Sample records for bacterium vibrio harveyi

  1. Tryptophan biosynthesis in the marine luminous bacterium Vibrio harveyi.

    PubMed Central

    Bieger, C D; Crawford, I P

    1983-01-01

    Tryptophan biosynthetic enzyme levels in wild-type Vibrio harveyi and a number of tryptophan auxotrophs of this species were coordinately regulated over a 100-fold range of specific activities. The tryptophan analog indoleacrylic acid evoked substantial derepression of the enzymes in wild-type cells. Even higher enzyme levels were attained in auxotrophs starved for tryptophan, regardless of the location of the block in the pathway. A derepressed mutant selected by resistance to 5-fluorotryptophan was found to have elevated basal levels of trp gene expression; these basal levels were increased only two- to threefold by tryptophan limitation. The taxonomic implications of these and other biochemical results support previous suggestions that the marine luminous bacteria are more closely related to enteric bacteria than to other gram-negative taxa. PMID:6822478

  2. Cross-Species Induction of Luminescence in the Quorum Sensing Bacterium Vibrio harveyi

    Microsoft Academic Search

    BONNIE L. BASSLER; E. PETER GREENBERG; ANN M. STEVENS

    1997-01-01

    At least two species of marine bacteria, Vibrio fischeri and Vibrio harveyi, express bioluminescence in response to cell den- sity. These two vibrios are found in different environments in the ocean. V. harveyi is found free-living in the sea as well as in the gut tracts of marine animals, where it exists at high popu- lation densities in association with

  3. Complete Genome Sequence of the Bioluminescent Marine Bacterium Vibrio harveyi ATCC 33843 (392 [MAV])

    PubMed Central

    Wang, Zheng; Hervey, W. Judson; Kim, Seongwon; Lin, Baochuan

    2015-01-01

    Vibrio harveyi is a Gram-negative marine ?-proteobacterium that is known to be a formidable pathogen of aquatic animals and is a model organism for the study of bacterial bioluminescence and quorum sensing. In this report, we describe the complete genome sequence of the most studied strain of this species: V. harveyi ATCC 33843 (392 [MAV]). PMID:25635019

  4. Molecular Uptake of Chitooligosaccharides through Chitoporin from the Marine Bacterium Vibrio harveyi

    PubMed Central

    Suginta, Wipa; Chumjan, Watcharin; Mahendran, Kozhinjampara R.; Janning, Petra; Schulte, Albert; Winterhalter, Mathias

    2013-01-01

    Background Chitin is the most abundant biopolymer in marine ecosystems. However, there is no accumulation of chitin in the ocean-floor sediments, since marine bacteria Vibrios are mainly responsible for a rapid turnover of chitin biomaterials. The catabolic pathway of chitin by Vibrios is a multi-step process that involves chitin attachment and degradation, followed by chitooligosaccharide uptake across the bacterial membranes, and catabolism of the transport products to fructose-6-phosphate, acetate and NH3. Principal Findings This study reports the isolation of the gene corresponding to an outer membrane chitoporin from the genome of Vibrio harveyi. This porin, expressed in E. coli, (so called VhChiP) was found to be a SDS-resistant, heat-sensitive trimer. Immunoblotting using anti-ChiP polyclonal antibody confirmed the expression of the recombinant ChiP, as well as endogenous expression of the native protein in the V. harveyi cells. The specific function of VhChiP was investigated using planar lipid membrane reconstitution technique. VhChiP nicely inserted into artificial membranes and formed stable, trimeric channels with average single conductance of 1.8±0.13 nS. Single channel recordings at microsecond-time resolution resolved translocation of chitooligosaccharides, with the greatest rate being observed for chitohexaose. Liposome swelling assays showed no permeation of other oligosaccharides, including maltose, sucrose, maltopentaose, maltohexaose and raffinose, indicating that VhChiP is a highly-specific channel for chitooligosaccharides. Conclusion/Significance We provide the first evidence that chitoporin from V. harveyi is a chitooligosaccharide specific channel. The results obtained from this study help to establish the fundamental role of VhChiP in the chitin catabolic cascade as the molecular gateway that Vibrios employ for chitooligosaccharide uptake for energy production. PMID:23383078

  5. Quorum Sensing Regulates Type III Secretion in Vibrio harveyi and Vibrio parahaemolyticus

    PubMed Central

    Henke, Jennifer M.; Bassler, Bonnie L.

    2004-01-01

    In a process known as quorum sensing, bacteria communicate with one another by producing, releasing, detecting, and responding to signal molecules called autoinducers. Vibrio harveyi, a marine pathogen, uses two parallel quorum-sensing circuits, each consisting of an autoinducer-sensor pair, to control the expression of genes required for bioluminescence and a number of other target genes. Genetic screens designed to discover autoinducer-regulated targets in V. harveyi have revealed genes encoding components of a putative type III secretion (TTS) system. Using transcriptional reporter fusions and TTS protein localization studies, we show that the TTS system is indeed functional in V. harveyi and that expression of the genes encoding the secretion machinery requires an intact quorum-sensing signal transduction cascade. The newly completed genome of the closely related marine bacterium Vibrio parahaemolyticus, which is a human pathogen, shows that it possesses the genes encoding both of the V. harveyi-like quorum-sensing signaling circuits and that it also has a TTS system similar to that of V. harveyi. We show that quorum sensing regulates TTS in V. parahaemolyticus. Previous reports connecting quorum sensing to TTS in enterohemorrhagic and enteropathogenic Escherichia coli show that quorum sensing activates TTS at high cell density. Surprisingly, we find that at high cell density (in the presence of autoinducers), quorum sensing represses TTS in V. harveyi and V. parahaemolyticus. PMID:15175293

  6. Influence of nitrogen substrates and substrate C:N ratios on the nitrogen isotopic composition of amino acids from the marine bacterium Vibrio harveyi

    NASA Astrophysics Data System (ADS)

    Maki, K.; Ohkouchi, N.; Chikaraishi, Y.; Fukuda, H.; Miyajima, T.; Nagata, T.

    2014-09-01

    Nitrogen (N) isotopic compositions of individual hydrolysable amino acids (?15NAAs) in N pools have been increasingly used for trophic position assessment and evaluation of sources and transformation processes of organic matter in marine environments. However, there are limited data about variability in ?15NAAs patterns and how this variability influences marine bacteria, an important mediator of trophic transfer and organic matter transformation. We explored whether marine bacterial ?15NAAs profiles change depending on the type and C:N ratio of the substrate. The ?15NAAs profile of a marine bacterium, Vibrio harveyi, was examined using medium containing either glutamate, alanine or ammonium as the N source [substrate C:N ratios (range, 3 to 20) were adjusted with glucose]. The data were interpreted as a reflection of isotope fractionations associated with de novo synthesis of amino acids by bacteria. Principal component analysis (PCA) using the ?15N offset values normalized to glutamate + glutamine ?15N revealed that ?15NAAs profiles differed depending on the N source and C:N ratio of the substrate. High variability in the ?15N offset of alanine and valine largely explained this bacterial ?15NAAs profile variability. PCA was also conducted using bacterial and phytoplankton (cyanobacteria and eukaryotic algae) ?15NAAs profile data reported previously. The results revealed that bacterial ?15NAAs patterns were distinct from those of phytoplankton. Therefore, the ?15NAAs profile is a useful indicator of biochemical responses of bacteria to changes in substrate conditions, serving as a potentially useful method for identifying organic matter sources in marine environments.

  7. Three Parallel Quorum-Sensing Systems Regulate Gene Expression in Vibrio harveyi

    Microsoft Academic Search

    Jennifer M. Henke; Bonnie L. Bassler

    2004-01-01

    In a process called quorum sensing, bacteria communicate using extracellular signal molecules termed auto- inducers. Two parallel quorum-sensing systems have been identified in the marine bacterium Vibrio harveyi. System 1 consists of the LuxM-dependent autoinducer HAI-1 and the HAI-1 sensor, LuxN. System 2 consists of the LuxS-dependent autoinducer AI-2 and the AI-2 detector, LuxPQ. The related bacterium, Vibrio cholerae, a

  8. Genetically modified Vibrio harveyi strains as potential bioindicators of mutagenic pollution of marine environments

    SciTech Connect

    Czyz, A.; Jasiecki, J.; Bogdan, A.; Szpilewska, H.; Wegrzyn, G.

    2000-02-01

    For biodetection of mutagenic pollution of marine environments, an organism naturally occurring in these habitats should be used. The authors found that marine bacterium Vibrio harveyi may be an appropriate bioindicator of mutagenic pollution. For positive selection of mutants, they developed a simple method for isolation of V. harveyi mutants resistant to neomycin. The authors constructed genetically modified V. harveyi strains that produce significantly more neomycin-resistant mutants upon treatment with low concentrations of mutagens than the wild-type counterpart. The sensitivity of the mutagenicity test with the V. harveyi strains is at least comparable to (if not higher than) that of the commonly used Ames test, which uses Salmonella enterica serovar Typhimurium strains. Therefore, the authors consider that the V. harveyi strains described in this report could be used as potential bioindicators of mutagenic pollution of marine environments.

  9. Complementation studies of the DnaK–DnaJ–GrpE chaperone machineries from Vibrio harveyi and Escherichia coli , both in vivo and in vitro

    Microsoft Academic Search

    Micha? A. ?mijewski; Joanna M. Kwiatkowska; Barbara Lipi?ska

    2004-01-01

    The marine bacterium Vibrio harveyi is a potential indicator organism for evaluating marine environmental pollution. The DnaK–DnaJ–GrpE chaperone machinery of V. harveyi has been studied as a model of response to stress conditions and compared to the Escherichia coli DnaK system. The genes encoding DnaK, DnaJ and GrpE of V. harveyi were cloned into expression vectors and grpE was sequenced.

  10. Differences in nucleotide specificity and catalytic mechanism between Vibrio harveyi aldehyde dehydrogenase and other members of the aldehyde dehydrogenase superfamily

    Microsoft Academic Search

    Lei Zhang; Bijan Ahvazi; Rose Szittner; Alice Vrielink; Edward Meighen

    2001-01-01

    The fatty aldehyde dehydrogenase (Vh-ALDH) isolated from the luminescent bacterium, Vibrio harveyi, differs from other aldehyde dehydrogenases in its high affinity for NADP+. The binding of NADP+ appears to arise from the interaction of the 2?-phosphate of the adenosine moiety of NADP+ with a threonine (T175) in the nucleotide recognition site just after the ?B strand as well as with

  11. Simulated hatchery system to assess bacteriophage efficacy against Vibrio harveyi.

    PubMed

    Raghu Patil, J; Desai, Srividya Narayanamurthy; Roy, Panchali; Durgaiah, Murali; Saravanan, R Sanjeev; Vipra, Aradhana

    2014-12-01

    Vibriosis caused by luminous Vibrio harveyi commonly contributes to poor survival in shrimp hatcheries and aquaculture ponds. Lytic bacteriophages pathogenic for V. harveyi are currently being investigated as an alternative to antibiotics to prevent vibriosis. Here, 8 bacteriophages were isolated from oysters and clams using V. harveyi strains as baiting hosts. Among these bacteriophages, 1 strain (VHP6b) identified as broadly pathogenic for 27 V. harveyi strains examined was further characterized by electron microscopy and genome sequence analysis. Phage VHP6b possessed a tail and morphology consistent with it being a member of the family Siphoviridae, and its genome and proteome were most closely related to the Vibrio phages SSP02 and MAR10. An integrase gene essential for lysogeny was not evident. The ability of bacteriophage VHP6b to protect shrimp postlarvae against vibriosis caused by V. harveyi strain VH6 was demonstrated in a model system designed to simulate typical hatchery conditions. Bacteriophage treatment improved survival of postlarvae by 40 to 60% under these conditions, so therapies based on this or other bacteriophages may be useful in shrimp hatcheries. PMID:25449322

  12. Regulation of Metalloprotease Gene Expression in Vibrio vulnificus by a Vibrio harveyi LuxR Homologue

    Microsoft Academic Search

    CHUNG-PING SHAO; LIEN-I HOR

    2001-01-01

    Expression of the Vibrio vulnificus metalloprotease gene, vvp, was turned up rapidly when bacterial growth reached the late log phase. A similar pattern of expression has been found in the metalloprotease gene of Vibrio cholerae, and this has been shown to be regulated by a Vibrio harveyi LuxR-like transcriptional activator. To find out whether a LuxR homologue exists in V.

  13. Active regulation of receptor ratios controls integration of quorum-sensing signals in Vibrio harveyi

    PubMed Central

    Teng, Shu-Wen; Schaffer, Jessica N; Tu, Kimberly C; Mehta, Pankaj; Lu, Wenyun; Ong, N P; Bassler, Bonnie L; Wingreen, Ned S

    2011-01-01

    Quorum sensing is a chemical signaling mechanism used by bacteria to communicate and orchestrate group behaviors. Multiple feedback loops exist in the quorum-sensing circuit of the model bacterium Vibrio harveyi. Using fluorescence microscopy of individual cells, we assayed the activity of the quorum-sensing circuit, with a focus on defining the functions of the feedback loops. We quantitatively investigated the signaling input–output relation both in cells with all feedback loops present as well as in mutants with specific feedback loops disrupted. We found that one of the feedback loops regulates receptor ratios to control the integration of multiple signals. Together, the feedback loops affect the input–output dynamic range of signal transmission and the noise in the output. We conclude that V. harveyi employs multiple feedback loops to simultaneously control quorum-sensing signal integration and to ensure signal transmission fidelity. PMID:21613980

  14. Biosynthesis of myristic acid in luminescent bacteria. [Vibrio harveyi

    SciTech Connect

    Byers, D.M.

    1987-05-01

    In vivo pulse-label studies have demonstrated that luminescent bacteria can provide myritic acid (14:0) required for the synthesis of the luciferase substrate myristyl aldehyde. Luminescent wild type Vibrio harveyi incubated with (/sup 14/C) acetate in a nutrient-depleted medium accumulated substantial tree (/sup 14/C)fatty acid (up to 20% of the total lipid label). Radio-gas chromatography revealed that > 75% of the labeled fatty acid is 14:0. No free fatty acid was detected in wild type cells labeled prior to the development of bioluminescence in the exponential growth phase, or in a dark mutant of V. harveyi (mutant M17) that requires exogenous 14:0 for light emission. The preferential accumulation of 14:0 was not observed when wild type cells were labeled with (/sup 14/C)acetate in regular growth medium. Moreover, all V. harveyi strains exhibited similar fatty acid mass compositions regardless of the state of bioluminescence. Since earlier work has shown that a luminescence-related acyltransferase (defective in the M17 mutant) can catalyze the deacylation of fatty acyl-acyl carrier protein in vitro, the present results are consistent with a model in which this enzyme diverts 14:0 to the luminescence system during fatty acid biosynthesis. Under normal conditions, the supply of 14:0 by this pathway is tightly regulated such that bioluminescence development does not significantly alter the total fatty acid composition.

  15. Draft genome sequence of the fish pathogen Vibrio harveyi strain ZJ0603.

    PubMed

    Huang, Yucong; Jian, Jichang; Lu, Yishan; Cai, Shuanghu; Wang, Bei; Tang, Jufen; Pang, Huanying; Ding, Yu; Wu, Zaohe

    2012-12-01

    Vibrio harveyi is an important pathogen that causes vibriosis in various aquatic organisms. Here, we announce the draft genome sequence of V. harveyi strain ZJ0603, which was isolated from diseased Orange-spotted grouper (Epinephelus coioides) in Guangdong, China. PMID:23144396

  16. Draft Genome Sequence of the Fish Pathogen Vibrio harveyi Strain ZJ0603

    PubMed Central

    Huang, Yucong; Jian, Jichang; Lu, Yishan; Cai, Shuanghu; Wang, Bei; Tang, Jufen; Pang, Huanying; Ding, Yu

    2012-01-01

    Vibrio harveyi is an important pathogen that causes vibriosis in various aquatic organisms. Here, we announce the draft genome sequence of V. harveyi strain ZJ0603, which was isolated from diseased Orange-spotted grouper (Epinephelus coioides) in Guangdong, China. PMID:23144396

  17. Comparative genomic analyses identify the Vibrio harveyi genome sequenced strains BAA-1116 and HY01 as Vibrio campbellii

    PubMed Central

    Lin, Baochuan; Wang, Zheng; Malanoski, Anthony P; O'Grady, Elizabeth A; Wimpee, Charles F; Vuddhakul, Varaporn; Alves Jr, Nelson; Thompson, Fabiano L; Gomez-Gil, Bruno; Vora, Gary J

    2010-01-01

    Three notable members of the Harveyi clade, Vibrio harveyi, Vibrio alginolyticus and Vibrio parahaemolyticus, are best known as marine pathogens of commercial and medical import. In spite of this fact, the discrimination of Harveyi clade members remains difficult due to genetic and phenotypic similarities, and this has led to misidentifications and inaccurate estimations of a species' involvement in certain environments. To begin to understand the underlying genetics that complicate species level discrimination, we compared the genomes of Harveyi clade members isolated from different environments (seawater, shrimp, corals, oysters, finfish, humans) using microarray-based comparative genomic hybridization (CGH) and multilocus sequence analyses (MLSA). Surprisingly, we found that the only two V. harveyi strains that have had their genomes sequenced (strains BAA-1116 and HY01) have themselves been misidentified. Instead of belonging to the species harveyi, they are actually members of the species campbellii. In total, 28% of the strains tested were found to be misidentified and 42% of these appear to comprise a novel species. Taken together, our findings correct a number of species misidentifications while validating the ability of both CGH and MLSA to distinguish closely related members of the Harveyi clade. PMID:20686623

  18. Association of Vibrio harveyi with mortalities in cultured marine fish in Kuwait

    Microsoft Academic Search

    M. O. Saeed

    1995-01-01

    A Vibrio sp. frequently associated with mortalities in cultured silvery black porgy Acanthopagrus cuvieri and brown-spotted grouper Epinephelus tauvina was studied. Silvery black porgy was susceptible to laboratory infection with this isolate only when administered intramuscularly (IM), but the isolate could infect brown-spotted grouper by both IM and intraperitoneal (IP) routes. The isolate was identified as Vibrio harveyi. The 5

  19. Unexpected photoreactivation of Vibrio harveyi bacteria living in ionization environment

    SciTech Connect

    Alifano, P.; Tala, A.; Tredici, S. M. [Dipartimento Microbiologia, Di.S.Te.B.A., Universita del Salento, via Provinciale Lecce-Monteroni, C.P. 193, 73100 Lecce (Italy); Nassisi, V. [Laboratorio di Elettronica Applicata e Strumentazione, LEAS, Dipartimento di Fisica, Universita del Salento and INFN-Lecce, Via Provinciale Lecce-Monteroni, 73100 Lecce (Italy); Siciliano, M. V. [Laboratorio di Elettronica Applicata e Strumentazione, LEAS, Dipartimento di Fisica, Universita del Salento and INFN-Lecce, Via Provinciale Lecce-Monteroni, 73100 Lecce (Italy); Dipartimento di Scienza dei Materiali, University of Salento, via Provinciale Lecce- Monteroni, C.P. 193, 73100 Lecce (Italy)

    2011-05-15

    Bacteria undergoing environmental effects is extremely interesting for structural, mechanistic, and evolutionary implications. Luminescent bacteria that have evolved in a specific ambient have developed particular responses and their behavior can give us new suggestions on the task and production of luciferina proteins. To analyze the UV interaction under controlled laboratory conditions, we used photoluminescent bacterial strains belonging to a new species evolutionarily close to Vibrio harveyi sampled from a coastal cave with a high radon content that generates ionizing radiation. The survival of the bacterial strains was analyzed, in the light and in the dark, following a variety of genotoxic treatments including UV radiation exposure. The strains were irradiated by a germicide lamp. The results demonstrated that most of the strains exhibited a low rate of survival after the UV exposure. After irradiation by visible light following the UV exposure, all strains showed a high capability of photoreactivation when grown. This capability was quite unexpected because these bacteria were sampled from a dark ambient without UV radiation. This leads us to hypothesize that the photoreactivation in these bacteria might have been evolved to repair DNA lesions also induced by different radiation sources other than UV (e.g., x-ray) and that the luminescent bacteria might use their own light emission to carry out the photoreactivation. The high capability of photoreactivation of these bacteria was also justified by the results of deconvolution. The deconvolution was applied to the emission spectra and it was able to show evidence of different light peaks. The presence of the visible peak could control the photolysis enzyme.

  20. Exposure to Static Magnetic Field Stimulates Quorum Sensing Circuit in Luminescent Vibrio Strains of the Harveyi Clade

    PubMed Central

    Talà, Adelfia; Delle Side, Domenico; Buccolieri, Giovanni; Tredici, Salvatore Maurizio; Velardi, Luciano; Paladini, Fabio; De Stefano, Mario; Nassisi, Vincenzo; Alifano, Pietro

    2014-01-01

    In this study, the evidence of electron-dense magnetic inclusions with polyhedral shape in the cytoplasm of Harveyi clade Vibrio strain PS1, a bioluminescent bacterium living in symbiosis with marine organisms, led us to investigate the behavior of this bacterium under exposure to static magnetic fields ranging between 20 and 2000 Gauss. When compared to sham-exposed, the light emission of magnetic field-exposed bacteria growing on solid medium at 18°C ±0.1°C was increased up to two-fold as a function of dose and growth phase. Stimulation of bioluminescence by magnetic field was more pronounced during the post-exponential growth and stationary phase, and was lost when bacteria were grown in the presence of the iron chelator deferoxamine, which caused disassembly of the magnetic inclusions suggesting their involvement in magnetic response. As in luminescent Vibrio spp. bioluminescence is regulated by quorum sensing, possible effects of magnetic field exposure on quorum sensing were investigated. Measurement of mRNA levels by reverse transcriptase real time-PCR demonstrated that luxR regulatory gene and luxCDABE operon coding for luciferase and fatty acid reductase complex were significantly up-regulated in magnetic field-exposed bacteria. In contrast, genes coding for a type III secretion system, whose expression was negatively affected by LuxR, were down-regulated. Up-regulation of luxR paralleled with down-regulation of small RNAs that mediate destabilization of luxR mRNA in quorum sensing signaling pathways. The results of experiments with the well-studied Vibrio campbellii strain BB120 (originally classified as Vibrio harveyi) and derivative mutants unable to synthesize autoinducers suggest that the effects of magnetic fields on quorum sensing may be mediated by AI-2, the interspecies quorum sensing signal molecule. PMID:24960170

  1. Construction and evaluation of a live vaccine against Edwardsiella tarda and Vibrio harveyi: Laboratory vs. mock field trial

    Microsoft Academic Search

    Yong-hua Hu; Shuang Cheng; Min Zhang; Li Sun

    2011-01-01

    Edwardsiella tarda and Vibrio harveyi are Gram-negative bacterial pathogens that affect a wide range of cultured fish. In previous studies, we have reported an E. tarda live vaccine ATCC15947 and a V. harveyi subunit vaccine DegQ. On the basis of these studies, in the present study we developed a cross protective vaccine against both E. tarda and V. harveyi by

  2. Characterization of abalone Haliotis tuberculata-Vibrio harveyi interactions in gill primary cultures.

    PubMed

    Pichon, Delphine; Cudennec, Benoit; Huchette, Sylvain; Djediat, Chakib; Renault, Tristan; Paillard, Christine; Auzoux-Bordenave, Stéphanie

    2013-10-01

    The decline of European abalone Haliotis tuberculata populations has been associated with various pathogens including bacteria of the genus Vibrio. Following the summer mortality outbreaks reported in France between 1998 and 2000, Vibrio harveyi strains were isolated from moribund abalones, allowing in vivo and in vitro studies on the interactions between abalone H. tuberculata and V. harveyi. This work reports the development of primary cell cultures from abalone gill tissue, a target tissue for bacterial colonisation, and their use for in vitro study of host cell-V. harveyi interactions. Gill cells originated from four-day-old explant primary cultures were successfully sub-cultured in multi-well plates and maintained in vitro for up to 24 days. Cytological parameters, cell morphology and viability were monitored over time using flow cytometry analysis and semi-quantitative assay (XTT). Then, gill cell cultures were used to investigate in vitro the interactions with V. harveyi. The effects of two bacterial strains were evaluated on gill cells: a pathogenic bacterial strain ORM4 which is responsible for abalone mortalities and LMG7890 which is a non-pathogenic strain. Cellular responses of gill cells exposed to increasing concentrations of bacteria were evaluated by measuring mitochondrial activity (XTT assay) and phenoloxidase activity, an enzyme which is strongly involved in immune response. The ability of gill cells to phagocyte GFP-tagged V. harveyi was evaluated by flow cytometry and gill cells-V. harveyi interactions were characterized using fluorescence microscopy and transmission electron microscopy. During phagocytosis process we evidenced that V. harveyi bacteria induced significant changes in gill cells metabolism and immune response. Together, the results showed that primary cell cultures from abalone gills are suitable for in vitro study of host-pathogen interactions, providing complementary assays to in vivo experiments. PMID:23756730

  3. Crystal structure of the NADP+-dependent aldehyde dehydrogenase from Vibrio harveyi: structural implications for cofactor specificity and affinity.

    PubMed Central

    Ahvazi, B; Coulombe, R; Delarge, M; Vedadi, M; Zhang, L; Meighen, E; Vrielink, A

    2000-01-01

    Aldehyde dehydrogenase from the bioluminescent bacterium, Vibrio harveyi, catalyses the oxidation of long-chain aliphatic aldehydes to acids. The enzyme is unique compared with other forms of aldehyde dehydrogenase in that it exhibits a very high specificity and affinity for the cofactor NADP(+). Structural studies of this enzyme and comparisons with other forms of aldehyde dehydrogenase provide the basis for understanding the molecular features that dictate these unique properties and will enhance our understanding of the mechanism of catalysis for this class of enzyme. The X-ray structure of aldehyde dehydrogenase from V. harveyi has been solved to 2.5-A resolution as a partial complex with the cofactor NADP(+) and to 2. 1-A resolution as a fully bound 'holo' complex. The cofactor preference exhibited by different forms of the enzyme is predominantly determined by the electrostatic environment surrounding the 2'-hydroxy or the 2'-phosphate groups of the adenosine ribose moiety of NAD(+) or NADP(+), respectively. In the NADP(+)-dependent structures the presence of a threonine and a lysine contribute to the cofactor specificity. In the V. harveyi enzyme an arginine residue (Arg-210) contributes to the high cofactor affinity through a pi stacking interaction with the adenine ring system of the cofactor. Further differences between the V. harveyi enzyme and other aldehyde dehydrogenases are seen in the active site, in particular a histidine residue which is structurally conserved with phosphorylating glyceraldehyde-3-phosphate dehydrogenase. This may suggest an alternative mechanism for activation of the reactive cysteine residue for nucleophilic attack. PMID:10903148

  4. Spongosine Production by a Vibrio harveyi Strain Associated with the Sponge Tectitethya crypta.

    PubMed

    Bertin, Matthew J; Schwartz, Sarah L; Lee, John; Korobeynikov, Anton; Dorrestein, Pieter C; Gerwick, Lena; Gerwick, William H

    2015-03-27

    Spongosine (1), deoxyspongosine (2), spongothymidine (Ara T) (3), and spongouridine (Ara U) were isolated from the Caribbean sponge Tectitethya crypta and given the general name "spongonucleosides". Spongosine, a methoxyadenosine derivative, has demonstrated a diverse bioactivity profile including anti-inflammatory activity and analgesic and vasodilation properties. Investigations into unusual nucleoside production by T. crypta-associated microorganisms using mass spectrometric techniques have identified a spongosine-producing strain of Vibrio harveyi and several structurally related compounds from multiple strains. PMID:25668560

  5. Substrate binding modes and anomer selectivity of chitinase A from Vibrio harveyi

    Microsoft Academic Search

    Wipa Suginta; Supansa Pantoom; Heino Prinz

    2009-01-01

    High-performance liquid chromatography mass spectrometry (HPLC MS) was employed to assess the binding behaviors of various\\u000a substrates to Vibrio harveyi chitinase A. Quantitative analysis revealed that hexaNAG preferred subsites ?2 to +2 over subsites ?3 to +2 and pentaNAG\\u000a only required subsites ?2 to +2, while subsites ?4 to +2 were not used at all by both substrates. The results

  6. Multilocus Sequence Analysis Reveals that Vibrio harveyi and V. campbellii Are Distinct Species? †

    PubMed Central

    Thompson, Fabiano L.; Gomez-Gil, Bruno; Vasconcelos, Ana Teresa Ribeiro; Sawabe, Tomoo

    2007-01-01

    Identification and classification of Vibrio species have relied upon band pattern methods (e.g., amplified fragment length polymorphism) and DNA-DNA hybridization. However, data generated by these methods cannot be used to build an online electronic taxonomy. In order to overcome these limitations, we developed the first standard multilocus sequence scheme focused on the ubiquitous and pathogenic Vibrio harveyi species group (i.e., V. harveyi, V. campbellii, V. rotiferianus, and a new as yet unnamed species). We examined a collection of 104 isolates from different geographical regions and hosts using segments of seven housekeeping genes. These two species formed separated clusters on the basis of topA, pyrH, ftsZ, and mreB gene sequences. The phylogenetic picture obtained by the other three loci, i.e., gyrB, recA, and gapA, was more complex though. V. campbellii appeared nested within V. harveyi in the recA trees, whereas V. harveyi formed a tight nested cluster within V. campbellii by gapA. The gyrB gene had no taxonomic resolution and grouped the two species together. The fuzziness observed in these three genes seems not be related to recombination but to low divergence due to the accumulation of only a few substitutions. In spite of this, the concatenated sequences provided evidence that the two species form two separated clusters. These clusters did not arise by recombination but by accumulation of point mutations. V. harveyi and V. campbellii isolates can be readily identified through the open database resource developed in this study (http://www.taxvibrio.lncc.br/). We argue that the species should be defined by evolutionary criteria. Strains of the same species will share at least 95% concatenated sequence similarity using the seven loci, and, most importantly, cospecific strains will form cohesive readily recognizable phylogenetic clades. PMID:17483280

  7. Vibrio harveyi Adheres to and Penetrates Tissues of the European Abalone Haliotis tuberculata within the First Hours of Contact

    PubMed Central

    Barbou, Annaïck; Capitaine, Carole; Bidault, Adeline; Dujon, Antoine Marie; Moraga, Dario

    2014-01-01

    Vibrio harveyi is a marine bacterial pathogen responsible for episodic epidemics generally associated with massive mortalities in many marine organisms, including the European abalone Haliotis tuberculata. The aim of this study was to identify the portal of entry and the dynamics of infection of V. harveyi in the European abalone. The results indicate that the duration of contact between V. harveyi and the European abalone influences the mortality rate and precocity. Immediately after contact, the epithelial and mucosal area situated between the gills and the hypobranchial gland was colonized by V. harveyi. Real-time PCR analyses and culture quantification of a green fluorescent protein-tagged strain of V. harveyi in abalone tissues revealed a high density of bacteria adhering to and then penetrating the whole gill-hypobranchial gland tissue after 1 h of contact. V. harveyi was also detected in the hemolymph of a significant number of European abalones after 3 h of contact. In conclusion, this article shows that a TaqMan real-time PCR assay is a powerful and useful technique for the detection of a marine pathogen such as V. harveyi in mollusk tissue and for the study of its infection dynamics. Thus, we have revealed that the adhesion and then the penetration of V. harveyi in European abalone organs begin in the first hours of contact. We also hypothesize that the portal of entry of V. harveyi in the European abalone is the area situated between the gills and the hypobranchial gland. PMID:25107972

  8. Vibrio harveyi adheres to and penetrates tissues of the European abalone Haliotis tuberculata within the first hours of contact.

    PubMed

    Cardinaud, Marion; Barbou, Annaïck; Capitaine, Carole; Bidault, Adeline; Dujon, Antoine Marie; Moraga, Dario; Paillard, Christine

    2014-10-01

    Vibrio harveyi is a marine bacterial pathogen responsible for episodic epidemics generally associated with massive mortalities in many marine organisms, including the European abalone Haliotis tuberculata. The aim of this study was to identify the portal of entry and the dynamics of infection of V. harveyi in the European abalone. The results indicate that the duration of contact between V. harveyi and the European abalone influences the mortality rate and precocity. Immediately after contact, the epithelial and mucosal area situated between the gills and the hypobranchial gland was colonized by V. harveyi. Real-time PCR analyses and culture quantification of a green fluorescent protein-tagged strain of V. harveyi in abalone tissues revealed a high density of bacteria adhering to and then penetrating the whole gill-hypobranchial gland tissue after 1 h of contact. V. harveyi was also detected in the hemolymph of a significant number of European abalones after 3 h of contact. In conclusion, this article shows that a TaqMan real-time PCR assay is a powerful and useful technique for the detection of a marine pathogen such as V. harveyi in mollusk tissue and for the study of its infection dynamics. Thus, we have revealed that the adhesion and then the penetration of V. harveyi in European abalone organs begin in the first hours of contact. We also hypothesize that the portal of entry of V. harveyi in the European abalone is the area situated between the gills and the hypobranchial gland. PMID:25107972

  9. The production of anti-Vibrio harveyi egg yolk immunoglobulin and evaluation of its stability and neutralisation efficacy

    Microsoft Academic Search

    Kawin Punyokun; Ratchanee Hongprayoon; Prapansak Srisapoome; Theerapol Sirinarumitr

    2012-01-01

    In order to replace the antibiotic treatment for control of Vibrio harveyi, a causal agent of luminous disease in Black tiger shrimp, anti-V. harveyi IgY was produced and showed its potential in our preliminary study. However, for further use as feed additive, the IgY stability should be evaluated. The titre of specific IgY was enhanced with an immunostimulant, C-phosphate guanosine

  10. Inhibition of Luminescence and Virulence in the Black Tiger Prawn (Penaeus monodon) Pathogen Vibrio harveyi by Intercellular Signal Antagonists

    Microsoft Academic Search

    MICHAEL MANEFIELD; LACHLAN HARRIS; SCOTT A. RICE; ROCKY DE NYS; STAFFAN KJELLEBERG

    2000-01-01

    Expression of luminescence in the Penaeus monodon pathogen Vibrio harveyi is regulated by an intercellular quorum sensing mechanism involving the synthesis and detection of two signaling molecules, one of which is N-hydroxy butanoyl-L-homoserine lactone and the other of which is uncharacterized. Indirect evidence has suggested that virulence, associated with a toxic extracellular protein, and luminescence in V. harveyi are coregulated.

  11. The nucleotide sequence of Beneckea harveyi 5S rRNA. [bioluminescent marine bacterium

    NASA Technical Reports Server (NTRS)

    Luehrsen, K. R.; Fox, G. E.

    1981-01-01

    The primary sequence of the 5S ribosomal RNA isolated from the free-living bioluminescent marine bacterium Beneckea harveyi is reported and discussed in regard to indications of phylogenetic relationships with the bacteria Escherichia coli and Photobacterium phosphoreum. Sequences were determined for oligonucleotide products generated by digestion with ribonuclease T1, pancreatic ribonuclease and ribonuclease T2. The presence of heterogeneity is indicated for two sites. The B. harveyi sequence can be arranged into the same four helix secondary structures as E. coli and other prokaryotic 5S rRNAs. Examination of the 5S-RNS sequences of the three bacteria indicates that B. harveyi and P. phosphoreum are specifically related and share a common ancestor which diverged from an ancestor of E. coli at a somewhat earlier time, consistent with previous studies.

  12. Recombinant ferritin protein protects Penaeus monodon infected by pathogenic Vibrio harveyi.

    PubMed

    Maiti, Biswajit; Khushiramani, Rekha; Tyagi, Anuj; Karunasagar, Iddya; Karunasagar, Indrani

    2010-01-25

    Hemocytes of shrimp perform an essential role in defense against microbial pathogens, involving both cellular and humoral factors. The gene coding for ferritin in black tiger shrimp Penaeus monodon was cloned, sequenced and expressed using pQE-30-UA vector and SG13009 Escherichia coli host cells. The deduced amino acid sequence of P. monodon ferritin showed 32 to 95% similarity with ferritin proteins of other organisms. The recombinant protein was purified by nickel-nitrilotriacetic acid affinity chromatography. A single thick band of recombinant protein of approximately 21 kDa was observed in 15% sodium dodecyl sulfate polyacrylamide gel electrophoresis. Following mild acid treatment, 2 bands of ca. 14 and 7 kDa were produced; aspartine and proline acid cleavage sites were found at amino acid residues 123-124. The purified recombinant ferritin helped in reducing the mortality in shrimp infected with Vibrio harveyi . However, no direct antimicrobial activity against pathogenic V. harveyi was observed. PMID:20225671

  13. Norepinephrine and dopamine increase motility, biofilm formation, and virulence of Vibrio harveyi

    PubMed Central

    Yang, Qian; Anh, Nguyen D. Q.; Bossier, Peter; Defoirdt, Tom

    2014-01-01

    Vibrio harveyi is one of the major pathogens of aquatic organisms, affecting both vertebrates and invertebrates, and causes important losses in the aquaculture industry. In order to develop novel methods to control disease caused by this pathogen, we need to obtain a better understanding of pathogenicity mechanisms. Sensing of catecholamines increases both growth and production of virulence-related factors in pathogens of terrestrial animals and humans. However, at this moment, knowledge on the impact of catecholamines on the virulence of pathogens of aquatic organisms is lacking. In the present study, we report that in V. harveyi, norepinephrine (NE) and dopamine (Dopa) increased growth in serum-supplemented medium, siderophore production, swimming motility, and expression of genes involved in flagellar motility, biofilm formation, and exopolysaccharide production. Consistent with this, pretreatment of V. harveyi with catecholamines prior to inoculation into the rearing water resulted in significantly decreased survival of gnotobiotic brine shrimp larvae, when compared to larvae challenged with untreated V. harveyi. Further, NE-induced effects could be neutralized by ?-adrenergic antagonists or by the bacterial catecholamine receptor antagonist LED209, but not by ?-adrenergic or dopaminergic antagonists. Dopa-induced effects could be neutralized by dopaminergic antagonists or LED209, but not by adrenergic antagonists. Together, our results indicate that catecholamine sensing increases the success of transmission of V. harveyi and that interfering with catecholamine sensing might be an interesting strategy to control vibriosis in aquaculture. We hypothesize that upon tissue and/or hemocyte damage during infection, pathogens come into contact with elevated catecholamine levels, and that this stimulates the expression of virulence factors that are required to colonize a new host. PMID:25414697

  14. The anguibactin biosynthesis and transport genes are encoded in the chromosome of Vibrio harveyi: a possible evolutionary origin for the pJM1 plasmid–encoded system of Vibrio anguillarum?

    PubMed Central

    Naka, Hiroaki; Actis, Luis A; Crosa, Jorge H

    2013-01-01

    Many Vibrio anguillarum serotype O1 strains carry 65-kb pJM1-type plasmids harboring genes involved in siderophore anguibactin biosynthesis and transport. The anguibactin system is an essential factor for V. anguillarum to survive under iron-limiting conditions, and as a consequence, it is a very important virulence factor of this bacterium. Our comparative analysis of genomic data identified a cluster harboring homologs of anguibactin biosynthesis and transport genes in the chromosome of Vibrio harveyi. We have purified the putative anguibactin siderophore and demonstrated that it is indeed anguibactin by mass spectrometry and specific bioassays. Furthermore, we characterized two genes, angR and fatA, in this chromosome cluster that, respectively, participate in anguibactin biosynthesis and transport as determined by mutagenesis analysis. Furthermore, we found that the V. harveyi FatA protein is located in the outer membrane fractions as previously demonstrated in V. anguillarum. Based on our data, we propose that the anguibactin biosynthesis and transport cluster in the V. anguillarum pJM1 plasmid have likely evolved from the chromosome cluster of V. harveyi or vice versa. PMID:23335587

  15. Discovery of a nitric oxide responsive quorum sensing circuit in Vibrio harveyi.

    PubMed

    Henares, Bernadette M; Higgins, Kate E; Boon, Elizabeth M

    2012-08-17

    Bacteria use small molecules to assess the density and identity of nearby organisms and formulate a response. This process, called quorum sensing (QS), commonly regulates bioluminescence, biofilm formation, and virulence. Vibrio harveyi have three described QS circuits. Each involves the synthesis of a molecule that regulates phosphorylation of its cognate receptor kinase. Each receptor exchanges phosphate with a common phosphorelay protein, LuxU, which ultimately regulates bioluminescence. Here, we show that another small molecule, nitric oxide (NO), participates in QS through LuxU. V. harveyi display a NO concentration-dependent increase in bioluminescence that is regulated by an hnoX gene. We demonstrate that H-NOX is a NO sensor and NO/H-NOX regulates phosphorylation of a kinase that transfers phosphate to LuxU. This study reveals the discovery of a fourth QS pathway in V. harveyi and suggests that bacteria use QS to integrate not only the density of bacteria but also other diverse information about their environment into decisions about gene expression. PMID:22606970

  16. Immunoprotective analysis of VhhP2, a Vibrio harveyi vaccine candidate.

    PubMed

    Sun, Kun; Zhang, Wei-Wei; Hou, Jin-Hui; Sun, Li

    2009-05-11

    VhhP2 is an outer membrane protein identified in a pathogenic Vibrio harveyi strain, T4, isolated from diseased fish. When used as a subunit vaccine, purified recombinant VhhP2 affords high level of protection upon Japanese flounder against V. harveyi challenge. Vaccination with VhhP2 induced the expression of a number of immune-related genes, especially those encoding immunoglobulin M (IgM) and major histocompatibility complex (MHC) IIalpha. A VhhP2 surface display system, in the form of the fish commensal strain PF3 harboring the vhhP2-expressing plasmid pJVP, was constructed. PF3/pJVP is able to produce and present recombinant VhhP2 on cell surface. Vaccination of fish with live PF3/pJVP via intraperitoneal injection elicited strong immunoprotection. Vaccination of fish orally with live PF3/pJVP embedded in alginate microspheres also induced effective immunoprotection. In addition, a VhhP2-based surface display system was created, in which VhhP2 serves as a carrier for the surface delivery of a heterologous Edwardsiella tarda immunogen, Et18, that is fused in-frame to VhhP2. DH5alpha/pJVP18, which expresses and surface-displays the VhhP2-Et18 chimera, proved to be an effective vaccine that can protect fish against infections by V. harveyi and E. tarda to the extents comparable to those produced by vaccination with purified recombinant VhhP2 and Et18, respectively. These data suggest that VhhP2 may be applied as a vaccine and a vaccine carrier against infections by V. harveyi and other pathogens such as E. tarda. PMID:19428886

  17. Nitric oxide as an antimicrobial molecule against Vibrio harveyi infection in the hepatopancreas of Pacific white shrimp, Litopenaeus vannamei.

    PubMed

    Chen, Ting; Wong, Nai-Kei; Jiang, Xiao; Luo, Xing; Zhang, Lvping; Yang, Dan; Ren, Chunhua; Hu, Chaoqun

    2015-01-01

    Nitric oxide (NO) is a key effector molecule produced in the innate immune systems of many species for antimicrobial defense. However, how NO production is regulated during bacterial infection in invertebrates, especially crustaceans, remains poorly understood. Vibrio harveyi, a Gram-negative marine pathogen, is among the most prevalent and serious threats to the world's shrimp culture industry. Its virulence typically manifests itself through shrimp hepatopancreas destruction. In the current study, we found that NO generated by an in vitro donor system (NOC-18) could rapidly and effectively kill V. harveyi. In addition, injection of heat-killed V. harveyi increased the concentration of NO/nitrite and the mRNA expression of nitric oxide synthase (NOS) in the hepatopancreas of Pacific white shrimp (Litopenaeus vannamei), the commercially most significant shrimp species. Live V. harveyi challenge also induced NO/nitrite production and NOS gene expression in primary L. vannamei hepatopancreatic cells in a time- and dose-dependent manner. Co-incubation of l-NAME, an inhibitor selective for mammalian constitutive NOSs, dose-dependently blocked V. harveyi-induced NO/nitrite production, without affecting V. harveyi-induced NOS mRNA expression. Furthermore, l-NAME treatment significantly increased the survival rate of infecting V. harveyi in cultured primary hepatopancreatic cells of L. vannamei. As a whole, we have demonstrated that endogenous NO produced by L. vannamei hepatopancreatic cells occurs in enzymatically regulated manners and is sufficient to act as a bactericidal molecule for V. harveyi clearance. PMID:25449376

  18. Identification and characterization of Vibrio harveyi associated with diseased abalone Haliotis diversicolor.

    PubMed

    Jiang, Qingru; Shi, Liuyang; Ke, Caihuan; You, Weiwei; Zhao, Jing

    2013-03-26

    Mass mortality of farmed small abalone Haliotis diversicolor occurred in Fujian, China, from 2009 to 2011. Among isolates obtained from moribund abalones, the dominant species AP37 exhibited the strongest virulence. After immersion challenge with 106 CFU ml-1 of AP37, abalone mortalities of 0, 53 and 67% were induced at water temperatures of 20°C, 24°C, and 28°C, respectively. Following intramuscular injection, AP37 showed a low LD50 (median lethal concentration) value of 2.9 × 102 CFU g-1 (colony forming units per gram abalone wet body weight). The LT50 (median lethal time) values were 5.2 h for 1 × 106 CFU abalone-1, 8.4 h for 1 × 105 CFU abalone-1, and 21.5 h for 1 × 104 CFU abalone-1. For further analysis of virulence, AP37 was screened for the production of extracellular factors. The results showed that various factors including presence of flagella and production of extracellular enzymes, such as lipase, phospholipase and haemolysin, could be responsible for pathogenesis. Based on its 16S rRNA gene sequence, strain AP37 showed >98.8% similarity to Vibrio harveyi, V. campbellii, V. parahaemolyticus, V. alginolyticus, V. natriegens and V. rotiferianus, so it could not be identified by this method. However, multi-locus sequence analysis (MLSA) of concatenated sequences, including the rpoD, rctB, gyrB, toxR and pyrH genes, identified strain AP37 as V. harveyi. Phenotypic characters of AP37 were identified by API 20E. In antibiotic susceptibility tests, strain AP37 exhibited susceptibility to 7 antibiotics and resistance to 13. This is the first report of a V. harveyi-related species being linked with the mass mortality of adult abalone H. diversicolor in southern China. PMID:23548363

  19. Proteomic analysis of protein expression in the induction of the viable but Nonculturable State of Vibrio harveyi SF1.

    PubMed

    Jia, Juntao; Li, Zhengyi; Cao, Jijuan; Jiang, Yinghui; Liang, Chengzhu; Liu, Mengzhen

    2013-10-01

    Vibrio harveyi has been reported to enter into a viable but nonculturable (VBNC) state. One marine V. harveyi strain, SF1 became nonculturable when incubated in seawater microcosm at 4 °C within 60 days. We investigated protein expression in the exponential phase of V. harveyi SF1 and compared it to the VBNC state. Cytosolic proteins were resolved by two-dimensional polyacrylamide gel electrophoresis using pH 4-7 linear gradients. Among these proteins, sixteen proteins which were strongly downregulated or upregulated in the VBNC cells were identified by MALDI-TOF-TOF mass spectrometry. The results indicated that the differentially expressed proteins were mainly focused on stress response proteins and key components of central and intermediary metabolism, like carbohydrate metabolism, transport, and translation. This study provided clues for understanding the mechanism of adaptation to the VBNC state. PMID:23689940

  20. Metabolomic analysis revealed the differential responses in two pedigrees of clam Ruditapes philippinarum towards Vibrio harveyi challenge.

    PubMed

    Liu, Xiaoli; Zhao, Jianmin; Wu, Huifeng; Wang, Qing

    2013-12-01

    Manila clam Ruditapes philippinarum is an important marine aquaculture shellfish. This species has several pedigrees including White, Zebra, Liangdao Red and Marine Red distributing in the coastal areas in North China. In this work, we studied the metabolic differences induced by Vibrio harveyi in hepatopancreas from White and Zebra clams using NMR-based metabolomics. Metabolic responses (e.g., amino acids, glucose, glycogen, ATP and succinate) and altered mRNA expression levels of related genes (ATP synthase, heat shock protein 90, defensin and lysozyme) suggested that V. harveyi induced clear disruption in energy metabolism and immune stresses in both White and Zebra clam hepatopancreas. However, V. harveyi caused obvious osmotic stress in Zebra clam hepatopancreas, which was not observed in V. harveyi-challenged White clams samples. In addition, V. harveyi challenge induced more severe disruption in energy metabolism and immune stress in White clams than in Zebra clams. Overall, our results indicated that the biological differences between different pedigrees of R. philippinarum should be considered in immunity studies. PMID:24161758

  1. Severe Wound Infection with Photobacterium damselae ssp. damselae and Vibrio harveyi, following a Laceration Injury in Marine Environment: A Case Report and Review of the Literature

    PubMed Central

    Hundenborn, Jörg; Thurig, Steffi

    2013-01-01

    Marine microorganisms are uncommon etiologies of skin and skin structure infections, that is, wound infections. We report a case of severe wound infection, caused by the marine Photobacterium damselae (Vibrionaceae), in a 64-year-old male patient, returning from Australia. The isolate tested positive for pPHDD1, a plasmid conferring high-level virulence. Furthermore, the wound was coinfected with Vibrio harveyi, a halophile bacterium, which has never been reported from human infections before. Identification was achieved by use of Matrix-Assisted Laser Desorption-Ionization Time of Flight Mass Spectrometry (MALDI-TOF) and confirmed by 16S rDNA sequencing. Data retrieval from bibliography was complicated since P. damselae has been renamed often with a number of synonyms present in the literature: Photobacterium damsela, Vibrio damselae, Vibrio damsela, Pasteurella damselae, and Listonella damsela. With all synonyms used as query terms, a literature search provided less than 20 cases published worldwide. A majority of those cases presenting as severe wound infection are even fatal following progression into necrotizing fasciitis. Management with daily wound dressing and antibiotic therapy (ofloxacin empirically, followed by doxycycline after availability of microbiology) led in the reported case to a favorable outcome, which seems to be, however, the exception based on a review of the available literature. PMID:24171004

  2. Contrasting Inter- and Intraspecies Recombination Patterns in the “Harveyi Clade” Vibrio Collected over Large Spatial and Temporal Scales

    PubMed Central

    Urbanczyk, Henryk; Ogura, Yoshitoshi; Hayashi, Tetsuya

    2015-01-01

    Recombination plays an important role in the divergence of bacteria, but the frequency of interspecies and intraspecies recombination events remains poorly understood. We investigated recombination events that occurred within core genomes of 35 Vibrio strains (family Vibrionaceae, Gammaproteobacteria), from six closely related species in the so-called “Harveyi clade.” The strains were selected from a collection of strains isolated in the last 90 years, from various environments worldwide. We found a close relationship between the number of interspecies recombination events within core genomes of the 35 strains and the overall genomic identity, as inferred from calculations of the average nucleotide identity. The relationship between the overall nucleotide identity and the number of detected interspecies recombination events was comparable when analyzing strains isolated over 80 years apart, from different hemispheres, or from different ecologies, as well as in strains isolated from the same geographic location within a short time frame. We further applied the same method of detecting recombination events to analyze 11 strains of Vibrio campbellii, and identified disproportionally high number of intraspecies recombination events within the core genomes of some, but not all, strains. The high number of recombination events was detected between V. campbellii strains that have significant temporal (over 18 years) and geographical (over 10,000 km) differences in their origins of isolation. Results of this study reveal a remarkable stability of Harveyi clade species, and give clues about the origins and persistence of species in the clade. PMID:25527835

  3. Sigma E Regulators Control Hemolytic Activity and Virulence in a Shrimp Pathogenic Vibrio harveyi

    E-print Network

    Rattanama, Pimonsri

    Members of the genus Vibrio are important marine and aquaculture pathogens. Hemolytic activity has been identified as a virulence factor in many pathogenic vibrios including V. cholerae, V. parahaemolyticus, V. alginolyticus, ...

  4. RNAi knock-down of the Litopenaeus vannamei Toll gene ( LvToll) significantly increases mortality and reduces bacterial clearance after challenge with Vibrio harveyi

    Microsoft Academic Search

    KC Han-Ching Wang; Chun-Wei Tseng; Han-You Lin; I-Tung Chen; Ya-Hui Chen; Yi-Min Chen; Tzong-Yueh Chen; Huey-Lang Yang

    2010-01-01

    In this study, we used real-time PCR to simultaneously monitor the responses of 12 key genes of the shrimp innate immune system in Litopenaeus vannamei after challenge with Vibrio harveyi. In the proPO activating system, we found that proPO was up-regulated (3.3× control at 36hpi). The hemolymph clotting genes transglutaminase (TGase) and clotting protein were also up-regulated, as were 5

  5. Studies on the immunomodulatory effect of polysaccharide gel extracted from Durio zibethinus in Penaeus monodon shrimp against Vibrio harveyi and WSSV.

    PubMed

    Pholdaeng, Komsil; Pongsamart, Sunanta

    2010-04-01

    Oral administration of polysaccharide gel (PG) in shrimp diets revealed immunostimulating potential and disease resistance in Penaeus monodon (black tiger shrimp). PG from the fruit-rind of Durio zibethinus has been characterized to be a pectic polysaccharide with immunomodulating and antibacterial activities. PG inhibited growth of the shrimp bacterial pathogen, Vibrio harveyi 1526, by agar diffusion and broth microdilution tests. Clear inhibition zones on agar plates were observed at the lowest PG concentration of 3.1 mg/ml, where minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for PG were 6.3 and 12.5 mg/ml, respectively. Each group of juvenile shrimps, initial mean body weight 0.29 +/- 0.04 g, was housed in a closed-recirculating treated water system and was fed with PG-supplemented diets containing 1, 2 and 3% PG or shrimp basal diet in the control group for 8 and 12 weeks. PG-supplemented diets did not contribute to the overall growth of black tiger shrimp. The immune response was evaluated by analysis of prophenoloxidase activity and total hemocyte count in the shrimp fed PG-supplemented diets for 12 weeks. Prophenoloxidase activity in shrimp fed the 1, 2 and 3% PG-supplemented diet and total hemocyte count in shrimp fed the 1 and 2% PG-supplemented diet were higher (P < 0.05) than those of the control group. The percent survival was higher in groups fed the 1-3% PG-supplemented diets in challenge tests with either white spot syndrome virus (WSSV) or the bacterium V. harveyi 1526 than that of the control group. Relative percent survival (RPS) values in groups fed the 2% PG-supplemented diet showed the highest RPS value for disease resistance of 100% (at Day 6) and 36% (at Day 4) in treated shrimp against viral and bacterial infection, respectively. Mortality of PG-supplemented diets in treated shrimps against WSSV infection was also found to be much lower (P < 0.05) than that of the control group. PMID:20034573

  6. Deducing receptor signaling parameters from in vivo analysis: LuxN/AI-1 quorum sensing in Vibrio harveyi

    PubMed Central

    Swem, Lee R.; Swem, Danielle L.; Wingreen, Ned S.; Bassler, Bonnie L.

    2008-01-01

    Summary Quorum sensing, a process of bacterial cell-cell communication, relies on production, detection, and response to autoinducer signaling molecules. Here we focus on LuxN, a nine transmembrane domain protein from Vibrio harveyi, and the founding example of membrane-bound receptors for acyl-homoserine lactone (AHL) autoinducers. Previously, nothing was known about signal recognition by membrane-bound AHL receptors. We used mutagenesis and suppressor analyses to identify the AHL-binding domain of LuxN, and discovered LuxN mutants that confer decreased and increased AHL sensitivity. Our analysis of dose-response curves of multiple LuxN mutants pins these inverse phenotypes on quantifiable opposing shifts in the free-energy bias of LuxN for its kinase and phosphatase states. To extract signaling parameters, we exploited a strong LuxN antagonist, one of fifteen small-molecule antagonists we identified. We find that quorum-sensing-mediated communication can be manipulated positively and negatively to control bacterial behavior, and that signaling parameters can be deduced from in vivo data. PMID:18692469

  7. Gene silencing of a prophenoloxidase activating enzyme in the shrimp, Penaeus monodon, increases susceptibility to Vibrio harveyi infection.

    PubMed

    Charoensapsri, Walaiporn; Amparyup, Piti; Hirono, Ikuo; Aoki, Takashi; Tassanakajon, Anchalee

    2009-07-01

    The prophenoloxidase (proPO) activating system is an important innate immune response against microbial infections in invertebrates. The major enzyme, phenoloxidase (PO), is synthesized as an inactive precursor and its activation to an active enzyme is mediated by a cascade of clip domain serine proteinases (clip-SPs). In this study, a cDNA encoding a proPO activating enzyme (PPAE) from the black tiger shrimp, Penaeus monodon, designated as PmPPAE1, was cloned and characterized. The full-length cDNA contains an open reading frame (ORF) of 1392bp encoding a predicted protein of 463 amino acids including an 18 amino acid signal peptide. The PmPPAE1 protein exhibits a characteristic sequence structure of clip-SPs consisting of the clip domain at the N-terminus and a SP domain at the C-terminus. Sequence analysis showed that PmPPAE1 exhibited the highest amino acid sequence similarity (70%) to a PPAE of the crayfish, Pacifastacus leniusculus. PmPPAE1 mRNA is abundantly expressed in hemocytes, and this is regulated after systemic Vibrio harveyi infection supporting that it is an immune-responsive gene. RNA interference-mediated suppression of PmPPAE1, performed by injection of double-stranded RNA (dsRNA) corresponding to the PmPPAE1 gene into shrimp, resulted in a significant reduction of PmPPAE1 but not other clip-SP and related gene transcript levels of P. monodon, suggesting gene-specific knockdown. RNAi-mediated silencing of PmPPAE1 gene significantly decreased the total PO activity (36.7%) in shrimp and additionally increased the mortality of V. harveyi infected shrimp, the latter of which correlated with an increase in the number of viable bacteria in the hemolymph. These results indicate that PmPPAE1 functions in the proPO system and is an important component in the shrimp immune system. PMID:19428482

  8. Intracellular generation of superoxide as a by-product of Vibrio harveyi luciferase expressed in Escherichia coli.

    PubMed

    González-Flecha, B; Demple, B

    1994-04-01

    Luciferase genes are widely used as reporters of gene expression because of the high sensitivity of chemiluminescence detection and the possibility of monitoring light production in intact cells. We engineered fusions of the Escherichia coli soxS promoter to the luciferase structural genes (luxAB) from Vibrio harveyi. Since soxS transcription is positively triggered by the activated SoxR protein in response to agents such as paraquat that generate intracellular superoxide, we hoped to use this construct as a sensitive reporter of redox stress agents. Although a soxR+ soxS'::luxAB fusion exhibited a paraquat-inducible synthesis of luciferase, a smaller increase was consistently observed even in the absence of known soxRS inducers. This endogenous induction was soxR dependent and was further characterized by introducing a plasmid carrying the luciferase structural genes without the soxS promoter into a strain carrying a soxS'::lacZ fusion in the bacterial chromosome. These cells exhibited increased beta-galactosidase expression as they grew into mid-log phase. This increase was ascribed to luciferase activity because beta-galactosidase induction was suppressed (but not eliminated) when the substrate n-decanal was present in the medium. The soxS'::luxAB plasmid transformed superoxide dismutase-deficient strains very poorly under aerobic conditions but just as efficiently as a control plasmid under anaerobic conditions. The production of hydrogen peroxide, the dismutation product of superoxide anion, was significantly increased in strains carrying bacterial luciferase and maximal in the absence of n-decanal. Taken collectively, these data point to the generation of significant amounts of intracellular superoxide by bacterial luciferase, the possible mechanism of which is discussed. In addition to providing insights into the role of superoxide in the activation of the SoxR protein, these results suggest caution in the interpretation of experiments using luciferase as a reporter of gene expression. PMID:8157597

  9. Mutation of Bacterium Vibrio gazogenes for Selective Preparation of Colorants Farzaneh Alihosseini

    E-print Network

    Hammock, Bruce D.

    Mutation of Bacterium Vibrio gazogenes for Selective Preparation of Colorants Farzaneh Alihosseini nitrosoguanidine was used as a mutation agent to increase the genetic diversity and the production yield of the bacteria of the family of Vibrio gazo- genes. The analysis of the mutated samples showed that two new main

  10. Structure of the beta 2 homodimer of bacterial luciferase from Vibrio harveyi: X-ray analysis of a kinetic protein folding trap.

    PubMed Central

    Thoden, J. B.; Holden, H. M.; Fisher, A. J.; Sinclair, J. F.; Wesenberg, G.; Baldwin, T. O.; Rayment, I.

    1997-01-01

    Luciferase, as isolated from Vibrio harveyi, is an alpha beta heterodimer. When allowed to fold in the absence of the alpha subunit, either in vitro or in vivo, the beta subunit of enzyme will form a kinetically stable homodimer that does not unfold even after prolonged incubation in 5 M urea at pH 7.0 and 18 degrees C. This form of the beta subunit, arising via kinetic partitioning on the folding pathway, appears to constitute a kinetically trapped alternative to the heterodimeric enzyme (Sinclair JF, Ziegler MM, Baldwin TO. 1994. Kinetic partitioning during protein folding yields multiple native states. Nature Struct Biol 1: 320-326). Here we describe the X-ray crystal structure of the beta 2 homodimer of luciferase from V. harveyi determined and refined at 1.95 A resolution. Crystals employed in the investigational belonged to the orthorhombic space group P2(1)2(1)2(1) with unit cell dimensions of a = 58.8 A, b = 62.0 A, and c = 218.2 A and contained one dimer per asymmetric unit. Like that observed in the functional luciferase alpha beta heterodimer, the major tertiary structural motif of each beta subunit consists of an (alpha/beta)8 barrel (Fisher AJ, Raushel FM, Baldwin TO, Rayment I. 1995. Three-dimensional structure of bacterial luciferase from Vibrio harveyi at 2.4 A resolution. Biochemistry 34: 6581-6586). The root-mean-square deviation of the alpha-carbon coordinates between the beta subunits of the hetero- and homodimers is 0.7 A. This high resolution X-ray analysis demonstrated that "domain" or "loop" swapping has not occurred upon formation of the beta 2 homodimer and thus the stability of the beta 2 species to denaturation cannot be explained in such simple terms. In fact, the subunit:subunit interfaces observed in both the beta 2 homodimer and alpha beta heterodimer are remarkably similar in hydrogen-bonding patterns and buried surface areas. PMID:9007973

  11. Identification and analysis of an intracellular Cu/Zn superoxide dismutase from Sepiella maindroni under stress of Vibrio harveyi and Cd2+.

    PubMed

    He, Jian-yu; Chi, Chang-feng; Liu, Hui-hui

    2014-11-01

    Superoxide dismutases (SODs) are ubiquitous family of metalloenzymes involved in protecting organisms from excess reactive oxygen species damage. In this paper, a novel intracellular Cu/ZnSOD from Sepiella maindroni (designated as SmSOD) was identified and characterized. The full-length cDNA sequence of SmSOD (GenBank accession No. KF908850) was 709 bp containing an open reading frame (ORF) of 459 bp, encoding 153 amino acid residues peptide with predicted pI/MW (6.02/15.75 kDa), a 131 bp-5'- and 116 bp-3'- untranslated region (UTR). BLASTn analysis and phylogenetic relationship strongly suggested that the sequence shared high similarity with known Cu/Zn SODs. Several highly conserved motifs, including two typical Cu/Zn SOD family domains, two conserved Cu-/Zn-binding sites (H-47, H-49, H-64, H-120 for Cu binding, and H-64, H-72, H-81, D-84 for Zn binding) and intracellular disulfide bond (C-58 and C-146), were also identified in SmSOD. Time-dependent mRNA expression of SmSOD in hepatopancreas was recorded by quantitative real-time RT-PCR after Vibrio harveyi injection and Cd(2+) exposure. The results indicated that SmSOD was an acute-phase protein involved in the immune responses against pathogens and biological indicator for metal contaminants in aquatic environment. PMID:24975083

  12. Complete genome sequence of Vibrio fischeri: A symbiotic bacterium with pathogenic congeners

    E-print Network

    Dunn, Anne K.

    mechanisms by which V. fischeri and other symbiotic bacteria adjust to the special environment of hostComplete genome sequence of Vibrio fischeri: A symbiotic bacterium with pathogenic congeners E. G-associated bacteria in a number of genera (2). The Vibrionaceae comprise several dozen species that are often found

  13. Luminescence Control in the Marine Bacterium Vibrio fischeri: An Analysis of the Dynamics of

    E-print Network

    Sontag, Eduardo

    Luminescence Control in the Marine Bacterium Vibrio fischeri: An Analysis of the Dynamics of lux of transcriptional regula- tors is used by a wide variety of bacteria to regulate the expression of certain genes light organ (Sitnikov et al., 1995). Several bac- terial species contain lux-type transcriptional regu

  14. Structural and Functional Investigation of Flavin Binding Center of the NqrC Subunit of Sodium-Translocating NADH:Quinone Oxidoreductase from Vibrio harveyi.

    PubMed

    Borshchevskiy, Valentin; Round, Ekaterina; Bertsova, Yulia; Polovinkin, Vitaly; Gushchin, Ivan; Ishchenko, Andrii; Kovalev, Kirill; Mishin, Alexey; Kachalova, Galina; Popov, Alexander; Bogachev, Alexander; Gordeliy, Valentin

    2015-01-01

    Na+-translocating NADH:quinone oxidoreductase (NQR) is a redox-driven sodium pump operating in the respiratory chain of various bacteria, including pathogenic species. The enzyme has a unique set of redox active prosthetic groups, which includes two covalently bound flavin mononucleotide (FMN) residues attached to threonine residues in subunits NqrB and NqrC. The reason of FMN covalent bonding in the subunits has not been established yet. In the current work, binding of free FMN to the apo-form of NqrC from Vibrio harveyi was studied showing very low affinity of NqrC to FMN in the absence of its covalent bonding. To study structural aspects of flavin binding in NqrC, its holo-form was crystallized and its 3D structure was solved at 1.56 Å resolution. It was found that the isoalloxazine moiety of the FMN residue is buried in a hydrophobic cavity and that its pyrimidine ring is squeezed between hydrophobic amino acid residues while its benzene ring is extended from the protein surroundings. This structure of the flavin-binding pocket appears to provide flexibility of the benzene ring, which can help the FMN residue to take the bended conformation and thus to stabilize the one-electron reduced form of the prosthetic group. These properties may also lead to relatively weak noncovalent binding of the flavin. This fact along with periplasmic location of the FMN-binding domains in the vast majority of NqrC-like proteins may explain the necessity of the covalent bonding of this prosthetic group to prevent its loss to the external medium. PMID:25734798

  15. Structural and Functional Investigation of Flavin Binding Center of the NqrC Subunit of Sodium-Translocating NADH:Quinone Oxidoreductase from Vibrio harveyi

    PubMed Central

    Bertsova, Yulia; Polovinkin, Vitaly; Gushchin, Ivan; Ishchenko, Andrii; Kovalev, Kirill; Mishin, Alexey; Kachalova, Galina; Popov, Alexander; Bogachev, Alexander; Gordeliy, Valentin

    2015-01-01

    Na+-translocating NADH:quinone oxidoreductase (NQR) is a redox-driven sodium pump operating in the respiratory chain of various bacteria, including pathogenic species. The enzyme has a unique set of redox active prosthetic groups, which includes two covalently bound flavin mononucleotide (FMN) residues attached to threonine residues in subunits NqrB and NqrC. The reason of FMN covalent bonding in the subunits has not been established yet. In the current work, binding of free FMN to the apo-form of NqrC from Vibrio harveyi was studied showing very low affinity of NqrC to FMN in the absence of its covalent bonding. To study structural aspects of flavin binding in NqrC, its holo-form was crystallized and its 3D structure was solved at 1.56 Å resolution. It was found that the isoalloxazine moiety of the FMN residue is buried in a hydrophobic cavity and that its pyrimidine ring is squeezed between hydrophobic amino acid residues while its benzene ring is extended from the protein surroundings. This structure of the flavin-binding pocket appears to provide flexibility of the benzene ring, which can help the FMN residue to take the bended conformation and thus to stabilize the one-electron reduced form of the prosthetic group. These properties may also lead to relatively weak noncovalent binding of the flavin. This fact along with periplasmic location of the FMN-binding domains in the vast majority of NqrC-like proteins may explain the necessity of the covalent bonding of this prosthetic group to prevent its loss to the external medium. PMID:25734798

  16. Penetration of the Coral-Bleaching Bacterium Vibrio shiloi into Oculina patagonica

    Microsoft Academic Search

    E. Banin; T. Israely; A. Kushmaro; Y. Loya; E. Orr; E. Rosenberg

    2000-01-01

    Inoculation of the coral-bleaching bacterium Vibrio shiloi into seawater containing its host Oculina patagonica led to adhesion of the bacteria to the coral surface via a b-D-galactose receptor, followed by penetration of the bacteria into the coral tissue. The internalized V. shiloi cells were observed inside the exodermal layer of the coral by electron microscopy and fluorescence microscopy using specific

  17. Acute toxicity evaluation of explosive wastewater by bacterial bioluminescence assays using a freshwater luminescent bacterium, Vibrio qinghaiensis sp. Nov

    Microsoft Academic Search

    Zhengfang Ye; Quanlin Zhao; Mohe Zhang; Yuchen Gao

    2011-01-01

    The compositions of explosive wastewater generated from TNT (2,4,6-trinitrotoluene) purification stage were characterized by using UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), high performance liquid chromatograph (HPLC) and gas chromatograph\\/mass spectroscopy (GC\\/MS). The acute toxicity was evaluated by bacterium bioluminescence assay using a freshwater luminescent bacterium (Vibrio qinghaiensis sp. Nov.) and a marine luminescent bacterium (Photobacterium phosphoreum). The results showed

  18. DNA cloning, characterization, and inhibition studies of an ?-carbonic anhydrase from the pathogenic bacterium Vibrio cholerae.

    PubMed

    Del Prete, Sonia; Isik, Semra; Vullo, Daniela; De Luca, Viviana; Carginale, Vincenzo; Scozzafava, Andrea; Supuran, Claudiu T; Capasso, Clemente

    2012-12-13

    We have cloned, purified, and characterized an ?-carbonic anhydrase (CA, EC 4.2.1.1) from the human pathogenic bacterium Vibrio cholerae, VchCA. The new enzyme has significant catalytic activity, and an inhibition study with sulfonamides and sulfamates led to the detection of a large number of low nanomolar inhibitors, among which are methazolamide, acetazolamide, ethoxzolamide, dorzolamide, brinzolamide, benzolamide, and indisulam (KI values in the range 0.69-8.1 nM). As bicarbonate is a virulence factor of this bacterium and since ethoxzolamide was shown to inhibit the in vivo virulence, we propose that VchCA may be a target for antibiotic development, exploiting a mechanism of action rarely considered until now. PMID:23181552

  19. Vibrio panuliri sp. nov., a marine bacterium isolated from spiny lobster, Panulirus penicillatus and transfer of Vibrio ponticus from Scophthalmi clade to the newly proposed Ponticus clade.

    PubMed

    Kumari, Prabla; Poddar, Abhijit; Schumann, Peter; Das, Subrata K

    2014-12-01

    A novel marine bacterium, strain LBS2(T) was isolated from eggs carried on pleopods of the spiny lobster collected from Andaman Sea. Heterotrophic growth occurred at 1-7% NaCl. 16S rRNA gene sequence similarity revealed the strain LBS2(T) belonged to the genus Vibrio and showed above 97% similarity with eight type strains of the genus Vibrio. Multilocus analysis based on ftsZ, gapA, gyrB, mreB, pyrH recA, rpoA, and topA revealed LBS2(T) formed a separate cluster with Vibrio ponticus DSM 16217(T) with 89.8% multilocus gene sequence similarity. However, strain LBS2(T) is distantly related with other members of the Scophthalmi clade in terms of 16S rRNA signatures, phenotypic variations and multilocus gene sequence similarity, for which we propose LBS2(T) belongs to a new clade i.e. Ponticus clade with V. ponticus DSM 16217(T) as the representative type strain of the clade. DNA-DNA homologies between strain LBS2(T) and closely related strains were well below 70%. DNA G + C content was 45.3 mol%. On the basis of our polyphasic study, strain LBS2(T) represents a novel species of the genus Vibrio, for which the name Vibrio panuliri sp. nov. is proposed. The type strain is LBS2(T) (= JCM 19500(T) = DSM 27724(T) = LMG 27902(T)). PMID:25445014

  20. Triose-phosphate isomerase (TIM) of the psychrophilic bacterium Vibrio marinus. Kinetic and structural properties.

    PubMed

    Alvarez, M; Zeelen, J P; Mainfroid, V; Rentier-Delrue, F; Martial, J A; Wyns, L; Wierenga, R K; Maes, D

    1998-01-23

    The purification and characterization of triose-phosphate isomerase from the psychrophilic bacterium Vibrio marinus (vTIM) is described. Crystal structures of the vTIM-sulfate complex and the vTIM-2-phosphoglycolate complex (at a 2.7-A resolution) are also presented. The optimal growth temperature of Vibrio marinus is 15 degrees C. Stability studies show that vTIM is an unstable protein with a half-life of only 10 min at 25 degrees C. The vTIM sequence is most closely related to the sequence of Escherichia coli TIM (eTIM) (66% identity), and several unique structural features described for eTIM are also seen in vTIM, but eTIM is considerably more stable. The Td values of vTIM and eTIM, determined by calorimetric studies, are 41 and 54 degrees C, respectively. Amino acid sequence comparison reveals that vTIM has an alanine in loop 8 (at position 238), whereas all other TIM sequences known to date have a serine. The vTIM mutant A238S was produced and characterized. Compared with wild type, the catalytic efficiency of the A238S mutant is somewhat reduced, and its stability is considerably increased. PMID:9442062

  1. Hepcidin-induced hypoferremia is a critical host defense mechanism against the siderophilic bacterium Vibrio vulnificus.

    PubMed

    Arezes, João; Jung, Grace; Gabayan, Victoria; Valore, Erika; Ruchala, Piotr; Gulig, Paul A; Ganz, Tomas; Nemeth, Elizabeta; Bulut, Yonca

    2015-01-14

    Hereditary hemochromatosis, an iron overload disease caused by a deficiency in the iron-regulatory hormone hepcidin, is associated with lethal infections by siderophilic bacteria. To elucidate the mechanisms of this susceptibility, we infected wild-type and hepcidin-deficient mice with the siderophilic bacterium Vibrio vulnificus and found that hepcidin deficiency results in increased bacteremia and decreased survival of infected mice, which can be partially ameliorated by dietary iron depletion. Additionally, timely administration of hepcidin agonists to hepcidin-deficient mice induces hypoferremia that decreases bacterial loads and rescues these mice from death, regardless of initial iron levels. Studies of Vibrio vulnificus growth ex vivo show that high iron sera from hepcidin-deficient mice support extraordinarily rapid bacterial growth and that this is inhibited in hypoferremic sera. Our findings demonstrate that hepcidin-mediated hypoferremia is a host defense mechanism against siderophilic pathogens and suggest that hepcidin agonists may improve infection outcomes in patients with hereditary hemochromatosis or thalassemia. PMID:25590758

  2. Purification and Characterization of a Catalase from the Facultatively Psychrophilic Bacterium Vibrio rumoiensis S-1T Exhibiting High Catalase Activity

    Microsoft Academic Search

    ISAO YUMOTO; DAISEN ICHIHASHI; HIDEAKI IWATA; ANITA ISTOKOVICS; NOBUTOSHI ICHISE; HIDETOSHI MATSUYAMA; HIDETOSHI OKUYAMA; KOSEI KAWASAKI

    2000-01-01

    Catalase from the facultatively psychrophilic bacterium Vibrio rumoiensis S-1 T , which was isolated from an environment exposed to H2O2 and exhibited high catalase activity, was purified and characterized, and its localization in the cell was determined. Its molecular mass was 230 kDa, and the molecule consisted of four identical subunits. The enzyme, which was not apparently reduced by dithionite,

  3. Genes encoding two isocitrate dehydrogenase isozymes of a psychrophilic bacterium, Vibrio sp. strain ABE-1.

    PubMed Central

    Ishii, A; Suzuki, M; Sahara, T; Takada, Y; Sasaki, S; Fukunaga, N

    1993-01-01

    The genes coding for two structurally different isocitrate dehydrogenase isozymes (IDH-I and IDH-II) of a psychrophilic bacterium, Vibrio sp. strain ABE-1, were cloned and sequenced. Open reading frames of the genes (icdI and icdII) are 1,248 and 2,229 bp in length, respectively. The amino acid sequences predicted from the open reading frames of icdI and icdII corresponded to the N-terminal amino acid sequences of the purified IDH-I and IDH-II, respectively. No homology was found between the deduced amino acid sequences of the isozymes; however, the IDH-I, a dimeric enzyme, had a high amino acid sequence identity (74.3%) to the Escherichia coli IDH. The deduced amino acid sequence of the IDH-II, a monomeric enzyme, was not related to any known sequence. However, the IDH-II had an amino acid sequence homologous to that of a cyanogen bromide-cleaved peptide containing a putative active-site methionyl residue of the monomeric IDH of Azotobacter vinelandii. The two genes (icdlI and icdII) were found to be tandemly located in the same orientation. Northern (RNA) blot analyses showed that the two genes are transcribed independently. Primer extension experiments located single transcriptional start sites 39 and 96 bp upstream of the start codons of icdI and icdII, respectively. The amount of icdI transcript but not icdII increased when Vibrio sp. strain ABE-1 cells were cultured in acetate minimal medium. Images PMID:8226630

  4. Secondary Metabolites Produced by the Marine Bacterium Halobacillus salinus That Inhibit Quorum Sensing-Controlled Phenotypes in Gram-Negative Bacteria

    Microsoft Academic Search

    Margaret E. Teasdale; Jiayuan Liu; Joselynn Wallace; Fatemeh Akhlaghi; David C. Rowley

    2009-01-01

    Certain bacteria use cell-to-cell chemical communication to coordinate community-wide phenotypic expres- sion, including swarming motility, antibiotic biosynthesis, and biofilm production. Here we present a marine gram-positive bacterium that secretes secondary metabolites capable of quenching quorum sensing-controlled behaviors in several gram-negative reporter strains. Isolate C42, a Halobacillus salinus strain obtained from a sea grass sample, inhibits bioluminescence production by Vibrio harveyi

  5. Administration of Bacillus subtilis strains in the rearing water enhances the water quality, growth performance, immune response, and resistance against Vibrio harveyi infection in juvenile white shrimp, Litopenaeus vannamei.

    PubMed

    Zokaeifar, Hadi; Babaei, Nahid; Saad, Che Roos; Kamarudin, Mohd Salleh; Sijam, Kamaruzaman; Balcazar, Jose Luis

    2014-01-01

    In this study, vegetative cell suspensions of two Bacillus subtilis strains, L10 and G1 in equal proportions, was administered at two different doses 10(5) (BM5) and 10(8) (BM8) CFU ml(-1) in the rearing water of shrimp (Litopenaeus vannamei) for eight weeks. Both probiotic groups showed a significant reduction of ammonia, nitrite and nitrate ions under in vitro and in vivo conditions. In comparison to untreated control group, final weight, weight gain, specific growth rate (SGR), food conversion ratio (FCR) and digestive enzymatic activity were significantly greater in the BM5 and BM8 groups. Significant differences for survival were recorded in the BM8 group as compared to the control. Eight weeks after the start of experiment, shrimp were challenged with Vibrio harveyi. Statistical analysis revealed significant differences in shrimp survival between probiotic and control groups. Cumulative mortality of the control group was 80%, whereas cumulative mortality of the shrimp that had been given probiotics was 36.7% with MB8 and 50% with MB5. Subsequently, real-time RT-PCR was employed to determine the mRNA levels of prophenoloxidase (proPO), peroxinectin (PE), lipopolysaccharide- and ?-1,3-glucan- binding protein (LGBP) and serine protein (SP). The expression of all immune-related genes studied was only significantly up-regulated in the BM5 group compared to the BM8 and control groups. These results suggest that administration of B. subtilis strains in the rearing water confers beneficial effects for shrimp aquaculture, considering water quality, growth performance, digestive enzymatic activity, immune response and disease resistance. PMID:24161773

  6. Modeling and prediction for the acute toxicity of pesticide mixtures to the freshwater luminescent bacterium Vibrio qinghaiensis sp.-Q67

    Microsoft Academic Search

    Xuefei Zhou; Wenjing Sang; Shushen Liu; Yalei Zhang; Huilin Ge

    2010-01-01

    In China, water pollution by pesticide mixtures has constituted a serious environmental problem due to potential toxicity and bioaccumulation. But few pesticide combinations have exactly similar and dissimilar mechanisms of action. For this purpose, in tests with the freshwater luminescent bacterium (Vibrio qinghaiensis sp.-Q67), ten pesticides, including three herbicides and seven insecticides, were selected as test substances. Concentration response analysis

  7. Genome sequence of Vibrio diabolicus and identification of the exopolysaccharide HE800 biosynthesis locus.

    PubMed

    Goudenège, David; Boursicot, Vincent; Versigny, Typhaine; Bonnetot, Sandrine; Ratiskol, Jacqueline; Sinquin, Corinne; LaPointe, Gisèle; Le Rous, Frédérique; Roux, Frédérique Le; Delbarre-Ladrat, Christine

    2014-12-01

    Vibrio diabolicus, a marine bacterium originating from deep-sea hydrothermal vents, produces the HE800 exopolysaccharide with high value for biotechnological purposes, especially for human health. Its genome was sequenced and analyzed; phylogenetic analysis using the core genome revealed V. diabolicus is close to another deep-sea Vibrio sp. (Ex25) within the Harveyi clade and Alginolyticus group. A genetic locus homologous to the syp cluster from Vibrio fischeri was demonstrated to be involved in the HE800 production. However, few genetic particularities suggest that the regulation of syp expression may be different in V. diabolicus. The presence of several types of glycosyltransferases within the locus indicates a capacity to generate diversity in the glycosidic structure, which may confer an adaptability to environmental conditions. These results contribute to better understanding exopolysaccharide biosynthesis and for developing new efficient processes to produce this molecule for biotechnological applications. PMID:25273176

  8. Acute toxicity evaluation of explosive wastewater by bacterial bioluminescence assays using a freshwater luminescent bacterium, Vibrio qinghaiensis sp. Nov.

    PubMed

    Ye, Zhengfang; Zhao, Quanlin; Zhang, Mohe; Gao, Yuchen

    2011-02-28

    The compositions of explosive wastewater generated from TNT (2,4,6-trinitrotoluene) purification stage were characterized by using UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), high performance liquid chromatograph (HPLC) and gas chromatograph/mass spectroscopy (GC/MS). The acute toxicity was evaluated by bacterium bioluminescence assay using a freshwater luminescent bacterium (Vibrio qinghaiensis sp. Nov.) and a marine luminescent bacterium (Photobacterium phosphoreum). The results showed that the wastewater's biodegradability was poor due to the high amount of chemical oxygen demand (COD). The main organic components were dinitrotoluene sulfonates (DNTS) with small amount of TNT, dinitrotoluene (DNT), mononitrotoluene (MNT) and other derivatives of nitrobenzene. It was highly toxic to luminescent bacteria P. phosphoreum and V. qinghaiensis sp. Nov. After reaction time of 15 min, the relative concentration of toxic pollutants (expressed as reciprocal of dilution ratio of wastewater) at 50% of luminescence inhibition ratio was 5.32×10(-4) for P. phosphoreu, while that was 4.34×10(-4) for V. qinghaiensis. V. qinghaiensis is more sensitive and suitable for evaluating the wastewater's acute toxicity than P. phosphoreum. After adsorption by resin, the acute toxicity can be greatly reduced, which is helpful for further treatment by biological methods. PMID:21185645

  9. Vibrio alginolyticus , a tetrodotoxin-producing bacterium, in the intestines of the fish Fugu vermicularis vermicularis

    Microsoft Academic Search

    T. Noguchi; D. F. Hwang; O. Arakawa; H. Sugita; Y. Deguchi; Y. Shida; K. Hashimoto

    1987-01-01

    To clarify the mechanism of toxification in animals contaminated with tetrodotoxin, the intestinal contents of the puffer Fugu vermicularis vermicularis were examined for bacterial flora in 1985. Twenty-six out of 33 strains belonged to the genus Vibrio. These bacteria were classified into Groups I to VII, based on biological and biochemical characters. High performance liquid chromatography and gas chromatography-mass spectrometry,

  10. Acute Toxicity Bioassay Using the Freshwater Luminescent Bacterium Vibrio-qinghaiensis sp. Nov.—Q67

    Microsoft Academic Search

    M. Ma; Z. Tong; Z. Wang; W. Zhu

    1999-01-01

    ®assay system (Bulich, 1979) which is based on the measurement of the reduction in light emission of the luminescent bacteria Vibrio fischeri after contact with a toxicant. It has been widely used as a reproducible and sensitive screening method to determine overall toxicity from different types of samples. In China, the most commonly used strain for this kind of bioassay

  11. IbpA\\/B Small Heat-Shock Protein of Marine Bacterium Vibrio harveyi Binds to Proteins Aggregated in a Cell During Heat Shock

    Microsoft Academic Search

    Gracjana Klein; Ewa Laskowska; Alina Taylor; Barbara Lipi?ska

    2001-01-01

    :   The IbpA and IbpB are 16-kDa Escherichia coli proteins belonging to a family of small heat-shock proteins (sHsps). According to the present model, based on the in vitro\\u000a experiments, sHsps are molecular chaperones that bind and prevent aggregation of nonnative proteins during heat shock. Previously,\\u000a we have shown that IbpA and IbpB bind to endogenous E. coli proteins aggregated

  12. Vibrio psychroerythrus sp. n.: Classification of the Psychrophilic Marine Bacterium, NRC 1004

    PubMed Central

    D'aoust, J. Y.; Kushner, D. J.

    1972-01-01

    A red-pigmented organism, formerly known as marine psychrophile NRC 1004, has been classified as Vibrio psychroerythrus sp. n. Classification was mainly based on morphology, the ability of the organism to oxidize and ferment glucose, its sensitivity to vibriostat 0/129, and its deoxyribonucleic acid base composition of 40.0 moles% guanine plus cytosine, determined by thermal denaturation. The organism gave positive reactions for catalase, oxidase, and starch hydrolysis and produced acid from maltose and dextrin but not from arabinose. It was indole- and citrate-negative and reduced nitrate to nitrite without producing gas. PMID:5053463

  13. Experimental and predicted acute toxicity of antibacterial compounds and their mixtures using the luminescent bacterium Vibrio fischeri.

    PubMed

    Villa, Sara; Vighi, Marco; Finizio, Antonio

    2014-08-01

    This article investigates the bioluminescence inhibition effects of the antimicrobials triclocarban, triclosan and its metabolite methyl triclosan, using the marine bacterium Vibrio fischeri as the test organism (Microtox©). The concentration response analysis was performed for the three individual substances and for a mixture in which the three compounds were mixed in a ratio of the IC50 of the individual components (equitoxic ratio). Toxicity values (the median inhibitory concentration value, in mg L(-1)) in the decreasing order of sensitivity were triclosan (0.73)>triclocarban (0.91)>methyl-triclosan (1.76). The comparison of the experimental data with those obtained by using Quantitative Structure-Activity Relationship (QSAR) equations indicated that triclosan and triclocarban act as polar narcotic compounds towards V. fischeri, whereas methyl-triclosan acts as a narcotic (baseline toxicity). The toxicity of the mixture was measured experimentally and predicted by two models (CA: concentration addition; IA: independent action). The results showed that the observed mixture toxicity (IC50=0.23 mg L(-1)) had no significant differences from those predicted by both CA and IA models. PMID:24529397

  14. A new esterase showing similarity to putative dienelactone hydrolase from a strict marine bacterium, Vibrio sp. GMD509.

    PubMed

    Park, Sang-Yi; Kim, Jun-Tae; Kang, Sung Gyun; Woo, Jung-Hee; Lee, Jung-Hyun; Choi, Hyoung-Tae; Kim, Sang-Jin

    2007-11-01

    Vibrio sp. GMD509, a marine bacterium isolated from eggs of the sea hare, exhibited lipolytic activity on tributyrin (TBN) plate, and the gene representing lipolytic activity was cloned. As a result, an open reading frame (ORF) consisting of 1,017 bp (338 aa) was found, and the deduced amino acid sequence of the ORF showed low similarity (< 20%) to alpha/beta hydrolases such as dienelactone hydrolases and esterase/lipase with G-X(1)-S-X(2)-G sequence conserved. Phylogenetic analysis suggested that the protein belonged to a new family of esterase/lipase together with various hypothetical proteins. The enzyme was overexpressed in Escherichia coli and purified to homogeneity. The purified enzyme (Vlip509) showed the best hydrolyzing activity toward p-nitrophenyl butyrate (C(4)) among various p-nitrophenyl esters (C(2) to C(18)), and optimal activity of Vlip509 occurred at 30 degrees C and pH 8.5, respectively. Kinetic parameters toward p-nitrophenyl butyrate were determined as K (m) (307 muM), k (cat) (5.72 s(-1)), and k (cat)/K (m) (18.61 s(-1) mM(-1)). Furthermore, Vlip509 preferentially hydrolyzed the S-enantiomer of racemic ofloxacin ester. Despite its sequence homology to dienelactone hydrolase, Vlip509 showed no dienelactone hydrolase activity. This study represents the identification of a novel lipolytic enzyme from marine environment. PMID:17712554

  15. Characterizing the Host and Symbiont Proteomes in the Association between the Bobtail Squid, Euprymna scolopes, and the Bacterium, Vibrio fischeri

    PubMed Central

    Schleicher, Tyler R.; Nyholm, Spencer V.

    2011-01-01

    The beneficial symbiosis between the Hawaiian bobtail squid, Euprymna scolopes, and the bioluminescent bacterium, Vibrio fischeri, provides a unique opportunity to study host/microbe interactions within a natural microenvironment. Colonization of the squid light organ by V. fischeri begins a lifelong association with a regulated daily rhythm. Each morning the host expels an exudate from the light organ consisting of 95% of the symbiont population in addition to host hemocytes and shed epithelial cells. We analyzed the host and symbiont proteomes of adult squid exudate and surrounding light organ epithelial tissue using 1D- and 2D-polyacrylamide gel electrophoresis and multidimensional protein identification technology (MudPIT) in an effort to understand the contribution of both partners to the maintenance of this association. These proteomic analyses putatively identified 1581 unique proteins, 870 proteins originating from the symbiont and 711 from the host. Identified host proteins indicate a role of the innate immune system and reactive oxygen species (ROS) in regulating the symbiosis. Symbiont proteins detected enhance our understanding of the role of quorum sensing, two-component signaling, motility, and detoxification of ROS and reactive nitrogen species (RNS) inside the light organ. This study offers the first proteomic analysis of the symbiotic microenvironment of the adult light organ and provides the identification of proteins important to the regulation of this beneficial association. PMID:21998678

  16. A Novel Algicide: Evidence of the Effect of a Fatty Acid Compound from the Marine Bacterium, Vibrio sp. BS02 on the Harmful Dinoflagellate, Alexandrium tamarense

    PubMed Central

    Fu, Lijun; An, Xinli; Zhang, Bangzhou; Li, Yi; Chen, Zhangran; Zheng, Wei; Yi, Lin; Zheng, Tianling

    2014-01-01

    Alexandrium tamarense is a notorious bloom-forming dinoflagellate, which adversely impacts water quality and human health. In this study we present a new algicide against A. tamarense, which was isolated from the marine bacterium Vibrio sp. BS02. MALDI-TOF-MS, NMR and algicidal activity analysis reveal that this compound corresponds to palmitoleic acid, which shows algicidal activity against A. tamarense with an EC50 of 40 ?g/mL. The effects of palmitoleic acid on the growth of other algal species were also studied. The results indicate that palmitoleic acid has potential for selective control of the Harmful algal blooms (HABs). Over extended periods of contact, transmission electron microscopy shows severe ultrastructural damage to the algae at 40 ?g/mL concentrations of palmitoleic acid. All of these results indicate potential for controlling HABs by using the special algicidal bacterium and its active agent. PMID:24626054

  17. Genome Sequence of Vibrio campbellii Strain UMTGB204, a Marine Bacterium Isolated from a Green Barrel Tunicate.

    PubMed

    Gan, Huan You; Noor, Mohd Ezhar Mohd; Saari, Nur Azna; Musa, Najiah; Mustapha, Baharim; Usup, Gires; Danish-Daniel, Muhd

    2015-01-01

    Vibrio campbellii strain UMTGB204 was isolated from a green barrel tunicate. The genome of this strain comprises 5,652,224 bp with 5,014 open reading frames, 9 rRNAs, and 116 tRNAs. It contains genes related to virulence and environmental tolerance. Gene clusters for the biosynthesis of nonribosomal peptides and bacteriocin were also identified. PMID:25814609

  18. Genome Sequence of Vibrio campbellii Strain UMTGB204, a Marine Bacterium Isolated from a Green Barrel Tunicate

    PubMed Central

    Gan, Huan You; Noor, Mohd Ezhar Mohd; Saari, Nur Azna; Musa, Najiah; Mustapha, Baharim; Usup, Gires

    2015-01-01

    Vibrio campbellii strain UMTGB204 was isolated from a green barrel tunicate. The genome of this strain comprises 5,652,224 bp with 5,014 open reading frames, 9 rRNAs, and 116 tRNAs. It contains genes related to virulence and environmental tolerance. Gene clusters for the biosynthesis of nonribosomal peptides and bacteriocin were also identified. PMID:25814609

  19. Characterisation of a Marine Bacterium Vibrio Brasiliensis T33 Producing N-acyl Homoserine Lactone Quorum Sensing Molecules

    PubMed Central

    Tan, Wen-Si; Yunos, Nina Yusrina Muhamad; Tan, Pui-Wan; Mohamad, Nur Izzati; Adrian, Tan-Guan-Sheng; Yin, Wai-Fong; Chan, Kok-Gan

    2014-01-01

    N-acylhomoserine lactones (AHL) plays roles as signal molecules in quorum sensing (QS) in most Gram-negative bacteria. QS regulates various physiological activities in relation with population density and concentration of signal molecules. With the aim of isolating marine water-borne bacteria that possess QS properties, we report here the preliminary screening of marine bacteria for AHL production using Chromobacterium violaceum CV026 as the AHL biosensor. Strain T33 was isolated based on preliminary AHL screening and further identified by using 16S rDNA sequence analysis as a member of the genus Vibrio closely related to Vibrio brasiliensis. The isolated Vibrio sp. strain T33 was confirmed to produce N-hexanoyl-l-homoserine lactone (C6-HSL) and N-(3-oxodecanoyl)-l-homoserine lactone (3-oxo-C10 HSL) through high resolution tandem mass spectrometry analysis. We demonstrated that this isolate formed biofilms which could be inhibited by catechin. To the best of our knowledge, this is the first report that documents the production of these AHLs by Vibrio brasiliensis strain T33. PMID:25006994

  20. Vibrio vulnificus

    Microsoft Academic Search

    James D. Oliver

    Vibrio vulnificus presents a significant public health risk to certain persons consuming raw or undercooked seafood, or who acquire wound infections\\u000a while involved in aquatic activities in coastal or estuarine waters. This review describes the bacterium's taxonomy, the three\\u000a types of infection it is capable of producing, the virulence factors known or speculated to be involved in these infections,\\u000a its

  1. Dynamic Localization of MreB in Vibrio parahaemolyticus and in the Ectopic Host Bacterium Escherichia coli

    Microsoft Academic Search

    Shen-Wen Chiu; Shau-Yan Chen; Hin-chung Wong

    2008-01-01

    MreB, a homolog of eukaryotic actin, participates in morphogenesis, cell division, cell polarity, and chromosome segregation in prokaryotes. In this study, a yellow fluorescent protein conjugate (YFP-MreBVp) was generated to investigate the behavior of MreB in merodiploid strain SC9 of the enteropathogen Vibrio parahaemolyticus. Under normal growth conditions, YFP-MreBVp formed helical filaments with a pitch of 0.64 0.09 m in

  2. Na +-driven multidrug efflux pump VcmA from Vibrio cholerae non-O1, a non-halophilic bacterium

    Microsoft Academic Search

    M. Nazmul Huda; Yuji Morita; Teruo Kuroda; Tohru Mizushima; Tomofusa Tsuchiya

    2001-01-01

    A chromosomal DNA fragment from Vibrio cholerae non-O1 containing a drug resistance determinant was cloned and sequenced. The deduced amino acid sequence suggested that the determinant gene encodes a multidrug efflux pump. We designated the pump VcmA. Escherichia coli cells transformed with a plasmid carrying the vcmA gene showed increased resistance against norfloxacin, ciprofloxacin, ofloxacin, daunomycin, doxorubicin, streptomycin, kanamycin, ethidium

  3. Antibiofilm Activity of the Marine Bacterium Pseudoalteromonas sp. 3J6 Against Vibrio tapetis, the Causative Agent of Brown Ring Disease.

    PubMed

    Rodrigues, Sophie; Paillard, Christine; Dufour, Alain; Bazire, Alexis

    2015-03-01

    Vibrio tapetis CECT4600 is a pathogenic Gram-negative bacterium causing the brown ring disease in the Manila clam Ruditapes philippinarum. This vibriosis is induced by bacterial attachment on the periostracal lamina, yielding a decalcification of the bivalve shell. As in many bacterial species, pathogenesis is likely related to biofilm formation. The proteinaceous exoproducts of the marine bacterium Pseudoalteromonas sp. 3J6 inhibit the formation of biofilm by most of the tested marine bacteria without affecting their planktonic growth. In the present work, we examined the sensitivity of V. tapetis to Pseudoalteromonas sp. 3J6 and its exoproducts. In V. tapetis CECT4600-GFP-Pseudoalteromonas sp. 3J6 co-cultures, the latter outcompeted V. tapetis whatever the growth mode (planktonic or biofilm), which could result from a slower growth of V. tapetis. Biofilms containing only V. tapetis were grown in vitro on a glass substratum under dynamic conditions. When the glass was coated with a culture supernatant of Pseudoalteromonas sp. 3J6 (SN3J6) prior to inoculating V. tapetis CECT4600-GFP, the bacterial attachment was about fivefold lower than in control experiment without SN3J6 and the biofilm formation was delayed by about 24 h: A full biofilm was obtained at 48 versus 24 h for the control. Moreover, a preformed V. tapetis biofilm (grown on SN3J6-free glass substratum) could be disrupted by incubating it with SN3J6. This data suggest that Pseudoalteromonas sp. 3J6 is a good candidate to set up an anti-V. tapetis strategy usable in aquaculture to grow V. tapetis-free Manila clam spats. PMID:25331987

  4. Modeling and prediction for the acute toxicity of pesticide mixtures to the freshwater luminescent bacterium Vibrio qinghaiensis sp.-Q67.

    PubMed

    Zhou, Xuefei; Sang, Wenjing; Liu, Shushen; Zhang, Yalei; Ge, Huilin

    2010-01-01

    In China, water pollution by pesticide mixtures has constituted a serious environmental problem due to potential toxicity and bioaccumulation. But few pesticide combinations have exactly similar and dissimilar mechanisms of action. For this purpose, in tests with the freshwater luminescent bacterium (Vibrio qinghaiensis sp.-Q67), ten pesticides, including three herbicides and seven insecticides, were selected as test substances. Concentration response analysis was performed for ten individual substances, and for mixtures containing all ten substances in twelve different concentration ratios (based on UDCR and EECR methods). The observed mixture toxicity was compared with predictions by the two models, concentration addition (CA) and independent action (IA). The toxicity of the tested mixtures showed a good agreement with those predicted by the concept of CA except four UDCR mixtures: UD10-2, UD10-4, UD10-8 and UD10-10. To examine the influence of imidacloprid in the four UDCR mixtures (UD10-2, UD10-4, UD10-8, UD10-10), it was removed from the ten-pesticide mixtures and the remaining nine chemicals were combined at the same relative proportions based on the UDCR method (UD9-2, UD9-4, UD9-8, UD9-10). There was not significant departure from CA for the scattered points with the nine remaining pesticides omitting imidacloprid. Thus, imidacloprid may significantly influence the other pesticides due to its properties. PMID:20614787

  5. Polysiphonia harveyi, WNC2005-126

    NSDL National Science Digital Library

    Dr. Wilson Freshwater

    2008-03-07

    WNC2005-126, Polysiphonia harveyi J. Bailey, Floating docks at Banks Channel, Wrightville Beach, New Hanover County, NC, 30 Jan 2005, Coll: DW Freshwater & B Stuercke, Det: DW Freshwater & B Stuercke, Poly NC6

  6. Isolation and physico-chemical characterisation of extracellular polymeric substances produced by the marine bacterium Vibrio parahaemolyticus.

    PubMed

    Kavita, Kumari; Mishra, Avinash; Jha, Bhavanath

    2011-03-01

    A marine bacterial strain identified as Vibrio parahaemolyticus by 16S rRNA gene (HM355955) sequencing and gas chromatography (GC) coupled with MIDI was selected from a natural biofilm by its capability to produce extracellular polymeric substances (EPS). The EPS had an average molecule size of 15.278 ?m and exhibited characteristic diffraction peaks at 5.985°, 9.150° and 22.823°, with d-spacings of 14.76661, 9.29989 and 3.89650 Å, respectively. The Fourier-transform infrared spectroscopy (FTIR) spectrum revealed aliphatic methyl, primary amine, halide groups, uronic acid and saccharides. Gas chromatography mass spectrometry (GCMS) confirmed the presence of arabinose, galactose, glucose and mannose. (1)HNMR (nuclear magnetic resonance) revealed functional groups characteristic of polysaccharides. The EPS were amorphous in nature (CI(xrd) 0.092), with a 67.37% emulsifying activity, thermostable up to 250°C and displayed pseudoplastic rheology. MALDI-TOF-TOF analysis revealed a series of masses, exhibiting low-mass peaks (m/z) corresponding to oligosaccharides and higher-mass peaks for polysaccharides consisting of different ratios of pentose and hexose moieties. This is the first report of a detailed characterisation of the EPS produced by V. parahaemolyticus, which could be further explored for biotechnological and industrial use. PMID:21409653

  7. Aposymbiotic culture of the sepiolid squid Euprymna scolopes: role of the symbiotic bacterium Vibrio fischeri in host animal growth, development, and light organ morphogenesis.

    PubMed

    Claes, M F; Dunlap, P V

    2000-02-15

    The sepiolid squid Euprymna scolopes forms a bioluminescent mutualism with the luminous bacterium Vibrio fischeri, harboring V. fischeri cells in a complex ventral light organ and using the bacterial light in predator avoidance. To characterize the contribution of V. fischeri to the growth and development of E. scolopes and to define the long-term effects of bacterial colonization on light organ morphogenesis, we developed a mariculture system for the culture of E. scolopes from hatching to adulthood, employing artificial seawater, lighting that mimicked that of the natural environment, and provision of prey sized to match the developmental stage of E. scolopes. Animals colonized by V. fischeri and animals cultured in the absence of V. fischeri (aposymbiotic) grew and survived equally well, developed similarly, and reached sexual maturity at a similar age. Development of the light organ accessory tissues (lens, reflectors, and ink sac) was similar in colonized and aposymbiotic animals with no obvious morphometric or histological differences. Colonization by V. fischeri influenced regression of the ciliated epithelial appendages (CEAs), the long-term growth of the light organ epithelial tubules, and the appearance of the cells composing the ciliated ducts, which exhibit characteristics of secretory tissue. In certain cases, aposymbiotic animals retained the CEAs in a partially regressed state and remained competent to initiate symbiosis with V. fischeri into adulthood. In other cases, the CEAs regressed fully in aposymbiotic animals, and these animals were not colonizable. The results demonstrate that V. fischeri is not required for normal growth and development of the animal or for development of the accessory light organ tissues and that morphogenesis of only those tissues coming in contact with the bacteria (CEAs, ciliated ducts, and light organ epithelium) is altered by bacterial colonization of the light organ. Therefore, V. fischeri apparently makes no major metabolic contribution to E. scolopes beyond light production, and post-embryonic development of the light organ is essentially symbiont independent. J. Exp. Zool. 286:280-296, 2000. PMID:10653967

  8. Genomic taxonomy of vibrios

    PubMed Central

    Thompson, Cristiane C; Vicente, Ana Carolina P; Souza, Rangel C; Vasconcelos, Ana Tereza R; Vesth, Tammi; Alves, Nelson; Ussery, David W; Iida, Tetsuya; Thompson, Fabiano L

    2009-01-01

    Background Vibrio taxonomy has been based on a polyphasic approach. In this study, we retrieve useful taxonomic information (i.e. data that can be used to distinguish different taxonomic levels, such as species and genera) from 32 genome sequences of different vibrio species. We use a variety of tools to explore the taxonomic relationship between the sequenced genomes, including Multilocus Sequence Analysis (MLSA), supertrees, Average Amino Acid Identity (AAI), genomic signatures, and Genome BLAST atlases. Our aim is to analyse the usefulness of these tools for species identification in vibrios. Results We have generated four new genome sequences of three Vibrio species, i.e., V. alginolyticus 40B, V. harveyi-like 1DA3, and V. mimicus strains VM573 and VM603, and present a broad analyses of these genomes along with other sequenced Vibrio species. The genome atlas and pangenome plots provide a tantalizing image of the genomic differences that occur between closely related sister species, e.g. V. cholerae and V. mimicus. The vibrio pangenome contains around 26504 genes. The V. cholerae core genome and pangenome consist of 1520 and 6923 genes, respectively. Pangenomes might allow different strains of V. cholerae to occupy different niches. MLSA and supertree analyses resulted in a similar phylogenetic picture, with a clear distinction of four groups (Vibrio core group, V. cholerae-V. mimicus, Aliivibrio spp., and Photobacterium spp.). A Vibrio species is defined as a group of strains that share > 95% DNA identity in MLSA and supertree analysis, > 96% AAI, ? 10 genome signature dissimilarity, and > 61% proteome identity. Strains of the same species and species of the same genus will form monophyletic groups on the basis of MLSA and supertree. Conclusion The combination of different analytical and bioinformatics tools will enable the most accurate species identification through genomic computational analysis. This endeavour will culminate in the birth of the online genomic taxonomy whereby researchers and end-users of taxonomy will be able to identify their isolates through a web-based server. This novel approach to microbial systematics will result in a tremendous advance concerning biodiversity discovery, description, and understanding. PMID:19860885

  9. Defences against oxidative stress in vibrios associated with corals.

    PubMed

    Munn, Colin B; Marchant, Hannah K; Moody, A John

    2008-04-01

    Bacteria colonizing healthy coral tissue may produce enzymes capable of overcoming the toxic effects of reactive oxygen species, including superoxide dismutase (SOD) and catalase. Significant differences in the activities of these enzymes were observed in cultures of Vibrio campbellii, Vibrio coralliilyticus, Vibrio harveyi, Vibrio mediterranei, Vibrio pelagius, Vibrio rotiferanus, Vibrio tasmaniensis, and Photobacterium eurosenbergii isolated from healthy, bleached or necrotic tropical and cold water corals. Levels of SOD in exponential phase cultures of V. coralliilyticus grown at 28 degrees C were only slightly higher than those grown at 16 degrees C whereas the levels in stationary phase cultures at 28 degrees C were 7.3 x higher than those at 16 degrees C. The increase in catalase activity of V. coralliilyticus and V. harveyi upon entry to stationary phase conferred protection against killing by oxidative stress. Increased temperature affected up-regulation of enzymes in stationary phase cultures, but pretreatment of cultures with hydrogen peroxide had no significant effect on induction of catalase or SOD. The increased activities appear to be due to up-regulation of gene expression rather than induction of different forms of the enzymes. We suggest that SOD and catalase are unlikely to be major factors in the virulence of these bacteria for corals and that their main function may be to protect against endogenous superoxide. PMID:18279336

  10. Cloning of a Novel Gene Encoding ?-1,3-Xylosidase from a Marine Bacterium, Vibrio sp. Strain XY-214, and Characterization of the Gene Product?

    PubMed Central

    Umemoto, Yoshiaki; Onishi, Ryosuke; Araki, Toshiyoshi

    2008-01-01

    The ?-1,3-xylosidase gene (xloA) of Vibrio sp. strain XY-214 was cloned and expressed in Escherichia coli. The xloA gene consisted of a 1,608-bp nucleotide sequence encoding a protein of 535 amino acids with a predicted molecular weight of 60,835. The recombinant ?-1,3-xylosidase hydrolyzed ?-1,3-xylooligosaccharides to d-xylose as a final product. PMID:17993567

  11. Mortalities of eastern and pacific oyster larvae caused by the pathogens Vibrio coralliilyticus and Vibrio tubiashii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vibrio tubiashii is reported to be a bacterial pathogen of larval Eastern oysters (Crassostrea virginica) and Pacific oysters (Crassostrea gigas) and has been associated with major hatchery crashes, causing shortages in seed oysters for commercial shellfish producers. Another bacterium, Vibrio cora...

  12. Na+-driven multidrug efflux pump VcmA from Vibrio cholerae non-O1, a non-halophilic bacterium.

    PubMed

    Huda, M N; Morita, Y; Kuroda, T; Mizushima, T; Tsuchiya, T

    2001-09-25

    A chromosomal DNA fragment from Vibrio cholerae non-O1 containing a drug resistance determinant was cloned and sequenced. The deduced amino acid sequence suggested that the determinant gene encodes a multidrug efflux pump. We designated the pump VcmA. Escherichia coli cells transformed with a plasmid carrying the vcmA gene showed increased resistance against norfloxacin, ciprofloxacin, ofloxacin, daunomycin, doxorubicin, streptomycin, kanamycin, ethidium bromide, 4',6-diamidino-2-phenylindole dihydrochloride, Hoechst 33342 and acriflavine. Na+ (or Li+)-dependent efflux of ethidium bromide was detected in transformant cells. Efflux of Na+, elicited by ethidium bromide, was observed from transformant cells. Thus, we concluded that the VcmA is a Na+/drug antiporter. PMID:11583854

  13. Vibrios Associated with Litopenaeus vannamei Larvae, Postlarvae, Broodstock, and Hatchery Probionts

    PubMed Central

    Vandenberghe, Johan; Verdonck, Linda; Robles-Arozarena, Rocio; Rivera, Gabriel; Bolland, Annick; Balladares, Marcos; Gomez-Gil, Bruno; Calderon, Jorge; Sorgeloos, Patrick; Swings, Jean

    1999-01-01

    Several bacteriological surveys were performed from 1994 to 1996 at different Litopenaeus vannamei hatcheries (in Ecuador) and shrimp farms (in Mexico). Samples were taken from routine productions of healthy and diseased L. vannamei larvae, postlarvae, and their culture environment and from healthy and diseased juveniles and broodstock. In Ecuador, the dominant bacterial flora associated with shrimp larvae showing symptoms of zoea 2 syndrome, mysis mold syndrome, and bolitas syndrome has been determined. Strains were characterized by Biolog metabolic fingerprinting and identified by comparison to a database of 850 Vibrio type and reference strains. A selection of strains was further genotypically fine typed by AFLP. Vibrio alginolyticus is predominantly present in all larval stages and is associated with healthy nauplius and zoea stages. AFLP genetic fingerprinting shows high genetic heterogeneity among V. alginolyticus strains, and the results suggest that putative probiotic and pathogenic strains each have specific genotypes. V. alginolyticus was found to be associated with larvae with the zoea 2 syndrome and the mysis mold syndrome, while different Vibrio species (V. alginolyticus and V. harveyi) are associated with the bolitas syndrome. V. harveyi is associated with diseased postlarvae, juveniles, and broodstock. The identities of the strains identified as V. harveyi by the Biolog system could not be unambiguously confirmed by AFLP genomic fingerprinting. Vibrio strain STD3-988 and one unidentified strain (STD3-959) are suspected pathogens of only juvenile and adult stages. V. parahaemolyticus, Photobacterium damselae, and V. mimicus are associated with juvenile and adult stages. PMID:10347048

  14. Vibrios associated with Litopenaeus vannamei larvae, postlarvae, broodstock, and hatchery probionts.

    PubMed

    Vandenberghe, J; Verdonck, L; Robles-Arozarena, R; Rivera, G; Bolland, A; Balladares, M; Gomez-Gil, B; Calderon, J; Sorgeloos, P; Swings, J

    1999-06-01

    Several bacteriological surveys were performed from 1994 to 1996 at different Litopenaeus vannamei hatcheries (in Ecuador) and shrimp farms (in Mexico). Samples were taken from routine productions of healthy and diseased L. vannamei larvae, postlarvae, and their culture environment and from healthy and diseased juveniles and broodstock. In Ecuador, the dominant bacterial flora associated with shrimp larvae showing symptoms of zoea 2 syndrome, mysis mold syndrome, and bolitas syndrome has been determined. Strains were characterized by Biolog metabolic fingerprinting and identified by comparison to a database of 850 Vibrio type and reference strains. A selection of strains was further genotypically fine typed by AFLP. Vibrio alginolyticus is predominantly present in all larval stages and is associated with healthy nauplius and zoea stages. AFLP genetic fingerprinting shows high genetic heterogeneity among V. alginolyticus strains, and the results suggest that putative probiotic and pathogenic strains each have specific genotypes. V. alginolyticus was found to be associated with larvae with the zoea 2 syndrome and the mysis mold syndrome, while different Vibrio species (V. alginolyticus and V. harveyi) are associated with the bolitas syndrome. V. harveyi is associated with diseased postlarvae, juveniles, and broodstock. The identities of the strains identified as V. harveyi by the Biolog system could not be unambiguously confirmed by AFLP genomic fingerprinting. Vibrio strain STD3-988 and one unidentified strain (STD3-959) are suspected pathogens of only juvenile and adult stages. V. parahaemolyticus, Photobacterium damselae, and V. mimicus are associated with juvenile and adult stages. PMID:10347048

  15. Structure, gene regulation and environmental response of flagella in Vibrio.

    PubMed

    Zhu, Shiwei; Kojima, Seiji; Homma, Michio

    2013-01-01

    Vibrio species are Gram-negative, rod-shaped bacteria that live in aqueous environments. Several species, such as V. harveyi, V. alginotyticus, and V. splendidus, are associated with diseases in fish or shellfish. In addition, a few species, such as V. cholerae and V. parahaemolyticus, are risky for humans due to infections from eating raw shellfish infected with these bacteria or from exposure of wounds to the marine environment. Bacterial flagella are not essential to live in a culture medium. However, most Vibrio species are motile and have rotating flagella which allow them to move into favorable environments or to escape from unfavorable environments. This review summarizes recent studies about the flagellar structure, function, and regulation of Vibrio species, especially focused on the Na(+)-driven polar flagella that are principally responsible for motility and sensing the surrounding environment, and discusses the relationship between flagella and pathogenicity. PMID:24400002

  16. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...from cultured isolates derived from clinical specimens. The identification aids in the diagnosis of cholera caused by the bacterium Vibrio cholerae and provides epidemiological information on cholera. Cholera is an acute infectious disease...

  17. Vibrio parahaemolyticus

    MedlinePLUS

    ... Foodnet Data Reports Trends, Data Tables, and Figures Select MMWR Articles CDC. Vibrio parahaemolyticus infections associated with ... Pacific Northwest, 1997 . MMWR 1998;47:457-462. Select CDC References Baker-Austin C. Spread of Pacific ...

  18. Vibrio vulnificus

    MedlinePLUS

    ... Foodnet Data Reports Trends, Data Tables, and Figures Select MMWR Articles Vibrio vulnificus Infections Associated with Eating ... MMWR June 4, 1993 / Vol. 42 / No. 21 Select CDC References Vugia DJ, Tabnak F, Newton AE, ...

  19. Isolation of Vibrio alginolyticus from seawater aquaria

    Microsoft Academic Search

    Stefan Hörmansdorfer; Helmut Wentges; Karin Neugebaur-Büchler; Johann Bauer

    2000-01-01

    The seawater bacterium Vibrio alginolyticus was detected in 5 of 20 water samples from seawater aquaria (from 3 of 5 units) and also from the surface of diseased stony corals. A total of 45 isolates were differentiated biochemically, of which 13 isolates (29%) proved to be V. alginolyticus. All those strains produced the virulence factors caseinase and lipase, 11 strains

  20. Transcriptomic profiling of the oyster pathogen Vibrio splendidus opens a window on the evolutionary dynamics of the small RNA repertoire in the Vibrio genus

    PubMed Central

    Toffano-Nioche, Claire; Nguyen, An N.; Kuchly, Claire; Ott, Alban; Gautheret, Daniel; Bouloc, Philippe; Jacq, Annick

    2012-01-01

    Work in recent years has led to the recognition of the importance of small regulatory RNAs (sRNAs) in bacterial regulation networks. New high-throughput sequencing technologies are paving the way to the exploration of an expanding sRNA world in nonmodel bacteria. In the Vibrio genus, compared to the enterobacteriaceae, still a limited number of sRNAs have been characterized, mostly in Vibrio cholerae, where they have been shown to be important for virulence, as well as in Vibrio harveyi. In addition, genome-wide approaches in V. cholerae have led to the discovery of hundreds of potential new sRNAs. Vibrio splendidus is an oyster pathogen that has been recently associated with massive mortality episodes in the French oyster growing industry. Here, we report the first RNA-seq study in a Vibrio outside of the V. cholerae species. We have uncovered hundreds of candidate regulatory RNAs, be it cis-regulatory elements, antisense RNAs, and trans-encoded sRNAs. Conservation studies showed the majority of them to be specific to V. splendidus. However, several novel sRNAs, previously unidentified, are also present in V. cholerae. Finally, we identified 28 trans sRNAs that are conserved in all the Vibrio genus species for which a complete genome sequence is available, possibly forming a Vibrio “sRNA core.” PMID:23097430

  1. Enrichment of Artemia nauplii with the probiotic yeast Saccharomyces boulardii and its resistance against a pathogenic Vibrio

    Microsoft Academic Search

    S. K. Patra; K. S. Mohamed

    2003-01-01

    Enrichment of Artemia nauplii with a known probiotic yeast Saccharomyces boulardii (SB) and its role in enhancing resistance against the pathogen Vibrio\\u000a harveyi was investigated. SB was cultured, then fed to instar II Artemia nauplii in three different treatments; 102 (T1), 103 (T2) and 104 (T3) colony forming units (CFU) per ml in triplicate. The algae Nanochloropsis sp. was used

  2. Radiofrequency transmission line for bioluminescent Vibrio sp. irradiation

    NASA Astrophysics Data System (ADS)

    Nassisi, V.; Alifano, P.; Talà, A.; Velardi, L.

    2012-07-01

    We present the study and the analyses of a transmission line for radiofrequency (RF) irradiation of bacteria belonging to Vibrio harveyi-related strain PS1, a bioluminescent bacterium living in symbiosis with many marine organisms. The bioluminescence represents a new biologic indicator which is useful for studying the behaviour of living samples in the presence of RF waves due to the modern communication systems. A suitable transmission line, used as an irradiating cell and tested up to the maximum frequency used by the global system for mobile communications and universal mobile telecommunications system transmissions, was characterized. In this experiment, the RF voltage applied to the transmission line was 1 V. Due to short dimensions of the line and the applied high frequencies, standing waves were produced in addition to progressing waves and the electric field strength varies particularly along the longitudinal direction. The magnetic field map was not strongly linked to the electric one due to the presence of standing waves and of the outgoing irradiation. RF fields were measured by two homemade suitable probes able to diagnostic fields of high frequency. The field measurements were performed without any specimens inside the line. Being our sample made of living matter, the real field was modified and its value was estimated by a simulation code. The bioluminescence experiments were performed only at 900 MHz for two different measured electric fields, 53 and 140 V/m. The light emission was measured right from the beginning and after 7 and 25 h. Under RF irradiation, we found that the bioluminescence activity decreased. Compared with the control sample, the diminution was 6.8% and 44% after 7 and 25 h of irradiation, respectively, both with the low or high field. No changes of the survival factor for all the samples were observed. Besides, to understand the emission processes, we operated the deconvolution of the spectra by two Gaussian curves. The Gaussian peaks were approximately centered at 460 nm and 490 nm. The 490 nm peak was higher than the control one. Under RF, the 490 nm peak decreased compared to the 460 nm one. The decreasing was stronger for the sample in the higher field. The ratio of the emission area of the 490 nm to 460 nm was 5 for the control sample. It decreased up to 1.6 for the samples under RF. The bioluminescence improves the DNA repair by photoreactivation, and there is evidence that photolyase is preferentially activated by blue/violet light. Our finding suggests that RF exposure may stimulate DNA repair by shifting the emission spectra from blue/green (490 nm) to blue/violet (460 nm).

  3. Role for cheR of Vibrio fischeri in the Vibriosquid Cindy R. DeLoney-Marino and Karen L. Visick

    E-print Network

    McFall-Ngai, Margaret

    symbiotic partner, the biolumines- cent marine bacterium Vibrio fischeri. Vibrio fischeri cells present. In this study, we investigated the role chemotaxis may play in establishing this symbiotic colonization symbiote, la bactérie marine bioluminescente Vibrio fischeri. Les cellules de V. fischeri présentes dans l

  4. Wound Infection due to Vibrio vulnificus in Spain

    Microsoft Academic Search

    L. Torres; S. Escobar; A. I. López; M. L. Marco; V. Pobo

    2002-01-01

    .   \\u000a Vibrio vulnificus is a gram-negative rod that can cause septicaemia and skin lesions, usually in patients with underlying illnesses such as\\u000a chronic liver disease or diabetes mellitus. Infections caused by this bacterium are unusual in Spain. A case of skin infection\\u000a due to Vibrio vulnificus is reported in a patient whose abraded skin on his left leg came

  5. Illuminating Cell Signaling: Using "Vibrio harveyi" in an Introductory Biology Laboratory

    ERIC Educational Resources Information Center

    Hrizo, Stacy L.; Kaufmann, Nancy

    2009-01-01

    Cell signaling is an essential cellular process that is performed by all living organisms. Bacteria communicate with each other using a chemical language in a signaling pathway that allows bacteria to evaluate the size of their population, determine when they have reached a critical mass (quorum sensing), and then change their behavior in unison…

  6. Antimicrobial Resistance in Vibrios

    Microsoft Academic Search

    Michael L. Bennish; Wasif A. Khan; Debasish Saha

    This chapter addresses antimicrobial resistance in a genus – Vibrio – that results in two distinct clinical syndromes. One is profound diarrheal disease – cholera – caused by Vibrio cholerae O1 or O139. The other is often the fatal wound infection and sepsis caused by a variety of halophilic (saltloving) vibrios\\u000a (1) – with V. vulnificus and V. parahaemolyticus perhaps

  7. EFFECTS OF PHYSICOCHEMICAL FACTORS AND BACTERIAL COLONY MORPHOTYPE ON ASSOCIATION OF VIBRIO VULNIFICUS WITH HEMOCYTES OF CRASSOSTREA VIRGINICA

    EPA Science Inventory

    Vibrio vulnificus is a naturally occurring marine bacterium which causes invasive disease of immunocompromised humans following consumption of raw oysters. t is natural flora of Gulf Coast estuaries and has been found to inhabit tissues of oysters, Crassostrea virginica (Gmelin, ...

  8. Lessons from cholera & Vibrio cholerae

    PubMed Central

    Ghose, Asoke C.

    2011-01-01

    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) leading to major discoveries that opened up novel areas of research or new disciplines in biomedical sciences. An attempt is made here to summarize some of these breakthroughs and outline their significance in broader perspectives. Finally, the possible impact of the global socio-political scenario on the spread of cholera epidemics (pandemicity of cholera) is briefly discussed. PMID:21415490

  9. Quorum sensing regulatory cascades control Vibrio fluvialis pathogenesis.

    PubMed

    Wang, Yunduan; Wang, Hui; Liang, Weili; Hay, Amanda J; Zhong, Zengtao; Kan, Biao; Zhu, Jun

    2013-08-01

    Quorum sensing (QS) is a process by which individual bacteria are able to communicate with one another, thereby enabling the population as a whole to coordinate gene regulation and subsequent phenotypic outcomes. Communication is accomplished through production and detection of small molecules in the extracellular milieu. In many bacteria, particularly Vibrio species, multiple QS systems result in multiple signals, as well as cross talk between systems. In this study, we identify two QS systems in the halophilic enteric pathogen Vibrio fluvialis: one acyl-homoserine lactone (AHL) based and one CAI-1/AI-2 based. We show that a LuxI homolog, VfqI, primarily produces 3-oxo-C10-HSL, which is sensed by a LuxR homolog, VfqR. VfqR-AHL is required to activate vfqI expression and autorepress vfqR expression. In addition, we have shown that similar to that in V. cholerae and V. harveyi, V. fluvialis produces CAI-1 and AI-2 signal molecules to activate the expression of a V. cholerae HapR homolog through LuxO. Although VfqR-AHL does not regulate hapR expression, HapR can repress vfqR transcription. Furthermore, we found that QS in V. fluvialis positively regulates production of two potential virulence factors, an extracellular protease and hemolysin. QS also affects cytotoxic activity against epithelial tissue cultures. These data suggest that V. fluvialis integrates QS regulatory pathways to play important physiological roles in pathogenesis. PMID:23749976

  10. rbcL sequences reveal multiple cryptic introductions of the Japanese red alga Polysiphonia harveyi.

    PubMed

    McIvor, L; Maggs, C A; Provan, J; Stanhope, M J

    2001-04-01

    In Europe, the last 20 years have seen a spectacular increase in accidental introductions of marine species, but it has recently been suggested that both the actual number of invaders and their impacts have been seriously underestimated because of the prevalence of sibling species in marine habitats. The red alga Polysiphonia harveyi is regarded as an alien in the British Isles and Atlantic Europe, having appeared in various locations there during the past 170 years. Similar or conspecific populations are known from Atlantic North America and Japan. To choose between three competing hypotheses concerning the origin of P. harveyi in Europe, we employed rbcL sequence analysis in conjunction with karyological and interbreeding data for samples and isolates of P. harveyi and various congeners from the Pacific and North Atlantic Oceans. All cultured isolates of P. harveyi were completely interfertile, and there was no evidence of polyploidy or aneuploidy. Thus, this biological species is both morphologically and genetically variable: intraspecific rbcL divergences of up to 2.1% are high even for red algae. Seven rbcL haplotypes were identified. The four most divergent haplotypes were observed in Japanese samples from Hokkaido and south-central Honshu, which are linked by hypothetical 'missing' haplotypes that may be located in northern Honshu. These data are consistent with Japan being the centre of diversity and origin for P. harveyi. Two non-Japanese lineages were linked to Hokkaido and Honshu, respectively. A single haplotype was found in all North Atlantic and Mediterranean accessions, except for North Carolina, where the haplotype found was the same as that invading in New Zealand and California. The introduction of P. harveyi into New Zealand has gone unnoticed because P. strictissima is a morphologically indistinguishable native sibling species. The sequence divergence between them is 4-5%, greater than between some morphologically distinct red algal species. Two different types of cryptic invasions of P. harveyi have therefore occurred. In addition to its introduction as a cryptic sibling species in New Zealand, P. harveyi has been introduced at least twice into the North Atlantic from presumed different source populations. These two introductions are genetically and probably also physiologically divergent but completely interfertile. PMID:11348500

  11. Phylogeny and Molecular Identification of Vibrios on the Basis of Multilocus Sequence Analysis

    PubMed Central

    Thompson, F. L.; Gevers, D.; Thompson, C. C.; Dawyndt, P.; Naser, S.; Hoste, B.; Munn, C. B.; Swings, J.

    2005-01-01

    We analyzed the usefulness of rpoA, recA, and pyrH gene sequences for the identification of vibrios. We sequenced fragments of these loci from a collection of 208 representative strains, including 192 well-documented Vibrionaceae strains and 16 presumptive Vibrio isolates associated with coral bleaching. In order to determine the intraspecies variation among the three loci, we included several representative strains per species. The phylogenetic trees constructed with the different genetic loci were roughly in agreement with former polyphasic taxonomic studies, including the 16S rRNA-based phylogeny of vibrios. The families Vibrionaceae, Photobacteriaceae, Enterovibrionaceae, and Salinivibrionaceae were all differentiated on the basis of each genetic locus. Each species clearly formed separated clusters with at least 98, 94, and 94% rpoA, recA, and pyrH gene sequence similarity, respectively. The genus Vibrio was heterogeneous and polyphyletic, with Vibrio fischeri, V. logei, and V. wodanis grouping closer to the Photobacterium genus. V. halioticoli-, V. harveyi-, V. splendidus-, and V. tubiashii-related species formed groups within the genus Vibrio. Overall, the three genetic loci were more discriminatory among species than were 16S rRNA sequences. In some cases, e.g., within the V. splendidus and V. tubiashii group, rpoA gene sequences were slightly less discriminatory than recA and pyrH sequences. In these cases, the combination of several loci will yield the most robust identification. We can conclude that strains of the same species will have at least 98, 94, and 94% rpoA, recA, and pyrH gene sequence similarity, respectively. PMID:16151093

  12. Ammonificins A and B, Hydroxyethylamine Chroman Derivatives from a Cultured Marine Hydrothermal Vent Bacterium, ThermoWibrio ammonificans

    E-print Network

    ), were isolated from the marine hydrothermal vent bacterium ThermoVibrio ammonificans. The molecular report of secondary metabolites from the marine hydrothermal vent bacterium T. ammonificans. The oceansAmmonificins A and B, Hydroxyethylamine Chroman Derivatives from a Cultured Marine Hydrothermal

  13. Complete Genome Sequence of Vibrio alginolyticus ATCC 17749T

    PubMed Central

    Liu, Xiao-Fei; Cao, Yuan; Zhang, He-Lin; Chen, Ying-Jian

    2015-01-01

    Vibrio alginolyticus is a Gram-negative halophilic bacterium and has been recognized as an opportunistic pathogen in both humans and marine animals. It is the causative agent of food-borne diseases, such as gastroenteritis, and it invades through wounds in predisposed individuals. In this study, we present the completed genome of V. alginolyticus ATCC 17749T through high-throughput sequencing. PMID:25635021

  14. rbcL sequences reveal multiple cryptic introductions of the Japanese red alga Polysiphonia harveyi

    Microsoft Academic Search

    Lynne McIvor; Christine A. Maggs; Jim Provan; Michael J. Stanhope

    2001-01-01

    In Europe, the last 20 years have seen a spectacular increase in accidental introductions of marine species, but it has recently been suggested that both the actual number of invaders and their impacts have been seriously underestimated because of the prevalence of sibling species in marine habitats. The red alga Polysiphonia harveyi is regarded as an alien in the British

  15. Vibrio and Pregnancy

    MedlinePLUS

    ... Seawater that takes over an area after a hurricane or flood may contain Vibrio bacteria. You should ... from the wound can enter the blood and cause fevers, chills, and blisters. If this infection is ...

  16. Isolation and alga-inhibiting characterization of Vibrio sp. BS02 against Alexandrium tamarense

    Microsoft Academic Search

    Lijun FuXinli; Xinli An; Dong Li; Lijian Zhou; Yun Tian; Tianling Zheng

    The bacterium BS02 which is closely related to the genus Vibrio sp. and capable of inhibiting the toxic dinoflagellate Alexandrium tamarense was isolated from a mangrove area in Zhangjiangkou, Fujian Province, China. The bacterium was not species-specific since\\u000a it displayed varying degrees of lysing activities against eight of the eighteen algae tested. There was a close interaction\\u000a between initial bacterial

  17. NspS, a Predicted Polyamine Sensor, Mediates Activation of Vibrio cholerae Biofilm Formation by Norspermidine

    Microsoft Academic Search

    Ece Karatan; Tammi R. Duncan; Paula I. Watnick

    2005-01-01

    Vibrio cholerae is both an environmental bacterium and a human intestinal pathogen. The attachment of bacteria to surfaces in biofilms is thought to be an important feature of the survival of this bacterium both in the environment and within the human host. Biofilm formation occurs when cell-surface and cell-cell contacts are formed to make a three-dimensional structure characterized by pillars

  18. Survival of Vibrio anguillarum and Vibrio salmonicida at different salinities.

    PubMed Central

    Hoff, K A

    1989-01-01

    The fish pathogenic bacteria Vibrio anguillarum and V. salmonicida showed the capacity to survive for more than 50 and 14 months, respectively, in seawater microcosms. A salinity of 5% proved lethal to V. anguillarum harvested in the late-exponential growth phase, whereas a salinity of 9% was lethal to the bacterium after it had been starved at a salinity of 30% for 67 days. The lethal salinity for V. salmonicida harvested in the late-exponential growth phase was probably in the vicinity of 10%. V. anguillarum and V. salmonicida were very sensitive to nalidixic acid. Direct determination of viable cells after incubation with nalidixic acid was not possible, since the cells did not elongate. Samples of V. salmonicida were double stained with fluorescein isothiocyanate-labeled antibodies and 4',6-diamidino-2-phenylindole. After 3 or 4 days of starvation, there was a discrepancy between the total numbers of cells as determined by immunofluorescence versus by staining with 4',6-diamidino-2-phenylindole. The immunofluorescence counts remained high, which indicated the presence of intact cell envelopes but leakage of DNA and other cytoplasm components. After 2 weeks of starvation, for some of the cells, the region stained with 4',6-diamidino-2-phenylindole (i.e., DNA) was markedly smaller than the cell envelope. I attributed this to a shrinkage of the cytoplasm or a confined nucleoid or both. V. anguillarum lost its exoproteolytic activity before 11 days of starvation. PMID:2475069

  19. Sensitivity of vibrios to sanguinarine

    Microsoft Academic Search

    R. Nandi; M. Maiti; K. Chaudhuri; S. B. Mahato; A. K. Bairagi

    1983-01-01

    Summary The sensitivity to sanguinarine of various strains belonging to 4 vibrio biotypes was investigated.Vibrio cholerae (classical) was most sensitive, andVibrio parahaemolyticus least sensitive to this alkaloid. Statistical analysis revealed significant differences between the 4 biotypes in their sensitivity to sanguinarine.

  20. Enterotoxicity and Cytotoxicity of Vibrio parahaemolyticus Thermostable Direct Hemolysin in In Vitro Systems

    Microsoft Academic Search

    FRANCESCO RAIMONDI; JOSEPH P. Y. KAO; CARLA FIORENTINI; ALESSIA FABBRI; GIANFRANCO DONELLI; NICOLETTA GASPARINI; ARMIDO RUBINO; ALESSIO FASANO

    2000-01-01

    Vibrio parahaemolyticus is a marine bacterium known to be a common cause of seafood gastroenteritis worldwide. The thermostable direct hemolysin (TDH) has been proposed to be a major virulence factor of V. parahaemolyticus. TDH causes intestinal fluid secretion as well as cytotoxicity in a variety of cell types. In this study, we investigated the interplay between the hemolysin's enterotoxic and

  1. Transcription termination Within the iron transport-biosynthesis operon of Vibrio anguillarum requires an antisense RNA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The iron transport-biosynthesis (ITB) operon in Vibrio anguillarum includes four genes for ferric-siderophore transport, fatD,C,B,A, and two genes for siderophorebiosynthesis, angR and angT and plays an important role in the virulence mechanism of this bacterium. Despite being part of the same polyc...

  2. Environmental reservoirs and mechanisms of persistence of Vibrio cholerae

    PubMed Central

    Lutz, Carla; Erken, Martina; Noorian, Parisa; Sun, Shuyang; McDougald, Diane

    2013-01-01

    It is now well accepted that Vibrio cholerae, the causative agent of the water-borne disease cholera, is acquired from environmental sources where it persists between outbreaks of the disease. Recent advances in molecular technology have demonstrated that this bacterium can be detected in areas where it has not previously been isolated, indicating a much broader, global distribution of this bacterium outside of endemic regions. The environmental persistence of V. cholerae in the aquatic environment can be attributed to multiple intra- and interspecific strategies such as responsive gene regulation and biofilm formation on biotic and abiotic surfaces, as well as interactions with a multitude of other organisms. This review will discuss some of the mechanisms that enable the persistence of this bacterium in the environment. In particular, we will discuss how V. cholerae can survive stressors such as starvation, temperature, and salinity fluctuations as well as how the organism persists under constant predation by heterotrophic protists. PMID:24379807

  3. Antagonistic association of the chlorellavorus bacterium ( “Bdellovibrio” chlorellavorus ) with Chlorella vulgaris

    Microsoft Academic Search

    David M. Coder; Mortimer P. Starr

    1978-01-01

    The chlorellavorus bacterium (Bdellovibrio chlorellavorus Gromov and Mamkaeva 1972) attaches to (but does not enter) cells of the unicellular green alga,Chlorella, which is killed and the cell contents of which are digested. The bacterium is pleomorphic (vibrios 0.3 ?m wide; cocci 0.6\\u000a ?m wide), and it has a Gram-negative cell wall structure pili, and a single, unsheathed, polar flagellum. Division

  4. Temperature regulation of virulence factors in the pathogen Vibrio coralliilyticus

    PubMed Central

    Kimes, Nikole E; Grim, Christopher J; Johnson, Wesley R; Hasan, Nur A; Tall, Ben D; Kothary, Mahendra H; Kiss, Hajnalka; Munk, A Christine; Tapia, Roxanne; Green, Lance; Detter, Chris; Bruce, David C; Brettin, Thomas S; Colwell, Rita R; Morris, Pamela J

    2012-01-01

    Sea surface temperatures (SST) are rising because of global climate change. As a result, pathogenic Vibrio species that infect humans and marine organisms during warmer summer months are of growing concern. Coral reefs, in particular, are already experiencing unprecedented degradation worldwide due in part to infectious disease outbreaks and bleaching episodes that are exacerbated by increasing SST. For example, Vibrio coralliilyticus, a globally distributed bacterium associated with multiple coral diseases, infects corals at temperatures above 27?°C. The mechanisms underlying this temperature-dependent pathogenicity, however, are unknown. In this study, we identify potential virulence mechanisms using whole genome sequencing of V. coralliilyticus ATCC (American Type Culture Collection) BAA-450. Furthermore, we demonstrate direct temperature regulation of numerous virulence factors using proteomic analysis and bioassays. Virulence factors involved in motility, host degradation, secretion, antimicrobial resistance and transcriptional regulation are upregulated at the higher virulent temperature of 27?°C, concurrent with phenotypic changes in motility, antibiotic resistance, hemolysis, cytotoxicity and bioluminescence. These results provide evidence that temperature regulates multiple virulence mechanisms in V. coralliilyticus, independent of abundance. The ecological and biological significance of this temperature-dependent virulence response is reinforced by climate change models that predict tropical SST to consistently exceed 27?°C during the spring, summer and fall seasons. We propose V. coralliilyticus as a model Gram-negative bacterium to study temperature-dependent pathogenicity in Vibrio-related diseases. PMID:22158392

  5. Biodiversity of Vibrios

    PubMed Central

    Thompson, Fabiano L.; Iida, Tetsuya; Swings, Jean

    2004-01-01

    Vibrios are ubiquitous and abundant in the aquatic environment. A high abundance of vibrios is also detected in tissues and/or organs of various marine algae and animals, e.g., abalones, bivalves, corals, fish, shrimp, sponges, squid, and zooplankton. Vibrios harbour a wealth of diverse genomes as revealed by different genomic techniques including amplified fragment length polymorphism, multilocus sequence typing, repetetive extragenic palindrome PCR, ribotyping, and whole-genome sequencing. The 74 species of this group are distributed among four different families, i.e., Enterovibrionaceae, Photobacteriaceae, Salinivibrionaceae, and Vibrionaceae. Two new genera, i.e., Enterovibrio norvegicus and Grimontia hollisae, and 20 novel species, i.e., Enterovibrio coralii, Photobacterium eurosenbergii, V. brasiliensis, V. chagasii, V. coralliillyticus, V. crassostreae, V. fortis, V. gallicus, V. hepatarius, V. hispanicus, V. kanaloaei, V. neonatus, V. neptunius, V. pomeroyi, V. pacinii, V. rotiferianus, V. superstes, V. tasmaniensis, V. ezurae, and V. xuii, have been described in the last few years. Comparative genome analyses have already revealed a variety of genomic events, including mutations, chromosomal rearrangements, loss of genes by decay or deletion, and gene acquisitions through duplication or horizontal transfer (e.g., in the acquisition of bacteriophages, pathogenicity islands, and super-integrons), that are probably important driving forces in the evolution and speciation of vibrios. Whole-genome sequencing and comparative genomics through the application of, e.g., microarrays will facilitate the investigation of the gene repertoire at the species level. Based on such new genomic information, the taxonomy and the species concept for vibrios will be reviewed in the next years. PMID:15353563

  6. Phylogeny of the coral pathogen Vibrio coralliilyticus.

    PubMed

    Pollock, F Joseph; Wilson, Bryan; Johnson, Wesley R; Morris, Pamela J; Willis, Bette L; Bourne, David G

    2010-02-01

    A phenotypic and phylogenetic comparison of geographically disparate isolates of the coral pathogen Vibrio coralliilyticus was conducted to determine whether the bacterium exists as a single cosmopolitan clonal population, which might indicate rapid spread of a pandemic strain, or is grouped into endemic and genotypically distinct strains. All strains included in this study displayed similar phenotypic characteristics to those of the typed V. coralliilyticus strain LMG 20984(T) . Five phylogenetic marker genes (16S, rpoA, recA, pyrH and dnaJ) frequently used for discriminating closely related Vibrio species and a zinc-metalloprotease gene (vcpA) linked to pathogenicity were sequenced in 13?V. coralliilyticus isolates collected from corals, bivalves, and their surrounding seawater in the Red and Caribbean Seas, and Indian, Pacific and Atlantic Oceans. A high level of genetic polymorphism was observed with all isolates possessing unique genotypes at all six genetic loci examined. No consistent lineage structure was observed within the marker genes and homologous recombination was detected in the 16S and vcpA genes, suggesting that V. coralliilyticus does not possess a highly clonal population structure. Interestingly, two geographically distinct (Caribbean/south-Atlantic and Indo-Pacific/north-Atlantic) and highly divergent clades were detected within the zinc-metalloprotease gene, but it is not known if these clades correspond to phenotypic differences in virulence. These findings stress the need for a multi-locus approach for inferring V. coralliilyticus phylogeny and indicate that populations of this bacterium are likely an endemic component of coral reef ecosystems globally. PMID:23766013

  7. A K+ Uptake Protein, TrkA, Is Required for Serum, Protamine, and Polymyxin B Resistance in Vibrio vulnificus

    Microsoft Academic Search

    Yu-Chung Chen; Yin-Ching Chuang; Chun-Chin Chang; Chii-Ling Jeang; Ming-Chung Chang

    2004-01-01

    Vibrio vulnificus, a highly virulent marine bacterium, is the causative agent of both serious wound infections and fatal septicemia in many areas of the world. To identify the genes required for resistance to human serum, we constructed a library of transposon mutants of V. vulnificus and screened them for hypersensitivity to human serum. Here we report that one of the

  8. Sequence Analysis of the beta-N-Acetylhexosaminidase Gene of Vibrio vulnificus: Evidence for a Common Evolutionary Origin of Hexosaminidases

    Microsoft Academic Search

    Charles C. Somerville; Rita R. Colwell

    1993-01-01

    DNA cloned from the marine bacterium Vibrio vulnificus into Escherichia coli HB101 can hydrolyze chitin oligomer analogs in the recipient. The nucleotide sequence of the cloned DNA was determined and a single long open reading frame of 2541 base pairs (initiation codon through termination codon) was found. The nucleotide sequence predicts a gene product of 847 amino acids and a

  9. Identification and Characterization of a Vibrio cholerae Gene, mbaA, Involved in Maintenance of Biofilm Architecture

    Microsoft Academic Search

    Natalia Bomchil; Paula Watnick; Roberto Kolter

    2003-01-01

    The formation of biofilms is thought to play a key role in the environmental survival of the marine bacterium Vibrio cholerae. Although the factors involved in V. cholerae attachment to abiotic surfaces have been extensively studied, relatively little is known about the mechanisms involved in the subsequent maturation of the biofilms. Here we report the identification of a novel gene,

  10. RNA Colony Blot Hybridization Method for Enumeration of Culturable Vibrio cholerae and Vibrio mimicus Bacteria?

    PubMed Central

    Grim, Christopher J.; Zo, Young-Gun; Hasan, Nur A.; Ali, Afsar; Chowdhury, Wasimul B.; Islam, Atiqul; Rashid, Mohammed H.; Alam, Munirul; Morris, J. Glenn; Huq, Anwar; Colwell, Rita R.

    2009-01-01

    A species-specific RNA colony blot hybridization protocol was developed for enumeration of culturable Vibrio cholerae and Vibrio mimicus bacteria in environmental water samples. Bacterial colonies on selective or nonselective plates were lysed by sodium dodecyl sulfate, and the lysates were immobilized on nylon membranes. A fluorescently labeled oligonucleotide probe targeting a phylogenetic signature sequence of 16S rRNA of V. cholerae and V. mimicus was hybridized to rRNA molecules immobilized on the nylon colony lift blots. The protocol produced strong positive signals for all colonies of the 15 diverse V. cholerae-V. mimicus strains tested, indicating 100% sensitivity of the probe for the targeted species. For visible colonies of 10 nontarget species, the specificity of the probe was calculated to be 90% because of a weak positive signal produced by Grimontia (Vibrio) hollisae, a marine bacterium. When both the sensitivity and specificity of the assay were evaluated using lake water samples amended with a bioluminescent V. cholerae strain, no false-negative or false-positive results were found, indicating 100% sensitivity and specificity for culturable bacterial populations in freshwater samples when G. hollisae was not present. When the protocol was applied to laboratory microcosms containing V. cholerae attached to live copepods, copepods were found to carry approximately 10,000 to 50,000 CFU of V. cholerae per copepod. The protocol was also used to analyze pond water samples collected in an area of cholera endemicity in Bangladesh over a 9-month period. Water samples collected from six ponds demonstrated a peak in abundance of total culturable V. cholerae bacteria 1 to 2 months prior to observed increases in pathogenic V. cholerae and in clinical cases recorded by the area health clinic. The method provides a highly specific and sensitive tool for monitoring the dynamics of V. cholerae in the environment. The RNA blot hybridization protocol can also be applied to detection of other gram-negative bacteria for taxon-specific enumeration. PMID:19561182

  11. Mortalities of Eastern and Pacific oyster Larvae caused by the pathogens Vibrio coralliilyticus and Vibrio tubiashii.

    PubMed

    Richards, Gary P; Watson, Michael A; Needleman, David S; Church, Karlee M; Häse, Claudia C

    2015-01-01

    Vibrio tubiashii is reported to be a bacterial pathogen of larval Eastern oysters (Crassostrea virginica) and Pacific oysters (Crassostrea gigas) and has been associated with major hatchery crashes, causing shortages in seed oysters for commercial shellfish producers. Another bacterium, Vibrio coralliilyticus, a well-known coral pathogen, has recently been shown to elicit mortality in fish and shellfish. Several strains of V. coralliilyticus, such as ATCC 19105 and Pacific isolates RE22 and RE98, were misidentified as V. tubiashii until recently. We compared the mortalities caused by two V. tubiashii and four V. coralliilyticus strains in Eastern and Pacific oyster larvae. The 50% lethal dose (LD50) of V. coralliilyticus in Eastern oysters (defined here as the dose required to kill 50% of the population in 6 days) ranged from 1.1 × 10(4) to 3.0 × 10(4) CFU/ml seawater; strains RE98 and RE22 were the most virulent. This study shows that V. coralliilyticus causes mortality in Eastern oyster larvae. Results for Pacific oysters were similar, with LD50s between 1.2 × 10(4) and 4.0 × 10(4) CFU/ml. Vibrio tubiashii ATCC 19106 and ATCC 19109 were highly infectious toward Eastern oyster larvae but were essentially nonpathogenic toward healthy Pacific oyster larvae at dosages of ?1.1 × 10(4) CFU/ml. These data, coupled with the fact that several isolates originally thought to be V. tubiashii are actually V. coralliilyticus, suggest that V. coralliilyticus has been a more significant pathogen for larval bivalve shellfish than V. tubiashii, particularly on the U.S. West Coast, contributing to substantial hatchery-associated morbidity and mortality in recent years. PMID:25344234

  12. [Septic shock by Vibrio vulnificus at the coast Gulf of Mexico].

    PubMed

    Baizabal-Ramírez, Oscar; Negrete-Pérez, Mónica; Guerrero-Daza, Damayanty; Martínez-Herrera, Nahum; Aburto-Desachy, Yolanda; Mata-Miranda, Pilar

    2011-01-01

    Vibrio vulnificus is a Gram-negative bacterium which is found in marine environments and where there is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea. The infection by these bacteria can cause primary septicemia by two mechanisms: upon consuming crustaceans, mollusks and some fish (filtering shellfish) raw or barely cooked or by an open injury in contact with seawater. The patients with infections of the primary injury by Vibrio vulnificus developed contaminated painful cellulitis that progresses quickly as well as a marked local inflammation with signs of hemorrhaging. We described a case of Vibrio vulnificus sepsis, with emphasis on the clinical picture, the epidemiological background and lab findings; finally we did a brief review of the literature related to the case. PMID:21982195

  13. [Identification of Vibrio campbellii isolated from cultured pacific oyster].

    PubMed

    Shen, Xiao-sheng; Cai, You-qiong; Fang, Wen-hong; Gu, Run-run; Gao, Dan-feng

    2005-04-01

    Four bacterial strains were isolated from cultured pacific oyster (Crassostrea gigia) in September 2003 at coast of Fujian province. Their morphological, physiological and biochemical characteristics and 16S rRNA sequence were analyzed. And the relationship between reproduction of the bacterium and NaCl concentrations, pH and temperature were also determined. The results showed that four strains were gram-negative rods with a single polar flagellum, glucose fermented without gas production, oxidase positive, required sodium ions for growth, no pigment, non-luminescence; They grew well on TCBS-plate as green colonies and were sensitive to the vibriostratic agent O/129. Therefore, it was confirmed that the strains belonged to the genus of Vibrio. The sequence analysis of 16S rRNA gene of SXS1 isolation and comparison with that of other related vibrios- showed that SXS1 was very close to Vibrio campbellii. The similarities was 99%. The distribution of V. campbellii in environment and its relationship to the diseases of aquaculture animals were discussed. PMID:15989255

  14. Draft Genome Sequences of Vibrio fluvialis Strains 560 and 539, Isolated from Environmental Samples

    PubMed Central

    de Oliveira Veras, Adonney Allan; da Silva, Miriam Lopes; Gomes, Jaqueline Conceição Meireles; Dias, Larissa Maranhão; de Sá, Pablo Caracciolo Gomes; Alves, Jorianne Thyeska Castro; Castro, Wendel; Miranda, Fábio; Kazuo, Ehilton; Marinho, Diogo; Rodrigues, Mateus; Freire, Matheus; Zahlouth, Ramiro; Renan, Wendel; Lopes, Thiago Souza; Matté, Maria Helena; da Silva Mayer, Cintia Carolina; de Almeida Vasconcelos Barboni, Suzi; Matté, Glavur Rogério; Carneiro, Adriana Ribeiro; Silva, Artur

    2015-01-01

    Vibrio fluvialis is a halophilic bacterium found in many environments and is mainly associated with sporadic cases and outbreaks of gastroenteritis in humans. Here, we describe the genome sequences of environmental strains of V. fluvialis 560 (Vf560) and V. fluvialis 539 (Vf539) possessing a variant of the integrative and conjugative element (ICE) SXT for the first time in Brazil and South America. PMID:25573928

  15. Identification of Vibrio parahaemolyticus Pandemic Group-Specific DNA Sequence by Genomic Subtraction

    Microsoft Academic Search

    Masatoshi Okura; Ro Osawa; Eiji Arakawa; Jun Terajima; Haruo Watanabe

    2005-01-01

    Vibrio parahaemolyticus is a major cause of seafood-borne gastroenteritis, frequently associated with the consumption of raw or undercooked seafood (2). Although various serovars of the bacterium can cause infections, O3:K6, O4:K68, and sev- eral other serovars producing thermostable direct hemolysin (TDH) have been recognized as the predominant group re- sponsible for most outbreaks occurring worldwide since 1996 (6, 8). Past

  16. Inhibition of Vibrio anguillarum by Pseudomonas fluorescens AH2, a Possible Probiotic Treatment of Fish

    Microsoft Academic Search

    LONE GRAM; JETTE MELCHIORSEN; BETTINA SPANGGAARD; INGRID HUBER; TORBEN F. NIELSEN

    1999-01-01

    To study the possible use of probiotics in fish farming, we evaluated the in vitro and in vivo antagonism of antibacterial strain Pseudomonas fluorescens strain AH2 against the fish-pathogenic bacterium Vibrio anguil- larum. As iron is important in virulence and bacterial interactions, the effect of P. fluorescens AH2 was studied under iron-rich and iron-limited conditions. Sterile-filtered culture supernatants from iron-limited

  17. Detection of Vibrio (Listonella) Anguillarum Porin Homologue Proteins and Their Source Bacteria from Coastal Seawater

    Microsoft Academic Search

    Namiha Yamada; Satoru Suzuki; Eiichiro Tanoue

    2000-01-01

    The molecular distribution of dissolved proteins in seawater from coastal marine environments in Uranouchi Bay, Kochi Prefecture, is first reported in this article. Occurrence of bacteria-derived dissolved proteins and their source bacteria were examined using a probe of the antibody (anti-Omp35La) against a porin outer membrane protein (Omp35La) of the fish pathogenic bacterium Vibrio (Listonella) anguillarum. The electrophoretograms of dissolved

  18. Detection of Vibrio (Listonella) anguillarum Porin Homologue Proteins and Their Source Bacteria from Coastal Seawater

    Microsoft Academic Search

    NAMIHA YAMADA; SATORU SUZUKI; EIICHIRO TANOUE

    2000-01-01

    The molecular distribution of dissolved proteins in seawater from coastal marine en- vironments in Uranouchi Bay, Kochi Prefecture, is first reported in this article. Oc- currence of bacteria-derived dissolved proteins and their source bacteria were exam- ined using a probe of the antibody (anti-Omp35La) against a porin outer membrane protein (Omp35La) of the fish pathogenic bacterium Vibrio (Listonella) anguillarum. The

  19. Growth and flagellation of Vibrio fischeri during initiation of the sepiolid squid light organ symbiosis

    Microsoft Academic Search

    E. G. Ruby; L. M. Asato

    1993-01-01

    A pure culture of the luminous bacterium Vibrio fischeri is maintained in the light-emitting organ of the sepiolid squid Euprymna scolopes. When the juvenile squid emerges from its egg it is symbiont-free and, because bioluminescence is part of an anti-predatory behavior, therefore must obtain a bacterial inoculum from the surrounding environment. We document here the kinetics of the process by

  20. Autecology of Vibrio vulnificus and Vibrio parahaemolyticus in tropical waters

    SciTech Connect

    Rivera, S.; Lugo, T.; Hazen, T.C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico)

    1988-12-31

    Water and shellfish samples collected from estuaries, mangroves, and beaches along the coast of Puerto Rico were examined for Vibrio vulnificus and Vibrio parahaemolyticus. An array of water quality parameters were also measured simultaneous with bacteria sampling. Both species of vibrio were associated with estuary and mangrove locations, and neither was isolated from sandy beaches. Densities of V. vulnificus were negatively correlated with salinity, 10--15 ppt being optimal. V. parahaemolyticus was isolated from sites with salinities between 20 and 35 ppt, the highest densities occurring at 20 ppt. Densities of Vibrio spp. and V. parahaemolyticus for a tropical estuary surpassed those reported for temperate estuaries by several orders of magnitude. Both densities of total Vibrio spp. and V. parahaemolyticus in the water were directly related to densities of fecal coliforms, unlike V. vulnificus. The incidence of ONPG(+) strains among sucrose({minus}) Vibrio spp. served as an indicator of the frequency of V. vulnificus in this group. More than 63% of the V. vulnificus isolated were pathogenic. V. vulnificus and V. parahaemolyticus occupy clearly separate niches within the tropical estuarine-marine ecosystem.

  1. Vibrio chromosomes share common history

    E-print Network

    Kirkup, Benjamin C.

    Abstract Background While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it ...

  2. Vibrio chromosomes share common history

    E-print Network

    Kirkup, Benjamin C.

    Background: While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it is an ...

  3. Characterization of Undermethylated Sites in Vibrio cholerae

    PubMed Central

    Dalia, Ankur B.; Lazinski, David W.

    2013-01-01

    The activities of DNA methyltransferases are important for a variety of cellular functions in bacteria. In this study, we developed a modified high-throughput technique called methyl homopolymer tail mediated sequencing (methyl HTM-seq) to identify the undermethylated sites in the Vibrio cholerae genome for the two DNA methyltransferases, Dam, an adenine methyltransferase, and VchM, a cytosine methyltransferase, during growth in rich medium in vitro. Many of the undermethylated sites occurred in intergenic regions, and for most of these sites, we identified the transcription factors responsible for undermethylation. This confirmed the presence of previously hypothesized DNA-protein interactions for these transcription factors and provided insight into the biological state of these cells during growth in vitro. DNA adenine methylation has previously been shown to mediate heritable epigenetic switches in gene regulation. However, none of the undermethylated Dam sites tested showed evidence of regulation by this mechanism. This study is the first to identify undermethylated adenines and cytosines genomewide in a bacterium using second-generation sequencing technology. PMID:23504020

  4. Surface-attachment sequence in Vibrio Cholerae

    NASA Astrophysics Data System (ADS)

    Utada, Andrew; Gibiansky, Maxsim; Wong, Gerard

    2013-03-01

    Vibrio cholerae is a gram-negative bacterium that causes the human disease cholera. It is found natively in brackish costal waters in temperate climates, where it attaches to the surfaces of a variety of different aquatic life. V. cholerae has a single polar flagellum making it highly motile, as well as a number of different pili types, enabling it to attach to both biotic and abiotic surfaces. Using in-house built tracking software we track all surface-attaching bacteria from high-speed movies to examine the early-time attachment profile of v. cholerae onto a smooth glass surface. Similar to previous work,footnotetextLauga, E., DiLuzio, W. R., Whitesides, G. M., Stone, H. A. Biophys. J. 90, 400 (2006). we observe right-handed circular swimming trajectories near surfaces; however, in addition we see a host of distinct motility mechanisms that enable rapid exploration of the surface before forming a more permanent attachment. Using isogenic mutants we show that the motility mechanisms observed are due to a complex combination of hydrodynamics and pili-surface interactions.

  5. Development of Vibrio spp. infection resistance related SNP markers using multiplex SNaPshot genotyping method in the clam Meretrix meretrix.

    PubMed

    Nie, Qing; Yue, Xin; Liu, Baozhong

    2015-04-01

    The clam Meretrix meretrix is a commercially important mollusc species in the coastal areas of South and Southeast Asia. In the present study, large-scale SNPs were genotyped by the Multiplex SNaPshot genotyping method among the stocks of M. meretrix with different Vibrio spp. infection resistance profile. Firstly, the AUTOSNP software was applied to mine SNPs from M. meretrix transcriptome, and 323 SNP loci (including 120 indels) located on 64 contigs were selected based on Uniprot-GO associations. Then, 38 polymorphic SNP loci located on 15 contigs were genotyped successfully in the clam stocks with different resistance to Vibrio parahaemolyticus infection (11-R and 11-S groups). Pearson's Chi-square test was applied to compare the allele and genotype frequency distributions of the SNPs between the different stocks, and seven SNP markers located on three contigs were found to be associated with V. parahaemolyticus infection resistance trait. Haplotype-association analysis showed that six haplotypes had significantly different frequency distributions in 11-S and 11-R (P < 0.05). With selective genotyping between 09-R and 09-C populations, which had different resistance to Vibrio harveyi infection, four out of the seven selected SNPs had significantly different distributions (P < 0.05) and therefore they were considered to be associated with Vibrio spp. infection resistance. Sequence alignments and annotations indicated that the contigs containing the associated SNPs had high similarity to the immune related genes. All these results would be useful for the future marker-assisted selection of M. meretrix strains with high Vibrio spp. infection resistance. PMID:25655323

  6. Comparison of the use of mussels and semipermeable membrane devices for monitoring and assessment of accumulation of mutagenic pollutants in marine environment in combination with a novel microbiological mutagenicity assay

    Microsoft Academic Search

    Ewa Ch??; Beata Podgórska; Grzegorz W?grzyn

    2008-01-01

    A novel microbiological mutagenicity assay, based on bioluminescence of a marine bacterium Vibrio harveyi mutant strain, potentially suitable for monitoring and assessment of mutagenic pollution of marine environment, has been\\u000a described recently. Here, we tested the use of this assay, in combination with either mussels (Mytilus sp.) or semipermeable membrane devices (SPMDs), in assessment of accumulation of mutagens in marine

  7. Vibrio splendidus biovar II as the causative agent of bacillary necrosis of Japanese oyster Crassostrea gigas larvae.

    PubMed

    Sugumar, G; Nakai, T; Hirata, Y; Matsubara, D; Muroga, K

    1998-06-19

    Recurrent outbreaks of a disease leading to mass mortalities in an oyster (Crassostrea gigas) hatchery located in western Japan were investigated. The disease occurred regularly in 2- to 8-d-old larvae and has been experimentally controlled in the hatchery by treating the larval rearing water with streptomycin, without ascertaining the etiological agent. The signs of the disease and the course of infection resembled bacillary necrosis reported in oysters and other bivalve molluscs in the USA and Europe. Quantitative and qualitative examinations of the bacterial flora of hatchery samples including source water, broodstock, larval feed and larvae revealed a very high total bacterial load and presumptive vibrios in diseased larvae. Further, the bacterial profile revealed that Vibrio spp. constituted approximately 60 to 95% of the bacteria isolated from infected larvae and most isolates were identified as V. splendidus biovar II and V. harveyi, suggesting their possible role in the disease. However, experimental challenges proved the pathogenicity of V. splendidus II. Several isolates of V. splendidus II from infected larvae were highly pathogenic, producing 100% mortality at levels of 10(5) cfu ml-1 in 24 h, while isolates from other sources demonstrated a low degree of virulence. Detection of V. splendidus II from broodstock, especially in the gonad of a few breeders, suggests the probability that broodstock could be the source and route of transmission of this pathogen. PMID:9684317

  8. Assessing single and joint toxicity of three phenylurea herbicides using Lemna minor and Vibrio fischeri bioassays.

    PubMed

    Gatidou, Georgia; Stasinakis, Athanasios S; Iatrou, Evangelia I

    2015-01-01

    Single and joint toxicity of three substituted urea herbicides, namely monolinuron [3-(4-chlorophenyl)-1-methoxy-1-methylurea], linuron [3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea] and diuron [1-(3,4 dichlorophenyl)-3,3 dimethyl urea], were studied. The duckweed Lemna minor and the luminescent bacterium Vibrio fischeri were used for the toxicity assessment and they were exposed to various concentrations of the herbicides, individually and in binary mixtures. The exposure time was 7d for the duckweed and 30 min for the bacterium. Estimation of EC50 values was performed by frond counting and reduction in light output for Lemna minor and Vibrio fischeri, respectively. Lemna minor was found to be much more sensitive than Vibrio fischeri to target compounds. The toxicity of the three herbicides applied solely was estimated to be in decreasing order: diuron (EC50=28.3 ?g L(-1))?linuron (EC50=30.5 ?g L(-1))>monolinuron (EC50=300 ?g L(-1)) for the duckweed and linuron (EC50=8.2 mg L(-1))>diuron (EC50=9.2 mg L(-1))>monolinuron (EC50=11.2 mg L(-1)) for the bacterium. Based on the environmental concentrations reported in the literature and EC50 values obtained from Lemna minor experiments, Risk Quotients (RQ) much higher than 1 were calculated for diuron and linuron. In Lemna minor experiments, combination of target compounds resulted to additive effects due to their same mode of phenylurea action on photosynthetic organisms. Regarding Vibrio fischeri, synergistic, additive and antagonistic effects were observed, which varied according to the concentrations of target compounds. PMID:24821233

  9. Vibrio parahaemolyticus: a review on the pathogenesis, prevalence, and advance molecular identification techniques

    PubMed Central

    Letchumanan, Vengadesh; Chan, Kok-Gan; Lee, Learn-Han

    2014-01-01

    Vibrio parahaemolyticus is a Gram-negative halophilic bacterium that is found in estuarine, marine and coastal environments. V. parahaemolyticus is the leading causal agent of human acute gastroenteritis following the consumption of raw, undercooked, or mishandled marine products. In rare cases, V. parahaemolyticus causes wound infection, ear infection or septicaemia in individuals with pre-existing medical conditions. V. parahaemolyticus has two hemolysins virulence factors that are thermostable direct hemolysin (tdh)-a pore-forming protein that contributes to the invasiveness of the bacterium in humans, and TDH-related hemolysin (trh), which plays a similar role as tdh in the disease pathogenesis. In addition, the bacterium is also encodes for adhesions and type III secretion systems (T3SS1 and T3SS2) to ensure its survival in the environment. This review aims at discussing the V. parahaemolyticus growth and characteristics, pathogenesis, prevalence and advances in molecular identification techniques. PMID:25566219

  10. Ethanolamine utilization in Vibrio alginolyticus

    PubMed Central

    2012-01-01

    Abstract Ethanolamine is used as an energy source by phylogenetically diverse bacteria including pathogens, by the concerted action of proteins from the eut-operon. Previous studies have revealed the presence of eutBC genes encoding ethanolamine-ammonia lyase, a key enzyme that breaks ethanolamine into acetaldehyde and ammonia, in about 100 bacterial genomes including members of gamma-proteobacteria. However, ethanolamine utilization has not been reported for any member of the Vibrio genus. Our comparative genomics study reveals the presence of genes that are involved in ethanolamine utilization in several Vibrio species. Using Vibrio alginolyticus as a model system we demonstrate that ethanolamine is better utilized as a nitrogen source than as a carbon source. Reviewers This article was reviewed by Dr. Lakshminarayan Iyer and Dr. Vivek Anantharaman (nominated by Dr. L Aravind). PMID:23234435

  11. Genomics of Pathogenic Vibrio Species

    NASA Astrophysics Data System (ADS)

    Dziejman, Michelle; Yildiz, Fitnat H.

    Members of the heterotrophic bacterial family Vibrionaceae are native inhabitants of aquatic environments worldwide, constituting a diverse and abundant component of marine microbial organisms. Over 60 species of the genus Vibrio have been identified (Thompson et al., 2004) and their phenotypic heterogeneity is well documented. The ecology of the genus remains less well understood, however, despite reports that vibrios are the dominant microorganisms inhabiting the superficial water layer and colonizing the chitinous exoskeleton of zooplankton (e.g., copepods, Thompson et al., 2004). Although some species were originally isolated from seawater as free living organisms, most were isolated in association with marine life such as bivalves, fish, eels, or shrimp.

  12. The Outer Surface Lipoprotein VolA Mediates Utilization of Exogenous Lipids by Vibrio cholerae

    PubMed Central

    Pride, Aaron C.; Herrera, Carmen M.; Guan, Ziqiang; Giles, David K.; Trent, M. Stephen

    2013-01-01

    ABSTRACT Previous work from our laboratory showed that the Gram-negative aquatic pathogen Vibrio cholerae can take up a much wider repertoire of fatty acids than other Gram-negative organisms. The current work elaborated on the ability of V. cholerae to exploit an even more diverse pool of lipid nutrients from its environment. We have demonstrated that the bacterium can use lysophosphatidylcholine as a metabolite for growth. Using a combination of thin-layer chromatography and mass spectrometry, we also showed that lysophosphatidylcholine-derived fatty acid moieties can be used for remodeling the V. cholerae membrane architecture. Furthermore, we have identified a lysophospholipase, VolA (Vibrio outer membrane lysophospholipase A), required for these activities. The enzyme is well conserved in Vibrio species, is coexpressed with the outer membrane fatty acid transporter FadL, is one of very few surface-exposed lipoprotein enzymes to be identified in Gram-negative bacteria and the first instance of a surface lipoprotein phospholipase. We propose a model whereby the bacterium efficiently couples the liberation of fatty acid from lysophosphatidylcholine to its subsequent metabolic uptake. An expanded ability to scavenge diverse environmental lipids at the bacterial surface increases overall bacterial fitness and promotes homeoviscous adaptation through membrane remodeling. PMID:23674613

  13. Endophthalmitis Caused by Vibrio alginolyticus?

    PubMed Central

    Li, Xiao Chun; Xiang, Zhen Yang; Xu, Xiao Ming; Yan, Wei Hua; Ma, Jian Min

    2009-01-01

    Vibrio alginolyticus is a facultative anaerobic gram-negative bacillus found in normal marine flora. Ocular infections induced by V. alginolyticus are extremely rare. We report a case of endophthalmitis caused by V. alginolyticus to draw attention to V. alginolyticus infections following ocular injuries. PMID:19710275

  14. VIBRIO VULNIFICUS EDUCATION WORKSHOPS / MATERIALS

    EPA Science Inventory

    This project will promote Vibrio vulnificus education on-line continuing medical education units to health care professionals that counsel and care for at-risk individuals. The Florida Department of Agriculture and Consumer Services will purchase advertisement and promotion in me...

  15. In situ measured elimination of Vibrio cholerae from brackish water.

    PubMed

    Pérez, María Elena Martínez; Macek, Miroslav; Galván, María Teresa Castro

    2004-01-01

    In situ elimination of fluorescently labelled Vibrio cholerae (FLB) was measured in two saline water bodies in Mexico: in a brackish water lagoon, Mecoacán (Gulf of Mexico; State of Tabasco) and an athalassohaline lake, Alchichica (State of Puebla). Disappearance rates of fluorescently labelled V. cholera O1 showed that they were eliminated from the environment at an average rate of 32% and 63%/day, respectively (based on the bacterial standing stocks). The indirect immunofluorescence method confirmed the presence of V. cholerae O1 in the lagoon. However, the elimination of FLB was not directly related either to the presence or absence of the bacterium in the water body or to the phytoplankton concentration. PMID:14728617

  16. Vibrio cholerae as a predator: lessons from evolutionary principles

    PubMed Central

    Pukatzki, Stefan; Provenzano, Daniele

    2013-01-01

    Diarrheal diseases are the second-most common cause of death among children under the age of five worldwide. Cholera alone, caused by the marine bacterium Vibrio cholerae, is responsible for several million cases and over 120,000 deaths annually. When contaminated water is ingested, V. cholerae passes through the gastric acid barrier, penetrates the mucin layer of the small intestine, and adheres to the underlying epithelial lining. V. cholerae multiplies rapidly, secretes cholera toxin, and exits the human host in vast numbers during diarrheal purges. How V. cholerae rapidly reaches such high numbers during each purge is not clearly understood. We propose that V. cholerae employs its bactericidal type VI secretion system to engage in intraspecies and intraguild predation for nutrient acquisition to support rapid growth and multiplication. PMID:24368907

  17. Detection of quorum-sensing-related molecules in Vibrio scophthalmi

    PubMed Central

    García-Aljaro, Cristina; Eberl, Leo; Riedel, Kathrin; Blanch, Anicet R

    2008-01-01

    Background Cell-to-cell communication (also referred to as quorum sensing) based on N-acyl-homoserine lactones (AHLs) is a widespread response to environmental change in Gram-negative bacteria. AHLs seem to be highly variable, both in terms of the acyl chain length and in the chemical structure of the radicals. Another quorum sensing pathway, the autoinducer-2-based system, is present both in Gram-positive and Gram-negative bacteria. In this study the presence of signal molecules belonging to both quorum sensing signalling pathways was analysed in the marine symbiotic species Vibrio scophthalmi. Results Three AHL-like signal molecules were detected in V. scophthalmi supernatants with the Agrobacterium tumefaciens sensor assay. This observation was further supported by the decrease in the presence of these signal molecules after cloning and expression of lactonase AiiA from Bacillus cereus in the V. scophthalmi strains. One of the signal molecules was identified as N-(3-hydroxy dodecanoyl)-L-homoserine lactone. V. scophthalmi was also shown to carry a functional LuxS synthase. The coding sequence for a luxS-like gene was obtained showing a maximum similarity of 78% with Vibrio vulnificus. Analysis of the translated sequence revealed that the sequenced luxS gene carried the conserved domain, which is common to luxS sequences found in other species, and which is essential for LuxS enzymatic activity. Conclusion The data are consistent with the presence of quorum-sensing signal molecules from both AHL- and autoinducer 2-based quorum sensing systems in V. scophthalmi, which are homologous to others previously described in various Vibrio species. How this bacterium interacts with other bacteria and eukaryotic cells to compete ecologically with other intestinal bacteria present in the fish Scophthalmus maximus warrants further investigation. PMID:18700048

  18. Hybrid Motor with H1- and Na1Driven Components Can Rotate Vibrio Polar Flagella by Using Sodium Ions

    Microsoft Academic Search

    YUKAKO ASAI; IKURO KAWAGISHI; R. ELIZABETH SOCKETT; MICHIO HOMMA

    The bacterial flagellar motor is a molecular machine that converts ion flux across the membrane into flagellar rotation. The coupling ion is either a proton or a sodium ion. The polar flagellar motor of the marine bacterium Vibrio alginolyticus is driven by sodium ions, and the four protein components, PomA, PomB, MotX, and MotY, are essential for motor function. Among

  19. Complete Sequence of Virulence Plasmid pJM1 from the Marine Fish Pathogen Vibrio anguillarum Strain 775

    Microsoft Academic Search

    Manuela Di Lorenzo; Michiel Stork; Marcelo E. Tolmasky; Luis A. Actis; David Farrell; Timothy J. Welch; Lidia M. Crosa; Anne M. Wertheimer; Qian Chen; Patricia Salinas; Lillian Waldbeser; Jorge H. Crosa

    2003-01-01

    The virulence plasmid pJM1 enables the fish pathogen Vibrio anguillarum, a gram-negative polarly flagel- lated comma-shaped rod bacterium, to cause a highly fatal hemorrhagic septicemic disease in salmonids and other fishes, leading to epizootics throughout the world. The pJM1 plasmid 65,009-nucleotide sequence, with an overall GC content of 42.6%, revealed genes and open reading frames (ORFs) encoding iron transporters, nonribosomal

  20. Presence of the fish pathogen Vibrio salmonicida in fish farm sediments.

    PubMed Central

    Enger, O; Husevåg, B; Goksøyr, J

    1989-01-01

    The persistence of the fish pathogen Vibrio salmonicida in fish farm sediments was studied by use of fluorescent-antibody techniques. The specificities of the monoclonal antibodies and polyclonal rabbit serum used in the study were tested against a number of Vibrio strains, including 4 isolates from intestinal tracts of healthy fish and 98 isolates from sediments. V. salmonicida was detected in sediment samples from diseased farms several months after an outbreak of the disease. The bacterium was also detected in a sediment sample from a disease-free fish farm. No V. salmonicida could be detected in sediments not influenced by fish farming. The number of positive samples was generally higher with application of rabbit serum as opposed to use of monoclonal antibodies, indicating that the rabbit serum may cross-react with other bacteria. PMID:2696427

  1. Arp2/3-independent assembly of actin by Vibrio type III effector VopL

    PubMed Central

    Liverman, Amy D. B.; Cheng, Hui-Chun; Trosky, Jennifer E.; Leung, Daisy W.; Yarbrough, Melanie L.; Burdette, Dara L.; Rosen, Michael K.; Orth, Kim

    2007-01-01

    Microbial pathogens use a variety of mechanisms to disrupt the actin cytoskeleton during infection. Vibrio parahaemolyticus (V. para) is a Gram-negative bacterium that causes gastroenteritis, and new pandemic strains are emerging throughout the world. Analysis of the V. para genome revealed a type III secretion system effector, VopL, encoding three Wiskott–Aldrich homology 2 domains that are interspersed with three proline-rich motifs. Infection of HeLa cells with V. para induces the formation of long actin fibers in a VopL-dependent manner. Transfection of VopL promotes the assembly of actin stress fibers. In vitro, recombinant VopL potently induces assembly of actin filaments that grow at their barbed ends, independent of eukaryotic factors. Vibrio VopL is predicted to be a bacterial virulence factor that disrupts actin homeostasis during an enteric infection of the host. PMID:17942696

  2. Insights into Vibrio parahaemolyticus CHN25 response to artificial gastric fluid stress by transcriptomic analysis.

    PubMed

    Sun, Xuejiao; Liu, Taigang; Peng, Xu; Chen, Lanming

    2014-01-01

    Vibrio parahaemolyticus is the causative agent of food-borne gastroenteritis disease. Once consumed, human acid gastric fluid is perhaps one of the most important environmental stresses imposed on the bacterium. Herein, for the first time, we investigated Vibrio parahaemolyticus CHN25 response to artificial gastric fluid (AGF) stress by transcriptomic analysis. The bacterium at logarithmic growth phase (LGP) displayed lower survival rates than that at stationary growth phase (SGP) under a sub-lethal acid condition (pH 4.9). Transcriptome data revealed that 11.6% of the expressed genes in Vibrio parahaemolyticus CHN25 was up-regulated in LGP cells after exposed to AGF (pH 4.9) for 30 min, including those involved in sugar transport, nitrogen metabolism, energy production and protein biosynthesis, whereas 14.0% of the genes was down-regulated, such as ATP-binding cassette (ABC) transporter and flagellar biosynthesis genes. In contrast, the AGF stress only elicited 3.4% of the genes from SGP cells, the majority of which were attenuated in expression. Moreover, the number of expressed regulator genes was also substantially reduced in SGP cells. Comparison of transcriptome profiles further revealed forty-one growth-phase independent genes in the AGF stress, however, half of which displayed distinct expression features between the two growth phases. Vibrio parahaemolyticus seemed to have evolved a number of molecular strategies for coping with the acid stress. The data here will facilitate future studies for environmental stresses and pathogenicity of the leading seafood-borne pathogen worldwide. PMID:25490137

  3. Insights into Vibrio parahaemolyticus CHN25 Response to Artificial Gastric Fluid Stress by Transcriptomic Analysis

    PubMed Central

    Sun, Xuejiao; Liu, Taigang; Peng, Xu; Chen, Lanming

    2014-01-01

    Vibrio parahaemolyticus is the causative agent of food-borne gastroenteritis disease. Once consumed, human acid gastric fluid is perhaps one of the most important environmental stresses imposed on the bacterium. Herein, for the first time, we investigated Vibrio parahaemolyticus CHN25 response to artificial gastric fluid (AGF) stress by transcriptomic analysis. The bacterium at logarithmic growth phase (LGP) displayed lower survival rates than that at stationary growth phase (SGP) under a sub-lethal acid condition (pH 4.9). Transcriptome data revealed that 11.6% of the expressed genes in Vibrio parahaemolyticus CHN25 was up-regulated in LGP cells after exposed to AGF (pH 4.9) for 30 min, including those involved in sugar transport, nitrogen metabolism, energy production and protein biosynthesis, whereas 14.0% of the genes was down-regulated, such as ATP-binding cassette (ABC) transporter and flagellar biosynthesis genes. In contrast, the AGF stress only elicited 3.4% of the genes from SGP cells, the majority of which were attenuated in expression. Moreover, the number of expressed regulator genes was also substantially reduced in SGP cells. Comparison of transcriptome profiles further revealed forty-one growth-phase independent genes in the AGF stress, however, half of which displayed distinct expression features between the two growth phases. Vibrio parahaemolyticus seemed to have evolved a number of molecular strategies for coping with the acid stress. The data here will facilitate future studies for environmental stresses and pathogenicity of the leading seafood-borne pathogen worldwide. PMID:25490137

  4. Ocean acidification alleviates low-temperature effects on growth and photosynthesis of the red alga Neosiphonia harveyi (Rhodophyta).

    PubMed

    Olischläger, Mark; Wiencke, Christian

    2013-12-01

    This study aimed to examine interactive effects between ocean acidification and temperature on the photosynthetic and growth performance of Neosiphonia harveyi. N. harveyi was cultivated at 10 and 17.5 °C at present (~380 µatm), expected future (~800 µatm), and high (~1500 µatm) pCO2. Chlorophyll a fluorescence, net photosynthesis, and growth were measured. The state of the carbon-concentrating mechanism (CCM) was examined by pH-drift experiments (with algae cultivated at 10 °C only) using ethoxyzolamide, an inhibitor of external and internal carbonic anhydrases (exCA and intCA, respectively). Furthermore, the inhibitory effect of acetazolamide (an inhibitor of exCA) and Tris (an inhibitor of the acidification of the diffusive boundary layer) on net photosynthesis was measured at both temperatures. Temperature affected photosynthesis (in terms of photosynthetic efficiency, light saturation point, and net photosynthesis) and growth at present pCO2, but these effects decreased with increasing pCO2. The relevance of the CCM decreased at 10 °C. A pCO2 effect on the CCM could only be shown if intCA and exCA were inhibited. The experiments demonstrate for the first time interactions between ocean acidification and temperature on the performance of a non-calcifying macroalga and show that the effects of low temperature on photosynthesis can be alleviated by increasing pCO2. The findings indicate that the carbon acquisition mediated by exCA and acidification of the diffusive boundary layer decrease at low temperatures but are not affected by the cultivation level of pCO2, whereas the activity of intCA is affected by pCO2. Ecologically, the findings suggest that ocean acidification might affect the biogeographical distribution of N. harveyi. PMID:24127518

  5. Phage therapy treatment of the coral pathogen Vibrio coralliilyticus

    PubMed Central

    Cohen, Yossi; Joseph Pollock, F; Rosenberg, Eugene; Bourne, David G

    2013-01-01

    Vibrio coralliilyticus is an important coral pathogen demonstrated to cause disease outbreaks worldwide. This study investigated the feasibility of applying bacteriophage therapy to treat the coral pathogen V. coralliilyticus. A specific bacteriophage for V. coralliilyticus strain P1 (LMG23696), referred to here as bacteriophage YC, was isolated from the seawater above corals at Nelly Bay, Magnetic Island, central Great Barrier Reef (GBR), the same location where the bacterium was first isolated. Bacteriophage YC was shown to be a lytic phage belonging to the Myoviridae family, with a rapid replication rate, high burst size, and high affinity to its host. By infecting its host bacterium, bacteriophage YC was able to prevent bacterial-induced photosystem inhibition in pure cultures of Symbiodinium, the photosymbiont partner of coral and a target for virulence factors produced by the bacterial pathogen. Phage therapy experiments using coral juveniles in microtiter plates as a model system revealed that bacteriophage YC was able to prevent V. coralliilyticus-induced photoinactivation and tissue lysis. These results demonstrate that bacteriophage YC has the potential to treat coral disease outbreaks caused by the bacterial pathogen V. coralliilyticus, making it a good candidate for phage therapy treatment of coral disease. PMID:23239510

  6. Isolation and identification among cockle isolates of Vibrio vulnificus isolated from Selangor, Malaysia

    NASA Astrophysics Data System (ADS)

    Kurdi Al-Dulaimi, Mohammed M.; Mutalib, Sahilah Abd.; Ghani, Ma`aruf Abd.

    2014-09-01

    Vibrio vulnificus infections are worldwide public health problems associated with illnesses resulting from consumption of raw or partially cooked seafood. The aim of this study was to investigate the presence and identification of V. vulnificus in cockles from local wet (40) and supermarkets (38) from Selangor, Malaysia from July 2013 to February 2014. A total of 78(n=78) cockle were examined for the presence of V. vulnificus and at about 32% (25/78) cockle samples were positive to this bacterium. Colonies morphological observation and biochemical characterization for those isolates showed 60% (15/78) of isolates were classified as biotype 1 and 40% (10/78) belong to biotype 2.

  7. Microbiological and other hazards from seafoods with special reference to Vibrio parahaemolyticus

    PubMed Central

    Barrow, G. I.

    1974-01-01

    The salient features of some of the more important microbiological health hazards to man from seafoods are reviewed briefly. They include poisoning, indirectly from toxins produced by certain marine algae or more directly by Clostridium botulinum, as well as infection with the marine bacterium Vibrio parahaemolyticus. Local culinary habits play a significant role in such kinds of illness, and food well cooked shortly before consumption is always preferable. Since established customs die hard, safety ultimately depends, not so much on arbitrary microbiological standards, but on hygienic production, correct storage and distribution, and on education in intelligent eating habits. PMID:4467856

  8. Non-Lethal Heat Shock Increased Hsp70 and Immune Protein Transcripts but Not Vibrio Tolerance in the White-Leg Shrimp

    PubMed Central

    Loc, Nguyen Hong; MacRae, Thomas H.; Musa, Najiah; Bin Abdullah, Muhd Danish Daniel; Abdul Wahid, Mohd. Effendy; Sung, Yeong Yik

    2013-01-01

    Non-lethal heat shock boosts bacterial and viral disease tolerance in shrimp, possibly due to increases in endogenous heat shock protein 70 (Hsp70) and/or immune proteins. To further understand the mechanisms protecting shrimp against infection, Hsp70 and the mRNAs encoding the immune-related proteins prophenoloxidase (proPO), peroxinectin, penaeidin, crustin and hemocyanin were studied in post-larvae of the white-leg shrimp Litopenaeus vannamei, following a non-lethal heat shock. As indicated by RT-qPCR, a 30 min abrupt heat shock increased Hsp70 mRNA in comparison to non-heated animals. Immunoprobing of western blots and quantification by ELISA revealed that Hsp70 production after heat shock was correlated with enhanced Hsp70 mRNA. proPO and hemocyanin mRNA levels were augmented, whereas peroxinectin and crustin mRNA levels were unchanged following non-lethal heat shock. Penaeidin mRNA was decreased by all heat shock treatments. Thirty min abrupt heat shock failed to improve survival of post-larvae in a standardized challenge test with Vibrio harveyi, indicating that under the conditions of this study, L. vannamei tolerance to Vibrio infection was influenced neither by Hsp70 accumulation nor the changes in the immune-related proteins, observations dissimilar to other shrimp species examined. PMID:24039886

  9. Gimme shelter: how Vibrio fischeri successfully navigates an animal’s multiple environments

    PubMed Central

    Norsworthy, Allison N.; Visick, Karen L.

    2013-01-01

    Bacteria successfully colonize distinct niches because they can sense and appropriately respond to a variety of environmental signals. Of particular interest is how a bacterium negotiates the multiple, complex environments posed during successful infection of an animal host. One tractable model system to study how a bacterium manages a host’s multiple environments is the symbiotic relationship between the marine bacterium, Vibrio fischeri, and its squid host, Euprymna scolopes. V. fischeri encounters many different host surroundings ranging from initial contact with the squid to ultimate colonization of a specialized organ known as the light organ. For example, upon recognition of the squid, V. fischeri forms a biofilm aggregate outside the light organ that is required for efficient colonization. The bacteria then disperse from this biofilm to enter the organ, where they are exposed to nitric oxide, a molecule that can act as both a signal and an antimicrobial. After successfully managing this potentially hostile environment, V. fischeri cells finally establish their niche in the deep crypts of the light organ where the bacteria bioluminesce in a pheromone-dependent fashion, a phenotype that E. scolopes utilizes for anti-predation purposes. The mechanism by which V. fischeri manages these environments to outcompete all other bacterial species for colonization of E. scolopes is an important and intriguing question that will permit valuable insights into how a bacterium successfully associates with a host. This review focuses on specific molecular pathways that allow V. fischeri to establish this exquisite bacteria–host interaction. PMID:24348467

  10. Vibrio chromosome-specific families

    PubMed Central

    Lukjancenko, Oksana; Ussery, David W.

    2014-01-01

    We have compared chromosome-specific genes in a set of 18 finished Vibrio genomes, and, in addition, also calculated the pan- and core-genomes from a data set of more than 250 draft Vibrio genome sequences. These genomes come from 9 known species and 2 unknown species. Within the finished chromosomes, we find a core set of 1269 encoded protein families for chromosome 1, and a core of 252 encoded protein families for chromosome 2. Many of these core proteins are also found in the draft genomes (although which chromosome they are located on is unknown.) Of the chromosome specific core protein families, 1169 and 153 are uniquely found in chromosomes 1 and 2, respectively. Gene ontology (GO) terms for each of the protein families were determined, and the different sets for each chromosome were compared. A total of 363 different “Molecular Function” GO categories were found for chromosome 1 specific protein families, and these include several broad activities: pyridoxine 5' phosphate synthetase, glucosylceramidase, heme transport, DNA ligase, amino acid binding, and ribosomal components; in contrast, chromosome 2 specific protein families have only 66 Molecular Function GO terms and include many membrane-associated activities, such as ion channels, transmembrane transporters, and electron transport chain proteins. Thus, it appears that whilst there are many “housekeeping systems” encoded in chromosome 1, there are far fewer core functions found in chromosome 2. However, the presence of many membrane-associated encoded proteins in chromosome 2 is surprising. PMID:24672511

  11. Vibrio chromosome-specific families.

    PubMed

    Lukjancenko, Oksana; Ussery, David W

    2014-01-01

    We have compared chromosome-specific genes in a set of 18 finished Vibrio genomes, and, in addition, also calculated the pan- and core-genomes from a data set of more than 250 draft Vibrio genome sequences. These genomes come from 9 known species and 2 unknown species. Within the finished chromosomes, we find a core set of 1269 encoded protein families for chromosome 1, and a core of 252 encoded protein families for chromosome 2. Many of these core proteins are also found in the draft genomes (although which chromosome they are located on is unknown.) Of the chromosome specific core protein families, 1169 and 153 are uniquely found in chromosomes 1 and 2, respectively. Gene ontology (GO) terms for each of the protein families were determined, and the different sets for each chromosome were compared. A total of 363 different "Molecular Function" GO categories were found for chromosome 1 specific protein families, and these include several broad activities: pyridoxine 5' phosphate synthetase, glucosylceramidase, heme transport, DNA ligase, amino acid binding, and ribosomal components; in contrast, chromosome 2 specific protein families have only 66 Molecular Function GO terms and include many membrane-associated activities, such as ion channels, transmembrane transporters, and electron transport chain proteins. Thus, it appears that whilst there are many "housekeeping systems" encoded in chromosome 1, there are far fewer core functions found in chromosome 2. However, the presence of many membrane-associated encoded proteins in chromosome 2 is surprising. PMID:24672511

  12. Marine Bacillus spp. Associated With the Egg Capsule of Concholepas concholepas (Common Name “Loco”) Have an Inhibitory Activity Toward the Pathogen Vibrio parahaemolyticus

    Microsoft Academic Search

    Yanett Leyton; Carlos Riquelme

    2010-01-01

    The pandemic bacterium Vibrio parahaemolyticus, isolated from seawater, sediment, and marine organisms, is responsible for gastroenteric illnesses in humans and also cause\\u000a diseases in aquaculture industry in Chile and other countries around the world. In this study, bacterial flora with inhibitory\\u000a activity against pathogenic V. parahaemolyticus were collected from egg capsules of Concholepas concholepas and evaluated. The 16S rRNA fragment

  13. Study of the variation of ecotoxicity at different stages of domestic wastewater treatment using Vibrio-qinghaiensis sp.-Q67

    Microsoft Academic Search

    Xiaoyan Y. Ma; Xiaochang C. Wang; Yongjun J. Liu

    2011-01-01

    A bioassay using the luminescent bacterium Vibrio-qinghaiensis sp.-Q67 associated with solid-phase extraction (SPE) was developed for evaluating the variation of ecotoxicity along with the reduction of organic substances in a domestic wastewater treatment plant employing an oxidation ditch process. With effective elimination of the interference from all inorganic substances by the SPE operation, the ecotoxicity of the water, as expressed

  14. Predatory Bacteria as Natural Modulators of Vibrio parahaemolyticus and Vibrio vulnificus in Seawater and Oysters

    PubMed Central

    Fay, Johnna P.; Dickens, Keyana A.; Parent, Michelle A.; Soroka, Douglas S.; Boyd, E. Fidelma

    2012-01-01

    This study shows that naturally occurring Vibrio predatory bacteria (VPB) exert a major role in controlling pathogenic vibrios in seawater and shellfish. The growth and persistence of Vibrio parahaemolyticus and Vibrio vulnificus were assessed in natural seawater and in the Eastern oyster, Crassostrea virginica. The pathogens examined were V. vulnificus strain VV1003, V. parahaemolyticus O1:KUT (KUT stands for K untypeable), and V. parahaemolyticus O3:K6 and corresponding O3:K6 mutants deficient in the toxRS virulence regulatory gene or the rpoS alternative stress response sigma factor gene. Vibrios were selected for streptomycin resistance, which facilitated their enumeration. In natural seawater, oysters bioconcentrated each Vibrio strain for 24 h at 22°C; however, counts rapidly declined to near negligible levels by 72 h. In natural seawater with or without oysters, vibrios decreased more than 3 log units to near negligible levels within 72 h. Neither toxRS nor rpoS had a significant effect on Vibrio levels. In autoclaved seawater, V. parahaemolyticus O3:K6 counts increased 1,000-fold over 72 h. Failure of the vibrios to persist in natural seawater and oysters led to screening of the water samples for VPB on lawns of V. parahaemolyticus O3:K6 host cells. Many VPB, including Bdellovibrio and like organisms (BALOs; Bdellovibrio bacteriovorus and Bacteriovorax stolpii) and Micavibrio aeruginosavorus-like predators, were detected by plaque assay and electron microscopic analysis of plaque-purified isolates from Atlantic, Gulf Coast, and Hawaiian seawater. When V. parahaemolyticus O3:K6 was added to natural seawater containing trace amounts of VPB, Vibrio counts diminished 3 log units to nondetectable levels, while VPB increased 3 log units within 48 h. We propose a new paradigm that VPB are important modulators of pathogenic vibrios in seawater and oysters. PMID:22904049

  15. Predatory bacteria as natural modulators of Vibrio parahaemolyticus and Vibrio vulnificus in seawater and oysters.

    PubMed

    Richards, Gary P; Fay, Johnna P; Dickens, Keyana A; Parent, Michelle A; Soroka, Douglas S; Boyd, E Fidelma

    2012-10-01

    This study shows that naturally occurring Vibrio predatory bacteria (VPB) exert a major role in controlling pathogenic vibrios in seawater and shellfish. The growth and persistence of Vibrio parahaemolyticus and Vibrio vulnificus were assessed in natural seawater and in the Eastern oyster, Crassostrea virginica. The pathogens examined were V. vulnificus strain VV1003, V. parahaemolyticus O1:KUT (KUT stands for K untypeable), and V. parahaemolyticus O3:K6 and corresponding O3:K6 mutants deficient in the toxRS virulence regulatory gene or the rpoS alternative stress response sigma factor gene. Vibrios were selected for streptomycin resistance, which facilitated their enumeration. In natural seawater, oysters bioconcentrated each Vibrio strain for 24 h at 22°C; however, counts rapidly declined to near negligible levels by 72 h. In natural seawater with or without oysters, vibrios decreased more than 3 log units to near negligible levels within 72 h. Neither toxRS nor rpoS had a significant effect on Vibrio levels. In autoclaved seawater, V. parahaemolyticus O3:K6 counts increased 1,000-fold over 72 h. Failure of the vibrios to persist in natural seawater and oysters led to screening of the water samples for VPB on lawns of V. parahaemolyticus O3:K6 host cells. Many VPB, including Bdellovibrio and like organisms (BALOs; Bdellovibrio bacteriovorus and Bacteriovorax stolpii) and Micavibrio aeruginosavorus-like predators, were detected by plaque assay and electron microscopic analysis of plaque-purified isolates from Atlantic, Gulf Coast, and Hawaiian seawater. When V. parahaemolyticus O3:K6 was added to natural seawater containing trace amounts of VPB, Vibrio counts diminished 3 log units to nondetectable levels, while VPB increased 3 log units within 48 h. We propose a new paradigm that VPB are important modulators of pathogenic vibrios in seawater and oysters. PMID:22904049

  16. Primary Vibrio vulnificus sepsis in Kentucky.

    PubMed

    Ali, M B; Raff, M J

    1990-03-01

    Vibrio vulnificus is associated with infection acquired during contact with sea water or with seafood, and is seldom suspected by physicians in noncoastal states. The ease of transportation of fresh raw seafood has facilitated this organism's capacity to produce disease in geographic areas in which it was previously unseen. We have reported a case of fatal Vibrio vulnificus sepsis acquired from ingestion of fresh oysters in the inland United States. PMID:2315791

  17. Vibrio species as agents of elasmobranch disease

    Microsoft Academic Search

    D. J. Grimes; R. R. Colwell; J. Stemmler; H. Hada; D. Maneval; F. M. Hetrick; E. B. May; R. T. Jones; M. Stoskopf

    1984-01-01

    TwoVibrio species identified asV. damsela and a new sucrose-positiveVibrio sp.,V. carchariae sp. nov., were simultaneously isolated from a brown shark which died while being held in captivity at a large aquarium. Pathogenicity studies were subsequently conducted using a variety of elasmobranchs, including smooth dogfish and lemon sharks. Both bacterial strains proved pathogenic, causing death in nearly all of the elasmobranch

  18. "Build a Bacterium" Scavenger Hunt

    NSDL National Science Digital Library

    2012-09-26

    Working in small groups, learners receive a written scenario regarding a bacterium with a certain goal it must carry out. They must work together to decide what cell parts are needed to form the basic structure of any cell as well as to carry out the specific functions required by their scenario. To “build” their bacterium learners must negotiate and trade index cards with other groups to acquire their desired cell parts.

  19. Vibrio chromosomes share common history

    PubMed Central

    2010-01-01

    Background While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it is an open question to what extent the two chromosomes themselves share a common history since their formation. Results Single copy genes from each chromosome (142 genes from chromosome I and 42 genes from chromosome II) were identified from 19 sequenced Vibrionales genomes and their phylogenetic comparison suggests consistent phylogenies for each chromosome. Additionally, study of the gene organization and phylogeny of the respective origins of replication confirmed the shared history. Conclusions Thus, while elements within the chromosomes may have experienced significant genetic mobility, the backbones share a common history. This allows conclusions based on multilocus sequence analysis (MLSA) for one chromosome to be applied equally to both chromosomes. PMID:20459749

  20. VIBRIO VULNIFICUS EDUCATION WORKSHOP FOR THE FLORIDA MEDICAL COMMUNITY

    EPA Science Inventory

    Vibrio vulnificus is a naturally occurring microorganism that occurs warm marine and estuarine waters. The bacteria are concentrated by filter feeding shellfish. Certain immunocompromised individuals and those with liver disease can be adversely, even fatally affected by Vibrio...

  1. Adsorption and growth of Vibrio cholerae on chitin.

    PubMed Central

    Nalin, D R; Daya, V; Reid, A; Levine, M M; Cisneros, L

    1979-01-01

    Incubation of Vibrio cholerae of O-group serotype 1 with chitin particles resulted in adsorption of vibrios onto chitin; chitin-adsorbed V. cholerae survived exposure to acid better than nonadsorbed vibrios. V. cholerae multiplied in dialyzed chitin suspended in 4.2% NaCl, suggesting that adherence to ingested chitin of crustacea might be of epidemiological significance by providing a substrate for vibrio multiplication as well as protection from gastric acid during stomach transit. PMID:489131

  2. Control of luminous Vibrio species in penaeid aquaculture ponds

    Microsoft Academic Search

    D. J. W Moriarty

    1998-01-01

    A crisis has arisen in the prawn industry in many regions with the onset of disease, with Vibrio spp. being important major causal factors. The value of adding selected strains of Bacillus as probiotic bacteria to control the Vibrio is shown by comparing farms in Indonesia using the same water sources, which contained luminous Vibrio strains. The farms that did

  3. Mechanisms of iron regulation of luminescence in Vibrio fischeri

    SciTech Connect

    Haygood, M.G.; Nealson, K.H.

    1985-04-01

    Synthesis of luciferase is repressed by iron in the symbiotic bioluminescent bacterium Vibrio fischeri. Possible mechanisms of iron regulation of luciferase synthesis were tested with V. fischeri and with Escherichia coli clones containing plasmids carrying V. fischeri luminescence genes. Experiments were conducted in complete medium with and without the synthetic iron chelator ethylenediamine-di(o-hydroxyphenyl acetic acid). Comparison of the effect of ethylenediamine-di(o-hydroxyphenyl acetic acid) and another growth inhibitor, (2-n-heptyl-4-hydroxyquinoline-N-oxide), showed that iron repression is not due to inhibition of growth. A quantitative bioassay for autoinducer was developed with E. coli HB101 containing pJE411, a plasmid carrying V. fischeri luminescence genes with a transcriptional fusion between luxI and E. coli lacZ. Bioassay experiments showed no effect of iron on either autoinducer activity or production (before induction) or transcription of the lux operon. Ethylenediamine-di(o-hydroxyphenyl acetic acid) did not affect luciferase induction in E. coli strains with wild-type iron assimilation or impaired iron assimilation bearing pJE202 (a plasmid with functional V. fischeri lux genes), suggesting that the genes responsible for the iron effect are missing or substituted in these clones. Two models are consistent with the data: (i) iron represses autoinducer transport, and (ii) iron acts through an autoinduction-independent regulatory system (e.g., an iron repressor).

  4. The pathogenesis, detection, and prevention of Vibrio parahaemolyticus

    PubMed Central

    Wang, Rongzhi; Zhong, Yanfang; Gu, Xiaosong; Yuan, Jun; Saeed, Abdullah F.; Wang, Shihua

    2015-01-01

    Vibrio parahaemolyticus, a Gram-negative motile bacterium that inhabits marine and estuarine environments throughout the world, is a major food-borne pathogen that causes life-threatening diseases in humans after the consumption of raw or undercooked seafood. The global occurrence of V. parahaemolyticus accentuates the importance of investigating its virulence factors and their effects on the human host. This review describes the virulence factors of V. parahaemolyticus reported to date, including hemolysin, urease, two type III secretion systems and two type VI secretion systems, which both cause both cytotoxicity in cultured cells and enterotoxicity in animal models. We describe various types of detection methods, based on virulence factors, that are used for quantitative detection of V. parahaemolyticus in seafood. We also discuss some useful preventive measures and therapeutic strategies for the diseases mediated by V. parahaemolyticus, which can reduce, to some extent, the damage to humans and aquatic animals attributable to V. parahaemolyticus. This review extends our understanding of the pathogenic mechanisms of V. parahaemolyticus mediated by virulence factors and the diseases it causes in its human host. It should provide new insights for the diagnosis, treatment, and prevention of V. parahaemolyticus infection. PMID:25798132

  5. Occurrence of Vibrio vulnificus in fish and shellfish available from markets in China.

    PubMed

    Yano, Yutaka; Yokoyama, Masahito; Satomi, Masataka; Oikawa, Hiroshi; Chen, Shun-Sheng

    2004-08-01

    Vibrio vulnificus is a naturally occurring estuarine bacterium often associated with disease such as septicemia in humans following consumption of raw and lightly cooked seafood. In China and neighboring countries, rapid economic growth has encouraged increased consumption of seafood, and dietary habits are changing, with more people eating raw fish. In this study, the prevalence of V. vulnificus was investigated in 48 samples from 11 species of live seafood available from markets in coastal cities of China. The bacterium was detected in four of four razor clam samples, in seven of seven giant tiger prawn samples, and in five of nine mantis shrimp samples. The bacterium was also found in water samples of the prawn aquaria at the markets. The maximum level of V. vulnificus was 3.4 log CFU/g in the razor clam samples and 4.9 log CFU/g in the prawn samples by a direct spreading method. Differential bacterial counts on the prawn body revealed that most of the bacteria were found on the shells (exoskeletons), with very few in the edible muscle. However, dense populations can be found in the intestines. Biochemical tests indicated that the isolates of V. vulnificus were biotype 1 strain, which is pathogenic to humans. These isolates were susceptible to ampicillin, penicillin, kanamycin, streptomycin, and erythromycin. These results suggest that V. vulnificus is a potential health hazard to humans in cities consuming and handling live shellfish, especially giant tiger prawns. PMID:15330524

  6. Occurrence of Vibrio parahaemolyticus and Related Hemolytic Vibrios in Marine Environments of Washington State 1

    PubMed Central

    Baross, J.; Liston, J.

    1970-01-01

    Samples of sediment, water, and fauna were tested for the presence of Vibrio parahaemolyticus and the related biotype V. alginolyticus. Altogether, 379 samples were analyzed quantitatively by using a starch-agar medium. Invertebrate and sediment samples were invariably positive for V. parahaemolyticus, whereas water samples were quite variable. Samples of the Pacific oyster (Crassostrea gigas), obtained on a regular basis for 26 months from a single environment, showed a close correlation between total numbers of mesophilic vibrios and the overlying water temperature; the seasonal counts of oysters ranged from less than 10 to greater than 100,000 per g. Ecological implications and possible pathogenicity of these vibrios are discussed. PMID:4921057

  7. Pathogenicity of vibrios in fish: An overview

    NASA Astrophysics Data System (ADS)

    Jun, Li; Woo, Norman Y. S.

    2003-10-01

    Bacteria of the genus Vibrio are ubiquitously distributed in the marine environment. Due to the rapid expansion of intensive mariculture and the consequent deterioration of culture conditions, more and more Vibrio spp. have been recognized as pathogenic agents in outbreaks of vibriosis, a serious epizootic disease affecting most wild and farmed fish species worldwide, which has become the most important limiting factor for the development of intensive mariculture industry. Attempts have been made to understand the pathogenicity of vibrios in host fish with the ultimate aim of elucidating the best means for disease control. After an extensive literature survey of the recent advances in the field of fish vibriosis, the pathological changes, virulence factors and associated potential pathogenic mechanisms, transmission routes and related environmental factors involved in outbreak of vibriosis, as well as the controlling strategies are reviewed in the present paper.

  8. Cholera and other vibrio-associated diarrhoeas*

    PubMed Central

    1980-01-01

    In recent years, there have been major advances in knowledge of Vibrio species and related organisms that are responsible for diarrhoeal diseases, particularly V. cholerae O-Group 1 (epidemic strains), atypical V. cholerae O-Group 1, non-O-Group 1 V. cholerae (non-epidemic strains), V. parahaemolyticus, V. alginolyticus, and ”Group F vibrios”. This article reviews the important new information, and identifies gaps in our knowledge, on aspects such as the epidemiology and bacteriology of vibrios, environmental surveillance for V. cholerae O-Group 1, phage and vibriocin typing of V. cholerae, and cholera enterotoxin, and its relevance to pathogenesis, immunity, and vaccine development. In each of these areas priorities for further research are recommended. PMID:6968251

  9. Proteases Produced by Vibrio cholerae and Other Pathogenic Vibrios: Pathogenic Roles and Expression

    Microsoft Academic Search

    Sumio Shinoda

    \\u000a Pathogenic vibrios produce various pathogenic factors such as enterotoxin, hemolysin, cytotoxin, protease, siderophore, adhesive\\u000a factor, and hemagglutinin. Direct toxic factors such as enterotoxin, hemolysin, and cytotoxin are related to the symptoms,\\u000a whereas siderophore and adhesive factors may cause indirect factors, which play roles in the establishment of the infection.\\u000a The proteases produced by pathogenic vibrios are long recognized to play

  10. A Potential Capacitance Detection and Enumeration Method for Vibrio cholerae and Vibrio vulnificus

    Microsoft Academic Search

    Douglas L. Marshall; David N. Domma; Robert M. Grodner

    1999-01-01

    Salt content of basal modified cellobiose-polymyxin B-colistin (mCPC) medium was varied to assess impedance-based detection of Vibrio cholerae and Vibrio vulnificus. Several sodium salts were tested as substitutes for NaCl. Bactometer detection times (h) were compared to find the optimal salt and its concentration. Results using tryptic soy broth indicated 2% Na2HPO4 was the best NaCl replacement. Use of 2%

  11. Vibrio mimicus diarrhea following ingestion of raw turtle eggs.

    PubMed Central

    Campos, E; Bolaños, H; Acuña, M T; Díaz, G; Matamoros, M C; Raventós, H; Sánchez, L M; Sánchez, O; Barquero, C

    1996-01-01

    Clinical and epidemiological characteristics of diarrhea associated with Vibrio mimicus were identified in 33 hospitalized patients referred to the Costa Rican National Diagnostic Laboratory Network between 1991 and 1994. The relevant symptoms presented by patients included abundant watery diarrhea, vomiting, and severe dehydration that required intravenous Dhaka solution in 83% of patients but not fever. Seroconversion against V. mimicus was demonstrated in four patients, from whom acute- and convalescent-phase sera were obtained. Those sera did not show cross-reaction when tested against Vibrio cholerae O1 strain VC-12. All the V. mimicus isolates from these cases produced cholera toxin (CT) and were susceptible to commonly used antibiotics. Attempts to isolate this bacterium from stool samples of 127 healthy persons were not successful. Consumption of raw turtle eggs was recalled by 11 of the 19 (58%) individuals interviewed. All but two V. mimicus diarrheal cases were sporadic. These two had a history of a common source of turtle (Lepidochelys olivacea) eggs for consumption, and V. mimicus was isolated from eggs from the same source (a local market). Among the strains, variations in the antimicrobial susceptibility pattern were observed. None of the strains recovered from market turtle eggs nor the four isolates from river water showed CT production. Further efforts to demonstrate the presence of CT-producing V. mimicus strains in turtle eggs were made. Successful results were obtained when nest eggs were tested. In this case, it was possible to isolate CT- and non-CT-producing strains, even from the same egg. For CT detection we used PCR, enzyme-linked immunosorbent assay (ELISA), and Y-1 cell assay, obtaining a 100% correlation between ELISA and PCR results. Primers Col-1 and Col-2, originally described as specific for the V. cholerae O1 ctxA gene, also amplified a 302-bp segment with an identical restriction map from V. mimicus. These results have important implications for epidemiological surveillance in tropical countries where turtle eggs are used for human consumption, serving as potential sources of cholera-like diarrhea. PMID:8919774

  12. Predicting the Distribution of Vibrio spp. in the Chesapeake Bay: A Vibrio cholerae Case Study

    PubMed Central

    Magny, Guillaume Constantin de; Long, Wen; Brown, Christopher W.; Hood, Raleigh R.; Huq, Anwar; Murtugudde, Raghu; Colwell, Rita R.

    2010-01-01

    Vibrio cholerae, the causative agent of cholera, is a naturally occurring inhabitant of the Chesapeake Bay and serves as a predictor for other clinically important vibrios, including Vibrio parahaemolyticus and Vibrio vulnificus. A system was constructed to predict the likelihood of the presence of V. cholerae in surface waters of the Chesapeake Bay, with the goal to provide forecasts of the occurrence of this and related pathogenic Vibrio spp. Prediction was achieved by driving an available multivariate empirical habitat model estimating the probability of V. cholerae within a range of temperatures and salinities in the Bay, with hydrodynamically generated predictions of ambient temperature and salinity. The experimental predictions provided both an improved understanding of the in situ variability of V. cholerae, including identification of potential hotspots of occurrence, and usefulness as an early warning system. With further development of the system, prediction of the probability of the occurrence of related pathogenic vibrios in the Chesapeake Bay, notably V. parahaemolyticus and V. vulnificus, will be possible, as well as its transport to any geographical location where sufficient relevant data are available. PMID:20145974

  13. RECA EXPRESSION IN RESPONSE TO SOLAR UVR IN THE MARINE BACTERIUM VIBRIO NATRIEGENS.

    EPA Science Inventory

    Medicinal plants may carry residuals of environmentally persistent pesticides or assimilate heavy metals in varying degrees. Several factors may influence contaminant accumulation, including species, level and duration of contaminant exposure, and topography. As part of a program...

  14. Thermal Stress Triggers Broad Pocillopora damicornis Transcriptomic Remodeling, while Vibrio coralliilyticus Infection Induces a More Targeted Immuno-Suppression Response

    PubMed Central

    Vidal-Dupiol, Jeremie; Dheilly, Nolwenn M.; Rondon, Rodolfo; Grunau, Christoph; Cosseau, Céline; Smith, Kristina M.; Freitag, Michael; Adjeroud, Mehdi; Mitta, Guillaume

    2014-01-01

    Global change and its associated temperature increase has directly or indirectly changed the distributions of hosts and pathogens, and has affected host immunity, pathogen virulence and growth rates. This has resulted in increased disease in natural plant and animal populations worldwide, including scleractinian corals. While the effects of temperature increase on immunity and pathogen virulence have been clearly identified, their interaction, synergy and relative weight during pathogenesis remain poorly documented. We investigated these phenomena in the interaction between the coral Pocillopora damicornis and the bacterium Vibrio coralliilyticus, for which the infection process is temperature-dependent. We developed an experimental model that enabled unraveling the effects of thermal stress, and virulence vs. non-virulence of the bacterium. The physiological impacts of various treatments were quantified at the transcriptome level using a combination of RNA sequencing and targeted approaches. The results showed that thermal stress triggered a general weakening of the coral, making it more prone to infection, non-virulent bacterium induced an ‘efficient’ immune response, whereas virulent bacterium caused immuno-suppression in its host. PMID:25259845

  15. EFFECT OF AGGREGATION ON VIBRIO CHOLERAE INACTIVATION

    EPA Science Inventory

    Extensive research has shown that microorganisms exhibit increased resistance due to clumping, aggregation, particle association, or modification of antecedent growth conditions. During the course of investigating a major water-borne Vibrio cholerae outbreak in Peru, U.S. EPA inv...

  16. Preventing maritime transfer of toxigenic Vibrio cholerae.

    PubMed

    Cohen, Nicole J; Slaten, Douglas D; Marano, Nina; Tappero, Jordan W; Wellman, Michael; Albert, Ryan J; Hill, Vincent R; Espey, David; Handzel, Thomas; Henry, Ariel; Tauxe, Robert V

    2012-10-01

    Organisms, including Vibrio cholerae, can be transferred between harbors in the ballast water of ships. Zones in the Caribbean region where distance from shore and water depth meet International Maritime Organization guidelines for ballast water exchange are extremely limited. Use of ballast water treatment systems could mitigate the risk for organism transfer. PMID:23017338

  17. Preventing Maritime Transfer of Toxigenic Vibrio cholerae

    PubMed Central

    Slaten, Douglas D.; Marano, Nina; Tappero, Jordan W.; Wellman, Michael; Albert, Ryan J.; Hill, Vincent R.; Espey, David; Handzel, Thomas; Henry, Ariel; Tauxe, Robert V.

    2012-01-01

    Organisms, including Vibrio cholerae, can be transferred between harbors in the ballast water of ships. Zones in the Caribbean region where distance from shore and water depth meet International Maritime Organization guidelines for ballast water exchange are extremely limited. Use of ballast water treatment systems could mitigate the risk for organism transfer. PMID:23017338

  18. Vibrio parahaemolyticus: A concern of seafood safety

    Microsoft Academic Search

    Yi-Cheng Su; Chengchu Liu

    2007-01-01

    Vibrio parahaemolyticus is a human pathogen that is widely distributed in the marine environments. This organism is frequently isolated from a variety of raw seafoods, particularly shellfish. Consumption of raw or undercooked seafood contaminated with V. parahaemolyticus may lead to development of acute gastroenteritis characterized by diarrhea, headache, vomiting, nausea, and abdominal cramps. This pathogen is a common cause of

  19. Zebrafish as a Natural Host Model for Vibrio cholerae Colonization and Transmission

    PubMed Central

    Runft, Donna L.; Mitchell, Kristie C.; Abuaita, Basel H.; Allen, Jonathan P.; Bajer, Sarah; Ginsburg, Kevin; Neely, Melody N.

    2014-01-01

    The human diarrheal disease cholera is caused by the aquatic bacterium Vibrio cholerae. V. cholerae in the environment is associated with several varieties of aquatic life, including insect egg masses, shellfish, and vertebrate fish. Here we describe a novel animal model for V. cholerae, the zebrafish. Pandemic V. cholerae strains specifically colonize the zebrafish intestinal tract after exposure in water with no manipulation of the animal required. Colonization occurs in close contact with the intestinal epithelium and mimics colonization observed in mammals. Zebrafish that are colonized by V. cholerae transmit the bacteria to naive fish, which then become colonized. Striking differences in colonization between V. cholerae classical and El Tor biotypes were apparent. The zebrafish natural habitat in Asia heavily overlaps areas where cholera is endemic, suggesting that zebrafish and V. cholerae evolved in close contact with each other. Thus, the zebrafish provides a natural host model for the study of V. cholerae colonization, transmission, and environmental survival. PMID:24375135

  20. The secret languages of coevolved symbioses: Insights from the Euprymna scolopes-Vibrio fischeri symbiosis

    PubMed Central

    McFall-Ngai, Margaret; Heath-Heckman, Elizabeth A. C.; Gillette, Amani A.; Peyer, Suzanne M.; Harvie, Elizabeth A.

    2011-01-01

    Recent research on a wide variety of systems has demonstrated that animals generally coevolve with their microbial symbionts. Although such relationships are most often established anew each generation, the partners associate with fidelity, i.e., they form exclusive alliances within the context of rich communities of non-symbiotic environmental microbes. The mechanisms by which this exclusivity is achieved and maintained remain largely unknown. Studies of the model symbiosis between the Hawaiian squid Euprymna scolopes and the marine luminous bacterium Vibrio fischeri provide evidence that the interplay between evolutionarily conserved features of the innate immune system, most notably MAMP/PRR interactions, and a specific feature of this association, i.e., luminescence, are critical for development and maintenance of this association. As such, in this partnership and perhaps others, symbiotic exclusivity is mediated by the synergism between a general animal-microbe ‘language’ and a ‘secret language’ that is decipherable only by the specific partners involved. PMID:22154556

  1. Evidence for the Role of Horizontal Transfer in Generating pVT1, a Large Mosaic Conjugative Plasmid from the Clam Pathogen, Vibrio tapetis

    PubMed Central

    Bidault-Toffin, Adeline; Le Chevalier, Patrick; Bouloc, Philippe; Paillard, Christine; Jacq, Annick

    2011-01-01

    The marine bacterium Vibrio tapetis is the causative agent of the brown ring disease, which affects the clam Ruditapes philippinarum and causes heavy economic losses in North of Europe and in Eastern Asia. Further characterization of V. tapetis isolates showed that all the investigated strains harbored at least one large plasmid. We determined the sequence of the 82,266 bp plasmid pVT1 from the CECT4600T reference strain and analyzed its genetic content. pVT1 is a mosaic plasmid closely related to several conjugative plasmids isolated from Vibrio vulnificus strains and was shown to be itself conjugative in Vibrios. In addition, it contains DNA regions that have similarity with several other plasmids from marine bacteria (Vibrio sp., Shewanella sp., Listonella anguillarum and Photobacterium profundum). pVT1 contains a number of mobile elements, including twelve Insertion Sequences or inactivated IS genes and an RS1 phage element related to the CTXphi phage of V. cholerae. The genetic organization of pVT1 underscores an important role of horizontal gene transfer through conjugative plasmid shuffling and transposition events in the acquisition of new genetic resources and in generating the pVT1 modular organization. In addition, pVT1 presents a copy number of 9, relatively high for a conjugative plasmid, and appears to belong to a new type of replicon, which may be specific to Vibrionaceae and Shewanelleacae. PMID:21326607

  2. The dual nature of haemocyanin in the establishment and persistence of the squid-vibrio symbiosis.

    PubMed

    Kremer, Natacha; Schwartzman, Julia; Augustin, René; Zhou, Lawrence; Ruby, Edward G; Hourdez, Stéphane; McFall-Ngai, Margaret J

    2014-06-22

    We identified and sequenced from the squid Euprymna scolopes two isoforms of haemocyanin that share the common structural/physiological characteristics of haemocyanin from a closely related cephalopod, Sepia officinalis, including a pronounced Bohr effect. We examined the potential roles for haemocyanin in the animal's symbiosis with the luminous bacterium Vibrio fischeri. Our data demonstrate that, as in other cephalopods, the haemocyanin is primarily synthesized in the gills. It transits through the general circulation into other tissues and is exported into crypt spaces that support the bacterial partner, which requires oxygen for its bioluminescence. We showed that the gradient of pH between the circulating haemolymph and the matrix of the crypt spaces in adult squid favours offloading of oxygen from the haemocyanin to the symbionts. Haemocyanin is also localized to the apical surfaces and associated mucus of a juvenile-specific epithelium on which the symbionts gather, and where their specificity is determined during the recruitment into the association. The haemocyanin has an antimicrobial activity, which may be involved in this enrichment of V. fischeri during symbiont initiation. Taken together, these data provide evidence that the haemocyanin plays a role in shaping two stages of the squid-vibrio partnership. PMID:24807261

  3. Genomic and proteomic analyses of the coral pathogen Vibrio coralliilyticus reveal a diverse virulence repertoire

    PubMed Central

    de O Santos, Eidy; Alves, Nelson; Dias, Graciela M; Mazotto, Ana Maria; Vermelho, Alane; Vora, Gary J; Wilson, Bryan; Beltran, Victor H; Bourne, David G; Le Roux, Frédérique; Thompson, Fabiano L

    2011-01-01

    Vibrio coralliilyticus has been implicated as an important pathogen of coral species worldwide. In this study, the nearly complete genome of Vibrio coralliilyticus strain P1 (LMG23696) was sequenced and proteases implicated in virulence of the strain were specifically investigated. The genome sequence of P1 (5?513?256?bp in size) consisted of 5222 coding sequences and 58 RNA genes (53 tRNAs and at least 5 rRNAs). Seventeen metalloprotease and effector (vgrG, hlyA and hcp) genes were identified in the genome and expressed proteases were also detected in the secretome of P1. As the VcpA zinc-metalloprotease has been considered an important virulence factor of V. coralliilyticus, a vcpA deletion mutant was constructed to evaluate the effect of this gene in animal pathogenesis. Both wild-type and mutant (?vcpA) strains exhibited similar virulence characteristics that resulted in high mortality in Artemia and Drosophila pathogenicity bioassays and strong photosystem II inactivation of the coral dinoflagellate endosymbiont (Symbiodinium). In contrast, the ?vcpA mutant demonstrated higher hemolytic activity and secreted 18 proteins not secreted by the wild type. These proteins included four types of metalloproteases, a chitinase, a hemolysin-related protein RbmC, the Hcp protein and 12 hypothetical proteins. Overall, the results of this study indicate that V. coralliilyticus strain P1 has a diverse virulence repertoire that possibly enables this bacterium to be an efficient animal pathogen. PMID:21451583

  4. A luminescent bacterium assay of fusaric acid produced by Fusarium proliferatum from banana.

    PubMed

    Li, Jing; Jiang, Guoxiang; Yang, Bao; Dong, Xinhong; Feng, Linyan; Lin, Sen; Chen, Feng; Ashraf, Muhammad; Jiang, Yueming

    2012-01-01

    Fusarium proliferatum was isolated as a major pathogen causing the Fusarium disease in harvested banana fruit. One of its major compounds, fusaric acid, was identified by high-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS). Because the light intensity of the luminescent bacterium Vibrio qinghaiensis sp. Nov. Q67 can be inhibited by fusaric acid, the fusaric acid content of F. proliferatum was assessed and compared by both the HPLC and luminescent bacterium methods. Although both methods afforded almost similar values of fusaric acid, the latter indicated slightly lower content than the former. Czapek medium was more suitable for the growth of F. proliferatum and fusaric acid production than modified Richard medium, with an optimum pH of approximately 7.0. However, no significant (P < 0.05) correlation was obtained between the fusaric acid production and growth of mycelia of F. proliferatum. The study suggests that the bioevaluation by use of the luminescent bacterium was effective in monitoring fusaric acid production by F. proliferatum without expensive equipment. PMID:22105299

  5. Ligand-Induced Asymmetry in Histidine Sensor Kinase Complex Regulates Quorum Sensing

    SciTech Connect

    Neiditch,M.; Federle, M.; Pompeani, A.; Kelly, R.; Swem, D.; Jeffrey, P.; Bassler, B.; Hughson, F.

    2006-01-01

    Bacteria sense their environment using receptors of the histidine sensor kinase family, but how kinase activity is regulated by ligand binding is not well understood. Autoinducer-2 (AI-2), a secreted signaling molecule originally identified in studies of the marine bacterium Vibrio harveyi, regulates quorum-sensing responses and allows communication between different bacterial species. AI-2 signal transduction in V. harveyi requires the integral membrane receptor LuxPQ, comprised of periplasmic binding protein (LuxP) and histidine sensor kinase (LuxQ) subunits. Combined X-ray crystallographic and functional studies show that AI-2 binding causes a major conformational change within LuxP, which in turn stabilizes a quaternary arrangement in which two LuxPQ monomers are asymmetrically associated. We propose that formation of this asymmetric quaternary structure is responsible for repressing the kinase activity of both LuxQ subunits and triggering the transition of V. harveyi into quorum-sensing mode.

  6. TetR-Type Transcriptional Regulator VtpR Functions as a Global Regulator in Vibrio tubiashii?

    PubMed Central

    Hasegawa, Hiroaki; Häse, Claudia C.

    2009-01-01

    Vibrio tubiashii, a causative agent of severe shellfish larval disease, produces multiple extracellular proteins, including a metalloprotease (VtpA), as potential virulence factors. We previously reported that VtpA is toxic for Pacific oyster (Crassostrea gigas) larvae. In this study, we show that extracellular protease production by V. tubiashii was much reduced by elevated salt concentrations, as well as by elevated temperatures. In addition, V. tubiashii produced dramatically less protease in minimal salts medium supplemented with glucose or sucrose as the sole carbon source than with succinate. We identified a protein that belongs to the TetR family of transcriptional regulators, VtpR, which showed high homology with V. cholerae HapR. We conclude that VtpR activates VtpA production based on the following: (i) a VtpR-deficient V. tubiashii mutant did not produce extracellular proteases, (ii) the mutant showed reduced expression of a vtpA-lacZ fusion, and (iii) VtpR activated vtpA-lacZ in a V. cholerae heterologous background. Moreover, we show that VtpR activated the expression of an additional metalloprotease gene (vtpB). The deduced VtpB sequence showed high homology with a metalloprotease, VhpA, from V. harveyi. Furthermore, the vtpR mutant strain produced reduced levels of extracellular hemolysin, which is attributed to the lower expression of the V. tubiashii hemolysin genes (vthAB). The VtpR-deficient mutant also had negative effects on bacterial motility and did not demonstrate toxicity to oyster larvae. Together, these findings establish that the V. tubiashii VtpR protein functions as a global regulator controlling an array of potential virulence factors. PMID:19837838

  7. TetR-type transcriptional regulator VtpR functions as a global regulator in Vibrio tubiashii.

    PubMed

    Hasegawa, Hiroaki; Häse, Claudia C

    2009-12-01

    Vibrio tubiashii, a causative agent of severe shellfish larval disease, produces multiple extracellular proteins, including a metalloprotease (VtpA), as potential virulence factors. We previously reported that VtpA is toxic for Pacific oyster (Crassostrea gigas) larvae. In this study, we show that extracellular protease production by V. tubiashii was much reduced by elevated salt concentrations, as well as by elevated temperatures. In addition, V. tubiashii produced dramatically less protease in minimal salts medium supplemented with glucose or sucrose as the sole carbon source than with succinate. We identified a protein that belongs to the TetR family of transcriptional regulators, VtpR, which showed high homology with V. cholerae HapR. We conclude that VtpR activates VtpA production based on the following: (i) a VtpR-deficient V. tubiashii mutant did not produce extracellular proteases, (ii) the mutant showed reduced expression of a vtpA-lacZ fusion, and (iii) VtpR activated vtpA-lacZ in a V. cholerae heterologous background. Moreover, we show that VtpR activated the expression of an additional metalloprotease gene (vtpB). The deduced VtpB sequence showed high homology with a metalloprotease, VhpA, from V. harveyi. Furthermore, the vtpR mutant strain produced reduced levels of extracellular hemolysin, which is attributed to the lower expression of the V. tubiashii hemolysin genes (vthAB). The VtpR-deficient mutant also had negative effects on bacterial motility and did not demonstrate toxicity to oyster larvae. Together, these findings establish that the V. tubiashii VtpR protein functions as a global regulator controlling an array of potential virulence factors. PMID:19837838

  8. Pathogenic vibrios in environmental, seafood and clinical sources in Germany.

    PubMed

    Huehn, Stephan; Eichhorn, Christin; Urmersbach, Sara; Breidenbach, Janina; Bechlars, Silke; Bier, Nadja; Alter, Thomas; Bartelt, Edda; Frank, Christina; Oberheitmann, Boris; Gunzer, Florian; Brennholt, Nicole; Böer, Simone; Appel, Bernd; Dieckmann, Ralf; Strauch, Eckhard

    2014-10-01

    Bacteria of the family Vibrionaceae naturally occur in marine and estuarine environments. Only few species of Vibrionaceae are associated with human cases of gastroenteritis, ear and wound infections, caused by ingestion of seafood or contact with Vibrio containing water. Increasing consumption of seafood (fish, fishery products and shellfish) poses a possible source of Vibrio infections in Germany. Additionally, there is a growing concern that abundances of pathogenic vibrios may increase in German coastal waters as a result of e.g. climate change resulting in probably rising surface water temperatures. According to the One Health concept the VibrioNet consortium started in 2010 to investigate the occurrence and relevance of non-cholera vibrios of human concern in Germany. Vibrios from environmental, seafood and clinical sources were analyzed with the aim to find connections between different reservoirs or sources and to identify potential ways of transmission of these pathogens to assess the risk of infections associated with them. Potentially pathogenic strains mostly belong to the species Vibrio parahaemolyticus, Vibrio vulnificus and non-O1/non-O139 Vibrio cholerae. Investigations on imported seafood and mussels from primary production areas confirmed the frequent occurrence of these species. Moreover, studies of German coastal waters and sediments showed the presence and seasonality of these marine bacteria. So far the incidence of clinical cases of vibriosis in Germany is low. Between 1994 and 2013 thirteen cases of Vibrio spp. associated wound infections and/or septicaemia have been reported. However, the high prevalence of vibrios in aquatic environments and aquatic organisms is of concern and demands continued control of food and surveillance for clinical infections with pathogenic vibrios. PMID:25129553

  9. Genome assortment, not serogroup, defines Vibrio cholerae pandemic strains

    SciTech Connect

    Brettin, Thomas S [Los Alamos National Laboratory; Bruce, David C [Los Alamos National Laboratory; Challacombe, Jean F [Los Alamos National Laboratory; Detter, John C [Los Alamos National Laboratory; Han, Cliff S [Los Alamos National Laboratory; Munik, A C [Los Alamos National Laboratory; Chertkov, Olga [Los Alamos National Laboratory; Meincke, Linda [Los Alamos National Laboratory; Saunders, Elizabeth [Los Alamos National Laboratory; Choi, Seon Y [SEOUL NATL. UNIV.; Haley, Bradd J [U. MARYLAND; Taviani, Elisa [U. MARYLAND; Jeon, Yoon - Seong [INTL. VACCINE INST. SEOUL; Kim, Dong Wook [INTL. VACCINE INST. SEOUL; Lee, Jae - Hak [SEOUL NATL. UNIV.; Walters, Ronald A [PNNL; Hug, Anwar [NATL. INST. CHOLERIC ENTERIC DIS.; Colwell, Rita R [U. MARYLAND

    2009-01-01

    Vibrio cholerae, the causative agent of cholera, is a bacterium autochthonous to the aquatic environment, and a serious public health threat. V. cholerae serogroup O1 is responsible for the previous two cholera pandemics, in which classical and El Tor biotypes were dominant in the 6th and the current 7th pandemics, respectively. Cholera researchers continually face newly emerging and re-emerging pathogenic clones carrying combinations of new serogroups as well as of phenotypic and genotypic properties. These genotype and phenotype changes have hampered control of the disease. Here we compare the complete genome sequences of 23 strains of V. cholerae isolated from a variety of sources and geographical locations over the past 98 years in an effort to elucidate the evolutionary mechanisms governing genetic diversity and genesis of new pathogenic clones. The genome-based phylogeny revealed 12 distinct V. cholerae phyletic lineages, of which one, designated the V. cholerae core genome (CG), comprises both O1 classical and EI Tor biotypes. All 7th pandemic clones share nearly identical gene content, i.e., the same genome backbone. The transition from 6th to 7th pandemic strains is defined here as a 'shift' between pathogenic clones belonging to the same O1 serogroup, but from significantly different phyletic lineages within the CG clade. In contrast, transition among clones during the present 7th pandemic period can be characterized as a 'drift' between clones, differentiated mainly by varying composition of laterally transferred genomic islands, resulting in emergence of variants, exemplified by V.cholerae serogroup O139 and V.cholerae O1 El Tor hybrid clones that produce cholera toxin of classical biotype. Based on the comprehensive comparative genomics presented in this study it is concluded that V. cholerae undergoes extensive genetic recombination via lateral gene transfer, and, therefore, genome assortment, not serogroup, should be used to define pathogenic V. cholerae clones.

  10. Mechanistic insights into filamentous phage integration in Vibrio cholerae

    PubMed Central

    Das, Bhabatosh

    2014-01-01

    Vibrio cholerae, the etiological agent of acute diarrhoeal disease cholera, harbors large numbers of lysogenic filamentous phages, contribute significantly to the host pathogenesis and provide fitness factors to the pathogen that help the bacterium to survive in natural environment. Most of the vibriophage genomes are not equipped with integrase and thus exploit two host-encoded tyrosine recombinases, XerC and XerD, for lysogenic conversion. Integration is site-specific and it occurs at dimer resolution site (dif) of either one or both chromosomes of V. cholerae. Each dif sequence contains two recombinase-binding sequences flanking a central region. The integration follows a sequential strand exchanges between dif and attP sites within a DNA-protein complex consisting of one pair of each recombinase and two DNA fragments. During entire process of recombination, both the DNA components and recombinases of the synaptic complex keep transiently interconnected. Within the context of synaptic complex, both of the actuated enzymes mediate cleavage of phosphodiester bonds. First cleavage generates a phosphotyrosyl-linked recombinase-DNA complex at the recombinase binding sequence and free 5?-hydroxyl end at the first base of the central region. Following the cleavage, the exposed bases with 5?-hydroxyl ends of the central region of dif and attP sites melt from their complementary strands and react with the recombinase-DNA phosphotyrosyl linkage of their recombining partner. Subsequent ligation between dif and attP strands requires complementary base pair interactions at the site of phosphodiester bond formation. Integration mechanism is mostly influenced by the compatibility of dif and attP sequences. dif sites are highly conserved across bacterial phyla. Different phage genomes have different attP sequences; therefore they rely on different mechanisms for integration. Here, I review our current understanding of integration mechanisms used by the vibriophages. PMID:25506341

  11. Transformation Experiment Using Bioluminescence Genes of "Vibrio fischeri."

    ERIC Educational Resources Information Center

    Slock, James

    1995-01-01

    Bioluminescence transformation experiments show students the excitement and power of recombinant DNA technology. This laboratory experiment utilizes two plasmids of "Vibrio fischeri" in a transformation experiment. (LZ)

  12. Applied studies on the viability of El Tor vibrios*

    PubMed Central

    Pesigan, T. P.; Plantilla, J.; Rolda, M.

    1967-01-01

    The viability of El Tor vibrios was tested at various temperatures in foodstuffs, kitchen utensils, and water after these materials had been directly contaminated with stools of cholera patients or carriers from the Philippines, collected in 1963-64. The period of survival of vibrios in foodstuffs was 2-5 days at room temperature (30°C-32°C) and as long as 9 days under refrigeration (5°C-10°C). Vibrios survived even longer in refrigerated water. The period of survival was shorter for all materials contaminated with carriers' stools, which contain fewer vibrios. Chlorinated lime was more effective than potassium permanganate as a decontaminant. PMID:4870081

  13. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3930 Vibrio cholerae serological reagents. (a) Identification....

  14. [The interrelationships between Vibrio cholerae and the infusorian Tetrahymena pyriformis].

    PubMed

    Pogorelov, V I; Pinigin, A F; Maramovich, A S; Pushkareva, V I; Litvin, V Iu; Lykova, M V; Kapustin, Iu M

    1995-01-01

    The results of the study of interaction between V. cholerae of different virulence and T. pyriformis are presented. The study has revealed the heterogeneity of V. cholerae population: alongside easily phagocytized vibrios, there are vibrios resistant to the digestive action of T. pyriformis. An increase in the number of V. cholerae in association with T. pyriformis has been evaluated, taking into account the selective multiplication of vibrios resistant to phagocytosis. The data on changes in the agglutinative, phagolytic and virulent properties of V. cholerae cultivated together with T. pyriformis are presented. The suggestion has been made that protozoa can function as hosts of pathogenic vibrios supporting their existence in water. PMID:7653129

  15. Vibrio fluvialis: an emerging human pathogen

    PubMed Central

    Ramamurthy, Thandavarayan; Chowdhury, Goutam; Pazhani, Gururaja P.; Shinoda, Sumio

    2014-01-01

    Vibrio fluvialis is a pathogen commonly found in coastal environs. Considering recent increase in numbers of diarrheal outbreaks and sporadic extraintestinal cases, V. fluvialis has been considered as an emerging pathogen. Though this pathogen can be easily isolated by existing culture methods, its identification is still a challenging problem due to close phenotypic resemblance either with Vibrio cholerae or Aeromonas spp. However, using molecular tools, it is easy to identify V. fluvialis from clinical and different environmental samples. Many putative virulence factors have been reported, but its mechanisms of pathogenesis and survival fitness in the environment are yet to be explored. This chapter covers some of the major discoveries that have been made to understand the importance of V. fluvialis. PMID:24653717

  16. Effect of water treatment on the growth potential of Vibrio cholerae and Vibrio parahaemolyticus in seawater.

    PubMed

    Wennberg, Aina Charlotte; Tryland, Ingun; Østensvik, Øyvin; Secic, Indira; Monshaugen, Marte; Liltved, Helge

    2013-02-01

    In laboratory experiments we added Vibrio cholerae and Vibrio parahaemolyticus to bottles with seawater previously treated by filtration, UV, chlorine or ozone. The purpose was to investigate the influence of different treatment techniques on the growth potential of these bacteria in simulated ballast water tanks. Residual oxidants were removed before inoculation, and the bottles were incubated at 21 ± 1 °C. The growth potential of the vibrios was investigated in two different experimental setups, i.e. in presence and absence of added natural microorganisms. In general, V. cholerae and V. parahaemolyticus rapidly lost their culturability after inoculation and storage in untreated seawater, but showed increased survival or growth in the treated water. Highest growth was observed in water previously exposed to high concentrations of ozone. Addition of natural microorganisms reduced the growth of V. cholerae and V. parahaemolyticus. PMID:23127287

  17. Molecular cloning of a C-type lectin with one carbohydrate recognition domain from Fenneropenaeus merguiensis and its expression upon challenging by pathogenic bacterium or virus.

    PubMed

    Thepnarong, Supattra; Runsaeng, Phanthipha; Rattanaporn, Onnicha; Utarabhand, Prapaporn

    2015-02-01

    Lectins, one type of pattern recognition proteins, play important roles in an innate immunity of crustaceans including shrimp. A new C-type lectin designated FmLC1 was cloned from the hepatopancreas of banana shrimp Fenneropenaeus merguiensis by procedures of PCR and 5' and 3' rapid amplification of cDNA ends (RACE). The full-length cDNA is composed of 706bp with a single open reading frame of 477bp, encoding a peptide of 158 amino acid residues. Its deduced amino acid sequence comprises a putative signal peptide of 17 amino acids and has an estimated molecular mass of 17,934Da with a theoretical pI of 4.46. The primary sequence of FmLC1 contains a single carbohydrate recognition domain (CRD) with an EPS (Glu-Pro-Ser) motif and one Ca(2+) binding site, stabilized by two disulfide bonds. FmLC1 mRNA was detected to express specifically in the hepatopancreas, a master organ in shrimp. Its expression in the hepatopancreas was up-regulated to reach the maximum at 12 or 48h following challenge of shrimp with Vibrio harveyi or white spot syndrome virus, respectively. These results suggest that FmLC1 may participate in recognition of invading pathogens such as bacteria and viruses, and play roles in the immune response of shrimp even at different stages of the clearance of pathogens. PMID:25542510

  18. Small Molecule Signaling Systems in Vibrio cholerae

    Microsoft Academic Search

    Rupak K. Bhadra; Sangita Shah; Bhabatosh Das

    \\u000a \\u000a Vibrio cholerae, the causative agent of Asiatic cholera, still remains a major public health problem in most of the developing countries.\\u000a Despite tremendous effort given in developing immunotherapeutics, availability of the whole genome sequence, and transcriptional\\u000a profiling data, still a safe, effective, and long-lasting cholera vaccine is not available. One probable reason could be that\\u000a our knowledge about stress adaptive

  19. Vibrio VopQ Induces PI3-Kinase Independent Autophagy and Antagonizes Phagocytosis

    PubMed Central

    Burdette, Dara L.; Seemann, Joachim; Orth, Kim

    2009-01-01

    Vibrio parahaemolyticus (V. para) is a Gram-negative bacterium responsible for gastroenteritis acquired from the consumption of contaminated shellfish. This bacterium harbors two type III secretion systems, one on each chromosome. The type III secretion system on chromosome I induces cell death by a temporally controlled sequence of events that is caspase independent and first involves induction of autophagy, followed by cellular rounding, and finally cellular lysis. VopQ is a type III secreted effector that is necessary for the induction of autophagy as mutant strains lacking VopQ are attenuated in their ability to induce autophagy during infection. VopQ is sufficient to induce rapid autophagy as demonstrated by microinjection of recombinant VopQ into GFP-LC3 HeLa cells. Our results demonstrate that VopQ is both necessary and sufficient for induction of autophagy during V. para-mediated cell death and this effect is independent of phosphatidylinositol-3-kinases but requires Atg5. Furthermore, induction of VopQ-mediated autophagy prevents recruitment of the necessary cellular machinery required for phagocytosis of V. para during infection. These data provide important insights into the mechanism used by V. para to cause disease. PMID:19627496

  20. The RND protein is involved in the vulnibactin export system in Vibrio vulnificus M2799.

    PubMed

    Kawano, Hiroaki; Miyamoto, Katsushiro; Yasunobe, Megumi; Murata, Masahiro; Myojin, Tomoka; Tsuchiya, Takahiro; Tanabe, Tomotaka; Funahashi, Tatsuya; Sato, Takaji; Azuma, Takashi; Mino, Yoshiki; Tsujibo, Hiroshi

    2014-10-01

    Vibrio vulnificus, an opportunistic marine bacterium that causes a serious, often fatal, infection in humans, requires iron for its pathogenesis. This bacterium exports vulnibactin for iron acquisition from the environment. The mechanisms of vulnibactin biosynthesis and ferric-vulnibactin uptake systems have recently been reported, while the vulnibactin export system has not been reported. Mutant growth under low-iron concentration conditions and a bioassay of the culture supernatant indicate that the VV1_0612 protein plays a crucial role in the vulnibactin secretion as a component of the resistance-nodulation-division (RND)-type efflux system in V. vulnificus M2799. To identify which RND protein(s) together with VV1_0612 TolC constituted the RND efflux system for vulnibactin secretion, deletion mutants of 11 RND protein-encoding genes were constructed. The growth inhibition of a multiple mutant (?11) of the RND protein-encoding genes was observed 6 h after the beginning of the culture. Furthermore, ?VV1_1681 exhibited a growth curve that was similar to that of ?11, while the multiple mutant except ?VV1_1681 showed the same growth as the wild-type strain. These results indicate that the VV1_1681 protein is involved in the vulnibactin export system of V. vulnificus M2799. This is the first genetic evidence that vulnibactin is secreted through the RND-type efflux systems in V. vulnificus. PMID:25205089

  1. Vibrio salmonicida pathogenesis analyzed by experimental challenge of Atlantic salmon (Salmo salar).

    PubMed

    Bjelland, Ane Mohn; Johansen, Renate; Brudal, Espen; Hansen, Hilde; Winther-Larsen, Hanne C; Sørum, Henning

    2012-01-01

    Cold-water vibriosis (CV) is a bacterial septicemia of farmed salmonid fish and cod caused by the Gram-negative bacterium Vibrio (Aliivibrio) salmonicida. To study the pathogenesis of this marine pathogen, Atlantic salmon was experimentally infected by immersion challenge with wild type V. salmonicida and the bacterial distribution in different organs was investigated at different time points. V. salmonicida was identified in the blood as early as 2 h after challenge demonstrating a rapid establishment of bacteremia without an initial period of colonization of the host. Two days after immersion challenge, only a few V. salmonicida were identified in the intestines, but the amount increased with time. In prolonged CV cases, V. salmonicida was the dominating bacterium of the gut microbiota causing a release of the pathogen to the water. We hypothesize that V. salmonicida uses the blood volume for proliferation during the infection of the fish and the salmonid intestine as a reservoir that favors survival and transmission. In addition, a motility-deficient V. salmonicida strain led us to investigate the impact of motility in the CV pathogenesis by comparing the virulence properties of the mutant with the wild type LFI1238 strain in both i.p. and immersion challenge experiments. V. salmonicida was shown to be highly dependent on motility to gain access to the fish host. After invasion, motility was no longer required for virulence, but the absence of normal flagellation delayed the disease development. PMID:22079881

  2. In vitro susceptibility of Vibrio spp . isolated from the environment

    Microsoft Academic Search

    S. Zanetti; T. Spanu; A. Deriu; L. Romano; L. A. Sechi; G. Fadda

    2001-01-01

    Bacteria of the genus Vibrio include harmless aquatic strains as well as strains capable of causing epidemics of cholera and human intestinal diseases. Some of these species may show resistance to different antibiotics including cefotaxime, tetracycline and chloramphenicol. The susceptibility to different antibiotics was tested using 40 Vibrio alginolitycus, eight V. parahaemolyticus and six V. vulnificus strains isolated in the

  3. Power plays: iron transport and energy transduction in pathogenic vibrios

    Microsoft Academic Search

    Ryan J. KustuschCarole; Carole J. Kuehl; Jorge H. Crosa

    2011-01-01

    The Vibrios are a unique group of bacteria inhabiting a vast array of aquatic environments. Many Vibrio species are capable of infecting a wide assortment of hosts. Some of these species include V. parahaemolyticus, V. alginolyticus, V. vulnificus, V. anguillarum, and V. cholerae. The ability of these organisms to utilize iron is essential in establishing both an infection in their

  4. ISOLATION AND DESCRIPTION OF TWO VIBRIOS PATHOGENIC TO PACIFIC

    E-print Network

    NOTES ISOLATION AND DESCRIPTION OF TWO VIBRIOS PATHOGENIC TO PACIFIC SALMON IN PUGET SOUNDPacific salmon in the marine waters of Puget Sound, Wash., and heterogeneity observed in vibrios isolated from of Pacific salmon in salt water at the NMFS Aqua- culture Experiment Station near Manchester, Wash

  5. Climate and infectious disease: use of remote sensing for detection of Vibrio cholerae by indirect measurement

    NASA Technical Reports Server (NTRS)

    Lobitz, B.; Beck, L.; Huq, A.; Wood, B.; Fuchs, G.; Faruque, A. S.; Colwell, R.

    2000-01-01

    It has long been known that cholera outbreaks can be initiated when Vibrio cholerae, the bacterium that causes cholera, is present in drinking water in sufficient numbers to constitute an infective dose, if ingested by humans. Outbreaks associated with drinking or bathing in unpurified river or brackish water may directly or indirectly depend on such conditions as water temperature, nutrient concentration, and plankton production that may be favorable for growth and reproduction of the bacterium. Although these environmental parameters have routinely been measured by using water samples collected aboard research ships, the available data sets are sparse and infrequent. Furthermore, shipboard data acquisition is both expensive and time-consuming. Interpolation to regional scales can also be problematic. Although the bacterium, V. cholerae, cannot be sensed directly, remotely sensed data can be used to infer its presence. In the study reported here, satellite data were used to monitor the timing and spread of cholera. Public domain remote sensing data for the Bay of Bengal were compared directly with cholera case data collected in Bangladesh from 1992-1995. The remote sensing data included sea surface temperature and sea surface height. It was discovered that sea surface temperature shows an annual cycle similar to the cholera case data. Sea surface height may be an indicator of incursion of plankton-laden water inland, e.g., tidal rivers, because it was also found to be correlated with cholera outbreaks. The extensive studies accomplished during the past 25 years, confirming the hypothesis that V. cholerae is autochthonous to the aquatic environment and is a commensal of zooplankton, i.e., copepods, when combined with the findings of the satellite data analyses, provide strong evidence that cholera epidemics are climate-linked.

  6. Prevalence and antimicrobial susceptibility of Vibrio parahaemolyticus isolated from retail shrimps in Malaysia.

    PubMed

    Letchumanan, Vengadesh; Yin, Wai-Fong; Lee, Learn-Han; Chan, Kok-Gan

    2015-01-01

    Vibrio parahaemolyticus is a marine and estuarine bacterium that has been the leading cause of foodborne outbreaks which leads to a significant threat to human health worldwide. Consumption of seafood contaminated with V. parahaemolyticus causes acute gastroenteritis in individuals. The bacterium poses two main virulence factor including the thermostable direct hemolysin (tdh) which is a pore-forming protein that contributes to the invasiveness of the bacterium in humans and TDH-related hemolysin (trh), which plays a similar role as tdh in the disease pathogenesis. This study aimed to investigate the antimicrobial resistance V. parahaemolyticus strains in shrimps purchased from wetmarkets and supermarkets. The toxR-based PCR assay indicated that a total of 57.8% (185/320) isolates were positive for V. parahaemolyticus. Only 10% (19/185) toxR-positive isolate exhibit the trh gene and none of the isolates were tested positive for tdh. The MAR index was measured for 14 common antimicrobial agents. The results indicated 98% of the isolates were highly susceptible to imipenem, ampicillin sulbactam (96%), chloramphenicol (95%), trimethoprim-sulfamethoxazole (93%), gentamicin (85%), levofloxacin (83%), and tetracycline (82%). The chloramphenicol (catA2) and kanamycin (aphA-3) resistance genes were detected in the resistant V. parahaemolyticus isolates. Our results demonstrate that shrimps are contaminated with V. parahaemolyticus, some of which carry the trh-gene thus being potential to cause food borne illness. The occurrence of multidrug resistance strains in the environment could be an indication of excessive usage of antibiotics in agriculture and aquaculture fields. PMID:25688239

  7. Prevalence and antimicrobial susceptibility of Vibrio parahaemolyticus isolated from retail shrimps in Malaysia

    PubMed Central

    Letchumanan, Vengadesh; Yin, Wai-Fong; Lee, Learn-Han; Chan, Kok-Gan

    2015-01-01

    Vibrio parahaemolyticus is a marine and estuarine bacterium that has been the leading cause of foodborne outbreaks which leads to a significant threat to human health worldwide. Consumption of seafood contaminated with V. parahaemolyticus causes acute gastroenteritis in individuals. The bacterium poses two main virulence factor including the thermostable direct hemolysin (tdh) which is a pore-forming protein that contributes to the invasiveness of the bacterium in humans and TDH-related hemolysin (trh), which plays a similar role as tdh in the disease pathogenesis. This study aimed to investigate the antimicrobial resistance V. parahaemolyticus strains in shrimps purchased from wetmarkets and supermarkets. The toxR-based PCR assay indicated that a total of 57.8% (185/320) isolates were positive for V. parahaemolyticus. Only 10% (19/185) toxR-positive isolate exhibit the trh gene and none of the isolates were tested positive for tdh. The MAR index was measured for 14 common antimicrobial agents. The results indicated 98% of the isolates were highly susceptible to imipenem, ampicillin sulbactam (96%), chloramphenicol (95%), trimethoprim-sulfamethoxazole (93%), gentamicin (85%), levofloxacin (83%), and tetracycline (82%). The chloramphenicol (catA2) and kanamycin (aphA-3) resistance genes were detected in the resistant V. parahaemolyticus isolates. Our results demonstrate that shrimps are contaminated with V. parahaemolyticus, some of which carry the trh-gene thus being potential to cause food borne illness. The occurrence of multidrug resistance strains in the environment could be an indication of excessive usage of antibiotics in agriculture and aquaculture fields. PMID:25688239

  8. Vibrio diversity and dynamics in the Monterey Bay upwelling region.

    PubMed

    Mansergh, Sarah; Zehr, Jonathan P

    2014-01-01

    The Vibrionaceae (Vibrio) are a ubiquitous group of metabolically flexible marine bacteria that play important roles in biogeochemical cycling in the ocean. Despite this versatility, little is known about Vibrio diversity and abundances in upwelling regions. The seasonal dynamics of Vibrio populations was examined by analysis of 16S rRNA genes in Monterey Bay (MB), California from April 2006-April 2008 at two long term monitoring stations, C1 and M2. Vibrio phylotypes within MB were diverse, with subpopulations clustering with several different cultured representatives including Allivibrio spp., Vibrio penaecida, and Vibrio splendidus as well as with many unidentified marine environmental bacterial 16S rRNA gene sequences. Total Vibrio population abundances, as well as abundances of a Vibrio sp. subpopulation (MBAY Vib7) and an Allivibrio sp. subpopulation (MBAY Vib4) were examined in the context of environmental parameters from mooring station and CTD cast data. Total Vibrio populations showed some seasonal variability but greater variability was observed within the two subpopulations. MBAY Vib4 was negatively associated with MB upwelling indices and positively correlated with oceanic season conditions, when upwelling winds relax and warmer surface waters are present in MB. MBAY Vib7 was also negatively associated with upwelling indices and represented a deeper Vibrio sp. population. Correlation patterns suggest that larger oceanographic conditions affect the dynamics of the populations in MB, rather than specific environmental factors. This study is the first to target and describe the diversity and dynamics of these natural populations in MB and demonstrates that these populations shift seasonally within the region. PMID:24575086

  9. Light?scattering sensor for real?time identification of Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholerae colonies on solid agar plate

    PubMed Central

    Huff, Karleigh; Aroonnual, Amornrat; Littlejohn, Amy E. Fleishman; Rajwa, Bartek; Bae, Euiwon; Banada, Padmapriya P.; Patsekin, Valery; Hirleman, E. Daniel; Robinson, J. Paul; Richards, Gary P.; Bhunia, Arun K.

    2012-01-01

    Summary The three most common pathogenic species of Vibrio, Vibrio cholerae, Vibrio parahaemolyticus and Vibrio vulnificus, are of major concerns due to increased incidence of water? and seafood?related outbreaks and illness worldwide. Current methods are lengthy and require biochemical and molecular confirmation. A novel label?free forward light?scattering sensor was developed to detect and identify colonies of these three pathogens in real time in the presence of other vibrios in food or water samples. Vibrio colonies grown on agar plates were illuminated by a 635?nm laser beam and scatter?image signatures were acquired using a CCD (charge?coupled device) camera in an automated BARDOT (BActerial Rapid Detection using Optical light?scattering Technology) system. Although a limited number of Vibrio species was tested, each produced a unique light?scattering signature that is consistent from colony to colony. Subsequently a pattern recognition system analysing the collected light?scatter information provided classification in 1?2?min with an accuracy of 99%. The light?scattering signatures were unaffected by subjecting the bacteria to physiological stressors: osmotic imbalance, acid, heat and recovery from a viable but non?culturable state. Furthermore, employing a standard sample enrichment in alkaline peptone water for 6?h followed by plating on selective thiosulphate citrate bile salts sucrose agar at 30°C for ??12?h, the light?scattering sensor successfully detected V.?cholerae, V.?parahaemolyticus and V.?vulnificus present in oyster or water samples in 18?h even in the presence of other vibrios or other bacteria, indicating the suitability of the sensor as a powerful screening tool for pathogens on agar plates. PMID:22613192

  10. Localization of Vibrio cholerae O1 in the intestinal tissue.

    PubMed

    Sincharoenkul, R; Chaicumpa, W; Pongponratn, E; Limpananont, J; Tapchaisri, P; Kalambaheti, T; Chongsa-nguan, M

    1993-12-01

    Colonization of V. cholerae O1 in vivo is known to be a non-invasive type which the vibrios are confined only to the intestinal tissues. The pathway by which the vibrio antigens reach the lymphoid cells and subsequently give rise to the immune responses is not entirely clear. Thus, experiments were performed in experimental rats by inoculating live V. cholerae O1 into the ligated ileal loops. The fate of the vibrios in the intestinal tissues was then studied by transmission electron microscopy at different times after the inoculation. It was concluded that live V. cholerae O1 were initially taken up by the M cells which overlay Peyer's patches and which subsequently delivered the intact vibrios to phagocytic cells in the Peyer's patches. These phagocytic cells processed (digested) the vibrios while the lymphocytes and plasma cells infiltrated around them. During the late period of infection (12-15 hours after inoculation of the vibrios), vibrios were also found passing through the loose intercellular spaces between the absorptive epithelial cells into the underlying intestinal tissues. PMID:8080608

  11. Sequence Determination of rRNA Genes of Pathogenic Vibrio Species and Whole-Cell Identification of Vibrio vulni'jicus with rRNA-Targeted Oligonucleotide Probes

    Microsoft Academic Search

    R. AZNAR; W. LUDWIG; R. I. AMANN; K. H. SCHLEIFER

    1994-01-01

    A comparative analysis of seven new 16s rRNA gene sequences of pathogenic I\\/ibrio species with previously published vibrio sequences confirmed that Vibrio vulnificus represents a group that is not closely related to the core organisms of the genus Vibrio. In addition, we found that K vulnijicus, Listonella (Vibrio) anguillarum and I\\/ibrio diazotrophicus branch off separately from the core group. A

  12. Geovibrio ferrireducens, a phylogenetically distinct dissimilatory Fe(III)-reducing bacterium

    USGS Publications Warehouse

    Caccavo, F., Jr.; Coates, J.D.; Rossello-Mora, R. A.; Ludwig, W.; Schleifer, K.H.; Lovley, D.R.; McInerney, M.J.

    1996-01-01

    A new, phylogenetically distinct, dissimilatory, Fe(III)-reducing bacterium was isolated from surface sediment of a hydrocarbon-contaminated ditch. The isolate, designated strain PAL-1, was an obligately anaerobic, non-fermentative, motile, gram-negative vibrio. PAL-1 grew in a defined medium with acetate as electron donor and ferric pyrophosphate, ferric oxyhydroxide, ferric citrate, Co(III)-EDTA, or elemental sulfur as sole electron acceptor. PAL-1 also used proline, hydrogen, lactate, propionate, succinate, fumarate, pyruvate, or yeast extract as electron donors for Fe(III) reduction. It is the first bacterium known to couple the oxidation of an amino acid to Fe(III) reduction. PAI-1 did not reduce oxygen, Mn(IV), U(VI), Cr(VI), nitrate, sulfate, sulfite, or thiosulfate with acetate as the electron donor. Cell suspensions of PAL-1 exhibited dithionite-reduced minus air-oxidized difference spectra that were characteristic of c-type cytochromes. Analysis of the 16S rRNA gene sequence of PAL-1 showed that the strain is not related to any of the described metal-reducing bacteria in the Proteobacteria and, together with Flexistipes sinusarabici, forms a separate line of descent within the Bacteria. Phenotypically and phylogenetically, strain PAI-1 differs from all other described bacteria, and represents the type strain of a new genus and species. Geovibrio ferrireducens.

  13. Photobacterium damselae subsp. damselae, a bacterium pathogenic for marine animals and humans

    PubMed Central

    Rivas, Amable J.; Lemos, Manuel L.; Osorio, Carlos R.

    2013-01-01

    Photobacterium damselae subsp. damselae (formerly Vibrio damsela) is a pathogen of a variety of marine animals including fish, crustaceans, molluscs, and cetaceans. In humans, it can cause opportunistic infections that may evolve into necrotizing fasciitis with fatal outcome. Although the genetic basis of virulence in this bacterium is not completely elucidated, recent findings demonstrate that the phospholipase-D Dly (damselysin) and the pore-forming toxins HlyApl and HlyAch play a main role in virulence for homeotherms and poikilotherms. The acquisition of the virulence plasmid pPHDD1 that encodes Dly and HlyApl has likely constituted a main driving force in the evolution of a highly hemolytic lineage within the subspecies. Interestingly, strains that naturally lack pPHDD1 show a strong pathogenic potential for a variety of fish species, indicating the existence of yet uncharacterized virulence factors. Future and deep analysis of the complete genome sequence of Photobacterium damselae subsp. damselae will surely provide a clearer picture of the virulence factors employed by this bacterium to cause disease in such a varied range of hosts. PMID:24093021

  14. Cloning and Nucleotide Sequence of the gyrB Gene of Vibrio parahaemolyticus and Its Application in Detection of This Pathogen in Shrimp

    PubMed Central

    Venkateswaran, Kasthuri; Dohmoto, Nobuhiko; Harayama, Shigeaki

    1998-01-01

    Because biochemical testing and 16S rRNA sequence analysis have proven inadequate for the differentiation of Vibrio parahaemolyticus from closely related species, we employed the gyrase B gene (gyrB) as a molecular diagnostic probe. The gyrB genes of V. parahaemolyticus and closely related Vibrio alginolyticus were cloned and sequenced. Oligonucleotide PCR primers were designed for the amplification of a 285-bp fragment from within gyrB specific for V. parahaemolyticus. These primers recognized 117 of 117 reference and wild-type V. parahaemolyticus strains, whereas amplification did not occur when 90 strains of 37 other Vibrio species or 60 strains representing 34 different nonvibrio species were tested. In 100-?l PCR mixtures, the lower detection limits were 5 CFU for live cells and 4 pg for purified DNA. The possible application of gyrB primers for the routine identification of V. parahaemolyticus in food was examined. We developed and tested a procedure for the specific detection of the target organism in shrimp consisting of an 18-h preenrichment followed by PCR amplification of the 285-bp V. parahaemolyticus-specific fragment. This method enabled us to detect an initial inoculum of 1.5 CFU of V. parahaemolyticus cells per g of shrimp homogenate. By this approach, we were able to detect V. parahaemolyticus in all of 27 shrimp samples artificially inoculated with this bacterium. We present here a rapid, reliable, and sensitive protocol for the detection of V. parahaemolyticus in shrimp. PMID:9464408

  15. Glucose- but Not Rice-Based Oral Rehydration Therapy Enhances the Production of Virulence Determinants in the Human Pathogen Vibrio cholerae

    PubMed Central

    Kühn, Juliane; Finger, Flavio; Bertuzzo, Enrico; Borgeaud, Sandrine; Gatto, Marino; Rinaldo, Andrea; Blokesch, Melanie

    2014-01-01

    Despite major attempts to prevent cholera transmission, millions of people worldwide still must address this devastating disease. Cholera research has so far mainly focused on the causative agent, the bacterium Vibrio cholerae, or on disease treatment, but rarely were results from both fields interconnected. Indeed, the treatment of this severe diarrheal disease is mostly accomplished by oral rehydration therapy (ORT), whereby water and electrolytes are replenished. Commonly distributed oral rehydration salts also contain glucose. Here, we analyzed the effects of glucose and alternative carbon sources on the production of virulence determinants in the causative agent of cholera, the bacterium Vibrio cholerae during in vitro experimentation. We demonstrate that virulence gene expression and the production of cholera toxin are enhanced in the presence of glucose or similarly transported sugars in a ToxR-, TcpP- and ToxT-dependent manner. The virulence genes were significantly less expressed if alternative non-PTS carbon sources, including rice-based starch, were utilized. Notably, even though glucose-based ORT is commonly used, field studies indicated that rice-based ORT performs better. We therefore used a spatially explicit epidemiological model to demonstrate that the better performing rice-based ORT could have a significant impact on epidemic progression based on the recent outbreak of cholera in Haiti. Our results strongly support a change of carbon source for the treatment of cholera, especially in epidemic settings. PMID:25474211

  16. Immune response in Lutjanus erythropterus induced by the major outer membrane protein (OmpU) of Vibrio alginolyticus.

    PubMed

    Cai, Shuang-Hu; Yaol, Shao-Yun; Lu, Yi-Shan; Wu, Zao-He; Jian, Ji-Chang; Wang, Bei

    2010-05-18

    The outer membrane proteins (OMPs) of the marine aquatic animal pathogen Vibrio alginolyticus play an important role in the virulence of the bacterium and are potential candidates for vaccine development. In this study, the major 35.6 kDa OMP of V. alginolyticus was isolated by gel excision from the crude OMP fraction from V. alginolyticus. The sequence of the first 27 amino acid residues from the N-terminal end of the protein is ATV YKD GGT ELL VGG RVE FRG DFI GSD, which has high homology with OmpU proteins from other Vibrio spp. (92%). Lutjanus erythropterus were vaccinated with OmpU, and immunogenicity was confirmed by subsequent western blotting. Enzyme-linked immunosorbent assay (ELISA) analysis demonstrated that OmpU produced an observable antibody response in all sera of the vaccinated fish. L. erythropterus vaccinated with OmpU produced specific antibodies, and were highly resistant to infection with virulent V. alginolyticus. These results indicate that OmpU is an effective vaccine candidate against V. alginolyticus for L. erythropterus. PMID:20597431

  17. Anti-lipopolysaccharide factors in the American lobster Homarus americanus: molecular characterization and transcriptional response to Vibrio fluvialis challenge.

    PubMed

    Beale, K M; Towle, D W; Jayasundara, N; Smith, C M; Shields, J D; Small, H J; Greenwood, S J

    2008-12-01

    Two partial mRNA sequences predicted to encode anti-lipopolysaccharide factors (ALFs) were identified among expressed sequence tags generated from the American lobster Homarus americanus and complete cDNA sequences were obtained from library clones. Comparison of the translated amino acid sequences to those publicly available confirmed similarity to arthropod anti-lipopolysaccharide factors. Both protein sequences, designated ALFHa-1 and ALFHa-2, contained an N-terminal signal peptide and two half-cysteines participating in a disulfide bridge, features conserved in other ALFs. Predicted secondary structures were similar to that described for the ALF from the horseshoe crab Limulus polyphemus. As part of an exploratory study of immunity in H. americanus, lobsters were injected with the bacterium Vibrio fluvialis and gill, hematopoietic, and hepatopancreas tissues were sampled for analysis of gene expression of ALFHa-1 and ALFHa-2 by quantitative PCR. The relative abundance of ALFHa-2 mRNA was not significantly affected by Vibrio injection in any of the three tissues tested. In contrast, ALFHa-1 mRNA levels in gills were increased by the treatment some 17-fold. Our results support a molecularly specific regulation of antimicrobial proteins in response to bacterial infection in H. americanus. PMID:19956341

  18. Calcium promotes exopolysaccharide phase variation and biofilm formation of the resulting phase variants in the human pathogen Vibrio vulnificus.

    PubMed

    Garrison-Schilling, Katherine L; Grau, Brenda L; McCarter, Kevin S; Olivier, Brett J; Comeaux, Nicole E; Pettis, Gregg S

    2011-03-01

    Vibrio vulnificus is a Gram-negative bacterium found in estuaries and coastal waters and is associated with human disease caused by ingestion of raw shellfish. Pathogenesis is directly related to the presence of capsular polysaccharide (CPS). Encapsulated virulent strains exhibit an opaque colony phenotype, while unencapsulated attenuated strains appear translucent. A third colony type, rugose, is caused by expression of rugose extracellular polysaccharide (rEPS) and forms robust biofilms. Vibrio vulnificus undergoes phase variation associated with altered levels of CPS and rEPS, and we show here that calcium (Ca²(+) ) significantly increases the rate of CPS and rEPS phase variation in this species. Interestingly, multiple phenotypic responses to increased [Ca²(+) ] were observed among strains, which suggests the existence of underlying cognate genetic or epigenetic differences. Certain translucent isolates contained deletions at the group I CPS operon, inferring increased [Ca²(+) ] upregulates existing phase variation mechanisms. Expanding on a previous observation (Kierek and Watnick, Proc. Natl. Acad. Sci. USA 100: 14357-14362, 2003), increased [Ca²(+) ] also enhanced biofilm formation for all phase variants. Our results show that Ca²(+) promotes both polysaccharide phase variation and biofilm formation of the resulting phase variants, thereby likely serving a dual role in persistence of V. vulnificus in the environment. PMID:21059165

  19. Anti-lipopolysaccharide factors in the American lobster Homarus americanus: Molecular characterization and transcriptional response to Vibrio fluvialis challenge

    PubMed Central

    Beale, K.M.; Towle, D.W.; Jayasundara, N.; Smith, C.M.; Shields, J.D.; Small, H.J.; Greenwood, S.J.

    2008-01-01

    Two partial mRNA sequences predicted to encode anti-lipopolysaccharide factors (ALFs) were identified among expressed sequence tags generated from the American lobster Homarus americanus and complete cDNA sequences were obtained from library clones. Comparison of the translated amino acid sequences to those publicly available confirmed similarity to arthropod anti-lipopolysaccharide factors. Both protein sequences, designated ALFHa-1 and ALFHa-2, contained an N-terminal signal peptide and two half-cysteines participating in a disulfide bridge, features conserved in other ALFs. Predicted secondary structures were similar to that described for the ALF from the horseshoe crab Limulus polyphemus. As part of an exploratory study of immunity in H. americanus, lobsters were injected with the bacterium Vibrio fluvialis and gill, hematopoietic, and hepatopancreas tissues were sampled for analysis of gene expression of ALFHa-1 and ALFHa-2 by quantitative PCR. The relative abundance of ALFHa-2 mRNA was not significantly affected by Vibrio injection in any of the three tissues tested. In contrast, ALFHa-1 mRNA levels in gills were increased by the treatment some 17-fold. Our results support a molecularly specific regulation of antimicrobial proteins in response to bacterial infection in H. americanus. PMID:19956341

  20. Expression of Vibrio salmonicida virulence genes and immune response parameters in experimentally challenged Atlantic salmon (Salmo salar L.)

    PubMed Central

    Bjelland, Ane M.; Fauske, Aud K.; Nguyen, Anh; Orlien, Ingvild E.; Østgaard, Ingrid M.; Sørum, Henning

    2013-01-01

    The Gram-negative bacterium Vibrio salmonicida is the causative agent of cold-water vibriosis (CV), a hemorrhagic septicemia that primarily affects farmed Atlantic salmon (Salmo salar L.). The mechanisms of disease development, host specificity and adaptation, as well as the immunogenic properties of V. salmonicida are largely unknown. Therefore, to gain more knowledge on the pathogenesis of CV, 90 Atlantic salmon parr were injected intraperitoneally with 6 × 106 CFU of V. salmonicida LFI1238. Samples from blood and spleen tissue were taken at different time points throughout the challenge for gene expression analysis by two-step reverse transcription (RT) quantitative real-time polymerase chain reaction. Out of a panel of six housekeeping genes, accD, gapA, and 16S rDNA were found to be the most suitable references for expression analysis in Vibrio salmonicida. The bacterial proliferation during challenge was monitored based on the expression of the 16S rRNA encoding gene. Before day 4, the concentrations of V. salmonicida in blood and spleen tissue demonstrated a lag phase. From day 4, the bacterial proliferation was exponential. The expression profiles of eight genes encoding potential virulence factors of V. salmonicida were studied. Surprisingly, all tested virulence genes were generally highest expressed in broth cultures compared to the in vivo samples. We hypothesize that this general muting of gene expression in vivo may be a strategy for V. salmonicida to hide from the host immune system. To further investigate this hypothesis, the expression profiles of eight genes encoding innate immune factors were analyzed. The results demonstrated a strong and rapid, but short-lasting innate immune response against V. salmonicida. These results suggest that the bacterium possesses mechanisms that inhibit and/or resist the salmon innate immune system until the host becomes exhausted of fighting the on-going and eventually overwhelming infection. PMID:24391635

  1. Expression of Vibrio salmonicida virulence genes and immune response parameters in experimentally challenged Atlantic salmon (Salmo salar L.).

    PubMed

    Bjelland, Ane M; Fauske, Aud K; Nguyen, Anh; Orlien, Ingvild E; Ostgaard, Ingrid M; Sørum, Henning

    2013-01-01

    The Gram-negative bacterium Vibrio salmonicida is the causative agent of cold-water vibriosis (CV), a hemorrhagic septicemia that primarily affects farmed Atlantic salmon (Salmo salar L.). The mechanisms of disease development, host specificity and adaptation, as well as the immunogenic properties of V. salmonicida are largely unknown. Therefore, to gain more knowledge on the pathogenesis of CV, 90 Atlantic salmon parr were injected intraperitoneally with 6 × 10(6) CFU of V. salmonicida LFI1238. Samples from blood and spleen tissue were taken at different time points throughout the challenge for gene expression analysis by two-step reverse transcription (RT) quantitative real-time polymerase chain reaction. Out of a panel of six housekeeping genes, accD, gapA, and 16S rDNA were found to be the most suitable references for expression analysis in Vibrio salmonicida. The bacterial proliferation during challenge was monitored based on the expression of the 16S rRNA encoding gene. Before day 4, the concentrations of V. salmonicida in blood and spleen tissue demonstrated a lag phase. From day 4, the bacterial proliferation was exponential. The expression profiles of eight genes encoding potential virulence factors of V. salmonicida were studied. Surprisingly, all tested virulence genes were generally highest expressed in broth cultures compared to the in vivo samples. We hypothesize that this general muting of gene expression in vivo may be a strategy for V. salmonicida to hide from the host immune system. To further investigate this hypothesis, the expression profiles of eight genes encoding innate immune factors were analyzed. The results demonstrated a strong and rapid, but short-lasting innate immune response against V. salmonicida. These results suggest that the bacterium possesses mechanisms that inhibit and/or resist the salmon innate immune system until the host becomes exhausted of fighting the on-going and eventually overwhelming infection. PMID:24391635

  2. Toxic Proteins from Vibrio cholerae and Water Vibrios which are Lethal for Mice

    Microsoft Academic Search

    C. R. JENKIN; D. ROWLEY

    1959-01-01

    SUMMARY: A toxic protein has been isolated from Inaba and Ogawa strains of Vibm'o cholmae and from water vibrios by dissolving the bacteria in 2.5~-urea and subsequent fractional precipitation with ammonium sulphate. This toxic protein accounted for the major portion of the toxicity of whole organism. Immunological and chemical data suggest that the toxic protein is the protein component of

  3. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...are used in the agglutination (an antigen-antibody clumping reaction) test to identify Vibrio cholerae from cultured isolates...characterized by severe diarrhea with extreme fluid and electrolyte (salts) depletion, and by vomiting, muscle cramps, and...

  4. Interactions between Mytilus galloprovincialis hemocytes and the bivalve pathogens Vibrio aestuarianus 01/032 and Vibrio splendidus LGP32.

    PubMed

    Balbi, T; Fabbri, R; Cortese, K; Smerilli, A; Ciacci, C; Grande, C; Vezzulli, L; Pruzzo, C; Canesi, L

    2013-12-01

    Marine bivalves can accumulate large numbers of bacteria, in particular Vibrio species, whose persistence in bivalve tissues largely depends on their sensitivity to the bactericidal activity of circulating hemocytes and hemolymph soluble factors. The interactions between vibrios and hemolymph have been investigated, in particular in bivalve species susceptible to infection by certain Vibrio spp. and strains. In this work, the effects of two bivalve pathogens, Vibrio splendidus LGP32 (V.s.) and Vibrio aestuarianus 01/032 (V.a.), isolated from oyster mortality outbreaks, on the hemocytes of Mytilus galloprovincialis were investigated. In vitro, V.s., but not V.a., induced a dramatic decrease in lysosomal membrane stability-LMS in the hemocytes; both vibrios induced a moderate lysozyme release, with V.s. > V.a.. The V.s.-induced decrease in LMS was mediated by activation of PI-3Kinase, as shown by use of different kinase inhibitors. TEM analysis showed rapid internalization of both vibrios; however, V.s. lead to cellular and lysosomal damage and was able to survive within the hemocytes, whereas significant killing of V.a. was observed. In vivo, in mussels challenged with either vibrio and sampled at 6, 24 and 96 h post-injection, transient decreases in hemocyte LMS and progressive increases in serum lysozyme activity were observed, with V.s. > V.a.. Moreover, whereas V.a. was efficiently cleared from hemolymph, V.s. showed significant growth, that was maximal at 24 h p.i. when lowest LMS values were recorded in the hemocytes. Both vibrios also induced significant decreases in LMS in the digestive gland, again with V.s. > V.a.. The results indicate distinct interactions between mussel hemocytes and the two vibrio strains tested. The effects of V.s. may be due to the capacity of this strain to interfere with the signaling pathways involved in hemocyte function, thus escaping the bactericidal activity of the host cell, as observed for certain mammalian pathogens. Although V.s. is considered not pathogenic to Mytilus, this vibrio strain can affect the lysosomal function at the cellular and tissue level, thus leading to stressful conditions. PMID:24080469

  5. Viscosity dictates metabolic activity of Vibrio ruber

    PubMed Central

    Bori?, Maja; Danev?i?, Tjaša; Stopar, David

    2012-01-01

    Little is known about metabolic activity of bacteria, when viscosity of their environment changes. In this work, bacterial metabolic activity in media with viscosity ranging from 0.8 to 29.4 mPas was studied. Viscosities up to 2.4 mPas did not affect metabolic activity of Vibrio ruber. On the other hand, at 29.4 mPas respiration rate and total dehydrogenase activity increased 8 and 4-fold, respectively. The activity of glucose-6-phosphate dehydrogenase (GPD) increased up to 13-fold at higher viscosities. However, intensified metabolic activity did not result in faster growth rate. Increased viscosity delayed the onset as well as the duration of biosynthesis of prodigiosin. As an adaptation to viscous environment V. ruber increased metabolic flux through the pentose phosphate pathway and reduced synthesis of a secondary metabolite. In addition, V. ruber was able to modify the viscosity of its environment. PMID:22826705

  6. Transformation of Vibrio cholerae by plasmid DNA.

    PubMed

    Panda, D K; Dasgupta, U; Das, J

    1991-08-30

    The lack of an efficient transformation system in Vibrio cholerae was a handicap in the genetic manipulation of this important human pathogen. Since V. cholerae cells secrete DNases, this may interfere with the uptake of DNA. The present report describes the approaches taken for transforming V. cholerae cells with plasmid DNA, by overcoming this DNase barrier. The partial success of transforming DNase-negative mutants confirmed the role of DNase in the nontransformability of the wild-type cells. Successful transformation was carried out following removal of DNases from the periplasmic space. This was achieved by treating the cells with Mg2+ and Ca2+ ions to allow the DNase to be released, and then holding them under conditions where the remaining DNase activity was minimized before adding DNA to the competent cells. Transformation efficiencies of the order of 10(-5) per recipient cell were observed. PMID:1936999

  7. Alterations in the Proteome of the Euprymna scolopes Light Organ in Response to Symbiotic Vibrio fischeri

    PubMed Central

    Doino Lemus, Judith; McFall-Ngai, Margaret J.

    2000-01-01

    During the onset of the cooperative association between the Hawaiian sepiolid squid Euprymna scolopes and the marine luminous bacterium Vibrio fischeri, the anatomy and morphology of the host's symbiotic organ undergo dramatic changes that require interaction with the bacteria. This morphogenetic process involves an array of tissues, including those in direct contact with, as well as those remote from, the symbiotic bacteria. The bacteria induce the developmental program soon after colonization of the organ, although complete morphogenesis requires 96 h. In this study, to determine critical time points, we examined the biochemistry underlying bacterium-induced host development using two-dimensional polyacrylamide gel electrophoresis. Specifically, V. fischeri-induced changes in the soluble proteome of the symbiotic organ during the first 96 h of symbiosis were identified by comparing the protein profiles of symbiont-colonized and uncolonized organs. Both symbiosis-related changes and age-related changes were analyzed to determine what proportion of the differences in the proteomes was the result of specific responses to interaction with bacteria. Although no differences were detected over the first 24 h, numerous symbiosis-related changes became apparent at 48 and 96 h and were more abundant than age-related changes. In addition, many age-related protein changes occurred 48 h sooner in symbiotic animals, suggesting that the interaction of squid tissue with V. fischeri cells accelerates certain developmental processes of the symbiotic organ. These data suggest that V. fischeri-induced modifications in host tissues that occur in the first 24 h of the symbiosis are independent of marked alterations in the patterns of abundant proteins but that the full 4-day morphogenetic program requires significant alteration of the host soluble proteome. PMID:10966433

  8. Integration of a laterally acquired gene into a cell network important for growth in a strain of Vibrio rotiferianus

    PubMed Central

    2011-01-01

    Background Lateral Gene Transfer (LGT) is a major contributor to bacterial evolution and up to 25% of a bacterium's genome may have been acquired by this process over evolutionary periods of time. Successful LGT requires both the physical transfer of DNA and its successful incorporation into the host cell. One system that contributes to this latter step by site-specific recombination is the integron. Integrons are found in many diverse bacterial Genera and is a genetic system ubiquitous in vibrios that captures mobile DNA at a dedicated site. The presence of integron-associated genes, contained within units of mobile DNA called gene cassettes makes up a substantial component of the vibrio genome (1-3%). Little is known about the role of this system since the vast majority of genes in vibrio arrays are highly novel and functions cannot be ascribed. It is generally regarded that strain-specific mobile genes cannot be readily integrated into the cellular machinery since any perturbation of core metabolism is likely to result in a loss of fitness. Results In this study, at least one mobile gene contained within the Vibrio rotiferianus strain DAT722, but lacking close relatives elsewhere, is shown to greatly reduce host fitness when deleted and tested in growth assays. The precise role of the mobile gene product is unknown but impacts on the regulation of outermembrane porins. This demonstrates that strain specific laterally acquired mobile DNA can be integrated rapidly into bacterial networks such that it becomes advantageous for survival and adaptation in changing environments. Conclusions Mobile genes that are highly strain specific are generally believed to act in isolation. This is because perturbation of existing cell machinery by the acquisition of a new gene by LGT is highly likely to lower fitness. In contrast, we show here that at least one mobile gene, apparently unique to a strain, encodes a product that has integrated into central cellular metabolic processes such that it greatly lowers fitness when lost under those conditions likely to be commonly encountered for the free living cell. This has ramifications for our understanding of the role mobile gene encoded products play in the cell from a systems biology perspective. PMID:22093957

  9. Intracellular Vibrio parahaemolyticus Escapes the Vacuole and Establishes a Replicative Niche in the Cytosol of Epithelial Cells

    PubMed Central

    de Souza Santos, Marcela

    2014-01-01

    ABSTRACT Vibrio parahaemolyticus is a globally disseminated Gram-negative marine bacterium and the leading cause of seafood-borne acute gastroenteritis. Pathogenic bacterial isolates encode two type III secretion systems (T3SS), with the second system (T3SS2) considered the main virulence factor in mammalian hosts. For many decades, V. parahaemolyticus has been studied as an exclusively extracellular bacterium. However, the recent characterization of the T3SS2 effector protein VopC has suggested that this pathogen has the ability to invade, survive, and replicate within epithelial cells. Herein, we characterize this intracellular lifestyle in detail. We show that following internalization, V. parahaemolyticus is contained in vacuoles that develop into early endosomes, which subsequently mature into late endosomes. V. parahaemolyticus then escapes into the cytoplasm prior to vacuolar fusion with lysosomes. Vacuolar acidification is an important trigger for this escape. The cytoplasm serves as the pathogen’s primary intracellular replicative niche; cytosolic replication is rapid and robust, with cells often containing over 150 bacteria by the time of cell lysis. These results show how V. parahaemolyticus successfully establishes an intracellular lifestyle that could contribute to its survival and dissemination during infection. PMID:25205094

  10. Protection and Attachment of Vibrio cholerae Mediated by the Toxin-Coregulated Pilus in the Infant Mouse Model?†

    PubMed Central

    Krebs, Shelly J.; Taylor, Ronald K.

    2011-01-01

    Colonization of the human small intestine by Vibrio cholerae is an essential step in pathogenesis that requires the type IV toxin-coregulated pilus (TCP). To date, three functions of TCP have been characterized: it serves as the CTX? receptor, secretes the colonization factor TcpF, and functions in microcolony formation by mediating bacterium-bacterium interactions. Although type IV pili in other pathogenic bacteria have been characterized as playing a major role in attachment to epithelial cells, there are very few studies to suggest that TCP acts as an attachment factor. Taking this into consideration, we investigated the function of TCP in attachment to Caco-2 cells and found that mutants lacking TCP were defective in attachment compared to the wild type. Overexpression of ToxT, the activator of TCP, significantly increased attachment of wild-type V. cholerae to Caco-2 cells. Using field-emission scanning electron microscopy (FESEM), we also observed TCP-mediated attachment to the small intestines of infected infant mice by using antibodies specific to TCP and V. cholerae. Remarkably, we also visualized matrices comprised of TCP appearing to engulf V. cholerae during infection, and we demonstrated that these matrices protected the bacteria from a component of bile, disclosing a possible new role of this pilus in protection of the bacterial cells from antimicrobial agents. This study provides new insights into TCP's function in V. cholerae colonization of the small intestine, describing additional roles in mediating attachment and protection of V. cholerae bacterial cells. PMID:21804008

  11. Role of polyphosphate kinase gene (ppk) for survival of Vibrio cholerae O1 in surface water of Bangladesh.

    PubMed

    Jahid, Iqbal Kabir; Hasan, Md Mahmud; Abdul Matin, Mohammad; Mahmud, Zahid Hayat; Neogi, Sucharit Basu; Uddin, Md Hafiz; Islam, Md Sirajul

    2013-11-15

    Polyphosphate provides a substitute for ATP and energy source when phosphorus is a limiting resource in nature. The present study focuses on the role ofpolyphosphate for the survival of Vibrio cholerae in the aquatic habitats as an autochthonous bacterium. The survival advantages of polyphosphate of V. cholerae O1 having (wild type) and lacking (mutant) polyphosphate kinase (ppk) gene in surface water and with Anabaena variabilis were compared by cultural, Direct Fluorescent Antibody (DFA) and polymerase chain reaction methods in natural water microcosms. The microcosm's water was prepared by filtering and physicochemical parameters were also investigated by standard methods. The results revealed that both fresh and saline water, the wild type strain enhanced survival in cultural conditioned than ppk mutant strain. However, Fluorescent Antibody Direct Viable Counts (FADVC) and Polymerase Chain Reaction (PCR) results noted both strains have the equal survival strategy in viable but nonculturable state (VNC). In conclusion, it could be hypothesized that the polyphosphate inclusion body might keep cultivable and survivable at low phosphate natural environment of the aquatic bacterium. PMID:24511696

  12. Manipulation of intestinal epithelial cell function by the cell contact-dependent type III secretion systems of Vibrio parahaemolyticus

    PubMed Central

    O'Boyle, Nicky; Boyd, Aoife

    2013-01-01

    Vibrio parahaemolyticus elicits gastroenteritis by deploying Type III Secretion Systems (TTSS) to deliver effector proteins into epithelial cells of the human intestinal tract. The bacteria must adhere to the human cells to allow colonization and operation of the TTSS translocation apparatus bridging the bacterium and the host cell. This article first reviews recent advances in identifying the molecules responsible for intercellular adherence. V. parahaemolyticus possesses two TTSS, each of which delivers an exclusive set of effectors and mediates unique effects on the host cell. TTSS effectors primarily target and alter the activation status of host cell signaling proteins, thereby bringing about changes in the regulation of cellular behavior. TTSS1 is responsible for the cytotoxicity of V. parahaemolyticus, while TTSS2 is necessary for the enterotoxicity of the pathogen. Recent publications have elucidated the function of several TTSS effectors and their importance in the virulence of the bacterium. This review will explore the ability of the TTSS to manipulate activities of human intestinal cells and how this modification of cell function favors bacterial colonization and persistence of V. parahaemolyticus in the host. PMID:24455490

  13. Vibrio cholerae Exploits Sub-Lethal Concentrations of a Competitor-Produced Antibiotic to Avoid Toxic Interactions

    PubMed Central

    Graff, Jason R.; Forschner-Dancause, Stephanie R.; Menden-Deuer, Susanne; Long, Richard A.; Rowley, David C.

    2012-01-01

    Vibrio cholerae is a human pathogenic marine bacterium inhabiting coastal regions and is vectored into human food and water supplies via attachment to particles including detritus, phytoplankton, and zooplankton. Particle colonization by the pathogen is inhibited by an antagonistic interaction with the particle-associated Vibrionales bacterium SWAT3, a producer of the antibiotic andrimid. By analyzing the individual movement behaviors of V. cholerae exposed to a gradient of andrimid in a microfluidics device, we show that the pathogen has a concentration dependent avoidance response to sub-lethal concentrations of the pure antibiotic and to the metabolites produced by a growing colony of SWAT3-wild-type. This avoidance behavior includes a 25% increase in swimming speeds, 30% increase in run lengths, and a shift in the direction of the bacteria away from the andrimid source. Consequently, these behavioral shifts at low concentrations of andrimid would lead to higher diffusivity and result in the dispersion of bacteria away from the competitor and source of the antibiotic. Such alterations in motility were not elicited in response to a non-andrimid-producing SWAT3 mutant, suggesting andrimid may be a negative effector of chemotaxis for V. cholerae. The behavioral response of colonizing bacteria to sub-inhibitory concentrations of competitor-produced antibiotics is one mechanism that can influence microbial diversity and interspecific competition on particles, potentially affecting human health in coastal communities and element cycling in the ocean. PMID:23386845

  14. Molecular and phenotypic characterization of Vibrio navarrensis isolates associated with human illness.

    PubMed

    Gladney, Lori M; Tarr, Cheryl L

    2014-11-01

    We characterized 18 Vibrio isolates, including 15 recovered from human clinical specimens, and found that they clustered with two previously characterized Vibrio navarrensis isolates in a phylogenetic analysis. Four of the 18 strains may represent a new Vibrio species, distinct from V. navarrensis. The potential role of V. navarrensis in human disease needs further investigation. PMID:25187632

  15. Electrochemical genosensor assay using lyophilized gold nanoparticles/latex microsphere label for detection of Vibrio cholerae.

    PubMed

    Liew, Pei Sheng; Lertanantawong, Benchaporn; Lee, Su Yin; Manickam, Ravichandran; Lee, Yook Heng; Surareungchai, Werasak

    2015-07-01

    Vibrio cholerae is a Gram-negative bacterium that causes cholera, a diarrheal disease. Cholera is widespread in poor, under-developed or disaster-hit countries that have poor water sanitation. Hence, a rapid detection method for V. cholerae in the field under these resource-limited settings is required. In this paper, we describe the development of an electrochemical genosensor assay using lyophilized gold nanoparticles/latex microsphere (AuNPs-PSA) reporter label. The reporter label mixture was prepared by lyophilization of AuNPs-PSA-avidin conjugate with different types of stabilizers. The best stabilizer was 5% sorbitol, which was able to preserve the dried conjugate for up to 30 days. Three methods of DNA hybridization were compared and the one-step sandwich hybridization method was chosen as it was fastest and highly specific. The performance of the assay using the lyophilized reagents was comparable to the wet form for detection of 1aM to 1fM of linear target DNA. The assay was highly specific for V. cholerae, with a detection limit of 1fM of PCR products. The ability of the sensor is to detect LAMP products as low as 50ngµl(-1). The novel lyophilized AuNPs-PSA-avidin reporter label with electrochemical genosensor detection could facilitate the rapid on-site detection of V. cholerae. PMID:25882423

  16. Bile Acids and Bicarbonate Inversely Regulate Intracellular Cyclic di-GMP in Vibrio cholerae

    PubMed Central

    Koestler, Benjamin J.

    2014-01-01

    Vibrio cholerae is a Gram-negative bacterium that persists in aquatic reservoirs and causes the diarrheal disease cholera upon entry into a human host. V. cholerae employs the second messenger molecule 3?,5?-cyclic diguanylic acid (c-di-GMP) to transition between these two distinct lifestyles. c-di-GMP is synthesized by diguanylate cyclase (DGC) enzymes and hydrolyzed by phosphodiesterase (PDE) enzymes. Bacteria typically encode many different DGCs and PDEs within their genomes. Presumably, each enzyme senses and responds to cognate environmental cues by alteration of enzymatic activity. c-di-GMP represses the expression of virulence factors in V. cholerae, and it is predicted that the intracellular concentration of c-di-GMP is low during infection. Contrary to this model, we found that bile acids, a prevalent constituent of the human proximal small intestine, increase intracellular c-di-GMP in V. cholerae. We identified four c-di-GMP turnover enzymes that contribute to increased intracellular c-di-GMP in the presence of bile acids, and deletion of these enzymes eliminates the bile induction of c-di-GMP and biofilm formation. Furthermore, this bile-mediated increase in c-di-GMP is quenched by bicarbonate, the intestinal pH buffer secreted by intestinal epithelial cells. Our results lead us to propose that V. cholerae senses distinct microenvironments within the small intestine using bile and bicarbonate as chemical cues and responds by modulating the intracellular concentration of c-di-GMP. PMID:24799624

  17. Transcription termination within the iron transport-biosynthesis operon of Vibrio anguillarum requires an antisense RNA.

    PubMed

    Stork, Michiel; Di Lorenzo, Manuela; Welch, Timothy J; Crosa, Jorge H

    2007-05-01

    The iron transport-biosynthesis (ITB) operon in Vibrio anguillarum includes four genes for ferric siderophore transport, fatD, -C, -B, and -A, and two genes for siderophore biosynthesis, angR and angT. This cluster plays an important role in the virulence mechanisms of this bacterium. Despite being part of the same polycistronic mRNA, the relative levels of transcription for the fat portion and for the whole ITB message differ profoundly, the levels of the fat transcript being about 17-fold higher. Using S1 nuclease mapping, lacZ transcriptional fusions, and in vitro studies, we were able to show that the differential gene expression within the ITB operon is due to termination of transcription between the fatA and angR genes, although a few transcripts proceeded beyond the termination site to the end of this operon. This termination process requires a 427-nucleotide antisense RNA that spans the intergenic region and acts as a novel transcriptional terminator. PMID:17337574

  18. Insights into the environmental reservoir of pathogenic Vibrio parahaemolyticus using comparative genomics

    PubMed Central

    Hazen, Tracy H.; Lafon, Patricia C.; Garrett, Nancy M.; Lowe, Tiffany M.; Silberger, Daniel J.; Rowe, Lori A.; Frace, Michael; Parsons, Michele B.; Bopp, Cheryl A.; Rasko, David A.; Sobecky, Patricia A.

    2015-01-01

    Vibrio parahaemolyticus is an aquatic halophilic bacterium that occupies estuarine and coastal marine environments, and is a leading cause of seafood-borne food poisoning cases. To investigate the environmental reservoir and potential gene flow that occurs among V. parahaemolyticus isolates, the virulence-associated gene content and genome diversity of a collection of 133 V. parahaemolyticus isolates were analyzed. Phylogenetic analysis of housekeeping genes, and pulsed-field gel electrophoresis, demonstrated that there is genetic similarity among V. parahaemolyticus clinical and environmental isolates. Whole-genome sequencing and comparative analysis of six representative V. parahaemolyticus isolates was used to identify genes that are unique to the clinical and environmental isolates examined. Comparative genomics demonstrated an O3:K6 environmental isolate, AF91, which was cultured from sediment collected in Florida in 2006, has significant genomic similarity to the post-1995 O3:K6 isolates. However, AF91 lacks the majority of the virulence-associated genes and genomic islands associated with these highly virulent post-1995 O3:K6 genomes. These findings demonstrate that although they do not contain most of the known virulence-associated regions, some V. parahaemolyticus environmental isolates exhibit significant genetic similarity to clinical isolates. This highlights the dynamic nature of the V. parahaemolyticus genome allowing them to transition between aquatic and host-pathogen states.

  19. Increased Isolation Frequency of Toxigenic Vibrio cholerae O1 from Environmental Monitoring Sites in Haiti

    PubMed Central

    Alam, Meer T.; Weppelmann, Thomas A.; Longini, Ira; De Rochars, Valery Madsen Beau; Morris, John Glenn; Ali, Afsar

    2015-01-01

    Since the identification of the first cholera case in 2010, the disease has spread in epidemic form throughout the island nation of Haiti; as of 2014, about 700,000 cholera cases have been reported, with over 8,000 deaths. While case numbers have declined, the more fundamental question of whether the causative bacterium, Vibrio cholerae has established an environmental reservoir in the surface waters of Haiti remains to be elucidated. In a previous study conducted between April 2012 and March 2013, we reported the isolation of toxigenic V. cholerae O1 from surface waters in the Ouest Department. After a second year of surveillance (April 2013 to March 2014) using identical methodology, we observed a more than five-fold increase in the number of water samples containing culturable V. cholerae O1 compared to the previous year (1.7% vs 8.6%), with double the number of sites having at least one positive sample (58% vs 20%). Both seasonal water temperatures and precipitation were significantly related to the frequency of isolation. Our data suggest that toxigenic V. cholerae O1 are becoming more common in surface waters in Haiti; while the basis for this increase is uncertain, our findings raise concerns that environmental reservoirs are being established. PMID:25853552

  20. Identifying the cellular mechanisms of symbiont-induced epithelial morphogenesis in the squid-Vibrio association.

    PubMed

    Koropatnick, Tanya; Goodson, Michael S; Heath-Heckman, Elizabeth A C; McFall-Ngai, Margaret

    2014-02-01

    The symbiotic association between the Hawaiian bobtail squid Euprymna scolopes and the luminous marine bacterium Vibrio fischeri provides a unique opportunity to study epithelial morphogenesis. Shortly after hatching, the squid host harvests bacteria from the seawater using currents created by two elaborate fields of ciliated epithelia on the surface of the juvenile light organ. After light organ colonization, the symbiont population signals the gradual loss of the ciliated epithelia through apoptosis of the cells, which culminates in the complete regression of these tissues. Whereas aspects of this process have been studied at the morphological, biochemical, and molecular levels, no in-depth analysis of the cellular events has been reported. Here we describe the cellular structure of the epithelial field and present evidence that the symbiosis-induced regression occurs in two steps. Using confocal microscopic analyses, we observed an initial epithelial remodeling, which serves to disable the function of the harvesting apparatus, followed by a protracted regression involving actin rearrangements and epithelial cell extrusion. We identified a metal-dependent gelatinolytic activity in the symbiont-induced morphogenic epithelial fields, suggesting the involvement of Zn-dependent matrix metalloproteinase(s) (MMP) in light organ morphogenesis. These data show that the bacterial symbionts not only induce apoptosis of the field, but also change the form, function, and biochemistry of the cells as part of the morphogenic program. PMID:24648207

  1. Effects of electrolyzed oxidizing water treatment on reducing Vibrio parahaemolyticus and Vibrio vulnificus in raw oysters.

    PubMed

    Ren, Tingting; Su, Yi-Cheng

    2006-08-01

    Contamination of Vibrio parahaemolyticus and Vibrio vulnificus in oysters is a food safety concern. This study investigated effects of electrolyzed oxidizing (EO) water treatment on reducing V. parahaemolyticus and V. vulnificus in laboratory-contaminated oysters. EO water exhibited strong antibacterial activity against V. parahaemolyticus and V. vulnificus in pure cultures. Populations of V. parahaemolyticus (8.74 x 10(7) CFU/ml) and V. vulnificus (8.69 x 10(7) CFU/ml) decreased quickly in EO water containing 0.5% NaCl to nondetectable levels (> 6.6 log reductions) within 15 s. Freshly harvested Pacific oysters were inoculated with a five-strain cocktail of V. parahaemolyticus or V. vulnificus at levels of 10(4) and 10(6) most probable number (MPN)/g and treated with EO water (chlorine, 30 ppm; pH 2.82; oxidation-reduction potential, 1131 mV) containing 1% NaCl at room temperature. Reductions of V. parahaemolyticus and V. vulnificus in oysters were determined at 0 (before treatment), 2, 4, 6, and 8 h of treatment. Holding oysters inoculated with V. parahaemolyticus or V. vulnificus in the EO water containing 1% NaCl for 4 to 6 h resulted in significant (P < 0.05) reductions of V. parahaemolyticus and V. vulnificus by 1.13 and 1.05 log MPN/g, respectively. Extended exposure (> 12 h) of oysters in EO water containing high levels of chlorine (> 30 ppm) was found to be detrimental to oysters. EO water could be used as a postharvest treatment to reduce Vibrio contamination in oysters. However, treatment should be limited to 4 to 6 h to avoid death of oysters. Further studies are needed to determine effects of EO water treatment on sensory characteristics of oysters. PMID:16924906

  2. Isolation of Vibrio vulnificus from Seawater and Emerging Vibrio vulnificus Septicemia on Jeju Island

    PubMed Central

    Lee, Keun Hwa; Kim, Young Ree; Pang, Ig-Chan

    2014-01-01

    Vibrio vulnificus is an opportunistic human pathogen, transmitted from seawater, raw oyster, and shellfish and responsible for severe septicemia. We studied V. vulnificus from surface seawater around Jeju Island between 2010 and 2011. In 2010, V. vulnificus was isolated and V. vulnificus septicemia was reported. Surface seawater temperature is an important factor for growth of V. vulnificus, and here we showed that high surface seawater temperature may influence growth of V. vulnificus and occurrence of emerging V. vulnificus septicemia on Jeju Island. This is the first report of isolation of V. vulnificus and emerging V. vulnificus septicemia on Jeju Island. PMID:25024873

  3. New Vibrio species associated to molluscan microbiota: a review.

    PubMed

    Romalde, Jesús L; Dieguez, Ana L; Lasa, Aide; Balboa, Sabela

    2014-01-01

    The genus Vibrio consists of more than 100 species grouped in 14 clades that are widely distributed in aquatic environments such as estuarine, coastal waters, and sediments. A large number of species of this genus are associated with marine organisms like fish, molluscs and crustaceans, in commensal or pathogenic relations. In the last decade, more than 50 new species have been described in the genus Vibrio, due to the introduction of new molecular techniques in bacterial taxonomy, such as multilocus sequence analysis or fluorescent amplified fragment length polymorphism. On the other hand, the increasing number of environmental studies has contributed to improve the knowledge about the family Vibrionaceae and its phylogeny. Vibrio crassostreae, V. breoganii, V. celticus are some of the new Vibrio species described as forming part of the molluscan microbiota. Some of them have been associated with mortalities of different molluscan species, seriously affecting their culture and causing high losses in hatcheries as well as in natural beds. For other species, ecological importance has been demonstrated being highly abundant in different marine habitats and geographical regions. The present work provides an updated overview of the recently characterized Vibrio species isolated from molluscs. In addition, their pathogenic potential and/or environmental importance is discussed. PMID:24427157

  4. Ecological study of pathogenic vibrios in aquatic environments.

    PubMed

    Shinoda, Sumio; Furumai, Yuki; Katayama, Sei-Ichi; Mizuno, Tamaki; Miyoshi, Shin-Ichi

    2013-01-01

    An ecological study of pathogenic vibrios in aquatic environments of Okayama was carried out. The number of Vibrio parahaemolyticus detected in the sea area was comparatively smaler than that found in the survey of about two decades ago. Various reasons for the decrease in the case of food poisoning by V. parahaemolyticus have been suggested but the lower number of the vibrio in aquatic environments may be one explanation. Although the number of V. vulnificus was also not as large, most of the isolates possessed the pathogenic genes, vvp and vvh, suggesting the potential for fatal pathogenicity to patients having underlying diseases. As for V. cholerae, some non-O1/non-O139 serovar isolates were detected in a fresh water area, and many of them had hlyA, the gene for hemolysin which acts as a pathogenic factor in sporadic cases of diarrhea. Thus, the total number of pathogenic vibrios detected was not of concern. However, the marine products of these areas are shipped in wide area and are for general consumption. Therefore, it is necessary to continue to survey pathogenic vibrios in aquatic environments in order to ensure food hygiene. PMID:23538851

  5. New Vibrio species associated to molluscan microbiota: a review

    PubMed Central

    Romalde, Jesús L.; Dieguez, Ana L.; Lasa, Aide; Balboa, Sabela

    2014-01-01

    The genus Vibrio consists of more than 100 species grouped in 14 clades that are widely distributed in aquatic environments such as estuarine, coastal waters, and sediments. A large number of species of this genus are associated with marine organisms like fish, molluscs and crustaceans, in commensal or pathogenic relations. In the last decade, more than 50 new species have been described in the genus Vibrio, due to the introduction of new molecular techniques in bacterial taxonomy, such as multilocus sequence analysis or fluorescent amplified fragment length polymorphism. On the other hand, the increasing number of environmental studies has contributed to improve the knowledge about the family Vibrionaceae and its phylogeny. Vibrio crassostreae, V. breoganii, V. celticus are some of the new Vibrio species described as forming part of the molluscan microbiota. Some of them have been associated with mortalities of different molluscan species, seriously affecting their culture and causing high losses in hatcheries as well as in natural beds. For other species, ecological importance has been demonstrated being highly abundant in different marine habitats and geographical regions. The present work provides an updated overview of the recently characterized Vibrio species isolated from molluscs. In addition, their pathogenic potential and/or environmental importance is discussed. PMID:24427157

  6. Vibriophages and Their Interactions with the Fish Pathogen Vibrio anguillarum

    PubMed Central

    Tan, Demeng; Gram, Lone

    2014-01-01

    Vibrio anguillarum is an important pathogen in aquaculture, responsible for the disease vibriosis in many fish and invertebrate species. Disease control by antibiotics is a concern due to potential development and spread of antibiotic resistance. The use of bacteriophages to control the pathogen may offer a non-antibiotic-based approach to reduce vibriosis. A detailed understanding of the phage-host interaction is needed to evaluate the potential of phages to control the pathogen. In this study, we examined the diversity and interactions of 11 vibriophages, 24 V. anguillarum strains, and 13 Vibrio species strains. Together, the host ranges of the 11 phages covered all of the tested 37 Vibrio sp. host strains, which represented considerable temporal (20 years) and geographical (9 countries) differences in their origins of isolation. Thus, despite the occurrence of unique susceptibility patterns of the individual host isolates, key phenotypic properties related to phage susceptibility are distributed worldwide and maintained in the global Vibrio community for decades. The phage susceptibility pattern of the isolates did not show any relation to the physiological relationships obtained from Biolog GN2 profiles, demonstrating that similar phage susceptibility patterns occur across broad phylogenetic and physiological differences in Vibrio strains. Subsequent culture experiments with two phages and two V. anguillarum hosts demonstrated an initial strong lytic potential of the phages. However, rapid regrowth of both phage-resistant and phage-sensitive cells following the initial lysis suggested that several mechanisms of protection against phage infection had developed in the host populations. PMID:24610858

  7. Bacterium Can Alter Evolution Of Another Species

    NSDL National Science Digital Library

    Jonathan Sherwood

    This Daily University Science News article reviews scientific evidence that the parasitic bacterium Wolbachia can accelerate the natural evolution of wasps by altering the sperm of its male host, thus making them incompatible with non-infected females. The article discusses this evidence as well as introduces a current debate about Wolbachia's role in host speciation.

  8. New spiral bacterium in gastric mucosa

    Microsoft Academic Search

    C A McNulty; J C Dent; A Curry; J S Uff; G A Ford; M W Gear; S P Wilkinson

    1989-01-01

    A new spiral bacterium, distinct from Campylobacter pylori, was found in the gastric mucosa of six patients with gastrointestinal symptoms. All patients had chronic active type B gastritis and four had oesophagitis. Culture and microscopy for C pylori infection was negative. These unculturable spiral organisms were probably an incidental finding in patients presenting for upper gastrointestinal endoscopy, but it is

  9. Vibrio fischeri flavohemoglobin protects against nitric oxide during initiation of the squid-Vibrio symbiosis

    PubMed Central

    Wang, Yanling; Dunn, Anne K.; Wilneff, Jacqueline; McFall-Ngai, Margaret J.; Spiro, Stephen; Ruby, Edward G.

    2010-01-01

    Summary Nitric oxide (NO) is implicated in a wide range of biological processes, including innate immunity against pathogens, signal transduction, and protection against oxidative stress. However, its possible roles in beneficial host-microbe associations are less well recognized. During the early stages of the squid-vibrio symbiosis, the bacterial symbiont Vibrio fischeri encounters host-derived NO, which has been hypothesized to serve as specificity determinant. We demonstrate here that the flavohemoglobin, Hmp, of V. fischeri protects against NO, both in culture and during colonization of the squid host. Transcriptional analyses indicate that hmp expression is highly responsive to NO, principally through the repressor, NsrR. Hmp protects V. fischeri from NO inhibition of aerobic respiration, and removes NO under both oxic and anoxic conditions. A ?hmp mutant of V. fischeri initiates squid colonization less effectively than wild type, but is rescued by the presence of an NO synthase inhibitor. The hmp promoter is activated during the initial stage of colonization, during which the ?hmp strain fails to form normal-sized aggregates of colonizing cells. Taken together, these results suggest that the sensing of host-derived NO by NsrR, and the subsequent removal of NO by Hmp, influence aggregate size and, thereby, V. fischeri colonization efficiency. PMID:20815823

  10. Enterotoxin production by Vibrio cholerae and Vibrio mimicus grown in continuous culture with microbial cell recycle.

    PubMed Central

    Spira, W M; Fedorka-Cray, P J

    1983-01-01

    We have examined the effect of complete cell recycle on the production of cholera toxin (CT) by Vibrio cholerae and CT-like toxin by Vibrio mimicus in continuous culture fermentations. Complete cell recycle was obtained by filtering culture fluids through Amicon hollow fibers with an exclusion limit of 100,000 daltons (H1P100-20) and returning the concentrated cell slurry to the fermentor. A single 1-liter laboratory fermentor system modified with this recycle loop was capable of producing over 20 liters of cell-free culture filtrate per day. Toxin production in this system was compared with yields obtained in traditional continuous cultures and in shake flask cultures. Yields of CT from V. cholerae 569B in the recycle fermentor were highest at the highest dilution rate employed (1.0 vol/vol per h). The use of complete cell recycle dramatically increased yields over those obtained in continuous culture and equaled those obtained in shake flasks. The concentration of CT in the filtrate was slightly less than half of that measured in culture fluids sampled at the same time. Similarly, V. mimicus 61892 grown in the presence of 50 micrograms of lincomycin per ml produced 280 ng of CT per ml in the recycle fermentor, compared with 210 ng/ml in shake flasks under optimal conditions. The sterile filtrate from this fermentation contained 110 ng/ml. PMID:6357081

  11. Aquatic ecology of the oyster pathogens Vibrio splendidus and Vibrio aestuarianus.

    PubMed

    Vezzulli, Luigi; Pezzati, Elisabetta; Stauder, Monica; Stagnaro, Laura; Venier, Paola; Pruzzo, Carla

    2015-04-01

    The ecology of the oyster pathogens Vibrio splendidus and Vibrio aestuarianus in the brackish aquatic environment was extensively investigated in this study. By conducting laboratory experiments under natural setting conditions, it was shown that V.?splendidus?LGP32 strain generally exhibits longer persistence in both seawater and sediment than V.?aestuarianus 01/32 strain. Both strains maintained viability and culturability for longer times in the sediment, suggesting that this compartment may represent a suitable niche for their persistence in the environment. In addition, both strains attached to chitin particles and copepods, the efficiency of attachment being higher in V.?splendidus than in V.?aestuarianus. Similarly, LGP32 strain showed a greater capability to form biofilm on poly-vinyl chloride (PVC) surfaces than 01/32 strain. LGP32 and 01/32 strains were also capable of entering a viable but non-culturable state after extended incubation at 5°C, a condition commonly found during cold season in the aquatic brackish environment. These results are consistent with field data collected during a 2-year sampling campaign in the northern Adriatic Sea and provide background information on the mechanisms promoting V.?splendidus and V.?aestuarianus persistence in coastal water, thus contributing to a better understanding of the epidemiology of the associated diseases. PMID:24725454

  12. Mechanism of Vibrio cholerae autoinducer-1 biosynthesis.

    PubMed

    Wei, Yunzhou; Perez, Lark J; Ng, Wai-Leung; Semmelhack, Martin F; Bassler, Bonnie L

    2011-04-15

    Vibrio cholerae, the causative agent of the disease cholera, uses a cell to cell communication process called quorum sensing to control biofilm formation and virulence factor production. The major V. cholerae quorum-sensing signal CAI-1 has been identified as (S)-3-hydroxytridecan-4-one, and the CqsA protein is required for CAI-1 production. However, the biosynthetic route to CAI-1 remains unclear. Here we report that (S)-adenosylmethionine (SAM) is one of the two biosynthetic substrates for CqsA. CqsA couples SAM and decanoyl-coenzyme A to produce a previously unknown but potent quorum-sensing molecule, 3-aminotridec-2-en-4-one (Ea-CAI-1). The CqsA mechanism is unique; it combines two enzymatic transformations, a ?,?-elimination of SAM and an acyltransferase reaction into a single PLP-dependent catalytic process. Ea-CAI-1 is subsequently converted to CAI-1, presumably through the intermediate tridecane-3,4-dione (DK-CAI-1). We propose that the Ea-CAI-1 to DK-CAI-1 conversion occurs spontaneously, and we identify the enzyme responsible for the subsequent step: conversion of DK-CAI-1 into CAI-1. SAM is the substrate for the synthesis of at least three different classes of quorum-sensing signal molecules, indicating that bacteria have evolved a strategy to leverage an abundant substrate for multiple signaling purposes. PMID:21197957

  13. Dynamics in genome evolution of Vibrio cholerae.

    PubMed

    Banerjee, Rachana; Das, Bhabatosh; Balakrish Nair, G; Basak, Surajit

    2014-04-01

    Vibrio cholerae, the etiological agent of the acute secretary diarrheal disease cholera, is still a major public health concern in developing countries. In former centuries cholera was a permanent threat even to the highly developed populations of Europe, North America, and the northern part of Asia. Extensive studies on the cholera bug over more than a century have made significant advances in our understanding of the disease and ways of treating patients. V. cholerae has more than 200 serogroups, but only few serogroups have caused disease on a worldwide scale. Until the present, the evolutionary relationship of these pandemic causing serogroups was not clear. In the last decades, we have witnessed a shift involving genetically and phenotypically varied pandemic clones of V. cholerae in Asia and Africa. The exponential knowledge on the genome of several representatives V. cholerae strains has been used to identify and analyze the key determinants for rapid evolution of cholera pathogen. Recent comparative genomic studies have identified the presence of various integrative mobile genetic elements (IMGEs) in V. cholerae genome, which can be used as a marker of differentiation of all seventh pandemic clones with very similar core genome. This review attempts to bring together some of the important researches in recent times that have contributed towards understanding the genetics, epidemiology and evolution of toxigenic V. cholerae strains. PMID:24462909

  14. Comparative genomics of clinical and environmental Vibrio mimicus

    PubMed Central

    Hasan, Nur A.; Grim, Christopher J.; Haley, Bradd J.; Chun, Jongsik; Alam, Munirul; Taviani, Elisa; Hoq, Mozammel; Munk, A. Christine; Saunders, Elizabeth; Brettin, Thomas S.; Bruce, David C.; Challacombe, Jean F.; Detter, J. Chris; Han, Cliff S.; Xie, Gary; Nair, G. Balakrish; Huq, Anwar; Colwell, Rita R.

    2010-01-01

    Whether Vibrio mimicus is a variant of Vibrio cholerae or a separate species has been the subject of taxonomic controversy. A genomic analysis was undertaken to resolve the issue. The genomes of V. mimicus MB451, a clinical isolate, and VM223, an environmental isolate, comprise ca. 4,347,971 and 4,313,453 bp and encode 3,802 and 3,290 ORFs, respectively. As in other vibrios, chromosome I (C-I) predominantly contains genes necessary for growth and viability, whereas chromosome II (C-II) bears genes for adaptation to environmental change. C-I harbors many virulence genes, including some not previously reported in V. mimicus, such as mannose-sensitive hemagglutinin (MSHA), and enterotoxigenic hemolysin (HlyA); C-II encodes a variant of Vibrio pathogenicity island 2 (VPI-2), and Vibrio seventh pandemic island II (VSP-II) cluster of genes. Extensive genomic rearrangement in C-II indicates it is a hot spot for evolution and genesis of speciation for the genus Vibrio. The number of virulence regions discovered in this study (VSP-II, MSHA, HlyA, type IV pilin, PilE, and integron integrase, IntI4) with no notable difference in potential virulence genes between clinical and environmental strains suggests these genes also may play a role in the environment and that pathogenic strains may arise in the environment. Significant genome synteny with prototypic pre-seventh pandemic strains of V. cholerae was observed, and the results of phylogenetic analysis support the hypothesis that, in the course of evolution, V. mimicus and V. cholerae diverged from a common ancestor with a prototypic sixth pandemic genomic backbone. PMID:21078967

  15. Current perspectives on the epidemiology and pathogenesis of clinically significant Vibrio spp.

    PubMed Central

    Janda, J M; Powers, C; Bryant, R G; Abbott, S L

    1988-01-01

    Recent taxonomic advances have now implicated several different Vibrio species as human pathogens. While the most common clinical presentation of Vibrio infection continues to be gastroenteritis, an increasing number of extraintestinal infections are being reported, particularly in immunocompromised individuals. Detection of Vibrio infections requires a good clinical history and the use of appropriate isolation and identification procedures by the laboratory to confirm illnesses attributed to Vibrio species. Except for Vibrio cholerae O1 and Vibrio parahaemolyticus, there is little direct evidence linking the production of a myriad of cell-associated or extracellular factors produced by each species with human disease and pathogenesis. Many questions regarding pathogenic Vibrio species remain unanswered, including their frequency and distribution in environmental specimens (water, shellfish), infective doses, virulence potential of individual isolates, and markers associated with such strains. Images PMID:3058295

  16. Long-term effects of ocean warming on vibrios

    NASA Astrophysics Data System (ADS)

    Pruzzo, C.; Pezzati, E.; Brettar, I.; Reid, P. C.; Colwell, R.; Höfle, M. G.; vezzulli, L.

    2012-12-01

    Vibrios are a major source of human disease, play an important role in the ecology and health of marine animals and are regarded as an abundant fraction of culturable bacteria of the ocean. There has been a considerable global effort to reduce the risk of Vibrio infections and yet in most countries both human and non-human illnesses associated with these bacteria are increasing. The cause of this increase is not known, but since vibrios are strongly thermodependant there is good reason to believe that global warming may have contributed. To investigate this possibility we examined historical samples from the Continuous Plankton Recorder (CPR) archive using advanced molecular analysis and pyrosequencing. For the first time we were able to recover environmental DNA from CPR samples that had been stored for up to ~50 years in a formalin-fixed format, which is suitable for molecular analyses of the associated prokaryotic community. To overcome the problem of DNA degradation due to the sample age and storage in formalin we develop an unbiased index of abundance for Vibrio quantification in CPR samples termed a 'relative Vibrio Abundance Index' (VAI). VAI is defined as the ratio of Vibrio spp. cells to total bacterial cells assessed by Real-Time PCR using genus-specific and universal primers, respectively, producing small amplicons of similar size (~100bp). We assessed VAI index on 55 samples (each representing 10 nautical miles tow equal to 3 m3 of filtered sewater) collected in August by the CPR survey in the North Sea from off the Rhine and Humber estuaries between 1961 to 2005 showing that the genus Vibrio has increased in prevalence in the last 44 years and that this increase is correlated significantly, during the same period, with warming sea surface temperature. In addition, by applying deep sequencing analysis of a subset of these samples we provide evidence that bacteria belonging to the genus Vibrio, including the human pathogen V. cholerae, not only increased in occurrence over the last half century in the southern North Sea, but also prevailed within the particle associated bacterial community of coastal marine waters. These findings provide support for the view that global warming may have a strong impact on the composition of marine bacterial communities with important implications for human and animal health into the future.

  17. Characterization of tryptophanase from Vibrio cholerae.

    PubMed

    Nuidate, Taiyeebah; Tansila, Natta; Chomchuen, Piraporn; Phattaranit, Phattiphong; Eangchuan, Supachok; Vuddhakul, Varaporn

    2015-01-01

    Tryptophanase (Trpase) is a pyridoxal phosphate (PLP)-dependent enzyme responsible for the production of indole, an important intra- and interspecies signaling molecule in bacteria. In this study, the tnaA gene of Vibrio cholerae coding for VcTrpase was cloned into the pET-20b(+) vector and expressed in Escherichia coli BL21(DE3) tn5:tnaA. Using Ni(2+)-nitrilotriacetic acid (NTA) chromatography, VcTrpase was purified, and it possessed a molecular mass of ?49 kDa with specific absorption peaks at 330 and 435 nm and a specific activity of 3 U/mg protein. The VcTrpase had an 80 % homology to the Trpase of Haemophilus influenzae and E. coli, but only around 50 % identity to the Trpase of Proteus vulgaris and Porphyromonas gingivalis. The optimum conditions for the enzyme were at pH 9.0 and 45 °C. Recombinant VcTrpase exhibited analogous kinetic reactivity to the EcTrpase with K m and k cat values of 0.612?×?10(-3) M and 5.252 s(-1), respectively. The enzyme catalyzed S-methyl-L-cysteine and S-benzyl-L-cysteine degradation, but not L-phenylalanine and L-serine. Using a site-directed mutagenesis technique, eight residues (Thr52, Tyr74, Arg103, Asp137, Arg230, Lys269, Lys270, and His463) were conserved for maintaining enzyme catalysis. All amino acid substitutions at these sites either eliminated or remarkably diminished Trpase activity. These sites are thus potential targets for the design of drugs to control the V. cholerae Trpase and to further investigate its functions. PMID:25253268

  18. Predictability of Vibrio cholerae in Chesapeake Bay

    PubMed Central

    Louis, Valérie R.; Russek-Cohen, Estelle; Choopun, Nipa; Rivera, Irma N. G.; Gangle, Brian; Jiang, Sunny C.; Rubin, Andrea; Patz, Jonathan A.; Huq, Anwar; Colwell, Rita R.

    2003-01-01

    Vibrio cholerae is autochthonous to natural waters and can pose a health risk when it is consumed via untreated water or contaminated shellfish. The correlation between the occurrence of V. cholerae in Chesapeake Bay and environmental factors was investigated over a 3-year period. Water and plankton samples were collected monthly from five shore sampling sites in northern Chesapeake Bay (January 1998 to February 2000) and from research cruise stations on a north-south transect (summers of 1999 and 2000). Enrichment was used to detect culturable V. cholerae, and 21.1% (n = 427) of the samples were positive. As determined by serology tests, the isolates, did not belong to serogroup O1 or O139 associated with cholera epidemics. A direct fluorescent-antibody assay was used to detect V. cholerae O1, and 23.8% (n = 412) of the samples were positive. V. cholerae was more frequently detected during the warmer months and in northern Chesapeake Bay, where the salinity is lower. Statistical models successfully predicted the presence of V. cholerae as a function of water temperature and salinity. Temperatures above 19°C and salinities between 2 and 14 ppt yielded at least a fourfold increase in the number of detectable V. cholerae. The results suggest that salinity variation in Chesapeake Bay or other parameters associated with Susquehanna River inflow contribute to the variability in the occurrence of V. cholerae and that salinity is a useful indicator. Under scenarios of global climate change, increased climate variability, accompanied by higher stream flow rates and warmer temperatures, could favor conditions that increase the occurrence of V. cholerae in Chesapeake Bay. PMID:12732548

  19. Comparison of the use of mussels and semipermeable membrane devices for monitoring and assessment of accumulation of mutagenic pollutants in marine environment in combination with a novel microbiological mutagenicity assay.

    PubMed

    Che?, Ewa; Podgórska, Beata; Wegrzyn, Grzegorz

    2008-05-01

    A novel microbiological mutagenicity assay, based on bioluminescence of a marine bacterium Vibrio harveyi mutant strain, potentially suitable for monitoring and assessment of mutagenic pollution of marine environment, has been described recently. Here, we tested the use of this assay, in combination with either mussels (Mytilus sp.) or semipermeable membrane devices (SPMDs), in assessment of accumulation of mutagens in marine water (samples of Baltic Sea water were tested). Either similar results were obtained in both systems or higher signals in the SPMD-based system were detected, depending on the tested water samples. We conclude that the use of both mussels and SPMDs in combination with the V. harveyi bioluminescence mutagenicity assay is a method suitable for monitoring and assessment of accumulation of mutagenic pollutants in marine environment, but in some cases the SPMD-based system may provide a more sensitive test. PMID:17562194

  20. Swimming efficiency of bacterium Escherichia coli

    PubMed Central

    Chattopadhyay, Suddhashil; Moldovan, Radu; Yeung, Chuck; Wu, X. L.

    2006-01-01

    We use measurements of swimming bacteria in an optical trap to determine fundamental properties of bacterial propulsion. In particular, we directly measure the force required to hold the bacterium in the optical trap and determine the propulsion matrix, which relates the translational and angular velocity of the flagellum to the torques and forces propelling the bacterium. From the propulsion matrix, dynamical properties such as torques, swimming speed, and power can be obtained by measuring the angular velocity of the motor. We find significant heterogeneities among different individuals even though all bacteria started from a single colony. The propulsive efficiency, defined as the ratio of the propulsive power output to the rotary power input provided by the motors, is found to be ?2%, which is consistent with the efficiency predicted theoretically for a rigid helical coil. PMID:16954194

  1. Characterization of Vibrio metschnikovii and Vibrio gazogenes by DNA-DNA hybridization and phenotype.

    PubMed Central

    Farmer, J J; Hickman-Brenner, F W; Fanning, G R; Gordon, C M; Brenner, D J

    1988-01-01

    Vibrio metschnikovii and Vibrio gazogenes are two new Vibrio species that have been little studied. Thirteen strains of V. metschnikovii were highly related to the type strain, NCTC 8443, by DNA-DNA hybridization. Relatedness values were 83 to 90% at 60 degrees C and 75 to 84% at the more stringent 75 degrees C. Divergence values ranged from 0.7 to 1.9. Strains of V. metschnikovii were oxidase negative and did not reduce nitrate to nitrite. The other phenotypic characteristics agreed with published data. Twenty-three strains of V. gazogenes were isolated from salt marshes and marshy areas on the coast of North and South Carolina. A new medium, marine agar supplemented with an additional 2.5% agar, reduced the problem of swarming by marine Vibrio species and enhanced the isolation of V. gazogenes and other organisms. By DNA-DNA hybridization, 22 of 23 strains were 76% or more related to the type strain of V. gazogenes, ATCC 29988. However, four DNA hybridization subgroups were defined on the basis of divergence values and/or phenotype. Strains of DNA group 1 were more highly related to each other, and this group contained the type strain and six other strains. Strains of DNA group 2 were more highly related to each other, and this group contained reference strain ATCC 43942 and 14 other strains. Strains of DNA group 1 did not ferment melibiose or D-sorbitol (one strain was sorbitol positive), but strains of DNA group 2 fermented both sugars. A revised phenotypic description of V. gazogenes based on 24 strains was written on the basis of reactions (within 2 days of incubation) at 25 degrees C in media supplemented with Na+, K+, and Mg2+. Positive results (100% positive unless indicated) included motility; gas production during fermentation (96% at 2 days, 100% at 3 to 7 days); growth in nutrient broth with the addition of 1% NaCl (88%), 2% NaCl, 3.5% NaCl, 6% NaCl, 8% NaCl, and 10% NaCl (92%); dry red or orange colonies on marine agar; and fermentation of L-arabinose, cellobiose, D-galactose (88%), D-glucose, lactose (88%), maltose, D-mannitol (96%), D-mannose, salicin, sucrose, trehalose, and D-xylose. Negative results included oxidase; nitrate reduction to nitrite (4% positive); indole production; lysine decarboxylase; ornithine decarboxylase; arginine dihydrolase; swarming; growth on TCBS agar; growth in nutrient broth with 0% NaCl, 0.1% NaCl, 0.2% NaCl, 0.3% NaCl, and 0.4% NaCl (8% positive); and fermentation of adonitol, D-arabitol, dulcitol, erythritol, D-galacturonate, i-inositol, alpha-methyl-D-glucoside, raffinose, and L-rhamnose. Variable results were found for the Voges-Proskauer reaction (62% positive), growth in nutrient broth plus 0.5% NaCl (29%) and 12% NaCL (42%), and fermentation of melibiose (71%) and D-sorbitol (71%). PMID:3182990

  2. Characterization of a novel extremely alkalophilic bacterium

    NASA Technical Reports Server (NTRS)

    Souza, K. A.; Deal, P. H.

    1977-01-01

    A new alkalophilic bacterium, isolated from a natural spring of high pH is characterized. It is a Gram-positive, non-sporulating, motile rod requiring aerobic and alkaline conditions for growth. The characteristics of this organism resemble those of the coryneform group of bacteria; however, there are no accepted genera within this group with which this organism can be closely matched. Therefore, a new genus may be warranted.

  3. Paradigms: examples from the bacterium Xylella fastidiosa.

    PubMed

    Purcell, Alexander

    2013-01-01

    The history of advances in research on Xylella fastidiosa provides excellent examples of how paradigms both advance and limit our scientific understanding of plant pathogens and the plant diseases they cause. I describe this from a personal perspective, having been directly involved with many persons who made paradigm-changing discoveries, beginning with the discovery that a bacterium, not a virus, causes Pierce's disease of grape and other plant diseases in numerous plant species, including important crop and forest species. PMID:23682911

  4. Proteolysis of Virulence Regulator ToxR Is Associated with Entry of Vibrio cholerae into a Dormant State

    PubMed Central

    Almagro-Moreno, Salvador; Kim, Tae K.; Skorupski, Karen; Taylor, Ronald K.

    2015-01-01

    Vibrio cholerae O1 is a natural inhabitant of aquatic environments and causes the diarrheal disease, cholera. Two of its primary virulence regulators, TcpP and ToxR, are localized in the inner membrane. TcpP is encoded on the Vibrio Pathogenicity Island (VPI), a horizontally acquired mobile genetic element, and functions primarily in virulence gene regulation. TcpP has been shown to undergo regulated intramembrane proteolysis (RIP) in response to environmental conditions that are unfavorable for virulence gene expression. ToxR is encoded in the ancestral genome and is present in non-pathogenic strains of V. cholerae, indicating it has roles outside of the human host. In this study, we show that ToxR undergoes RIP in V. cholerae in response to nutrient limitation at alkaline pH, a condition that occurs during the stationary phase of growth. This process involves the site-2 protease RseP (YaeL), and is dependent upon the RpoE-mediated periplasmic stress response, as deletion mutants for the genes encoding these two proteins cannot proteolyze ToxR under nutrient limitation at alkaline pH. We determined that the loss of ToxR, genetically or by proteolysis, is associated with entry of V. cholerae into a dormant state in which the bacterium is normally found in the aquatic environment called viable but nonculturable (VBNC). Strains that can proteolyze ToxR, or do not encode it, lose culturability, experience a change in morphology associated with cells in VBNC, yet remain viable under nutrient limitation at alkaline pH. On the other hand, mutant strains that cannot proteolyze ToxR remain culturable and maintain the morphology of cells in an active state of growth. Overall, our findings provide a link between the proteolysis of a virulence regulator and the entry of a pathogen into an environmentally persistent state. PMID:25849031

  5. Establishment of an animalbacterial association: Recruiting symbiotic vibrios from

    E-print Network

    McFall-Ngai, Margaret

    are specifically detected and me- tabolized by symbiotically competent bacteria in the family RhizobiaceaeEstablishment of an animal­bacterial association: Recruiting symbiotic vibrios from the environment no secretions unless Gram-negative bacteria, either living or dead, were reintroduced. The viscous material

  6. NATURAL TRANSFORMATION OF A MARINE VIBRIO SPECIES BY PLASMID DNA

    EPA Science Inventory

    A series of thirty marine and estuarine bacterial isolates was examined for the ability to naturally transform with plasmid DNA. One isolate from Tampa Bay, Florida, identified as Vibrio parahaemolyticus, successfully incorporated and maintained the broad host range plasmid pKT23...

  7. Vibrio cholerae Requires rpoS for Efficient Intestinal Colonization

    Microsoft Academic Search

    D. SCOTT MERRELL; ANNA D. TISCHLER; SANG HO LEE; ANDREW CAMILLI

    2000-01-01

    Vibrio cholerae is a facultative intestinal pathogen that lives in aquatic environments, often in association with planktonic species. In the suckling mouse, oral inoculation with V. cholerae leads to intestinal colonization and symptoms of diarrheal disease. Results reported here indicate a role for the alternative sigma factor, RpoS, in intestinal colonization in this model of cholera. We constructed within rpoS

  8. Improved Method for Detection of Vibrio parahaemolyticus in Seafood

    Microsoft Academic Search

    YUKIKO HARA-KUDO; TOKUHIRO NISHINA; HIROSHI NAKAGAWA; HIROTAKA KONUMA; JUNKO HASEGAWA; SUSUMU KUMAGAI

    2001-01-01

    We have developed a new, effective procedure for detecting Vibrio parahaemolyticus in seafoods using enrichment and plating onto a chromogenic agar medium. Samples were cultured in salt Trypticase soy broth, which is a nonselective medium, and then a portion of the culture was cultured with salt polymyxin broth, which is a selective medium for V. parahaemolyticus. This two-step enrichment was

  9. Vibrio Trends in the Ecology of the Venice Lagoon

    PubMed Central

    Rahman, Mohammad Shamsur; Cardazzo, Barbara; Facco, Pierantonio; Bordin, Paola; Mioni, Renzo; Novelli, Enrico; Fasolato, Luca

    2014-01-01

    Vibrio is a very diverse genus that is responsible for different human and animal diseases. The accurate identification of Vibrio at the species level is important to assess the risks related to public health and diseases caused by aquatic organisms. The ecology of Vibrio spp., together with their genetic background, represents an important key for species discrimination and evolution. Thus, analyses of population structure and ecology association are necessary for reliable characterization of bacteria and to investigate whether bacterial species are going through adaptation processes. In this study, a population of Vibrionaceae was isolated from shellfish of the Venice lagoon and analyzed in depth to study its structure and distribution in the environment. A multilocus sequence analysis (MLSA) was developed on the basis of four housekeeping genes. Both molecular and biochemical approaches were used for species characterization, and the results were compared to assess the consistency of the two methods. In addition, strain ecology and the association between genetic information and environment were investigated through statistical models. The phylogenetic and population analyses achieved good species clustering, while biochemical identification was demonstrated to be imprecise. In addition, this study provided a fine-scale overview of the distribution of Vibrio spp. in the Venice lagoon, and the results highlighted a preferential association of the species toward specific ecological variables. These findings support the use of MLSA for taxonomic studies and demonstrate the need to consider environmental information to obtain broader and more accurate bacterial characterization. PMID:24487545

  10. Natural modulators of Vibrios in seawater and shellfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Naturally occurring marine bacteria, Vibrio parahaemolyticus and V. vulnificus, are major threats to the safety of molluscan shellfish in the US and elsewhere. Illnesses range from mild gastrointestinal upset to septicemia and death. In studies on the uptake and persistence of V. parahaemolyticus ...

  11. Induction of the lateral flagellar system of Vibrio shilonii is an early event after inhibition of the sodium ion flux in the polar flagellum.

    PubMed

    González, Yael; Camarena, Laura; Dreyfus, Georges

    2015-03-01

    In this study, we show the induction of lateral flagella by the action of the sodium channel blocker phenamil, in the marine bacterium Vibrio shilonii, a coral pathogen that causes bleaching. We analyzed the growth and morphology of cells treated with phenamil. A time course analysis showed that after 30 min of exposure to the sodium channel blocker, lateral flagella were present and could be detected by electron microscopy. Detection of the mRNA of the master regulator (lafK) and lateral flagellin (lafA) by RT-PCR confirmed the expression of lateral flagellar genes. We show the simultaneous isolation of polar and, for the first time, lateral flagellar hook-basal bodies. This allowed us to compare the dimensions and morphological characteristics of the 2 structures. PMID:25639364

  12. A Quorum Sensing-Disrupting Brominated Thiophenone with a Promising Therapeutic Potential to Treat Luminescent Vibriosis

    PubMed Central

    Defoirdt, Tom; Benneche, Tore; Brackman, Gilles; Coenye, Tom; Sorgeloos, Patrick; Scheie, Anne Aamdal

    2012-01-01

    Vibrio harveyi is amongst the most important bacterial pathogens in aquaculture. Novel methods to control this pathogen are needed since many strains have acquired resistance to antibiotics. We previously showed that quorum sensing-disrupting furanones are able to protect brine shrimp larvae against vibriosis. However, a major problem of these compounds is that they are toxic toward higher organisms and therefore, they are not safe to be used in aquaculture. The synthesis of brominated thiophenones, sulphur analogues of the quorum sensing-disrupting furanones, has recently been reported. In the present study, we report that these compounds block quorum sensing in V. harveyi at concentrations in the low micromolar range. Bioluminescence experiments with V. harveyi quorum sensing mutants and a fluorescence anisotropy assay indicated that the compounds disrupt quorum sensing in this bacterium by decreasing the ability of the quorum sensing master regulator LuxR to bind to its target promoter DNA. In vivo challenge tests with gnotobiotic brine shrimp larvae showed that thiophenone compound TF310, (Z)-4-((5-(bromomethylene)-2-oxo-2,5-dihydrothiophen-3-yl)methoxy)-4-oxobutanoic acid, completely protected the larvae from V. harveyi BB120 when dosed to the culture water at 2.5 µM or more, whereas severe toxicity was only observed at 250 µM. This makes TF310 showing the highest therapeutic index of all quorum sensing-disrupting compounds tested thus far in our brine shrimp model system. PMID:22848604

  13. Acyl-acyl carrier protein as a source of fatty acids for bacterial bioluminescence

    SciTech Connect

    Byers, D.M.; Meighen, E.A.

    1985-09-01

    Pulse-chase experiments with (/sup 3/H)tetradecanoic acid and ATP showed that the bioluminescence-related 32-kDa acyltransferase from Vibrio harveyi can specifically catalyze the deacylation of a /sup 3/H-labeled 18-kDa protein observed in extracts of this bacterium. The 18-kDa protein has been partially purified and its physical and chemical properties strongly indicate that it is fatty acyl-acyl carrier protein (acyl-ACP). Both this V. harveyi (/sup 3/H)acylprotein and (/sup 3/H)palmitoyl-ACP from Escherichia coli were substrates in vitro for either the V. harveyi 32-kDa acyltransferase or the analogous enzyme (34K) from Photobacterium phosphoreum. TLC analysis indicated that the hexane-soluble product of the reaction is fatty acid. No significant cleavage of either E. coli or V. harveyi tetradecanoyl-ACP was observed in extracts of these bacteria unless the 32-kDa or 34K acyltransferase was present. Since these enzymes are believed to be responsible for the supply of fatty acids for reduction to form the aldehyde substrate of luciferase, the above results suggest that long-chain acyl-ACP is the source of fatty acids for bioluminescence.

  14. Vibrio Infections and Surveillance in Maryland, 2002–2008

    PubMed Central

    Feldman, Katherine A.; Palmer, Amanda; Butler, Erin; Blythe, David; Mitchell, Clifford S.

    2013-01-01

    Objective Vibrio is a naturally occurring waterborne pathogen with potential occupational, recreational, and commercial impacts. During the last 15 years in the U.S. and in Maryland, the incidence of vibriosis has increased. Due to the increase in cases in Maryland, warming water temperatures, and public concern about human health effects resulting from exposure to the Chesapeake Bay, we reviewed cases of vibriosis and evaluated the Vibrio surveillance system in Maryland for timeliness and data quality, attributes necessary for successful outbreak investigation and illness prevention. Methods The evaluation included (1) informal qualitative surveys of state and local personnel who report and manage Vibrio cases and (2) a review of Vibrio surveillance data from 2002 through 2008 for data quality and timeliness of the system. Results From 2002 to 2008, 188 laboratory-confirmed cases of vibriosis were reported in Maryland with an annual average of 27 cases. The species of Vibrio that were most frequently responsible for infection, regardless of clinical presentation, were V. parahaemolyticus (43.6%), V. vulnificus (23.9%), V. alginolyticus (9.6%), and non-toxigenic V. cholerae (9.0%). The case fatality rate fluctuated during the study period, but the number of cases increased. Conclusions The surveillance system in Maryland is flexible and captures cases of vibriosis where specimens were collected for testing; however, the system may not adequately capture mild, self-limiting infections. Better integration of data collection for clinical, laboratory, and environmental information and improved completion of variables for shellfish harvest or water exposure locations could improve the system. Quarterly meetings comprising surveillance, public health laboratory, and food-control personnel could direct and ensure the success of improvement efforts. PMID:24179265

  15. Design of Vibrio 16S rRNA gene specific primers and their application in the analysis of seawater Vibrio community

    NASA Astrophysics Data System (ADS)

    Yong, Liu; Guanpin, Yang; Hualei, Wang; Jixiang, Chen; Xianming, Shi; Guiwei, Zou; Qiwei, Wei; Xiuqin, Sun

    2006-04-01

    The pathogenic species of genus Vibrio cause vibriosis, one of the most prevalent diseases of maricultured animals and seafood consumers. Monitoring their kinetics in the chain of seafood production, processing and consumption is of great importance for food and mariculture safety. In order to enrich Vibrio-representing 16S ribosomal RNA gene (rDNA) fragments and identify these bacteria further real-timely and synchronously among bacterial flora in the chain, a pair of primers that selectively amplify Vibrio 16S rDNA fragments were designed with their specificities and coverage testified in the analysis of seawater Vibrio community. The specificities and coverage of two primers, VF169 and VR744, were determined theoretically among bacterial 16S rDNAs available in GenBank by using BLAST program and practically by amplifying, Vibrio 16S rDNA fragments from seawater DNA. More than 88.3% of sequences in GenBank, which showed identical matches with VR744, belong to Vibrio genus. A total of 33 clones were randomly selected and sequenced. All of the sequences showed their highest similarities to and clustered around those of diverse known Vibrio species. The primers designed are capable of retrieving a wide range of Vibrio 16S rDNA fragments specifically among bacterial flora in seawater, the most important natural environment of seafood cultivation.

  16. The catecholamine stress hormones norepinephrine and dopamine increase the virulence of pathogenic Vibrio anguillarum and Vibrio campbellii.

    PubMed

    Pande, Gde Sasmita J; Suong, Nguyen Thao; Bossier, Peter; Defoirdt, Tom

    2014-12-01

    Obtaining a better understanding of mechanisms involved in bacterial infections is of paramount importance for the development of novel agents to control disease caused by (antibiotic resistant) pathogens in aquaculture. In this study, we investigated the impact of catecholamine stress hormones on growth and virulence factor production of pathogenic vibrios (i.e. two Vibrio campbellii strains and two Vibrio anguillarum strains). Both norepinephrine and dopamine (at 100 ?M) significantly induced growth in media containing serum. The compounds also increased swimming motility of the tested strains, whereas they had no effect on caseinase, chitinase, and hemolysin activities. Further, antagonists for eukaryotic catecholamine receptors were able to neutralize some of the effects of the catecholamines. Indeed, the dopaminergic receptor antagonist chlorpromazine neutralized the effect of dopamine, and the ?-adrenergic receptor antagonists phentolamine and phenoxybenzamine neutralized the effect of norepinephrine, whereas the ?-adrenergic receptor antagonist propranolol had limited to no effect. Finally, pretreatment of pathogenic V. campbellii with catecholamines significantly increased its virulence toward giant freshwater prawn larvae. However, the impact of catecholamine receptor antagonists on in vivo virulence was less clear-cut when compared to the in vitro experiments. In summary, our results show that—similar to enteric pathogens—catecholamines also increase the virulence of vibrios that are pathogenic to aquatic organisms by increasing motility and growth in media containing serum. PMID:25264299

  17. Household Transmission of Vibrio cholerae in Bangladesh

    PubMed Central

    Sugimoto, Jonathan D.; Koepke, Amanda A.; Kenah, Eben E.; Halloran, M. Elizabeth; Chowdhury, Fahima; Khan, Ashraful I.; LaRocque, Regina C.; Yang, Yang; Ryan, Edward T.; Qadri, Firdausi; Calderwood, Stephen B.; Harris, Jason B.; Longini, Ira M.

    2014-01-01

    Background Vibrio cholerae infections cluster in households. This study's objective was to quantify the relative contribution of direct, within-household exposure (for example, via contamination of household food, water, or surfaces) to endemic cholera transmission. Quantifying the relative contribution of direct exposure is important for planning effective prevention and control measures. Methodology/Principal Findings Symptom histories and multiple blood and fecal specimens were prospectively collected from household members of hospital-ascertained cholera cases in Bangladesh from 2001–2006. We estimated the probabilities of cholera transmission through 1) direct exposure within the household and 2) contact with community-based sources of infection. The natural history of cholera infection and covariate effects on transmission were considered. Significant direct transmission (p-value<0.0001) occurred among 1414 members of 364 households. Fecal shedding of O1 El Tor Ogawa was associated with a 4.9% (95% confidence interval: 0.9%–22.8%) risk of infection among household contacts through direct exposure during an 11-day infectious period (mean length). The estimated 11-day risk of O1 El Tor Ogawa infection through exposure to community-based sources was 2.5% (0.8%–8.0%). The corresponding estimated risks for O1 El Tor Inaba and O139 infection were 3.7% (0.7%–16.6%) and 8.2% (2.1%–27.1%) through direct exposure, and 3.4% (1.7%–6.7%) and 2.0% (0.5%–7.3%) through community-based exposure. Children under 5 years-old were at elevated risk of infection. Limitations of the study may have led to an underestimation of the true risk of cholera infection. For instance, available covariate data may have incompletely characterized levels of pre-existing immunity to cholera infection. Transmission via direct exposure occurring outside of the household was not considered. Conclusions Direct exposure contributes substantially to endemic transmission of symptomatic cholera in an urban setting. We provide the first estimate of the transmissibility of endemic cholera within prospectively-followed members of households. The role of direct transmission must be considered when planning cholera control activities. PMID:25411971

  18. RNA thermometer controls temperature-dependent virulence factor expression in Vibrio cholerae

    PubMed Central

    Weber, Gregor G.; Kortmann, Jens; Narberhaus, Franz; Klose, Karl E.

    2014-01-01

    Vibrio cholerae is the bacterium that causes the diarrheal disease cholera. The bacteria experience a temperature shift as V. cholerae transition from contaminated water at lower temperatures into the 37 °C human intestine. Within the intestine, V. cholerae express cholera toxin (CT) and toxin-coregulated pilus (TCP), two main virulence factors required for disease. CT and TCP expression is controlled by the transcriptional activator protein ToxT. We identified an RNA thermometer motif in the 5? UTR of toxT, with a fourU anti-Shine-Dalgarno (SD) element that base pairs with the SD sequence to regulate ribosome access to the mRNA. RNA probing experiments demonstrated that the fourU element allowed access to the SD sequence at 37 °C but not at 20 °C. Moreover, mutations within the fourU element (U5C, U7C) that strengthened base-pairing between the anti-SD and SD sequences prevented access to the SD sequence even at 37 °C. Translation of ToxT-FLAG from the native toxT UTR was enhanced at 37 °C, compared with 25 °C in both Escherichia coli and V. cholerae. In contrast, the U5C, U7C UTR prevented translation of ToxT-FLAG even at 37 °C. V. cholerae mutants containing the U5C, U7C UTR variant were unable to colonize the infant mouse small intestine. Our results reveal a previously unknown regulatory mechanism consisting of an RNA thermometer that controls temperature-dependent translation of toxT, facilitating V. cholerae virulence at a relevant environmental condition found in the human intestine. PMID:25228776

  19. A Metalloprotease Secreted by the Type II Secretion System Links Vibrio cholerae with Collagen.

    PubMed

    Park, Bo R; Zielke, Ryszard A; Wierzbicki, Igor H; Mitchell, Kristie C; Withey, Jeffrey H; Sikora, Aleksandra E

    2015-03-15

    Vibrio cholerae is autochthonous to various aquatic niches and is the etiological agent of the life-threatening diarrheal disease cholera. The persistence of V. cholerae in natural habitats is a crucial factor in the epidemiology of cholera. In contrast to the well-studied V. cholerae-chitin connection, scarce information is available about the factors employed by the bacteria for the interaction with collagens. Collagens might serve as biologically relevant substrates, because they are the most abundant protein constituents of metazoan tissues and V. cholerae has been identified in association with invertebrate and vertebrate marine animals, as well as in a benthic zone of the ocean where organic matter, including collagens, accumulates. Here, we describe the characterization of the V. cholerae putative collagenase, VchC, encoded by open reading frame VC1650 and belonging to the subfamily M9A peptidases. Our studies demonstrate that VchC is an extracellular collagenase degrading native type I collagen of fish and mammalian origin. Alteration of the predicted catalytic residues coordinating zinc ions completely abolished the protein enzymatic activity but did not affect the translocation of the protease by the type II secretion pathway into the extracellular milieu. We also show that the protease undergoes a maturation process with the aid of a secreted factor(s). Finally, we propose that V. cholerae is a collagenovorous bacterium, as it is able to utilize collagen as a sole nutrient source. This study initiates new lines of investigations aiming to uncover the structural and functional components of the V. cholerae collagen utilization program. PMID:25561716

  20. H-NOX-mediated nitric oxide sensing modulates symbiotic colonization by Vibrio fischeri.

    PubMed

    Wang, Yanling; Dufour, Yann S; Carlson, Hans K; Donohue, Timothy J; Marletta, Michael A; Ruby, Edward G

    2010-05-01

    The bioluminescent bacterium Vibrio fischeri initiates a specific, persistent symbiosis in the light organ of the squid Euprymna scolopes. During the early stages of colonization, V. fischeri is exposed to host-derived nitric oxide (NO). Although NO can be both an antimicrobial component of innate immunity and a key signaling molecule in eukaryotes, potential roles in beneficial host-microbe associations have not been described. V. fischeri hnoX encodes a heme NO/oxygen-binding (H-NOX) protein, a member of a family of bacterial NO- and/or O(2)-binding proteins of unknown function. We hypothesized that H-NOX acts as a NO sensor that is involved in regulating symbiosis-related genes early in colonization. Whole-genome expression studies identified 20 genes that were repressed in an NO- and H-NOX-dependent fashion. Ten of these, including hemin-utilization genes, have a promoter with a putative ferric-uptake regulator (Fur) binding site. As predicted, in the presence of NO, wild-type V. fischeri grew more slowly on hemin than a hnoX deletion mutant. Host-colonization studies showed that the hnoX mutant was also 10-fold more efficient in initially colonizing the squid host than the wild type; similarly, in mixed inoculations, it outcompeted the wild-type strain by an average of 16-fold after 24 h. However, the presence of excess hemin or iron reversed this dominance. The advantage of the mutant in colonizing the iron-limited light-organ tissues is caused, at least in part, by its greater ability to acquire host-derived hemin. Our data suggest that V. fischeri normally senses a host-generated NO signal through H-NOX(Vf) and modulates the expression of its iron uptake capacity during the early stages of the light-organ symbiosis. PMID:20404170

  1. Population Structure of Clinical Vibrio parahaemolyticus from 17 Coastal Countries, Determined through Multilocus Sequence Analysis

    PubMed Central

    Lu, Jun; Wang, Guangzhou; Zhou, Lin; Min, Lingfeng; Han, Chongxu

    2014-01-01

    Vibrio parahaemolyticus is a leading cause of food-borne gastroenteritis worldwide. Although this bacterium has been the subject of much research, the population structure of clinical strains from worldwide collections remains largely undescribed, and the recorded outbreaks of V. parahaemolyticus gastroenteritis highlight the need for the subtyping of this species. We present a broad phylogenetic analysis of 490 clinical V. parahaemolyticus isolates from 17 coastal countries through multilocus sequence analysis (MLST). The 490 tested isolates fell into 161 sequence types (STs). The eBURST algorithm revealed that the 161 clinically relevant STs belonged to 8 clonal complexes, 11 doublets, and 94 singletons, showing a high level of genetic diversity. CC3 was found to be a global epidemic clone of V. parahaemolyticus, and ST-3 was the only ST with an international distribution. recA was observed to be evolving more rapidly, exhibiting the highest degree of nucleotide diversity (0.028) and the largest number of polymorphic nucleotide sites (177). We also found that the high variability of recA was an important cause of differences between the results of the eBURST and ME tree analyses, suggesting that recA has a much greater influence on the apparent evolutionary classification of V. parahaemolyticus based on the current MLST scheme. In conclusion, it is evident that a high degree of genetic diversity within the V. parahaemolyticus population and multiple sequence types are contributing to the burden of disease around the world. MLST, with a fully extractable database, is a powerful system for analysis of the clonal relationships of strains at a global scale. With the addition of more strains, the pubMLST database will provide more detailed and accurate information, which will be conducive to our future research on the population structure of V. parahaemolyticus. PMID:25225911

  2. RNA thermometer controls temperature-dependent virulence factor expression in Vibrio cholerae.

    PubMed

    Weber, Gregor G; Kortmann, Jens; Narberhaus, Franz; Klose, Karl E

    2014-09-30

    Vibrio cholerae is the bacterium that causes the diarrheal disease cholera. The bacteria experience a temperature shift as V. cholerae transition from contaminated water at lower temperatures into the 37 °C human intestine. Within the intestine, V. cholerae express cholera toxin (CT) and toxin-coregulated pilus (TCP), two main virulence factors required for disease. CT and TCP expression is controlled by the transcriptional activator protein ToxT. We identified an RNA thermometer motif in the 5' UTR of toxT, with a fourU anti-Shine-Dalgarno (SD) element that base pairs with the SD sequence to regulate ribosome access to the mRNA. RNA probing experiments demonstrated that the fourU element allowed access to the SD sequence at 37 °C but not at 20 °C. Moreover, mutations within the fourU element (U5C, U7C) that strengthened base-pairing between the anti-SD and SD sequences prevented access to the SD sequence even at 37 °C. Translation of ToxT-FLAG from the native toxT UTR was enhanced at 37 °C, compared with 25 °C in both Escherichia coli and V. cholerae. In contrast, the U5C, U7C UTR prevented translation of ToxT-FLAG even at 37 °C. V. cholerae mutants containing the U5C, U7C UTR variant were unable to colonize the infant mouse small intestine. Our results reveal a previously unknown regulatory mechanism consisting of an RNA thermometer that controls temperature-dependent translation of toxT, facilitating V. cholerae virulence at a relevant environmental condition found in the human intestine. PMID:25228776

  3. Vibrio cholerae Infection of Drosophila melanogaster Mimics the Human Disease Cholera

    PubMed Central

    Blow, Nathan S; Salomon, Robert N; Garrity, Kerry; Reveillaud, Isabelle; Kopin, Alan; Jackson, F. Rob; Watnick, Paula I

    2005-01-01

    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 the susceptibility of the fruit fly, Drosophila melanogaster, to oral V. cholerae infection through a process that exhibits many of the hallmarks of human disease: (i) death of the fly is dependent on the presence of cholera toxin and is preceded by rapid weight loss; (ii) flies harboring mutant alleles of either adenylyl cyclase, Gs?, or the Gardos K+ channel homolog SK are resistant to V. cholerae infection; and (iii) ingestion of a K+ channel blocker along with V. cholerae protects wild-type flies against death. In mammals, ingestion of as little as 25 ?g of cholera toxin results in massive diarrhea. In contrast, we found that ingestion of cholera toxin was not lethal to the fly. However, when cholera toxin was co-administered with a pathogenic strain of V. cholerae carrying a chromosomal deletion of the genes encoding cholera toxin, death of the fly ensued. These findings suggest that additional virulence factors are required for intoxication of the fly that may not be essential for intoxication of mammals. Furthermore, we demonstrate for the first time the mechanism of action of cholera toxin in a whole organism and the utility of D. melanogaster as an accurate, inexpensive model for elucidation of host susceptibility to cholera. PMID:16201020

  4. Molecular characterization of vulnibactin biosynthesis in Vibrio vulnificus indicates the existence of an alternative siderophore.

    PubMed

    Tan, Wenzhi; Verma, Vivek; Jeong, Kwangjoon; Kim, Soo Young; Jung, Che-Hun; Lee, Shee Eun; Rhee, Joon Haeng

    2014-01-01

    Vibrio vulnificus is a halophilic estuarine bacterium that causes fatal septicemia and necrotizing wound infections in humans. Virulent V. vulnificus isolates produce a catechol siderophore called vulnibactin, made up of one residue of 2, 3-dihydroxybenzoic acid (2, 3-DHBA) and two residues of salicylic acid (SA). Vulnibactin biosynthetic genes (VV2_0828 to VV2_0844) are clustered at one locus of chromosome 2, expression of which is significantly up-regulated in vivo. In the present study, we decipher the biosynthetic network of vulnibactin, focusing specifically on genes around SA and 2, 3-DHBA biosynthetic steps. Deletion mutant of isochorismate pyruvate lyase (VV2_0839) or 2, 3-dihydroxybenzoate-2, 3-dehydrogenase (VV2_0834) showed retarded growth under iron-limited conditions though the latter showed more significant growth defect than the former, suggesting a dominant role of 2, 3-DHBA in the vulnibactin biosynthesis. A double deletion mutant of VV2_0839 and VV2_0834 manifested additional growth defect under iron limitation. Though the growth defect of respective single deletion mutants could be restored by exogenous SA or 2, 3-DHBA, only 2, 3-DHBA could rescue the double mutant when supplied alone. However, double mutant could be rescued with SA only when hydrogen peroxide was supplied exogenously, suggesting a chemical conversion of SA to 2, 3-DHBA. Assembly of two SA and one 2, 3-DHBA into vulnibactin was mediated by two AMP ligase genes (VV2_0836 and VV2_0840). VV2_0836 deletion mutant showed more significant growth defect under iron limitation, suggesting its dominant function. In conclusion, using molecular genetic analytical tools, we confirm that vulnibactin is assembled of both 2, 3-DHBA and SA. However, conversion of SA to 2, 3-DHBA in presence of hydrogen peroxide and growth profile of AMP ligase mutants suggest a plausible existence of yet unidentified alternative siderophore that may be composed solely of 2, 3-DHBA. PMID:24478763

  5. Activation of Cholera Toxin Production by Anaerobic Respiration of Trimethylamine N-oxide in Vibrio cholerae*

    PubMed Central

    Lee, Kang-Mu; Park, Yongjin; Bari, Wasimul; Yoon, Mi Young; Go, Junhyeok; Kim, Sang Cheol; Lee, Hyung-il; Yoon, Sang Sun

    2012-01-01

    Vibrio cholerae is a Gram-negative bacterium that causes cholera. Although the pathogenesis caused by this deadly pathogen takes place in the intestine, commonly thought to be anaerobic, anaerobiosis-induced virulence regulations are not fully elucidated. Anerobic growth of the V. cholerae strain, N16961, was promoted when trimethylamine N-oxide (TMAO) was used as an alternative electron acceptor. Strikingly, cholera toxin (CT) production was markedly induced during anaerobic TMAO respiration. N16961 mutants unable to metabolize TMAO were incapable of producing CT, suggesting a mechanistic link between anaerobic TMAO respiration and CT production. TMAO reductase is transported to the periplasm via the twin arginine transport (TAT) system. A similar defect in both anaerobic TMAO respiration and CT production was also observed in a N16961 TAT mutant. In contrast, the abilities to grow on TMAO and to produce CT were not affected in a mutant of the general secretion pathway. This suggests that V. cholerae may utilize the TAT system to secrete CT during TMAO respiration. During anaerobic growth with TMAO, N16961 cells exhibit green fluorescence when stained with 2?,7?-dichlorofluorescein diacetate, a specific dye for reactive oxygen species (ROS). Furthermore, CT production was decreased in the presence of an ROS scavenger suggesting a positive role of ROS in regulating CT production. When TMAO was co-administered to infant mice infected with N16961, the mice exhibited more severe pathogenic symptoms. Together, our results reveal a novel anaerobic growth condition that stimulates V. cholerae to produce its major virulence factor. PMID:23019319

  6. Genetic Diversity of Clinical and Environmental Vibrio parahaemolyticus Strains from the Pacific Northwest

    PubMed Central

    Hamel, Owen S.; Stojanovski, Asta; Liermann, Martin

    2012-01-01

    Since 1997, cases of Vibrio parahaemolyticus-related gastroenteritis from the consumption of raw oysters harvested in Washington State have been higher than historical levels. These cases have shown little or no correlation with concentrations of potentially pathogenic V. parahaemolyticus (positive for the thermostable direct hemolysin gene, tdh) in oysters, although significant concentrations of tdh+ V. parahaemolyticus strains were isolated from shellfish-growing areas in the Pacific Northwest (PNW). We compared clinical and environmental strains isolated from the PNW to those from other geographic regions within the United States and Asia for the presence of virulence-associated genes, including the thermostable direct hemolysin (tdh), the thermostable-related hemolysin (trh), urease (ureR), the pandemic group specific markers orf8 and toxRS, and genes encoding both type 3 secretion systems (T3SS1 and T3SS2). The majority of clinical strains from the PNW were positive for tdh, trh, and ureR genes, while a significant proportion of environmental isolates were tdh+ but trh negative. Hierarchical clustering grouped the majority of these clinical isolates into a cluster distinct from that including the pandemic strain RIMD2210633, clinical isolates from other geographical regions, and tdh+, trh-negative environmental isolates from the PNW. We detected T3SS2-related genes (T3SS2?) in environmental strains that were tdh and trh negative. The presence of significant concentrations of tdh+, trh-negative environmental strains in the PNW that have not been responsible for illness and T3SS2? in tdh- and trh-negative strains emphasizes the diversity in this species and the need to identify additional virulence markers for this bacterium to improve risk assessment tools for the detection of this pathogen. PMID:23042162

  7. Selectivity of Vibrio cholerae H-NOX for Gaseous Ligands Follows “Sliding Scale Rule” Hypothesis

    PubMed Central

    Wu, Gang; Liu, Wen; Berka, Vladimir; Tsai, Ah-lim

    2014-01-01

    Vc H-NOX (or VCA0720) is an H-NOX (heme-nitric oxide and oxygen binding) protein from facultative aerobic bacterium Vibrio cholerae. It shares significant sequence homology with soluble guanylyl cyclase (sGC), a NO sensor protein commonly found in animals. Similar to sGC, Vc H-NOX binds strongly to NO and CO with affinities of 0.27 nM and 0.77 ?M, respectively, but weakly to O2. When positioned in “sliding scale” plot {Tsai, A.-L. et. al. (2012) Biochemistry, 51, pp172-86}, the line connecting logKD(NO) and logKD(CO) of Vc H-NOX is almost superimposable with that of Ns H-NOX. Therefore, the measured affinities and kinetic parameters of gaseous ligands to Vc H-NOX provide more evidence to validate the “sliding scale rule” hypothesis. Like sGC, Vc H-NOX binds NO in multiple steps, forming first a 6-coordinate heme-NO complex with a rate of 1.1 × 109 M?1s?1, and then converts to a 5c heme-NO complex at a rate also dependent on [NO]. Although the formation of oxyferrous Vc H-NOX is not detectable under normal atmospheric oxygen level, ferrous Vc H-NOX is oxidized to ferric form at a rate of 0.06 s?1 when mixed with O2. Ferric Vc H-NOX exists as a mixture of high- and low-spin states and is influenced by binding to different ligands. Characterization of both ferric and ferrous Vc H-NOX and their complexes with various ligands lay the foundation for understanding the possible dual roles in gas and redox sensing of Vc H-NOX. PMID:24351060

  8. PVv3, a New Shuttle Vector for Gene Expression in Vibrio vulnificus

    PubMed Central

    Klevanskaa, Karina; Bier, Nadja; Stingl, Kerstin; Strauch, Eckhard

    2014-01-01

    An efficient electroporation procedure for Vibrio vulnificus was designed using the new cloning vector pVv3 (3,107 bp). Transformation efficiencies up to 2 × 106 transformants per ?g DNA were achieved. The vector stably replicated in both V. vulnificus and Escherichia coli and was also successfully introduced into Vibrio parahaemolyticus and Vibrio cholerae. To demonstrate the suitability of the vector for molecular cloning, the green fluorescent protein (GFP) gene and the vvhBA hemolysin operon were inserted into the vector and functionally expressed in Vibrio and E. coli. PMID:24362421

  9. PVv3, a new shuttle vector for gene expression in Vibrio vulnificus.

    PubMed

    Klevanskaa, Karina; Bier, Nadja; Stingl, Kerstin; Strauch, Eckhard; Hertwig, Stefan

    2014-02-01

    An efficient electroporation procedure for Vibrio vulnificus was designed using the new cloning vector pVv3 (3,107 bp). Transformation efficiencies up to 2 × 10(6) transformants per ?g DNA were achieved. The vector stably replicated in both V. vulnificus and Escherichia coli and was also successfully introduced into Vibrio parahaemolyticus and Vibrio cholerae. To demonstrate the suitability of the vector for molecular cloning, the green fluorescent protein (GFP) gene and the vvhBA hemolysin operon were inserted into the vector and functionally expressed in Vibrio and E. coli. PMID:24362421

  10. VibrioBase: A Model for Next-Generation Genome and Annotation Database Development

    PubMed Central

    Choo, Siew Woh; Tan, Tze King; Mutha, Naresh V. R.; Wong, Guat Jah

    2014-01-01

    To facilitate the ongoing research of Vibrio spp., a dedicated platform for the Vibrio research community is needed to host the fast-growing amount of genomic data and facilitate the analysis of these data. We present VibrioBase, a useful resource platform, providing all basic features of a sequence database with the addition of unique analysis tools which could be valuable for the Vibrio research community. VibrioBase currently houses a total of 252 Vibrio genomes developed in a user-friendly manner and useful to enable the analysis of these genomic data, particularly in the field of comparative genomics. Besides general data browsing features, VibrioBase offers analysis tools such as BLAST interfaces and JBrowse genome browser. Other important features of this platform include our newly developed in-house tools, the pairwise genome comparison (PGC) tool, and pathogenomics profiling tool (PathoProT). The PGC tool is useful in the identification and comparative analysis of two genomes, whereas PathoProT is designed for comparative pathogenomics analysis of Vibrio strains. Both of these tools will enable researchers with little experience in bioinformatics to get meaningful information from Vibrio genomes with ease. We have tested the validity and suitability of these tools and features for use in the next-generation database development. PMID:25243218

  11. Detection and identification of Vibrio species using whole-cell protein pattern analysis.

    PubMed

    Lee, Chae-Yoon; Hong, Yeun; Ryu, Jio; Kim, Young-Rok; Oh, Sang-Suk; Lee, Soon-Ho; Hwang, In-Gyun; Kim, Hae-Yeong

    2012-08-01

    Outbreaks of foodborne diseases associated with Vibrio species such as V. parahaemolyticus, V. vulnificus, and V. cholerae frequently occur in countries having a dietary habit of raw seafood consumption. For rapid identification of different Vibrio species involved in foodborne diseases, whole-cell protein pattern analysis for 13 type strains of 12 Vibrio species was performed using SDS-PAGE analysis. Pathogenic Vibrio species such as V. parahaemolyticus, V. vulnificus, V. cholerae, V. alginolyticus, V. fluvialis, and V. mimicus were included in the 12 Vibrio species used in this study. Each of the 12 Vibrio species showed clearly specific band patterns of its own. Two different strains of V. parahaemolyticus showed two different SDS-PAGE wholecell protein patterns, giving the possibility of categorizing isolated strains in the same V. parahaemolyticus species into two subgroups. The 36 Vibrio isolates collected from sushi restaurants in Busan were all identified as V. parahaemolyticus by comparing their protein patterns with those of Vibrio type strains. The identified isolates were categorized into two different subgroups of V. parahaemolyticus. The whole-cell protein pattern analysis by SDS-PAGE can be used as a specific, rapid, and simple identification method for Vibrio spp. involved in foodborne diseases at the subspecies level. PMID:22713987

  12. Population Structure of Clinical and Environmental Vibrio parahaemolyticus from the Pacific Northwest Coast of the United States

    PubMed Central

    Turner, Jeffrey W.; Paranjpye, Rohinee N.; Landis, Eric D.; Biryukov, Stanley V.; González-Escalona, Narjol; Nilsson, William B.; Strom, Mark S.

    2013-01-01

    Vibrio parahaemolyticus is a common marine bacterium and a leading cause of seafood-borne bacterial gastroenteritis worldwide. Although this bacterium has been the subject of much research, the population structure of cold-water populations remains largely undescribed. We present a broad phylogenetic analysis of clinical and environmental V. parahaemolyticus originating largely from the Pacific Northwest coast of the United States. Repetitive extragenic palindromic PCR (REP-PCR) separated 167 isolates into 39 groups and subsequent multilocus sequence typing (MLST) separated a subset of 77 isolates into 24 sequence types. The Pacific Northwest population exhibited a semi-clonal structure attributed to an environmental clade (ST3, N?=?17 isolates) clonally related to the pandemic O3:K6 complex and a clinical clade (ST36, N?=?20 isolates) genetically related to a regionally endemic O4:K12 complex. Further, the identification of at least five additional clinical sequence types (i.e., ST43, 50, 65, 135 and 417) demonstrates that V. parahaemolyticus gastroenteritis in the Pacific Northwest is polyphyletic in nature. Recombination was evident as a significant source of genetic diversity and in particular, the recA and dtdS alleles showed strong support for frequent recombination. Although pandemic-related illnesses were not documented during the study, the environmental occurrence of the pandemic clone may present a significant threat to human health and warrants continued monitoring. It is evident that V. parahaemolyticus population structure in the Pacific Northwest is semi-clonal and it would appear that multiple sequence types are contributing to the burden of disease in this region. PMID:23409028

  13. Genome Sequencing of 15 Clinical Vibrio Isolates, Including 13 Non-O1/Non-O139 Serogroup Strains

    PubMed Central

    Johnson, Shannon L.; Verratti, Kathleen; Luu, Truong; Khiani, Amy; Awosika, Joy; Mokashi, Vishwesh P.; Chain, Patrick S. G.; Sozhamannan, Shanmuga

    2014-01-01

    We present draft genome sequences of 15 clinical Vibrio isolates of various serogroups. These are valuable data for use in studying Vibrio cholerae genetic diversity, epidemic potential, and strain attribution. PMID:25212618

  14. Meddling Vibrio cholerae Murmurs: A Neoteric Advancement in Cholera Research.

    PubMed

    Hema, M; Balasubramanian, Srikkanth; Princy, S Adline

    2015-06-01

    Cholera, a known diarrheal disease is associated with various risk factors like hypovolemic shock, rice watery stools, and death in developing countries. The overuse of antibiotics to treat cholera imposed a selective pressure for the emergence and spread of multi-drug resistant Vibrio cholerae strains. The failure of conventional antimicrobial therapy urged the researchers to find an alternative therapy that could meddle the cholera murmurs (Quorum Sensing). It seems to effectively overcome the conventional cholera therapies in parallel to decrease the morbidity and mortality rate in the developing countries. The paramount objective of this review essentially focuses on the different Quorum Sensing (QS) regulatory switches governing virulence and pathogenicity of Vibrio cholerae. This review also provides an insight into the plausible QS targets that could be exploited to bring about a breakthrough to the prevailing cholera therapy. PMID:25805898

  15. Transcriptional patterns in both host and bacterium underlie a daily rhythm of anatomical and metabolic change in a beneficial symbiosis

    PubMed Central

    Wier, Andrew M.; Nyholm, Spencer V.; Mandel, Mark J.; Massengo-Tiassé, R. Prisca; Schaefer, Amy L.; Koroleva, Irina; Splinter-BonDurant, Sandra; Brown, Bartley; Manzella, Liliana; Snir, Einat; Almabrazi, Hakeem; Scheetz, Todd E.; de Fatima Bonaldo, Maria; Casavant, Thomas L.; Soares, M. Bento; Cronan, John E.; Reed, Jennifer L.; Ruby, Edward G.; McFall-Ngai, Margaret J.

    2010-01-01

    Mechanisms for controlling symbiont populations are critical for maintaining the associations that exist between a host and its microbial partners. We describe here the transcriptional, metabolic, and ultrastructural characteristics of a diel rhythm that occurs in the symbiosis between the squid Euprymna scolopes and the luminous bacterium Vibrio fischeri. The rhythm is driven by the host’s expulsion from its light-emitting organ of most of the symbiont population each day at dawn. The transcriptomes of both the host epithelium that supports the symbionts and the symbiont population itself were characterized and compared at four times over this daily cycle. The greatest fluctuation in gene expression of both partners occurred as the day began. Most notable was an up-regulation in the host of >50 cytoskeleton-related genes just before dawn and their subsequent down-regulation within 6 h. Examination of the epithelium by TEM revealed a corresponding restructuring, characterized by effacement and blebbing of its apical surface. After the dawn expulsion, the epithelium reestablished its polarity, and the residual symbionts began growing, repopulating the light organ. Analysis of the symbiont transcriptome suggested that the bacteria respond to the effacement by up-regulating genes associated with anaerobic respiration of glycerol; supporting this finding, lipid analysis of the symbionts’ membranes indicated a direct incorporation of host-derived fatty acids. After 12 h, the metabolic signature of the symbiont population shifted to one characteristic of chitin fermentation, which continued until the following dawn. Thus, the persistent maintenance of the squid–vibrio symbiosis is tied to a dynamic diel rhythm that involves both partners. PMID:20133870

  16. Transcriptional patterns in both host and bacterium underlie a daily rhythm of anatomical and metabolic change in a beneficial symbiosis.

    PubMed

    Wier, Andrew M; Nyholm, Spencer V; Mandel, Mark J; Massengo-Tiassé, R Prisca; Schaefer, Amy L; Koroleva, Irina; Splinter-Bondurant, Sandra; Brown, Bartley; Manzella, Liliana; Snir, Einat; Almabrazi, Hakeem; Scheetz, Todd E; Bonaldo, Maria de Fatima; Casavant, Thomas L; Soares, M Bento; Cronan, John E; Reed, Jennifer L; Ruby, Edward G; McFall-Ngai, Margaret J

    2010-02-01

    Mechanisms for controlling symbiont populations are critical for maintaining the associations that exist between a host and its microbial partners. We describe here the transcriptional, metabolic, and ultrastructural characteristics of a diel rhythm that occurs in the symbiosis between the squid Euprymna scolopes and the luminous bacterium Vibrio fischeri. The rhythm is driven by the host's expulsion from its light-emitting organ of most of the symbiont population each day at dawn. The transcriptomes of both the host epithelium that supports the symbionts and the symbiont population itself were characterized and compared at four times over this daily cycle. The greatest fluctuation in gene expression of both partners occurred as the day began. Most notable was an up-regulation in the host of >50 cytoskeleton-related genes just before dawn and their subsequent down-regulation within 6 h. Examination of the epithelium by TEM revealed a corresponding restructuring, characterized by effacement and blebbing of its apical surface. After the dawn expulsion, the epithelium reestablished its polarity, and the residual symbionts began growing, repopulating the light organ. Analysis of the symbiont transcriptome suggested that the bacteria respond to the effacement by up-regulating genes associated with anaerobic respiration of glycerol; supporting this finding, lipid analysis of the symbionts' membranes indicated a direct incorporation of host-derived fatty acids. After 12 h, the metabolic signature of the symbiont population shifted to one characteristic of chitin fermentation, which continued until the following dawn. Thus, the persistent maintenance of the squid-vibrio symbiosis is tied to a dynamic diel rhythm that involves both partners. PMID:20133870

  17. Vibrio species associated with mortality of sharks held in captivity

    Microsoft Academic Search

    D. J. Grimes; J. Stemmler; H. Hada; E. B. May; D. Maneval; F. M. Hetrick; R. T. Jones; M. Stoskopf; R. R. Colwell

    1984-01-01

    Two urease-positiveVibrio spp. were isolated from a brown shark (Carcharhinus plumbeus) that died in captivity at a national aquarium. Morphological, biochemical, and molecular genetic studies revealed one of the isolates to beV. damsela; the other isolate was unique and has been classified asV. carchariae sp. nov. BothV. damsela andV. carchariae were found to be virulent for spiny dogfish (Squalus acanthias),

  18. Vibrio parahaemolyticus gastroenteritis outbreaks aboard two cruise ships.

    PubMed

    Lawrence, D N; Blake, P A; Yashuk, J C; Wells, J G; Creech, W B; Hughes, J H

    1979-01-01

    Outbreaks of Vibrio parahaemolyticus gastrointestinal illness occurred on two Caribbean cruise ships in late 1974 and early 1975. In all, 697 passengers and 27 crew were affected. Epidemiologic evidence incriminated seafoods served on the ships as the vehicles of transmission. The seafoods were probably contaminated by V. parahaemolyticus after cooking in seawater from the ships' internal seawater distribution systems. Use of seawater in foodhandling areas was discontinued, and no further outbreaks occurred. PMID:433918

  19. The Winnowing: Establishing the Squid-Vibrio Symbiosis

    NSDL National Science Digital Library

    Spencer V. Nyholm

    This Nature Reviews Microbiology article examines the symbiosis between the squid Euprymna scolopes and its luminous bacterial symbiont, Vibrio fischeri. Using image-rich illustrations, it depicts the progression of light-organ colonization as a series of steps and discusses the advent of genomic approaches used to study this model system. A subscription is required to access the full-text version of this article.

  20. Comparison of genome structures of vibrios, bacteria possessing two chromosomes.

    PubMed

    Tagomori, Kenichi; Iida, Tetsuya; Honda, Takeshi

    2002-08-01

    Vibrios are gram-negative gamma-proteobacteria which are ubiquitous in marine and estuarine environments. Recently, we demonstrated that some, if not all, Vibrio species have two circular chromosomes. The whole genome sequence of Vibrio cholerae N16961 has been reported. In this study, we constructed a physical and genetic map of the genome of Kanagawa phenomenon-positive Vibrio parahaemolyticus strain KX-V237 and compared it with those of V. parahaemolyticus AQ4673 and V. cholerae N16961. The genome of KX-V237 comprised two circular chromosomes (3.3 and 1.9 Mb), similar to the structure of the AQ4673 genome. The relative positions of the genes on the genomes were well conserved in the two strains, but a large inversion on the large chromosomes, probably symmetric around the replication origin, was suggested. Although the sizes of the large chromosomes of KX-V237 and V. cholerae N16961 were similar, the sizes of the small chromosomes were very different. Unlike N16961, the superintegron of KX-V237 was located on the large chromosome. Comparison of the genetic maps of the chromosomes of KX-V237 and V. cholerae N16961 revealed that most of the open reading frames (ORFs) present on the large chromosome of the V. cholerae strain had homologues on the large chromosome of the V. parahaemolyticus strain and that most of the ORFs on the small chromosome of N16961 were present on the small chromosome of KX-V237. The difference in the orders of the ORFs on the chromosomes of N16961 and KX-V237 implies that numerous and frequent genetic exchanges have occurred intrachromosomally rather than interchromosomally. PMID:12142404

  1. Cyclic Diguanylate Regulates Vibrio cholerae Virulence Gene Expression

    Microsoft Academic Search

    Anna D. Tischler; Andrew Camilli

    2005-01-01

    The cyclic dinucleotide second messenger cyclic diguanylate (c-diGMP) has been implicated in regulation of cell surface properties in several bacterial species, including Vibrio cholerae. Expression of genes required for V. cholerae biofilm formation is activated by an increased intracellular c-diGMP concentration. The response regulator VieA, which contains a domain responsible for degradation of c-diGMP, is required to maintain a low

  2. Immunofluorescent detection of ice-ice disease-promoting bacterial strain Vibrio sp. P11 of the farmed macroalga, Kappaphycus alvarezii (Gigartinales, Rhodophyta).

    PubMed

    Largo; Fukami; Adachi; Nishijima

    1998-08-01

    A specific immunofluorescent probe consisting of polyclonal antibodies was developed to detect a marine bacterium, Vibrio sp. strain P11, which was found in a previous study to promote the ice-ice disease in the cultivated red macroalga, Kappaphycus alvarezii. The method involves a combined application of the fluorescent stains, 4',6-diamidino-2-phenylindole (DAPI) and the P11 PAbs, into a homogenized seaweed sample (<1 g wet wt), which is prediluted to make bacteria countable under an epifluorescence microscope without serious interference from autofluorescing algal debris. The algal tissue homogenate is then filtered through a 0.2-µm-pore size Nuclepore membrane filter, serving as a mounting pad, and viewed using alternating ultraviolet and IB excitation filters to detect total and specific bacteria, respectively, on the same microscopic field, at the same time. The immunofluorescent probe could be used as a valuable tool in studying the infection mechanism of the bacterium in the macroalga in vitro. PMID:9701641

  3. Grimontia indica AK16T, sp. nov., Isolated from a Seawater Sample Reports the Presence of Pathogenic Genes Similar to Vibrio Genus

    PubMed Central

    Singh, Aditya; Vaidya, Bhumika; Khatri, Indu; Srinivas, T. N. R.; Subramanian, Srikrishna; Korpole, Suresh; Pinnaka, Anil Kumar

    2014-01-01

    Grimontia indica strain AK16T sp. nov. is the type strain of G. indica sp. nov. a new species within the genus Grimontia. This strain, whose genome is described here, was isolated from seawater sample collected from southeast coast of Palk Bay, India. G. indica AK16T is a Gram-negative, facultative aerobic rod shaped bacterium. There are only two other strains in the genus Grimontia one of which, Grimontia hollisae CIP 101886T, is a reported human pathogen isolated from human stool sample while the other, ‘Grimontia marina IMCC5001T’, was isolated from a seawater sample. As compared to the pathogenic strain Grimontia hollisae CIP 101886T, the strain AK16T lacks some genes for pathogenesis like the accessory colonization factors AcfA and AcfD, which are required for the colonization of the bacterium in the host body. While it carries some pathogenesis genes like OmpU, which are related to pathogenesis of Vibrio strains. This suggests that the life cycle of AK16T may include some pathogenic interactions with marine animal(s), or it may be an opportunistic pathogen. Study of the Grimontia genus is important because of the severe pathogenic traits exhibited by a member of the genus with only three species reported in total. The study will provide some vital information which may be useful in future clinical studies on the genus. PMID:24465608

  4. Neutralization of radical toxicity by temperature-dependent modulation of extracellular SOD activity in coral bleaching pathogen Vibrio shiloi and its role as a virulence factor.

    PubMed

    Murali, Malliga Raman; Raja, Subramaniya Bharathi; Devaraj, Sivasitambaram Niranjali

    2010-08-01

    Vibrio shiloi is the first and well-documented bacterium which causes coral bleaching, particularly, during summer, when seawater temperature is between 26 and 31 degrees C. Coral bleaching is the disruption of the symbiotic association between coral hosts and their photosynthetic microalgae zooxanthellae. This is either due to lowered resistance in corals to infection or increased virulence of the bacterium at the higher sea surface temperature. The concentration of the oxygen and resulting oxygen radicals produced by the zooxanthellae during photosynthesis are highly toxic to bacteria, which also assist corals in resisting the infection. Hence, in this study we examined the effect of different temperatures on the activity of a novel extracellular SOD in V. shiloi. We also partially characterized the SOD and clearly confirmed that the extracellular SOD produced by V. shiloi is Mn-SOD type, as it was not inhibited by H2O2 or KCN. Performing chemical susceptibility killing assay, we confirmed that extracellular SOD may act as first line of defense for the bacteria against the reactive oxygen species. Since, increased activity of novel Mn-SOD at higher temperature, leads to the neutralization of radical toxicity and facilitates the survival of V. shiloi. Hence, the extracellular Mn-SOD may be considered as a virulence factor. PMID:20512561

  5. A selective and differential medium for Vibrio alginolyticus.

    PubMed

    Chang, C-I; Lee, C-F; Wu, C-C; Cheng, T C; Tsai, J-M; Lin, K-J

    2011-03-01

    In this paper, we present a selective and differential medium, termed Vibrio alginolyticus (VAL) agar, developed for the isolation and identification of V. alginolyticus. The presence of bile salts, high salinity and high incubation temperature allows the selective growth of moderately halophilic Vibrio species. Differentiation of bacteria is achieved by identifying species capable of sucrose fermentation, made visible by the pH indicator bromocresol purple. In this study, all of the 26 strains of V. alginolyticus and only three of the 99 strains representing 30 species (including 19 Vibrio species) other than V. alginolyticus were able to grow in the VAL medium. The remaining three strains could be further differentiated from V. alginolyticus according to colour or the diameter of colonies produced on VAL agar plates. Colonies isolated from shellfish rearing water and infected shrimp through the use of VAL agar plates were all positively identified as V. alginolyticus by conventional tests and 16S rDNA sequencing. The testing of specificity and differentiation capability of VAL shows the potential of the agar as a medium for the primary isolation of V. alginolyticus from pathological and environmental samples. PMID:21306589

  6. Biocompatible capped iron oxide nanoparticles for Vibrio cholerae detection.

    PubMed

    Sharma, Anshu; Baral, Dinesh; Rawat, Kamla; Solanki, Pratima R; Bohidar, H B

    2015-05-01

    We report the studies relating to fabrication of an efficient immunosensor for Vibrio cholerae detection. Magnetite (iron oxide (Fe3O4)) nanoparticles (NPs) have been synthesized by the co-precipitation method and capped by citric acid (CA). These NPs were electrophoretically deposited onto indium-tin-oxide (ITO)-coated glass substrate and used for immobilization of monoclonal antibodies against Vibrio cholerae (Ab) and bovine serum albumin (BSA) for Vibrio cholerae detection using an electrochemical technique. The structural and morphological studies of Fe3O4 and CA-Fe3O4/ITO were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and dynamic light scattering (DLS) techniques. The average crystalline size of Fe3O4, CA-Fe3O4 nanoparticles obtained were about 29 ± 1 nm and 37 ± 1 nm, respectively. The hydrodynamic radius of the nanoparticles was found to be 77.35 nm (Fe3O4) and 189.51 nm (CA-Fe3O4) by DLS measurement. The results of electrochemical response studies of the fabricated BSA/Ab/CA-Fe2O3/ITO immunosensor exhibits a good detection range of 12.5-500 ng mL(-1) with a low detection limit of 0.32 ng mL(-1), sensitivity 0.03 ?/ng ml(-1) cm(-2), and reproducibility more than 11 times. PMID:25850702

  7. Toxicological responses of the hard clam Meretrix meretrix exposed to excess dissolved iron or challenged by Vibrio parahaemolyticus.

    PubMed

    Zhou, Qing; Zhang, Yong; Peng, Hui-Fang; Ke, Cai-Huan; Huang, He-Qing

    2014-11-01

    The responses of genes encoding defense components such as ferritin, the lipopolysaccharide-induced tumor necrosis factor-alpha factor (LITAF), the inhibitor of nuclear factor-?B (I?B), metallothionein, and glutathione peroxidase were assessed at the transcriptional level in order to investigate the toxicological and immune mechanism of the hard clam Meretrix meretrix (HCMM) following challenge with iron or a bacterium (Vibrio parahaemolyticus). Fe dissolved in natural seawater led to an increase of Fe content in both the hepatopancreas and gill tissue of HCMM between 4 and 15 days of exposure. The ferritin gene responded both transcriptionally as indicated by real-time quantitative PCR and translationally as shown by western blotting results to iron exposure and both transcriptional and translational ferritin expression in the hepatopancreas had a positive correlation with the concentration of dissolved iron in seawater. Both iron and V. parahaemolyticus exposure triggered immune responses with similar trends in clam tissues. There was a significant post-challenge mRNA expression of LITAF and I?B at 3h, ferritin at 24h, and metallothionein and glutathione peroxidase at 48h. This behavior might be linked to their specific functions in physiological processes. These results suggested that similar signaling pathways were triggered during both iron and V. parahaemolyticus challenges. Here, we indicated that the ferritin of Meretrix meretrix was an intermediate in the pathway of iron homeostasis and in its innate immune defense mechanism. PMID:25269138

  8. Vibrio anguillarum Resistance to Rainbow Trout (Oncorhynchus mykiss) Serum: Role of O-Antigen Structure of Lipopolysaccharide

    PubMed Central

    Boesen, Henriette T.; Pedersen, Karl; Larsen, Jens L.; Koch, Claus; Ellis, Anthony E.

    1999-01-01

    The sensitivity of Vibrio anguillarum to the bactericidal effect of rainbow trout serum was investigated with different strains of serogroups O1 and O2a, which are the most frequently found serogroups in clinical outbreaks of vibriosis. All of the V. anguillarum strains were able to activate complement in rainbow trout serum, but smooth strains of V. anguillarum serogroup O1 were resistant to complement-mediated killing in the absence of specific antibodies. In the case of V. anguillarum serogroup O2a strains, 80% of the analyzed strains were resistant to rainbow trout serum even when specific antibodies were present. Analysis of the lipopolysaccharide structures of the tested V. anguillarum strains showed a positive correlation between the O-antigen size of the lipopolysaccharide and resistance to serum killing. The classical complement pathway was responsible for the antibody-dependent serum killing of susceptible V. anguillarum strains. When serum-resistant V. anguillarum serogroup O2a strains were grown in glucose-enriched Lennox L broth, they produced lipopolysaccharide molecules with fewer high-molecular-weight O-antigen units than did strains grown in broth without the addition of glucose. Strains grown in glucose-enriched medium became sensitive to rainbow trout serum killing, indicating that the high-molecular-weight O-antigen side chains prevented the activated complement from damaging the bacterium. PMID:9864229

  9. VasH Is a Transcriptional Regulator of the Type VI Secretion System Functional in Endemic and Pandemic Vibrio cholerae?†

    PubMed Central

    Kitaoka, Maya; Miyata, Sarah T.; Brooks, Teresa M.; Unterweger, Daniel; Pukatzki, Stefan

    2011-01-01

    The Gram-negative bacterium Vibrio cholerae is the etiological agent of cholera, a disease characterized by the release of high volumes of watery diarrhea. Many medically important proteobacteria, including V. cholerae, carry one or multiple copies of the gene cluster that encodes the bacterial type VI secretion system (T6SS) to confer virulence or interspecies competitiveness. Structural similarity and sequence homology between components of the T6SS and the cell-puncturing device of T4 bacteriophage suggest that the T6SS functions as a molecular syringe to inject effector molecules into prokaryotic and eukaryotic target cells. Although our understanding of how the structural T6SS apparatus assembles is developing, little is known about how this system is regulated. Here, we report on the contribution of the activator of the alternative sigma factor 54, VasH, as a global regulator of the V. cholerae T6SS. Using bioinformatics and mutational analyses, we identified domains of the VasH polypeptide that are essential for its ability to initiate transcription of T6SS genes and established a universal role for VasH in endemic and pandemic V. cholerae strains. PMID:21949076

  10. Testing the toxicity of influents to activated sludge plants with the Vibrio fischeri bioassay utilising a sludge matrix.

    PubMed

    Hoffmann, C; Christofi, N

    2001-10-01

    To protect the bioceonosis within activated sludge, a method of predicting the toxic effect of influents to the biological treatment stage of waste water treatment plants, based on DIN method 38412 L 34, has been developed. A population of the luminescent marine bacterium Vibrio fischeri was incorporated into a sludge testing matrix derived from a model laboratory and real activated sludge plants. The sludge was challenged with different concentrations of pure toxicants and complex aqueous samples, and light output by V. fischeri monitored. The results were compared to toxicant testing in the absence of sludge (standard test). The modified method was found to be less sensitive for some toxicants tested than the standard DIN and other bioluminescent tests, but considered more realistic as it provides buffering and takes into account sorption which can affect the sensitivity of the test towards some compounds. The method is comparable in terms of ease of use, speed, reproducibility and cost effectiveness to standard V. fischeri luminescence methods. PMID:11594029

  11. Solar-photocatalytic disinfection of Vibrio cholerae by using Ag@ZnO core-shell structure nanocomposites.

    PubMed

    Das, Sourav; Sinha, Sayantan; Suar, Mrutyunjay; Yun, Soon-Il; Mishra, Amrita; Tripathy, Suraj K

    2015-01-01

    Disinfection of Gram-negative bacterium Vibrio cholerae 569B in aqueous matrix by solar-photocatalysis mediated by Ag@ZnO core-shell structure nanocomposite particles was investigated. Silver nanoparticles are synthesized by the reduction of silver perchlorate followed by precipitation of zinc oxide shell and are employed in the photocatalytic disinfection of the model pathogen. Effect of photocatalyst loading and reaction temperature on the disinfection kinetics was studied. Disinfection efficiency in laboratory as well as real water samples was compared with that of pure-ZnO and TiO2 (Degussa P25). Nanocomposite system has shown optimum disinfection (?98%) at 40-60min of sun-light exposure with a catalyst loading of 0.5mg/L of the reaction solution. The reduction of aquatic bacterial densities by photocatalytically active Ag@ZnO core-shell nanocomposite in presence of natural sun-light may have potential ex situ application in water decontamination at ambient conditions. PMID:25523714

  12. Role of zooplankton diversity in Vibrio cholerae population dynamics and in the incidence of cholera in the Bangladesh Sundarbans.

    PubMed

    de Magny, Guillaume Constantin; Mozumder, Pronob K; Grim, Christopher J; Hasan, Nur A; Naser, M Niamul; Alam, Munirul; Sack, R Bradley; Huq, Anwar; Colwell, Rita R

    2011-09-01

    Vibrio cholerae, a bacterium autochthonous to the aquatic environment, is the causative agent of cholera, a severe watery, life-threatening diarrheal disease occurring predominantly in developing countries. V. cholerae, including both serogroups O1 and O139, is found in association with crustacean zooplankton, mainly copepods, and notably in ponds, rivers, and estuarine systems globally. The incidence of cholera and occurrence of pathogenic V. cholerae strains with zooplankton were studied in two areas of Bangladesh: Bakerganj and Mathbaria. Chitinous zooplankton communities of several bodies of water were analyzed in order to understand the interaction of the zooplankton population composition with the population dynamics of pathogenic V. cholerae and incidence of cholera. Two dominant zooplankton groups were found to be consistently associated with detection of V. cholerae and/or occurrence of cholera cases, namely, rotifers and cladocerans, in addition to copepods. Local differences indicate there are subtle ecological factors that can influence interactions between V. cholerae, its plankton hosts, and the incidence of cholera. PMID:21764957

  13. The Vibrio cholerae quorum-sensing autoinducer CAI-1: analysis of the biosynthetic enzyme CqsA

    SciTech Connect

    Kelly, R.; Bolitho, M; Higgins, D; Lu, W; Ng, W; Jeffrey, P; Rabinowitz, J; Semmelhack, M; Hughson, F; Bassler, B

    2009-01-01

    Vibrio cholerae, the bacterium that causes the disease cholera, controls virulence factor production and biofilm development in response to two extracellular quorum-sensing molecules, called autoinducers. The strongest autoinducer, called CAI-1 (for cholera autoinducer-1), was previously identified as (S)-3-hydroxytridecan-4-one. Biosynthesis of CAI-1 requires the enzyme CqsA. Here, we determine the CqsA reaction mechanism, identify the CqsA substrates as (S)-2-aminobutyrate and decanoyl coenzyme A, and demonstrate that the product of the reaction is 3-aminotridecan-4-one, dubbed amino-CAI-1. CqsA produces amino-CAI-1 by a pyridoxal phosphate-dependent acyl-CoA transferase reaction. Amino-CAI-1 is converted to CAI-1 in a subsequent step via a CqsA-independent mechanism. Consistent with this, we find cells release {ge}100 times more CAI-1 than amino-CAI-1. Nonetheless, V. cholerae responds to amino-CAI-1 as well as CAI-1, whereas other CAI-1 variants do not elicit a quorum-sensing response. Thus, both CAI-1 and amino-CAI-1 have potential as lead molecules in the development of an anticholera treatment.

  14. Predicting the ecotoxicity of ionic liquids towards Vibrio fischeri using genetic function approximation and least squares support vector machine.

    PubMed

    Ma, Shuying; Lv, Min; Deng, Fangfang; Zhang, Xiaoyun; Zhai, Honglin; Lv, Wenjuan

    2015-02-11

    Ionic liquids (ILs) are widely used in industrial production for their unique physicochemical properties, and they are even regarded as green solvents. However, the recent study showed ILs might pose a potential risk to aquatic ecosystems. In the present work, the quantitative structure-activity relationship (QSAR) models, including genetic function approximation (GFA) and least squares support vector machine (LSSVM) were developed for predicting the ecotoxicity of ILs towards the marine bacterium Vibrio fischeri based on the descriptors calculated from cations and anions. Five descriptors were selected by GFA and used to develop the linear model. From the discussion of descriptors, the cation structure was the main factor to the toxicity, which mainly depended on the size, lipophilic, and 3D molecular structure of cations. In order to capture the nonlinear nature, the LSSVM model was also built for more accurately predicting the ecotoxicity. The GFA and LSSVM models were performed the rigorous internal and external validation, further verifying these models with excellent robustness and predictive ability. Therefore, both of models can be used for the prediction of the ecotoxicity of newly synthesized and untested ILs, and can provide reference information and theoretical guidance for designing and synthesizing safer and more eco-friendly ILs. PMID:25464300

  15. Activity of Alkyl Hydroperoxide Reductase Subunit C1 and C2 of Vibrio parahaemolyticus against Different Peroxides.

    PubMed

    Chung, Chun-Hui; Ma, Tsung-Yong; Fen, Shin-Yuan; Wong, Hin-Chung

    2014-09-19

    Alkylhydroperoxide reductase subunit C (ahpC) gene functions were characterized in Vibrio parahaemolyticus, a commonly occurring marine foodborne enteropathogenic bacterium. Two ahpC genes, ahpC1 (VPA1683) and ahpC2 (VP0580), encoded putative 2-cysteine peroxiredoxins, which are highly similar to the homologous proteins of V. vulnificus. The responses of deletion mutants of ahpC genes to various peroxides were compared with and without gene complementation and at different incubation temperatures. The growth of the ahpC1 and ahpC12 double mutants in liquid medium was significantly inhibited by organic peroxides, cumene hydroperoxide and tert-butyl hydroperoxide. However, inhibition was higher at 12°C and 22°C then at 37°C. Inhibiting effects were prevented by the complementary ahpC1 gene. Inconsistent detoxification of H2O2 by ahpC genes was demonstrated in an agar medium but not in a liquid medium. Complementation with an ahpC2 gene partially restored the peroxidase effect in the double ahpC12 mutant at 22°C. This investigation reveals that ahpC1 is the chief peroxidase gene that acts against organic peroxides in V. parahaemolyticus and that the function of the ahpC genes is influenced by incubation temperature. PMID:25239899

  16. Development of a Real-Time Resistance Measurement for Vibrio parahaemolyticus Detection by the Lecithin-Dependent Hemolysin Gene

    PubMed Central

    Xiang, Guiming; Pu, Xiaoyun; Jiang, Dongneng; Liu, Linlin; Liu, Chang; Liu, Xiaobo

    2013-01-01

    The marine bacterium Vibrio parahaemolyticus (V. parahaemolyticus) causes gastroenteritis in humans via the ingestion of raw or undercooked contaminated seafood, and early diagnosis and prompt treatment are important for the prevention of V. parahaemolyticus-related diseases. In this study, a real-time resistance measurement based on loop-mediated isothermal amplification (LAMP), electrochemical ion bonding (Crystal violet and Mg2+), real-time monitoring, and derivative analysis was developed. V. parahaemolyticus DNA was first amplified by LAMP, and the products (DNA and pyrophosphate) represented two types of negative ions that could combine with a positive dye (Crystal violet) and positive ions (Mg2+) to increase the resistance of the reaction liquid. This resistance was measured in real-time using a specially designed resistance electrode, thus permitting the quantitative detection of V. parahaemolyticus. The results were obtained in 1–2 hours, with a minimum bacterial density of 10 CFU.mL?1 and high levels of accuracy (97%), sensitivity (96.08%), and specificity (97.96%) when compared to cultivation methods. Therefore, this simple and rapid method has a potential application in the detection of V. parahaemolyticus on a gene chip or in point-of-care testing. PMID:23991096

  17. Sediment and Vegetation as Reservoirs of Vibrio vulnificus in the Tampa Bay Estuary and Gulf of Mexico.

    PubMed

    Chase, Eva; Young, Suzanne; Harwood, Valerie J

    2015-04-01

    The opportunistic pathogen Vibrio vulnificus occurs naturally in estuarine habitats and is readily cultured from water and oysters under warm conditions but infrequently at ambient conditions of <15°C. The presence of V. vulnificus in other habitats, such as sediments and aquatic vegetation, has been explored much less frequently. This study investigated the ecology of V. vulnificus in water by culture and quantitative PCR (qPCR) and in sediment, oysters, and aquatic vegetation by culture. V. vulnificus samples were taken from five sites around Tampa Bay, FL. Levels determined by qPCR and culture were significantly correlated (P = 0.0006; r = 0.352); however, V. vulnificus was detected significantly more frequently by qPCR (85% of all samples) compared to culture (43%). Culturable V. vulnificus bacteria were recovered most frequently from oyster samples (70%), followed by vegetation and sediment (?50%) and water (43%). Water temperature, which ranged from 18.5 to 33.4°C, was positively correlated with V. vulnificus concentrations in all matrices but sediments. Salinity, which ranged from 1 to 35 ppt, was negatively correlated with V. vulnificus levels in water and sediments but not in other matrices. Significant interaction effects between matrix and temperature support the hypothesis that temperature affects V. vulnificus concentrations differently in different matrices and that sediment habitats may serve as seasonal reservoirs for V. vulnificus. V. vulnificus levels in vegetation have not been previously measured and reveal an additional habitat for this autochthonous estuarine bacterium. PMID:25636843

  18. Role of Zooplankton Diversity in Vibrio cholerae Population Dynamics and in the Incidence of Cholera in the Bangladesh Sundarbans ?

    PubMed Central

    de Magny, Guillaume Constantin; Mozumder, Pronob K.; Grim, Christopher J.; Hasan, Nur A.; Naser, M. Niamul; Alam, Munirul; Sack, R. Bradley; Huq, Anwar; Colwell, Rita R.

    2011-01-01

    Vibrio cholerae, a bacterium autochthonous to the aquatic environment, is the causative agent of cholera, a severe watery, life-threatening diarrheal disease occurring predominantly in developing countries. V. cholerae, including both serogroups O1 and O139, is found in association with crustacean zooplankton, mainly copepods, and notably in ponds, rivers, and estuarine systems globally. The incidence of cholera and occurrence of pathogenic V. cholerae strains with zooplankton were studied in two areas of Bangladesh: Bakerganj and Mathbaria. Chitinous zooplankton communities of several bodies of water were analyzed in order to understand the interaction of the zooplankton population composition with the population dynamics of pathogenic V. cholerae and incidence of cholera. Two dominant zooplankton groups were found to be consistently associated with detection of V. cholerae and/or occurrence of cholera cases, namely, rotifers and cladocerans, in addition to copepods. Local differences indicate there are subtle ecological factors that can influence interactions between V. cholerae, its plankton hosts, and the incidence of cholera. PMID:21764957

  19. Rickettsia-like Bacterium Associated with Pierce's Disease of Grapes

    Microsoft Academic Search

    Donald L. Hopkins; Hilton H. Mollenhauer

    1973-01-01

    A pleomorphic bacterium was observed by electron microscopy in grape plants infected with Pierce's disease. The organism was located in xylem tissue, and its occurrence was closely associated with symptoms of Pierce's disease. The bacterium resembled a rickettsia in morphology, in its failure to grow on cell-free media, and in its sensitivity to tetracycline antibiotics.

  20. Ratoon Stunting Disease of Sugarcane: Isolation of the Causal Bacterium

    Microsoft Academic Search

    Michael J. Davis; A. Graves Gillaspie; Russell W. Harris; Roger H. Lawson

    1980-01-01

    A small coryneform bacterium was consistently isolated from sugarcane with ratoon stunting disease and shown to be the causal agent. A similar bacterium was isolated from Bermuda grass. Both strains multiplied in sugarcane and Bermuda grass, but the Bermuda grass strain did not incite the symptoms of ratoon stunting disease in sugarcane. Shoot growth in Bermuda grass was retarded by

  1. Effect of temperature on growth of Vibrio parahaemolyticus [corrected] and Vibrio vulnificus in flounder, salmon sashimi and oyster meat.

    PubMed

    Kim, Yoo Won; Lee, Soon Ho; Hwang, In Gun; Yoon, Ki Sun

    2012-12-01

    Vibrio parahaemolyticus and Vibrio vulnificus are the major pathogenic Vibrio species which contaminate ready-to-eat seafood. The purpose of this study was to evaluate the risk of human illness resulting from consumption of ready-to-eat seafood such as sashimi and raw oyster meat due to the presence of V. parahaemolyticus and V. vulnificus. We compared the growth kinetics of V. parahaemolyticus and V. vulnificus strains in broth and ready-to-eat seafood, including flounder and salmon sashimi, as a function of temperature. The growth kinetics of naturally occurring V. vulnificus in raw oyster meat was also evaluated. The minimum growth temperatures of V. parahaemolyticus and V. vulnificus in broth were 13 °C and 11 °C, respectively. Overall, significant differences in lag time (LT) and specific growth rate (SGR) values between flounder and salmon sashimi were observed at temperatures ranging from 13 °C to 30 °C (p < 0.05). The growth of naturally occurring V. vulnificus reached stationary phase at ~4 log CFU/g in oysters, regardless of the storage temperature. This data indicates that the population of V. vulnificus in oysters did not reach the maximum population density as observed in the broth, where growth of V. vulnificus and V. parahaemolyticus isolated from oysters grew up to >8 log CFU/mL. PMID:23330227

  2. Gene sequences of the pil operon reveal relationships between symbiotic strains of Vibrio

    E-print Network

    McFall-Ngai, Margaret

    Gene sequences of the pil operon reveal relationships between symbiotic strains of Vibrio fischeri the bobtail squid Euprymna scolopes (Mollusca: Cephalopoda) and Vibrio fischeri bacteria has been a well-negative bacteria with eukaryotic hosts. To investigate variation amongst pil genes of closely related strains

  3. Whole-Genome Sequence of Quorum-Sensing Vibrio tubiashii Strain T33

    PubMed Central

    Izzati Mohamad, Nur; Yin, Wai-Fong

    2015-01-01

    Vibrio tubiashii strain T33 was isolated from the coastal waters of Morib, Malaysia, and was shown to possess quorum-sensing activity similar to that of its famous relative Vibrio fischeri. Here, the assembly and annotation of its genome are presented. PMID:25555738

  4. Abstract The recent discovery that the fish pathogen Vibrio salmonicida is closely related to the luminous

    E-print Network

    McFall-Ngai, Margaret

    Abstract The recent discovery that the fish pathogen Vibrio salmonicida is closely related salmon (Salmo salar), rainbow trout (Oncorhynchus mykiss), and cod (Gadus morhua) (Egidius 1986; Wiik et luminescence in the cold-water fish pathogen Vibrio salmonicida Arch Microbiol (1999) 171:205­209 © Springer

  5. A Tetrodotoxin-Producing Vibrio Strain, LM1, from the Puffer Fish Fugu vermicularis radiatus

    Microsoft Academic Search

    MYOUNG-JA LEE; DONG-YOUN JEONG; WOO-SEONG KIM; HYUN-DAE KIM; CHEORL-HO KIM; WON-WHAN PARK; YONG-HA PARK; KYUNG-SAM KIM; HYUNG-MIN KIM; DONG-SOO KIM

    2000-01-01

    identified as members of the genus Vibrio (21). Also, Simidu et al. (29) demonstrated that many species of marine bacteria, including Vibrio spp. (21), Pseudomonas spp. (33), and actino- mycetes (1), produce TTX. Three individual F. vermicularis radiatus puffer fish (male; body weight, 45 g) were collected at Pusan, Korea, in March 1998, transported live to the laboratory, and maintained

  6. Impact of milk fish farming in the tropics on potentially pathogenic vibrios.

    PubMed

    Reichardt, W T; Reyes, J M; Pueblos, M J; Lluisma, A O

    2013-12-15

    Ratios of sucrose-negative to sucrose-positive vibrios on TCBS agar (suc-/suc+) indicate the abundance of potential human pathogenic non-cholera vibrios in coastal mariculture environments of the Lingayen Gulf (Philippines. In guts of adult maricultured milkfish (Chanos chanos) of suc- vibrios reached extreme peak values ranging between 2 and 545 million per g wet weight. Suc- vibrios outnumbered suc+ vibrios in anoxic sediments, too, and were rarely predominant in coastal waters or in oxidized sediments. Suc-/suc+ ratios in sediments increased toward the mariculture areas with distance from the open sea at decreasing redox potentials. There is circumstantial evidence that suc- vibrios can be dispersed from mariculture areas to adjacent environments including coral reefs. An immediate human health risk by pathogenic Vibrio species is discounted, since milkfish guts contained mainly members of the Enterovibrio group. A representative isolate of these contained proteolytic and other virulence factors, but no genes encoding toxins characteristic of clinical Vibrio species. PMID:24079922

  7. LuxU connects quorum sensing to biofilm formation in Vibrio fischeri

    E-print Network

    McFall-Ngai, Margaret

    LuxU connects quorum sensing to biofilm formation in Vibrio fischeri Valerie A. Ray and Karen L, USA. Summary Biofilm formation by Vibrio fischeri is a complex process involving multiple regulators polysaccha- ride (syp) locus. To identify other regulators of biofilm formation in V. fischeri, we screened

  8. CHITINASE DETERMINANTS OF 'VIBRIO VULNIFICUS': GENE CLONING AND APPLICATIONS OF A CHITINASE PROBE

    EPA Science Inventory

    To initiate study of the genetic control of chitinolytic activity in vibrios, the chitobiase gene was isolated by cloning chromosomal DNA prepared from Vibrio vulnificus. Chimeric plasmids were constructed from Sau3A I partial digests of chromosomal DNA by ligating 5 to 15-Kiloba...

  9. Specific Inhibition of Chemiluminescent Activity by Pathogenic Vibrios in Hemocytes of Two Marine Bivalves

    E-print Network

    Paris-Sud XI, Université de

    1 Specific Inhibition of Chemiluminescent Activity by Pathogenic Vibrios in Hemocytes of Two Marine particles were added to the hemocytes and the chemiluminescent (CL) activity of the cells was measured over; Crassostrea gigas; bacteria; chemiluminescence; hemocytes; respiratory burst; Vibrio sp. INTRODUCTION

  10. A SIMPLE FLUOROGENIC METHOD TO ASSESS VIBRIO CHOLERAE AND AEROMONAS HYDROPHILA IN WELL WATER

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We present the colony overlay procedure for peptidases (COPP), a simple, fluorogenic assay for the rapid detection of Vibrio cholerae and Aeromonas hydrophila in fresh well water. Substrate cleavage by enzymes present in Vibrio and Aeromonas species produces fluorescent foci on UV-light irradiated ...

  11. Agrobacterium tumefaciens is a diazotrophic bacterium

    SciTech Connect

    Kanvinde, L.; Sastry, G.R.K. (Univ. of Leeds (England))

    1990-07-01

    This is the first report that Agrobacterium tumefaciens can fix nitrogen in a free-living condition as shown by its abilities to grown on nitrogen-free medium, reduce acetylene to ethylene, and incorporate {sup 15}N supplied as {sup 15}N{sub 2}. As with most other well-characterized diazotrophic bacteria, the presence of NH{sub 4}{sup +} in the medium and aerobic conditions repress nitrogen fixation by A. tumefaciens. The system requires molybdenum. No evidence for nodulation was found with pea, peanut, or soybean plants. Further understanding of the nitrogen-fixing ability of this bacterium, which has always been considered a pathogen, should cast new light on the evolution of a pathogenic versus symbiotic relationship.

  12. [Pathogenic Vibrios in oysters (Crassostrea rhizophorae) served at restaurants in Rio de Janeiro: a public health warning].

    PubMed

    Pereira, Christiane Soares; Viana, Célio Mauro; Rodrigues, Dália dos Prazeres

    2007-01-01

    Forty oyster samples (Crassostrea rhizophorae) served raw in 15 restaurants in the city of Rio de Janeiro were evaluated in order to investigate the presence of Vibrio spp. The oyster samples were analyzed and subjected to enrichment in alkaline peptone water with the addition of 1 and 3% NaCl and incubated at 37 degrees C for 24 hours. Following this, the cultures were seeded onto thiosulfate citrate bile sucrose agar (TCBS) and the suspected colonies were subjected to biochemical characterization. Vibrio parahaemolyticus, Vibrio carchariae, Vibrio alginolyticus and Vibrio vulnificus were the main species (> 60%) isolated from raw oysters. PMID:17653465

  13. Temperature-dependent inhibition of opportunistic Vibrio pathogens by native coral commensal bacteria.

    PubMed

    Frydenborg, Beck R; Krediet, Cory J; Teplitski, Max; Ritchie, Kim B

    2014-02-01

    Bacteria living within the surface mucus layer of corals compete for nutrients and space. A number of stresses affect the outcome of this competition. The interactions between native microorganisms and opportunistic pathogens largely determine the coral holobiont's overall health and fitness. In this study, we tested the hypothesis that commensal bacteria isolated from the mucus layer of a healthy elkhorn coral, Acropora palmata, are capable of inhibition of opportunistic pathogens, Vibrio shiloi AK1 and Vibrio coralliilyticus. These vibrios are known to cause disease in corals and their virulence is temperature dependent. Elevated temperature (30 °C) increased the cell numbers of one commensal and both Vibrio pathogens in monocultures. We further tested the hypothesis that elevated temperature favors pathogenic organisms by simultaneously increasing the fitness of vibrios and decreasing the fitness of commensals by measuring growth of each species within a co-culture over the course of 1 week. In competition experiments between vibrios and commensals, the proportion of Vibrio spp. increased significantly under elevated temperature. We finished by investigating several temperature-dependent mechanisms that could influence co-culture differences via changes in competitive fitness. The ability of Vibrio spp. to utilize glycoproteins found in A. palmata mucus increased or remained stable when exposed to elevated temperature, while commensals' tended to decrease utilization. In both vibrios and commensals, protease activity increased at 30 °C, while chiA expression increased under elevated temperatures for Vibrio spp. These results provide insight into potential mechanisms through which elevated temperature may select for pathogenic bacterial dominance and lead to disease or a decrease in coral fitness. PMID:24370863

  14. Recombinant Production and Characterization of a Highly Active Alkaline Phosphatase from Marine Bacterium Cobetia marina.

    PubMed

    Golotin, Vasily; Balabanova, Larissa; Likhatskaya, Galina; Rasskazov, Valery

    2015-04-01

    The psychrophilic marine bacterium, Cobetia marina, recovered from the mantle tissue of the marine mussel, Crenomytilus grayanus, which contained a gene encoding alkaline phosphatase (AP) with apparent biotechnology advantages. The enzyme was found to be more efficient than its counterparts and showed k cat value 10- to 100-fold higher than those of all known commercial APs. The enzyme did not require the presence of exogenous divalent cations and dimeric state of its molecule for activity. The recombinant enzyme (CmAP) production and purification were optimized with a final recovery of 2 mg of the homogenous protein from 1 L of the transgenic Escherichia coli Rosetta(DE3)/Pho40 cells culture. CmAP displayed a half-life of 16 min at 45 °C and 27 min at 40 °C in the presence of 2 mM EDTA, thus suggesting its relative thermostability in comparison with the known cold-adapted analogues. A high concentration of EDTA in the incubation mixture did not appreciably inhibit CmAP. The enzyme was stable in a wide range of pH (6.0-11.0). CmAP exhibited its highest activity at the reaction temperature of 40-50 °C and pH 9.5-10.3. The structural features of CmAP could be the reason for the increase in its stability and catalytic turnover. We have modeled the CmAP 3D structure on the base of the high-quality experimental structure of the close homologue Vibrio sp. AP (VAP) and mutated essential residues predicted to break Mg(2+) bonds in CmAP. It seems probable that the intrinsically tight binding of catalytic and structural metal ions together with the flexibility of intermolecular and intramolecular links in CmAP could be attributed to the adapted mutualistic lifestyle in oceanic waters. PMID:25260971

  15. Structural characteristics of alkaline phosphatase from the moderately halophilic bacterium Halomonas sp. 593

    PubMed Central

    Arai, Shigeki; Yonezawa, Yasushi; Ishibashi, Matsujiro; Matsumoto, Fumiko; Adachi, Motoyasu; Tamada, Taro; Tokunaga, Hiroko; Blaber, Michael; Tokunaga, Masao; Kuroki, Ryota

    2014-01-01

    Alkaline phosphatase (AP) from the moderate halophilic bacterium Halomonas sp. 593 (HaAP) catalyzes the hydrolysis of phosphomonoesters over a wide salt-concentration range (1–4?M NaCl). In order to clarify the structural basis of its halophilic characteristics and its wide-range adaptation to salt concentration, the tertiary structure of HaAP was determined by X-ray crystallography to 2.1?Å resolution. The unit cell of HaAP contained one dimer unit corresponding to the biological unit. The monomer structure of HaAP contains a domain comprised of an 11-stranded ?-sheet core with 19 surrounding ?-helices similar to those of APs from other species, and a unique ‘crown’ domain containing an extended ‘arm’ structure that participates in formation of a hydrophobic cluster at the entrance to the substrate-binding site. The HaAP structure also displays a unique distribution of negatively charged residues and hydrophobic residues in comparison to other known AP structures. AP from Vibrio sp. G15-21 (VAP; a slight halophile) has the highest similarity in sequence (70.0% identity) and structure (C? r.m.s.d. of 0.82?Å for the monomer) to HaAP. The surface of the HaAP dimer is substantially more acidic than that of the VAP dimer (144 exposed Asp/Glu residues versus 114, respectively), and thus may enable the solubility of HaAP under high-salt conditions. Conversely, the monomer unit of HaAP formed a substantially larger hydrophobic interior comprising 329 C atoms from completely buried residues, whereas that of VAP comprised 264 C atoms, which may maintain the stability of HaAP under low-salt conditions. These characteristics of HaAP may be responsible for its unique functional adaptation permitting activity over a wide range of salt concentrations. PMID:24598750

  16. Structural characteristics of alkaline phosphatase from the moderately halophilic bacterium Halomonas sp. 593.

    PubMed

    Arai, Shigeki; Yonezawa, Yasushi; Ishibashi, Matsujiro; Matsumoto, Fumiko; Adachi, Motoyasu; Tamada, Taro; Tokunaga, Hiroko; Blaber, Michael; Tokunaga, Masao; Kuroki, Ryota

    2014-03-01

    Alkaline phosphatase (AP) from the moderate halophilic bacterium Halomonas sp. 593 (HaAP) catalyzes the hydrolysis of phosphomonoesters over a wide salt-concentration range (1-4?M NaCl). In order to clarify the structural basis of its halophilic characteristics and its wide-range adaptation to salt concentration, the tertiary structure of HaAP was determined by X-ray crystallography to 2.1?Å resolution. The unit cell of HaAP contained one dimer unit corresponding to the biological unit. The monomer structure of HaAP contains a domain comprised of an 11-stranded ?-sheet core with 19 surrounding ?-helices similar to those of APs from other species, and a unique `crown' domain containing an extended `arm' structure that participates in formation of a hydrophobic cluster at the entrance to the substrate-binding site. The HaAP structure also displays a unique distribution of negatively charged residues and hydrophobic residues in comparison to other known AP structures. AP from Vibrio sp. G15-21 (VAP; a slight halophile) has the highest similarity in sequence (70.0% identity) and structure (C(?) r.m.s.d. of 0.82?Å for the monomer) to HaAP. The surface of the HaAP dimer is substantially more acidic than that of the VAP dimer (144 exposed Asp/Glu residues versus 114, respectively), and thus may enable the solubility of HaAP under high-salt conditions. Conversely, the monomer unit of HaAP formed a substantially larger hydrophobic interior comprising 329 C atoms from completely buried residues, whereas that of VAP comprised 264 C atoms, which may maintain the stability of HaAP under low-salt conditions. These characteristics of HaAP may be responsible for its unique functional adaptation permitting activity over a wide range of salt concentrations. PMID:24598750

  17. A novel eliminase from a marine bacterium that degrades hyaluronan and chondroitin sulfate.

    PubMed

    Han, Wenjun; Wang, Wenshuang; Zhao, Mei; Sugahara, Kazuyuki; Li, Fuchuan

    2014-10-01

    Lyases cleave glycosaminoglycans (GAGs) in an eliminative mechanism and are important tools for the structural analysis and oligosaccharide preparation of GAGs. Various GAG lyases have been identified from terrestrial but not marine organisms even though marine animals are rich in GAGs with unique structures and functions. Herein we isolated a novel GAG lyase for the first time from the marine bacterium Vibrio sp. FC509 and then recombinantly expressed and characterized it. It showed strong lyase activity toward hyaluronan (HA) and chondroitin sulfate (CS) and was designated as HA and CS lyase (HCLase). It exhibited the highest activities to both substrates at pH 8.0 and 0.5 m NaCl at 30 °C. Its activity toward HA was less sensitive to pH than its CS lyase activity. As with most other marine enzymes, HCLase is a halophilic enzyme and very stable at temperatures from 0 to 40 °C for up to 24 h, but its activity is independent of divalent metal ions. The specific activity of HCLase against HA and CS reached a markedly high level of hundreds of thousands units/mg of protein under optimum conditions. The HCLase-resistant tetrasaccharide ?(4,5)HexUA?1-3GalNAc(6-O-sulfate)?1-4GlcUA(2-O-sulfate)?1-3GalNAc(6-O-sulfate) was isolated from CS-D, the structure of which indicated that HCLase could not cleave the galactosaminidic linkage bound to 2-O-sulfated d-glucuronic acid (GlcUA) in CS chains. Site-directed mutagenesis indicated that HCLase may work via a catalytic mechanism in which Tyr-His acts as the Brønsted base and acid. Thus, the identification of HCLase provides a useful tool for HA- and CS-related research and applications. PMID:25122756

  18. Desulfonatronum Thiodismutans sp. nov., a Novel Alkaliphilic, Sulfate-reducing Bacterium Capable of Lithoautotrophic Growth

    NASA Technical Reports Server (NTRS)

    Pikuta, Elena V.; Hoover, Richard B.; Bej, Asim K.; Marsic, Damien; Whitman, William B.; Cleland, David; Krader, Paul

    2003-01-01

    A novel alkaliphilic, sulfate-reducing bacterium, strain MLF1(sup T), was isolated from sediments of soda Mono Lake, California. Gram-negative vibrio-shaped cells were observed, which were 0.6-0.7 x 1.2-2.7 microns in size, motile by a single polar flagellum and occurred singly, in pairs or as short spirilla. Growth was observed at 15-48 C (optimum, 37 C), > 1-7 % NaCI, w/v (optimum, 3%) and pH 8.0-10.0 (optimum, 9.5). The novel isolate is strictly alkaliphilic, requires a high concentration of carbonate in the growth medium and is obligately anaerobic and catalase-negative. As electron donors, strain MLF1(sup T) uses hydrogen, formate and ethanol. Sulfate, sulfite and thiosulfate (but not sulfur or nitrate) can be used as electron acceptors. The novel isolate is a lithoheterotroph and a facultative lithoautotroph that is able to grow on hydrogen without an organic source of carbon. Strain MLF1(sup T) is resistant to kanamycin and gentamicin, but sensitive to chloramphenicol and tetracycline. The DNA G+C content is 63.0 mol% (HPLC). DNA-DNA hybridization with the most closely related species, Desulfonatronum lacustre Z-7951(sup T), exhibited 51 % homology. Also, the genome size (1.6 x 10(exp 9) Da) and T(sub m) value of the genomic DNA (71 +/- 2 C) for strain MLF1(sup T) were significantly different from the genome size (2.1 x 10(exp 9) Da) and T(sub m) value (63 +/- 2 C) for Desulfonatronum lacustre Z-7951(sup T). On the basis of physiological and molecular properties, the isolate was considered to be a novel species of the genus Desulfonatronum, for which the name Desulfonatronum thiodismutans sp. nov. is proposed (the type strain is MLF1(sup T) = ATCC BAA-395(sup T) = DSM 14708(sup T)).

  19. Ecology of Vibrio parahaemolyticus and Vibrio vulnificus in the Coastal and Estuarine Waters of Louisiana, Maryland, Mississippi, and Washington (United States)

    PubMed Central

    Bowers, John C.; Griffitt, Kimberly J.; Molina, Vanessa; Clostio, Rachel W.; Pei, Shaofeng; Laws, Edward; Paranjpye, Rohinee N.; Strom, Mark S.; Chen, Arlene; Hasan, Nur A.; Huq, Anwar; Noriea, Nicholas F.; Grimes, D. Jay; Colwell, Rita R.

    2012-01-01

    Vibrio parahaemolyticus and Vibrio vulnificus, which are native to estuaries globally, are agents of seafood-borne or wound infections, both potentially fatal. Like all vibrios autochthonous to coastal regions, their abundance varies with changes in environmental parameters. Sea surface temperature (SST), sea surface height (SSH), and chlorophyll have been shown to be predictors of zooplankton and thus factors linked to vibrio populations. The contribution of salinity, conductivity, turbidity, and dissolved organic carbon to the incidence and distribution of Vibrio spp. has also been reported. Here, a multicoastal, 21-month study was conducted to determine relationships between environmental parameters and V. parahaemolyticus and V. vulnificus populations in water, oysters, and sediment in three coastal areas of the United States. Because ecologically unique sites were included in the study, it was possible to analyze individual parameters over wide ranges. Molecular methods were used to detect genes for thermolabile hemolysin (tlh), thermostable direct hemolysin (tdh), and tdh-related hemolysin (trh) as indicators of V. parahaemolyticus and the hemolysin gene vvhA for V. vulnificus. SST and suspended particulate matter were found to be strong predictors of total and potentially pathogenic V. parahaemolyticus and V. vulnificus. Other predictors included chlorophyll a, salinity, and dissolved organic carbon. For the ecologically unique sites included in the study, SST was confirmed as an effective predictor of annual variation in vibrio abundance, with other parameters explaining a portion of the variation not attributable to SST. PMID:22865080

  20. Ecology of Vibrio parahaemolyticus and Vibrio vulnificus in the coastal and estuarine waters of Louisiana, Maryland, Mississippi, and Washington (United States).

    PubMed

    Johnson, Crystal N; Bowers, John C; Griffitt, Kimberly J; Molina, Vanessa; Clostio, Rachel W; Pei, Shaofeng; Laws, Edward; Paranjpye, Rohinee N; Strom, Mark S; Chen, Arlene; Hasan, Nur A; Huq, Anwar; Noriea, Nicholas F; Grimes, D Jay; Colwell, Rita R

    2012-10-01

    Vibrio parahaemolyticus and Vibrio vulnificus, which are native to estuaries globally, are agents of seafood-borne or wound infections, both potentially fatal. Like all vibrios autochthonous to coastal regions, their abundance varies with changes in environmental parameters. Sea surface temperature (SST), sea surface height (SSH), and chlorophyll have been shown to be predictors of zooplankton and thus factors linked to vibrio populations. The contribution of salinity, conductivity, turbidity, and dissolved organic carbon to the incidence and distribution of Vibrio spp. has also been reported. Here, a multicoastal, 21-month study was conducted to determine relationships between environmental parameters and V. parahaemolyticus and V. vulnificus populations in water, oysters, and sediment in three coastal areas of the United States. Because ecologically unique sites were included in the study, it was possible to analyze individual parameters over wide ranges. Molecular methods were used to detect genes for thermolabile hemolysin (tlh), thermostable direct hemolysin (tdh), and tdh-related hemolysin (trh) as indicators of V. parahaemolyticus and the hemolysin gene vvhA for V. vulnificus. SST and suspended particulate matter were found to be strong predictors of total and potentially pathogenic V. parahaemolyticus and V. vulnificus. Other predictors included chlorophyll a, salinity, and dissolved organic carbon. For the ecologically unique sites included in the study, SST was confirmed as an effective predictor of annual variation in vibrio abundance, with other parameters explaining a portion of the variation not attributable to SST. PMID:22865080

  1. VibrioBase: A MALDI-TOF MS database for fast identification of Vibrio spp. that are potentially pathogenic in humans.

    PubMed

    Erler, René; Wichels, Antje; Heinemeyer, Ernst-August; Hauk, Gerhard; Hippelein, Martin; Reyes, Nadja Torres; Gerdts, Gunnar

    2015-02-01

    Mesophilic marine bacteria of the family Vibrionaceae, specifically V. cholerae, V. parahaemolyticus and V. vulnificus, are considered to cause severe illness in humans. Due to climate-change-driven temperature increases, higher Vibrio abundances and infections are predicted for Northern Europe, which in turn necessitates environmental surveillance programs to evaluate this risk. We propose that whole-cell matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) profiling is a promising tool for the fast and reliable species classification of environmental isolates. Because the reference database does not contain sufficient Vibrio spectra we generated the VibrioBase database in this study. Mass spectrometric data were generated from 997 largely environmental strains and filed in this new database. MALDI-TOF MS clusters were assigned based on the species classification obtained by analysis of partial rpoB (RNA polymerase beta-subunit) sequences. The affiliation of strains to species-specific clusters was consistent in 97% of all cases using both approaches, and the extended VibrioBase generated more specific species identifications with higher matching scores compared to the commercially available database. Therefore, we have made the VibrioBase database freely accessible, which paves the way for detailed risk assessment studies of potentially pathogenic Vibrio spp. from marine environments. PMID:25466918

  2. Isolation and characterization of an anaerobic chlorophenol-transforming bacterium.

    PubMed Central

    Madsen, T; Licht, D

    1992-01-01

    An obligately anaerobic bacterium which transforms several chlorinated phenols was isolated. Dechlorination of the substituents ortho to the phenolic OH group was preferred, while removal of a meta-substituted chlorine was observed only with 3,5-dichlorophenol. The bacterium was a gram-positive, endospore-forming, motile, slightly curved rod. Sulfate was not reduced. Nitrate was reduced via nitrite to ammonium. The bacterium is related to the genus Clostridium. The highest growth rate was obtained in a medium containing pyruvate and yeast extract. Pyruvate supported growth as the sole source of carbon, and the fermentation of pyruvate produced almost equimolar amounts of acetate. Images PMID:1444400

  3. Wound infections caused by Vibrio vulnificus and other marine bacteria.

    PubMed Central

    Oliver, J. D.

    2005-01-01

    Infections caused by Vibrio vulnificus were first reported in 1979 by Blake et al. of the US Centers for Disease Control. At that time described as a 'rare, unnamed halophilic lactose-fermenting Vibrio species', V. vulnificus has emerged as the most virulent foodborne pathogen in the United States with a hospitalization rate of 0.910 and a case-fatality rate of 0.390. It is in addition a significant cause of potentially life-threatening wound infections. Infections following ingestion of raw or undercooked seafood, commonly raw oysters, can lead to a primary septicaemia with a fatality rate of 50-60%. An unusual symptom, occurring in 69% of 274 cases reviewed by Oliver, is the development of secondary lesions, typically on the extremities, which are generally severe (often a necrotizing fasciitis) and require tissue debridement or amputation. These cases occur almost exclusively in males over the age of 50 years. Interestingly, this gender specificity has been found to be due to the female hormone oestrogen, which in some manner provides protection against the lethal V. vulnificus endotoxin. Further, most cases occur in persons with certain underlying diseases which are either immunocompromising or which lead to elevated serum iron levels (e.g. liver cirrhosis, chronic hepatitis, haemochromatosis). V. vulnificus infections resulting in primary septicaemia have been extensively studied, and the subject of several reviews. This review concentrates on the wound infections caused by this marine bacterial pathogen, including the more recently described biotypes 2 and 3, with brief discussions of those caused by other marine vibrios, and the increasingly reported wound/skin infections caused by Mycobacterium marinum, Erysipelothrix rhusiopathiae, and Aeromnonas hydrophila. PMID:15962544

  4. Molecular analysis of the emergence of pandemic Vibrio parahaemolyticus

    PubMed Central

    Boyd, E Fidelma; Cohen, Ana Luisa V; Naughton, Lynn M; Ussery, David W; Binnewies, Tim T; Stine, O Colin; Parent, Michelle A

    2008-01-01

    Background Vibrio parahaemolyticus is abundant in the aquatic environment particularly in warmer waters and is the leading cause of seafood borne gastroenteritis worldwide. Prior to 1995, numerous V. parahaemolyticus serogroups were associated with disease, however, in that year an O3:K6 serogroup emerged in Southeast Asia causing large outbreaks and rapid hospitalizations. This new highly virulent strain is now globally disseminated. Results We performed a four-way BLAST analysis on the genome sequence of V. parahaemolyticus RIMD2210633, an O3:K6 isolate from Japan recovered in 1996, versus the genomes of four published Vibrio species and constructed genome BLAST atlases. We identified 24 regions, gaps in the genome atlas, of greater than 10 kb that were unique to RIMD2210633. These 24 regions included an integron, f237 phage, 2 type III secretion systems (T3SS), a type VI secretion system (T6SS) and 7 Vibrio parahaemolyticus genomic islands (VPaI-1 to VPaI-7). Comparative genomic analysis of our fifth genome, V. parahaemolyticus AQ3810, an O3:K6 isolate recovered in 1983, identified four regions unique to each V. parahaemolyticus strain. Interestingly, AQ3810 did not encode 8 of the 24 regions unique to RMID, including a T6SS, which suggests an additional virulence mechanism in RIMD2210633. The distribution of only the VPaI regions was highly variable among a collection of 42 isolates and phylogenetic analysis of these isolates show that these regions are confined to a pathogenic clade. Conclusion Our data show that there is considerable genomic flux in this species and that the new highly virulent clone arose from an O3:K6 isolate that acquired at least seven novel regions, which included both a T3SS and a T6SS. PMID:18590559

  5. Evaluation of bactericidal activity of weakly acidic electrolyzed water (WAEW) against Vibrio vulnificus and Vibrio parahaemolyticus.

    PubMed

    Quan, Yaru; Choi, Kyoo-Duck; Chung, Donghwa; Shin, Il-Shik

    2010-01-01

    Vibrio parahaemolyticus and Vibriovulnificus cause severe foodborne illness in humans; thus, to reduce outbreaks of disease, it is clearly important to reduce food contamination by these pathogens. Although electrolyzed oxidizing (EO) water has been reported to exhibit strong bactericidal activities against many pathogens, it has never been tested against V. vulnificus and V. parahaemolyticus. The purpose of this study was to evaluate the bactericidal activity of weakly acidic electrolyzed water (WAEW), a type of EO water, against V. vulnificus and V. parahaemolyticus. Cell suspensions and cell cultures of both pathogens were treated for 30s with sodium hypochlorite solution containing 35mg/L available chlorine concentration (ACC) or WAEW containing 35mg/L ACC. After an initial inoculum of 5.7logCFU/mL, the number of viable V. vulnificus cells was reduced by 2.2 logs after treatment for 60s with sodium hypochlorite solution containing 35mg/L ACC, while no cells survived treatment with WAEW for 30s. Similar results were obtained for V. parahaemolyticus. Under open storage conditions, WAEW maintained bactericidal activities against cell suspensions of both strains after 5weeks but disappeared against cell cultures of the two strains after 5weeks. Under closed storage conditions, however, WAEW maintained bactericidal activities against both cell suspensions and cell cultures of each strain after 5weeks. No cells were detected in the cell suspensions and cultures when the ACC of WAEW was more than 20mg/L and treatment time was greater than 15s. Bactericidal activity of WAEW against V. vulnificus cell culture was reduced when the ACC of WAEW was less than 15mg/L but was maintained in the V. vulnificus cell suspension when the ACC of WAEW was 0.5mg/L. Thus, the bactericidal activity of WAEW was primarily affected by ACC rather than treatment time. Similar results were obtained for V. parahaemolyticus, indicating that WAEW kills these microorganisms more quickly than a chemical product such as sodium hypochlorite (NaClO), even at equivalent ACCs. PMID:20004034

  6. Persistence, seasonal dynamics and pathogenic potential of Vibrio communities from Pacific oyster hemolymph.

    PubMed

    Wendling, Carolin C; Batista, Frederico M; Wegner, K Mathias

    2014-01-01

    Bacteria of the genus Vibrio occur at a continuum from free-living to symbiotic life forms, including opportunists and pathogens, that can contribute to severe diseases, for instance summer mortality events of Pacific oysters Crassostrea gigas. While most studies focused on Vibrio isolated from moribund oysters during mortality outbreaks, investigations of the Vibrio community in healthy oysters are rare. Therefore, we characterized the persistence, diversity, seasonal dynamics, and pathogenicity of the Vibrio community isolated from healthy Pacific oysters. In a reciprocal transplant experiment we repeatedly sampled hemolymph from adult Pacific oysters to differentiate population from site-specific effects during six months of in situ incubation in the field. We characterized virulence phenotypes and genomic diversity based on multilocus sequence typing in a total of 70 Vibrio strains. Based on controlled infection experiments we could show that strains with the ability to colonize healthy adult oysters can also have the potential to induce high mortality rates on larvae. Diversity and abundance of Vibrio varied significantly over time with highest values during and after spawning season. Vibrio communities from transplanted and stationary oysters converged over time, indicating that communities were not population specific, but rather assemble from the surrounding environment forming communities, some of which can persist over longer periods. PMID:24728233

  7. New insights into Oculina patagonica coral diseases and their associated Vibrio spp. communities.

    PubMed

    Rubio-Portillo, Esther; Yarza, Pablo; Peñalver, Cindy; Ramos-Esplá, Alfonso A; Antón, Josefa

    2014-09-01

    Bleaching of Oculina patagonica has been extensively studied in the Eastern Mediterranean Sea, although no studies have been carried out in the Western basin. In 1996 Vibrio mediterranei was reported as the causative agent of bleaching in O. patagonica but it has not been related to bleached or healthy corals since 2003, suggesting that it was no longer involved in bleaching of O. patagonica. In an attempt to clarify the relationship between Vibrio spp., seawater temperature and coral diseases, as well as to investigate the putative differences between Eastern and Western Mediterranean basins, we have analysed the seasonal patterns of the culturable Vibrio spp. assemblages associated with healthy and diseased O. patagonica colonies. Two sampling points located in the Spanish Mediterranean coast were chosen for this study: Alicante Harbour and the Marine Reserve of Tabarca. A complex and dynamic assemblage of Vibrio spp. was present in O. patagonica along the whole year and under different environmental conditions and coral health status. While some Vibrio spp. were detected all year around in corals, the known pathogens V. mediteranei and V. coralliilyticus were only present in diseased specimens. The pathogenic potential of these bacteria was studied by experimental infection under laboratory conditions. Both vibrios caused diseased signs from 24?°C, being higher and faster at 28?°C. Unexpectedly, the co-inoculation of these two Vibrio species seemed to have a synergistic pathogenic effect over O. patagonica, as disease signs were readily observed at temperatures at which bleaching is not normally observed. PMID:24621525

  8. Persistence, Seasonal Dynamics and Pathogenic Potential of Vibrio Communities from Pacific Oyster Hemolymph

    PubMed Central

    Wendling, Carolin C.; Batista, Frederico M.; Wegner, K. Mathias

    2014-01-01

    Bacteria of the genus Vibrio occur at a continuum from free-living to symbiotic life forms, including opportunists and pathogens, that can contribute to severe diseases, for instance summer mortality events of Pacific oysters Crassostrea gigas. While most studies focused on Vibrio isolated from moribund oysters during mortality outbreaks, investigations of the Vibrio community in healthy oysters are rare. Therefore, we characterized the persistence, diversity, seasonal dynamics, and pathogenicity of the Vibrio community isolated from healthy Pacific oysters. In a reciprocal transplant experiment we repeatedly sampled hemolymph from adult Pacific oysters to differentiate population from site-specific effects during six months of in situ incubation in the field. We characterized virulence phenotypes and genomic diversity based on multilocus sequence typing in a total of 70 Vibrio strains. Based on controlled infection experiments we could show that strains with the ability to colonize healthy adult oysters can also have the potential to induce high mortality rates on larvae. Diversity and abundance of Vibrio varied significantly over time with highest values during and after spawning season. Vibrio communities from transplanted and stationary oysters converged over time, indicating that communities were not population specific, but rather assemble from the surrounding environment forming communities, some of which can persist over longer periods. PMID:24728233

  9. Mannose-containing oligosaccharides of non-specific human secretory immunoglobulin A mediate inhibition of Vibrio cholerae biofilm formation.

    PubMed

    Murthy, Ashlesh K; Chaganty, Bharat K R; Troutman, Ty; Guentzel, M Neal; Yu, Jieh-Juen; Ali, Syed Khalid; Lauriano, Crystal M; Chambers, James P; Klose, Karl E; Arulanandam, Bernard P

    2011-01-01

    The role of antigen-specific secretory IgA (SIgA) has been studied extensively, whereas there is a limited body of evidence regarding the contribution of non-specific SIgA to innate immune defenses against invading pathogens. In this study, we evaluated the effects of non-specific SIgA against infection with Vibrio cholerae O139 strain MO10 and biofilm formation. Seven day old infant mice deficient in IgA (IgA(-/-) mice) displayed significantly greater intestinal MO10 burden at 24 hr post-challenge when compared to IgA(+/+) pups. Importantly, cross-fostering of IgA(-/-) pups with IgA(+/+) nursing dams reversed the greater susceptibility to MO10 infection, suggesting a role for non-specific SIgA in protection against the infection. Since biofilm formation is associated with virulence of MO10, we further examined the role of human non-specific SIgA on this virulence phenotype of the pathogen. Human non-specific SIgA, in a dose-dependent fashion, significantly reduced the biofilm formation by MO10 without affecting the viability of the bacterium. Such an inhibitory effect was not induced by human serum IgA, IgG, or IgM, suggesting a role for the oligosaccharide-rich secretory component (SC) of SIgA. This was supported by the demonstration that SIgA treated with endoglycosidase H, to cleave the high-mannose containing terminal chitobiose residues, did not induce a reduction in biofilm formation by MO10. Furthermore, the addition of free mannose per se, across a wide dose range, induced significant reduction in MO10 biofilm formation. Collectively, these results suggest that mannose containing oligosaccharides within human non-specific secretory IgA can alter important virulence phenotypes of Vibrio cholerae such as biofilm formation, without affecting viability of the microorganism. Such effects may contribute significantly to innate immune defenses against invading pathogens in vivo in the gastrointestinal tract. PMID:21347387

  10. Cholera outbreaks (2012) in three districts of Nepal reveal clonal transmission of multi-drug resistant Vibrio cholerae O1

    PubMed Central

    2014-01-01

    Background Although endemic cholera causes significant morbidity and mortality each year in Nepal, lack of information about the causal bacterium often hinders cholera intervention and prevention. In 2012, diarrheal outbreaks affected three districts of Nepal with confirmed cases of mortality. This study was designed to understand the drug response patterns, source, and transmission of Vibrio cholerae associated with 2012 cholera outbreaks in Nepal. Methods V. cholerae (n?=?28) isolated from 2012 diarrhea outbreaks {n?=?22; Kathmandu (n?=?12), Doti (n?=?9), Bajhang (n?=?1)}, and surface water (n?=?6; Kathmandu) were tested for antimicrobial response. Virulence properties and DNA fingerprinting of the strains were determined by multi-locus genetic screening employing polymerase chain reaction, DNA sequencing, and pulsed-field gel electrophoresis (PFGE). Results All V. cholerae strains isolated from patients and surface water were confirmed to be toxigenic, belonging to serogroup O1, Ogawa serotype, biotype El Tor, and possessed classical biotype cholera toxin (CTX). Double-mismatch amplification mutation assay (DMAMA)-PCR revealed the V. cholerae strains to possess the B-7 allele of ctx subunit B. DNA sequencing of tcpA revealed a point mutation at amino acid position 64 (N???S) while the ctxAB promoter revealed four copies of the tandem heptamer repeat sequence 5'-TTTTGAT-3'. V. cholerae possessed all the ORFs of the Vibrio seventh pandemic island (VSP)-I but lacked the ORFs 498–511 of VSP-II. All strains were multidrug resistant with resistance to trimethoprim-sulfamethoxazole (SXT), nalidixic acid (NA), and streptomycin (S); all carried the SXT genetic element. DNA sequencing and deduced amino acid sequence of gyrA and parC of the NAR strains (n?=?4) revealed point mutations at amino acid positions 83 (S???I), and 85 (S???L), respectively. Similar PFGE (NotI) pattern revealed the Nepalese V. cholerae to be clonal, and related closely with V. cholerae associated with cholera in Bangladesh and Haiti. Conclusions In 2012, diarrhea outbreaks in three districts of Nepal were due to transmission of multidrug resistant V. cholerae El Tor possessing cholera toxin (ctx) B-7 allele, which is clonal and related closely with V. cholerae associated with cholera in Bangladesh and Haiti. PMID:25022982

  11. Electron Micrograph of the Meat Spoilage Bacterium Lactobacillus sake

    NSDL National Science Digital Library

    American Society For Microbiology

    2003-09-22

    This image is of the meat spoilage bacterium Lactobacillus sake. This strain was originally isolated from a vacuum-packaged meat product. To enhance its aesthetic appeal, the original black and white image was colored using Adobe Photoshop.

  12. Characterizations of intracellular arsenic in a bacterium

    NASA Astrophysics Data System (ADS)

    Wolfe-Simon, F.; Yannone, S. M.; Tainer, J. A.

    2011-12-01

    Life requires a key set of chemical elements to sustain growth. Yet, a growing body of literature suggests that microbes can alter their nutritional requirements based on the availability of these chemical elements. Under limiting conditions for one element microbes have been shown to utilize a variety of other elements to serve similar functions often (but not always) in similar molecular structures. Well-characterized elemental exchanges include manganese for iron, tungsten for molybdenum and sulfur for phosphorus or oxygen. These exchanges can be found in a wide variety of biomolecules ranging from protein to lipids and DNA. Recent evidence suggested that arsenic, as arsenate or As(V), was taken up and incorporated into the cellular material of the bacterium GFAJ-1. The evidence was interpreted to support As(V) acting in an analogous role to phosphate. We will therefore discuss our ongoing efforts to characterize intracellular arsenate and how it may partition among the cellular fractions of the microbial isolate GFAJ-1 when exposed to As(V) in the presence of various levels of phosphate. Under high As(V) conditions, cells express a dramatically different proteome than when grown given only phosphate. Ongoing studies on the diversity and potential role of proteins and metabolites produced in the presence of As(V) will be reported. These investigations promise to inform the role and additional metabolic potential for As in biology. Arsenic assimilation into biomolecules contributes to the expanding set of chemical elements utilized by microbes in unusual environmental niches.

  13. [Metabolism of the thermophilic bacterium Oceanithermus profundus].

    PubMed

    Fedosov, D V; Podkopaeva, D A; Miroshnichenko, M L; Bonch-Osmolovskaia, E A; Lebedinski?, A V; Grabovich, M Iu

    2008-01-01

    The metabolism of the novel facultatively anaerobic thermophilic bacterium Oceanithermus profundus was studied during growth on maltose, acetate, pyruvate, and hydrogen. The utilization of carbohydrates was shown to proceed via the glycolytic pathway. Under microaerobic growth conditions, the metabolism of O. profundus grown on maltose depended on the substrate concentration. At an initial maltose concentration of 1.4 mM, O. profundus carried out oxygen respiration, and in the presence of 3.5 mM maltose, facilitated fermentation occurred, with the formation of acetate and ethanol and limited involvement of oxygen. The use of pyruvate and acetate occurs via the TCA cycle. In cells grown on acetate, the activity of glyoxylate pathway enzymes was revealed. Depending on the energy-yielding process providing for growth (oxygen respiration or nitrate reduction), cells contained cytochromes a and c or b, respectively. The results obtained demonstrate the plasticity of the metabolism of O. profundus, which thus appears to be well-adjusted to the rapidly changing conditions in deep-sea hydrothermal vents. PMID:18522319

  14. Isolation of Vibrio alginolyticus and Vibrio splendidus from Aquacultured Carpet Shell Clam (Ruditapes decussatus) Larvae Associated with Mass Mortalities

    PubMed Central

    Gómez-León, J.; Villamil, L.; Lemos, M. L.; Novoa, B.; Figueras, A.

    2005-01-01

    Two episodes of mortality of cultured carpet shell clams (Ruditapes decussatus) associated with bacterial infections were recorded during 2001 and 2002 in a commercial hatchery located in Spain. Vibrio alginolyticus was isolated as the primary organism from moribund clam larvae that were obtained during the two separate events. Vibrio splendidus biovar II, in addition to V. alginolyticus, was isolated as a result of a mixed Vibrio infection from moribund clam larvae obtained from the second mortality event. The larval mortality rates for these events were 62 and 73%, respectively. Mortality was also detected in spat. To our knowledge, this is the fist time that these bacterial species have been associated with larval and juvenile carpet shell clam mortality. The bacterial strains were identified by morphological and biochemical techniques and also by PCR and sequencing of a conserved region of the 16S rRNA gene. In both cases bacteria isolated in pure culture were inoculated into spat of carpet shell clams by intravalvar injection and by immersion. The mortality was attributed to the inoculated strains, since the bacteria were obtained in pure culture from the soft tissues of experimentally infected clams. V. alginolyticus TA15 and V. splendidus biovar II strain TA2 caused similar histological lesions that affected mainly the mantle, the velum, and the connective tissue of infected organisms. The general enzymatic activity of both live cells and extracellular products (ECPs), as evaluated by the API ZYM system, revealed that whole bacterial cells showed greater enzymatic activity than ECPs and that the activity of most enzymes ceased after heat treatment (100°C for 10 min). Both strain TA15 and strain TA2 produced hydroxamate siderophores, although the activity was greater in strain TA15. ECPs from both bacterial species at high concentrations, as well as viable bacteria, caused significant reductions in hemocyte survival after 4 h of incubation, whereas no significant differences in viability were observed during incubation with heat-killed bacteria. PMID:15640176

  15. Metabolism of Mandelate and Related Compounds by Bacterium ncib 8250

    Microsoft Academic Search

    S. I. T. Kennedy; C. A. Fewson

    1968-01-01

    SUMMARY Bacterium NCIB 8250 was grown on mandelate, benzyl alcohol, benzoyl- formate, benzaldehyde or benzoate and also on 2-hydroxy, 4-hydroxy, 3,4- dihydroxy and 4-hydroxy-3-methoxy derivatives of these compounds. Growth rates and yields of organism were measured for many of the sub- strates. The pathways of oxidation of mandelate and related compounds were investigated by the technique of simultaneous adaptation. Bacterium

  16. [Long-term survival of E1 Tor cholera vibrios in naturally contaminated sewage].

    PubMed

    Za?denov, A M; Saiamov, R M; Maloletkov, I S; Lazorenko, N F; Bichul', K G

    1976-01-01

    El Tor cholera vibrios of Ogava serological type were revealed in the sewage of the locomotive shed for 15 months. In experiment with an oil catcher in naturally infected sewage El Tor vibrios survived 36 days, in storage of this sewage at the laboratory--39 days, in the artificially infected sewage of a settlement and of a milk plant--2 and 11 days, respectively, in the oil and disel fuel--14 months. Consequently, El Tor vibrio can survive in the sewage with a high oil product content for a long time. PMID:1024446

  17. Comparative genomic analysis reveals evidence of two novel Vibrio species closely related to V. cholerae

    PubMed Central

    2010-01-01

    Background In recent years genome sequencing has been used to characterize new bacterial species, a method of analysis available as a result of improved methodology and reduced cost. Included in a constantly expanding list of Vibrio species are several that have been reclassified as novel members of the Vibrionaceae. The description of two putative new Vibrio species, Vibrio sp. RC341 and Vibrio sp. RC586 for which we propose the names V. metecus and V. parilis, respectively, previously characterized as non-toxigenic environmental variants of V. cholerae is presented in this study. Results Based on results of whole-genome average nucleotide identity (ANI), average amino acid identity (AAI), rpoB similarity, MLSA, and phylogenetic analysis, the new species are concluded to be phylogenetically closely related to V. cholerae and V. mimicus. Vibrio sp. RC341 and Vibrio sp. RC586 demonstrate features characteristic of V. cholerae and V. mimicus, respectively, on differential and selective media, but their genomes show a 12 to 15% divergence (88 to 85% ANI and 92 to 91% AAI) compared to the sequences of V. cholerae and V. mimicus genomes (ANI <95% and AAI <96% indicative of separate species). Vibrio sp. RC341 and Vibrio sp. RC586 share 2104 ORFs (59%) and 2058 ORFs (56%) with the published core genome of V. cholerae and 2956 (82%) and 3048 ORFs (84%) with V. mimicus MB-451, respectively. The novel species share 2926 ORFs with each other (81% Vibrio sp. RC341 and 81% Vibrio sp. RC586). Virulence-associated factors and genomic islands of V. cholerae and V. mimicus, including VSP-I and II, were found in these environmental Vibrio spp. Conclusions Results of this analysis demonstrate these two environmental vibrios, previously characterized as variant V. cholerae strains, are new species which have evolved from ancestral lineages of the V. cholerae and V. mimicus clade. The presence of conserved integration loci for genomic islands as well as evidence of horizontal gene transfer between these two new species, V. cholerae, and V. mimicus suggests genomic islands and virulence factors are transferred between these species. PMID:20507608

  18. Influence of Alginate on Attachment of Vibrio spp. to Stainless Steel Surfaces in Seawater

    PubMed Central

    Gordon, Andrew S.

    1987-01-01

    The influence of alginate on the attachment of Vibrio alginolyticus and Vibrio pelagius biovar II to stainless steel was investigated. When the bacteria were in stationary phase, alginate decreased the number of attached bacteria in the case of each Vibrio sp. In contrast, when V. pelagius biovar II was grown on alginate and harvested in log phase, attachment was increased. This effect may be due to nutrient availability at the surface or to receptors on the bacterial surface which interact with alginate adsorbed to the metal. PMID:16347345

  19. Detection and quantification of Vibrio populations using denaturant gradient gel electrophoresis.

    PubMed

    Eiler, Alexander; Bertilsson, Stefan

    2006-11-01

    Bacteria affiliated with the genus Vibrio are endemic in marine and estuarine ecosystems and are also found in many freshwater environments. Vibrios can enter viable but non-culturable states and since many species are pathogenic, there is a great need for culture-independent methods that identify and quantify multiple Vibrio populations. We adopted Vibrio-specific 16S rRNA-directed primers and a competitive PCR protocol (QC-PCR; [Thompson, J.R., Randa, M.A., Marcelino, L.A., Tomita-Mitchell, A., Lim, E., Polz, M.F., 2004b. Diversity and dynamics of a North Atlantic coastal Vibrio community. Appl. Environ. Microbiol. 70, 4103-4110]) for separation and quantification of Vibrio populations using denaturant gradient gel electrophoresis (DGGE). Sixteen Vibrio isolates and eight environmental samples were used to assess the precision and resolution of the method. A 45-70% gradient of Urea and formamide enabled separation of Vibrio populations with single nucleotide differences in the amplified fragment. A titration curve for the QC-PCR-DGGE, verified by amending surface water bacterioplankton samples with up to 3 x 10(5)Vibrio cholerae cells, could be approximated by a linear regression of log-transformed values (R(2)=0.96). The limit of detection for single populations was 180 cells per extracted sample or about 4 cells per PCR reaction. Environmental samples from the southern Stockholm archipelago in the Baltic Sea and the more saline coastal waters of Skagerrak each carried between 2 and 6 Vibrio populations, and there were major differences between the locations. Notably, multiple Vibrio populations could be detected and quantified against a background of native bacterioplankton exceeding Vibrio population abundance by more than 6 orders of magnitude. Putative identification based on migration in the DGGE gel was verified by parallel cloning and sequencing of PCR products, and representative clones were also characterized by DGGE. This general approach could also be useful for targeting other phylogenetically constrained bacterial groups and assess their abundance and distribution in complex environmental settings. PMID:16730823

  20. Antimicrobial Susceptibility of Vibrio vulnificus and Vibrio parahaemolyticus Recovered from Recreational and Commercial Areas of Chesapeake Bay and Maryland Coastal Bays

    PubMed Central

    Shaw, Kristi S.; Rosenberg Goldstein, Rachel E.; He, Xin; Jacobs, John M.; Crump, Byron C.; Sapkota, Amy R.

    2014-01-01

    Vibrio vulnificus and V. parahaemolyticus in the estuarine-marine environment are of human health significance and may be increasing in pathogenicity and abundance. Vibrio illness originating from dermal contact with Vibrio laden waters or through ingestion of seafood originating from such waters can cause deleterious health effects, particularly if the strains involved are resistant to clinically important antibiotics. The purpose of this study was to evaluate antimicrobial susceptibility among these pathogens. Surface-water samples were collected from three sites of recreational and commercial importance from July to September 2009. Samples were plated onto species-specific media and resulting V. vulnificus and V. parahaemolyticus strains were confirmed using polymerase chain reaction assays and tested for antimicrobial susceptibility using the Sensititre® microbroth dilution system. Descriptive statistics, Friedman two-way Analysis of Variance (ANOVA) and Kruskal-Wallis one-way ANOVA were used to analyze the data. Vibrio vulnificus (n?=?120) and V. parahaemolyticus (n?=?77) were isolated from all sampling sites. Most isolates were susceptible to antibiotics recommended for treating Vibrio infections, although the majority of isolates expressed intermediate resistance to chloramphenicol (78% of V. vulnificus, 96% of V. parahaemolyticus). Vibrio parahaemolyticus also demonstrated resistance to penicillin (68%). Sampling location or month did not significantly impact V. parahaemolyticus resistance patterns, but V. vulnificus isolates from St. Martin's River had lower overall intermediate resistance than that of the other two sampling sites during the month of July (p?=?0.0166). Antibiotics recommended to treat adult Vibrio infections were effective in suppressing bacterial growth, while some antibiotics recommended for pediatric treatment were not effective against some of the recovered isolates. To our knowledge, these are the first antimicrobial susceptibility data of V. vulnificus and V. parahaemolyticus recovered from the Chesapeake Bay. These data can serve as a baseline against which future studies can be compared to evaluate whether susceptibilities change over time. PMID:24586914

  1. Taxonomic characterization of the cellulose-degrading bacterium NCIB 10462

    SciTech Connect

    Dees, C.; Ringleberg, D.; Scott, T.C. [Oak Ridge National Lab., TN (United States); Phelps, T. [Univ. of Tennessee, Knoxville, TN (United States)

    1994-06-01

    The gram negative cellulase-producing bacterium NCIB 10462 has been previously named Pseudomonas fluorescens subsp. or var. cellulosa. Since there is renewed interest in cellulose-degrading bacteria for use in bioconversion of cellulose to chemical feed stocks and fuels, we re-examined the characteristics of this microorganism to determine its proper taxonomic characterization and to further define it`s true metabolic potential. Metabolic and physical characterization of NCIB 10462 revealed that this was an alkalophilic, non-fermentative, gram negative, oxidase positive, motile, cellulose-degrading bacterium. The aerobic substrate utilization profile of this bacterium was found to have few characteristics consistent with a classification of P. fluorescens with a very low probability match with the genus Sphingomonas. Total lipid analysis did not reveal that any sphingolipid bases are produced by this bacterium. NCIB 10462 was found to grow best aerobically but also grows well in complex media under reducing conditions. NCIB 10462 grew slowly under full anaerobic conditions on complex media but growth on cellulosic media was found only under aerobic conditions. Total fatty acid analysis (MIDI) of NCIB 10462 failed to group this bacterium with a known pseudomonas species. However, fatty acid analysis of the bacteria when grown at temperatures below 37{degrees}C suggest that the organism is a pseudomonad. Since a predominant characteristic of this bacterium is it`s ability to degrade cellulose, we suggest it be called Pseudomonas cellulosa.

  2. Characterization of the cellulose-degrading bacterium NCIMB 10462

    SciTech Connect

    Dees, C.; Scott, T.C.; Phelps, T.J. [Oak Ridge National Lab, TN (United States)] [and others

    1995-12-31

    The gram-negative cellulase-producing bacterium NCIMB 10462 has been previously named Pseudomonas fluorescens subsp. or var. cellulose. Because of renewed interest in cellulose-degrading bacteria for use in the bioconversion of cellulose to chemical feed stocks and fuels, we re-examined the characteristics of this microorganism to determine its true metabolic potential. Metabolic and physical characterization of NCIMB 10462 revealed that this is an alkalophilic, non-fermentative, gram-negative, oxidase-positive, motile, cellulose-degrading bacterium. The aerobic substrate utilization profile of this bacterium has few characteristics consistent with a classification of P. fluorescens and a very low probability match with the genus Sphingomonas. However, total lipid analysis did not reveal that any sphingolipid bases are produced by this bacterium. NCIMB 10462 grows best aerobically, but also grows well in complex media under reducing conditions. NCIMB 10462 grows slowly under anaerobic conditions on complex media, but growth on cellulosic media occurred only under aerobic conditions. Total fatty acid analysis (MIDI) of NCIMB 10462 failed to group this bacterium with a known pseudomonas species. However, fatty acid analysis of the bacteria when grown at temperatures below 37{degrees}C suggest that the organism is a pseudomonad. Since a predominant characteristic of this bacterium is its ability to degrade cellulose, we suggest that it be called Pseudomonas cellulosa.

  3. LitR Is a Repressor of syp Genes and Has a Temperature-Sensitive Regulatory Effect on Biofilm Formation and Colony Morphology in Vibrio (Aliivibrio) salmonicida

    PubMed Central

    Bjelland, Ane Mohn; Ronessen, Maria; Robertsen, Espen; Willassen, Nils Peder

    2014-01-01

    Vibrio (Aliivibrio) salmonicida is the etiological agent of cold water vibriosis, a disease in farmed Atlantic salmon (Salmo salar) that is kept under control due to an effective vaccine. A seawater temperature below 12°C is normally required for disease development. Quorum sensing (QS) is a cell density-regulated communication system that bacteria use to coordinate activities involved in colonization and pathogenesis, and we have previously shown that inactivation of the QS master regulator LitR attenuates the V. salmonicida strain LFI1238 in a fish model. We show here that strain LFI1238 and a panel of naturally occurring V. salmonicida strains are poor biofilm producers. Inactivation of litR in the LFI1238 strain enhances medium- and temperature-dependent adhesion, rugose colony morphology, and biofilm formation. Chemical treatment and electron microscopy of the biofilm identified an extracellular matrix consisting mainly of a fibrous network, proteins, and polysaccharides. Further, by microarray analysis of planktonic and biofilm cells, we identified a number of genes regulated by LitR and, among these, were homologues of the Vibrio fischeri symbiosis polysaccharide (syp) genes. The syp genes were regulated by LitR in both planktonic and biofilm lifestyle analyses. Disruption of syp genes in the V. salmonicida ?litR mutant alleviated adhesion, rugose colony morphology, and biofilm formation. Hence, LitR is a repressor of syp transcription that is necessary for expression of the phenotypes examined. The regulatory effect of LitR on colony morphology and biofilm formation is temperature sensitive and weak or absent at temperatures above the bacterium's upper threshold for pathogenicity. PMID:24973072

  4. Molecular characterization of a glutathione peroxidase gene and its expression in the selected Vibrio-resistant population of the clam Meretrix meretrix.

    PubMed

    Wang, Chao; Huan, Pin; Yue, Xin; Yan, Maocang; Liu, Baozhong

    2011-06-01

    Glutathione peroxidase (GPx) is an important member of cellular enzymatic antioxidant system, which may be involved in pathogen defense of host. In the present study, a selenium-dependent glutathione peroxidase (MmeGPx) gene from clam Meretrix meretrix was cloned and analyzed. The MmeGPx gene was composed of two introns of 723 bp and 238 bp and an open reading frame (ORF) of 711 bp. The ORF encodes a protein of 237 amino acids with a putative selenocysteine residue encoded by an unusual stop codon. MmeGPx shares a higher level of similarity with human GPx 3 than with other human GPx isozymes. The level of MmeGPx mRNA roughly paralleled GPx enzyme activity in different tissues except in gills, with the highest mRNA expression and enzyme activity occurring in hepatopancreas. MmeGPx mRNA expressions were detected in different larval stages and the results showed that MmeGPx mRNA increased significantly in pediveliger stage, which may be a response to oxidative stress. After challenge of clam with a Vibrio parahaemolyticus-related bacterium (MM21), the expression of MmeGPx was significantly up-regulated at 6 h and 12 h in hepatopancreas, which suggested that MmeGPx may be involved in the immune response to MM21 infection. To better understand its role in the immunity of clam, the expression of MmeGPx in hepatopancreas was compared between a selected Vibrio-resistant population and a control population after immersion challenge with MM21. Early up-regulation of MmeGPx was observed in the resistant population. These results suggested that MmeGPx might be involved in maintaining the redox state of immune system, and the early immune response to pathogen infection may help the clam against pathogen infection. PMID:21440068

  5. LitR is a repressor of syp genes and has a temperature-sensitive regulatory effect on biofilm formation and colony morphology in vibrio (Aliivibrio) salmonicida.

    PubMed

    Hansen, Hilde; Bjelland, Ane Mohn; Ronessen, Maria; Robertsen, Espen; Willassen, Nils Peder

    2014-09-01

    Vibrio (Aliivibrio) salmonicida is the etiological agent of cold water vibriosis, a disease in farmed Atlantic salmon (Salmo salar) that is kept under control due to an effective vaccine. A seawater temperature below 12°C is normally required for disease development. Quorum sensing (QS) is a cell density-regulated communication system that bacteria use to coordinate activities involved in colonization and pathogenesis, and we have previously shown that inactivation of the QS master regulator LitR attenuates the V. salmonicida strain LFI1238 in a fish model. We show here that strain LFI1238 and a panel of naturally occurring V. salmonicida strains are poor biofilm producers. Inactivation of litR in the LFI1238 strain enhances medium- and temperature-dependent adhesion, rugose colony morphology, and biofilm formation. Chemical treatment and electron microscopy of the biofilm identified an extracellular matrix consisting mainly of a fibrous network, proteins, and polysaccharides. Further, by microarray analysis of planktonic and biofilm cells, we identified a number of genes regulated by LitR and, among these, were homologues of the Vibrio fischeri symbiosis polysaccharide (syp) genes. The syp genes were regulated by LitR in both planktonic and biofilm lifestyle analyses. Disruption of syp genes in the V. salmonicida ?litR mutant alleviated adhesion, rugose colony morphology, and biofilm formation. Hence, LitR is a repressor of syp transcription that is necessary for expression of the phenotypes examined. The regulatory effect of LitR on colony morphology and biofilm formation is temperature sensitive and weak or absent at temperatures above the bacterium's upper threshold for pathogenicity. PMID:24973072

  6. Occurrence and Expression of Luminescence in Vibrio cholerae?

    PubMed Central

    Grim, Christopher J.; Taviani, Elisa; Alam, Munirul; Huq, Anwar; Sack, R. Bradley; Colwell, Rita R.

    2008-01-01

    Several species of the genus Vibrio, including Vibrio cholerae, are bioluminescent or contain bioluminescent strains. Previous studies have reported that only 10% of V. cholerae strains are luminescent. Analysis of 224 isolates of non-O1/non-O139 V. cholerae collected from Chesapeake Bay, MD, revealed that 52% (116/224) were luminescent when an improved assay method was employed and 58% (130/224) of isolates harbored the luxA gene. In contrast, 334 non-O1/non-O139 V. cholerae strains isolated from two rural provinces in Bangladesh yielded only 21 (6.3%) luminescent and 35 (10.5%) luxA+ isolates. An additional 270 clinical and environmental isolates of V. cholerae serogroups O1 and O139 were tested, and none were luminescent or harbored luxA. These results indicate that bioluminescence may be a trait specific for non-O1/non-O139 V. cholerae strains that frequently occur in certain environments. Luminescence expression patterns of V. cholerae were also investigated, and isolates could be grouped based on expression level. Several strains with defective expression of the lux operon, including natural K variants, were identified. PMID:18065611

  7. Vibrio cholerae Represses Polysaccharide Synthesis To Promote Motility in Mucosa.

    PubMed

    Liu, Zhenyu; Wang, Yuning; Liu, Shengyan; Sheng, Ying; Rueggeberg, Karl-Gustav; Wang, Hui; Li, Jie; Gu, Frank X; Zhong, Zengtao; Kan, Biao; Zhu, Jun

    2015-03-01

    The viscoelastic mucus layer of gastrointestinal tracts is a host defense barrier that a successful enteric pathogen, such as Vibrio cholerae, must circumvent. V. cholerae, the causative agent of cholera, is able to penetrate the mucosa and colonize the epithelial surface of the small intestine. In this study, we found that mucin, the major component of mucus, promoted V. cholerae movement on semisolid medium and in liquid medium. A genome-wide screen revealed that Vibrio polysaccharide (VPS) production was inversely correlated with mucin-enhanced motility. Mucin adhesion assays indicated that VPS bound to mucin. Moreover, we found that vps expression was reduced upon exposure to mucin. In an infant mouse colonization model, mutants that overexpressed VPS colonized less effectively than wild-type strains in more distal intestinal regions. These results suggest that V. cholerae is able to sense mucosal signals and modulate vps expression accordingly so as to promote fast motion in mucus, thus allowing for rapid spread throughout the intestines. PMID:25561707

  8. Invariant recognition of polychromatic images of Vibrio cholerae 01

    NASA Astrophysics Data System (ADS)

    Alvarez-Borrego, Josue; Mourino-Perez, Rosa R.; Cristobal, Gabriel; Pech-Pacheco, Jose L.

    2002-04-01

    Cholera is an acute intestinal infectious disease. It has claimed many lives throughout history, and it continues to be a global health threat. Cholera is considered one of the most important emergence diseases due its relation with global climate changes. Automated methods such as optical systems represent a new trend to make more accurate measurements of the presence and quantity of this microorganism in its natural environment. Automatic systems eliminate observer bias and reduce the analysis time. We evaluate the utility of coherent optical systems with invariant correlation for the recognition of Vibrio cholerae O1. Images of scenes are recorded with a CCD camera and decomposed in three RGB channels. A numeric simulation is developed to identify the bacteria in the different samples through an invariant correlation technique. There is no variation when we repeat the correlation and the variation between images correlation is minimum. The position-, scale-, and rotation-invariant recognition is made with a scale transform through the Mellin transform. The algorithm to recognize Vibrio cholerae O1 is the presence of correlation peaks in the green channel output and their absence in red and blue channels. The discrimination criterion is the presence of correlation peaks in red, green, and blue channels.

  9. Extreme polyploidy in a large bacterium

    PubMed Central

    Mendell, Jennifer E.; Clements, Kendall D.; Choat, J. Howard; Angert, Esther R.

    2008-01-01

    Cells rely on diffusion to move metabolites and biomolecules. Diffusion is highly efficient but only over short distances. Although eukaryotic cells have broken free of diffusion-dictated constraints on cell size, most bacteria and archaea are forced to remain small. Exceptions to this rule are found among the bacterial symbionts of surgeonfish; Epulopiscium spp. are cigar-shaped cells that reach lengths in excess of 600 ?m. A large Epulopiscium contains thousands of times more DNA than a bacterium such as Escherichia coli, but the composition of this DNA is not well understood. Here, we present evidence that Epulopiscium contains tens of thousands of copies of its genome. Using quantitative, single-cell PCR assays targeting single-copy genes, we have determined that copy number is positively correlated with Epulopiscium cell size. Although other bacteria are known to possess multiple genomes, polyploidy of the magnitude observed in Epulopiscium is unprecedented. The arrangement of genomes around the cell periphery may permit regional responses to local stimuli, thus allowing Epulopiscium to maintain its unusually large size. Surveys of the sequences of single-copy genes (dnaA, recA, and ftsZ) revealed genetic homogeneity within a cell consistent with only a small amount (?1%) of the parental DNA being transferred to the next generation. The results also suggest that the abundance of genome copies in Epulopiscium may allow for an unstable genetic feature, a long mononucleotide tract, in an essential gene. With the evolution of extreme polyploidy and large cell size, Epulopiscium has acquired some of the advantages of eukaryotic cells. PMID:18445653

  10. RESPONSES OF OYSTER (CRASSOSTREA VIRGINICA) HEMOCYTES TO NONPATHOGENIC AND CLINICAL ISOLATES OF VIBRIO PARAHAEMOLYTICUS

    EPA Science Inventory

    Bacterial uptake by oysters (Crassostrea virginica) and bactericidal activity of oyster hemocytes were studied using four environmental isolates and three clinical isolates of Vibrio parahaemolyticus. Clinical isolates (2030, 2062, 2107) were obtained from gastroenteritis patien...

  11. Experimental Reservoirs of Human Pathogens: The Vibrio Cholerae Paradigm (7th Annual SFAF Meeting, 2012)

    ScienceCinema

    Colwell, Rita [University of Maryland

    2013-02-12

    Rita Colwell on "Experimental Reservoirs of Human Pathogens: The Vibrio cholerae paradigm" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.

  12. Constitutive Type VI Secretion System Expression Gives Vibrio cholerae Intra- and Interspecific Competitive Advantages

    E-print Network

    Unterweger, Daniel

    The type VI secretion system (T6SS) mediates protein translocation across the cell membrane of Gram-negative bacteria, including Vibrio cholerae – the causative agent of cholera. All V. cholerae strains examined to date ...

  13. INFLUENCE OF SEASONAL FACTORS ON OYSTER HEMOCYTE KILLING OF VIBRIO PARAHEMOLYTICUS

    EPA Science Inventory

    Seasonal variation of cellular defenses of oyster Crassostrea virginica against Vibrio parahaemolyticus were examined from June 1997 to December 1998 using a recently developed bactericidal assay that utilizes a tetrazolium dye. Mean hemocyte numbers, plasma lysozyme, and P. mari...

  14. Severe septic shock and cardiac arrest in a patient with Vibrio metschnikovii: a case report

    PubMed Central

    2014-01-01

    Introduction Vibrio metschnikovii is a very rare species and can be fatal to patients with massive comorbidity. Until now only eight other cases have been reported. Case presentation This case report describes a 78-year-old Danish man who presented with fever, hypotension and unconsciousness and he developed cardiac arrest. Vibrio metschnikovii was identified in all his blood samples and effective antibiotics were initiated. Conclusions The human sources are believed to include shrimps, birds, water, sewage and seafood. We report the first case of Vibrio metschnikovii from a Nordic country and the report shows that even though isolation of Vibrio metschnikovii from human clinical samples is very rare, it still infects humans and may be fatal, despite sufficient treatment. PMID:25331560

  15. Experimental Reservoirs of Human Pathogens: The Vibrio Cholerae Paradigm (7th Annual SFAF Meeting, 2012)

    SciTech Connect

    Colwell, Rita [University of Maryland] [University of Maryland

    2012-06-01

    Rita Colwell on "Experimental Reservoirs of Human Pathogens: The Vibrio cholerae paradigm" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.

  16. THE EVOLUTIONARY ECOLOGY OF A SEPIOLID SQUID-VIBRIO ASSOCIATION: FROM CELL TO ENVIRONMENT

    E-print Network

    McFall-Ngai, Margaret

    for understanding the role of symbiotic competence. Keywords VIBRIO; MUTUALISM; SEPIOLID; EVOLUTION INTRODUCTION All of the microbial partner(s) to remain in the association without being detected by the host's immune capabilities

  17. DIFFERENTIAL EFFECTS OF OYSTER (CRASSOSTREA VIRGINICA) DEFENSES ON CLINICAL AND ENVIRONMENTAL ISOLATES OF VIBRIO PARAHEMOLYTICUS

    EPA Science Inventory

    Three clinical (2030, 2062, and 2107) and three environmental (1094, 1163, and ATCC 17802) isolates of Vibrio parahaemolyticus were exposed to hemocytes and plasma collected from oysters (Crassostrea virginica) to determine their susceptibility to putative oyster defenses. Clinic...

  18. Polyphyly of non-bioluminescent Vibrio fischeri sharing a lux-locus deletion

    E-print Network

    Wollenberg, M. S.

    This study reports the first description and molecular characterization of naturally occurring, non-bioluminescent strains of Vibrio fischeri. These ‘dark’V. fischeri strains remained non-bioluminescent even after treatment ...

  19. The Association of Virulent Vibrio Spp. Bacteria on Gafftopsail and Hardhead Catfish in Galveston Bay

    E-print Network

    Gilbert, Leslie Deanne

    2011-10-21

    THE ASSOCIATION OF VIRULENT VIBRIO SPP. BACTERIA ON GAFFTOPSAIL AND HARDHEAD CATFISH IN GALVESTON BAY A Thesis by LESLIE DEANNE GILBERT Submitted to the Office of Graduate Studies of Texas A&M University in partial... Catfish in Galveston Bay Copyright 2010 Leslie Deanne Gilbert THE ASSOCIATION OF VIRULENT VIBRIO SPP. BACTERIA ON GAFFTOPSAIL AND HARDHEAD CATFISH IN GALVESTON BAY A Thesis by LESLIE DEANNE GILBERT Submitted to the Office of Graduate...

  20. Prodigiosin from Vibrio sp. DSM 14379; A New UV-Protective Pigment

    Microsoft Academic Search

    Maja Bori?; Tjaša Danev?i?; David Stopar

    Pigments such as melanin, scytonemin and carotenoids protect microbial cells against the harmful effects of ultraviolet (UV)\\u000a radiation. The role in UV protection has never been assigned to the prodigiosin pigment. In this work, we demonstrate that\\u000a prodigiosin provides a significant level of protection against UV stress in Vibrio sp. DSM 14379. In the absence of pigment production, Vibrio sp.

  1. Ocean warming and spread of pathogenic vibrios in the aquatic environment.

    PubMed

    Vezzulli, Luigi; Colwell, Rita R; Pruzzo, Carla

    2013-05-01

    Vibrios are among the most common bacteria that inhabit surface waters throughout the world and are responsible for a number of severe infections both in humans and animals. Several reports recently showed that human Vibrio illnesses are increasing worldwide including fatal acute diarrheal diseases, such as cholera, gastroenteritis, wound infections, and septicemia. Many scientists believe this increase may be associated with global warming and rise in sea surface temperature (SST), although not enough evidence is available to support a causal link between emergence of Vibrio infections and climate warming. The effect of increased SST in promoting spread of vibrios in coastal and brackish waters is considered a causal factor explaining this trend. Field and laboratory studies carried out over the past 40 years supported this hypothesis, clearly showing temperature promotes Vibrio growth and persistence in the aquatic environment. Most recently, a long-term retrospective microbiological study carried out in the coastal waters of the southern North Sea provided the first experimental evidence for a positive and significant relationship between SST and Vibrio occurrence over a multidecadal time scale. As a future challenge, macroecological studies of the effects of ocean warming on Vibrio persistence and spread in the aquatic environment over large spatial and temporal scales would conclusively support evidence acquired to date combined with studies of the impact of global warming on epidemiologically relevant variables, such as host susceptibility and exposure. Assessing a causal link between ongoing climate change and enhanced growth and spread of vibrios and related illness is expected to improve forecast and mitigate future outbreaks associated with these pathogens. PMID:23280498

  2. Toxin producing Vibrio cholerae O75 outbreak, United States, March to April 2011.

    PubMed

    Onifade, T J M; Hutchinson, R; Van Zile, K; Bodager, D; Baker, R; Blackmore, C

    2011-01-01

    The Florida Department of Health, Florida, United States, is investigating a Vibrio cholerae O75 outbreak. Ten cases with disease onsets from 23 March to 13 April 2011, presented with gastrointestinal symptoms of diarrhoea, nausea, vomiting, cramps, chills, and/or fever, after consuming raw or lightly cooked oysters harvested from Apalachicola Bay, Florida. Symptoms were milder than those during outbreaks of epidemic (serogroup O1 and O139) Vibrio cholerae; no case required rehydration treatment or hospitalisation. PMID:21616048

  3. Complete Genome Sequence for the Shellfish Pathogen Vibrio coralliilyticus RE98 Isolated from a Shellfish Hatchery

    PubMed Central

    Bono, James L.; Watson, Michael A.; Needleman, David S.

    2014-01-01

    Vibrio coralliilyticus is a pathogen of corals and larval shellfish. Publications on strain RE98 list it as a Vibrio tubiashii; however, whole genome sequencing confirms RE98 as V. coralliilyticus containing a total of 6,037,824 bp consisting of two chromosomes (3,420,228 and 1,917,482 bp) and two megaplasmids (380,714 and 319,400 bp). PMID:25523764

  4. Production of the phytohormone indole-3-acetic acid by estuarine species of the genus Vibrio.

    PubMed

    Gutierrez, Casandra K; Matsui, George Y; Lincoln, David E; Lovell, Charles R

    2009-04-01

    Strains of Vibrio spp. isolated from roots of the estuarine grasses Spartina alterniflora and Juncus roemerianus produce the phytohormone indole-3-acetic acid (IAA). The colorimetric Salkowski assay was used for initial screening of IAA production. Gas chromatography-mass spectroscopy (GC-MS) was then employed to confirm and quantify IAA production. The accuracy of IAA quantification by the Salkowski assay was examined by comparison to GC-MS assay values. Indole-3-acetamide, an intermediate in IAA biosynthesis by the indole-3-acetamide pathway, was also identified by GC-MS. Multilocus sequence typing of concatenated 16S rRNA, recA, and rpoA genes was used for phylogenetic analysis of environmental isolates within the genus Vibrio. Eight Vibrio type strains and five additional species-level clades containing a total of 16 environmental isolates and representing five presumptive new species were identified as IAA-producing Vibrio species. Six additional environmental isolates similar to four of the Vibrio type strains were also IAA producers. To our knowledge, this is the first report of IAA production by species of the genus Vibrio or by bacteria isolated from an estuarine environment. PMID:19218411

  5. Antibacterial activity of Sonoran propolis and some of its constituents against clinically significant Vibrio species.

    PubMed

    Navarro-Navarro, Moises; Ruiz-Bustos, Patricia; Valencia, Dora; Robles-Zepeda, Ramón; Ruiz-Bustos, Eduardo; Virués, Claudia; Hernandez, Javier; Domínguez, Zaira; Velazquez, Carlos

    2013-02-01

    The aim of the present study was to evaluate the anti-Vibrio activity of propolis collected from three different areas of the Sonoran Desert in northwestern, Mexico [Pueblo de Alamos (PAP), Ures (UP), and Caborca (CP)]. The anti-Vibrio spp. activity of Sonoran propolis was determined by the broth microdilution method. UP propolis showed the highest antibacterial activity [minimal inhibitory concentration (MIC(50))<50 ?g mL(-1)] against Vibrio spp. (UP>CP>PAP). UP propolis significantly inhibited the growth of Vibrio cholerae O1 serotype Inaba (MIC(50)<50 ?g mL(-1)), V. cholerae non-O1 (MIC(50)<50 ?g mL(-1)), V. vulnificus (MIC(50)<50 ?g mL(-1)), and V. cholerae O1 serotype Ogawa (MIC(50) 100 ?g mL(-1)), in a concentration-dependent manner. The UP propolis constituents, galangin and caffeic acid phenethyl ester (CAPE), exhibited a potent growth inhibitory activity (MIC(50) 0.05-0.1 mmol l(-1)) against V. cholerae strains (non-O1 and serotype Ogawa). The strong anti-Vibrio activity of Sonoran propolis and some of its chemical constituents (galangin and CAPE) support further studies on the clinical applications of this natural bee product against different Vibrio spp., mainly V. cholerae. PMID:23351031

  6. First Characterization of Bacterial Pathogen, Vibrio alginolyticus, for Porites andrewsi White Syndrome in the South China Sea

    PubMed Central

    Chaoqun, Hu; Zhixiong, Zhu; Shifeng, Wang; Yongcan, Zhou

    2013-01-01

    Background White syndrome, a term for scleractinian coral disease with progressive tissue loss, is known to cause depressed growth and increased morality of coral reefs in the major oceans around the world, and the occurrence of this disease has been frequently reported in the past few decades. Investigations during April to September in both 2010 and 2011 identified widespread Poritesandrewsi White syndrome (PAWS) in Xisha Archipelago, South China Sea. However, the causes and etiology of PAWS have been unknown. Methodology/Principal Findings A transmission experiment was performed on P. andrewsi in the Qilianyu Subgroup (QLY). The results showed that there was a significant (P ? 0.05) difference between test and control groups after 28 days if the invalid replicates were excluded. Rates of tissue loss ranged from 0.90-10.76 cm2 d-1 with a mean of 5.40 ± 3.34 cm2 d-1 (mean ± SD). Bacterial strains were isolated from the PAWS corals at the disease outbreak sites in QLY of the Xisha Archipelago, South China Sea, and included in laboratory-based infection trials to satisfy Koch’s postulates for establishing causality. Following exposure to bacterial concentrations of 105 cells mL-1, the infected colonies exhibited similar signs to those observed in the field. Using phylogenetic 16S rRNA gene analysis, classical phenotypic trait comparison, Biolog automatic identification system, MALDI-TOF mass spectrometry and MALDI Biotyper method, two pathogenic strains were identified as Vibrioalginolyticus. Conclusion/Significance This is the first report of V. alginolyticus as a pathogenic agent of PAWS in the South China Sea. Our results point out an urgent need to develop sensitive detection methods for V. alginolyticus virulence strains and robust diagnostics for coral disease caused by this and Vibrio pathogenic bacterium in the South China Sea. PMID:24086529

  7. Comparative genomics reveals mechanism for short-term and long-term clonal transitions in pandemic Vibrio cholerae

    PubMed Central

    Chun, Jongsik; Grim, Christopher J.; Hasan, Nur A.; Lee, Je Hee; Choi, Seon Young; Haley, Bradd J.; Taviani, Elisa; Jeon, Yoon-Seong; Kim, Dong Wook; Lee, Jae-Hak; Brettin, Thomas S.; Bruce, David C.; Challacombe, Jean F.; Detter, J. Chris; Han, Cliff S.; Munk, A. Christine; Chertkov, Olga; Meincke, Linda; Saunders, Elizabeth; Walters, Ronald A.; Huq, Anwar; Nair, G. Balakrish; Colwell, Rita R.

    2009-01-01

    Vibrio cholerae, the causative agent of cholera, is a bacterium autochthonous to the aquatic environment, and a serious public health threat. V. cholerae serogroup O1 is responsible for the previous two cholera pandemics, in which classical and El Tor biotypes were dominant in the sixth and the current seventh pandemics, respectively. Cholera researchers continually face newly emerging and reemerging pathogenic clones carrying diverse combinations of phenotypic and genotypic properties, which significantly hampered control of the disease. To elucidate evolutionary mechanisms governing genetic diversity of pandemic V. cholerae, we compared the genome sequences of 23 V. cholerae strains isolated from a variety of sources over the past 98 years. The genome-based phylogeny revealed 12 distinct V. cholerae lineages, of which one comprises both O1 classical and El Tor biotypes. All seventh pandemic clones share nearly identical gene content. Using analogy to influenza virology, we define the transition from sixth to seventh pandemic strains as a “shift” between pathogenic clones belonging to the same O1 serogroup, but from significantly different phyletic lineages. In contrast, transition among clones during the present pandemic period is characterized as a “drift” between clones, differentiated mainly by varying composition of laterally transferred genomic islands, resulting in emergence of variants, exemplified by V. cholerae O139 and V. cholerae O1 El Tor hybrid clones. Based on the comparative genomics it is concluded that V. cholerae undergoes extensive genetic recombination via lateral gene transfer, and, therefore, genome assortment, not serogroup, should be used to define pathogenic V. cholerae clones. PMID:19720995

  8. Phaeobacter gallaeciensis Reduces Vibrio anguillarum in Cultures of Microalgae and Rotifers, and Prevents Vibriosis in Cod Larvae

    PubMed Central

    D’Alvise, Paul W.; Lillebø, Siril; Prol-Garcia, Maria J.; Wergeland, Heidrun I.; Nielsen, Kristian F.; Bergh, Øivind; Gram, Lone

    2012-01-01

    Phaeobacter gallaeciensis can antagonize fish-pathogenic bacteria in vitro, and the purpose of this study was to evaluate the organism as a probiont for marine fish larvae and their feed cultures. An in vivo mechanism of action of the antagonistic probiotic bacterium is suggested using a non-antagonistic mutant. P. gallaeciensis was readily established in axenic cultures of the two microalgae Tetraselmis suecica and Nannochloropsis oculata, and of the rotifer Brachionus plicatilis. P. gallaeciensis reached densities of 107 cfu/ml and did not adversely affect growth of algae or rotifers. Vibrio anguillarum was significantly reduced by wild-type P. gallaeciensis, when introduced into these cultures. A P. gallaeciensis mutant that did not produce the antibacterial compound tropodithietic acid (TDA) did not reduce V. anguillarum numbers, suggesting that production of the antibacterial compound is important for the antagonistic properties of P. gallaeciensis. The ability of P. gallaeciensis to protect fish larvae from vibriosis was determined in a bath challenge experiment using a multidish system with 1 larva per well. Unchallenged larvae reached 40% accumulated mortality which increased to 100% when infected with V. anguillarum. P. gallaeciensis reduced the mortality of challenged cod larvae (Gadus morhua) to 10%, significantly below the levels of both the challenged and the unchallenged larvae. The TDA mutant reduced mortality of the cod larvae in some of the replicates, although to a much lesser extent than the wild type. It is concluded that P. gallaeciensis is a promising probiont in marine larviculture and that TDA production likely contributes to its probiotic effect. PMID:22928051

  9. Snapshot of Vibrio parahaemolyticus densities in open and closed shellfish beds in Coastal South Carolina and Mississippi.

    PubMed

    Moore, J Gooch; Ruple, A; Ballenger-Bass, K; Bell, S; Pennington, P L; Scott, G I

    2014-11-01

    Vibrio parahaemolyticus is a Gram negative, halophilic bacterium that is ubiquitous in warm, tropical waters throughout the world. It is a major cause of seafood-associated gastroenteritis and is generally associated with consumption of raw or undercooked seafood, especially oysters. This study presents a snapshot of total V. parahaemolyticus densities in surface waters and shellstock American oysters (Crassostrea virginica) from open and closed shellfish harvesting areas, as well as "more rural areas" on two different US coasts, the Atlantic and the Gulf. Sampling was conducted from 2001 to 2003 at five sites near Charleston/Georgetown, SC and at four locations in the Gulfport/Pascagoula, MS area. V. parahaemolyticus numbers were determined by a direct plating method using an alkaline-phosphatase-labeled DNA probe targeting the species-specific thermolabile hemolysin gene (tlh) that was used for identification of bacterial isolates. The greatest difference between the two coasts was salinity; mean salinity in SC surface waters was 32.9 ppt, whereas the mean salinity in MS waters was 19.2 ppt, indicating more freshwater input into MS shellfish harvesting areas during the study period. The mean V. parahaemolyticus numbers in oysters were almost identical between the two states (567.4 vs. 560.1 CFU/g). Bacterial numbers in the majority of surface water samples from both states were at or below the limit of detection (LOD?=?<10 CFU/mL). The bacterial concentrations determined during this study predict a low public health risk from consumption of oysters in shellfish growing areas on either the Gulf or the Atlantic US coast. PMID:25106119

  10. Quorum sensing-dependent metalloprotease VvpE is important in the virulence of Vibrio vulnificus to invertebrates.

    PubMed

    Ha, Changwan; Kim, Soo-Kyoung; Lee, Mi-Nan; Lee, Joon-Hee

    2014-01-01

    Vibrio vulnificus, a Gram-negative bacterium, is an opportunistic human pathogen responsible for fatal septicemia caused by contaminated sea foods in eastern Asia. Quorum sensing (QS) is a cell-density dependent gene regulation mechanism that controls the expression of many virulence genes in various bacteria and V. vulnificus has been also suggested to express their virulence genes through the QS system. In this study, we investigated the role of QS system and QS-regulated exoproteases in the virulence of V. vulnificus using several invertebrate host models, Tenebrio molitor, an insect, Caenorhabditis elegans, a nematode, and brine shrimp (Artemia), an aquatic crustacean. When the culture supernatant of smcR (major QS regulator of V. vulnificus) mutant was injected to T. molitor larvae, it failed to induce the melanization of T. molitor larvae, while the culture supernatant of luxO (upstream negative regulator of smcR) mutant more strongly induced the melanization than wild type. These results demonstrated that QS system of V. vulnificus is crucial for virulence to T. molitor larvae. Among several QS-dependently expressed exoproteases of V. vulnificus, vvpE encoding a metalloprotease was mainly responsible for the melanization of T. molitor larvae, in that the culture supernatant of vvpE mutant failed to induce the melanization. This result was confirmed using the C. elegans and Artemia salina model systems, in which the vvpE mutant strains were attenuated in killing C. elegans and A. salina, compared with wild type, indicating that VvpE is important in the infection of V. vulnificus. In conclusion, we suggest that QS system and a QS-dependent exoprotease, VvpE are crucial for the V. vulnificus virulence to invertebrates. PMID:24769338

  11. Structural insights into the regulation of sialic acid catabolism by the Vibrio vulnificus transcriptional repressor NanR.

    PubMed

    Hwang, Jungwon; Kim, Byoung Sik; Jang, Song Yee; Lim, Jong Gyu; You, Dong-Ju; Jung, Hyun Suk; Oh, Tae-Kwang; Lee, Jie-Oh; Choi, Sang Ho; Kim, Myung Hee

    2013-07-23

    Pathogenic and commensal bacteria that experience limited nutrient availability in their host have evolved sophisticated systems to catabolize the mucin sugar N-acetylneuraminic acid, thereby facilitating their survival and colonization. The correct function of the associated catabolic machinery is particularly crucial for the pathogenesis of enteropathogenic bacteria during infection, although the molecular mechanisms involved with the regulation of the catabolic machinery are unknown. This study reports the complex structure of NanR, a repressor of the N-acetylneuraminate (nan) genes responsible for N-acetylneuraminic acid catabolism, and its regulatory ligand, N-acetylmannosamine 6-phosphate (ManNAc-6P), in the human pathogenic bacterium Vibrio vulnificus. Structural studies combined with electron microscopic, biochemical, and in vivo analysis demonstrated that NanR forms a dimer in which the two monomers create an arched tunnel-like DNA-binding space, which contains positively charged residues that interact with the nan promoter. The interaction between the NanR dimer and DNA is alleviated by the ManNAc-6P-mediated relocation of residues in the ligand-binding domain of NanR, which subsequently relieves the repressive effect of NanR and induces the transcription of the nan genes. Survival studies in which mice were challenged with a ManNAc-6P-binding-defective mutant strain of V. vulnificus demonstrated that this relocation of NanR residues is critical for V. vulnificus pathogenesis. In summary, this study presents a model of the mechanism that regulates sialic acid catabolism via NanR in V. vulnificus. PMID:23832782

  12. VgrG2 of type VI secretion system 2 of Vibrio parahaemolyticus induces autophagy in macrophages

    PubMed Central

    Yu, Ying; Fang, Lihua; Zhang, Yan; Sheng, Hongxia; Fang, Weihuan

    2015-01-01

    Type VI secretion system (T6SS) is a macromolecular transenvelope machine encoded within the genomes of several proteobacteria species. Vibrio parahaemolyticus contains two putative T6SS systems, VpT6SS1 and VpT6SS2, both contributing to adherence to Caco-2 and/or HeLa cells. However, it remains unknown if these systems are involved in cellular responses. In order to exclude the effects of other virulence factors known to induce cytotoxicity or autophagy, a triple deletion mutant dTTT (with deletion of tdh, and T3SS1 and T3SS2 structural protein genes) was used as the parent strain to construct deletion mutants of T6SS genes. The mutant dTTT-?icmF2, but not dTTT-?icmF1, reduced autophagic response upon 4 h of infection of the macrophage. Further attempt was made to search for the possible effector proteins that might be responsible for direct induction of autophagy by deletion of the genes encoding Hcp2 and VgrG2, two putative translocons of T6SS2 of V. parahaemolyticus. Deletion of either hcp2 or vgrG2 did reduce the autophagic response. However, increased LC3-II lipidation was seen only in the macrophage cells transfected with pVgrG2, but not with pHcp2. Chloroquinine treatment increased accumulation of LC3-II, suggesting that VgrG2 enhanced autophagic flux. The fact that vgrG2 deletion led to reduced level of intracellular cAMP suggests a possible role of cAMP signaling in autophagic responses to the bacterium. We conclude that VgrG2 of V. parahaemolyticus induces autophagy in macrophages.

  13. Effects of colonization, luminescence, and autoinducer on host transcription during development of the squid-vibrio association.

    PubMed

    Chun, Carlene K; Troll, Joshua V; Koroleva, Irina; Brown, Bartley; Manzella, Liliana; Snir, Einat; Almabrazi, Hakeem; Scheetz, Todd E; Bonaldo, Maria de Fatima; Casavant, Thomas L; Soares, M Bento; Ruby, Edward G; McFall-Ngai, Margaret J

    2008-08-12

    The light-organ symbiosis between the squid Euprymna scolopes and the luminous bacterium Vibrio fischeri offers the opportunity to decipher the hour-by-hour events that occur during the natural colonization of an animal's epithelial surface by its microbial partners. To determine the genetic basis of these events, a glass-slide microarray was used to characterize the light-organ transcriptome of juvenile squid in response to the initiation of symbiosis. Patterns of gene expression were compared between animals not exposed to the symbiont, exposed to the wild-type symbiont, or exposed to a mutant symbiont defective in either of two key characters of this association: bacterial luminescence or autoinducer (AI) production. Hundreds of genes were differentially regulated as a result of symbiosis initiation, and a hierarchy existed in the magnitude of the host's response to three symbiont features: bacterial presence > luminescence > AI production. Putative host receptors for bacterial surface molecules known to induce squid development are up-regulated by symbiont light production, suggesting that bioluminescence plays a key role in preparing the host for bacteria-induced development. Further, because the transcriptional response of tissues exposed to AI in the natural context (i.e., with the symbionts) differed from that to AI alone, the presence of the bacteria potentiates the role of quorum signals in symbiosis. Comparison of these microarray data with those from other symbioses, such as germ-free/conventionalized mice and zebrafish, revealed a set of shared genes that may represent a core set of ancient host responses conserved throughout animal evolution. PMID:18682555

  14. Dynamics of Vibrio with virulence genes detected in Pacific harbor seals (Phoca vitulina richardii) off California: implications for marine mammal health.

    PubMed

    Hughes, Stephanie N; Greig, Denise J; Miller, Woutrina A; Byrne, Barbara A; Gulland, Frances M D; Harvey, James T

    2013-05-01

    Given their coastal site fidelity and opportunistic foraging behavior, harbor seals (Phoca vitulina) may serve as sentinels for coastal ecosystem health. Seals using urbanized coastal habitat can acquire enteric bacteria, including Vibrio that may affect their health. To understand Vibrio dynamics in seals, demographic and environmental factors were tested for predicting potentially virulent Vibrio in free-ranging and stranded Pacific harbor seals (Phoca vitulina richardii) off California. Vibrio prevalence did not vary with season and was greater in free-ranging seals (29 %, n = 319) compared with stranded seals (17 %, n = 189). Of the factors tested, location, turbidity, and/or salinity best predicted Vibrio prevalence in free-ranging seals. The relationship of environmental factors with Vibrio prevalence differed by location and may be related to oceanographic or terrestrial contributions to water quality. Vibrio parahaemolyticus, Vibrio alginolyticus, and Vibrio cholerae were observed in seals, with V. cholerae found almost exclusively in stranded pups and yearlings. Additionally, virulence genes (trh and tdh) were detected in V. parahaemolyticus isolates. Vibrio cholerae isolates lacked targeted virulence genes, but were hemolytic. Three out of four stranded pups with V. parahaemolyticus (trh+ and/or tdh+) died in rehabilitation, but the role of Vibrio in causing mortality is unclear, and Vibrio expression of virulence genes should be investigated. Considering that humans share the environment and food resources with seals, potentially virulent Vibrio observed in seals also may be of concern to human health. PMID:23392641

  15. Temporal and spatial distribution patterns of potentially pathogenic Vibrio spp. at recreational beaches of the German north sea.

    PubMed

    Böer, Simone I; Heinemeyer, Ernst-August; Luden, Katrin; Erler, René; Gerdts, Gunnar; Janssen, Frank; Brennholt, Nicole

    2013-05-01

    The number of reported Vibrio-related wound infections associated with recreational bathing in Northern Europe has increased within the last decades. In order to study the health risk from potentially pathogenic Vibrio spp. in the central Wadden Sea, the seasonal and spatial distribution of Vibrio vulnificus, Vibrio parahaemolyticus, Vibrio alginolyticus and Vibrio cholerae were investigated at ten recreational beaches in this area over a 2-year period. V. alginolyticus and V. parahaemolyticus were found to be omnipresent all year round in the study area, while V. vulnificus occurrence was restricted to summer months in the estuaries of the rivers Ems and Weser. Multiple linear regression models revealed that water temperature is the most important determinant of Vibrio spp. occurrence in the area. Differentiated regression models showed a species-specific response to water temperature and revealed a particularly strong effect of even minor temperature increases on the probability of detecting V. vulnificus in summer. In sediments, Vibrio spp. concentrations were up to three orders of magnitude higher than in water. Also, V. alginolyticus and V. parahaemolyticus were found to be less susceptible towards winter temperatures in the benthic environment than in the water, indicating an important role of sediments for Vibrio ecology. While only a very small percentage of tested V. parahaemolyticus proved to be potentially pathogenic, the presence of V. vulnificus during the summer months should be regarded with care. PMID:23563708

  16. In-vitro antagonistic characteristics of crude aqueous and methanolic extracts of Garcinia kola (Heckel) seeds against some Vibrio bacteria.

    PubMed

    Penduka, Dambudzo; Okoh, Omobola O; Okoh, Anthony I

    2011-01-01

    The methanolic and aqueous extracts of Garcinia kola seeds were screened for their anti-Vibrio activities against 50 Vibrio isolates obtained from wastewater final effluents in the Eastern Cape Province, South Africa. The crude extracts at 10 mg/mL exhibited appreciable inhibitory activities against most of the test Vibrio isolates, with zones of inhibition ranging from 10-19 mm for methanol extract and 8-15 mm for the aqueous extracts. The minimum inhibitory concentrations (MIC) of the methanol extract varied from 0.313 to 2.5 mg/mL while that for the aqueous extract was 10 mg/mL for all the susceptible Vibrio isolates. Rate of kill assay of the methanolic extracts against three selected Vibrio species showed bacteriostatic activities against all of them achieving 58% and 60% (Vibrio vulnificus AL042); 68% and 69% (Vibrio parahaemolyticus AL049); and 70% and 78% (Vibrio fluvialis AL040) killing of the test bacteria at 3× and 4 ×MIC values, respectively, after 2 h exposure time. We conclude that Garcinia kola seeds hold promise as a potential source of therapeutic compounds of relevance in Vibrio infections management. PMID:21441874

  17. Pre-earthquake non-epidemic Vibrio cholerae in Haiti

    PubMed Central

    Liu, Jie; Winstead-Derlega, Christopher; Houpt, Eric; Heidkamp, Rebecca; Pape, Jean; Dillingham, Rebecca

    2014-01-01

    Introduction To our knowledge, there was no record of Vibrio cholerae in Haiti until the 2010 post earthquake outbreak. Methodology This study describes the analysis of 301 stool samples from 117 infants in Port-au-Prince, Haiti, who participated in a pediatric nutrition study between July 2008 and October 2009. Results Nine samples were identified positive with both SYBR Green and Taqman-MGB probe based molecular assays targeting V. cholerae hlyA and toxR, respectively (Ct = 33 – 40), but none were O1 or O139. Conclusions Our results from multiple molecular assays demonstrate the presence of non-O1/O139 V. cholerae DNA in stools collected from nine asymptomatic Haitian infants two years prior to the 2010 earthquake. PMID:24423722

  18. Nature of the Kanagawa phenomenon of Vibrio parahaemolyticus.

    PubMed Central

    Chun, D; Chung, J K; Tak, R; Seol, S Y

    1975-01-01

    In a study of the Kanagawa phenomenon of Vibrio parahaemolyticus, both Kanagawa-positive and -negative strains were found to produce hemolytic factors that could not be differentiated on Wagatsuma blood agar. The presence of fermentable carbohydrates in media containing high concentrations of NaCl promoted the growth of V. parahaemolyticus and resulted in a marked decrease in medium pH and increased hemolysin production. The Kanagawa hemolysis of test strains differed according to the carbohydrates added. Clearly defined Kanagawa hemolysis was observed in blood agars of high salt content, but the distinction was lost in media containing 3% NaCl. From the results of this study, the Kanagawa hemolysis was interpreted as an expression of quantitative difference in hemolysin production, a conclusion that is clearly demonstrated on special blood agar of high salt content. Images PMID:237836

  19. Probing control of glucose feeding in Vibrio cholerae cultivations.

    PubMed

    de Maré, L; Andersson, L; Hagander, P

    2003-01-01

    Infection with Vibrio cholerae is a significant problem in many developing countries. Cultivation of V. cholerae is used in production of cholera toxin B subunit, which is a component in a cholera vaccine. Fed-batch cultivations with V. cholerae in defined media have been conducted and reproducible results were obtained. A probing feeding strategy developed by Akesson for Escherichia coli cultivations has been tested. The strategy is working as well for V. cholerae as for E. coli in minimizing the amount of acetic acid formed and avoiding anaerobic conditions. At 2 h after the feed start most of the acetic acid accumulated during the batch phase is consumed. The resulting feed rate tends to be the highest possible with respect to the constraints from cell metabolism and mass transfer, thus maximizing productivity in terms of biomass. A cell dry weight of 20-23 g/l is obtained after 12 h of feeding. PMID:14505000

  20. Attachment of Vibrio parahaemolyticus strains to estuarine algae.

    PubMed

    Kumazawa, N H; Fukuma, N; Komoda, Y

    1991-04-01

    Attachment of Vibrio parahaemolyticus strains to estuarine microalgae was examined in artificial seawater by viable counts of the organism and direct counts of the bacterial cells after immunoperoxidase staining. Thermostable direct hemolysin (TDH)-producing and TDH-non-producing strains of V. parahaemolyticus were found to attach to five estuarine strains of Navicula (diatom alga) in similar levels. The level of the bacterial attachment depended on salinity and temperature of the water, in which the maximum attachment was observed in 15% artificial seawater at 25 degrees C, a typical condition of Hashizu estuary in Japan during summer months. The attachment was inhibited by pectinase digestion of the algal cells. These evidences confirmed the participation of the microalgae to the ecological cycle of V. parahaemolyticus at the estuary. PMID:1830790

  1. Temporal Quorum-Sensing Induction Regulates Vibrio cholerae Biofilm Architecture?

    PubMed Central

    Liu, Zhi; Stirling, Fiona R.; Zhu, Jun

    2007-01-01

    Vibrio cholerae, the pathogen that causes cholera, also survives in aqueous reservoirs, probably in the form of biofilms. Quorum sensing negatively regulates V. cholerae biofilm formation through HapR, whose expression is induced at a high cell density. In this study, we show that the concentration of the quorum-sensing signal molecule CAI-1 is higher in biofilms than in planktonic cultures. By measuring hapR expression and activity, we found that the induction of quorum sensing in biofilm-associated cells occurs earlier. We further demonstrate that the timing of hapR expression is crucial for biofilm thickness, biofilm detachment rates, and intestinal colonization efficiency. These results suggest that V. cholerae is able to regulate its biofilm architecture by temporal induction of quorum-sensing systems. PMID:17074850

  2. Comparison of Molecular Methods for Typing Vibrio parahaemolyticus

    PubMed Central

    Marshall, S.; Clark, C. G.; Wang, G.; Mulvey, M.; Kelly, M. T.; Johnson, W. M.

    1999-01-01

    An outbreak of Vibrio parahaemolyticus gastroenteritis on Canada’s west coast in 1997 emphasized the need to develop molecular methods for differentiation and typing of these organisms. Isolates were analyzed by enterobacterial repetitive intergenic consensus sequence (ERIC) PCR, detection of restriction fragment length polymorphisms (RFLP) in rRNA genes (ribotyping), pulsed-field gel electrophoresis (PFGE), and RFLP analysis of the genetic locus encoding the polar flagellum (Fla locus RFLP analysis). ERIC PCR and ribotyping were the most informative typing methods, especially when used together, while Fla locus RFLP analysis was the least discriminatory. PFGE exhibited good discrimination but suffered from a high incidence of DNA degradation. ERIC PCR and ribotyping will be useful for the evaluation of genetic and epidemiological relationships among V. parahaemolyticus strains. PMID:10405387

  3. Association of a d-Alanyl-d-Alanine Carboxypeptidase Gene with the Formation of Aberrantly Shaped Cells during the Induction of Viable but Nonculturable Vibrio parahaemolyticus

    PubMed Central

    Hung, Wei-cheng; Jane, Wann-Neng

    2013-01-01

    Vibrio parahaemolyticus is a halophilic Gram-negative bacterium that causes human gastroenteritis. When the viable but nonculturable (VBNC) state of this bacterium was induced by incubation at 4°C in Morita minimal salt solution containing 0.5% NaCl, the rod-shaped cells became coccoid, and various aberrantly shaped intermediates were formed in the initial stage. This study examined the factors that influence the formation of these aberrantly shaped cells. The proportion of aberrantly shaped cells was not affected in a medium containing d-cycloserine (50 ?g/ml) but was lower in a medium containing cephalosporin C (10 ?g/ml) than in the control medium without antibiotics. The proportion of aberrantly shaped cells was higher in a culture medium that contained 0.5% NaCl than in culture media containing 1.0 or 1.5% NaCl. The expression of 15 of 17 selected genes associated with cell wall synthesis was enhanced, and the expression of VP2468 (dacB), which encodes d-alanyl-d-alanine carboxypeptidase, was enhanced the most. The proportion of aberrantly shaped cells was significantly lower in the dacB mutant strain than in the parent strain, but the proportion was restored in the presence of the complementary dacB gene. This study suggests that disturbance of the dynamics of cell wall synthesis by enhanced expression of the VP2468 gene is associated with the formation of aberrantly shaped cells in the initial stage of induction of VBNC V. parahaemolyticus cells under specific conditions. PMID:24056454

  4. Manganese uptake in marine bacteria; the novel MntX transporter is widespread in Roseobacters, Vibrios, Alteromonadales and the SAR11 and SAR116 clades

    PubMed Central

    Green, Robert T; Todd, Jonathan D; Johnston, Andrew W B

    2013-01-01

    We showed that two very different manganese transporters occur in various important genera of marine bacteria. The ABC transporter encoded by sitABCD of the model Roseobacter-clade bacterium Ruegeria pomeroyi DSS-3 is required for Mn2+ import and was repressed by the Mur (Manganese uptake regulator) transcriptional regulator in Mn-replete media. Most genome-sequenced Roseobacter strains contain SitABCD, which are in at least two sub-groups, judged by their amino-acid sequences. However, a few Roseobacters, for example, Roseovarius nubinhibens, lack sitABCD, but these contain another gene, mntX, which encodes a predicted inner membrane polypeptide and is preceded by cis-acting Mur-responsive MRS sequences. It was confirmed directly that mntX of Roseovarius nubinhibens encodes a manganese transporter that was required for growth in Mn-depleted media and that its expression was repressed by Mur in Mn-replete conditions. MntX homologues occur in the deduced proteomes of several bacterial species. Strikingly, all of these live in marine habitats, but are in distantly related taxonomic groups, in the ?- and ?-proteobacteria. Notably, MntX was prevalent in nearly all strains of Vibrionales, including the important pathogen, Vibrio cholerae. It also occurs in a strain of the hugely abundant Candidatus Pelagibacter (SAR11), and in another populous marine bacterium, Candidatus Puniceispirillum marinum (SAR116). Consistent with this, MntX was abundant in marine bacterial metagenomes, with one sub-type occurring in an as-yet unknown bacterial clade. PMID:23190726

  5. Extreme Ionizing-Radiation-Resistant Bacterium

    NASA Technical Reports Server (NTRS)

    Vaishampayan, Parag A.; Venkateswaran, Kasthuri J.; Schwendner, Petra

    2012-01-01

    There is a growing concern that desiccation and extreme radiation-resistant, non-spore-forming microorganisms associated with spacecraft surfaces can withstand space environmental conditions and subsequent proliferation on another solar body. Such forward contamination would jeopardize future life detection or sample return technologies. The prime focus of NASA s planetary protection efforts is the development of strategies for inactivating resistance-bearing microorganisms. Eradification techniques can be designed to target resistance-conferring microbial populations by first identifying and understanding their physiologic and biochemical capabilities that confers its elevated tolerance (as is being studied in Deinococcus phoenicis, as a result of this description). Furthermore, hospitals, food, and government agencies frequently use biological indicators to ensure the efficacy of a wide range of radiation- based sterilization processes. Due to their resistance to a variety of perturbations, the non-spore forming D. phoenicis may be a more appropriate biological indicator than those currently in use. The high flux of cosmic rays during space travel and onto the unshielded surface of Mars poses a significant hazard to the survival of microbial life. Thus, radiation-resistant microorganisms are of particular concern that can survive extreme radiation, desiccation, and low temperatures experienced during space travel. Spore-forming bacteria, a common inhabitant of spacecraft assembly facilities, are known to tolerate these extreme conditions. Since the Viking era, spores have been utilized to assess the degree and level of microbiological contamination on spacecraft and their associated spacecraft assembly facilities. Members of the non-spore-forming bacterial community such as Deinococcus radiodurans can survive acute exposures to ionizing radiation (5 kGy), ultraviolet light (1 kJ/sq m), and desiccation (years). These resistive phenotypes of Deinococcus enhance the potential for transfer, and subsequent proliferation, on another solar body such as Mars and Europa. These organisms are more likely to escape planetary protection assays, which only take into account presence of spores. Hence, presences of extreme radiation-resistant Deinococcus in the cleanroom facility where spacecraft are assembled pose a serious risk for integrity of life-detection missions. The microorganism described herein was isolated from the surfaces of the cleanroom facility in which the Phoenix Lander was assembled. The isolated bacterial strain was subjected to a comprehensive polyphasic analysis to characterize its taxonomic position. This bacterium exhibits very low 16SrRNA similarity with any other environmental isolate reported to date. Both phenotypic and phylogenetic analyses clearly indicate that this isolate belongs to the genus Deinococcus and represents a novel species. The name Deinococcus phoenicis was proposed after the Phoenix spacecraft, which was undergoing assembly, testing, and launch operations in the spacecraft assembly facility at the time of isolation. D. phoenicis cells exhibited higher resistance to ionizing radiation (cobalt-60; 14 kGy) than the cells of the D. radiodurans (5 kGy). Thus, it is in the best interest of NASA to thoroughly characterize this organism, which will further assess in determining the potential for forward contamination. Upon the completion of genetic and physiological characteristics of D. phoenicis, it will be added to a planetary protection database to be able to further model and predict the probability of forward contamination.

  6. Extreme Ionizing-Radiation-Resistant Bacterium

    NASA Technical Reports Server (NTRS)

    Vaishampayan, Parag A.; Venkateswaran, Kasthuri J.; Schwendner, Petra

    2013-01-01

    There is a growing concern that desiccation and extreme radiation-resistant, non-spore-forming microorganisms associated with spacecraft surfaces can withstand space environmental conditions and subsequent proliferation on another solar body. Such forward contamination would jeopardize future life detection or sample return technologies. The prime focus of NASA s planetary protection efforts is the development of strategies for inactivating resistance-bearing micro-organisms. Eradi cation techniques can be designed to target resistance-conferring microbial populations by first identifying and understanding their physiologic and biochemical capabilities that confers its elevated tolerance (as is being studied in Deinococcus phoenicis, as a result of this description). Furthermore, hospitals, food, and government agencies frequently use biological indicators to ensure the efficacy of a wide range of radiation-based sterilization processes. Due to their resistance to a variety of perturbations, the nonspore forming D. phoenicis may be a more appropriate biological indicator than those currently in use. The high flux of cosmic rays during space travel and onto the unshielded surface of Mars poses a significant hazard to the survival of microbial life. Thus, radiation-resistant microorganisms are of particular concern that can survive extreme radiation, desiccation, and low temperatures experienced during space travel. Spore-forming bacteria, a common inhabitant of spacecraft assembly facilities, are known to tolerate these extreme conditions. Since the Viking era, spores have been utilized to assess the degree and level of microbiological contamination on spacecraft and their associated spacecraft assembly facilities. Members of the non-sporeforming bacterial community such as Deinococcus radiodurans can survive acute exposures to ionizing radiation (5 kGy), ultraviolet light (1 kJ/m2), and desiccation (years). These resistive phenotypes of Deinococcus enhance the potential for transfer, and subsequent proliferation, on another solar body such as Mars and Europa. These organisms are more likely to escape planetary protection assays, which only take into account presence of spores. Hence, presences of extreme radiation-resistant Deinococcus in the cleanroom facility where spacecraft are assembled pose a serious risk for integrity of life-detection missions. The microorganism described herein was isolated from the surfaces of the cleanroom facility in which the Phoenix Lander was assembled. The isolated bacterial strain was subjected to a comprehensive polyphasic analysis to characterize its taxonomic position. This bacterium exhibits very low 16SrRNA similarity with any other environmental isolate reported to date. Both phenotypic and phylogenetic analyses clearly indicate that this isolate belongs to the genus Deinococcus and represents a novel species. The name Deinococcus phoenicis was proposed after the Phoenix spacecraft, which was undergoing assembly, testing, and launch operations in the spacecraft assembly facility at the time of isolation. D. phoenicis cells exhibited higher resistance to ionizing radiation (cobalt-60; 14 kGy) than the cells of the D. radiodurans (5 kGy). Thus, it is in the best interest of NASA to thoroughly characterize this organism, which will further assess in determining the potential for forward contamination. Upon the completion of genetic and physiological characteristics of D. phoenicis, it will be added to a planetary protection database to be able to further model and predict the probability of forward contamination.

  7. Relationships between Environmental Factors and Pathogenic Vibrios in the Northern Gulf of Mexico ? †

    PubMed Central

    Johnson, C. N.; Flowers, A. R.; Noriea, N. F.; Zimmerman, A. M.; Bowers, J. C.; DePaola, A.; Grimes, D. J.

    2010-01-01

    Although autochthonous vibrio densities are known to be influenced by water temperature and salinity, little is understood about other environmental factors associated with their abundance and distribution. Densities of culturable Vibrio vulnificus containing vvh (V. vulnificus hemolysin gene) and V. parahaemolyticus containing tlh (thermolabile hemolysin gene, ubiquitous in V. parahaemolyticus), tdh (thermostable direct hemolysin gene, V. parahaemolyticus pathogenicity factor), and trh (tdh-related hemolysin gene, V. parahaemolyticus pathogenicity factor) were measured in coastal waters of Mississippi and Alabama. Over a 19-month sampling period, vibrio densities in water, oysters, and sediment varied significantly with sea surface temperature (SST). On average, tdh-to-tlh ratios were significantly higher than trh-to-tlh ratios in water and oysters but not in sediment. Although tlh densities were lower than vvh densities in water and in oysters, the opposite was true in sediment. Regression analysis indicated that SST had a significant association with vvh and tlh densities in water and oysters, while salinity was significantly related to vibrio densities in the water column. Chlorophyll a levels in the water were correlated significantly with vvh in sediment and oysters and with pathogenic V. parahaemolyticus (tdh and trh) in the water column. Furthermore, turbidity was a significant predictor of V. parahaemolyticus density in all sample types (water, oyster, and sediment), and its role in predicting the risk of V. parahaemolyticus illness may be more important than previously realized. This study identified (i) culturable vibrios in winter sediment samples, (ii) niche-based differences in the abundance of vibrios, and (iii) predictive signatures resulting from correlations between environmental parameters and vibrio densities. PMID:20817802

  8. Environmental influences on Vibrio populations in northern temperate and boreal coastal waters (Baltic and Skagerrak Seas).

    PubMed

    Eiler, Alexander; Johansson, Mona; Bertilsson, Stefan

    2006-09-01

    Even if many Vibrio spp. are endemic to coastal waters, their distribution in northern temperate and boreal waters is poorly studied. To identify environmental factors regulating Vibrio populations in a salinity gradient along the Swedish coastline, we combined Vibrio-specific quantitative competitive PCR with denaturant gradient gel electrophoresis-based genotyping. The total Vibrio abundance ranged from 4 x 10(3) to 9.6 x 10(4) cells liter(-1), with the highest abundances in the more saline waters of the Skagerrak Sea. Several Vibrio populations were present throughout the salinity gradient, with abundances of single populations ranging from 5 x 10(2) to 7 x 10(4) cells liter(-1). Clear differences were observed along the salinity gradient, where three populations dominated the more saline waters of the Skagerrak Sea and two populations containing mainly representatives of V. anguillarum and V. aestuarianus genotypes were abundant in the brackish waters of the Baltic Sea. Our results suggest that this apparent niche separation within the genus Vibrio may also be influenced by alternate factors such as nutrient levels and high abundances of dinoflagellates. A V. cholerae/V. mimicus population was detected in more than 50% of the samples, with abundances exceeding 10(3) cells liter(-1), even in the cold (annual average water temperature of around 5 degrees C) and low-salinity (2 to 4 per thousand) samples from the Bothnian Bay (latitude, 65 degrees N). The unsuspected and widespread occurrence of this population in temperate and boreal coastal waters suggests that potential Vibrio pathogens may also be endemic to cold and brackish waters and hence may represent a previously overlooked health hazard. PMID:16957222

  9. Ecology of Vibrio vulnificus in Estuarine Waters of Eastern North Carolina

    PubMed Central

    Pfeffer, Courtney S.; Hite, M. Frances; Oliver, James D.

    2003-01-01

    While several studies on the ecology of Vibrio vulnificus in Gulf Coast environments have been reported, there is little information on the distribution of this pathogen in East Coast waters. Thus, we conducted a multiyear study on the ecology of V. vulnificus in estuarine waters of the eastern United States, employing extensive multiple regression analyses to reveal the major environmental factors controlling the presence of this pathogen, and of Vibrio spp., in these environments. Monthly field samplings were conducted between July 2000 and April 2002 at six different estuarine sites along the eastern coast of North Carolina. At each site, water samples were taken and nine physicochemical parameters were measured. V. vulnificus isolates, along with estuarine bacteria, Vibrio spp., Escherichia coli organisms, and total coliforms, were enumerated in samples from each site by using selective media. During the last 6 months of the study, sediment samples were also analyzed for the presence of vibrios, including V. vulnificus. Isolates were confirmed as V. vulnificus by using hemolysin gene PCR or colony hybridization. V. vulnificus was isolated only when water temperatures were between 15 and 27°C, and its presence correlated with water temperature and dissolved oxygen and vibrio levels. Levels of V. vulnificus in sediments were low, and no evidence for an overwintering in this environment was found. Multiple regression analysis indicated that vibrio levels were controlled primarily by temperature, turbidity, and levels of dissolved oxygen, estuarine bacteria, and coliforms. Water temperature accounted for most of the variability in the concentrations of both V. vulnificus (47%) and Vibrio spp. (48%). PMID:12788759

  10. Comparative analysis of induction of osmotic-stress-dependent genes in Vibrio vulnificus exposed to hyper- and hypo-osmotic stress.

    PubMed

    Rao, Namrata V; Shashidhar, Ravindranath; Bandekar, Jayant R

    2013-05-01

    Vibrio vulnificus, a halophilic pathogenic bacterium of marine environments, encounters changes in salinity in its natural habitat and in the food-processing environment. The comparative response of V. vulnificus to hyperosmotic and hypoosmotic stress in terms of gene expression was investigated. Genes belonging to the proU operon for transport of compatible solutes and compatible solute synthesis were significantly upregulated (3- to 4.7-fold) under hyperosmotic stress. Under hypoosmotic stress, upregulation of genes coding for mechanosensitive channels of small conductance (mscS) was not observed. In hyperosmotic conditions a 2.3-fold decrease in the expression of aqpZ was observed. A 2-fold induction in gyrA was observed in V. vulnificus cells on exposure to hyperosmotic stress. groEL genes, VVA1659 (1.6-fold), and VV3106 (1-fold) were induced in hypoosmotic condition. Results of this study indicate that to manage hyperosmotic stress, V. vulnificus accumulated osmoprotectants through uptake or through endogenous synthesis of compatible solutes. Expression of mscS may not be necessary for immediate protection in cells exposed to hyper- and hypo-osmotic stress. Comparative analysis of important osmotic-stress-related genes showed up- or down-regulation of 14 genes in hyperosmotic stress as compared with up- or down-regulation of only 7 genes in hypoosmotic stress, indicating that the cells respond asymmetrically to hyper- and hypo-osmotic stress. PMID:23647346

  11. In vitro and in vivo antimicrobial efficacy of natural plant-derived compounds against Vibrio cholerae of O1 El Tor Inaba serotype.

    PubMed

    Kim, Hyung-Ip; Kim, Ji-Ae; Choi, Eun-Jin; Harris, Jason B; Jeong, Seong-Yeop; Son, Seok-Jun; Kim, Younghoon; Shin, Ok Sarah

    2015-03-01

    In this study, we investigated antibacterial activities of 20 plant-derived natural compounds against Gram-negative enteric pathogens. We found that both flavonoids and non-flavonoids, including honokiol and magnolol, possess specific antibacterial activities against V. cholerae, but not against other species of Gram-negative bacterium which we tested. Using various antibacterial assays, we determined that there was a dose-dependent bactericidal and biofilm inhibitory activity of honokiol and magnolol against Vibrio cholerae. In addition to antibacterial activities, these molecules also induced an attenuating effect on reactive oxygen species (ROS) production and pro-inflammatory responses generated by macrophages in response to lipopolysaccharides (LPS). Additionally, Caenorhabditis elegans lethality assay revealed that honokiol and magnolol have an ability to extend a lifespan of V. cholerae-infected worms, contributing to prolonged survival of worms after lethal infection. Altogether, our data show for the first time that honokiol and magnolol may be considered as attractive protective or preventive food adjuncts for cholera. PMID:25516242

  12. Study of the variation of ecotoxicity at different stages of domestic wastewater treatment using Vibrio-qinghaiensis sp.-Q67.

    PubMed

    Ma, Xiaoyan Y; Wang, Xiaochang C; Liu, Yongjun J

    2011-06-15

    A bioassay using the luminescent bacterium Vibrio-qinghaiensis sp.-Q67 associated with solid-phase extraction (SPE) was developed for evaluating the variation of ecotoxicity along with the reduction of organic substances in a domestic wastewater treatment plant employing an oxidation ditch process. With effective elimination of the interference from all inorganic substances by the SPE operation, the ecotoxicity of the water, as expressed by the toxicity impact index, TII(50) (%) after a model-based regression and parameter transformation, was found to decrease from 50.51% in the influent to 25.84% after the grid chamber and then to 1.38% for the secondary effluent, but the final chlorination stage resulted in a slight TII(50) increase. Of the two typical tertiary treatment processes, coagulation could not assist further reduction of the ecotoxicity while carbon adsorption could reduce the TII(50) to as low as 0.96%. When enhanced primary treatment was conducted, the influent TII(50) could be directly reduced to 7.36%. A good correlative relationship was found between the total COD concentration and the TII(50) value at different stages of the wastewater treatment process. PMID:21440989

  13. Vibrio cholerae Persisted in Microcosm for 700 Days Inhibits Motility but Promotes Biofilm Formation in Nutrient-Poor Lake Water Microcosms

    PubMed Central

    Jubair, Mohammad; Atanasova, Kalina R.; Rahman, Mustafizur; Klose, Karl E.; Yasmin, Mahmuda; Yilmaz, Özlem; Morris, J. Glenn; Ali, Afsar

    2014-01-01

    Toxigenic Vibrio cholerae, ubiquitous in aquatic environments, is responsible for cholera; humans can become infected after consuming food and/or water contaminated with the bacterium. The underlying basis of persistence of V. cholerae in the aquatic environment remains poorly understood despite decades of research. We recently described a “persister” phenotype of V. cholerae that survived in nutrient-poor “filter sterilized” lake water (FSLW) in excess of 700-days. Previous reports suggest that microorganisms can assume a growth advantage in stationary phase (GASP) phenotype in response to long-term survival during stationary phase of growth. Here we report a V. cholerae GASP phenotype (GASP-700D) that appeared to result from 700 day-old persister cells stored in glycerol broth at ?80°C. The GASP-700D, compared to its wild-type N16961, was defective in motility, produced increased biofilm that was independent of vps (p<0.005) and resistant to oxidative stress when grown specifically in FSLW (p<0.005). We propose that V. cholerae GASP-700D represents cell populations that may better fit and adapt to stressful survival conditions while serving as a critical link in the cycle of cholera transmission. PMID:24667909

  14. The 1.59Å resolution structure of the minor pseudopilin EpsH of Vibrio cholerae reveals a long flexible loop.

    PubMed

    Raghunathan, Kannan; Vago, Frank S; Grindem, David; Ball, Terry; Wedemeyer, William J; Bagdasarian, Michael; Arvidson, Dennis N

    2014-02-01

    The type II secretion complex exports folded proteins from the periplasm to the extracellular milieu. It is used by the pathogenic bacterium Vibrio cholerae to export several proteins, including its major virulence factor, cholera toxin. The pseudopilus is an essential component of the type II secretion system and likely acts as a piston to push the folded proteins across the outer membrane through the secretin pore. The pseudopilus is composed of the major pseudopilin, EpsG, and four minor pseudopilins, EpsH, EpsI, EpsJ and EpsK. We determined the x-ray crystal structure of the head domain of EpsH at 1.59Å resolution using molecular replacement with the previously reported EpsH structure, 2qv8, as the template. Three additional N-terminal amino acids present in our construct prevent an artifactual conformation of residues 160-166, present in one of the two monomers of the 2qv8 structure. Additional crystal contacts stabilize a long flexible loop comprised of residues 104-135 that is more disordered in the 2qv8 structure but is partially observed in our structure in very different positions for the two EpsH monomers in the asymmetric unit. In one of the conformations the loop is highly extended. Modeling suggests the highly charged loop is capable of contacting EpsG and possibly secreted protein substrates, suggesting a role in specificity of pseudopilus assembly or secretion function. PMID:24316251

  15. Complete Genome of the Cellulolytic Ruminal Bacterium Ruminococcus albus 7

    SciTech Connect

    Suen, Garret [University of Wisconsin, Madison; Stevenson, David M [USDA-ARS, Madison WI; Bruce, David [Los Alamos National Laboratory (LANL); Chertkov, Olga [Los Alamos National Laboratory (LANL); Copeland, A [U.S. Department of Energy, Joint Genome Institute; Cheng, Jan-Fang [U.S. Department of Energy, Joint Genome Institute; Detter, J. Chris [U.S. Department of Energy, Joint Genome Institute; Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Han, Cliff [Los Alamos National Laboratory (LANL); Hauser, Loren John [ORNL; Ivanova, N [U.S. Department of Energy, Joint Genome Institute; Kyrpides, Nikos C [U.S. Department of Energy, Joint Genome Institute; Land, Miriam L [ORNL; Lapidus, Alla L. [U.S. Department of Energy, Joint Genome Institute; Lucas, Susan [U.S. Department of Energy, Joint Genome Institute; Ovchinnikova, Galina [U.S. Department of Energy, Joint Genome Institute; Pitluck, Sam [U.S. Department of Energy, Joint Genome Institute; Tapia, Roxanne [Los Alamos National Laboratory (LANL); Woyke, Tanja [U.S. Department of Energy, Joint Genome Institute; Boyum, Julie [University of Wisconsin, Madison; Mead, David [University of Wisconsin, Madison; Weimer, Paul J [USDA-ARS, Madison WI

    2011-01-01

    Ruminococcus albus 7 is a highly cellulolytic ruminal bacterium that is a member of the phylum Firmicutes. Here, we describe the complete genome of this microbe. This genome will be useful for rumen microbiology and cellulosome biology and in biofuel production, as one of its major fermentation products is ethanol.

  16. Novel Sulfonolipid in the Extremely Halophilic Bacterium Salinibacter ruber

    Microsoft Academic Search

    Angela Corcelli; Veronica M. T. Lattanzio; Giuseppe Mascolo; Francesco Babudri; Aharon Oren; Morris Kates

    2004-01-01

    Salinibacter ruber is an extremely halophilic bacterium, phylogenetically affiliated with the Flavobacterium\\/ Cytophaga branch of the domain Bacteria. Electrospray mass analyses (negative ion) of the total lipid extract of a pure culture of S. ruber shows a characteristic peak at m\\/z 660 as the most prominent peak in the high-mass range of the spectrum. A novel sulfonolipid, giving rise to

  17. Complete genome of the cellulolytic ruminal bacterium Ruminococcus albus 7

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ruminococcus albus 7 is a highly cellulolytic rumen bacterium that is a member of the phylum Firmicutes. Here, we describe the complete genome for this microbe. This genome will be useful for rumen microbiology, cellulosome biology, and in biofuel production, as one of its major fermentation product...

  18. Suppression of plant defence response by a mycorrhiza helper bacterium

    Microsoft Academic Search

    Nina A. Lehr; Silvia D. Schrey; Robert Bauer; Rüdiger Hampp; Mika T. Tarkka

    2007-01-01

    Summary • The aim of the present study was to determine whether the mycorrhiza helper bacterium Streptomyces sp. AcH 505 could serve as a biocontrol agent against Heterobasidion root and butt rot. • Bacterial influence on mycelial growth of Heterobasidion sp. isolates, on the colonization of wood discs and Norway spruce ( Picea abies ) roots was determined. The effect

  19. A Filamentous Bacterium on the Brine Shrimp and Its Control

    Microsoft Academic Search

    Mobashir A. Solangi; Robin M. Overstreet; Ann L. Gannam

    1979-01-01

    A strain of a colorless, filamentous bacterium (tentatively identified as Leucothrix mucor) heavily infests the brine shrimp, Artemia salina. Its ultrastructure, unlike that of some other strains, does not reveal a distinct middle layer between its outer cell wall layer and cytoplasmic membrane, irregular blebs extending from the cell layers, or an external sheath. An entire infestation, represented as a

  20. An annotated cDNA library of juvenile Euprymna scolopes with and without colonization by the symbiont Vibrio fischeri

    Microsoft Academic Search

    Carlene K Chun; Todd E Scheetz; Maria de Fatima Bonaldo; Bartley Brown; Anik Clemens; Wendy J Crookes-Goodson; Keith Crouch; Tad DeMartini; Mari Eyestone; Michael S Goodson; Bernadette Janssens; Jennifer L Kimbell; Tanya A Koropatnick; Tamara Kucaba; Christina Smith; Jennifer J Stewart; Deyan Tong; Joshua V Troll; Sarahrose Webster; Jane Winhall-Rice; Cory Yap; Thomas L Casavant; Margaret J McFall-Ngai; M Bento Soares

    2006-01-01

    BACKGROUND: Biologists are becoming increasingly aware that the interaction of animals, including humans, with their coevolved bacterial partners is essential for health. This growing awareness has been a driving force for the development of models for the study of beneficial animal-bacterial interactions. In the squid-vibrio model, symbiotic Vibrio fischeri induce dramatic developmental changes in the light organ of host Euprymna

  1. Dominance of Vibrio fischeri in Secreted Mucus outside the Light Organ of Euprymna scolopes: the First Site of Symbiont Specificity

    NSDL National Science Digital Library

    McFall-Ngai, Margaret Jean

    This Applied and Environmental Microbiology article provides evidence that the specificity of the squid-vibrio (Euprymna scolopes - Vibrio fischeri) symbiosis begins early in their interaction, when they aggregate in the mucus surrounding the light organ. Links are provided to cited references and a PDF version.

  2. Functional chimeras of flagellar stator proteins between E. coli MotB and Vibrio PomB at the periplasmic region in Vibrio or E. coli

    PubMed Central

    Nishino, Yuuki; Onoue, Yasuhiro; Kojima, Seiji; Homma, Michio

    2015-01-01

    The bacterial flagellar motor has a stator and a rotor. The stator is composed of two membrane proteins, MotA and MotB in Escherichia coli and PomA and PomB in Vibrio alginolyticus. The Vibrio motor has a unique structure, the T ring, which is composed of MotX and MotY. Based on the structural information of PomB and MotB, we constructed three chimeric proteins between PomB and MotB, named PotB91, PotB129, and PotB138, with various chimeric junctions. When those chimeric proteins were produced with PomA in a ?motAB strain of E. coli or in ?pomAB and ?pomAB ?motX strains of Vibrio, all chimeras were functional in E. coli or Vibrio, either with or without the T ring, although the motilities were very weak in E. coli. Furthermore, we could isolate some suppressors in E. coli and identified the mutation sites on PomA or the chimeric B subunit. The weak function of chimeric PotBs in E. coli is derived mainly from the defect in the rotational switching of the flagellar motor. In addition, comparing the motilities of chimera strains in ?pomAB, PotB138 had the highest motility. The difference between the origin of the ?1 and ?2 helices, E. coli MotB or Vibro PomB, seems to be important for motility in E. coli and especially in Vibrio. PMID:25630862

  3. ULTRASTRUCTURE OF LIGHT ORGANS OF LOLIGINID SQUIDS AND THEIR BACTERIAL SYMBIONTS: A NOVEL MODEL SYSTEM FOR THE STUDY OF MARINE SYMBIOSES

    PubMed Central

    GUERRERO-FERREIRA, R. C.; NISHIGUCHI, M. K.

    2010-01-01

    The class Cephalopoda (Phylum Mollusca), encompassing squids and octopuses, contains multiple species that are characterized by the presence of specialized organs known to emit light. These complex organs have a variety of morphological characteristics ranging from groups of simple, light-producing cells, to highly specialized organs (light organs) with cells surrounded by reflectors, lenses, light guides, color filters, and muscles. Bacteriogenic light organs have been well characterized in sepiolid squids, but a number of species in the family Loliginidae are also known to contain bacteriogenic light organs. Interest in loliginid light organ structure has recently arisen because of their potential as ecological niches for Vibrio harveyi, a pathogenic marine bacterium. This also implies the importance of loliginid light organs as reservoirs for V. harveyi persistence in the ocean. The present study utilized transmission and scanning electron microscopy to characterize the morphology of loliginid light organs and determined the location of bacterial symbiont cells within the tissue. It was determined that the rod-shaped loliginid symbionts lack flagella, as similarly observed in other light organ-associated bacteria. Also, the interaction of individual cells to light organ tissue is not as defined as reported for other squid-Vibrio systems. In addition, SEM observations show the presence of two pores leading to the bacterial chamber. Data presented here offer support for the hypothesis of environmental transfer of bacterial symbionts in loliginid squids. PMID:21152248

  4. Comparative genomic analysis of Vibrio parahaemolyticus: serotype conversion and virulence

    PubMed Central

    2011-01-01

    Background Vibrio parahaemolyticus is a common cause of foodborne disease. Beginning in 1996, a more virulent strain having serotype O3:K6 caused major outbreaks in India and other parts of the world, resulting in the emergence of a pandemic. Other serovariants of this strain emerged during its dissemination and together with the original O3:K6 were termed strains of the pandemic clone. Two genomes, one of this virulent strain and one pre-pandemic strain have been sequenced. We sequenced four additional genomes of V. parahaemolyticus in this study that were isolated from different geographical regions and time points. Comparative genomic analyses of six strains of V. parahaemolyticus isolated from Asia and Peru were performed in order to advance knowledge concerning the evolution of V. parahaemolyticus; specifically, the genetic changes contributing to serotype conversion and virulence. Two pre-pandemic strains and three pandemic strains, isolated from different geographical regions, were serotype O3:K6 and either toxin profiles (tdh+, trh-) or (tdh-, trh+). The sixth pandemic strain sequenced in this study was serotype O4:K68. Results Genomic analyses revealed that the trh+ and tdh+ strains had different types of pathogenicity islands and mobile elements as well as major structural differences between the tdh pathogenicity islands of the pre-pandemic and pandemic strains. In addition, the results of single nucleotide polymorphism (SNP) analysis showed that 94% of the SNPs between O3:K6 and O4:K68 pandemic isolates were within a 141 kb region surrounding the O- and K-antigen-encoding gene clusters. The "core" genes of V. parahaemolyticus were also compared to those of V. cholerae and V. vulnificus, in order to delineate differences between these three pathogenic species. Approximately one-half (49-59%) of each species' core genes were conserved in all three species, and 14-24% of the core genes were species-specific and in different functional categories. Conclusions Our data support the idea that the pandemic strains are closely related and that recent South American outbreaks of foodborne disease caused by V. parahaemolyticus are closely linked to outbreaks in India. Serotype conversion from O3:K6 to O4:K68 was likely due to a recombination event involving a region much larger than the O-antigen- and K-antigen-encoding gene clusters. Major differences between pathogenicity islands and mobile elements are also likely driving the evolution of V. parahaemolyticus. In addition, our analyses categorized genes that may be useful in differentiating pathogenic Vibrios at the species level. PMID:21645368

  5. Phenotypic Characteristics and Virulence of Vibrio anguillarum-Related Organisms

    PubMed Central

    Pazos, F.; Santos, Y.; Magariños, B.; Bandín, I.; Núñez, S.; Toranzo, A. E.

    1993-01-01

    The phenotypic, molecular, and virulence properties of 46 Vibrio anguillarum-related (VAR) strains isolated from diseased fish and shellfish and from the environment were investigated. Twelve reference strains belonging to the 10 serotypes of V. anguillarum and the Vibrio splendidus type strain were included for comparison. Numerical taxonomy studies allowed us to group the isolates into four phena. The main phenotypic traits to differentiate VAR strains from V. anguillarum were fermentation of arabinose and mannitol, indole and Voges-Proskauer reactions, gelatin and casein hydrolysis, hemolytic activity, growth at 37 and 4°C, and resistance to ampicillin. Serological analysis confirmed that phena I and II were composed mainly of strains of V. anguillarum, while phena III and IV included VAR strains. Excluding the reference strains, the typeable isolates belonged to serotypes O3 (15 strains), O4 (3 strains), and O5 (2 strains) of V. anguillarum. The infectivity trials showed that only 9 of a total of 24 strains tested displayed virulence for rainbow trout. Virulent strains (50% lethal dose ranging from 102 to 106 cells) included V. anguillarum strains belonging to serotypes O1 (one strain), O2 (one strain), O3 (three isolates), and O4 (one isolate) and only three strains of the VAR group. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of lipopolysaccharide and outer membrane proteins showed heterogeneity not only among the 10 V. anguillarum serotypes but also within the VAR group. Immunoblot assays demonstrated a close relationship among V. anguillarum strains from the same serotype, while strains from different serotypes were not antigenically related. The VAR strains did not share antigenic components with the serotypes of V. anguillarum tested (serotypes O1 to O5). Plasmids were detected in only 19 of the total of 59 strains. The majority of the strains carrying plasmids were grouped within phenon IV, in which plasmid bands of 27 and 36 MDa were found in all the isolates. No correlation between the plasmid content of VAR microorganisms and their phenotypic or virulence characteristics was observed. From these results it can be concluded that VAR strains associated with disease should be included together with V. anguillarum in the formulation of vaccines against vibriosis. Images PMID:16349042

  6. Detection and Localisation of the Abalone Probiotic Vibrio midae SY9 and Its Extracellular Protease, VmproA, within the Digestive Tract of the South African Abalone, Haliotis midae

    PubMed Central

    Huddy, Robert J.; Coyne, Vernon E.

    2014-01-01

    Probiotics have been widely reported to increase the growth rate of commercially important fish and shellfish by enhancing the digestion of ingested feed through the production of extracellular enzymes such as proteases and alginases. In order to investigate this further, the objective of this study was to localise the bacterial probiont Vibrio midae SY9 and one of the extracellular proteases it produces in the digestive tract of the South African abalone Haliotis midae. This was accomplished by inserting a promotorless gfp gene into the chromosome of the bacterium which was incorporated in an artificial, fishmeal-based abalone feed. In situ histological comparison of abalone fed either a basal diet or the basal diet supplemented with V. midae SY9::Tn10.52 using a cocktail of DNA probes to the gfp gene localised the probiont to the crop/stomach and intestinal regions of the H. midae digestive tract. Generally, the ingested probiotic bacterium occurred in association with feed and particulate matter within the crop/stomach and intestinal regions, as well as adhered to the wall of the crop/stomach. Histological immunohistochemical examination using polyclonal anti-VmproA antibodies localised an extracellular protease produced by V. midae SY9 to the H. midae crop/stomach and intestine where it appeared to be associated with feed and/or other particulate matter in the abalone gut. Thus the data suggests that V. midae SY9 colonises and/or adheres to the mucous lining of the abalone gut. Furthermore, the close association observed between the bacterium, its extracellular protease and ingested feed particles supports the theory that V. midae SY9 elevates in situ digestive enzyme levels and thus enhances feed digestion in farmed abalone. PMID:24466176

  7. Detection and localisation of the abalone probiotic Vibrio midae SY9 and its extracellular protease, VmproA, within the digestive tract of the South African abalone, Haliotis midae.

    PubMed

    Huddy, Robert J; Coyne, Vernon E

    2014-01-01

    Probiotics have been widely reported to increase the growth rate of commercially important fish and shellfish by enhancing the digestion of ingested feed through the production of extracellular enzymes such as proteases and alginases. In order to investigate this further, the objective of this study was to localise the bacterial probiont Vibrio midae SY9 and one of the extracellular proteases it produces in the digestive tract of the South African abalone Haliotis midae. This was accomplished by inserting a promotorless gfp gene into the chromosome of the bacterium which was incorporated in an artificial, fishmeal-based abalone feed. In situ histological comparison of abalone fed either a basal diet or the basal diet supplemented with V. midae SY9::Tn10.52 using a cocktail of DNA probes to the gfp gene localised the probiont to the crop/stomach and intestinal regions of the H. midae digestive tract. Generally, the ingested probiotic bacterium occurred in association with feed and particulate matter within the crop/stomach and intestinal regions, as well as adhered to the wall of the crop/stomach. Histological immunohistochemical examination using polyclonal anti-VmproA antibodies localised an extracellular protease produced by V. midae SY9 to the H. midae crop/stomach and intestine where it appeared to be associated with feed and/or other particulate matter in the abalone gut. Thus the data suggests that V. midae SY9 colonises and/or adheres to the mucous lining of the abalone gut. Furthermore, the close association observed between the bacterium, its extracellular protease and ingested feed particles supports the theory that V. midae SY9 elevates in situ digestive enzyme levels and thus enhances feed digestion in farmed abalone. PMID:24466176

  8. Putative Channel Components for the Fast-Rotating Sodium Driven Flagellar Motor of a Marine Bacterium

    Microsoft Academic Search

    YUKAKO ASAI; SEIJI KOJIMA; HARUKI KATO; NORIKO NISHIOKA; IKURO KAWAGISHI; MICHIO HOMMA

    1997-01-01

    The polar flagellum of Vibrio alginolyticus rotates remarkably fast (up to 1,700 revolutions per second) by using a motor driven by sodium ions. Two genes, motX and motY, for the sodium-driven flagellar motor have been identified in marine bacteria, Vibrio parahaemolyticus and V. alginolyticus. They have no similarity to the genes for proton-driven motors, motA and motB, whose products constitute

  9. A model for Vibrio cholerae colonization of the human intestine

    PubMed Central

    Spagnuolo, Anna Maria; DiRita, Victor; Kirschner, Denise

    2011-01-01

    Vibrio cholerae is a strict human pathogen that causes the disease cholera. It is an old-world pathogen that has re-emerged as a new threat since the early 1990s. V. cholerae colonizes the upper, small intestine where it produces a toxin that leads to watery diarrhea, characterizing the disease [36]. The dynamics of colonization by the bacteria of the intestines are largely unknown. Although a large initial infectious dose is required for infection, data suggests that only a smaller sub-population colonizes a portion of the small bowel leading to disease. There are many barriers to colonization in the intestines including peristalsis, fluid wash-out, viscosity of the mucus layer, and pH. We are interested in identifying the mechanisms that allow this sub-population of bacteria to survive and colonize the intestines when faced with these barriers. To elaborate the dynamics of V. cholerae infection, we have developed a mathematical model based on a convection-diffusion-reaction-swimming equation capturing bacterial dynamics coupled with Stokes equations governing fluid velocity where we developed a novel non-local boundary condition. Our results indicate that both host and bacterial factors contribute to bacterial density in the gut. Host factors include intestinal diffusion and convection rates while bacterial factors include adherence, motility and growth rates. This model can ultimately be used to test therapeutic strategies against V. cholerae. PMID:21903104

  10. ?-Hydroxyketone Synthesis and Sensing by Legionella and Vibrio

    PubMed Central

    Tiaden, André; Hilbi, Hubert

    2012-01-01

    Bacteria synthesize and sense low molecular weight signaling molecules, termed autoinducers, to measure their population density and community complexity. One class of autoinducers, the ?-hydroxyketones (AHKs), is produced and detected by the water-borne opportunistic pathogens Legionella pneumophila and Vibrio cholerae, which cause Legionnaires’ disease and cholera, respectively. The “Legionella quorum sensing” (lqs) or “cholera quorum sensing” (cqs) genes encode enzymes that produce and sense the AHK molecules “Legionella autoinducer-1” (LAI-1; 3-hydroxypentadecane-4-one) or cholera autoinducer-1 (CAI-1; 3-hydroxytridecane-4-one). AHK signaling regulates the virulence of L. pneumophila and V. cholerae, pathogen-host cell interactions, formation of biofilms or extracellular filaments, expression of a genomic “fitness island” and competence. Here, we outline the processes, wherein AHK signaling plays a role, and review recent insights into the function of proteins encoded by the lqs and cqs gene clusters. To this end, we will focus on the autoinducer synthases catalysing the biosynthesis of AHKs, on the cognate trans-membrane sensor kinases detecting the signals, and on components of the down-stream phosphorelay cascade that promote the transmission and integration of signaling events regulating gene expression. PMID:22736983

  11. Role of heme compounds and haptoglobin in Vibrio vulnificus pathogenicity.

    PubMed Central

    Helms, S D; Oliver, J D; Travis, J C

    1984-01-01

    An induced peritonitis model was employed in mice to determine whether heme-containing molecules enhance the lethality of infections by Vibrio vulnificus. The lethality of intraperitoneal (ip) inocula of the bacteria was increased by concurrent injections (ip) of hemoglobin, methemoglobin, or hematin, but not by myoglobin. Similar results were obtained in mice with phenylhydrazine-induced hemoglobinemia, in which after ip injections of V. vulnificus, a direct correlation between lethality and levels of plasma hemoglobin was observed. In vitro studies indicated that the growth of V. vulnificus, which was limited in an iron-poor medium, was enhanced by the addition of hemoglobin in a manner similar to an inorganic iron source, ferric ammonium citrate. These results suggest that V. vulnificus is capable of extracting iron from hemoglobin for use as a nutrilite, thereby promoting growth and increased lethality in the in vivo models. Further studies with human serum cultures demonstrated that the growth of V. vulnificus was not decreased when hemoglobin added to the serum was completely complexed with haptoglobin; these results are in opposition to those with cultures of Escherichia coli. These results are discussed relative to the capacity of V. vulnificus to produce fatal human infections. PMID:6746093

  12. Proteomic analysis of Vibrio cholerae outer membrane vesicles.

    PubMed

    Altindis, Emrah; Fu, Yang; Mekalanos, John J

    2014-04-15

    Outer membrane vesicles (OMVs) produced by Gram-negative bacteria provide an interesting research material for defining cell-envelope proteins without experimental cell disruption. OMVs are also promising immunogenic platforms and may play important roles in bacterial survival and pathogenesis. We used in-solution trypsin digestion coupled to mass spectrometry to identify 90 proteins present in OMVs of Vibrio cholerae when grown under conditions that activate the TCP pilus virulence regulatory protein (ToxT) virulence regulon. The ToxT expression profile and potential contribution to virulence of these proteins were assessed using ToxT and in vivo RNA-seq, Tn-seq, and cholera stool proteomic and other genome-wide data sets. Thirteen OMV-associated proteins appear to be essential for cell growth, and therefore may represent antibacterial drug targets. Another 12 nonessential OMV proteins, including DegP protease, were required for intestinal colonization in rabbits. Comparative proteomics of a degP mutant revealed the importance of DegP in the incorporation of nine proteins into OMVs, including ones involved in biofilm matrix formation and various substrates of the type II secretion system. Taken together, these results suggest that DegP plays an important role in determining the content of OMVs and also affects phenotypes such as intestinal colonization, proper function of the type II secretion system, and formation of biofilm matrix. PMID:24706774

  13. Characterization and distribution of the hemagglutinins produced by Vibrio cholerae.

    PubMed Central

    Hanne, L F; Finkelstein, R A

    1982-01-01

    Examination of the distribution of cell-associated and soluble hemagglutinins (HA) produced by Vibrio cholerae revealed the existence of four different HAs. A cell-associated mannose-sensitive HA (MSHA) was produced only by the El Tor biotype. This was evident with all El Tor strains examined. It appears to be responsible for the HA biotyping differentiation of El Tor from classical biotype V. cholerae. The MSHA had no apparent divalent ion requirement; it was inhibited by D-mannose and D-fructose; and it was active on all human (A, B, O) and all chicken erythrocytes tested. Spontaneous MSHA- mutants of El Tor strains were selected by cosedimentation of MSHA+ parent bacteria with erythrocytes. An L-fucose-sensitive HA was detected transiently in early log-phase growth with two of the four classical strains examined and with MSHA- mutants of El Tor biotype strains 3083, 26-3, and 17. MSHA- mutants also expressed another cell-associated HA in late log-phase cultures. A "soluble" HA was detected in late log-phase cultures of all strains tested. This HA was not inhibitable by any sugars tested; it required CA2+ ions for maximum activity; and it was active on some chicken erythrocytes but not others. PMID:7076294

  14. Predation Response of Vibrio fischeri Biofilms to Bacterivorus Protists

    PubMed Central

    Chavez-Dozal, Alba; Gorman, Clayton; Erken, Martina; Steinberg, Peter D.; McDougald, Diane

    2013-01-01

    Vibrio fischeri proliferates in a sessile, stable community known as a biofilm, which is one alternative survival strategy of its life cycle. Although this survival strategy provides adequate protection from abiotic factors, marine biofilms are still susceptible to grazing by bacteria-consuming protozoa. Subsequently, grazing pressure can be controlled by certain defense mechanisms that confer higher biofilm antipredator fitness. In the present work, we hypothesized that V. fischeri exhibits an antipredator fitness behavior while forming biofilms. Different predators representing commonly found species in aquatic populations were examined, including the flagellates Rhynchomonas nasuta and Neobodo designis (early biofilm feeders) and the ciliate Tetrahymena pyriformis (late biofilm grazer). V. fischeri biofilms included isolates from both seawater and squid hosts (Euprymna and Sepiola species). Our results demonstrate inhibition of predation by biofilms, specifically, isolates from seawater. Additionally, antiprotozoan behavior was observed to be higher in late biofilms, particularly toward the ciliate T. pyriformis; however, inhibitory effects were found to be widespread among all isolates tested. These results provide an alternative explanation for the adaptive advantage and persistence of V. fischeri biofilms and provide an important contribution to the understanding of defensive mechanisms that exist in the out-of-host environment. PMID:23144127

  15. [The in vitro action of plants on Vibrio cholerae].

    PubMed

    Guevara, J M; Chumpitaz, J; Valencia, E

    1994-01-01

    Natural products of several plants, according to the geographic location, are used by Peruvian people in the popular treatment of diarrhea, with good success. When cholerae cases appeared in Peru, we were interested to know the "in vitro" effect against Vibrio cholerae 01, of these useful plants to treat diarrhea. The following plants were tested: Cichorium intybus, Althaea officinalis, Psorela glandulosa, Geranium maculatum, Punica granatum, Malus sativa, Cydonia oblonga, Chenopodium ambrosoides, Krameria triandria, Tea chinensis, Daucus carota, Persea gratissima, Psidium guayaba and Lippia dulcis. Decoction or infusion of the plants were used in the "in vitro" experiments. The following plants showed no "in vitro" effect against V. cholerae: Cichorium intybus, Althaea officinalis, Psorela glandulosa, Geranium maculatum, Chenopodium ambrosoides, Krameria triandria, Psidium guayaba, Lippia dulcis and Daucus carota. Decoction of Malus sativa and Cydenia oblonga showed bactericidal effect for their acidity and stone avocado (Persea gratissima) a late bactericidal effect. Tea infusión and the decoction of Punica granatum peel, showed the best bactericidal effect and we suggest to use them as to stop cholera spreading. PMID:8018898

  16. Proteomic analysis of Vibrio cholerae outer membrane vesicles

    PubMed Central

    Altindis, Emrah; Fu, Yang; Mekalanos, John J.

    2014-01-01

    Outer membrane vesicles (OMVs) produced by Gram-negative bacteria provide an interesting research material for defining cell-envelope proteins without experimental cell disruption. OMVs are also promising immunogenic platforms and may play important roles in bacterial survival and pathogenesis. We used in-solution trypsin digestion coupled to mass spectrometry to identify 90 proteins present in OMVs of Vibrio cholerae when grown under conditions that activate the TCP pilus virulence regulatory protein (ToxT) virulence regulon. The ToxT expression profile and potential contribution to virulence of these proteins were assessed using ToxT and in vivo RNA-seq, Tn-seq, and cholera stool proteomic and other genome-wide data sets. Thirteen OMV-associated proteins appear to be essential for cell growth, and therefore may represent antibacterial drug targets. Another 12 nonessential OMV proteins, including DegP protease, were required for intestinal colonization in rabbits. Comparative proteomics of a degP mutant revealed the importance of DegP in the incorporation of nine proteins into OMVs, including ones involved in biofilm matrix formation and various substrates of the type II secretion system. Taken together, these results suggest that DegP plays an important role in determining the content of OMVs and also affects phenotypes such as intestinal colonization, proper function of the type II secretion system, and formation of biofilm matrix. PMID:24706774

  17. Detection, Isolation, and Identification of Vibrio cholerae from the Environment

    PubMed Central

    Huq, Anwar; Haley, Bradd J.; Taviani, Elisa; Chen, Arlene; Hasan, Nur A.; Colwell, Rita R.

    2012-01-01

    Recent molecular advances in microbiology have greatly improved the detection of bacterial pathogens in the environment. Improvement and a downward trend in the cost of molecular detection methods have contributed to increased frequency of detection of pathogenic microorganisms where traditional culture-based detection methods have failed. Culture methods also have been greatly improved and the confluence of the two suites of methods provides a powerful tool for detection, isolation, and characterization of pathogens. While molecular detection provides data on the presence and type of pathogens, culturing methods allow a researcher to preserve the organism of interest for “–omics” studies, such as genomic, metabolomic, secretomic, and transcriptomic analysis, which are rapidly becoming more affordable. This has yielded a clearer understanding of the ecology and epidemiology of microorganisms that cause disease. Specifically, important advances have been made over the past several years on isolation, detection, and identification of Vibrio cholerae, the causative agent of cholera in humans. In this unit, we present commonly accepted methods for isolation, detection, and characterization of V. cholerae, providing more extensive knowledge of the ecology and epidemiology of this organism. This unit has been fully revised and updated from the earlier unit (Huq, Grim et al. 2006) with the latest knowledge and additional information not previously included. We have also taken into account of cost of reagents and equipment that may be prohibitive for many researchers and have, therefore, included protocols for all laboratories, including those with limited resources, likely to be located in regions of cholera endemicity. PMID:22875567

  18. Genetic characterization of trh positive Vibrio spp. isolated from Norway.

    PubMed

    Ellingsen, Anette B; Olsen, Jaran S; Granum, Per E; Rørvik, Liv M; González-Escalona, Narjol

    2013-01-01

    The thermostable direct hemolysin (TDH) and/or TDH-related hemolysin (TRH) genes are carried by most virulent Vibrio parahaemolyticus serovars. In Norway, trh+ V. parahaemolyticus constitute 4.4 and 4.5% of the total number of V. parahaemolyticus isolated from blue mussel (Mytilus edulis) and water, respectively. The trh gene is located in a region close to the gene cluster for urease production (ure). This region was characterized in V. parahaemolyticus strain TH3996 and it was found that a nickel transport operon (nik) was located between the first gene (ureR) and the rest of the ure cluster genes. The organization of the trh-ureR-nik-ure gene cluster in the Norwegian trh+ isolates was unknown. In this study, we explore the gene organization within the trh-ureR-nik-ure cluster for these isolates. PCR analyses revealed that the genes within the trh-ureR-nik-ure gene cluster of Norwegian trh+ isolates were organized in a similar fashion as reported previously for TH33996. Additionally, the phylogenetic relationship among these trh+ isolates was investigated using Multilocus Sequence Typing (MLST). Analysis by MLST or ureR-trh sequences generated two different phylogenetic trees for the same strains analyzed, suggesting that ureR-trh genes have been acquired at different times in Norwegian V. parahaemolyticus isolates. MLST results revealed that some pathogenic and non-pathogenic V. parahaemolyticus isolates in Norway appear to be highly genetically related. PMID:24400227

  19. Genetic characterization of trh positive Vibrio spp. isolated from Norway

    PubMed Central

    Ellingsen, Anette B.; Olsen, Jaran S.; Granum, Per E.; Rørvik, Liv M.; González-Escalona, Narjol

    2013-01-01

    The thermostable direct hemolysin (TDH) and/or TDH-related hemolysin (TRH) genes are carried by most virulent Vibrio parahaemolyticus serovars. In Norway, trh+ V. parahaemolyticus constitute 4.4 and 4.5% of the total number of V. parahaemolyticus isolated from blue mussel (Mytilus edulis) and water, respectively. The trh gene is located in a region close to the gene cluster for urease production (ure). This region was characterized in V. parahaemolyticus strain TH3996 and it was found that a nickel transport operon (nik) was located between the first gene (ureR) and the rest of the ure cluster genes. The organization of the trh-ureR-nik-ure gene cluster in the Norwegian trh+ isolates was unknown. In this study, we explore the gene organization within the trh-ureR-nik-ure cluster for these isolates. PCR analyses revealed that the genes within the trh-ureR-nik-ure gene cluster of Norwegian trh+ isolates were organized in a similar fashion as reported previously for TH33996. Additionally, the phylogenetic relationship among these trh+ isolates was investigated using Multilocus Sequence Typing (MLST). Analysis by MLST or ureR-trh sequences generated two different phylogenetic trees for the same strains analyzed, suggesting that ureR-trh genes have been acquired at different times in Norwegian V. parahaemolyticus isolates. MLST results revealed that some pathogenic and non-pathogenic V. parahaemolyticus isolates in Norway appear to be highly genetically related. PMID:24400227

  20. Faecal contamination indicators, Salmonella, Vibrio and Aeromonas in water used for the irrigation of agricultural products.

    PubMed Central

    Pianietti, A.; Sabatini, L.; Bruscolini, F.; Chiaverini, F.; Cecchetti, G.

    2004-01-01

    The faecal contamination indicators (total coliforms, faecal coliforms, Escherichia coli, enterococci) and the genera Salmonella, Vibrio, Aeromonas were investigated in water samples used for irrigation. During 4 months, 52 samples were taken. The methods used were: multiple tube fermentation method for faecal contamination indicators and membrane filtration techniques for salmonella, aeromonas and vibrio. Two samples were positive for Salmonella spp., fourteen for Aeromonas spp. and no samples for Vibrio spp. No correlation was found between aeromonas and the indicators of faecal contamination. Regarding Aeromonas spp., 21.6% of the strains were adhesive and 12.6% cytotoxic: this confirms the possible role of aeromonas in human pathologies. These results are important to determine the quality of irrigation water in relation to human health. In fact, the spray or sprinkler irrigation produces bioaerosol, which can contaminate the crops that are likely to be eaten uncooked. In addition, the flood or furrow irrigation represents a risk to field workers. PMID:15061497

  1. Challenge of New Zealand Greenshell mussel Perna canaliculus larvae using two Vibrio pathogens: a hatchery study.

    PubMed

    Kesarcodi-Watson, Aditya; Kaspar, Heinrich; Lategan, M Josie; Gibson, Lewis F

    2009-09-01

    Bacterial diseases remain a large problem in aquaculture hatcheries. The successful design and implementation of protective measures in the hatchery depends on an understanding of the dynamics of the infection process. Developing an in situ experimental protocol for pathogen challenge is therefore of paramount importance. Here, we demonstrated the minimum effective pathogenic dose (MEPD) of Vibrio splendidus (10(5) CFU ml(-1)) and a Vibrio coralliilyticus/neptunius-like isolate, Vibrio sp. DO1 (10(6) CFU ml(-1)), for New Zealand Greenshell mussel (GSM, Perna canaliculus) larvae during hatchery production. In a flow-through water hatchery system, larvae given 1 to 2 h of static water exposure to these pathogen doses showed respective average cumulative mortalities of 58 and 69% on the fourth day following pathogen exposure. After the 1 to 2 h static exposure, larvae were returned to flow-through water. Larvae exposed to a dosage one order of magnitude greater than the MEPD had higher mortalities of 73 and 96% for V. splendidus and Vibrio sp. DO1 respectively. These 4 levels of mortality were significantly greater than those of the non-exposed control larvae which respectively averaged 23 and 35% in experiments involving V. splendidus and Vibrio sp. DO1. Experiments were repeated 4 times to confirm reproducibility. After pathogen exposure, pathogens were detected in the larvae and tank water of treatments with dosages of > or =10(5) CFU ml(-1) (V. splendidus) and 10(6) CFU ml(-1) (Vibrio sp. DO1), but not in treatments with lower pathogen dosages. The challenge protocols are reproducible and provide an opportunity to assess measures for the protection of GSM larvae against infection in the hatchery environment. PMID:19899345

  2. Original Article Cloning of Multidrug-Resistant Genes from Vibrio cholerae Non-O1

    E-print Network

    Anowara Begum; Teruo Kuroda; Tomofusa Tsuchiya

    2006-01-01

    Both clinical and environmental multidrug-resistant strains of Vibrio cholerae (O1 and non-O1) have been reported from different parts of the world. In this study, we have cloned twenty-five genes associated drug resistance in Vibrio cholerae non-O1 NCTC4716 using shotgun cloning method. All of the cloned genes were introduced and expressed in a drug hypersusceptible host Escherichia coli KAM32. We observed elevated minimum inhibitory concentration (MIC) of various antimicrobial agents such as fluoroquinolones, aminoglycosides, ethidium bromide and others in all transformants.

  3. Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment, and cultured oysters in the Chesapeake Bay, MD, USA.

    PubMed

    Shaw, Kristi S; Jacobs, John M; Crump, Byron C

    2014-01-01

    To determine if a storm event (i.e., high winds, large volumes of precipitation) could alter concentrations of Vibrio vulnificus and V. parahaemolyticus in aquacultured oysters (Crassostrea virginica) and associated surface water and sediment, this study followed a sampling timeline before and after Hurricane Irene impacted the Chesapeake Bay estuary in late August 2011. Aquacultured oysters were sampled from two levels in the water column: surface (0.3 m) and near-bottom (just above the sediment). Concentrations of each Vibrio spp. and associated virulence genes were measured in oysters with a combination of real-time PCR and most probable number (MPN) enrichment methods, and in sediment and surface water with real-time PCR. While concentration shifts of each Vibrio species were apparent post-storm, statistical tests indicated no significant change in concentration for either Vibrio species by location (surface or near bottom oysters) or date sampled (oyster tissue, surface water, and sediment concentrations). V. vulnificus in oyster tissue was correlated with total suspended solids (r = 0.41, P = 0.04), and V. vulnificus in sediment was correlated with secchi depth (r = -0.93, P <0.01), salinity (r = -0.46, P = 0.02), tidal height (r = -0.45, P = 0.03), and surface water V. vulnificus (r = 0.98, P <0.01). V. parahaemolyticus in oyster tissue did not correlate with environmental measurements, but V. parahaemolyticus in sediment and surface water correlated with several measurements including secchi depth [r = -0.48, P = 0.02 (sediment); r = -0.97, P <0.01 (surface water)] and tidal height [r = -0.96, P <0.01 (sediment), r = -0.59, P <0.01 (surface water)]. The concentrations of Vibrio spp. were higher in oysters relative to other studies (average V. vulnificus 4 × 10(5) MPN g(-1), V. parahaemolyticus 1 × 10(5) MPN g(-1)), and virulence-associated genes were detected in most oyster samples. This study provides a first estimate of storm-related Vibrio density changes in oyster tissues, sediment, and surface water at an aquaculture facility in the Chesapeake Bay. PMID:24847319

  4. Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment, and cultured oysters in the Chesapeake Bay, MD, USA

    PubMed Central

    Shaw, Kristi S.; Jacobs, John M.; Crump, Byron C.

    2013-01-01

    To determine if a storm event (i.e., high winds, large volumes of precipitation) could alter concentrations of Vibrio vulnificus and V. parahaemolyticus in aquacultured oysters (Crassostrea virginica) and associated surface water and sediment, this study followed a sampling timeline before and after Hurricane Irene impacted the Chesapeake Bay estuary in late August 2011. Aquacultured oysters were sampled from two levels in the water column: surface (0.3 m) and near-bottom (just above the sediment). Concentrations of each Vibrio spp. and associated virulence genes were measured in oysters with a combination of real-time PCR and most probable number (MPN) enrichment methods, and in sediment and surface water with real-time PCR. While concentration shifts of each Vibrio species were apparent post-storm, statistical tests indicated no significant change in concentration for either Vibrio species by location (surface or near bottom oysters) or date sampled (oyster tissue, surface water, and sediment concentrations). V. vulnificus in oyster tissue was correlated with total suspended solids (r = 0.41, P = 0.04), and V. vulnificus in sediment was correlated with secchi depth (r = -0.93, P <0.01), salinity (r = -0.46, P = 0.02), tidal height (r = -0.45, P = 0.03), and surface water V. vulnificus (r = 0.98, P <0.01). V. parahaemolyticus in oyster tissue did not correlate with environmental measurements, but V. parahaemolyticus in sediment and surface water correlated with several measurements including secchi depth [r = -0.48, P = 0.02 (sediment); r = -0.97, P <0.01 (surface water)] and tidal height [r = -0.96, P <0.01 (sediment), r = -0.59, P <0.01 (surface water)]. The concentrations of Vibrio spp. were higher in oysters relative to other studies (average V. vulnificus 4 × 105 MPN g-1, V. parahaemolyticus 1 × 105 MPN g-1), and virulence-associated genes were detected in most oyster samples. This study provides a first estimate of storm-related Vibrio density changes in oyster tissues, sediment, and surface water at an aquaculture facility in the Chesapeake Bay. PMID:24847319

  5. A Streamlined Strategy for Biohydrogen Production with an Alkaliphilic Bacterium

    SciTech Connect

    Elias, Dwayne A [ORNL; Wall, Judy D. [University of Missouri; Mormile, Dr. Melanie R. [Missouri University of Science and Technology; Begemann, Matthew B [University of Wisconsin, Madison

    2012-01-01

    Biofuels are anticipated to enable a shift from fossil fuels for renewable transportation and manufacturing fuels, with biohydrogen considered attractive since it could offer the largest reduction of global carbon budgets. Currently, biohydrogen production remains inefficient and heavily fossil fuel-dependent. However, bacteria using alkali-treated biomass could streamline biofuel production while reducing costs and fossil fuel needs. An alkaliphilic bacterium, Halanaerobium strain sapolanicus, is described that is capable of biohydrogen production at levels rivaling neutrophilic strains, but at pH 11 and hypersaline conditions. H. sapolanicus ferments a variety of 5- and 6- carbon sugars derived from hemicellulose and cellulose including cellobiose, and forms the end products hydrogen and acetate. Further, it can also produce biohydrogen from switchgrass and straw pretreated at temperatures far lower than any previously reported and in solutions compatible with growth. Hence, this bacterium can potentially increase the efficiency and efficacy of biohydrogen production from renewable biomass resources.

  6. Isolation of a bacterium capable of degrading peanut hull lignin

    SciTech Connect

    Kerr, T.A.; Kerr, R.D.; Benner, R.

    1983-11-01

    Thirty-seven bacterial strains capable of degrading peanut hull lignin were isolated by using four types of lignin preparations and hot-water-extracted peanut hulls. One of the isolates, tentatively identified as Arthrobacter species, was capable of utilizing all four lignin preparations as well as extracted peanut hulls as a sole source of carbon. The bacterium was also capable of degrading specifically labeled (/sup 14/C) lignin-labeled lignocellulose and (/sup 14/C)cellulose-labeled lignocellulose from the cordgrass Spartina alterniflora and could also degrade (/sup 14/C) Kraft lignin from slash pine. After 10 days of incubation with (/sup 14/C) cellulose-labeled lignocellulose or (/sup 14/C) lignin-labeled lignocellulose from S. alterniflora, the bacterium mineralized 6.5% of the polysaccharide component and 2.9% of the lignin component. (Refs. 24).

  7. Trichloroethylene Biodegradation by a Methane-Oxidizing Bacterium

    PubMed Central

    Little, C. Deane; Palumbo, Anthony V.; Herbes, Stephen E.; Lidstrom, Mary E.; Tyndall, Richard L.; Gilmer, Penny J.

    1988-01-01

    Trichloroethylene (TCE), a common groundwater contaminant, is a suspected carcinogen that is highly resistant to aerobic biodegradation. An aerobic, methane-oxidizing bacterium was isolated that degrades TCE in pure culture at concentrations commonly observed in contaminated groundwater. Strain 46-1, a type I methanotrophic bacterium, degraded TCE if grown on methane or methanol, producing CO2 and water-soluble products. Gas chromatography and 14C radiotracer techniques were used to determine the rate, methane dependence, and mechanism of TCE biodegradation. TCE biodegradation by strain 46-1 appears to be a cometabolic process that occurs when the organism is actively metabolizing a suitable growth substrate such as methane or methanol. It is proposed that TCE biodegradation by methanotrophs occurs by formation of TCE epoxide, which breaks down spontaneously in water to form dichloroacetic and glyoxylic acids and one-carbon products. Images PMID:16347616

  8. Isolation of a Bacterium Capable of Degrading Peanut Hull Lignin

    PubMed Central

    Kerr, Thomas J.; Kerr, Robert D.; Benner, Ronald

    1983-01-01

    Thirty-seven bacterial strains capable of degrading peanut hull lignin were isolated by using four types of lignin preparations and hot-water-extracted peanut hulls. One of the isolates, tentatively identified as Arthrobacter sp., was capable of utilizing all four lignin preparations as well as extracted peanut hulls as a sole source of carbon. The bacterium was also capable of degrading specifically labeled [14C]lignin-labeled lignocellulose and [14C]cellulose-labeled lignocellulose from the cordgrass Spartina alterniflora and could also degrade [14C]Kraft lignin from slash pine. After 10 days of incubation with [14C]cellulose-labeled lignocellulose or [14C]lignin-labeled lignocellulose from S. alterniflora, the bacterium mineralized 6.5% of the polysaccharide component and 2.9% of the lignin component. Images PMID:16346424

  9. Molecular pathogenesis of the obligate intracellular bacterium Coxiella burnetii

    PubMed Central

    van Schaik, Erin J.; Chen, Chen; Mertens, Katja; Weber, Mary M.; Samuel, James E.

    2014-01-01

    The agent of Q fever, Coxiella burnetii, is an obligate intracellular bacterium that causes acute and chronic infections. The study of C. burnetii pathogenesis has benefited from two recent fundamental advances: improved genetic tools and the ability to grow the bacterium in extracellular media. In this Review, we describe how these recent advances have improved our understanding of C. burnetii invasion and host cell modulation, including the formation of replication-permissive Coxiella-containing vacuoles. Furthermore, we describe the Dot/Icm (defect in organelle trafficking/intracellular multiplication) system, which is used by C. burnetii to secrete a range of effector proteins into the host cell, and we discuss the role of these effectors in remodelling the host cell. PMID:23797173

  10. Whole-cell arsenite biosensor using photosynthetic bacterium Rhodovulum sulfidophilum

    Microsoft Academic Search

    Hiroyuki Fujimoto; Masato Wakabayashi; Hidenori Yamashiro; Isamu Maeda; Katsuhiro Isoda; Masuo Kondoh; Masaya Kawase; Hitoshi Miyasaka; Kiyohito Yagi

    2006-01-01

    An arsenite biosensor plasmid was constructed in Escherichia coli by inserting the operator\\/promoter region of the ars operon and the arsR gene from E. coli and the crtA gene, which is responsible for carotenoid synthesis in the photosynthetic bacterium, Rhodovulum sulfidophilum, into the broad-host-range plasmid vector, pRK415. The biosensor plasmid, pSENSE-As, was introduced into a crtA-deleted mutant strain of R.

  11. Thermostable purified endoglucanase from thermophilic bacterium acidothermus cellulolyticus

    DOEpatents

    Tucker, Melvin P. (Lakewood, CO); Grohmann, Karel (Littleton, CO); Himmel, Michael E. (Littleton, CO); Mohagheghi, Ali (Golden, CO)

    1992-01-01

    A substantially purified high molecular weight cellulase enzyme having a molecular weight of between about 156,000 to about 203,400 daltons isolated from the bacterium Acidothermus cellulolyticus (ATCC 43068) and a method of producing it are disclosed. The enzyme is water soluble, possesses both C.sub.1 and C.sub.x types of enzymatic activity, has a high degree of stability toward heat and exhibits both a high optimum temperature activity and high inactivation characteristics.

  12. Translational system of the hydrogen-oxidizing bacterium Alcaligenes eutrophus

    Microsoft Academic Search

    K. Mikulík; I. Janda; A. Jirá?ová; J. Ma?as; G. A. Zavarzin

    1987-01-01

    Some structural and functional properties of ribosomes from the hydrogen-oxidizing bacterium Alcaligenes eutrophus were studied in order to investigate the background of expression of genetic information at the translational level. Ribosomal proteins from 30S subunits of A. eutrophus H16 were separated by two-dimensional gel electrophoresis into 21 spots, those from 50S subunits into 32 spots. While electrophoretic mobilities of several

  13. Genome of the Bacterium Streptococcus pneumoniae Strain R6

    Microsoft Academic Search

    JOANN HOSKINS; WILLIAM E. ALBORN; JEFFREY ARNOLD; LARRY C. BLASZCZAK; STANLEY BURGETT; BRADLEY S. DEHOFF; SHAWN T. ESTREM; LORI FRITZ; DONG-JING FU; WENDY FULLER; CHAD GERINGER; RAYMOND GILMOUR; JENNIFER S. GLASS; HAMID KHOJA; ANGELIKA R. KRAFT; ROBERT E. LAGACE; DONALD J. LEBLANC; LINDA N. LEE; ELLIOT J. LEFKOWITZ; JIN LU; PATTI MATSUSHIMA; SCOTT M. MCAHREN; MARGARET MCHENNEY; KEVIN MCLEASTER; CHRISTOPHER W. MUNDY; THALIA I. NICAS; FRANKLIN H. NORRIS; M. O'Gara; R. B. Peery; G. T. Robertson; P. Rockey; P.-M. Sun; M. E. Winkler; Y. Yang; M. Young-Bellido; G. Zhao; C. A. Zook; R. H. Baltz; S. R. Jaskunas; P. R. Rosteck; PAUL L. SKATRUD; JOHN I. GLASS

    2001-01-01

    Streptococcus pneumoniae is among the most significant causes of bacterial disease in humans. Here we report the 2,038,615-bp genomic sequence of the gram-positive bacterium S. pneumoniae R6. Because the R6 strain is avirulent and, more importantly, because it is readily transformed with DNA from homologous species and many heterologous species, it is the principal platform for investigation of the biology

  14. A physical map of the hyperthermophilic bacterium Aquifex pyrophilus chromosome.

    PubMed Central

    Shao, Z; Mages, W; Schmitt, R

    1994-01-01

    A genomic map of the hyperthermophilic hydrogen-oxidizing bacterium Aquifex pyrophilus was established with NotI (GC/GGCCGC), SpeI (A/CTAGT), and XbaI (T/CTAGA). Linking clones and cross-hybridization of restriction fragments revealed a single circular chromosome of 1.6 Mbp. A single flagellin gene and six rRNA gene units were located on this map by Southern hybridization. Images PMID:7961434

  15. A gas vesiculate planktonic strain of the purple non-sulfur bacterium Rhodoferax antarcticus isolated from Lake Fryxell, Dry Valleys, Antarctica.

    PubMed

    Jung, Deborah O; Achenbach, Laurie A; Karr, Elizabeth A; Takaichi, Shinichi; Madigan, Michael T

    2004-10-01

    A moderately psychrophilic purple non-sulfur bacterium, Rhodoferax antarcticus strain Fryx1, is described. Strain Fryx1 was isolated from the water column under the ice of the permanently frozen Lake Fryxell, Antarctica. Cells of Fryx1 are long thin rods and contain gas vesicles, the first report of such structures in purple non-sulfur bacteria. Gas vesicles are clustered at 2-4 sites per cell. Surprisingly, the 16S rRNA gene sequence of strain Fryx1 is nearly identical to that of Rfx. antarcticus strain AB, a short, vibrio-shaped phototroph isolated from an Antarctic microbial mat. Although showing physiological parallels, strains AB and Fryx1 differ distinctly in their morphology and absorption spectra. DNA-DNA hybridization shows that the genomes of strains AB and Fryx1 are highly related, yet distinct. We conclude that although strains AB and Fryx1 may indeed be the same species, their ecologies are quite different. Unlike strain AB, strain Fryx1 has adapted to a planktonic existence in the nearly freezing water column of Lake Fryxell. PMID:15340780

  16. The novel catabolic pathway of 3,6-anhydro-L-galactose, the main component of red macroalgae, in a marine bacterium.

    PubMed

    Yun, Eun Ju; Lee, Saeyoung; Kim, Hee Taek; Pelton, Jeffrey G; Kim, Sooah; Ko, Hyeok-Jin; Choi, In-Geol; Kim, Kyoung Heon

    2014-08-26

    The catabolic fate of the major monomeric sugar of red macroalgae, 3,6-anhydro-L-galactose (AHG), is completely unknown in any organisms. AHG is not catabolized by ordinary fermentative microorganisms, and it hampers the utilization of red macroalgae as renewable biomass for biofuel and chemical production. In this study, metabolite and transcriptomic analyses of Vibrio sp., a marine bacterium capable of catabolizing AHG as a sole carbon source, revealed two key metabolic intermediates of AHG, 3,6-anhydrogalactonate (AHGA) and 2-keto-3-deoxy-galactonate; the corresponding genes were verified in vitro enzymatic reactions using their recombinant proteins. Oxidation by an NADP(+) -dependent AHG dehydrogenase and isomerization by an AHGA cycloisomerase are the two key AHG metabolic processes. This newly discovered metabolic route was verified in vivo by demonstrating the growth of Escherichia coli harbouring the genes of these two enzymes on AHG as a sole carbon source. Also, the introduction of only these two enzymes into an ethanologenic E.?coli strain increased the ethanol production in E.?coli by fermenting both AHG and galactose in an agarose hydrolysate. These findings provide not only insights for the evolutionary adaptation of a central metabolic pathway to utilize uncommon substrates in microbes, but also a metabolic design principle for bioconversion of red macroalgal biomass into biofuels or industrial chemicals. PMID:25156229

  17. Abundance and distribution of Vibrio cholerae, V. parahaemolyticus, and V. vulnificus following a major freshwater intrusion into the Mississippi Sound.

    PubMed

    Griffitt, Kimberly J; Grimes, D Jay

    2013-04-01

    In response to a major influx of freshwater to the Mississippi Sound following the opening of the Bonnet Carre Spillway, water samples were collected from three sites along the Mississippi shoreline to assess the impact of altered salinity on three pathogenic Vibrio species. Salinity readings across the affected area during the 2011 sample period ranged from 1.4 to 12.9 ppt (mean = 7.0) and for the 2012 sample period from 14.1 to 23.6 ppt (mean = 19.8). Analyses of the data collected in 2011 showed a reduction in densities of Vibrio parahaemolyticus and Vibrio vulnificus with a concurrent increase of Vibrio cholerae numbers, with V. cholerae becoming the only Vibrio detected once salinity readings dropped to 6 ppt. Follow-up samples taken in 2012 after recovery of the salinity in the sound showed that the relative densities of the three pathogenic vibrios had reverted back to normal levels. This study shows that although the spillway was open but a few weeks and the effects were therefore time limited, the Mississippi River water had a profound, if temporary, effect on Vibrio ecology in the Mississippi Sound. PMID:23494573

  18. Infaunal Burrows Are Enrichment Zones for Vibrio parahaemolyticus?†

    PubMed Central

    Gamble, Megan D.; Lovell, Charles R.

    2011-01-01

    Vibrio parahaemolyticus, a species that includes strains known to be pathogenic in humans, and other Vibrionaceae are common, naturally occurring bacteria in coastal environments. Understanding the ecology and transport of these organisms within estuarine systems is fundamental to predicting outbreaks of pathogenic strains. Infaunal burrows serve as conduits for increased transport of tidal waters and V. parahaemolyticus cells by providing large open channels from the sediment to salt marsh tidal creeks. An extensive seasonal study was conducted at the North Inlet Estuary in Georgetown, SC, to quantify Vibrionaceae and specifically V. parahaemolyticus bacteria in tidal water, fiddler crab (Uca pugilator, Uca pugnax) burrow water, and interstitial pore water. Numbers of V. parahaemolyticus bacteria were significantly higher within burrow waters (4,875 CFU ml?1) than in creek water (193 CFU ml?1) and interstitial pore water (128 CFU ml?1), demonstrating that infaunal burrows are sites of V. parahaemolyticus enrichment. A strong seasonal trend of increased abundances of Vibrionaceae and V. parahaemolyticus organisms during the warmer months of May through September was observed. Multilocus sequence typing (MLST) analysis of isolates presumed to be V. parahaemolyticus from creek water, pore water, and burrow water identified substantial strain-level genetic variability among V. parahaemolyticus bacteria. Analysis of carbon substrate utilization capabilities of organisms presumed to be V. parahaemolyticus also indicated physiological diversity within this clade, which helps to explain the broad distribution of these strains within the estuary. These burrows are “hot spots” of Vibrionaceae and V. parahaemolyticus cell numbers and strain diversity and represent an important microhabitat. PMID:21478307

  19. Features governing symbiont persistence in the squid-vibrio association

    PubMed Central

    Koch, Eric J.; Miyashiro, Tim; McFall-Ngai, Margaret J.; Ruby, Edward G.

    2013-01-01

    Experimental studies of the interaction between host and symbiont in a maturing symbiotic organ have presented a challenge for most animal-bacterial associations. Advances in the rearing of the host squid Euprymna scolopes have enabled us to explore the relationship between a defect in symbiont light production and late-stage development (e.g., symbiont persistence and tissue morphogenesis) by experimental colonization with specific strains of the symbiont Vibrio fischeri. During the first four weeks post-inoculation of juvenile squid, the population of wild-type V. fischeri increased 100-fold; in contrast, a strain defective in light production (?lux) colonized normally the first day, but exhibited an exponential decline to undetectable levels over subsequent weeks. Co-colonization of organs by both strains affected neither the trajectory of colonization by wild type, nor the decline of ?lux levels. Uninfected animals retained the ability to be colonized for at least two weeks post-hatch. However, once colonized by the wild-type strain for 5 days, a subsequent experimentally induced loss of the symbionts could not be followed by a successful recolonization, indicating the host’s entry into a refractory state. However, animals colonized by the ?lux before the loss of their symbionts were receptive to recolonization. Analyses of animals colonized with either a wild-type or a ?lux strain revealed slight, if any, differences in the developmental regression of the ciliated light-organ tissues that facilitate the colonization process. Thus, some other feature(s) of the ?lux strain’s defect also may be responsible for its inability to persist, and its failure to induce a refractory state in the host. PMID:24118200

  20. Vibrio cholerae Classical Biotype Strains Reveal Distinct Signatures in Mexico

    PubMed Central

    Alam, Munirul; Islam, M. Tarequl; Rashed, Shah Manzur; Johura, Fatema-tuz; Bhuiyan, Nurul A.; Delgado, Gabriela; Morales, Rosario; Mendez, Jose Luis; Navarro, Armando; Watanabe, Haruo; Hasan, Nur-A; Colwell, Rita R.

    2012-01-01

    Vibrio cholerae O1 classical (CL) biotype caused the fifth and sixth pandemics, and probably the earlier cholera pandemics, before the El Tor (ET) biotype initiated the seventh pandemic in Asia in the 1970s by completely displacing the CL biotype. Although the CL biotype was thought to be extinct in Asia and although it had never been reported from Latin America, V. cholerae CL and ET biotypes, including a hybrid ET, were found associated with areas of cholera endemicity in Mexico between 1991 and 1997. In this study, CL biotype strains isolated from areas of cholera endemicity in Mexico between 1983 and 1997 were characterized in terms of major phenotypic and genetic traits and compared with CL biotype strains isolated in Bangladesh between 1962 and 1989. According to sero- and biotyping data, all V. cholerae strains tested had the major phenotypic and genotypic characteristics specific for the CL biotype. Antibiograms revealed the majority of the Bangladeshi strains to be resistant to trimethoprim-sulfamethoxazole, furazolidone, ampicillin, and gentamicin, while the Mexican strains were sensitive to all of these drugs, as well as to ciprofloxacin, erythromycin, and tetracycline. Pulsed-field gel electrophoresis (PFGE) of NotI-digested genomic DNA revealed characteristic banding patterns for all of the CL biotype strains although the Mexican strains differed from the Bangladeshi strains in 1 to 2 DNA bands. The difference was subtle but consistent, as confirmed by the subclustering patterns in the PFGE-based dendrogram, and can serve as a regional signature, suggesting the pre-1991 existence and evolution of the CL biotype strains in the Americas, independent from Asia. PMID:22518867

  1. Complete Topology of the RNF Complex from Vibrio cholerae.

    PubMed

    Hreha, Teri N; Mezic, Katherine G; Herce, Henry D; Duffy, Ellen B; Bourges, Anais; Pryshchep, Sergey; Juarez, Oscar; Barquera, Blanca

    2015-04-21

    RNF is a redox-driven ion (Na(+) and in one case possibly H(+)) transporter present in many prokaryotes. It has been proposed that RNF performs a variety of reactions in different organisms, delivering low-potential reducing equivalents for specific cellular processes. RNF shares strong homology with the Na(+)-pumping respiratory enzyme Na(+)-NQR, although there are significant differences in subunit and redox cofactor composition. Here we report a topological analysis of the six subunits of RNF from Vibrio cholerae. Although individual subunits from other organisms have previously been studied, this is the first complete, experimentally derived, analysis of RNF from any one source. This has allowed us to identify and confirm key properties of RNF. The putative NADH binding site in RnfC is located on the cytoplasmic side of the membrane. FeS centers in RnfB and RnfC are also located on the cytoplasmic side. However, covalently attached FMNs in RnfD and RnfG are both located in the periplasm. RNF also contains a number of acidic residues that correspond to functionally important groups in Na(+)-NQR. The acidic residues involved in Na(+) uptake and many of those implicated in Na(+) translocation are topologically conserved. The topology of RNF closely matches the topology represented in the newly published structure of Na(+)-NQR, consistent with the close relation between the two enzymes. The topology of RNF is discussed in the context of the current structural model of Na(+)-NQR, and the proposed functionality of the RNF complex itself. PMID:25831459

  2. O-antigen and Core Carbohydrate of Vibrio fischeri Lipopolysaccharide

    PubMed Central

    Post, Deborah M. B.; Yu, Liping; Krasity, Benjamin C.; Choudhury, Biswa; Mandel, Mark J.; Brennan, Caitlin A.; Ruby, Edward G.; McFall-Ngai, Margaret J.; Gibson, Bradford W.; Apicella, Michael A.

    2012-01-01

    Vibrio fischeri exists in a symbiotic relationship with the Hawaiian bobtail squid, Euprymna scolopes, where the squid provides a home for the bacteria, and the bacteria in turn provide camouflage that helps protect the squid from night-time predators. Like other Gram-negative organisms, V. fischeri expresses lipopolysaccharide (LPS) on its cell surface. The structure of the O-antigen and the core components of the LPS and their possible role in colonization of the squid have not previously been determined. In these studies, an O-antigen ligase mutant, waaL, was utilized to determine the structures of these LPS components and their roles in colonization of the squid. WaaL ligates the O-antigen to the core of the LPS; thus, LPS from waaL mutants lacks O-antigen. Our results show that the V. fischeri waaL mutant has a motility defect, is significantly delayed in colonization, and is unable to compete with the wild-type strain in co-colonization assays. Comparative analyses of the LPS from the wild-type and waaL strains showed that the V. fischeri LPS has a single O-antigen repeat composed of yersiniose, 8-epi-legionaminic acid, and N-acetylfucosamine. In addition, the LPS from the waaL strain showed that the core structure consists of l-glycero-d-manno-heptose, d-glycero-d-manno-heptose, glucose, 3-deoxy-d-manno-octulosonic acid, N-acetylgalactosamine, 8-epi-legionaminic acid, phosphate, and phosphoethanolamine. These studies indicate that the unusual V. fischeri O-antigen sugars play a role in the early phases of bacterial colonization of the squid. PMID:22247546

  3. Features governing symbiont persistence in the squid-vibrio association.

    PubMed

    Koch, Eric J; Miyashiro, Tim; McFall-Ngai, Margaret J; Ruby, Edward G

    2014-03-01

    Experimental studies of the interaction between host and symbiont in a maturing symbiotic organ have presented a challenge for most animal-bacterial associations. Advances in the rearing of the host squid Euprymna scolopes have enabled us to explore the relationship between a defect in symbiont light production and late-stage development (e.g. symbiont persistence and tissue morphogenesis) by experimental colonization with specific strains of the symbiont Vibrio fischeri. During the first 4 weeks postinoculation of juvenile squid, the population of wild-type V. fischeri increased 100-fold; in contrast, a strain defective in light production (?lux) colonized normally the first day, but exhibited an exponential decline to undetectable levels over subsequent weeks. Co-colonization of organs by both strains affected neither the trajectory of colonization by wild type nor the decline of ?lux levels. Uninfected animals retained the ability to be colonized for at least 2 weeks posthatch. However, once colonized by the wild-type strain for 5 days, a subsequent experimentally induced loss of the symbionts could not be followed by a successful recolonization, indicating the host's entry into a refractory state. However, animals colonized by the ?lux before the loss of their symbionts were receptive to recolonization. Analyses of animals colonized with either a wild-type or a ?lux strain revealed slight, if any, differences in the developmental regression of the ciliated light-organ tissues that facilitate the colonization process. Thus, some other feature(s) of the ?lux strain's defect also may be responsible for its inability to persist, and its failure to induce a refractory state in the host. PMID:24118200

  4. Updating the Vibrio clades defined by multilocus sequence phylogeny: proposal of eight new clades, and the description of Vibrio tritonius sp. nov.

    PubMed Central

    Sawabe, Tomoo; Ogura, Yoshitoshi; Matsumura, Yuta; Feng, Gao; Amin, AKM Rohul; Mino, Sayaka; Nakagawa, Satoshi; Sawabe, Toko; Kumar, Ramesh; Fukui, Yohei; Satomi, Masataka; Matsushima, Ryoji; Thompson, Fabiano L.; Gomez-Gil, Bruno; Christen, Richard; Maruyama, Fumito; Kurokawa, Ken; Hayashi, Tetsuya

    2013-01-01

    To date 142 species have been described in the Vibrionaceae family of bacteria, classified into seven genera; Aliivibrio, Echinimonas, Enterovibrio, Grimontia, Photobacterium, Salinivibrio and Vibrio. As vibrios are widespread in marine environments and show versatile metabolisms and ecologies, these bacteria are recognized as one of the most diverse and important marine heterotrophic bacterial groups for elucidating the correlation between genome evolution and ecological adaptation. However, on the basis of 16S rRNA gene phylogeny, we could not find any robust monophyletic lineages in any of the known genera. We needed further attempts to reconstruct their evolutionary history based on multilocus sequence analysis (MLSA) and/or genome wide taxonomy of all the recognized species groups. In our previous report in 2007, we conducted the first broad multilocus sequence analysis (MLSA) to infer the evolutionary history of vibrios using nine housekeeping genes (the 16S rRNA gene, gapA, gyrB, ftsZ, mreB, pyrH, recA, rpoA, and topA), and we proposed 14 distinct clades in 58 species of Vibrionaceae. Due to the difficulty of designing universal primers that can amplify the genes for MLSA in every Vibrionaceae species, some clades had yet to be defined. In this study, we present a better picture of an updated molecular phylogeny for 86 described vibrio species and 10 genome sequenced Vibrionaceae strains, using 8 housekeeping gene sequences. This new study places special emphasis on (1) eight newly identified clades (Damselae, Mediterranei, Pectenicida, Phosphoreum, Profundum, Porteresiae, Rosenbergii, and Rumoiensis); (2) clades amended since the 2007 proposal with recently described new species; (3) orphan clades of genomospecies F6 and F10; (4) phylogenetic positions defined in 3 genome-sequenced strains (N418, EX25, and EJY3); and (5) description of V. tritonius sp. nov., which is a member of the “Porteresiae” clade. PMID:24409173

  5. Clostridium ultunense sp. nov., a Mesophilic Bacterium Oxidizing Acetate in Syntrophic Association with a Hydrogenotrophic Met hanogenic Bacterium

    Microsoft Academic Search

    ANNA SCHNURER; BERNHARD SCHINK; BO H. SVENSSON

    A syntrophic acetate-oxidizing bacterium, strain BST (T = type strain), was isolated from a previously described mesophilic triculture that was able to syntrophically oxidize acetate and form methane in stoichi- ometric amounts. Strain BST was isolated with substrates typically utilized by homoacetogenic bacteria. Strain BST was a spore-forming, gram-positive, rod-shaped organism which utilized formate, glucose, ethylene glycol, cysteine, betaine, and

  6. Identification and characteristic analysis of the ampC gene encoding beta-lactamase from Vibrio fischeri.

    PubMed

    Weng, Shu-Fen; Chao, Yuh-Fen; Lin, Juey-Wen

    2004-02-13

    Vibrio fischeri ATCC 7744 is an ampicillin resistant (Amp(r)) marine luminous bacterium. The MIC test indicates that V. fischeri is highly resistant to penicillins, and susceptible to cephalosporins. V. fischeri ampC gene was cloned and identified. Nucleotide sequence of an unidentified ufo gene and the ampC, ppiB genes (GenBank Accession No. AY438037) has been determined; whereas the ampC gene encodes the beta-lactamase (AmpC) and the ppiB gene encodes the peptidyl-prolyl cis-trans isomerase B. Alignment and comparison show that V. fischeri beta-lactamase is homologous to the related species'. The specific amino acid residues STFK (62nd to 65th), SDN (122nd to 124th), and D (155th) located 34 residues downstream from the SDN loop of the class A beta-lactamases are highly conserved, but the KTG is not found. V. fischeri ampC gene encoding beta-lactamase has a calculated M(r) 31,181 and comprises 283 amino acid residues (pI 5.35). There is a signal peptide of 18 amino acid residues MKIKPFLFGLIVLANNAI in the pro-beta-lactamase, which functioned for secretion; thus, the matured protein only has M(r) 29,197 and comprises 265 amino acid residues (pI 4.95). SDS-PAGE and the beta-lactamase functional assays elicit that the M(r) of the beta-lactamases are close to 29kDa. IEF and the beta-lactamase functional assays show that the beta-lactamases' pI are close to 4.8 as predicted. The results elucidate that V. fischeri ampC gene and the cloned ampC gene in Escherichia coli are the same one. The gene order of the ampC and the related genes is -ufo-(P*-intern)-ampC-ppiB--> (P*-intern: intern promoter for sub-regulation), whereas the P*-intern promoter displays the function to lead the ampC gene's expression for stress response. PMID:14741712

  7. RESPONSES OF OYSTERS AND THEIR HEMOCYTES TO CLINICAL AND ENVIRONMENTAL ISOLATES OF VIBRIO PARAHAEMOLYTICUS

    EPA Science Inventory

    Interactions of Vibrio parahaemolyticus with oysters and oyster hemocytes were studied using three environmental isolates (1094, 1163 and ATCC 17802) and three clinical isolates (2030, 2062, 2107). Clinical isolates were from patients who became ill during the June 1998 food pois...

  8. Draft Genome Sequences of Four Closely Linked Vibrio vulnificus Isolates from the Biotype 1 Environmental Genotype

    PubMed Central

    Phillips, Kelsey E.; Schipma, Matthew J.

    2015-01-01

    Biotype 1 of Vibrio vulnificus, which causes severe invasive intestinal and wound infections, is split into two genotypes with all previously sequenced clinical isolates from the C genotypes. We report here the whole-genome sequencing of two clinical isolates and two closely linked oyster isolates from the E genotype for comparative studies. PMID:25593245

  9. Integrative genome-scale metabolic analysis of Vibrio vulnificus for drug targeting and discovery

    Microsoft Academic Search

    Hyun Uk Kim; Soo Young Kim; Haeyoung Jeong; Tae Yong Kim; Jae Jong Kim; Hyon E Choy; Kyu Yang Yi; Joon Haeng Rhee; Sang Yup Lee

    2011-01-01

    Although the genomes of many microbial pathogens have been studied to help identify effective drug targets and novel drugs, such efforts have not yet reached full fruition. In this study, we report a systems biological approach that efficiently utilizes genomic information for drug targeting and discovery, and apply this approach to the opportunistic pathogen Vibrio vulnificus CMCP6. First, we partially

  10. BIOLOGICAL PROPERTIES (IN VITRO) EXHIBITED BY FREE-LIVING AND SYMBIOTIC VIBRIO ISOLATES

    E-print Network

    McFall-Ngai, Margaret

    BIOLOGICAL PROPERTIES (IN VITRO) EXHIBITED BY FREE- LIVING AND SYMBIOTIC VIBRIO ISOLATES V. NAIR, NM 88003-8001, USA Abstract Adhesion and biofilm forming ability of symbiotic bacteria play a crucial strains (free-living and symbiotic). Since these symbiotic factors contribute in some fashion

  11. Recognition between symbiotic Vibrio fischeri and the haemocytes of Euprymna scolopes

    E-print Network

    McFall-Ngai, Margaret

    Recognition between symbiotic Vibrio fischeri and the haemocytes of Euprymna scolopes Spencer V, but also continue to exclude other bacteria. Investigation of the role of the innate immune system. Thus, discrimination by this component of the squid immune system occurs at the level of haemocyte

  12. Distribution of Virulence Genes in Clinical and Environmental Vibrio cholerae Strains in Bangladesh

    PubMed Central

    Hasan, Nur A.; Ceccarelli, Daniela; Grim, Christopher J.; Taviani, Elisa; Choi, Jinna; Sadique, Abdus; Alam, Munirul; Siddique, Abul K.; Sack, R. Bradley; Huq, Anwar

    2013-01-01

    Vibrio cholerae, an environmental organism, is a facultative human pathogen. Here, we report the virulence profiles, comprising 18 genetic markers, of 102 clinical and 692 environmental V. cholerae strains isolated in Bangladesh between March 2004 and January 2006, showing the variability of virulence determinants within the context of public health. PMID:23872570

  13. Distribution of virulence genes in clinical and environmental Vibrio cholerae strains in Bangladesh.

    PubMed

    Hasan, Nur A; Ceccarelli, Daniela; Grim, Christopher J; Taviani, Elisa; Choi, Jinna; Sadique, Abdus; Alam, Munirul; Siddique, Abul K; Sack, R Bradley; Huq, Anwar; Colwell, Rita R

    2013-09-01

    Vibrio cholerae, an environmental organism, is a facultative human pathogen. Here, we report the virulence profiles, comprising 18 genetic markers, of 102 clinical and 692 environmental V. cholerae strains isolated in Bangladesh between March 2004 and January 2006, showing the variability of virulence determinants within the context of public health. PMID:23872570

  14. Diversity and Seasonality of Bioluminescent Vibrio cholerae Populations in Chesapeake Bay

    Microsoft Academic Search

    Young-Gun Zo; Nipa Chokesajjawatee; Christopher Grim; Eiji Arakawa; Haruo Watanabe; Rita R. Colwell

    2009-01-01

    Association of luminescence with phenotypic and genotypic traits and with environmental parameters was determined for 278 strains of Vibrio cholerae isolated from the Chesapeake Bay during 1998 to 2000. Three clusters of luminescent strains (A, B, and C) and two nonluminescent clusters (X and Y) were identified among 180 clonal types. V. cholerae O1 strains isolated during pandemics and endemic

  15. Vaccination against Vibrio (Campylobacter) fetus infection in sheep in late pregnancy

    Microsoft Academic Search

    NJ Gilmour; DA Thompson; J Fraser

    1975-01-01

    A single injection of vaccine containing disrupted formol-killed Vibrio (campylobacter) fetus var intestinalis serotype V was shown to give good protection against abortion from an oral challenge of the same serotype administered simultaneously. Protection was also afforded by vaccination at the time of the first abortion in sheep infected orally one month previously. These results suggest that vaccination subsequent to

  16. Incidence of highly genetically diversified Vibrio parahaemolyticus in seafood imported from Asian countries

    Microsoft Academic Search

    H.-C Wong; M.-C Chen; S.-H Liu; D.-P Liu

    1999-01-01

    Vibrio parahaemolyticus is an important pathogen of humans and aquacultured animals, especially in Asian countries. In this study, we examined 686 samples of seafood imported from Hong Kong, Indonesia, Thailand and Vietnam for V. parahaemolyticus. V. parahaemolyticus was recovered from 315 (45.9%) samples. The incidence of V. parahaemolyticus in products from Hong Kong and Thailand was markedly higher than the

  17. Murine macrophage inflammatory cytokine production and immune activation in response to Vibrio parahaemolyticus infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vibrio parahaemolyticus is the most common cause of bacterial seafood-related illness in the United States. Currently, there is a dearth of literature regarding immunity to infection with this pathogen. Here we studied V. parahaemolyticus-infected RAW 264.7 murine macrophage detecting both pro- and...

  18. Complete Genome Sequences of a Clinical Isolate and an Environmental Isolate of Vibrio parahaemolyticus.

    PubMed

    Lüdeke, Catharina H M; Kong, Nguyet; Weimer, Bart C; Fischer, Markus; Jones, Jessica L

    2015-01-01

    Vibrio parahaemolyticus is the leading cause of seafood-borne infections in the United States. We report complete genome sequences for two V. parahaemolyticus strains isolated in 2007, CDC_K4557 and FDA_R31 of clinical and oyster origin, respectively. These two sequences might assist in the investigation of differential virulence of this organism. PMID:25814612

  19. Rapid polymerase chain reaction method for detection of Kanagawa positive Vibrio parahaemolyticus in seafoods

    Microsoft Academic Search

    I. Karunasagar; G. Sugumar; P. J. A. Reilly

    1996-01-01

    Detection of Kanagawa positive strains of Vibrio parahaemolyticus by polymerase chain reaction (PCR) was tested. Primer pairs for specific amplification of tdh gene fragment is described. The assay could detect contamination of seafood homogenate when PCR was performed using lysate prepared directly from fish homogenates. The sensitivity of the assay could be improved to detect less than 10 cells of

  20. Complete Genome Sequences of a Clinical Isolate and an Environmental Isolate of Vibrio parahaemolyticus

    PubMed Central

    Lüdeke, Catharina H. M.; Kong, Nguyet; Weimer, Bart C.; Fischer, Markus

    2015-01-01

    Vibrio parahaemolyticus is the leading cause of seafood-borne infections in the United States. We report complete genome sequences for two V. parahaemolyticus strains isolated in 2007, CDC_K4557 and FDA_R31 of clinical and oyster origin, respectively. These two sequences might assist in the investigation of differential virulence of this organism. PMID:25814612