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networking in microbes: conjugative elements and plasmids in the genus alteromonas.to develop evolutionary models for the free living bacterium alteromonas the genome sequences of isolates of the genus have been extensively analyzed. however, the main genetic exchange drivers in these microbes, conjugative elements (ces), have not been considered in detail thus far. in this work, ces have been searched in several complete alteromonas genomes and their sequence studied to understand their role in the evolution of this genus. six genomes are reported here for the first time.201728056800
the expanding role of type ii secretion in bacterial pathogenesis and beyond.type ii secretion (t2s) is one means by which gram-negative pathogens secrete proteins into the extracellular milieu and/or host organisms. based upon recent genome sequencing, it is clear that t2s is largely restricted to the proteobacteria, occurring in many, but not all genera in the α-, β-, γ-, and δ- classes. prominent human and/or animal pathogens that express a t2s system(s) include acinetobacter baumannii, burkholderia pseudomallei, chlamydia trachomatis, escherichia coli, klebsiella pne ...201728264910
pathogenic mechanisms of actin cross-linking toxins: peeling away the layers.actin cross-linking toxins are produced by gram-negative bacteria from vibrio and aeromonas genera. the toxins were named actin cross-linking domains (acd), since the first and most of the subsequently discovered acds were found as effector domains in larger martx and vgrg toxins. among recognized human pathogens, acd is produced by vibrio cholerae, vibrio vulnificus, and aeromonas hydrophila. upon delivery to the cytoplasm of a host cell, acd covalently cross-links actin monomers into non-polym ...201727858184
a comparative study of cold- and warm-adapted endonucleases a using sequence analyses and molecular dynamics simulations.the psychrophilic and mesophilic endonucleases a (enda) from aliivibrio salmonicida (vsenda) and vibrio cholera (vcenda) have been studied experimentally in terms of the biophysical properties related to thermal adaptation. the analyses of their static x-ray structures was no sufficient to rationalize the determinants of their adaptive traits at the molecular level. thus, we used molecular dynamics (md) simulations to compare the two proteins and unveil their structural and dynamical differences ...201728192428
raw ready-to-eat seafood safety: microbiological quality of the various seafood species available in fishery, hyper and online markets.microbiological quality of 206 raw ready-to-eat seafood samples was investigated according to species (gizzard shad, halibut, rockfish, tuna, oyster and squid) and distribution channels (fishery, hyper and online market). enumeration of aerobic plate count and total coliforms (tc) and pathogenic bacteria (bacillus cereus, staphylococcus aureus and vibrio parahaemolyticus) was performed, and level of microbiological quality was classified into four groups: satisfactory, acceptable, unsatisfactory ...201727747902
antimicrobial effects of novel peptides cot2 and sot2 derived from crocodylus siamensis and pelodiscus sinensis ovotransferrins.in light of the increasing threat of bacterial drug resistance to human health on a global scale, research and development of antimicrobial peptides as a novel class of potent antibiotics has gained considerable attention. the present study focuses on the structural evaluation and membrane interaction of two new cationic antimicrobial peptides, cot2 and sot2, derived from siamese crocodile (crocodylus siamensis) and chinese softshell turtle (pelodiscus sinensis) ovotransferrins. here, cot1 (+3) ...201728159460
interferon-inducible guanylate-binding proteins at the interface of cell-autonomous immunity and inflammasome activation.guanylate-binding proteins (gbps) are essential components of cell-autonomous immunity. in response to ifn signaling, gbps are expressed in the cytoplasm of immune and nonimmune cells, where they unleash their antimicrobial activity toward intracellular bacteria, viruses, and parasites. recent studies have revealed that gbps are essential for mediating activation of the caspase-1 inflammasome in response to the gram-negative bacteria salmonella enterica serovar typhimurium, francisella novicida, ...201727418355
targeting and alteration of tight junctions by bacteria and their virulence factors such as clostridium perfringens enterotoxin.the integrity of tight junctions, which regulate paracellular permeability, is challenged by many bacterial pathogens. this is caused by inflammatory responses triggered by pathogens and direct interaction of bacteria or their toxins with host epithelial cells. in some cases, tight junction proteins represent receptors for cell surface proteins or toxins of the pathogen, such as clostridium perfringens enterotoxin (cpe). cpe causes diarrhea and cramps-the symptoms of a common foodborne illness, ...201727864644
fast growth conditions uncouple the final stages of chromosome segregation and cell division in escherichia coli.homologous recombination between the circular chromosomes of bacteria can generate chromosome dimers. they are resolved by a recombination event at a specific site in the replication terminus of chromosomes, dif, by dedicated tyrosine recombinases. the reaction is under the control of a cell division protein, ftsk, which assembles into active dna pumps at mid-cell during septum formation. previous studies suggested that activation of xer recombination at dif was restricted to chromosome dimers i ...201728358835
ribosome-dependent vibrio cholerae mrnase higb2 is regulated by a β-strand sliding mechanism.toxin-antitoxin (ta) modules are small operons involved in bacterial stress response and persistence. higba operons form a family of ta modules with an inverted gene organization and a toxin belonging to the rele/pare superfamily. here, we present the crystal structures of chromosomally encoded vibrio cholerae antitoxin (vchiga2), toxin (vchigb2) and their complex, which show significant differences in structure and mechanisms of function compared to the higba module from plasmid rts1, the defin ...201728334932
induction of immunomodulatory mir-146a and mir-155 in small intestinal epithelium of vibrio cholerae infected patients at acute stage of cholera.the potential immunomodulatory role of micrornas in small intestine of patients with acute watery diarrhea caused by vibrio cholerae o1 or enterotoxigenic escherichia coli (etec) infection was investigated. duodenal biopsies were obtained from study-participants at the acute (day 2) and convalescent (day 21) stages of disease, and from healthy individuals. levels of mir-146a, mir-155 and mir-375 and target gene (irak1, traf6, card10) and 11 cytokine mrnas were determined by qrt-pcr. the cellular ...201728319200
stringent factor and proteolysis control of sigma factor rpos expression in vibrio cholerae.vibrio cholerae can colonize the gastrointestinal track of humans and cause the disease cholera. during colonization, the alternative sigma factor, rpos, controls a process known as "mucosal escape response," defining a specific spatial and temporal response and effecting chemotaxis and motility. in this report, the expression and proteolytic control of rpos in v. cholerae was characterized. to date, aspects of proteolysis control, the involved components, and proteolysis regulation have not bee ...201728228329
structure and dynamics of type iii periplasmic proteins vcfhud and vchutb reveal molecular basis of their distinctive ligand binding properties.molecular mechanisms of xenosiderophore and heme acquisitions using periplasmic binding protein (pbp) dependent atp-binding cassette transporters to scavenge the essential nutrient iron are elusive yet in vibrio cholerae. our current study delineates the structures, dynamics and ligand binding properties of two type iii pbps of v. cholerae, vcfhud and vchutb. through crystal structures and fluorescence quenching studies we demonstrate unique features of vcfhud to bind both hydroxamate and catech ...201728216648
surface expression of helicobacter pylori hpaa adhesion antigen on vibrio cholerae, enhanced by co-expressed enterotoxigenic escherichia coli fimbrial antigens.helicobacter pylori infection can cause peptic ulceration and is associated with gastric adenocarcinoma. this study aimed to construct and characterize a non-virulent vibrio cholerae o1 strain, which grows more rapidly than h. pylori, as vector for h. pylori antigens for possible use as a vaccine strain against h. pylori. this was done by recombinant expression of the h. pylori adhesion antigen hpaa alone or, as a proof of principle, together with different colonization factor (cf) antigens of e ...201728215587
attachment of 13 types of foodborne bacteria to jalapeño and serrano peppers and antibacterial effect of roselle calyx extracts, sodium hypochlorite, colloidal silver, and acetic acid against these foodborne bacteria on peppers.chili peppers are a very important crop in mexico. however, these peppers have been associated with salmonella infection outbreaks in the united states, and salmonella and diarrheagenic escherichia coli pathotypes have been isolated from jalapeño and serrano peppers in mexico. to decrease microbial contamination of fruits and vegetables, chemical agents are commonly used; however, chemical agents used to eliminate pathogenic bacteria on vegetables have a limited antimicrobial effect. roselle ( h ...201728199144
identification and antimicrobial resistance patterns of bacterial enteropathogens from children aged 0-59 months at the university teaching hospital, lusaka, zambia: a prospective cross sectional study.bacterial diarrhoeal disease is among the most common causes of mortality and morbidity in children 0-59 months at the university teaching hospital in lusaka, zambia. however, most cases are treated empirically without the knowledge of aetiological agents or antimicrobial susceptibility patterns. the aim of this study was, therefore, to identify bacterial causes of diarrhoea and determine their antimicrobial susceptibility patterns in stool specimens obtained from the children at the hospital.201728152988
cross feeding of glucose metabolism byproducts of escherichia coli human gut isolates and probiotic strains affect survival of vibrio cholerae.vibrio cholerae converts glucose into either acid or the neutral end product acetoin and its survival in carbohydrate enriched media is linked to the nature of the byproducts produced. it has been demonstrated in this study that escherichia coli strain isolated from the gut of healthy human volunteers and the commonly used probiotic e. coli nissle strain that metabolize glucose to acidic byproducts drastically reduce the survival of v. cholerae strains irrespective of their glucose sensitivity a ...201728105081
structural insights into the secretin translocation channel in the type ii secretion system.the secretin gspd of the type ii secretion system (t2ss) forms a channel across the outer membrane in gram-negative bacteria to transport substrates from the periplasm to the extracellular milieu. the lack of an atomic-resolution structure of the gspd channel hinders the investigation of substrate translocation mechanism of t2ss. here we report cryo-em structures of two gspd channels (∼1 mda), from escherichia coli k12 and vibrio cholerae, at ∼3 å resolution. the structures reveal a pentadecamer ...201728067918
xer site specific recombination: double and single recombinase systems.the separation and segregation of newly replicated bacterial chromosomes can be constrained by the formation of circular chromosome dimers caused by crossing over during homologous recombination events. in escherichia coli and most bacteria, dimers are resolved to monomers by site-specific recombination, a process performed by two chromosomally encoded tyrosine recombinases (xerc and xerd). xercd recombinases act at a 28 bp recombination site dif, which is located at the replication terminus reg ...201728373867
immunochromatographic detection of the heat-labile enterotoxin of enterotoxigenic escherichia coli with cross-detection of cholera toxin.here, we report the development of an immunochromatographic test strip that can detect heat-labile enterotoxin (lt) produced by enterotoxigenic escherichia coli. five types of monoclonal antibody (mab)-producing hybridomas were isolated: three mabs were a subunit specific and two were b subunit specific. four mabs also cross-reacted with both lt proteins derived from swine and human e. coli strains, but only one mab 57b9 additionally cross-reacted with cholera toxin. thus, mab 57b9 was used to f ...201727940044
random versus cell cycle-regulated replication initiation in bacteria: insights from studying vibrio cholerae chromosome 2.bacterial chromosomes initiate replication at a fixed time in the cell cycle, whereas there is generally no particular time for plasmid replication initiation or chromosomal replication initiation from integrated plasmids. in bacteria with divided genomes, the replication system of one of the chromosomes typically resembles that of bacteria with undivided genomes, whereas the remaining chromosomes have plasmid-like replication systems. for example, in vibrio cholerae, a bacterium with two chromo ...201727903655
ctxϕ: exploring new alternatives in host factor-mediated filamentous phage replications.for a long time ff phages from escherichia coli provided the majority of the knowledge about the rolling circle replication mechanism of filamentous phages. host factors involved in coliphages replication have been fully identified. based on these studies, the function of rep protein as the accessory helicase directly implicated in filamentous phage replication was considered a paradigm. we recently reported that the replication of some filamentous phages from vibrio cholerae, including the chol ...201727607139
in vitro antibacterial activity of aqueous and ethanol extracts of aristolochia indica and toddalia asiatica against multidrug-resistant bacteria.bacteria have developed multidrug resistance against available antimicrobial agents. infectious diseases caused by these multidrug-resistant bacteria are major causes of morbidity and mortality in human beings. synthetic drugs are expensive and inadequate for the treatment of diseases, causing side effects and ineffective against multidrug-resistant bacteria. the medicinal plants are promising to have effective antimicrobial property due to presence of phytochemical compounds like alkaloids, fla ...201726997710
antibacterial and antispasmodic activities of a dichloromethane fraction of an ethanol extract of stem bark of piliostigma reticulatum.this study presents the antispasmodic and antibacterial properties of an ethanol extract and fractions the of stem bark of piliostigma reticulatum.201725883517
mechanisms for pseudoalteromonas piscicida-induced killing of vibrios and other bacterial pathogens.pseudoalteromonas piscicida are gram-negative gammaproteobacteria found in the marine environment. three strains of pigmented p. piscicida were isolated from seawater and partially characterized by inhibition studies, electron microscopy, and proteolytic enzyme production. growth inhibition and death occurred around colonies of p. piscicida on lawns of the naturally-occurring marine pathogens vibrio vulnificus, v. parahaemolyticus, v. cholerae, photobacterium damselae and shewanella algae inhibi ...201728363962
repair of a bacterial small β-barrel toxin pore depends on channel width.membrane repair emerges as an innate defense protecting target cells against bacterial pore-forming toxins. here, we report the first paradigm of ca(2+)-dependent repair following attack by a small β-pore-forming toxin, namely, plasmid-encoded phobalysin of photobacterium damselae subsp. damselae in striking contrast, vibrio cholerae cytolysin, the closest ortholog of phobalysin, subverted repair. mutational analysis uncovered a role of channel width in toxicity and repair. thus, the replacement ...201728196960
vope, a vibrio cholerae type iii effector, attenuates the activation of cwi-mapk pathway in yeast model system.vope, a mitochondrial targeting t3ss effector protein of vibrio cholerae, perturbs innate immunity by modulating mitochondrial dynamics. in the current study, ectopic expression of vope was found to be toxic in a yeast model system and toxicity was further aggravated in the presence of various stressors. interestingly, a vope variant lacking predicted mitochondrial targeting sequence (mts) also exhibited partial lethality in the yeast system. with the aid of yeast genetic tools and different str ...201728373966
iridoids from canthium subcordatum iso-butanol fraction with potent biological activities.the continuous emergence of multi-drug-resistant bacteria drastically reduces the efficacy of antibiotic armory and, consequently, increases the frequency of therapeutic failure. the discovery of new antibacterial drugs is an urgent need. the present study reports the antibacterial and antioxidant activities of the methanol extract, fractions and iridoids from canthium subcordatum, a plant traditionally used as antidiabetic, anti-inflammatory, and antimicrobial.201728056944
complex secondary metabolites from ludwigia leptocarpa with potent antibacterial and antioxidant activities.diarrhea continues to be one of the most common causes of morbidity and mortality among infants and children in developing countries. the aim of the present study was to evaluate the antibacterial and antioxidant activities of extracts and compounds from ludwigia leptocarpa, a plant traditionally used for its vermifugal, anti-dysenteric, and antimicrobial properties. a methanol extract was prepared by maceration of the dried plant and this was successively extracted with ethyl acetate to obtain ...201727431270
biological properties and chemical composition of jatropha neopauciflora pax.ethnopharmacological relevance. jatropha neopauciflora (pax) is an endemic species of the tehuacan- cuicatlan valley, mexico. this species has long been used as a remedy to alleviate illnesses of bacterial, fungal and viral origin. aim of the study. experimentally test the traditional use of jatropha neopauciflora in mexican traditional medicine.201728331913
season-specific occurrence of potentially pathogenic vibrio spp. on the southern coast of south korea.vibrio species are widely distributed in warm estuarine and coastal environments, and they can infect humans through the consumption of raw and mishandled contaminated seafood. in this study, we aimed to isolate and observe the distribution of enteropathogenic vibrio spp. from environments of the southern coast of south korea over a season cycle. a total of 10,983 isolates of vibrio spp. were obtained from tidal water and mud samples over a 1-year period from five sampling sites along the southw ...201727836844
3-amino 1,8-naphthalimide, a structural analog of the anti-cholera drug virstatin inhibits chemically-biased swimming and swarming motility in vibrios.a screen for inhibitors of vibrio cholerae motility identified the compound 3-amino 1,8-naphthalimide (3-a18ni), a structural analog of the cholera drug virstatin. similar to virstatin, 3-a18ni diminished cholera toxin production. in contrast, 3-a18ni impeded swimming and/or swarming motility of v. cholerae and v. parahemolyticus suggesting that it could target the chemotaxis pathway shared by the polar and lateral flagellar system of vibrios. 3-a18ni did not inhibit the expression of v. cholera ...201728392408
chemotactic behaviors of vibrio cholerae cells.vibrio cholerae, the causative agent of cholera, swims in aqueous environments with a single polar flagellum. in a spatial gradient of a chemical, the bacterium can migrate in "favorable" directions, a property that is termed chemotaxis. the chemotaxis of v. cholerae is not only critical for survival in various environments and but also is implicated in pathogenicity. in this chapter, we describe how to characterize the chemotactic behaviors of v. cholerae: these methods include swarm assay, tem ...201728389961
an electrochemical strategy using multifunctional nanoconjugates for efficient simultaneous detection of escherichia coli o157: h7 and vibrio cholerae o1.the rapid and accurate quantification of the pathogenic bacteria is extremely critical to decrease the bacterial infections in all areas related to health and safety. we have developed an electrochemical strategy for simultaneous ultrasensitive detection of e. coli o157:h7 and vibrio cholerae o1. this approach was based on the specific immune recognition of different pathogenic bacteria by multifunctional nanoconjugates and subsequent signal amplification. by employing the proposed biosensor, th ...201728382165
iron chelators inhibit the heme-degradation reaction by hutz from vibrio cholerae.hutz is a heme-degrading enzyme. we found that the heme-degradation reaction by hutz is inhibited by the iron chelators. kinetic analysis of each heme-degradation step suggests that water molecules hydrogen bonded to thr27 are involved in proton transfer to fe(iii)-oo(-), and that this step is inhibited by iron chelators.201728352909
non-o1/non-o139 vibrio cholerae septicaemia in a saudi man: a case report.background. the non-o1/non-o139 serogroups of vibrio cholerae occur in diverse natural niches, and usually cause mild and self-limiting gastrointestinal illness. however, they have well-documented potential to cause invasive and extra-intestinal infections among immunocompromised patients. furthermore, their ability to grow in low-salinity surface water, and the existence of asymptomatic human carriers, suggest novel acquisition routes for this unusual infection, even in people without obvious r ...201728348803
vibrio cholerae vcib mediates iron reduction.vibrio cholerae is the causative agent of the severe diarrheal disease cholera. v. cholerae thrives within the human host where it replicates to high numbers but also persists within the aquatic environments of ocean and brackish water. to survive within these nutritionally diverse environments, v. cholerae must encode the necessary tools to acquire the essential nutrient iron in all forms it may encounter. a prior study of systems involved in iron transport in v. cholerae revealed the existence ...201728348025
environmental fluctuation governs selection for plasticity in biofilm production.bacteria can grow in a free-swimming state, as planktonic cells, or in surface-attached communities, termed biofilms. the planktonic and biofilm growth modes differ dramatically with respect to spatial constraints, nutrient access, population density and cell-cell interactions. fitness trade-offs underlie how successfully bacteria compete in each of these environments. accordingly, some bacteria have evolved to be specialists in biofilm formation, while others specialize in planktonic growth. th ...201728338673
chloroform-free permeabilization for improved detection of β-galactosidase activity in vibrio cholerae.lacz (β-galactosidase) is used to monitor the transcription of genes in reporter strains carrying the lacz gene under the control of a promotor of interest. this protocol for lacz activity determinations in vibrio cholerae following detergent lysis results in 2.5-fold increase of lacz activities compared to lysis with chloroform.201728336461
a new class of inhibitors of the arac family virulence regulator vibrio cholerae toxt.vibrio cholerae is responsible for the diarrheal disease cholera that infects millions of people worldwide. while vaccines protecting against cholera exist, and oral rehydration therapy is an effective treatment method, the disease will remain a global health threat until long-term solutions such as improved sanitation and access to clean water become widely available. because of this, there is a pressing need for potent therapeutics that can either mitigate cholera symptoms, or act prophylactic ...201728332578
sequential displacement of type vi secretion system effector genes leads to evolution of diverse immunity gene arrays in vibrio cholerae.type vi secretion systems (t6ss) enable bacteria to engage neighboring cells in contact-dependent competition. in vibrio cholerae, three chromosomal clusters each encode a pair of effector and immunity genes downstream of those encoding the t6ss structural machinery for effector delivery. different combinations of effector-immunity proteins lead to competition between strains of v. cholerae, which are thought to be protected only from the toxicity of their own effectors. screening of all publica ...201728327641
occurrence and virulence properties of vibrio and salinivibrio isolates from tropical lagoons of the southern caribbean sea.the vibrionaceae are gram-negative bacteria present in marine and estuarine environments worldwide, including several species known as important pathogens to humans and aquatic organisms. the aim of this research was to investigate the occurrence and virulence properties of vibrio and salinivibrio isolated from lagoons at cuare wildlife refuge and margarita island in the southern caribbean sea. water, plankton and oyster samples were collected during october 2011 and march 2012 and examined by s ...201728324231
a vibrio cholerae autoinducer-receptor pair that controls biofilm formation.quorum sensing (qs) is a cell-cell communication process that enables bacteria to track cell population density and orchestrate collective behaviors. qs relies on the production and detection of, and the response to, extracellular signal molecules called autoinducers. in vibrio cholerae, multiple qs circuits control pathogenesis and biofilm formation. here, we identify and characterize a new qs autoinducer-receptor pair. the autoinducer is 3,5-dimethylpyrazin-2-ol (dpo). dpo is made from threoni ...201728319101
synthesis and human/bacterial carbonic anhydrase inhibition with a series of sulfonamides incorporating phthalimido moieties.a series of sulfonamides was obtained by reacting substituted-2-(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxamido)benzoic acids with aromatic sulfonamides incorporating primary amino moieties. the new compounds were investigated as inhibitor of four carbonic anhydrase (ca, ec 4.2.1.1) isoforms, the human (h) hca i and ii, and the α- and β-class cas from the pathogenic bacterium vibrio cholerae, vchcaα and vhccaβ. hca i was effectively inhibited by the new sulfonamides, with inhibition constants ...201728318894
cholera.cholera is an acute, watery diarrhoeal disease caused by vibrio cholerae of the o1 or o139 serogroups. in the past two centuries, cholera has emerged and spread from the ganges delta six times and from indonesia once to cause global pandemics. rational approaches to the case management of cholera with oral and intravenous rehydration therapy have reduced the case fatality of cholera from more than 50% to much less than 1%. despite improvements in water quality, sanitation, and hygiene, as well a ...201728302312
late assembly of the vibrio cholerae cell division machinery postpones septation to the last 10% of the cell cycle.bacterial cell division is a highly regulated process, which involves the formation of a complex apparatus, the divisome, by over a dozen proteins. in the few model bacteria in which the division process was detailed, divisome assembly occurs in two distinct steps: a few proteins, including the ftsz tubulin-like protein, form a membrane associated contractile ring, the z-ring, at ~30% of the cell cycle. the z-ring serves as a scaffold for the recruitment of a second series of proteins, including ...201728300142
identification of the binding sites for ubiquinone and inhibitors in the na(+)-pumping nadh-ubiquinone oxidoreductase of vibrio cholerae by photoaffinity labeling.the na(+)-pumping nadh-quinone oxidoreductase (na(+)-nqr) is the first enzyme of the respiratory chain and the main ion transporter in many marine and pathogenic bacteria, including vibrio cholerae the v. cholerae na(+)-nqr has been extensively studied, but its binding sites for ubiquinone and inhibitors remain controversial. here, using a photoreactive ubiquinone puq-3 as well as two aurachin-type inhibitors [(125)i]pad-1 and [(125)i]pad-2 and photoaffinity labeling experiments on the isolated ...201728298441
fish as hosts of vibrio cholerae.vibrio cholerae, the causative agent of pandemic cholera, is abundant in marine and freshwater environments. copepods and chironomids are natural reservoirs of this species. however, the ways v. cholerae is globally disseminated are as yet unknown. here we review the scientific literature that provides evidence for the possibility that some fish species may be reservoirs and vectors of v. cholerae. so far, v. cholerae has been isolated from 30 fish species (22 freshwater; 9 marine). v. cholerae ...201728293221
an amoebal grazer of cyanobacteria requires cobalamin produced by heterotrophic bacteria.amoebae are unicellular eukaryotes that consume microbial prey through phagocytosis, playing a role in shaping microbial foodwebs. many amoebal species can be cultivated axenically in rich media or monoxenically with single bacterial prey species. here we characterize heterolobosean amoeba lpg3, a recent natural isolate, which is unable to grow on unicellular cyanobacteria, its primary food source, in the absence of a heterotrophic bacterium, a pseudomonas species coisolate. to investigate the m ...201728283521
vibrio cholerae lipopolysaccharide loaded chitosan nanoparticle could save life by induction of specific immunoglobulin isotype.the lipopolysaccharide (lps) of vibrio cholerae (v. cholerae) plays an important role in cholera disease and the induction of primary protection. in this study, we evaluate mice humoral immune response in intranasal and intraperitoneal administrated v. cholerae lps. the results showed that the intranasal administration of lps-chitosan nanoparticle induced the high level of antibodies compared to intraperitoneal injection of antigen without chitosan (p < .001). these results indicated that intran ...201728278575
vibrio cholerae o1 with reduced susceptibility to ciprofloxacin and azithromycin isolated from a rural coastal area of bangladesh.cholera outbreaks occur each year in the remote coastal areas of bangladesh and epidemiological surveillance and routine monitoring of cholera in these areas is challenging. in this study, a total of 97 vibrio cholerae o1 isolates from mathbaria, bangladesh, collected during 2010 and 2014 were analyzed for phenotypic and genotypic traits, including antimicrobial susceptibility. of the 97 isolates, 95 possessed ctx-phage mediated genes, ctxa, ace, and zot, and two lacked the cholera toxin gene, c ...201728270803
pandemics, pathogenicity and changing molecular epidemiology of cholera in the era of global warming.vibrio cholerae, a gram-negative, non-spore forming curved rod is found in diverse aquatic ecosystems around the planet. it is classified according to its major surface antigen into around 206 serogroups, of which o1 and o139 cause epidemic cholera. a recent spatial modelling technique estimated that around 2.86 million cholera cases occur globally every year, and of them approximately 95,000 die. about 1.3 billion people are currently at risk of infection from cholera. meta-analysis and mathema ...201728270154
the proximity of ribosomal protein genes to oric enhances vibrio cholerae fitness in the absence of multifork replication.recent works suggest that bacterial gene order links chromosome structure to cell homeostasis. comparative genomics showed that, in fast-growing bacteria, ribosomal protein genes (rp) locate near the replication origin (oric). we recently showed that vibrio cholerae employs this positional bias as a growth optimization strategy: under fast-growth conditions, multifork replication increases rp dosage and expression. however, rp location may provide advantages in a dosage-independent manner: for e ...201728246358
transcriptional and post-transcriptional regulation of pst2 operon expression in vibrio cholerae o1.one of the most abundant proteins in v. cholerae o1 cells grown under inorganic phosphate (pi) limitation is psts, the periplasmic pi-binding component of the high-affinity pi transport system pst2 (pstscab), encoded in pst2 operon (psts-pstc2-psta2-pstb2). besides its role in pi uptake, pst2 has been also associated with v. cholerae virulence. however, the mechanisms regulating pst2 expression and the non-stoichiometric production of the pst2 components under pi-limitation are unknown. a comput ...201728242357
differential regulation of riboflavin supply genes in vibrio cholerae.riboflavin is the precursor of important redox cofactors such as flavin mononucleotide (fmn) and flavin adenine dinucleotide, required for several biological processes. vibrio cholerae, a pathogenic bacterium responsible for the cholera disease, possesses the ability to biosynthesize de novo as well as to uptake riboflavin through the riboflavin biosynthetic pathway (rbp) and the ribn importer, respectively. the intra-organism relationship between riboflavin biosynthesis and uptake functions has ...201728239422
structural and biochemical studies on vibrio cholerae hsp31 reveals a novel dimeric form and glutathione-independent glyoxalase activity.vibrio cholerae experiences a highly hostile environment at human intestine which triggers the induction of various heat shock genes. the hcha gene product of v. cholerae o395, referred to a hypothetical intracellular protease/amidase vchsp31, is one such stress-inducible homodimeric protein. our current study demonstrates that vchsp31 is endowed with molecular chaperone, amidopeptidase and robust methylglyoxalase activities. through site directed mutagenesis coupled with biochemical assays on v ...201728235098
whole-genome sequencing of vibrio cholerae o1 el tor strains isolated in ukraine (2011) and russia (2014).here, we present the draft whole-genome sequence of vibrio cholerae o1 el tor strains 76 and m3265/80, isolated in mariupol, ukraine, and moscow, russia. the presence of various mutations detected in virulence-associated mobile elements indicates high genetic similarity of the strains reported here with new highly virulent variants of the cholera agent v. cholerae.201728232438
genetic characterization of vibrio cholerae o1 isolates from outbreaks between 2011 and 2015 in tanzania.cholera outbreaks have occurred in tanzania since 1974. to date, the genetic epidemiology of these outbreaks has not been assessed.201728219321
structure and function of vibrio cholerae accessory cholera enterotoxin in presence of gold nanoparticles: dependence on morphology.accessory cholera enterotoxin (ace) is a classical enterotoxin produced by vibrio cholerae, the causative agent for cholera. considering the crucial role of ace in pathogenesis of cholera, we explored the modulation of structure/function of ace using gold nanoparticles (aunps) of different size and shape - spherical (auns10 and auns100, the number indicating the diameter in nm) and rod (aunr10).201728215703
replication of vibrio cholerae classical ctx phage.the toxigenic classical and el tor biotype vibrio cholerae serogroup o1 strains are generated by lysogenization of host-type-specific cholera toxin phages (ctx phages). experimental evidence of the replication and transmission of an el tor biotype-specific ctx phage, ctx-1, has explained the evolution of v. cholerae el tor biotype strains. the generation of classical biotype strains has not been demonstrated in the laboratory, and the classical biotype-specific ctx phage, ctx-cla, is considered ...201728196886
systematic genetic dissection of pts in vibrio cholerae uncovers a novel glucose transporter and a limited role for pts during infection of a mammalian host.a common mechanism for high affinity carbohydrate uptake in microbial species is the phosphoenolpyruvate-dependent phosphotransferase system (pts). this system consists of a shared component, ei, which is required for all pts transport, and numerous carbohydrate uptake transporters. in vibrio cholerae, there are 13 distinct pts transporters. due to genetic redundancy within this system, the carbohydrate specificity of each of these transporters is not currently defined. here, using multiplex gen ...201728196401
comparative genome analysis of vsp-ii and snps reveals heterogenic variation in contemporary strains of vibrio cholerae o1 isolated from cholera patients in kolkata, india.cholera is an acute diarrheal disease and a major public health problem in many developing countries in asia, africa, and latin america. since the bay of bengal is considered the epicenter for the seventh cholera pandemic, it is important to understand the genetic dynamism of vibrio cholerae from kolkata, as a representative of the bengal region. we analyzed whole genome sequence data of v. cholerae o1 isolated from cholera patients in kolkata, india, from 2007 to 2014 and identified the heterog ...201728192431
evolution of the immune response against recombinant proteins (tcpa, tcpb, and flaa) as a candidate subunit cholera vaccine.vibrio cholerae is the causative agent of cholera and annually leads to death of thousands of people around the globe. two factors in the pathogenesis of this bacterium are its pili and flagella. the main subunits of pili tcpa, tcpb, and flaa are the constituent subunit of flagella. in this study, we studied the ability of pili and flagella subunits to stimulate immune responses in mice. after amplification of tcpa, tcpb, and flaa genes using pcr, they were cloned in expression plasmids. after p ...201728191473
conjugate vaccines from bacterial antigens by squaric acid chemistry: a closer look.by using o-sp-core (o-spcnh2 ) polysaccharide, isolated from vibrio cholera o1 lipopolysaccharide (lps) and related synthetic substances, a detailed study of factors that affect conjugation of bacterial polysaccharides to protein carriers through squaric acid chemistry to form conjugate vaccines has been carried out. several previously unrecognized processes that take place during the squarate labeling of the o-spcnh2 and subsequent conjugation of the formed squarate (o-spcnh-sqome) have been id ...201728182850
the ins and outs of cyclic di-gmp signaling in vibrio cholerae.the second messenger nucleotide cyclic dimeric guanosine monophosphate (c-di-gmp) governs many cellular processes in the facultative human pathogen vibrio cholerae. this organism copes with changing environmental conditions in aquatic environments and during transitions to and from human hosts. modulation of c-di-gmp allows v. cholerae to shift between motile and sessile stages of life, thus allowing adaptation to stressors and environmental conditions during its transmission cycle. the v. chole ...201728171809
insights into the ion-coupling mechanism in the mate transporter norm-vc.bacteria have developed a variety of different mechanisms to defend themselves from compounds that are toxic to them, such as antibiotics. one of these defence mechanisms is the expulsion of drugs or other noxious compounds by multidrug efflux pumps. multidrug and toxic compound extrusion (mate) transporters are efflux pumps that extrude metabolic waste and a variety of antibiotics out of the cell, using an ion gradient as energy source. they function via an alternative-access mechanism. when io ...201728169223
paxvax cvd 103-hgr single-dose live oral cholera vaccine.cholera remains a problem in developing countries and a risk for travelers. hypochlorhydria, blood group o, cardiac and renal disease increase the risk of developing cholera gravis. oral vaccines containing inactivated vibrio cholerae and requiring two doses are available in some countries. no cholera vaccine had been available for u.s. travelers for decades until 2016 when cvd 103-hgr (vaxchora™), an oral live attenuated vaccine, was licensed by the u.s. fda. areas covered: enduring protection ...201728165831
architecture of the vibrio cholerae toxin-coregulated pilus machine revealed by electron cryotomography.type iv pili (t4p) are filamentous appendages found on many bacteria and archaea. they are helical fibres of pilin proteins assembled by a multi-component macromolecular machine we call the basal body. based on pilin features, t4p are classified into type iva pili (t4ap) and type ivb pili (t4bp)(1,2). t4ap are more widespread and are involved in cell motility(3), dna transfer(4), host predation(5) and electron transfer(6). t4bp are less prevalent and are mainly found in enteropathogenic bacteria ...201728165453
killing by type vi secretion drives genetic phase separation and correlates with increased cooperation.by nature of their small size, dense growth and frequent need for extracellular metabolism, microbes face persistent public goods dilemmas. genetic assortment is the only general solution stabilizing cooperation, but all known mechanisms structuring microbial populations depend on the availability of free space, an often unrealistic constraint. here we describe a class of self-organization that operates within densely packed bacterial populations. through mathematical modelling and experiments w ...201728165005
oxyr-activated expression of dps is important for vibrio cholerae oxidative stress resistance and pathogenesis.vibrio cholerae is the causative agent of cholera, a dehydrating diarrheal disease. this gram-negative pathogen is able to modulate its gene expression in order to combat stresses encountered in both aquatic and host environments, including stress posed by reactive oxygen species (ros). in order to further the understanding of v. cholerae's transcriptional response to ros, we performed an rna sequencing analysis to determine the transcriptional profile of v. cholerae when exposed to hydrogen hyd ...201728151956
a cocktail of three virulent bacteriophages prevents vibrio cholerae infection in animal models.effective prevention strategies will be essential in reducing disease burden due to bacterial infections. here we harness the specificity and rapid-acting properties of bacteriophages as a potential prophylaxis therapy for cholera, a severely dehydrating disease caused by vibrio cholerae. to this end, we test a cocktail of three virulent phages in two animal models of cholera pathogenesis (infant mouse and rabbit models). oral administration of the phages up to 24 h before v. cholerae challenge ...201728146150
oxyr2 modulates oxyr1 activity and vibrio cholerae oxidative stress response.bacteria have developed capacities to deal with different stresses and adapt to different environmental niches. the human pathogen vibrio cholerae, the causative agent of the severe diarrheal disease cholera, utilizes the transcriptional regulator oxyr to activate genes related to oxidative stress resistance, including peroxiredoxin prxa, in response to hydrogen peroxide. in this study, we identified another oxyr homolog in v. cholerae, which we named oxyr2, and we renamed the previous oxyr oxyr ...201728138024
tracking disease: digital epidemiology offers new promise in predicting outbreaks.on 19 october 2010, ten months after a devastating earthquake hit haiti, the haitian ministry of public health and population (mspp) was notified of a sudden surge in patients suffering from watery diarrhea and dehydration. two days later, the haiti national public health laboratory identified the culprit: vibrio cholerae. on 22 october, officials announced the first cholera outbreak in haiti in more than a century.201728129137
biochemical basis for activation of virulence genes by bile salts in vibrio parahaemolyticus.bile salts act as a stressor to bacteria that transit the intestinal tract. enteric pathogens have hijacked bile as an intestinal signal to regulate virulence factors. we recently demonstrated that vibrio parahemolyticus senses bile salts via a heterodimeric receptor formed by the periplasmic domains of inner-membrane proteins vtra and vtrc. crystal structures of the periplasmic complex reveal that vtra and vtrc form a β-barrel that binds bile salts in its hydrophobic interior to activate the vt ...201728129014
flufenamic acid protects against intestinal fluid secretion and barrier leakage in a mouse model of vibrio cholerae infection through nf-κb inhibition and ampk activation.nuclear factor kappa b (nf-κb)-mediated inflammatory responses play crucial roles in the pathogenesis of diarrhea caused by the vibrio cholerae el tor variant (el), which is a major bacterial strain causing recent cholera outbreaks. flufenamic acid (ffa) has previously been demonstrated to be a potent activator of amp-activated protein kinase (ampk), which is a negative regulator of nf-κb signaling. this study aimed to investigate the anti-diarrheal efficacy of ffa in a mouse model of el infecti ...201728119077
the fatty acid regulator fadr influences the expression of the virulence cascade in the el tor biotype of vibrio cholerae by modulating the levels of toxt via two different mechanisms.fadr is a master regulator of fatty acid (fa) metabolism that coordinates the pathways of fa degradation and biosynthesis in enteric bacteria. we show here that a δfadr mutation in the el tor biotype of vibrio cholerae prevents the expression of the virulence cascade by influencing both the transcription and the posttranslational regulation of the master virulence regulator toxt. fadr is a transcriptional regulator that represses the expression of genes involved in fa degradation, activates the ...201728115548
characterization and genetic variation of vibrio cholerae isolated from clinical and environmental sources in thailand.cholera is still an important public health problem in several countries, including thailand. in this study, a collection of clinical and environmental v. cholerae serogroup o1, o139, and non-o1/non-o139 strains originating from thailand (1983 to 2013) was characterized to determine phenotypic and genotypic traits and to investigate the genetic relatedness. using a combination of conventional methods and whole genome sequencing (wgs), 78 v. cholerae strains were identified. wgs was used to deter ...201728103259
merr and chrr mediate blue light induced photo-oxidative stress response at the transcriptional level in vibrio cholerae.blue light (bl) is a major environmental factor that affects the physiology, behavior, and infectivity of bacteria as it contributes to the generation of reactive oxygen species (ros) while increasing photo-oxidative stress in cells. however, precise photo-oxidative response mechanism in non-phototrophic bacteria is yet to be elucidated. in this study, we investigated the effect of bl in vibrio cholerae by using genetics and transcriptome profiling. genome-wide analysis revealed that transcripti ...201728098242
unraveling the stereochemical and dynamic aspects of the catalytic site of bacterial peptidyl-trna hydrolase.bacterial peptidyl-trna hydrolase (pth; ec 3.1.1.29) hydrolyzes the peptidyl-trnas accumulated in the cytoplasm and thereby prevents cell death by alleviating trna starvation. x-ray and nmr studies of vibrio cholerae pth (vcpth) and mutants of its key residues involved in catalysis show that the activity and selectivity of the protein depends on the stereochemistry and dynamics of residues h24, d97, n118, and n14. d97-h24 interaction is critical for activity because it increases the nucleophilic ...201728096445
vibrio cholerae cholix toxin-induced hepg2 cell death is enhanced by tumor necrosis factor-alpha through ros and intracellular signal-regulated kinases.cholix toxin (cholix) from vibrio cholerae is a potent virulence factor exhibiting adp-ribosyltransferase activity on eukaryotic elongation factor 2 (eef2) of host cells, resulting in inhibition of protein synthesis. administration of cholix or its homologue pseudomonas exotoxin a (pea) to mice causes lethal hepatocyte damage. in this study, we demonstrate cytotoxicity of cholix on immortalized human hepatocytes in the presence of tumor necrosis factor α (tnf-α), which has been reported to play ...201728087840
a periplasmic polymer curves vibrio cholerae and promotes pathogenesis.pathogenic vibrio cholerae remains a major human health concern. v. cholerae has a characteristic curved rod morphology, with a longer outer face and a shorter inner face. the mechanism and function of this curvature were previously unknown. here, we identify and characterize crva, the first curvature determinant in v. cholerae. crva self-assembles into filaments at the inner face of cell curvature. unlike traditional cytoskeletons, crva localizes to the periplasm and thus can be considered a pe ...201728086090
physiology of the vc-nhap paralogous group of cation-proton antiporters in vibrio cholerae.the genome of vibrio cholerae encodes three cation-proton antiporters of nhap-type, vc-nhap1, 2, and 3. to examine physiological roles of vc-nhap antiporters, triple δnhap1δnhap2δnhap3 and single δnhap3 deletion mutants of v. cholerae were constructed and characterized. vc-nhap3 was, for the first time, cloned and biochemically characterized. activity measurements on the inside-out membrane vesicle experimental model defined vc-nhap3 as a potassium-specific cation-proton antiporter. while elimin ...201728083717
peldor spectroscopy reveals two defined states of a sialic acid trap transporter sbp in solution.the tripartite atp-independent periplasmic (trap) transporters are a widespread class of membrane transporters in bacteria and archaea. typical substrates for trap transporters are organic acids including the sialic acid n-acetylneuraminic acid. the substrate binding proteins (sbp) of trap transporters are the best studied component and are responsible for initial high-affinity substrate binding. to better understand the dynamics of the ligand binding process, pulsed electron-electron double res ...201728076802
distribution of resistance genetic determinants among vibrio cholerae isolates of 2012 and 2013 outbreaks in ir iran.the objective of this study was to characterize antimicrobial resistance determinants in relation to antimicrobial susceptibility and genotyping profile in 20 clinical isolates of vibrio cholerae. all of the isolates were resistant to streptomycin. the second most prevalent resistance was observed to trimethoprim (75%), co-trimoxazole (60%), tetracycline (50%), and minocycline (45%). about 50% of the isolates fulfilled the criteria of multi drug resistance (mdr) phenotype. none of the isolates c ...201728062293
glycosylation characterization of an influenza h5n7 hemagglutinin series with engineered glycosylation patterns: implications for structure-function relationships.the glycosylation patterns of four recombinant h5 hemagglutinins (has) derived from a/mallard/denmark/64650/03 (h5n7) have been characterized. the proteins were expressed in (i) hek293t cells to produce complex glycoforms, (ii) hek293t cells treated with vibrio cholera neuraminidase to provide asialo-complex glycoforms, (iii) hek293s gnti(-) cells with predominantly the canonical man5glcnac2 glycoform, and (iv) drosophila s2 insect cells producing primarily paucimannose glycoforms. previously, t ...201728060516
new ligation independent cloning vectors for expression of recombinant proteins with a self-cleaving cpd/6xhis-tag.recombinant protein purification is a crucial step for biochemistry and structural biology fields. rapid robust purification methods utilize various peptide or protein tags fused to the target protein for affinity purification using corresponding matrices and to enhance solubility. however, affinity/solubility-tags often need to be removed in order to conduct functional and structural studies, adding complexities to purification protocols.201728056928
identification of the catalytic ubiquinone-binding site of vibrio cholerae sodium-dependent nadh dehydrogenase: a novel ubiquinone-binding motif.the sodium-dependent nadh dehydrogenase (na(+)-nqr) is a key component of the respiratory chain of diverse prokaryotic species, including pathogenic bacteria. na(+)-nqr uses the energy released by electron transfer between nadh and ubiquinone (uq) to pump sodium, producing a gradient that sustains many essential homeostatic processes as well as virulence factor secretion and the elimination of drugs. the location of the uq binding site has been controversial, with two main hypotheses that sugges ...201728053088
vibrio mimicus as the rare cause of acute diarrheal illness.vibrio mimicus, although named for having many of the same virulent factors as vibrio cholera, is a rare cause of significant gastrointestinal illness. like many of the vibrio species, the strongest risk factor for v. mimicus infection is seafood consumption. after consuming crabs, a 64-year-old male presented with a three day history of voluminous, non-bloody, water diarrhea. the severity of the diarrhea caused the patient to have orthostatic hypotension and acute kidney injury, which improved ...201728045686
resource abundance and the critical transition to cooperation.cooperation is abundant in nature, occurring at all levels of biological complexity. yet cooperation is continually threatened by subversion from noncooperating cheaters. previous studies have shown that cooperation can nevertheless be maintained when the benefits that cooperation provides to relatives outweigh the associated costs. these fitness costs and benefits are not fixed properties, but can be affected by the environment in which populations reside. here, we describe how one environmenta ...201728036143
genetically encodable bacterial flavin transferase for fluorogenic protein modification in mammalian cells.a bacterial flavin transferase (apbe) was recently employed for flavin mononucleotide (fmn) modification on the na(+)-translocating nadh:quinone oxidoreductase c (nqrc) protein in the pathogenic gram-negative bacterium vibrio cholerae. we employed this unique post-translational modification in mammalian cells and found that the fmn transfer reaction robustly occurred when nqrc and apbe were genetically targeted in the cytosol of live mammalian cells. moreover, nqrc expression in the endoplasmic ...201728035820
elucidation of the tidal influence on bacterial populations in a monsoon influenced estuary through simultaneous observations.the influence of tides on bacterial populations in a monsoon influenced tropical estuary was assessed through fine resolution sampling (1 to 3 h) during spring and neap tides from mouth to the freshwater end at four stations during pre-monsoon, monsoon and post-monsoon seasons. higher abundance of total bacterial count (tbc) in surface water near the river mouth, compared to the upstream, during pre-monsoon was followed by an opposite scenario during the monsoon when seasonally compared, it was ...201728035613
application of a paper based device containing a new culture medium to detect vibrio cholerae in water samples collected in haiti.cholera is now considered to be endemic in haiti, often with increased incidence during rainy seasons. the challenge of cholera surveillance is exacerbated by the cost of sample collection and laboratory analysis. a diagnostic tool is needed that is low cost, easy-to-use, and able to detect and quantify vibrio cholerae accurately in water samples within 18-24h, and perform reliably in remote settings lacking laboratory infrastructure and skilled staff. the two main objectives of this study were ...201728007529
efficient and flexible preparation of biosynthetic microperoxidases.heme peptides and their derivatives, also called microperoxidases (mps), are employed as heme protein active site models, catalysts, and charge-transfer chromophores. in this work, two approaches to the biosynthesis of novel mps are described. in one method, heme peptides are expressed as c-terminal tags to the protein azurin and the mp is liberated by proteolytic cleavage by an endopeptidase. in an alternative approach, heme peptides are expressed as n-terminal tags to the cysteine protease dom ...201727957837
genomic profile of antibiotic resistant, classical ctxb positive vibrio cholerae o1 biotype el tor isolated in 2003 and 2005 from puri, india: a retrospective study.to examine eight strains of vibrio cholerae o1 isolated in 2003 and 2005 from puri, india, for antibiotic susceptibility, presence of virulence and regulatory genes, cholera toxin (ct) production, ctx arrangement and genomic profiles.201727934824
kinetics of antibody-secreting cell and fecal iga responses after oral cholera vaccination in different age groups in a cholera endemic country.immune responses to oral enteric vaccines in children and infants may be influenced by factors such as age, previous priming with related microorganisms and breast feeding. in this study, we aimed to determine optimal time points to assess immune responses to oral enteric vaccines in different clinical specimens. this was done by investigating antibody secreting cell (asc) and fecal antibody responses on different days after vaccination using the licensed oral cholera vaccine dukoral, containing ...201727916412
rules of engagement: the type vi secretion system in vibrio cholerae.microbial species often exist in complex communities where they must avoid predation and compete for favorable niches. the type vi secretion system (t6ss) is a contact-dependent bacterial weapon that allows for direct killing of competitors through the translocation of proteinaceous toxins. vibrio cholerae is a gram-negative pathogen that can use its t6ss during antagonistic interactions with neighboring prokaryotic and eukaryotic competitors. the t6ss not only promotes v. cholerae's survival du ...201728027803
in-silico prediction of dual function of dksa like hypothetical protein in v. cholerae o395 genome.cholera, an acute infection of the small intestine, is caused by vibrio cholerae. the present study identified a hypothetical protein in v. cholerae o395, which was predicted to be acquired through horizontal gene transfer the origin of which was found to be from a phage. its expression was further confirmed by rt-pcr. homology based 3d model of the hypothetical protein indicated dksa like homologue. protein binding site of 3d-model revealed a deep cleft which may influence the dimer formation a ...201728024527
whole-genome enrichment provides deep insights into vibrio cholerae metagenome from an african river.the detection and typing of vibrio cholerae in natural aquatic environments encounter major methodological challenges related to the fact that the bacterium is often present in environmental matrices at very low abundance in nonculturable state. this study applied, for the first time to our knowledge, a whole-genome enrichment (wge) and next-generation sequencing (ngs) approach for direct genotyping and metagenomic analysis of low abundant v. cholerae dna (<50 genome unit/l) from natural water c ...201727888291
biogeochemical and hydrological drivers of the dynamics of vibrio species in two patagonian estuaries.the ecology of the most relevant vibrio species for human health and their relation to water quality and biogeochemistry were studied in two estuaries in argentinian patagonia. vibrio cholerae and vibrio parahaemolyticus were reported in >29% of cases at the río colorado and río negro estuaries. neither the pandemic serogroups of vibrio cholerae o1, vibrio cholerae o139 nor the cholera toxin gene were detected in this study. however, several strains of v. cholerae (not o1 or o139) are able to ca ...201727871750
high genetic diversity of vibrio cholerae in the european lake neusiedler see is associated with intensive recombination in the reed habitat and the long-distance transfer of strains.coastal marine vibrio cholerae populations usually exhibit high genetic diversity. to assess the genetic diversity of abundant v. cholerae non-o1/non-o139 populations in the central european lake neusiedler see, we performed a phylogenetic analysis based on reca, toxr, gyrb and pyrh loci sequenced for 472 strains. the strains were isolated from three ecologically different habitats in a lake that is a hot-spot of migrating birds and an important bathing water. we also analyzed 76 environmental a ...201727871138
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