| endotoxins of enteric pathogens are chemotactic factors for human neutrophils. | early activation of human peripheral blood polymorphonuclear neutrophils is characterized by their morphological changes from spherical to polarized shapes. the endotoxins from enteric pathogens (s. dysenteriae type 1, v. cholerae inaba 569b, s. typhimurium, and k. pneumoniae) were assessed by their ability to induce morphological polarization of the neutrophils as measures of early activation. phagocytic activity, adhesion, chemokinetic locomotion, and nitroblue tetrazolium (nbt) dye-reduction ... | 2002 | 12359090 |
| the global regulator arca modulates expression of virulence factors in vibrio cholerae. | a vibrio cholerae arca mutant was constructed and used to examine the role of the global anaerobiosis response regulator arca in the expression of virulence factors in this important human pathogen. in v. cholerae, expression of the major virulence factors cholera toxin (ct) and toxin-coregulated pilus (tcp) is regulated by the transcriptional activator toxt. toxt expression, in turn, is controlled by the transmembrane dna binding proteins toxr and tcpp. in the v. cholerae arca mutant, although ... | 2003 | 14500477 |
| molecular cloning and characterization of an abc multidrug efflux pump, vcam, in non-o1 vibrio cholerae. | a gene responsible for multidrug resistance was cloned from the chromosomal dna of non-o1 vibrio cholerae nctc 4716 by using as a host drug-hypersensitive escherichia coli strain kam32, which lacks major multidrug efflux pumps. e. coli cells transformed with the gene showed elevated levels of resistance to a number of structurally dissimilar drugs, such as tetracycline, norfloxacin, ciprofloxacin, doxorubicin, daunomycin, 4',6-diamidino-2-phenylindole, and hoechst 33342. we determined the nucleo ... | 2003 | 12878498 |
| csra and three redundant small rnas regulate quorum sensing in vibrio cholerae. | bacteria communicate using a process called quorum sensing which involves production, secretion and detection of signalling molecules called autoinducers. quorum sensing allows populations of bacteria to simultaneously regulate gene expression in response to changes in cell density. the human pathogen, vibrio cholerae, uses a quorum-sensing circuit composed of parallel systems that transduce information through four redundant regulatory small rnas (srnas) called quorum regulatory rnas (qrr) to c ... | 2005 | 16262799 |
| comparative study of different methods for detection of toxic and other enzymatic factors in vibrio cholerae strains. | the purpose of this work was to characterize the toxin profile and the presence of other virulence factors involved in the pathogenesis and biology of 13 v. cholerae o1 (11 clinical cases and 2 waters) and 6 v. cholerae non o1 strains (4 clinical cases and 2 waters) using genetic (pcr), immunological (rpla), biochemical (nad degradation, haemolysis, kanagawa phenomenon, caseinase, lecithinase, mucinase, amylase, esculine hydrolysis) and cell culture (vero e6, hep-2) assays. the results indicated ... | 2004 | 16295321 |
| hyperinfectivity: a critical element in the ability of v. cholerae to cause epidemics? | cholera is an ancient disease that continues to cause epidemic and pandemic disease despite ongoing efforts to limit its spread. mathematical models provide one means of assessing the utility of various proposed interventions. however, cholera models that have been developed to date have had limitations, suggesting that there are basic elements of cholera transmission that we still do not understand. | 2006 | 16318414 |
| characterizing gene sets with funcassociate. | summary: funcassociate is a web-based tool to help researchers use gene ontology attributes to characterize large sets of genes derived from experiment. distinguishing features of funcassociate include the ability to handle ranked input lists, and a monte carlo simulation approach that is more appropriate to determine significance than other methods, such as bonferroni or idák p-value correction. funcassociate currently supports 10 organisms (vibrio cholerae, shewanella oneidensis, saccharomyces ... | 2003 | 14668247 |
| crystallographic analysis of the pseudomonas aeruginosa strain k122-4 monomeric pilin reveals a conserved receptor-binding architecture. | adherence of pathogens to host cells is critical for the initiation of infection and is thus an attractive target for anti-infective therapeutics and vaccines. in the opportunistic human pathogen pseudomonas aeruginosa, host-cell adherence is achieved predominantly by type iv pili. analysis of several clinical strains of p. aeruginosa reveals poor sequence conservation between pilin genes, including the residues in the receptor-binding site. interestingly, the receptor-binding sites appear to re ... | 2004 | 15350129 |
| a review of vaccine research and development: human enteric infections. | worldwide, enteric infections rank third among all causes of disease burden, being responsible for some 1.7-2.5 million deaths per year, mostly in young children and infants in developing countries. the main infectious agents responsible for human enteric infections include several viruses (enteric adenoviruses, astroviruses, human caliciviruses (hucv), rotaviruses (rv)) and several bacterial agents, such as campylobacter jejuni, a variety of pathogenic escherichia coli strains including enterot ... | 2006 | 16483695 |
| genetic diversity and antibiotic resistance of clinical and environmental vibrio cholerae suggests that many serogroups are reservoirs of resistance. | vibrio cholerae is an important human pathogen and the cause of cholera. since genetic variation and antibiotic resistance of strains have implications for effective treatment of the disease, we examined the genetic diversity and antibiotic resistance profile in 92 clinical strains (serogroup o1) and 56 environmental strains (o1 antigen, 42 strains; non-o1 antigen, 14 strains) isolated in brazil between 1991 and 1999. clinical and environmental o1 strains showed greater drug resistance compared ... | 2004 | 15473163 |
| the structure of the cytoplasmic domain of epsl, an inner membrane component of the type ii secretion system of vibrio cholerae: an unusual member of the actin-like atpase superfamily. | the type ii secretion system (t2ss) is used by several gram-negative bacteria for the secretion of hydrolytic enzymes and virulence factors across the outer membrane. in these secretion systems, a complex of 12-15 so-called "gsp proteins" spans from a regulatory atpase in the cytoplasm, via several signal or energy transducing proteins in the inner membrane and the pseudopilins in the periplasm, to the actual pore in the outer membrane. the human pathogen vibrio cholerae employs such an assembly ... | 2004 | 15533433 |
| vibrio cholerae persistence in aquatic environments and colonization of intestinal cells: involvement of a common adhesion mechanism. | forty-one tnpho a mutants of vibrio cholerae o1 classical strain cd81 were analyzed for their ability to interact with chitin particles, tigriopus fulvus copepods and the intestine 407 cell line compared to the parent strain. thirteen mutants were less adhesive than cd81; in particular, t21, t33 and t87 were less adhesive towards all substrates and insensitive to inhibition by n-acetyl glucosamine (glcnac). by sds-page analysis of sarkosyl-insoluble membrane proteins (simps) isolated from mutant ... | 2005 | 15766778 |
| [cloning and expression of vibrio cholerae zonula occludens toxin (zot) gene in escherichia coli]. | two recombinant plasmids containing the cloned pcr-amplifled vibrio cholerae zonula occludens toxin (zot) gene was constructed in orientation providing its transcription from lac-promoter. one of them contained also its own zot promoter. the third plasmid was obtained by subcloning a vibrio cholerae dna fragment including intact zot and ace (accessory cholera enterotoxin) genes. the expression levels of the cloned genes in escherichia coli varied depending on a promoter type, host strain and cul ... | 2005 | 15790030 |
| the sodium cycle in vibrio cholerae: riddles in the dark. | twenty years ago, v. p. skulachev put forward the revolutionary concept of the chemiosmotic sodium cycle which is an integral of the paradigm of modern bioenergetics. this fundamental concept stimulated studies in many areas and yielded plenty of sometimes quite unexpected (and thus most valuable) discoveries. in particular, variations of the sodium cycle have been found in a surprisingly large number of pathogenic microorganisms, raising the question about the possible link of sodium energetics ... | 2005 | 15807652 |
| [aspects of vibrio cholerae lipopolysaccharide]. | in this review information on the chemical structure, biosynthesis, antigenic and biological properties of v. cholerae lipopolysaccharide (lps) is presented. the specific structural feature of this lps is a small size of the polysaccharide chain of o-antigen. in vibrios of serogroup o 139 it is oligosaccharide. the modification of the o-chain (methylation of individual sugars, shortened chain, etc.) plays an essential role in the antigenic specificity of v. cholerae lps. all these factors affect ... | 2002 | 12043141 |
| in vivo induced clpb1 gene of vibrio cholerae is involved in different stress responses and affects in vivo cholera toxin production. | previously in global transcription profile approach one of the cosmid clones of vibrio cholerae containing the genes pnuc, icmf, and a fragment of clpb2 showed higher expression in v. cholerae grown inside rabbit intestine. in the present report, both the stress responsive clpb genes of v. cholerae o395 were cloned, clpb1 from chromosome i and clpb2 present in chromosome ii. from the northern blot hybridization it was observed that the level of transcription of clpb2 was very low which could be ... | 2005 | 15883026 |
| nasally administered cholera toxin a-subunit acts as a mucosal adjuvant. | it is well established that cholera toxin (ct) produced by vibrio cholerae acts as a potent mucosal adjuvant; however, the native form of this molecule causes severe diarrhea. furthermore, both native ct and its b-subunit derivative bind to monosialogangliosides (gm1) in membrane raft micro-domains on neural tissues and are thus unsuitable for use in humans. in this study, we evaluated the adjuvanticity of the ct a-subunit (ct-a) administered with ovalbumin (ova) by the nasal route. we found tha ... | 2003 | 12816361 |
| in vitro and in vivo antimicrobial activity of granulysin-derived peptides against vibrio cholerae. | to determine the antibacterial activity of synthetic peptides derived from the cationic antimicrobial peptide granulysin against vibrio cholerae. | 2008 | 18310138 |
| tcpf is a soluble colonization factor and protective antigen secreted by el tor and classical o1 and o139 vibrio cholerae serogroups. | vibrio cholerae causes diarrhea by colonizing the human small bowel and intoxicating epithelial cells. colonization is a required step in pathogenesis, and strains defective for colonization are significantly attenuated. the best-characterized v. cholerae colonization factor is the toxin-coregulated pilus (tcp). it has been demonstrated that tcp is required for v. cholerae colonization in both humans and mice. tcp enhances bacterial interactions that allow microcolony formation and thereby promo ... | 2005 | 16040956 |
| the escherichia coli bara-uvry two-component system is a virulence determinant in the urinary tract. | the salmonella enterica bara-sira, the erwinia carotovora exps-expa, the vibrio cholerae bara-vara and the pseudomonas spp gacs-gaca all belong to the same orthologous family of two-component systems as the escherichia coli bara-uvry. in the first four species it has been demonstrated that disruption of this two-component system leads to a clear reduction in virulence of the bacteria. our aim was to determine if the escherichia coli bara-uvry two-component system is connected with virulence usin ... | 2006 | 16529647 |
| cholera stool bacteria repress chemotaxis to increase infectivity. | factors that enhance the transmission of pathogens are poorly understood. we show that vibrio cholerae shed in human 'rice-water' stools have a 10-fold lower oral infectious dose in an animal model than in vitro grown v. cholerae, which may aid in transmission during outbreaks. furthermore, we identify a bacterial factor contributing to this enhanced infectivity: the achievement of a transient motile but chemotaxis-defective state upon shedding from humans. rice-water stool v. cholerae have redu ... | 2006 | 16573690 |
| transcriptional profiling of vibrio cholerae recovered directly from patient specimens during early and late stages of human infection. | understanding gene expression by bacteria during the actual course of human infection may provide important insights into microbial pathogenesis. in this study, we evaluated the transcriptional profile of vibrio cholerae, the causative agent of cholera, in clinical specimens from cholera patients. we collected samples of human stool and vomitus that were positive by dark-field microscopy for abundant vibrios and used a microarray to compare gene expression in organisms recovered directly from sp ... | 2005 | 16040959 |
| psychrophilic superoxide dismutase from pseudoalteromonas haloplanktis: biochemical characterization and identification of a highly reactive cysteine residue. | a psychrophilic superoxide dismutase (sod) has been characterized from the antarctic eubacterium pseudoalteromonas haloplanktis (ph). phsod is a homodimeric iron-containing enzyme and displays a high specific activity, even at low temperature. the enzyme is inhibited by sodium azide and inactivated by hydrogen peroxide; it is also very sensitive to peroxynitrite, a physiological inactivator of the human mitochondrial mn-sod. even though phsod is isolated from a cold-adapted micro-organism, its h ... | 2006 | 16713057 |
| roles of the regulatory proteins flhf and flhg in the vibrio cholerae flagellar transcription hierarchy. | vibrio cholerae, the causative agent of the human diarrheal disease cholera, is a motile bacterium with a single polar flagellum, and motility has been inferred to be an important aspect of virulence. the v. cholerae flagellar hierarchy is organized into four classes of genes. the expression of each class of genes within a flagellar hierarchy is generally tightly regulated in other bacteria by both positive and negative regulatory elements. to further elucidate flagellar biogenesis in v. cholera ... | 2005 | 16159765 |
| detection of free-living and plankton-bound vibrios in coastal waters of the adriatic sea (italy) and study of their pathogenicity-associated properties. | culturable vibrios were isolated from water and plankton fractions collected during an 18-month sampling study performed along the north-central coast of the adriatic sea (italy). unculturable vibrio vulnificus and v. parahaemolyticus were detected in plankton fractions by polymerase chain reaction amplification of dna sequences for cytotoxin-haemolysin and thermolabile haemolysin respectively. the presence of v. parahaemolyticus, v. vulnificus and v. cholerae virulence genes and the expression ... | 2006 | 16817938 |
| postgenomic approaches to cholera vaccine development. | cholera remains an important public health threat. a cholera vaccine that provides durable protection at the mucosal surface, especially among children in endemic settings, is urgently needed. the availability of the complete genome sequence of a clinical isolate of vibrio cholerae o1 el tor has allowed for comparative and functional genomic approaches in the study of cholera. this work holds promise for the identification of bacterial targets of protective human immune responses and may contrib ... | 2006 | 16827618 |
| new drug targets for cholera therapy. | intestinal infection with vibrio cholerae results in secretory diarrhea with potentially massive fluid losses and volume depletion. morbidity and mortality associated with cholera remain a major problem in the developing world despite the success of oral rehydration therapy. new research aiming to inhibit cholera toxin binding to receptors in the intestine provides an attractive strategy for cholera therapy. together with anti-secretory agents, including inhibitors of enkephalinase and of the cy ... | 2005 | 15808339 |
| identification of proinflammatory flagellin proteins in supernatants of vibrio cholerae o1 by proteomics analysis. | the genome of vibrio cholerae contains five flagellin genes that encode proteins (flaa-e) of 39-41 kda with 61-82% identity among them. although the existing live oral attenuated vaccine strains against cholera are protective in humans, there is an intrinsic residual cytotoxic and inflammatory component associated with these candidate vaccine strains. bacterial flagellins are known to be potent inducers of proinflammatory molecules via activation of toll-like receptor 5. here we found that purif ... | 2006 | 16998199 |
| two soluble pyrophosphatases in vibrio cholerae: transient redundancy or enduring cooperation? | soluble pyrophosphatases (ppases), which are essential for cell life, comprise two evolutionarily unrelated families (i and ii). prokaryotic genomes generally contain a single ppase gene encoding either family i or family ii enzyme. surprisingly, four vibrionales species, including the human pathogen vibrio cholerae, contain ppase genes of both families. here we show that both genes are transcriptionally active in v. cholerae, and encode functional ppases when expressed in escherichia coli. in c ... | 2006 | 17009951 |
| human milk oligosaccharides inhibit the adhesion to caco-2 cells of diarrheal pathogens: escherichia coli, vibrio cholerae, and salmonella fyris. | breast-fed children, compared with the bottle-fed ones, have a lower incidence of acute gastroenteritis due to the presence of several antiinfective factors in human milk. the aim of this work is to study the ability of human milk oligosaccharides to prevent infections related to some common pathogenic bacteria. oligosaccharides of human milk were fractionated by gel-filtration and characterized by thin-layer chromatography and high-performance anion exchange chromatography. fractions obtained c ... | 2006 | 16492975 |
| the small nucleoid protein fis is involved in vibrio cholerae quorum sensing. | quorum sensing is a process of cell-cell communication that bacteria use to relay information to one another about the cell density and species composition of the bacterial community. quorum sensing involves the production, secretion and population-wide detection of small signalling molecules called autoinducers. this process allows bacteria to synchronize group behaviours and act as multicellular units. the human pathogen, vibrio cholerae, uses quorum sensing to co-ordinate such complex behavio ... | 2007 | 17181781 |
| nucleotide dependent packing differences in helical crystals of the abc transporter msba. | bacterial atp binding cassette (abc) exporters fulfill a wide variety of transmembrane transport roles and are homologous to the human multidrug resistance p-glycoprotein. recent x-ray structures of the exporters msba and sav1866 have begun to describe the conformational changes that accompany the abc transport cycle. here we present cryo-electron microscopy structures of msba reconstituted into a lipid bilayer. using atpase inhibitors, we captured three nucleotide transition states of the trans ... | 2009 | 19114108 |
| affinity of galectin-8 and its carbohydrate recognition domains for ligands in solution and at the cell surface. | galectin-8 has two different carbohydrate recognition domains (crds), the n-terminal gal-8n and the c-terminal gal-8c linked by a peptide, and has various effects on cell adhesion and signaling. to understand the mechanism for these effects further, we compared the binding activities of galectin-8 in solution with its binding and activation of cells. we used glycan array analysis to broaden the specificity profile of the two galectin-8 crds, as well as intact galectin-8s (short and long linker), ... | 2007 | 17339281 |
| the hlyu protein is a positive regulator of rtxa1, a gene responsible for cytotoxicity and virulence in the human pathogen vibrio vulnificus. | vibrio vulnificus is an opportunistic human pathogen that preferentially infects compromised iron-overloaded patients, causing a fatal primary septicemia with very rapid progress, resulting in a high mortality rate. in this study we determined that the hlyu protein, a virulence factor in v. vulnificus cmcp6, up-regulates the expression of vv20479, a homologue of the vibrio cholerae rtx (repeats in toxin) toxin gene that we named rtxa1. this gene is part of an operon together with two other open ... | 2007 | 17438022 |
| identification of a conserved bacterial protein secretion system in vibrio cholerae using the dictyostelium host model system. | the bacterium vibrio cholerae, like other human pathogens that reside in environmental reservoirs, survives predation by unicellular eukaryotes. strains of the o1 and o139 serogroups cause cholera, whereas non-o1/non-o139 strains cause human infections through poorly defined mechanisms. using dictyostelium discoideum as a model host, we have identified a virulence mechanism in a non-o1/non-o139 v. cholerae strain that involves extracellular translocation of proteins that lack n-terminal hydropho ... | 2006 | 16432199 |
| association of vibrio cholerae o1 el tor and o139 bengal with the copepods acartia tonsa and eurytemora affinis. | the association of vibrio cholerae with zooplankton has been suggested as an important factor in transmission of human epidemic cholera, and the ability to colonize zooplankton surfaces may play a role in the temporal variation and predominance of the two different serogroups (v. cholerae o1 el tor and o139) in the aquatic environment. to date, interactions between specific serogroups and species of plankton remain poorly understood. laboratory microcosm experiments were carried out to compare q ... | 2007 | 17951440 |
| immunologic responses to vibrio cholerae in patients co-infected with intestinal parasites in bangladesh. | infection with intestinal helminths is common and may contribute to the decreased efficacy of vibrio cholerae vaccines in endemic compared to non-endemic areas. however, the immunomodulatory effects of concomitant intestinal parasitic infection in cholera patients have not been systematically evaluated. | 2009 | 19333369 |
| vaccines against traveler's diarrhoea and rotavirus disease - a review. | diarrheal diseases constitute one of the most important health problems worldwide, preferentially in developing countries with a morbidity of estimated 5 billion and a mortality of 5 million cases per year. children less than 5 years are particularly in danger with respect to the incidence and severity of the gastrointestinal symptoms. travelers to developing countries are also at risk to develop diarrheal disorders; around 30-50% of them acquire so called "travelers's diarrhea" caused by bacter ... | 2006 | 17131234 |
| genes induced late in infection increase fitness of vibrio cholerae after release into the environment. | the facultative pathogen vibrio cholerae can exist in both the human small bowel and in aquatic environments. while investigation of the infection process has revealed many factors important for pathogenesis, little is known regarding transmission of this or other water-borne pathogens. using a temporally controlled reporter of transcription, we focus on bacterial gene expression during the late stage of infection and identify a unique class of v. cholerae genes specific to this stage. mutationa ... | 2007 | 18005744 |
| intravenous immunoglobulin contains a broad repertoire of anticarbohydrate antibodies that is not restricted to the igg2 subclass. | specificities for carbohydrate igg antibodies, thought to be predominantly of the igg2 subclass, have never been broadly examined in healthy human subjects. | 2009 | 19443021 |
| detection and identification of enterohemorrhagic escherichia coli o157:h7 and vibrio cholerae o139 using oligonucleotide microarray. | the rapid and accurate detection and identification of the new subtype of the pathogens is crucial for diagnosis, treatment and control of the contagious disease outbreak. here, in this study, an approach to detect and identify escherichia coli o157:h7 and vibrio cholerae o139 was established using oligonucleotide microarray. we coupled multiplex pcr with oligonucleotide microarray to construct an assay suitable for simultaneous identification of two subtypes of the pathogens. | 2007 | 18154687 |
| post-transcriptional cross-talk between pro- and anti-colonization pili biosynthesis systems in vibrio cholerae. | the pathogen vibrio cholerae modulates the expression of many genes in order to transition from its environmental reservoir to its niche in the human host. among these are genes encoding two related type iv pili, the mannose-sensitive haemagglutinin (msha) pilus, which aids v. cholerae persistence in aquatic environments but causes clearance of bacteria by host immune defences, and the toxin co-regulated pilus (tcp) required for colonization. these antagonistic effects are resolved transcription ... | 2008 | 18179420 |
| vibrio vulnificus rtxe is important for virulence, and its expression is induced by exposure to host cells. | numerous secreted virulence factors have been proposed to account for the fulminating and destructive nature of vibrio vulnificus infections. a mutant of v. vulnificus that exhibited less cytotoxicity to int-407 human intestinal epithelial cells was screened from a library of mutants constructed by random transposon mutagenesis. a transposon-tagging method was used to identify and clone an open reading frame encoding an rtx toxin secretion atp binding protein, rtxe, from v. vulnificus. the deduc ... | 2008 | 18250174 |
| effects of salt on the kinetics and thermodynamic stability of endonuclease i from vibrio salmonicida and vibrio cholerae. | adaptation to extreme environments affects the stability and catalytic efficiency of enzymes, often endowing them with great industrial potential. we compared the environmental adaptation of the secreted endonuclease i from the cold-adapted marine fish pathogen vibrio salmonicida (vsenda) and the human pathogen vibrio cholerae (vcenda). kinetic analysis showed that vsenda displayed unique halotolerance. it retained a considerable amount of activity from low concentrations to at least 0.6 m nacl, ... | 2008 | 18312415 |
| vibrio cholerae and aeromonas: do they share a mutual host? | species of the genus aeromonas are native inhabitants of aquatic environments and have recently been considered as an emergent human pathogen. it is estimated that aeromonads cause up to 13% of reported gastroenteritis cases in the united states. although the autochthonous existence of aeromonas in the aquatic environment has been established, its natural reservoir is as yet unknown. chironomids are closely related to mosquitoes except they do not bite and they are the most widely distributed in ... | 2008 | 18317460 |
| relationships between bacteroides 16s rrna genetic markers and presence of bacterial enteric pathogens and conventional fecal indicators. | occurrence and prevalence of different bacterial enteric pathogens as well as their relationships with conventional (total and fecal coliforms) and alternative fecal indicators (host-specific bacteroides 16s rrna genetic markers) were investigated for various water samples taken from different sites with different degrees of fecal contamination. the results showed that a wide range of bacterial pathogens could be detected in both municipal wastewater treatment plant samples and in surface water ... | 2007 | 17507075 |
| rapid screening of toxigenic vibrio cholerae o1 strains from south iran by pcr-elisa. | the ability to sensitively detect vibrio cholera with pcr-elisa method represents a considerable advancement over alternative more time-consuming methods for detection of this pathogen. the aim of this research is to evaluate the suitability of a pcr-enzyme-linked immunosorbent assay for sensitive and rapid detection of v. cholera o1. | 2008 | 18392091 |
| vibrio cholerae infection of drosophila melanogaster mimics the human disease cholera. | cholera, the pandemic diarrheal disease caused by the gram-negative bacterium vibrio cholerae, continues to be a major public health challenge in the developing world. cholera toxin, which is responsible for the voluminous stools of cholera, causes constitutive activation of adenylyl cyclase, resulting in the export of ions into the intestinal lumen. environmental studies have demonstrated a close association between v. cholerae and many species of arthropods including insects. here we report th ... | 2005 | 16201020 |
| representing health, disorder and their transitions by digraphs. | in this study clinical decision making (cdm) is formalized by representing the aetiology and the human body by one directed graph (digraph) and using standard digraph operators (change, add, delete, contract) to model transitions between health and disorder. all nodes of the digraph have the same composite structure <localization, carrier, agent>. for example, an aetiology node is <ganges river, water, vibrio cholera>. paths in the aetiology subdigraph model epidemiological spread. virulent path ... | 2008 | 18487720 |
| vibrio cholerae rnd family efflux systems are required for antimicrobial resistance, optimal virulence factor production, and colonization of the infant mouse small intestine. | vibrio cholerae is a gram-negative human intestinal pathogen that causes the diarrheal disease cholera. humans acquire cholera by ingesting v. cholerae-contaminated food or water. upon ingestion, v. cholerae encounters several barriers to colonization, including bile acid toxicity and antimicrobial products of the innate immune system. in many gram-negative bacteria, resistance to the antimicrobial effects of these products is mediated by rnd (resistance-nodulation-division) family efflux system ... | 2008 | 18490456 |
| identification of a new rtx-like gene cluster in vibrio cholerae. | a gene cluster containing two genes in tandem has been identified in vibrio cholerae eltor n16961. each has more than one cadherin domain and is homologous to the rtx toxin family and was common in various v. cholerae strains. insertional mutagenesis demonstrated that each gene has a role in hep-2 cell rounding, hemolytic activity towards human and sheep rbcs and biofilm formation. the mutants showed reduced adherence to intestinal epithelial cells as well as reduction of in vivo colonization in ... | 2008 | 18510562 |
| pro-autophagic signal induction by bacterial pore-forming toxins. | pore-forming toxins (pft) comprise a large, structurally heterogeneous group of bacterial protein toxins. nucleated target cells mount complex responses which allow them to survive moderate membrane damage by pft. autophagy has recently been implicated in responses to various pft, but how this process is triggered is not known, and the significance of the phenomenon is not understood. here, we show that s. aureus α-toxin, vibrio cholerae cytolysin, streptolysin o and e. coli haemolysin activate ... | 2010 | 20454906 |
| abundance of sewage-pollution indicator and human pathogenic bacteria in a tropical estuarine complex. | studies on abundance and types of various pollution indicator bacterial populations from tropical estuaries are rare. this study was aimed to estimate current levels of pollution indicator as well as many groups of human pathogenic bacteria and their seasonal variations in different locations in mandovi and zuari rivers in the central west coast of india. the sampling covered the estuarine and upstream regions of these rivers representing premonsoon (may 2005), monsoon (september 2006) and post- ... | 2009 | 18633722 |
| characterization of the mrgrs locus of the opportunistic pathogen burkholderia pseudomallei: temperature regulates the expression of a two-component signal transduction system. | burkholderia pseudomallei is a saprophyte in tropical environments and an opportunistic human pathogen. this versatility requires a sensing mechanism that allows the bacterium to respond rapidly to altered environmental conditions. we characterized a two-component signal transduction locus from b. pseudomallei 204, mrgr and mrgs, encoding products with extensive homology with response regulators and histidine protein kinases of escherichia coli, bordetella pertussis, and vibrio cholerae. | 2006 | 16893462 |
| salmonella spp., vibrio spp., clostridium perfringens, and plesiomonas shigelloides in marine and freshwater invertebrates from coastal california ecosystems. | the coastal ecosystems of california are highly utilized by humans and animals, but the ecology of fecal bacteria at the land-sea interface is not well understood. this study evaluated the distribution of potentially pathogenic bacteria in invertebrates from linked marine, estuarine, and freshwater ecosystems in central california. a variety of filter-feeding clams, mussels, worms, and crab tissues were selectively cultured for salmonella spp., campylobacter spp., escherichia coli-o157, clostrid ... | 2006 | 16897302 |
| macrophage migration inhibitory factor plays a role in the regulation of microfold (m) cell-mediated transport in the gut. | it has been shown previously that certain bacteria rapidly (3 h) up-regulated in vivo microfold cell (m cell)-mediated transport of ag across the follicle-associated epithelium of intestinal peyer's patch. our aim was to determine whether soluble mediators secreted following host-bacteria interaction were involved in this event. a combination of proteomics and immunohistochemical analyses was used to identify molecules produced in the gut in response to bacterial challenge in vivo; their effects ... | 2008 | 18832726 |
| importation of the major pilin tcpa gene and frequent recombination drive the divergence of the vibrio pathogenicity island in vibrio cholerae. | the vibrio pathogenicity island (vpi) encodes the toxin-coregulated pilus and other virulence factors for vibrio cholerae to colonize the human intestine to cause cholera. we assessed the level of genetic variation of vpi in nine nonpandemic isolates, and compared them with the sixth and seventh pandemic strains by sequencing c. 5 kb each from the start, middle and end regions of the vpi. variation is similar among the three regions at around 2%, except for the tcpa gene, which has a much higher ... | 2008 | 19054108 |
| [quarantine infectious diseases and sanitary control of territories in modern conditions]. | | 2008 | 18376467 |
| influence of domain architecture and codon usage pattern on the evolution of virulence factors of vibrio cholerae. | cholera remains a heavy burden to human health in some developing countries including india where sanitation is poor and health care is limited. after the publication of the complete genome sequence of vibrio cholerae, the etiological agent of cholera, extensive possibilities, earlier unavailable, have opened up to understand the genetic organization of v. cholerae. in the present study, we analyzed all the pathogenic non-horizontally transferred genes of v. cholerae to know the ancestral relati ... | 2009 | 19159613 |
| an alternative polyamine biosynthetic pathway is widespread in bacteria and essential for biofilm formation in vibrio cholerae. | polyamines are small organic cations found in all cells, and the biosynthetic pathway is well described in eukaryotes and escherichia coli. the characterized pathway uses decarboxylated s-adenosylmethionine as the aminopropyl group donor to form spermidine from putrescine by the key enzymes s-adenosylmethionine decarboxylase and spermidine synthase. we report here the in vivo characterization of an alternative polyamine biosynthetic pathway from vibrio cholerae, the causative agent of human chol ... | 2009 | 19196710 |
| vibrio cholerae cytolysin causes an inflammatory response in human intestinal epithelial cells that is modulated by the prtv protease. | vibrio cholerae is the causal intestinal pathogen of the diarrheal disease cholera. it secretes the protease prtv, which protects the bacterium from invertebrate predators but reduces the ability of vibrio-secreted factor(s) to induce interleukin-8 (il-8) production by human intestinal epithelial cells. the aim was to identify the secreted component(s) of v. cholerae that induces an epithelial inflammatory response and to define whether it is a substrate for prtv. | 2009 | 19907657 |
| unusual case of necrotizing fasciitis caused by vibrio cholerae o137. | we report a case of necrotizing fasciitis caused by vibrio cholerae o137 in an immunocompromised 49-year-old man. the infection was acquired following a minor traumatic injury and exposure to seawater during the summer of 2009 in italy. although highly immunocompromised, the patient survived. the strain was cytotoxic, invasive, and adhesive and contained a fragment of the el tor-like hemolysin (el tor hlya) gene. | 2010 | 21159937 |
| the major vibrio cholerae autoinducer and its role in virulence factor production. | vibrio cholerae, the causative agent of the human disease cholera, uses cell-to-cell communication to control pathogenicity and biofilm formation. this process, known as quorum sensing, relies on the secretion and detection of signalling molecules called autoinducers. at low cell density v. cholerae activates the expression of virulence factors and forms biofilms. at high cell density the accumulation of two quorum-sensing autoinducers represses these traits. these two autoinducers, cholerae aut ... | 2007 | 18004304 |
| prevalence and virulence properties of non-o1 non-o139 vibrio cholerae strains from seafood and clinical samples collected in italy. | seafood and clinical samples collected in italy during 2006 were analyzed to evaluate prevalence, serological and virulence properties of non-o1 non-o139 vibrio cholerae (ncv) isolates. biochemical and serological characterization of the strains was performed by standardized procedures while virulence properties of ncvs were assayed by molecular, in vivo and in vitro toxicological methods. of the 300 seafood samples examined, including mussel, cod, mackerel, anchovy, clam, prawn and cuttlefish, ... | 2009 | 19386376 |
| identification and characterization of a novel type iii secretion system in trh-positive vibrio parahaemolyticus strain th3996 reveal genetic lineage and diversity of pathogenic machinery beyond the species level. | vibrio parahaemolyticus is a bacterial pathogen causative of food-borne gastroenteritis. whole-genome sequencing of v. parahaemolyticus strain rimd2210633, which exhibits kanagawa phenomenon (kp), revealed the presence of two sets of the genes for the type iii secretion system (t3ss) on chromosomes 1 and 2, t3ss1 and t3ss2, respectively. although t3ss2 of the rimd2210633 strain is thought to be involved in human pathogenicity, i.e., enterotoxicity, the genes for t3ss2 have not been found in trh- ... | 2009 | 19075025 |
| insights into the evolution of sialic acid catabolism among bacteria. | sialic acids comprise a family of nine-carbon amino sugars that are prevalent in mucus rich environments. sialic acids from the human host are used by a number of pathogens as an energy source. here we explore the evolution of the genes involved in the catabolism of sialic acid. | 2009 | 19470179 |
| detection of virulence-associated and regulatory protein genes in association with phage typing of human vibrio cholerae from several geographical regions of the world. | vibrio cholerae o1, o139 and occasionally non-o1/non-o139 serogroups are most often responsible for epidemic and pandemic cholera. this study used genotypic patterns of pcr-based detection of virulence-associated and regulatory protein genes, along with phage typing, to characterize 86 v. cholerae strains. thirty-eight of 53 o1 biotype el tor strains harboured both tcpa classical and tcpa el tor genes, and three el tor strains lacked the v. cholerae o1-specific gene (vc-o1); three o139 strains c ... | 2009 | 19528176 |
| benthic ecology of vibrio spp. and pathogenic vibrio species in a coastal mediterranean environment (la spezia gulf, italy). | we carried out a 16-month in situ study to investigate the ecology of vibrio spp. and pathogenic vibrio species in coastal sediments of the mediterranean sea, employing multiple-regression analysis to reveal the major environmental factors controlling their occurrence in the benthic environment. in addition, association between vibrios and sediment-inhabiting meiofauna, which is a major component of benthic ecosystems, was investigated. culturable and total vibrio spp. estimates by most-probable ... | 2009 | 19543938 |
| experimental discovery of srnas in vibrio cholerae by direct cloning, 5s/trna depletion and parallel sequencing. | direct cloning and parallel sequencing, an extremely powerful method for microrna (mirna) discovery, has not yet been applied to bacterial transcriptomes. here we present srna-seq, an unbiased method that allows for interrogation of the entire small, non-coding rna (srna) repertoire in any prokaryotic or eukaryotic organism. this method includes a novel treatment that depletes total rna fractions of highly abundant trnas and small subunit rrna, thereby enriching the starting pool for srna transc ... | 2009 | 19223322 |
| 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 ... | 2010 | 19720009 |
| influence of environmental factors on the presence of vibrio cholerae in the marine environment: a climate link. | evidence indicates that the atmospheric and oceanic processes that occur in response to increased greenhouse gases in the broad-scale climate system may already be changing the ecology of infectious diseases. recent studies have shown that climate also influences the abundance and ecology of pathogens, and the links between pathogens and changing ocean conditions, including human diseases such as cholera. vibrio cholerae is well recognized as being responsible for significant mortality and econo ... | 2007 | 19734600 |
| a novel regulatory protein involved in motility of vibrio cholerae. | the facultative pathogen vibrio cholerae is the causative agent of the human intestinal disease cholera. both motility and chemotaxis of v. cholerae have been shown to contribute to the virulence and spread of cholera. the flagellar gene operons are organized into a hierarchy composed of four classes (i to iv) based on their temporal expression patterns. some regulatory elements involved in flagellar gene expression have been elucidated, but regulation is complex and flagellar biogenesis in v. c ... | 2009 | 19767434 |
| 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 ... | 2010 | 19929967 |
| [laboratory diagnosis of cholera: analysis and prospects for improvement]. | microbiological monitoring of the circulation of vibro cholerae remains one of the key factors contributing to optimization of epidemiological surveillance in a specific area and the laboratory diagnosis of cholera is a basic applied tool for the detection and characterization of isolated cultures. the quality of etiological identification of the pathogen, the competent use of procedures, and the observance of a laboratory diagnosis scheme increases the likelihood of the cholera pathogen being d ... | 2009 | 20030273 |
| familial aggregation of vibrio cholerae-associated infection in matlab, bangladesh. | vibrio cholerae is a major cause of diarrhoeal illness in endemic regions, such as bangladesh. understanding the factors that determine an individual's susceptibility to infection due to v. cholerae may lead to improved prevention and control strategies. increasing evidence suggests that human genetic factors affect the severity of v. cholerae-associated infection. this study, therefore, sought to characterize the heritable component of susceptibility to infection due to v. cholerae using the ma ... | 2009 | 20099756 |
| engineered bacterial communication prevents vibrio cholerae virulence in an infant mouse model. | to investigate the possibility of using commensal bacteria as signal mediators for inhibiting the disease cholera, we stably transformed escherichia coli nissle 1917 (nissle) to express the autoinducer molecule cholera autoinducer 1 (cai-1) (shown previously to prevent virulence when present with another signaling molecule, autoinducer 2, at high concentrations) and determined the effect on vibrio cholerae virulence gene expression and colonization in an infant mouse model. we found that pretrea ... | 2010 | 20534565 |
| hlyu acts as an h-ns antirepressor in the regulation of the rtx toxin gene essential for the virulence of the human pathogen vibrio vulnificus cmcp6. | in vibrio vulnificus, hlyu upregulates the expression of the large rtx toxin gene. in this work we identified the binding site of hlyu to -417 to -376 bp of the rtxa1 operon transcription start site. lacz fusions for a series of progressive deletions from the rtxa1 operon promoter showed that transcriptional activity increased independently of hlyu when its binding site was absent. thus hlyu must regulate the rtxa1 operon expression by antagonizing a negative regulator. concomitantly we found th ... | 2009 | 19320834 |
| 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 ... | 2010 | 19650770 |
| lactic acid as a potential decontaminant of selected foodborne pathogenic bacteria in shrimp (penaeus merguiensis de man). | fresh raw shrimps were dipped for 10, 20, and 30 min at room temperature (25°c ± 1°c) in lactic acid (la; 1.5%, 3.0%, v/v) to evaluate their antipathogenic effects against vibrio cholerae, vibrio parahaemolyticus, salmonella entreitidis, and escherichia coli o157:h7 inoculated at a level of 10(5) cfu/g. significant reductions in the population of all these pathogenic bacteria were recorded after dipping treatments, which were correlated to the corresponding la concentrations and treatment time. ... | 2010 | 21034165 |
| interaction of vibrio cholerae non-o1/non-o139 with copepods, cladocerans and competing bacteria in the large alkaline lake neusiedler see, austria. | vibrio cholerae is a human pathogen and natural inhabitant of aquatic environments. serogroups o1/o139 have been associated with epidemic cholera, while non-o1/non-o139 serogroups usually cause human disease other than classical cholera. v. cholerae non-o1/non-o139 from the neusiedler see, a large central european lake, have caused ear and wound infections, including one case of fatal septicaemia. recent investigations demonstrated rapid planktonic growth of v. cholerae non-o1/non-o139 and corre ... | 2010 | 21049271 |
| conventional and molecular methods to detect bacterial pathogens in mussels. | to detect aeromonas spp., salmonella spp., vibrio cholerae, vibrio parahaemolyticus and vibrio vulnificus in mussels and water samples from a farming area, conventional and molecular methods were applied to enrichment cultures. | 2010 | 21070267 |
| phenotypic and genotypic characterization vibrio cholerae o139 of clinical and aquatic isolates in china. | to enhance the understanding of epidemiological impact of environmental vibrio cholerae o139 strains, we characterized 10 clinical and 20 environmental isolates collected from human clinical samples and pear river estuary during 2006 to 2008. isolates were tested by pcr for eight virulence genes: cholera toxin (ctxa), zonula occludens toxin (zot), accessory cholera enterotoxin (ace), hemolysin (hlya), nag-specific heat-stable toxin (st), toxin-coregulated pilus (tcpa), outer membrane protein (om ... | 2010 | 21079963 |
| quorum sensing and a global regulator tsra control expression of type vi secretion and virulence in vibrio cholerae. | vibrio cholerae is a human pathogen that causes the life-threatening diarrheal disease cholera. a type vi secretion system (t6ss) was recently shown to be required for full virulence in the o37 serogroup strain v52, which causes only sporadic human disease, but t6ss is not expressed in seventh pandemic o1 el tor strains under standard laboratory conditions. in this study, we show that in the o1 el tor strain c6706, t6ss is repressed by both quorum sensing and the uncharacterized protein vc0070 ( ... | 2010 | 21084635 |
| evidence-based point-of-care tests and device designs for disaster preparedness. | to define pathogen tests and device specifications needed for emerging point-of-care (poc) technologies used in disasters. | 2010 | 21162410 |
| 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 ... | 2010 | 21187377 |
| bacterial diseases of crabs: a review. | bacterial diseases of crabs are manifested as bacteremias caused by organisms such as vibrio, aeromonas, and a rhodobacteriales-like organism or tissue and organ tropic organisms such as chitinoclastic bacteria, rickettsia intracellular organisms, chlamydia-like organism, and spiroplasma. this paper provides general information about bacterial diseases of both marine and freshwater crabs. some bacteria pathogens such as vibrio cholerae and vibrio vulnificus occur commonly in blue crab haemolymph ... | 2011 | 21215353 |
| aqueous synthesis of znte/dendrimer nanocomposites and their antimicrobial activity: implications in therapeutics. | the present strategy proposes a simple and single step aqueous route for synthesizing stable, fluorescent znte/dendrimer nanocomposites with varying dendrimer terminal groups. in these hybrid materials, the fluorescence of the semiconductor combines with the biomimetic properties of the dendrimer making them suitable for various biomedical applications. the znte nanocomposites thus obtained demonstrate bactericidal activity against enteropathogenic bacteria without having toxic effects on the hu ... | 2011 | 21218228 |
| use of ompu porins for attachment and invasion of crassostrea gigas immune cells by the oyster pathogen vibrio splendidus. | ompu porins are increasingly recognized as key determinants of pathogenic host vibrio interactions. although mechanisms remain incompletely understood, various species, including the human pathogen vibrio cholera, require ompu for host colonization and virulence. we have shown previously that ompu is essential for virulence in the oyster pathogen vibrio splendidus lgp32. here, we showed that v. splendidus lgp32 invades the oyster immune cells, the hemocytes, through subversion of host-cell actin ... | 2011 | 21282662 |
| structural and unfolding features of hlyt, a tetrameric lysr type transcription regulator of vibrio cholerae. | hlyt from vibrio cholerae is a positive regulator of na(+)/h(+) antiporter, important for the survival of the organism in an aquatic environment and within the human host. here we report cloning, over-expression and purification of hlyt. analytical gel filtration and glutaraldehyde cross-linking indicate existence of tetrameric and dimeric forms of hlyt in solution. we propose an unfolding model of hlyt on the basis of guanidine hydrochloride-induced equilibrium unfolding, analyzed by cd and spe ... | 2009 | 19427417 |
| lessons from cholera & vibrio cholerae. | cholera is an acute form of diarrhoeal disease that plagued human civilization over the centuries. the sudden and explosive onset of the disease in the form of an outbreak or epidemic, coupled with high mortality and morbidity rates, had a tragic impact on the personal as well as social life of people living in the affected areas. the enormity of human sufferings led clinicians and scientists to carry out extensive research on cholera and vibrio cholerae (the causative bacterium of the disease) ... | 2011 | 21415490 |
| monitoring of multiple drug-resistant pathogens in a selected stretch of bay of bengal, india. | the present work aims at identification of multiple drug-resistant pathogenic bacteria in a selected stretch, namely, puri on the bay of bengal, india. six stations at the coast of puri were selected and samples of water and sediment were collected during the winter of 2008 and 2009 for this study. thirty-eight pathogenic bacteria were isolated and identified from both the water and the sediment of 6 fixed stations (pu-1a, pu-1b, pu-2, pu-3, pu-4, and pu-5). the identified pathogens were escheri ... | 2011 | 21424669 |
| proteases produced by vibrios. | bacteria of the genus vibrio are normal habitants of the aquatic environment but the some species are believed to be human pathogens. pathogenic vibrios produce various pathogenic factors, and the proteases are also recognized to play pathogenic roles in the infection: the direct roles by digesting many kinds of host proteins or indirect roles by processing other pathogenic protein factors. especially vvp from vibrio vulnificus is thought to be a major pathogenic factor of the vibrio. although h ... | 2011 | 21467624 |
| evaluation of a new chromogenic medium, chromid™ vibrio, for the isolation and presumptive identification of vibrio cholerae and vibrio parahaemolyticus from human clinical specimens. | the aim of this study was to evaluate the performance of the chromid™ vibrio medium for the detection of vibrio cholerae and v. parahaemolyticus in stool and swab specimens in comparison with thiosulfate citrate bile salts sucrose (tcbs) medium. a total of 96 samples including 30 fresh stool, 32 stool, and 34 swab specimens originating from routine laboratories were tested. all samples were seeded on both media, the tcbs medium and the chromid vibrio, directly and after an enrichment step on alk ... | 2011 | 21484255 |
| suppressed induction of proinflammatory cytokines by a unique metabolite produced by vibrio cholerae o1 el tor biotype in cultured host cells. | vibrio cholerae o1 has two biotypes, el tor and classical, and the latter is now presumed to be extinct in nature. in carbohydrate-rich growth conditions, el tor biotype strains produce the neutral fermentation end product 2,3-butanediol (2,3-bd), which prevents accumulation of organic acids from mixed acid fermentation and thus avoids a lethal decrease in the medium ph, while the classical biotype strains fail to do the same. in this study, we investigated the inhibitory effect of 2,3-bd on the ... | 2011 | 21576340 |
| the rocks and shallows of deep rna sequencing: examples in the vibrio cholerae rnome. | new deep rna sequencing methodologies in transcriptome analyses identified a wealth of novel nonprotein-coding rnas (npcrnas). recently, deep sequencing was used to delineate the small npcrna transcriptome of the human pathogen vibrio cholerae and 627 novel npcrna candidates were identified. here, we report the detection of 223 npcrna candidates in v. cholerae by different cdna library construction and conventional sequencing methods. remarkably, only 39 of the candidates were common to both sur ... | 2011 | 21610211 |
| n-terminal residues of the vibrio cholerae virulence regulatory protein toxt involved in dimerization and modulation by fatty acids. | the regulatory protein toxt is an arac family protein that is responsible for activating transcription of the genes encoding cholera toxin and toxin coregulated pilus, which are required for virulence by the human pathogen vibrio cholerae. the n terminus of toxt contains dimerization and regulatory elements, whereas the c terminus contains the dna binding domain. bile and long chain fatty acids negatively regulate toxt activity. utilizing a comprehensive alanine substitution mutant library of to ... | 2011 | 21673111 |
| contamination of community water sources by potentially pathogenic vibrios following sea water inundation. | potentially pathogenic members of the vibrionaceae family including vibrio cholerae and vibrio parahemolyticus were isolated from domestic sources of drinking water in coastal villages following sea water inundation during the tsunami in southern india. phenotypic and genotypic studies were done to confirm the identity and detection of toxins. vibrio-gyr (gyrase b gene) was detected in all sixteen vibrio isolates. toxin regulating genes i.e.: ctx gene, tdh gene, and trh gene, however were not de ... | 2007 | 18697592 |
| 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 ... | 2010 | 20816895 |
| 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 ... | 2010 | 20824430 |
| 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 ... | 2010 | 20855558 |