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Sample records for bacterium vibrio harveyi

  1. Chitin Degradation Proteins Produced by the Marine Bacterium Vibrio harveyi Growing on Different Forms of Chitin.

    PubMed

    Svitil, A L; Chadhain, S; Moore, J A; Kirchman, D L

    1997-02-01

    Relatively little is known about the number, diversity, and function of chitinases produced by bacteria, even though chitin is one of the most abundant polymers in nature. Because of the importance of chitin, especially in marine environments, we examined chitin-degrading proteins in the marine bacterium Vibrio harveyi. This bacterium had a higher growth rate and more chitinase activity when grown on (beta)-chitin (isolated from squid pen) than on (alpha)-chitin (isolated from snow crab), probably because of the more open structure of (beta)-chitin. When exposed to different types of chitin, V. harveyi excreted several chitin-degrading proteins into the culture media. Some chitinases were present with all of the tested chitins, while others were unique to a particular chitin. We cloned and identified six separate chitinase genes from V. harveyi. These chitinases appear to be unique based on DNA restriction patterns, immunological data, and enzyme activity. This marine bacterium and probably others appear to synthesize separate chitinases for efficient utilization of different forms of chitin and chitin by-products. PMID:16535505

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

    PubMed

    Wang, Zheng; Hervey, W Judson; Kim, Seongwon; Lin, Baochuan; Vora, Gary J

    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

  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. Elongation of exogenous fatty acids by the bioluminescent bacterium Vibrio harveyi

    SciTech Connect

    Byers, D.M.

    1989-01-01

    Bioluminescent bacteria require myristic acid (C14:0) to produce the myristaldehyde substrate of the light-emitting luciferase reaction. Since both endogenous and exogenous C14:0 can be used for this purpose, the metabolism of exogenous fatty acids by luminescent bacteria has been investigated. Both Vibrio harveyi and Vibrio fischeri incorporated label from (1-14C)myristic acid (C14:0) into phospholipid acyl chains as well as into CO2. In contrast, Photobacterium phosphoreum did not exhibit phospholipid acylation or beta-oxidation using exogenous fatty acids. Unlike Escherichia coli, the two Vibrio species can directly elongate fatty acids such as octanoic (C8:0), lauric (C12:0), and myristic acid, as demonstrated by radio-gas liquid chromatography. The induction of bioluminescence in late exponential growth had little effect on the ability of V. harveyi to elongate fatty acids, but it did increase the amount of C14:0 relative to C16:0 labeled from (14C)C8:0. This was not observed in a dark mutant of V. harveyi that is incapable of supplying endogenous C14:0 for luminescence. Cerulenin preferentially decreased the labeling of C16:0 and of unsaturated fatty acids from all 14C-labeled fatty acid precursors as well as from (14C)acetate, suggesting that common mechanisms may be involved in elongation of fatty acids from endogenous and exogenous sources. Fatty acylation of the luminescence-related synthetase and reductase enzymes responsible for aldehyde synthesis exhibited a chain-length preference for C14:0, which also was indicated by reverse-phase thin-layer chromatography of the acyl groups attached to these enzymes. The ability of V. harveyi to activate and elongate exogenous fatty acids may be related to an adaptive requirement to metabolize intracellular C14:0 generated by the luciferase reaction during luminescence development.

  5. Azide anions inhibit GH-18 endochitinase and GH-20 Exo ?-N-acetylglucosaminidase from the marine bacterium Vibrio harveyi.

    PubMed

    Sirimontree, Paknisa; Fukamizo, Tamo; Suginta, Wipa

    2016-02-01

    Vibrio harveyi is a bioluminescent marine bacterium that utilizes chitin as its sole source of energy. In the course of chitin degradation, the bacterium primarily secretes an endochitinase A (VhChiA) to hydrolyze chitin, generating chitooligosaccharide fragments that are readily transported into the cell and broken down to GlcNAc monomers by an exo ?-N-acetylglucosaminidase (VhGlcNAcase). Here we report that sodium salts, especially sodium azide, inhibit two classes of these chitin-degrading enzymes (VhChiA and VhGlcNAcase) with distinct modes of action. Kinetic analysis of the enzymatic hydrolysis of pNP-glycoside substrates reveals that sodium azide inhibition of VhChiA has a mixed-type mode, but that it inhibits VhGlcNAcase competitively. We propose that azide anions inhibit chitinase activity by acting as strong nucleophiles that attack C? of the catalytic Glu or C? of the neighbouring Asp residues. Azide anions may bind not only to the catalytic centre, but also to the other subsites in the substrate-binding cleft of VhChiA. In contrast, azide anions may merely occupy the small-binding pocket of VhGlcNAcase, thereby blocking the accessibility of its active site by short-chain substrates. PMID:26330565

  6. Expression, purification, crystallization and preliminary crystallographic analysis of a GH20 ?-N-acetylglucosaminidase from the marine bacterium Vibrio harveyi.

    PubMed

    Meekrathok, Piyanat; Brger, Marco; Porfetye, Arthur T; Vetter, Ingrid R; Suginta, Wipa

    2015-04-01

    Vibrio harveyi ?-N-acetylglucosaminidase (VhGlcNAcase) is a new member of the GH20 glycoside hydrolase family responsible for the complete degradation of chitin fragments, with N-acetylglucosamine (GlcNAc) monomers as the final products. In this study, the crystallization and preliminary crystallographic data of wild-type VhGlcNAcase and its catalytically inactive mutant D437A in the absence and the presence of substrate are reported. Crystals of wild-type VhGlcNAcase were grown in 0.1?M sodium acetate pH 4.6, 1.4?M sodium malonate, while crystals of the D437A mutant were obtained in 0.1?M bis-tris pH 7.5, 0.1?M sodium acetate, 20% PEG 3350. X-ray data from the wild-type and the mutant crystals were collected at a synchrotron-radiation light source and were complete to a resolution of 2.5?. All crystals were composed of the same type of dimer, with the substrate N,N'-diacetylglucosamine (GlcNAc? or diNAG) used for soaking was cleaved by the active enzyme, leaving only a single GlcNAc molecule bound to the protein. PMID:25849504

  7. Chitoporin from the Marine Bacterium Vibrio harveyi: PROBING THE ESSENTIAL ROLES OF TRP136 AT THE SURFACE OF THE CONSTRICTION ZONE.

    PubMed

    Chumjan, Watcharin; Winterhalter, Mathias; Schulte, Albert; Benz, Roland; Suginta, Wipa

    2015-07-31

    VhChiP is a sugar-specific porin present in the outer membrane of the marine bacterium Vibrio harveyi. VhChiP is responsible for the uptake of chitin oligosaccharides, with particular selectivity for chitohexaose. In this study, we employed electrophysiological and biochemical approaches to demonstrate that Trp(136), located at the mouth of the VhChiP pore, plays an essential role in controlling the channel's ion conductivity, chitin affinity, and permeability. Kinetic analysis of sugar translocation obtained from single channel recordings indicated that the Trp(136) mutations W136A, W136D, W136R, and W136F considerably reduce the binding affinity of the protein channel for its best substrate, chitohexaose. Liposome swelling assays confirmed that the Trp(136) mutations decreased the rate of bulk chitohexaose permeation through the VhChiP channel. Notably, all of the mutants show increases in the off-rate for chitohexaose of up to 20-fold compared with that of the native channel. Furthermore, the cation/anion permeability ratio Pc/Pa is decreased in the W136R mutant and increased in the W136D mutant. This demonstrates that the negatively charged surface at the interior of the protein lumen preferentially attracts cationic species, leading to the cation selectivity of this trimeric channel. PMID:26082491

  8. 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 (δ15NAAs) 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 δ15NAAs patterns and how this variability influences marine bacteria, an important mediator of trophic transfer and organic matter transformation. We explored whether marine bacterial δ15NAAs profiles change depending on the type and C:N ratio of the substrate. The δ15NAAs 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 δ15N offset values normalized to glutamate + glutamine δ15N revealed that δ15NAAs profiles differed depending on the N source and C:N ratio of the substrate. High variability in the δ15N offset of alanine and valine largely explained this bacterial δ15NAAs profile variability. PCA was also conducted using bacterial and phytoplankton (cyanobacteria and eukaryotic algae) δ15NAAs profile data reported previously. The results revealed that bacterial δ15NAAs patterns were distinct from those of phytoplankton. Therefore, the δ15NAAs 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.

  9. 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.

  10. Reprogramming of Vibrio harveyi gene expression during adaptation in cold seawater.

    PubMed

    Montnchez, Itxaso; Arana, Ins; Parada, Claudia; Garaizabal, Idoia; Orruo, Maite; Barcina, Isabel; Kaberdin, Vladimir R

    2014-01-01

    The life and survival of the marine bacterium Vibrio harveyi during its adaptation in natural aquatic systems is highly influenced by the availability of nutrients and temperature. To learn about adaptation strategies evolved by this bacterium to cope with drastic temperature downshifts and nutrients depletion, we have studied the phenotypical and gene expression changes occurring in V. harveyi during its adaptation to cold seawater. We found that incubation in cold seawater up to 12 h did not cause any significant morphological changes in V. harveyi and had no effect on the number of viable and culturable cells. Microarray analysis revealed that the V. harveyi response to cold seawater leads to up- and downregulation of numerous genes controlling the central carbon metabolism, nucleotide and amino acid biosynthesis as well as DNA repair. In addition, expression of some genes controlling biosynthesis of lipids, molecular transport, and energy production was altered to likely affect the composition and properties of the V. harveyi cell envelope, thus implying the putative role of this compartment in adaptation to stress. Here, we discuss these results with regard to the putative adaptive responses likely triggered by V. harveyi to cope with environmental challenges in natural aquatic systems. PMID:24102529

  11. Small RNA Control of Cell-to-Cell Communication in Vibrio Harveyi and Vibrio Cholerae

    NASA Astrophysics Data System (ADS)

    Svenningsen, Sine Lo

    Quorum sensing is a process of cell-to-cell communication, by which bacteria coordinate gene expression and behavior on a population-wide scale. Quorum sensing is accomplished through production, secretion, and subsequent detection of chemical signaling molecules termed autoinducers. The human pathogen Vibrio cholerae and the marine bioluminescent bacterium Vibrio harveyi incorporate information from multiple autoinducers, and also environmental signals and metabolic cues into their quorum-sensing pathways. At the core of these pathways lie several homologous small regulatory RNA molecules, the Quorum Regulatory RNAs. Small noncoding RNAs have emerged throughout the bacterial and eukaryotic kingdoms as key regulators of behavioral and developmental processes. Here, I review our present understanding of the role of the Qrr small RNAs in integrating quorum-sensing signals and in regulating the individual cells response to this information.

  12. Production of monoclonal antibodies for detection of Vibrio harveyi.

    PubMed

    Phianphak, Wannipa; Rengpipat, Sirirat; Rukpratanporn, Sombat; Longyant, Siwaporn; Chaivisuthangkura, Parin; Sithigorngul, Weerawan; Sithigorngul, Paisarn

    2005-02-28

    Monoclonal antibodies (MAbs) against Vibrio harveyi were produced from mice immunized with heat-killed and SDS-mercaptoethanol-treated highly virulent V. harveyi 639. Fifteen MAbs were selected and sorted into 6 groups according to their specificity to various proteins of apparent molecular weight ranging from 8 to 49 kDa. Some antibodies were used for detection of V. harveyi at concentrations as low as 10(4) CFU ml(-1) using immunodot blots. Most of the selected MAbs did not show cross-reactivity to other Vibrio species and other gram-negative bacteria tested. Only 1 MAb (VH39-4E) showed slight cross-reactivity to Aeromonas hydrophila. Another MAb (VH24-8H) bound lightly to V. harveyi 1526 but strongly to V. harveyi 639, allowing rapid differentiation. Two of the MAb groups were used to localize V. harveyi in tissues of infected black tiger shrimp Penaeus monodon by immunohistochemistry. This study demonstrates the versatility of a highly specific immunological tool for the detection of V. harveyi in aquaculture and opens the way for further development of convenient test kits. PMID:15819431

  13. Chitoporin from Vibrio harveyi, a channel with exceptional sugar specificity.

    PubMed

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

    2013-04-19

    Chitoporin (VhChiP) is a sugar-specific channel responsible for the transport of chitooligosaccharides through the outer membrane of the marine bacterium Vibrio harveyi. Single channel reconstitution into black lipid membrane allowed single chitosugar binding events in the channel to be resolved. VhChiP has an exceptionally high substrate affinity, with a binding constant of K = 5.0 10(6) M(-1) for its best substrate (chitohexaose). The on-rates of chitosugars depend on applied voltages, as well as the side of the sugar addition, clearly indicating the inherent asymmetry of the VhChiP lumen. The binding affinity of VhChiP for chitohexaose is 1-5 orders of magnitude larger than that of other known sugar-specific porins for their preferred substrates. Thus, VhChiP is the most potent sugar-specific channel reported to date, with its high efficiency presumably reflecting the need for the bacterium to take up chitin-containing nutrients promptly under turbulent aquatic conditions to exploit them efficiently as its sole source of energy. PMID:23447539

  14. Draft Genome Sequence of the Opportunistic Marine Pathogen Vibrio harveyi Strain E385.

    PubMed

    Yu, Mingjia; Ren, Chunhua; Qiu, Jinrong; Luo, Peng; Zhu, Ruyi; Zhao, Zhe; Hu, Chaoqun

    2013-01-01

    Vibrio harveyi strain E385 was isolated from a diseased cage-cultured grouper in Daya Bay, China. Phylogenetic analysis based on the 16S rRNA gene sequence showed similarity with V. harveyi strain BAA-1116. We sequenced the pathogenic strain V. harveyi E385 and compared the genome with that of the nonpathogenic strain V. harveyi BAA-1116. PMID:24336361

  15. 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

  16. Negative Feedback in the Vibrio harveyi Quorum-Sensing Circuit

    NASA Astrophysics Data System (ADS)

    Teng, Shu-Wen; Schaffer, Jessie; Wingreen, Ned; Bassler, Bonnie; Phuan Ong, Nai

    2010-03-01

    Quorum sensing is the mechanism by which bacteria communicate and synchronize group behaviors. Multiple feedbacks have been identified in the model quorum-sensing bacterium Vibrio harveyi, but it has been unclear how these feedbacks interact in individual cells to control the fidelity of signal transduction. We measured the copy number distribution of the master regulators to quantify the activity of the signaling network. We find that the feedbacks affect the production rate, level, and noise of the core quorum-sensing components. Using fluorescence time-lapse microscopy, we directly observed the master regulator in individual cells, and analyzed the persistence of heterogeneity in terms of the normalized time-delayed direct correlation. Our findings suggest that feedback from small regulatory RNAs regulates a receptor to control the noise level in signal transduction. We further tested this model by re-engineering the gene circuit to specifically diminish this feedback. We conclude that negative feedbacks mediated by sRNAs permit fine-tuning of gene regulation, thereby increasing the fidelity of signal transduction.

  17. Multiple small RNAs act additively to integrate sensory information and control quorum sensing in Vibrio harveyi

    PubMed Central

    Tu, Kimberly C.; Bassler, Bonnie L.

    2007-01-01

    Quorum sensing is a cell–cell communication mechanism that bacteria use to collectively regulate gene expression and, at a higher level, to coordinate group behavior. In the bioluminescent marine bacterium Vibrio harveyi, sensory information from three independent quorum-sensing systems converges on the shared response regulator LuxO. When LuxO is phosphorylated, it activates the expression of a putative repressor that destabilizes the mRNA encoding the master quorum-sensing transcriptional regulator LuxR. In the closely related species Vibrio cholerae, this repressor was revealed to be the RNA chaperone Hfq together with four small regulatory RNAs (sRNAs) called Qrr1–4 (quorum regulatory RNA). Here, we identify five Qrr sRNAs that control quorum sensing in V. harveyi. Mutational analysis reveals that only four of the five Qrrs are required for destabilization of the luxR mRNA. Surprisingly, unlike in V. cholerae where the sRNAs act redundantly, in V. harveyi, the Qrr sRNAs function additively to control quorum sensing. This latter mechanism produces a gradient of LuxR that, in turn, enables differential regulation of quorum-sensing target genes. Other regulators appear to be involved in control of V. harveyi qrr expression, allowing the integration of additional sensory information into the regulation of quorum-sensing gene expression. PMID:17234887

  18. Synergistic activation of quorum sensing in Vibrio harveyi.

    PubMed

    Mandabi, Aviad; Ganin, Hadas; Meijler, Michael M

    2015-09-15

    Autoinducer-2 (AI-2) has been suggested to serve as a ubiquitous quorum sensing (QS) signal that mediates intra- and interspecies cross-talk between bacteria. To add tools for the study of its function in bacterial communication, we present a new and an improved synthetic route to AI-2 and aromatic analogues. We used this strategy to prepare naphthyl-DPD, and observed remarkably high synergistic activity at low nanomolar concentrations for this analogue in Vibrio harveyi. PMID:26248803

  19. A model for signal transduction during quorum sensing in Vibrio harveyi

    NASA Astrophysics Data System (ADS)

    Banik, Suman K.; Fenley, Andrew T.; Kulkarni, Rahul V.

    2009-12-01

    We present a framework for analyzing luminescence regulation during quorum sensing in the bioluminescent bacterium Vibrio harveyi. Using a simplified model for signal transduction in the quorum sensing pathway, we identify key dimensionless parameters that control the system's response. These parameters are estimated using experimental data on luminescence phenotypes for different mutant strains. The corresponding model predictions are consistent with results from other experiments which did not serve as input for determining model parameters. Furthermore, the proposed framework leads to novel testable predictions for luminescence phenotypes and for responses of the network to different perturbations.

  20. Effect of organic acids on shrimp pathogen, Vibrio harveyi.

    PubMed

    Mine, Saori; Boopathy, Raj

    2011-07-01

    Shrimp farming accounts for more than 40% of the world shrimp production. Luminous vibriosis is a shrimp disease that causes major economic losses in the shrimp industry as a result of massive shrimp kills due to infection. Some farms in the South Asia use antibiotics to control Vibrio harveyi, a responsible pathogen for luminous vibriosis. However, the antibiotic-resistant strain was found recently in many shrimp farms, which makes it necessary to develop alternative pathogen control methods. Short-chain fatty acids are metabolic products of organisms, and they have been used as food preservatives for a long time. Organic acids are also commonly added in feeds in animal husbandry, but not in aquaculture. In this study, growth inhibitory effects of short-chain fatty acids, namely formic acid, acetic acid, propionic acid, and butyric acid, on V. harveyi were investigated. Among four acids, formic acid showed the strongest inhibitory effect followed by acetic acid, propionic acid, and butyric acid. The minimum inhibitory concentration (MIC) of 0.035% formic acid suppressed growth of V. harveyi. The major inhibitory mechanism seems to be the pH effect of organic acids. The effective concentration 50 (EC50) values at 96 h inoculation for all organic acids were determined to be 0.023, 0.041, 0.03, and 0.066% for formic, acetic, propionic, and butyric acid, respectively. The laboratory study results are encouraging to formulate shrimp feeds with organic acids to control vibrio infection in shrimp aquaculture farms. PMID:21479932

  1. Improved quorum sensing capacity by culturing Vibrio harveyi in microcapsules.

    PubMed

    Gao, Meng; Song, Huiyi; Liu, Xiudong; Yu, Weiting; Ma, Xiaojun

    2016-04-01

    Microcapsule entrapped low density cells with culture (ELDCwc), different from free cell culture, conferred stronger stress resistance and improved cell viability of microorganisms. In this paper, the quorum sensing (QS) system of Vibrio harveyi was used to investigate changes when cells were cultured in microcapsules. Cells in ELDCwc group grew into cell aggregates, which facilitated cell-cell communication and led to increased bioluminescence intensity. Moreover, the luxS-AI-2 system, a well-studied QS signal pathway, was detected as both luxS gene and the AI-2 signaling molecule, and the results were analyzed with respect to QS capacity of unit cell. The V. harveyi of ELDCwc also showed higher relative gene expression and stronger quorum sensing capacity when compared with free cells. In conclusion, the confined microcapsule space can promote the cell aggregates formation, reduce cell-cell communication distance and increase local concentration of signal molecule, which are beneficial to bacterial QS. PMID:26364746

  2. A nitric oxide-responsive quorum sensing circuit in Vibrio harveyi regulates flagella production and biofilm formation.

    PubMed

    Henares, Bernadette M; Xu, Yueming; Boon, Elizabeth M

    2013-01-01

    Cell signaling plays an important role in the survival of bacterial colonies. They use small molecules to coordinate gene expression in a cell density dependent manner. This process, known as quorum sensing, helps bacteria regulate diverse functions such as bioluminescence, biofilm formation and virulence. In Vibrio harveyi, a bioluminescent marine bacterium, four parallel quorum-sensing systems have been identified to regulate light production. We have previously reported that nitric oxide (NO), through the H-NOX/HqsK quorum sensing pathway contributes to light production in V. harveyi through the LuxU/LuxO/LuxR quorum sensing pathway. In this study, we show that nitric oxide (NO) also regulates flagellar production and enhances biofilm formation. Our data suggest that V. harveyi is capable of switching between lifestyles to be able to adapt to changes in the environment. PMID:23965964

  3. A Nitric Oxide-Responsive Quorum Sensing Circuit in Vibrio harveyi Regulates Flagella Production and Biofilm Formation

    PubMed Central

    Henares, Bernadette M.; Xu, Yueming; Boon, Elizabeth M.

    2013-01-01

    Cell signaling plays an important role in the survival of bacterial colonies. They use small molecules to coordinate gene expression in a cell density dependent manner. This process, known as quorum sensing, helps bacteria regulate diverse functions such as bioluminescence, biofilm formation and virulence. In Vibrio harveyi, a bioluminescent marine bacterium, four parallel quorum-sensing systems have been identified to regulate light production. We have previously reported that nitric oxide (NO), through the H-NOX/HqsK quorum sensing pathway contributes to light production in V. harveyi through the LuxU/LuxO/LuxR quorum sensing pathway. In this study, we show that nitric oxide (NO) also regulates flagellar production and enhances biofilm formation. Our data suggest that V. harveyi is capable of switching between lifestyles to be able to adapt to changes in the environment. PMID:23965964

  4. 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.

  5. The Vibrio harveyi quorum-sensing system uses shared regulatory components to discriminate between multiple autoinducers

    PubMed Central

    Waters, Christopher M.; Bassler, Bonnie L.

    2006-01-01

    The quorum-sensing bacterium Vibrio harveyi produces and responds to three autoinducers (AIs), and this sensory information converges to control the expression of bioluminescence, biofilm formation, type III secretion (TTS), and protease production. The AIs are detected by cognate sensor histidine kinases that all relay phosphate to the shared response regulator LuxO. LuxO indirectly represses the master regulator of quorum sensing, LuxR, through the activation of multiple genes encoding small regulatory RNAs (called qrr genes for Quorum Regulatory RNA). Here we use differential fluorescence induction to identify 50 quorum-sensing-controlled promoters. Some promoters only showed significant responses in the simultaneous presence of all three AIs, while others displayed substantial responses to the individual AIs. A differential response to each AI input state was also observed for qrr and luxR expression and LuxR protein production. Individual cell analyses revealed that, in each case, all the bacteria in the population respond in unison to the various AI inputs. We propose that the V. harveyi quorum-sensing transition is not switch-like but rather operates in a graded manner, and that this signaling arrangement, which uses shared regulatory proteins, nonetheless provides V. harveyi a mechanism to respond uniquely to different AI input states. PMID:17015436

  6. Unique and conserved genome regions in Vibrio harveyi and related species in comparison with the shrimp pathogen Vibrio harveyi CAIM 1792.

    PubMed

    Espinoza-Valles, Iliana; Vora, Gary J; Lin, Baochuan; Leekitcharoenphon, Pimlapas; Gonzlez-Castillo, Adrin; Ussery, Dave; Hj, Lone; Gomez-Gil, Bruno

    2015-09-01

    Vibrio harveyi CAIM 1792 is a marine bacterial strain that causes mortality in farmed shrimp in north-west Mexico, and the identification of virulence genes in this strain is important for understanding its pathogenicity. The aim of this work was to compare the V. harveyi CAIM 1792 genome with related genome sequences to determine their phylogenic relationship and explore unique regions in silico that differentiate this strain from other V. harveyi strains. Twenty-one newly sequenced genomes were compared in silico against the CAIM 1792 genome at nucleotidic and predicted proteome levels. The proteome of CAIM 1792 had higher similarity to those of other V. harveyi strains (78%) than to those of the other closely related species Vibrio owensii (67%), Vibrio rotiferianus (63%) and Vibrio campbellii (59%). Pan-genome ORFans trees showed the best fit with the accepted phylogeny based on DNA-DNA hybridization and multi-locus sequence analysis of 11 concatenated housekeeping genes. SNP analysis clustered 34/38 genomes within their accepted species. The pangenomic and SNP trees showed that V. harveyi is the most conserved of the four species studied and V. campbellii may be divided into at least three subspecies, supported by intergenomic distance analysis. blastp atlases were created to identify unique regions among the genomes most related to V. harveyi CAIM 1792; these regions included genes encoding glycosyltransferases, specific type restriction modification systems and a transcriptional regulator, LysR, reported to be involved in virulence, metabolism, quorum sensing and motility. PMID:26198743

  7. Vibrio lentus protects gnotobiotic sea bass (Dicentrarchus labrax L.) larvae against challenge with Vibrio harveyi.

    PubMed

    Schaeck, M; Duchateau, L; Van den Broeck, W; Van Trappen, S; De Vos, P; Coulombet, C; Boon, N; Haesebrouck, F; Decostere, A

    2016-03-15

    Due to the mounting awareness of the risks associated with the use of antibiotics in aquaculture, treatment with probiotics has recently emerged as the preferred environmental-friendly prophylactic approach in marine larviculture. However, the presence of unknown and variable microbiota in fish larvae makes it impossible to disentangle the efficacy of treatment with probiotics. In this respect, the recent development of a germ-free culture model for European sea bass (Dicentrarchus labrax L.) larvae opened the door for more controlled studies on the use of probiotics. In the present study, 206 bacterial isolates, retrieved from sea bass larvae and adults, were screened in vitro for haemolytic activity, bile tolerance and antagonistic activity against six sea bass pathogens. Subsequently, the harmlessness and the protective effect of the putative probiotic candidates against the sea bass pathogen Vibrio harveyi were evaluated in vivo adopting the previously developed germ-free sea bass larval model. An equivalence trial clearly showed that no harmful effect on larval survival was elicited by all three selected probiotic candidates: Bacillus sp. LT3, Vibrio lentus and Vibrio proteolyticus. Survival of Vibrio harveyi challenged larvae treated with V. lentus was superior in comparison with the untreated challenged group, whereas this was not the case for the larvae supplemented with Bacillus sp. LT3 and V. proteolyticus. In this respect, our results unmistakably revealed the protective effect of V. lentus against vibriosis caused by V. harveyi in gnotobiotic sea bass larvae, rendering this study the first in its kind. PMID:26931390

  8. Draft Genome Sequences of the Fish Pathogen Vibrio harveyi Strains VH2 and VH5

    PubMed Central

    Castillo, Daniel; DAlvise, Paul; Middelboe, Mathias; Gram, Lone; Liu, Siyang; Kalatzis, Panos G.; Kokkari, Constantina

    2015-01-01

    Vibrio harveyi is an important marine pathogen that is responsible for vibriosis outbreaks in cultured fish and invertebrates worldwide. Here, we announce the draft genome sequences of V.harveyi strains VH2 and VH5, isolated from farmed juvenile Seriola dumerili during outbreaks of vibriosis in Crete, Greece. PMID:26383670

  9. Draft Genome Sequences of the Fish Pathogen Vibrio harveyi Strains VH2 and VH5.

    PubMed

    Castillo, Daniel; D'Alvise, Paul; Middelboe, Mathias; Gram, Lone; Liu, Siyang; Kalatzis, Panos G; Kokkari, Constantina; Katharios, Pantelis

    2015-01-01

    Vibrio harveyi is an important marine pathogen that is responsible for vibriosis outbreaks in cultured fish and invertebrates worldwide. Here, we announce the draft genome sequences of V.harveyi strains VH2 and VH5, isolated from farmed juvenile Seriola dumerili during outbreaks of vibriosis in Crete, Greece. PMID:26383670

  10. A small-RNA-mediated negative feedback loop controls quorum-sensing dynamics in Vibrio harveyi

    PubMed Central

    Tu, Kimberly C; Waters, Christopher M; Svenningsen, Sine L; Bassler, Bonnie L

    2008-01-01

    The bioluminescent marine bacterium Vibrio harveyi uses a cell-to-cell communication process called quorum sensing (QS) to co-ordinate behaviours in response to changes in population density. QS is accomplished through the secretion and detection of extracellular signalling molecules called autoinducers. At the centre of the V. harveyi QS circuit are five small regulatory RNAs called Qrr1–5 which destabilize the mRNA of luxR, encoding LuxR, the master transcriptional regulator of QS target genes. Here we show that LuxR directly activates transcription of qrr2, qrr3 and qrr4, leading to the rapid downregulation of luxR. The LuxR-binding sites in the promoters of qrr2, qrr3 and qrr4 were identified and mutated to determine the consequences of this regulatory loop on QS dynamics. Disruption of the loop delays the transition from high to low cell density, and more significantly, decreases the cell density at which the population reaches a quorum. Our results suggest that feedback is essential for optimizing the dynamics of the transitions between individual and group behaviours. PMID:18808382

  11. Characterization of phenotype variations of luminescent and non-luminescent variants of Vibrio harveyi wild type and quorum sensing mutants.

    PubMed

    Hong, N T X; Baruah, K; Vanrompay, D; Bossier, P

    2016-03-01

    Vibrio harveyi, a luminescent Gram-negative motile marine bacterium, is an important pathogen responsible for causing severe diseases in shrimp, finfish and molluscs leading to severe economic losses. Non-luminescent V. harveyi obtained by culturing luminescent strains under static and dark condition were reported to alter the levels of virulence factors and metalloprotease gene and luxR expression when compared to their luminescent variants. Presently, we conducted an in vitro study aiming at the characterization of virulence-related phenotypic traits of the wild-type V. harveyi BB120 strain and its isogenic quorum sensing mutants before and after switching to the non-luminescent status. We measured the production of caseinase, haemolysin and elastase and examined swimming motility and biofilm formation. Our results showed that switching from the bioluminescent to the non-luminescent state changed the phenotypic physiology or behaviour of V. harveyi resulting in alterations in caseinase and haemolytic activities, swimming motility and biofilm formation. The switching capacity was to a large extent independent from the quorum sensing status, in that quorum sensing mutants were equally capable of making the phenotypic switch. PMID:25865123

  12. Exposure to static magnetic field stimulates quorum sensing circuit in luminescent Vibrio strains of the Harveyi clade.

    PubMed

    Tal, 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 18C 0.1C 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

  13. 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

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

    NASA Astrophysics Data System (ADS)

    Alifano, P.; Nassisi, V.; Siciliano, M. V.; Tal, A.; Tredici, S. M.

    2011-05-01

    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.

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

    SciTech Connect

    Alifano, P.; Tala, A.; Tredici, S. M.; Nassisi, V.; Siciliano, M. V.

    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.

  16. Vibrio harveyi as a causative agent of the White Syndrome in tropical stony corals.

    PubMed

    Luna, Gian Marco; Bongiorni, Lucia; Gili, Claudia; Biavasco, Francesca; Danovaro, Roberto

    2010-02-01

    We investigated bacterial assemblages associated with corals displaying symptoms of the 'White Syndrome' (WS), a general term used for indicating the appearance of bands, spots or patches of tissue loss, which is devastating wide areas of tropical ecosystems worldwide. We collected WS-diseased (n = 15) and healthy (n = 15) corals from the natural reef (Indonesia, Indian Ocean) and from four large public aquaria. By using culture-dependent and culture-independent techniques, we found that a large fraction (73%) of the investigated WS events was associated with the presence of a high bacterial abundance and, specifically, of Vibrio spp. Vibrio harveyi, a pathogen of many marine organisms and recently involved in coral Yellow Band disease, was the most represented species, being recovered from five out of 15 diseased corals. In experimental infection assays, two V. harveyi strains, isolated from diseased corals, were inoculated on a total of 62 healthy colonies of Pocillopora damicornis. WS signs appeared in 57 corals, confirming the ability of V. harveyi strains to induce the disease. We conclude that V. harveyi is one of the coral pathogens involved in the appearance of WS. However, not all of the investigated WSs were associated to V. harveyi detection, nor to other Vibrio species (such as V. coralliilyticus), which supports the hypothesis that WS is not caused exclusively by Vibrio spp., but rather can have a multifactorial aetiology, or can represent a group of diseases caused by a variety of agents. Further investigations to identify specific virulence traits will contribute to the understanding of the role of V. harveyi in WS pathogenesis. PMID:23766006

  17. Gender-specific metabolic responses in hepatopancreas of mussel Mytilus galloprovincialis challenged by Vibrio harveyi.

    PubMed

    Liu, Xiaoli; Sun, Hushan; Wang, Yiyan; Ma, Mengwen; Zhang, Yuemei

    2014-10-01

    Mussel Mytilus galloprovincialis is a marine aquaculture shellfish and frequently studied in shellfish immunology. In this work, the gender-specific metabolic responses induced by Vibrio harveyi in hepatopancreas from M. galloprovincialis were characterized using NMR-based metabolomics. In details, V. harveyi challenge increased the levels of amino acids including (valine, leucine, isoleucine, threonine, alanine, arginine and tyrosine) and ATP, and decreased the level of glucose in male mussel hepatopancreas. In V. harveyi-challenged female mussel hepatopancreas, both threonine and AMP were significantly elevated, and choline, phoshphocholine, sn-glycero-3-phosphocholine, taurine, betaine and ATP were depleted. Obviously, only threonine was similarly altered to that in V. harveyi-challenged male mussel hepatopancreas. These findings confirmed the gender-specific metabolic responses in mussels challenged by V. harveyi. Overall, V. harveyi induced an enhanced energy demand through activated glycolysis and immune response indicated by increased BCAAs in male mussel hepatopancreas. In female mussel hepatopancreas, V. harveyi basically caused disturbances in both osmotic regulation and energy metabolism through the metabolic pathways of conversions of phosphocholine and ADP to choline and ATP, and sn-glycero-3-phosphocholine and H2O into choline and sn-glycerol 3-phosphate. The altered mRNA expression levels of related genes (Cu/Zn-SOD, HSP90, lysozyme and defensin) suggested that V. harveyi induced obvious oxidative and immune stresses in both male and female mussel hepatopancreas. This work demonstrated that V. harveyi could induce gender-specific metabolic responses in mussel M. galloprovincialis hepatopancreas using NMR-based metabolomics. PMID:25123832

  18. Determinants governing ligand specificity of the Vibrio harveyi LuxN quorum-sensing receptor

    PubMed Central

    Ke, Xiaobo; Miller, Laura C.; Bassler, Bonnie L.

    2014-01-01

    Summary Quorum sensing is a process of bacterial cell-cell communication that relies on the production, release, and receptor-driven detection of extracellular signal molecules called autoinducers. The quorum-sensing bacterium Vibrio harveyi exclusively detects the autoinducer N-((R)-3-hydroxybutanoyl)-L-homoserine lactone (3OH-C4 HSL) via the two-component receptor LuxN. To discover the principles underlying the exquisite selectivity LuxN has for its ligand, we identified LuxN mutants with altered specificity. LuxN uses three mechanisms to verify that the bound molecule is the correct ligand: In the context of the overall ligand-binding site, His210 validates the C3 modification, Leu166 surveys the chain-length, and a strong steady-state kinase bias imposes an energetic hurdle for inappropriate ligands to elicit signal transduction. Affinities for the LuxN Kinaseon and Kinaseoff states underpin whether a ligand will act as an antagonist or an agonist. Mutations that bias LuxN to the agonized, Kinaseoff, state are clustered in a region adjacent to the ligand-binding site, suggesting that this region acts as the switch that triggers signal transduction. Together, our analyses illuminate how a histidine sensor kinase differentiates between ligands and exploits those differences to regulate its signaling activity. PMID:25367076

  19. 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, Stphanie

    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 24days. 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

  20. Metabolic profiling of the tissue-specific responses in mussel Mytilus galloprovincialis towards Vibrio harveyi challenge.

    PubMed

    Liu, Xiaoli; Ji, Chenglong; Zhao, Jianmin; Wang, Qing; Li, Fei; Wu, Huifeng

    2014-08-01

    Mussel Mytilus galloprovincialis is a marine aquaculture shellfish distributing widely along the coast in north China. In this work, we studied the differential metabolic responses induced by Vibrio harveyi in digestive gland and gill tissues from M. galloprovincialis using NMR-based metabolomics. The differential metabolic responses in the two tissue types were detected, except the similarly altered taurine and betaine. These metabolic responses suggested that V. harveyi mainly induced osmotic disruption and reduced energy demand via the metabolic pathways of glucose synthesis and ATP/AMP conversion in mussel digestive gland. In mussel gill tissues, V. harveyi basically caused osmotic stress and possible reduced energy demand as shown by the elevated phosphocholine that is involved in one of the metabolic pathways of ATP synthesis from ADP and phosphocholine. The altered mRNA expression levels of related genes (superoxide dismutase with copper and zinc, heat shock protein 90, defensin and lysozyme) suggested that V. harveyi induced clear oxidative and immune stresses in both digestive gland and gill tissues. However, the mRNA expression levels of both lysozyme and defensin in digestive gland were more significantly up-regulated than those in gill from V. harveyi-challenged mussel M. galloprovincialis, meaning that the immune organ, digestive gland, was more sensitive than gill. Overall, our results indicated that V. harveyi could induce tissue-specific metabolic responses in mussel M. galloprovincialis. PMID:24911264

  1. Nucleotide sequence of the LuxC gene and the upstream DNA from the bioluminescent system of Vibrio harveyi.

    PubMed Central

    Miyamoto, C M; Graham, A F; Meighen, E A

    1988-01-01

    The nucleotide sequence of the luxC gene (1431 bp) and the upstream DNA (1049 bp) of the luminescent bacterium Vibrio harveyi has been determined. The luxC gene can be translated into a polypeptide of 55 kDa in excellent agreement with the molecular mass of the reductase polypeptide required for synthesis of the aldehyde substrate for the bioluminescent reaction. Analyses of codon usage showed a high frequency (1.9%) of the isoleucine codon, AUA, in the luxC gene compared to that found in Escherichia coli genes (0.2%) and its absence in the luxA, B and D genes. The low G/C content of the luxC gene and upstream DNA (38-39%) compared to that found in the other lux genes of V. harveyi (45%) was primarily due to a stretch of 500 nucleotides with only a 24% G/C content, extending from 200 bp inside lux C to 300 bp upstream. Moreover, an open reading frame did not extend for more than 48 codons between the luxC gene and 600 bp upstream at which point a gene transcribed in the opposite direction started. As the lux system in the luminescent bacterium, V. fischeri, contains a regulatory gene immediately upstream of luxC transcribed in the same direction, these results show that the organization and regulation of the lux genes have diverged in different luminescent bacteria. PMID:3347497

  2. 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

  3. Molecular variations in Vibrio alginolyticus and V. harveyi in shrimp-farming systems upon stress

    PubMed Central

    Santhyia, Anix Vivek; Mulloorpeedikayil, Rosalind George; Kollanoor, Riji John; Jeyaseelan, Prince M.J.

    2015-01-01

    A study was performed to investigate the genomic variations in the shrimp farm isolates of Vibrio alginolyticus and V. harveyi when the isolates were subjected to environmental stress. Samples of shrimps, water and sediment were collected from Southern Indian coastal shrimp farms. Vibrio isolates were biochemically identified and confirmed using 16S rDNA and gyrB gene specific PCR. The bacterial strains were genotyped by PCR fingerprinting using GTG(5) and IS (Insertion Sequence) primers. Seven strains each of V. alginolyticus and V. harveyi were subjected to 10 passages through trypticase soya broth (TSB), which contained different NaCl concentrations (3, 6 and 8%) and trypticase soya agar (TSA). V. alginolyticus was also passaged through TSB with a 12% NaCl concentration. PCR fingerprinting, which was performed on the strains that were passaged through different salt concentrations, confirmed that V. alginolyticus and V. harveyi could affect the genomic variations, depending on the environmental conditions of the culture. The study highlights the complex genotypic variations that occur in Vibrio strains of tropical aquatic environment because of varied environmental conditions, which result in genetic divergence and/or probable convergence. Such genetic divergence and/or convergence can lead to the organismal adaptive variation, which results in their ability to cause a productive infection in aquatic organisms or generation of new strains. PMID:26691457

  4. Molecular variations in Vibrio alginolyticus and V. harveyi in shrimp-farming systems upon stress.

    PubMed

    Santhyia, Anix Vivek; Mulloorpeedikayil, Rosalind George; Kollanoor, Riji John; Jeyaseelan, Prince M J

    2015-12-01

    A study was performed to investigate the genomic variations in the shrimp farm isolates of Vibrio alginolyticus and V. harveyi when the isolates were subjected to environmental stress. Samples of shrimps, water and sediment were collected from Southern Indian coastal shrimp farms. Vibrio isolates were biochemically identified and confirmed using 16S rDNA and gyrB gene specific PCR. The bacterial strains were genotyped by PCR fingerprinting using GTG(5) and IS (Insertion Sequence) primers. Seven strains each of V. alginolyticus and V. harveyi were subjected to 10 passages through trypticase soya broth (TSB), which contained different NaCl concentrations (3, 6 and 8%) and trypticase soya agar (TSA). V. alginolyticus was also passaged through TSB with a 12% NaCl concentration. PCR fingerprinting, which was performed on the strains that were passaged through different salt concentrations, confirmed that V. alginolyticus and V. harveyi could affect the genomic variations, depending on the environmental conditions of the culture. The study highlights the complex genotypic variations that occur in Vibrio strains of tropical aquatic environment because of varied environmental conditions, which result in genetic divergence and/or probable convergence. Such genetic divergence and/or convergence can lead to the organismal adaptive variation, which results in their ability to cause a productive infection in aquatic organisms or generation of new strains. PMID:26691457

  5. The Phosphorylation Flow of the Vibrio harveyi Quorum-Sensing Cascade Determines Levels of Phenotypic Heterogeneity in the Population

    PubMed Central

    Plener, Laure; Lorenz, Nicola; Reiger, Matthias; Ramalho, Tiago; Gerland, Ulrich

    2015-01-01

    ABSTRACT Quorum sensing (QS) is a communication process that enables a bacterial population to coordinate and synchronize specific behaviors. The bioluminescent marine bacterium Vibrio harveyi integrates three autoinducer (AI) signals into one quorum-sensing cascade comprising a phosphorelay involving three hybrid sensor kinases: LuxU; LuxO, an Hfq/small RNA (sRNA) switch; and the transcriptional regulator LuxR. Using a new set of V. harveyi mutants lacking genes for the AI synthases and/or sensors, we assayed the activity of the quorum-sensing cascade at the population and single-cell levels, with a specific focus on signal integration and noise levels. We found that the ratios of kinase activities to phosphatase activities of the three sensors and, hence, the extent of phosphorylation of LuxU/LuxO are important not only for the signaling output but also for the degree of noise in the system. The pools of phosphorylated LuxU/LuxO per cell directly determine the amounts of sRNAs produced and, consequently, the copy number of LuxR, generating heterogeneous quorum-sensing activation at the single-cell level. We conclude that the ability to drive the heterogeneous expression of QS-regulated genes in V. harveyi is an inherent feature of the architecture of the QS cascade. IMPORTANCE V. harveyi possesses one of the most complex quorum-sensing (QS) cascades known, using three different autoinducers (AIs) to control the induction of, e.g., bioluminescence, virulence factors, and biofilm and exoprotease production. We constructed various V. harveyi mutants to study the impact of each component and subsystem of the QS signaling cascade on QS activation at the population and single-cell levels. We found that the output was homogeneous only in the presence of all AIs. In the absence of any one AI, QS activation varied from cell to cell, resulting in phenotypic heterogeneity. This study elucidates a molecular design principle which enables a tightly integrated signaling cascade to control the expression of diverse phenotypes within a genetically homogeneous population. PMID:25755191

  6. Preparation of fatty-acylated derivatives of acyl carrier protein using Vibrio harveyi acyl-ACP synthetase.

    PubMed

    Shen, Z; Fice, D; Byers, D M

    1992-07-01

    A simple two-step purification of Vibrio harveyi fatty acyl-acyl carrier protein (acyl-ACP) synthetase, which is useful for the quantitative preparation and analysis of fatty-acylated derivatives of ACP, is described. Acyl-ACP synthetase can be partially purified from extracts of this bioluminescent bacterium by Cibacron blue chromatography and Sephacryl S-300 gel filtration and is stable for months at -20 degrees C in the presence of glycerol. Incubation of ACP from Escherichia coli with ATP and radiolabeled fatty acids (6 to 16 carbons in length) in the presence of the enzyme resulted in quantitative conversion to biologically active acylated derivatives. The enzyme reaction can be monitored by a filter disk assay to quantitate levels of ACP or by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography to detect ACP in cell extracts. With its broad fatty acid chain length specificity and optimal activity in mild nondenaturing buffers, the soluble V. harveyi acyl-ACP synthetase provides an attractive alternative to current chemical and enzymatic methods of acyl-ACP preparation and analysis. PMID:1514693

  7. 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

  8. 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

  9. 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.

  10. Identification of upregulated immune-related genes in Vibrio harveyi challenged Penaeus monodon postlarvae.

    PubMed

    Nayak, S; Singh, S K; Ramaiah, N; Sreepada, R A

    2010-09-01

    A subtracted cDNA library was constructed and analyzed to elucidate the response of Penaeus monodon postlarvae challenged with Vibrio harveyi. As many as 960 randomly selected cDNA fragments generated through suppression subtractive hybridization were single pass sequenced. Forty five genes and 20 hypothetical proteins were identified, a few being first reports from shrimps. The most abundant immune relevant genes were ferritin, hemocyanin, and TCTP (translationally controlled tumor protein) indicating their upregulation as also confirmed through qPCR. Post-infection qPCR analyses confirmed 2.04, 2.09, 3.28, 5.49, 6.47, and 11.63 fold rise respectively in ferritin, penaeidin, MnSOD, lysozyme, TCTP, and hemocyanin genes. These genes may be involved in the regulation of the host defense against V. harveyi. PMID:20580834

  11. 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 α-adrenergic antagonists or by the bacterial catecholamine receptor antagonist LED209, but not by β-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

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

    PubMed Central

    Rattanama, Pimonsri; Thompson, Janelle R.; Kongkerd, Natthawan; Srinitiwarawong, Kanchana; Vuddhakul, Varaporn; Mekalanos, John J.

    2012-01-01

    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, V. harveyi and V. vulnificus. We have used transposon mutagenesis to identify genes involved in the hemolytic activity of shrimp-pathogenic V. harveyi strain PSU3316. Out of 1,764 mutants screened, five mutants showed reduced hemolytic activity on sheep blood agar and exhibited virulence attenuation in shrimp (Litopenaeus vannamei). Mutants were identified by comparing transposon junction sequences to a draft of assembly of the PSU3316 genome. Surprisingly none of the disrupted open reading frames or gene neighborhoods contained genes annotated as hemolysins. The gene encoding RseB, a negative regulator of the sigma factor (σE), was interrupted in 2 out of 5 transposon mutants, in addition, the transcription factor CytR, a threonine synthetase, and an efflux-associated cytoplasmic protein were also identified. Knockout mutations introduced into the rpoE operon at the rseB gene exhibited low hemolytic activity in sheep blood agar, and were 3-to 7-fold attenuated for colonization in shrimp. Comparison of whole cell extracted proteins in the rseB mutant (PSU4030) to the wild-type by 2-D gel electrophoresis revealed 6 differentially expressed proteins, including two down-regulated porins (OmpC-like and OmpN) and an upregulated protease (DegQ) which have been associated with σE in other organisms. Our study is the first report linking hemolytic activity to the σE regulators in pathogenic Vibrio species and suggests expression of this virulence-linked phenotype is governed by multiple regulatory pathways within the V. harveyi. PMID:22384269

  13. Polycistronic mRNAs code for polypeptides of the Vibrio harveyi luminescence system

    SciTech Connect

    Miyamoto, C.M.; Graham, A.D.; Boylan, M.; Evans, J.F.; Hasel, K.W.; Meighen, E.A.; Graham, A.F.

    1985-03-01

    DNA coding for the ..cap alpha.. and ..beta.. subunits of Vibrio harveyi luciferase, the luxA and luxB genes, and the adjoining chromosomal regions on both sides of these genes (total of 18 kilobase pairs) was cloned into Escherichia coli. Using labeled DNA coding for the ..cap alpha.. subunit as a hybridization probe, the authors identified a set of polycistronic mRNAs (2.6, 4, 7, and 8 kilobases) by Northern blotting; the most prominent of these was the one 4 kilobases long. This set of mRNAs was induced during the development of bioluminescence in V. harveyi. Furthermore, the same set of mRNAs was synthesized in E. coli by a recombinant plasmid that contained a 12-kilobase pair length of V. harveyi DNA and expressed the genes for the luciferase subunits. A cloned DNA segment corresponding to the major 4-kilobase mRNA coded for the ..cap alpha.. and ..beta.. subunits of luciferase, as well as a 32,000-dalton protein upstream from these genes that could be specifically modified by acyl-coenzyme A and is a component of the bioluminescence system. V. harveyi mRNA that was hybridized to the released from cloned DNA encompassing the luxA and luxB genes was translated in vitro. Luciferase ..cap alpha.. and ..beta.. subunits and the 32,000-dalton polypeptide were detected among the products, along with 42,000- and 55,000-dalton polypeptides, which are encoded downstream from the lux genes and are thought to be involved in luminescence.

  14. Complete Genome Sequence of Virulence-Enhancing Siphophage VHS1 from Vibrio harveyi

    PubMed Central

    Khemayan, Krit; Prachumwat, Anuphap; Sonthayanon, Burachai; Intaraprasong, Aungkul; Sriurairatana, Siriporn

    2012-01-01

    Vibrio harveyi siphophage 1 (VHS1) is a tailed phage with an icosahedral head of approximately 66 nm in diameter and an unornamented, flexible tail of approximately 153 nm in length. When Vibrio harveyi 1114GL is lysogenized with VHS1, its virulence for the black tiger shrimp (Penaeus monodon) increases by more than 100 times, and this coincides with production of a toxin(s) associated with shrimp hemocyte agglutination. Curiously, the lysogen does not show increased virulence for the whiteleg shrimp (Penaeus [Litopenaeus] vannamei). Here we present and annotate the complete, circular genome of VHS1 (81,509 kbp; GenBank accession number JF713456). By software analysis, the genome contains 125 putative open reading frames (ORFs), all of which appear to be located on the same DNA strand, similar to the case for many other bacteriophages. Most of the putative ORFs show no significant homology to known sequences in GenBank. Notable exceptions are ORFs for a putative DNA polymerase and putative phage structural proteins, including a portal protein, a phage tail tape measure protein, and a phage head protein. The last protein was identified as a component of the species-specific toxin mixture described above as being associated with agglutination of hemocytes from P. monodon. PMID:22307287

  15. Unveiling the Metabolic Pathways Associated with the Adaptive Reduction of Cell Size During Vibrio harveyi Persistence in Seawater Microcosms.

    PubMed

    Kaberdin, Vladimir R; Montnchez, Itxaso; Parada, Claudia; Orruo, Maite; Arana, Ins; Barcina, Isabel

    2015-10-01

    Owing to their ubiquitous presence and ability to act as primary or opportunistic pathogens, Vibrio species greatly contribute to the diversity and evolution of marine ecosystems. This study was aimed at unveiling the cellular strategies enabling the marine gammaproteobacterium Vibrio harveyi to adapt and persist in natural aquatic systems. We found that, although V. harveyi incubation in seawater microcosm at 20C for 2weeks did not change cell viability and culturability, it led to a progressive reduction in the average cell size. Microarray analysis revealed that this morphological change was accompanied by a profound decrease in gene expression affecting the central carbon metabolism, major biosynthetic pathways, and energy production. In contrast, V. harveyi elevated expression of genes closely linked to the composition and function of cell envelope. In addition to triggering lipid degradation via the ?-oxidation pathway and apparently promoting the use of endogenous fatty acids as a major energy and carbon source, V. harveyi upregulated genes involved in ancillary mechanisms important for sustaining iron homeostasis, cell resistance to the toxic effect of reactive oxygen species, and recycling of amino acids. The above adaptation mechanisms and morphological changes appear to represent the major hallmarks of the initial V. harveyi response to starvation. PMID:25903990

  16. 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

  17. Flavonoids from Piper delineatum modulate quorum-sensing-regulated phenotypes in Vibrio harveyi.

    PubMed

    Martn-Rodrguez, Alberto J; Ticona, Juan C; Jimnez, Ignacio A; Flores, Ninoska; Fernndez, Jos J; Bazzocchi, Isabel L

    2015-09-01

    Quorum sensing (QS), or bacterial cell-to-cell communication, is a key process for bacterial colonization of substrata through biofilm formation, infections, and production of virulence factors. In an ongoing investigation of bioactive secondary metabolites from Piper species, four new flavonoids (1-4), along with five known ones (5-9) were isolated from the leaves of Piper delineatum. Their stereostructures were established by spectroscopic and spectrometric methods, including 1D and 2D NMR experiments, and comparison with data reported in the literature. The compounds were screened for their ability to interfere with QS signaling in the bacterial model Vibrio harveyi. Four compounds from this series (2, 3, 6, and 7) exhibited remarkable activity in the micromolar range, being compounds 3 and 7 particularly attractive since they did not affect bacterial growth. The results suggest that these flavonoids disrupt QS-mediated bioluminescence by interaction with elements downstream LuxO in the QS circuit of V. harveyi, and also, they exhibited a strong dose-dependent inhibition of biofilm formation. The present findings shed light on the QS inhibition mechanisms of flavonoids, underlining their potential applications. PMID:26070141

  18. Dynamics and Mechanism of A Quorum Sensing Network Regulated by Small RNAs in Vibrio Harveyi

    NASA Astrophysics Data System (ADS)

    Shen, Jian-Wei

    2011-03-01

    Bacterial quorum sensing (QS) has attracted much interests and it is an important process of cell communication. Recently, Bassler et al. studied the phenomena of QS regulated by small RNAs and the experimental data showed that small RNAs played important role in the QS of Vibrio harveyi and it can permit the fine-tuning of gene regulation and maintenance of homeostasis. According to MichaelisMenten kinetics and mass action law in this paper, we construct a mathematical model to investigate the mechanism induced QS by coexist of small RNA and signal molecular (AI) and show that there are periodic oscillation when the time delay and Hill coefficient exceed a critical value and the periodic oscillation produces the change of concentration and induces QS. These results are fit to the experimental results. In the meanwhile, we also get some theoretical value of Hopf Bifurcation on time deday. In addition, we also find this network is robust against noise.

  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 4C within 60days. 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. A sensitive fluorescence reporter for monitoring quorum sensing regulated protease production in Vibrio harveyi.

    PubMed

    Rajamani, Sathish; Sayre, Richard T

    2011-02-01

    Many bacteria produce and secrete proteases during host invasion and pathogenesis. Vibrio harveyi, an opportunistic pathogen of shrimp, is known to use a two-component quorum sensing (QS) mechanism for coordination of gene expression including protease secretion at high population densities. We examined the role of V. harveyi's QS signaling molecules, N-(3-hydroxybutanoyl)-L-homoserine lactone (AI-1) and the boron derivative of autoinducer-2 (BAI-2) in extracellular protease production. A fusion protein, M3CLPY (Rajamani et al., 2007), consisting of a large protease sensitive BAI-2 mutant receptor LuxP (~38kDa) flanked by two protease insensitive cyan and yellow variants of GFP (~28kDa each) was utilized as a substrate to detect secreted protease activity. The M3CLPY fusion, with the addition of wild-type V. harveyi (BB120) cell-free culture filtrate showed a time-dependent loss in fluorescence resonance energy transfer (FRET) associated with the cleavage of the LuxP linker protein and hence separation of the two fluorophores. This cleavage of LuxP linker protein leading to decreased FRET efficiency was further confirmed by immunoblotting using anti-GFP antibody. The addition of cell-free filtrates from strains defective in one or both of the two-component QS pathways: luxN(-) (defective in AI-1), luxS(-) (defective in BAI-2), and luxN(-)/luxS(-) (defective in both AI-1/BAI-2) showed differential levels of protease production. The observed protease activities were most pronounced in wild-type, followed by the AI-1 defective mutant (BB170) and the least for luxS(-) mutant (MM30) and luxN(-)/luxS(-) double mutant (MM32) strains. Incidentally, the lowest protease producing strains MM30 and MM32 were both defective in BAI-2 production. This observation was validated by addition of synthetic BAI-2 to MM30 and MM32 strains to restore protease production. Our results indicate that BAI-2 signaling in the two-component QS pathway plays the key role in regulating extracellular protease production in V. harveyi. PMID:21129419

  1. Immunological study of the outer membrane proteins of Vibrio harveyi: insights that link immunoprotectivity to interference with bacterial infection.

    PubMed

    Yu, Lan-ping; Hu, Yong-hua; Sun, Bo-guang; Sun, Li

    2013-10-01

    Vibrio harveyi is a bacterial pathogen that affects marine vertebrates and invertebrates. In this study, we identified 13 outer membrane proteins (OMPs) from a pathogenic V. harveyi strain and analyzed their immunological properties. Invivo immunogenicity analysis showed that antibodies specific to recombinant proteins of the 13 OMPs were detected in the antiserum of V. harveyi-infected rat. When used as subunit vaccines to immunize Japanese flounder (Paralichthys olivaceus), all OMPs were able to elicit specific serum antibody production in the vaccinated fish; however, only two OMPs (OMP173 and OMP214) induced high levels (>70%) of relative percent survival. Pre-incubation of V. harveyi with the antisera of protective OMPs significantly impaired bacterial infectivity against peripheral blood leukocytes (PBL), whereas the antisera of non-protective OMPs had no apparent effect on infection. OMP173 antibodies could bind whole V. harveyi cells and exhibit bactericidal effect in a complement-dependent manner. Passive immunization showed that fish received OMP173 antiserum before being infected with V. harveyi exhibited significantly reduced mortality rate and lower bacterial loads in liver, spleen, and kidney. Finally, treatment of FG cells with OMP173 prior to V. harveyi infection protected the cells from bacterial invasion to a significant extent. Take together, these results indicate that two of the examined OMPs induce protective immunity through production of specific antibodies that block bacterial invasion, and that one OMP is likely to be involved in host cell interaction during the infection process. Thus, the immunoprotectivity of the OMPs is probably associated with functional participations of the OMPs in bacterial infection. PMID:23932987

  2. 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

  3. The early stages of the immune response of the European abalone Haliotis tuberculata to a Vibrio harveyi infection.

    PubMed

    Cardinaud, Marion; Dheilly, Nolwenn M; Huchette, Sylvain; Moraga, Dario; Paillard, Christine

    2015-08-01

    Vibrio harveyi is a marine bacterial pathogen responsible for episodic abalone mortalities in France, Japan and Australia. In the European abalone, V. harveyi invades the circulatory system in a few hours after exposure and is lethal after 2 days of infection. In this study, we investigated the responses of European abalone immune cells over the first 24 h of infection. Results revealed an initial induction of immune gene expression including Rel/NF-kB, Mpeg and Clathrin. It is rapidly followed by a significant immuno-suppression characterized by reduced cellular hemocyte parameters, immune response gene expressions and enzymatic activities. Interestingly, Ferritin was overexpressed after 24 h of infection suggesting that abalone attempt to counter V. harveyi infection using soluble effectors. Immune function alteration was positively correlated with V. harveyi concentration. This study provides the evidence that V. harveyi has a hemolytic activity and an immuno-suppressive effect in the European abalone. PMID:25766281

  4. Characterization of four lytic transducing bacteriophages of luminescent Vibrio harveyi isolated from shrimp (Penaeus monodon) hatcheries.

    PubMed

    Thiyagarajan, Sanjeevi; Chrisolite, Bagthasingh; Alavandi, Shankar V; Poornima, Modem; Kalaimani, Natarajan; Santiago, T Chinnappan

    2011-12-01

    Four lytic bacteriophages designated as ?Vh1, ?Vh2, ?Vh3, and ?Vh4 were isolated from commercial shrimp hatcheries, possessing broad spectrum of infectivity against luminescent Vibrio harveyi isolates, considering their potential as biocontrol agent of luminescent bacterial disease in shrimp hatcheries, and were characterized by electron microscopy, genomic analysis, restriction enzyme analysis (REA), and pulsed-field gel electrophoresis (PFGE). Three phages ?Vh1, ?Vh2, and ?Vh4 had an icosahedral head of 60-115 nm size with a long, noncontractile tail of 130-329 1-17 nm, belonged to the family Siphoviridae. ?Vh3 had an icosahedral head (72 5 nm) with a short tail (27 12 nm) and belonged to Podoviridae. REA with DraI and PFGE of genomic DNA digested with ScaI and XbaI and cluster analysis of their banding patterns indicated that ?Vh3 was distinct from the other three siphophages. PFGE-based genome mean size of the four bacteriophages ?Vh1, ?Vh2, ?Vh3, and ?Vh4 was estimated to be about 85, 58, 64, and 107 kb, respectively. These phages had the property of generalized transduction as demonstrated by transduction with plasmid pHSG 396 with frequencies ranging from 4.1 10(-7) to 2 10(-9) per plaque-forming unit, suggesting a potential ecological role in gene transfer among aquatic vibrios. PMID:22092866

  5. Bacteriophage adenine methyltransferase: a life cycle regulator? Modelled using Vibrio harveyi myovirus like.

    PubMed

    Bochow, S; Elliman, J; Owens, L

    2012-11-01

    The adenine methyltransferase (DAM) gene methylates GATC sequences that have been demonstrated in various bacteria to be a powerful gene regulator functioning as an epigenetic switch, particularly with virulence gene regulation. However, overproduction of DAM can lead to mutations, giving rise to variability that may be important for adaptation to environmental change. While most bacterial hosts carry a DAM gene, not all bacteriophage carry this gene. Currently, there is no literature regarding the role DAM plays in life cycle regulation of bacteriophage. Vibrio campbellii strain 642 carries the bacteriophage Vibrio harveyi myovirus like (VHML) that has been proven to increase virulence. The complete genome sequence of VHML bacteriophage revealed a putative adenine methyltransferase gene. Using VHML, a new model of phage life cycle regulation, where DAM plays a central role between the lysogenic and lytic states, will be hypothesized. In short, DAM methylates the rha antirepressor gene and once methylation is removed, homologous CI repressor protein becomes repressed and non-functional leading to the switching to the lytic cycle. Greater understanding of life cycle regulation at the genetic level can, in the future, lead to the genesis of chimeric bacteriophage with greater control over their life cycle for their safe use as probiotics within the aquaculture industry. PMID:22681538

  6. Chemotaxis in marine bacterium Vibrio alginolyticus

    NASA Astrophysics Data System (ADS)

    Xie, Li

    We investigated the motility pattern and chemotaxis system of the polarly flagellated marine bacterium Vibrio alginolyticus. V. alginolyticus executes 3-step (run-reverse-flick) cycles which are distinctively different from the 2-step (run-tumble) pattern of Escherichia coli. This marine bacterium backtracks its forward swimming path and randomizes its moving direction by flicking its flagellum at the end of the backward swimming interval. V. alginolyticus has a similar chemotaxis system as E. coli, and our study showed that their chemotaxis networks respond to chemical cues in the same manner. However, at contrast to E. coli, in which the motor bias is regulate by the chemotaxis network, in V. alginolyticus, the switching rates of the flagellar motor is modulated so that swimming intervals in a favorable direction can be lengthened regardless of the motor rotation direction. As a result, despite their different motility patterns, both E. coli and V. alginolyticus use a biased random walk to migrate toward a nutrient source. To understand the effect of motility patterns on chemotaxis capacity, master equations similar to convection-diffusion equations were developed to describe the motion of these two bacteria in a chemical profile. It was found that by adopting the run-reverse-flick motility pattern, a 3-step swimmer has the same drift velocity but its diffusivity is reduced by half compared to a 2-step swimmer. As a result of the smaller diffusivity, the former localizes better around a nutrient source but does not explore as efficiently as the latter. We thus speculate that the 3-step motility pattern suits better for the marine environment where searching is unproductive and it is more important to exploit an existing, though transient, resource.

  7. A mathematical model and quantitative comparison of the small RNA circuit in the Vibrio harveyi and Vibrio cholerae quorum sensing systems

    NASA Astrophysics Data System (ADS)

    Hunter, G. A. M.; Guevara Vasquez, F.; Keener, J. P.

    2013-08-01

    Quorum sensing is the process by which bacteria regulate their gene expression based on the local cell-population density. The quorum sensing systems of Vibrio harveyi and Vibrio cholerae are comprised of a phosphorelay cascade coupled to a small RNA (sRNA) circuit. The sRNA circuit contains multiple quorum regulated small RNA (Qrr) that regulate expression of the homologous master transcriptional regulators LuxR (in V. harveyi) and HapR (in V. cholerae). Their quorum sensing systems are topologically similar and homologous thereby making it difficult to understand why repression of HapR is more robust than LuxR to changes in Qrr. In this work we formulate and parameterize a novel mathematical model of the V. harveyi and V. cholerae sRNA circuit. We parameterize the model by fitting it to a variety of empirical data from both species. We show that we can distinguish all of the parameters and that the parameterizations (one for each species) are robust to errors in the data. We then use our model to propose some experiments to identify and explain kinetic differences between the species. We find that V. cholerae Qrr are more abundant and more sensitive to changes in LuxO than V. harveyi Qrr and argue that this is why expression of HapR is more robust than LuxR to changes in Qrr.

  8. 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

    Hundenborn, Jrg; Thurig, Steffi; Kommerell, Mechthild; Haag, Heike; Nolte, Oliver

    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

  9. 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, Jrg; 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

  10. Probing the Catalytic Mechanism of Vibrio harveyi GH20 β-N-Acetylglucosaminidase by Chemical Rescue

    PubMed Central

    Meekrathok, Piyanat; Suginta, Wipa

    2016-01-01

    Background Vibrio harveyi GH20 β-N-acetylglucosaminidase (VhGlcNAcase) is a chitinolytic enzyme responsible for the successive degradation of chitin fragments to GlcNAc monomers, activating the onset of the chitin catabolic cascade in marine Vibrios. Methods Two invariant acidic pairs (Asp303-Asp304 and Asp437-Glu438) of VhGlcNAcase were mutated using a site-directed mutagenesis strategy. The effects of these mutations were examined and the catalytic roles of these active-site residues were elucidated using a chemical rescue approach. Enhancement of the enzymic activity of the VhGlcNAcase mutants was evaluated by a colorimetric assay using pNP-GlcNAc as substrate. Results Substitution of Asp303, Asp304, Asp437 or Glu438 with Ala/Asn/Gln produced a dramatic loss of the GlcNAcase activity. However, the activity of the inactive D437A mutant was recovered in the presence of sodium formate. Our kinetic data suggest that formate ion plays a nucleophilic role by mimicking the β-COO-side chain of Asp437, thereby stabilizing the reaction intermediate during both the glycosylation and the deglycosylation steps. Conclusions Chemical rescue of the inactive D437A mutant of VhGlcNAcase by an added nucleophile helped to identify Asp437 as the catalytic nucleophile/base, and hence its acidic partner Glu438 as the catalytic proton donor/acceptor. General Significance Identification of the catalytic nucleophile of VhGlcNAcases supports the proposal of a substrate-assisted mechanism of GH20 GlcNAcases, requiring the catalytic pair Asp437-Glu438 for catalysis. The results suggest the mechanistic basis of the participation of β-N-acetylglucosaminidase in the chitin catabolic pathway of marine Vibrios. PMID:26870945

  11. Pathogenic Vibrio harveyi, in contrast to non-pathogenic strains, intervenes with the p38 MAPK pathway to avoid an abalone haemocyte immune response.

    PubMed

    Travers, Marie-Agnès; Le Bouffant, Ronan; Friedman, Carolyn S; Buzin, Florence; Cougard, Bertrand; Huchette, Sylvain; Koken, Marcel; Paillard, Christine

    2009-01-01

    Vibrio harveyi is a marine bacterial pathogen responsible for episodic abalone epidemics associated with massive mortalities in France, Japan, and Australia. The aim of this study was the understanding of a possible role of the p38 MAPK in abalone haemocyte responses towards this bacterium. First, the pathogenicity of different V. harveyi strains was compared in both immersion and injection trials, and clear differences were detected. The three strains, ORM4, 04/092, and 05/053, all isolated from moribund abalone, induced up to 80% mortalities in immersion or injection challenges (LD(50) (ORM4) = 2.5 x 10(2) CFU animal(-1)). The two strains, LMG 4044T and LMG 7890 were non-pathogenic towards abalone in immersion trials, and needed very high numbers for killing by intramuscular injections (LD(50) = 8.9 x 10(4) and 1.6 x 10(5) CFU animal(-1), respectively). To start unraveling the mechanism explaining these differences, the p38-MAPK, a keyplayer in antimicrobial immune response, was studied. The non-pathogenic strain, LMG 7890 can be eliminated by abalone haemocytes and induces haemocyte phagocytosis and high ROS production. With different concentrations of a p38-specific inhibitor, SB203580, p38 implication was shown. This inhibitor reduced phagocytosis and ROS induction leading to LMG 7890 proliferation. In the case of the pathogenic ORM4 which can not be eliminated by abalone haemocytes, no phagocytosis and ROS production was induced, and a retarded p38 activation was observed. Taken together, our results suggest that p38 MAPK modulation may be one of the ways of virulent V. harveyi to attack its host and escape abalone immune response. PMID:19058134

  12. Bacterial dynamics in intestines of the black tiger shrimp and the Pacific white shrimp during Vibrio harveyi exposure.

    PubMed

    Rungrassamee, Wanilada; Klanchui, Amornpan; Maibunkaew, Sawarot; Karoonuthaisiri, Nitsara

    2016-01-01

    The intestinal microbiota play important roles in health of their host, contributing to maintaining the balance and resilience against pathogen. To investigate effects of pathogen to intestinal microbiota, the bacterial dynamics upon a shrimp pathogen, Vibrio harveyi, exposures were determined in two economically important shrimp species; the black tiger shrimp (BT) and the Pacific white shrimp (PW). Both shrimp species were reared under the same diet and environmental conditions. Shrimp survival rates after the V. harveyi exposure revealed that the PW shrimp had a higher resistance to the pathogen than the BT shrimp. The intestinal bacterial profiles were determined by denaturing gradient gel electrophoresis (DGGE) and barcoded pyrosequencing of the 16S rRNA sequences under no pathogen challenge control and under pathogenic V. harveyi challenge. The DGGE profiles showed that the presence of V. harveyi altered the intestinal bacterial patterns in comparison to the control in BT and PW intestines. This implies that bacterial balance in shrimp intestines was disrupted in the presence of V. harveyi. The barcoded pyrosequencing analysis showed the similar bacterial community structures in intestines of BT and PW shrimp under a normal condition. However, during the time course exposure to V. harveyi, the relative abundance of bacteria belong to Vibrio genus was higher in the BT intestines at 12h after the exposure, whereas relative abundance of vibrios was more stable in PW intestines. The principle coordinates analysis based on weighted-UniFrac analysis showed that intestinal bacterial population in the BT shrimp lost their ability to restore their bacterial balance during the 72-h period of exposure to the pathogen, while the PW shrimp were able to reestablish their bacterial population to resemble those seen in the unexposed control group. This observation of bacterial disruption might correlate to different mortality rates observed between the two shrimp species. Our findings provide evidence of intestinal bacterial population altered by a presence of the pathogen in shrimp intestines and intestinal bacterial stability might provide colonization resistance against the invading pathogen in the host shrimp. Hence, intestinal microbial ecology management may potentially contribute to disease prevention in aquaculture. PMID:26585302

  13. Summer immune depression associated with increased susceptibility of the European abalone, Haliotis tuberculata to Vibrio harveyi infection.

    PubMed

    Travers, Marie-Agnès; Le Goïc, Nelly; Huchette, Sylvain; Koken, Marcel; Paillard, Christine

    2008-12-01

    Haliotis tuberculata mortality outbreaks have occurred in France since 1998 and were attributed to a pathogenic Vibrio harveyi. These mortalities were recorded in September, a month with abalone reproduction and characterised by high seawater temperatures. The importance of gonadal maturation and temperature increase on abalone immunity and susceptibility to V. harveyi infection needed to be clarified. Therefore, an immune survey analyzing a large panel of parameters was performed from June to September 2007 on abalone from the Bay of Brest. The data obtained were put in relation with abalone reproductive status and its susceptibility to V. harveyi. Most parameters showed clear patterns from early to late summer and during gametogenesis, phagocytosis and phenoloxidase activity were reduced, whereas basal reactive oxygen species production and agglutination titres were significantly increased. Total haemocyte counts went up after the partial spawning event at the end of June, and cell complexity diminished. Using a Principal Component Analysis, the "haemolymph profile" was shown to decrease in parallel with spawning and gonadal maturation processes, and reached a minimum just after total spawning. A significant correlation between this "haemolymph profile" and disease susceptibility allowed us to establish for the first time in abalone, a clear concordance between maturation and spawning processes, immune status and abalone susceptibility to V. harveyi. PMID:18786640

  14. Identification of Vibrio harveyi isolated from diseased Asian seabass Lates calcarifer by use of 16S ribosomal DNA sequencing.

    PubMed

    Ransangan, Julian; Mustafa, Saleem

    2009-09-01

    The grow out of Asian seabass Lates calcarifer in marine net-cages is a popular aquaculture activity in Malaysia. Production of this species is greatly affected by the occurrence of vibriosis, which causes heavy mortality. Generally, young fish are more susceptible; they exhibit anorexia and skin darkening, followed by heavy mortality. The acutely affected older fish may also exhibit bloody lesions around the anus and the base of the fins. Twenty-one bacterial isolates obtained from internal organs (kidney, heart, spleen and liver) of the affected specimens were subjected to phenotypic characterization, testing for antibiotic susceptibility, and 16S ribosomal DNA sequencing. The sequencing result showed that all of the bacterial isolates belonged to Vibrio harveyi. The phenotypic characterization, however, identified 4 of the bacterial isolates as V. harveyi, 16 as V. parahaemolyticus, and 1 as V. alginolyticus. These findings suggest that biochemical features alone cannot be reliably used to identify bacterial pathogens, including V. harveyi, in aquaculture. Antibiotic susceptibility assays showed that some antibiotics, including oxytetracycline, nitrofurantoin, furazolidone, streptomycin, sulfamethoxazole, chloramphenicol, nalidixic acid, and oxolinic acid were effective against V. harveyi. Considering the side effects of these antibiotics, however, their use is not recommended in the aquaculture of Asian seabass. PMID:20043399

  15. Duplication of Hemolysin Genes in a Virulent Isolate of Vibrio harveyi

    PubMed Central

    Zhang, X.-H.; Meaden, P. G.; Austin, B.

    2001-01-01

    Vibrio harveyi VIB 645, which is very pathogenic towards salmonids and produces extracellular product with a high titer of hemolytic activity towards fish erythrocytes, was found to contain two closely related hemolysin genes (designated vhhA and vhhB), whereas the majority of strains examined (11 of 13) carried only a single hemolysin gene. Both genes from VIB 645 were cloned and sequenced. The open reading frames (ORFs) of vhhA and vhhB shared a high level of identity (98.8%) and were predicted to encode identical polypeptides comprising 418 amino acid residues. The VHH protein shows homology to the lecithinase of V. mimicus and V. cholerae. Transformants of Escherichia coli containing the ORF of either vhhA or vhhB displayed weak hemolytic activity in rainbow trout blood agar. The hemolytic activity was very high when the ORF of vhhB was cloned in E. coli together with the native promoter. Surprisingly, the level of vhh-specific RNA transcript produced by VIB 645 was found to be very low. We conclude that the hemolytic phenotype of VIB 645 is not due to increased expression of one or both copies of the vhh gene. PMID:11425736

  16. Immunological evaluation of Vibrio alginolyticus, Vibrio harveyi, Vibrio vulnificus and infectious spleen and kidney necrosis virus (ISKNV) combined-vaccine efficacy in Epinephelus coioides.

    PubMed

    Huang, Zhijian; Tang, Jingjing; Li, Mei; Fu, Yacheng; Dong, Chuanfu; Zhong, Jiang F; He, Jianguo

    2012-11-15

    Combined vaccines are immunological products intended for immunization against multifactorial infectious diseases caused by different types or variants of pathogens. In this study, the effectiveness of Vibrio alginolyticus (Va), Vibrio harveyi (Vh), Vibrio vulnificus (Vv) and infectious spleen and kidney necrosis virus (ISKNV), an iridovirus, combined-vaccine (Vibrio and ISKNV combined vaccines, VICV), Va+Vh+Vv inactive vaccine (VIV) and ISKNV whole cell inactive vaccine (IWCIV) in Epinephelus coioides were evaluated using various immunological parameters including antibody titer, serum lysozyme activity (LA), respiratory burst (RB) activity, bactericidal activity (BA) and relative percentage survival (RPS). E. coioides immunized with VICV and challenged with Va+Vh+Vv+ISKNV had an RPS of 80%. The RPS was 73.3% in E. coioides immunized with VIV and challenged with Va+Vh+Vv. E. coioides immunized with IWCIV and challenged with ISKNV had an RPS of 69.6%. Serum LA in the vaccinated group was significantly higher than the control group on days 21 and 28 post-vaccination (P<0.01). The RB activity of head kidney cells in the vaccinated group was significantly higher (P<0.01) compared to that in the control group. However, RB activity of spleen cells in the vaccinated group and the control group were not significantly different (P>0.05). After immunization with VICV, BA values of blood leucocytes and head kidney cells increased significantly more than spleen cells. BA value of blood leucocytes was higher than that in head kidney cells. There were distinct difference between BA values in head kidney cells and in spleen cells (P<0.05) as well as between BA value of blood leucocytes and head kidney cells (P<0.01). E. coioides vaccinated with VICV have significantly higher antibody levels than control groupers (P<0.01). Our study suggests that the VICV candidate can effectively protect groupers against multiple bacterial and viral pathogens. PMID:23010220

  17. Involvement of the cgtA gene function in stimulation of DNA repair in Escherichia coli and Vibrio harveyi.

    PubMed

    Zielke, Ryszard; Sikora, Aleksandra; Dutkiewicz, Rafa?; Wegrzyn, Grzegorz; Czyz, Agata

    2003-07-01

    CgtA is a member of the Obg/Gtp1 subfamily of small GTP-binding proteins. CgtA homologues have been found in various prokaryotic and eukaryotic organisms, ranging from bacteria to humans. Nevertheless, despite the fact that cgtA is an essential gene in most bacterial species, its function in the regulation of cellular processes is largely unknown. Here it has been demonstrated that in two bacterial species, Escherichia coli and Vibrio harveyi, the cgtA gene product enhances survival of cells after UV irradiation. Expression of the cgtA gene was found to be enhanced after UV irradiation of both E. coli and V. harveyi. Moderate overexpression of cgtA resulted in higher UV resistance of E. coli wild-type and dnaQ strains, but not in uvrA, uvrB, umuC and recA mutant hosts. Overexpression of the E. coli recA gene in the V. harveyi cgtA mutant, which is very sensitive to UV light, restored the level of survival of UV-irradiated cells to the levels observed for wild-type bacteria. Moreover, the basal level of the RecA protein was lower in a temperature-sensitive cgtA mutant of E. coli than in the cgtA(+) strain, and contrary to wild-type bacteria, no significant increase in recA gene expression was observed after UV irradiation of this cgtA mutant. Finally, stimulation of uvrB gene transcription under these conditions was impaired in the V. harveyi cgtA mutant. All these results strongly suggest that the cgtA gene product is involved in DNA repair processes, most probably by stimulation of recA gene expression and resultant activation of RecA-dependent DNA repair pathways. PMID:12855728

  18. Contrasting inter- and intraspecies recombination patterns in the "Harveyi clade" vibrio collected over large spatial and temporal scales.

    PubMed

    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

  19. 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

  20. The Vibrio harveyi bioassay used routinely to detect AI-2 quorum sensing inhibition is confounded by inconsistent normalization across marine matrices.

    PubMed

    Blair, Walter M; Doucette, Gregory J

    2013-03-01

    The Vibrio harveyi autoinducer-2 (AI-2) bioassay is used routinely to screen for inhibition of the AI-2 quorum sensing system. The present study utilizes three well-described bacterial strains to demonstrate that inconsistent normalization across matrices undermines the assay's use in screening marine samples for AI-2 inhibition. PMID:23305926

  1. Microcalorimetric Measurements of Glucose Metabolism by Marine Bacterium Vibrio alginolyticus

    PubMed Central

    Gordon, Andrew S.; Millero, Frank J.; Gerchakov, Sol M.

    1982-01-01

    Microcalorimetric measurements of heat production from glucose by Vibrio alginolyticus were made to assess the viability of calorimetry as a technique for studying the metabolism of marine bacteria at organic nutrient concentrations found in marine waters. The results show that the metabolism of glucose by this bacterium can be measured by calorimetry at submicromolar concentrations. A linear correlation between glucose concentration and total heat production was observed over a concentration range of 8 mM to 0.35 ?M. It is suggested that these data indicate a constant efficiency of metabolism for this bacterium over the wide range of glucose concentrations studied. PMID:16346131

  2. Expression and Quorum Sensing Regulation of Type III Secretion System Genes of Vibrio harveyi during Infection of Gnotobiotic Brine Shrimp

    PubMed Central

    Ruwandeepika, H. A. Darshanee; Karunasagar, Indrani; Bossier, Peter; Defoirdt, Tom

    2015-01-01

    Type III secretion systems enable pathogens to inject their virulence factors directly into the cytoplasm of the host cells. The type III secretion system of Vibrio harveyi, a major pathogen of aquatic organisms and a model species in quorum sensing studies, is repressed by the quorum sensing master regulator LuxR. In this study, we found that during infection of gnotobiotic brine shrimp larvae, the expression levels of three type III secretion operons in V. harveyi increased within the first 12h after challenge and decreased again thereafter. The in vivo expression levels were highest in a mutant with a quorum sensing system that is locked in low cell density configuration (minimal LuxR levels) and lowest in a mutant with a quorum sensing system that is locked in the high cell density configuration (maximal LuxR levels), which is consistent with repression of type III secretion by LuxR. Remarkably, in vivo expression levels of the type III secretion system genes were much (> 1000 fold) higher than the in vitro expression levels, indicating that (currently unknown) host factors significantly induce the type III secretion system. Given the fact that type III secretion is energy-consuming, repression by the quorum sensing master regulators might be a mechanism to save energy under conditions where it does not provide an advantage to the cells. PMID:26636765

  3. Expression and Quorum Sensing Regulation of Type III Secretion System Genes of Vibrio harveyi during Infection of Gnotobiotic Brine Shrimp.

    PubMed

    Ruwandeepika, H A Darshanee; Karunasagar, Indrani; Bossier, Peter; Defoirdt, Tom

    2015-01-01

    Type III secretion systems enable pathogens to inject their virulence factors directly into the cytoplasm of the host cells. The type III secretion system of Vibrio harveyi, a major pathogen of aquatic organisms and a model species in quorum sensing studies, is repressed by the quorum sensing master regulator LuxR. In this study, we found that during infection of gnotobiotic brine shrimp larvae, the expression levels of three type III secretion operons in V. harveyi increased within the first 12h after challenge and decreased again thereafter. The in vivo expression levels were highest in a mutant with a quorum sensing system that is locked in low cell density configuration (minimal LuxR levels) and lowest in a mutant with a quorum sensing system that is locked in the high cell density configuration (maximal LuxR levels), which is consistent with repression of type III secretion by LuxR. Remarkably, in vivo expression levels of the type III secretion system genes were much (> 1000 fold) higher than the in vitro expression levels, indicating that (currently unknown) host factors significantly induce the type III secretion system. Given the fact that type III secretion is energy-consuming, repression by the quorum sensing master regulators might be a mechanism to save energy under conditions where it does not provide an advantage to the cells. PMID:26636765

  4. Profiling of a few immune responsive genes expressed in postlarvae of Fenneropenaeus indicus challenged with Vibrio harveyi D3.

    PubMed

    Nayak, S; Ajay, K M; Ramaiah, N; Meena, Ram M; Sreepada, R A

    2011-06-01

    We identified 38 genes and eight hypothetical proteins by sequencing of 1200 clones from a Vibrio harveyi challenged Fenneropenaeus indicus subtracted cDNA library. Based on physiological roles and functions these genes were categorized into 10 groups with ?29% of the sequences having no matches in the databases. Immune related transcripts in the library were carboxypeptidase B, ferritin, translationally controlled tumor proteins (TCTP), hemocyanin, chitinase and serine carboxy peptidase. Remarkably, qPCR results imply 4.15, 3.45 and 1.86-fold rises in expression of ferritin, TCTP and hemocyanin transcripts respectively. Additionally, minor upregulation of other immune relevant genes lectin, penaeidin, crustin, MnSOD was observed in the challenged postlarvae. PMID:21515280

  5. Assimilable Organic Carbon (AOC) in Soil Water Extracts Using Vibrio harveyi BB721 and Its Implication for Microbial Biomass

    PubMed Central

    Ma, Jincai; Ibekwe, A. Mark; Leddy, Menu; Yang, Ching-Hong; Crowley, David E.

    2012-01-01

    Assimilable organic carbon (AOC) is commonly used to measure the growth potential of microorganisms in water, but has not yet been investigated for measuring microbial growth potential in soils. In this study, a simple, rapid, and non-growth based assay to determine AOC in soil was developed using a naturally occurring luminous strain Vibrio harveyi BB721 to determine the fraction of low molecular weight organic carbon in soil water extract. Calibration of the assay was achieved by measuring the luminescence intensity of starved V. harveyi BB721 cells in the late exponential phase with a concentration range from 0 to 800 g l?1 glucose (equivalent to 016.0 mg glucose C kg?1 soil) with the detection limit of 10 g l?1 equivalent to 0.20 mg glucose C kg?1 soil. Results showed that bioluminescence was proportional to the concentration of glucose added to soil. The luminescence intensity of the cells was highly pH dependent and the optimal pH was about 7.0. The average AOC concentration in 32 soils tested was 2.92.2 mg glucose C kg?1. Our data showed that AOC levels in soil water extracts were significantly correlated (P<0.05) with microbial biomass determined as microbial biomass carbon, indicating that the AOC concentrations determined by the method developed might be a good indicator of soil microbial biomass. Our findings provide a new approach that may be used to determine AOC in environmental samples using a non-growth bioluminescence based assay. Understanding the levels of AOC in soil water extract provides new insights into our ability to estimate the most available carbon pool to bacteria in soil that may be easily assimilated into cells for many metabolic processes and suggest possible the links between AOC, microbial regrowth potential, and microbial biomass in soils. PMID:22679477

  6. Description of a novel marine bacterium, Vibrio hyugaensis sp. nov., based on genomic and phenotypic characterization.

    PubMed

    Urbanczyk, Yoshiko; Ogura, Yoshitoshi; Hayashi, Tetsuya; Urbanczyk, Henryk

    2015-07-01

    Three luminous bacteria strains have been isolated from seawater samples collected in the coastal regions of the Miyazaki prefecture in Japan. Analysis of the 16S rRNA gene sequences identified the three strains as members of the genus Vibrio (Vibrionaceae, Gammaproteobacteria), closely related to bacteria in the so-called 'Harveyi clade.' The genomes of the three strains were estimated to be between 5.49Mbp and 5.95Mbp, with average G+C of 43.91%. The genome sequence data was used to estimate relatedness of the three strains to related Vibrio bacteria, including estimation of frequency of recombination events, calculation of average nucleotide identity (ANI), and a phylogenetic analysis based on concatenated alignment of nucleotide sequences of 135 protein coding genes. Results of these analyses in all cases showed the three strains forming a group clearly separate from previously described Vibrio species. A phenotypic analysis revealed that the three strains have character similar to Vibrio bacteria in the 'Harveyi clade', but can be differentiated from previously described species by testing for hydrolysis of esculin. Based on results of genomic, phylogenetic and phenotypic analyses presented in this study, it can be concluded that the three strains represent a novel species, for which the name Vibrio hyugaensis sp. nov. is proposed. The type strain is 090810a(T) (=LMG 28466(T)=NBRC 110633(T)). PMID:25952324

  7. Description of a bacteriocinogenic plasmid in Beneckea harveyi.

    PubMed Central

    McCall, J O; Sizemore, R K

    1979-01-01

    A total of 795 strains of marine Vibrio species and Beneckea harveyi, a luminescent marine bacterium, were isolated from various sources in the area of Galveston Island, Tex., and screened for the production of bacteriocin-like substances. More than 8% of the Vibrio isolates produced low-molecular-weight (dialyzable) substances, which were lethal to a test strain of V. parahaemolyticus. Approximately 5% of the B. harveyi isolates produced higher-molecular-weight (nondialyzable) substances which were lethal to a test strain of B. harveyi. One of the B. harveyi strains (strain SY) produced a nondialyzable substance which was lethal to two of 39 strains of B. harveyi. The substance showed no activity toward 17 test strains drawn from the Vibrionaceae and Enterobacteriaceae. Strain SY showed no sensitivity to its own lethal agent and was shown by agarose gel electrophoresis and electron microscopy to harbor a single plasmid of 38 x 10(6) daltons. Variants of strain SY lacking the plasmid were produced by growth in the presence of the antibiotic novobiocin. These variants lacked both the ability to produce the lethal substance and the ability to survive in its presence. The lethal agent produced by strain SY is the first bacteriocin reported in marine bacteria. The term "harveyicin" is proposed to name this lethal substance. Images PMID:317423

  8. Identification and analysis of HSP70 from Sepiella maindroni under stress of Vibrio harveyi and Cd(2.).

    PubMed

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

    2015-11-01

    The 70-kDa heat shock proteins (HSP70) play crucial roles in protecting cells against environmental stresses, such as heat shock, heavy metals and pathogenic bacteria. The full-length HSP70 cDNA of Sepiella maindroni (designated as SmHSP70, GenBank accession no. KJ739788) was 2109 bp, including an ORF of 1950 bp encoding a polypeptide of 649 amino acids with predicted pI/MW 5.24/71.30 kDa, a 62 bp-5'-UTR and a 97 bp-3'-UTR. BLASTp analysis and phylogenetic relationship strongly suggested that the amino acid sequence was a member of HSP70 family. Multiple sequence alignment revealed that SmHSP70 and other known HSP70 were highly conserved, especially in the regions of HSP70 family signatures, the bipartite nuclear targeting sequence, ATP/GTP-binding site motif and 'EEVD' motif. Time-dependent mRNA expression of SmHSP70 in the liver was recorded by quantitative real-time RT-PCR after Vibrio harveyi injection and Cd(2+) exposure. The results indicated that SmHSP70 played a significant role in mediating the environmental stress and immune response against pathogens. PMID:26192462

  9. Interaction of haematopoietic tissue cultures of the Dublin Bay Prawn, Nephrops norvegicus (L.), with the causal agent of luminous vibriosis Vibrio harveyi

    NASA Astrophysics Data System (ADS)

    Mulford, A. L.; Zhang, X. H.; Xu, H. S.; Austin, B.

    2002-04-01

    Vibrio harveyi cells (dose—<103 cells mL-1) and extracellular products (ECP; >25 μmg mL-1 of total protein concentration) destroyed haematopoietic cultures of Nephrops norvegicus within 24 h of exposure. Cytopathic effects (CPE) started after 4h of exposure to the bacterial cells, with some granularity in the cytoplasm, mostly in cells in the outer periphery of the explant growth. At the end of the infection, a considerable number of nuclei remained attached to the substrate, apparently unaffected. Following exposure to ECP, initial deterioration was observed at 2 h with the presence of granularity in the cytoplasm of<20% cells, and few cells displayed small vacuoles around the nuclei. Parallel results were obtained using whole animal experiments, with V. harveyi cells being lethal to nephrops within 24 h.

  10. Isolation of Vibrio harveyi acyl carrier protein and the fabG, acpP, and fabF genes involved in fatty acid biosynthesis.

    PubMed Central

    Shen, Z; Byers, D M

    1996-01-01

    We report the isolation of Vibrio harveyi acyl carrier protein (ACP) and cloning of a 3,973-bp region containing the fabG (encoding 3-ketoacyl-ACP reductase, 25.5 kDa), acpP (encoding ACP, 8.7 kDa), fabF (encoding 3-ketoacyl-ACP synthase II, 43.1 kDa), and pabC (encoding aminodeoxychorismate lyase, 29.9 kDa) genes. Predicted amino acid sequences were, respectively, 78, 86, 76, and 35% identical to those of the corresponding Escherichia coli proteins. Five of the 11 sequence differences between V. harveyi and E. coli ACP were nonconservative amino acid differences concentrated in a loop region between helices I and II. PMID:8550484

  11. Immune responses of barramundi, Lates calcarifer (Bloch), after administration of an experimental Vibrio harveyi bacterin by intraperitoneal injection, anal intubation and immersion.

    PubMed

    Crosbie, P B B; Nowak, B F

    2004-11-01

    Barramundi, Lates calcarifer (Bloch), were immunized with an experimental Vibrio harveyi bacterin via intraperitoneal injection, immersion and anal intubation. Both specific and non-specific immune parameters were measured to compare responses to bacterin after delivery by various methods. Elevated antibody activities in sera were found in all treatment groups with barramundi injected intraperitoneally displaying significantly higher antibody activity than the other groups. In addition, there was evidence of memory induction with a heightened antibody response in the intraperitoneally injected group only. Bacteriostatic assays indicated activity against V. harveyi in the sera of all bacterin-treated groups; again this activity was significantly higher in the intraperitoneally injected groups. There was no enhancement noted in head kidney macrophage phagocytic activity or in serum lysozyme levels. PMID:15509257

  12. Distribution of the Luminous Bacterium Beneckea harveyi in a Semitropical Estuarine Environment

    PubMed Central

    O'Brien, Catherine H.; Sizemore, Ronald K.

    1979-01-01

    Bioluminescent bacteria were found in the water column, sediment, shrimp, and gastrointestinal tract of marine fishes from the semitropical estuarine environment of the East Lagoon, Galveston Island, Tex. Populations in the water column decreased during cold weather while sedimentary populations persisted. The highest percentages of luminous organisms were isolated from the gastrointestinal tract of marine fishes, where they persisted during 5 days of starvation. The presence of chitin temporarily increased intestinal populations. All isolates were Beneckea harveyi, whose natural habitat appears to be the gut of fishes and whose free-living reservoir appears to be marine sediments. PMID:16345465

  13. Haemocyanin content of shrimp (Fenneropenaeus chinensis) associated with white spot syndrome virus and Vibrio harveyi infection process.

    PubMed

    Chang, Yanhong; Xing, Jing; Tang, Xiaoqian; Sheng, Xiuzhen; Zhan, Wenbin

    2016-01-01

    Haemocyanin (Hc) is frequently reported to vary significantly by physiological status and environmental stress in Crustaceans. In this paper, the shrimp Fenneropenaeus chinensis was infected with different concentrations of white spot syndrome virus (WSSV) and Vibrio harveyi. Then, the variation of Hc and total protein content of the haemolymph (TPCH) were investigated using the established double antibody sandwich enzyme linked immunosorbent assay (DAS-ELISA) and Coomassie brilliant blue method, respectively. The results showed that the Hc content peaked at 12h post-infection (PI) in the 10(-2), 10(-4) and 10(-6) viral supernatant (VS) groups, and the maximum was 93.032.55mgml(-1), 77.576.02mgml(-1) and 70.253.96mgml(-1), respectively. TPCH reached the maximum of 108.181.36mgml(-1) and 103.491.33mgml(-1) at 12h PI in the 10(-2) and 10(-4) VS groups, respectively. The maximum was 96.941.06mgml(-1) at 24h PI in the 10(-6) VS group. In the V.harveyi infection groups, the Hc content reached a maximum of 87.974.39mgml(-1) at 36h PI in the 10(6)CFUml(-1) group, 73.744.38mgml(-1) and 72.472.09mgml(-1) at 12h PI in the 10(7) and 10(8)CFUml(-1) groups, respectively. TPCH reached a maximum of 111.160.86mgml(-1) at 36h PI in the 10(6)CFUml(-1) group, 100.410.51mgml(-1) and 101.940.47mgml(-1) at 12h PI in the 10(7) and 10(8)CFUml(-1) groups, respectively. These data showed that both Hc content and TPCH varied as the same extent after infection. The up-regulation of the Hc content at 6-36h PI might be a reference threshold for shrimp infection. PMID:26616234

  14. Azadirachta indica (neem) leaf dietary effects on the immunity response and disease resistance of Asian seabass, Lates calcarifer challenged with Vibrio harveyi.

    PubMed

    Talpur, Allah Dad; Ikhwanuddin, Mhd

    2013-01-01

    The present study was aimed to address the possible evaluation of Azadirachta indica (neem) leaf-supplemented diets on innate immune response in Asian seabass, Lates calcarifer fingerlings against Vibrio harveyi infection. Fish were fed for two weeks diets containing six graded levels of neem leaf at 0 g, 1 g, 2 g, 3 g, 4 g and 5 g per kg feed. Fish fed neem leaf-supplemented diet displayed significant differences (p < 0.05) in weight gain, specific growth rate (SGR) and feed conversion ratio (FCR) compared to the control group fed without neem leaf-supplemented diet. Various innate immune parameters were examined pre-challenge and post-challenge. Fish was injected intraperitoneally with a lethal dose of V. harveyi containing 10(8) cells mL(-1). Supplementation of neem leaf diet significantly increased phagocytic activity, superoxide anion production, serum lysozyme, serum bactericidal activity, serum anti-protease activity throughout the experimental period when compared with the control group. Dietary doses of neem leaf diet significantly influenced the immune parameters, haematological parameters and blood biochemical indices of treated fish. The results suggested that fish fed neem leaf-supplemented diet improved the immune system and increased survival rate in L. calcarifer fingerlings against V. harveyi infection. PMID:23178500

  15. Mutation of bacterium Vibrio gazogenes for selective preparation of colorants.

    PubMed

    Alihosseini, Farzaneh; Lango, Jozsef; Ju, Kou-San; Hammock, Bruce D; Sun, Gang

    2010-01-01

    A novel marine bacterium strain effectively produced prodiginine type pigments. These colorants could dye wool, silk and synthetic fabrics such as polyester and polyacrylic and also show antibacterial properties against Escherichia coli and Staphylococcus aureus bacteria on the dyed products. Methyl nitrosoguanidine was used as a mutation agent to increase the genetic diversity and the production yield of the bacteria of the family of Vibrio gazogenes. The analysis of the mutated samples showed that two new main colorants as well as three previously found ones were produced. Liquid chromatography electro spray ionization mass spectrometry (LC-ESI-MS) and nuclear magnetic resonance (NMR) spectroscopic techniques were used to elucidate the structures of the newly produced colorants. Mass measurements revealed that the colorants C1, C2, C3, C4 have molecular masses of 321, 323, 351, and 295 Da. One unstable colorant C5 with molecular mass of 309 Da was detected as well. The mutated bacteria strains increased the yield of pigment production by about 81% and produced prodigiosin in 97% purity. The antibiotic activities of pure colorants are discussed as well. Based on their bio-activity and excellent dyeing capabilities, these colorants could be employed in cosmetic and textile industries. PMID:19902486

  16. [Cloning, physical and chemical property analysis of the Japanese sea bass Wap65-2 gene and its expression following Vibrio harveyi infection].

    PubMed

    Shi, Yu-Hong; Chen, Jiong; Gao, Shan-Shan; Shen, Guang-Qiang; Lu, Xin-Jiang; Li, Ming-Yun

    2012-10-01

    The warm temperature acclimation related 65 kDa protein-2 (Wap65-2), a teleost plasma glycoprotein, plays an important role in immune regulation against bacterial infection. Here, for the first time we determined the full length cDNA sequence of the Japanese sea bass Wap65-2 gene (1 601 bp in length excluding the 3'-polyA tail). The sequence contains an open reading frame that encodes a protein of 436 amino acids with a molecular weight of 4.8710(4). The predicted protein had a signal peptide in the N-terminal domain containing 19 residues. Sequence comparison and phylogenetic tree analysis showed that the Japanese sea bass Wap65-2 has a relatively high similarity to the Dicentrarchus labrax Wap65-2. In the healthy Japanese sea bass, Wap65-2 mRNA was expressed mainly in the liver and weakly in the heart and muscle. qRT-PCR results revealed that liver Wap65-2 transcripts were significantly increased after a Vibrio harveyi infection, and peaked 24 hour post injection (6.89 fold increase). The Japanese sea bass Wap65-2 protein was expressed in Escherichia coli and subsequently used for antiserum preparation. Western blot analysis showed that Wap65-2 was significantly increased in V. harveyi infected Japanese sea bass and reached a maximum of 5.33-fold increase at 36 h. In conclusion, the alteration of Japanese sea bass Wap65-2 expression was tightly associated with the progression of the V. harveyi bacterial infection. PMID:23019029

  17. Draft Genome Sequence of Vibrio sp. Strain Evh12, a Bacterium Retrieved from the Gorgonian Coral Eunicella verrucosa

    PubMed Central

    Franco, Telma; Califano, Gianmaria; Gonçalves, Ana C. S.; Cúcio, Catarina

    2016-01-01

    To shed light on the associations established between Vibrio species and soft corals in coastal ecosystems, we report here the draft genome sequence of Vibrio sp. strain Evh12, a bacterium that has been isolated from the gorgonian coral Eunicella verrucosa and that shows antagonistic activity against Escherichia coli. PMID:26868405

  18. Draft Genome Sequence of Vibrio sp. Strain Evh12, a Bacterium Retrieved from the Gorgonian Coral Eunicella verrucosa.

    PubMed

    Franco, Telma; Califano, Gianmaria; Gonçalves, Ana C S; Cúcio, Catarina; Costa, Rodrigo

    2016-01-01

    To shed light on the associations established between Vibrio species and soft corals in coastal ecosystems, we report here the draft genome sequence of Vibrio sp. strain Evh12, a bacterium that has been isolated from the gorgonian coral Eunicella verrucosa and that shows antagonistic activity against Escherichia coli. PMID:26868405

  19. Inhibition of Vibrio harveyi bioluminescence by cerulenin: In vivo evidence for covalent modification of the reductase enzyme involved in aldehyde synthesis

    SciTech Connect

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

    1989-07-01

    Bacterial bioluminescence is very sensitive to cerulenin, a fungal antibiotic which is known to inhibit fatty acid synthesis. When Vibrio harveyi cells pretreated with cerulenin were incubated with ({sup 3}H)myristic acid in vivo, acylation of the 57-kilodalton reductase subunit of the luminescence-specific fatty acid reductase complex was specifically inhibited. Light emission of wild-type V. harveyi was 20-fold less sensitive to cerulenin at low concentrations (10{mu}g/ml) than that of the dark mutant strain M17, which requires exogenous myristic acid for luminescence because of a defective transferase subunit. The sensitivity of myristic acid-stimulated luminescence in the mutant strain M17 exceeded that of phospholipid synthesis from ({sup 14}C)acetate, whereas uptake and incorporation of exogenous ({sup 14}C)myristic acid into phospholipids was increased by cerulenin. The reductase subunit could be labeled by incubating M17 cells with ({sup 3}H)tetrahydrocerulenin; this labeling was prevented by preincubation with either unlabeled cerulenin or myristic acid. Labeling of the reductase subunit with ({sup 3}H)tetrahydrocerulenin was also noted in an aldehyde-stimulated mutant (A16) but not in wild-type cells or in another aldehyde-stimulated mutant (M42) in which ({sup 3}H)myristoyl turnover at the reductase subunit was found to be defective. These results indicate that (i) cerulenin specifically and covalently inhibits the reductase component of aldehyde synthesis, (ii) this enzyme is partially protected from cerulenin inhibition in the wild-type strain in vivo, and (iii) two dark mutants which exhibit similar luminescence phenotypes (mutants A16 and M42) are blocked at different stages of fatty acid reduction.

  20. NH4+ transport system of a psychrophilic marine bacterium, Vibrio sp. strain ABE-1.

    PubMed

    Chou, M; Matsunaga, T; Takada, Y; Fukunaga, N

    1999-05-01

    NH4(+) transport system of a psychrophilic marine bacterium Vibrio sp. strain ABE-1 (Vibrio ABE-1) was examined by measuring the uptake of [14C]methylammonium ion (14CH3NH3+) into the intact cells. 14CH3NH3+ uptake was detected in cells grown in medium containing glutamate as the sole nitrogen source, but not in those grown in medium containing NH4Cl instead of glutamate. Vibrio ABE-1 did not utilize CH3NH3+ as a carbon or nitrogen source. NH4Cl and nonradiolabeled CH3NH3+ completely inhibited 14CH3NH3+ uptake. These results indicate that 14CH3NH3+ uptake in this bacterium is mediated via an NH4+ transport system and not by a specific carrier for CH3NH3+. The respiratory substrate succinate was required to drive 14CH3NH3+ uptake and the uptake was completely inhibited by KCN, indicating that the uptake was energy dependent. The electrochemical potentials of H+ and/or Na+ across membranes were suggested to be the driving forces for the transport system because the ionophores carbonylcyanide m-chlorophenylhydrazone and monensin strongly inhibited uptake activities at pH 6.5 and 8.5, respectively. Furthermore, KCl activated 14CH3NH3+ uptake. The 14CH3NH3+ uptake activity of Vibrio ABE-1 was markedly high at temperatures between 0 degrees and 15 degrees C, and the apparent Km value for CH3NH3+ of the uptake did not change significantly over the temperature range from 0 degrees to 25 degrees C. Thus, the NH4+ transport system of this bacterium was highly active at low temperatures. PMID:10356994

  1. 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

  2. Growth, nonspecific immune characteristics, and survival upon challenge with Vibrio harveyi in Pacific white shrimp (Litopenaeus vannamei) raised on diets containing algal meal.

    PubMed

    Nonwachai, Thasanee; Purivirojkul, Watchariya; Limsuwan, Chalor; Chuchird, Niti; Velasco, Mario; Dhar, Arun K

    2010-08-01

    A 70-day growth trial was conducted with postlarvae 12 (PL12) Pacific white shrimp (Litopenaeus vannamei) to study the suitability of soybean meal and oil originating from a single-celled microorganism (thraustochytrid) as fishmeal and fish oil substitutes in practical diets for L. vannamei. The growth, survival rate and immune characteristics were evaluated. Seven experimental diets were designed with soybean meal used as the primary protein source; each formulation contained 33% crude protein and 8% lipid. Fish oil was completely substituted with 3% soybean oil and meals originating from single-celled heterotrophs rich in docosahexaenoic acid (DHA) and arachidonic acid (ARA) were added at different concentrations. A commercial shrimp feed was used as the control diet. The final weights and survival rates of the shrimp were not significantly different among all treatments. However, shrimp raised on diets supplemented with marine algal meals rich in DHA and ARA showed significant improvement in immune parameters, such as total hemocyte count, phenoloxidase activity, superoxide dismutase activity, and bactericidal activity. Additionally, the survival rate after challenge with Vibrio harveyi was increased. These findings demonstrated that substitution of thraustochytrid-derived meals as an alternative to fish-based ingredients in shrimp diets provided similar growth rates while increasing the immune parameters and providing vibriosis resistance. PMID:20420922

  3. Citrus limonoids interfere with Vibrio harveyi cell-cell signalling and biofilm formation by modulating the response regulator LuxO.

    PubMed

    Vikram, Amit; Jesudhasan, Palmy R; Jayaprakasha, G K; Pillai, Suresh D; Patil, Bhimanagouda S

    2011-01-01

    Citrus limonoids are unique secondary metabolites, characterized by a triterpenoid skeleton with a furan ring. Studies have demonstrated beneficial health properties of limonoids. In addition, certain citrus limonoids play a role in plant defence against insect pests. In the present study, five limonoids were purified from sour orange and evaluated for their ability to inhibit cell-cell signalling. The purified limonoids were tested for their ability to interfere with cell-cell signalling and biofilm formation in Vibrio harveyi. Isolimonic acid, deacetylnomilinic acid glucoside and ichangin demonstrated significant inhibition of autoinducer-mediated cell-cell signalling and biofilm formation. Furthermore, isolimonic acid and ichangin treatment resulted in induced expression of the response regulator gene luxO. In addition, luxR promoter activity was not affected by isolimonic acid or ichangin. Therefore, the ability of isolimonic acid and ichangin to interfere with cell-cell signalling and biofilm formation seems to stem from the modulation of luxO expression. The results suggest that isolimonic acid and ichangin are potent modulators of bacterial cell-cell signalling. PMID:20864476

  4. The cycle for a Siphoviridae-like phage (VHS1) of Vibrio harveyi is dependent on the physiological state of the host.

    PubMed

    Pasharawipas, Tirasak; Wetchakit, Navin; Sriurairatana, Siriporn

    2008-08-01

    In a previous report, we isolated Vibrio harveyi (VH) 1114 together with its bacteriophage, VHS1, from a black tiger shrimp-rearing pond. The VHS1 has its lysogenic relationship to the VH1114 host as either true lysogen (TL) or pseudolysogen (PL). The characters of TL are based on the extrachromosomal existence of the VHS1 phage genome in the VH host which also simultaneously produces the VHS1 phage particles and is resistant to super-infection. The original VH1114 host exhibits a clear plaque after infection with VHS1 phage. The PL, on the other hand, exhibits a turbid plaque and does not possess the phage genome but shows toleration to the phage infection. Maintaining the PL in artificial seawater (ASW) for 1h causes the PL to be sensitive to VHS1 infection and results in clear plaques as in the original clone. A chloramphenical-added-ASW treated pseudolysogen clone (PLC), however, prevented VHS1 infection. It is postulated that the infection of VHS1 phage is regulated with a phage binding receptor which supposed to be inducible. PMID:18448184

  5. Toxicity on the luminescent bacterium Vibrio fischeri (Beijerinck). I: QSAR equation for narcotics and polar narcotics.

    PubMed

    Vighi, Marco; Migliorati, Sonia; Monti, Gianna Serafina

    2009-01-01

    Toxicity data on chemicals, supposed to have a narcotic or polar narcotic toxicological mode of action, have been produced on the luminescent bacterium Vibrio fischeri using the Microtox test procedure. Advanced statistical methods have been used to calculate statistically sound values for ecotoxicological endpoints. Simple quantitative structure activity relationship (QSAR) equations were developed for narcotics and polar narcotics. These equations were compared with those proposed by the European Technical Guidance Document on Risk Assessment for other aquatic organisms (algae, Daphnia, and fish). Similarities and differences are discussed. The need for including the bacterial component in the ecotoxicological risk assessment for aquatic ecosystems is highlighted. PMID:18582939

  6. Oxidation of fatty aldehydes to fatty acids by Escherichia coli cells expressing the Vibrio harveyi fatty aldehyde dehydrogenase (FALDH).

    PubMed

    Buchhaupt, Markus; Guder, Jan; Sporleder, Fenja; Paetzold, Melanie; Schrader, Jens

    2013-03-01

    Fatty acids represent an important renewable feedstock for the chemical industry. To enable biotechnological one carbon truncations of fatty acids, the enzymes α-dioxygenase and fatty aldehyde dehydrogenase (FALDH) have to be combined in a two-step process. We expressed an FALDH from V. harveyi in E. coli and characterized its substrate spectrum with a focus on the number and position of double bonds in the fatty aldehyde molecules. Synthesis of the expected fatty acid products was proven by analysis of whole cell biotransformation products. Coexpression of a H(2)O-forming NADPH oxidase (NOX) from Lactobacillus sanfranciscensis led to the implementation of a cofactor regeneration cycle in in vitro oxidation experiments. The presence of NOX in whole cell biotransformations improved reaction velocity but did not result in higher product yields. We could further demonstrate that at least part of the endogenous NAD(P)(+) regeneration capacity in the resting cells results from the respiratory chain. The whole cell catalyst with the high broad range FALDH activity described here is an important biotechnological module for lipid biotransformation processes, especially the shortening of fatty acids. PMID:23180547

  7. A trans-unsaturated fatty acid in a psychrophilic bacterium, Vibrio sp. strain ABE-1.

    PubMed Central

    Okuyama, H; Sasaki, S; Higashi, S; Murata, N

    1990-01-01

    A high level of a trans-unsaturated fatty acid was found in the phospholipids of a psychrophilic bacterium, Vibrio sp. strain ABE-1. This fatty acid was identified as 9-trans-hexadecenoic acid (C16:19t) by gas-liquid chromatography and infrared absorption spectrometry. C16:1(9)t accounted for less than 1% of the total fatty acids in cells grown at 5 degrees C and reached 12% of the total at 20 degrees C. We suggest that the increase in the level of the trans-unsaturated fatty acid is related to the high growth rate of this bacterium at elevated temperatures. Possible biological roles of the trans-unsaturated fatty acid in the adaptation of the microorganism to the ambient temperature are discussed. PMID:2345157

  8. Effects of mutations of the alpha His45 residue of Vibrio harveyi luciferase on the yield and reactivity of the flavin peroxide intermediate.

    PubMed

    Li, H; Ortego, B C; Maillard, K I; Willson, R C; Tu, S C

    1999-04-01

    This work was undertaken to investigate the functional consequences of mutations of the essential alpha His45 residue of Vibrio harveyi luciferase, especially with respect to the yield and reactivity of the flavin 4a-hydroperoxide intermediate II. A total of 14 luciferase variants, each with a different single-residue replacement for the alpha His45, were examined. These variants showed changes, mostly slight, in their light decay rates of the nonturnover luminescence reaction and in their Km values for decanal and reduced riboflavin 5'-phosphate (FMNH2). All alpha His45 mutants, however, showed markedly reduced bioluminescence activities, the magnitude of the reduction ranging from about 300-fold to 6 orders of magnitude. Remarkably, a good correlation was obtained for the wild-type luciferase, 12 alpha His45-mutated luciferases, and six additional variants with mutations of other alpha-subunit histidine residues between the degrees of luminescence activity reduction and the dark decay rates of intermediate II. Such a correlation further indicates that the activation of the O-O bond fission is an important function of the flavin 4a-hydroperoxide intermediate II. Both alpha H45G and alpha H45W were found to bind near-stoichiometric amounts of FMNH2. Moreover, each variant catalyzed the oxidation of bound FMNH2 by two mechanisms, with a minor pathway leading to the formation of a luminescence-active intermediate II and a major dark pathway not involving any detectable flavin 4a-hydroperoxide species. This latter pathway mimics that in the normal catalysis by flavooxidases, and its elicitation in luciferase was demonstrated for the first time by single-residue mutations. PMID:10194361

  9. A Nonluminescent and Highly Virulent Vibrio harveyi Strain Is Associated with “Bacterial White Tail Disease” of Litopenaeus vannamei Shrimp

    PubMed Central

    Zhou, Junfang; Fang, Wenhong; Yang, Xianle; Zhou, Shuai; Hu, Linlin; Li, Xincang; Qi, Xinyong; Su, Hang; Xie, Layue

    2012-01-01

    Recurrent outbreaks of a disease in pond-cultured juvenile and subadult Litopenaeus vannamei shrimp in several districts in China remain an important problem in recent years. The disease was characterized by “white tail” and generally accompanied by mass mortalities. Based on data from the microscopical analyses, PCR detection and 16S rRNA sequencing, a new Vibrio harveyi strain (designated as strain HLB0905) was identified as the etiologic pathogen. The bacterial isolation and challenge tests demonstrated that the HLB0905 strain was nonluminescent but highly virulent. It could cause mass mortality in affected shrimp during a short time period with a low dose of infection. Meanwhile, the histopathological and electron microscopical analysis both showed that the HLB0905 strain could cause severe fiber cell damages and striated muscle necrosis by accumulating in the tail muscle of L. vannamei shrimp, which led the affected shrimp to exhibit white or opaque lesions in the tail. The typical sign was closely similar to that caused by infectious myonecrosis (IMN), white tail disease (WTD) or penaeid white tail disease (PWTD). To differentiate from such diseases as with a sign of “white tail” but of non-bacterial origin, the present disease was named as “bacterial white tail disease (BWTD)”. Present study revealed that, just like IMN and WTD, BWTD could also cause mass mortalities in pond-cultured shrimp. These results suggested that some bacterial strains are changing themselves from secondary to primary pathogens by enhancing their virulence in current shrimp aquaculture system. PMID:22383954

  10. 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 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

  11. Cell-bound cations of the moderately halophilic bacterium Vibrio costicola.

    PubMed Central

    Shindler, D B; Wydro, R M; Kushner, D J

    1977-01-01

    Over most of the range of salt concentrations in which the moderately halophilic bacterium Vibrio costicola could grow, the sum of the cell-associated Na+ + K+ ions was at least as high as in the external medium. This is in contrast to other moderate halophiles, which have substantially lower internal than external salt concentrations for most of their growth range. The relative amounts of Na+ and K+ in V. costicola varied with environmental conditions. The K+/Na+ ratio fell during anaerobic incubation or when cells were poisoned. As Na+ ions left the cells, K+ ions entered. However, movement of these ions was not tightly coupled, since K+ content of cells could increase without a corresponding decrease in Na+ content. The Mg2+ contents of cells varied little with environmental conditions. PMID:263820

  12. Purification and Characterization of a New ?-Carrageenase from the Marine Bacterium Vibrio sp. NJ-2.

    PubMed

    Zhu, Benwei; Ning, Limin

    2016-02-28

    The carrageenan-degrading marine bacterium Vibrio sp. strain NJ-2 was isolated from rotten red algae, and ?-carrageenase with high activity was purified from the culture supernatant. The purified enzyme with molecular mass of 33 kDa showed the maximal activity of 937 U/mg at 40C and pH 8.0. It maintained 80% of total activity below 40C and between pH 6.0 and 10.0. The kinetics experiment showed the Km and Vmax values were 2.54 mg/ml and 138.89 mmol/min/mg, respectively. The thin layer chromatography and ESI-MS analysis of hydrolysates indicated that the enzyme can endolytically depolymerize the kappa-carrageenan into oligosaccharides with degrees of depolymerization of 2-8. Owing to its high activity, it could be a valuable tool to produce ?-carrageenan oligosaccharides with various biological activities. PMID:26528532

  13. Hepcidin-Induced Hypoferremia Is a Critical Host Defense Mechanism Against the Siderophilic Bacterium Vibrio vulnificus

    PubMed Central

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

    2014-01-01

    SUMMARY 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

  14. Vibrio oceanisediminis sp. nov., a nitrogen-fixing bacterium isolated from an artificial oil-spill marine sediment.

    PubMed

    Kang, Sang Rim; Srinivasan, Sathiyaraj; Lee, Sang-Seob

    2015-10-01

    A Gram-staining-negative, halophilic, facultatively anaerobic, motile, rod-shaped and nitrogen-fixing bacterium, designated strain S37T, was isolated from an artificial oil-spill sediment sample from the coast of Taean, South Korea. Cells grew at 10-37?C and pH?5.0-9.0, with optimal growth at 28?C and pH?6.0-8.0. Growth was observed with 1-9?% (w/v) NaCl in marine broth, with optimal growth with 3-5?% NaCl, but no growth was observed in the absence of NaCl. According to the results of 16S rRNA gene sequence analysis, strain S37T represents a member of the genus Vibrio of the class Gammaproteobacteria and forms a clade with Vibrio plantisponsor MSSRF60T (97.38?%), Vibrio diazotrophicus ATCC 33466T (97.31?%), Vibrio aestuarianus ATCC 35048T (97.07?%) Vibrio areninigrae J74T (96.76?%) and Vibrio hispanicus LMG 13240T (96.76?%). The major fatty acids were C16?:?0, C16?:?1?7c/C16?:?1?6c and C18?:?1?7c/C18?:?1?6c. The DNA G+C content was 41.9?%. The DNA-DNA hybridization analysis results showed a 30.2?% association value with the closely related type strain V. plantisponsor DSM 21026T. On the basis of phenotypic and chemotaxonomic characteristics, strain S37T represents a novel species of the genus Vibrio, for which the name Vibrio oceanisediminis sp. nov., is proposed with the type strain S37T (?=?KEMB 2255-005T?=?JCM 30409T). PMID:26296768

  15. Copper-induced production of copper-binding supernatant proteins by the marine bacterium Vibrio alginolyticus.

    PubMed Central

    Harwood-Sears, V; Gordon, A S

    1990-01-01

    Growth of the marine bacterium Vibrio alginolyticus is temporarily inhibited by micromolar levels of copper. During the copper-induced lag phase, supernatant compounds which complex and detoxify copper are produced. In this study two copper-inducible supernatant proteins having molecular masses of ca. 21 and 19 kilodaltons (CuBP1 and CuBP2) were identified; these proteins were, respectively, 25 and 46 times amplified in supernatants of copper-challenged cultures compared with controls. Experiments in which chloramphenicol was added to cultures indicated that there was de novo synthesis of these proteins in response to copper. When supernatants were separated by gel permeation chromatography, CuBP1 and CuBP2 coeluted with a copper-induced peak in copper-binding activity. CuBP1 and CuBP2 from whole supernatants were concentrated and partially purified by using a copper-charged immobilized metal ion affinity chromatography column, confirming the affinity of these proteins for copper. A comparison of cell pellets and supernatants demonstrated that CuBP1 was more concentrated in supernatants than in cells. Our data are consistent with a model for a novel mechanism of copper detoxification in which excretion of copper-binding protein is induced by copper. Images PMID:2339887

  16. Sulfonamide inhibition studies of the ?-carbonic anhydrase from the pathogenic bacterium Vibrio cholerae.

    PubMed

    Del Prete, Sonia; Vullo, Daniela; De Luca, Viviana; Carginale, Vincenzo; Ferraroni, Marta; Osman, Sameh M; AlOthman, Zeid; Supuran, Claudiu T; Capasso, Clemente

    2016-03-01

    The genome of the pathogenic bacterium Vibrio cholerae encodes for three carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the ?-, ?- and ?-classes. VchCA, the ?-CA from this species was investigated earlier, whereas the ?-class enzyme, VchCA? was recently cloned, characterized kinetically and its X-ray crystal structure reported by this group. Here we report an inhibition study with sulfonamides and one sulfamate of this enzyme. The best VchCA? inhibitors were deacetylated acetazolamide and methazolamide and hydrochlorothiazide, which showed inhibition constants of 68.2-87.0nM. Other compounds, with medium potency against VchCA?, (KIs in the range of 275-463nM), were sulfanilamide, metanilamide, sulthiame and saccharin whereas the clinically used agents such as acetazolamide, methazolamide, ethoxzolamide, dorzolamide, zonisamide and celecoxib were micromolar inhibitors (KIs in the range of 4.51-8.57?M). Identification of potent and possibly selective inhibitors of VchCA and VchCA? over the human CA isoforms, may lead to pharmacological tools useful for understanding the physiological role(s) of this under-investigated enzymes. PMID:26850377

  17. Anion inhibition studies of the ?-carbonic anhydrase from the pathogenic bacterium Vibrio cholerae.

    PubMed

    Vullo, Daniela; Del Prete, Sonia; De Luca, Viviana; Carginale, Vincenzo; Ferraroni, Marta; Dedeoglu, Nurcan; Osman, Sameh M; AlOthman, Zeid; Capasso, Clemente; Supuran, Claudiu T

    2016-03-01

    The genome of the pathogenic bacterium Vibrio cholerae encodes for three carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the ?-, ?- and ?-classes. Here we report and anion inhibition study of the ?-CA, VchCA? with anions and other small molecules which inhibit metalloenzymes. The best VchCA? anion inhibitors were sulfamide, sulfamate, phenylboronic acid and phenylarsonic acid, which showed KIs in the range of 54-86?M. Diethyldithiocarbonate was also an effective VchCA? inhibitor, with an inhibition constant of 0.73mM. The halides, cyanate, thiocyanate, cyanide, bicarbonate, carbonate, nitrate, nitrite, stannate, selenate, tellurate, divanadate, tetraborate, perrhenate, perruthenate, peroxydisulfate, selenocyanide, trithiocarbonate, and fluorosulfonate showed affinity in the low millimolar range, with KIs of 2.3-9.5mM. Identification of selective inhibitors of VchCA? (over the human CA isoforms) may lead to pharmacological tools useful for understanding the physiological role(s) of this under-investigated enzyme. PMID:26853167

  18. Interactions between the pathogenic bacterium Vibrio parahaemolyticus and red-tide dinoflagellates

    NASA Astrophysics Data System (ADS)

    Seong, Kyeong Ah; Jeong, Hae Jin

    2011-06-01

    Vibrio parahaemolyticus is a common pathogenic bacterium in marine and estuarine waters. To investigate interactions between V. parahaemolyticus and co-occurring redtide dinoflagellates, we monitored the daily abundance of 5 common red tide dinoflagellates in laboratory culture; Amphidinium carterae, Cochlodinium ploykrikoides, Gymnodinium impudicum, Prorocentrum micans, and P. minimum. Additionally, we measured the ingestion rate of each dinoflagellate on V. parahaemolyticus as a function of prey concentration. Each of the dinoflagellates responded differently to the abundance of V. parahaemolyticus. The abundances of A. carterae and P. micans were not lowered by V. parahaemolyticus, whereas that of C. polykrikodes was lowered considerably. The harmful effect depended on bacterial concentration and incubation time. Most C. polykrikoides cells died after 1 hour incubation when the V. parahaemolyticus concentration was 1.4107 cells ml-1, while cells died within 2 days of incubation when the bacterial concentration was 1.5106 cells ml-1. With increasing V. parahaemolyticus concentration, ingestion rates of P. micans, P. minimum, and A. carterae on the prey increased, whereas that on C. polykrikoides decreased. The maximum or highest ingestion rates of P. micans, P. minimum, and A. carterae on V. parahaemolyticus were 55, 5, and 2 cells alga-1 h-1, respectively. The results of the present study suggest that V. parahaemolyticus can be both the killer and prey for some red tide dinoflagellates.

  19. The Effect of Magnetic Fields on the Quorum Sensing-Regulated Luminescence of Vibrio fischeri

    NASA Astrophysics Data System (ADS)

    Barron, Addie; Hagen, Steve; Son, Minjun

    2015-03-01

    Quorum sensing (QS) is a mechanism by which bacteria communicate through the secretion and detection of extracellular signaling molecules known as autoinducers. This research focuses on the quorum sensing regulated bioluminescence of Vibrio fischeri, a marine bacterium that lives in symbiosis with certain fish and squid species. Previous studies of V. harveyi, a close relative of V. fisheri, indicate that a strong magnetic field has a positive effect on V.harveyi bioluminescence. However the effect of magnetic fields on quorum sensing-regulated luminescence is in general poorly understood. We grew V. fischeri in solid and liquid growth media, subject to strong static magnetic fields, and imaged the bioluminescence over a period of forty-eight hours. Luminescence patterns were analyzed in both the spatial and time dimensions. We find no indication that a magnetic field influences Vibrio fischeri luminescence either positively or negatively. This research was funded by the Grant Number NSF DMR-1156737.

  20. RecA Expression in Response to Solar UVR in the Marine Bacterium Vibrio natriegens.

    PubMed

    Booth, M.G.; Jeffrey, W.H.; Miller, R.V.

    2001-12-01

    Solar ultraviolet radiation may produce daily stress on marine and estuarine communities as cells are damaged and repair that damage. Reduction in the earth's stratospheric ozone layer has increased awareness of the potential effects that ultraviolet radiation may have in the environment, including how marine bacteria respond to changes in solar radiation. We examined the use of the bacterial RecA protein as an indicator of the potential of bacteria to repair DNA damage caused by solar UV irradiation using the marine bacterium Vibrio natriegens as a model. RecA is universally present in bacteria and is a regulator protein for the so-called Dark Repair Systems, which include excision repair, postreplication recombinational repair, and mutagenic or SOS repair. Solar UVB and UVA both reduced V. natriegens viability in seawater microcosms. After exposure to unfiltered solar radiation or radiation in which UVB was blocked, survival dropped below 1%, whereas visible light from which UVA and UVB had been filtered had no effect on survival. Using a RecA-specific antibody for detection, RecA protein was induced by solar radiation in a diel pattern in marine microcosms conducted in the Gulf of Mexico. Peak induction was observed at dusk each day. Although RecA expression was correlated with the formation of UVB-induced cyclobutyl pyrimidine dimers, longer wavelength UVA radiation also induced recA gene expression. Our results demonstrate that RecA-regulated, light-independent repair is an important component in the ability of marine bacteria to survive exposure to solar ultraviolet radiation and that RecA expression is a useful monitor of bacterial repair after exposure to solar UVR. PMID:12024236

  1. Dose-response behavior of the bacterium Vibrio fischeri exposed to pharmaceuticals and personal care products.

    PubMed

    de Garca, Sheyla Ortiz; Garca-Encina, Pedro A; Irusta-Mata, Rubn

    2016-01-01

    The presence of pharmaceuticals and personal care products (PPCPs) in the environment has become a real and widespread concern in recent years. Therefore, the primary goal of this study was to investigate 20 common and widely used PPCPs to assess their individual and combined effect on an important species in one trophic level, i.e., bacteria. The ecotoxicological effects of PPCPs at two different concentration ranges were determined in the bacterium Vibrio fischeri using Microtox() and were statistically analyzed using three models in the GraphPad Prism 6 program for Windows, v.6.03. A four-parameter model best fit the majority of the compounds. The half maximal effective concentration (EC50) of each PPCP was estimated using the best-fitting model and was compared with the results from a recent study. Comparative analysis indicated that most compounds showed the same level of toxicity. Moreover, the stimulatory effects of PPCPs at environmental concentrations (low doses) were assessed. These results indicated that certain compounds have traditional inverted U- or J-shaped dose-response curves, and 55% of them presented a stimulatory effect below the zero effect-concentration point. Effective concentrations of 0 (EC0), 5 (EC5) and 50% (EC50) were calculated for each PPCP as the ecotoxicological points. All compounds that presented narcosis as a mode of toxic action at high doses also exhibited stimulation at low concentrations. The maximum stimulatory effect of a mixture was higher than the highest stimulatory effect of each individually tested compound. Moreover, when the exposure time was increased, the hormetic effect decreased. Hormesis is being increasingly included in dose-response studies because this may have a harmful, beneficial or indifferent effect in an environment. Despite the results obtained in this research, further investigations need to be conducted to elucidate the behavior of PPCPs in aquatic environments. PMID:26518677

  2. Antibiofilm activity of an exopolysaccharide from marine bacterium Vibrio sp. QY101.

    PubMed

    Jiang, Peng; Li, Jingbao; Han, Feng; Duan, Gaofei; Lu, Xinzhi; Gu, Yuchao; Yu, Wengong

    2011-01-01

    Bacterial exopolysaccharides have always been suggested to play crucial roles in the bacterial initial adhesion and the development of complex architecture in the later stages of bacterial biofilm formation. However, Escherichia coli group II capsular polysaccharide was characterized to exert broad-spectrum biofilm inhibition activity. In this study, we firstly reported that a bacterial exopolysaccharide (A101) not only inhibits biofilm formation of many bacteria but also disrupts established biofilm of some strains. A101 with an average molecular weight of up to 546 KDa, was isolated and purified from the culture supernatant of the marine bacterium Vibrio sp. QY101 by ethanol precipitation, iron-exchange chromatography and gel filtration chromatography. High performance liquid chromatography traces of the hydrolyzed polysaccharides showed that A101 is primarily consisted of galacturonic acid, glucuronic acid, rhamnose and glucosamine. A101 was demonstrated to inhibit biofilm formation by a wide range of Gram-negative and Gram-positive bacteria without antibacterial activity. Furthermore, A101 displayed a significant disruption on the established biofilm produced by Pseudomonas aeruginosa, but not by Staphylococcus aureus. Importantly, A101 increased the aminoglycosides antibiotics' capability of killing P. aeruginosa biofilm. Cell primary attachment to surfaces and intercellular aggregates assays suggested that A101 inhibited cell aggregates of both P. aeruginosa and S. aureus, while the cell-surface interactions inhibition only occurred in S. aureus, and the pre-formed cell aggregates dispersion induced by A101 only occurred in P. aeruginosa. Taken together, these data identify the antibiofilm activity of A101, which may make it potential in the design of new therapeutic strategies for bacterial biofilm-associated infections and limiting biofilm formation on medical indwelling devices. The found of A101 antibiofilm activity may also promote a new recognition about the functions of bacterial exopolysaccharides. PMID:21490923

  3. Draft Genome Sequence of Environmental Bacterium Vibrio vulnificus CladeA-yb158.

    PubMed

    Danin-Poleg, Yael; Raz, Nili; Roig, Francisco J; Amaro, Carmen; Kashi, Yechezkel

    2015-01-01

    We report the genome sequence of the environmental Vibrio vulnificus biotype 1_cladeA. This draft genome of the CladeA-yb158 strain, isolated in Israel, represents this newly emerged clonal group that contains both clinical and environmental strains. PMID:26205875

  4. 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 β-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

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

    PubMed

    Goudenge, David; Boursicot, Vincent; Versigny, Typhaine; Bonnetot, Sandrine; Ratiskol, Jacqueline; Sinquin, Corinne; LaPointe, Gisle; Le Rous, Frdrique; Roux, Frdrique 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

  6. Global Analysis of Protein Lysine Succinylation Profiles and Their Overlap with Lysine Acetylation in the Marine Bacterium Vibrio parahemolyticus.

    PubMed

    Pan, Jianyi; Chen, Ran; Li, Chuchu; Li, Weiyan; Ye, Zhicang

    2015-10-01

    Protein lysine acylation, including acetylation and succinylation, has been found to be a major post-translational modification (PTM) and is associated with the regulation of cellular processes that are widespread in bacteria. Vibrio parahemolyticus is a model marine bacterium that causes seafood-borne illness in humans worldwide. The lysine acetylation of V. parahemolyticus has been extensively characterized in our previous work, and here, we report the first global analysis of lysine succinylation and the overlap between the two types of acylation in this bacterium. Using high-accuracy nano liquid chromatography-tandem mass spectrometry combined with affinity purification, we identified 1931 lysine succinylated peptides matched on 642 proteins, with the quantity of the succinyl-proteins accounting for 13.3% of the total proteins in cells. Bioinformatics analysis results showed that these succinylated proteins are involved in almost every cellular process, particularly in protein biosynthesis and metabolism, and are distributed in diverse subcellular compartments. Moreover, several sequence motifs were identified, including succinyl-lysine flanked by a lysine or arginine residue at the -8, -7, or +7 position and without these residues at the -1 or +2 position, and these motifs differ from those found in other bacteria and eukaryotic cells. Furthermore, a total of 517 succinyl-lysine sites (26.7%) on 288 proteins (44.9%) were also found to be acetylated, suggesting extensive overlap between succinylation and acetylation in this bacterium. This systematic analysis provides a promising starting point for further investigations of the physiologic and pathogenic roles of lysine succinylation and acetylation in V. parahemolyticus. PMID:26369940

  7. Construction and characterization of a fosmid library for pathogenic bacterium Vibrio anguillarum

    NASA Astrophysics Data System (ADS)

    Han, Yifan; Mo, Zhaolan; Mao, Yunxiang; Xiao, Peng; Li, Jie; Hao, Bin; Guo, Dongsheng

    2009-09-01

    Vibrio anguillarum is a common bacterial pathogen in fish. However, little is known about its pathogenic mechanism, in part, because the entire genome has not been completely sequenced. We constructed a fosmid library for V. anguillarum containing 960 clones with an average insert size of 37.7 kb and 8.6-fold genome coverage. We characterized the library by end-sequencing 50 randomly selected clones. This generated 93 sequences with a total length of 57 485 bp covering 1.4% of the whole genome. Of these sequences, 58 (62.4%) were homologous to known genes, 30 (32.3%) were genes with hypothetical functions, and the remaining 5 (5.3%) were unknown genes. We demonstrated the utility of this library by PCR screening of 10 genes. This resulted in an average of 6.2 fosmid clones per screening. This fosmid library offers a new tool for gene screening and cloning of V. anguillarum, and for comparative genomic studies among Vibrio species.

  8. 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

  9. 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

  10. Horizontal transfer of chromosomal DNA between the marine bacterium Vibrio furnissii and Escherichia coli revealed by sequence analysis.

    PubMed

    Charbit, A; Autret, N

    1998-01-01

    Previous in silico analysis of the 67.4-76.0 minutes region of the Escherichia coli genome led to the identification of a gene cluster (named aga) comprising five genes encoding homologs of the mannose transporter of E. coli, a member of the sugar-specific phosphoenolypyruvate/sugar phosphotransferase system (PTS). In the present work, we compared the aga gene cluster of E. coli, which has been considered to be involved in N-acetylgalactosamine or N-acetylmannosamine transport and metabolism, to the region comprising the recently identified mannose transporter of the marine bacterium Vibrio furnissii. Our analysis revealed that the proteins encoded by three genes (agaV, agaW, and agaA), located in the proximal portion of the aga gene cluster, shared striking similarities with the proteins encoded by the manX (IIBMan), manY (IICMan), and manD (a putative deacetylase) genes of V. furnissii, respectively (70%-82.3% identity among the three pairs of proteins). Moreover, we found that the two following aga genes (agaS and agaY) were homologous to the sequences flanking the mannose operon of V. furnissii. These observations strongly support the idea of a horizontal transfer of the chromosomally encoded man operon of V. furnissii into the E. coli genome. PMID:9697096

  11. Genomic and functional analysis of Vibrio phage SIO-2 reveals novel insights into ecology and evolution of marine siphoviruses

    PubMed Central

    Baudoux, A-C.; Hendrix, R.W.; Lander, G.C.; Bailly, X.; Podell, S.; Paillard, C.; Johnson, J.E.; Potter, C.S.; Carragher, B.; Azam, F.

    2011-01-01

    We report on a genomic and functional analysis of a novel marine siphovirus, the Vibrio phage SIO-2. This phage is lytic for related Vibrio species of great ecological interest including the broadly antagonistic bacterium Vibrio sp. SWAT3 as well as notable members of the Harveyi clade (V. harveyi ATTC BAA-1116 and V. campbellii ATCC 25920). Vibrio phage SIO-2 has a circularly permuted genome of 80,598 bp, which displays unusual features. This genome is larger than that of most known siphoviruses and only 38 of the 116 predicted proteins had homologues in databases. Another divergence is manifest by the origin of core genes, most of which share robust similarities with unrelated viruses and bacteria spanning a wide range of phyla. These core genes are arranged in the same order as in most bacteriophages but they are unusually interspaced at two places with insertions of DNA comprising a high density of uncharacterized genes. The acquisition of these DNA inserts is associated with morphological variation of SIO-2 capsid, which assembles as a large (80 nm) shell with a novel T=12 symmetry. These atypical structural features confer on SIO-2 a remarkable stability to a variety of physical, chemical and environmental factors. Given this high level of functional and genomic novelty, SIO-2 emerges as a model of considerable interest in ecological and evolutionary studies. PMID:22225728

  12. Multiple N-acyl-L-homoserine lactone autoinducers of luminescence in the marine symbiotic bacterium Vibrio fischeri.

    PubMed Central

    Kuo, A; Blough, N V; Dunlap, P V

    1994-01-01

    In Vibrio fischeri, the synthesis of N-3-oxohexanoyl-L-homoserine lactone, the autoinducer for population density-responsive induction of the luminescence operon (the lux operon, luxICDABEG), is dependent on the autoinducer synthase gene luxI. Gene replacement mutants of V. fischeri defective in luxI, which had been expected to produce no autoinducer, nonetheless exhibited lux operon transcriptional activation. Mutants released into the medium a compound that, like N-3-oxohexanoyl-L-homoserine lactone, activated expression of the lux system in a dose-dependent manner and was both extractable with ethyl acetate and labile to base. The luxI-independent compound, also like N-3-oxohexanoyl-L-homoserine lactone, was produced by V. fischeri cells in a regulated, population density-responsive manner and required the transcriptional activator LuxR for activity in the lux system. The luxI-independent compound was identified as N-octanoyl-L-homoserine lactone by coelution with the synthetic compound in reversed-phase high-pressure liquid chromatography, by derivatization treatment with 2,4-dinitrophenylhydrazine, by mass spectrometry, and by nuclear magnetic resonance spectroscopy. A locus, ain, necessary and sufficient for Escherichia coli to synthesize N-octanoyl-L-homoserine lactone was cloned from the V. fischeri genome and found to be distinct from luxI by restriction mapping and Southern hybridization. N-Octanoyl-L-homoserine lactone and ain constitute a second, novel autoinduction system for population density-responsive signalling and regulation of lux gene expression, and possibly other genes, in V. fischeri. A third V. fischeri autoinducer, N-hexanoyl-L-homoserine lactone, dependent on luxI for its synthesis, was also identified. The presence of multiple chemically and genetically distinct but cross-acting autoinduction systems in V. fischeri indicates unexpected complexity for autoinduction as a regulatory mechanism in this bacterium. Images PMID:8002580

  13. 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

    Li, Dong; Zhang, Huajun; 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

  14. 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

  15. Purification, characterization and production optimization of a vibriocin produced by mangrove associated Vibrio parahaemolyticus

    PubMed Central

    Balakrishnan, Baskar; Ranishree, Jayappriyan Kothilmozhian; Thadikamala, Sathish; Panchatcharam, Prabakaran

    2014-01-01

    Objective To identify a potential bacterium which produces antimicrobial peptide (vibriocin), and its purification, characterization and production optimization. The bacteria subjected in the study were isolated from a highly competitive ecological niche of mangrove ecosystem. Methods The bacterium was characterized by phenotype besides 16S rRNA gene sequence analysis. The antibacterial activity was recognised by using agar well diffusion method. The vibriocin was purified using ammonium sulphate precipitation, butanol extraction, gel filtration chromatography, ion-exchange chromatography and subsequently, by HPLC. Molecular weight of the substance identified in SDS-PAGE. Production optimization performed according to Taguchi's mathematical model using 6 different nutritional parameters as variables. Results The objective bacterium was identified as Vibrio parahaemolyticus. The vibriocin showed 18 KDa of molecular mass with mono peptide in nature and highest activity against pathogenic Vibrio harveyi. The peptide act stable in a wide range of pH, temperature, UV radiation, solvents and chemicals utilized. An overall ∼20% of vibriocin production was improved, and was noticed that NaCl and agitation speed played a vital role in secretion of vibriocin. Conclusion The vibriocin identified here would be an effective alternative for chemically synthesized drugs for the management of Vibrio infections in mariculture industry. PMID:25182547

  16. D-xylose isomerase from a marine bacterium, Vibrio sp. strain XY-214, and D-xylulose production from ?-1,3-xylan.

    PubMed

    Umemoto, Yoshiaki; Shibata, Toshiyuki; Araki, Toshiyoshi

    2012-02-01

    The xylA gene from a marine bacterium, Vibrio sp. strain XY-214, encoding D-xylose isomerase (XylA) was cloned and expressed in Escherichia coli. The xylA gene consisted of 1,320-bp nucleotides encoding a protein of 439 amino acids with a predicted molecular weight of 49,264. XylA was classified into group II xylose isomerases. The native XylA was estimated to be a homotetramer with a molecular mass of 190 kDa. The purified recombinant XylA exhibited maximal activity at 60C and pH 7.5. Its apparent K (m) values for D-xylose and D-glucose were 7.93 and 187 mM, respectively. Furthermore, we carried out D-xylulose production from ?-1,3-xylan, a major cell wall polysaccharide component of the killer alga Caulerpa taxifolia. The synergistic action of ?-1,3-xylanase (TxyA) and ?-1,3-xylosidase (XloA) from Vibrio sp. strain XY-214 enabled efficient saccharification of ?-1,3-xylan to D-xylose. D-xylose was then converted to D-xylulose by using XylA from the strain XY-214. The conversion rate of D-xylose to D-xylulose by XylA was found to be approximately 40% in the presence of 4 mM sodium tetraborate after 2 h of incubation. These results demonstrated that TxyA, XloA, and XylA from Vibrio sp. strain XY-214 are useful tools for D-xylulose production from ?-1,3-xylan. Because D-xylulose can be used as a source for ethanol fermentation by yeast Saccharomyces cerevisiae, the present study will provide a basis for ethanol production from ?-1,3-xylan. PMID:21519808

  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 5,652,224bp 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. 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 (SN(3J6)) 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 SN(3J6)-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

  19. Crystal structure and kinetic studies of a tetrameric type II ?-carbonic anhydrase from the pathogenic bacterium Vibrio cholerae.

    PubMed

    Ferraroni, Marta; Del Prete, Sonia; Vullo, Daniela; Capasso, Clemente; Supuran, Claudiu T

    2015-12-01

    Carbonic anhydrase (CA) is a zinc enzyme that catalyzes the reversible conversion of carbon dioxide to bicarbonate (hydrogen carbonate) and a proton. CAs have been extensively investigated owing to their involvement in numerous physiological and pathological processes. Currently, CA inhibitors are widely used as antiglaucoma, anticancer and anti-obesity drugs and for the treatment of neurological disorders. Recently, the potential use of CA inhibitors to fight infections caused by protozoa, fungi and bacteria has emerged as a new research direction. In this article, the cloning and kinetic characterization of the ?-CA from Vibrio cholerae (VchCA?) are reported. The X-ray crystal structure of this new enzyme was solved at 1.9? resolution from a crystal that was perfectly merohedrally twinned, revealing a tetrameric type II ?-CA with a closed active site in which the zinc is tetrahedrally coordinated to Cys42, Asp44, His98 and Cys101. The substrate bicarbonate was found bound in a noncatalytic binding pocket close to the zinc ion, as reported for a few other ?-CAs, such as those from Escherichia coli and Haemophilus influenzae. At pH 8.3, the enzyme showed a significant catalytic activity for the physiological reaction of the hydration of CO2 to bicarbonate and protons, with the following kinetic parameters: a kcat of 3.34 10(5)?s(-1) and a kcat/Km of 4.1 10(7)?M(-1)?s(-1). The new enzyme, on the other hand, was poorly inhibited by acetazolamide (Ki of 4.5?M). As this bacterial pathogen encodes at least three CAs, an ?-CA, a ?-CA and a ?-CA, these enzymes probably play an important role in the life cycle and pathogenicity of Vibrio, and it cannot be excluded that interference with their activity may be exploited therapeutically to obtain antibiotics with a different mechanism of action. PMID:26627652

  20. 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

  1. Purification and characterization of a novel enzyme, alpha-neoagarooligosaccharide hydrolase (alpha-NAOS hydrolase), from a marine bacterium, Vibrio sp. strain JT0107.

    PubMed Central

    Sugano, Y; Kodama, H; Terada, I; Yamazaki, Y; Noma, M

    1994-01-01

    A novel enzyme, alpha-neoagarooligosaccharide hydrolase (EC 3.2.1.-), which hydrolyzes the alpha-1,3 linkage of neoagarooligosaccharides to yield agaropentaose (O-beta-D-galactopyranosyl(1-->4)-O-3,6-anhydro-alpha-L-galactopyranosyl (1-->3)-D-galactose], agarotriose [O-beta-D-galactopyranosyl(1-->4)-O-3,6-anhydro- alpha-L-galactopyranosyl (1-->3)-D-galactose], agarobiose [O-beta-D-galactopyranosyl(1-->4)-3,6-anhydro-L-galactose], 3,6-anhydro-L-galactose, and D-galactose was isolated from the marine bacterium Vibrio sp. strain JT0107 and characterized. This enzyme was purified 383-fold from cultured cells by using a combination of ammonium sulfate precipitation, successive anion-exchange column chromatography, gel filtration, and hydroxyapatite chromatography, gel filtration, and hydroxyapatite chromatography. The purified protein gave a single band (M(r), 42,000) on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Estimation of the M(r) by the gel filtration method gave a value of 84,000, indicating that the enzyme is dimeric. Amino acid sequence analysis revealed it to have a single N-terminal sequence that has no sequence homology to any other known agarases. The optimum temperature and pH were 30 degrees C and 7.7, respectively. The Km and maximum rate of metabolism for neoagarobiose were 5.37 mM and 92 U/mg of protein, respectively. Images PMID:7961439

  2. Extracellular nuclease produced by a marine bacterium. II. Purification and properties of extracellular nuclease from a marine Vibrio sp.

    PubMed

    Maeda, M; Taga, N

    1976-10-01

    Extracellular nuclease produced by a marine Vibrio sp., strain No. 2, was purified by salting out with ammonium sulfate and by chromatography on a DEAE-cellulose column and twice on a Sephadex G-200 column. The nuclease was eluted as a single peak in which the deoxyribonuclease (DNase) activity and ribonuclease (RNase) activity appeared together. Polyacrylamide disc gel electrophoresis showed a single band of stained protein which had both DNase and RNase activity. The molecular weight of the enzyme was estimated to be 100 000 daltons. When using partially purified enzyme from the DEAE-cellulose column, the optimum pH for activity was 8.0, and the enzyme was activated strongly by 0.05 M Mg2+ ions and stabilized by 0.01 M Ca2+ ion. These concentrations of Mg2+ and Ca2+ ions are similar to those of the two cations in seawater. Indeed, the enzyme revealed high activity and strong stability when kept in seawater. The presence of particulate matter, such as cellulose powder, chitin powder. Hyflosupercel, Kaolin, and marine mud increased the stability of the enzyme. When the hydrostatic pressure was increased from 1 to 1000 atmospheres, the decrements of the enzyme activity were more pronounced at 30 and 40 degrees C than at 25 or 50 degrees C. The enzyme activity was restored after decompression to 1 atm at 30 degrees C. PMID:10061

  3. Draft Genome Sequence of Non-Vibrio parahaemolyticus Acute Hepatopancreatic Necrosis Disease Strain KC13.17.5, Isolated from Diseased Shrimp in Vietnam

    PubMed Central

    Kondo, Hidehiro; Van, Phan Thi; Dang, Lua T.

    2015-01-01

    A strain of Vibrio (KC13.17.5) causing acute hepatopancreatic necrosis disease (AHPND) in shrimp in northern Vietnam was isolated. Normally, AHPND is caused by Vibrioparahaemolyticus, but the genomic sequence of the strain indicated that it belonged to Vibrioharveyi. The sequence data included plasmid-like sequences and putative virulence genes. PMID:26383659

  4. Draft Genome Sequence of Non-Vibrio parahaemolyticus Acute Hepatopancreatic Necrosis Disease Strain KC13.17.5, Isolated from Diseased Shrimp in Vietnam.

    PubMed

    Kondo, Hidehiro; Van, Phan Thi; Dang, Lua T; Hirono, Ikuo

    2015-01-01

    A strain of Vibrio (KC13.17.5) causing acute hepatopancreatic necrosis disease (AHPND) in shrimp in northern Vietnam was isolated. Normally, AHPND is caused by Vibrioparahaemolyticus, but the genomic sequence of the strain indicated that it belonged to Vibrioharveyi. The sequence data included plasmid-like sequences and putative virulence genes. PMID:26383659

  5. Comparison of the sulfonamide inhibition profiles of the α-, β- and γ-carbonic anhydrases from the pathogenic bacterium Vibrio cholerae.

    PubMed

    Del Prete, Sonia; Vullo, Daniela; De Luca, Viviana; Carginale, Vincenzo; Osman, Sameh M; AlOthman, Zeid; Supuran, Claudiu T; Capasso, Clemente

    2016-04-15

    Carbonic anhydrases (CA, EC 4.2.1.1) are ubiquitous metalloenzymes, which catalyze the conversion of carbon dioxide (CO2) to bicarbonate (HCO3(-)) and protons (H(+)). In prokaryotes, the existence of genes encoding for α-, β- and γ-classes suggests that these enzymes play an important role in the prokaryotic physiology. It has been demonstrated, in fact, that their inhibition in vivo leads to growth impairment or growth defects of the microorganism. Ultimately, we started to investigate the biochemical properties and the inhibitory profiles of the α- and β-CAs identified in the genome of Vibrio cholerae, which is the causative agent of cholera. The genome of this pathogen encodes for CAs belonging to α, β and γ classes. Here, we report a sulfonamide inhibition study of the γ-CA (named VchCAγ) comparing it with data obtained for the α- and β-CA enzymes. VchCAγ activity (kcat=7.39×10(5)s(-1)) was significantly higher than the other γ-CAs. The inhibition study with a panel of sulfonamides and one sulfamate led to the detection of a large number of nanomolar VchCAγ inhibitors, including simple aromatic/heterocyclic sulfonamides (compounds 2-9, 11, 13-15, 24) as well as EZA, DZA, BRZ, BZA, TPM, ZNS, SLP, IND (KIs in the range of 66.2-95.3nM). As it was proven that bicarbonate is a virulence factor of this bacterium and since ethoxzolamide was shown to inhibit this virulence in vivo, we propose that VchCA, VchCAβ and VchCAγ may be a target for antibiotic development, exploiting a mechanism of action rarely considered up until now, i.e., interference with bicarbonate supply as a virulence factor. PMID:26972117

  6. Molecular cloning and characterization of a novel ?-1,3-xylanase possessing two putative carbohydrate-binding modules from a marine bacterium Vibrio sp. strain AX-4

    PubMed Central

    2005-01-01

    We cloned a novel ?-1,3-xylanase gene, consisting of a 1728-bp open reading frame encoding 576 amino acid residues, from a marine bacterium, Vibrio sp. strain AX-4. Sequence analysis revealed that the ?-1,3-xylanase is a modular enzyme composed of a putative catalytic module belonging to glycoside hydrolase family 26 and two putative carbohydrate-binding modules belonging to family 31. The recombinant enzyme hydrolysed ?-1,3-xylan to yield xylo-oligosaccharides with different numbers of xylose units, mainly xylobiose, xylotriose and xylotetraose. However, the enzyme did not hydrolyse ?-1,4-xylan, ?-1,4-mannan, ?-1,4-glucan, ?-1,3-xylobiose or p-nitrophenyl-?-xyloside. When ?-1,3-xylo-oligosaccharides were used as the substrate, the kcat value of the enzyme for xylopentaose was found to be 40times higher than that for xylotetraose, and xylotriose was extremely resistant to hydrolysis by the enzyme. A PSI-BLAST search revealed two possible catalytic Glu residues (Glu-138 as an acid/base catalyst and Glu-234 as a nucleophile), both of which are generally conserved in glycoside hydrolase superfamily A. Replacement of these two conserved Glu residues with Asp and Gln resulted in a significant decrease and complete loss of enzyme activity respectively, without a change in their CD spectra, suggesting that these Glu residues are the catalytic residues of ?-1,3-xylanase. The present study also clearly shows that the non-catalytic putative carbohydrate-binding modules play an important role in the hydrolysis of insoluble ?-1,3-xylan, but not that of soluble glycol-?-1,3-xylan. Furthermore, repeating a putative carbohydrate-binding module strongly enhanced the hydrolysis of the insoluble substrate. PMID:15743273

  7. Multiple Regulators Control Capsular Polysaccharide Production in Vibrio parahaemolyticus

    PubMed Central

    Gvener, Zehra Tzn; McCarter, Linda L.

    2003-01-01

    Vibrio parahaemolyticus, a biofouling marine bacterium and human pathogen, undergoes phase variation displaying translucent (TR) and opaque (OP) colony morphologies. Prior studies demonstrated that OP colonies produce more capsular polysaccharide (CPS) than TR colonies and that opacity is controlled by the Vibrio harveyi LuxR-type transcriptional activator OpaR. CPS has also been shown to be regulated by the scrABC signaling pathway, which involves a GGDEF-EAL motif-containing sensory protein. The present study identifies cps genes and examines their regulation. Transposon insertions in the cps locus, which contains 11 genes, abolished opacity. Such mutants failed to produce CPS and were defective in pellicle formation in microtiter wells and in a biofilm attachment assay. Reporter fusions to cpsA, the first gene in the locus, showed ?10-fold-enhanced transcription in the OP (opaR+) strain compared to a TR (?opaR) strain. Two additional transcriptional regulators were discovered. One potential activator, CpsR, participates in the scrABC GGDEF-EAL-signaling pathway; CpsR was required for the increased cps expression observed in scrA ?opaR strains. CpsR, which contains a conserved module found in members of the AAA+ superfamily of ATP-interacting proteins, is homologous to Vibrio cholerae VpsR; however, unlike VpsR, CpsR was not essential for cps expression. CpsS, the second newly identified regulator, contains a CsgD-type DNA-binding domain and appears to act as a repressor. Mutants with cpsS defects have greatly elevated cps transcription; their high level of cpsA expression was CpsR dependent in ?R strains and primarily OpaR dependent in OP strains. Thus, a network of positive and negative regulators modulates CPS production in V. parahaemolyticus. PMID:12949095

  8. Complete genome sequence of a giant Vibrio bacteriophage VH7D.

    PubMed

    Luo, Zhu-Hua; Yu, Yan-Ping; Jost, Günter; Xu, Wei; Huang, Xiang-Ling

    2015-12-01

    A Vibrio sp. lytic phage VH7D was isolated from seawater of an abalone farm in Xiamen, China. The phage was capable of lysing Vibrio rotiferianus DSM 17186(T) and Vibrio harveyi DSM 19623(T). The complete genome of this phage consists of 246,964 nucleotides with a GC content of 41.31%, which characterized it as a giant vibriophage. Here we report the complete genome sequence and major findings from the genomic annotation. PMID:26476690

  9. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... cholera caused by the bacterium Vibrio cholerae and provides epidemiological information on cholera. Cholera is an acute infectious disease characterized by severe diarrhea with extreme fluid and...

  10. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... cholera caused by the bacterium Vibrio cholerae and provides epidemiological information on cholera. Cholera is an acute infectious disease characterized by severe diarrhea with extreme fluid and...

  11. Plasmid- and chromosome-encoded siderophore anguibactin systems found in marine vibrios: biosynthesis, transport and evolution.

    PubMed

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

    2013-08-01

    Vibrio anguillarum is a marine pathogen that causes vibriosis, a hemorrhagic septicemia in aquatic invertebrate as well as vertebrate animals. The siderophore anguibactin system is one of the most important virulence factors of this bacterium. Most of the anguibactin biosynthesis and transport genes are located in the 65-kb pJM1 virulence plasmid although some of them are found in the chromosome of this fish pathogen. Over 30years of research unveiled the role numerous chromosomal and pJM1 genes play in the synthesis of anguibactin and the transport of cognate ferric complexes into the bacterial cell. Furthermore, these studies showed that pJM1-carrying strains might be originated from pJM1-less strains producing the chromosome-mediated siderophore vanchrobactin. Additionally, we recently identified a chromosome-mediated anguibactin system in V. harveyi suggesting the possible evolutional origin of the V. anguillarum anguibactin system. In this review, we present our current understanding of the mechanisms and evolution hypothesis of the anguibactin system that might have occurred in these pathogenic vibrios. PMID:23660776

  12. Novel host-specific iron acquisition system in the zoonotic pathogen Vibrio vulnificus.

    PubMed

    Pajuelo, David; Lee, Chung-Te; Roig, Francisco J; Hor, Lien-I; Amaro, Carmen

    2015-06-01

    Vibrio vulnificus is a marine bacterium associated with human and fish (mainly farmed eels) diseases globally known as vibriosis. The ability to infect and overcome eel innate immunity relies on a virulence plasmid (pVvbt2) specific for biotype 2 (Bt2) strains. In the present study, we demonstrated that pVvbt2 encodes a host-specific iron acquisition system that depends on an outer membrane receptor for eel transferrin called Vep20. The inactivation of vep20 did not affect either bacterial growth in human plasma or virulence for mice, while bacterial growth in eel blood/plasma was abolished and virulence for eels was significantly impaired. Furthermore, vep20 is an iron-regulated gene overexpressed in eel blood during artificially induced vibriosis both in vitro and in vivo. Interestingly, homologues to vep20 were identified in the transferable plasmids of two fish pathogen species of broad-host range, Vibrio harveyi (pVh1) and Photobacterium damselae subsp. damselae (pPHDD1). These data suggest that Vep20 belongs to a new family of plasmid-encoded fish-specific transferrin receptors, and the acquisition of these plasmids through horizontal gene transfer is likely positively selected in the fish-farming environment. Moreover, we propose Ftbp (fish transferrin binding proteins) as a formal name for this family of proteins. PMID:25630302

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

    PubMed Central

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

    2009-01-01

    Certain bacteria use cell-to-cell chemical communication to coordinate community-wide phenotypic expression, 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 in cocultivation experiments. With the use of bioassay-guided fractionation, two phenethylamide metabolites were identified as the active agents. The compounds additionally inhibit quorum sensing-regulated violacein biosynthesis by Chromobacterium violaceum CV026 and green fluorescent protein production by Escherichia coli JB525. Bacterial growth was unaffected at concentrations below 200 ?g/ml. Evidence is presented that these nontoxic metabolites may act as antagonists of bacterial quorum sensing by competing with N-acyl homoserine lactones for receptor binding. PMID:19060172

  14. Luciferase-dependent oxygen consumption by bioluminescent vibrios

    SciTech Connect

    Makemson, J.C.

    1986-02-01

    Oxygen uptake due to luciferase in two luminous Vibrio species was estimated in vivo by utilizing inhibitors having specificities for luciferase (decanol) and cytochromes (cyanide). Cyanide titration of respiration revealed a component of oxygen uptake less sensitive to cyanide which was completely inhibitable by low concentrations of decanol. From this it was estimated that in vivo luciferase is responsible for less than 12% (Vibrio harveyi) or 20% (Vibrio fischeri) of the total respiration. From these data in vivo bioluminescent quantum yields are estimated to be not lower than 1.7 and 2.6%, respectively.

  15. 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

  16. Advanced Microbial Taxonomy Combined with Genome-Based-Approaches Reveals that Vibrio astriarenae sp. nov., an Agarolytic Marine Bacterium, Forms a New Clade in Vibrionaceae

    PubMed Central

    Al-saari, Nurhidayu; Gao, Feng; A.K.M. Rohul, Amin; Sato, Kazumichi; Sato, Keisuke; Mino, Sayaka; Suda, Wataru; Oshima, Kenshiro; Hattori, Masahira; Ohkuma, Moriya; Meirelles, Pedro M.; Thompson, Fabiano L.; Thompson, Cristiane; A. Filho, Gilberto M.; Gomez-Gil, Bruno; Sawabe, Toko; Sawabe, Tomoo

    2015-01-01

    Advances in genomic microbial taxonomy have opened the way to create a more universal and transparent concept of species but is still in a transitional stage towards becoming a defining robust criteria for describing new microbial species with minimum features obtained using both genome and classical polyphasic taxonomies. Here we performed advanced microbial taxonomies combined with both genome-based and classical approaches for new agarolytic vibrio isolates to describe not only a novel Vibrio species but also a member of a new Vibrio clade. Two novel vibrio strains (Vibrio astriarenae sp. nov. C7T and C20) showing agarolytic, halophilic and fermentative metabolic activity were isolated from a seawater sample collected in a coral reef in Okinawa. Intraspecific similarities of the isolates were identical in both sequences on the 16S rRNA and pyrH genes, but the closest relatives on the molecular phylogenetic trees on the basis of 16S rRNA and pyrH gene sequences were V. hangzhouensis JCM 15146T (97.8% similarity) and V. agarivorans CECT 5085T (97.3% similarity), respectively. Further multilocus sequence analysis (MLSA) on the basis of 8 protein coding genes (ftsZ, gapA, gyrB, mreB, pyrH, recA, rpoA, and topA) obtained by the genome sequences clearly showed the V. astriarenae strain C7T and C20 formed a distinct new clade protruded next to V. agarivorans CECT 5085T. The singleton V. agarivorans has never been included in previous MLSA of Vibrionaceae due to the lack of some gene sequences. Now the gene sequences are completed and analysis of 100 taxa in total provided a clear picture describing the association of V. agarivorans into pre-existing concatenated network tree and concluded its relationship to our vibrio strains. Experimental DNA-DNA hybridization (DDH) data showed that the strains C7T and C20 were conspecific but were separated from all of the other Vibrio species related on the basis of both 16S rRNA and pyrH gene phylogenies (e.g., V. agarivorans CECT 5085T, V. hangzhouensis JCM 15146T V. maritimus LMG 25439T, and V. variabilis LMG 25438T). In silico DDH data also supported the genomic relationship. The strains C7T also had less than 95% average amino acid identity (AAI) and average nucleotide identity (ANI) towards V. maritimus C210, V. variabilis C206, and V. mediterranei AK1T, V. brasiliensis LMG 20546T, V. orientalis ATCC 33934T, and V. sinaloensis DSM 21326. The name Vibrio astriarenae sp. nov. is proposed with C7 as the type strains. Both V. agarivorans CECT 5058T and V. astriarenae C7T are members of the newest clade of Vibrionaceae named Agarivorans. PMID:26313925

  17. Inhibition of Vibrio biofilm formation by a marine actinomycete strain A66.

    PubMed

    You, JianLan; Xue, XiaoLi; Cao, LiXiang; Lu, Xin; Wang, Jian; Zhang, LiXin; Zhou, ShiNing

    2007-10-01

    China remains by far the largest aquaculture producer in the world. However, biofilms formed by pathogenic Vibrio strains pose serious problems to marine aquaculture. To provide a strategy for biofilm prevention, control, and eradication, extracts from 88 marine actinomycetes were screened. Thirty-five inhibited the biofilm formation of Vibrio harveyi, Vibrio vulnificus, and Vibrio anguillarum at a concentration of 2.5% (v/v). Thirty-three of the actinomycete extracts dispersed the mature biofilm. Six extracts inhibited the quorum-sensing system of V. harveyi by attenuating the signal molecules N-acylated homoserine lactones' activity. Strain A66, which was identified as Streptomyces albus, both attenuated the biofilms and inhibited their quorum-sensing system. It is suggested that strain A66 is a promising candidate to be used in future marine aquaculture. PMID:17624525

  18. Cloning of a Novel Gene Encoding β-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 β-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 β-1,3-xylosidase hydrolyzed β-1,3-xylooligosaccharides to d-xylose as a final product. PMID:17993567

  19. Cloning, Sequencing, and Expression in Escherichia coli of the New Gene Encoding β-1,3-Xylanase from a Marine Bacterium, Vibrio sp. Strain XY-214

    PubMed Central

    Araki, Toshiyoshi; Hashikawa, Shinnosuke; Morishita, Tatsuo

    2000-01-01

    The Vibrio sp. strain XY-214 β-1,3-xylanase gene cloned in Escherichia coli DH5α consisted of an open reading frame of 1,383 nucleotides encoding a protein of 460 amino acids with a molecular mass of 51,323 Da and had a signal peptide of 22 amino acids. The transformant enzyme hydrolyzed β-1,3-xylan to produce several xylooligosaccharides. PMID:10742274

  20. 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...

  1. 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

  2. Occurrence and Diversity of Clinically Important Vibrio Species in the Aquatic Environment of Georgia.

    PubMed

    Kokashvili, Tamar; Whitehouse, Chris A; Tskhvediani, Ana; Grim, Christopher J; Elbakidze, Tinatin; Mitaishvili, Nino; Janelidze, Nino; Jaiani, Ekaterine; Haley, Bradd J; Lashkhi, Nino; Huq, Anwar; Colwell, Rita R; Tediashvili, Marina

    2015-01-01

    Among the more than 70 different Vibrio species inhabiting marine, estuarine, and freshwater ecosystems, 12 are recognized as human pathogens. The warm subtropical climate of the Black Sea coastal area and inland regions of Georgia likely provides a favorable environment for various Vibrio species. From 2006 to 2009, the abundance, ecology, and diversity of clinically important Vibrio species were studied in different locations in Georgia and across seasons. Over a 33-month period, 1,595 presumptive Vibrio isolates were collected from the Black Sea (n?=?657) and freshwater lakes around Tbilisi (n?=?938). Screening of a subset of 440 concentrated and enriched water samples by PCR-electrospray ionization/mass spectrometry (PCR-ESI/MS) detected the presence of DNA from eight clinically important Vibrio species: V. cholerae, V. parahaemolyticus, V. vulnificus, V. mimicus, V. alginolyticus, V. harveyi, V. metschnikovii, and V. cincinnatiensis. Almost 90% of PCR/ESI-MS samples positive for Vibrio species were collected from June through November. Three important human-pathogenic Vibrio species (V. cholerae, V. parahaemolyticus, and V. vulnificus) were detected in 62.8, 37.8, and 21.4% of samples testing positive for Vibrios, respectively. The results of these activities suggest that natural reservoirs for human-pathogenic Vibrios exist in Georgian aquatic environments. Water temperature at all sampling sites was positively correlated with the abundance of clinically important Vibrio spp. (except V. metschnikovii), and salinity was correlated with species composition at particular Black Sea sites as well as inland reservoirs. PMID:26528464

  3. Deep-sea hydrothermal vent bacteria related to human pathogenic Vibrio species.

    PubMed

    Hasan, Nur A; Grim, Christopher J; Lipp, Erin K; Rivera, Irma N G; Chun, Jongsik; Haley, Bradd J; Taviani, Elisa; Choi, Seon Young; Hoq, Mozammel; Munk, A Christine; Brettin, Thomas S; Bruce, David; Challacombe, Jean F; Detter, J Chris; Han, Cliff S; Eisen, Jonathan A; Huq, Anwar; Colwell, Rita R

    2015-05-26

    Vibrio species are both ubiquitous and abundant in marine coastal waters, estuaries, ocean sediment, and aquaculture settings worldwide. We report here the isolation, characterization, and genome sequence of a novel Vibrio species, Vibrio antiquarius, isolated from a mesophilic bacterial community associated with hydrothermal vents located along the East Pacific Rise, near the southwest coast of Mexico. Genomic and phenotypic analysis revealed V. antiquarius is closely related to pathogenic Vibrio species, namely Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio harveyi, and Vibrio vulnificus, but sufficiently divergent to warrant a separate species status. The V. antiquarius genome encodes genes and operons with ecological functions relevant to the environment conditions of the deep sea and also harbors factors known to be involved in human disease caused by freshwater, coastal, and brackish water vibrios. The presence of virulence factors in this deep-sea Vibrio species suggests a far more fundamental role of these factors for their bacterial host. Comparative genomics revealed a variety of genomic events that may have provided an important driving force in V. antiquarius evolution, facilitating response to environmental conditions of the deep sea. PMID:25964331

  4. Occurrence and Diversity of Clinically Important Vibrio Species in the Aquatic Environment of Georgia

    PubMed Central

    Kokashvili, Tamar; Whitehouse, Chris A.; Tskhvediani, Ana; Grim, Christopher J.; Elbakidze, Tinatin; Mitaishvili, Nino; Janelidze, Nino; Jaiani, Ekaterine; Haley, Bradd J.; Lashkhi, Nino; Huq, Anwar; Colwell, Rita R.; Tediashvili, Marina

    2015-01-01

    Among the more than 70 different Vibrio species inhabiting marine, estuarine, and freshwater ecosystems, 12 are recognized as human pathogens. The warm subtropical climate of the Black Sea coastal area and inland regions of Georgia likely provides a favorable environment for various Vibrio species. From 2006 to 2009, the abundance, ecology, and diversity of clinically important Vibrio species were studied in different locations in Georgia and across seasons. Over a 33-month period, 1,595 presumptive Vibrio isolates were collected from the Black Sea (n?=?657) and freshwater lakes around Tbilisi (n?=?938). Screening of a subset of 440 concentrated and enriched water samples by PCR-electrospray ionization/mass spectrometry (PCR-ESI/MS) detected the presence of DNA from eight clinically important Vibrio species: V. cholerae, V. parahaemolyticus, V. vulnificus, V. mimicus, V. alginolyticus, V. harveyi, V. metschnikovii, and V. cincinnatiensis. Almost 90% of PCR/ESI-MS samples positive for Vibrio species were collected from June through November. Three important human-pathogenic Vibrio species (V. cholerae, V. parahaemolyticus, and V. vulnificus) were detected in 62.8, 37.8, and 21.4% of samples testing positive for Vibrios, respectively. The results of these activities suggest that natural reservoirs for human-pathogenic Vibrios exist in Georgian aquatic environments. Water temperature at all sampling sites was positively correlated with the abundance of clinically important Vibrio spp. (except V. metschnikovii), and salinity was correlated with species composition at particular Black Sea sites as well as inland reservoirs. PMID:26528464

  5. Deep-sea hydrothermal vent bacteria related to human pathogenic Vibrio species

    PubMed Central

    Hasan, Nur A.; Grim, Christopher J.; Lipp, Erin K.; Rivera, Irma N. G.; Chun, Jongsik; Haley, Bradd J.; Taviani, Elisa; Choi, Seon Young; Hoq, Mozammel; Munk, A. Christine; Brettin, Thomas S.; Bruce, David; Challacombe, Jean F.; Detter, J. Chris; Han, Cliff S.; Eisen, Jonathan A.; Huq, Anwar; Colwell, Rita R.

    2015-01-01

    Vibrio species are both ubiquitous and abundant in marine coastal waters, estuaries, ocean sediment, and aquaculture settings worldwide. We report here the isolation, characterization, and genome sequence of a novel Vibrio species, Vibrio antiquarius, isolated from a mesophilic bacterial community associated with hydrothermal vents located along the East Pacific Rise, near the southwest coast of Mexico. Genomic and phenotypic analysis revealed V. antiquarius is closely related to pathogenic Vibrio species, namely Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio harveyi, and Vibrio vulnificus, but sufficiently divergent to warrant a separate species status. The V. antiquarius genome encodes genes and operons with ecological functions relevant to the environment conditions of the deep sea and also harbors factors known to be involved in human disease caused by freshwater, coastal, and brackish water vibrios. The presence of virulence factors in this deep-sea Vibrio species suggests a far more fundamental role of these factors for their bacterial host. Comparative genomics revealed a variety of genomic events that may have provided an important driving force in V. antiquarius evolution, facilitating response to environmental conditions of the deep sea. PMID:25964331

  6. Vibrio parahaemolyticus

    MedlinePLUS

    ... commonly found in warm marine and estuarine environments. Incidence Nationwide, an average of 215 culture-confirmed cases, ... Team CDC Features : includes information about Vibrio illness Incidence and Trends in Foodborne Illness, 2012 Incidence and ...

  7. Improvement of innate immune responses and defense activity in tiger shrimp (Penaeus monodon Fab.) by intramuscular administration of the outer membrane protein Vibrio alginolyticus.

    PubMed

    Maftuch; Prasetio, E; Sudianto, A; Rozik, M; Nurdiyani, R; Sanusi, E; Nursyam, H; Fariedah, F; Marsoedi; Murachman

    2013-01-01

    The Outer Membrane Protein (OMP) of Vibrio alginolyticus cell wall was administered intramuscularly (IM) to the tiger shrimp (Penaeus monodon Fab.) at 10, 20, 30?g/kg bw. After 14days infection, the tiger shrimps were challenged with 10(7) bacterial density of Vibrio harveyi for 24hours. The total haemocyte count (THC), differential haemocyte count (DHC) and amount of total protein plasma (TPP), superoxide dismutase and protease enzyme activity were monitored. The results showed that intramuscular administration of OMP enhanced an immunomodulatory effect and protection against V. harveyi. The beneficial effect of OMP on the tiger shrimp is dose-dependent and OMP-20?g/kg bw is an optimal dose after two times of boosters for 14days against V. harveyi infection. PMID:24058892

  8. Identification of DLD, by immunoproteomic analysis and evaluation as a potential vaccine antigen against three Vibrio species in Epinephelus coioides.

    PubMed

    Pang, Huanying; Chen, Liming; Hoare, Rowena; Huang, Yucong; ZaoheWu; Jian, Jichang

    2016-02-24

    Vibrio spp. represent a serious threat to the culture of Epinephelus coioides (Orange-spotted Grouper) in Southeast Asia. In this study we used two-dimensional electrophoresis (2-DE) and Western blotting to identify common immunogenic proteins of Vibrio alginolyticus, Vibrio harveyi and Vibrio parahaemolyticus. Membranes were probed with orange-spotted grouper anti-V. alginolyticus sera and accordingly 60, 58 and 48 immunogenic protein spots were detected. By matching analysis for the three Western blotting membranes, 6 cross immunogenic spots for the three Vibrio species were identified. They were Outer membrane protein W (OmpW), dihydrolipoamide dehydrogenase (DLD), succinate dehydrogenase flavoprotein subunit(SDHA), elongation factor Ts(Ts), peptide ABC transporter periplasmic peptide-binding protein and phosphoenolpyruvate carboxykinase(PEPCK). One of the proteins, DLD, was used to evaluate the cross protective function for E. coioides with a bacterial immunization and challenge method. The relative percent survival rate of E. coioides against V. alginolyticus, V. harveyi and V. parahaemolyticus was 90%, 86% and 80%, respectively. This work may provide potential cross protective vaccine candidate antigens for three Vibrio species, and DLD may be considered as an effective cross-protective immunogen against three Vibrio species. PMID:26562319

  9. Rapid identification and differentiation of Vibrio parahaemolyticus from Vibrio spp. in seafood samples using developed monoclonal antibodies.

    PubMed

    Prompamorn, Piyanuch; Longyant, Siwaporn; Pengsuk, Chalinan; Sithigorngul, Paisarn; Chaivisuthangkura, Parin

    2013-04-01

    Monoclonal antibodies (MAbs) specific to Vibrio parahaemolyticus were successfully generated. According to the specificity of V. parahaemolyticus, MAbs can be classified into 5 groups. The MAbs VP-2D and VP-11H were specific to the O2 and O4 groups of V. parahaemolyticus, respectively. The MAb VP-11B reacted with 11 out of 30 isolates of V. parahaemolyticus used in this study. The MAb VP-516 bound to 27 out of 30 isolates of V. parahaemolyticus and cross reacted with all 10 isolates of V. alginolyticus. The MAb VP-618 demonstrated positive reactivity to 29 out of 30 isolates of V. parahaemolyticus and demonstrated slight cross reactivity to 3 out of 30 isolates of V. harveyi. The sensitivity of the MAbs ranged from 10(8) to 10(7) c.f.u. ml(-1) for V. parahaemolyticus obtained from pure cultures and depended on the group of MAbs. However, the detection capability could be improved to be equivalent to that of the PCR technique following pre-incubation of the samples in alkaline peptone water (APW). Using these MAbs along with MAbs specific to V. alginolyticus (VA-165), V. cholerae (VC-63), V. harveyi (VH-9B and VH-20C) and Vibrio spp. (VC-201) from previous studies, V. parahaemolyticus could be identified and differentiated from Vibrio spp. in various seafood samples including shrimp, green mussels, blood clams and oysters by a simple dot blot immunoassay without the requirement for bacterial isolation or biochemical characterization. PMID:23233121

  10. Virulence genes and pathogenicity islands in environmental Vibrio strains nonpathogenic to humans.

    PubMed

    Gennari, Micol; Ghidini, Valentina; Caburlotto, Greta; Lleo, Maria M

    2012-12-01

    Most Vibrio species in autochthonous marine microbial communities, such as Vibrio alginolyticus, Vibrio harveyi, Vibrio anguillarum among others, are considered nonpathogenic for humans. However, because many bacterial virulence genes are located in mobile genetic elements, the acquisition of mobile DNA could mediate the appearance of virulent or more virulent strains even in a species defined as nonpathogenic. In this study, we screened a collection of marine nonpathogenic Vibrio strains isolated in the area of the Venetian Lagoon for the presence of virulence and fitness genes usually present in Vibrio cholerae and Vibrio parahaemolyticus clinical isolates. More than one-third of the strains tested positive for the presence of at least one of the potential virulence/fitness genes with the gene encoding the V.cholerae neuraminidase the most frequently detected. Moreover, 13 of the environmental strains carried modified versions of the V.cholerae pathogenicity island VPI-2, and four of them also contained partial fragments of the V.parahaemolyticus Vp-PAI. The data obtained support the view of nonpathogenic Vibrio strains as a significant reservoir of virulence and fitness genes. The emergence of environmental bacteria with new virulence traits might constitute a direct concern for public health and a risk for human health. PMID:22676367

  11. 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

  12. PCR and molecular detection for differentiating Vibrio species.

    PubMed

    Sparagano, O A E; Robertson, P A W; Purdom, I; McInnes, J; Li, Y; Yu, D-H; Du, Z-J; Xu, H-S; Austin, B

    2002-10-01

    Vibriosis is an economically important disease of fish, marine invertebrates (particularly penaeid shrimps), and large marine mammals and is responsible for high mortality rates in aquaculture worldwide. Some Vibrio species are also responsible for zoonoses, whereas others are relatively nonpathogenic. Using 16S- and 23S-based PCR reactions, we obtained species-specific patterns and a 470-bp band, respectively. DNA sequences obtained on the 23S rRNA gene allowed us to identify species-specific probes for Vibrio parahaemolyticus, V. alginolyticus, V. anguillarum and for a cluster of taxonomically related species: V. carchariae/harveyi/campbelii. A phylogenetic tree based on the 23S sequences confirmed previous results obtained by Western blotting. PMID:12381564

  13. Radiofrequency transmission line for bioluminescent Vibrio sp. irradiation

    NASA Astrophysics Data System (ADS)

    Nassisi, V.; Alifano, P.; Tal, 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).

  14. Cinnamaldehyde and cinnamaldehyde derivatives reduce virulence in Vibrio spp. by decreasing the DNA-binding activity of the quorum sensing response regulator LuxR

    PubMed Central

    Brackman, Gilles; Defoirdt, Tom; Miyamoto, Carol; Bossier, Peter; Van Calenbergh, Serge; Nelis, Hans; Coenye, Tom

    2008-01-01

    Background To date, only few compounds targeting the AI-2 based quorum sensing (QS) system are known. In the present study, we screened cinnamaldehyde and substituted cinnamaldehydes for their ability to interfere with AI-2 based QS. The mechanism of QS inhibition was elucidated by measuring the effect on bioluminescence in several Vibrio harveyi mutants. We also studied in vitro the ability of these compounds to interfere with biofilm formation, stress response and virulence of Vibrio spp. The compounds were also evaluated in an in vivo assay measuring the reduction of Vibrio harveyi virulence towards Artemia shrimp. Results Our results indicate that cinnamaldehyde and several substituted derivatives interfere with AI-2 based QS without inhibiting bacterial growth. The active compounds neither interfered with the bioluminescence system as such, nor with the production of AI-2. Study of the effect in various mutants suggested that the target protein is LuxR. Mobility shift assays revealed a decreased DNA-binding ability of LuxR. The compounds were further shown to (i) inhibit biofilm formation in several Vibrio spp., (ii) result in a reduced ability to survive starvation and antibiotic treatment, (iii) reduce pigment and protease production in Vibrio anguillarum and (iv) protect gnotobiotic Artemia shrimp against virulent Vibrio harveyi BB120. Conclusion Cinnamaldehyde and cinnamaldehyde derivatives interfere with AI-2 based QS in various Vibrio spp. by decreasing the DNA-binding ability of LuxR. The use of these compounds resulted in several marked phenotypic changes, including reduced virulence and increased susceptibility to stress. Since inhibitors of AI-2 based quorum sensing are rare, and considering the role of AI-2 in several processes these compounds may be useful leads towards antipathogenic drugs. PMID:18793453

  15. Refined identification of Vibrio bacterial flora from Acanthasther planci based on biochemical profiling and analysis of housekeeping genes.

    PubMed

    Rivera-Posada, J A; Pratchett, M; Cano-Gomez, A; Arango-Gomez, J D; Owens, L

    2011-09-01

    We used a polyphasic approach for precise identification of bacterial flora (Vibrionaceae) isolated from crown-of-thorns starfish (COTS) from Lizard Island (Great Barrier Reef, Australia) and Guam (U.S.A., Western Pacific Ocean). Previous 16S rRNA gene phylogenetic analysis was useful to allocate and identify isolates within the Photobacterium, Splendidus and Harveyi clades but failed in the identification of Vibrio harveyi-like isolates. Species of the V harveyi group have almost indistinguishable phenotypes and genotypes, and thus, identification by standard biochemical tests and 16S rRNA gene analysis is commonly inaccurate. Biochemical profiling and sequence analysis of additional topA and mreB housekeeping genes were carried out for definitive identification of 19 bacterial isolates recovered from sick and wild COTS. For 8 isolates, biochemical profiles and topA and mreB gene sequence alignments with the closest relatives (GenBank) confirmed previous 16S rRNA-based identification: V. fortis and Photobacterium eurosenbergii species (from wild COTS), and V natriegens (from diseased COTS). Further phylogenetic analysis based on topA and mreB concatenated sequences served to identify the remaining 11 V harveyi-like isolates: V. owensii and V. rotiferianus (from wild COTS), and V. owensii, V. rotiferianus, and V. harveyi (from diseased COTS). This study further confirms the reliability of topA-mreB gene sequence analysis for identification of these close species, and it reveals a wider distribution range of the potentially pathogenic V. harveyi group. PMID:22013751

  16. Antibiotic resistance and plasmid profiling of Vibrio spp. in tropical waters of Peninsular Malaysia.

    PubMed

    You, K G; Bong, C W; Lee, C W

    2016-03-01

    Vibrio species isolated from four different sampling stations in the west coast of Peninsular Malaysia were screened for their antimicrobial resistance and plasmid profiles. A total of 138 isolates belonging to 15 different species were identified. Vibrio campbellii, V. parahaemolyticus, V. harveyi, and V. tubiashii were found to predominance species at all stations. High incidence of erythromycin, ampicillin, and mecillinam resistance was observed among the Vibrio isolates. In contrast, resistance against aztreonam, cefepime, streptomycin, sulfamethoxazole, and sulfonamides was low. All the Vibrio isolates in this study were found to be susceptible to imipenem, norfloxacin, ofloxacin, chloramphenicol, trimethoprim/sulfamethoxazole, and oxytetracycline. Ninety-five percent of the Vibrio isolates were resistant to one or more different classes of antibiotic, and 20 different resistance antibiograms were identified. Thirty-two distinct plasmid profiles with molecular weight ranging from 2.2 to 24.8kb were detected among the resistance isolates. This study showed that multidrug-resistant Vibrio spp. were common in the aquatic environments of west coast of Peninsular Malaysia. PMID:26884358

  17. Genetic diversity of culturable Vibrio in an Australian blue mussel Mytilus galloprovincialis hatchery.

    PubMed

    Kwan, Tzu Nin; Bolch, Christopher J S

    2015-09-17

    Bacillary necrosis associated with Vibrio species is the common cause of larval and spat mortality during commercial production of Australian blue mussel Mytilus galloprovincialis. A total of 87 randomly selected Vibrio isolates from various stages of rearing in a commercial mussel hatchery were characterised using partial sequences of the ATP synthase alpha subunit gene (atpA). The sequenced isolates represented 40 unique atpA genotypes, overwhelmingly dominated (98%) by V. splendidus group genotypes, with 1 V. harveyi group genotype also detected. The V. splendidus group sequences formed 5 moderately supported clusters allied with V. splendidus/V. lentus, V. atlanticus, V. tasmaniensis, V. cyclitrophicus and V. toranzoniae. All water sources showed considerable atpA gene diversity among Vibrio isolates, with 30 to 60% of unique isolates recovered from each source. Over half (53%) of Vibrio atpA genotypes were detected only once, and only 7 genotypes were recovered from multiple sources. Comparisons of phylogenetic diversity using UniFrac analysis showed that the culturable Vibrio community from intake, header, broodstock and larval tanks were phylogenetically similar, while spat tank communities were different. Culturable Vibrio associated with spat tank seawater differed in being dominated by V. toranzoniae-affiliated genotypes. The high diversity of V. splendidus group genotypes detected in this study reinforces the dynamic nature of microbial communities associated with hatchery culture and complicates our efforts to elucidate the role of V. splendidus group bacteria in vibriosis. PMID:26378406

  18. First description of 'Chalky back' phenomenon in banana prawns (Fenneropenaeus merguiensis) and its possible association with Vibrio and Photobacterium species.

    PubMed

    Hatje, Eva; Minniti, Giusi; Stewart, Michael J; Neuman, Christina; Knibb, Wayne; Katouli, Mohammad

    2016-02-01

    Here we report a newly identified 'Chalky back' phenomenon in banana prawns (Fenneropenaeus merguiensis) farmed in North Queensland, Australia. This was characterized by localized white discoloured segmentation of the cervical groove, moreover, after cooking the prawns exploded, making them unfit for commercial sale. Histological examination revealed breakdown of gut and abdominal muscle tissue in some moribund specimens. We selectively isolated Vibrio spp., which are known prawn pathogens, from healthy and Chalky back specimens. Isolated bacteria were identified, typed and tested for the presence of eight virulence genes (VGs), biofilm formation, adherence and cytotoxicity to fish cells. In all, 32 isolates were recovered and identified as Vibrio harveyi, V. owensii, V. sinaloensis-like, V. campbellii, V. shilonii, Vibrio sp. and Photobacterium damselae using 16S rRNA gene sequencing. All V. harveyi carried VGs coding for haemolysin, toxR and flagella; formed biofilm; and adhered to both cell lines. This was similar to the V. sinaloensis-like strains that were only isolated from Chalky back specimens. Our data suggest that Vibrio spp. may play a role in the pathogenesis of Chalky back. This study is the first report of Chalky back phenomenon in farmed banana prawns that needs to be closely monitored by the industry. PMID:26825678

  19. 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, ...

  20. Reducing Vibrio load in Artemia nauplii using antimicrobial photodynamic therapy: a promising strategy to reduce antibiotic application in shrimp larviculture

    PubMed Central

    Asok, Aparna; Arshad, Esha; Jasmin, C.; Somnath Pai, S.; Bright Singh, I. S.; Mohandas, A.; Anas, Abdulaziz

    2012-01-01

    Summary We propose antimicrobial photodynamic therapy (aPDT) as an alternative strategy to reduce the use of antibiotics in shrimp larviculture systems. The growth of a multiple antibiotic resistant Vibrio harveyi strain was effectively controlled by treating the cells with Rose Bengal and photosensitizing for 30 min using a halogen lamp. This resulted in the death of > 50% of the cells within the first 10 min of exposure and the 50% reduction in the cell wall integrity after 30 min could be attributed to the destruction of outer membrane protein of V. harveyi by reactive oxygen intermediates produced during the photosensitization. Further, mesocosm experiments with V. harveyi and Artemia nauplii demonstrated that in 30 min, the aPDT could kill 78.9% and 91.2% of heterotrophic bacterial and Vibrio population respectively. In conclusion, the study demonstrated that aPDT with its rapid action and as yet unreported resistance development possibilities could be a propitious strategy to reduce the use of antibiotics in shrimp larviculture systems and thereby, avoid their hazardous effects on human health and the ecosystem at large. PMID:21951316

  1. Vibrios adhere to epithelial cells in the intestinal tract of red sea bream, Pagrus major, utilizing GM4 as an attachment site.

    PubMed

    Chisada, Shin-ichi; Shimizu, Kohei; Kamada, Haruna; Matsunaga, Naoyuki; Okino, Nozomu; Ito, Makoto

    2013-04-01

    Vibrios, distributed in marine and brackish environments, can cause vibriosis in fish and shellfish under appropriate conditions. Previously, we clarified by thin-layer chromatography (TLC) overlay assay that (35)S-labeled Vibrio trachuri adhered to GM4 isolated from red sea bream intestine. However, whether GM4 actually functions on epithelial cells as an attachment site for vibrios still remains to be uncovered. We found that six isolates, classified as V. harveyi, V. campbellii, and V. splendidus, from intestinal microflora of red sea bream adhered to GM4 but not galactosylceramide (GalCer) by TLC-overlay assay. Tissue-overlay assays revealed that V. harveyi labeled with green fluorescent protein (GFP) adhered to epithelial cells of red sea bream intestine where GM4 and GalCer were found to be distributed on the top layer of actin filaments by immunohistochemical analysis using corresponding antibodies. The number of adhering vibrios was diminished by pretreatment with anti-GM4 antibody, but not anti-GalCer antibody. These results clearly indicate that vibrios adhere to epithelial cells of red sea bream intestine utilizing GM4 as an attachment site. PMID:23320941

  2. Siderophore production by Vibrio vulnificus.

    PubMed Central

    Simpson, L M; Oliver, J D

    1983-01-01

    Previous studies in our laboratory, as well as clinical evidence, have suggested that increased iron levels in the host may be important in infections caused by the halophilic pathogen Vibrio vulnificus. To study iron acquisition, we induced siderophore production by growth in a low-iron medium, and biochemical testing indicated the production of both hydroxamate- and phenolate-type siderophores. The siderophores were extracted from growth filtrates with ethyl acetate (for phenolates) and phenol-chloroform-ether (for hydroxamates). These extracts enhanced the growth of V. vulnificus when the bacterium was grown in iron-limited medium. The ability of these siderophores to stimulate the growth of Salmonella typhimurium LT-2 enb-7 (a mutant deficient in the biosynthesis of enterochelin) and Arthrobacter flavescens JG-9 (a hydroxamate auxotroph) supported the conclusion that V. vulnificus produces both hydroxamate- and phenolate-type siderophores. PMID:6223882

  3. Vibrio infections triggering mass mortality events in a warming Mediterranean Sea.

    PubMed

    Vezzulli, Luigi; Previati, Monica; Pruzzo, Carla; Marchese, Anna; Bourne, David G; Cerrano, Carlo

    2010-07-01

    Mass mortality events of benthic invertebrates in the temperate north-western (NW) Mediterranean Sea have been observed in recent seasons. A 16 month in situ study in the Ligurian Sea (NW Mediterranean Sea) demonstrated that the occurrence of Paramuricea clavata mortality episodes were concomitant to a condition of prolonged high sea surface temperatures, low chlorophyll concentrations and the presence of culturable Vibrio spp. in seawater. The occurrence of Vibrio spp. at the seasonal scale was correlated with temperature; with few vibrios retrieved on specific media when the temperature dropped below 18 degrees C and a sharp increase of vibrios abundance (up to 3.4 x 10(4) MPN l(-1)) when the temperature was greater than or equal to 22 degrees C. Phylogenetic and phenotypic analysis of Vibrio isolates associated with healthy and diseased P. clavata colonies collected during a mortality episode showed that these bacteria were significantly more abundant in diseased than in healthy corals and were related to the V. harveyi, V. splendidus and V. coralliilyticus groups, the latter only identified in diseased organisms. Inoculation of bacterial isolates from these groups onto healthy P. clavata in aquaria caused disease signs and death in a range of Vibrio concentrations, temperature values and trophic conditions consistent with those recorded in the field. It is concluded that Vibrio infections may act as an additional triggering mechanism of mass mortality events in the coastal Mediterranean Sea and that their occurrence is climate-linked. Predicted global warming leading to long-lasting hot summer periods together with stratification resulting in energetic constraints represent a major threat to the survival of benthic invertebrates in the temperate NW Mediterranean Sea due to potential disease outbreak associated with Vibrio pathogens. PMID:20370818

  4. 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…

  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. An in silico, in vitro and in vivo investigation of indole-3-carboxaldehyde identified from the seawater bacterium Marinomonas sp. as an anti-biofilm agent against Vibrio cholerae O1.

    PubMed

    Rajalaxmi, Murugan; Beema Shafreen, Rajamohamed; Iyer, Prasanth M; Sahaya Vino, Raja; Balamurugan, Krishnaswamy; Pandian, Shunmugiah Karutha

    2016-04-01

    Biofilm formation is a major contributing factor in the pathogenesis of Vibrio cholerae O1 (VCO1) and therefore preventing biofilm formation could be an effective alternative strategy for controlling cholera. The present study was designed to explore seawater bacteria as a source of anti-biofilm agents against VCO1. Indole-3-carboxaldehyde (I3C) was identified as an active principle component in Marinomonas sp., which efficiently inhibited biofilm formation by VCO1 without any selection pressure. Furthermore, I3C applications also resulted in considerable collapsing of preformed pellicles. Real-time PCR studies revealed the down-regulation of virulence gene expression by modulation of the quorum-sensing pathway and enhancement of protease production, which was further confirmed by phenotypic assays. Furthermore, I3C increased the survival rate of Caenorhabditis elegans when infected with VCO1 by significantly reducing in vivo biofilm formation, which was corroborated by a survivability assay. Thus, this study revealed, for the first time, the potential of I3C as an anti-biofilm agent against VCO1. PMID:26939983

  7. Fimbrolide Natural Products Disrupt Bioluminescence of Vibrio By Targeting Autoinducer Biosynthesis and Luciferase Activity.

    PubMed

    Zhao, Weining; Lorenz, Nicola; Jung, Kirsten; Sieber, Stephan A

    2016-01-01

    Vibrio is a model organism for the study of quorum sensing (QS) signaling and is used to identify QS-interfering drugs. Naturally occurring fimbrolides are important tool compounds known to affect QS in various organisms; however, their cellular targets have so far remained elusive. Here we identify the irreversible fimbrolide targets in the proteome of living V.?harveyi and V.?campbellii via quantitative mass spectrometry utilizing customized probes. Among the major hits are two protein targets with essential roles in Vibrio QS and bioluminescence. LuxS, responsible for autoinducer?2 biosynthesis, and LuxE, a subunit of the luciferase complex, were both covalently modified at their active-site cysteines leading to inhibition of activity. The identification of LuxE unifies previous reports suggesting inhibition of bioluminescence downstream of the signaling cascade and thus contributes to a better mechanistic understanding of these QS tool compounds. PMID:26609793

  8. Interaction of Vibrio spp. with the Inner Surface of the Digestive Tract of Penaeus monodon

    PubMed Central

    Soonthornchai, Wipasiri; Chaiyapechara, Sage; Jarayabhand, Padermsak; Söderhäll, Kenneth; Jiravanichpaisal, Pikul

    2015-01-01

    Several species of Vibrio are the causative agent of gastroenteritis in humans. In aquaculture, Vibrio harveyi (Vh) and V. parahaemolyticus (Vp) have long been considered as shrimp pathogens in freshwater, brackish and marine environments. Here we show by using scanning electron microscopy (SEM) that Penaeus monodon orally inoculated with each of these two pathogens via an Artemia diet had numerous bacteria attached randomly across the stomach surface, in single and in large biofilm-like clusters 6 h post-infection. A subsequent marked proliferation in the number of V. harveyi within the biofilm-like formations resulted in the development of infections in the stomach, the upper and middle midgut, but neither in the posterior midgut nor the hindgut. SEM also revealed the induced production of peritrichous pili-like structures by the Vp attaching to the stomach lining, whilst only a single polar fibre was seen forming an apparent physical bridge between Vh and the host’s epithelium. In contrast to these observations, no such adherences or linkages were seen when trials were conducted with non-pathogenic Vibrio spp. or with Micrococcus luteus, with no obvious resultant changes to the host’s gut surface. In naive shrimp, the hindgut was found to be a favorable site for bacteria notably curved, short-rod shaped bacteria which probably belong to Vibrio spp. Data from the current study suggests that pathogens of P. monodon must be able to colonize the digestive tract, particularly the stomach, where chitin is present, and then they use an array of virulent factors and enzymes to infect their host resulting in disease. Oral infection is a better way of mimicking natural routes of infection; investigating the host-bacteria interactions occurring in the digestive tract may lead to new strategies for the prevention or control of bacterial infections in penaeids. PMID:26285030

  9. Interaction of Vibrio spp. with the Inner Surface of the Digestive Tract of Penaeus monodon.

    PubMed

    Soonthornchai, Wipasiri; Chaiyapechara, Sage; Jarayabhand, Padermsak; Söderhäll, Kenneth; Jiravanichpaisal, Pikul

    2015-01-01

    Several species of Vibrio are the causative agent of gastroenteritis in humans. In aquaculture, Vibrio harveyi (Vh) and V. parahaemolyticus (Vp) have long been considered as shrimp pathogens in freshwater, brackish and marine environments. Here we show by using scanning electron microscopy (SEM) that Penaeus monodon orally inoculated with each of these two pathogens via an Artemia diet had numerous bacteria attached randomly across the stomach surface, in single and in large biofilm-like clusters 6 h post-infection. A subsequent marked proliferation in the number of V. harveyi within the biofilm-like formations resulted in the development of infections in the stomach, the upper and middle midgut, but neither in the posterior midgut nor the hindgut. SEM also revealed the induced production of peritrichous pili-like structures by the Vp attaching to the stomach lining, whilst only a single polar fibre was seen forming an apparent physical bridge between Vh and the host's epithelium. In contrast to these observations, no such adherences or linkages were seen when trials were conducted with non-pathogenic Vibrio spp. or with Micrococcus luteus, with no obvious resultant changes to the host's gut surface. In naive shrimp, the hindgut was found to be a favorable site for bacteria notably curved, short-rod shaped bacteria which probably belong to Vibrio spp. Data from the current study suggests that pathogens of P. monodon must be able to colonize the digestive tract, particularly the stomach, where chitin is present, and then they use an array of virulent factors and enzymes to infect their host resulting in disease. Oral infection is a better way of mimicking natural routes of infection; investigating the host-bacteria interactions occurring in the digestive tract may lead to new strategies for the prevention or control of bacterial infections in penaeids. PMID:26285030

  10. Vibrio fischeri metabolism: symbiosis and beyond.

    PubMed

    Dunn, Anne K

    2012-01-01

    Vibrio fischeri is a bioluminescent, Gram-negative marine bacterium that can be found free living and in a mutualistic association with certain squids and fishes. Over the past decades, the study of V. fischeri has led to important discoveries about bioluminescence, quorum sensing, and the mechanisms that underlie beneficial host-microbe interactions. This chapter highlights what has been learned about metabolic pathways in V. fischeri, and how this information contributes to a broader understanding of the role of bacterial metabolism in host colonization by both beneficial and pathogenic bacteria, as well as in the growth and survival of free-living bacteria. PMID:23046951

  11. Intestinal Colonization Dynamics of Vibrio cholerae

    PubMed Central

    Almagro-Moreno, Salvador; Pruss, Kali; Taylor, Ronald K.

    2015-01-01

    To cause the diarrheal disease cholera, Vibrio cholerae must effectively colonize the small intestine. In order to do so, the bacterium needs to successfully travel through the stomach and withstand the presence of agents such as bile and antimicrobial peptides in the intestinal lumen and mucus. The bacterial cells penetrate the viscous mucus layer covering the epithelium and attach and proliferate on its surface. In this review, we discuss recent developments and known aspects of the early stages of V. cholerae intestinal colonization and highlight areas that remain to be fully understood. We propose mechanisms and postulate a model that covers some of the steps that are required in order for the bacterium to efficiently colonize the human host. A deeper understanding of the colonization dynamics of V. cholerae and other intestinal pathogens will provide us with a variety of novel targets and strategies to avoid the diseases caused by these organisms. PMID:25996593

  12. Induction of melanin biosynthesis in Vibrio cholerae.

    PubMed Central

    Coyne, V E; al-Harthi, L

    1992-01-01

    Vibrio cholerae synthesized the pigment melanin in response to specific physiological conditions that were stressful to the bacterium. Pigmentation was induced when V. cholerae was subjected to hyperosmotic stress in conjunction with elevated growth temperatures (above 30 degrees C). The salt concentration tolerated by V. cholerae was lowered by additional abiotic factors such as acidic starting pH of the growth medium and limitation of organic nutrients. Although the amount of toxin detected in the culture supernatant decreased significantly in response to stressful culture conditions, no correlation between the physiological conditions that induced melanogenesis and expression of OmpU or cholera toxin was detected. Since conditions that induce melanin production in V. cholerae occur in both the aquatic environment and the human host, it is possible that melanogenesis has a specific function with respect to the survival of the bacterium in these habitats. PMID:1444398

  13. Sixty years from the discovery of Vibrio parahaemolyticus and some recollections.

    PubMed

    Shinoda, Sumio

    2011-12-01

    Vibrio parahaemolyticus was discovered by Tsunesaburo Fujino after a shirasu food poisoning outbreak in 1950, but at that time the isolate was named Pasteurella parahaemolytica, not Vibrio. Although the isolate resembled Vibrio, some properties did not correspond with those of Vibrio. For example, the curved cell form of the cell was one of the important taxonomical indicators of the genus, but the isolate was straight in form. After 5 years, Iwao Takikawa isolated a similar bacterium from a food poisoning case and found the halophilic property of the isolate. He named the isolate Pseudomonas enteritis. In 1960, due to the progress of taxonomy, various scientific indices were adjusted, and Davis and Parks defined the taxonomical position of the genus Vibrio, and Fujino et al. and Sakazaki et al. reexamined the above isolates and confirmed that those were the same species in the genus Vibrio and proposed the new scientific name Vibrio parahaemolyticus.Last year was the 60th year since the discovery of the bacterium, and the discoverer was the first president of our organization, the Society for Antibacterial and Antifungal Agents, Japan. Some recollections including the correlation between the Kanagawa phenomenon and human pathogenicity, the major pathogenic factor TDH (thermostable direct hemolysin) and its related hemolysin (TRH: TDH related hemolysin) are also summarized. PMID:22190435

  14. [Selection of cross-protective antigens from outer membrane proteins of three pathogenic vibrios isolated from infected large yellow croaker (Pseudosciaena crocea)].

    PubMed

    Zhang, Chongwen; Mao, Zhijuan; Yu, Lian

    2012-12-01

    Vibrios are universal conditioned-pathogenic bacteria in marine culture environment, and the outbreak of vibrio disease resulted in a serious damage to aquaculture. Considering that vibrio disease in aquatic species, especially fishes, usually originated from mixed infection of different species (serotypes or subspecies) of vibrios, it is important to select the potential cross-protective protein antigens as candidates of polyvalent or combined vaccines. In present research, several strains of vibrios were isolated from infected large yellow croaker (Pseudosciaena crocea) and subsequently identified as six strains of V. harveyi, one V. parahaemolyticus and one V. alginolyticus by physiological, biochemical and molecular biological methods. Their outer membrane proteins (OMPs) were extracted and the SDS-PAGE and Western blotting results show that three immuno-blots with common molecular weight presented at approximate 45 kDa, 35 kDa and 22 kDa on their OMP electrophoretogram, indicating the existence of antigens with cross-protection in their OMPs. With the aids of combination of two-dimensional electrophoresis (2-D) and Western blotting and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), a deduced porin (GenBank Accession No. ZP_01260407) from V. alginolyticus and a maltoporin precursor (GenBank Accession No. NP_801154) from V. parahaemolyticus were able to react with polyclonal antibody to whole V. harveyi, suggesting these two proteins could act as the cross-protective antigens and the vaccines prepared with these porins would be probable to bring cross protection to three different vibrios. PMID:23593870

  15. Vibrio and Pregnancy

    MedlinePLUS

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

  16. Isolation and characterization of luminescent bacterium for sludge biodegradation.

    PubMed

    Zahaba, Maryam; Halmi, Mohd Izuan Effendi; Ahmad, Siti Aqlima; Shukor, Mohd Yunus; Syed, Mohd Arif

    2015-11-01

    Microtox is based on the inhibition of luminescence of the bacterium Vibrio fischeri by the toxicants. This technique has been accepted by the USEPA (United States Environmental Protection Agency) as a biomonitoring tool for remediation of toxicants such as hydrocarbon sludge. In the present study, a luminescent bacterium was isolated from yellow striped scad (Selaroides leptolepis) and was tentatively identified as Vibrio sp. isolate MZ. This aerobic isolate showed high luminescence activity in a broad range of temperature from 25 to 35 °C. In addition, optimal conditions for high bioluminescence activity in range of pH 7.5 to 8.5 and 10 gl(-1) of sodium chloride, 10 gl(-1) of peptone and 10 gl(-1) of sucrose as carbon source. Bench scale biodegradation 1% sludge (w/v) was set up and degradation was determined using gas chromatography with flame ionised detector (GC-FID). In this study, Rhodococcus sp. strain AQ5NOL2 was used to degrade the sludge. Based on the preliminary results obtained, Vibrio sp. isolate MZwas able to monitor the biodegradation of sludge. Therefore, Vibrio sp. isolate MZ has the potential to be used as a biomonitoring agent for biomonitoring of sludge biodegradation particularly in the tropical ranged environment. PMID:26688958

  17. Prevalence and antimicrobial susceptibility of Vibrio parahaemolyticus isolated from retail shellfish in Shanghai

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vibrio parahaemolyticus is a marine and estuarine bacterium that poses a large threat to human health worldwide. It has been the leading bacterial cause of seafood-borne illness. This study investigated the prevalence and drug resistance of V. parahaemolyticus isolated from retail shellfish in Shang...

  18. 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...

  19. 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

  20. Enzymatic characterization of Vibrio alginolyticus strains isolated from bivalves harvested at Venice Lagoon (Italy) and Guanabara Bay (Brazil).

    PubMed

    Lafisca, Andrea; Pereira, Christiane Soares; Giaccone, Valrio; Rodrigues, Dalia dos Prazeres

    2008-01-01

    The aquatic ecosystem is the natural habitat of microorganisms including Vibrio and Aeromonas genus which are pathogenic to human and animals. In the present investigation the frequency of these bacteria and the enzymatic characteristics of 34 Vibrio alginolyticus strains isolated from bivalves harvested in Venice Lagoon (Italy) and Guanabara Bay (Brazil) were carried out from November 2003 to February 2004. The mussels' samples were submitted to enrichment in Alkaline Peptone Water (APW) added with 1% of sodium chloride (NaCl) and APW plus 3% NaCl incubated at 37 degrees C for 18-24 h. Following the samples were streaked onto TCBS Agar (Thiossulfate Citrate Bile Sucrose Agar) and the suspected colonies were submitted to biochemical characterization. Also, the Vibrio alginolyticus strains were evaluated to collagenase, elastase and chondroitinase production. The results showed the isolation of 127 microorganisms distributed as follows: 105 Vibrio strains such as V. alginolyticus (32.4%), V. harveyi (19%) and V. parahaemolyticus (7.6%), 20 Aeromonas strains and two Plesiomonas shigelloides were the main pathogens isolated. We observed the production of the three enzymes from V. alginolyticus strains considered as the main virulence factors of the bacteria, especially in cases of human dermatological infection. PMID:18813756

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

    PubMed

    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

    2012-04-01

    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

  2. Environmental determinants of Vibrio cholerae biofilm development.

    PubMed

    Kierek, Katharine; Watnick, Paula I

    2003-09-01

    Vibrio cholerae is a versatile bacterium that flourishes in diverse environments, including the human intestine, rivers, lakes, estuaries, and the ocean. Surface attachment is believed to be essential for colonization of all of these natural environments. Previous studies have demonstrated that the vps genes, which encode proteins required for exopolysaccharide synthesis and transport, are required for V. cholerae biofilm development in Luria-Bertani broth. In this work, we showed that V. cholerae forms vps-dependent biofilms and vps-independent biofilms. The vps-dependent and -independent biofilms differ in their environmental activators and in architecture. Our results suggest that environmental activators of vps-dependent biofilm development are present in freshwater, while environmental activators of vps-independent biofilm development are present in seawater. The distinct environmental requirements for the two modes of biofilm development suggest that vps-dependent biofilm development and vps-independent biofilm development may play distinct roles in the natural environment. PMID:12957889

  3. 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

  4. Environmental Vibrio parahaemolyticus DNA signatures validation.

    PubMed

    Caburlotto, G; Knight, I T; Lleo, M M; Taviani, E; Huq, A; Colwell, R R

    2011-12-01

    Insignia is a novel DNA computational system which uses highly efficient algorithms to compare bacterial genomes and to identify specific DNA signatures to distinguish a target bacterium, or group of bacteria, from all other known bacterial species. It is currently being validated using different bacterial groups, including Vibrio spp. In this study, the genomic analysis by Insignia was conducted on Vibrio parahaemolyticus, a halophilic gram-negative bacteria which constitutes a leading cause of seafood-borne disease. Insignia was used to identify 37 V. parahaemolyticus-specific signatures and to design PCR assays to validate the representative signature sequences by TaqMan essays. The 37 assays targeted loci distributed around the genome and detected genes coding for hypothetical proteins and for proteins involved in adhesion, starvation and virulence. A panel of V. parahaemolyticus environmental strains isolated from the North Adriatic Sea (Italy) and from the Black Sea (Georgia) was used to validate the selected signatures. The signature assays revealed both sensitive and specific and the method allowed a more accurate identification of the tested bacterial strains at the species level when compared to biochemical and PCR standard methods. Using Insignia, it was possible to distinguish two different groups among the strains previously identified as V. parahaemolyticus: most of the strains were included in a "V. parahaemolyticus-like group" showing nearly all of the signatures assayed while a small group of 10 strains contained only a few of the signatures tested. By sequencing the 16S rDNA of this latter group, it was confirmed that they were not V. parahaemolyticus but in fact belonged to other Vibrio species. No significant genome-wide differences were detected between the strains isolated in Italy and in Georgia though the very different geographical origin. PMID:21940129

  5. Three vibrio-resistance related EST-SSR markers revealed by selective genotyping in the clam Meretrix meretrix.

    PubMed

    Nie, Qing; Yue, Xin; Chai, Xueliang; Wang, Hongxia; Liu, Baozhong

    2013-08-01

    The clam Meretrix meretrix is an important commercial bivalve distributed in the coastal areas of South and Southeast Asia. In this study, marker-trait association analyses were performed based on the stock materials of M. meretrix with different vibrio-resistance profile obtained by selective breeding. Forty-eight EST-SSR markers were screened and 27 polymorphic SSRs of them were genotyped in the clam stocks with different resistance to Vibrio parahaemolyticus (11-R and 11-S) and to Vibrio harveyi (09-R and 09-C). Allele frequency distributions of the SSRs among different stocks were compared using Pearson's Chi-square test, and three functional EST-SSR markers (MM959, MM4765 and MM8364) were found to be associated with vibrio-resistance trait. The 140-bp allele of MM959 and 128-bp allele of MM4765 had significantly higher frequencies in resistant groups (11-R and 09-R) than in susceptive/control groups (11-S and 09-C) (P < 0.01), which suggested that the clams carrying these two alleles have stronger resistance against vibrio. Clam individuals of 11-S were divided into three subgroups based on the survival time post-challenge, and the multi-dimensional scaling (MDS) analysis showed that clusters generated by genetic similarity revealed by the three SSR markers were consistent with the three subgroups distinctions. The putative functions of contig959, contig4765 and contig8364 also suggested that the three SSR-involved genes might play important roles in immunity of M. meretrix. All these results supported that EST-SSR markers MM959, MM4765 and MM8364 were associated with vibrio-resistance and would be useful for marker-assisted selection (MAS) in M. meretrix genetic breeding. PMID:23707743

  6. Substrate specificity and function of the pheromone receptor AinR in Vibrio fischeri ES114.

    PubMed

    Kimbrough, John H; Stabb, Eric V

    2013-11-01

    Two distinct but interrelated pheromone-signaling systems, LuxI/LuxR and AinS/AinR, positively control bioluminescence in Vibrio fischeri. Although each system generates an acyl-homoserine lactone (AHL) signal, the protein sequences of LuxI/LuxR and AinS/AinR are unrelated. AinS and LuxI generate the pheromones N-octanoyl-AHL (C8-AHL) and N-3-oxo-hexanoyl-AHL (3OC6-AHL), respectively. LuxR is a transcriptional activator that responds to 3OC6-AHL, and to a lesser extent to C8-AHL. AinR is hypothesized to respond to C8-AHL and, based on homology to Vibrio harveyi LuxN, to mediate the repression of a Qrr regulatory RNA. However, a ?ainR mutation decreased luminescence, which was not predicted based on V. harveyi LuxN, raising the possibility of a distinct regulatory mechanism for AinR. Here we show that ainR can complement a luxN mutant, suggesting functional similarity. Moreover, in V. fischeri, we observed ainR-dependent repression of a Pqrr-lacZ transcriptional reporter in the presence of C8-AHL, consistent with its hypothesized regulatory role. The system appears quite sensitive, with a half-maximal effect on a Pqrr reporter at 140 pM C8-AHL. Several other AHLs with substituted and unsubstituted acyl chains between 6 and 10 carbons also displayed an AinR-dependent effect on Pqrr-lacZ; however, AHLs with acyl chains of four carbons or 12 or more carbons lacked activity. Interestingly, 3OC6-AHL also affected expression from the qrr promoter, but this effect was largely luxR dependent, indicating a previously unknown connection between these systems. Finally, we propose a preliminary explanation for the unexpected luminescence phenotype of the ?ainR mutant. PMID:24056099

  7. The interactions of Vibrio vulnificus and the oyster Crassostrea virginica.

    PubMed

    Froelich, Brett; Oliver, James D

    2013-05-01

    The human bacterial pathogen, Vibrio vulnificus, is found in brackish waters and is concentrated by filter-feeding molluscan shellfish, especially oysters, which inhabit those waters. Ingestion of raw or undercooked oysters containing virulent strains of V. vulnificus can result in rapid septicemia and death in 50 % of victims. This review summarizes the current knowledge of the environmental interactions between these two organisms, including the effects of salinity and temperature on colonization, uptake, and depuration rates of various phenotypes and genotypes of the bacterium, and host-microbe immunological interactions. PMID:23280497

  8. RAPID TETRAZOLIUM DYE REDUCTION ASSAY TO ASSESS THE BACTERICIDAL ACTIVITY OF OYSTER (CRASSOSTREA VIRGINICA) HEMOCYTES AGAINST VIBRIO PARAHAEMOLYTICUS

    EPA Science Inventory

    An assay was developed to assess the ability of oyster, Crassostrea virginica, hemocytes to kill the human pathogenic bacterium, Vibrio parahaemolyticus (ATCC 17802). Bacterial killing was estimated colorimetrically by the enzymatic reduction of a tetrazolium dye, 3-(4,5-dimethyl...

  9. Draft Genome Sequence of Vibrio coralliilyticus Strain OCN008, Isolated from K?neohe Bay, Hawaii

    PubMed Central

    Ushijima, Blake; Videau, Patrick; Aeby, Greta S.

    2013-01-01

    Vibrio coralliilyticus is a Gram-negative bacterium found in seawater and is associated with diseased marine organisms. Strains of V.coralliilyticus have been shown to infect coral from multiple genera. We report the draft genome sequence of V.coralliilyticus strain OCN008, the third V.coralliilyticus genome to be sequenced. PMID:24092784

  10. Mortalities of Eastern and Pacific Oyster Larvae Caused by the Pathogens Vibrio coralliilyticus and Vibrio tubiashii

    PubMed Central

    Watson, Michael A.; Needleman, David S.; Church, Karlee M.; Häse, Claudia C.

    2014-01-01

    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 × 104 to 3.0 × 104 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 × 104 and 4.0 × 104 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 × 104 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

  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. Description of a Novel Symbiotic Bacterium from the Brittle Star, Amphipholis squamata

    PubMed Central

    Lesser, Michael P.; Blakemore, Richard P.

    1990-01-01

    A gram-negative, marine, facultatively anaerobic bacterial isolate designated strain AS-1 was isolated from the subcuticular space of the brittle star, Amphipholis squamata. Its sensitivity to O/129 and novobiocin, overall morphology, and biochemical characteristics and the moles percent guanine-plus-cytosine composition of its DNA (42.9 to 44.4) suggest that this isolate should be placed in the genus Vibrio. Strain AS-1 was not isolated from ambient seawater and is distinct from described Vibrio species. This symbiotic bacterium may assist its host as one of several mechanisms of nutrient acquisition during the brooding of developing embryos. Images PMID:16348257

  13. [Phages of halophilic vibrios].

    PubMed

    Libinzon, A E; Us, Z I; Gal'tseva, G V; Degtiareva, B M; Golkovski?, G M

    1995-01-01

    The morphology and antigenic properties of 34 phages of Vibrio parahaemolyticus and V. alginolyticus strains isolated from Black Sea water, as well as their range of lytic activity and specificity of action, have been studied. Most of these phages have been found to lyze both V. parahaemolyticus and V. alginolyticus strains. In addition, highly specific phages capable of lyzing only V. parahaemolyticus serotype O5:K15, have been detected. The latter fact is a precedent indicating the possibility of search for other typing phages and the development of the scheme for the phage typing of V. parahaemolyticus in future. PMID:7778366

  14. Vibrio viscosus in farmed Atlantic salmon Salmo salar in Scotland: field and experimental observations.

    PubMed

    Bruno, D W; Griffiths, J; Petrie, J; Hastings, T S

    1998-11-30

    Winter mortality occurred in market-sized (2 to 3 kg) Atlantic salmon Salmo salar reared in sea cages in Scottish waters. Many of the fish had skin ulcers. Internally prominent dark-brown petechiae or ecchymotic haemorrhage was observed. Splenomegaly was associated with congestion and widespread necrosis. A Vibrio sp. was isolated from internal organs. Biochemically isolates of the bacterium were similar to a previously described bacterium, Vibrio viscosus, recorded in a phenotypic study from farmed salmon in Norway. This work examines the occurrence of V. viscosus in marine-reared Atlantic salmon for the first time in Scottish waters. An experimental study reproduced the field observations and Koch's postulates were fulfilled. The histopathology associated with natural infection was compared with that in laboratory-infected fish. PMID:9891731

  15. Vibrio vulnificus: death on the half shell. A personal journey with the pathogen and its ecology.

    PubMed

    Oliver, James D

    2013-05-01

    Vibrio vulnificus is an estuarine bacterium which occurs in high numbers in filter-feeding molluscan shellfish, such as oysters. In individuals with certain underlying diseases, ingestion of the bacterium, e.g., in raw or undercooked oysters, can lead to a rapid and extremely fatal infection. Indeed, this one bacterium is responsible for 95 % of all seafood-borne deaths. In addition, the bacterium is capable of entering a preexisting lesion or cut obtained during coastal recreational activities, resulting in potentially fatal wound infections. This brief review, which comprised a presentation made at the Gordon Research Conference on "Oceans and Human Health," reflects over 35 years of research on this bacterium in the author's laboratory. It describes some of the known virulence factors and why males account for ca 85 % of all V. vulnificus cases. It notes the two genotypes now known to exist and how this pathogen enters a dormant, "viable but nonculturable" state during the winter months. Finally, the review discusses how global warming may be causing worldwide increases in the frequency and geographical extent of Vibrio infections. PMID:23263234

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

    SciTech Connect

    Rivera, S.; Lugo, T.; Hazen, T.C.

    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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 (Vp) and Vibrio vulnificus (Vv) were assessed in natural seawater and in the Eastern oyster...

  18. Identification of capsule, biofilm, lateral flagellum, and type IV pili in Vibrio mimicus strains.

    PubMed

    Tercero-Alburo, J J; Gonzlez-Mrquez, H; Bonilla-Gonzlez, E; Quiones-Ramrez, E I; Vzquez-Salinas, C

    2014-11-01

    Vibrio mimicus is a bacterium that causes gastroenteritis; it is closely related to Vibrio cholerae, and can cause acute diarrhea like cholera- or dysentery-type diarrhea. It is distributed worldwide. Factors associated with virulence (such as hemolysins, enterotoxins, proteases, phospholipases, aerobactin, and hemagglutinin) have been identified; however, its pathogenicity mechanism is still unknown. In pathogenic Vibrio species such as V.cholerae, Vibrio. parahaemolyticus and Vibrio vulnificus, capsule, biofilms, lateral flagellum, and type IV pili are structures described as essential for pathogenicity. These structures had not been described in V.mimicus until this work. We used 20 V.mimicus strains isolated from water (6), oyster (9), and fish (5) samples and we were able to identify the capsule, biofilm, lateral flagellum, and type IV pili through phenotypic tests, electron microscopy, PCR, and sequencing. In all tested strains, we observed and identified the presence of capsular exopolysaccharide, biofilm formation in an invitro model, as well as swarming, multiple flagellation, and pili. In addition, we identified homologous genes to those described in other bacteria of the genus in which these structures have been found. Identification of these structures in V.mimicus is a contribution to the biology of this organism and can help to reveal its pathogenic behavior. PMID:25246027

  19. [The vibrio-static test with niclosamide to identify bacteria of genus Vibrio].

    PubMed

    Sivolodskiy, E P

    2014-05-01

    The new vibrio-static niclosamide (CAS No 50-65-7) is revealed. The vibrio-static test with niclosamide (10 mkg/disc) to identify bacteria of genus Vibrio is developed. This test by its diagnostic sensitivity surpasses the vibrio-static test with vibrio-static O129 since it suppresses growth of vibrios having cross resistance to O129 and co-trimoxazole. The vibrio-static test with niclosamide made it possible to identify all examined strains of V. metschnikovii, V. vulnificus, V. parahaemolyticus, V. cholerae non O1/non O139. PMID:25338465

  20. 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, 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. Lauga, E., DiLuzio, W. R., Whitesides, G. M., Stone, H. A. Biophys. J. 90, 400 (2006).

  1. Lower extremity manifestations of Vibrio vulnificus infection.

    PubMed

    Laughlin, T J; Lavery, L A

    1995-01-01

    Vibrio vulnificus is a potentially lethal marine bacterium that has not been previously described in podiatric literature. A review of the microorganism's characteristics, susceptible patient population, and lower extremity manifestations of infection is presented. V. vulnificus is found as part of the normal flora of the Gulf of Mexico, Atlantic, and Pacific coastal waters and is often isolated from the filter feeding shellfish of these regions. Its pathogenicity is generally reserved for the immunocompromised host, and is specifically related to disease states which exhibit high serum iron levels. V. vulnificus infections present in two distinct clinical syndromes: primary sepsis secondary to raw oyster ingestion, or localized infection from wound exposure to V. vulnificus-inhabited salt water. Both syndromes demonstrate characteristic skin lesions of the trunk and extremities that present as hemorrhagic bullae and progress to necrotic ulcerations. Although V. vulnificus infection is rare, its extreme virulence in patients suffering from a chronic disease process and its manifestation of characteristic lower-extremity lesions require the podiatric physician to be able to recognize and treat such a condition. PMID:7488992

  2. Vibrio parahaemolyticus ToxRS regulator is required for stress tolerance and colonization in a novel orogastric streptomycin-induced adult murine model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vibrio parahaemolyticus, a marine bacterium, is the causative agent of gastroenteritis associated with the consumption of seafood. It contains a homologue of the toxRS operon that in V. cholerae is the key regulator of virulence gene expression. We examined a non-polar mutation in toxRS to determi...

  3. 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

  4. 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

  5. Quantification of Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholerae in French Mediterranean coastal lagoons

    PubMed Central

    Cantet, Franck; Hervio-Heath, Dominique; Caro, Audrey; Le Mennec, Ccile; Monteil, Caroline; Qumr, Catherine; Jolivet-Gougeon, Anne; Colwell, Rita R.; Monfort, Patrick

    2014-01-01

    Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholerae are human pathogens. Little is known about these Vibrio spp. in the coastal lagoons of France. The purpose of this study was to investigate their incidence in water, shellfish and sediment of three French Mediterranean coastal lagoons using the most probable number-polymerase chain reaction (MPN-PCR). In summer, the total number of V. parahaemolyticus in water, sediment, mussels and clams collected from the three lagoons varied from 1 to >1.1 103 MPN/l, 0.09 to 1.1 103 MPN/ml, 9 to 210 MPN/g and 1.5 to 2.1 MPN/g, respectively. In winter, all samples except mussels contained V. parahaemolyticus, but at very low concentrations. Pathogenic (tdh- or trh2-positive) V. parahaemolyticus were present in water, sediment and shellfish samples collected from these lagoons. The number of V. vulnificus in water, sediment and shellfish samples ranged from 1 to 1.1 103 MPN/l, 0.07 to 110 MPN/ml and 0.04 to 15 MPN/g, respectively, during summer. V. vulnificus was not detected during winter. V. cholerae was rarely detected in water and sediment during summer. In summary, results of this study highlight the finding that the three human pathogenic Vibrio spp. are present in the lagoons and constitute a potential public health hazard. PMID:23770313

  6. The ecology of Vibrio vulnificus, Vibrio cholerae, and Vibrio parahaemolyticus in North Carolina estuaries.

    PubMed

    Blackwell, Karen Dyer; Oliver, James D

    2008-04-01

    While numerous studies have characterized the distribution and/or ecology of various pathogenic Vibrio spp., here we have simultaneously examined several estuarine sites for Vibrio vulnificus, V. cholerae, and V. parahaemolyticus. For a one year period, waters and sediment were monitored for the presence of these three pathogens at six different sites on the east coast of North Carolina in the United States. All three pathogens, identified using colony hybridization and PCR methods, occurred in these estuarine environments, although V. cholerae occurred only infrequently and at very low levels. Seventeen chemical, physical, and biological parameters were investigated, including salinity, water temperature, turbidity, dissolved oxygen, levels of various inorganic nutrients and dissolved organic carbon, as well as total vibrios, total coliforms, and E. coli. We found each of the Vibrio spp. in water and sediment to correlate to several of these environmental measurements, with water temperature and total Vibrio levels correlating highly (P<0.0001) with occurrence of the three pathogens. Thus, these two parameters may represent simple assays for characterizing the potential public health hazard of estuarine waters. PMID:18545963

  7. Polyphasic Taxonomy of the Genus Vibrio: Numerical Taxonomy of Vibrio cholerae, Vibrio parahaemolyticus, and Related Vibrio Species

    PubMed Central

    Colwell, R. R.

    1970-01-01

    A set of 86 bacterial cultures, including 30 strains of Vibrio cholerae, 35 strains of V. parahaemolyticus, and 21 representative strains of Pseudomonas, Spirillum, Achromobacter, Arthrobacter, and marine Vibrio species were tested for a total of 200 characteristics. Morphological, physiological, and biochemical characteristics were included in the analysis. Overall deoxyribonucleic acid (DNA) base compositions and ultrastructure, under the electron microscope, were also examined. The taxonomic data were analyzed by computer by using numerical taxonomy programs designed to sort and cluster strains related phenetically. The V. cholerae strains formed an homogeneous cluster, sharing overall S values of ?75%. Two strains, V. cholerae NCTC 30 and NCTC 8042, did not fall into the V. cholerae species group when tested by the hypothetical median organism calculation. No separation of classic V. cholerae, El Tor vibrios, and nonagglutinable vibrios was observed. These all fell into a single, relatively homogeneous, V. cholerae species cluster. V. parahaemolyticus strains, excepting 5144, 5146, and 5162, designated members of the species V. alginolyticus, clustered at S ?80%. Characteristics uniformly present in all the Vibrio species examined are given, as are also characteristics and frequency of occurrence for V. cholerae and V. parahaemolyticus. The clusters formed in the numerical taxonomy analyses revealed similar overall DNA base compositions, with the range for the Vibrio species of 40 to 48% guanine plus cytosine. Generic level of relationship of V. cholerae and V. parahaemolyticus is considered dubious. Intra- and intergroup relationships obtained from the numerical taxonomy studies showed highly significant correlation with DNA/DNA reassociation data. Images PMID:5473901

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

    PubMed

    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

  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. 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.

  11. 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

  12. 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...

  13. 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

  14. Chemoattraction of Vibrio fischeri to Serine, Nucleosides, and N-Acetylneuraminic Acid, a Component of Squid Light-Organ Mucus

    PubMed Central

    DeLoney-Marino, Cindy R.; Wolfe, Alan J.; Visick, Karen L.

    2003-01-01

    Newlyhatched juveniles of the Hawaiian squid Euprymna scolopes rapidly become colonized by the bioluminescent marine bacterium Vibrio fischeri. Motility is required to establish the symbiotic colonization, but the role of chemotaxis is unknown. In this study we analyzed chemotaxis of V. fischeri to a number of potential attractants. The bacterium migrated toward serine and most sugars tested. V. fischeri also exhibited the unusual ability to migrate to nucleosides and nucleotides as well as to N-acetylneuraminic acid, a component of squid mucus. PMID:14660408

  15. Shedding light on bioluminescence regulation in Vibrio fischeri.

    PubMed

    Miyashiro, Tim; Ruby, Edward G

    2012-06-01

    The bioluminescence emitted by the marine bacterium Vibrio fischeri is a particularly striking result of individual microbial cells co-ordinating a group behaviour. The genes responsible for light production are principally regulated by the LuxR-LuxI quorum-sensing system. In addition to LuxR-LuxI, numerous other genetic elements and environmental conditions control bioluminescence production. Efforts to mathematically model the LuxR-LuxI system are providing insight into the dynamics of this autoinduction behaviour. The Hawaiian squid Euprymna scolopes forms a natural symbiosis with V. fischeri, and utilizes the symbiont-derived bioluminescence for certain nocturnal behaviours, such as counterillumination. Recent work suggests that the tissue with which V. fischeri associates not only can detect bioluminescence but may also use this light to monitor the V. fischeri population. PMID:22500943

  16. 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

  17. Occurrence of Vibrio parahaemolyticus, Vibrio cholerae, and Vibrio vulnificus in the Aquacultural Environments of Taiwan.

    PubMed

    Tey, Yao Hsien; Jong, Koa-Jen; Fen, Shin-Yuan; Wong, Hin-Chung

    2015-05-01

    The occurrence of Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio cholerae in a total of 72 samples from six aquaculture ponds for groupers, milk fish, and tilapia in southern Taiwan was examined by the membrane filtration and colony hybridization method. The halophilic V. parahaemolyticus was only recovered in seawater ponds, with a high isolation frequency of 86.1% and a mean density of 2.6 log CFU/g. V. cholerae was found in both the seawater and freshwater ponds but preferentially in freshwater ponds, with a frequency of 72.2% and a mean density of 1.65 log CFU/g. V. vulnificus was identified mainly in seawater ponds, with an isolation frequency of 27.8%. The density of V. parahaemolyticus in seawater ponds was positively related to water temperature (Pearson correlation coefficient, r = 0.555) and negatively related to salinity (r = 2 0.333). The density of V. cholerae in all six ponds was positively related to water temperature (r = 0.342) and negatively related to salinity (r = 2 0.432). Two putatively pathogenic tdh(+) V. parahaemolyticus isolates (1.4% of the samples) and no ctx(+) V. cholerae isolates were identified. The experimental results may facilitate assessments of the risk posed by these pathogenic Vibrio species in Taiwan, where aquaculture provides a large part of the seafood supply. PMID:25951392

  18. Lateral Flagellar Gene System of Vibrio parahaemolyticus

    PubMed Central

    Stewart, Bonnie J.; McCarter, Linda L.

    2003-01-01

    Vibrio parahaemolyticus possesses dual flagellar systems adapted for movement under different circumstances. A single polar flagellum propels the bacterium in liquid (i.e., swimming) with a motor that is powered by the sodium motive force. Multiple proton-driven lateral flagella enable translocation over surfaces (i.e., swarming). The polar flagellum is produced continuously, while production of lateral flagella is induced when the organism is grown on surfaces. This work describes the isolation of mutants with insertions in the structural and regulatory laf genes. A Tn5-based lux transcriptional reporter transposon was constructed and used for mutagenesis and subsequent transcriptional analysis of the laf regulon. Twenty-nine independent insertions were distributed within 16 laf genes. DNA sequence analysis identified 38 laf genes in two loci. Among the mutants isolated, 11 contained surface-induced lux fusions. A hierarchy of laf gene expression was established following characterization of the laf::lux transcriptional fusion strains and by mutational and primer extension analyses of the laf regulon. The laf system is like many enteric systems in that it is a proton-driven, peritrichous flagellar system; however, laf regulation was different from the Salmonella-Escherichia coli paradigm. There is no apparent flhDC counterpart that encodes master regulators known to control flagellar biosynthesis and swarming in many enteric bacteria. A potential ?54-dependent regulator, LafK, was demonstrated to control expression of early genes, and a lateral-specific ?28 factor controls late flagellar gene expression. Another notable feature was the discovery of a gene encoding a MotY-like product, which previously had been associated only with the architecture of sodium-type polar flagellar motors. PMID:12867460

  19. Ecology of Vibrio parahaemolyticus in Chesapeake Bay

    PubMed Central

    Kaneko, Tatsuo; Colwell, Rita R.

    1973-01-01

    A study of the ecology of Vibrio parahaemolyticus and related vibrios in the Rhode River area of Chesapeake Bay was carried out over the period December 1970 through August 1971. The incidence of V. parahaemolyticus and related vibrios was found to be correlated with water temperature. The vibrios could not be detected in the water column during the winter months, although they were present in sediment. From late spring to early summer, when water temperatures were 14 ± 1 C, vibrios over-wintering in sediment were released from the bottom communities and attached to zooplankton, proliferating as the temperature rose. The number of vibrios in and on plankton was reflected in the water column bacterial population densities at water temperatures of ca. 19 C. Thus, temperature of the water column in the range of 14 to 19 C was found to be critical in the annual cycle of the vibrios. Interaction between sediment, water, and zooplankton was found to be essential in the natural estuarine ecosystem. Bacterial counts of zooplankton were found to be temperature dependent. The bacterial population associated with zooplankton was found to be predominantly on external surfaces and was specific, differing from that of the sediment. Vibrio spp. and related organisms comprised the total bacterial population associated with zooplankton in summer months. The ecological role of Vibrio spp., including V. parahaemolyticus, was found to be significant, with respect to their property of chitin digestion and in relation to the population dynamics of zooplankton in Chesapeake Bay. PMID:4567138

  20. 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

  1. The Biology of Vibrio vulnificus.

    PubMed

    Oliver, James D

    2015-06-01

    Vibrio vulnificus, carrying a 50% fatality rate, is the most deadly of the foodborne pathogens. It occurs in estuarine and coastal waters and it is found in especially high numbers in oysters and other molluscan shellfish. The biology of V. vulnificus, including its ecology, pathogenesis, and molecular genetics, has been described in numerous reviews. This article provides a brief summary of some of the key aspects of this important human pathogen, including information on biotypes and genotypes, virulence factors, risk factor requirements and the role of iron in disease, association with oysters, geographic distribution, importance of salinity and water temperature, increasing incidence associated with global warming. This article includes some of our findings as presented at the "Vibrios in the Environment 2010" conference held in Biloxi, MS. PMID:26185084

  2. [Vibrio infections from food and sea water. Introducing the "VibrioNet"].

    PubMed

    Alter, T; Appel, B; Bartelt, E; Dieckmann, R; Eichhorn, C; Erler, R; Frank, C; Gerdts, G; Gunzer, F; Hhn, S; Neifer, J; Oberheitmann, B; Strauch, E

    2011-11-01

    Vibrio is a genus of bacteria present in surface and coastal waters as well as in marine organisms worldwide. In many countries, pathogenic Vibrio species are a main cause of bacterial diarrhea, which may result from comsumption of contaminated seafood and fish products or from drinking contaminated water. Vibrio infections may also gain in importance in our regions due to global warming and the increase in the world trade of seafood. The research network "VibrioNet" studies pathogenic Vibrios in the marine environment and in seafood consumed by humans as a potential, new emerging zoonotic agent. An assessment of the risk arising from pathogenic non-cholera-vibrios in central Europe is the target of a multidisciplinary research effort. The research network will be strengthened by cooperations with international partners from countries in which Vibrio infections play a major role (Bangladesh, Chile, India, Thailand, and Vietnam). PMID:22015796

  3. Effect of the addition of four potential probiotic strains on the survival of pacific white shrimp (Litopenaeus vannamei) following immersion challenge with Vibrio parahaemolyticus.

    PubMed

    Balczar, Jos Luis; Rojas-Luna, Tyrone; Cunningham, David P

    2007-10-01

    Four bacterial strains isolated from the gastrointestinal tract of adult shrimp Litopenaeus vannamei, Vibrio alginolyticus UTM 102, Bacillus subtilis UTM 126, Roseobacter gallaeciensis SLV03, and Pseudomonas aestumarina SLV22, were evaluated for potential use as probiotics for shrimp. In vitro studies demonstrated antagonism against the shrimp-pathogenic bacterium, Vibrio parahaemolyticus PS-017. Feeding shrimp with diets containing the potential probiotics showed the best feed conversion ratio in comparison with the control groups. After feeding with the potential probiotics for 28 days, challenge by immersion indicated effectiveness at reducing disease caused by V. parahaemolyticus in shrimp. PMID:17544437

  4. Properties of proteolytic toxin of Vibrio anguilolarum from diseased flounder

    NASA Astrophysics Data System (ADS)

    Mo, Zhao-Lan; Chen, Shi-Yong; Zhang, Pei-Jun

    2002-12-01

    Extracellular products (ECP) produced by Vibrio anguillarum strain M3 originally isolated from diseased flounder ( Paralichthys olivaceus) were prepared. ECP of M3 showed gelatinase, casinase, amylase and haemolytic activity on agarose plates. High protease activity against azocasin was detected. Bacterium M2 showed highest growth and protease activity at 25C. The protease present in ECP showed maximal activity at pH 8 and 55C; was completely inactivated by application of 80C heat for 30 min; was completely inhibited by EDTA and HgCl2, and was partially inhibited by PMSF, SDS, MnCl2 and iodoacetic acid; but not inhibited by CaCl2 and MgCl2. The ECP was toxic to flounder fish at LD50 values of 3.1 ?g protein/g body weight. The addition of HgCl2 and application of heat at 50C decreased the lethal toxicity of ECP. When heated at 100C, ECP lethality to flounder was completely inhibited. After intramuscular injection of ECP into flounder, it showed evident histopathological changes including necrosis of muscle, extensive deposition of haemosiderin in the spleen, dilated blood vessels congested with numerious lymphocytes in the liver. These results showed that ECP protease was a lethal factor produced by the bacterium V. anguillarum M3.

  5. Zebrafish as a model for Vibrio parahaemolyticus virulence.

    PubMed

    Paranjpye, Rohinee N; Myers, Mark S; Yount, Evan C; Thompson, Jessica L

    2013-12-01

    Vibrio parahaemolyticus is a Gram-negative, naturally occurring marine bacterium. Subpopulations of strains belonging to this species cause an acute self-limiting gastroenteritis in humans and, less commonly, wound infections. In vivo models to differentiate avirulent and virulent strains and evaluate the pathogenic potential of strains of this species have been largely focused on the presence of known virulence factors such as the thermostable direct haemolysin (TDH), the TDH-related haemolysin (TRH) or the contributions of the type 3 secretion systems. However, virulence is likely to be multifactorial, and additional, yet to be identified factors probably contribute to virulence in this bacterium. In this study, we investigated an adult zebrafish model to assess the overall virulence of V. parahaemolyticus strains. The model could detect differences in the virulence potential of strains when animals were challenged intraperitoneally, based on survival time. Differences in survival were noted irrespective of the source of isolation of the strain (environmental or clinical) and regardless of the presence or absence of the known virulence factors TDH and TRH, suggesting the influence of additional virulence factors. The model was also effective in comparing differences in virulence between the wild-type V. parahaemolyticus strain RIMD2210633 and isogenic pilin mutants ?pilA and ?mshA, a double mutant ?pilA?:??mshA, as well as a putative chitin-binding protein mutant, ?gbpA. PMID:24056807

  6. Characterization of low salinity stress in Vibrio parahaemolyticus.

    PubMed

    Huang, Wei Shen; Wong, Hin-Chung

    2012-02-01

    Vibrio parahaemolyticus is a marine foodborne pathogenic bacterium commonly found in seawater or seafood. This bacterium often encounters low salinity stress when the contaminated seafood is washed with fresh water during food processing. This study was conducted to investigate the response of exponential- and stationary-phase cells of V. parahaemolyticus ST550 to lethal or sublethal low salinity. Tolerance to lethal low salinity (0.25% NaCl) was enhanced in V. parahaemolyticus cells in the exponential phase by previous adaptation in sublethal low salinity (0.6% NaCl). Low salinity-adapted cells in the exponential phase were also cross-protected against the challenge of lethal low pH, indifferent to heat, and sensitized to bile, acetic acid, and lactic acid stress. The adapted cells in the stationary phase were significantly protected against heat treatment at 44C for 10 and 15 min, sensitized to bile and acetic acid treatment, and indifferent to low pH and lactic acid. PMID:22289582

  7. Phage therapy treatment of the coral pathogen Vibrio coralliilyticus.

    PubMed

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

    2013-02-01

    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

  8. Essential role for estrogen in protection against Vibrio vulnificus-induced endotoxic shock.

    PubMed

    Merkel, S M; Alexander, S; Zufall, E; Oliver, J D; Huet-Hudson, Y M

    2001-10-01

    Little is known about the underlying mechanisms that result in a sexually dimorphic response to Vibrio vulnificus endotoxic shock. V. vulnificus is a gram-negative bacterium, considered one of the most invasive and rapidly fatal human pathogens known. However, 85% of individuals that develop endotoxic shock from V. vulnificus are males. Using the rat, we have developed a model for V. vulnificus endotoxic shock that mimics the sexually dimorphic response in humans. Gonadectomy in females results in increased mortality, and estrogen replacement results in decreased mortality in both gonadectomized males and females. These results demonstrate that estrogen is providing protection against V. vulnificus lipopolysaccharide-induced endotoxic shock. PMID:11553550

  9. 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.

  10. 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

  11. Subversion of the cytoskeleton by intracellular bacteria: lessons from Listeria, Salmonella and Vibrio.

    PubMed

    de Souza Santos, Marcela; Orth, Kim

    2015-02-01

    Entry into host cells and intracellular persistence by invasive bacteria are tightly coupled to the ability of the bacterium to disrupt the eukaryotic cytoskeletal machinery. Herein we review the main strategies used by three intracellular pathogens to harness key modulators of the cytoskeleton. Two of these bacteria, namely Listeria monocytogenes and Salmonella enterica serovar Typhimurium, exhibit quite distinct intracellular lifestyles and therefore provide a comprehensive panel for the understanding of the intricate bacteria-cytoskeleton interplay during infections. The emerging intracellular pathogen Vibrio parahaemolyticus is depicted as a developing model for the uncovering of novel mechanisms used to hijack the cytoskeleton. PMID:25440316

  12. Permanent draft genome sequence of Vibrio tubiashii strain NCIMB 1337 (ATCC19106).

    SciTech Connect

    Temperton, B.; Thomas, S.; Tait, K.; Parry, H.; Emery, M.; Allen, M.; Quinn, J.; McGrath, J.; Gilbert, J.

    2011-01-01

    Vibrio tubiashii NCIMB 1337 is a major and increasingly prevalent pathogen of bivalve mollusks, and shares a close phylogenetic relationship with both V. orientalis and V. coralliilyticus. It is a Gram-negative, curved rod-shaped bacterium, originally isolated from a moribund juvenile oyster, and is both oxidase and catalase positive. It is capable of growth under both aerobic and anaerobic conditions. Here we describe the features of this organism, together with the draft genome and annotation. The genome is 5,353,266 bp long, consisting of two chromosomes, and contains 4,864 protein-coding and 86 RNA genes.

  13. Multiplex PCR assays for the detection of Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio cholerae with an internal amplification control.

    PubMed

    Wei, Shuang; Zhao, Hui; Xian, Yuyin; Hussain, Malik A; Wu, Xiyang

    2014-06-01

    A multiplex polymerase chain reaction (PCR) assay that can simultaneously detect 4 major Vibrio spp., Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio cholerae, in the presence of an internal amplification control (IAC) was developed. Species-specific PCR primers were designed based on the gyrB gene for V. alginolyticus, the collagenase gene for V. parahaemolyticus, the vvhA gene for V. vulnificus, and the ompW gene for V. cholerae. Additionally, an IAC primer pair was designed in conserved regions of the bacterial 16S rRNA gene that is used to indicate false-negative results. A multiplex PCR method was developed after optimization of the reaction conditions. The specificity of the PCR was validated by using 83 Vibrio strains and 10 other non-Vibrio bacterial species. The detection limit of the PCR was 10 CFU per tube for V. alginolyticus, V. parahaemolyticus, V. vulnificus, and 10(5) CFU per tube for V. cholerae in mixed conditions. This method was used to identify 69 suspicious Vibrio isolates, and the results were consistent with physiological and biochemical tests. This multiplex PCR method proved to be rapid, sensitive, and specific. The existence of IAC could successfully eliminate false-negative results for the detection of V. alginolyticus, V. parahaemolyticus, V. vulnificus, and V. cholerae. PMID:24731836

  14. Characterization of htrB and msbB mutants of the light organ symbiont Vibrio fischeri.

    PubMed

    Adin, Dawn M; Phillips, Nancy J; Gibson, Bradford W; Apicella, Michael A; Ruby, Edward G; McFall-Ngai, Margaret J; Hall, Daniel B; Stabb, Eric V

    2008-02-01

    Bacterial lipid A is an important mediator of bacterium-host interactions, and secondary acylations added by HtrB and MsbB can be critical for colonization and virulence in pathogenic infections. In contrast, Vibrio fischeri lipid A stimulates normal developmental processes in this bacterium's mutualistic host, Euprymna scolopes, although the importance of lipid A structure in this symbiosis is unknown. To further examine V. fischeri lipid A and its symbiotic function, we identified two paralogs of htrB (designated htrB1 and htrB2) and an msbB gene in V. fischeri ES114 and demonstrated that these genes encode lipid A secondary acyltransferases. htrB2 and msbB are found on the Vibrio "housekeeping" chromosome 1 and are conserved in other Vibrio species. Mutations in htrB2 and msbB did not impair symbiotic colonization but resulted in phenotypic alterations in culture, including reduced motility and increased luminescence. These mutations also affected sensitivity to sodium dodecyl sulfate, kanamycin, and polymyxin, consistent with changes in membrane permeability. Conversely, htrB1 is located on the smaller, more variable vibrio chromosome 2, and an htrB1 mutant was wild-type-like in culture but appeared attenuated in initiating the symbiosis and was outcompeted 2.7-fold during colonization when mixed with the parent. These data suggest that htrB2 and msbB play conserved general roles in vibrio biology, whereas htrB1 plays a more symbiosis-specific role in V. fischeri. PMID:18065606

  15. An intracellular replication niche for Vibrio cholerae in the amoeba Acanthamoeba castellanii.

    PubMed

    Van der Henst, Charles; Scrignari, Tiziana; Maclachlan, Catherine; Blokesch, Melanie

    2016-04-01

    Vibrio cholerae is a human pathogen and the causative agent of cholera. The persistence of this bacterium in aquatic environments is a key epidemiological concern, as cholera is transmitted through contaminated water. Predatory protists, such as amoebae, are major regulators of bacterial populations in such environments. Therefore, we investigated the interaction between V. cholerae and the amoeba Acanthamoeba castellanii at the single-cell level. We observed that V. cholerae can resist intracellular killing. The non-digested bacteria were either released or, alternatively, established a replication niche within the contractile vacuole of A. castellanii. V. cholerae was maintained within this compartment even upon encystment. The pathogen ultimately returned to its aquatic habitat through lysis of A. castellanii, a process that was dependent on the production of extracellular polysaccharide by the pathogen. This study reinforces the concept that V. cholerae is a facultative intracellular bacterium and describes a new host-pathogen interaction. PMID:26394005

  16. Enhancement of UV light sensitivity of a Vibrio parahaemolyticus O3:K6 pandemic strain due to natural lysogenization by a telomeric phage.

    PubMed

    Zabala, Beatriz; Garca, Katherine; Espejo, Romilio T

    2009-03-01

    The Vibrio parahaemolyticus O3:K6 pandemic clonal strain was first observed in southern Chile in 2004 and has since caused approximately 8,000 seafood-related diarrhea cases in this region. The massive proliferation of the original clonal population offers a unique opportunity to study the evolution of a bacterial pathogen in its natural environment by detection and characterization of emerging bacterial variants. Here, we describe a group of pandemic variants characterized by the presence of a 42-kb extrachromosomal DNA that can be recovered by alkaline extraction. Upon treatment with mitomycin C, these variants lyse with production of a myovirus containing DNA of equal size to the plasmid but which cannot be recovered by alkaline extraction. Plasmid and phage DNAs show similar restriction patterns corresponding to enzyme sites in a circular permutation. Sequenced regions showed 81 to 99% nucleotide similarity to bacteriophage VHML of Vibrio harveyi. Altogether these observations indicate that the 42-kb plasmid corresponds to a prophage, consisting of a linear DNA with terminal hairpins of a telomeric temperate phage with a linear genome. Bacteria containing the prophage were 7 to 15 times more sensitive to UV radiation, likely due to phage induction by UV irradiation as plasmid curing restored the original sensitivity. The enhanced UV sensitivity could have a significant role in reducing the survival and propagation capability of the V. parahaemolyticus pandemic strain in the ocean. PMID:19151181

  17. Mesenteric Panniculitis Associated With Vibrio cholerae Infection.

    PubMed

    Roginsky, Grigory; Mazulis, Andrew; Ecanow, Jacob S; Ehrenpreis, Eli D

    2015-10-01

    We report the first case of acute Vibrio cholerae infection with computed tomography (CT) changes consistent with mesenteric panniculitis (MP). A 78-year-old Indian man returned from overseas travel with progressively severe nausea, vomiting, abdominal pain, and watery diarrhea. His stool tested positive twice for Vibrio cholerae. CT revealed prominent lymph nodes and a hazy mesentery consistent with MP. Antibiotic treatment resulted in complete resolution of MP on follow-up CT 8 months later. In the setting of Vibrio cholerae infection, the CT finding of MP appears to be the result of a immunologically mediated reactive inflammatory disorder of the mesentery. PMID:26504876

  18. Mesenteric Panniculitis Associated With Vibrio cholerae Infection

    PubMed Central

    Roginsky, Grigory; Mazulis, Andrew; Ecanow, Jacob S.

    2015-01-01

    We report the first case of acute Vibrio cholerae infection with computed tomography (CT) changes consistent with mesenteric panniculitis (MP). A 78-year-old Indian man returned from overseas travel with progressively severe nausea, vomiting, abdominal pain, and watery diarrhea. His stool tested positive twice for Vibrio cholerae. CT revealed prominent lymph nodes and a hazy mesentery consistent with MP. Antibiotic treatment resulted in complete resolution of MP on follow-up CT 8 months later. In the setting of Vibrio cholerae infection, the CT finding of MP appears to be the result of a immunologically mediated reactive inflammatory disorder of the mesentery. PMID:26504876

  19. Gimme shelter: how Vibrio fischeri successfully navigates an animal's multiple environments.

    PubMed

    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

  20. 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

  1. 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

  2. Vibrio parahaemolyticus in Brazilian coastal waters.

    PubMed

    Franca, S M; Gibbs, D L; Samuels, P; Johnson, W D

    1980-08-01

    Vibrio parahaemolyticus has been increasingly recognized as an important cause of acute diarrheal illness in Asia, Europe, Africa, Australia, and North America. We investigated whether this pathogen was also present in Brazil and found that 10% of the fish samples studied were contaminated with this halophilic vibrio. Positive cultures were obtained in three of 64 fish (5%) and in seven of 36 shell fish (19%). PMID:7190196

  3. Resistance to Antimicrobial Peptides in Vibrios

    PubMed Central

    Destoumieux-Garzón, Delphine; Duperthuy, Marylise; Vanhove, Audrey Sophie; Schmitt, Paulina; Wai, Sun Nyunt

    2014-01-01

    Vibrios are associated with a broad diversity of hosts that produce antimicrobial peptides (AMPs) as part of their defense against microbial infections. In particular, vibrios colonize epithelia, which function as protective barriers and express AMPs as a first line of chemical defense against pathogens. Recent studies have shown they can also colonize phagocytes, key components of the animal immune system. Phagocytes infiltrate infected tissues and use AMPs to kill the phagocytosed microorganisms intracellularly, or deliver their antimicrobial content extracellularly to circumvent tissue infection. We review here the mechanisms by which vibrios have evolved the capacity to evade or resist the potent antimicrobial defenses of the immune cells or tissues they colonize. Among their strategies to resist killing by AMPs, primarily vibrios use membrane remodeling mechanisms. In particular, some highly resistant strains substitute hexaacylated Lipid A with a diglycine residue to reduce their negative surface charge, thereby lowering their electrostatic interactions with cationic AMPs. As a response to envelope stress, which can be induced by membrane-active agents including AMPs, vibrios also release outer membrane vesicles to create a protective membranous shield that traps extracellular AMPs and prevents interaction of the peptides with their own membranes. Finally, once AMPs have breached the bacterial membrane barriers, vibrios use RND efflux pumps, similar to those of other species, to transport AMPs out of their cytoplasmic space.

  4. Hatchery mortalities of larval oysters caused by Vibrio tubiashii and Vibrio coralliilyticus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hatchery production of bivalve shellfish has been hampered by the occasional presence of opportunistic pathogens, particularly Vibrio coralliilyticus and Vibrio tubiashii. The present study reports the results of several avenues of research to better define these pathogens and the roles they play i...

  5. Occurrence of virulence genes among Vibrio cholerae and Vibrio parahaemolyticus strains from treated wastewaters.

    PubMed

    Khouadja, Sadok; Suffredini, Elisabetta; Baccouche, Besma; Croci, Luciana; Bakhrouf, Amina

    2014-10-01

    Pathogenic Vibrio species are an important cause of foodborne illnesses. The aim of this study was to describe the occurrence of potentially pathogenic Vibrio species in the final effluents of a wastewater treatment plant and the risk that they may pose to public health. During the 1-year monitoring, a total of 43 Vibrio strains were isolated: 23 Vibrio alginolyticus, 1 Vibrio cholerae, 4 Vibrio vulnificus, and 15 Vibrio parahaemolyticus. The PCR investigation of V. parahaemolyticus and V. cholerae virulence genes (tlh, trh, tdh, toxR, toxS, toxRS, toxT, zot, ctxAB, tcp, ace, vpi, nanH) revealed the presence of some of these genes in a significant number of strains. Intraspecies variability and genetic relationships among the environmental isolates were analyzed by random amplified polymorphic DNA-PCR (RAPD-PCR). We report the results of the first isolation and characterization of an environmental V. cholerae non-O1 non-O139 and of a toxigenic V. parahaemolyticus strain in Tunisia. We suggest that non-pathogenic Vibrio might represent a marine reservoir of virulence genes that can be transmitted between strains by horizontal transfer. PMID:25023745

  6. Non-O1, non-O139 Vibrio cholerae sepsis in a patient with nephrotic syndrome.

    PubMed

    George, N; Fredrick, F; Mohapatra, A; Veeraraghavan, B; Kakde, S T; Valson, A T; Basu, G

    2013-09-01

    Non-O1, non-O139 Vibrio cholerae is an encapsulated bacterium, ubiquitous in the marine environment and generally considered to be non-pathogenic. However, it is known to cause diarrheal illness, wound infection, and bacteremia in immunocompromised hosts. Here we have describe non-O1, non-O139 V. cholerae sepsis in a patient with nephrotic syndrome following exposure to sea-water. Interestingly, the exposure occurred remotely 4 months prior to the onset of nephrotic syndrome. The occurrence of florid sepsis after a prolonged interval from the time of exposure is peculiar and raises the possibility of an association between occult Vibrio sepsis and nephrotic syndrome. PMID:24049279

  7. Rapid proliferation of Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio cholerae during freshwater flash floods in French Mediterranean coastal lagoons.

    PubMed

    Esteves, Kevin; Hervio-Heath, Dominique; Mosser, Thomas; Rodier, Claire; Tournoud, Marie-George; Jumas-Bilak, Estelle; Colwell, Rita R; Monfort, Patrick

    2015-11-01

    Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio cholerae of the non-O1/non-O139 serotype are present in coastal lagoons of southern France. In these Mediterranean regions, the rivers have long low-flow periods followed by short-duration or flash floods during and after heavy intense rainstorms, particularly at the end of the summer and in autumn. These floods bring large volumes of freshwater into the lagoons, reducing their salinity. Water temperatures recorded during sampling (15 to 24°C) were favorable for the presence and multiplication of vibrios. In autumn 2011, before heavy rainfalls and flash floods, salinities ranged from 31.4 to 36.1‰ and concentrations of V. parahaemolyticus, V. vulnificus, and V. cholerae varied from 0 to 1.5 × 10(3) most probable number (MPN)/liter, 0.7 to 2.1 × 10(3) MPN/liter, and 0 to 93 MPN/liter, respectively. Following heavy rainstorms that generated severe flash flooding and heavy discharge of freshwater, salinity decreased, reaching 2.2 to 16.4‰ within 15 days, depending on the site, with a concomitant increase in Vibrio concentration to ca. 10(4) MPN/liter. The highest concentrations were reached with salinities between 10 and 20‰ for V. parahaemolyticus, 10 and 15‰ for V. vulnificus, and 5 and 12‰ for V. cholerae. Thus, an abrupt decrease in salinity caused by heavy rainfall and major flooding favored growth of human-pathogenic Vibrio spp. and their proliferation in the Languedocian lagoons. Based on these results, it is recommended that temperature and salinity monitoring be done to predict the presence of these Vibrio spp. in shellfish-harvesting areas of the lagoons. PMID:26319881

  8. Single Bacterium Detection Using Sers

    NASA Astrophysics Data System (ADS)

    Gonchukov, S. A.; Baikova, T. V.; Alushin, M. V.; Svistunova, T. S.; Minaeva, S. A.; Ionin, A. A.; Kudryashov, S. I.; Saraeva, I. N.; Zayarny, D. A.

    2016-02-01

    This work is devoted to the study of a single Staphylococcus aureus bacterium detection using surface-enhanced Raman spectroscopy (SERS) and resonant Raman spectroscopy (RS). It was shown that SERS allows increasing sensitivity of predominantly low frequency lines connected with the vibrations of Amide, Proteins and DNA. At the same time the lines of carotenoids inherent to this kind of bacterium are well-detected due to the resonance Raman scattering mechanism. The reproducibility and stability of Raman spectra strongly depend on the characteristics of nanostructured substrate, and molecular structure and size of the tested biological object.

  9. 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...

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

    PubMed

    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

  11. 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

  12. Effects of Global Warming on Vibrio Ecology.

    PubMed

    Vezzulli, Luigi; Pezzati, Elisabetta; Brettar, Ingrid; Höfle, Manfred; Pruzzo, Carla

    2015-06-01

    Vibrio-related infections are increasing worldwide both in humans and aquatic animals. Rise in global sea surface temperature (SST), which is approximately 1 °C higher now than 140 years ago and is one of the primary physical impacts of global warming, has been linked to such increases. In this chapter, major known effects of increasing SST on the biology and ecology of vibrios are described. They include the effects on bacterial growth rate, both in the field and in laboratory, culturability, expression of pathogenicity traits, and interactions with aquatic organisms and abiotic surfaces. Special emphasis is given to the effect of ocean warming on Vibrio interactions with zooplankters, which represent one of the most important aquatic reservoirs for these bacteria. The reported findings highlight the biocomplexity of the interactions between vibrios and their natural environment in a climate change scenario, posing the need for interdisciplinary studies to properly understand the connection between ocean warming and persistence and spread of vibrios in sea waters and the epidemiology of the diseases they cause. PMID:26185070

  13. Vibrio parahaemolyticus type IV pili mediate interactions with diatom-derived chitin and point to an unexplored mechanism of environmental persistence.

    PubMed

    Frischkorn, Kyle R; Stojanovski, Asta; Paranjpye, Rohinee

    2013-05-01

    Vibrio parahaemolyticus is a naturally occurring bacterium common in coastal waters where it concentrates in shellfish through filter feeding. The bacterium is a human pathogen and the leading cause of seafood-borne gastroenteritis. Presently there is little information regarding mechanisms of environmental persistence of V.parahaemolyticus or an accurate early warning system for outbreak prediction. Vibrios have been shown to adhere to several substrates in the environment, including chitin, one of the most abundant polymers in the ocean. Diatoms are abundant in estuarine waters and some species produce chitin as a component of the silica cell wall or as extracellular fibrils. We examined the role of specific surface structures on the bacterium, the type IV pilins PilA and MshA, in adherence to diatom-derived chitin. Biofilm formation and adherence of V.parahaemolyticus to chitin is mediated by the ability of the bacterium to express functional type IV pili. The amount of adherence to diatom-derived chitin is controlled by increased chitin production that occurs in later stages of diatom growth. The data presented here suggest late-stage diatom blooms may harbour high concentrations of V.parahaemolyticus and could serve as the foundation for a more accurate early warning system for outbreaks of this human pathogen. PMID:23441888

  14. Cholera and other vibrio-associated diarrhoeas.

    PubMed

    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

  15. 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...

  16. Antibiotic-Resistant Vibrios in Farmed Shrimp

    PubMed Central

    Albuquerque Costa, Renata; Arajo, Rayza Lima; Souza, Oscarina Viana; Vieira, Regine Helena Silva dos Fernandes

    2015-01-01

    Antimicrobial susceptibility pattern was determined in 100 strains of Vibrio isolated from the Litopenaeus vannamei shrimp and identified phenotypically. A high antibiotic-resistance index (75%) was observed, with the following phenotypic profiles: monoresistance (n = 42), cross-resistance to ?-lactams (n = 20) and multiple resistance (n = 13). Plasmid resistance was characterized for penicillin (n = 11), penicillin + ampicillin (n = 1), penicillin + aztreonam (n = 1), and ampicillin (n = 1). Resistance to antimicrobial drugs by the other strains (n = 86) was possibly mediated by chromosomal genes. The findings of this study support the conclusion that the cultured shrimps can be vehicles of vibrios resistant to ?-lactam and tetracycline. PMID:25918714

  17. Vibrio parahaemolyticus, enterotoxigenic Escherichia coli, enterohemorrhagic Escherichia coli and Vibrio cholerae

    PubMed Central

    TAKEDA, Yoshifumi

    2011-01-01

    This review highlighted the following: (i) pathogenic mechanism of the thermostable direct hemolysin produced by Vibrio parahaemolyticus, especially on its cardiotoxicity, (ii) heat-labile and heat-stable enterotoxins produced by enterotoxigenic Escherichia coli, especially structureactivity relationship of heat-stable enterotoxin, (iii) RNA N-glycosidase activity of Vero toxins (VT1 and VT2) produced by enterohemorrhagic Escherichia coli O157:H7, (iv) discovery of Vibrio cholerae O139, (v) isolation of new variant of Vibrio cholerae O1 El Tor that carries classical ctxB, and production of high concentration of cholera toxin by these strains, and (vi) conversion of viable but nonculturable (VBNC) Vibrio cholerae to culturable state by co-culture with eukaryotic cells. PMID:21233598

  18. Occurrence of Vibrio parahaemolyticus and Vibrio alginolyticus in the German Bight over a seasonal cycle.

    PubMed

    Oberbeckmann, Sonja; Wichels, Antje; Wiltshire, Karen H; Gerdts, Gunnar

    2011-08-01

    Bacteria of the genus Vibrio are an important component of marine ecosystems worldwide. The genus harbors several human pathogens, for instance the species Vibrio parahaemolyticus, a main cause for foodborne gastroenteritis in Asia and the USA. Pathogenic V. parahaemolyticus strains emerged also in Europe, but little is known about the abundance, pathogenicity and ecology of V. parahaemolyticus especially in Northern European waters. This study focuses on V. parahaemolyticus and its close relative Vibrio alginolyticus in the North Sea (Helgoland Roads, Germany). Free-living, plankton-attached and shellfish-associated Vibrio spp. were quantified between May 2008 and January 2010. CFUs up to 4.3 10(3) N l(-1) and MPNs up to 240 N g(-1) were determined. Phylogenetic classification based on rpoB gene sequencing revealed V. alginolyticus as the dominant Vibrio species at Helgoland Roads, followed by V. parahaemolyticus. We investigated the intraspecific diversity of V. parahaemolyticus and V. alginolyticus using ERIC-PCR. The fingerprinting disclosed three distinct groups at Helgoland Roads, representing V. parahaemolyticus, V. alginolyticus and one group in between. The species V. parahaemolyticus occurred mainly in summer months. None of the strains carried the virulence-associated genes tdh or trh. We further analyzed the influence of nutrients, secchi depth, temperature, salinity, chlorophyll a and phytoplankton on the abundance of Vibrio spp. and the population structure of V. parahaemolyticus. Spearman Rank analysis revealed that particularly temperature correlated significantly with Vibrio spp. numbers. Based on multivariate statistical analyses we report that the V. parahaemolyticus population was structured by a complex combination of environmental parameters. To further investigate these influences is the key to understanding the dynamics of Vibrio spp. in temperate European waters, where this microbial group and especially the pathogenic species, are likely to gain in importance. PMID:21598011

  19. 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

  20. Benthic ecology of Vibrio spp. and pathogenic Vibrio species in a coastal Mediterranean environment (La Spezia Gulf, Italy).

    PubMed

    Vezzulli, Luigi; Pezzati, Elisabetta; Moreno, Mariapaola; Fabiano, Mauro; Pane, Luigi; Pruzzo, Carla

    2009-11-01

    We carried out a 16-month in situ study to investigate the ecology of Vibrio spp. and pathogenic Vibrio species in coastal sediments of the Mediterranean Sea, employing multiple-regression analysis to reveal the major environmental factors controlling their occurrence in the benthic environment. In addition, association between vibrios and sediment-inhabiting meiofauna, which is a major component of benthic ecosystems, was investigated. Culturable and total Vibrio spp. estimates by most-probable-number technique coupled with standard polymerase chain reaction (PCR) and real-time PCR methods, respectively, were at least one order of magnitude higher in sediment than in seawater. In addition, potential human pathogenic species Vibrio cholerae, Vibrio vulnificus and Vibrio parahaemolyticus occurred in the sediment with V. parahaemolyticus being the most frequently found. In the pelagic environment, 60% of total variance in culturable Vibrio data was explained by sea surface temperature (40%), salinity (13%) and organic matter concentration (7%). In the benthic environment, sea surface temperature was the only factor that significantly affected culturable Vibrio occurrence although it explained only 25% of total variance, suggesting that additional unexplored factors may play a role as well. No correlation was found between culturable Vibrio spp. concentrations and the abundance of harpacticoid copepods in the sediment whilst a negative correlation was found between Vibrio spp. and nematode abundance which accounted for almost 90% of the total meiofaunal density. Taxonomic analysis revealed that selective bacterial feeders accounted for nearly 50% of the total nematode community and included genera such as Terschellingia, Molgolaimus and Halalaimus, suggesting that top-down control by nematode grazing may be an important factor affecting Vibrio occurrence in these sediments. It is concluded that the benthic marine environment may function as a reservoir of Vibrio spp. and potential pathogenic vibrios whose ecological features appeared substantially different from the ones recognised in the pelagic environment. PMID:19543938

  1. Vibrio parahaemolyticus cell biology and pathogenicity determinants.

    PubMed

    Broberg, Christopher A; Calder, Thomas J; Orth, Kim

    2011-11-01

    Vibrio parahaemolyticus is a significant cause of gastroenteritis worldwide. Characterization of this pathogen has revealed a unique repertoire of virulence factors that allow for colonization of the human host and disease. The following describes the known pathogenicity determinants while establishing the need for continued research. PMID:21782964

  2. 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...

  3. 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

  4. Thermal stress triggers broad Pocillopora damicornis transcriptomic remodeling, while Vibrio coralliilyticus infection induces a more targeted immuno-suppression response.

    PubMed

    Vidal-Dupiol, Jeremie; Dheilly, Nolwenn M; Rondon, Rodolfo; Grunau, Christoph; Cosseau, Cline; 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

  5. Not without cause: Vibrio parahaemolyticus induces acute autophagy and cell death.

    PubMed

    Burdette, Dara L; Yarbrough, Melanie L; Orth, Kim

    2009-01-01

    Vibrio parahaemolyticus (V. parahaemolyticus) is a gram-negative halophillic bacterium that causes worldwide seafood-borne gastroenteritis. The prevalence of V. parahaemolyticus in the environment and incidence of infection have been linked to rising water temperatures caused by global warming. Among its virulence factors, V. parahaemolyticus harbors two type III secretion systems (T3SS). Recently, we have shown that T3SS1 induces rapid cellular death that initiates with acute autophagy, as measured by LC3 lipidation and accumulation of early autophagosomal vesicles. While not the first characterized pathogen to usurp autophagy, this is the first example of an extracellular pathogen that exploits this pathway for its own benefit. Here we discuss possible roles for the induction of autophagy during infection and discuss how V. parahaemolyticus-induced autophagy provides insight into key regulatory steps that govern the decision between apoptosis and autophagy. PMID:19011375

  6. 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

  7. Factors Affecting the Uptake and Retention of Vibrio vulnificus in Oysters

    PubMed Central

    Noble, Rachel T.

    2014-01-01

    Vibrio vulnificus, a bacterium ubiquitous in oysters and coastal water, is capable of causing ailments ranging from gastroenteritis to grievous wound infections or septicemia. The uptake of these bacteria into oysters is often examined in vitro by placing oysters in seawater amended with V. vulnificus. Multiple teams have obtained similar results in studies where laboratory-grown bacteria were observed to be rapidly taken up by oysters but quickly eliminated. This technique, along with suggested modifications, is reviewed here. In contrast, the natural microflora within oysters is notoriously difficult to eliminate via depuration. The reason for the transiency of exogenous bacteria is that those bacteria are competitively excluded by the oyster's preexisting microflora. Evidence of this phenomenon is shown using in vitro oyster studies and a multiyear in situ case study. Depuration of the endogenous oyster bacteria occurs naturally and can also be artificially induced, but both of these events require extreme conditions, natural or otherwise, as explained here. Finally, the “viable but nonculturable” (VBNC) state of Vibrio is discussed. This bacterial torpor can easily be confused with a reduction in bacterial abundance, as bacteria in this state fail to grow on culture media. Thus, oysters collected from colder months may appear to be relatively free of Vibrio but in reality harbor VBNC cells that respond to exogenous bacteria and prevent colonization of oyster matrices. Bacterial-uptake experiments combined with studies involving cell-free spent media are detailed that demonstrate this occurrence, which could explain why the microbial community in oysters does not always mirror that of the surrounding water. PMID:25261513

  8. Stimulation of bacterial DNA synthesis by algal exudates in attached algal-bacterial consortia. [Amphora coffeaeformis; Vibrio proteolyticus

    SciTech Connect

    Murray, R.E.; Cooksey, K.E.; Priscu, J.C.

    1986-11-01

    Algal-bacterial consortia attached to polystyrene surfaces were prepared in the laboratory by using the marine diatom Amphora coffeaeformis and the marine bacterium Vibrio proteolytica (the approved name of this bacterium is Vibrio proteolyticus. The organisms were attached to the surfaces at cell densities of approximately 5 x 10/sup 4/ cells cm/sup -2/ (diatoms) and 5 x 10/sup 6/ cells cm/sup -2/ (bacteria). The algal-bacterial consortia consistently exhibited higher rates of (/sup 3/H)thymidine incorporation than did biofilms composed solely of bacteria. The rates of (/sup 3/H)thymidine incorporation by the algal-bacterial consortia were fourfold greater than the rates of incorporation by monobacterial biofilms 16 h after biofilm formation and were 16-fold greater 70 h after biofilm formation. Extracellular material released from the attached Amphora cells supported rates of bacterial activity (0.8 x 10/sup -21/ mol to 17.9 x 10/sup -21/ mol of (/sup 3/H)thymidine incorporated cell /sup -1/ h/sup -1/) and growth (doubling time, 29.5 to 1.4 days) comparable to values reported for a wide variety of marine and freshwater ecosystems. In the presence of sessile diatom populations, DNA synthesis by attached V. proteolytica cells was light dependent and increased with increasing algal abundance. The metabolic activity of diatoms thus appears to be the rate-limiting process in biofilm development on illuminated surfaces under conditions of low bulk-water dissolved organic carbon.

  9. Development of a quantitative real-time PCR assay for detection of Vibrio tubiashii targeting the metalloprotease gene.

    PubMed

    Gharaibeh, Dima N; Hasegawa, Hiroaki; Hse, Claudia C

    2009-03-01

    Vibrio tubiashii has recently re-emerged as a pathogen of bivalve larvae, causing a marked increase in the mortality of these species within shellfish rearing facilities. This has resulted in substantial losses of seed production and thus created the need for specific as well as sensitive detection methods for this pathogen. In this project, quantitative PCR (qPCR) primers were developed and optimized based upon analysis of the V. tubiashii vtpA gene sequence, encoding a metalloprotease known to cause larval mortality. Standard curves were developed utilizing dilutions of known quantities of V. tubiashii cells that were compared to colony forming unit (CFU) plate counts. The assay was optimized for detection of vtpA with both lab-grown V. tubiashii samples and filter-captured environmental seawater samples seeded with V. tubiashii. In addition, the primers were confirmed to specifically detect only V. tubiashii when tested against a variety of non-target Vibrio species. Validation of the assay was completed by analyzing samples obtained from a shellfish hatchery. The development of this rapid and sensitive assay for quantitative detection of V. tubiashii will accurately determine levels of this bacterium in a variety of seawater samples, providing a useful tool for oyster hatcheries and a method to assess the presence of this bacterium in the current turbulent ocean environment. PMID:19135097

  10. 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

  11. Broad Spectrum Pro-Quorum-Sensing Molecules as Inhibitors of Virulence in Vibrios

    PubMed Central

    Ng, Wai-Leung; Perez, Lark; Cong, Jianping; Semmelhack, Martin F.; Bassler, Bonnie L.

    2012-01-01

    Quorum sensing (QS) is a bacterial cell-cell communication process that relies on the production and detection of extracellular signal molecules called autoinducers. QS allows bacteria to perform collective activities. Vibrio cholerae, a pathogen that causes an acute disease, uses QS to repress virulence factor production and biofilm formation. Thus, molecules that activate QS in V. cholerae have the potential to control pathogenicity in this globally important bacterium. Using a whole-cell high-throughput screen, we identified eleven molecules that activate V. cholerae QS: eight molecules are receptor agonists and three molecules are antagonists of LuxO, the central NtrC-type response regulator that controls the global V. cholerae QS cascade. The LuxO inhibitors act by an uncompetitive mechanism by binding to the pre-formed LuxO-ATP complex to inhibit ATP hydrolysis. Genetic analyses suggest that the inhibitors bind in close proximity to the Walker B motif. The inhibitors display broad-spectrum capability in activation of QS in Vibrio species that employ LuxO. To the best of our knowledge, these are the first molecules identified that inhibit the ATPase activity of a NtrC-type response regulator. Our discovery supports the idea that exploiting pro-QS molecules is a promising strategy for the development of novel anti-infectives. PMID:22761573

  12. The dual nature of haemocyanin in the establishment and persistence of the squid–vibrio symbiosis

    PubMed Central

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

    2014-01-01

    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

  13. NMR-based microbial metabolomics and the temperature-dependent coral pathogen Vibrio coralliilyticus.

    PubMed

    Boroujerdi, Arezue F B; Vizcaino, Maria I; Meyers, Alexander; Pollock, Elizabeth C; Huynh, Sara Lien; Schock, Tracey B; Morris, Pamela J; Bearden, Daniel W

    2009-10-15

    Coral bleaching occurs when the symbioses between coral animals and their zooxanthellae is disrupted, either as part of a natural cycle or as the result of unusual events. The bacterium Vibrio coralliilyticus (type strain ATCC BAA-450) has been linked to coral disease globally (for example in the Mediterranean, Red Sea, Indian Ocean, and Great Barrier Reef) and like many other Vibrio species exhibits a temperature-dependent pathogenicity. The temperature-dependence of V. corallillyticus in regard to its metabolome was investigated. Nuclear magnetic resonance (NMR) spectra were obtained of methanol-water extracts of intracellula rmetabolites (endometabolome) from multiple samples of the bacteria cultured into late stationary phase at 27 degrees C (virulent form) and 24 degrees C (avirulent form). The spectra were subjected to principal components analysis (PCA), and significant temperature-based separations in PC1, PC2, and PC3 dimensions were observed. Betaine, succinate, and glutamate were identified as metabolites that caused the greatest temperature-based separations in the PC scores plots. With increasing temperature, betaine was shown to be down regulated, while succinate and glutamate were up regulated. PMID:19921875

  14. Recreational swimmers' exposure to Vibrio vulnificus and Vibrio parahaemolyticus in the Chesapeake Bay, Maryland, USA.

    PubMed

    Shaw, Kristi S; Sapkota, Amy R; Jacobs, John M; He, Xin; Crump, Byron C

    2015-01-01

    Vibrio vulnificus and Vibrio parahaemolyticus are ubiquitous in the marine-estuarine environment, but the magnitude of human non-ingestion exposure to these waterborne pathogens is largely unknown. We evaluated the magnitude of dermal exposure to V. vulnificus and V. parahaemolyticus among swimmers recreating in Vibrio-populated waters by conducting swim studies at four swimming locations in the Chesapeake Bay in 2009 and 2011. Volunteers (n=31) swam for set time periods, and surface water (n=25) and handwash (n=250) samples were collected. Samples were analyzed for Vibrio concentrations using quantitative PCR. Linear and logistic regressions were used to evaluate factors associated with recreational exposures. Mean surface water V. vulnificus and V. parahaemolyticus concentrations were 1128CFUmL(-1) (95% confidence interval (CI): 665.6, 1591.4) and 18CFUmL(-1) (95% CI: 9.8, 26.1), respectively, across all sampling locations. Mean Vibrio concentrations in handwash samples (V. vulnificus, 180CFUcm(-2) (95% CI: 136.6, 222.5); V. parahaemolyticus, 3CFUcm(-2) (95% CI: 2.4, 3.7)) were significantly associated with Vibrio concentrations in surface water (V. vulnificus, p<0.01; V. parahaemolyticus, p<0.01), but not with salinity or temperature (V. vulnificus, p=0.52, p=0.17; V. parahaemolyticus, p=0.82, p=0.06). Handwashing reduced V. vulnificus and V. parahaemolyticus on subjects' hands by approximately one log (93.9%, 89.4%, respectively). It can be concluded that when Chesapeake Bay surface waters are characterized by elevated concentrations of Vibrio, swimmers and individuals working in those waters could experience significant dermal exposures to V. vulnificus and V. parahaemolyticus, increasing their risk of infection. PMID:25454225

  15. A medium for presumptive identification of Vibrio anguillarum.

    PubMed Central

    Alsina, M; Martnez-Picado, J; Jofre, J; Blanch, A R

    1994-01-01

    A medium (VAM) for differentiation of Vibrio anguillarum is described. The presence of bile salts, the high pH, and the high NaCl concentration select mainly for Vibrio species. The high salinity and the ampicillin select for a fraction of Vibrio species, and sorbitol fermentation differentiates among those vibrios still able to grow. One hundred ninety-seven of 227 strains of V. anguillarum were identified with this medium. Only 3 of 66 strains of Vibrio that were not V. anguillarum or V. anguillarum-like were recognized with this medium, and any of 7 non-Vibrio strains related to fish diseases or Escherichia coli grew on the medium. It is our contention that the medium described here constitutes an efficient instrument for presumptive detection of V. anguillarum in pathological and environmental samples. PMID:8017947

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

    SciTech Connect

    Brettin, Thomas S; Bruce, David C; Challacombe, Jean F; Detter, John C; Han, Cliff S; Munik, A C; Chertkov, Olga; Meincke, Linda; Saunders, Elizabeth; Choi, Seon Y; Haley, Bradd J; Taviani, Elisa; Jeon, Yoon - Seong; Kim, Dong Wook; Lee, Jae - Hak; Walters, Ronald A; Hug, Anwar; 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 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.

  17. Mechanistic insights into filamentous phage integration in Vibrio cholerae.

    PubMed

    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

  18. 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

  19. 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; Ber, 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

  20. Copper homeostasis at the host vibrio interface: lessons from intracellular vibrio transcriptomics.

    PubMed

    Vanhove, Audrey S; Rubio, Tristan P; Nguyen, An N; Lemire, Astrid; Roche, David; Nicod, Julie; Vergnes, Agnès; Poirier, Aurore C; Disconzi, Elena; Bachère, Evelyne; Le Roux, Frédérique; Jacq, Annick; Charrière, Guillaume M; Destoumieux-Garzón, Delphine

    2016-03-01

    Recent studies revealed that several vibrio species have evolved the capacity to survive inside host cells. However, it is still often ignored if intracellular stages are required for pathogenicity. Virulence of Vibrio tasmaniensis LGP32, a strain pathogenic for Crassostrea gigas oysters, depends on entry into hemocytes, the oyster immune cells. We investigated here the mechanisms of LGP32 intracellular survival and their consequences on the host-pathogen interaction. Entry and survival inside hemocytes were required for LGP32-driven cytolysis of hemocytes, both in vivo and in vitro. LGP32 intracellular stages showed a profound boost in metabolic activity and a major transcription of antioxidant and copper detoxification genes, as revealed by RNA sequencing. LGP32 isogenic mutants showed that resistance to oxidative stress and copper efflux are two main functions required for vibrio intracellular stages and cytotoxicity to hemocytes. Copper efflux was also essential for host colonization and virulence in vivo. Altogether, our results identify copper resistance as a major mechanism to resist killing by phagocytes, induce cytolysis of immune cells and colonize oysters. Selection of such resistance traits could arise from vibrio interactions with copper-rich environmental niches including marine invertebrates, which favour the emergence of pathogenic vibrios resistant to intraphagosomal killing across animal species. PMID:26472275

  1. Highly diverse recombining populations of Vibrio cholerae and Vibrio parahaemolyticus in French Mediterranean coastal lagoons

    PubMed Central

    Esteves, Kévin; Mosser, Thomas; Aujoulat, Fabien; Hervio-Heath, Dominique; Monfort, Patrick; Jumas-Bilak, Estelle

    2015-01-01

    Vibrio parahaemolyticus and Vibrio cholerae are ubiquitous to estuarine and marine environments. These two species found in Mediterranean coastal systems can induce infections in humans. Environmental isolates of V. cholerae (n = 109) and V. parahaemolyticus (n = 89) sampled at different dates, stations and water salinities were investigated for virulence genes and by a multilocus sequence-based analysis (MLSA). V. cholerae isolates were all ctxA negative and only one isolate of V. parahaemolyticus displayed trh2 gene. Most Sequence Types (ST) corresponded to unique ST isolated at one date or one station. Frequent recombination events were detected among different pathogenic species, V. parahaemolyticus, V. cholerae, Vibrio mimicus, and Vibrio metoecus. Recombination had a major impact on the diversification of lineages. The genetic diversity assessed by the number of ST/strain was higher in low salinity condition for V. parahaemolyticus and V. cholerae whereas the frequency of recombination events in V. cholerae was lower in low salinity condition. Mediterranean coastal lagoon systems housed V. cholerae and V. parahaemolyticus with genetic diversities equivalent to the worldwide diversity described so far. The presence of STs found in human infections as well as the frequency of recombination events in environmental vibrios populations could predict a potential epidemiological risk. PMID:26236294

  2. Freshwater non-O1 Vibrio cholerae infection.

    PubMed

    Walker, Eric; Carpenter, John; Plemmons, Robert; Fader, Robert

    2010-10-01

    It is not appreciated by most physicians that vibrio infections can be acquired from freshwater exposure. A case of non-O1 Vibrio cholerae urinary tract infection associated with freshwater exposure is reported. The potential for vibrios to grow in brachish water and for summer heat to cause evaporation leading to relative increased salinity in freshwater bodies and the broad geographic range of these occurrences to include North American and both eastern and western Europe is noted. A literature review of vibrio infection acquired from freshwater exposure and the relationship to these epidemiologic and pathophysiologic events is discussed. PMID:20818301

  3. 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 (30C-32C) and as long as 9 days under refrigeration (5C-10C). 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

  4. [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

  5. 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)

  6. Vibrio species as agents of elasmobranch disease

    NASA Astrophysics Data System (ADS)

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

    1984-03-01

    Two Vibrio species identified as V. damsela and a new sucrose-positive Vibrio 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 hosts challenged. Virulence studies revealed that both bacterial strains were cytotoxic for Y-1 mouse adrenal cells. The V. damsela strain was highly cytotoxic causing Y-1 cellular damage at culture supernatant dilutions up to 1 : 128. Both strains were hemolytic, but neither exhibited the Kanagawa phenomenon. They were both capable of urea hydrolysis, an interesting trait, considering that elasmobranchs retain large (ca 300 milliosmolal) urea concentration in their tissue.

  7. 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

  8. Vibrio cholerae: Measuring Natural Transformation Frequency.

    PubMed

    Watve, Samit S; Bernardy, Eryn E; Hammer, Brian K

    2014-01-01

    Many bacteria can become naturally competent to take up extracellular DNA across their outer and inner membranes by a dedicated competence apparatus. Whereas some studies show that the DNA delivered to the cytoplasm may be used for genome repair or for nutrition, it can also be recombined onto the chromosome by homologous recombination: a process called natural transformation. Along with conjugation and transduction, natural transformation represents a mechanism for horizontal transfer of genetic material, e.g., antibiotic resistance genes, which can confer new beneficial characteristics onto the recipient bacteria. Described here are protocols for quantifying the frequency of transformation for the human pathogen Vibrio cholerae, one of several Vibrio species recently shown to be capable of natural transformation. PMID:25367272

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

    PubMed

    Wennberg, Aina Charlotte; Tryland, Ingun; stensvik, yvin; 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

  10. Nontoxigenic Vibrio parahaemolyticus Strains Causing Acute Gastroenteritis

    PubMed Central

    Leoni, Francesca; Serra, Roberto; Serracca, Laura; Decastelli, Lucia; Rocchegiani, Elena; Masini, Laura; Canonico, Cristina; Talevi, Giulia; Carraturo, Antonio

    2012-01-01

    We investigated the virulence properties of four Vibrio parahaemolyticus strains causing acute gastroenteritis following consumption of indigenous mussels in Italy. The isolated strains were cytotoxic and adhesive but, surprisingly, lacked tdh, trh, and type three secretion system 2 (T3SS2) genes. We emphasize that nontoxigenic V. parahaemolyticus can induce acute gastroenteritis, highlighting the need for more investigation of the pathogenicity of this microorganism. PMID:23052317

  11. Infections caused by halophilic marine Vibrio bacteria.

    PubMed Central

    Howard, R J; Bennett, N T

    1993-01-01

    OBJECTIVE: The authors reviewed patients who developed sepsis or soft tissue infections caused by marine Vibrio bacteria in Florida. SUMMARY BACKGROUND DATA: Marine Vibrio bacteria are the most common bacteria found in seawater. They are concentrated in marine animals that feed by filtration such as oysters and clams. These bacteria can cause gastroenteritis, sepsis, cellulitis leading to necrotizing soft tissue infection after exposure to seawater or consumption of raw seafood. METHODS: The authors received 182 systemic infections that occurred in Florida between January 1, 1979, and December 31, 1991, which were treated by the authors or were reported to the Florida Department of Health and Rehabilitative Services. Patients were divided into two groups depending on whether they presented with primary bacteremia or soft tissue infection. RESULTS: Seventy-one patients had been exposed to these bacteria by eating raw seafood, 94 had direct exposure to seawater, and exposure was uncertain in 27 patients. Vibrio species were cultured from the blood of 103 patients and from wounds or soft tissues of 113. An additional 5 patients had cellulitis but bacteria were not cultured from these sites. In patients in whom it could be determined, 93 had primary soft tissue infections and 82 had primary bacteremia. Twenty-four patients had necrotizing soft tissue infections and required surgical debridement. Three of these 24 patients required amputation. Thirty-seven (20.3%) patients died. Severe liver disease occurred in 54 patients and 25 of these patients died. CONCLUSIONS: Marine Vibrio bacteria can cause sepsis and soft tissue infections, especially in individuals with severe liver disease and other chronic illnesses such as diabetes mellitus. The authors believe all individuals, especially those with systemic illness, should be warned against eating raw seafood. Images Figure 1. PMID:8489315

  12. A Vibrio anguillarum strain associated with skin ulcer on cultured flounder, Paralichthys olivaceus

    NASA Astrophysics Data System (ADS)

    Mo, Zhao-Lan; Tan, Xun-Gang; Xu, Yong-Li; Zhang, Pei-Jun

    2001-12-01

    The characteristics of a bacterium strain M3, isolated from cultured flounder Paralichthys olivaceus with remarkable external sign of skin ulcer during an epizootic outbreak, indicated that the bacterium belonged to the species Vibrio anguillarum. Challenge by I.M. (intramuscular injection), bath, and oral administration with M3 showed that it was highly pathogenic for Paralichthys olivacues. The LD50 dose was 5.144×103 CFU/ per fish infection by I.M. injection. Recovered inoculated bacteria from the surviving fish revealed that the asymptomatic carriers could be a latent contagious source. Study of the effect of bacterial culture CFS (cell-free-supernatant) showed that the exotoxins produced by M3 play an important role in its pathogenicity for flounder. The resistance of M3 to 36 out of 41 antibiotics indicated that the bacterial disease outbreak was mainly attributable to the frequent and excessive use of antimicrobial agents; and that vaccination would be an effective precaution against bacterial disease.

  13. 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

  14. Survival of and in situ gene expression by Vibrio vulnificus at varying salinities in estuarine environments.

    PubMed

    Jones, Melissa K; Warner, Elizabeth; Oliver, James D

    2008-01-01

    The opportunistic human pathogen Vibrio vulnificus survives in a wide range of ecological environments, which demonstrates its ability to adapt to highly variable conditions. Survival and gene expression under various conditions have been extensively studied in vitro; however, little work has been done to evaluate this bacterium in its natural habitat. Therefore, this study monitored the long-term survival of V. vulnificus in situ and simultaneously evaluated the expression of stress (rpoS, relA, hfq, and groEL) and putative virulence (vvpE, smcR, viuB, and trkA) genes at estuarine sites of varying salinity. Additionally, the survival and gene expression of an rpoS and an oxyR mutant were examined under the same conditions. Differences between the sampling sites in the long-term survival of any strain were not seen. However, differences were seen in the expression of viuB, trkA, and relA but our findings differed from what has been previously shown in vitro. These results also routinely demonstrated that genes required for survival under in vitro stress or host conditions are not necessarily required for survival in the water column. Overall, this study highlights the need for further in situ evaluation of this bacterium in order to gain a true understanding of its ecology and how it relates to its natural habitat. PMID:17993554

  15. Role of type IV pilins in persistence of Vibrio vulnificus in Crassostrea virginica oysters.

    PubMed

    Paranjpye, Rohinee N; Johnson, Asta B; Baxter, Anne E; Strom, Mark S

    2007-08-01

    Vibrio vulnificus is part of the natural estuarine microflora and accumulates in shellfish through filter feeding. It is responsible for the majority of seafood-associated fatalities in the United States mainly through consumption of raw oysters. Previously we have shown that a V. vulnificus mutant unable to express PilD, the type IV prepilin peptidase, does not express pili on the surface of the bacterium and is defective in adherence to human epithelial cells (R. N. Paranjpye, J. C. Lara, J. C. Pepe, C. M. Pepe, and M. S. Strom, Infect. Immun. 66:5659-5668, 1998). A mutant unable to express one of the type IV pilins, PilA, is also defective in adherence to epithelial cells as well as biofilm formation on abiotic surfaces (R. N. Paranjpye and M. S. Strom, Infect. Immun. 73:1411-1422, 2005). In this study we report that the loss of PilD or PilA significantly reduces the ability of V. vulnificus to persist in Crassostrea virginica over a 66-h interval, strongly suggesting that pili expressed by this bacterium play a role in colonization or persistence in oysters. PMID:17557854

  16. Role of Anaerobiosis in Capsule Production and Biofilm Formation in Vibrio vulnificus

    PubMed Central

    Phippen, Britney L.

    2014-01-01

    Vibrio vulnificus, a pervasive human pathogen, can cause potentially fatal septicemia after consumption of undercooked seafood. Biotype 1 strains of V. vulnificus are most commonly associated with human infection and are separated into two genotypes, clinical (C) and environmental (E), based on the virulence-correlated gene. For ingestion-based vibriosis to occur, this bacterium must be able to withstand multiple conditions as it traverses the gastrointestinal tract and ultimately gains entry into the bloodstream. One such condition, anoxia, has yet to be extensively researched in V. vulnificus. We investigated the effect of oxygen availability on capsular polysaccharide (CPS) production and biofilm formation in this bacterium, both of which are thought to be important for disease progression. We found that lack of oxygen elicits a reduction in both CPS and biofilm formation in both genotypes. This is further supported by the finding that pilA, pilD, and mshA genes, all of which encode type IV pilin proteins that aid in attachment to surfaces, were downregulated during anaerobiosis. Surprisingly, E-genotypes exhibited distinct differences in gene expression levels of capsule and attachment genes compared to C-genotypes, both aerobically and anaerobically. The importance of understanding these disparities may give insight into the observed differences in environmental occurrence and virulence potential between these two genotypes of V. vulnificus. PMID:25404024

  17. The regulator HlyU, the repeat-in-toxin gene rtxA1, and their roles in the pathogenesis of Vibrio vulnificus infections

    PubMed Central

    Liu, Moqing; Crosa, Jorge H

    2012-01-01

    HlyU is a master regulator that plays an essential role in the virulence of the human pathogen Vibrio vulnificus. One of the most noteworthy characteristics of HlyU regulation in this organism is its positive control of the expression of the repeat-in-toxin (RtxA1) gene, one of the most important virulence factors accounting for the fulminating and damaging nature of V. vulnificus infections. In this work, we reviewed the latest studies of RtxA1 in this bacterium and highlight the mechanism of gene regulation of rtxA1 expression by HlyU under a broader gene regulatory network. PMID:23233275

  18. Basic studies on the viability of El Tor vibrios

    PubMed Central

    Miyaki, K.; Iwahara, S.; Sato, K.; Fujimoto, S.; Aibara, K.

    1967-01-01

    Quantitative data are presented on the viability of El Tor vibrios in various foodstuffs under different conditions. El Tor vibrios were found to have a very short life in water at -20C, but in various nutrient media, such as skim milk, sugar solution or meat extract, they could live for more than a month at this temperature; the survival rate was always much higher when the vibrio suspension was cooled rapidly to -72C and stored at this temperature. The optimum pH for the growth and survival of El Tor vibrios is 6-8, and the optimum osmotic pressure 250 mOsm700 mOsm. The resistance of El Tor vibrios to disinfectants is lower than that of salmonellae and Escherichia coli. The El Tor vibrios are more resistant than classical cholera vibrios to such disinfectants as benzethonium chloride and o-dichlorobenzene. They are not resistant to sodium hypochlorite or bleaching powder at 6 ppm. The results of the investigation emphasize the necessity of immediate and proper disinfection of foodstuffs contaminated with El Tor vibrios, and indicate the possibility of survival of the organisms for long periods under favourable conditions. PMID:4870080

  19. Intracranial infection by Vibrio alginolyticus following injury in salt water.

    PubMed Central

    Opal, S M; Saxon, J R

    1986-01-01

    A 20-year-old man presented with an epidural abscess 3 months after a seawater diving accident. Cultures of the abscess cavity obtained by surgical drainage revealed a pure culture of Vibrio alginolyticus. Marine vibrios may produce serious intracranial infection after head injury in salt water. PMID:3700619

  20. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vibrio cholerae serological reagents. 866.3930 Section 866.3930 Food and Drugs 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....

  1. Comparison of the heme iron utilization systems of pathogenic Vibrios.

    PubMed

    O'Malley, S M; Mouton, S L; Occhino, D A; Deanda, M T; Rashidi, J R; Fuson, K L; Rashidi, C E; Mora, M Y; Payne, S M; Henderson, D P

    1999-06-01

    Vibrio alginolyticus, Vibrio fluvialis, and Vibrio parahaemolyticus utilized heme and hemoglobin as iron sources and contained chromosomal DNA similar to several Vibrio cholerae heme iron utilization genes. A V. parahaemolyticus gene that performed the function of V. cholerae hutA was isolated. A portion of the tonB1 locus of V. parahaemolyticus was sequenced and found to encode proteins similar in amino acid sequence to V. cholerae HutW, TonB1, and ExbB1. A recombinant plasmid containing the V. cholerae tonB1 and exbB1D1 genes complemented a V. alginolyticus heme utilization mutant. These data suggest that the heme iron utilization systems of the pathogenic vibrios tested, particularly V. parahaemolyticus and V. alginolyticus, are similar at the DNA level, the functional level, and, in the case of V. parahaemolyticus, the amino acid sequence or protein level to that of V. cholerae. PMID:10348876

  2. Comparison of the Heme Iron Utilization Systems of Pathogenic Vibrios

    PubMed Central

    OMalley, S. M.; Mouton, S. L.; Occhino, D. A.; Deanda, M. T.; Rashidi, J. R.; Fuson, K. L.; Rashidi, C. E.; Mora, M. Y.; Payne, S. M.; Henderson, D. P.

    1999-01-01

    Vibrio alginolyticus, Vibrio fluvialis, and Vibrio parahaemolyticus utilized heme and hemoglobin as iron sources and contained chromosomal DNA similar to several Vibrio cholerae heme iron utilization genes. A V. parahaemolyticus gene that performed the function of V. cholerae hutA was isolated. A portion of the tonB1 locus of V. parahaemolyticus was sequenced and found to encode proteins similar in amino acid sequence to V. cholerae HutW, TonB1, and ExbB1. A recombinant plasmid containing the V. cholerae tonB1 and exbB1D1 genes complemented a V. alginolyticus heme utilization mutant. These data suggest that the heme iron utilization systems of the pathogenic vibrios tested, particularly V. parahaemolyticus and V. alginolyticus, are similar at the DNA level, the functional level, and, in the case of V. parahaemolyticus, the amino acid sequence or protein level to that of V. cholerae. PMID:10348876

  3. Pertinence of indicator organisms and sampling variables to Vibrio concentrations.

    PubMed Central

    Koh, E G; Huyn, J H; LaRock, P A

    1994-01-01

    Vibrio-indicator relationships and effects of day, depth, and tidal levels on the density of vibrios enumerated by the most probable number technique were investigated. Counts of vibrios taken monthly from Apalachicola Bay, Fla., were either negatively correlated or showed no correlation with counts of indicator bacteria (Escherichia coli, enterococci, fecal coliforms, and total coliforms). Water samples collected on two days from the surface and bottom over a complete tidal cycle on each day were analyzed for differences in vibrio concentrations. Concentrations of vibrios in samples taken on different days, in those taken at different depths, and in those taken at different tidal levels were significantly different, indicating that these factors need to be taken into account in health-related studies. PMID:7986059

  4. 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

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

    PubMed

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

    2000-02-15

    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. PMID:10677480

  6. 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.

  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. Environmental occurrence and clinical impact of Vibrio vulnificus and Vibrio parahaemolyticus: a European perspective.

    PubMed

    Baker-Austin, Craig; Stockley, Louise; Rangdale, Rachel; Martinez-Urtaza, Jaime

    2010-02-01

    Vibrio vulnificus and Vibrio parahaemolyticus are ubiquitous Gram-negative bacterial pathogens found naturally in marine and estuarine waters, and are a leading cause of seafood-associated bacterial illness. These pathogens are commonly reported in the USA and in many Asian countries, including China, Japan and Taiwan; however, there is growing concern that V. vulnificus and V. parahaemolyticus may represent an important and increasing clinical problem in Europe. Several factors underlie the need for a greater understanding of these non-cholera vibrios within a European context. First, there is a growing body of evidence to suggest that V. vulnificus and V. parahaemolyticus infections are increasing, and tend to follow regional climatic trends, with outbreaks typically following episodes of unusually warm weather. Such findings are especially alarming given current predictions regarding warming of marine waters as a result of global climatic change. Second, a myriad of epidemiological factors may greatly increase the incidence as well as clinical burden of these pathogens - including increasing global consumption and trade of seafood produce coupled to an increase in the number of susceptible individuals consuming seafood produce. Finally, there is currently a lack of detailed surveillance information regarding non-cholerae Vibrio infections in Europe, as these pathogens are not notifiable in many countries, which probably masks the true clinical burden of many human infections. This review will present a pertinent overview of both the environmental occurrence and clinical impact of V. vulnificus and V. parahaemolyticus in Europe. PMID:23765993

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

    PubMed Central

    Mansergh, Sarah; Zehr, Jonathan P.

    2013-01-01

    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 2006April 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

  10. 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

  11. 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.

  12. 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 30C 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

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

    PubMed

    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

    2012-09-01

    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 30C 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

  14. 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.

  15. Chitin induces natural competence in Vibrio cholerae.

    PubMed

    Meibom, Karin L; Blokesch, Melanie; Dolganov, Nadia A; Wu, Cheng-Yen; Schoolnik, Gary K

    2005-12-16

    The mosaic-structured Vibrio cholerae genome points to the importance of horizontal gene transfer (HGT) in the evolution of this human pathogen. We showed that V. cholerae can acquire new genetic material by natural transformation during growth on chitin, a biopolymer that is abundant in aquatic habitats (e.g., from crustacean exoskeletons), where it lives as an autochthonous microbe. Transformation competence was found to require a type IV pilus assembly complex, a putative DNA binding protein, and three convergent regulatory cascades, which are activated by chitin, increasing cell density, and nutrient limitation, a decline in growth rate, or stress. PMID:16357262

  16. The Role of Vibrios in Diseases of Corals.

    PubMed

    Munn, Colin B

    2015-08-01

    The tissue, skeleton, and secreted mucus of corals supports a highly dynamic and diverse community of microbes, which play a major role in the health status of corals such as the provision of essential nutrients or the metabolism of waste products. However, members of the Vibrio genus are prominent as causative agents of disease in corals. The aim of this chapter is to review our understanding of the spectrum of disease effects displayed by coral-associated vibrios, with a particular emphasis on the few species where detailed studies of pathogenicity have been conducted. The role of Vibrio shilonii in seasonal bleaching of Oculina patagonica and the development of the coral probiotic hypothesis is reviewed, pointing to unanswered questions about this phenomenon. Detailed consideration is given to studies of V. coralliilyticus and related pathogens and changes in the dominance of vibrios associated with coral bleaching. Other Vibrio-associated disease syndromes discussed include yellow band/blotch disease and tissue necrosis in temperate gorgonian corals. The review includes analysis of the role of enzymes, resistance to oxidative stress, and quorum sensing in virulence of coral-associated vibrios. The review concludes that we should probably regard most-possibly all-vibrios as "opportunistic" pathogens which, under certain environmental conditions, are capable of overwhelming the defense mechanisms of appropriate hosts, leading to rapid growth and tissue destruction. PMID:26350314

  17. Vibrio Iron Transport: Evolutionary Adaptation to Life in Multiple Environments.

    PubMed

    Payne, Shelley M; Mey, Alexandra R; Wyckoff, Elizabeth E

    2016-03-01

    Iron is an essential element for Vibrio spp., but the acquisition of iron is complicated by its tendency to form insoluble ferric complexes in nature and its association with high-affinity iron-binding proteins in the host. Vibrios occupy a variety of different niches, and each of these niches presents particular challenges for acquiring sufficient iron. Vibrio species have evolved a wide array of iron transport systems that allow the bacteria to compete for this essential element in each of its habitats. These systems include the secretion and uptake of high-affinity iron-binding compounds (siderophores) as well as transport systems for iron bound to host complexes. Transporters for ferric and ferrous iron not complexed to siderophores are also common to Vibrio species. Some of the genes encoding these systems show evidence of horizontal transmission, and the ability to acquire and incorporate additional iron transport systems may have allowed Vibrio species to more rapidly adapt to new environmental niches. While too little iron prevents growth of the bacteria, too much can be lethal. The appropriate balance is maintained in vibrios through complex regulatory networks involving transcriptional repressors and activators and small RNAs (sRNAs) that act posttranscriptionally. Examination of the number and variety of iron transport systems found in Vibrio spp. offers insights into how this group of bacteria has adapted to such a wide range of habitats. PMID:26658001

  18. Function and Regulation of Vibrio campbellii Proteorhodopsin: Acquired Phototrophy in a Classical Organoheterotroph

    PubMed Central

    Wang, Zheng; O'Shaughnessy, Thomas J.; Soto, Carissa M.; Rahbar, Amir M.; Robertson, Kelly L.; Lebedev, Nikolai; Vora, Gary J.

    2012-01-01

    Proteorhodopsins (PRs) are retinal-binding photoproteins that mediate light-driven proton translocation across prokaryotic cell membranes. Despite their abundance, wide distribution and contribution to the bioenergy budget of the marine photic zone, an understanding of PR function and physiological significance in situ has been hampered as the vast majority of PRs studied to date are from unculturable bacteria or culturable species that lack the tools for genetic manipulation. In this study, we describe the presence and function of a horizontally acquired PR and retinal biosynthesis gene cluster in the culturable and genetically tractable bioluminescent marine bacterium Vibrio campbellii. Pigmentation analysis, absorption spectroscopy and photoinduction assays using a heterologous over-expression system established the V. campbellii PR as a functional green light absorbing proton pump. In situ analyses comparing PR expression and function in wild type (WT) V. campbellii with an isogenic ?pR deletion mutant revealed a marked absence of PR membrane localization, pigmentation and light-induced proton pumping in the ?pR mutant. Comparative photoinduction assays demonstrated the distinct upregulation of pR expression in the presence of light and PR-mediated photophosphorylation in WT cells that resulted in the enhancement of cellular survival during respiratory stress. In addition, we demonstrate that the master regulator of adaptive stress response and stationary phase, RpoS1, positively regulates pR expression and PR holoprotein pigmentation. Taken together, the results demonstrate facultative phototrophy in a classical marine organoheterotrophic Vibrio species and provide a salient example of how this organism has exploited lateral gene transfer to further its adaptation to the photic zone. PMID:22741028

  19. Genome anatomy of the gastrointestinal pathogen, Vibrio parahaemolyticus of crustacean origin

    PubMed Central

    2013-01-01

    Vibrio parahaemolyticus, an important human pathogen, is associated with gastroenteritis and transmitted through partially cooked seafood. It has become a major concern in the production and trade of marine food products. The prevalence of potentially virulent and pathogenic V. parahaemolyticus in raw seafood is of public health significance. Here we describe the genome sequence of a V. parahaemolyticus isolate of crustacean origin which was cultured from prawns in 2008 in Selangor, Malaysia (isolate PCV08-7). The next generation sequencing and analysis revealed that the genome of isolate PCV08-7 has closest similarity to that of V. parahaemolyticus RIMD2210633. However, there are certain unique features of the PCV08-7 genome such as the absence of TDH-related hemolysin (TRH), and the presence of HU-alpha insertion. The genome of isolate PCV08-7 encodes a thermostable direct hemolysin (TDH), an important virulence factor that classifies PCV08-7 isolate to be a serovariant of O3:K6 strain. Apart from these, we observed that there is certain pattern of genetic rearrangements that makes V. parahaemolyticus PCV08-7 a non-pandemic clone. We present detailed genome statistics and important genetic features of this bacterium and discuss how its survival, adaptation and virulence in marine and terrestrial hosts can be understood through the genomic blueprint and that the availability of genome sequence entailing this important Malaysian isolate would likely enhance our understanding of the epidemiology, evolution and transmission of foodborne Vibrios in Malaysia and elsewhere. PMID:24330647

  20. Vitroprocines, new antibiotics against Acinetobacter baumannii, discovered from marine Vibrio sp. QWI-06 using mass-spectrometry-based metabolomics approach

    PubMed Central

    Liaw, Chih-Chuang; Chen, Pei-Chin; Shih, Chao-Jen; Tseng, Sung-Pin; Lai, Ying-Mi; Hsu, Chi-Hsin; Dorrestein, Pieter C.; Yang, Yu-Liang

    2015-01-01

    A robust and convenient research strategy integrating state-of-the-art analytical techniques is needed to efficiently discover novel compounds from marine microbial resources. In this study, we identified a series of amino-polyketide derivatives, vitroprocines A-J, from the marine bacterium Vibrio sp. QWI-06 by an integrated approach using imaging mass spectroscopy and molecular networking, as well as conventional bioactivity-guided fractionation and isolation. The structure-activity relationship of vitroprocines against Acinetobacter baumannii is proposed. In addition, feeding experiments with 13C-labeled precursors indicated that a pyridoxal 5?-phosphate-dependent mechanism is involved in the biosynthesis of vitroprocines. Elucidation of amino-polyketide derivatives from a species of marine bacteria for the first time demonstrates the potential of this integrated metabolomics approach to uncover marine bacterial biodiversity. PMID:26238555

  1. Vitroprocines, new antibiotics against Acinetobacter baumannii, discovered from marine Vibrio sp. QWI-06 using mass-spectrometry-based metabolomics approach

    NASA Astrophysics Data System (ADS)

    Liaw, Chih-Chuang; Chen, Pei-Chin; Shih, Chao-Jen; Tseng, Sung-Pin; Lai, Ying-Mi; Hsu, Chi-Hsin; Dorrestein, Pieter C.; Yang, Yu-Liang

    2015-08-01

    A robust and convenient research strategy integrating state-of-the-art analytical techniques is needed to efficiently discover novel compounds from marine microbial resources. In this study, we identified a series of amino-polyketide derivatives, vitroprocines A-J, from the marine bacterium Vibrio sp. QWI-06 by an integrated approach using imaging mass spectroscopy and molecular networking, as well as conventional bioactivity-guided fractionation and isolation. The structure-activity relationship of vitroprocines against Acinetobacter baumannii is proposed. In addition, feeding experiments with 13C-labeled precursors indicated that a pyridoxal 5‧-phosphate-dependent mechanism is involved in the biosynthesis of vitroprocines. Elucidation of amino-polyketide derivatives from a species of marine bacteria for the first time demonstrates the potential of this integrated metabolomics approach to uncover marine bacterial biodiversity.

  2. Temporal and spatial variability in the distribution of Vibrio vulnificus in the Chesapeake Bay: a hindcast study.

    PubMed

    Banakar, Vinita; Constantin de Magny, Guillaume; Jacobs, John; Murtugudde, Raghu; Huq, Anwar; Wood, Robert J; Colwell, Rita R

    2011-12-01

    Vibrio vulnificus, an estuarine bacterium, is the causative agent of seafood-related gastroenteritis, primary septicemia, and wound infections worldwide. It occurs as part of the normal microflora of coastal marine environments and can be isolated from water, sediment, and oysters. Hindcast prediction was undertaken to determine spatial and temporal variability in the likelihood of occurrence of V. vulnificus in surface waters of the Chesapeake Bay. Hindcast predictions were achieved by forcing a multivariate habitat suitability model with simulated sea surface temperature and salinity in the Bay for the period between 1991 and 2005 and the potential hotspots of occurrence of V. vulnificus in the Chesapeake Bay were identified. The likelihood of occurrence of V. vulnificus during high and low rainfall years was analyzed. From results of the study, it is concluded that hindcast prediction yields an improved understanding of environmental conditions associated with occurrence of V. vulnificus in the Chesapeake Bay. PMID:22302219

  3. Extraintestinal Infections Caused by Non-toxigenic Vibrio cholerae non-O1/non-O139

    PubMed Central

    Chowdhury, Goutam; Joshi, Sangeeta; Bhattacharya, Sanjay; Sekar, Uma; Birajdar, Balaji; Bhattacharyya, Arpita; Shinoda, Sumio; Ramamurthy, Thandavarayan

    2016-01-01

    Vibrio cholerae is an aerobic, sucrose fermentative Gram-negative bacterium that generally prevails in the environment. Pathogenic V. cholerae is well-known as causative agent of acute diarrhea. Apart from enteric infections, V. cholerae may also cause other diseases. However, their role in causing extraintestinal infections is not fully known as it needs proper identification and evaluation. Four cases of extraintestinal infections due to V. cholerae non-O1/non-O139 have been investigated. The isolates were screened for phenotypic and genetic characteristics with reference to their major virulence genes. Serologically distinct isolates harbored rtx, msh, and hly but lacked enteric toxin encoding genes that are generally present in toxigenic V. cholerae. Timely detection of this organism can prevent fatalities in hospital settings. The underlying virulence potential of V. cholerae needs appropriate testing and intervention. PMID:26904017

  4. Structure of Vibrio cholerae ToxT reveals a mechanism for fatty acid regulation of virulence genes

    SciTech Connect

    Lowden, Michael J.; Skorupski, Karen; Pellegrini, Maria; Chiorazzo, Michael G.; Taylor, Ronald K.; Kull, F. Jon

    2010-03-04

    Cholera is an acute intestinal infection caused by the bacterium Vibrio cholerae. In order for V. cholerae to cause disease, it must produce two virulence factors, the toxin-coregulated pilus (TCP) and cholera toxin (CT), whose expression is controlled by a transcriptional cascade culminating with the expression of the AraC-family regulator, ToxT. We have solved the 1.9 {angstrom} resolution crystal structure of ToxT, which reveals folds in the N- and C-terminal domains that share a number of features in common with AraC, MarA, and Rob as well as the unexpected presence of a buried 16-carbon fatty acid, cis-palmitoleate. The finding that cis-palmitoleic acid reduces TCP and CT expression in V. cholerae and prevents ToxT from binding to DNA in vitro provides a direct link between the host environment of V. cholerae and regulation of virulence gene expression.

  5. Autophagy plays an important role in protecting Pacific oysters from OsHV-1 and Vibrio aestuarianus infections

    PubMed Central

    Moreau, Pierrick; Moreau, Kevin; Segarra, Amlie; Tourbiez, Delphine; Travers, Marie-Agns; Rubinsztein, David C; Renault, Tristan

    2015-01-01

    Recent mass mortality outbreaks around the world in Pacific oysters, Crassostrea gigas, have seriously affected the aquaculture economy. Although the causes for these mortality outbreaks appear complex, infectious agents are involved. Two pathogens are associated with mass mortality outbreaks, the virus ostreid herpesvirus 1 (OsHV-1) and the bacterium Vibrio aestuarianus. Here we describe the interactions between these 2 pathogens and autophagy, a conserved intracellular pathway playing a key role in innate immunity. We show for the first time that autophagy pathway is present and functional in Pacific oysters and plays an important role to protect animals from infections. This study contributes to better understand the innate immune system of Pacific oysters. PMID:25714877

  6. Extraintestinal Infections Caused by Non-toxigenic Vibrio cholerae non-O1/non-O139.

    PubMed

    Chowdhury, Goutam; Joshi, Sangeeta; Bhattacharya, Sanjay; Sekar, Uma; Birajdar, Balaji; Bhattacharyya, Arpita; Shinoda, Sumio; Ramamurthy, Thandavarayan

    2016-01-01

    Vibrio cholerae is an aerobic, sucrose fermentative Gram-negative bacterium that generally prevails in the environment. Pathogenic V. cholerae is well-known as causative agent of acute diarrhea. Apart from enteric infections, V. cholerae may also cause other diseases. However, their role in causing extraintestinal infections is not fully known as it needs proper identification and evaluation. Four cases of extraintestinal infections due to V. cholerae non-O1/non-O139 have been investigated. The isolates were screened for phenotypic and genetic characteristics with reference to their major virulence genes. Serologically distinct isolates harbored rtx, msh, and hly but lacked enteric toxin encoding genes that are generally present in toxigenic V. cholerae. Timely detection of this organism can prevent fatalities in hospital settings. The underlying virulence potential of V. cholerae needs appropriate testing and intervention. PMID:26904017

  7. Growth of Vibrio cholerae O1 Ogawa Eltor in freshwater.

    PubMed

    Vital, Marius; Fchslin, Hans Peter; Hammes, Frederik; Egli, Thomas

    2007-07-01

    Growth of Vibrio cholerae O1 Ogawa Eltor was studied with a growth assay in which autoclaved and filtered (0.22 microm) freshwater was inoculated at low cell density (5 x 10(3) cells ml(-1)) and proliferation was followed with flow cytometry. Against the common view, V. cholerae was able to grow extensively in different kinds of freshwater. The bacterium multiplied in river water, lake water and effluent of a wastewater treatment plant up to a cell density of 1.55 x 10(6) cells ml(-1). In these samples, apparent assimilable organic carbon (AOC(app)) concentrations ranged from 52 up to 800 microg l(-1) and the results demonstrate a positive trend between the AOC(app) concentration and final cell concentration, suggesting that AOC was a key parameter governing growth of V. cholerae. No growth was observed in waters (tap and bottled drinking water) containing less than approximately 60 microg AOC(app) l(-1). When pure cultures of V. cholerae were grown on identical lake water at different temperatures (20, 25 and 30 degrees C) the maximum specific growth rates (micromax) achieved were 0.22 h(-1), 0.32 h(-1) and 0.45 h(-1), respectively. In addition, growth was characterized in lake water samples amended with different concentrations of NaCl. The highest micromax of V. cholerae was recorded at moderate salinity levels (5 g NaCl l(-1), micromax=0.84 h(-1)), whereas at 30 g NaCl l(-1) (micromax=0.30 h(-1)) or 0 g NaCl l(-1) (micromax)=0.40 h(-1)) specific growth rates were significantly reduced. In the water tested here, micro(max) of V. cholerae was always around 50 % of that exhibited by a freshwater community of indigenous bacteria enriched from the water sampling site. Direct batch competition experiments between V. cholerae and the lake water bacterial community were performed at different temperatures in which V. cholerae was enumerated in the total community using fluorescent-surface antibodies. In all cases V. cholerae was able to grow and constituted around 10 % of the final total cell concentration of the community. No significant effect of temperature was observed on the outcome of the competition. Mathematical modelling of the competition at the different temperatures based on the calculated micromax values confirmed these experimental observations. The results demonstrate that V. cholerae is not only able to survive, but also able to grow in freshwater samples. In these experiments the bacterium was able to use a large fraction (12-62 %) of the AOC(app) available to the bacterial AOC-test community, indicating that V. cholerae has the ability to gain access to the substrates present in freshwater even in competition with an autochthonous bacterial lake water consortium. PMID:17600045

  8. Association Properties and Unfolding of a βγ-Crystallin Domain of a Vibrio-Specific Protein

    PubMed Central

    Suman, Shashi Kumar; Ravindra, Daddali; Sharma, Yogendra; Mishra, Amita

    2013-01-01

    The βγ-crystallin superfamily possesses a large number of versatile members, of which only a few members other than lens βγ-crystallins have been studied. Understanding the non-crystallin functions as well as origin of crystallin-like properties of such proteins is possible by exploring novel members from diverse sources. We describe a novel βγ-crystallin domain with S-type (Spherulin 3a type) Greek key motifs in protein vibrillin from a pathogenic bacterium Vibrio cholerae. This domain is a part of a large Vibrio-specific protein prevalent in Vibrio species (found in at least fourteen different strains sequenced so far). The domain contains two canonical N/D-N/D-X-X-S/T-S Ca2+-binding motifs, and bind Ca2+. Unlike spherulin 3a and other microbial homologues studied so far, βγ-crystallin domain of vibrillin self-associates forming oligomers of various sizes including dimers. The fractionated dimers readily form octamers in concentration-dependent manner, suggesting an association between these two major forms. The domain associates/dissociates forming dimers at the cost of monomeric populations in the presence of Ca2+. No such effect of Ca2+ has been observed in oligomeric species. The equilibrium unfolding of both forms follows a similar pattern, with the formation of an unfolding intermediate at sub-molar concentrations of denaturant. These properties exhibited by this βγ-crystallin domain are not shown by any other domain studied so far, demonstrating the diversity in domain properties. PMID:23349723

  9. Adherence assays and Slime production of Vibrio alginolyticus and Vibrio parahaemolyticus.

    PubMed

    Ben Abdallah, Fethi; Chaieb, Kamel; Zmantar, Tarek; Kallel, Hela; Bakhrouf, Amina

    2009-04-01

    In this study we investigated the phenotypic slime production of Vibrio alginolyticus and Vibrio parahaemolyticus strains, food-borne pathogens, using a Congo red agar plate assay. Furthermore, we studied their ability to adhere to abiotic surfaces and Vero cells line. Our results showed that only V. alginolyticus ATCC 17749 was a slime-producer developing almost black colonies on Congo red agar plate. Adherence to glace tube showed that all V. alginolyticus strains were more adherent than V. parahaemolyticus. Only V. alginolyticus ATCC 17749 was found to be able to form biofilm on polystyrene microplate wells (OD570 = 0.532). Adherence to Vero cells showed that all tested strains were non adherent after 30 min, however after 60 min all the studied strains become adherent. The percentage of adherence ranged from1.23% to 4.66%. PMID:24031378

  10. Occurrence of Vibrio vulnificus and toxigenic Vibrio parahaemolyticus on sea catfishes from Galveston Bay, Texas.

    PubMed

    Baumeister, Leslie; Hochman, Mona E; Schwarz, John R; Brinkmeyer, Robin

    2014-10-01

    Dorsal and pectoral fin spines from two species of sea catfishes (Bagre marinus and Ariopsis felis) landed at 54 sites in Galveston Bay, Texas, and its sub-bays from June to October 2005 were screened with traditional cultivation-based assays and quantitative PCR assays for Vibrio vulnificus and Vibrio parahaemolyticus. V. vulnificus was present on 51.2% of fish (n = 247), with an average of 403 ± 337 SD cells g(-1). V. parahaemolyticus was present on 94.2% (n = 247); 12.8% tested positive for the virulence-conferring tdh gene, having an average 2,039 ± 2,171 SD cells g(-1). The increasing trend in seafood consumption of "trash fishes" from lower trophic levels, such as sea catfishes, warrants evaluation of their life histories for association with pathogens of concern for human consumption. PMID:25285498

  11. Oleic Acid Produced by a Marine Vibrio spp. Acts as an Anti-Vibrio parahaemolyticus Agent

    PubMed Central

    Leyton, Yanett; Borquez, Jorge; Darias, Jos; Cueto, Mercedes; Daz-Marrero, Ana R.; Riquelme, Carlos

    2011-01-01

    It is known that some strains of Vibrio parahaemolyticus are responsible for gastroenteric diseases caused by the ingestion of marine organisms contaminated with these bacterial strains. Organic products that show inhibitory activity on the growth of the pathogenic V. parahaemolyticus were extracted from a Vibrio native in the north of Chile. The inhibitory organic products were isolated by reverse phase chromatography and permeation by Sephadex LH20, and were characterized by spectroscopic and spectrometric techniques. The results showed that the prevailing active product is oleic acid, which was compared with standards by gas chromatography and high-performance liquid chromatography (HPLC). These active products might be useful for controlling the proliferation of pathogenic clones of V. parahaemolyticus. PMID:22073014

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

    PubMed Central

    Khn, 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

  13. Evaluation of monoclonal antibody based immunochromatographic strip test for direct detection of Vibrio cholerae O1 contamination in seafood samples.

    PubMed

    Chaivisuthangkura, Parin; Pengsuk, Chalinan; Longyant, Siwaporn; Sithigorngul, Paisarn

    2013-11-01

    A strip test for the detection of Vibrio cholerae O1 was developed using two monoclonal antibodies (MAbs), VC-223 and VC-1226, specific to the lipopolysaccharides of Vibrio cholerae O1 Inaba and Ogawa serovars. The sensitivity of the test was 5 10(5)cfu/mL which was similar to that of dot blot test. The detection limit could be improved to 1cfu/mL of the original bacterial content after pre-incubation of the bacterium in alkaline peptone water (APW) for 12h. Detection of V. cholerae O1 in various fresh seafood samples such as shrimp, blood clam, mussel and oyster could be performed directly with sensitivities ranged from 5 10(5) to 10(6)cfu/mL. After pre-enrichment of the shrimp sample in APW, the detection sensitivities increased to 10(2) to 10CFU/mL of the original bacterial content after incubation for 12 and 24h. However, the detection sensitivities were also depending on the content of the other bacteria that might inhibit the growth of V. cholerae during pre-enrichment step. The V. cholerae O1 strip test has advantages in speed, and simplicity in not requiring sophisticated equipment or specialized skills and the sample could be directly examined without requirement for sample processing. PMID:24060694

  14. Activities of Alkyl Hydroperoxide Reductase Subunits C1 and C2 of Vibrio parahaemolyticus against Different Peroxides

    PubMed Central

    Chung, Chun-Hui; Ma, Tsung-yong; Fen, Shin-yuan

    2014-01-01

    Alkyl hydroperoxide reductase subunit C gene (ahpC) functions were characterized in Vibrio parahaemolyticus, a commonly occurring marine food-borne enteropathogenic bacterium. Two ahpC genes, ahpC1 (VPA1683) and ahpC2 (VP0580), encoded putative two-cysteine peroxiredoxins, which are highly similar to the homologous proteins of Vibrio 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 mutant and ahpC1 ahpC2 double mutant in liquid medium was significantly inhibited by organic peroxides, cumene hydroperoxide and tert-butyl hydroperoxide. However, inhibition was higher at 12C and 22C than at 37C. 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 ahpC1 ahpC2 mutant at 22C. 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

  15. 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

  16. 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

  17. The Vibrio parahaemolyticus Type III Secretion Systems manipulate host cell MAPK for critical steps in pathogenesis

    PubMed Central

    2010-01-01

    Background Vibrio parahaemolyticus is a food-borne pathogen causing inflammation of the gastrointestinal epithelium. Pathogenic strains of this bacterium possess two Type III Secretion Systems (TTSS) that deliver effector proteins into host cells. In order to better understand human host cell responses to V. parahaemolyticus, the modulation of Mitogen Activated Protein Kinase (MAPK) activation in epithelial cells by an O3:K6 clinical isolate, RIMD2210633, was investigated. The importance of MAPK activation for the ability of the bacterium to be cytotoxic and to induce secretion of Interleukin-8 (IL-8) was determined. Results V. parahaemolyticus deployed its TTSS1 to induce activation of the JNK, p38 and ERK MAPK in human epithelial cells. VP1680 was identified as the TTSS1 effector protein responsible for MAPK activation in Caco-2 cells and the activation of JNK and ERK by this protein was important in induction of host cell death. V. parahaemolyticus actively induced IL-8 secretion in a response mediated by TTSS1. A role for VP1680 and for the ERK signalling pathway in the stimulation of IL-8 production in epithelial cells by V. parahaemolyticus was established. Interestingly, TTSS2 inhibited IL-8 mRNA transcription at early stages of interaction between the bacterium and the cell. Conclusions This study demonstrated that V. parahaemolyticus activates the three major MAPK signalling pathways in intestinal epithelial cells in a TTSS1-dependent manner that involves the TTSS1 effector VP1680. Furthermore VP1680 and JNK and ERK activation were needed for maximal cytotoxicity of the bacterium. It was shown that V. parahaemolyticus is a strong inducer of IL-8 secretion and that induction reflects a balance between the effects of TTSS1 and TTSS2. Increases in IL-8 secretion were mediated by TTSS1 and VP1680, and augmented by ERK activation. These results shed light on the mechanisms of bacterial pathogenesis mediated by TTSS and suggest significant roles for MAPK signalling during infection with V. parahaemolyticus. PMID:21192810

  18. Comparison of molecular detection methods for Vibrio parahaemolyticus and Vibrio vulnificus.

    PubMed

    Jones, Jessica L; Hara-Kudo, Yukiko; Krantz, Jeffrey A; Benner, Ronald A; Smith, Amy B; Dambaugh, Timothy R; Bowers, John C; Depaola, Angelo

    2012-05-01

    Pathogenic vibrios are a global concern for seafood safety and many molecular methods have been developed for their detection. This study compares several molecular methods for detection of total and pathogenic Vibrio parahaemolyticus and Vibrio vulnificus, in MPN enrichments from oysters and fish intestine samples. This study employed the DuPont Qualicon BAX® System Real-Time PCR assay for detection of V. parahaemolyticus and V. vulnificus. Multiplex real-time PCR detection of total (tlh+), tdh+, and trh+V. parahaemolyticus was conducted on the Cepheid SmartCycler II. Total (rpoD) and tdh+V. parahaemolyticus were also detected using LAMP. V. vulnificus detection was performed using real-time PCR methods developed for the SmartCycler and the AB 7500 Fast. Recommended template preparations were compared to BAX® lysis samples for suitability. There was no significant difference in detection of V. parahaemolyticus and V. vulnificus using the BAX® or SmartCycler assays. The AB assay showed no difference from other methods in detection of V. vulnificus unless boiled templates were utilized. There was a significant difference in detection of tdh+V. parahaemolyticus between SmartCycler and LAMP assays unless the total (tlh+) V. parahaemolyticus gene target was omitted from the SmartCycler assay; a similar trend was observed for trh+V. parahaemolyticus. PMID:22265290

  19. Catechol Siderophore Transport by Vibrio cholerae

    PubMed Central

    Allred, Benjamin E.; Raymond, Kenneth N.; Payne, Shelley M.

    2015-01-01

    ABSTRACT Siderophores, small iron-binding molecules secreted by many microbial species, capture environmental iron for transport back into the cell. Vibrio cholerae synthesizes and uses the catechol siderophore vibriobactin and also uses siderophores secreted by other species, including enterobactin produced by Escherichia coli. E. coli secretes both canonical cyclic enterobactin and linear enterobactin derivatives likely derived from its cleavage by the enterobactin esterase Fes. We show here that V. cholerae does not use cyclic enterobactin but instead uses its linear derivatives. V. cholerae lacked both a receptor for efficient transport of cyclic enterobactin and enterobactin esterase to promote removal of iron from the ferrisiderophore complex. To further characterize the transport of catechol siderophores, we show that the linear enterobactin derivatives were transported into V. cholerae by either of the catechol siderophore receptors IrgA and VctA, which also transported the synthetic siderophore MECAM [1,3,5-N,N′,N″-tris-(2,3-dihydroxybenzoyl)-triaminomethylbenzene]. Vibriobactin is transported via the additional catechol siderophore receptor ViuA, while the Vibrio fluvialis siderophore fluvibactin was transported by all three catechol receptors. ViuB, a putative V. cholerae siderophore-interacting protein (SIP), functionally substituted for the E. coli ferric reductase YqjH, which promotes the release of iron from the siderophore in the bacterial cytoplasm. In V. cholerae, ViuB was required for the use of vibriobactin but was not required for the use of MECAM, fluvibactin, ferrichrome, or the linear derivatives of enterobactin. This suggests the presence of another protein in V. cholerae capable of promoting the release of iron from these siderophores. IMPORTANCE Vibrio cholerae is a major human pathogen and also serves as a model for the Vibrionaceae, which include other serious human and fish pathogens. The ability of these species to persist and acquire essential nutrients, including iron, in the environment is epidemiologically important but not well understood. In this work, we characterize the ability of V. cholerae to acquire iron by using siderophores produced by other organisms. We resolve confusion in the literature regarding its ability to use the Escherichia coli siderophore enterobactin and identify the receptor and TonB system used for the transport of several siderophores. The use of some siderophores did not require the ferric reductase ViuB, suggesting that an uncharacterized ferric reductase is present in V. cholerae. PMID:26100039

  20. Oligotyping reveals community level habitat selection within the genus Vibrio

    PubMed Central

    Schmidt, Victor T.; Reveillaud, Julie; Zettler, Erik; Mincer, Tracy J.; Murphy, Leslie; Amaral-Zettler, Linda A.

    2014-01-01

    The genus Vibrio is a metabolically diverse group of facultative anaerobic bacteria, common in aquatic environments and marine hosts. The genus contains several species of importance to human health and aquaculture, including the causative agents of human cholera and fish vibriosis. Vibrios display a wide variety of known life histories, from opportunistic pathogens to long-standing symbionts with individual host species. Studying Vibrio ecology has been challenging as individual species often display a wide range of habitat preferences, and groups of vibrios can act as socially cohesive groups. Although strong associations with salinity, temperature and other environmental variables have been established, the degree of habitat or host specificity at both the individual and community levels is unknown. Here we use oligotyping analyses in combination with a large collection of existing Vibrio 16S ribosomal RNA (rRNA) gene sequence data to reveal patterns of Vibrio ecology across a wide range of environmental, host, and abiotic substrate associated habitats. Our data show that individual taxa often display a wide range of habitat preferences yet tend to be highly abundant in either substrate-associated or free-living environments. Our analyses show that Vibrio communities share considerable overlap between two distinct hosts (i.e., sponge and fish), yet are distinct from the abiotic plastic substrates. Lastly, evidence for habitat specificity at the community level exists in some habitats, despite considerable stochasticity in others. In addition to providing insights into Vibrio ecology across a broad range of habitats, our study shows the utility of oligotyping as a facile, high-throughput and unbiased method for large-scale analyses of publically available sequence data repositories and suggests its wide application could greatly extend the range of possibilities to explore microbial ecology. PMID:25431569

  1. Vibrio cholerae Biofilms and Cholera Pathogenesis

    PubMed Central

    Silva, Anisia J.; Benitez, Jorge A.

    2016-01-01

    Vibrio cholerae can switch between motile and biofilm lifestyles. The last decades have been marked by a remarkable increase in our knowledge of the structure, regulation, and function of biofilms formed under laboratory conditions. Evidence has grown suggesting that V. cholerae can form biofilm-like aggregates during infection that could play a critical role in pathogenesis and disease transmission. However, the structure and regulation of biofilms formed during infection, as well as their role in intestinal colonization and virulence, remains poorly understood. Here, we review (i) the evidence for biofilm formation during infection, (ii) the coordinate regulation of biofilm and virulence gene expression, and (iii) the host signals that favor V. cholerae transitions between alternative lifestyles during intestinal colonization, and (iv) we discuss a model for the role of V. cholerae biofilms in pathogenicity. PMID:26845681

  2. Viscosity dictates metabolic activity of Vibrio ruber

    PubMed Central

    Bori?, Maja; Danev?i?, Tjaa; 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

  3. Vibrio cholerae: lessons for mucosal vaccine design

    PubMed Central

    Bishop, Anne L; Camilli, Andrew

    2011-01-01

    The ability of Vibrio cholerae to persist in bodies of water will continue to confound our ability to eradicate cholera through improvements to infrastructure, and thus cholera vaccines are needed. We aim for an inexpensive vaccine that can provide long-lasting protection from all epidemic cholera infections, currently caused by O1 or O139 serogroups. Recent insights into correlates of protection, epidemiology and pathogenesis may help us design improved vaccines. This notwithstanding, we have come to appreciate that even marginally protective vaccines, such as oral whole-cell killed vaccines, if widely distributed, can provide significant protection, owing to herd immunity. Further efforts are still required to provide more effective protection of young children. PMID:21162623

  4. Vibrio cholerae Biofilms and Cholera Pathogenesis.

    PubMed

    Silva, Anisia J; Benitez, Jorge A

    2016-02-01

    Vibrio cholerae can switch between motile and biofilm lifestyles. The last decades have been marked by a remarkable increase in our knowledge of the structure, regulation, and function of biofilms formed under laboratory conditions. Evidence has grown suggesting that V. cholerae can form biofilm-like aggregates during infection that could play a critical role in pathogenesis and disease transmission. However, the structure and regulation of biofilms formed during infection, as well as their role in intestinal colonization and virulence, remains poorly understood. Here, we review (i) the evidence for biofilm formation during infection, (ii) the coordinate regulation of biofilm and virulence gene expression, and (iii) the host signals that favor V. cholerae transitions between alternative lifestyles during intestinal colonization, and (iv) we discuss a model for the role of V. cholerae biofilms in pathogenicity. PMID:26845681

  5. Vibrio Vulnificus Necrotizing Fasciitis Associated with Acupuncture.

    PubMed

    Kotton, Yael; Soboh, Soboh; Bisharat, Naiel

    2015-08-11

    Necrotizing fasciitis is a severe life-threatening infection of the deep subcutaneous tissues and fascia. Infection with Vibrio vulnificus, a halophilic Gram-negative bacillus found worldwide in warm coastal waters, can lead to severe complications, particularly among patients with chronic liver diseases. We herein present an unusual case of necrotizing fasciitis caused by V. vulnificus triggered by acupuncture needle insertion. The patient, who suffered from diabetes mellitus and nonalcoholic fatty liver disease and worked at a fish hatchery, denied any injury prior to acupuncture. This is the first ever reported case of V. vulnificus infection triggered by acupuncture needle insertion, clearly emphasizing the potential hazards of the prolonged survival of V. vulnificus on the skin. The potential infectious complications of acupuncture needle insertion are discussed. PMID:26500738

  6. Vibrio Vulnificus Necrotizing Fasciitis Associated with Acupuncture

    PubMed Central

    Kotton, Yael; Soboh, Soboh; Bisharat, Naiel

    2015-01-01

    Necrotizing fasciitis is a severe life-threatening infection of the deep subcutaneous tissues and fascia. Infection with Vibrio vulnificus, a halophilic Gram-negative bacillus found worldwide in warm coastal waters, can lead to severe complications, particularly among patients with chronic liver diseases. We herein present an unusual case of necrotizing fasciitis caused by V. vulnificus triggered by acupuncture needle insertion. The patient, who suffered from diabetes mellitus and nonalcoholic fatty liver disease and worked at a fish hatchery, denied any injury prior to acupuncture. This is the first ever reported case of V. vulnificus infection triggered by acupuncture needle insertion, clearly emphasizing the potential hazards of the prolonged survival of V. vulnificus on the skin. The potential infectious complications of acupuncture needle insertion are discussed. PMID:26500738

  7. A chimeric siderophore halts swarming Vibrio.

    PubMed

    Bttcher, Thomas; Clardy, Jon

    2014-03-24

    Some bacteria swarm under some circumstances; they move rapidly and collectively over a surface. In an effort to understand the molecular signals controlling swarming, we isolated two bacterial strains from the same red seaweed, Vibrio alginolyticus B522, a vigorous swarmer, and Shewanella algae B516, which inhibits V.?alginolyticus swarming in its vicinity. Plate assays combined with NMR, MS, and X-ray diffraction analyses identified a small molecule, which was named avaroferrin, as a potent swarming inhibitor. Avaroferrin, a previously unreported cyclic dihydroxamate siderophore, is a chimera of two well-known siderophores: putrebactin and bisucaberin. The sequenced genome of S.?algae revealed avaroferrin's biosynthetic gene cluster to be a mashup of putrebactin and bisucaberin biosynthetic genes. Avaroferrin blocks swarming through its ability to bind iron in a form that cannot be pirated by V.?alginolyticus, thereby securing this essential resource for its producer. PMID:24615751

  8. A Chimeric Siderophore Halts Swarming Vibrio**

    PubMed Central

    Bttcher, Thomas; Clardy, Jon

    2014-01-01

    Some bacteria under some circumstances swarm; they move rapidly and collectively over a surface. In an effort to understand the molecular signals controlling swarming, we isolated two strains from the same red seaweed Vibrio alginolyticus B522, a vigorous swarmer, and Shewanella algae B516, which inhibits V. alginolyticus swarming in its vicinity. Plate assays combined with NMR, MS, and X-ray diffraction analyses identified a small molecule, which was named avaroferrin, as a potent swarming inhibitor. Avaroferrin, a previously unreported cyclic dihydroxamate siderophore, is a chimera of two well-known siderophores: putrebactin and bisucaberin. The sequenced genome of S. algae revealed avaroferrins biosynthetic gene cluster to be a mashup of putrebactin and bisucaberin biosynthetic genes. Avaroferrin blocks swarming through its ability to bind iron in a form that cannot be pirated by V. alginolyticus, thereby securing this essential resource for its producer. PMID:24615751

  9. Detection and Antimicrobial Resistance of Vibrio Isolates in Aquaculture Environments: Implications for Public Health.

    PubMed

    Igbinosa, Etinosa O

    2016-04-01

    The aim of this study was to evaluate the presence of Vibrio isolates recovered from four different fish pond facilities in Benin City, Nigeria, determine their antibiogram profiles, and evaluate the public health implications of these findings. Fish pond water samples were collected from four sampling sites between March and September 2014. A total of 56 samples were collected and screened for the isolation of Vibrio species using standard culture-based methods. Polymerase chain reaction (PCR) was used to confirm the identities of the Vibrio species using the genus-specific and species-specific primers. Vibrio species were detected at all the study sites at a concentration on the order of 10(3) and 10(6) CFU/100 ml. A total of 550 presumptive Vibrio isolates were subjected to PCR confirmation. Of these isolates, 334 isolates tested positive, giving an overall Vibrio prevalence rate of 60.7%. The speciation of the 334 Vibrio isolates from fish ponds yielded 32.63% Vibrio fluvialis, 20.65% Vibrio parahaemolyticus, 18.26% Vibrio vulnificus, and 28.44% other Vibrio species. In all, 167 confirmed Vibrio isolates were selected from a pool of 334 confirmed Vibrio isolates for antibiogram profiling. The susceptibility profiles of 20 antimicrobial agents on the isolates revealed a high level of resistance for AMP(R), ERY(R), NAL(R), SUL(R), TMP(R), SXT(R), TET(R), OTC(R), and CHL(R). The percentage of multiple drug resistance Vibrio isolates was 67.6%. The multiple antibiotic resistance index mean value of 0.365 for the Vibrio isolates found in this study indicated that the Vibrio isolates were exposed to high-risk sources of contamination when antibiotics were frequently used. The resistant Vibrio strains could be transmitted through the food chain to humans and therefore constitutes a risk to public health. PMID:26540391

  10. Two-component response regulators of Vibrio fischeri: identification, mutagenesis, and characterization.

    PubMed

    Hussa, Elizabeth A; O'Shea, Therese M; Darnell, Cynthia L; Ruby, Edward G; Visick, Karen L

    2007-08-01

    Two-component signal transduction systems are utilized by prokaryotic and eukaryotic cells to sense and respond to environmental stimuli, both to maintain homeostasis and to rapidly adapt to changing conditions. Studies have begun to emerge that utilize a large-scale mutagenesis approach to analyzing these systems in prokaryotic organisms. Due to the recent availability of its genome sequence, such a global approach is now possible for the marine bioluminescent bacterium Vibrio fischeri, which exists either in a free-living state or as a mutualistic symbiont within a host organism such as the Hawaiian squid species Euprymna scolopes. In this work, we identified 40 putative two-component response regulators encoded within the V. fischeri genome. Based on the type of effector domain present, we classified six as NarL type, 13 as OmpR type, and six as NtrC type; the remaining 15 lacked a predicted DNA-binding domain. We subsequently mutated 35 of these genes via a vector integration approach and analyzed the resulting mutants for roles in bioluminescence, motility, and competitive colonization of squid. Through these assays, we identified three novel regulators of V. fischeri luminescence and seven regulators that altered motility. Furthermore, we found 11 regulators with a previously undescribed effect on competitive colonization of the host squid. Interestingly, five of the newly characterized regulators each affected two or more of the phenotypes examined, strongly suggesting interconnectivity among systems. This work represents the first large-scale mutagenesis of a class of genes in V. fischeri using a genomic approach and emphasizes the importance of two-component signal transduction in bacterium-host interactions. PMID:17586650

  11. The Regulatory Network of Natural Competence and Transformation of Vibrio cholerae

    PubMed Central

    Lo Scrudato, Mirella; Blokesch, Melanie

    2012-01-01

    The human pathogen Vibrio cholerae is an aquatic bacterium frequently encountered in rivers, lakes, estuaries, and coastal regions. Within these environmental reservoirs, the bacterium is often found associated with zooplankton and more specifically with their chitinous exoskeleton. Upon growth on such chitinous surfaces, V. cholerae initiates a developmental program termed “natural competence for genetic transformation.” Natural competence for transformation is a mode of horizontal gene transfer in bacteria and contributes to the maintenance and evolution of bacterial genomes. In this study, we investigated competence gene expression within this organism at the single cell level. We provide evidence that under homogeneous inducing conditions the majority of the cells express competence genes. A more heterogeneous expression pattern was observable on chitin surfaces. We hypothesize that this was the case due to the heterogeneity around the chitin surface, which might vary extensively with respect to chitin degradation products and autoinducers; these molecules contribute to competence induction based on carbon catabolite repression and quorum-sensing pathways, respectively. Therefore, we investigated the contribution of these two signaling pathways to natural competence in detail using natural transformation assays, transcriptional reporter fusions, quantitative RT–PCR, and immunological detection of protein levels using Western blot analysis. The results illustrate that all tested competence genes are dependent on the transformation regulator TfoX. Furthermore, intracellular cAMP levels play a major role in natural transformation. Finally, we demonstrate that only a minority of genes involved in natural transformation are regulated in a quorum-sensing-dependent manner and that these genes determine the fate of the surrounding DNA. We conclude with a model of the regulatory circuit of chitin-induced natural competence in V. cholerae. PMID:22737089

  12. 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

  13. 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

  14. Two replication regions in the pJM1 virulence plasmid of the marine pathogen Vibrio anguillarum.

    PubMed

    Naka, Hiroaki; Chen, Qian; Mitoma, Yasutami; Nakamura, Yusuke; McIntosh-Tolle, Daniel; Gammie, Alison E; Tolmasky, Marcelo E; Crosa, Jorge H

    2012-03-01

    Vibrio anguillarum is a fish pathogen that causes vibriosis, a serious hemorrhagic septicemia, in wild and cultured fish. Many serotype O1 strains of this bacterium harbor the 65kb plasmid pJM1 carrying the majority of genes encoding the siderophore anguibactin iron transport system that is one of the most important virulence factors of this bacterium. We previously identified a replication region of the pJM1 plasmid named ori1. In this work we determined that ori1 can replicate in Escherichia coli and that the chromosome-encoded proteins DnaB, DnaC and DnaG are essential for its replication whereas PolI, IHF and DnaA are not required. The copy number of the pJM1 plasmid is 1-2, albeit cloned smaller fragments of the ori1 region replicate with higher copy numbers in V. anguillarum while in E. coli we did not observe an obvious difference of the copy numbers of these constructs which were all high. Furthermore, we were able to delete the ori1 region from the pJM1 plasmid and identified a second replication region in pJM1 that we named ori2. This second replication region is located on ORF25 that is within the trans-acting factor (TAFr) region, and showed that it can only replicate in V. anguillarum. PMID:22239981

  15. Two replication regions in the pJM1 virulence plasmid of the marine pathogen Vibrio anguillarum

    PubMed Central

    Naka, Hiroaki; Chen, Qian; Mitoma, Yasutami; Nakamura, Yusuke; McIntosh-Tolle, Daniel; Gammie, Alison E.; Tolmasky, Marcelo E.; Crosa, Jorge H.

    2012-01-01

    Vibrio anguillarum is a fish pathogen that causes vibriosis, a serious hemorrhagic septicemia, in wild and cultured fish. Many serotype O1 strains of this bacterium harbor the 65kb plasmid pJM1 carrying the majority of genes encoding the siderophore anguibactin iron transport system that is one of the most important virulence factors of this bacterium. We previously identified a replication region of the pJM1 plasmid named ori1. In this work we determined that ori1 can replicate in E. coli and that the chromosome-encoded proteins DnaB, DnaC and DnaG are essential for its replication whereas PolI, IHF and DnaA are not required. The copy number of the pJM1 plasmid is 12, albeit cloned smaller fragments of the ori1 region replicate with higher copy numbers in V. anguillarum while in E. coli we did not observe an obvious difference of the copy numbers of these constructs which were all high. Furthermore, we were able to delete the ori1 region from the pJM1 plasmid and identified a second replication region in pJM1 that we named ori2. This second replication region is located on ORF25 that is within the trans-acting factor (TAFr) region, and showed that it can only replicate in V. anguillarum. PMID:22239981

  16. 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

  17. 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

  18. Identification of a Novel Matrix Protein That Promotes Biofilm Maturation in Vibrio fischeri

    PubMed Central

    Ray, Valerie A.; Driks, Adam

    2014-01-01

    Bacteria form communities, termed biofilms, in which cells adhere to each other within a matrix, typically comprised of polysaccharides, proteins, and extracellular DNA. Biofilm formation by the marine bacterium Vibrio fischeri requires the Syp polysaccharide, but the involvement of matrix proteins is as yet unknown. Here we identified three genes, termed bmpA, -B, and -C (biofilm maturation protein), with overlapping functions in biofilm maturation. A triple bmpABC mutant, but not single or double mutants, was defective in producing wrinkled colonies, a form of biofilm. Surprisingly, the triple mutant was competent to form pellicles, another biofilm phenotype, but they generally lacked a three-dimensional architecture. Transmission electron microscopy revealed that the extracellular matrix of the bmp mutant contained electron-dense, thread-like structures that were also present in the wild type but lacking in syp mutant strains. We hypothesized that the bmp mutant produces the Syp polysaccharide but fails to produce/export a distinct matrix component. Indeed, a mixture of the bmp and syp mutants produced a wrinkled colony. Finally, BmpA could be detected in cell-free supernatants from disrupted pellicles. Thus, this work identifies a new matrix protein necessary for biofilm maturation by V. fischeri and, based on the conservation of bmp, potentially other microbes. PMID:25404700

  19. Vibrio parahaemolyticus thermostable direct hemolysin modulates cytoskeletal organization and calcium homeostasis in intestinal cultured cells.

    PubMed

    Fabbri, A; Falzano, L; Frank, C; Donelli, G; Matarrese, P; Raimondi, F; Fasano, A; Fiorentini, C

    1999-03-01

    Vibrio parahaemolyticus is a marine bacterium known to be the leading cause of seafood gastroenteritis worldwide. A 46-kDa homodimer protein secreted by this microorganism, the thermostable direct hemolysin (TDH), is considered a major virulence factor involved in bacterial pathogenesis since a high percentage of strains of clinical origin are positive for TDH production. TDH is a pore-forming toxin, and its most extensively studied effect is the ability to cause hemolysis of erythrocytes from different mammalian species. Moreover, TDH induces in a variety of cells cytotoxic effects consisting mainly of cell degeneration which often leads to loss of viability. In this work, we examined the cellular changes induced by TDH in monolayers of IEC-6 cells (derived from the rat crypt small intestine), which represent a useful cell model for studying toxins from enteric bacteria. In experimental conditions allowing cell survival, TDH induces a rapid transient increase in intracellular calcium as well as a significant though reversible decreased rate of progression through the cell cycle. The morphological changes seem to be dependent on the organization of the microtubular network, which appears to be the preferential cytoskeletal element involved in the cellular response to the toxin. PMID:10024554

  20. Enterotoxicity and cytotoxicity of Vibrio parahaemolyticus thermostable direct hemolysin in in vitro systems.

    PubMed

    Raimondi, F; Kao, J P; Fiorentini, C; Fabbri, A; Donelli, G; Gasparini, N; Rubino, A; Fasano, A

    2000-06-01

    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 cytotoxic effects by using both human and rat cell monolayers. As revealed by microspectrofluorimetry, the toxin causes a dose-dependent increase in intracellular free calcium in both Caco-2 and IEC-6 cells. This effect was reversible only when low toxin concentrations were tested. The TDH-activated ion influx pathway is not selective for calcium but admits ions such sodium and manganese as well. Furthermore, in the same range of concentration, the hemolysin triggers a calcium-dependent chloride secretion. At high concentrations, TDH induces a dose-dependent but calcium-independent cell death as assessed by functional, biochemical, and morphological assays. PMID:10816461

  1. The Vibrio Cholerae Type VI Secretion System: Evaluating its Role in the Human Disease Cholera.

    PubMed

    Miyata, Sarah T; Kitaoka, Maya; Wieteska, Lukasz; Frech, Christian; Chen, Nansheng; Pukatzki, Stefan

    2010-01-01

    Vibrio cholerae, the marine bacterium responsible for the diarrheal disease cholera, utilizes a multitude of virulence factors to cause disease. The importance of two of these factors, the toxin co-regulated pilus (TCP) and cholera toxin (CT), has been well documented for pandemic O1 and epidemic O139 serogroups. In contrast, endemic non-O1 and non-O139 serogroups can cause localized outbreaks of cholera-like illness, often in the absence of TCP and CT. One virulence mechanism used by these strains is the type VI secretion system (T6SS) to export toxins across the cell envelope and confer toxicity toward eukaryotic and prokaryotic organisms. The V. cholerae strain V52 (an O37 serogroup strain) possesses a constitutively active T6SS and was responsible for an outbreak of gastroenteritis in Sudan in 1968. To evaluate a potential role of the T6SS in the disease cholera, we compared the T6SS clusters of V. cholerae strains with sequenced genomes. We found that the majority of V. cholerae strains, including one pandemic strain, contain intact T6SS gene clusters; thus, we propose that the T6SS is a conserved mechanism that allows pandemic and endemic V. cholerae to persist both in the host and in the environment. PMID:21607085

  2. Purification and characterization of L-asparaginase with anti-lymphoma activity from Vibrio succinogenes.

    PubMed

    Distasio, J A; Niederman, R A; Kafkewitz, D; Goodman, D

    1976-11-25

    Homogeneols L-asparaginase with anti-lymphoma activity was prepared from Vibrio succinogenes, an anaerobic bacterium from the bovine rumen. An overall yield of pure L-asparaginase of 40 to 45% and a specific activity of 200 +/- 2 IU per mg of protein was obtained. The pure enzyme can be stored at -20 degrees for at least 3 months with no loss of activity. The isoelectric point of the L-asparaginase is 8.74. No carbohydrate, phosphorus, tryptophan, disulfide, or sulfhydryl groups were detected. The enzyme has a molecular weight of 146,000 and a subunit weight of approximately 37,000. The Km of the enzyme for L-asparagine is 4.78 X 10(-5) M and the pH optimum of the L-asparaginase reaction is 7.3. D-Asparagine was hydrolyzed at 6.5% of the rate found with the L isomer. L-Glutamine and a variety of other amides were not hydrolyzed at significant rates; the activity of the enzyme for L-glutamine was 130- to 600-fold less than that of other therapeutically effective L-asparaginases of bacterial origin. The L-asparaginase from V. succinogenes is immunologically distinct from the L-asparaginase (EC-2) of Escherichia coli. PMID:11211

  3. Visualization of coral host-pathogen interactions using a stable GFP-labeled Vibrio coralliilyticus strain

    NASA Astrophysics Data System (ADS)

    Pollock, F. Joseph; Krediet, Cory J.; Garren, Melissa; Stocker, Roman; Winn, Karina; Wilson, Bryan; Huete-Stauffer, Carla; Willis, Bette L.; Bourne, David G.

    2015-06-01

    The bacterium Vibrio coralliilyticus has been implicated as the causative agent of coral tissue loss diseases (collectively known as white syndromes) at sites across the Indo-Pacific and represents an emerging model pathogen for understanding the mechanisms linking bacterial infection and coral disease. In this study, we used a mini-Tn7 transposon delivery system to chromosomally label a strain of V. coralliilyticus isolated from a white syndrome disease lesion with a green fluorescent protein gene (GFP). We then tested the utility of this modified strain as a research tool for studies of coral host-pathogen interactions. A suite of biochemical assays and experimental infection trials in a range of model organisms confirmed that insertion of the GFP gene did not interfere with the labeled strain's virulence. Using epifluorescence video microscopy, the GFP-labeled strain could be reliably distinguished from non-labeled bacteria present in the coral holobiont, and the pathogen's interactions with the coral host could be visualized in real time. This study demonstrates that chromosomal GFP labeling is a useful technique for visualization and tracking of coral pathogens and provides a novel tool to investigate the role of V. coralliilyticus in coral disease pathogenesis.

  4. Comparative toxic effects of formulated simazine on Vibrio fischeri and gilthead seabream (Sparus aurata L.) larvae.

    PubMed

    Arufe, M I; Arellano, J; Moreno, M J; Sarasquete, C

    2004-12-01

    The use of Early Life Stage (ELS) tests is a useful tool in risk assessment. The purpose of this study was to compare the sensitivity of the seabream (Sparus aurata) larvae with the extensively used Microtox test on a commercial formulation containing simazine, an s-triazine herbicide. To this end, survival, growth and histopathological changes displayed by seabream yolk sac larvae exposed during 72 h post-hatching to nominal concentrations of the commercial preparation up to its saturating concentration in water, and bioluminescence of the marine bacteria Vibrio fischeri (Microtox) were studied. Survival of larvae after three days of exposure was significantly reduced in the highest (4.5 mg/l) concentration, but no effects on growth were found in any of the simazine treatments. The 72 h LC50 value for yolk sac larvae was estimated as 4.19 mg/l. Commercial grade simazine did not exert any significant toxicity to the marine bacterium V. fischeri at the concentrations tested. PMID:15519419

  5. 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. PMID:25852665

  6. 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

  7. 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

  8. Vibrio cholerae phosphatases required for the utilization of nucleotides and extracellular DNA as phosphate sources.

    PubMed

    McDonough, EmilyKate; Kamp, Heather; Camilli, Andrew

    2016-02-01

    Phosphate is essential for life, being used in many core processes such as signal transduction and synthesis of nucleic acids. The waterborne agent of cholera, Vibrio cholerae, encounters phosphate limitation in both the aquatic environment and human intestinal tract. This bacterium can utilize extracellular DNA (eDNA) as a phosphate source, a phenotype dependent on secreted endo- and exonucleases. However, no transporter of nucleotides has been identified in V.?cholerae, suggesting that in order for the organism to utilize the DNA as a phosphate source, it must first separate the phosphate and nucleoside groups before transporting phosphate into the cell. In this study, we investigated the factors required for assimilation of phosphate from eDNA. We identified PhoX, and the previously unknown proteins UshA and CpdB as the major phosphatases that allow phosphate acquisition from eDNA and nucleotides. We demonstrated separable but partially overlapping roles for the three phosphatases and showed that the activity of PhoX and CpdB is induced by phosphate limitation. Thus, this study provides mechanistic insight into how V.?cholerae can acquire phosphate from extracellular DNA, which is likely to be an important phosphate source in the environment and during infection. PMID:26175126

  9. Non-coding sRNAs regulate virulence in the bacterial pathogen Vibrio cholerae

    PubMed Central

    Bardill, J. Patrick; Hammer, Brian

    2012-01-01

    Vibrio cholerae is the waterborne bacterium responsible for worldwide outbreaks of the acute, potentially fatal cholera diarrhea. The primary factors this human pathogen uses to cause the disease are controlled by a complex regulatory program linking extracellular signaling inputs to changes in expression of several critical virulence genes. Recently it has been uncovered that many non-coding regulatory sRNAs are important components of the V. cholerae virulence regulon. Most of these sRNAs appear to require the RNA-binding protein, Hfq, to interact with and alter the expression of target genes, while a few sRNAs appear to function by an Hfq-independent mechanism. Direct base-pairing between the sRNAs and putative target mRNAs has been shown in a few cases but the extent of each sRNAs regulon is not fully known. Genetic and biochemical methods, coupled with computational and genomics approaches, are being used to validate known sRNAs and also to identify many additional putative sRNAs that may play a role in the pathogenic lifestyle of V. cholerae. PMID:22546941

  10. Vibrio tapetis, the Causative Agent of Brown Ring Disease, Forms Biofilms with Spherical Components

    PubMed Central

    Rodrigues, Sophie; Paillard, Christine; Le Pennec, Gaël; Dufour, Alain; Bazire, Alexis

    2015-01-01

    Vibrio tapetis is a marine bacterium causing Brown Ring Disease (BRD) in the Manila clam Ruditapes philippinarum. V. tapetis biofilm formation remains unexplored depite the fact that it might be linked to pathogenicity. Our objectives were to characterize the in vitro biofilm formation of V. tapetis and evaluate the effects of culture conditions. Biofilm structure and its matrix composition were examined by confocal laser scanning microscopy and scanning electron microscopy. V. tapetis was able to form biofilms on a glass substratum within 24 h. Polysaccharides and extracellular DNA of the biofilm matrixes were differently distributed depending on the V. tapetis strains. Spherical components of about 1–2 μm diameter were found at the biofilm surface. They contain DNA, proteins, and seemed to be physically linked to bacteria and of cellular nature. Transmission electron microscopy showed that the spherical components were devoid of internal compartments. Temperatures >21°C inhibit BRD whereas low salinity (2%) favor it, none of the both conditions altered V. tapetis' ability to form biofilms in vitro. We suggest therefore that biofilm formation could play a role in the persistence of the pathogen in clam than in BRD symptoms. PMID:26696991

  11. Bioluminescence of Vibrio fischeri in continuous culture: optimal conditions for stability and intensity of photoemission.

    PubMed

    Scheerer, Stefanie; Gomez, Francisco; Lloyd, David

    2006-11-01

    Continuous cultivation of the bioluminescent bacterium, Vibrio fischeri NRRL-B-11177, in a fermenter provided a constant supply of bacteria in exponential growth phase. These bacteria may be used as stable bioindicators to measure perturbation of the metabolic state by physical and chemical agents. However, optimization of light emission necessitates careful choice of growth medium and culture operating conditions. Optimized conditions that supported long-term cultivation of V. fischeri NRRL-B-11177 with stable intense bioluminescence were: a dilution rate of 0.08-0.09h(-1), air supply of 600mlmin(-1), stirring of 300-350rpm at a constant incubation temperature within the range of 20 to 26 degrees C and pH7.8. These conditions were as successful in a 500-ml as in a 10-ml fermenter. This system provided a reliable long-term (more than 1 month) continuous culture facility for the reproducible measurement of perturbation of V. fischeri by monitoring changes in luminescence. PMID:16750278

  12. Optimization and characterization of biosurfactant production from marine Vibrio sp. strain 3B-2

    PubMed Central

    Hu, Xiaoke; Wang, Caixia; Wang, Peng

    2015-01-01

    A biosurfactant-producing bacterium, designated 3B-2, was isolated from marine sediment and identified as Vibrio sp. by 16S rRNA gene sequencing. The culture medium composition was optimized to increase the capability of 3B-2 for producing biosurfactant. The produced biosurfactant was characterized in terms of protein concentration, surface tension, and oil-displacement efficiency. The optimal medium for biosurfactant production contained: 0.5% lactose, 1.1% yeast extract, 2% sodium chloride, and 0.1% disodium hydrogen phosphate. Under optimal conditions (28°C), the surface tension of crude biosurfactant could be reduced to 41 from 71.5 mN/m (water), while its protein concentration was increased to up to 6.5 g/L and the oil displacement efficiency was improved dramatically at 6.5 cm. Two glycoprotein fractions with the molecular masses of 22 and 40 kDa were purified from the biosurfactant, which held great potential for applications in microbial enhanced oil recovery and bioremediation. PMID:26441908

  13. Genotyping of virulence plasmid from Vibrio parahaemolyticus isolates causing acute hepatopancreatic necrosis disease in shrimp.

    PubMed

    Han, Jee Eun; Tang, Kathy F J; Lightner, Donald V

    2015-08-20

    Acute hepatopancreatic necrosis disease (AHPND) has caused severe mortalities in farmed penaeid shrimp throughout SE Asia and Mexico. The causative agent of AHPND is the marine bacterium Vibrio parahaemolyticus, which secretes PirA- and PirB-like binary toxin that caused deterioration in the hepatopancreas of infected shrimp. The genes responsible for the production of this toxin are located in a large plasmid residing within the bacterial cells. We analyzed the plasmid sequence from the whole genome sequences of AHPND-V. parahaemolyticus isolates and identified 2 regions that exhibit a clear geographical variation: a 4243-bp Tn3-like transposon and a 9-bp small sequence repeat (SSR). The Tn3-like transposon was only found in the isolates from Mexico and 2 unspecified Central American countries, but not in SE Asian isolates from China, Vietnam, and Thailand. We developed PCR methods to characterize AHPND-V. parahaemolyticus isolates as either Mexican-type or SE Asian-type based on the presence of the Tn3-like transposon. The SSR is found within the coding region of a hypothetical protein and has either 4, 5, or 6 repeat units. SSRs with 4 repeat units were found in isolates from Vietnam, China, and Thailand. SSRs with 5 repeat units were found in some Vietnamese isolates, and SSRs with 6 repeat units were only found in the Mexican isolates. PMID:26290509

  14. Characterization of the Vibrio fischeri Fatty Acid Chemoreceptors, VfcB and VfcB2.

    PubMed

    Nikolakakis, K; Monfils, K; Moriano-Gutierrez, S; Brennan, C A; Ruby, E G

    2015-01-01

    Bacteria use a wide variety of methyl-accepting chemotaxis proteins (MCPs) to mediate their attraction to or repulsion from different chemical signals in their environment. The bioluminescent marine bacterium Vibrio fischeri is the monospecific symbiont of the Hawaiian bobtail squid, Euprymna scolopes, and encodes a large repertoire of MCPs that are hypothesized to be used during different parts of its complex, multistage lifestyle. Here, we report the initial characterization of two such MCPs from V. fischeri that are responsible for mediating migration toward short- and medium-chain aliphatic (or fatty) acids. These receptors appear to be distributed among only members of the family Vibrionaceae and are likely descended from a receptor that has been lost by the majority of the members of this family. While chemotaxis greatly enhances the efficiency of host colonization by V. fischeri, fatty acids do not appear to be used as a chemical cue during this stage of the symbiosis. This study presents an example of straight-chain fatty acid chemoattraction and contributes to the growing body of characterized MCP-ligand interactions. PMID:26567312

  15. Fluid accumulation in infant mice caused by Vibrio hollisae and its extracellular enterotoxin.

    PubMed Central

    Kothary, M H; Richardson, S H

    1987-01-01

    Vibrio hollisae, a halophilic bacterium isolated from patients with diarrhea, was examined for virulence factor production. Intragastric administration of 2 X 10(7) CFU per mouse elicited fluid accumulation which peaked at ca. 6 h postchallenge in infant mice. An enterotoxin which elongated Chinese hamster ovary (CHO) cells was detected in extracts of infected-mouse intestines and in culture fluids from various growth media. The yield of the enterotoxin was maximal beginning at the onset of the stationary phase of growth in heart infusion broth supplemented with 0.5% NaCl. A concentrated preparation obtained by ammonium sulfate precipitation of culture supernatant fluids induced intestinal fluid accumulation which peaked at 2 h postchallenge in infant mice. The abilities of the enterotoxin preparation to elongate CHO cells and to elicit fluid accumulation in infant mice were inseparable by gel filtration, isoelectric focusing, and hydrophobic interaction chromatography. The enterotoxin has a molecular weight of ca. 33,000 by gel filtration and an isoelectric point of ca. 4 and is sensitive to heat. PMID:3818087

  16. The structure of a GFP-based antibody (fluorobody) to TLH, a toxin from Vibrio parahaemolyticus.

    PubMed

    Chen, Yaoguang; Huang, Xiaocheng; Wang, Rongzhi; Wang, Shihua; Shi, Ning

    2015-07-01

    A fluorobody is a manmade hybrid molecule that is composed of green fluorescent protein (GFP) and a fragment of antibody, which combines the affinity and specificity of an antibody with the visibility of a GFP. It is able to provide a real-time indication of binding while avoiding the use of tags and secondary binding reagents. Here, the expression, purification and crystal structure of a recombinant fluorobody for TLH (thermolabile haemolysin), a toxin from the lethal food-borne disease bacterium Vibrio parahaemolyticus, are presented. This is the first structure of a fluorobody to be reported. Crystals belonging to space group P4(3)2(1)2, with unit-cell parameters a = b = 63.35, c = 125.90 Å, were obtained by vapour diffusion in hanging drops and the structure was refined to an Rfree of 16.7% at 1.5 Å resolution. The structure shows a CDR loop of the antibody on the GFP scaffold. PMID:26144238

  17. The Makes Caterpillars Floppy (MCF)-Like Domain of Vibrio vulnificus Induces Mitochondrion-Mediated Apoptosis.

    PubMed

    Agarwal, Shivangi; Zhu, Yeuming; Gius, David R; Satchell, Karla J F

    2015-11-01

    The multifunctional-autoprocessing repeats-in-toxin (MARTXVv) toxin of Vibrio vulnificus plays a significant role in the pathogenesis of this bacterium through delivery of up to five effector domains to the host cells. Previous studies have established that the MARTXVv toxin is linked to V. vulnificus dependent induction of apoptosis, but the region of the large multifunction protein essential for this activity was not previously identified. Recently, we showed that the Makes Caterpillar Floppy-like MARTX effector domain (MCFVv) is an autoproteolytic cysteine protease that induces rounding of various cell types. In this study, we demonstrate that cell rounding induced by MCFVv is coupled to reduced metabolic rate and inhibition of cellular proliferation. Moreover, delivery of MCFVv into host cells either as a fusion to the N-terminal fragment of anthrax toxin lethal factor or when naturally delivered as a V. vulnificus MARTX toxin led to loss of mitochondrial membrane potential, release of cytochrome c, activation of Bax and Bak, and processing of caspases and poly-(ADP-ribose) polymerase (PARP-γ). These studies specifically link the MCFVv effector domain to induction of the intrinsic apoptosis pathway by V. vulnificus. PMID:26351282

  18. Quorum-sensing autoinducers resuscitate dormant Vibrio cholerae in environmental water samples

    PubMed Central

    Bari, S. M. Nayeemul; Roky, M. Kamruzzaman; Mohiuddin, M.; Kamruzzaman, M.; Mekalanos, John J.; Faruque, Shah M.

    2013-01-01

    Cholera epidemics have long been known to spread through water contaminated with human fecal material containing the toxigenic bacterium Vibrio cholerae. However, detection of V. cholerae in water is complicated by the existence of a dormant state in which the organism remains viable, but resists cultivation on routine bacteriological media. Growth in the mammalian intestine has been reported to trigger “resuscitation” of such dormant cells, and these studies have prompted the search for resuscitation factors. Although some positive reports have emerged from these investigations, the precise molecular signals that activate dormant V. cholerae have remained elusive. Quorum-sensing autoinducers are small molecules that ordinarily regulate bacterial gene expression in response to cell density or interspecies bacterial interactions. We have found that isolation of pathogenic clones of V. cholerae from surface waters in Bangladesh is dramatically improved by using enrichment media containing autoinducers either expressed from cloned synthase genes or prepared by chemical synthesis. These results may contribute to averting future disasters by providing a strategy for early detection of V. cholerae in surface waters that have been contaminated with the stools of cholera patients or asymptomatic infected human carriers. PMID:23716683

  19. Studies on diseased freshwater prawn Macrobrachium rosenbergii infected with Vibrio vulnificus.

    PubMed

    Sharshar, Kh M; Azab, E A

    2008-09-01

    The present study was aimed at isolation and characterization of the pathogenic bacterium from diseased freshwater prawn. The effect of the bacterial pathogen on hepatopancreas, gills and exoskeleton was also investigated. Diseased freshwater prawn, Macrobrachium rosenbergii were collected from commercial hatchery in Behera Governorate, Egypt. The diseased prawn showed dark brown focal lesions and necrosis of appendage tips. The causative bacterial pathogen was isolated from haemolymph and hepatopancreas of the diseased prawn. Based on the morphological, biochemical and physiological characteristics, in addition EPI 20E test, the isolated pathogen was characterized as Vibrio vulnificus. Histopathology, hepatopancreas showed haemocytic infiltration in the interstitial sinuses, thickening and ruptures of the basal lamina and necrosis of its tubules. Similarly, the accumulation of haemocytes in the haemocoelic space, swelling, fusion of lamellae and abnormal gill tips. Also, the cuticular layers of the exoskeleton of diseased prawn had a rough or wrinkled surface and were disrupted and separated from the epidermis. The pathogen, V. vulnificus showed different degrees of sensitivity to different antimicrobial agents. It was highly sensitive to each of the antibiotics rifadin, virbamycin, oflaxcin, garamycin, flummox and trimethoprim/sulfamethoxzole) and resistant to nalidixic acid, unasyn, velosef, claforan, negram and amoxicillin. The minimal inhibitory concentration of trimethoprin/sulfamethoxzole for the studied pathogen, V. vulnificus was 0.31/5.93 microg. PMID:19266922

  20. Occurrence of potentially pathogenic vibrios and related environmental factors in Songkhla Lake, Thailand.

    PubMed

    Thongchankaew, Uraiwan; Mittraparp-arthorn, Pimonsri; Sukhumungoon, Pharanai; Tansila, Natta; Nuidate, Taiyeebah; Nishibuchi, Mitsuaki; Vuddhakul, Varaporn

    2011-11-01

    Vibrios are halophilic bacteria that are ubiquitous in marine environments. Their occurrence in tropical lakes has rarely been investigated. In this study, the predominance and diversity of Vibrio spp. was investigated over a 12-month period in a coastal lagoon, Songkhla Lake, in southern Thailand. Water samples were collected at 2 stations in the estuary near Yor Island in Songkhla Lake. The predominant vibrios were detected by a culture-based method, using thiosulfate-citrate-bile salt-sucrose agar and CHROMagar Vibrio. The diversity of Vibrio spp. was evaluated using denaturant density gradient electrophoresis (DGGE). The highest numbers of total vibrios and Vibrio parahaemolyticus in both areas were observed during the summer. There was no significant correlation between the numbers of vibrios, including V. parahaemolyticus, and either the water temperature or plankton density. Variations in Vibrio species were observed with changes in salinity. Vibrio parahaemolyticus and V. cholerae non-O1/non-O139 were detected during the rainy season when the salinity dropped to nearly 0 parts per thousand. In both areas, V. alginolyticus was the most prominent species detected by the culture method, whereas Vibrio parahaemolyticus was detected by DGGE, every month. Other Vibrio spp. of potential public health concern were also detected by the culture method; they included V. vulnificus , V. fluvialis , and V. mimicus . PMID:22014235

  1. Novel Waddlia Intracellular Bacterium in Artibeus intermedius Fruit Bats, Mexico.

    PubMed

    Pierl, Sebastin Aguilar; Morales, Cirani Obregn; Martnez, Leonardo Perea; Ceballos, Nidia Archiga; Rivero, Juan Jos Prez; Daz, Osvaldo Lpez; Brayton, Kelly A; Setin, Alvaro Aguilar

    2015-12-01

    An intracellular bacterium was isolated from fruit bats (Artibeus intermedius) in Cocoyoc, Mexico. The bacterium caused severe lesions in the lungs and spleens of bats and intracytoplasmic vacuoles in cell cultures. Sequence analyses showed it is related to Waddlia spp. (order Chlamydiales). We propose to call this bacterium Waddlia cocoyoc. PMID:26583968

  2. Novel Waddlia Intracellular Bacterium in Artibeus intermedius Fruit Bats, Mexico

    PubMed Central

    Pierlé, Sebastián Aguilar; Morales, Cirani Obregón; Martínez, Leonardo Perea; Ceballos, Nidia Aréchiga; Rivero, Juan José Pérez; Díaz, Osvaldo López; Brayton, Kelly A.

    2015-01-01

    An intracellular bacterium was isolated from fruit bats (Artibeus intermedius) in Cocoyoc, Mexico. The bacterium caused severe lesions in the lungs and spleens of bats and intracytoplasmic vacuoles in cell cultures. Sequence analyses showed it is related to Waddlia spp. (order Chlamydiales). We propose to call this bacterium Waddlia cocoyoc. PMID:26583968

  3. An insight of traditional plasmid curing in Vibrio species.

    PubMed

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

    2015-01-01

    As the causative agent of foodborne related illness, Vibrio species causes a huge impact on the public health and management. Vibrio species is often associated with seafood as the latter plays a role as a vehicle to transmit bacterial infections. Hence, antibiotics are used not to promote growth but rather to prevent and treat bacterial infections. The extensive use of antibiotics in the aquaculture industry and environment has led to the emerging of antibiotic resistant strains. This phenomenon has triggered an alarming public health concern due to the increase number of pathogenic Vibrio strains that are resistant to clinically used antibiotics and is found in the environment. Antibiotic resistance and the genes location in the strains can be detected through plasmid curing assay. The results derived from plasmid curing assay is fast, cost effective, sufficient in providing insights, and influence the antibiotic management policies in the aquaculture industry. This presentation aims in discussing and providing insights on various curing agents in Vibrio species. To our best of knowledge, this is a first review written discussing on plasmid curing in Vibrio species. PMID:26347714

  4. 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

  5. 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

  6. Edema and hemoconcentration in mice experimentally infected with Vibrio vulnificus.

    PubMed Central

    Bowdre, J H; Poole, M D; Oliver, J D

    1981-01-01

    Vibrio vulnificus (lactose-positive Vibrio), a recently recognized pathogenic marine species, produced extreme hemoconcentration and death within 3 to 6 h after subcutaneous or intraperitoneal injection of 10(8) viable cells into mice; hemotocrit values approached 70% (normal, 45%). About 1 ml of edema fluid accumulated at the site of each subcutaneous injection, and locally increased vascular permeability was demonstrated by a skin bluing assay, using Evans blue dye. A corresponding fluid accumulation did not occur in the peritoneal cavity after an intraperitoneal injection. Filter-sterilized supernatants of cultures grown under a variety of conditions did not produce local edema or lethality, nor did whole Vibrio cells killed by a variety of methods or disrupted by sonic oscillation. Edema fluids collected from infected mice and sterilized by filtration had no effect when they were injected subcutaneously or intraperitoneally into mice. Inocula of 10(9) viable cells of V. vulnificus contained within a diffusion chamber implanted subcutaneously did not produce skin bluing, edema, or lethality; Vibrio cells remained viable and virulent within these chambers for at least 2 weeks. These experiments suggested that vascular permeability changes in V. vulnificus infections may not be attributable to a diffusible toxin and may require direct contact between host cells and viable Vibrio cells. PMID:7251164

  7. An insight of traditional plasmid curing in Vibrio species

    PubMed Central

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

    2015-01-01

    As the causative agent of foodborne related illness, Vibrio species causes a huge impact on the public health and management. Vibrio species is often associated with seafood as the latter plays a role as a vehicle to transmit bacterial infections. Hence, antibiotics are used not to promote growth but rather to prevent and treat bacterial infections. The extensive use of antibiotics in the aquaculture industry and environment has led to the emerging of antibiotic resistant strains. This phenomenon has triggered an alarming public health concern due to the increase number of pathogenic Vibrio strains that are resistant to clinically used antibiotics and is found in the environment. Antibiotic resistance and the genes location in the strains can be detected through plasmid curing assay. The results derived from plasmid curing assay is fast, cost effective, sufficient in providing insights, and influence the antibiotic management policies in the aquaculture industry. This presentation aims in discussing and providing insights on various curing agents in Vibrio species. To our best of knowledge, this is a first review written discussing on plasmid curing in Vibrio species. PMID:26347714

  8. Evaluation of molecular methods to discriminate the closely related species Vibrio fluvialis and Vibrio furnissii.

    PubMed

    Schirmeister, Falko; Wieczorek, Angelina; Dieckmann, Ralf; Taureck, Karin; Strauch, Eckhard

    2014-10-01

    Vibrio furnissii and Vibrio fluvialis are two closely related species which are regarded as emerging human pathogens. Human infections have been mainly associated with consumption of seafood or drinking of contaminated water. V. furnissii strains can be distinguished from V. fluvialis by their ability to produce gas from fermentation of carbohydrates. In this study, we compare two phenotypic (biochemical testing and matrix-assisted laser desorption/ionisation time of flight mass spectrometry, MALDI-TOF MS) and three genotypic techniques (rpoB sequencing, conventional PCR and real-time PCR) for determination of the two species. The methods were evaluated on a collection of 42 V. furnissii and 32 V. fluvialis strains, which were isolated from marine environments and from animals intended for food production. Four of the applied methods allowed the unambiguous discrimination of the two species, while the biochemical testing was the least reliable technique, due to a high variation in the phenotype of gas production from carbohydrates. In view of the One Health concept reliable diagnostic techniques are a prerequisite for preventive public health measurements, as pathogens isolated from animals can cross species borders and methods for detection of sources, reservoirs and ways of transmission of pathogenic bacteria are indispensable for the prevention of infectious diseases in humans and animals. PMID:25242722

  9. 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 5C, 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

  10. Signature-tagged mutagenesis of Vibrio vulnificus

    PubMed Central

    YAMAMOTO, Mai; KASHIMOTO, Takashige; TONG, Ping; XIAO, Jianbo; SUGIYAMA, Michiko; INOUE, Miyuki; MATSUNAGA, Rie; HOSOHARA, Kohei; NAKATA, Kazue; YOKOTA, Kenji; OGUMA, Keiji; YAMAMOTO, Koichiro

    2015-01-01

    Vibrio vulnificus is the causative agent of primary septicemia, wound infection and gastroenteritis in immunocompromised people. In this study, signature-tagged mutagenesis (STM) was applied to identify the virulence genes of V. vulnificus. Using STM, 6,480 mutants in total were constructed and divided into 81 sets (INPUT pools); each mutant in a set was assigned a different tag. Each INPUT pool was intraperitoneally injected into iron-overloaded mice, and in vivo surviving mutants were collected from blood samples from the heart (OUTPUT pools). From the genomic DNA of mixed INPUT or OUTPUT pools, digoxigenin-labeled DNA probes against the tagged region were prepared and used for dot hybridization. Thirty tentatively attenuated mutants, which were hybridized clearly with INPUT probes but barely with OUTPUT probes, were negatively selected. Lethal doses of 11 of the 30 mutants were reduced to more than 1/100; of these, the lethal doses of 2 were reduced to as low as 1/100,000. Transposon-inserted genes in the 11 attenuated mutants were those for IMP dehydrogenase, UDP-N-acetylglucosamine-2-epimerase, aspartokinase, phosphoribosylformylglycinamidine cyclo-ligase, malate Na (+) symporter and hypothetical protein. When mice were immunized with an attenuated mutant strain into which IMP dehydrogenase had been inserted with a transposon, they were protected against V. vulnificus infection. In this study, we demonstrated that the STM method can be used to search for the virulence genes of V. vulnificus. PMID:25755021

  11. Signature-tagged mutagenesis of Vibrio vulnificus.

    PubMed

    Yamamoto, Mai; Kashimoto, Takashige; Tong, Ping; Xiao, Jianbo; Sugiyama, Michiko; Inoue, Miyuki; Matsunaga, Rie; Hosohara, Kohei; Nakata, Kazue; Yokota, Kenji; Oguma, Keiji; Yamamoto, Koichiro

    2015-07-01

    Vibrio vulnificus is the causative agent of primary septicemia, wound infection and gastroenteritis in immunocompromised people. In this study, signature-tagged mutagenesis (STM) was applied to identify the virulence genes of V. vulnificus. Using STM, 6,480 mutants in total were constructed and divided into 81 sets (INPUT pools); each mutant in a set was assigned a different tag. Each INPUT pool was intraperitoneally injected into iron-overloaded mice, and in vivo surviving mutants were collected from blood samples from the heart (OUTPUT pools). From the genomic DNA of mixed INPUT or OUTPUT pools, digoxigenin-labeled DNA probes against the tagged region were prepared and used for dot hybridization. Thirty tentatively attenuated mutants, which were hybridized clearly with INPUT probes but barely with OUTPUT probes, were negatively selected. Lethal doses of 11 of the 30 mutants were reduced to more than 1/100; of these, the lethal doses of 2 were reduced to as low as 1/100,000. Transposon-inserted genes in the 11 attenuated mutants were those for IMP dehydrogenase, UDP-N-acetylglucosamine-2-epimerase, aspartokinase, phosphoribosylformylglycinamidine cyclo-ligase, malate Na (+) symporter and hypothetical protein. When mice were immunized with an attenuated mutant strain into which IMP dehydrogenase had been inserted with a transposon, they were protected against V. vulnificus infection. In this study, we demonstrated that the STM method can be used to search for the virulence genes of V. vulnificus. PMID:25755021

  12. Relationship of aquatic environmental factors with the abundance of Vibrio cholerae, Vibrio parahaemolyticus, Vibrio mimicus and Vibrio vulnificus in the coastal area of Guaymas, Sonora, Mexico.

    PubMed

    Len Robles, A; Acedo Flix, E; Gomez-Gil, B; Quiones Ramrez, E I; Nevrez-Martnez, M; Noriega-Orozco, L

    2013-12-01

    Members of the genus Vibrio are common in aquatic environments. Among them are V. cholerae, V. vulnificus, V. parahaemolyticus and V. mimicus. Several studies have shown that environmental factors, such as temperature, salinity, and dissolved oxygen, are involved in their epidemiology. Therefore, the main objective of this study is to determine if there is a correlation between the presence/amount of V. cholerae, V, vulnificus, V. parahaemolyticus and V. mimicus and the environmental conditions of the seawater off the coast of Guaymas, Mxico. Quantification of all four pathogenic bacteria was performed using the most probable number method, and suspected colonies were identified by polymerase chain reaction (PCR). Correlations were found using principal component analysis. V. parahaemolyticus was the most abundant and widely distributed bacteria, followed by V. vulnificus, V. mimicus and V. cholerae. Positive correlations between V. parahaemolyticus, V. vulnificus and V. mimicus with temperature, salinity, electric conductivity, and total dissolved solids were found. The abundance of V. cholerae was mainly affected by the sampling site and not by physicochemical parameters. PMID:24334844

  13. Multiple enzymatic profiles of Vibrio parahaemolyticus strains isolated from oysters.

    PubMed

    Costa, Renata Albuquerque; Conde Amorim, Ludimila M M; Arajo, Rayza Lima; dos Fernandes Vieira, Regine H Silva

    2013-01-01

    The enzymatic characterization of vibrios has been used as a virulence indicator of sanitary interest. The objective of this study was to determine the enzymatic profile of Vibrio parahaemolyticus strains (n=70) isolated from Crassostrea rhizophorae oysters. The strains were examined for the presence of gelatinase (GEL), caseinase (CAS), elastase (ELAS), phospholipase (PHOS), lipase (LIP), amilase (AML) and DNase. All enzymes, except elastase, were detected in more than 60% of the strains. The most recurrent enzymatic profiles were AML + DNase + PHOS + GEL + LIP (n=16; 22.9%) and AML + CAS + DNase + PHOS + GEL + LIP (n=21; 30%). Considering the fact that exoenzyme production by vibrios is closely related to virulence, one must be aware of the bacteriological risk posed to human health by the consumption of raw or undercooked oysters. PMID:24401782

  14. Pneumonia caused by a previously undescribed bacterium.

    PubMed Central

    Hopfer, R L; Mills, K; Fainstein, V; Fischer, H E; Luna, M P

    1982-01-01

    A new and as yet unidentified bacterium was isolated from the lung tissue of a cancer patient with bilateral pneumonia. Clinically, the pneumonia was consistent with legionellosis; the organism cultured from the lung grew only on the charcoal-yeast extract agar routinely used for Legionella isolation. Subsequent testing, however, showed the organism to be quite distinct from the known Legionella species in its biochemical, antigenic, and growth characteristics. Images PMID:7130363

  15. 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

  16. 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.

  17. Diversity and Dynamics of a North Atlantic Coastal Vibrio Community

    PubMed Central

    Thompson, Janelle R.; Randa, Mark A.; Marcelino, Luisa A.; Tomita-Mitchell, Aoy; Lim, Eelin; Polz, Martin F.

    2004-01-01

    Vibrios are ubiquitous marine bacteria that have long served as models for heterotrophic processes and have received renewed attention because of the discovery of increasing numbers of facultatively pathogenic strains. Because the occurrence of specific vibrios has frequently been linked to the temperature, salinity, and nutrient status of water, we hypothesized that seasonal changes in coastal water bodies lead to distinct vibrio communities and sought to characterize their level of differentiation. A novel technique was used to quantify shifts in 16S rRNA gene abundance in samples from Barnegat Bay, N.J., collected over a 15-month period. Quantitative PCR (QPCR) with primers specific for the genus Vibrio was combined with separation and quantification of amplicons by constant denaturant capillary electrophoresis (CDCE). Vibrio populations identified by QPCR-CDCE varied between summer and winter samples, suggesting distinct warm-water and year-round populations. Identification of the CDCE populations by cloning and sequencing of 16S rRNA genes from two summer and two winter samples confirmed this distinction. It further showed that CDCE populations corresponded in most cases to ?98% rRNA similarity groups and suggested that the abundance of these follows temperature trends. Phylogenetic comparison yielded closely related cultured and often pathogenic representatives for most sequences, and the temperature ranges of these isolates confirmed the trends seen in the environmental samples. Overall, this suggests that temperature is a good predictor of the occurrence of closely related vibrios but that considerable microdiversity of unknown significance coexists within this trend. PMID:15240289

  18. 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

  19. Rapid identification of Vibrio cholerae by darkfield microscopy*

    PubMed Central

    Benenson, A. S.; Islam, M. R.; Greenough, W. B.

    1964-01-01

    This article describes a rapid, simple and reproducible method for detecting Vibrio cholerae in diarrhoeal patients. The method involves darkfield examination of a liquid stool specimen or a rectal swab immersed in broth and immobilization of V. cholerae by the addition of specific vibrio antisera. The authors state that in 80% of cases a definitive diagnosis is available within five minutes. There is no need for elaborate equipment or long training of technicians and the method is easily performed by one person in the field. PMID:14215188

  20. 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.

  1. Vibrio salilacus sp. nov., a new member of the Anguillarum clade with six alleles of the 16S rRNA gene from a saline lake.

    PubMed

    Zhong, Zhi-Ping; Liu, Ying; Liu, Hong-Can; Wang, Fang; Zhou, Yu-Guang; Liu, Zhi-Pei

    2015-08-01

    A Gram-stain-negative, catalase- and oxidase-positive, facultatively aerobic bacterium, strain DSG-S6T, was isolated from Dasugan Lake (salinity 3.1%, w/w), China. Its taxonomic position was determined by using a polyphasic approach. Cells of strain DSG-S6T were non-spore-forming, slightly bent rods, and motile by means of a single polar flagellum. Growth occurred in the presence of 0-7.0% (w/v) NaCl (optimum, 2.0%), at 4-35?C (optimum, 30?C) and at pH?6.0-10.5 (optimum, pH?8.0-8.5). C16?:?0, C18?:?1?7c and C16?:?1?7c and/or C16?:?1?6c were the major fatty acids. Six alleles of the 16S rRNA gene sharing 98.9-99.9??% similarity were detected in strain DSG-S6T, which showed highest 16S rRNA gene sequence similarity to Vibrio aestuarianus ATCC 35048T (97.7?%), then to Vibrio pacinii LMG 19999T (97.6%) and Vibrio metschnikovii CIP 69.14T (96.8%). Multilocus sequence analysis of four housekeeping genes and 16S rRNA genes clearly clustered it as a member of the Anguillarum clade. Mean DNA-DNA relatedness between strain DSG-S6T and V. aestuarianus NBRC 15629T, V. pacinii CGMCC 1.12557T and V. metschnikovii JCM 21189T was 20.6??2.3, 38.1??3.5 and 24.2??2.8%, respectively. The DNA G+C content was 46.8?mol% (Tm). Based on the data, it is concluded that strain DSG-S6T represents a novel species of the genus Vibrio, for which the name Vibrio salilacus sp. nov. is proposed. The type strain is DSG-S6T (?=?CGMCC 1.12427T?=?JCM 19265T). PMID:25964518

  2. Desulfovibrio alkalitolerans sp. nov., a novel alkalitolerant, sulphate-reducing bacterium isolated from district heating water.

    PubMed

    Abildgaard, Lone; Nielsen, Marie Bank; Kjeldsen, Kasper Urup; Ingvorsen, Kjeld

    2006-05-01

    A novel alkalitolerant, sulphate-reducing bacterium (strain RT2T) was isolated from alkaline district heating water. Strain RT2T was a motile vibrio (0.5-0.8 microm wide and 1.4-1.9 microm long) and grew at pH 6.9-9.9 (optimum at pH 9.0-9.4) and at 16-47 degrees C (optimum at 43 degrees C). The genomic DNA G+C content was 64.7 mol%. A limited number of compounds were used as electron donors with sulphate as electron acceptor, including lactate, pyruvate, formate and hydrogen/acetate. Sulphite and thiosulphate also served as electron acceptors. Based on physiological and genotypic properties, the isolate was considered to represent a novel species of the genus Desulfovibrio, for which the name Desulfovibrio alkalitolerans sp. nov. is proposed. The type strain is RT2T (=DSM 16529T=JCM 12612T). The strain is the first alkali-tolerant member of the genus Desulfovibrio to be described. PMID:16627648

  3. Pyrosequencing-Based Comparative Genome Analysis of Vibrio vulnificus Environmental Isolates

    PubMed Central

    Morrison, Shatavia S.; Williams, Tiffany; Cain, Aurora; Froelich, Brett; Taylor, Casey; Baker-Austin, Craig; Verner-Jeffreys, David; Hartnell, Rachel; Oliver, James D.; Gibas, Cynthia J.

    2012-01-01

    Between 1996 and 2006, the US Centers for Disease Control reported that the only category of food-borne infections increasing in frequency were those caused by members of the genus Vibrio. The Gram-negative bacterium Vibrio vulnificus is a ubiquitous inhabitant of estuarine waters, and is the number one cause of seafood-related deaths in the US. Many V. vulnificus isolates have been studied, and it has been shown that two genetically distinct subtypes, distinguished by 16S rDNA and other gene polymorphisms, are associated predominantly with either environmental or clinical isolation. While local genetic differences between the subtypes have been probed, only the genomes of clinical isolates have so far been completely sequenced. In order to better understand V. vulnificus as an agent of disease and to identify the molecular components of its virulence mechanisms, we have completed whole genome shotgun sequencing of three diverse environmental genotypes using a pyrosequencing approach. V. vulnificus strain JY1305 was sequenced to a depth of 33, and strains E64MW and JY1701 were sequenced to lesser depth, covering approximately 99.9% of each genome. We have performed a comparative analysis of these sequences against the previously published sequences of three V. vulnificus clinical isolates. We find that the genome of V. vulnificus is dynamic, with 1.27% of genes in the C-genotype genomes not found in the E- genotype genomes. We identified key genes that differentiate between the genomes of the clinical and environmental genotypes. 167 genes were found to be specifically associated with environmental genotypes and 278 genes with clinical genotypes. Genes specific to the clinical strains include components of sialic acid catabolism, mannitol fermentation, and a component of a Type IV secretory pathway VirB4, as well as several other genes with potential significance for human virulence. Genes specific to environmental strains included several that may have implications for the balance between self-preservation under stress and nutritional competence. PMID:22662170

  4. Use of mutant strain for evaluating processing strategies to inactivate Vibrio vulnificus in oysters.

    PubMed

    Dombroski, C S; Jaykus, L A; Green, D P; Farkas, B E

    1999-06-01

    Vibrio vulnificus is a ubiquitous marine bacterium frequently isolated from shellfish and associated with severe and often fatal disease in humans. Various control strategies to reduce the disease risk associated with V. vulnificus contamination in shellfish have been proposed. However, evaluating the efficacy of these control strategies is complicated because of the difficulty in distinguishing V. vulnificus from the high levels of background environmental Vibrio spp. The purpose of this research was to develop a model indicator V. vulnificus strain that could be readily differentiated from background microflora and used to facilitate the evaluation of processing efficacy. A spontaneous nalidixic acid-resistant strain of V. vulnificus (Vv-NA) was prepared from a wild-type parent (Vv-WT) using selective plating techniques. Vv-NA was very similar to Vv-WT with respect to biochemical characteristics, appearance on selective plating media, detection limits using most probable number and polymerase chain reaction, and growth rate. In comparative freeze inactivation studies on pure cultures, Vv-WT and Vv-NA had similar freeze inactivation profiles at -20 degrees C (conventional freezing), at -85 degrees C (cold blast freezing), and in liquid nitrogen (cryogenic freezing). In oyster homogenates artificially inoculated with Vv-NA, the organism was inactivated 95 to 99% after freezing, irrespective of freezing temperature. Thermal inactivation comparisons of pure cultures of Vv-WT and Vv-NA using the capillary tube method revealed statistically significant differences in D values at 47 degrees C (2.2 versus 3.0 min, respectively) and 50 degrees C (0.83 versus 0.56 min, respectively), but nearly identical values at 52 degrees C (0.21 versus 0.22 min, respectively). However, these D values were notably higher than those reported by other investigators and hence provided a conservative means by which to evaluate thermal inactivation. In oyster homogenates seeded with Vv-NA, D values of 1.3+/-0.09 min and 0.41+/-0.01 min were obtained at 46 degrees C and 48 degrees C, respectively. This study demonstrated that Vv-NA is readily enumerated and could be used as a surrogate for evaluating the degree of V. vulnificus inactivation provided by freezing and thermal treatments of oyster homogenates. PMID:10382646

  5. Reaction mechanism of chitobiose phosphorylase from Vibrio proteolyticus: identification of family 36 glycosyltransferase in Vibrio.

    PubMed Central

    Honda, Yuji; Kitaoka, Motomitsu; Hayashi, Kiyoshi

    2004-01-01

    A family 36 glycosyltransferase gene was cloned from Vibrio proteolyticus. The deduced amino acid sequence showed a high degree of identity with ChBP (chitobiose phosphorylase) from another species, Vibrio furnissii. The recombinant enzyme catalysed the reversible phosphorolysis of (GlcNAc)2 (chitobiose) to form 2-acetamide-2-deoxy-alpha-D-glucose 1-phosphate [GlcNAc-1-P] and GlcNAc, but showed no activity on cellobiose, indicating that the enzyme was ChBP, not cellobiose phosphorylase. In the synthetic reaction, the ChBP was active with alpha-D-glucose 1-phosphate as the donor substrate as well as GlcNAc-1-P to produce beta-D-glucosyl-(1-->4)-2-acetamide-2-deoxy-D-glucose with GlcNAc as the acceptor substrate. The enzyme allowed aryl-beta-glycosides of GlcNAc as the acceptor substrate with 10-20% activities of GlcNAc. Kinetic parameters of (GlcNAc)2 in the phosphorolysis and GlcNAc-1-P in the synthetic reaction were determined as follows: phosphorolysis, k(0)=5.5 s(-1), K(m)=2.0 mM; synthetic reaction, k(0)=10 s(-1), K(m)=14 mM, respectively. The mechanism of the phosphorolytic reaction followed a sequential Bi Bi mechanism, as frequently observed with cellobiose phosphorylases. Substrate inhibition by GlcNAc was observed in the synthetic reaction. The enzyme was considered a unique biocatalyst for glycosidation. PMID:13678418

  6. Characterization and distribution of Vibrio alginolyticus and Vibrio parahaemolyticus isolated in Indonesia.

    PubMed Central

    Molitoris, E; Joseph, S W; Krichevsky, M I; Sindhuhardja, W; Colwell, R R

    1985-01-01

    Previous studies have shown that Vibrio alginolyticus and Vibrio parahaemolyticus can be isolated from similar types of marine samples. In this report, the results of an examination of 567 V. alginolyticus and V. parahaemolyticus strains, isolated from seawater in Jakarta Bay and from more than 30 types of seafood from markets in Jakarta, Indonesia, are presented. Most isolates were from mackerel, shrimp, or squid. Numerical taxonomic analyses clustered 337 isolates and three V. alginolyticus reference strains at S greater than or equal to 80%. These strains produced acid from sucrose, but only approximately 80% produced acetoin or grew in the presence of 10% NaCl. The frequency of occurrence of V. alginolyticus in seawater samples ranged from 0% (in February and March 1972) to 100% (in September and December 1972) and was highest in seafood samples from August to December 1972. A second cluster of 230 isolates and seven V. parahaemolyticus reference strains was observed at S greater than or equal to 82%. These strains did not produce acetoin or acid from sucrose, and approximately 20% grew in the presence of 10% NaCl. V. parahaemolyticus was detected in seawater samples each month, with the highest frequency of occurrence (83.3%) in May 1972. Twenty-nine K antigen serotypes were demonstrated in V. parahaemolyticus isolates, and another 40% were untypable. The modal antibiotic resistance pattern for each species included five drugs. Only 12% of the V. parahaemolyticus strains were Kanagawa positive, and 10% elicited fluid accumulation in ligated rabbit ileal loops. All of the 7 V. alginolyticus strains and 94 (70%) of the V. parahaemolyticus strains tested killed mice when inoculated intraperitoneally.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:4091566

  7. Vibrio trends in the ecology of the Venice lagoon.

    PubMed

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

    2014-04-01

    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

  8. 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

  9. Chemiosmotic mechanism of antimicrobial activity of Ag(+) in Vibrio cholerae.

    PubMed

    Dibrov, Pavel; Dzioba, Judith; Gosink, Khoosheh K; Hse, Claudia C

    2002-08-01

    Although the antimicrobial effects of silver salts were noticed long ago, the molecular mechanism of the bactericidal action of Ag(+) in low concentrations has not been elucidated. Here, we show that low concentrations of Ag(+) induce a massive proton leakage through the Vibrio cholerae membrane, which results in complete deenergization and, with a high degree of probability, cell death. PMID:12121953

  10. Chemiosmotic Mechanism of Antimicrobial Activity of Ag+ in Vibrio cholerae

    PubMed Central

    Dibrov, Pavel; Dzioba, Judith; Gosink, Khoosheh K.; Hse, Claudia C.

    2002-01-01

    Although the antimicrobial effects of silver salts were noticed long ago, the molecular mechanism of the bactericidal action of Ag+ in low concentrations has not been elucidated. Here, we show that low concentrations of Ag+ induce a massive proton leakage through the Vibrio cholerae membrane, which results in complete deenergization and, with a high degree of probability, cell death. PMID:12121953

  11. Characterization of the melanogenic system in Vibrio cholerae, ATCC 14035.

    PubMed

    Ruzafa, C; Sanchez-Amat, A; Solano, F

    1995-06-01

    The nature of the pigment formed by Vibrio cholerae and the characterization of its biosynthetic pathway is shown. This microorganism is able to synthesize melanin-like pigment when cultured in the presence of L-tyrosine. Other phenolic chemicals related to L-tyrosine do not lead to pigment production. The microorganism has no tyrosine hydroxylase activity, and the levels of dopa oxidase activity are very low, making the existence of a tyrosinase very unlikely. However, Vibrio cholerae contained transaminases that transforms L-tyrosine into p-hydroxyphenylpyruvate. Moreover, Vibrio cholerae is able to go further in the catabolic pathway, releasing a great amount of homogentisic acid. This acid can spontaneously be oxidized to its p-quinone form, which subsequently polymerizes leading to pigment formation. It is concluded that the pigment formed by Vibrio cholerae is not synthesized by the Raper-Mason pathway, but by a L-tyrosine catabolism pathway leading to homogentisic acid. Some simple properties of that melanin are compared to model eu- and pheomelanin, but no clear distinction could be stated, indicating the similarity between all these pigments. PMID:7567791

  12. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vibrio cholerae serological reagents. 866.3930 Section 866.3930 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3930...

  13. Vibrio ostreicida sp. nov., a new pathogen of bivalve larvae.

    PubMed

    Prado, Susana; Dubert, Javier; Romalde, Jesús L; Toranzo, Alicia E; Barja, Juan L

    2014-05-01

    The taxonomic position of the bivalve pathogen PP-203T was studied together with those of two similar isolates (PP-200 and PP-204). The bacterial strains were isolated from samples of young oyster spat in a bivalve hatchery in Galicia (NW Spain), which was continually affected by outbreaks of disease and severe mortalities. On the basis of 16S rRNA gene sequencing, the three strains formed a cluster within the genus Vibrio and were most closely related to Vibrio pectenicida DSM 19585T (97.9% similarity). Additional multilocus sequence analysis, including sequences of the housekeeping genes rpoA, recA, pyrH, gyrB and ftsZ, and DNA-DNA hybridization experiments indicated that the strains were distinct from currently known species of the genus Vibrio and confirmed the clustering of the three isolates. Several phenotypic features, such as growth in TCBS medium and nitrate reduction, proved useful for distinguishing the proposed novel species from its closest relatives. The findings support the description of a novel species to include the three isolates, for which the name Vibrio ostreicida sp. nov. (type strain PP-203T=CECT 7398T=DSM 21433T) is proposed. PMID:24510976

  14. 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 ...

  15. 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...

  16. Molecular epidemiology of Vibrio cholerae in Hong Kong.

    PubMed Central

    Yam, W C; Lung, M L; Ng, K Y; Ng, M H

    1989-01-01

    We studied restriction fragment length polymorphism of the enterotoxin genes of isolates of Vibrio cholerae El Tor, indistinguishable by bacteriophage typing, which were collected in Hong Kong since 1978. Using this approach, we could distinguish indigenous and exogenous strains obtained from different sources and epidemiological settings. Images PMID:2570082

  17. The RNA Domain Vc1 Regulates Downstream Gene Expression in Response to Cyclic Diguanylate in Vibrio cholerae

    PubMed Central

    Kariisa, Ankunda T.; Weeks, Kevin; Tamayo, Rita

    2016-01-01

    In many bacterial species, including the aquatic bacterium and human pathogen Vibrio cholerae, the second messenger cyclic diguanylate (c-di-GMP) modulates processes such as biofilm formation, motility, and virulence factor production. By interacting with various effectors, c-di-GMP regulates gene expression or protein function. One type of c-di-GMP receptor is the class I riboswitch, representatives of which have been shown to bind c-di-GMP in vitro. Herein, we examined the in vitro and in vivo function of the putative class I riboswitch in Vibrio cholerae, Vc1, which lies upstream of the gene encoding GbpA, a colonization factor that contributes to attachment of V. cholerae to environmental and host surfaces containing N-acetylglucosamine moieties. We provide evidence that Vc1 RNA interacts directly with c-di-GMP in vitro, and that nucleotides conserved among this class of riboswitch are important for binding. Yet the mutation of these conserved residues individually in the V. cholerae chromosome inconsistently affects the expression of gbpA and production of the GbpA protein. By isolating the regulatory function of Vc1, we show that the Vc1 element positively regulates downstream gene expression in response to c-di-GMP. Together these data suggest that the Vc1 element responds to c-di-GMP in vivo. Positive regulation of gbpA expression by c-di-GMP via Vc1 may influence the ability of V. cholerae to associate with chitin in the aquatic environment and the host intestinal environment. PMID:26849223

  18. 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

  19. 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

  20. Vibrio vulnificus Phage PV94 Is Closely Related to Temperate Phages of V. cholerae and Other Vibrio Species

    PubMed Central

    Reetz, Jochen; Strauch, Eckhard; Hertwig, Stefan

    2014-01-01

    Background Vibrio vulnificus is an important pathogen which can cause serious infections in humans. Yet, there is limited knowledge on its virulence factors and the question whether temperate phages might be involved in pathogenicity, as is the case with V. cholerae. Thus far, only two phages (SSP002 and VvAW1) infecting V. vulnificus have been genetically characterized. These phages were isolated from the environment and are not related to Vibrio cholerae phages. The lack of information on temperate V. vulnificus phages prompted us to isolate those phages from lysogenic strains and to compare them with phages of other Vibrio species. Results In this study the temperate phage PV94 was isolated from a V. vulnificus biotype 1 strain by mitomycin C induction. PV94 is a myovirus whose genome is a linear double-stranded DNA of 33,828 bp with 5?-protruding ends. Sequence analysis of PV94 revealed a modular organization of the genome. The left half of the genome comprising the immunity region and genes for the integrase, terminase and replication proteins shows similarites to V. cholerae kappa phages whereas the right half containing genes for structural proteins is closely related to a prophage residing in V. furnissii NCTC 11218. Conclusion We present the first genomic sequence of a temperate phage isolated from a human V. vulnificus isolate. The sequence analysis of the PV94 genome demonstrates the wide distribution of closely related prophages in various Vibrio species. Moreover, the mosaicism of the PV94 genome indicates a high degree of horizontal genetic exchange within the genus Vibrio, by which V. vulnificus might acquire virulence-associated genes from other species. PMID:24732980

  1. [Establishment of loop-mediated isothermal amplification for detection of Vibrio alginolyticus].

    PubMed

    Ding, Wen Chao; Hu, Jian Rao; Shi, Yu Hong; Li, Ming Yun; Chen, Jiong

    2009-02-01

    Vibrio alginolyticus is the main Vibrio pathogen in aquaculture in the south of China. A one step loop-mediated isothermal amplification (LAMP) assay was developed for detection of Vibrio alginolyticus. A set of primers were designed from the OmpK sequence of Vibrio alginolyticus. The assay was optimised to amplify Vibrio alginolyticus DNA by incubation at 65 degrees C for only 1 h, and required only a simple water bath or heating block to provide a constant temperature of 65 degrees C. LAMP amplification products had a ladder-like appearance when electrophoresed on an agarose gel. The detection limit of the LAMP assay was n(cell) = 38/mL which was found to be higher than the commonly used PCR method. The assay was evaluated using clinical samples and the results indicated the suitability and simplicity of the test as a rapid, field diagnostic tool for Vibrio alginolyticus. PMID:19306691

  2. Culturable and VBNC Vibrio cholerae: interactions with chironomid egg masses and their bacterial population.

    PubMed

    Halpern, Malka; Landsberg, Ori; Raats, Dina; Rosenberg, Eugene

    2007-02-01

    Vibrio cholerae, the etiologic agent of cholera, is autochthonous to various aquatic environments. Recently, it was found that chironomid (nonbiting midges) egg masses serve as a reservoir for the cholera bacterium and that flying chironomid adults are possible windborne carriers of V. cholerae non-O1 non-O139. Chironomids are the most widely distributed insect in freshwater. Females deposit egg masses at the water's edge, and each egg mass contains eggs embedded in a gelatinous matrix. Hemagglutinin/protease, an extracellular enzyme of V. cholerae, was found to degrade chironomid egg masses and to prevent them from hatching. In a yearly survey, chironomid populations and the V. cholerae in their egg masses followed phenological succession and interaction of host-pathogen population dynamics. In this report, it is shown via FISH technique that most of the V. cholerae inhabiting the egg mass are in the viable but nonculturable (VBNC) state. The diversity of culturable bacteria from chironomid egg masses collected from two freshwater habitats was determined. In addition to V. cholerae, representatives of the following genera were isolated: Acinetobacter, Aeromonas, Klebsiella, Shewanella, Pseudomonas, Paracoccus, Exiguobacterium, and unidentified bacteria. Three important human pathogens, Aeromonas veronii, A. caviae, and A. hydrophila, were isolated from chironomid egg masses, indicating that chironomid egg masses may be a natural reservoir for pathogenic Aeromonas species in addition to V. cholerae. All isolates of V. cholerae were capable of degrading chironomid egg masses. This may help explain their host-pathogen relationship with chironomids. In contrast, almost none of the other bacteria that were isolated from the egg masses possessed this ability. Studying the interaction between chironomid egg masses, the bacteria inhabiting them, and V. cholerae could contribute to our understanding of the nature of the V. cholerae-egg mass interactions. PMID:17186156

  3. Biosynthesis of polyhydroxyalkanaotes by a novel facultatively anaerobic Vibrio sp. under marine conditions.

    PubMed

    Numata, Keiji; Doi, Yoshiharu

    2012-06-01

    Marine bacteria have recently attracted attention as potentially useful candidates for the production of practical materials from marine ecosystems, including the oceanic carbon dioxide cycle. The advantages of using marine bacteria for the biosynthesis of poly(hydroxyalkanoate) (PHA), one of the eco-friendly bioplastics, include avoiding contamination with bacteria that lack salt-water resistance, ability to use filtered seawater as a culture medium, and the potential for extracellular production of PHA, all of which would contribute to large-scale industrial production of PHA. A novel marine bacterium, Vibrio sp. strain KN01, was isolated and characterized in PHA productivity using various carbon sources under aerobic and aerobic-anaerobic marine conditions. The PHA contents of all the samples under the aerobic-anaerobic condition, especially when using soybean oil as the sole carbon source, were enhanced by limiting the amount of dissolved oxygen. The PHA accumulated using soybean oil as a sole carbon source under the aerobic-anaerobic condition contained 14% 3-hydroxypropionate (3HP) and 3% 5-hydroxyvalerate (5HV) units in addition to (R)-3-hydroxybutyrate (3HB) units and had a molecular weight of 42 × 10³ g/mol. The present result indicates that the activity of the beta-oxidation pathway under the aerobic-anaerobic condition is reduced due to a reduction in the amount of dissolved oxygen. These findings have potential for use in controlling the biosynthesis of long main-chain PHA by regulating the activity of the beta-oxidation pathway, which also could be regulated by varying the dissolved oxygen concentration. PMID:22068389

  4. Molecular and Genomic Characterization of Vibrio mimicus Isolated from a Frozen Shrimp Processing Facility in Mexico.

    PubMed

    Guardiola-Avila, Iliana; Acedo-Felix, Evelia; Sifuentes-Romero, Itzel; Yepiz-Plascencia, Gloria; Gomez-Gil, Bruno; Noriega-Orozco, Lorena

    2016-01-01

    Vibrio mimicus is a gram-negative bacterium responsible for diseases in humans. Three strains of V. mimicus identified as V. mimicus 87, V. mimicus 92 and V. mimicus 93 were isolated from a shrimp processing facility in Guaymas, Sonora, Mexico. The strains were analyzed using several molecular techniques and according to the cluster analysis they were different, their similarities ranged between 51.3% and 71.6%. ERIC-PCR and RAPD (vmh390R) were the most discriminatory molecular techniques for the differentiation of these strains. The complete genomes of two strains (V. mimicus 87, renamed as CAIM 1882, and V. mimicus 92, renamed as CAIM 1883) were sequenced. The sizes of the genomes were 3.9 Mb in both strains, with 2.8 Mb in ChI and 1.1 Mb in ChII. A 12.7% difference was found in the proteome content (BLAST matrix). Several virulence genes were detected (e.g. capsular polysaccharide, an accessory colonization factor and genes involved in quorum-sensing) which were classified in 16 categories. Variations in the gene content between these genomes were observed, mainly in proteins and virulence genes (e.g., hemagglutinin, mobile elements and membrane proteins). According to these results, both strains were different, even when they came from the same source, giving an insight of the diversity of V. mimicus. The identification of various virulence genes, including a not previously reported V. mimicus gene (acfD) in ChI in all sequenced strains, supports the pathogenic potential of this species. Further analysis will help to fully understand their potential virulence, environmental impact and evolution. PMID:26730584

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

    PubMed Central

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

    2015-01-01

    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

  6. AinS quorum sensing regulates the Vibrio fischeri acetate switch.

    PubMed

    Studer, Sarah V; Mandel, Mark J; Ruby, Edward G

    2008-09-01

    The marine bacterium Vibrio fischeri uses two acyl-homoserine lactone (acyl-HSL) quorum-sensing systems. The earlier signal, octanoyl-HSL, produced by AinS, is required for normal colonization of the squid Euprymna scolopes and, in culture, is necessary for a normal growth yield. In examining the latter requirement, we found that during growth in a glycerol/tryptone-based medium, wild-type V. fischeri cells initially excrete acetate but, in a metabolic shift termed the acetate switch, they subsequently utilize the acetate, removing it from the medium. In contrast, an ainS mutant strain grown in this medium does not remove the excreted acetate, which accumulates to lethal levels. The acetate switch is characterized by the induction of acs, the gene encoding acetyl coenzyme A (acetyl-CoA) synthetase, leading to uptake of the excreted acetate. Wild-type cells induce an acs transcriptional reporter 25-fold, coincident with the disappearance of the extracellular acetate; in contrast, the ainS mutant did not display significant induction of the acs reporter. Supplementation of the medium of an ainS mutant with octanoyl-HSL restored normal levels of acs induction and acetate uptake. Additional mutant analyses indicated that acs regulation was accomplished through the regulator LitR but was independent of the LuxIR quorum-signaling pathway. Importantly, the acs mutant of V. fischeri has a competitive defect when colonizing the squid, indicating the importance of proper control of acetate metabolism in the light of organ symbiosis. This is the first report of quorum-sensing control of the acetate switch, and it indicates a metabolic connection between acetate utilization and cell density. PMID:18487321

  7. Enumeration of viable non-culturable Vibrio cholerae using propidium monoazide combined with quantitative PCR.

    PubMed

    Wu, Bin; Liang, Weili; Kan, Biao

    2015-08-01

    The well-known human pathogenic bacterium, Vibrio cholerae, can enter a physiologically viable but non-culturable (VBNC) state under stress conditions. The differentiation of VBNC cells and nonviable cells is essential for both disease prevention and basic research. Among all the methods for detecting viability, propidium monoazide (PMA) combined with real-time PCR is popular because of its specificity, sensitivity, and speed. However, the effect of PMA treatment is not consistent and varies among different species and conditions. In this study, with an initial cell concentration of 110(8) CFU/ml, time and dose-effect relationships of different PMA treatments were evaluated via quantitative real-time PCR using live cell suspensions, dead cell suspensions and VBNC cell suspensions of V. cholerae O1 El Tor strain C6706. The results suggested that a PMA treatment of 20 ?M PMA for 20 min was optimal under our conditions. This treatment maximized the suppression of the PCR signal from membrane-compromised dead cells but had little effect on the signal from membrane-intact live cells. In addition to the characteristics of PMA treatment itself, the initial concentration of the targeted bacteria showed a significant negative influence on the stability of PMA-PCR assay in this study. We developed a strategy that mimicked a 110(8) CFU/ml cell concentration with dead bacteria of a different bacterial species, the DNA of which cannot be amplified using the real time PCR primers. With this strategy, our optimal approach successfully overcame the impact of low cell density and generated stable and reliable results for counting viable cells of V. cholerae in the VBNC state. PMID:26001818

  8. 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

    2015-03-01

    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

  9. Molecular and Genomic Characterization of Vibrio mimicus Isolated from a Frozen Shrimp Processing Facility in Mexico

    PubMed Central

    Guardiola-Avila, Iliana; Acedo-Felix, Evelia; Sifuentes-Romero, Itzel; Yepiz-Plascencia, Gloria; Gomez-Gil, Bruno; Noriega-Orozco, Lorena

    2016-01-01

    Vibrio mimicus is a gram-negative bacterium responsible for diseases in humans. Three strains of V. mimicus identified as V. mimicus 87, V. mimicus 92 and V. mimicus 93 were isolated from a shrimp processing facility in Guaymas, Sonora, Mexico. The strains were analyzed using several molecular techniques and according to the cluster analysis they were different, their similarities ranged between 51.3% and 71.6%. ERIC-PCR and RAPD (vmh390R) were the most discriminatory molecular techniques for the differentiation of these strains. The complete genomes of two strains (V. mimicus 87, renamed as CAIM 1882, and V. mimicus 92, renamed as CAIM 1883) were sequenced. The sizes of the genomes were 3.9 Mb in both strains, with 2.8 Mb in ChI and 1.1 Mb in ChII. A 12.7% difference was found in the proteome content (BLAST matrix). Several virulence genes were detected (e.g. capsular polysaccharide, an accessory colonization factor and genes involved in quorum-sensing) which were classified in 16 categories. Variations in the gene content between these genomes were observed, mainly in proteins and virulence genes (e.g., hemagglutinin, mobile elements and membrane proteins). According to these results, both strains were different, even when they came from the same source, giving an insight of the diversity of V. mimicus. The identification of various virulence genes, including a not previously reported V. mimicus gene (acfD) in ChI in all sequenced strains, supports the pathogenic potential of this species. Further analysis will help to fully understand their potential virulence, environmental impact and evolution. PMID:26730584

  10. Prevalence and Antimicrobial Resistance of Vibrio parahaemolyticus Isolated from Raw Shellfish in Poland.

    PubMed

    Lopatek, Magdalena; Wieczorek, Kinga; Osek, Jacek

    2015-05-01

    Vibrio parahaemolyticus is a marine bacterium recognized as an important cause of gastroenteritis in humans consuming contaminated shellfish. In recent years, increasing resistance to ampicillin and aminoglycosides has been observed among V. parahaemolyticus isolates. However, the first-line antimicrobials such as tetracyclines and fluoroquinolones remained highly effective against these bacteria. The aim of this study was to evaluate the occurrence of V. parahaemolyticus in live bivalve molluscs available on the Polish market and to determine the antimicrobial resistance of the recovered isolates. A total of 400 shellfish samples (mussels, oysters, clams, and scallops) from 2009 to 2012 were tested using the International Organization for Standardization standard 21872-1 method and PCR for the species-specific toxR gene. Antimicrobial susceptibility of the isolates was determined using a microbroth dilution method. V. parahaemolyticus was identified in 70 (17.5%) of the 400 samples, and the toxR gene was confirmed in 64 (91.4%) of these isolates. Most of the isolates were recovered from clams (31 isolates; 48.4% prevalence) followed by mussels (17 isolates; 26.6% prevalence). More V. parahaemolyticus-positive samples were found between May and September (22.7% prevalence) than between October and April (11.4% prevalence). Antibiotic profiling revealed that most isolates were resistant to ampicillin (56 isolates; 87.5%) and to streptomycin (45 isolates; 70.3%), but all of them were susceptible to tetracycline and chloramphenicol. Forty-one isolates (64.1%) were resistant to two or more antimicrobials; however, only one isolate (1.6%) was resistant to three antimicrobial classes. The antimicrobials used in treatment of human V. parahaemolyticus infection had high efficacy against the bacterial isolates tested. This study is the first concerning antibiotic resistance of V. parahaemolyticus isolates in Poland, and the results obtained indicate that these bacteria may pose a health risk to consumers. PMID:25951402

  11. Correlations between Clinical Features and Mortality in Patients with Vibrio vulnificus Infection

    PubMed Central

    Zhao, Hong; Xu, Lichen; Dong, Huihui; Hu, Jianhua; Gao, Hainv; Yang, Meifang; Zhang, Xuan; Chen, Xiaoming; Fan, Jun; Ma, Weihang

    2015-01-01

    Vibrio vulnificus is a common gram-negative bacterium, which might cause morbidity and mortality in patients following consumption of seafood or exposure to seawater in Southeast China. We retrospectively analyzed clinical data of patients with laboratory confirmed V. vulnificus infection. Twenty one patients were divided into a survival group and a non-surviving (or death) group according to their clinical outcome. Clinical data and measurements were statistically analyzed. Four patients (19.05%) died and five patients gave positive cultures from bile fluid, and 16 other patients gave positive culture from blood or blisters. Ten patients (47.62%) had an underlying liver disease and marine-related events were found in sixteen patients (76.2%). Patients with heavy drinking habits might be at increased mortality (p = 0.028). Clinical manifestations of cellulitis (47.6%), septic shock (42.9%) and multiple organ failure (28.6%) were statistically significant when comparing survivors and non-survivors (p = 0.035, p = 0.021 and p = 0.003, respectively). The laboratory results, including hemoglobin < 9.0 g/L (p = 0.012), platelets < 2.0109 /L, prothrombin time activity (PTA) <20%, decreased serum creatinine and increased urea nitrogen were statistically significant (p = 0.012, p = 0.003, p = 0.028 and p = 0.028, respectively). Patients may be at a higher risk of mortality under situations where they have a history of habitual heavy alcoholic drink consumption (p = 0.028, OR = 22.5, 95%CI 1.5335.3), accompanied with cellulitis, shock, multiple organ failure, and laboratory examinations that are complicated by decreased platelets, hemoglobin and significantly prolonged prothrombin time (PT). PMID:26274504

  12. 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

  13. Vibrio cholerae FabV defines a new class of enoyl-acyl carrier protein reductase.

    PubMed

    Massengo-Tiass, R Prisca; Cronan, John E

    2008-01-18

    Enoyl-acyl carrier protein (ACP) reductase catalyzes the last step of the fatty acid elongation cycle. The paradigm enoyl-ACP reductase is the FabI protein of Escherichia coli that is the target of the antibacterial compound, triclosan. However, some Gram-positive bacteria are naturally resistant to triclosan due to the presence of the triclosan-resistant enoyl-ACP reductase isoforms, FabK and FabL. The genome of the Gram-negative bacterium, Vibrio cholerae lacks a gene encoding a homologue of any of the three known enoyl-ACP reductase isozymes suggesting that this organism encodes a novel fourth enoyl-ACP reductase isoform. We report that this is the case. The gene encoding the new isoform, called FabV, was isolated by complementation of a conditionally lethal E. coli fabI mutant strain and was shown to restore fatty acid synthesis to the mutant strain both in vivo and in vitro. Like FabI and FabL, FabV is a member of the short chain dehydrogenase reductase superfamily, although it is considerably larger (402 residues) than either FabI (262 residues) or FabL (250 residues). The FabV, FabI and FabL sequences can be aligned, but only poorly. Alignment requires many gaps and yields only 15% identical residues. Thus, FabV defines a new class of enoyl-ACP reductase. The native FabV protein has been purified to homogeneity and is active with both crotonyl-ACP and the model substrate, crotonyl-CoA. In contrast to FabI and FabL, FabV shows a very strong preference for NADH over NADPH. Expression of FabV in E. coli results in markedly increased resistance to triclosan and the purified enzyme is much more resistant to triclosan than is E. coli FabI. PMID:18032386

  14. Recognition between symbiotic Vibrio fischeri and the hemocytes of Euprymna scolopes

    PubMed Central

    Nyholm, Spencer V.; Stewart, Jennifer J.; Ruby, Edward G.; McFall-Ngai, Margaret J.

    2008-01-01

    Summary The light-organ crypts of the squid Euprymna scolopes permit colonization exclusively by the luminous bacterium Vibrio fischeri. Because the crypt interior remains in contact with seawater, the squid must not only foster the specific symbiosis but also continue to exclude other bacteria. Investigation of the role of the innate immune system in these processes revealed that macrophage-like hemocytes isolated from E. scolopes recognized and phagocytosed V. fischeri less than other closely related bacterial species common to the host’s environment. Interestingly, phagocytes isolated from hosts that had been cured of their symbionts bound five-times more V. fischeri cells than those from uncured hosts. No such change in the ability to bind other species of bacteria was observed, suggesting that the host adapts specifically to V. fischeri. Deletion of the gene encoding OmpU, the major outer membrane protein of V. fischeri, increased binding by hemocytes from uncured animals to the level observed for hemocytes from cured animals. Co-incubation with wild-type V. fischeri reduced this binding, suggesting they produce a factor that complements the mutant’s defect. Analyses of the phagocytosis of bound cells by fluorescence-activated cell sorting (FACS) indicated that, once binding to hemocytes had occurred, V. fischeri cells are phagocytosed as effectively as other bacteria. Thus, discrimination by this component of the squid immune system occurs at the level of hemocyte binding, and this response: (i) is modified by previous exposure to the symbiont and, (ii) relies on outer membrane and/or secreted components of the symbionts. These data suggest that regulation of host hemocyte binding by the symbiont may be one of many factors that contribute to specificity in this association. PMID:19196278

  15. Vibrio cholerae Evades Neutrophil Extracellular Traps by the Activity of Two Extracellular Nucleases

    PubMed Central

    Seper, Andrea; Hosseinzadeh, Ava; Gorkiewicz, Gregor; Lichtenegger, Sabine; Roier, Sandro; Leitner, Deborah R.; Rhm, Marc; Grutsch, Andreas; Reidl, Joachim; Urban, Constantin F.; Schild, Stefan

    2013-01-01

    The Gram negative bacterium Vibrio cholerae is the causative agent of the secretory diarrheal disease cholera, which has traditionally been classified as a noninflammatory disease. However, several recent reports suggest that a V. cholerae infection induces an inflammatory response in the gastrointestinal tract indicated by recruitment of innate immune cells and increase of inflammatory cytokines. In this study, we describe a colonization defect of a double extracellular nuclease V. cholerae mutant in immunocompetent mice, which is not evident in neutropenic mice. Intrigued by this observation, we investigated the impact of neutrophils, as a central part of the innate immune system, on the pathogen V. cholerae in more detail. Our results demonstrate that V. cholerae induces formation of neutrophil extracellular traps (NETs) upon contact with neutrophils, while V. cholerae in return induces the two extracellular nucleases upon presence of NETs. We show that the V. cholerae wild type rapidly degrades the DNA component of the NETs by the combined activity of the two extracellular nucleases Dns and Xds. In contrast, NETs exhibit prolonged stability in presence of the double nuclease mutant. Finally, we demonstrate that Dns and Xds mediate evasion of V. cholerae from NETs and lower the susceptibility for extracellular killing in the presence of NETs. This report provides a first comprehensive characterization of the interplay between neutrophils and V. cholerae along with new evidence that the innate immune response impacts the colonization of V. cholerae in vivo. A limitation of this study is an inability for technical and physiological reasons to visualize intact NETs in the intestinal lumen of infected mice, but we can hypothesize that extracellular nuclease production by V. cholerae may enhance survival fitness of the pathogen through NET degradation. PMID:24039581

  16. Contribution of Six Flagellin Genes to the Flagellum Biogenesis of Vibrio vulnificus and In Vivo Invasion

    PubMed Central

    Kim, Soo Young; Thanh, Xuan Tran Thi; Jeong, Kwangjoon; Kim, Seong Bin; Pan, Sang O; Jung, Che Hun; Hong, Seol Hee

    2014-01-01

    Vibrio vulnificus is a halophilic pathogenic bacterium that is motile due to the presence of a single polar flagellum. V. vulnificus possesses a total of six flagellin genes organized into two loci (flaFBA and flaCDE). We proved that all six of the flagellin genes were transcribed, whereas only five (FlaA, -B, -C, -D, and -F) of the six flagellin proteins were detected. To understand roles of the six V. vulnificus flagellins in motility and virulence, mutants with single and multiple flagellin deletions were constructed. Mutations in flaB or flaC or the flaCDE locus resulted in a significant decrease in motility, adhesion, and cytotoxicity, whereas single mutations in the other flagellin genes or the flaFBA locus showed little or no effect. The motility was completely abolished only in the mutant lacking all six flagellin genes (flaFBA flaCDE). Surprisingly, a double mutation of flaB and flaD, a gene sharing 99% identity with the flaB at the amino acid level, resulted in the largest decrease in motility, adhesion, and cytotoxicity except for the mutant in which all six genes were deleted (the hexa mutant). Additionally, the 50% lethal doses (LD50s) of the flaB flaD and the flaFBA flaCDE mutants increased 23- and 91-fold in a mouse model, respectively, and the in vitro and in vivo invasiveness of the mutants was significantly decreased compared to that of the wild type. Taken together, the multiple flagellin subunits differentially contribute to the flagellum biogenesis and the pathogenesis of V. vulnificus, and among the six flagellin genes, flaB, flaD, and flaC were the most influential components. PMID:24101693

  17. Understanding the Role of Host Hemocytes in a Squid/Vibrio Symbiosis Using Transcriptomics and Proteomics

    PubMed Central

    Collins, Andrew J.; Schleicher, Tyler R.; Rader, Bethany A.; Nyholm, Spencer V.

    2012-01-01

    The symbiosis between the squid, Euprymna scolopes, and the bacterium, Vibrio fischeri, serves as a model for understanding interactions between beneficial bacteria and animal hosts. The establishment and maintenance of the association is highly specific and depends on the selection of V. fischeri and exclusion of non-symbiotic bacteria from the environment. Current evidence suggests that the hosts cellular innate immune system, in the form of macrophage-like hemocytes, helps to mediate host tolerance of V. fischeri. To begin to understand the role of hemocytes in this association, we analyzed these cells by high-throughput 454 transcriptomic and liquid chromatography/tandem mass spectrometry (LC-MS/MS) proteomic analyses. 454 high-throughput sequencing produced 650, 686 reads totaling 279.9?Mb while LC-MS/MS analyses of circulating hemocytes putatively identified 702 unique proteins. Several receptors involved with the recognition of microbial-associated molecular patterns were identified. Among these was a complete open reading frame to a putative peptidoglycan recognition protein (EsPGRP5) with conserved residues for amidase activity. Assembly of the hemocyte transcriptome showed EsPGRP5 had high coverage, suggesting it is among the 5% most abundant transcripts in circulating hemocytes. Other transcripts and proteins identified included members of the conserved NF-?B signaling pathway, putative members of the complement pathway, the carbohydrate binding protein galectin, and cephalotoxin. Quantitative Real-Time PCR of complement-like genes, cephalotoxin, EsPGRP5, and a nitric oxide synthase showed differential expression in circulating hemocytes from adult squid with colonized light organs compared to those isolated from hosts where the symbionts were removed. These data suggest that the presence of the symbiont influences gene expression of the cellular innate immune system of E. scolopes. PMID:22590467

  18. Prevalences of pathogenic and non-pathogenic Vibrio parahaemolyticus in mollusks from the Spanish Mediterranean Coast

    PubMed Central

    Lopez-Joven, Carmen; de Blas, Ignacio; Furones, M. Dolores; Roque, Ana

    2015-01-01

    Vibrio parahaemolyticus is a well-recognized pathogen of humans. To better understand the ecology of the human-pathogenic variants of this bacterium in the environment, a study on the prevalence in bivalves of pathogenic variants (tlh+ and tdh+ and/or trh+) versus a non-pathogenic one (only tlh+ as species marker for V. parahaemolyticus), was performed in two bays in Catalonia, Spain. Environmental factors that might affect dynamics of both variants of V. parahaemolyticus were taken into account. The results showed that the global prevalence of total V. parahaemolyticus found in both bays was 14.2% (207/1459). It was, however, significantly dependent on sampling point, campaign (year) and bivalve species. Pathogenic variants of V. parahaemolyticus (tdh+ and/or trh+) were detected in 3.8% of the samples (56/1459), meaning that the proportion of bivalves who contained tlh gene were contaminated by pathogenic V. parahaemolyticus strains is 27.1% (56/207). Moreover, the presence of pathogenic V. parahaemolyticus (trh+) was significantly correlated with water salinity, thus the probability of finding pathogenic V. parahaemolyticus decreased 1.45 times with every salinity unit (ppt) increased. Additionally, data showed that V. parahaemolyticus could establish close associations with Ruditapes spp. (P-value < 0.001), which could enhance the transmission of illness to human by pathogenic variants, when clams were eaten raw or slightly cooked. This study provides information on the abundance, ecology and characteristics of total and human-pathogenic V. parahaemolyticus variants associated with bivalves cultured in the Spanish Mediterranean Coast. PMID:26284033

  19. Prevalences of pathogenic and non-pathogenic Vibrio parahaemolyticus in mollusks from the Spanish Mediterranean Coast.

    PubMed

    Lopez-Joven, Carmen; de Blas, Ignacio; Furones, M Dolores; Roque, Ana

    2015-01-01

    Vibrio parahaemolyticus is a well-recognized pathogen of humans. To better understand the ecology of the human-pathogenic variants of this bacterium in the environment, a study on the prevalence in bivalves of pathogenic variants (tlh+ and tdh+ and/or trh+) versus a non-pathogenic one (only tlh+ as species marker for V. parahaemolyticus), was performed in two bays in Catalonia, Spain. Environmental factors that might affect dynamics of both variants of V. parahaemolyticus were taken into account. The results showed that the global prevalence of total V. parahaemolyticus found in both bays was 14.2% (207/1459). It was, however, significantly dependent on sampling point, campaign (year) and bivalve species. Pathogenic variants of V. parahaemolyticus (tdh+ and/or trh+) were detected in 3.8% of the samples (56/1459), meaning that the proportion of bivalves who contained tlh gene were contaminated by pathogenic V. parahaemolyticus strains is 27.1% (56/207). Moreover, the presence of pathogenic V. parahaemolyticus (trh+) was significantly correlated with water salinity, thus the probability of finding pathogenic V. parahaemolyticus decreased 1.45 times with every salinity unit (ppt) increased. Additionally, data showed that V. parahaemolyticus could establish close associations with Ruditapes spp. (P-value < 0.001), which could enhance the transmission of illness to human by pathogenic variants, when clams were eaten raw or slightly cooked. This study provides information on the abundance, ecology and characteristics of total and human-pathogenic V. parahaemolyticus variants associated with bivalves cultured in the Spanish Mediterranean Coast. PMID:26284033

  20. Seasonal dynamics and modeling of a Vibrio community in coastal waters of the North Sea.

    PubMed

    Oberbeckmann, Sonja; Fuchs, Bernhard M; Meiners, Mirja; Wichels, Antje; Wiltshire, Karen H; Gerdts, Gunnar

    2012-04-01

    Vibrio species are ubiquitously distributed in marine waters all over the world. High genome plasticity due to frequent mutation, recombination, and lateral gene transfer enables Vibrio to adapt rapidly to environmental changes. The genus Vibrio comprises several human pathogens, which commonly cause outbreaks of severe diarrhea in tropical regions. In recent years, pathogenic Vibrio emerged also in coastal European waters. Little is known about factors driving the proliferation of Vibrio spp. in temperate waters such as the North Sea. In this study a quantification of Vibrio in the North Sea and their response to biotic and abiotic parameters were assessed. Between January and December 2009, Vibrio at Helgoland Roads (North Sea, Germany) were quantified using fluorescence in situ hybridization. Vibrio numbers up to 3.4 10(4) cells mL(-1) (2.2% of total microbial counts) were determined in summer, but their abundance was significantly lower in winter (5 10(2) cells mL(-1)). Correlations between Vibrio and nutrients (SiO(2), PO(4) (3-), DIN), Secchi depth, temperature, salinity, and chlorophyll a were calculated using Spearman rank analysis. Multiple stepwise regression analysis was carried out to analyze the additive influence of multiple factors on Vibrio. Based on these calculations, we found that high water temperature and low salinity best explained the increase of Vibrio cell numbers. Other environmental parameters, especially nutrients and chlorophyll a, also had an influence. All variables were shown to be subject to the overall seasonal dynamics at Helgoland Roads. Multiple regression models could represent an efficient and reliable tool to predict Vibrio abundances in response to the climate change in European waters. PMID:22202887

  1. Selectivity and specificity of a chromogenic medium for detecting Vibrio parahaemolyticust.

    PubMed

    Su, Yi-Cheng; Duan, Jingyun; Wu, Wen-Hsin

    2005-07-01

    The thiosulfate-citrate-bile salts-sucrose agar (TCBS) used in the most-probable-number method for detecting Vibrio parahaemolyticus cannot differentiate growth of V. parahaemolyticus from Vibrio vulnificus or Vibrio mimicus. This study examined the selectivity and specificity of Bio-Chrome Vibrio medium (BCVM), a chromogenic medium that detects V. parahaemolyticus on the basis of the formation of distinct purple colonies on the medium. A panel consisting of 221 strains of bacteria, including 179 Vibrio spp. and 42 non-Vibrio spp., were examined for their ability to grow and produce colored colonies on BCVM. Growth of Salmonella, Shigella, Escherichia coli, Enterobacter cloacae, Yersinia enterocolitica, and Aeromonas was inhibited by both BCVM and TCBS. All 148 strains of V. parahaemolyticus grew on BCVM, and 145 of them produced purple colonies. The remaining 31 Vibrio spp., except one strain of Vibrio fluvialis, were either unable to grow or produced blue-green or white colonies on BCVM. Bio-Chrome Vibrio medium was capable of differentiating V. parahaemolyticus from other species, including V. vulnificus and V. mimicus. Further studies are needed to evaluate the sensitivity and specificity of BCVM for detecting V. parahaemolyticus in foods. PMID:16013386

  2. Crystallization and preliminary X-ray analysis of a class II release factor RF3 from a sulfate-reducing bacterium

    PubMed Central

    Kihira, Kiyohito; Numata, Shuko; Kitamura, Masaya; Kondo, Jun; Terawaki, Shinichi; Shomura, Yasuhito; Komori, Hirofumi; Shibata, Naoki; Higuchi, Yoshiki

    2008-01-01

    Class II release factor 3 (RF3) from the sulfate-reducing bacterium Desulfovibrio vulgaris Miyazaki F, which promotes rapid dissociation of a class I release factor, has been overexpressed, purified and crystallized in complex with GDP at 293?K using the sitting-drop vapour-diffusion method. A data set was collected to 1.8? resolution from a single crystal at 100?K using synchrotron radiation. The crystal belongs to space group P1, with unit-cell parameters a=47.39, b = 82.80, c = 148.29?, ? = 104.21, ? = 89.78, ? = 89.63. The asymmetric unit contains four molecules of the RF3GDP complex. The Matthews coefficient was calculated to be 2.3?3?Da?1 and the solvent content was estimated to be 46.6%. PMID:18607091

  3. Agrobacterium tumefaciens is a diazotrophic bacterium

    SciTech Connect

    Kanvinde, L.; Sastry, G.R.K. )

    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.

  4. Comparison of methods for the rapid recognition of cholera vibrios

    PubMed Central

    Finkelstein, Richard A.; Gomez, Cecilia Z.

    1963-01-01

    A comparison was made of three methods of bacteriological diagnosis during the outbreak of cholera due to Vibrio El Tor in the Republic of the Philippines in the last quarter of 1961. Although the disease was clinically indistinguishable from cholera caused by V. cholerae the etiological agent was a haemolytic, cholera-related vibrio which differed in some respects from what is classically regarded as V. cholerae. Of the three techniques evaluated, the selective-enrichment/fluorescent-antibody technique provided the most rapid and the greatest number of positive results in the 481 specimens examined in parallel. The oblique-light technique was second in sensitivity and rapidity, while the gelatin-agar method also had some advantages. Imagesp329-a PMID:20604143

  5. Vibrio bacteria in raw oysters: managing risks to human health.

    PubMed

    Froelich, Brett A; Noble, Rachel T

    2016-03-01

    The human-pathogenic marine bacteria Vibrio vulnificus and V. parahaemolyticus are strongly correlated with water temperature, with concentrations increasing as waters warm seasonally. Both of these bacteria can be concentrated in filter-feeding shellfish, especially oysters. Because oysters are often consumed raw, this exposes people to large doses of potentially harmful bacteria. Various models are used to predict the abundance of these bacteria in oysters, which guide shellfish harvest policy meant to reduce human health risk. Vibrio abundance and behaviour varies from site to site, suggesting that location-specific studies are needed to establish targeted risk reduction strategies. Moreover, virulence potential, rather than simple abundance, should be also be included in future modeling efforts. PMID:26880841

  6. Sources of Vibrio mimicus Contamination of Turtle Eggs

    PubMed Central

    Acua, Mara T.; Daz, Gerardo; Bolaos, Hilda; Barquero, Candy; Snchez, Olga; Snchez, Luz M.; Mora, Grettel; Chaves, Anny; Campos, Elena

    1999-01-01

    Vibrio mimicus contamination of sand increased significantly during the arrival of the olive ridley sea turtles (Lepidochelys olivacea) at Ostional anidation beach, Costa Rica. Statistical analysis supports that eggs are contaminated with V. mimicus by contact with the sand nest. V. mimicus was isolated from eggs of all nests tested, and ctxA+ strains were found in 31% of the nests, all of which were near the estuary. PMID:9872804

  7. Characterization of the Secretomes of Two Vibrios Pathogenic to Mollusks

    PubMed Central

    Madec, Stéphanie; Pichereau, Vianney; Jacq, Annick; Paillard, Mathieu; Boisset, Claire; Guérard, Fabienne

    2014-01-01

    Vibrio tapetis causes the brown ring disease in the Japanese clam Ruditapes philippinarum while Vibrio aestuarianus is associated with massive oyster mortalities. As extracellular proteins are often associated with the virulence of pathogenic bacteria, we undertook a proteomic approach to characterize the secretomes of both vibrios. The extracellular proteins (ECPs) of both species were fractionated by SEC-FPLC and in vitro assays were performed to measure the effects of each fraction on hemocyte cellular parameters (phagocytosis and adhesion). Fractions showing a significant effect were subjected to SDS-PAGE, and proteins were identified by nano LC-MS/MS. 45 proteins were identified for V. aestuarianus and 87 for V. tapetis. Most of them belonged to outer membrane or were periplasmic, including porins or adhesins that were already described as virulence factors in other bacterial species. Others were transporter components, flagella proteins, or proteins of unknown function (14 and 15 respectively). Interestingly, for V. aestuarianus, we noted the secretion of 3 extracellular enzymes including the Vam metalloprotease and two other enzymes (one putative lipase and one protease). For V. tapetis, we identified five extracellular enymes, i.e. two different endochitinases, one protease, one lipase and an adhesin. A comparison of both secretomes also showed that only the putative extracellular lipase was common to both secretomes, underscoring the difference in pathogenicity mechanisms between these two species. Overall, these results characterize for the first time the secretomes of these two marine pathogenic vibrios and constitute a useful working basis to further analyze the contribution of specific proteins in the virulence mechanisms of these species. PMID:25401495

  8. Characterization of the secretomes of two vibrios pathogenic to mollusks.

    PubMed

    Madec, Stphanie; Pichereau, Vianney; Jacq, Annick; Paillard, Mathieu; Boisset, Claire; Gurard, Fabienne; Paillard, Christine; Nicolas, Jean-Louis

    2014-01-01

    Vibrio tapetis causes the brown ring disease in the Japanese clam Ruditapes philippinarum while Vibrio aestuarianus is associated with massive oyster mortalities. As extracellular proteins are often associated with the virulence of pathogenic bacteria, we undertook a proteomic approach to characterize the secretomes of both vibrios. The extracellular proteins (ECPs) of both species were fractionated by SEC-FPLC and in vitro assays were performed to measure the effects of each fraction on hemocyte cellular parameters (phagocytosis and adhesion). Fractions showing a significant effect were subjected to SDS-PAGE, and proteins were identified by nano LC-MS/MS. 45 proteins were identified for V. aestuarianus and 87 for V. tapetis. Most of them belonged to outer membrane or were periplasmic, including porins or adhesins that were already described as virulence factors in other bacterial species. Others were transporter components, flagella proteins, or proteins of unknown function (14 and 15 respectively). Interestingly, for V. aestuarianus, we noted the secretion of 3 extracellular enzymes including the Vam metalloprotease and two other enzymes (one putative lipase and one protease). For V. tapetis, we identified five extracellular enymes, i.e. two different endochitinases, one protease, one lipase and an adhesin. A comparison of both secretomes also showed that only the putative extracellular lipase was common to both secretomes, underscoring the difference in pathogenicity mechanisms between these two species. Overall, these results characterize for the first time the secretomes of these two marine pathogenic vibrios and constitute a useful working basis to further analyze the contribution of specific proteins in the virulence mechanisms of these species. PMID:25401495

  9. Stimulation of macrophages by lipopolysaccharide of Vibrio parahaemolyticus.

    PubMed

    Bandekar, J R; Nerkar, D P

    1987-01-01

    The effect of lipopolysaccharide (LPS) from Vibrio parahaemolyticus on the biochemical and phagocytic activities of murine peritoneal macrophages was determined. Intraperitoneal treatment with different doses (0.5-25 micrograms) of V. parahaemolyticus LPS markedly increased the cellular RNA content as well as lysosomal enzyme activities of peritoneal macrophages. The treatment also stimulated the phagocytic activities of macrophages. These observations suggest that V. parahaemolyticus LPS causes stimulation of murine peritoneal macrophages. PMID:2449599

  10. Dynamics of Snake-like Swarming Behavior of Vibrio alginolyticus.

    PubMed

    Böttcher, Thomas; Elliott, Hunter L; Clardy, Jon

    2016-02-23

    Swarming represents a special case of bacterial behavior where motile bacteria migrate rapidly and collectively on surfaces. Swarming and swimming motility of bacteria has been studied well for rigid, self-propelled rods. In this study we report a strain of Vibrio alginolyticus, a species that exhibits similar collective motility but a fundamentally different cell morphology with highly flexible snake-like swarming cells. Investigating swarming dynamics requires high-resolution imaging of single cells with coverage over a large area: thousands of square microns. Researchers previously have employed various methods of motion analysis but largely for rod-like bacteria. We employ temporal variance analysis of a short time-lapse microscopic image series to capture the motion dynamics of swarming Vibrio alginolyticus at cellular resolution over hundreds of microns. Temporal variance is a simple and broadly applicable method for analyzing bacterial swarming behavior in two and three dimensions with both high-resolution and wide-spatial coverage. This study provides detailed insights into the swarming architecture and dynamics of Vibrio alginolyticus isolate B522 on carrageenan agar that may lay the foundation for swarming studies of snake-like, nonrod-shaped motile cell types. PMID:26910435

  11. Biocompatible capped iron oxide nanoparticles for Vibrio cholerae detection

    NASA Astrophysics Data System (ADS)

    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.

  12. Distribution ofVibrio cholerae in two Florida estuaries.

    PubMed

    Hood, M A; Ness, G E; Rodrick, G E; Blake, N J

    1983-04-01

    The distribution ofVibrio cholerae was examined in 2 Florida estuaries, Apalachicola and Tampa Bay.Vibrio cholerae serotype non-01 was the most abundant serotype, being isolated from 45% of the oyster samples, 30% of the sediments, 50% of the waters, and 75% of the blue crabs.Vibrio cholerae serotype 01 was isolated from only one oyster sample. Strong linear correlations betweenV. cholerae and temperature, salinity, or the other physical/chemical parameters measured,Escherichia coli, or fecal coliforms were not observed, but a range of temperatures and salinities appeared relevant to the distribution of the organism. The organism was present in the highest concentrations when salinities were 10-25 and temperatures were 20C-35C.In vitro growth curves of 95V. cholerae environmental isolates further supported that 10-25 was an ideal salinity range for the organisms. The results suggest thatV. cholerae is a widely distributed organism in the nutrient-rich warm waters of the Gulf Coast estuaries. PMID:24221617

  13. Genotype to phenotype: identification of diagnostic vibrio phenotypes using whole genome sequences.

    PubMed

    Amaral, Gilda Rose S; Dias, Graciela M; Wellington-Oguri, Michiyo; Chimetto, Luciane; Campeo, Mariana E; Thompson, Fabiano L; Thompson, Cristiane C

    2014-02-01

    Vibrios are ubiquitous in the aquatic environment and can be found in association with animal or plant hosts. The range of ecological relationships includes pathogenic and mutualistic associations. To gain a better understanding of the ecology of these microbes, it is important to determine their phenotypic features. However, the traditional phenotypic characterization of vibrios has been expensive, time-consuming and restricted in scope to a limited number of features. In addition, most of the commercial systems applied for phenotypic characterization cannot characterize the broad spectrum of environmental strains. A reliable and possible alternative is to obtain phenotypic information directly from whole genome sequences. The aim of the present study was to evaluate the usefulness of whole genome sequences as a source of phenotypic information. We performed a comparison of the vibrio phenotypes obtained from the literature with the phenotypes obtained from whole genome sequences. We observed a significant correlation between the previously published phenotypic data and the phenotypic data retrieved from whole genome sequences of vibrios. Analysis of 26 vibrio genomes revealed that all genes coding for the specific proteins involved in the metabolic pathways responsible for positive phenotypes of the 14 diagnostic features (Voges-Proskauer reaction, indole production, arginine dihydrolase, ornithine decarboxylase, utilization of myo-inositol, sucrose and L-leucine, and fermentation of D-mannitol, D-sorbitol, L-arabinose, trehalose, cellobiose, D-mannose and D-galactose) were found in the majority of the vibrios genomes. Vibrio species that were negative for a given phenotype revealed the absence of all or several genes involved in the respective biochemical pathways, indicating the utility of this approach to characterize the phenotypes of vibrios. The absence of the global regulation and regulatory proteins in the Vibrio parahaemolyticus genome indicated a non-vibrio phenotype. Whole genome sequences represent an important source for the phenotypic identification of vibrios. PMID:24505074

  14. 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

  15. Development of a Taqman real-time PCR assay for rapid detection and quantification of Vibrio tapetis in extrapallial fluids of clams

    PubMed Central

    Richard, Gaëlle G.; Le Bris, Cédric; Paillard, Christine

    2015-01-01

    The Gram-negative bacterium Vibrio tapetis is known as the causative agent of Brown Ring Disease (BRD) in the Manila clam Venerupis (=Ruditapes) philippinarum. This bivalve is the second most important species produced in aquaculture and has a high commercial value. In spite of the development of several molecular methods, no survey has been yet achieved to rapidly quantify the bacterium in the clam. In this study, we developed a Taqman real-time PCR assay targeting virB4 gene for accurate and quantitative identification of V. tapetis strains pathogenic to clams. Sensitivity and reproducibility of the method were assessed using either filtered sea water or extrapallial fluids of clam injected with the CECT4600T V. tapetis strain. Quantification curves of V. tapetis strain seeded in filtered seawater (FSW) or extrapallial fluids (EF) samples were equivalent showing reliable qPCR efficacies. With this protocol, we were able to specifically detect V. tapetis strains down to 1.125 101 bacteria per mL of EF or FSW, taking into account the dilution factor used for appropriate template DNA preparation. This qPCR assay allowed us to monitor V. tapetis load both experimentally or naturally infected Manila clams. This technique will be particularly useful for monitoring the kinetics of massive infections by V. tapetis and for designing appropriate control measures for aquaculture purposes. PMID:26713238

  16. Lack of Outer Membrane Protein A Enhances the Release of Outer Membrane Vesicles and Survival of Vibrio cholerae and Suppresses Viability of Acanthamoeba castellanii

    PubMed Central

    Valeru, Soni Priya; Shanan, Salah; Alossimi, Haifa; Sandstrm, Gunnar

    2014-01-01

    Vibrio cholerae, the causative agent of the diarrhoeal disease cholera, survives in aquatic environments. The bacterium has developed a survival strategy to grow and survive inside Acanthamoeba castellanii. It has been shown that V. cholerae expresses outer membrane proteins as virulence factors playing a role in the adherence to interacted host cells. This study examined the role of outer membrane protein A (OmpA) and outer membrane vesicles (OMVs) in survival of V. cholerae alone and during its interaction with A. castellanii. The results showed that an OmpA mutant of V. cholerae survived longer than wild-type V. cholerae when cultivated alone. Cocultivation with A. castellanii enhanced the survival of both bacterial strains and OmpA protein exhibited no effect on attachment, engulfment, and survival inside the amoebae. However, cocultivation of the OmpA mutant of V. cholerae decreased the viability of A. castellanii and this bacterial strain released more OMVs than wild-type V. cholerae. Surprisingly, treatment of amoeba cells with OMVs isolated from the OmpA mutant significantly decreased viable counts of the amoeba cells. In conclusion, the results might highlight a regulating rule for OmpA in survival of V. cholerae and OMVs as a potent virulence factor for this bacterium towards eukaryotes in the environment. PMID:24799908

  17. 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

  18. 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

  19. Crystallization and preliminary X-ray study of Vibrio cholerae uridine phosphorylase in complex with 6-methyluracil

    PubMed Central

    Prokofev, Igor I.; Lashkov, Alexander A.; Gabdulkhakov, Azat G.; Dontsova, Mariya V.; Seregina, Tatyana A.; Mironov, Alexander S.; Betzel, Christian; Mikhailov, Albert M.

    2014-01-01

    Uridine phosphorylase catalyzes the phosphorolysis of ribonucleosides, with the nitrogenous base and ribose 1-phosphate as products. Additionally, it catalyzes the reverse reaction of the synthesis of ribonucleosides from ribose 1-phosphate and a nitrogenous base. However, the enzyme does not catalyze the synthesis of nucleosides when the substrate is a nitrogenous base substituted at the 6-position, such as 6-methyluracil (6-MU). In order to explain this fact, it is essential to investigate the three-dimensional structure of the complex of 6-MU with uridine phosphorylase. 6-MU is a pharmaceutical agent that improves tissue nutrition and enhances cell regeneration by normalization of nucleotide exchange in humans. 6-MU is used for the treatment of diseases of the gastrointestinal tract, including infectious diseases. Here, procedures to obtain the uridine phosphorylase from the pathogenic bacterium Vibrio cholerae (VchUPh), purification of this enzyme, crystallization of the complex of VchUPh with 6-MU, and X-ray data collection and preliminary X-ray analysis of the VchUPh6-MU complex at atomic resolution are reported. PMID:24419619

  20. Virulence Profiles of Vibrio vulnificus in German Coastal Waters, a Comparison of North Sea and Baltic Sea Isolates

    PubMed Central

    Bier, Nadja; Jäckel, Claudia; Dieckmann, Ralf; Brennholt, Nicole; Böer, Simone I.; Strauch, Eckhard

    2015-01-01

    Vibrio vulnificus is a halophilic bacterium of coastal environments known for sporadically causing severe foodborne or wound infections. Global warming is expected to lead to a rising occurrence of V. vulnificus and an increasing incidence of human infections in Northern Europe. So far, infections in Germany were exclusively documented for the Baltic Sea coast, while no cases from the North Sea region have been reported. Regional variations in the prevalence of infections may be influenced by differences in the pathogenicity of V. vulnificus populations in both areas. This study aimed to compare the distribution of virulence-associated traits and genotypes among 101 V. vulnificus isolates from the Baltic Sea and North Sea in order to assess their pathogenicity potential. Furthermore, genetic relationships were examined by multilocus sequence typing (MLST). A high diversity of MLST sequences (74 sequence types) and differences regarding the presence of six potential pathogenicity markers were observed in the V. vulnificus populations of both areas. Strains with genotypes and markers associated with pathogenicity are not restricted to a particular geographic region. This indicates that lack of reported cases in the North Sea region is not caused by the absence of potentially pathogenic strains. PMID:26694432

  1. Response of Penaeus indicus females at two different stages of ovarian development to a lethal infection with Vibrio penaeicida.

    PubMed

    Avarre, J-C; Saulnier, D; Labreuche, Y; Ansquer, D; Tietz, A; Lubzens, Esther

    2003-01-01

    An association between vitellogenesis and the immune system was suggested in crustaceans from studies on plasma lipoproteins. The present research studies the effect of an experimentally induced bacterial infection on vitellogenesis in females of the shrimp Penaeus indicus, as a model for penaeid species. Pre-vitellogenic and vitellogenic P. indicus females were experimentally infected with an extremely pathogenic bacterium, Vibrio penaeicida. The peak in mortality occurred earlier in pre-vitellogenic animals than in vitellogenic ones, although the final mortality level ( approximately 64-74%) 52h post-infection was nearly the same for the two groups. Twenty hours after infection, the total number of haemocytes was significantly reduced in vitellogenic females while there was no change in the pre-vitellogenic group. Protein synthesis in ovaries was not significantly affected by infection, at the two stages of ovarian development. No differences were found in mRNA levels of shrimp ovarian peritrophin protein (SOP), but preliminary results showed that mRNA expression of vitellin (VT) was reduced in a heavily infected vitellogenic female. The total amount of lipids in the haemolymph of vitellogenic females was almost twice higher than that of pre-vitellogenic ones. However, there was no change in the total content of lipids, lipid classes and fatty acid distribution in haemolymph or hepatopancreas following infection. Although vitellogenic and pre-vitellogenic females probably respond differently to a lethal bacterial infection, physiological differences may be concealed by the rapid onset of mortality. PMID:12581716

  2. VasH is a transcriptional regulator of the type VI secretion system functional in endemic and pandemic Vibrio cholerae.

    PubMed

    Kitaoka, Maya; Miyata, Sarah T; Brooks, Teresa M; Unterweger, Daniel; Pukatzki, Stefan

    2011-12-01

    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

  3. In situ strain-level detection and identification of Vibrio parahaemolyticus using surface-enhanced Raman spectroscopy.

    PubMed

    Xu, Jiajie; Turner, Jeffrey W; Idso, Matthew; Biryukov, Stanley V; Rognstad, Laurel; Gong, Heng; Trainer, Vera L; Wells, Mark L; Strom, Mark S; Yu, Qiuming

    2013-03-01

    The outer membrane of a bacterium is composed of chemical and biological components that carry specific molecular information related to strains, growth stages, expressions to stimulation, and maybe even geographic differences. In this work, we demonstrate that the biochemical information embedded in the outer membrane can be used for rapid detection and identification of pathogenic bacteria using surface-enhanced Raman spectroscopy (SERS). We used seven different strains of the marine pathogen Vibrio parahaemolyticus as a model system. The strains represent four genetically distinct clades isolated from clinical and environmental sources in Washington, U.S.A. The unique quasi-3D (Q3D) plasmonic nanostructure arrays, optimized using finite-difference time-domain (FDTD) calculations, were used as SERS-active substrates for sensitive and reproducible detection of these bacteria. SERS barcodes were generated on the basis of SERS spectra and were used to successfully detect individual strains in both blind samples and mixtures. The sensing and detection methods developed in this work could have broad applications in the areas of environmental monitoring, biomedical diagnostics, and homeland security. PMID:23356387

  4. Effect of site-directed mutagenesis at the GGEEF domain of the biofilm forming GGEEF protein from Vibrio cholerae.

    PubMed

    Chouhan, Om Prakash; Bandekar, Divya; Hazra, Mousumi; Baghudana, Ashish; Hazra, Saugata; Biswas, Sumit

    2016-12-01

    Vibrio cholerae, the cause of seven noted pandemics, leads a dual lifecycle-one in the human host in its virulent form, and the other as a sessile, non-virulent bacterium in aquatic bodies in surface biofilms. Surface biofilms have been attributed to be associated with a ubiquitous protein domain present in all branches of bacteria, known as the GGD(/E)EF domain. While the diguanlyate cyclase activities of these proteins are universally established, the role of these proteins as diguanlyate-specific phosphodiesterases in conjunction with a EAL domain has also been reported. The VC0395_0300 protein from V. cholerae which shows biofilm forming abilities also acts as a phosphodiesterase. Interestingly, this GGD(/E)EF protein contains a EAL site in the reverse orientation. We attempted to mutate the GGEEF signature along the sequence by site-directed mutagenesis. The resultant mutants (Sebox5-7) did not show much difference in phosphodiesterase activity in comparison with the wild type protein (Sebox3), indicating the independence of the phosphodiesterase activity of the protein from the GGD(/E)EF domain. However, the ability of the mutants to form surface biofilm was significantly lesser in the case of mutations in the three central positions of the signature domain. PMID:26728467

  5. Virulence Profiles of Vibrio vulnificus in German Coastal Waters, a Comparison of North Sea and Baltic Sea Isolates.

    PubMed

    Bier, Nadja; Jckel, Claudia; Dieckmann, Ralf; Brennholt, Nicole; Ber, Simone I; Strauch, Eckhard

    2015-01-01

    Vibrio vulnificus is a halophilic bacterium of coastal environments known for sporadically causing severe foodborne or wound infections. Global warming is expected to lead to a rising occurrence of V. vulnificus and an increasing incidence of human infections in Northern Europe. So far, infections in Germany were exclusively documented for the Baltic Sea coast, while no cases from the North Sea region have been reported. Regional variations in the prevalence of infections may be influenced by differences in the pathogenicity of V. vulnificus populations in both areas. This study aimed to compare the distribution of virulence-associated traits and genotypes among 101 V. vulnificus isolates from the Baltic Sea and North Sea in order to assess their pathogenicity potential. Furthermore, genetic relationships were examined by multilocus sequence typing (MLST). A high diversity of MLST sequences (74 sequence types) and differences regarding the presence of six potential pathogenicity markers were observed in the V. vulnificus populations of both areas. Strains with genotypes and markers associated with pathogenicity are not restricted to a particular geographic region. This indicates that lack of reported cases in the North Sea region is not caused by the absence of potentially pathogenic strains. PMID:26694432

  6. 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

  7. Development of a polymerase chain reaction (PCR) test for the detection of virulent forms of Vibrio parahaemolyticus.

    PubMed

    Kadhim, H M; Miah, A; Munn, C B; Gilpin, M L

    2012-04-01

    Vibrio parahaemolyticus is a marine bacterium and some strains cause gastroenteritis in humans. Clinical isolates are thought to possess virulence factors that are absent from the majority of environmental isolates. Use of randomly amplified polymorphic DNA (RAPD)-PCR produced a unique 600bp amplicon (band Y) in the majority of clinical isolates and rarely in environmental isolates tested. The DNA from band Y was cloned and sequenced and found to code for an outer membrane protein (OMP). Two polymerase chain reaction (PCR) primers were designed to specifically amplify a 200bp unique sequence from presumptive virulent strains (PCR-OMP). The virulence of 23 clinical and 32 environmental isolates was assessed in cytotoxicity tests by treatment of Caco-2 cells with extracellular products (ECPs). All but two of the clinical isolates (91%) were positive for the 200bp PCR-OMP and their ECPs produced a significantly higher (p?

  8. Development of a real-time resistance measurement for Vibrio parahaemolyticus detection by the lecithin-dependent hemolysin gene.

    PubMed

    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 Mg(2+)), 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 (Mg(2+)) 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

  9. 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.

  10. Sediment and Vegetation as Reservoirs of Vibrio vulnificus in the Tampa Bay Estuary and Gulf of Mexico

    PubMed Central

    Chase, Eva; Young, Suzanne

    2015-01-01

    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

  11. Inactivation of a novel response regulator is necessary for biofilm formation and host colonization by Vibrio fischeri.

    PubMed

    Morris, Andrew R; Darnell, Cynthia L; Visick, Karen L

    2011-10-01

    The marine bacterium Vibrio fischeri uses a biofilm to promote colonization of its eukaryotic host Euprymna scolopes. This biofilm depends on the symbiosis polysaccharide (syp) locus, which is transcriptionally regulated by the RscS-SypG two-component regulatory system. An additional response regulator (RR), SypE, exerts both positive and negative control over biofilm formation. SypE is a novel RR protein, with its three putative domains arranged in a unique configuration: a central phosphorylation receiver (REC) domain flanked by two effector domains with putative enzymatic activities (serine kinase and serine phosphatase). To determine how SypE regulates biofilm formation and host colonization, we generated a library of SypE domain mutants. Our results indicate that the N-terminus inhibits biofilm formation, while the C-terminus plays a positive role. The phosphorylation state of SypE appears to regulate these opposing activities, as disruption of the putative site of phosphorylation results in a protein that constitutively inhibits biofilm formation. Furthermore, SypE restricts host colonization: (i) sypE mutants with constitutive inhibitory activity fail to efficiently initiate host colonization and (ii) loss of sypE partially alleviates the colonization defect of an rscS mutant. We conclude that SypE must be inactivated to promote symbiotic colonization by V. fischeri. PMID:21854462

  12. 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 <15C. 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 33.4C, 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

  13. 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

  14. 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.

  15. Molecular characterization and expression analysis of interferon-gamma in the large yellow croaker Larimichthys crocea.

    PubMed

    Chen, Ruan-Ni; Su, Yong-Quan; Wang, Jun; Liu, Min; Qiao, Ying; Mao, Yong; Ke, Qiao-Zhen; Han, Kun-Huang; Zheng, Wei-Qiang; Zhang, Jian-She; Wu, Chang-Wen

    2015-10-01

    The large yellow croaker Larimichthys crocea is an important mariculture fish species in China, and the bacterium Vibrio harveyi (V. harveyi) and the ciliate protozoan Cryptocaryon irritans (C. irritans) are the two major pathogens in its aquaculture sector. Interferon-gamma (IFN-γ) plays important roles in regulating both innate and cell mediated immune responses as an inflammatory cytokine. In this study, we obtained the nucleotide sequence of IFN-γ from the large yellow croaker (LcIFN-γ). The phylogenetic relationship tree of 18 available IFN-γ genes was constructed based on their sequences. Expression analyses in 10 various tissues were conducted after the croaker challenged with V. harveyi and C. irritans, respectively. Real time PCR analysis showed that the expression of LcIFN-γ was observed broadly in health individuals. After injected with V. harveyi, the 10 tissues had a higher expression of IFN-γ at the first day (1 d); only spleen, muscle, intestine, heart and skin had higher expressions after infected with C. irritans at 1 d. Major immune tissues (skin, gill, head kidney and spleen) and detoxification tissue (liver) were sampled at 0 h, 6 h, 1 d, 2 d, 3 d, 4 d, 5 d and 7 d to understand the expression trends of LcIFN-γ after challenged with C. irritans. The expressions of LcIFN-γ in skin and gill (the primary immune organs) showed a clear correlative relationship with the life cycle of C. irritans. PMID:26193669

  16. The Dynamics of Genetic Interactions between Vibrio metoecus and Vibrio cholerae, Two Close Relatives Co-Occurring in the Environment

    PubMed Central

    Orata, Fabini D.; Kirchberger, Paul C.; Méheust, Raphaël; Barlow, E. Jed; Tarr, Cheryl L.; Boucher, Yan

    2015-01-01

    Vibrio metoecus is the closest relative of Vibrio cholerae, the causative agent of the potent diarrheal disease cholera. Although the pathogenic potential of this new species is yet to be studied in depth, it has been co-isolated with V. cholerae in coastal waters and found in clinical specimens in the United States. We used these two organisms to investigate the genetic interaction between closely related species in their natural environment. The genomes of 20 V. cholerae and 4 V. metoecus strains isolated from a brackish coastal pond on the US east coast, as well as 4 clinical V. metoecus strains were sequenced and compared with reference strains. Whole genome comparison shows 86–87% average nucleotide identity (ANI) in their core genes between the two species. On the other hand, the chromosomal integron, which occupies approximately 3% of their genomes, shows higher conservation in ANI between species than any other region of their genomes. The ANI of 93–94% observed in this region is not significantly greater within than between species, meaning that it does not follow species boundaries. Vibrio metoecus does not encode toxigenic V. cholerae major virulence factors, the cholera toxin and toxin-coregulated pilus. However, some of the pathogenicity islands found in pandemic V. cholerae were either present in the common ancestor it shares with V. metoecus, or acquired by clinical and environmental V. metoecus in partial fragments. The virulence factors of V. cholerae are therefore both more ancient and more widespread than previously believed. There is high interspecies recombination in the core genome, which has been detected in 24% of the single-copy core genes, including genes involved in pathogenicity. Vibrio metoecus was six times more often the recipient of DNA from V. cholerae as it was the donor, indicating a strong bias in the direction of gene transfer in the environment. PMID:26454015

  17. The Dynamics of Genetic Interactions between Vibrio metoecus and Vibrio cholerae, Two Close Relatives Co-Occurring in the Environment.

    PubMed

    Orata, Fabini D; Kirchberger, Paul C; Méheust, Raphaël; Barlow, E Jed; Tarr, Cheryl L; Boucher, Yan

    2015-10-01

    Vibrio metoecus is the closest relative of Vibrio cholerae, the causative agent of the potent diarrheal disease cholera. Although the pathogenic potential of this new species is yet to be studied in depth, it has been co-isolated with V. cholerae in coastal waters and found in clinical specimens in the United States. We used these two organisms to investigate the genetic interaction between closely related species in their natural environment. The genomes of 20 V. cholerae and 4 V. metoecus strains isolated from a brackish coastal pond on the US east coast, as well as 4 clinical V. metoecus strains were sequenced and compared with reference strains. Whole genome comparison shows 86-87% average nucleotide identity (ANI) in their core genes between the two species. On the other hand, the chromosomal integron, which occupies approximately 3% of their genomes, shows higher conservation in ANI between species than any other region of their genomes. The ANI of 93-94% observed in this region is not significantly greater within than between species, meaning that it does not follow species boundaries. Vibrio metoecus does not encode toxigenic V. cholerae major virulence factors, the cholera toxin and toxin-coregulated pilus. However, some of the pathogenicity islands found in pandemic V. cholerae were either present in the common ancestor it shares with V. metoecus, or acquired by clinical and environmental V. metoecus in partial fragments. The virulence factors of V. cholerae are therefore both more ancient and more widespread than previously believed. There is high interspecies recombination in the core genome, which has been detected in 24% of the single-copy core genes, including genes involved in pathogenicity. Vibrio metoecus was six times more often the recipient of DNA from V. cholerae as it was the donor, indicating a strong bias in the direction of gene transfer in the environment. PMID:26454015

  18. Effect of Temperature on Growth of Vibrio paraphemolyticus and Vibrio vulnificus in Flounder, Salmon Sashimi and Oyster Meat

    PubMed Central

    Kim, Yoo Won; Lee, Soon Ho; Hwang, In Gun; Yoon, Ki Sun

    2012-01-01

    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

  19. Draft Genome Sequence of Vibrio owensii Strain SH-14, Which Causes Shrimp Acute Hepatopancreatic Necrosis Disease

    PubMed Central

    Liu, Liyuan; Xiao, Jinzhou; Xia, Xiaoming; Pan, Yingjie; Yan, Shuling

    2015-01-01

    We sequenced Vibrio owensii strain SH-14, which causes serious acute hepatopancreatic necrosis disease (AHPND) in shrimp. Sequence analysis showed a large extrachromosomal plasmid, which encoded pir toxin genes and shared highly sequence similarity with the one observed in AHPND-causing Vibrio parahaemolyticus strains. The results suggest that this plasmid appears to play an important role in shrimp AHPND. PMID:26634753

  20. Draft Genome Sequence of Vibrio owensii Strain SH-14, Which Causes Shrimp Acute Hepatopancreatic Necrosis Disease.

    PubMed

    Liu, Liyuan; Xiao, Jinzhou; Xia, Xiaoming; Pan, Yingjie; Yan, Shuling; Wang, Yongjie

    2015-01-01

    We sequenced Vibrio owensii strain SH-14, which causes serious acute hepatopancreatic necrosis disease (AHPND) in shrimp. Sequence analysis showed a large extrachromosomal plasmid, which encoded pir toxin genes and shared highly sequence similarity with the one observed in AHPND-causing Vibrio parahaemolyticus strains. The results suggest that this plasmid appears to play an important role in shrimp AHPND. PMID:26634753