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predicting the distribution of vibrio spp. in the chesapeake bay: a vibrio cholerae case study.vibrio cholerae, the causative agent of cholera, is a naturally occurring inhabitant of the chesapeake bay and serves as a predictor for other clinically important vibrios, including vibrio parahaemolyticus and vibrio vulnificus. a system was constructed to predict the likelihood of the presence of v. cholerae in surface waters of the chesapeake bay, with the goal to provide forecasts of the occurrence of this and related pathogenic vibrio spp. prediction was achieved by driving an available mul ...201020145974
the secretome of campylobacter concisus.a higher prevalence of campylobacter concisus and higher levels of igg antibodies specific to c. concisus in crohn's disease patients than in controls were recently detected. in this study, 1d and 2d gel electrophoresis coupled with ltq ft-ms and qstar tandem ms, respectively, were performed to characterize the secretome of a c. concisus strain isolated from a crohn's disease patient. two hundred and one secreted proteins were identified, of which 86 were bioinformatically predicted to be secret ...201020148967
vibrio cholerae vpst regulates matrix production and motility by directly sensing cyclic di-gmp.microorganisms can switch from a planktonic, free-swimming life-style to a sessile, colonial state, called a biofilm, which confers resistance to environmental stress. conversion between the motile and biofilm life-styles has been attributed to increased levels of the prokaryotic second messenger cyclic di-guanosine monophosphate (c-di-gmp), yet the signaling mechanisms mediating such a global switch are poorly understood. here we show that the transcriptional regulator vpst from vibrio cholerae ...201020150502
in vivo actin cross-linking induced by vibrio cholerae type vi secretion system is associated with intestinal inflammation.type vi secretion systems (t6sss) have recently been recognized as potential virulence determinants of many gram-negative bacterial pathogens. although mechanistic studies are lacking, t6ss-dependent phenotypes can be observed in various animal models of infection. presumably translocation of t6ss effectors into target cells is involved in virulence, but few such effectors have been identified. a hallmark of t6ss function is the in vitro secretion of hcp and vgrg proteins, which are thought to f ...201020150509
role of flgt in anchoring the flagellum of vibrio cholerae.flagellar motility has long been regarded as an important virulence factor. in vibrio cholerae, the single polar flagellum is essential for motility as well as for proper attachment and colonization. in this study, we demonstrate that the novel flagellar protein flgt is involved in anchoring the flagellum to the v. cholerae cell. a screen for novel colonization factors by use of tnphoa mutagenesis identified flgt. an in-frame deletion of flgt established that flgt is required for attachment, col ...201020154133
polymyxin b resistance in el tor vibrio cholerae requires lipid acylation catalyzed by msbb.antimicrobial peptides are critical for innate antibacterial defense. both gram-negative and gram-positive microbes have mechanisms to alter their surfaces and resist killing by antimicrobial peptides. in vibrio cholerae, two natural epidemic biotypes, classical and el tor, exhibit distinct phenotypes with respect to sensitivity to the peptide antibiotic polymyxin b: classical strains are sensitive and el tor strains are relatively resistant. we carried out mutant screens of both biotypes, aimin ...201020154134
reactogenicity of live-attenuated vibrio cholerae vaccines is dependent on flagellins.cholera is a severe diarrheal disease caused by the motile gram-negative rod vibrio cholerae. live-attenuated v. cholerae vaccines harboring deletions of the genes encoding cholera toxin have great promise for reducing the global burden of cholera. however, development of live vaccines has been hampered by the tendency of such strains to induce noncholeric reactogenic diarrhea in human subjects. the molecular bases of reactogenicity are unknown, but it has been speculated that reactogenic diarrh ...201020160087
the putative na+/h+ antiporter of vibrio cholerae, vc-nhap2, mediates the specific k+/h+ exchange in vivo.the existence of bacterial k(+)/h(+) antiporters that prevent the overaccumulation of potassium in the cytoplasm was predicted by peter mitchell almost 50 years ago. the importance of k(+)/h(+) antiport for bacterial physiology is widely recognized, but its molecular mechanisms remain underinvestigated. here, we demonstrate that a putative na(+)/h(+) antiporter, vc-nhap2, protects cells of vibrio cholerae growing at ph 6.0 from high concentrations of external k(+). resistance of v. cholerae to n ...201020163190
carbohydrate binding specificities and crystal structure of the cholera toxin-like b-subunit from citrobacter freundii.enterotoxigenic escherichia coli and vibrio cholerae are well known causative agents of severe diarrheal diseases. both pathogens produce ab(5) toxins, with one enzymatically active a-subunit and a pentamer of receptor-binding b-subunits. the primary receptor for both b-subunits is the gm1 ganglioside (galbeta3galnacbeta4(neuacalpha3)galbeta4glcbetacer), but the b-subunits from porcine isolates of e. coli also bind neolacto-(galbeta4glcnacbeta-)terminated glycoconjugates and the b-subunits from ...201020171259
concomitant enterotoxigenic escherichia coli infection induces increased immune responses to vibrio cholerae o1 antigens in patients with cholera in bangladesh.vibrio cholerae o1 and enterotoxigenic escherichia coli (etec) are major bacterial pathogens that cause dehydrating disease requiring hospitalization of children and adults. the cholera toxin (ct) produced by v. cholerae o1 and the heat-labile toxin (lt) and/or heat-stable toxin (st) of etec are responsible for secretory diarrhea. we have observed that about 13% of hospitalized diarrheal patients are concomitantly infected with v. cholerae o1 and etec. in order to understand the outcome of such ...201020176796
para2, a vibrio cholerae chromosome partitioning protein, forms left-handed helical filaments on dna.most bacterial chromosomes contain homologs of plasmid partitioning (par) loci. these loci encode atpases called para that are thought to contribute to the mechanical force required for chromosome and plasmid segregation. in vibrio cholerae, the chromosome ii (chrii) par locus is essential for chrii segregation. here, we found that purified para2 had atpase activities comparable to other para homologs, but, unlike many other para homologs, did not form high molecular weight complexes in the pres ...201020176965
multiple small rnas identified in mycobacterium bovis bcg are also expressed in mycobacterium tuberculosis and mycobacterium smegmatis.tuberculosis (tb) is a major global health problem, infecting millions of people each year. the causative agent of tb, mycobacterium tuberculosis, is one of the world's most ancient and successful pathogens. however, until recently, no work on small regulatory rnas had been performed in this organism. regulatory rnas are found in all three domains of life, and have already been shown to regulate virulence in well-known pathogens, such as staphylococcus aureus and vibrio cholera. here we report t ...201020181675
bacterial chromosome organization and segregation.bacterial chromosomes are generally approximately 1000 times longer than the cells in which they reside, and concurrent replication, segregation, and transcription/translation of this crowded mass of dna poses a challenging organizational problem. recent advances in cell-imaging technology with subdiffraction resolution have revealed that the bacterial nucleoid is reliably oriented and highly organized within the cell. such organization is transmitted from one generation to the next by progressi ...201020182613
chloroplast-derived vaccine antigens confer dual immunity against cholera and malaria by oral or injectable delivery.cholera and malaria are major diseases causing high mortality. the only licensed cholera vaccine is expensive; immunity is lost in children within 3 years and adults are not fully protected. no vaccine is yet available for malaria. therefore, in this study, the cholera toxin-b subunit (ctb) of vibrio cholerae fused to malarial vaccine antigens apical membrane antigen-1 (ama1) and merozoite surface protein-1 (msp1) was expressed in lettuce and tobacco chloroplasts. southern blot analysis confirme ...201020051036
virulence regulator aphb enhances toxr transcription in vibrio cholerae.vibrio cholerae is the causative agent of cholera. extensive studies reveal that complicated regulatory cascades regulate expression of virulence genes, the products of which are required for v. cholerae to colonize and cause disease. in this study, we investigated the expression of the key virulence regulator toxr under different conditions.201020053280
acute cholecystitis caused by nontoxigenic vibrio cholerae o1 inaba.a rare case of acute cholecystitis caused by serogroup o1 vibrio cholerae in an 83-year-old man is presented. his risk factors for cholecystitis included advanced age and previous abdominal surgeries. the patient had consumed raw oysters several days before presentation. the patient had a poor outcome after admission for this infection, likely due to his underlying illnesses that complicated his hospital course.201020053858
deletion of penicillin-binding protein 5 (pbp5) sensitises escherichia coli cells to beta-lactam agents.escherichia coli penicillin-binding protein 5 (pbp5), a dd-carboxypeptidase encoded by the daca gene, plays a key role in the maintenance of cell shape. although pbp5 shares one of the highest copy numbers among the pbps, it is not essential for cell survival. to determine the effect of this redundant pbp on beta-lactam antibiotic susceptibility, pbp5 was deleted from o-antigen-negative e. coli k-12 (cs109) and o8-antigen-positive e. coli 2443, thus creating strains am15-1 and ag1o5-1, respectiv ...201020047819
the el tor biotype of vibrio cholerae exhibits a growth advantage in the stationary phase in mixed cultures with the classical biotype.vibrio cholerae strains of the o1 serogroup that typically cause epidemic cholera can be classified into two biotypes, classical and el tor. the el tor biotype emerged in 1961 and subsequently displaced the classical biotype as a cause of cholera throughout the world. in this study we demonstrate that when strains of the el tor and classical biotypes were cocultured in standard lb medium, the el tor strains clearly had a competitive growth advantage over the classical biotype starting from the l ...201020023022
mechanisms involved in governing adherence of vibrio cholerae to granular starch.vibrio cholerae has been shown to adhere to cornstarch granules. the present work explored the mechanisms involved in this adhesion and the possibility of its occurrence in vivo. the findings suggest that both specific and nonspecific interactions are involved in the adhesion. nonspecific hydrophobic interactions may play a role, since both v. cholerae and cornstarch granules exhibited hydrophobic properties when they were tested using a xylene-water system. in addition, the presence of bile aci ...201020023099
critical evaluation of the volumetric "bottle effect" on microbial batch growth.we have analyzed the impact of surface-to-volume ratio on final bacterial concentrations after batch growth. we examined six bottle sizes (20 to 1,000 ml) using three independent enumeration methods to quantify growth. we found no evidence of a so-called volumetric bottle effect, thus contradicting numerous previous reports.201020023110
transferable quinolone resistance in vibrio cholerae.ciprofloxacin was introduced for treatment of patients with cholera in bangladesh because of resistance to other agents, but its utility has been compromised by the decreasing ciprofloxacin susceptibility of vibrio cholerae over time. we correlated levels of susceptibility and temporal patterns with the occurrence of mutation in gyra, which encodes a subunit of dna gyrase, followed by mutation in parc, which encodes a subunit of dna topoisomerase iv. we found that ciprofloxacin activity was more ...201019949057
evolution of new variants of vibrio cholerae o1.vibrio cholerae typically contains a prophage that carries the genes encoding the cholera toxin, which is responsible for the major clinical symptoms of the disease. in recent years, new pathogenic variants of v. cholerae have emerged and spread throughout many asian and african countries. these variants display a mixture of phenotypic and genotypic traits from the two main biotypes (known as 'classical' and 'el tor'), suggesting that they are genetic hybrids. classical and el tor biotypes have ...201019942436
multilocus variable-number tandem repeat analysis of vibrio cholerae o1 el tor strains harbouring classical toxin b.atypical vibrio cholerae o1 strains - hybrid strains (strains that cannot be classified either as el tor or classical biotype) and altered strains (el tor biotype strains that produce classical cholera toxin) - are currently prevalent in asia and africa. a total of 74 hybrid and altered strains that harboured classical cholera toxin were investigated by multilocus variable-number tandem repeat analysis (mlva). the results showed that the hybrid/altered strains could be categorized into three gro ...201020299504
chitin disaccharide (glcnac)2 induces natural competence in vibrio cholerae through transcriptional and translational activation of a positive regulatory gene tfoxvc.a pathogenic marine bacterium vibrio cholerae shows natural competence for genetic transformation in the presence of chitin, a polymer of n-acetylglucosamine (glcnac). in this study, we extensively analyzed the regulatory mechanisms of tfox(vc), encoding an activator protein for the chitin-induced competence. using a chromosomal tfox(vc)-lacz reporter system, we showed that a disaccharide of chitin, (glcnac)(2), at least was needed to activate both the transcription and translation of tfox(vc). ...201020302923
regulation of hemagglutinin/protease expression by the vars/vara-csra/b/c/d system in vibrio cholerae.in this study, through the analysis of vibrio cholerae 2740-80 mutant strains produced by the cholera toxin subunit b gene containing mariner-based transposon, we found that disruption of the vars gene, a member of the recently reported sensory system vars/vara-csra/b/c/d, resulted in altered expression of hemagglutinin/protease a. to further investigate the connection between vars and hapa, we generated an additional vars mutant, v. cholerae 2740-80-vs, and examined the effect of this mutation ...201020307644
[preparation of a 96-microwell plate dna diagnostic chip for detection of foodborne bacteria and its application in an incident of food poisoning].to develop a 96-microwell plate dna diagnostic chip for simultaneous detection of 9 major foodborne bacteria.201020335099
virulence profile and clonal relationship among the vibrio cholerae isolates from ground and surface water in a cholera endemic area during rainy season.all the v. cholerae non-o1, non-o139 isolates from ground and surface water samples collected during the rainy season (rainfall contributes significantly in the spread of cholera) contained ompw and a regulatory toxr gene, while many others possessed accessory cholera toxin (ace), hemolysin (hlya) and outer membrane protein (ompu) genes. all the isolates lacked ctxab, tcp, zot, rfbo1 and rfbo139 genes. the strains could be grouped into two main clusters colligating the isolates from ground water ...201020336507
temperature and ph affect the production of bacterial biofilm.the effect of different cultivation temperatures (30 and 37 degrees c) and ph of the media (5.5, 7.5, 8.5) on the biofilm production was compared in pseudomonas aeruginosa, klebsiella pneumoniae, and vibrio cholerae non-o1 and o1 using the crystal-violet test for estimation of quantitative production of the biofilm. decrease (46.4-98.4 %) in the biofilm production was observed at 37 degrees c in 8 of the tested strains (p. aeruginosa three strains, k pneumoniae two, v. cholerae non-o1 two, and v ...201020336508
[antimicrobial activity of morinda morindoides on in vitro growth of vibrio cholerae in côte d'ivoire].cholera is a major public health problem in developing countries. as a contribution to management of this disease, the study described herein was carried out in côte d'ivoire. the purpose was to evaluate the antibacterial activity of products obtained by various techniques from the leaves of morinda morindoides on a pathogenic strain of vibrio cholerae o:1. morinda morindoides is a medicinal plant in the ivorian pharmacopoeia. the products were obtained as aqueous extracts, 70% ethanolic extract ...201020337116
capsaicin, a potential inhibitor of cholera toxin production in vibrio cholerae.the use of natural compounds as inhibitory agents for virulence factor production is a new approach to overcome increased antimicrobial resistance in pathogenic bacteria. in this study, we examined whether red chilli (capsicum annuum) contains any such compound(s) that can repress the cholera toxin (ct) production in vibrio cholerae. we found that the methanol extract of red chilli could inhibit ct production in recently emerged v. cholerae o1 el tor variant strains without affecting their viabi ...201020337712
presence of typical and atypical virulence genes in vibrio isolates belonging to the harveyi clade.the study was aimed at investigating the presence of typical and atypical virulence genes in isolates belonging to the harveyi clade (vibrio harveyi and vibrio campbellii).201020345385
genome sequence of hybrid vibrio cholerae o1 mj-1236, b-33, and cirs101 and comparative genomics with v. cholerae.the genomes of vibrio cholerae o1 matlab variant mj-1236, mozambique o1 el tor variant b33, and altered o1 el tor cirs101 were sequenced. all three strains were found to belong to the phylocore group 1 clade of v. cholerae, which includes the 7th-pandemic o1 el tor and serogroup o139 isolates, despite displaying certain characteristics of the classical biotype. all three strains were found to harbor a hybrid variant of ctxphi and an integrative conjugative element (ice), leading to their establi ...201020348258
pathogenic vibrio activate nlrp3 inflammasome via cytotoxins and tlr/nucleotide-binding oligomerization domain-mediated nf-kappa b signaling.vibrio vulnificus and vibrio cholerae are gram-negative pathogens that cause serious infectious disease in humans. the beta form of pro-il-1 is thought to be involved in inflammatory responses and disease development during infection with these pathogens, but the mechanism of beta form of pro-il-1 production remains poorly defined. in this study, we demonstrate that infection of mouse macrophages with two pathogenic vibrio triggers the activation of caspase-1 via the nlrp3 inflammasome. activati ...201020348425
cholera outbreak, laos, 2007. 201020350415
chemiluminescent detect of e. coli o157:h7 using immunological method based on magnetic nanoparticles.the system of chemiluminescent magnetic enzyme-linked immunoassay was developed. e. coli o157:h7 was sandwiched between rabbits anti-e. coli o157:h7 polyclonal antibody-coated magnetic nanoparticles (immunomagnetic nanoparticles or imnps) and mouse anti-e. coli o157:h7 monoclonal antibody. commercial alkaline phosphatase conjugated horse anti-mouse immunoglobulin (alp-ab) was used to bind with the monoclonal antibody, finally the chemiluminescent signals were detected by adding 3-(2'-spiroadaman ...201020352706
design of a multiplex pcr assay for the simultaneous detection and confirmation of neisseria gonorrhoeae.to improve the detection of neisseria gonorrhoeae by designing a multiplex pcr assay using two n gonorrhoeae-specific genes as targets, thereby providing detection and confirmation of a positive result simultaneously.201020360139
prenylated pterocarpans as bacterial neuraminidase inhibitors.during the course of a neuraminidase inhibitor screening program on natural products, four new (6, 8, 11, and 12) and eleven known (1-5, 7, 9-10, and 13-15) pterocarpan derivatives were isolated as active principles from the etoac extract of the stem bark of erythrina abyssinica. their structures were identified by spectroscopic data analyses. all isolates exhibited significant inhibitory effects on the neuraminidases from clostridium perfringens and vibrio cholerae with ic(50) values ranging fr ...201020363636
[simultaneous detection of vibrio cholerae o1 and o139 by real-time quantitative pcr].targeting the specific o-antigen gene cluster, a taq-man real-time fluorescence pcr assay was developed to detect 01 and o139 vibrio cholera concurrently and avoid frequently occurred false positives.201020364601
determination of several potential virulence factors in non-o1 vibrio cholerae, pseudomonas aeruginosa, faecal coliforms and streptococci isolated from marrakesh groundwater.the dynamic, hemolytic and hemagglutination activities and the antibiotic resistance of non-o1 vibrio cholerae, pseudomonas aeruginosa, faecal coliforms (fc) and faecal streptococci (fs), isolated by standard membrane filtration methods from suburban and rural groundwater supplies, were carried out. detectable non-o1 v. cholerae and p. aeruginosa was present in 81% and 88% of samples. the total occurrence of fc and fs during the period of study was 94%. the annual average densities of non-o1 v. ...201020371949
cholera - recommendations for prevention in travellers.this article about cholera is part of our travel medicine series for 2010, providing a summary of prevention strategies and vaccination for infections that may be acquired by travellers. the series aims to provide practical strategies to assist general practitioners in giving travel advice, as a synthesis of multiple information sources which must otherwise be consulted. cholera is a severe diarrhoeal disease associated with worldwide pandemics. it affects vulnerable populations who lack adequat ...201020372681
enhanced stereoselectivity of alpha-mannosylation under thermodynamic control using trichloroacetimidates.o-specific polysaccharides of vibrio cholerae o1, serotypes inaba and ogawa, consist of alpha-(1-->2)-linked n-(3-deoxy-l-glycero-tetronyl)perosamine (4-amino-4,6-dideoxy-d-mannose). the blockwise synthesis of larger fragments of such o-pss involves oligosaccharide glycosyl donors that contain a nonparticipating 2-o-glycosyl group at the position vicinal to the anomeric center where the new glycosidic linkage is formed. such glycosyl donors may bear at c-4 either a latent acylamino (e.g., azido) ...201020381793
bacterial gene regulation by alpha-hydroxyketone signaling.bacteria produce diffusible, small signaling molecules termed autoinducers to promote cell-cell communication. recently, a novel class of signaling molecules, the alpha-hydroxyketones (ahks), was discovered in the facultative human pathogens legionella pneumophila and vibrio cholerae. in this review, we summarize and compare findings on ahk signaling in these bacteria. the l. pneumophila lqs (legionella quorum sensing) and v. cholerae cqs (cholera quorum sensing) gene clusters synthesize and det ...201020382022
vttra and vttrb encode toxr family proteins that mediate bile-induced expression of type three secretion system genes in a non-o1/non-o139 vibrio cholerae strain.strain am-19226 is a pathogenic non-o1/non-o139 serogroup vibrio cholerae strain that does not encode the toxin-coregulated pilus or cholera toxin but instead causes disease using a type three secretion system (t3ss). two genes within the t3ss pathogenicity island, herein named vttr(a) (locus tag a33_1664) and vttr(b) (locus tag a33_1675), are predicted to encode proteins that show similarity to the transcriptional regulator toxr, which is found in all strains of v. cholerae. strains with a dele ...201020385759
marine biofilms on submerged surfaces are a reservoir for escherichia coli and vibrio cholerae.the enteric bacterium and potential human pathogen, escherichia coli, is known to persist in tropical soils and coastal waters. vibrio cholerae causes the disease cholera and inhabits marine environments including microbial films on submerged surfaces. the abundances of e. coli and v. cholerae were quantified in biofilm and water-column samples from three harbors in honolulu, hawai'i, which differ in their local and international ship traffic. e. coli and, in some cases v. cholerae, occurred in ...201020390555
amino-terminal residues dictate the export efficiency of the campylobacter jejuni filament proteins via the flagellum.bacterial flagella play an essential role in the pathogenesis of numerous enteric pathogens. the flagellum is required for motility, colonization, and in some instances, for the secretion of effector proteins. in contrast to the intensively studied flagella of escherichia coli and salmonella typhimurium, the flagella of campylobacter jejuni, helicobacter pylori and vibrio cholerae are less well characterized and composed of multiple flagellin subunits. this study was performed to gain a better u ...201020398207
the phosphoenolpyruvate phosphotransferase system regulates vibrio cholerae biofilm formation through multiple independent pathways.the bacterial phosphoenolpyruvate phosphotransferase system (pts) is a highly conserved phosphotransfer cascade that participates in the transport and phosphorylation of selected carbohydrates and modulates many cellular functions in response to carbohydrate availability. it plays a role in the virulence of many bacterial pathogens. components of the carbohydrate-specific pts include the general cytoplasmic components enzyme i (ei) and histidine protein (hpr), the sugar-specific cytoplasmic comp ...201020400550
a direct nmr method for the measurement of competitive kinetic isotope effects.we present a technique that uses (13)c nmr spectroscopy to measure kinetic isotope effects on the second-order rate constant (k(cat)/k(m)) for enzyme-catalyzed reactions. using only milligram quantities of isotopically labeled substrates, precise competitive kies can be determined while following the ongoing reaction directly in a nmr spectrometer. our results for the vibrio cholerae sialidase-catalyzed hydrolysis of natural substrate analogs support a concerted enzymatic transition state for th ...201020418878
secretory iga-mediated protection against v. cholerae and heat-labile enterotoxin-producing enterotoxigenic escherichia coli by rice-based vaccine.cholera and enterotoxigenic escherichia coli (etec) are among the most common causes of acute infantile gastroenteritis globally. we previously developed a rice-based vaccine that expressed cholera toxin b subunit (mucorice-ctb) and had the advantages of being cold chain-free and providing protection against cholera toxin (ct)-induced diarrhea. to advance the development of mucorice-ctb for human clinical application, we investigated whether the ctb-specific secretory iga (siga) induced by mucor ...201020421480
high hopes for oral cholera vaccine. 201020428379
from endotoxin to exotoxin: de's rich legacy to cholera.between 1951 and 1959, sambhu nath de made crucial discoveries on the pathogenesis of cholera that changed the course of our understanding of the disease. the discovery that cholera is caused by a potent exotoxin (cholera enterotoxin) affecting intestinal permeability, the demonstration that bacteria-free culture filtrates of vibrio cholerae were enterotoxic, and the development of a reproducible animal model for the disease are considered milestones in the history of the fight against cholera. ...201020428396
occurrence and composition of class 1 and class 2 integrons in clinical and environmental o1 and non-o1/non-o139 vibrio cholerae strains from the brazilian amazon.this study identified and characterised class 1 and 2 integrons in clinical and environmental vibrio cholerae o1 and non-o1/non-o139 strains isolated from the brazilian amazon. the aada2 and aada7 gene cassettes were found in class 1 integrons in two genotypes of environmental v. cholerae non-o1/non-o139. empty integrons were found in strains from the brazilian cholera epidemic. a class 2 integron was detected in one strain from the v. cholerae amazonia lineage harbouring sat1 and aada1 genes. a ...201020428687
a functional carbohydrate chip platform for analysis of carbohydrate-protein interaction.a carbohydrate chip based on glass or other transparent surfaces has been suggested as a potential tool for high-throughput analysis of carbohydrate-protein interactions. here we proposed a facile, efficient, and cost-effective method whereby diverse carbohydrate types are modified in a single step and directly immobilized onto a glass surface, with retention of functional orientation. we modified various types of carbohydrates by reductive amination, in which reducing sugar groups were coupled ...201020431189
spectroscopic and thermodynamic comparisons of escherichia coli dna photolyase and vibrio cholerae cryptochrome 1.escherichia coli dna photolyase and cryptochrome 1 isolated from vibrio cholerae, a member of the cry-dash family, are directly compared using a variety of experimental methods including uv-vis and raman spectroscopy, reduction potential measurements, and isothermal titration calorimetry. the semiquinone form of the cryptochrome has an absorption spectrum that is red-shifted from that of the photolyase, but the raman spectrum indicates that the fad binding pocket is similar to that of photolyase ...201020438097
a cholera outbreak of the vibrio cholerae o1 el tor variant carrying classical ctxb in northeastern thailand in 2007.cholera outbreaks occurred in thailand in 2007. isolates from the northeastern regions were analyzed. interestingly, the outbreak strain was identified as biotype el tor; serotype ogawa with cholera toxin b subunit gene (ctxb) of the classical type and ctx prophage repressor gene of the el tor type. the clone was genetically closely related to pulsotype h, which is predominantly found in india. it was probably introduced into thailand recently.201020439970
growth and laboratory maintenance of vibrio cholerae.vibrio cholerae is a gram-negative enteric pathogen. this unit includes protocols for the growth and maintenance of v. cholerae in the laboratory.201020440684
size and dynamics of the vibrio cholerae porins ompu and ompt probed by polymer exclusion.the trimeric ompu and ompt porins form large, triple-barrel hydrophilic channels in the outer membrane of the pathogen vibrio cholerae. they have distinct pore properties, such as conductance, block by deoxycholic acid, and sensitivity to acidic ph. their three-dimensional structures are unknown, but they share significant sequence homologies. to gain insight into the molecular basis for the distinct functional properties of these two similar porins, we carried out polymer exclusion experiments ...201020441745
mining regulatory 5'utrs from cdna deep sequencing datasets.regulatory 5' untranslated regions (r5'utrs) of mrnas such as riboswitches modulate the expression of genes involved in varied biological processes in both bacteria and eukaryotes. new high-throughput sequencing technologies could provide powerful tools for discovery of novel r5'utrs, but the size and complexity of the datasets generated by these technologies makes it difficult to differentiate r5'utrs from the multitude of other types of rnas detected. here, we developed and implemented a bioin ...201019969537
synthesis, spectral analysis and in vitro microbiological evaluation of 3-(3-alkyl-2,6-diarylpiperin-4-ylidene)-2-thioxoimidazolidin-4-ones as a new class of antibacterial and antifungal agents.in the present work, a new series of bis hybrid heterocycle comprising both piperidine and thiohydantoin nuclei together namely 3-(3-alkyl-2,6-diarylpiperin-4-ylidene)-2-thioxoimidazolidin-4-ones 46-60 was synthesized by the treatment of the respective thiosemicarbazones 31-45 with chloroethyl acetate and anhydrous sodium acetate in refluxing ethanol for 4h and were characterized by melting point, elemental analysis, ms, ft-ir, one-dimensional nmr ((1)h, d(2)o exchanged (1)h and (13)c), two dime ...201020004098
classical rs1 and environmental rs1 elements in vibrio cholerae o1 el tor strains harbouring a tandem repeat of ctx prophage: revisiting mozambique in 2005.currently, vibrio cholerae o1 serogroup biotype el tor strains producing classical type cholera toxin (altered strains or el tor variants) are prevalent in asia and in mozambique. mozambican strains collected in 2004 contained a tandem repeat of ctx prophage on the small chromosome and each ctx prophage harboured the classical rstr and classical ctxb. we found that the majority of the strains collected in 2005 in mozambique contained extra elements on the large chromosome in addition to the tand ...201020007761
isolation of a bacteriophage specific for cs7-expressing strains of enterotoxigenic escherichia coli.enterotoxigenic escherichia coli (etec) is the most common bacterial cause of childhood diarrhoea in bangladesh. among the virulence factors of etec, toxins and colonization factors (cfs) play a major role in pathogenesis. unlike vibrio cholerae, the relationship between etec and etec-specific phages is poorly understood and the possible role of etec phages in the evolution of etec strains in the environment is yet to be established. this study was designed specifically to isolate phages that ar ...201020007763
structure and mechanism of a pentameric formate channel.formate transport across the inner membrane is a critical step in anaerobic bacterial respiration. members of the formate/nitrite transport protein family function to shuttle substrate across the cytoplasmic membrane. in bacterial pathogens, the nitrite transport protein is involved in protecting bacteria from peroxynitrite released by host macrophages. we have determined the 2.13-a structure of the formate channel foca from vibrio cholerae, which reveals a pentamer in which each monomer possess ...201020010838
polymerase chain reaction-based detection of total and specific vibrio species.the polymerase chain reaction (pcr) technique is widely used for efficient detection of food-borne pathogens because of speed and specificity. however, pcr methods have focused mostly on species-specific detection. in the present work, we describe a pcr-based method for the simultaneous detection of all vibrio species because lots of them are notorious food-borne human pathogens. we then combined this total detection method with specific detection of vibrio cholerae pathogen. using a degenerate ...201019937156
antimicrobial lipids from the hemolymph of brachyuran crabs.the potential of marine crabs as a source of biologically active products is largely unexplored. in the present study, antimicrobial activity of the hemolymph (plasma) and hemocytes (plasma cells) of six brachyuran crabs was investigated against 16 pathogenic strains. among the 16 strains tested maximum zone of inhibition was recorded in the hemolymph of hyas araneus against shigella flexineri. interestingly staphylococcus aureus and salmonella typhi were susceptible to all the hemolymph and hem ...201019937399
preparation of synthetic polyoxazoline based carrier and vibrio cholerae o-specific polysaccharide conjugate vaccine.multiple chemical attachments of carbohydrate antigens to linear polymer represent promising technique for creating biologically effective conjugates. a novel conjugate consisting of detoxified lipopolysaccharide of vibrio cholerae o135, linear polymer (polyoxazoline copolymer, serving as a matrix) and bsa (as immunogenic protein), has been prepared. the reaction conditions were optimized for obtaining high degree of conjugation. analytical methods were evaluated to characterize conjugates obtai ...201019939517
rtxa1-induced expression of the small gtpase rac2 plays a key role in the pathogenicity of vibrio vulnificus.infection with the human pathogen vibrio vulnificus leads to the generation of reactive oxygen species (ros) via nad(p)h oxidase (nox) in host cells. in the present study, we employed mutant v. vulnificus strains to identify an essential virulence factor responsible for this ros generation. we found that repeats-in-toxin a1 (rtxa1) expressed by v. vulnificus acts via nox1 to induce significant ros generation in the intestine epithelial cells, which ultimately results in cell death. furthermore, ...201019919301
the toxt-dependent methyl-accepting chemoreceptors acfb and tcpi contribute to vibrio cholerae intestinal colonization.vibrio cholerae colonizes the human intestine and causes the acute diarrheal disease cholera. flagellar-mediated chemotaxis contributes to intestinal colonization as well as infectivity. the virulence-regulatory protein toxt activates transcription of the genes encoding the major virulence factors cholera toxin and toxin coregulated pilus. toxt additionally activates transcription of two genes, tcpi and acfb, located within the vibrio pathogenicity island predicted to encode methyl-accepting che ...201019929967
triclosan resistance of pseudomonas aeruginosa pao1 is due to fabv, a triclosan-resistant enoyl-acyl carrier protein reductase.triclosan, a very widely used biocide, specifically inhibits fatty acid synthesis by inhibition of enoyl-acyl carrier protein (acp) reductase. escherichia coli fabi is the prototypical triclosan-sensitive enoyl-acp reductase, and e. coli is extremely sensitive to the biocide. however, other bacteria are resistant to triclosan, because they encode triclosan-resistant enoyl-acp reductase isozymes. in contrast, the triclosan resistance of pseudomonas aeruginosa pao1 has been attributed to active ef ...201019933806
the virulence transcriptional activator apha enhances biofilm formation by vibrio cholerae by activating expression of the biofilm regulator vpst.vibrio cholerae is the agent of the severe diarrheal disease cholera, and it perpetuates in aquatic reservoirs when not in the host. within the host's intestines, the bacteria execute a complex regulatory pathway culminating with the production of virulence factors that allow colonization and cause disease. the ability of v. cholerae to form biofilms is thought to aid its persistence in the aquatic environment and passage through the gastric acid barrier of the stomach. the transcriptional activ ...201019933826
the phob regulatory system modulates biofilm formation and stress response in el tor biotype vibrio cholerae.the phobr regulatory system is required for the induction of multiple genes under conditions of phosphate limitation. here, we examine the role of phob in biofilm formation and environmental stress response in vibrio cholerae of the el tor biotype. deletion of phob or hapr enhanced biofilm formation in a phosphate-limited medium. planktonic and redispersed biofilm cells of the deltaphob mutant did not differ from wild type for the expression of hapr, suggesting that phob negatively affects biofi ...201019909344
validation of a method for the detection of five species, serogroups, biotypes and virulence factors of vibrio by multiplex pcr in fish and seafood.in this work a sequential multiplex pcr system was designed and validated for the detection of most frequent foodborne pathogen vibrio species in fish and seafood (vibrio cholerae, vibrio parahaemolyticus, vibrio vulnificus, vibrio alginoliticus and vibrio mimicus). the method proposed functions in a hierarchical way, being composed of an end-point multiplex pcr to detect the presence of dna belonging to the studied species, followed by multiplex pcr and fragment analysis allowing the viability ...201019913702
characterization of two novel gene cassettes, dfra27 and aada16, in a non-o1, non-o139 vibrio cholerae isolate from china.two novel integron-borne cassettes, dfra27 (encoding trimethoprim resistance) and aada16 (encoding streptomycin and spectinomycin resistance), located on a conjugative plasmid, have been found in a non-o1, non-o139 vibrio cholera isolate. dfra27 shares 75% amino acid identity with dfra5, and aada16 shares 88% identity with adaa6. cloning of the cassette region and expression analysis demonstrated that the aada16 gene can be expressed from its own promoter sequence, which is present upstream of t ...201019906273
construction and characterization of rtxa and rtxc mutants of auxotrophic o139 vibrio cholerae.vibrio cholerae is a gram-negative bacterium that causes diarrheal disease. v. cholerae o1 and o139 serogroups are toxigenic and are known to cause epidemic cholera. these serogroups produce cholera toxin and other accessory toxins such as accessory cholera enterotoxin, zonula occludens toxin, and multifunctional, autoprocessing repeat in toxin (martx). in the present study, we incorporated mutated rtxa and rtxc genes that encode martx toxin into the existing aminolevulinic acid (ala) auxotrophi ...201019900531
novel pcr-based genotyping method, using genomic variability between repetitive sequences of toxigenic vibrio cholerae o1 el tor and o139.a novel genotyping method for toxigenic vibrio cholerae o1 el tor and o139 was developed. the method was designed to amplify dna sequences "sandwiched" between any given pair of repetitive sequences, "v. cholera repeats (vcr)", in highly polymorphic "integron island" of ca. 125 kb in the small chromosome of toxigenic v. cholerae so that the resultant pcr amplicons would present with a strain-specific electrophoretic pattern. the vcr-targeted pcr assay (vcr-pcr) for 37 strains of toxigenic v. cho ...201019900536
synthesis of silver nanoparticles using acalypha indica leaf extracts and its antibacterial activity against water borne pathogens.in the present study, biosynthesis of silver nanoparticles and its activity on water borne bacterial pathogens were investigated. silver nanoparticles were rapidly synthesized using leaf extract of acalypha indica and the formation of nanoparticles was observed within 30min. the results recorded from uv-vis spectrum, scanning electron microscopy (sem), x-ray diffraction (xrd) and energy dispersive spectroscopy (eds) support the biosynthesis and characterization of silver nanoparticles. from high ...201019896347
development of a live oral attaching and effacing escherichia coli vaccine candidate using vibrio cholerae cvd 103-hgr as antigen vector.attaching and effacing escherichia coli (aeec) share the ability to induce pedestal formation and intimate adherence of the bacteria to the intestinal epithelial cell and effacement of microvilli of epithelial tissue. the locus of enterocyte effacement (lee) pathogenicity island encodes the ability to induce attaching and effacing (a/e) lesions and contains the gene eae, which encodes intimin, an outer membrane protein that is an adhesin for a/e lesion formation. here we show the utility of usin ...201019878715
comparison of clinical features and immunological parameters of patients with dehydrating diarrhoea infected with inaba or ogawa serotypes of vibrio cholerae o1.vibrio cholerae o1, ogawa and inaba serotypes, both cause severe cholera. we compared clinical and immunological features in patients in bangladesh infected with these 2 serotypes. blood was collected from hospitalized ogawa (n=146) or inaba (n=191) patients at the acute stage (day 2) and 5 and 19 days later. ogawa patients were younger than inaba, presented with shorter duration of diarrhoea, and had more frequent abdominal pain, vomiting and need for intravenous fluids (p<0.05). inaba patients ...201019883159
beyond antibiotic resistance: integrating conjugative elements of the sxt/r391 family that encode novel diguanylate cyclases participate to c-di-gmp signalling in vibrio cholerae.in vibrio cholerae, the second messenger bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-gmp) increases exopolysaccharides production and biofilm formation and decreases virulence and motility. as such, c-di-gmp is considered an important player in the transition from the host to persistence in the environment. c-di-gmp level is regulated through a complex network of more than 60 chromosomal genes encoding predicted diguanylate cyclases (dgcs) and phosphodiesterases. herein we report th ...201019888998
simultaneous differential detection of human pathogenic and nonpathogenic vibrio species using a multiplex pcr based on gyrb and pnta genes.to develop a multiplex pcr targeting the gyrb and pnta genes for vibrio species differentiation.201019891709
three-dimensional structure of different functional forms of the vibrio cholerae hemolysin oligomer: a cryo-electron microscopic study.vibrio cholerae hemolysin (hlya) is a 65-kda water-soluble pore-forming toxin that causes lysis of eukaryotic cells by destroying selective permeability of the plasma membrane bilayer. the hlya monomer self-assembles on the target cell surface to the more stable beta-barrel amphipathic heptamer, which inserts into the membrane bilayer to form a diffusion channel. deletion of the 15-kda beta-prism lectin domain at the c terminus generates a 50-kda hemolysin variant (hlya50) with an approximately ...201019854900
development of immunoglobulin m memory to both a t-cell-independent and a t-cell-dependent antigen following infection with vibrio cholerae o1 in bangladesh.vibrio cholerae o1 can cause severe watery diarrhea that can be life-threatening without treatment. infection results in long-lasting protection against subsequent disease. development of memory b cells of the immunoglobulin g (igg) and iga isotypes to v. cholerae o1 antigens, including serotype-specific lipopolysaccharide (lps) and the b subunit of cholera toxin (ctb), after cholera infection has been demonstrated. memory b cells of the igm isotype may play a role in long-term protection, parti ...201019858296
quorum sensing negatively regulates hemolysin transcriptionally and posttranslationally in vibrio cholerae.recent work has shown that in addition to cholera toxin (ct) and the toxin-coregulated pilus (tcp), other cytotoxic proteins in vibrio cholerae also cause disease symptoms, and this is particularly evident in strains lacking ct. one such protein is the hemolysin encoded by hlya. here we show that, like ct and tcp, hlya is repressed by the quorum-sensing-regulated transcription factor hapr. this repression occurs on two levels: one at the transcriptional level that is independent of the metallopr ...201019858311
on the origins of a vibrio species.thirty-two genome sequences of various vibrionaceae members are compared, with emphasis on what makes v. cholerae unique. as few as 1,000 gene families are conserved across all the vibrionaceae genomes analysed; this fraction roughly doubles for gene families conserved within the species v. cholerae. of these, approximately 200 gene families that cluster on various locations of the genome are not found in other sequenced vibrionaceae; these are possibly unique to the v. cholerae species. by comp ...201019830476
vej{phi}, a novel filamentous phage of vibrio cholerae able to transduce the cholera toxin genes.a novel filamentous bacteriophage, designated vejphi, was isolated from strain mo45 of vibrio cholerae of the o139 serogroup. a molecular characterization of the phage was carried out, which included sequencing of its whole genome, study of the genomic structure, identification of the phage receptor, and determination of the function of some of the genes, such as those encoding the major capsid protein and the single-stranded dna-binding protein. the genome nucleotide sequence of vejphi, which c ...201019833774
rapid detection of virulence-associated genes in environmental strains of vibrio cholerae by multiplex pcr.vibrio cholerae, the causative agent of cholera is ubiquitously distributed in aquatic environment particularly in coastal waters, estuaries, and rivers. in the present investigation, a multiplex pcr assay was developed for the detection of virulence-associated genes (rtxa, tcpa, ctxa, hlya, and sto) in environmental isolates of v. cholerae. a total of 90 strains isolated from different environmental sources were screened for the presence of virulence-associated genes. our results showed that th ...201019841974
rapid and sensitive detection of vibrio cholerae by loop-mediated isothermal amplification targeted to the gene of outer membrane protein ompw.the present study was aimed to develop a loop-mediated isothermal amplification (lamp) assay for rapid and specific detection of vibrio cholerae.201019874480
acanthamoeba polyphaga is a possible host for vibrio cholerae in aquatic environments.acanthamoeba is a genus of free-living amoebae found to be able to host many bacterial species living in the environment. acanthamoebae and vibrio cholerae are found in the aquatic environments of cholera endemic areas. previously it has been shown that v. cholerae o1 and o139 can survive and grow in acanthamoeba castellanii. the aim of this study was to examine the ability of acanthamoeba polyphaga to host v. cholerae o1 and o139. the interaction between a. polyphaga and v. cholerae strains was ...201019815016
a rapid, simple, and sensitive loop-mediated isothermal amplification method to detect toxigenic vibrio cholerae in rectal swab samples.loop-mediated isothermal amplification (lamp) method was designed for clinical diagnosis of vibrio cholerae carrying the ctxa gene. the detection limits of the method were 5 fg of purified genomic dna/reaction and 0.54 cfu/reaction. the method was applied to rectal swab samples from cholera patients and healthy volunteers (19 subjects each) and yielded the same results as the "gold standard" culture method, while the polymerase chain reaction-based method failed to detect v. cholerae in 8 of the ...201019815364
vibrio cholerae o1 ogawa detoxified lipopolysaccharide structures as inducers of cytokines and oxidative species in macrophages.multidrug resistance in several strains of vibrio cholerae has encouraged anti-cholera vaccine developmental attempts using various subcellular moieties. in order to examine the immunological efficacy of detoxified lps (dlps)-derived saccharide immunogens, ex vivo activation of mouse peritoneal macrophages (mphis) was investigated. the immunomodulatory effect was evaluated via induction of the pro-inflammatory cytokines tumour necrosis factor-alpha, interleukin (il)-1 alpha and il-6 and accelera ...201019815665
epidemics of severe cholera caused by el tor vibrio cholerae o1 ogawa possessing the ctxb gene of the classical biotype in orissa, india.we investigated the epidemic of cholera that occurred in kashipur and dasmantpur blocks of orissa, reported during july-september 2007.201019781971
molecular evidence favouring step-wise evolution of mozambique vibrio cholerae o1 el tor hybrid strain.the ctxab operon, encoding cholera toxin (ct) in vibrio cholerae, is carried by the genome of a filamentous phage, ctxphi. usually, specific ctxphi infect each of the two important biotypes, classical and el tor, of epidemic v. cholerae strains belonging to serogroup o1, and are called ctx(class)phi and ctx(et)phi, respectively. however, an unusual hybrid el tor strain carrying ctx(class)phi caused the cholera epidemic in mozambique in 2004. to understand the evolution of that strain, we have fu ...201019797359
meiotic recombination between two polymorphic restriction sites within the beta globin gene cluster.analysis of beta globin gene haplotypes for prenatal diagnosis of beta thalassaemia has revealed a recombination event within the beta globin gene cluster. both a change in the avaii polymorphic site within the beta globin gene and a change in the phenotype of the beta globin gene were observed. paternity was established by the pedigree analysis of hypervariable 'minisatellite' dna polymorphisms and the most probable explanation of the recombination event is a crossover between the psi beta glob ...20103005579
[193 cases of gastroschisis and omphalocele--postoperative results].treatment was applied to 97 cases of omphalocele and 96 cases of gastroschisis at the dortmund department of paediatric surgery over the past 20 years. the survival rate was 122. follow-up checks were recently applied to 56 of those former patients, after nearly ten years had elapsed from surgery. thirty-eight of these patients were clinically examined, while questionnaires were completed for the rest. primary closures had been performed on 50 per cent of the cases, while the defects in the othe ...20102966527
segregation analysis of juvenile myoclonic epilepsy.we examined the inheritance of juvenile myoclonic epilepsy (jme). we looked at both the trait of "epilepsy" and the trait of "epilepsy-plus-eeg abnormalities," since eeg abnormalities are frequently found in the clinically unaffected sibs of jme patients. we tested several modes of inheritance including the fully penetrant recessive and several two-locus models. we could reject all models tested (fully penetrant single-locus and two-locus models) when abnormal eegs were classified as "unaffected ...20103136050
possible role of insulin deficiency and growth hormone in severe retinopathy. 20102863521
stress induced right ventricular dysfunction: an indication of reversible right ventricular ischaemia.stress induced changes in left ventricular ejection fraction are widely used in the detection and assessment of coronary artery disease. this study demonstrates that right ventricular dysfunction may also occur, and assesses its significance in terms of coronary artery anatomy. this study involved 14 normal subjects and 26 with coronary artery disease investigated by equilibrium radionuclide ventriculography, at rest and during maximal dynamic exercise. mean normal resting right ventricular ejec ...20103032637
stress induced right ventricular dysfunction: an indication of reversible right ventricular ischaemia.stress induced changes in left ventricular ejection fraction are widely used in the detection and assessment of coronary artery disease. this study demonstrates that right ventricular dysfunction may also occur, and assesses its significance in terms of coronary artery anatomy. this study involved 14 normal subjects and 26 with coronary artery disease investigated by equilibrium radionuclide ventriculography, at rest and during maximal dynamic exercise. mean normal resting right ventricular ejec ...20103032637
[clinical interpretation of retinal circulatory measurements. i. technical measurement possibilities and clinical interpretation aid].the present possibilities to measure blood flow and other magnitudes of retinal microcirculation in vivo are discussed. on this basis, a simple model designed for retinal microcirculation is presented as a tool for the clinical interpretation of measuring results. based on the experience of over 200 measurements of retinal microcirculation magnitudes, subsequent reports give a clinical interpretation of measuring results, utilizing the measuring models presented. thus, it is intended to demonstr ...20102950360
[despair. a psychopathological study (3)]. 20103836585
left ventricular diastolic dysfunction: early diastolic relaxation and late diastolic compliance. 20102913111
isolated duodenal tamponade for treatment of bleeding duodenal ulcer. 20102895833
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