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induction of immune memory by a multisubunit chlamydial vaccine.we tested the hypothesis that intramuscular immunization with a multisubunit chlamydial vaccine candidate will induce long lasting immune responses in mice. accordingly, groups of female c57bl/6 mice were immunized intramuscularly with vibrio cholerae ghosts (vcg) expressing the poring b and polymorphic membrane protein-d proteins of chlamydia trachomatis or a control antigen. humoral and cell-mediated immune responses were evaluated following immunization and after live chlamydial infection. im ...201021184858
effect of neem extract against the bacteria isolated from marine fish.marine ornamental fishes are exceedingly valuable due to their high demand in domestic and international markets. there is a growing global interest to rear the fishes in captivity. but problem due to bacteria and fungi are the major hitch in captive condition. since, the use of antibiotics is banned, an attempt was made to ascertain in vitro assay of the neem leaves extract against the bacterial pathogens isolated from infected fishes. bacterial strains isolated from infected regions of the clo ...201021186711
vibrio cholerae o1 infection in taiwan. 201021187112
vibrio cholerae anaerobic induction of virulence gene expression is controlled by thiol-based switches of virulence regulator aphb.bacterial pathogens have evolved sophisticated signal transduction systems to coordinately control the expression of virulence determinants. for example, the human pathogen vibrio cholerae is able to respond to host environmental signals by activating transcriptional regulatory cascades. the host signals that stimulate v. cholerae virulence gene expression, however, are still poorly understood. previous proteomic studies indicated that the ambient oxygen concentration plays a role in v. cholerae ...201021187377
[development of multiplex real time pcr methodology for better identification and discrimination of vibrio cholerae and o139 serotype.]objective: to develop a rapid, sensitive and specific assay method, based on multiplex real time pcr for identifying vibrio cholerae and distinguishing vibrio cholerae o139 serotype from vibrio cholerae. methods: cholera toxin a subunit gene (ctxa) and glycosyltransferase gene (lpsgt) were chosen as targets according to vibrio cholerae and vibrio cholerae o139 serotype, and then the primers and taqman-mgb probe were designed. the 5'end of probes was labeled with fam and vic fluoresceins respecti ...201021162870
[outbreak of cholera associated with consumption of soft-shelled turtles, sichuan province, china, 2009.]objective: vibrio cholera was extremely rare in sichuan province(no cases in 2008). any outbreak could indicate contamination through the food supply system. in july 2009, a hospital reported a cluster of 7 diarrhea patients;all attended the same banquet. one patient was confirmed to have vibrio cholera (o139). we conducted this investigation to identify the source of this possible cholera outbreak. methods: we defined a suspect case as any banquet attendee with diarrhea (≥ 3 times/day). a confi ...201021162875
replication patterns and organization of replication forks in vibrio cholerae.we have investigated the replication patterns of the two chromosomes of the bacterium vibrio cholerae grown in four different media. by combining flow cytometry and quantitative real-time pcr with computer simulations, we show that in rich media, v. cholerae cells grow with overlapping replication cycles of both the large chromosome (chri) and the small chromosome (chrii). in luria-bertani (lb) medium, initiation occurs at four copies of the chri origin and two copies of the chrii origin. replic ...201021163839
h-ns binding and repression of the ctx promoter in vibrio cholerae.expression of the ctx and tcp genes, which encode cholera toxin and the toxin coregulated pilus, the vibrio cholerae o1 virulence determinants having the largest contribution to cholera disease, is repressed by the nucleoid-associated protein h-ns and activated by the arac-like transcriptional regulator toxt. to elucidate the molecular mechanism by which h-ns controls transcription of the ctxab operon, h-ns repression and binding were characterized by using a promoter truncation series, gel mobi ...201021169492
cholera- and anthrax-like toxins are among several new adp-ribosyltransferases.chelt, a cholera-like toxin from vibrio cholerae, and certhrax, an anthrax-like toxin from bacillus cereus, are among six new bacterial protein toxins we identified and characterized using in silico and cell-based techniques. we also uncovered medically relevant toxins from mycobacterium avium and enterococcus faecalis. we found agriculturally relevant toxins in photorhabdus luminescens and vibrio splendidus. these toxins belong to the adp-ribosyltransferase family that has conserved structure d ...201021170356
in silico prediction of drug targets in vibrio cholerae.identification of potential drug targets is the first step in the process of modern drug discovery, subjected to their validation and drug development. whole genome sequences of a number of organisms allow prediction of potential drug targets using sequence comparison approaches. here, we present a subtractive approach exploiting the knowledge of global gene expression along with sequence comparisons to predict the potential drug targets more efficiently. based on the knowledge of 155 known viru ...201021174131
update on cholera --- haiti, dominican republic, and florida, 2010.on october 21, 2010, a cholera outbreak was confirmed by the haitian national public health laboratory. by november 19, the outbreak had reached every department of the country, and by december 17, a total of 121,518 cases of cholera, resulting in 63,711 hospitalizations and 2,591 deaths, had been reported. by november 16, additional cases of cholera had been confirmed in the neighboring dominican republic and in florida. several confirmed cases in the dominican republic and all confirmed u.s. c ...201021178947
synthesis and antimicrobial activity of some new n-substituted quinoline derivatives of 1h-pyrazole.a new series of 32 derivatives of 4-pyrazolyl-n-(hetero)arylquinoline 5a-p and 6a-p were synthesized by a one-pot base-catalyzed cyclocondensation reaction of 1-phenyl-3-(hetero)aryl-pyrazole-4-carbaldehyde 1a-h, malononitrile 2, and 3-(hetero)aryl-5,5-disubstitutedcyclohex-2-enone 3a-b or 4a-b, respectively. all the synthesized compounds were characterized by elemental analysis, ft-ir, (1)h-nmr, and (13)c-nmr spectral data. all the synthesized compounds were screened, against six bacterial path ...201021181734
a dominant-negative approach that prevents diphthamide formation confers resistance to pseudomonas exotoxin a and diphtheria toxin.diphtheria toxin (dt), pseudomonas aeruginosa exotoxin a (eta) and cholix toxin from vibrio cholerae share the same mechanism of toxicity; these enzymes adp-rybosylate elongation factor-2 (ef-2) on a modified histidine residue called diphthamide, leading to a block in protein synthesis. mutant chinese hamster ovary cells that are defective in the formation of diphthamide have no distinct phenotype except their resistance to dt and eta. these observations led us to predict that a strategy that pr ...201021203470
structure of the o-polysaccharide of vibriocholerae o43 containing a new monosaccharide derivative, 4-(n-acetyl-l-allothreonyl)amino-4,6-dideoxy-d-glucose.the o-polysaccharide of vibrio cholerae o43 was studied using chemical analyses, triflic acid solvolysis and 2d nmr spectroscopy, including (1)h/(1)h cosy, tocsy, noesy and (1)h/(13)c gradient-selected hsqc experiments. the following structure of the tetrasaccharide repeating unit of the polysaccharide was established: →3)-β-d-quip4nacyl-(1→3)-α-d-galpnaca-(1→4)-α-d-galpnac-(1→3)-α-d-quipnac-(1→ where d-quinac stands for 2-acetamido-2,6-dideoxy-d-glucose, d-qui4nacyl for 4-(n-acetyl-l-allothreon ...201021232736
salmonella enterica serovars typhi and paratyphi a are avirulent in newborn and infant mice even when expressing virulence plasmid genes of salmonella typhimurium.salmonella enterica serovars typhi and paratyphi a are human host-restricted pathogens. therefore, there is no small susceptible animal host that can be used to assess the virulence and safety of vaccine strains derived from these salmonella serovars.  however, infant mice have been used to evaluate virulence and colonization by another human host-restricted pathogen, vibrio cholerae.201021252450
remodelling of the vibrio cholerae membrane by incorporation of exogenous fatty acids from host and aquatic environments.the gram-negative bacteria vibrio cholerae poses significant public health concerns by causing an acute intestinal infection afflicting millions of people each year. v. cholerae motility, as well as virulence factor expression and outer membrane protein production, has been shown to be affected by bile. the current study examines the effects of bile on v. cholerae phospholipids. bile exposure caused significant alterations to the phospholipid profile of v. cholerae but not of other enteric patho ...201021255114
preparation, spectroscopy, exafs, electrochemistry and pharmacology of new ruthenium(ii) carbonyl complexes containing ferrocenylthiosemicarbazone and triphenylphosphine/arsine.a new series of new hetero-bimetallic complexes containing iron and ruthenium of the general formula [rucl(co)(b)(eph3)(l)] (where e=p or as; b=pph3, asph3, py or pip; l=ferrocene derived monobasic bidentate thiosemicarbazone ligand) have been synthesized by the reaction between ferrocene-derived thiosemicarbazones and ruthenium(ii) complexes of the type [ruhcl(co)(b)(eph3)2] (where e=p or as; b=pph3, asph3, py or pip). the new complexes have been characterized by elemental analyses, ir, electro ...201021216187
[molecular subtyping of vibrio cholerae isolates from outbreaks of cholera by pulsed-field gel electrophoresis in hainan in 2008].to analyze the molecular characteristics and genetic correlations of vibrio cholerae islolates in hainan in 2008, so as to provide pathogenic proof to diagnose the plague.201021215108
[epidemic condition and biological characteristics of non-o1/non-o139 vibrio cholerae in haizhu district of guangzhou].to understand the epidemic condition, distribution and biological characteristics of non-o1/non-o139 vibrio cholerae from 2001 to 2009 in haizhu district, to provide a scientific basis for the prevention and control of acute diarrhea.201021215109
a multipathogen selective enrichment broth for simultaneous growth of salmonella spp., vibrio parahaemolyticus, and vibrio cholerae.a selective enrichment broth (svv) was formulated to allow concurrent growth of salmonella spp., v. parahaemolyticus, and v. cholerae. potassium tellurite and sodium citrate were added as the inhibitors, while glucose, mannitol, anhydrous sodium sulfite and sodium pyruvate were employed as the growth-promoters. when mixed in equal or varied proportions, the target pathogens in svv had a great accumulation (10(5)-10(8) cfu/ml) and effectively inhibited the growth of competitive microflora. in the ...201021282902
synthesis, antimicrobial and anticancer activity of new thiosemicarbazone derivatives.thiosemicarbazones of p-aminobenzoic acid (paba) were synthesized and tested for their antimicrobial and anticancer activity. hydroxamate derivatives 4a-4l were found to have better antimicrobial and anticancer activity than their acid counterpart. compound 4d was found to have good antimicrobial activity against escherichia coli, klebsiella pneumoniae, staphylococcus aureus, vibrio cholerae, and bacillus subtilis with ic(50) value of about 1 µm. compound 4f showed potent antifungal activity aga ...201021290424
synthesis and antimicrobial activity of some new n-substituted quinoline derivatives of 1h-pyrazole.a new series of 32 derivatives of 4-pyrazolyl-n-(hetero)arylquinoline 5a-p and 6a-p were synthesized by a one-pot base-catalyzed cyclocondensation reaction of 1-phenyl-3-(hetero)aryl-pyrazole-4-carbaldehyde 1a-h, malononitrile 2, and 3-(hetero)aryl-5,5-disubstitutedcyclohex-2-enone 3a-b or 4a-b, respectively. all the synthesized compounds were characterized by elemental analysis, ft-ir, (1) h-nmr, and (13) c-nmr spectral data. all the synthesized compounds were screened, against six bacterial pa ...201021290425
antibacterial activity of thai medicinal plants pikutbenjakul.bacterial infections caused by resistant strains have been increased dramatically. pikutbenjakul, a thai medicinal plant formula containing piper longum, piper sarmentosum, piper interruptum, plumbago indica and zingiber officinale have been widely used in thai traditional medicine.201021298838
[identification of vibrio cholerae serogroups o1 and o139 by monoclonal antibodies in the slide agglutination test].the agglutinating properties of mca-o1 of the igg class and mca-o139 of the igm class towards epitopes of o-antigen of vibrio cholerae o1 and accordingly vibrio cholerae o139 were studied. the ascitic and cultural fluids by hybridomas f8g12 and d11 deposited in the specialized collection of cell cultures of vertebrates (saint petersburg) under rkkk (ii) 386 d and rkkk (ii) 674 d were the sources of monoclonal immunoglobulins. the advantage of diagnostic monoclonal immunoglobulins is that they ar ...201021313756
mixed infections of vibrio cholerae o1 ogawa el tor with shigella dysenteriae.mixed infections caused by enteric pathogens such as bacteria, virus, protozoa and helminthes were reported in different literatures. this report also describes the co-infections caused by vibrio cholerae o1 ogawa el tor with shigella dysenteriae in a patient. a 36-year-old man was admitted in fatemeh zahra hospital of bushehr iran with fever, vomiting and dysentery. his stool sample was cultured, for identification purposes tcbs, xld and other media were used. v. cholerae and s. dysenteriae wer ...201021313886
infectious diarrhea: cellular and molecular mechanisms.diarrhea caused by enteric infections is a major factor in morbidity and mortality worldwide. an estimated 2-4 billion episodes of infectious diarrhea occur each year and are especially prevalent in infants. this review highlights the cellular and molecular mechanisms underlying diarrhea associated with the three classes of infectious agents, i.e., bacteria, viruses and parasites. several bacterial pathogens have been chosen as model organisms, including vibrio cholerae as a classical example of ...201021327112
the vibrio cholerae type vi secretion system: evaluating its role in the human disease cholera.vibrio cholerae, the marine bacterium responsible for the diarrheal disease cholera, utilizes a multitude of virulence factors to cause disease. the importance of two of these factors, the toxin co-regulated pilus (tcp) and cholera toxin (ct), has been well documented for pandemic o1 and epidemic o139 serogroups. in contrast, endemic non-o1 and non-o139 serogroups can cause localized outbreaks of cholera-like illness, often in the absence of tcp and ct. one virulence mechanism used by these stra ...201021607085
[effect of neutrophilokines on functional activity of macrophages during formation of immunity against cholera].to study effect of neutrophilokines on functional activity of macrophages (mph) during formation of immunity against cholera.201021381379
[comparative assessment of dot-immunoassay and immunochromatography methods for detection of 01 serogroup of vibrio cholerae].comparative study of sensitivity and specificity of immunochromatographic (ic) assay kit and dot-immunoanalysis for assessment of feasibility of their use for laboratory diagnostics of cholera.201021381382
1885 cholera controversy: klein versus koch.this paper will try to give new insight into the cholera controversy, which occurred 125 years ago. the majority of papers already written on the topic have emphasised the role of robert koch who described the comma bacillus as the cause of cholera epidemics. at the same time they have marginalised the role of emanuel edward klein by stating that he was wrong when he objected to robert koch's statement, because as an employee of the british government he was politically motivated. moreover, they ...201021393276
[cholera--once and nowadays].cholera is an acute intestinal infection which raged in india in the nineteenth century and it broke out in six great pandemics out in europe. etiology: cholera is caused by bacteria vibrio cholerae, which produce an enterotoxin causing massive diarrhoea. there are two biotypes--classic and el tor.201021446152
antibiotic susceptibility patterns of vibrio cholerae isolates.cholera is one of the most common diarrhoeal diseases in nepal. etiological agent of cholera is vibrio cholerae which removes essential body fluids, salts and vital nutrients, which are necessary for life causing dehydration and malnutrition. emerging antimicrobial resistant is common. the aim of the present study was to determine the antibiotic susceptibility pattern of cholera patients in nepal.201022049830
first-trimester prenatal diagnosis for huntington's disease with dna probes.polymorphic dna probes linked to the locus for huntington disease (hd) were used for prenatal diagnosis of a 10-week fetus at 25% risk for the disease. the fetus proved to have a 48% risk of having inherited the hd mutation which was similar to that for the at-risk parent (50%). on this basis the parents elected to terminate the pregnancy. when appropriate family members are available and dna studies are informative, prenatal diagnosis of hd with polymorphic dna probes can determine the at-risk ...20102884412
[causes of death and follow-up in life insurance. 5 years' study]. 20102873492
wilms tumors: relationship of nuclear deoxyribonucleic acid ploidy to patient survival.nuclear deoxyribonucleic acid ploidy studies with paraffin-embedded archival tumor specimens were performed by flow cytometry on extracted nuclei from 56 wilms tumors. before the era of chemotherapy 9 patients had a 33 per cent survival rate at 5 years. no significant correlation between deoxyribonucleic acid ploidy pattern and survival was seen in this early group of patients. since 1960, 47 patients underwent radical nephrectomy and received chemotherapy. deoxyribonucleic acid histograms in th ...20102821294
in vitro antibacterial activity of onion (allium cepa) against clinical isolates of vibrio cholerae.cholera is a major public health problem in developing countries of the world. bacterial resistance, lack of surveillance data and proper microbiological facilities are major problems regarding diagnosis of cholera. the spread of microbial drug resistance is a global public health challenge that results in increased illness and death rate. newer antimicrobials or agents are urgently required to overcome this problem. this work was therefore done to investigate the antimicrobial potential of onio ...201021702293
natural transformation of vibrio fischeri requires tfox and tfoy.recent evidence has indicated that natural genetic transformation occurs in vibrio cholerae, and that it requires both induction by chitin oligosaccharides, like chitohexaose, and expression of a putative regulatory gene designated tfox. using sequence and phylogenetic analyses we have found two tfox paralogues in all sequenced genomes of the genus vibrio. like v. cholerae, when grown in chitohexaose, cells of v. fischeri are able to take up and incorporate exogenous dna. chitohexaose-independen ...201021966921
different types of cell death induced by enterotoxins.the infection of bacterial organisms generally causes cell death to facilitate microbial invasion and immune escape, both of which are involved in the pathogenesis of infectious diseases. in addition to the intercellular infectious processes, pathogen-produced/secreted enterotoxins (mostly exotoxins) are the major weapons that kill host cells and cause diseases by inducing different types of cell death, particularly apoptosis and necrosis. blocking these enterotoxins with synthetic drugs and vac ...201022069678
evidence aid and the disaster response in pakistan and haiti.this editorial has also been recorded as a podcast; please click here to access.as if a natural disaster was not enough, vibrio cholerae emerged to make the situation worse in post-flood pakistan, and for the first time since the 1960s in post-earthquake haiti . how do we, as researchers, policy-makers and human beings, respond to such situations? in response to the tsunami on 26 december 2004, concerned reviewers within the cochrane collaboration established evidence aid - an initiative that po ...201021833937
vopf, a type iii effector protein from a non-o1, non-o139 vibrio cholerae strain, demonstrates toxicity in a saccharomyces cerevisiae model.vopf, a type iii effector protein, has been identified as a contributory factor to the intestinal colonization of type iii secretion system-positive, non-o1, non-o139 vibrio cholerae strains. to gain more insight into the function of vopf, a yeast model was developed. using this model, it was found that ectopic expression of vopf conferred toxicity in yeast.201019779031
laboratory-acquired vibrio cholerae o1 infection in austria, 2008.vibrio cholerae infection is a rare but well-documented cause of laboratory-associated illness. we report on the first case of indigenous cholera documented in austria after more than fifty years. in april 2008, the national reference centre for v. cholerae received an isolate of v. cholerae o1, serotype ogawa, cultured from the stool specimen of a patient consulting a general practitioner because of watery diarrhea. the 23 year old microbiology student had been working with viable v. cholerae f ...201019735275
transfer of cholera toxin genes from o1 to non-o1/o139 strains by vibriophages from california coastal waters.vibrio cholerae is an important bacterial pathogen that causes global cholera epidemic. although they are commonly found in coastal waters around the world, most environmental isolates do not contain cholera toxin genes. this study investigates vibriophages in southern california coastal waters and their ability to transfer cholera toxin genes.201019735324
multimeric bivalent immunogens from recombinant tetanus toxin hc fragment, synthetic hexasaccharides, and a glycopeptide adjuvant.using recombinant tetanus toxin h(c) fragment (rtt-h(c)) as carrier, we prepared multimeric bivalent immunogens featuring the synthetic hexasaccharide fragment of o-ps of vibrio cholerae o:1, serotype ogawa, in combination with either the synthetic hexasaccharide fragment of o-ps of vibrio cholerae o:1, serotype inaba, or a synthetic disaccharide tetrapeptide peptidoglycan fragment as adjuvant. the conjugation reaction was effected by squaric acid chemistry and monitored in virtually real time b ...201019757026
enteric bacterial pathogen detection in southern sea otters (enhydra lutris nereis) is associated with coastal urbanization and freshwater runoff.although protected for nearly a century, california's sea otters have been slow to recover, in part due to exposure to fecally-associated protozoal pathogens like toxoplasma gondii and sarcocystis neurona. however, potential impacts from exposure to fecal bacteria have not been systematically explored. using selective media, we examined feces from live and dead sea otters from california for specific enteric bacterial pathogens (campylobacter, salmonella, clostridium perfringens, c. difficile an ...201019720009
transcriptomics of enterotoxigenic escherichia coli infection. individual variation in intestinal gene expression correlates with intestinal function.acute secretory diarrhea is a major cause of morbidity and mortality in young animals and humans. deaths result from excessive fluid and electrolyte losses. the disease is caused by non-invasive bacteria such as vibrio cholerae and escherichia coli which produce enterotoxins, however, much less is known about the role of individual host responses. here we report the response of intact porcine small intestinal mucosa to infection with enterotoxigenic e. coli (etec). jejunal segments in four pigle ...201019716242
escherichia coli autoinducer-2 uptake network does not display hysteretic behavior but ai-2 synthesis rate controls transient bifurcation.analysis of different architectures of quorum sensing networks has been the center of attention in recent times. the approach employs mathematical models to uncover the factors behind the dynamics. quorum sensing networks mostly display autoregulation such as pseudomonas aeruginosa and vibrio cholerae. however, escherichia coli autoinducer-2 (ai-2) synthesis does not display autoinduction (i.e. autoregulation). this and other features have raised questions about the actual function of ai-2 insid ...201019695305
el tor cholera with severe disease: a new threat to asia and beyond.during epidemics of cholera in two rural sites (bakerganj and mathbaria), a much higher proportion of patients came for treatment with severe dehydration than was seen in previous years. v. cholerae o1 isolated from these patients was found to be el tor in its phenotype, but its cholera toxin (ct) was determined to be that of classical biotype. whether the observed higher proportion of severe dehydration produced by the el tor biotype was due to a shift from el tor to classical ct or due to othe ...201019678971
on spatially explicit models of cholera epidemics.we generalize a recently proposed model for cholera epidemics that accounts for local communities of susceptibles and infectives in a spatially explicit arrangement of nodes linked by networks having different topologies. the vehicle of infection (vibrio cholerae) is transported through the network links that are thought of as hydrological connections among susceptible communities. the mathematical tools used are borrowed from general schemes of reactive transport on river networks acting as the ...201019605400
three-dimensional structure of the detergent-solubilized vibrio cholerae cytolysin (vcc) heptamer by electron cryomicroscopy.vibrio cholerae cytolysin (vcc) is a pore-forming toxin that inserts a lytic water-filled channel into susceptible host membranes. assembly of the toxin on cell surfaces may be enhanced by two tandem lectin domains, in addition to direct interactions with lipids and cholesterol within the membrane itself. we used single-particle electron cryomicroscopy (cryoem) to generate a low-resolution molecular structure of the detergent-solubilized vcc oligomer to 20a resolution. after confirming a heptame ...201019616104
differential expression of enteric neuroimmune-network in invasive and acute watery diarrhoea.we aimed to evaluate the changes of nerve morphology and distribution of neurotransmitters and neuropeptides in the rectum of shigella flexneri-infected patients and in the duodenum of vibrio cholerae o1-infected patients. nerve morphology was observed by transmission electron microscopy. immunoreactivity of nerve growth factor (ngf), neurotransmitters and neuropeptides in tissues were studied by immunohistochemistry. ultrastructural analysis of intestinal biopsy revealed persisting axons degene ...201019650770
single dose azithromycin versus ciprofloxacin for cholera in children: a randomized controlled trial.to compare the clinical and bacteriological success of single dose treatment with azithromycin and ciprofloxacin in children with cholera.201019578229
genetic determinants of virulence, antibiogram and altered biotype among the vibrio cholerae o1 isolates from different cholera outbreaks in india.cholera diarrhea is still a major health challenge for a large part of globe. global replacement of vibrio cholerae classical biotype by el tor biotype, emergence of o139 serogroup and rapid spread of antibiotic resistant strains indicate the continuous evolution in v. cholerae. in this study, 114 v. cholerae o1 serotype ogawa isolates, collected from different cholera outbreaks in different regions of india between 2004 and 2007 were subjected to biochemical, immunological and molecular charact ...201019580888
characterization of potentially virulent non-o1/non-o139 vibrio cholerae strains isolated from human patients.traditional methods of typing vibrio cholerae define virulent strains according to their recognition by sera directed against the known epidemic serogroups o1 and o139, overlooking potentially virulent non-o1/non-o139 strains. here, we have undertaken the characterization of eight clinical isolates of non-o1/non-o139 v. cholerae, collected during cholera outbreaks in brazil. seven of these were typed as o26 and one, 17155, was defined as non-typable. a pcr-based approach has previously detected ...201019456828
production of monoclonal antibodies specific to major outer membrane protein of edwardsiella tarda.edwardsiella tarda is an important cause for hemorrhagic septicemia in fish and gastro and extra-intestinal infections in humans. monoclonal antibodies (mabs) were produced against outer membrane proteins (omps) of e. tarda et-7, isolated from diseased snakehead (ophiocephalus punctatus). two stable hybridoma clones, designated as 3f10 and 2c3 mabs were found to be potentially specific for e. tarda by indirect enzyme linked immunosorbent assay (elisa). these mabs recognized major immunogenic omp ...201018804863
diagnostic limitations to accurate diagnosis of cholera.the treatment regimen for diarrhea depends greatly on correct diagnosis of its etiology. recent diarrhea outbreaks in bangladesh showed vibrio cholerae to be the predominant cause, although more than 40% of the suspected cases failed to show cholera etiology by conventional culture methods (cms). in the present study, suspected cholera stools collected from every 50th patient during an acute diarrheal outbreak were analyzed extensively using different microbiological and molecular tools to deter ...201020739485
a fatal vibrio cholerae o37 enteritis. 201020798215
[study of expression of contact-dependent secretion systems in vibrio cholerae on the model of dictyostelium discoideum].to detect t3ss and t6ss genes in vibrio cholerae genomes and assessment of resistance of strains with different genotype characteristics to ingestion by dictyostelium discoideum amoeba.201020799403
cholera outbreak in baghdad in 2007: an epidemiological study.in 2007 there was an epidemic of cholera in iraq with 4667 cases. the first case in baghdad was diagnosed on 19 september 2007 and the last case on 13 december 2007. in all, 136 cases were reported (2.9% of the country total) in 6 of the 13 districts of baghdad. the median age of the cases was 11 years (range = 0.3-71 years). there were 3 deaths giving a case fatality rate of 2.2%. bacteriological testing confirmed that the outbreak was caused by vibrio cholerae o1, biotype el tor, serotype inab ...201020799583
extracts of edible and medicinal plants damage membranes of vibrio cholerae.the use of natural compounds from plants can provide an alternative approach against food-borne pathogens. the mechanisms of action of most plant extracts with antimicrobial activity have been poorly studied. in this work, changes in membrane integrity, membrane potential, internal ph (ph(in)), and atp synthesis were measured in vibrio cholerae cells after exposure to extracts of edible and medicinal plants. a preliminary screen of methanolic, ethanolic, and aqueous extracts of medicinal and edi ...201020802077
reduced expression of the vca0421 gene of vibrio cholerae o1 results in innate resistance to ciprofloxacin.a mini-tn5 insertion into a ciprofloxacin (cip)-resistant mutant of vibrio cholerae o1 revealed that overexpression of the vca0421 gene, which encodes a hypothetical protein, in the cip-resistant mutant carrying a mutation in the quinolone resistance-determining region (qrdr) of the gyra gene causes sensitization to cip. we propose a new intrinsic mechanism of resistance to fluoroquinolones due to the inherently reduced expression of the vca0421 gene in v. cholerae o1.201020805389
cholera toxin production by the el tor variant of vibrio cholerae o1 compared to prototype el tor and classical biotypes.vibrio cholerae o1 el tor variant strains produced much more cholera toxin than did prototype el tor strains. the amount of cholera toxin produced by el tor variant strains both in vitro and in vivo was more or less equivalent to that produced by classical strains.201020810767
structure elucidation of two new bisbenzylisoquinoline alkaloids and nmr assignments of the alkaloids from the fruits of tiliacora racemosa.besides three known biphenyldibenzodioxinbisbenzylisoquinoline alkaloids, two novel alkaloids of the same group have been isolated from the fruits of tiliacora racemosa. the structures of these new compounds designated tiliaimine and nordinklacorine were established on the basis of 1d and 2d nmr spectroscopy, including cosy, tocsy, roesy, hmbc and hsqc experiments. preliminary antibacterial activity studies on the known compounds (tiliarine, 2'-nortiliacorinine, 2'-nortiliacorine) from the fruit ...201020812212
cholera toxin inhibits hiv-1 replication in human colorectal epithelial ht-29 cells through adenylate cyclase activation.mixed feeding, combining breast milk and nonhuman milk and/or solid food, is a common practice in developing countries that increases the risk of vertical hiv-1 transmission. it also enhances the risk of infection by waterborne microorganisms such as vibrio cholerae, a diarrhoea-causing pathogen that frequently infects children below 18 months of age. although both hiv-1 and v. cholerae affect young children and target intestinal epithelial cells, no information is currently available on possibl ...201020816895
freshwater non-o1 vibrio cholerae infection.it is not appreciated by most physicians that vibrio infections can be acquired from freshwater exposure. a case of non-o1 vibrio cholerae urinary tract infection associated with freshwater exposure is reported. the potential for vibrios to grow in brachish water and for summer heat to cause evaporation leading to relative increased salinity in freshwater bodies and the broad geographic range of these occurrences to include north american and both eastern and western europe is noted. a literatur ...201020818301
novel insights into haemagglutinin protease (hap) gene regulation in vibrio cholerae.abstract quorum sensing is the phenomenon, whereby bacteria use signal molecules to communicate with each other. for example, to establish a successful infection, pathogenic bacteria become virulent only when they reach a certain local concentration in their host. bassler and others have highlighted the surprising observation that quorum sensing seems to repress vibrio cholerae virulence factor expression (e.g. cholera toxin), in contrast to what has been observed for virulence gene expression i ...201020819164
analysis of a cholera toxin b subunit (ctb) and human mucin 1 (muc1) conjugate protein in a muc1-tolerant mouse model.since epithelial mucin 1 (muc1) is associated with several adenocarcinomas at the mucosal sites, it is pertinent to test the efficacy of a mucosally targeted vaccine formulation. the b subunit of the vibrio cholerae cholera toxin (ctb) has great potential to act as a mucosal carrier for subunit vaccines. in the present study we evaluated whether a muc1 tandem repeat (tr) peptide chemically linked to ctb would break self-antigen tolerance in the transgenic muc1-tolerant mouse model (muc1.tg) thro ...201020824430
is vibrio fluvialis emerging as a pathogen with epidemic potential in coastal region of eastern india following cyclone aila?an isolated area with diarrhoea epidemic was explored at pakhirala village of the sundarbans, a coastal region of south 24 parganas district of west bengal, eastern india. the pakhirala village was surrounded by other villages affected by a similar epidemic. the affected villages experienced this epidemic following the cyclone aila, which had hit the coastal region of the sundarbans in eastern india. in pakhirala, the situation was the worst. within a span of six weeks (5 june-20 july 2009), 3,5 ...201020824973
the effect of zinc oxide nanoparticles on the structure of the periplasmic domain of the vibrio cholerae toxr protein.proteins adsorbed on nanoparticles (nps) are being used as biosensors and in drug delivery. however, our understanding of the effect of nps on the structure of proteins is still in a nascent state. in this work we report the unfolding behavior of the periplasmic domain of the toxr protein (toxrp) of vibrio cholerae on zinc oxide (zno) nanoparticles with a diameter of 2.5 nm. this protein plays a crucial role in regulating the expression of several virulence factors in the pathogenesis of cholera ...201020825484
molecular evidence of cholera outbreak caused by a toxigenic vibrio cholerae o1 el tor variant strain in kelantan, malaysia.a total of 20 vibrio cholerae isolates were recovered for investigation from a cholera outbreak in kelantan, malaysia, that occurred between november and december 2009. all isolates were biochemically characterized as v. cholerae serogroup o1 ogawa of the el tor biotype. they were found to be resistant to multiple antibiotics, including tetracycline, erythromycin, sulfamethoxazole-trimethoprim, streptomycin, penicillin g, and polymyxin b, with 35% of the isolates being resistant to ampicillin. a ...201020826646
conversion of viable but nonculturable vibrio cholerae to the culturable state by co-culture with eukaryotic cells.vbnc vibrio cholerae o139 vc-280 obtained by incubation in 1% solution of artificial sea water io at 4°c for 74 days converted to the culturable state when co-cultured with cho cells. other eukaryotic cell lines, including ht-29, caco-2, t84, hela, and intestine 407, also supported conversion of vbnc cells to the culturable state. conversion of vbnc v. cholerae o1 n16961 and v. cholerae o139 vc-280/pg13 to the culturable state, under the same conditions, was also confirmed. when vbnc v. cholerae ...201020840148
syntaxin 3 is necessary for camp- and cgmp-regulated exocytosis of cftr: implications for enterotoxigenic diarrhea.enterotoxins elaborated by vibrio cholerae and escherichia coli cannot elicit fluid secretion in the absence of functional cystic fibrosis transmembrane conductance regulator (cftr) chloride channels. after enterotoxin exposure, cftr channels are rapidly recruited from endosomes and undergo exocytic insertion into the apical plasma membrane of enterocytes to increase the number of channels on the cell surface by at least fourfold. however, the molecular machinery that orchestrates exocytic inser ...201020844248
genomic evolution of vibrio cholerae.vibrio cholera, the causal agent of cholera, also occupies an autochthonous aquatic inhabitant. the current, seventh cholera pandemic is linked to o1 el tor biotype and o139 serogroups. in the last decades, we have witnessed a shift involving genetically and phenotypically varied pandemic clones in asia and africa. recent comparative genomic studies have identified a large 'mobilome', or composed of mobile genomic islands in v. cholerae. all seventh pandemic isolates have highly related genome s ...201020851041
back to the future: studying cholera pathogenesis using infant rabbits.cholera is a severe diarrheal disease, caused by vibrio cholerae, for which there has been no reproducible, nonsurgical animal model. here, we report that orogastric inoculation of v. cholerae into 3-day-old rabbits pretreated with cimetidine led to lethal, watery diarrhea in virtually all rabbits. the appearance and chemical composition of the rabbit diarrheal fluid were comparable to those of the "rice-water stool" produced by cholera patients. as in humans, v. cholerae mutants that do not pro ...201020689747
evaluating the growth potential of pathogenic bacteria in water.the degree to which a water sample can potentially support the growth of human pathogens was evaluated. for this purpose, a pathogen growth potential (pgp) bioassay was developed based on the principles of conventional assimilable organic carbon (aoc) determination, but using pure cultures of selected pathogenic bacteria (escherichia coli o157, vibrio cholerae, or pseudomonas aeruginosa) as the inoculum. we evaluated 19 water samples collected after different treatment steps from two drinking wa ...201020693455
cloning, overexpression, purification, crystallization and preliminary x-ray analysis of chey3, a response regulator that directly interacts with the flagellar 'switch complex' in vibrio cholerae.vibrio cholerae is the aetiological agent of the severe diarrhoeal disease cholera. this highly motile organism uses the processes of motility and chemotaxis to travel and colonize the intestinal epithelium. chemotaxis in v. cholerae is far more complex than that in escherichia coli or salmonella typhimurium, with multiple paralogues of various chemotaxis genes. in contrast to the single copy of the chemotaxis response-regulator protein chey in e. coli, v. cholerae contains four cheys (chey1-che ...201020693676
epidemiological characteristics of cholera in singapore, 1992-2007.we carried out an epidemiological review of cholera in singapore to determine its trends and the factors contributing to its occurrence.201020697667
genetic manipulation of vibrio cholerae by combining natural transformation with flp recombination.even though vibrio cholerae is a well-known human pathogen, it is also a normal member of aquatic habitats. within this environment it often forms biofilms on the chitin-containing exoskeleton of crustaceans and their molts. chitin not only serves as nutrient source but also induces a developmental program called natural competence. naturally competent bacteria take up free dna and integrate it into their genome by homologous recombination, thereby becoming naturally transformed. in this study, ...201020709100
high prevalence of multidrug-resistant strains of vibrio cholerae, in a cholera outbreak in tehran-iran, during june-september 2008.following the occurrence of suspected cases of vibrio cholerae in karaj in 2008, this study was conducted in order to determine whether or not the cases were infected with cholera and, if so, to describe the prevalence of serotypes, route of transmission and the antimicrobial resistance profile. in this cross-sectional study, 6505 rectal swabs were collected from patients with acute gastroenteritis. serotypes and biotypes of the isolates were determined by standard procedures. the antimicrobial ...201020709810
lt-iic, a new member of the type ii heat-labile enterotoxin family encoded by an escherichia coli strain obtained from a nonmammalian host.two families of bacterial heat-labile enterotoxins (hlts) have been described: the type i hlts are comprised of cholera toxin (ct) of vibrio cholerae, lt-i of escherichia coli, and several related hlts; the type ii hlts are comprised of lt-iia and lt-iib. herein, we report lt-iic, a new type ii hlt encoded from an enterotoxigenic e. coli (etec) strain isolated from an avian host. using a mouse y1 adrenal cell bioassay, lt-iic was shown to be less cytotoxic than ct, lt-iia, or lt-iib. cytotoxicit ...201020713622
dissection of the conformational cycle of the multidrug/lipida abc exporter msba.recent crystal structures of the multidrug atp-binding cassette (abc) exporters sav1866 from staphylococcus aureus, msba from escherichia coli, vibrio cholera, and salmonella typhimurium, and mouse abcb1a suggest a common alternating access mechanism for export. however, the molecular framework underlying this mechanism is critically dependent on assumed conformational relationships between nonidentical crystal structures and therefore requires biochemical verification. the structures of homodim ...201020715055
the diheme cytochrome c(4) from vibrio cholerae is a natural electron donor to the respiratory cbb(3) oxygen reductase.the respiratory chain of vibrio cholerae contains three bd-type quinol oxygen reductases as well as one cbb(3) oxygen reductase. the cbb(3) oxygen reductase has been previously isolated and characterized; however, the natural mobile electron donor(s) that shuttles electrons between the bc(1) complex and the cbb(3) oxygen reductase is not known. the most likely candidates are the diheme cytochrome c(4) and monoheme cytochrome c(5), which have been previously shown to be present in the periplasm o ...201020715760
immunological efficacy of glycoconjugates derived from vibrio cholerae o1 serotype ogawa detoxified lps in mice.this study focused on changes in selected parameters of humoral and cellular immunity following vaccination of mice with unique vibrio cholerae lps-protein-complexed conjugates. the v. cholerae detoxified lps (dlps)-derived antigenic structures o-specific polysaccharide (o-sp) and de-o-acylated lps (deoac-lps) were used to prepare glycoconjugates by linking both dlpss to glucan, the immunomodulating matrix, and then to bsa carrier. animals were given a primary vaccination and boosted at 2-week i ...201020724514
[2007 cholera epidemic in comoros islands: a step towards endemisation?].in 2007, a cholera epidemic occurred on two of the three islands of the comoros archipelago: grande comore and moheli. this study is based on data from the files of the 1571 patients admitted to five cholera treatment centers (ctc). the outbreak lasted for ten months. a dramatic peak was observed in july and august corresponding to the traditional wedding season during which hundreds of guests including returning diaspora gather to celebrate "grand marriages". initial stool cultures identified v ...201020734608
structure of the cholera toxin secretion channel in its closed state.the type ii secretion system (t2ss) is a macromolecular complex spanning the inner and outer membranes of gram-negative bacteria. remarkably, the t2ss secretes folded proteins, including multimeric assemblies such as cholera toxin and heat-labile enterotoxin from vibrio cholerae and enterotoxigenic escherichia coli, respectively. the major outer membrane t2ss protein is the 'secretin' gspd. cryo-em reconstruction of the v. cholerae secretin at 19-å resolution reveals a dodecameric structure remi ...201020852644
identification of selective enzyme inhibitors by fragment library screening.the microbial threat to human health is growing due to the dramatic increase in the number of multidrug-resistant organisms. the decline in effective antibiotics available to treat these growing threats has provided greater urgency to the search for new antibiotics. clearly, new approaches must be developed against novel targets to control these resistant infectious organisms. the screening of low molecular weight compounds against new protein targets provides an opportunity to identify novel in ...201020855558
glycation sites in neoglycoglycoconjugates from the terminal monosaccharide antigen of the o-ps of vibrio cholerae o1, serotype ogawa, and bsa revealed by matrix-assisted laser desorption-ionization tandem mass spectrometry.we present the maldi-tof/tof-ms analyses of various hapten-bovine serum albumin (bsa) neoglycoconjugates obtained by squaric acid chemistry coupling of the spacer-equipped, terminal monosaccharide of the o-specific polysaccharide of vibrio cholerae o1, serotype ogawa, to bsa. these analyses allowed not only to calculate the molecular masses of the hapten-bsa neoglycoconjugates with different hapten-bsa ratios (4.3, 6.6 and 13.2) but, more importantly, also to localize the covalent linkages (conj ...201020860010
structure of a cation-bound multidrug and toxic compound extrusion transporter.transporter proteins from the mate (multidrug and toxic compound extrusion) family are vital in metabolite transport in plants, directly affecting crop yields worldwide. mate transporters also mediate multiple-drug resistance (mdr) in bacteria and mammals, modulating the efficacy of many pharmaceutical drugs used in the treatment of a variety of diseases. mate transporters couple substrate transport to electrochemical gradients and are the only remaining class of mdr transporters whose structure ...201020861838
a bistable switch and anatomical site control vibrio cholerae virulence gene expression in the intestine.a fundamental, but unanswered question in host-pathogen interactions is the timing, localization and population distribution of virulence gene expression during infection. here, microarray and in situ single cell expression methods were used to study vibrio cholerae growth and virulence gene expression during infection of the rabbit ligated ileal loop model of cholera. genes encoding the toxin-coregulated pilus (tcp) and cholera toxin (ct) were powerfully expressed early in the infectious proces ...201020862321
treatment of cholera-like diarrhoea with oral rehydration.cholera diarrhoea remains a major global health problem that has caused seven pandemics. the pathogenesis of cholera is attributable to the production of cholera toxin by the causative pathogen, vibrio cholerae. the toxin causes increased production of cyclic adenosine monophosphate and this results in massive water and electrolyte secretion into the intestinal lumen. these changes manifest clinically as the painless defecation of voluminous stools that resemble 'rice water', leading to severe d ...201020863435
stochastic dynamics of cholera epidemics.we describe the predictions of an analytically tractable stochastic model for cholera epidemics following a single initial outbreak. the exact model relies on a set of assumptions that may restrict the generality of the approach and yet provides a realm of powerful tools and results. without resorting to the depletion of susceptible individuals, as usually assumed in deterministic susceptible-infected-recovered models, we show that a simple stochastic equation for the number of ill individuals p ...201020866255
inhibition of vibrio cholerae biofilm by aiia enzyme produced from bacillus spp.vibrio cholerae is the causative agent of water-borne diarrheal disease, cholera. the formation of biofilm favors survival and persistence of v. cholerae in the aquatic environment and also inside the host. ahl lactonase (aiia), a metallo-beta-lactamase produced by bacillus spp., blocks quorum sensing in gram-negative bacteria by hydrolyzing n-acyl-homoserine lactones (ahls). in the present investigation, aiia-mediated inhibition of v. cholerae biofilm was studied. two novel alleles of aiia-enco ...201020872263
a case of nosocomial cholera during a community outbreak in a thai-myanmar border area.the present study presents a case of nosocomial cholera in one general hospital located in a thai-myanmar border area. between may and october 2007, a community outbreak of cholera with 477 cases took place in mae sot district, tak province. a 71-year-old diabetic female who had undergone craniotomy following intracerebral hemorrhage contracted nosocomial cholera with mild diarrhea on august 6, 2007, 37 days after admission in a female ward of the mae sot hospital. she received a nasogastric tub ...201020873088
high-resolution structure of the nitrile reductase quef combined with molecular simulations provide insight into enzyme mechanism.here, we report the 1.53-å crystal structure of the enzyme 7-cyano-7-deazaguanine reductase (quef) from vibrio cholerae, which is responsible for the complete reduction of a nitrile (cn) bond to a primary amine (h(2)c-nh(2)). at present, this is the only example of a biological pathway that includes reduction of a nitrile bond, establishing quef as particularly noteworthy. the structure of the quef monomer resembles two connected ferrodoxin-like domains that assemble into dimers. ligands identif ...201020875425
antimicrobial suceptibility of v. cholerae in north west, ethiopia.various vibrio cholerae serogroups cause cholera, which occurs as major epidemic disease in most developing countries. this study was aimed at determining the antimicrobial susceptibility patterns of v. cholerae and its serotypes from cholera cases.201020607994
energy transducing redox steps of the na+-pumping nadh:quinone oxidoreductase from vibrio cholerae.na(+)-nqr is a unique respiratory enzyme that couples the free energy of electron transfer reactions to electrogenic pumping of sodium across the cell membrane. this enzyme is found in many marine and pathogenic bacteria where it plays an analogous role to the h(+)-pumping complex i. it has generally been assumed that the sodium pump of na(+)-nqr operates on the basis of thermodynamic coupling between reduction of a single redox cofactor and the binding of sodium at a nearby site. in this study, ...201020616050
non-o1, non-o139 vibrio cholerae bacteraemia in a cirrhotic patient.vibrio cholerae serogroups o1 or o139 are the aetiological agents of cholera. the pathogenicity of non-o1, non-o139 v. cholerae is less well known. these worldwide bacteria are responsible for gastrointestinal infections or, more rarely, bacteraemia in patients with an underlying disease, leading to life-threatening complications. we report a case of non-o1, non-o139 v. cholerae bacteraemia due to a haemolytic strain in a cirrhotic patient. early antibiotherapy allowed a good outcome. the aim of ...201020616193
effect of storage and sodium chloride on excision of ctxphi or pre-ctxphi and ctxphi from vibrio cholerae o139 strains.we examined the effect of storage and sodium chloride on excision of ctxphi or pre-ctxphi and ctxphi from vibrio cholerae o139 strains. we found that one strain of v. cholerae o139 vo146p showed loss of the complete phage array, and other strain vo170p showed partial loss of the phage array giving rise to altered strains designated as vo146n and vo170n. results of pcr and rflp analysis revealed that both strains (vo146p and vo170p) possessed a single copy of pre-ctx(et)phi and two copies of ctxp ...201020621579
identification and characterization of a phosphodiesterase that inversely regulates motility and biofilm formation in vibrio cholerae.vibrio cholerae switches between free-living motile and surface-attached sessile lifestyles. cyclic diguanylate (c-di-gmp) is a signaling molecule controlling such lifestyle changes. c-di-gmp is synthesized by diguanylate cyclases (dgcs) that contain a ggdef domain and is degraded by phosphodiesterases (pdes) that contain an eal or hd-gyp domain. we constructed in-frame deletions of all v. cholerae genes encoding proteins with ggdef and/or eal domains and screened mutants for altered motility ph ...201020622061
inositol hexakisphosphate-induced autoprocessing of large bacterial protein toxins.large bacterial protein toxins autotranslocate functional effector domains to the eukaryotic cell cytosol, resulting in alterations to cellular functions that ultimately benefit the infecting pathogen. among these toxins, the clostridial glucosylating toxins (cgts) produced by gram-positive bacteria and the multifunctional-autoprocessing rtx (martx) toxins of gram-negative bacteria have distinct mechanisms for effector translocation, but a shared mechanism of post-translocation autoprocessing th ...201020628577
chicken cathelicidin-2-derived peptides with enhanced immunomodulatory and antibacterial activities against biological warfare agents.host defence peptides (hdps) are considered to be excellent candidates for the development of novel therapeutic agents. recently, it was demonstrated that the peptide c1-15, an n-terminal segment of chicken hdp cathelicidin-2, exhibits potent antibacterial activity while lacking cytotoxicity towards eukaryotic cells. in the present study, we report that c1-15 is active against bacteria such as bacillus anthracis and yersinia pestis that may potentially be used by bioterrorists. substitution of s ...201020630709
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