| [improvement of laboratory diagnostics of cholera due to genetically altered (hybrid) variants of cholera vibrio biovar el tor]. | improvement of laboratory diagnostics of cholera taking into the account appearance of hybrid variants of cholera vibrio el tor biovar in the 1990s. | 2015 | 25842952 |
| [cholera vibrio biofilm: production, characterization and role in reservation of causative agent in water environment]. | experimental production, characterization and evaluation of the role of cholera vibrio biofilm. | 2015 | 25842946 |
| enzymatic electrochemical detection of epidemic-causing vibrio cholerae with a disposable oligonucleotide-modified screen-printed bisensor coupled to a dry-reagent-based nucleic acid amplification assay. | in this study, we developed a nucleic acid-sensing platform in which a simple, dry-reagent-based nucleic acid amplification assay is combined with a portable multiplex electrochemical genosensor. preparation of an amplification reaction mix targeting multiple dna regions of interest is greatly simplified because the lyophilized reagents need only be reconstituted with ultrapure water before the dna sample is added. the presence of single or multiple target dnas causes the corresponding single-st ... | 2015 | 25835520 |
| complete topology of the rnf complex from vibrio cholerae. | rnf is a redox-driven ion (na(+) and in one case possibly h(+)) transporter present in many prokaryotes. it has been proposed that rnf performs a variety of reactions in different organisms, delivering low-potential reducing equivalents for specific cellular processes. rnf shares strong homology with the na(+)-pumping respiratory enzyme na(+)-nqr, although there are significant differences in subunit and redox cofactor composition. here we report a topological analysis of the six subunits of rnf ... | 2015 | 25831459 |
| a cis-regulatory antisense rna represses translation in vibrio cholerae through extensive complementarity and proximity to the target locus. | as with all facultative pathogens, vibrio cholerae must optimize its cellular processes to adapt to different environments with varying carbon sources and to environmental stresses. more specifically, in order to metabolize mannitol, v. cholerae must regulate the synthesis of mtla, a mannitol transporter protein produced exclusively in the presence of mannitol. we previously showed that a cis-acting small rna (srna) expressed by v. cholerae, mtls, appears to post-transcriptionally downregulate t ... | 2015 | 25826566 |
| "quorum non-sensing": social cheating and deception in vibrio cholerae. | quorum sensing (qs) is widely used by bacteria to coordinate behavior in response to external stimuli. in vibrio cholerae, this process is important for environmental survival and pathogenesis, though, intriguingly, a large percentage of natural isolates are qs deficient. here, we show that qs-deficient mutants can spread as social cheaters by ceasing production of extracellular proteases under conditions requiring their growth. we further show that mutants stimulate biofilm formation and are ov ... | 2015 | 25819968 |
| dimeric wh2 repeats of vopf sequester actin monomers into non-nucleating linear string conformations: an x-ray scattering study. | vopf and vopl are highly similar virulence-factors of vibrio cholerae and vibrio parahaemolyticus respectively that disrupt the host's actin cytoskeleton, using a unique organization in dimerized wh2 repeats. association of dimerized wh2 domains with the barbed face of actin confers multifunctional activities to vopf in vitro, including g-actin sequestration and filament nucleation, barbed end tracking and uncapping. here, small angle x-ray scattering (saxs) measurements of complexes of vopf wit ... | 2015 | 25818509 |
| whole-genome sequencing of a vibrio cholerae el tor strain isolated in the imported cholera focus in siberia. | the draft genome sequence of vibrio cholerae o1 strain i-1263, isolated from a patient in the imported focus in siberia, was determined. the established structural features of the mobile genetic elements indicate stage-by-stage formation of a highly pathogenic v. cholerae clone and promote understanding of the mechanisms of evolutionary pathogen transformations. | 2015 | 25814617 |
| meddling vibrio cholerae murmurs: a neoteric advancement in cholera research. | cholera, a known diarrheal disease is associated with various risk factors like hypovolemic shock, rice watery stools, and death in developing countries. the overuse of antibiotics to treat cholera imposed a selective pressure for the emergence and spread of multi-drug resistant vibrio cholerae strains. the failure of conventional antimicrobial therapy urged the researchers to find an alternative therapy that could meddle the cholera murmurs (quorum sensing). it seems to effectively overcome the ... | 2015 | 25805898 |
| high production of neuraminidase by a vibrio cholerae non-o1 strain--the first possible alternative to toxigenic producers. | vibrio cholerae neuraminidase (vcna) is widely used in biochemical and medical research, in processes for preparing homogenous sialoconjugates, and in the pharmaceutical industry. its production by non-toxigenic strains is quite desirable, in order to avoid the expensive safety measures. here, we report the first method for highly effective production of a novel, purified v. cholerae extracellular neuraminidase from a non-toxigenic strain. the enzyme is highly active, and its properties, as well ... | 2015 | 25805019 |
| scanning the landscape of genome architecture of non-o1 and non-o139 vibrio cholerae by whole genome mapping reveals extensive population genetic diversity. | historically, cholera outbreaks have been linked to v. cholerae o1 serogroup strains or its derivatives of the o37 and o139 serogroups. a genomic study on the 2010 haiti cholera outbreak strains highlighted the putative role of non o1/non-o139 v. cholerae in causing cholera and the lack of genomic sequences of such strains from around the world. here we address these gaps by scanning a global collection of v. cholerae strains as a first step towards understanding the population genetic diversity ... | 2015 | 25794000 |
| identification and characterisation of a novel plasmid-mediated quinolone resistance gene, qnrvc7, in vibrio cholerae of seafood origin. | | 2015 | 25769785 |
| multidrug-resistant vibrio cholerae o1 was responsible for a cholera outbreak in 2013 in bagalkot, north karnataka. | cholera is a major cause of illness in the developing world. during the monsoon season, small sporadic clusters of cholera cases are reported on an annual basis in karnataka, india. during the monsoons of 2013, there was a cholera outbreak in badami, a remote area of bagalkot district in karnataka. the multi-drug-resistant vibrio cholerae o1 serotype ogawa was found to be responsible for this outbreak. on 5 august 2013, a 30-year-old woman presented with severe dehydration and watery diarrhea at ... | 2015 | 25766606 |
| toxigenic vibrio cholerae identified in estuaries of tanzania using pcr techniques. | the current study assessed the occurrence of the vibrio cholerae serogroups o1 and o139 in environmental samples along salinity gradients in three selected estuaries of tanzania both through culture independent methods and by cultured bacteria. occurrence of v. cholerae was determined by pcr targeting the v. cholerae outer membrane protein gene ompw. furthermore, the presence of toxigenic strains and serogroups o1 and o139 was determined using multiplex pcr with specific primers targeting the ch ... | 2015 | 25743072 |
| correction for herrera et al., the vibrio cholerae vpra-vprb two-component system controls virulence through endotoxin modification. | | 2015 | 25736885 |
| mechanism for inhibition of vibrio cholerae toxt activity by the unsaturated fatty acid components of bile. | the gram-negative curved bacillus vibrio cholerae causes the severe diarrheal illness cholera. during host infection, a complex regulatory cascade results in production of toxt, a dna-binding protein that activates the transcription of major virulence genes that encode cholera toxin (ct) and toxin-coregulated pilus (tcp). previous studies have shown that bile and its unsaturated fatty acid (ufa) components reduce virulence gene expression and therefore are likely important signals upon entering ... | 2015 | 25733618 |
| identifying the most sensitive and specific sign and symptom combinations for cholera: results from an analysis of laboratory-based surveillance data from haiti, 2012-2013. | since october 2010, over 700,000 cholera cases have been reported in haiti. we used data from laboratory-based surveillance for diarrhea in haiti to evaluate the sensitivity, specificity, and positive (ppv) and negative predictive values (npv) of the cholera case definitions recommended by the world health organization (who). from april 2012 to may 2013, we tested 1,878 samples from hospitalized patients with acute watery diarrhea; 1,178 (62.7%) yielded vibrio cholerae o1. the sensitivity and sp ... | 2015 | 25732682 |
| a novel triplex quantitative pcr strategy for quantification of toxigenic and nontoxigenic vibrio cholerae in aquatic environments. | vibrio cholerae is a severe human pathogen and a frequent member of aquatic ecosystems. quantification of v. cholerae in environmental water samples is therefore fundamental for ecological studies and health risk assessment. beside time-consuming cultivation techniques, quantitative pcr (qpcr) has the potential to provide reliable quantitative data and offers the opportunity to quantify multiple targets simultaneously. a novel triplex qpcr strategy was developed in order to simultaneously quanti ... | 2015 | 25724966 |
| structure of the type vi secretion system contractile sheath. | bacteria use rapid contraction of a long sheath of the type vi secretion system (t6ss) to deliver effectors into a target cell. here, we present an atomic-resolution structure of a native contracted vibrio cholerae sheath determined by cryo-electron microscopy. the sheath subunits, composed of tightly interacting proteins vipa and vipb, assemble into a six-start helix. the helix is stabilized by a core domain assembled from four β strands donated by one vipa and two vipb molecules. the fold of i ... | 2015 | 25723169 |
| comparative genome analysis of non-toxigenic non-o1 versus toxigenic o1 vibrio cholerae. | pathogenic strains of vibrio cholerae are responsible for endemic and pandemic outbreaks of the disease cholera. the complete toxigenic mechanisms underlying virulence in vibrio strains are poorly understood. the hypothesis of this work was that virulent versus non-virulent strains of v. cholerae harbor distinctive genomic elements that encode virulence. the purpose of this study was to elucidate genomic differences between the o1 serotypes and non-o1 v. cholerae ps15, a non-toxigenic strain, in ... | 2017 | 25722857 |
| typing and antibiogram of vibrio cholerae isolates from a tertiary care hospital in pune: a 3 year study. | a retrospective analysis was done over a period of 3 years (january 2010- december 2012) in a tertiary care hospital, pune, to note the changes in the prevalence and distribution of biotypes, serotypes, antibiotic susceptibility pattern and phage types of vibrio cholerae isolates from clinical samples so as to be vigilant and curtail major outbreak in future. vibrio cholerae isolates were obtained from 4.4% of the 1126 fecal specimens processed from cases of acute watery diarrhea. majority of th ... | 2017 | 25722619 |
| cholera toxin-b (ctxb) antigen expressing salmonella typhimurium polyvalent vaccine exerts protective immune response against vibrio cholerae infection. | live attenuated vaccines are cost effective approach for preventing a broad range of infectious diseases, and thus are of great interest. however, immune-defects can predispose the patient to infections by the vaccine candidate itself. so far, few live vaccine candidates have been designed specifically for immune compromised individuals. recently, we reported a new salmonella typhimurium z234-vaccine strain (periaswamy et al., plos one 2012;7:e45433), which was specifically attenuated in the nad ... | 2015 | 25701672 |
| substrate-dependent activation of the vibrio cholerae vexab rnd efflux system requires vexr. | vibrio cholerae encodes six resistance-nodulation-division (rnd) efflux systems which function in antimicrobial resistance, virulence factor production, and intestinal colonization. among the six rnd efflux systems, vexab exhibited broad substrate specificity and played a predominant role in intrinsic antimicrobial resistance. the vexab system was encoded in an apparent three gene operon that included vexr; which encodes an uncharacterized tetr family regulator. in this work we examined the role ... | 2015 | 25695834 |
| isolation of new delhi metallo-β-lactamase 1-producing vibrio cholerae non-o1, non-o139 strain carrying ctxa, st and hly genes in southern vietnam. | vibrio cholerae non-o1, non-o139 (vc_nag) organisms are universally present in the aquatic environment and regarded as non-pathogenic bacteria. however, considering that they do occasionally induce gastroenteritis, a study of their virulence and antibiotic resistance genes is important. the presence of enteropathogenic genes, including ctxa, vc_nag-specific heat-stable toxin gene (st), hemolysin (hly), and zona occludens toxin (zot) was determined by pcr in 100 vc_nag strains isolated in souther ... | 2015 | 25683557 |
| microcystin-producing and non-producing cyanobacterial blooms collected from the central india harbor potentially pathogenic vibrio cholerae. | on the basis of relative abundance, frequency and biovolume, the important value index ranks were assigned to individual cyanobacteria in phytoplankton samples collected from fourteen water resources of central india. the mcyabde genes were detected in all the blooms with microcystis (-aeruginosa, -viridis, -panniformis, -botrys) as being the major constituent morphospecies. on the other hand, blooms composed of primarily oscillatoria (-limosa,-agardhii, -laetevirens) along with anabaena, nostoc ... | 2015 | 25682583 |
| rna-seq analysis identifies new genes regulated by the histone-like nucleoid structuring protein (h-ns) affecting vibrio cholerae virulence, stress response and chemotaxis. | the histone-like nucleoid structuring protein (h-ns) functions as a transcriptional silencer by binding to at-rich sequences at bacterial promoters. however, h-ns repression can be counteracted by other transcription factors in response to environmental changes. the identification of potential toxic factors, the expression of which is prevented by h-ns could facilitate the discovery of new regulatory proteins that may contribute to the emergence of new pathogenic variants by anti-silencing. vibr ... | 2015 | 25679988 |
| synthesis and molecular structure of the 5-methoxycarbonylpentyl α-glycoside of the upstream, terminal moiety of the o-specific polysaccharide of vibrio cholerae o1, serotype inaba. | the trimethylsilyl trifluoromethanesulfonate (tmsotf)-catalyzed reaction of methyl 6-hydroxyhexanoate with 3-o-benzyl-4-(2,4-di-o-acetyl-3-deoxy-l-glycero-tetronamido)-4,6-dideoxy-2-o-levulinoyl-α-d-mannopyranosyl trichloroacetimidate followed by a two-step deprotection (hydrogenolysis over pd/c catalyst and zemplén deacylation, to simultaneously remove the acetyl and levulinoyl groups) gave 5-(methoxycarbonyl)pentyl 4-(3-deoxy-l-glycero-tetronamido)-4,6-dideoxy-α-d-mannopyranoside. the structur ... | 2015 | 25679049 |
| rapid effects of a protective o-polysaccharide-specific monoclonal iga on vibrio cholerae agglutination, motility, and surface morphology. | 2d6 is a dimeric monoclonal immunoglobulin a (iga) specific for the nonreducing terminal residue of ogawa o-polysaccharide (ops) of vibrio cholerae. it was previously demonstrated that 2d6 iga is sufficient to passively protect suckling mice from oral challenge with virulent v. cholerae o395. in this study, we sought to define the mechanism by which 2d6 iga antibody protects the intestinal epithelium from v. cholerae infection. in a mouse ligated-ileal-loop assay, 2d6 iga promoted v. cholerae ag ... | 2015 | 25667263 |
| crystallization of two operator complexes from the vibrio cholerae higba2 toxin-antitoxin module. | the higa2 antitoxin and the higba2 toxin-antitoxin complex from vibrio cholerae were crystallized in complex with their operator box. screening of 22 different dna duplexes led to two crystal forms of higa2 complexes and one crystal form of a higba2 complex. crystals of higa2 in complex with a 17 bp dna duplex belong to space group p3221, with unit-cell parameters a = b = 94.0, c = 123.7 å, and diffract to 2.3 å resolution. the second form corresponding to higa2 in complex with a 19 bp duplex be ... | 2015 | 25664801 |
| expression, purification and preliminary crystallographic analysis of a haem-utilizing protein, hutx, from vibrio cholerae. | vibrio cholerae, the causative agent of cholera, has developed a variety of mechanisms to obtain the limited-availability iron from human hosts. one important method for iron acquisition is through haem-uptake systems. although the transport of haem has been widely studied, the fate of haem once it enters the cytoplasm remains an open question. here, preliminary x-ray crystallographic analysis was performed on hutx, a member of the conserved haem-utilization operon from v. cholerae strain n16961 ... | 2015 | 25664785 |
| stepwise changes in viable but nonculturable vibrio cholerae cells. | many bacterial species are known to become viable but nonculturable (vbnc) under conditions that are unsuitable for growth. in this study, the requirements for resuscitation of vbnc-state vibrio cholerae cells were found to change over time. although vbnc cells could initially be converted to culturable by treatment with catalase or ht-29 cell extract, they subsequently entered a state that was not convertible to culturable by these factors. however, fluorescence microscopy revealed the presence ... | 2015 | 25664673 |
| transfer activation of sxt/r391 integrative and conjugative elements: unraveling the setcd regulon. | integrative and conjugative elements (ices) of the sxt/r391 family have been recognized as key drivers of antibiotic resistance dissemination in the seventh-pandemic lineage of vibrio cholerae. sxt/r391 ices propagate by conjugation and integrate site-specifically into the chromosome of a wide range of environmental and clinical gammaproteobacteria. sxt/r391 ices bear setc and setd, two conserved genes coding for a transcriptional activator complex that is essential for activation of conjugative ... | 2015 | 25662215 |
| survival, induction and resuscitation of vibrio cholerae from the viable but non-culturable state in the southern caribbean sea. | the causative agent of cholera, vibrio cholerae, can enter into a viable but non-culturable (vbnc) state in response to unfavorable conditions. the aim of this study was to evaluate the in situ survival of v. cholerae in an aquatic environment of the southern caribbean sea, and its induction and resuscitation from the vbnc state. v. cholerae non-o1, non-o139 was inoculated into diffusion chambers placed at the cuare wildlife refuge, venezuela, and monitored for plate, total and viable cells coun ... | 2017 | 25651322 |
| modulating vibrio cholerae quorum-sensing-controlled communication using autoinducer-loaded nanoparticles. | the rise of bacterial antibiotic resistance has created a demand for alternatives to traditional antibiotics. attractive possibilities include pro- and anti-quorum sensing therapies that function by modulating bacterial chemical communication circuits. we report the use of flash nanoprecipitation to deliver the vibrio cholerae quorum-sensing signal cai-1 ((s)-3-hydroxytridecan-4-one) in a water dispersible form as nanoparticles. the particles activate v. cholerae quorum-sensing responses 5 order ... | 2015 | 25651002 |
| anethole inhibits growth of recently emerged multidrug resistant toxigenic vibrio cholerae o1 el tor variant strains in vitro. | to search natural compounds having inhibitory effect on bacterial growth is important, particularly in view of growing multidrug resistant (mdr) strains of bacterial pathogens. like other bacterial pathogens, mdr vibrio cholerae, the causative agent of diarrheal disease cholera, is becoming a great concern. as an approach of searching new antimicrobial agents, here, we show that anethole, a well-studied natural component of sweet fennel and star anise seeds, could potentially inhibit the growth ... | 2015 | 25648987 |
| identification and characterization of vpsr and vpst binding sites in vibrio cholerae. | the ability to form biofilms is critical for environmental survival and transmission of vibrio cholerae, a facultative human pathogen responsible for the disease cholera. biofilm formation is controlled by several transcriptional regulators and alternative sigma factors. in this study, we report that the two main positive regulators of biofilm formation, vpsr and vpst, bind to nonoverlapping target sequences in the regulatory region of vpsl in vitro. vpsr binds to a proximal site (the r1 box) as ... | 2015 | 25622616 |
| intestinal gps: bile and bicarbonate control cyclic di-gmp to provide vibrio cholerae spatial cues within the small intestine. | the second messenger cyclic di-gmp (c-di-gmp) regulates numerous phenotypes in response to environmental stimuli to enable bacteria to transition between different lifestyles. here we discuss our recent findings that the human pathogen vibrio cholerae recognizes 2 host-specific signals, bile and bicarbonate, to regulate intracellular c-di-gmp. we have demonstrated that bile acids increase intracellular c-di-gmp to promote biofilm formation. we have also shown that this bile-mediated increase of ... | 2014 | 25621620 |
| single-molecule tracking and super-resolution imaging shed light on cholera toxin transcription activation. | because of their small size, bacterial cells have long kept details about their inner workings a secret. we are starting to decipher their mechanistic secrets, in no small part due to the development of single-molecule and super-resolution fluorescence imaging, the subject of the 2014 nobel prize in chemistry. these new methods have yielded a surge of discoveries about the subcellular organization and dynamics inside microbes. one example is an increased understanding of the virulence pathway wi ... | 2015 | 25620046 |
| o serogroup-specific touchdown-multiplex polymerase chain reaction for detection and identification of vibrio cholerae o1, o139, and non-o1/non-o139. | a novel, sensitive locus-specific touchdown-multiplex polymerase chain reaction (tmpcr), which is based on two-stage amplification pertaining to multiplex pcr and conditional touchdown strategy, was used in detecting and differentiating vibrio cholerae serogroups. a panel of molecular marker-based tmpcr method generates reproducible profiles of v. cholerae-specific (588 bp) amplicons derived from ompw gene encoding the outer membrane protein and serogroup-specific amplicons, 364 bp for the o1 an ... | 2014 | 25614837 |
| survival and proliferation of the lysogenic bacteriophage ctxφ in vibrio cholerae. | the lysogenic phage ctxφ of vibrio cholerae can transfer the cholera toxin gene both horizontally (inter-strain) and vertically (cell proliferation). due to its diversity in form and species, the complexity of regulatory mechanisms, and the important role of the infection mechanism in the production of new virulent strains of v. cholerae, the study of the lysogenic phage ctxφ has attracted much attention. based on the progress of current research, the genomic features and their arrangement, the ... | 2015 | 25613689 |
| cholera in travelers: shifting tides in epidemiology, management, and prevention. | the distribution of cholera's devastating effects has changed. while cholera is endemic in 50 countries mostly in asia and africa, more than half of the cases reported in 2012 were in the western hemisphere, predominantly haiti. since the current epidemic began in haiti in 2010, there has been spread to the dominican republic, cuba, and most recently mexico. several recent case reports document individuals returning home from affected areas with diarrhea from cholera, in some cases severe. hopef ... | 2015 | 25604481 |
| extracellular matrix structure governs invasion resistance in bacterial biofilms. | many bacteria are highly adapted for life in communities, or biofilms. a defining feature of biofilms is the production of extracellular matrix that binds cells together. the biofilm matrix provides numerous fitness benefits, including protection from environmental stresses and enhanced nutrient availability. here we investigate defense against biofilm invasion using the model bacterium vibrio cholerae. we demonstrate that immotile cells, including those identical to the biofilm resident strain, ... | 2015 | 25603396 |
| clinical manifestations of non-o1 vibrio cholerae infections. | infections caused by non-o1 vibrio cholera are uncommon. the aim of our study was to investigate the clinical and microbiological characteristics of patients with non-o1 v. cholera infections. | 2015 | 25602257 |
| differential specificity of selective culture media for enumeration of pathogenic vibrios: advantages and limitations of multi-plating methods. | plating environmental samples on vibrio-selective chromogenic media is a commonly used technique that allows one to quickly estimate concentrations of putative vibrio pathogens or to isolate them for further study. although this approach is convenient, its usefulness depends directly on how well the procedure selects against false positives. we tested whether a chromogenic medium, chromagar vibrio (cav), used alone (single-plating) or in combination (double-plating) with a traditional medium thi ... | 2015 | 25602161 |
| sequence tag-based analysis of microbial population dynamics. | we describe sequence tag-based analysis of microbial populations (stamp) for characterization of pathogen population dynamics during infection. stamp analyzes the frequency changes of genetically 'barcoded' organisms to quantify population bottlenecks and infer the founding population size. analyses of intraintestinal vibrio cholerae revealed infection-stage and region-specific host barriers to infection and showed unexpected v. cholerae migration counter to intestinal flow. stamp provides a rob ... | 2015 | 25599549 |
| comparison between single dose azithromycin and six doses, 3 day norfloxacin for treatment of cholera in adult. | to evaluate the efficacy of single dose azithromycin (1 gram) in treatment of cholera in adults. a randomized, controlled clinical trial on 120 adults with acute watery diarrhoea and moderate to severe dehydration compared the efficacy of azithromycin (1 gram) single dose and norfloxacin (400 mg) twice daily for three days in treating cholera. data were analysed for 64 patients who were stool culture positive for vibrio cholerae. in conjunction with rehydration therapy, 32 patients received azit ... | 2014 | 25598755 |
| failure of the public health testing program for ballast water treatment systems. | since 2004, an international testing program has certified 53 shipboard treatment systems as meeting ballast water discharge standards, including limits on certain microbes to prevent the spread of human pathogens. we determined how frequently certification tests failed a minimum requirement for a meaningful evaluation, that the concentration of microbes in the untreated (control) discharge must exceed the regulatory limit for treated discharges. in 95% of cases where the result was accepted as ... | 2015 | 25596892 |
| transcript changes in vibrio cholerae in response to salt stress. | vibrio cholerae, which is a serious human intestinal pathogen, often resides and thrives in estuaries but requires major self-regulation to overcome intestinal hyperosmotic stress or high salt stress in water and food. in the present study, we selected multiple o1 and o139 group v. cholerae strains that were isolated from different regions and during different years to study their salt tolerance. based on the mechanisms that other bacteria use to respond to high salt stress, we selected salt str ... | 2014 | 25589902 |
| phenotypic and genetic characterization of vibrio cholerae o1 isolated from various regions of kenya between 2007 and 2010. | cholera, a disease caused by vibrio cholerae o1 and o139 remains an important public health problem globally. in the last decade, kenya has experienced a steady increase of cholera cases. in 2009 alone, 11,769 cases were reported to the ministry of public health and sanitation. this study sought to describe the phenotypic characteristics of the isolated v. cholerae isolates. | 2014 | 25584121 |
| polymyxin b resistance and biofilm formation in vibrio cholerae are controlled by the response regulator carr. | two-component systems play important roles in the physiology of many bacterial pathogens. vibrio cholerae's carrs two-component regulatory system negatively regulates expression of vps (vibrio polysaccharide) genes and biofilm formation. in this study, we report that carr confers polymyxin b resistance by positively regulating expression of the almefg genes, whose products are required for glycine and diglycine modification of lipid a. we determined that carr directly binds to the regulatory reg ... | 2015 | 25583523 |
| drinking cholera: salinity levels and palatability of drinking water in coastal bangladesh. | to measure the salinity levels of common water sources in coastal bangladesh and explore perceptions of water palatability among the local population to investigate the plausibility of linking cholera outbreaks in bangladesh with ingestion of saline-rich cholera-infected river water. | 2015 | 25581714 |
| [microevolution of cholera agent in the modern period]. | to carry out comparative molecular genetic analysis of highly pathogenic atypical vibrio cholerae strains biovar el tor, isolated in the territory of rf, in order to determine micro-evolutionary alterations of cholera agent in the modern period. | 2014 | 25563004 |
| a metalloprotease secreted by the type ii secretion system links vibrio cholerae with collagen. | vibrio cholerae is autochthonous to various aquatic niches and is the etiological agent of the life-threatening diarrheal disease cholera. the persistence of v. cholerae in natural habitats is a crucial factor in the epidemiology of cholera. in contrast to the well-studied v. cholerae-chitin connection, scarce information is available about the factors employed by the bacteria for the interaction with collagens. collagens might serve as biologically relevant substrates, because they are the most ... | 2015 | 25561716 |
| vibrio cholerae represses polysaccharide synthesis to promote motility in mucosa. | the viscoelastic mucus layer of gastrointestinal tracts is a host defense barrier that a successful enteric pathogen, such as vibrio cholerae, must circumvent. v. cholerae, the causative agent of cholera, is able to penetrate the mucosa and colonize the epithelial surface of the small intestine. in this study, we found that mucin, the major component of mucus, promoted v. cholerae movement on semisolid medium and in liquid medium. a genome-wide screen revealed that vibrio polysaccharide (vps) pr ... | 2015 | 25561707 |
| comparative proteomic analysis reveals activation of mucosal innate immune signaling pathways during cholera. | vibrio cholerae o1 is a major cause of acute watery diarrhea in over 50 countries. evidence suggests that v. cholerae o1 may activate inflammatory pathways, and a recent study of a bangladeshi population showed that variants in innate immune genes play a role in mediating susceptibility to cholera. we analyzed human proteins present in the small intestine of patients infected with v. cholerae o1 to characterize the host response to this pathogen. we collected duodenal biopsy specimens from patie ... | 2015 | 25561705 |
| non-o1/non-o139 vibrio cholerae carrying multiple virulence factors and v. cholerae o1 in the chesapeake bay, maryland. | non-o1/non-o139 vibrio cholerae inhabits estuarine and coastal waters globally, but its clinical significance has not been sufficiently investigated, despite the fact that it has been associated with septicemia and gastroenteritis. the emergence of virulent non-o1/non-o139 v. cholerae is consistent with the recognition of new pathogenic variants worldwide. oyster, sediment, and water samples were collected during a vibrio surveillance program carried out from 2009 to 2012 in the chesapeake bay, ... | 2015 | 25556194 |
| the type vi secretion system of vibrio cholerae fosters horizontal gene transfer. | natural competence for transformation is a common mode of horizontal gene transfer and contributes to bacterial evolution. transformation occurs through the uptake of external dna and its integration into the genome. here we show that the type vi secretion system (t6ss), which serves as a predatory killing device, is part of the competence regulon in the naturally transformable pathogen vibrio cholerae. the t6ss-encoding gene cluster is under the positive control of the competence regulators tfo ... | 2015 | 25554784 |
| urinary tract infection due to nono1 vibrio cholerae. | | 2016 | 25553995 |
| vibrio cholerae ghosts (vcg) exert immunomodulatory effect on dendritic cells for enhanced antigen presentation and induction of protective immunity. | we previously showed that the vibrio cholerae ghost platform (vcg; empty v. cholerae cell envelopes) is an effective delivery system for vaccine antigens promoting the induction of substantial immunity in the absence of external adjuvants. however, the mechanism by which these cell envelopes enhance immunity and stimulate a predominantly th1 cellular and humoral immune response has not been elucidated. we hypothesized that the immunostimulatory ability of vcg involves dendritic cell (dc) activat ... | 2014 | 25551828 |
| the vibrio cholerae toxr regulon encodes host-specific chemotaxis proteins that function in intestinal colonization. | virulence gene regulation in vibrio cholerae is under the control of the toxr-toxt regulatory cascade. chemotaxis and net motility have been shown to influence the infectivity of vibrio cholerae. v. cholerae toxr mutants do not synthesize proteins required for chemotaxis towards mucus. the inability of the toxr mutant strain to recognize and swim towards mucus is due to their failure to synthesize acfb, a methyl-accepting chemotaxis protein. acfb has previously been shown to be involved in intes ... | 2017 | 27213179 |
| withdrawn: novel role of leuo in hns mediated silencing of the vibrio cholerae virulence regulatory gene toxt. | this manuscript has been withdrawn by the author. | 2014 | 25548286 |
| novel readout method for molecular diagnostic assays based on optical measurements of magnetic nanobead dynamics. | we demonstrate detection of dna coils formed from a vibrio cholerae dna target at picomolar concentrations using a novel optomagnetic approach exploiting the dynamic behavior and optical anisotropy of magnetic nanobead (mnb) assemblies. we establish that the complex second harmonic optical transmission spectra of mnb suspensions measured upon application of a weak uniaxial ac magnetic field correlate well with the rotation dynamics of the individual mnbs. adding a target analyte to the solution ... | 2015 | 25539065 |
| phylodynamic analysis of clinical and environmental vibrio cholerae isolates from haiti reveals diversification driven by positive selection. | phylodynamic analysis of genome-wide single-nucleotide polymorphism (snp) data is a powerful tool to investigate underlying evolutionary processes of bacterial epidemics. the method was applied to investigate a collection of 65 clinical and environmental isolates of vibrio cholerae from haiti collected between 2010 and 2012. characterization of isolates recovered from environmental samples identified a total of four toxigenic v. cholerae o1 isolates, four non-o1/o139 isolates, and a novel nontox ... | 2014 | 25538191 |
| [sensitivity to antibacterial preparations of vibrio cholerae el tor strains isolated from the environmental objects in russia in 2005 - 2012]. | analysis of antibiotic resistance profiles of vibrio cholerae o1 strains isolated from the environmental objects in the territory of russia in 2005 - 2012. | 2014 | 25536777 |
| inca/c plasmids harboured in serious multidrug-resistant vibrio cholerae serogroup o139 strains in china. | vibrio cholerae serogroup o139 emerged in 1992 and is one of two major serogroups to have caused cholera epidemics. after 1998, serious multidrug-resistant (mdr) o139 strains quickly became common in china, showing a multidrug resistance profile to eight antibiotics. it is a great threat to public health, and elucidation of its mechanisms of resistance will provide a helpful guide for the clinical treatment and prevention of cholera. in this study, mega-plasmids from mdr v. cholerae o139 strains ... | 2015 | 25532743 |
| monitoring water sources for environmental reservoirs of toxigenic vibrio cholerae o1, haiti. | | 2015 | 25531032 |
| the acetate switch of an intestinal pathogen disrupts host insulin signaling and lipid metabolism. | vibrio cholerae is lethal to the model host drosophila melanogaster through mechanisms not solely attributable to cholera toxin. to examine additional virulence determinants, we performed a genetic screen in v. cholerae-infected drosophila and identified the two-component system crbrs. crbrs controls transcriptional activation of acetyl-coa synthase-1 (acs-1) and thus regulates the acetate switch, in which bacteria transition from excretion to assimilation of environmental acetate. the resultant ... | 2014 | 25525791 |
| dynamic intervention: pathogen disarmament of mitochondrial-based immune surveillance. | in this issue of cell host & microbe, suzuki et al. (2014) describe a vibrio cholerae type-iii-secreted effector that targets mitochondrial dynamics to dampen host innate immune signaling. this suggests that mammalian hosts possess surveillance mechanisms to monitor pathogen-mediated alterations in the integrity of normal cellular processes and organelles. | 2014 | 25525786 |
| microbiota talks cholera out of the gut. | in a recent nature paper, hsiao et al., 2014 examine microbiota contribution during and after cholera and identify commensals correlated with healing and reconstitution of the microbial community. one particular species may use intercellular communication to stymie vibrio cholerae pathogenesis, indicating how the microbiota can restrict pathogens. | 2014 | 25525783 |
| solar-photocatalytic disinfection of vibrio cholerae by using ag@zno core-shell structure nanocomposites. | disinfection of gram-negative bacterium vibrio cholerae 569b in aqueous matrix by solar-photocatalysis mediated by ag@zno core-shell structure nanocomposite particles was investigated. silver nanoparticles are synthesized by the reduction of silver perchlorate followed by precipitation of zinc oxide shell and are employed in the photocatalytic disinfection of the model pathogen. effect of photocatalyst loading and reaction temperature on the disinfection kinetics was studied. disinfection effici ... | 2015 | 25523714 |
| in vitro and in vivo antimicrobial efficacy of natural plant-derived compounds against vibrio cholerae of o1 el tor inaba serotype. | in this study, we investigated antibacterial activities of 20 plant-derived natural compounds against gram-negative enteric pathogens. we found that both flavonoids and non-flavonoids, including honokiol and magnolol, possess specific antibacterial activities against v. cholerae, but not against other species of gram-negative bacterium which we tested. using various antibacterial assays, we determined that there was a dose-dependent bactericidal and biofilm inhibitory activity of honokiol and ma ... | 2015 | 25516242 |
| mechanistic insights into filamentous phage integration in vibrio cholerae. | vibrio cholerae, the etiological agent of acute diarrhoeal disease cholera, harbors large numbers of lysogenic filamentous phages, contribute significantly to the host pathogenesis and provide fitness factors to the pathogen that help the bacterium to survive in natural environment. most of the vibriophage genomes are not equipped with integrase and thus exploit two host-encoded tyrosine recombinases, xerc and xerd, for lysogenic conversion. integration is site-specific and it occurs at dimer re ... | 2014 | 25506341 |
| a study on the existence of vibrio cholerae non-o1 in the river. | the aim of the present study is vibrio cholerae non-o1 existing in river. bacteria are known to inhabit all kinds of environment. vibrionaceae is widely distributed in environmental water. vibrio spp. have been identified as a cause of toxicity in fish and shellfish. one condition affecting the survival of pathogenic microorganisms in environmental water is the salt concentration, and they have been reported to inhabit brackish water. however, v. cholerae non-o1 has also been detected in fresh w ... | 2015 | 25500964 |
| detection of vibrio cholerae o1 and o139 in environmental waters of rural bangladesh: a flow-cytometry-based field trial. | presence of vibrio cholerae serogroups o1 and o139 in the waters of the rural area of matlab, bangladesh, was investigated with quantitative measurements performed with a portable flow cytometer. the relevance of this work relates to the testing of a field-adapted measurement protocol that might prove useful for cholera epidemic surveillance and for validation of mathematical models. water samples were collected from different water bodies that constitute the hydrological system of the region, a ... | 2015 | 25496520 |
| turn-on optomagnetic bacterial dna sequence detection using volume-amplified magnetic nanobeads. | detection of a vibrio cholerae dna-sequence using an optomagnetic read-out exploiting the dynamic behavior of magnetic nanobeads along with two turn-on data analysis approaches is demonstrated. the optomagnetic method uses a weak uniaxial ac magnetic field of varying frequency applied perpendicular to the optical path and measures the modulation of laser light passing through a cuvette containing the sample with oligonucleotide-tagged magnetic beads and macromolecular coils of single-stranded dn ... | 2015 | 25483917 |
| development of benzo[1,4]oxazines as biofilm inhibitors and dispersal agents against vibrio cholerae. | bacterial biofilms are estimated to be associated with over 65 percent of all nosocomial infections. however, no therapeutics have been approved by the fda which directly mediate biofilm formation or persistence. herein we report oxazine as a highly potent inhibitor, disperser and in the presence of the appropriate antibiotic eradicator of v. cholerae biofilms. | 2015 | 25479128 |
| lolb gene, a valid alternative for qpcr detection of vibrio cholerae in food and environmental samples. | in recent years a new genetic target for vibrio cholerae detection has been reported, but its application was limited to clinical samples. this target, lolb, has never been applied to either food or environmental samples. in the present study the development, as well as the evaluation and pre-validation, of a real-time pcr method based on lolb, is described. the method included a newly designed hydrolysis probe to enhance its specificity. after comparison against other molecular and traditional ... | 2015 | 25475326 |
| immunizing adult female mice with a tcpa-a2-ctb chimera provides a high level of protection for their pups in the infant mouse model of cholera. | vibrio cholerae expresses two primary virulence factors, cholera toxin (ct) and the toxin-coregulated pilus (tcp). ct causes profuse watery diarrhea, and tcp (composed of repeating copies of the major pilin tcpa) is required for intestinal colonization by v. cholerae. antibodies to ct or tcpa can protect against cholera in animal models. we developed a tcpa holotoxin-like chimera (tcpa-a2-ctb) to elicit both anti-tcpa and anti-ctb antibodies and evaluated its immunogenicity and protective effica ... | 2014 | 25474636 |
| glucose- but not rice-based oral rehydration therapy enhances the production of virulence determinants in the human pathogen vibrio cholerae. | despite major attempts to prevent cholera transmission, millions of people worldwide still must address this devastating disease. cholera research has so far mainly focused on the causative agent, the bacterium vibrio cholerae, or on disease treatment, but rarely were results from both fields interconnected. indeed, the treatment of this severe diarrheal disease is mostly accomplished by oral rehydration therapy (ort), whereby water and electrolytes are replenished. commonly distributed oral reh ... | 2014 | 25474211 |
| crystal structure of the bacterial type vi secretion system component tssl from vibrio cholerae. | the type vi secretion system (t6ss), commonly found in gram-negative bacteria, is responsible for exporting effector proteins. the t6ss has been reported to be cytotoxic to host cells. while the components and assembly of the t6ss complex have been largely assessed, structural data on t6ss components from virulent bacteria is remarkably insufficient. here, we report the crystal structure of vibrio cholerae tssl (vctssl), a core component of t6ss. in spite of a relatively low sequence identity, t ... | 2015 | 25471186 |
| can chatter between microbes prevent cholera? | tackling the global rise in antibiotic resistance requires new therapies against infectious microbes. a recent microbiome study identified commensal gut bacteria that reduce colonisation by the cholera pathogen, vibrio cholerae. this antagonistic interaction might be mediated by quorum sensing, suggesting that these natural microbe-microbe interactions can help prevent infectious disease. | 2014 | 25468792 |
| vca1008: an anion-selective porin of vibrio cholerae. | a putative porin function has been assigned to vca1008 of vibrio cholerae. its coding gene, vca1008, is expressed upon colonization of the small intestine in infant mice and human volunteers, and is essential for infection. in vitro, vca1008 is expressed under inorganic phosphate limitation and, in this condition, vca1008 is the major outer membrane protein of the bacterium. here, we provide the first functional characterization of vca1008 reconstituted into planar lipid bilayers. our main findi ... | 2015 | 25462170 |
| pentavalent outer membrane vesicles of vibrio cholerae induce adaptive immune response and protective efficacy in both adult and passive suckling mice models. | recently, we demonstrated oral immunizations with single serotype outer membrane vesicles of vibrio cholerae induced serogroup specific protective immunity in the ritard model. in our present study, we advanced our research by formulating multi-serotype outer membrane vesicles, mixing the omvs of five virulent v. cholerae strains. four doses of oral immunization with cholera pentavalent outer membrane vesicles (cpmvs) induced v. cholerae specific b and t cell responses. cpmvs-immunized mice gene ... | 2015 | 25461799 |
| management of multipartite genomes: the vibrio cholerae model. | a minority of bacterial species has been found to carry a genome divided among several chromosomes. among these, all vibrio species harbor a genome split into two chromosomes of uneven size, with distinctive replication origins whose replication firing involves common and specific factors. most of our current knowledge on replication and segregation in multi-chromosome bacteria has come from the study of vibrio cholerae, which is now the model organism for this field. it has been firmly establis ... | 2014 | 25460805 |
| vibrio cholerae t3ss effector vope modulates mitochondrial dynamics and innate immune signaling by targeting miro gtpases. | the cellular surveillance-activated detoxification and defenses (csadd) theory postulates the presence of host surveillance mechanisms that monitor the integrity of common cellular processes and components targeted by pathogen effectors. being organelles essential for multiple cellular processes, including innate immune responses, mitochondria represent an attractive target for pathogens. we describe a vibrio cholerae type 3 secretion system effector vope that localizes to mitochondria during in ... | 2014 | 25450857 |
| crystal structure of hlyu, the hemolysin gene transcription activator, from vibrio cholerae n16961 and functional implications. | hlyu in vibrio cholerae is known to be the transcriptional activator of the hemolysin gene, hlya and possibly a regulator of other virulence factors influencing growth, colonization and pathogenicity of this infective agent. here we report the crystal structure of hlyu from v. cholerae n16961 (hlyu_vc) at 1.8å. the protein, with five α-helices and three β-strands in the topology of α1-α2-β1-α3-α4-β2-β3-α5, forms a homodimer. helices α3-α4 and a β sheet form the winged helix-turn-helix (whth) dna ... | 2014 | 25450504 |
| site-directed spin-labeling strategies and electron paramagnetic resonance spectroscopy for large riboswitches. | genetic regulation effected by rna riboswitches is governed by ligand-induced structural reorganization with modulation of rna conformation and dynamics. characterization of the conformational states of riboswitches in the presence or absence of salts and ligands is important for understanding how interconversion of riboswitch rna folding states influences function. the methodology of site-directed spin labeling (sdsl) coupled with electron paramagnetic resonance (epr) spectroscopy is suitable f ... | 2014 | 25432754 |
| transmembrane oligomeric form of vibrio cholerae cytolysin triggers tlr2/tlr6-dependent proinflammatory responses in monocytes and macrophages. | vibrio cholerae cytolysin (vcc) kills target eukaryotic cells by forming transmembrane oligomeric β-barrel pores. once irreversibly converted into the transmembrane oligomeric form, vcc acquires an unusual structural stability and loses its cytotoxic property. it is therefore possible that, on exertion of its cytotoxic activity, the oligomeric form of vcc retained in the disintegrated membrane fractions of the lysed cells would survive within the host cellular milieu for a long period, without c ... | 2015 | 25431887 |
| vibrio cholerae martx toxin heterologous translocation of beta-lactamase and roles of individual effector domains on cytoskeleton dynamics. | the vibrio cholerae martxvc toxin delivers three effector domains to eukaryotic cells. to study toxin delivery and function of individual domains, the rtxa gene was modified to encode toxin with an in-frame beta-lactamase (bla) fusion. the hybrid rtxa::bla toxin was type i secreted from bacteria; and then bla was translocated into eukaryotic cells and delivered by autoprocessing, demonstrating that the martxvc toxin is capable of heterologous protein transfer. strains that produce hybrid rtxa::b ... | 2015 | 25427654 |
| influence of diffusion on the stability of equilibria in a reaction-diffusion system modeling cholera dynamic. | a reaction-diffusion system modeling cholera epidemic in a non-homogeneously mixed population is introduced. the interaction between population and toxigenic vibrio cholerae concentration in contaminated water has been taken into account. the existence of biologically meaningful equilibria is investigated together with their linear and nonlinear stability. using the data collected during the haiti cholera epidemic, a numerical simulation is performed. | 2015 | 25424418 |
| assessing clonal correlation of epidemic vibrio cholerae isolates during 2011 in 16 provinces of iran. | a total of 1,187 vibrio cholerae isolates were received during 2011 cholera outbreaks from 16 provinces in different geographical location to iranian reference health laboratory. a random selection was performed, and 61 isolates were subjected to further investigations. cholera cases were come up from may with nine cases and reached to its maximum rate at august (57 cases) and continued to october after which a fall occurred in september. all of the isolates were susceptible to three antimicrobi ... | 2015 | 25424344 |
| a small unstructured region in vibrio cholerae toxt mediates the response to positive and negative effectors and toxt proteolysis. | vibrio cholerae is the causative agent of the severe diarrheal disease cholera. the production of the virulence factors that are required for human disease is controlled by a complex network of transcriptional and posttranscriptional regulators. toxt is the transcription regulator that directly controls the production of the two major virulence factors, toxin-coregulated pilus (tcp) and cholera toxin (ct). the solved crystal structure of toxt revealed an unstructured region in the n-terminal dom ... | 2015 | 25422303 |
| protein a-conjugated iron oxide nanoparticles for separation of vibrio cholerae from water samples. | pathogen separation is of great significance for precise detection and prevention of disease outbreaks. for the first time, protein a conjugated with chitosan-coated iron oxide nanoparticles was prepared for pathogen separation at low concentrations from liquid samples. vibrio cholerae o1 (vo1) bacteria were used for testing the effectiveness of this conjugate. transmission electron microscopy (tem) was used to confirm the presence of captured vo1. the results showed that, after binding with a s ... | 2014 | 25421572 |
| chironomid microbiome. | chironomids are abundant insects in freshwater habitats. they undergo a complete metamorphosis of four life stages: eggs, larvae, and pupae in water, and a terrestrial adult stage. chironomids are known to be pollution-tolerant, but little is known about their resistance mechanisms to toxic substances. here we review current knowledge regarding the chironomid microbiome. chironomids were found as natural reservoirs of vibrio cholerae and aeromonas spp. a stable bacterial community was found in t ... | 2015 | 25421389 |
| hypoxia-induced localization of chemotaxis-related signaling proteins in vibrio cholerae. | vibrio cholerae has three sets of chemotaxis-related signaling proteins, of which only system ii has been shown to be involved in chemotaxis. here, we examined localization of green fluorescent protein (gfp)-fused components of system i. the histidine kinase (chea1) and the adaptor (chew0) of system i localized to polar and lateral membrane regions with standing incubation (microaerobic conditions), but their localization was lost after shaking (aerobic conditions). a transmembrane receptor of s ... | 2015 | 25420689 |
| molecular determinants of mechanical properties of v. cholerae biofilms at the air-liquid interface. | biofilm formation increases both the survival and infectivity of vibrio cholerae, the causative agent of cholera. v. cholerae is capable of forming biofilms on solid surfaces and at the air-liquid interface, termed pellicles. known components of the extracellular matrix include the matrix proteins bap1, rbma, and rbmc, an exopolysaccharide termed vibrio polysaccharide, and dna. in this work, we examined a rugose strain of v. cholerae and its mutants unable to produce matrix proteins by interfaci ... | 2014 | 25418293 |
| genetic traits of vibrio cholerae o1 haitian isolates that are absent in contemporary strains from kolkata, india. | the world's worst cholera epidemic in haiti (2010) coerced to trace the origin and dissemination of the causative agent vibrio cholerae o1 for proper management of cholera. sequence analysis of the haitian strain showed several variations in the genes encoding cholera toxin b subunit (ctxb); toxin-co-regulated pilus (tcpa), repeat in toxins (rtxa), quinolone resistance-determining region (qrdr) of gyrase a (gyra), rstb of rs element along with the change in the number of repeat sequences at the ... | 2014 | 25415339 |
| household transmission of vibrio cholerae in bangladesh. | vibrio cholerae infections cluster in households. this study's objective was to quantify the relative contribution of direct, within-household exposure (for example, via contamination of household food, water, or surfaces) to endemic cholera transmission. quantifying the relative contribution of direct exposure is important for planning effective prevention and control measures. | 2014 | 25411971 |
| crystal structure of apo and ligand bound vibrio cholerae ribokinase (vc-rk): role of monovalent cation induced activation and structural flexibility in sugar phosphorylation. | | 2015 | 25408351 |
| vibrio cholerae cytolysin: structure-function mechanism of an atypical β-barrel pore-forming toxin. | | 2015 | 25408339 |