and thus calls for an urgent need to search for new effective and safe anti-bacterial agents.201627917206
antibacterial and cytotoxic cytochalasins from the endophytic fungus phomopsis sp. harbored in garcinia kola (heckel) nut.the continuous emergence of multidrug-resistant (mdr) bacteria drastically reduced the efficacy of our antibiotic armory and consequently, increased the frequency of therapeutic failure. the search for bioactive constituents from endophytic fungi against mdr bacteria became a necessity for alternative and promising strategies, and for the development of novel therapeutic solutions. we report here the isolation and structure elucidation of antibacterial and cytotoxic compounds from phomopsis sp., ...201627842536
molecular detection of the three major pathogenic vibrio species from seafood products and sediments in tunisia using real-time pcr.vibrio spp. have emerged as a serious threat to human health worldwide. v. parahaemolyticus , v. cholerae , and v. vulnificus pose a considerable public health risk in tunisia because they cause sporadic and epidemic foodborne infections associated with the consumption of raw or undercooked contaminated seafood. more recently, toxr-positive v. alginolyticus was also reported to be a potential source of contaminated seafood. a total of 247 samples, including 113 fishes ( labrus viridis , penaeus ...201628221954
world health organization estimates of the relative contributions of food to the burden of disease due to selected foodborne hazards: a structured expert elicitation.the foodborne disease burden epidemiology reference group (ferg) was established in 2007 by the world health organization (who) to estimate the global burden of foodborne diseases (fbds). this estimation is complicated because most of the hazards causing fbd are not transmitted solely by food; most have several potential exposure routes consisting of transmission from animals, by humans, and via environmental routes including water. this paper describes an expert elicitation study conducted by t ...201626784029
the epidemiology and antimicrobial resistance of cholera cases in iran during 2013.cholera is an endemic diarrheal disease in iran, caused by vibrio cholerae. the epidemiology, transmission route, environmental determinants and antimicrobial resistant pattern of cholera have been changed during recent years. in this study the epidemiology and antimicrobial resistance of cholera in iran during 2013 outbreak was investigated.201628210461
role of non-coding regulatory rna in the virulence of human pathogenic vibrios.in recent decades, the identification of small non-coding rnas in bacteria has revealed an important regulatory mechanism of gene expression involved in the response to environmental signals and to the control of virulence. in the family vibrionaceae, which includes several human and animal pathogens, small non-coding rnas (srnas) are closely related to important processes including metabolism, quorum sensing, virulence, and fitness. studies conducted in silico and experiments using microarrays ...201628123382
the replication initiator of the cholera pathogen's second chromosome shows structural similarity to plasmid initiators.the conserved dnaa-oric system is used to initiate replication of primary chromosomes throughout the bacterial kingdom; however, bacteria with multipartite genomes evolved distinct systems to initiate replication of secondary chromosomes. in the cholera pathogen, vibrio cholerae, and in related species, secondary chromosome replication requires the rctb initiator protein. here, we show that rctb consists of four domains. the structure of its central two domains resembles that of several plasmid ...201628031373
whole-genome sequences of 26 vibrio cholerae isolates.the human pathogen vibrio cholerae employs several adaptive mechanisms for environmental persistence, including natural transformation and type vi secretion, creating a reservoir for the spread of disease. here, we report whole-genome sequences of 26 diverse v. cholerae isolates, significantly increasing the sequence diversity of publicly available v. cholerae genomes.201628007852
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
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