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1

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

Microsoft Academic Search

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

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

1997-01-01

2

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

PubMed

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

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

2015-01-01

3

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

PubMed Central

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

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

2015-01-01

4

Elongation of exogenous fatty acids by the bioluminescent bacterium Vibrio harveyi  

SciTech Connect

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.

Byers, D.M.

1989-01-01

5

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

PubMed Central

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

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

2013-01-01

6

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

Microsoft Academic Search

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

Jennifer M. Henke; Bonnie L. Bassler

2004-01-01

7

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

PubMed Central

In a process called quorum sensing, bacteria communicate using extracellular signal molecules termed autoinducers. Two parallel quorum-sensing systems have been identified in the marine bacterium Vibrio harveyi. System 1 consists of the LuxM-dependent autoinducer HAI-1 and the HAI-1 sensor, LuxN. System 2 consists of the LuxS-dependent autoinducer AI-2 and the AI-2 detector, LuxPQ. The related bacterium, Vibrio cholerae, a human pathogen, possesses System 2 (LuxS, AI-2, and LuxPQ) but does not have obvious homologues of V. harveyi System 1. Rather, System 1 of V. cholerae is made up of the CqsA-dependent autoinducer CAI-1 and a sensor called CqsS. Using a V. cholerae CAI-1 reporter strain we show that many other marine bacteria, including V. harveyi, produce CAI-1 activity. Genetic analysis of V. harveyi reveals cqsA and cqsS, and phenotypic analysis of V. harveyi cqsA and cqsS mutants shows that these functions comprise a third V. harveyi quorum-sensing system that acts in parallel to Systems 1 and 2. Together these communication systems act as a three-way coincidence detector in the regulation of a variety of genes, including those responsible for bioluminescence, type III secretion, and metalloprotease production. PMID:15466044

Henke, Jennifer M.; Bassler, Bonnie L.

2004-01-01

8

Molecular identification of Vibrio harveyi-related isolates associated with diseased aquatic organisms  

Microsoft Academic Search

Fifty strains belonging to Vibrio harveyi, Vibrio campbellii, and the recently described Vibrio rotiferianus, were analysed using phenotypic and genomic techniques with the aim of analysing the usefulness of the different techniques for the identification of V. harveyi-related species. The species V. harveyi and V. campbellii were phenotypically indistinguishable by more than 100 phenotypic features. Thirty-nine experimental strains were phenotypically

Bruno Gomez-Gil; Sonia Soto-Rodriguez; Alejandra Garcia-Gasca; Ana Roque; Ricardo Vazquez-Juarez; Fabiano L. Thompson; Jean Swings

2004-01-01

9

Quorum Sensing in Escherichia coli, Salmonella typhimurium, and Vibrio harveyi: A New Family of Genes Responsible for Autoinducer Production  

Microsoft Academic Search

In bacteria, the regulation of gene expression in response to changes in cell density is called quorum sensing. Quorum-sensing bacteria produce, release, and respond to hormone-like molecules (autoinducers) that accumulate in the external environment as the cell population grows. In the marine bacterium Vibrio harveyi two parallel quorum-sensing systems exist, and each is composed of a sensor-autoinducer pair. V. harveyi

Michael G. Surette; Melissa B. Miller; Bonnie L. Bassler

1999-01-01

10

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

NASA Astrophysics Data System (ADS)

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.

Svenningsen, Sine Lo

11

Chitoporin from Vibrio harveyi, a Channel with Exceptional Sugar Specificity  

PubMed Central

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 × 106 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

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

2013-01-01

12

Overexpression, Purification, Characterization, and Pathogenicity of Vibrio harveyi Hemolysin VHH  

PubMed Central

Vibrio harveyi VHH hemolysin is a putative pathogenicity factor in fish. In this study, the hemolysin gene vhhA was overexpressed in Escherichia coli, and the purified VHH was characterized with regard to pH and temperature profiles, phospholipase activity, cytotoxicity, pathogenicity to flounder, and the signal peptide. PMID:16988279

Zhong, Yingbin; Zhang, Xiao-Hua; Chen, Jixiang; Chi, Zhenghao; Sun, Boguang; Li, Yun; Austin, Brian

2006-01-01

13

Negative Feedback in the Vibrio harveyi Quorum-Sensing Circuit  

NASA Astrophysics Data System (ADS)

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.

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

2010-03-01

14

Quorum sensing regulates the osmotic stress response in Vibrio harveyi.  

PubMed

Bacteria use a chemical communication process called quorum sensing to monitor cell density and to alter behavior in response to fluctuations in population numbers. Previous studies with Vibrio harveyi have shown that LuxR, the master quorum-sensing regulator, activates and represses >600 genes. These include six genes that encode homologs of the Escherichia coli Bet and ProU systems for synthesis and transport, respectively, of glycine betaine, an osmoprotectant used during osmotic stress. Here we show that LuxR activates expression of the glycine betaine operon betIBA-proXWV, which enhances growth recovery under osmotic stress conditions. BetI, an autorepressor of the V. harveyi betIBA-proXWV operon, activates the expression of genes encoding regulatory small RNAs that control quorum-sensing transitions. Connecting quorum-sensing and glycine betaine pathways presumably enables V. harveyi to tune its execution of collective behaviors to its tolerance to stress. PMID:25313392

van Kessel, Julia C; Rutherford, Steven T; Cong, Jian-Ping; Quinodoz, Sofia; Healy, James; Bassler, Bonnie L

2015-01-01

15

Transcriptional regulation of lux genes transferred into Vibrio harveyi.  

PubMed

Past work has shown that transformed Escherichia coli is not a suitable vehicle for studying the expression and regulation of the cloned luminescence (lux) genes of Vibrio harveyi. Therefore, we have used a conjugative system to transfer lux genes cloned into E. coli back into V. harveyi, where they can be studied in the parental organism. To do this, lux DNA was inserted into a broad-spectrum vector, pKT230, cloned in E. coli, and then mobilized into V. harveyi by mating aided by the conjugative plasmid pRK2013, also contained in E. coli. Transfer of the wild-type luxD gene into the V. harveyi M17 mutant by this means resulted in complementation of the luxD mutation and full restoration of luminescence in the mutant; expression of transferase activity was induced if DNA upstream of luxC preceded the luxD gene on the plasmid, indicating the presence of a strong inducible promoter. To extend the usefulness of the transfer system, the gene for chloramphenicol acetyltransferase was inserted into the pKT230 vector as a reporter. The promoter upstream of luxC was verified to be cell density regulated and, in addition, glucose repressible. It is suggested that this promoter may be the primary autoregulated promoter of the V. harveyi luminescence system. Strong termination signals on both DNA strands were recognized and are located downstream from luxE at a point complementary to the longest mRNA from the lux operon. Structural lux genes transferred back into V. harveyi under control of the luxC promoter are expressed at very high levels in V. harveyi as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis: the gene transfer system is thus useful for expression of proteins as well as for studying the regulation of lux genes in their native environment. PMID:2180915

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

1990-04-01

16

A model for signal transduction during quorum sensing in Vibrio harveyi  

NASA Astrophysics Data System (ADS)

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.

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

2009-12-01

17

Quorum sensing negatively regulates chitinase in Vibrio harveyi.  

PubMed

Quorum sensing, bacterial cell-to-cell communication, regulates the virulence of Vibrio harveyi towards different hosts. Chitinase can be considered as a virulence factor because it helps pathogenic bacteria to attach to the host and to penetrate its tissues (e.g. in case of shrimp). Here, we show that quorum sensing negatively regulates chitinase in V. harveyi. Chitinolytic activity towards natural chitin from crab shells, the synthetic chitin derivative chitin azure, and fluorogenic chitin oligomers was significantly higher in a mutant in which the quorum-sensing system is completely inactivated when compared with a mutant in which the system is maximally active. Furthermore, the addition of signal molecule containing cell-free culture fluids decreased chitinase activity in a Harveyi Autoinducer 1 and Autoinducer 2-deficient double mutant. Finally, chitinase A mRNA levels were fivefold lower in the mutant in which the quorum-sensing system is maximally active when compared with the mutant in which the system is completely inactivated. [Correction added on 25 September 2009, after first online publication: the preceding sentence was corrected from 'Finally, chitinase A mRNA levels were fivefold lower in the mutant in which the quorum-sensing system is completely inactivated when compared with the mutant in which the system is maximally active.'] We argue that this regulation might help the vibrios to switch between host-associated and free-living life styles. PMID:23765997

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

2010-02-01

18

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

PubMed

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

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

2013-01-01

19

Autoinducers Act as Biological Timers in Vibrio harveyi  

PubMed Central

Quorum sensing regulates cell density-dependent phenotypes and involves the synthesis, excretion and detection of so-called autoinducers. Vibrio harveyi strain ATCC BAA-1116 (recently reclassified as Vibrio campbellii), one of the best-characterized model organisms for the study of quorum sensing, produces and responds to three autoinducers. HAI-1, AI-2 and CAI-1 are recognized by different receptors, but all information is channeled into the same signaling cascade, which controls a specific set of genes. Here we examine temporal variations of availability and concentration of the three autoinducers in V. harveyi, and monitor the phenotypes they regulate, from the early exponential to the stationary growth phase in liquid culture. Specifically, the exponential growth phase is characterized by an increase in AI-2 and the induction of bioluminescence, while HAI-1 and CAI-1 are undetectable prior to the late exponential growth phase. CAI-1 activity reaches its maximum upon entry into stationary phase, while molar concentrations of AI-2 and HAI-1 become approximately equal. Similarly, autoinducer-dependent exoproteolytic activity increases at the transition into stationary phase. These findings are reflected in temporal alterations in expression of the luxR gene that encodes the master regulator LuxR, and of four autoinducer-regulated genes during growth. Moreover, in vitro phosphorylation assays reveal a tight correlation between the HAI-1/AI-2 ratio as input and levels of receptor-mediated phosphorylation of LuxU as output. Our study supports a model in which the combinations of autoinducers available, rather than cell density per se, determine the timing of various processes in V. harveyi populations. PMID:23110227

Anetzberger, Claudia; Reiger, Matthias; Fekete, Agnes; Schell, Ursula; Stambrau, Nina; Plener, Laure; Kopka, Joachim; Schmitt-Kopplin, Phillippe; Hilbi, Hubert; Jung, Kirsten

2012-01-01

20

Autoinducers act as biological timers in Vibrio harveyi.  

PubMed

Quorum sensing regulates cell density-dependent phenotypes and involves the synthesis, excretion and detection of so-called autoinducers. Vibrio harveyi strain ATCC BAA-1116 (recently reclassified as Vibrio campbellii), one of the best-characterized model organisms for the study of quorum sensing, produces and responds to three autoinducers. HAI-1, AI-2 and CAI-1 are recognized by different receptors, but all information is channeled into the same signaling cascade, which controls a specific set of genes. Here we examine temporal variations of availability and concentration of the three autoinducers in V. harveyi, and monitor the phenotypes they regulate, from the early exponential to the stationary growth phase in liquid culture. Specifically, the exponential growth phase is characterized by an increase in AI-2 and the induction of bioluminescence, while HAI-1 and CAI-1 are undetectable prior to the late exponential growth phase. CAI-1 activity reaches its maximum upon entry into stationary phase, while molar concentrations of AI-2 and HAI-1 become approximately equal. Similarly, autoinducer-dependent exoproteolytic activity increases at the transition into stationary phase. These findings are reflected in temporal alterations in expression of the luxR gene that encodes the master regulator LuxR, and of four autoinducer-regulated genes during growth. Moreover, in vitro phosphorylation assays reveal a tight correlation between the HAI-1/AI-2 ratio as input and levels of receptor-mediated phosphorylation of LuxU as output. Our study supports a model in which the combinations of autoinducers available, rather than cell density per se, determine the timing of various processes in V. harveyi populations. PMID:23110227

Anetzberger, Claudia; Reiger, Matthias; Fekete, Agnes; Schell, Ursula; Stambrau, Nina; Plener, Laure; Kopka, Joachim; Schmitt-Kopplin, Phillippe; Hilbi, Hubert; Jung, Kirsten

2012-01-01

21

Draft Genome Sequence of the Fish Pathogen Vibrio harveyi Strain ZJ0603  

PubMed Central

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

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

2012-01-01

22

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

PubMed

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

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

2012-12-01

23

Virulence Changes to Harveyi Clade Bacteria Infected with Bacteriophage from Vibrio owensii.  

PubMed

Vibrio owensii is one of the most virulent vibrios known being able to kill crustacean larvae at 10(2) CFU ml(-1). This study describes virulence changes to naïve strains of Vibrio harveyi and Vibrio campbellii when infected with the bacteriophage VOB from a closely related species V. owensii 47666-1. The bacteriophage from V. owensii was induced into lytic phase by using mitomycin C at 100 ng ml(-1). One strain of V. harveyi and two strains of V. campbellii from 29 tested containing no prophage were susceptible to lysogenic conversion with VOB. Virulence changes induced in Harveyi clade bacteria included the up-regulation of protein secretion, statistically significant increased haemolysin and chitinase production and increased mortality to nauplii of Penaeus monodon. No change in siderophore production was observed. Bacteriophage VOB is likely to be responsible for some of the virulence factors expressed by V. owensii. As this bacteriophage is able to infect strains of V. harveyi and V. campbellii this phage may contribute to increased virulence of other vibrios in aquaculture and in the natural environment. PMID:24426274

Busico-Salcedo, Nancy; Owens, Leigh

2013-09-01

24

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

PubMed

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

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

2014-01-01

25

The Small RNA Chaperone Hfq and Multiple Small RNAs Control Quorum Sensing in Vibrio harveyi and Vibrio cholerae  

Microsoft Academic Search

Quorum-sensing bacteria communicate with extracellular signal molecules called autoinducers. This process allows community-wide synchronization of gene expression. A screen for additional components of the Vibrio harveyi and Vibrio cholerae quorum-sensing circuits revealed the protein Hfq. Hfq mediates interactions between small, regulatory RNAs (sRNAs) and specific messenger RNA (mRNA) targets. These interactions typically alter the stability of the target transcripts. We

Derrick H. Lenz; Kenny C. Mok; Brendan N. Lilley; Rahul V. Kulkarni; Ned S. Wingreen; Bonnie L. Bassler

2004-01-01

26

Unexpected photoreactivation of Vibrio harveyi bacteria living in ionization environment  

NASA Astrophysics Data System (ADS)

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.

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

2011-05-01

27

Unexpected photoreactivation of Vibrio harveyi bacteria living in ionization environment  

SciTech Connect

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.

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

2011-05-15

28

Lead Precipitation by Vibrio harveyi: Evidence for Novel Quorum-Sensing Interactions  

PubMed Central

Three pleiotropic, quorum sensing-defective Vibrio harveyi mutants were observed to precipitate soluble Pb2+ as an insoluble compound. The compound was purified and subjected to X-ray diffraction and elemental analyses. These assays identified the precipitated compound as Pb9(PO4)6, an unusual and complex lead phosphate salt that is produced synthetically at temperatures of ca. 200°C. Regulation of the precipitation phenotype was also examined. Introduction of a luxO::kan allele into one of the mutants abolished lead precipitation, indicating that the well-characterized autoinducer 1 (AI1)-AI2 quorum-sensing system can block lead precipitation in dense cell populations. Interestingly, the V. harveyi D1 mutant, a strain defective for secretion of both AI1 and AI2, was shown to be an effective trans inhibitor of lead precipitation. This suggests that a previously undescribed V. harveyi autoinducer, referred to as AI3, can also negatively regulate lead precipitation. Experiments with heterologous bacterial populations demonstrated that many different species are capable of trans regulating the V. harveyi lead precipitation phenotype. Moreover, one of the V. harveyi mutants in this study exhibited little or no response to intercellular signals from other V. harveyi inocula but was quite responsive to some of the heterologous bacteria. Based on these observations, we propose that V. harveyi carries at least one quorum sensor that is specifically dedicated to receiving cross-species communication. PMID:14766565

Mire, Chad E.; Tourjee, Jeanette A.; O'Brien, William F.; Ramanujachary, Kandalam V.; Hecht, Gregory B.

2004-01-01

29

Disruption of quorum sensing in Vibrio harveyi by the AiiA protein of Bacillus thuringiensis  

Microsoft Academic Search

Quorum sensing is a mechanism in which bacteria coordinate the expression of certain genes in response to their population density by producing, releasing and detecting signal molecules called autoinducers. Quorum sensing is responsible for controlling a plethora of virulence genes in several bacterial pathogens. Disruption of the quorum sensing system of Vibrio harveyi has been proposed as a new anti-infective

Fangfang Bai; Yin Han; Jixiang Chen; Xiao-Hua Zhang

2008-01-01

30

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

PubMed

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

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

2014-10-01

31

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

PubMed

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 kinase on and kinase off states underpin whether a ligand will act as an antagonist or an agonist. Mutations that bias LuxN to the agonized, kinase off, 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

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

2015-01-01

32

Monitoring of Vibrio harveyi quorum sensing activity in real time during infection of brine shrimp larvae.  

PubMed

Quorum sensing, bacterial cell-to-cell communication, has been linked to the virulence of pathogenic bacteria. Indeed, in vitro experiments have shown that many bacterial pathogens regulate the expression of virulence genes by this cell-to-cell communication process. Moreover, signal molecules have been detected in samples retrieved from infected hosts and quorum sensing disruption has been reported to result in reduced virulence in different host-pathogen systems. However, data on in vivo quorum sensing activity of pathogens during infection of a host are currently lacking. We previously reported that quorum sensing regulates the virulence of Vibrio harveyi in a standardised model system with gnotobiotic brine shrimp (Artemia franciscana) larvae. Here, we monitored quorum sensing activity in Vibrio harveyi during infection of the shrimp, using bioluminescence as a read-out. We found that wild-type Vibrio harveyi shows a strong increase in quorum sensing activity early during infection. In this respect, the bacteria behave remarkably similar in different larvae, despite the fact that only half of them survive the infection. Interestingly, when expressed per bacterial cell, Vibrio harveyi showed around 200-fold higher maximal quorum sensing-regulated bioluminescence when associated with larvae than in the culture water. Finally, the in vivo quorum sensing activity of mutants defective in the production of one of the three signal molecules is consistent with their virulence, with no detectable in vivo quorum sensing activity in AI-2- and CAI-1-deficient mutants. These results indicate that AI-2 and CAI-1 are the dominant signals during infection of brine shrimp. PMID:22673627

Defoirdt, Tom; Sorgeloos, Patrick

2012-12-01

33

Interference of Cranberry Constituents in Cell–Cell Signaling System of Vibrio harveyi  

Microsoft Academic Search

Cranberry juice has long been recognized in folk medicine as a therapeutic agent, mainly in urinary track infections. It acts\\u000a as an antibiofilm agent against various pathogens. Quorum sensing is process where bacteria communicate with each other via\\u000a signal molecules known as autoinducers. This process is strongly involved in various bacterial pathological and physiological\\u000a pathways. Various strains of Vibrio harveyi

Mark Feldman; Ervin I. Weiss; Itzhak Ofek; Doron Steinberg

2009-01-01

34

The Outer Membrane Protein VhOmp of Vibrio harveyi : PoreForming Properties in Black Lipid Membranes  

Microsoft Academic Search

Vibrio harveyi is known to cause fatal vibriosis in marine animals. Here, an outer membrane protein from V. harveyi, namely, VhOmp, was isolated and functionally characterized in terms of pore-forming contact with artificial lipid membranes.\\u000a The native VhOmp exists as a trimer of a molecular weight similar to that of the porin OmpF from Escherichia coli. Reconstitution of VhOmp into

Albert Schulte; Sompong Ruamchan; Panida Khunkaewla; Wipa Suginta

2009-01-01

35

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

Microsoft Academic Search

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

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

2000-01-01

36

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

NASA Technical Reports Server (NTRS)

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.

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

1981-01-01

37

Bioluminescent assay for sphingolipid ceramide N-deacylase using Vibrio harveyi dark mutant M-17  

Microsoft Academic Search

A new bioluminescent assay method for the activity of sphingolipid ceramide N-deacylase (SCDase: EC 3.5.1.69) as well as ceramidase\\u000a (CDase: EC 3.5.1.23) was developed using bioluminescent marine bacteria. Enzymatically synthesized ceramide (N-myristoyl sphigosine,\\u000a C14:0-18:l) and commercial SCDase were used in this demonstration, and myristic (tetradecanoic, C14:0) acid produced by the\\u000a SCDase hydrolysis was quantified using Vibrio harveyi M-17, a dark

Ki Woong Cho

2008-01-01

38

Differentially expressed genes in hemocytes of Vibrio harveyi-challenged shrimp Penaeus monodon.  

PubMed

Differential Display PCR technique (DD-PCR) was used for the analysis of altered gene expression in hemocytes of Vibrio harveyi-infected Penaeus monodon. Forty-four combinations of arbitrary and oligo(dT) primers were used to screen for differentially expressed genes. A total of 79 differentially expressed bands could be identified from 33 primer combinations. These included 48 bands (61%) whose expression level increased and 31 bands (39%) decreased after V. harveyi challenge. Subsequently, forty-eight differential display fragments were successfully reamplified and cloned. A total of 267 clones were randomly selected and sequenced. The sequence analysis showed that 85 (31%) out of 267 clones were matched with sequences in the GenBank database which represented 24 different genes with known functions. Among the known genes, glucose transporter 1, interferon-related developmental regulator 1, lysozyme, profilin, SERPINB3, were selected for further confirmation of their differentially expression patterns by real-time PCR. The results showed increasing in expression level of the selected genes in shrimp hemocytes after microbial challenge suggesting the involvement of such genes in bacterial response in shrimp. The anti-lipopolysaccharide factor type 3 (ALFPm3) gene, previously reported in P. monodon (Supungul et al., 2002) was found among the up-regulated genes but diversity due to amino acid changes was observed. Increase in ALFPm3 transcripts upon V. harveyi injection is in accordance with that found in the previous study. PMID:16466635

Somboonwiwat, Kunlaya; Supungul, Premruethai; Rimphanitchayakit, Vichien; Aoki, Takashi; Hirono, Ikuo; Tassanakajon, Anchalee

2006-01-31

39

Effect of combined function of temperature and water activity on the growth of Vibrio harveyi  

PubMed Central

Vibrio harveyi is considered as a causative agent of the systemic disease, vibriosis, which occurs in many biological fields. The effects of temperatures (12.9–27.1 °C) and water activity (NaCl% 0.6%-3.4%) on V. harveyi were investigated. The behavior and growth characteristics of V. harveyi was studied and modeled. Growth curves were fitted by using Gompertz and Baranyi models, and the Baranyi model showed a better fittness. Then, the maximum growth rates (?max) and lag phase durations (LPD, ?) obtained from both Gompertz and Baranyi model were modeled as a combination function of temperature and water activity using the response surface and Arrhenius-Davey models for secondary model. The value of r2, MSE, bias and accuracy factor suggest Baranyi model has better fitness than Gompertz model. Furthermore, validation of the developed models with independent data from ComBase also shown better interrelationship between observed and predicted growth parameter when using Baranyi model. PMID:24031965

Zhou, Kang; Gui, Meng; Li, Pinglan; Xing, Shaohua; Cui, Tingting; Peng, Zhaohui

2012-01-01

40

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

PubMed

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

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

2012-08-17

41

Quorum Sensing Influences Vibrio harveyi Growth Rates in a Manner Not Fully Accounted For by the Marker Effect of Bioluminescence  

Microsoft Academic Search

BackgroundThe light-emitting Vibrios provide excellent material for studying the interaction of cellular communication with growth rate because bioluminescence is a convenient marker for quorum sensing. However, the use of bioluminescence as a marker is complicated because bioluminescence itself may affect growth rate, e.g. by diverting energy.Methodology\\/Principal FindingsThe marker effect was explored via growth rate studies in isogenic Vibrio harveyi (Vh)

Zeena E. Nackerdien; Alexander Keynan; Bonnie L. Bassler; Joshua Lederberg; David S. Thaler; Julian Rutherford

2008-01-01

42

Interference with the quorum sensing systems in a Vibrio harveyi strain alters the growth rate of gnotobiotically cultured rotifer Brachionus plicatilis  

Microsoft Academic Search

Aims: To evaluate the effect of Vibrio harveyi strains on the growth rate of the gnotobiotically cultured rotifer Brachionus plicatilis, and to establish whether quorum sensing is involved in the observed phenomena. Methods and Results: Gnotobiotic B. plicatilis sensu strictu, obtained by hatch- ing glutaraldehyde-treated amictic eggs, were used as test organisms. Challenge tests were performed with 11 V. harveyi

N. T. N. Tinh; N. D. Linh; T. K. Wood; K. Dierckens; P. Sorgeloos; P. Bossier

2007-01-01

43

The Vibrio harveyi GTPase CgtAV Is Essential and Is Associated with the 50S Ribosomal Subunit  

PubMed Central

It was previously reported that unlike the other obg/cgtA GTPases, the Vibrio harveyi cgtAV is not essential. Here we show that cgtAV was not disrupted in these studies and is, in fact, essential for viability. Depletion of CgtAV did not result in cell elongation. CgtAV is associated with the large ribosomal particle. In light of our results, we predict that the V. harveyi CgtAV protein plays a similar essential role to that seen for Obg/CgtA proteins in other bacteria. PMID:16428430

Sikora, A. E.; Zielke, R.; Datta, K.; Maddock, J. R.

2006-01-01

44

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

PubMed

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

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

2015-01-01

45

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

NASA Astrophysics Data System (ADS)

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 Michaelis—Menten 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.

Shen, Jian-Wei

2011-03-01

46

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

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

Hundenborn, Jörg; Thurig, Steffi

2013-01-01

47

Computational modeling of differences in the quorum sensing induced luminescence phenotypes of \\textit{Vibrio harveyi} and \\textit{Vibrio cholerae}  

E-print Network

\\textit{Vibrio harveyi} and \\textit{Vibrio cholerae} have quorum sensing pathways with similar design and highly homologous components including multiple small RNAs (sRNAs). However, the associated luminescence phenotypes of strains with sRNA deletions differ dramatically: in \\textit{V. harveyi}, the sRNAs act additively; however, in \\textit{V. cholerae}, the sRNAs act redundantly. Furthermore, there are striking differences in the luminescence phenotypes for different pathway mutants in \\textit{V. harveyi} and \\textit{V. cholerae}. However these differences have not been connected with the observed differences for the sRNA deletion strains in these bacteria. In this work, we present a model for quorum sensing induced luminescence phenotypes focusing on the interactions of multiple sRNAs with target mRNA. Within our model, we find that one key parameter -- the fold-change in protein concentration necessary for luminescence activation -- can control whether the sRNAs appear to act additively or redundantly. For specific parameter choices, we find that differences in this key parameter can also explain hitherto unconnected luminescence phenotypes differences for various pathway mutants in \\textit{V. harveyi} and \\textit{V. cholerae}. The model can thus provide a unifying explanation for observed differences in luminescence phenotypes and can also be used to make testable predictions for future experiments.

Andrew T Fenley; Suman K Banik; Rahul V Kulkarni

2011-01-27

48

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)

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.

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

2013-08-01

49

Parallel Quorum Sensing Systems Converge to Regulate Virulence in Vibrio cholerae  

Microsoft Academic Search

The marine bacterium Vibrio harveyi possesses two quorum sensing systems (System 1 and System 2) that regulate bioluminescence. Although the Vibrio cholerae genome sequence reveals that a V. harveyi-like System 2 exists, it does not predict the existence of a V. harveyi-like System 1 or any obvious quorum sensing-controlled target genes. In this report we identify and characterize the genes

Melissa B. Miller; Karen Skorupski; Derrick H. Lenz; Ronald K. Taylor; Bonnie L. Bassler

2002-01-01

50

Characterization of DegQVh, a Serine Protease and a Protective Immunogen from a Pathogenic Vibrio harveyi Strain? †  

PubMed Central

Vibrio harveyi is an important marine pathogen that can infect a number of aquaculture species. V. harveyi degQ (degQVh), the gene encoding a DegQ homologue, was cloned from T4, a pathogenic V. harveyi strain isolated from diseased fish. DegQVh was closely related to the HtrA family members identified in other Vibrio species and could complement the temperature-sensitive phenotype of an Escherichia coli strain defective in degP. Expression of degQVh in T4 was modulated by temperature, possibly through the ?E-like factor. Enzymatic analyses demonstrated that the recombinant DegQVh protein expressed in and purified from E. coli was an active serine protease whose activity required the integrity of the catalytic site and the PDZ domains. The optimal temperature and pH of the recombinant DegQVh protein were 50°C and pH 8.0. A vaccination study indicated that the purified recombinant DegQVh was a protective immunogen that could confer protection upon fish against infection by V. harveyi. In order to improve the efficiency of DegQVh as a vaccine, a genetic construct in the form of the plasmid pAQ1 was built, in which the DNA encoding the processed DegQVh protein was fused with the DNA encoding the secretion region of AgaV, an extracellular ?-agarase. The E. coli strain harboring pAQ1 could express and secrete the chimeric DegQVh protein into the culture supernatant. Vaccination of fish with viable E. coli expressing chimeric degQVh significantly (P < 0.001) enhanced the survival of fish against V. harveyi challenge, which was possibly due to the relatively prolonged exposure of the immune system to the recombinant antigen produced constitutively, albeit at a gradually decreasing level, by the carrier strain. PMID:18723647

Zhang, Wei-wei; Sun, Kun; Cheng, Shuang; Sun, Li

2008-01-01

51

Novel beta-lactamase genes from two environmental isolates of Vibrio harveyi.  

PubMed

Two ampicillin-resistant (Amp(r)) isolates of Vibrio harveyi, W3B and HB3, were obtained from the coastal waters of the Indonesian island of Java. Strain W3B was isolated from marine water near a shrimp farm in North Java while HB3 was from pristine seawater in South Java. In this study, novel beta-lactamase genes from W3B (bla(VHW-1)) and HB3 (bla(VHH-1)) were cloned and their nucleotide sequences were determined. An open reading frame (ORF) of 870 bp encoding a deduced protein of 290 amino acids (VHW-1) was revealed for the bla gene of strain W3B while an ORF of 849 bp encoding a 283-amino-acid protein (VHH-1) was deduced for bla(VHH-1). At the DNA level, genes for VHW-1 and VHH-1 have a 97% homology, while at the protein level they have a 91% homology of amino acid sequences. Neither gene sequence showed homology to any other beta-lactamases in the databases. The deduced proteins were found to be class A beta-lactamases bearing low levels of homology (<50%) to other beta-lactamases of the same class. The highest level of identity was obtained with beta-lactamases from Pseudomonas aeruginosa, i.e., PSE-1, PSE-4, and CARB-3, and Vibrio cholerae CARB-6. Our study showed that both strains W3B and HB3 possess an endogenous plasmid of approximately 60 kb in size. However, Southern hybridization analysis employing bla(VHW-1) as a gene probe demonstrated that the bla gene was not located in the plasmid. A total of nine ampicillin-resistant V. harveyi strains, including W3B and HB3, were examined by pulsed-field gel electrophoresis of NotI-digested genomic DNA. Despite a high level of intrastrain genetic diversity, the bla(VHW-1) probe hybridized only to an 80- or 160-kb NotI genomic fragment in different isolates. PMID:10770767

Teo, J W; Suwanto, A; Poh, C L

2000-05-01

52

Control of the Type 3 Secretion System in Vibrio harveyi by Quorum Sensing through Repression of ExsA ? ‡  

PubMed Central

The type 3 secretion system (T3SS) genes of Vibrio harveyi are activated at low cell density and repressed at high cell density by quorum sensing (QS). Repression requires LuxR, the master transcriptional regulator of QS-controlled genes. Here, we determine the mechanism underlying the LuxR repression of the T3SS system. Using a fluorescence-based cell sorting approach, we isolated V. harveyi mutants that are unable to express T3SS genes at low cell density and identified two mutations in the V. harveyi exsBA operon. While LuxR directly represses the expression of exsBA, complementation and epistasis analyses reveal that it is the repression of exsA expression, but not exsB expression, that is responsible for the QS-mediated repression of T3SS genes at high cell density. The present work further defines the genes in the V. harveyi QS regulon and elucidates a mechanism demonstrating how multiple regulators can be linked in series to direct the expression of QS target genes specifically at low or high cell density. PMID:20543047

Waters, Christopher M.; Wu, Julie T.; Ramsey, Meghan E.; Harris, Rebecca C.; Bassler, Bonnie L.

2010-01-01

53

Control of the type 3 secretion system in Vibrio harveyi by quorum sensing through repression of ExsA.  

PubMed

The type 3 secretion system (T3SS) genes of Vibrio harveyi are activated at low cell density and repressed at high cell density by quorum sensing (QS). Repression requires LuxR, the master transcriptional regulator of QS-controlled genes. Here, we determine the mechanism underlying the LuxR repression of the T3SS system. Using a fluorescence-based cell sorting approach, we isolated V. harveyi mutants that are unable to express T3SS genes at low cell density and identified two mutations in the V. harveyi exsBA operon. While LuxR directly represses the expression of exsBA, complementation and epistasis analyses reveal that it is the repression of exsA expression, but not exsB expression, that is responsible for the QS-mediated repression of T3SS genes at high cell density. The present work further defines the genes in the V. harveyi QS regulon and elucidates a mechanism demonstrating how multiple regulators can be linked in series to direct the expression of QS target genes specifically at low or high cell density. PMID:20543047

Waters, Christopher M; Wu, Julie T; Ramsey, Meghan E; Harris, Rebecca C; Bassler, Bonnie L

2010-08-01

54

Tryptophan fluorescence reveals induced folding of Vibrio harveyi acyl carrier protein upon interaction with partner enzymes.  

PubMed

We have introduced tryptophan as a local fluorescent probe to monitor the conformation of Vibrio harveyi acyl carrier protein (ACP), a small flexible protein that is unfolded at neutral pH but must undergo reversible conformational change during the synthesis and delivery of bacterial fatty acids. Consistent with known 3D structures of ACP, steady-state fluorescence and quenching experiments indicated that Trp at positions 46, 50, and 72 are buried in the hydrophobic core upon Mg(2+)-induced ACP folding, whereas residues 25 and 45 remain in a hydrophilic environment on the protein surface. Attachment of fatty acids to the phosphopantetheine prosthetic group progressively stabilized the folded conformation of all Trp-substituted ACPs, but longer chains (14:0) were less effective than medium chains (8:0) in shielding Trp from acrylamide quenching in the L46W protein. Interaction with ACP-dependent enzymes LpxA and holo-ACP synthase also caused folding of L46W; fluorescence quenching indicated proximity of Trp-45 in helix II of ACP in LpxA binding. Our results suggest that divalent cations and fatty acylation produce differing environments in the ACP core and also reveal enzyme partner-induced folding of ACP, a key feature of "natively unfolded" proteins. PMID:18773978

Gong, Huansheng; Murphy, Peter W; Langille, Gavin M; Minielly, Sarah J; Murphy, Anne; McMaster, Christopher R; Byers, David M

2008-11-01

55

Computational modeling of differences in the quorum sensing induced luminescence phenotypes of \\textit{Vibrio harveyi} and \\textit{Vibrio cholerae}  

E-print Network

\\textit{Vibrio harveyi} and \\textit{Vibrio cholerae} have quorum sensing pathways with similar design and highly homologous components including multiple small RNAs (sRNAs). However, the associated luminescence phenotypes of strains with sRNA deletions differ dramatically: in \\textit{V. harveyi}, the sRNAs act additively; however, in \\textit{V. cholerae}, the sRNAs act redundantly. Furthermore, there are striking differences in the luminescence phenotypes for different pathway mutants in \\textit{V. harveyi} and \\textit{V. cholerae}. However these differences have not been connected with the observed differences for the sRNA deletion strains in these bacteria. In this work, we present a model for quorum sensing induced luminescence phenotypes focusing on the interactions of multiple sRNAs with target mRNA. Within our model, we find that one key parameter -- the fold-change in protein concentration necessary for luminescence activation -- can control whether the sRNAs appear to act additively or redundantly. Fo...

Fenley, Andrew T; Kulkarni, Rahul V

2011-01-01

56

Synthesis and evaluation of thiazolidinedione and dioxazaborocane analogues as inhibitors of AI-2 quorum sensing in Vibrio harveyi.  

PubMed

Two focused libraries based on two types of compounds, that is, thiazolidinediones and dioxazaborocanes were designed. Structural resemblances can be found between thiazolidinediones and well-known furanone type quorum sensing (QS) inhibitors such as N-acylaminofuranones, and/or acyl-homoserine lactone signaling molecules, while dioxazaborocanes structurally resemble previously reported oxazaborolidine derivatives which antagonized autoinducer 2 (AI-2) binding to its receptor. Because of this, we hypothesized that these compounds could affect AI-2 QS in Vibrio harveyi. Although all compounds blocked QS, the thiazolidinediones were the most active AI-2 QS inhibitors, with EC(50) values in the low micromolar range. Their mechanism of inhibition was elucidated by measuring the effect on bioluminescence in a series of V. harveyi QS mutants and by DNA-binding assays with purified LuxR protein. The active compounds neither affected bioluminescence as such nor the production of AI-2. Instead, our results indicate that the thiazolidinediones blocked AI-2 QS in V. harveyi by decreasing the DNA-binding ability of LuxR. In addition, several dioxazaborocanes were found to block AI-2 QS by targeting LuxPQ. PMID:23286963

Brackman, Gilles; Al Quntar, Abed Al Aziz; Enk, Claes D; Karalic, Izet; Nelis, Hans J; Van Calenbergh, Serge; Srebnik, Morris; Coenye, Tom

2013-02-01

57

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

PubMed Central

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

Urbanczyk, Henryk; Ogura, Yoshitoshi; Hayashi, Tetsuya

2015-01-01

58

The Vibrio harveyi master quorum-sensing regulator, LuxR, a TetR-type protein is both an activator and a repressor: DNA  

E-print Network

The Vibrio harveyi master quorum-sensing regulator, LuxR, a TetR-type protein is both an activator, USA. 6 Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA. Summary Quorum sensing. The detection of these autoinducers ultimately leads to the produc- tion of LuxR, the quorum-sensing master

Bulyk, Martha L.

59

Phenotypic and Genotypic Characteristics of Vibrio Harveyi Isolated from Black Tiger Shrimp (Penaeus Monodon)  

Microsoft Academic Search

In the present study, a total of 30 luminous bacteria were successfully isolated from the hepatopancreas of tiger shrimp (Penaeus monodon) in Kedah, Terengganu and Johore. Based on the Baumann and Schubert (12) scheme, all isolates were identified as V. harveyi. Thirty biochemical and physiological tests were carried out to reveal the similarity and differentiatial phenotypes among the isolates. Although

Najiah Musa; Lee Seong Wei; Wendy Wee

2008-01-01

60

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

PubMed

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

Pholdaeng, Komsil; Pongsamart, Sunanta

2010-04-01

61

Quorum Sensing Influences Vibrio harveyi Growth Rates in a Manner Not Fully Accounted For by the Marker Effect of Bioluminescence  

PubMed Central

Background The light-emitting Vibrios provide excellent material for studying the interaction of cellular communication with growth rate because bioluminescence is a convenient marker for quorum sensing. However, the use of bioluminescence as a marker is complicated because bioluminescence itself may affect growth rate, e.g. by diverting energy. Methodology/Principal Findings The marker effect was explored via growth rate studies in isogenic Vibrio harveyi (Vh) strains altered in quorum sensing on the one hand, and bioluminescence on the other. By hypothesis, growth rate is energy limited: mutants deficient in quorum sensing grow faster because wild type quorum sensing unleashes bioluminescence and bioluminescence diverts energy. Findings reported here confirm a role for bioluminescence in limiting Vh growth rate, at least under the conditions tested. However, the results argue that the bioluminescence is insufficient to explain the relationship of growth rate and quorum sensing in Vh. A Vh mutant null for all genes encoding the bioluminescence pathway grew faster than wild type but not as fast as null mutants in quorum sensing. Vh quorum sensing mutants showed altered growth rates that do not always rank with their relative increase or decrease in bioluminescence. In addition, the cell-free culture fluids of a rapidly growing Vibrio parahaemolyticus (Vp) strain increased the growth rate of wild type Vh without significantly altering Vh's bioluminescence. The same cell-free culture fluid increased the bioluminescence of Vh quorum mutants. Conclusions/Significance The effect of quorum sensing on Vh growth rate can be either positive or negative and includes both bioluminescence-dependent and independent components. Bioluminescence tends to slow growth rate but not enough to account for the effects of quorum sensing on growth rate. PMID:18301749

Nackerdien, Zeena E.; Keynan, Alexander; Bassler, Bonnie L.; Lederberg, Joshua; Thaler, David S.

2008-01-01

62

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

PubMed Central

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 µg l?1 glucose (equivalent to 0–16.0 mg glucose C kg?1 soil) with the detection limit of 10 µg 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 2.9±2.2 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

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

2012-01-01

63

Assimilable organic carbon (AOC) in soil water extracts using Vibrio harveyi BB721 and its implication for microbial biomass.  

PubMed

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 µg l(-1) glucose (equivalent to 0-16.0 mg glucose C kg(-1) soil) with the detection limit of 10 µg 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 2.9±2.2 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

Ma, Jincai; Ibekwe, A Mark; Wang, Haizhen; Xu, Jianming; Leddy, Menu; Yang, Ching-Hong; Crowley, David E

2012-01-01

64

Effect of Lactobacillus plantarum isolated from digestive tract of wild shrimp on growth and survival of white shrimp (Litopenaeus vannamei) challenged with Vibrio harveyi.  

PubMed

Two hundred and two strains of lactic acid bacteria (LAB) isolated from digestive tracts of cultivated and wild adult shrimp, including Litopenaeus vannamei, Metapenaeus brevicornis and Penaeus merguiensis were selected based on their antibacterial activity against Vibrio harveyi. LAB strain of MRO3.12 exhibiting highest reduction of V. harveyi was identified as Lactobacillus plantarum MRO3.12 based on the nucleotide sequence of its 16S rDNA, which showed 99% (780/786 bp) homology to L. plantarum strain L5 (GenBank accession number DQ 239698.1). Co-cultivation of V. harveyi and L. plantarum MRO3.12 showed complete reduction of V. harveyi at 24 h under aerobic and anaerobic conditions, whereas L. plantarum increased from 5.29 to 9.47 log CFU ml(-1). After 6-week feeding trial with L. plantarum supplemented diet, white shrimp (L. vannamei) exhibited significant differences (p < 0.05) in relative growth rate (% RGR), feed conversion ratio (FCR) and survival compared to the control group fed with non-supplemented diet. LAB-fed group showed 98.89% survival, whereas only 68.89% survival was observed in the control group. LAB from the digestive tract of probiotic-fed shrimp showed higher level of 5.0 ± 0.14 log CFU/g than the non-supplemented ones (3.34 ± 0.21 log CFU/g). However, total bacterial and non-fermenting vibrios counts decreased in shrimps fed on L. plantarum. Ten days after infection with V. harveyi (5.3-5.5 log CFU ml(-1)), significant survival (p < 0.05) of 77% was observed in LAB supplemented shrimp, while only 67% survival was observed in the control. PMID:22126856

Kongnum, Khanitta; Hongpattarakere, Tipparat

2012-01-01

65

Description of a bacteriocinogenic plasmid in Beneckea harveyi.  

PubMed Central

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

McCall, J O; Sizemore, R K

1979-01-01

66

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

PubMed Central

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

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

2012-01-01

67

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

PubMed Central

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

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

1979-01-01

68

Chemical and structural characterization of hydroxamate siderophore produced by marine Vibrio harveyi  

Microsoft Academic Search

In the present study, 22 different bacteria were isolated from open ocean water from the Gulf of Mannar, India. Of the 22\\u000a isolates, 4 were identified as Vibrio spp. (VM1, VM2, VM3 and VM4) and found to produce siderophores (iron-binding chelators) under iron-limited conditions. Different\\u000a media were found to have an influence on siderophore production. Maximum siderophore production was observed

R. M. Murugappan; A. Aravinth; M. Karthikeyan

2011-01-01

69

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

E-print Network

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

Hammock, Bruce D.

70

Preliminary assessment of mutagenic and anti-mutagenic potential of some aminoalkanolic derivatives of xanthone by use of the Vibrio harveyi assay.  

PubMed

The Vibrio harveyi assay was used to evaluate mutagenic and anti-mutagenic effects of four new aminoalkanolic derivatives of xanthone with anticonvulsant activity, to select the potentially safe compounds for further in vivo studies in animal models. The study showed that at a concentration of 40 ng/ml the test compounds were not mutagenic. Additionally, two of the investigated compounds, namely the (R,S)-N-methyl-1-amino-2-propanol derivative of 6-methoxyxanthone (compound III) and the (R)-N-methyl-2-amino-1-butanol derivative of 7-chloroxanthone (compound IV) were strong inhibitors of the mutagenicity induced by 4-nitroquinoline-N-oxide (4-NQO) in V. harveyi strains BB7M and BB7XM. The inhibition percentages for compound IV were 49 (in BB7M) and 69 (in BB7XM), whereas for compound III these percentages were 47 (in BB7M) and 42 (in BB7XM), respectively. The present study demonstrates that four bioactive derivatives of xanthone display no mutagenic activity in the V. harveyi assay. In addition, compounds III and IV demonstrated considerable anti-mutagenic activity in this test. Based on the results obtained here, these compounds could be selected for further studies in animal models, while compounds III and IV should be tested further for their anti-mutagenic properties. PMID:24769486

S?oczy?ska, Karolina; Waszkielewicz, Anna Maria; Marona, Henryk

2014-07-01

71

Identification of immune-related genes from kidney and spleen of turbot, Psetta maxima (L.), by suppression subtractive hybridization following challenge with Vibrio harveyi.  

PubMed

Suppression subtractive hybridization was used to investigate the response of turbot, Psetta maxima (L.), to Vibrio harveyi, by using a cDNA library constructed from artificially infected turbot kidney and spleen mRNA. Forty-nine expressed sequence tags were obtained. Several immune system genes were identified, including a major histocompatibility complex (MHC) class Ia gene and a heat shock protein 70 gene. Some signalling molecules were also present in the cDNA libraries, including src-family tyrosine kinase SCK, sgk-1 serine-threonine protein kinase and amyloid precursor-like protein 2. The full length of MHC class Ia cDNA was cloned from turbot cDNA by rapid amplification of cDNA ends polymerase chain reaction. The nucleotide sequence of turbot MHC class Ia has been submitted to GenBank with accession number EF032639. The turbot MHC class Ia cDNA has an open reading frame encoding 354 amino acids, and the deduced amino acid sequence of turbot MHC class Ia has 68%, 54%, 51%, 52%, 57%, 33%, 29% and 29% identities to those of olive flounder, medaka, rainbow trout, Atlantic cod, tiger puffer, chicken, mouse and human, respectively. Quantitative reverse transcriptase-PCR was performed for the MHC class Ia gene, and it was revealed that the expression level of the MHC class Ia gene in V. harveyi-challenged turbot increased to fourfold that of the controls. PMID:18577100

Wang, C; Zhang, X-H; Jia, A; Chen, J; Austin, B

2008-07-01

72

Evolution of tolerance to PCBs and susceptibility to a bacterial pathogen (Vibrio harveyi) in Atlantic killifish (Fundulus heteroclitus) from New Bedford (MA, USA) harbor  

PubMed Central

A population of the non-migratory estuarine fish Fundulus heteroclitus (Atlantic killifish) resident to New Bedford (NB), Massachusetts, USA, an urban harbor highly contaminated with polychlorinated biphenyls (PCBs), demonstrates recently evolved tolerance to some aspects of PCB toxicity. PCB toxicology, ecological theory, and some precedence supported expectations of increased susceptibility to pathogens in NB killifish. However, laboratory bacterial challenges of the marine pathogen Vibrio harveyi to wild fish throughout the reproductive season and to their mature laboratory-raised progeny demonstrated comparable survival by NB and reference killifish, and improved survival by NB males. These results are inconsistent with hypothesized tradeoffs of adaptation, and suggest that evolved tolerance in NB killifish may include mechanisms that minimize the immunosuppressive effects of PCBs. Compensatory strategies of populations persisting in highly contaminated environments provide a unique perspective for understanding the long-term ecological effects of toxic chemicals. PMID:19110353

Nacci, Diane; Huber, Marina; Champlin, Denise; Jayaraman, Saro; Cohen, Sarah; Gauger, Eric; Fong, Allison; Gomez-Chiarri, Marta

2009-01-01

73

Draft Genome Sequence of the Oyster Larval Probiotic Bacterium Vibrio sp. Strain OY15  

PubMed Central

We report the draft genome sequence of Vibrio sp. strain OY15, a Gram-negative marine bacterium isolated from an oyster (Crassostrea virginica) digestive tract and shown to possess probiotic activity. The availability of this genome sequence will facilitate the study of the mechanisms of probiotic activity as well as virulence capacity. PMID:25278542

Schott, Eric J.

2014-01-01

74

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

Microsoft Academic Search

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

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

2000-01-01

75

Shuttle cloning vectors for the marine bacterium Vibrio parahaemolyticus.  

PubMed

Two cosmid cloning vectors containing lambda cos sequences and a 42-base-pair multipurpose cloning sequence were constructed. pAD22 also contains a 1.4-kilobase TRP-ARS fragment from Saccharomyces cerevisiae. These cosmids transformed Escherichia coli and S. cerevisiae cells and could be mobilized into Vibrio parahaemolyticus strains with a conjugative plasmid, pRK2013. The cosmid pAD22 was genetically and structurally stable during passage through V. parahaemolyticus and E. coli strains. PMID:6094492

Datta, A R; Kaper, J B; MacQuillan, A M

1984-11-01

76

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

PubMed

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

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

2014-11-01

77

Individual and Combined Roles of the Master Regulators AphA and LuxR in Control of the Vibrio harveyi Quorum-Sensing Regulon  

PubMed Central

Bacteria use a chemical communication process called quorum sensing to control transitions between individual and group behaviors. In the Vibrio harveyi quorum-sensing circuit, two master transcription factors, AphA and LuxR, coordinate the quorum-sensing response. Here we show that AphA regulates 167 genes, LuxR regulates 625 genes, and they coregulate 77 genes. LuxR strongly controls genes at both low cell density and high cell density, suggesting that it is the major quorum-sensing regulator. In contrast, AphA is absent at high cell density and acts to fine-tune quorum-sensing gene expression at low cell density. We examined two loci as case studies of coregulation by AphA and LuxR. First, AphA and LuxR directly regulate expression of the genes encoding the quorum-regulatory small RNAs Qrr2, Qrr3, and Qrr4, the consequence of which is a specifically timed transition between the individual and the group life-styles. Second, AphA and LuxR repress type III secretion system genes but at different times and to different extents. The consequence of this regulation is that type III secretion is restricted to a peak at mid-cell density. Thus, the asymmetric production of AphA and LuxR coupled with differences in their strengths and timing of target gene regulation generate a precise temporal pattern of gene expression. PMID:23204455

van Kessel, Julia C.; Rutherford, Steven T.; Shao, Yi; Utria, Alan F.

2013-01-01

78

Complete Genome Sequence of Vibrio vulnificus 93U204, a Bacterium Isolated from Diseased Tilapia in Taiwan  

PubMed Central

Vibrio vulnificus 93U204 is a bacterium isolated from a moribund tilapia collected in Kaohsiung, Taiwan. Here, we report the complete genome sequence of this bacterium to facilitate the investigation of its pathogenicity and for comparative analyses with human-pathogenic strains within the same species. PMID:25278541

Lo, Wen-Sui; Chen, Hwajiun; Chen, Chun-Yao

2014-01-01

79

Complete Genome Sequence of Vibrio vulnificus 93U204, a Bacterium Isolated from Diseased Tilapia in Taiwan.  

PubMed

Vibrio vulnificus 93U204 is a bacterium isolated from a moribund tilapia collected in Kaohsiung, Taiwan. Here, we report the complete genome sequence of this bacterium to facilitate the investigation of its pathogenicity and for comparative analyses with human-pathogenic strains within the same species. PMID:25278541

Lo, Wen-Sui; Chen, Hwajiun; Chen, Chun-Yao; Kuo, Chih-Horng

2014-01-01

80

ORIGINAL ARTICLE Interference with the quorum sensing systems in a Vibrio  

E-print Network

ORIGINAL ARTICLE Interference with the quorum sensing systems in a Vibrio harveyi strain alters is influenced Keywords Brachionus, brominated furanone, quorum sensing, Vibrio harveyi. Correspondence Nguyen whether quorum sensing is involved in the observed phenomena. Methods and Results: Gnotobiotic B

Wood, Thomas K.

81

Cloning, expression, and characterization of a chitinase gene from the Antarctic psychrotolerant bacterium Vibrio sp. strain Fi:7  

Microsoft Academic Search

A marine psychrotolerant bacterium from the Antarctic Ocean showing high chitinolytic activity on chitin agar at 5°C was isolated. The sequencing of the 16S rRNA indicates taxonomic affiliation of the isolate Fi:7 to the genus Vibrio. By chitinase activity screening of a genomic DNA library of Vibrio sp. strain Fi:7 in Escherichia coli, three chitinolytic clones could be isolated. Sequencing

Anne Bendt; Heike Hüller; Ulrike Kammel; Elisabeth Helmke; Thomas Schweder

2001-01-01

82

A marine bacterium, Micrococcus MCCB 104, antagonistic to vibrios in prawn larval rearing systems.  

PubMed

A marine bacterium, Micrococcus MCCB 104, isolated from hatchery water, demonstrated extracellular antagonistic properties against Vibrio alginolyticus, V. parahaemolyticus, V. vulnificus, V. fluviallis, V. nereis, V. proteolyticus, V. mediterranei, V cholerae and Aeromonas sp., bacteria associated with Macrobrachium rosenbergii larval rearing systems. The isolate inhibited the growth of V. alginolyticus during co-culture. The antagonistic component of the extracellular product was heat-stable and insensitive to proteases, lipase, catalase and alpha-amylase. Micrococcus MCCB 104 was demonstrated to be non-pathogenic to M. rosenbergii larvae. PMID:16465832

Jayaprakash, N S; Pai, S Somnath; Anas, A; Preetha, R; Philip, Rosamma; Singh, I S Bright

2005-12-30

83

Vibrio xiamenensis sp. nov., a cellulase-producing bacterium isolated from mangrove soil.  

PubMed

A taxonomic study was carried out on a cellulase-producing bacterium, strain G21(T), isolated from mangrove soil in Xiamen, Fujian province, China. Cells were Gram-negative, slightly curved rods, motile with a single polar flagellum. The strain grew at 15-40 °C and in 0.5-10% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain G21(T) belonged to the genus Vibrio and formed a clade with Vibrio furnissii ATCC 350116(T) (97.4% sequence similarity), V. fluvialis LMG 7894(T) (97.1%) and V. ponticus CECT 5869(T) (96.1%). However, multilocus sequence analysis (using rpoA, recA, mreB, gapA, gyrB and pyrH sequences) and DNA-DNA hybridization experiments indicated that the strain was distinct from the closest related Vibrio species. Additionally, strain G21(T) could be differentiated from them phenotypically by the ability to grow in 10% NaCl but not on TCBS plates, its enzyme activity spectrum, citrate utilization, oxidization of various carbon sources, hydrolysis of several substrates and its cellular fatty acid profile. The G+C content of the genomic DNA was 46.0 mol%. The major cellular fatty acids were summed feature 3 (C(16:1)?7c and/or iso-C(15:0) 2-OH), C(16:0) and C(18:1)?7c. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol, with trace amounts of diphosphatidylglycerol. The predominant quinones were Q-8 and Q-7. Based on phylogenetic, phenotypic and chemotaxonomic characteristics and DNA-DNA hybridization analysis, it is concluded that strain G21(T) represents a novel species of the genus Vibrio, for which the name Vibrio xiamenensis sp. nov. is proposed. The type strain is G21(T) (?=?DSM 22851(T) ?=?CGMCC 1.10228(T)). PMID:22039001

Gao, Zhao-Ming; Xiao, Jing; Wang, Xing-Na; Ruan, Ling-Wei; Chen, Xiu-Lan; Zhang, Yu-Zhong

2012-08-01

84

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

PubMed

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

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

2014-12-01

85

Biochemical properties of a new ?-carbonic anhydrase from the human pathogenic bacterium, Vibrio cholerae.  

PubMed

Abstract Vibrio cholerae, a Gram-negative bacterium, is the causative agent of cholera and colonizes the upper small intestine where sodium bicarbonate is present at a high concentration. Sodium bicarbonate is a potential inducer of virulence gene expression. Bacteria can increase cytosolic bicarbonate levels through the existence of transporter family proteins or through the action of metalloenzymes, called carbonic anhydrases (CAs, EC 4.2.1.1). Vibrio cholerae, lacking of transporter proteins in its genome, utilizes the CA system to accumulate bicarbonate into the cell suggesting a pivotal role of this metalloenzymes in the microbial virulence. Here, we report for the first time the characterization of the ?-CA of V. cholerae (VchCA), which has been identified by translated genome inspection. The ?-CA encoding gene was cloned and expressed in Escherichia coli and the recombinant protein purified to homogeneity. This investigation aimed to study the biochemical properties of VchCA and to provide preliminary insights in the field of this pathogen virulence. VchCA has a low esterase activity with 4-nitrophenyl acetate as substrate, and a high activity for the hydration of CO2 to bicarbonate. PMID:23321008

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

2014-02-01

86

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

PubMed

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

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

2015-01-14

87

Homologues of insecticidal toxin complex genes within a genomic island in the marine bacterium Vibrio parahaemolyticus.  

PubMed

Three insecticidal toxin complex (tc)-like genes were identified in Vibrio parahaemolyticus 13-028/A3, which can cause acute hepatopancreatic necrosis disease in penaeid shrimp. The three genes are a tcdA-like gene (7710 bp), predicted to code for a 284-kDa protein; a tcdB-like gene (4272 bp), predicted to code for a 158-kDa protein; and a tccC3-like gene (2916 bp), predicted to encode a 107-kDa protein. All three predicted proteins contain conserved domains that are characteristic of their respective Tc proteins. By RT-PCR, all three tc-like genes were found to be expressed in this bacterium. Through genome walking and the use of PCR to join contigs surrounding these three genes, a genomic island (87 712 bp, named tc-GIvp) was found on chromosome II localized next to the tRNA Gly. The GC content of this island, which is not found in other Vibrio species, is 40%. The tc-GIvp is characterized to have 60 ORFs encoding regulatory or virulence factors. These include a type 6 secretion protein VgrG, EAL domain-containing proteins, fimbriae subunits and assembly proteins, invasin-like proteins, peptidoglycan-binding proteins, and Tc proteins. The tc-GIvp also contains 21 transposase genes, suggesting that it was acquired through horizontal transfer from other organisms. PMID:25272969

Tang, Kathy F J; Lightner, Donald V

2014-10-01

88

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

PubMed

An ?-carbonic anhydrase (CA, EC 4.2.1.1) has been recently cloned and characterized in the human pathogenic bacterium Vibrio cholerae, denominated VchCA (Del Prete et al. J. Med. Chem.2012, 55, 10742). This enzyme shows a good catalytic activity for the CO2 hydration reaction, comparable to that of the human (h) isoform hCA I. Many inorganic anions and several small molecules were investigated as VchCA inhibitors. Inorganic anions such as cyanate, cyanide, hydrogen sulfide, hydrogen sulfite, and trithiocarbonate were effective VchCA inhibitors with inhibition constants in the range of 33-88?M. Other effective inhibitors were diethyldithiocarbamate, sulfamide, sulfamate, phenylboronic acid and phenylarsonic acid, with KIs of 7-43?M. Halides (bromide, iodide), bicarbonate and carbonate were much less effective VchCA inhibitors, with KIs in the range of 4.64-28.0mM. The resistance of VchCA to bicarbonate inhibition may represent an evolutionary adaptation of this enzyme to living in an environment rich in this ion, such as the gastrointestinal tract, as bicarbonate is a virulence enhancer of this bacterium. PMID:23414807

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

2013-03-15

89

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

NASA Astrophysics Data System (ADS)

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 1.4×107 cells ml-1, while cells died within 2 days of incubation when the bacterial concentration was 1.5×106 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.

Seong, Kyeong Ah; Jeong, Hae Jin

2011-06-01

90

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

PubMed Central

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

Harwood-Sears, V; Gordon, A S

1990-01-01

91

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

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

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

2014-01-01

92

The Vibrio campbellii quorum sensing signals have a different impact on virulence of the bacterium towards different crustacean hosts.  

PubMed

Pathogenic bacteria communicate with small signal molecules in a process called quorum sensing, and they often use different signal molecules to regulate virulence gene expression. Vibrio campbellii, one of the major pathogens of aquatic organisms, regulates virulence gene expression by a three channel quorum sensing system. Here we show that although they use a common signal transduction cascade, the signal molecules have a different impact on the virulence of the bacterium towards different hosts, i.e. the brine shrimp Artemia franciscana and the commercially important giant freshwater prawn Macrobrachium rosenbergii. These results suggest that the use of multiple types of signal molecules to regulate virulence gene expression is one of the features that allow bacteria to infect different hosts. Our findings emphasize that it is highly important to study the efficacy of quorum sensing inhibitors as novel biocontrol agents under conditions that are as close as possible to the clinical situation. PMID:24055027

Pande, Gde Sasmita Julyantoro; Natrah, Fatin Mohd Ikhsan; Sorgeloos, Patrick; Bossier, Peter; Defoirdt, Tom

2013-12-27

93

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

PubMed

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

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

2014-12-01

94

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

PubMed Central

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

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

1972-01-01

95

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

PubMed Central

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

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

96

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

PubMed

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

Charbit, A; Autret, N

1998-01-01

97

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

PubMed

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

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

2007-11-01

98

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

PubMed

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

Villa, Sara; Vighi, Marco; Finizio, Antonio

2014-08-01

99

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

PubMed Central

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

Schleicher, Tyler R.; Nyholm, Spencer V.

2011-01-01

100

Production and sequence validation of a complete full length ORF collection for the pathogenic bacterium Vibrio cholerae  

PubMed Central

Cholera, an infectious disease with global impact, is caused by pathogenic strains of the bacterium Vibrio cholerae. High-throughput functional proteomics technologies now offer the opportunity to investigate all aspects of the proteome, which has led to an increased demand for comprehensive protein expression clone resources. Genome-scale reagents for cholera would encourage comprehensive analyses of immune responses and systems-wide functional studies that could lead to improved vaccine and therapeutic strategies. Here, we report the production of the FLEXGene clone set for V. cholerae O1 biovar eltor str. N16961: a complete-genome collection of ORF clones. This collection includes 3,761 sequence-verified clones from 3,887 targeted ORFs (97%). The ORFs were captured in a recombinational cloning vector to facilitate high-throughput transfer of ORF inserts into suitable expression vectors. To demonstrate its application, ?15% of the collection was transferred into the relevant expression vector and used to produce a protein microarray by transcribing, translating, and capturing the proteins in situ on the array surface with 92% success. In a second application, a method to screen for protein triggers of Toll-like receptors (TLRs) was developed. We tested in vitro-synthesized proteins for their ability to stimulate TLR5 in A549 cells. This approach appropriately identified FlaC, and previously uncharacterized TLR5 agonist activities. These data suggest that the genome-scale, fully sequenced ORF collection reported here will be useful for high-throughput functional proteomic assays, immune response studies, structure biology, and other applications. PMID:18337508

Rolfs, Andreas; Montor, Wagner R.; Yoon, Sang Sun; Hu, Yanhui; Bhullar, Bhupinder; Kelley, Fontina; McCarron, Seamus; Jepson, Daniel A.; Shen, Binghua; Taycher, Elena; Mohr, Stephanie E.; Zuo, Dongmei; Williamson, Janice; Mekalanos, John; LaBaer, Joshua

2008-01-01

101

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

PubMed Central

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

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

1994-01-01

102

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

PubMed Central

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

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

2014-01-01

103

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

PubMed

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 60°C 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

Umemoto, Yoshiaki; Shibata, Toshiyuki; Araki, Toshiyoshi

2012-02-01

104

Prevention of quorum-sensing-mediated biofilm development and virulence factors production in Vibrio spp. by curcumin.  

PubMed

The increasing occurrence of disease outbreaks caused by Vibrio spp. and the emergence of antibiotic resistance has led to a growing interest in finding alternative strategies to prevent vibriosis. Since the pathogenicity of vibrios is controlled in part by quorum-sensing (QS) system, interfering with this mechanism would prevent the pathogenicity of vibrios without developing resistance. Hence, a non-toxic phytochemical curcumin from Curcuma longa was assessed for its potential in reducing the production of QS-dependent virulence factors in Vibrio spp. The obtained results evidenced 88% reduction in bioluminescence of Vibrio harveyi by curcumin. Further, curcumin exhibited a significant inhibition in alginate, exopolysaccharides, motility, biofilm development and other virulence factors production in Vibrio parahaemolyticus, Vibrio vulnificus and V. harveyi. In in vivo analysis, curcumin enhanced the survival rate of Artemia nauplii up to 67% against V. harveyi infection by attenuating its QS-mediated virulence. PMID:23354447

Packiavathy, Issac Abraham Sybiya Vasantha; Sasikumar, Pitchaikani; Pandian, Shunmugiah Karutha; Veera Ravi, Arumugam

2013-12-01

105

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

PubMed

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

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

2014-10-21

106

Multiple regulators control capsular polysaccharide production in Vibrio parahaemolyticus.  

PubMed

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 approximately 10-fold-enhanced transcription in the OP (opaR+) strain compared to a TR (deltaopaR) 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 deltaopaR 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 TR strains and primarily OpaR dependent in OP strains. Thus, a network of positive and negative regulators modulates CPS production in V. parahaemolyticus. PMID:12949095

Güvener, Zehra Tüzün; McCarter, Linda L

2003-09-01

107

Multiple Regulators Control Capsular Polysaccharide Production in Vibrio parahaemolyticus  

PubMed Central

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

Güvener, Zehra Tüzün; McCarter, Linda L.

2003-01-01

108

Genomic taxonomy of vibrios  

PubMed Central

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

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

2009-01-01

109

Luciferase-dependent oxygen consumption by bioluminescent vibrios  

SciTech Connect

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.

Makemson, J.C.

1986-02-01

110

Polysiphonia harveyi, WNC2005-126  

NSDL National Science Digital Library

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

Freshwater, Wilson

2008-03-07

111

Inhibitory activity of probiotic Bacillus subtilis UTM 126 against vibrio species confers protection against vibriosis in juvenile shrimp (Litopenaeus vannamei).  

PubMed

The bacterial strain Bacillus subtilis UTM 126 produced antimicrobial activity against pathogenic Vibrio species, including V. alginolyticus, V. parahaemolyticus, and V. harveyi. The probiotic effect of B. subtilis was tested by feeding juvenile shrimp (Litopenaeus vannamei) food supplemented with B. subtilis (10(5 )CFU/g) for 28 days before an immersion challenge with V. harveyi at 10(5 )CFU/mL for 24 h. The treatment with B. subtilis UTM 126 decreased final mortality to 18.25%, compared with 51.75% in the control group. Bacillus subtilis UTM 126 has potential applications for controlling pathogenic V. harveyi in shrimp aquaculture. PMID:17680306

Balcázar, José Luis; Rojas-Luna, Tyrone

2007-11-01

112

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...

113

21 CFR 866.3930 - Vibrio cholerae serological reagents.  

Code of Federal Regulations, 2011 CFR

...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 electrolyte (salts) depletion, and by vomiting,...

2011-04-01

114

21 CFR 866.3930 - Vibrio cholerae serological reagents.  

Code of Federal Regulations, 2013 CFR

...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 electrolyte (salts) depletion, and by vomiting,...

2013-04-01

115

21 CFR 866.3930 - Vibrio cholerae serological reagents.  

...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 electrolyte (salts) depletion, and by vomiting,...

2014-04-01

116

21 CFR 866.3930 - Vibrio cholerae serological reagents.  

Code of Federal Regulations, 2010 CFR

...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 electrolyte (salts) depletion, and by vomiting,...

2010-04-01

117

21 CFR 866.3930 - Vibrio cholerae serological reagents.  

Code of Federal Regulations, 2012 CFR

...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 electrolyte (salts) depletion, and by vomiting,...

2012-04-01

118

The Lipid A from Vibrio fischeri Lipopolysaccharide A UNIQUE STRUCTURE BEARING A PHOSPHOGLYCEROL MOIETY*S  

E-print Network

, Novato, California 94945 Vibrio fischeri, a bioluminescent marine bacterium, exists in an exclusive the ability of E. scolopes to recognize its symbiotic partner. The bioluminescent bacterium Vibrio fischeri bacteria. The selection process that leads to the exclusive symbiotic relationship between V. fischeri

McFall-Ngai, Margaret

119

Draft Genome Sequence of Vibrio mimicus Strain CAIM 602T  

PubMed Central

Vibrio mimicus is a Gram-negative bacterium associated with gastrointestinal diseases in humans around the world. We report the complete genome sequence of the Vibrio mimicus strain CAIM 602T (CDC1721-77, LMG 7896T, ATCC 33653T). PMID:23516211

Guardiola-Avila, Iliana; Acedo-Felix, Evelia; Yepiz-Plascencia, Gloria; Sifuentes-Romero, Itzel

2013-01-01

120

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

PubMed Central

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

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

1999-01-01

121

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

PubMed

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

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

1999-06-01

122

Structure, gene regulation and environmental response of flagella in Vibrio  

PubMed Central

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

Zhu, Shiwei; Kojima, Seiji; Homma, Michio

2013-01-01

123

Vibrio parahaemolyticus  

MedlinePLUS

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

124

Distribution and ecology of Vibrio vulnificus and other lactose-fermenting marine vibrios in coastal waters of the southeastern United States.  

PubMed Central

Water, sediment, plankton, and animal samples from five coastal sites from North Carolina to Georgia were sampled for their lactose-fermenting vibrio populations. Over 20% of all vibrios tested were sucrose negative and o-nitrophenyl-beta-D-galactopyranoside (ONPG) positive, suggesting identification as the human pathogen Vibrio vulnificus. These vibrios were isolated from all sample sites and sources (water, sediment, plankton, and animals). Correlations with several of 19 environmental parameters monitored at each site were found for total vibrios. The presence of ONPG-positive, sucrose-negative vibrios was correlated with hydrocarbon levels in the water and, in the case of plankton samples, with salinity. A total of 279 sucrose-negative, ONPG-positive isolates were subjected to numerical taxonomic analysis, which resulted in three major clusters. Cluster I corresponded to and included 11 reference strains of V. vulnificus. Cluster II contained the largest number (133) of isolates, of which the great majority were bioluminescent. Although having a resemblance to V. harveyi, the isolates were ONPG positive and many were H2S positive. Cluster III consisted of strains similar to the group F vibrios (V. fluvialis). Of all of the isolates, 55% were luminescent, of which over 20% were lethal when injected into mice. Problems involved in detecting lactose fermentation among marine vibrios and the potential pathogenicity of these organisms are discussed. PMID:7159083

Oliver, J D; Warner, R A; Cleland, D R

1982-01-01

125

Vibrios dominate as culturable nitrogen-fixing bacteria of the Brazilian coral Mussismilia hispida.  

PubMed

Taxonomic characterization was performed on the putative N(2)-fixing microbiota associated with the coral species Mussismilia hispida, and with its sympatric species Palythoa caribaeorum, P. variabilis, and Zoanthus solanderi, off the coast of São Sebastião (São Paulo State, Brazil). The 95 isolates belonged to the Gammaproteobacteria according to the 16S rDNA gene sequences. In order to identify the isolates unambiguously, pyrH gene sequencing was carried out. The majority of the isolates (n = 76) fell within the Vibrio core group, with the highest gene sequence similarity being towards Vibrio harveyi and Vibrio alginolyticus. Nineteen representative isolates belonging to V. harveyi (n = 7), V. alginolyticus (n = 8), V. campbellii (n = 3), and V. parahaemolyticus (n = 1) were capable of growing six successive times in nitrogen-free medium and some of them showed strong nitrogenase activity by means of the acetylene reduction assay (ARA). It was concluded that nitrogen fixation is a common phenotypic trait among Vibrio species of the core group. The fact that different Vibrio species can fix N(2) might explain why they are so abundant in the mucus of different coral species. PMID:18678453

Chimetto, Luciane A; Brocchi, Marcelo; Thompson, Cristiane C; Martins, Roberta C R; Ramos, Heloiza R; Thompson, Fabiano L

2008-09-01

126

Vibrio communis sp. nov., isolated from the marine animals Mussismilia hispida, Phyllogorgia dilatata, Palythoa caribaeorum, Palythoa variabilis and Litopenaeus vannamei.  

PubMed

Eight Vibrio isolates originating from the marine corals Mussismilia hispida and Phyllogorgia dilatata and the zoanthids Palythoa caribaeorum and Palythoa variabilis in Brazil and the Pacific white shrimp (Litopenaeus vannamei) in Ecuador were studied by means of a polyphasic approach. The novel isolates formed a tight monophyletic group in the genus Vibrio and were closely related to species of the Vibrio harveyi group, to which they showed more than 99?% 16S rRNA gene sequence similarity. Analysis based on concatenated sequences of the following seven genes, 16S rRNA, gyrB, recA, rpoA, topA, pyrH and mreB (5633 bp in length), showed clear separation between the isolates and species of the V. harveyi group. Amplified fragment length polymorphism (AFLP) analysis, performed previously, revealed that a representative isolate of this group, LMG 20370, was clearly separate from known Vibrio species (it belonged to the so-called AFLP cluster A31). DNA-DNA hybridization (DDH) experiments with representative isolates and type strains of the V. harveyi species group revealed high DDH between the novel isolates (more than 74?%) and less than 70?% DDH towards type strains of related Vibrio species, proving the novel species status of the isolates. Phenotypically, the novel species belongs to the arginine dihydrolase (A)-negative, lysine decarboxylase (L)-positive and ornithine decarboxylase (O)-positive (A-/L+/O+) cluster reported previously. Most species of the V. harveyi group (i.e. Vibrio rotiferianus, V. harveyi, V. parahaemolyticus and V. alginolyticus) also belong to this A-/L+/O+ cluster. However, several phenotypic features can be used for the identification of the novel species. In contrast to its closest phylogenetic neighbours, the novel species exhibits esterase (C4) and N-acetyl-?-glucosaminidase activities, but it does not produce acetoin, does not use citrate, ?-ketoglutaric acid or propionic acid and does not ferment melibiose. The novel species can also be differentiated on the basis of the presence of the fatty acids C(17?:?0,) C(17?:?1)?8c, iso-C(17?:?0) and iso-C(13?:?0) and the absence of the fatty acid C(18?:?0). The name Vibrio communis sp. nov. is proposed for this taxon. Strain R-40496(T) (=LMG 25430(T) =CAIM 1816(T)) is the type strain. PMID:20305064

Chimetto, Luciane A; Cleenwerck, Ilse; Alves, Nelson; Silva, Bruno Sergio; Brocchi, Marcelo; Willems, Anne; De Vos, Paul; Thompson, Fabiano L

2011-02-01

127

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

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

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

2012-01-01

128

Radiofrequency transmission line for bioluminescent Vibrio sp. irradiation  

NASA Astrophysics Data System (ADS)

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).

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

2012-07-01

129

The fusion Vibrio campbellii luciferase as a eukaryotic gene reporter.  

PubMed

Bacterial luciferase from Vibrio campbellii is a thermostable enzyme with an in vitro thermal inactivation half-life of ~1020 min at 37°C. The enzyme also binds tightly to reduced FMN. In this study, a V. campbellii fusion luciferase construct in which the ? and ? subunits are linked with a decapeptide was made and characterized. In general, the overall enzymatic properties of the two enzymes are similar. Expression of the enzymes in Escherichia coli demonstrated that the V. campbellii fusion luciferase emits less light than the native luciferase, but still emits a much greater amount of light than native luciferase from Vibrio harveyi and Photobacterium leiognathi TH1. The intensity of light emitted by the V. campbellii fusion luciferase was more than 80-fold greater than that from the V. harveyi native luciferase when expressed at 37°C. Biochemical characterization has shown that the V. campbellii fusion luciferase also retains a high binding affinity for reduced flavin mononucleotide and high thermostability. The levels of bioluminescence emitted by the V. campbellii fusion luciferase expressed in HEK293T cells reached ~1×10(6) Relative Light Units/mg total protein. These findings suggest that the V. campbellii fusion luciferase is a promising candidate for further development as a luciferase-based reporter for eukaryotic systems. PMID:23000378

Tinikul, Ruchanok; Thotsaporn, Kittisak; Thaveekarn, Wichit; Jitrapakdee, Sarawut; Chaiyen, Pimchai

2012-12-31

130

AphA and LuxR/HapR reciprocally control quorum sensing in vibrios  

PubMed Central

Bacteria cycle between periods when they perform individual behaviors and periods when they perform group behaviors. These transitions are controlled by a cell–cell communication process called quorum sensing, in which extracellular signal molecules, called autoinducers (AIs), are released, accumulate, and are synchronously detected by a group of bacteria. AI detection results in community-wide changes in gene expression, enabling bacteria to collectively execute behaviors such as bioluminescence, biofilm formation, and virulence factor production. In this study, we show that the transcription factor AphA is a master regulator of quorum sensing that operates at low cell density (LCD) in Vibrio harveyi and Vibrio cholerae. In contrast, LuxR (V. harveyi)/HapR (V. cholerae) is the master regulator that operates at high cell density (HCD). At LCD, redundant small noncoding RNAs (sRNAs) activate production of AphA, and AphA and the sRNAs repress production of LuxR/HapR. Conversely, at HCD, LuxR/HapR represses aphA. This network architecture ensures maximal AphA production at LCD and maximal LuxR/HapR production at HCD. Microarray analyses reveal that 300 genes are regulated by AphA at LCD in V. harveyi, a subset of which is also controlled by LuxR. We propose that reciprocal gradients of AphA and LuxR/HapR establish the quorum-sensing LCD and HCD gene expression patterns, respectively. PMID:21325136

Rutherford, Steven T.; van Kessel, Julia C.; Shao, Yi; Bassler, Bonnie L.

2011-01-01

131

Vibrio and Pregnancy  

MedlinePLUS

... html Centers for Disease Control and Prevention.2013. Vibrio parahaemolyticus . [Accessed January 2015]. Available at URL: http://www.cdc.gov/vibrio/vibriop.html Centers for Disease Control and Prevention. ...

132

Visick Lab: Home of the Vibrio-Euprymna Symbiosis  

NSDL National Science Digital Library

This website features general information about the lab of Karen Visick, which studies the genes needed to establish an interaction between the small Hawaiian squid Euprymna scolopes and its luminescent symbiont, the marine bacterium Vibrio fischeri. It features links to more information about current research in the Visick lab, lab members and events, and the summer research program and microbiology department at Loyola University.

Visick, Karen; University, Loyola

133

Genome Sequences of Vibrio navarrensis, a Potential Human Pathogen  

PubMed Central

Vibrio navarrensis is an aquatic bacterium recently shown to be associated with human illness. We report the first genome sequences of three V. navarrensis strains obtained from clinical and environmental sources. Preliminary analyses of the sequences reveal that V. navarrensis contains genes commonly associated with virulence in other human pathogens. PMID:25414502

Gladney, Lori M.; Katz, Lee S.; Knipe, Kristen M.; Rowe, Lori A.; Conley, Andrew B.; Rishishwar, Lavanya; Mariño-Ramírez, Leonardo

2014-01-01

134

2009 Macmillan Publishers Limited. All rights reserved. Sugar synthesis in a protocellular model leads  

E-print Network

leads to a cell signalling response in bacteria Paul M. Gardner1 , Klaus Winzer2 and Benjamin G. Davis1 mechanism of the marine bacterium Vibrio harveyi and stimulating a proportional bioluminescent response

Davis, Ben G.

135

Lessons from cholera & Vibrio cholerae.  

PubMed

Cholera is an acute form of diarrhoeal disease that plagued human civilization over the centuries. The sudden and explosive onset of the disease in the form of an outbreak or epidemic, coupled with high mortality and morbidity rates, had a tragic impact on the personal as well as social life of people living in the affected areas. The enormity of human sufferings led clinicians and scientists to carry out extensive research on cholera and Vibrio cholerae (the causative bacterium of the disease) leading to major discoveries that opened up novel areas of research or new disciplines in biomedical sciences. An attempt is made here to summarize some of these breakthroughs and outline their significance in broader perspectives. Finally, the possible impact of the global socio-political scenario on the spread of cholera epidemics (pandemicity of cholera) is briefly discussed. PMID:21415490

Ghose, Asoke C

2011-02-01

136

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

ERIC Educational Resources Information Center

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…

Hrizo, Stacy L.; Kaufmann, Nancy

2009-01-01

137

Vibrio fischeri lux Genes Play an Important Role in Colonization and Development of the Host Light Organ  

Microsoft Academic Search

The bioluminescent bacterium Vibrio fischeri and juveniles of the squid Euprymna scolopes specifically recognize and respond to one another during the formation of a persistent colonization within the host's nascent light-emitting organ. The resulting fully developed light organ contains brightly luminescing bacteria and has undergone a bacterium-induced program of tissue differentiation, one component of which is a swelling of the

KAREN L. VISICK; JAMIE FOSTER; JUDITH DOINO; MARGARET MCFALL-NGAI; EDWARD G. RUBY

2000-01-01

138

Vibrio fischeri metabolism: symbiosis and beyond.  

PubMed

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

Dunn, Anne K

2012-01-01

139

Chironomid Egg Masses as a Natural Reservoir of Vibrio cholerae Non-O1 and Non-O139 in Freshwater Habitats  

E-print Network

Chironomid Egg Masses as a Natural Reservoir of Vibrio cholerae Non-O1 and Non-O139 in Freshwater Received: 3 March 2003 / Accepted: 19 June 2003 / Online publication: 23 December 2003 Abstract Cholera is a diarrheal disease caused by the gram-nega- tive bacterium Vibrio cholerae, and an estimated 120,000 deaths

Halpern, Malka

140

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

E-print Network

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

141

Quorum Sensing Regulatory Cascades Control Vibrio fluvialis Pathogenesis  

PubMed Central

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

Wang, Yunduan; Wang, Hui; Liang, Weili; Hay, Amanda J.; Zhong, Zengtao

2013-01-01

142

Complete Genome Sequence of Vibrio alginolyticus ATCC 17749T  

PubMed Central

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

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

2015-01-01

143

Detection of V. harveyi in shrimp postlarvae and hatchery tank water by the Most Probable Number technique with PCR  

Microsoft Academic Search

V. harveyi is the cause of serious disease in the shrimp industry in Thailand during cultivation. In this study, the gyrB gene of V. harveyi NICA, isolated from shrimp in Thailand, was sequenced. A pair of specific primers (A2B3) was designed that allowed amplification of a 363 bp gene fragment of V. harveyi. No cross reaction was detected in 17 other

Sawitree Thaithongnum; Pimonsri Ratanama; Karnchana Weeradechapol; Ampaitip Sukhoom; Varaporn Vuddhakul

2006-01-01

144

Cultivation of Vibrio foetus  

Microsoft Academic Search

Vibrio foetus is non-pathogenic for small laboratory animals. As it can cause abortion in sheep and cattle, and is then found in the embryo, cultivation in incubated chicken eggs was attempted. The organism grows easily in the allantoic fluid of seven-to-nine-day eggs. Three days after inoculation, there is a rich growth of Vibrio foetus in the allantoic fluid. The organism

Jac. Jansen; H. Kunst

1951-01-01

145

Genes Similar to the Vibrio parahaemolyticus Virulence-Related Genes tdh, tlh, and vscC2 Occur in Other Vibrionaceae Species Isolated from a Pristine Estuary  

PubMed Central

Detection of the human pathogen Vibrio parahaemolyticus often relies on molecular biological analysis of species-specific virulence factor genes. These genes have been employed in determinations of V. parahaemolyticus population numbers and the prevalence of pathogenic V. parahaemolyticus strains. Strains of the Vibrionaceae species Photobacterium damselae, Vibrio diabolicus, Vibrio harveyi, and Vibrio natriegens, as well as strains similar to Vibrio tubiashii, were isolated from a pristine salt marsh estuary. These strains were examined for the V. parahaemolyticus hemolysin genes tdh, trh, and tlh and for the V. parahaemolyticus type III secretion system 2? gene vscC2 using established PCR primers and protocols. Virulence-related genes occurred at high frequencies in non-V. parahaemolyticus Vibrionaceae species. V. diabolicus was of particular interest, as several strains were recovered, and the large majority (>83%) contained virulence-related genes. It is clear that detection of these genes does not ensure correct identification of virulent V. parahaemolyticus. Further, the occurrence of V. parahaemolyticus-like virulence factors in other vibrios potentially complicates tracking of outbreaks of V. parahaemolyticus infections. PMID:24212573

Klein, Savannah L.; Gutierrez West, Casandra K.; Mejia, Diana M.

2014-01-01

146

Evidence that Water TransmitsVibrio vulnificus Biotype 2 Infections to Eels  

Microsoft Academic Search

Vibrio vulnificus biotype 2 is classically considered an obligate eel pathogen. However, it has recently been associated with one human septicemic case. In this paper, the opportunistic behavior of this pathogen is discussed. The bacterium can survive alone in brackish water or attached to eel surfaces for at least 14 days. It is able to spread through water and infect

CARMEN AMARO; ELENA G. BIOSCA; BELEN FOUZ; ELENA ALCAIDE; ANDCONSUELO ESTEVE

147

Roles of Bacterial Regulators in the Symbiosis between Vibrio fischeri and Euprymna scolopes  

E-print Network

and a niche safe from competing bacteria, V. fischeri provides the bioluminescence used by E. scolopes the bioluminescent marine bacterium Vibrio fischeri and the Hawaiian squid Euprymna scolopes provides a model system organ association (Boettcher and Ruby 1990). Furthermore, inoculation in the laboratory with bacteria

McFall-Ngai, Margaret

148

Randomly Amplified Polymorphic DNA Analysis of Starved and Viable but Nonculturable Vibrio vulnificus Cells  

Microsoft Academic Search

Vibrio vulnificus is an estuarine bacterium capable of causing a rapidly fatal infection in humans. Because of the low nutrient levels and temperature fluctuations found in the organism's natural habitat, the starvation state and viable but nonculturable (VBNC) state are of particular interest. A randomly amplified polymorphic DNA (RAPD) PCR protocol was developed previously for the detection of V. vulnificus

JENNIFER M. WARNER; JAMES D. OLIVER

1998-01-01

149

Molecular Characterization of Direct Target Genes and cis-Acting Consensus Recognized by Quorum-Sensing Regulator AphA in Vibrio parahaemolyticus  

PubMed Central

Background AphA is the master quorum-sensing (QS) regulator operating at low cell density in vibrios. Molecular regulation of target genes by AphA has been characterized in Vibrio harveyi and V. cholerae, but it is still poorly understood in V. parahaemolyticus. Methodology/Principal Findings The AphA proteins are extremely conserved in V. parahaemolyticus, Vibrio sp. Ex25, Vibrio sp. EJY3, V. harveyi, V. vulnificus, V. splendidus, V. anguillarum, V. cholerae, and V. furnissii. The above nine AphA orthologs appear to recognize conserved cis-acting DNA signals which can be represented by two consensus constructs, a 20 bp box sequence and a position frequency matrix. V. parahaemolyticus AphA represses the transcription of ahpA, qrr4, and opaR through direct AphA-target promoter DNA association, while it inhibits the qrr2-3 transcription in an indirect manner. Translation and transcription starts, core promoter elements for sigma factor recognition, Shine-Dalgarno sequences for ribosome recognition, and AphA-binding sites (containing corresponding AphA box-like sequences) were determined for the three direct AphA targets ahpA, qrr4, and opaR in V. parahaemolyticus. Conclusions/Significance AphA-mediated repression of ahpA, qrr2-4, and opaR was characterized in V. parahaemolyticus by using multiple biochemical and molecular experiments. The computational promoter analysis indicated the conserved mechanism of transcriptional regulation of QS regulator-encoding genes ahpA, qrr4, and opaR in vibrios. PMID:22984476

Sun, Fengjun; Zhang, Yiquan; Wang, Li; Yan, Xiaojuan; Tan, Yafang; Guo, Zhaobiao; Qiu, Jingfu; Yang, Ruifu; Xia, Peiyuan; Zhou, Dongsheng

2012-01-01

150

Active regulation of receptor ratios controls integration of quorum-sensing signals  

E-print Network

Active regulation of receptor ratios controls integration of quorum-sensing signals in Vibrio 8616; E-mail: wingreen@princeton.edu Received 20.1.11; accepted 19.4.11 Quorum sensing is a chemical exist in the quorum-sensing circuit of the model bacterium Vibrio harveyi. Using fluorescence microscopy

Mehta, Pankaj

151

Temperature regulation of virulence factors in the pathogen Vibrio coralliilyticus.  

PubMed

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

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

152

Pulmonary damage by Vibrio vulnificus cytolysin.  

PubMed Central

Vibrio vulnificus is an estuarine bacterium that causes septicemia and serious wound infection. Cytolysin produced by V. vulnificus has been incriminated as one of the important virulence determinants of bacterial infection. Cytolysin (8 hemolytic units) given intravenously to mice via their tail veins caused severe hemoconcentration and lethality. Cytolysin treatment greatly increased pulmonary wet weight and vascular permeability as measured by (125)I-labeled albumin leakage without affecting those factors of other organs significantly. Blood neutrophils were markedly decreased in number after cytolysin injection, with a concomitant increase in the level of pulmonary myeloperoxidase activity, indicating that cytolysin-induced neutropenia might be due to pulmonary sequestration of neutrophils. By microscopic examination, severe perivascular edema and neutrophil infiltration were evident in lung tissues. These results suggest that increased vascular permeability and neutrophil sequestration in the lungs are important factors in lethal activity by cytolysin. PMID:8698528

Park, J W; Ma, S N; Song, E S; Song, C H; Chae, M R; Park, B H; Rho, R W; Park, S D; Kim, H R

1996-01-01

153

Biodiversity of Vibrios  

PubMed Central

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

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

2004-01-01

154

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

PubMed

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

Kimbrough, John H; Stabb, Eric V

2013-11-01

155

Transcriptional Regulation of opaR, qrr2–4 and aphA by the Master Quorum-Sensing Regulator OpaR in Vibrio parahaemolyticus  

PubMed Central

Background Vibrio parahaemolyticus is a leading cause of infectious diarrhea and enterogastritis via the fecal-oral route. V. harveyi is a pathogen of fishes and invertebrates, and has been used as a model for quorum sensing (QS) studies. LuxR is the master QS regulator (MQSR) of V. harveyi, and LuxR-dependent expression of its own gene, qrr2–4 and aphA have been established in V. harveyi. Molecular regulation of target genes by the V. parahaemolyticus MQSR OpaR is still poorly understood. Methodology/Principal Findings The bioinformatics analysis indicated that V. parahaemolyticus OpaR, V. harveyi LuxR, V. vulnificu SmcR, and V. alginolyticus ValR were extremely conserved, and that these four MQSRs appeared to recognize the same conserved cis-acting signals, which was represented by the consensus constructs manifesting as a position frequency matrix and as a 20 bp box, within their target promoters. The MQSR box-like sequences were found within the upstream DNA regions of opaR, qrr2–4 and aphA in V. parahaemolyticus, and the direct transcriptional regulation of these target genes by OpaR were further confirmed by multiple biochemical experiments including primer extension assay, gel mobility shift assay, and DNase I footprinting analysis. Translation and transcription starts, core promoter elements for sigma factor recognition, Shine-Dalgarno sequences for ribosome recognition, and OpaR-binding sites were determined for the five target genes of OpaR, which gave a structural map of the OpaR-dependent promoters. Further computational promoter analysis indicated the above regulatory circuits were shared by several other closely related Vibrios but with slight exceptions. Conclusions/Significance This study gave a comprehensive computational and characterization of the direct transcriptional regulation of five target genes, opaR, qrr2–4 and ahpA, by OpaR in V. parahaemolyticus. These characterized regulatory circuits were conserved in V. harveyi and V. parahaemolyticus. PMID:22506036

Tan, Yafang; Guo, Zhaobiao; Yang, Ruifu; Zhou, Dongsheng

2012-01-01

156

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...

157

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

PubMed Central

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

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

2009-01-01

158

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

PubMed

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

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

2015-01-01

159

Genetic Determinants of Virulence in the Marine Fish Pathogen Vibrio anguillarum  

PubMed Central

One of the most studied fish pathogens is Vibrio anguillarum. Development of the genetics and biochemistry of the mechanisms of virulence in this fish pathogen together with clinical and ecologic studies has permitted the intensive development of microbiology in fish diseases. It is the intention of this review to compile the exhaustive knowledge accumulated on this bacterium and its interaction with the host fish by reporting a complete analysis of the V. anguillarum virulence factors and the genetics of their complexity. PMID:21625345

Naka, Hiroaki; Crosa, Jorge H.

2011-01-01

160

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

PubMed

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

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

2015-01-01

161

Retention of Vibrio parahaemolyticus in oyster tissues after chlorine dioxide treatment  

Microsoft Academic Search

Vibrio parahaemolyticus is an important food-borne bacterium that is closely related to food poisoning from consumption of raw or lightly-cooked oysters. Therefore, intensive efforts must be taken to depurate the contaminated oysters. Chlorine dioxide (ClO2) is considered to be a safe and effective disinfectant and is routinely applied for treatment of drinking water and seafood. However, the retention of V.

Dapeng Wang; Dandan Zhang; Wanyi Chen; Shuijing Yu; Xianming Shi

2010-01-01

162

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

PubMed Central

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

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

2015-01-01

163

Autecology of Vibrio vulnificus and Vibrio parahaemolyticus in tropical waters  

SciTech Connect

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.

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

1988-12-31

164

Role for cheR of Vibrio fischeri in the Vibrio-Squid Symbiosis  

PubMed Central

Upon hatching, the Hawaiian squid Euprymna scolopes is rapidly colonized by its symbiotic partner, the bioluminescent marine bacterium Vibrio fischeri. V. fischeri cells present in the seawater enter the light organ of juvenile squid in a process that requires bacterial motility. In this study, we investigated the role chemotaxis may play in establishing this symbiotic colonization. Previously we reported that V. fischeri migrates toward numerous attractants, including N-acetylneuraminic acid (NANA), a component of squid mucus. However, whether or not migration toward an attractant such as squid-derived NANA helps the bacterium to localize toward the light organ is unknown. When tested for the ability to colonize juvenile squid, a V. fischeri chemotaxis mutant defective for the methyltransferase CheR was outcompeted by the wild-type strain in co-inoculation experiments, even when the mutant was present in 4-fold excess. Our results suggest that the ability to perform chemotaxis is an advantage during colonization, but not essential. PMID:22182211

DeLoney-Marino, Cindy R.; Visick, Karen L.

2011-01-01

165

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

PubMed

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 in vitro 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

Tercero-Alburo, J J; González-Márquez, H; Bonilla-González, E; Quiñones-Ramírez, E I; Vázquez-Salinas, C

2014-11-01

166

Vibrio campbellii hmgA-mediated pyomelanization impairs quorum sensing, virulence, and cellular fitness.  

PubMed

Melanization due to the inactivation of the homogentisate-1,2-dioxygenase gene (hmgA) has been demonstrated to increase stress resistance, persistence, and virulence in some bacterial species but such pigmented mutants have not been observed in pathogenic members of the Vibrio Harveyi clade. In this study, we used Vibrio campbellii ATCC BAA-1116 as model organism to understand how melanization affected cellular phenotype, metabolism, and virulence. An in-frame deletion of the hmgA gene resulted in the overproduction of a pigment in cell culture supernatants and cellular membranes that was identified as pyomelanin. Unlike previous demonstrations in Vibrio cholerae, Burkholderia cepacia, and Pseudomonas aeruginosa, the pigmented V. campbellii mutant did not show increased UV resistance and was found to be ~2.7 times less virulent than the wild type strain in Penaeus monodon shrimp virulence assays. However, the extracted pyomelanin pigment did confer a higher resistance to oxidative stress when incubated with wild type cells. Microarray-based transcriptomic analyses revealed that the hmgA gene deletion and subsequent pyomelanin production negatively effected the expression of 129 genes primarily involved in energy production, amino acid, and lipid metabolism, and protein translation and turnover. This transcriptional response was mediated in part by an impairment of the quorum sensing regulon as transcripts of the quorum sensing high cell density master regulator LuxR and other operonic members of this regulon were significantly less abundant in the hmgA mutant. Taken together, the results suggest that the pyomelanization of V. campbellii sufficiently impairs the metabolic activities of this organism and renders it less fit and virulent than its isogenic wild type strain. PMID:24376440

Wang, Zheng; Lin, Baochuan; Mostaghim, Anahita; Rubin, Robert A; Glaser, Evan R; Mittraparp-Arthorn, Pimonsri; Thompson, Janelle R; Vuddhakul, Varaporn; Vora, Gary J

2013-01-01

167

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...

168

Surface-attachment sequence in Vibrio Cholerae  

NASA Astrophysics Data System (ADS)

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

Utada, Andrew; Gibiansky, Maxsim; Wong, Gerard

2013-03-01

169

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...

170

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

PubMed

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 30min 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?gL(-1))?linuron (EC50=30.5?gL(-1))>monolinuron (EC50=300?gL(-1)) for the duckweed and linuron (EC50=8.2mgL(-1))>diuron (EC50=9.2mg L(-1))>monolinuron (EC50=11.2mgL(-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

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

2015-01-01

171

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

PubMed Central

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.

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

2014-01-01

172

Ethanolamine utilization in Vibrio alginolyticus  

PubMed Central

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

2012-01-01

173

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

PubMed

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

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

2013-10-01

174

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

PubMed Central

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

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

2014-01-01

175

Genomics of Pathogenic Vibrio Species  

NASA Astrophysics Data System (ADS)

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.

Dziejman, Michelle; Yildiz, Fitnat H.

176

342 NATURE CHEMISTRY | VOL 1 | AUGUST 2009 | www.nature.com/naturechemistry news & views  

E-print Network

stimulate a bioluminescent response from a living bacterial cell. The well-known formose reaction involves sensing mechanisms of the marine bacterium Vibrio harveyi, giving rise to a proportional bioluminescent sensing, the means by which many bacteria communicate by release and detection of small-molecule `mes

Davis, Ben G.

177

Identification of a conserved bacterial protein secretion system in Vibrio cholerae using the Dictyostelium host model system  

Microsoft Academic Search

The bacterium Vibrio cholerae, like other human pathogens that reside in environmental reservoirs, survives predation by unicellular eukaryotes. Strains of the O1 and O139 serogroups cause cholera, whereas non-O1\\/non-O139 strains cause human infections through poorly defined mechanisms. Using Dictyostelium discoideum as a model host, we have identified a virulence mechanism in a non-O1\\/non-O139 V. cholerae strain that involves extracellular translocation

Stefan Pukatzki; Amy T. Ma; Derek Sturtevant; Bryan Krastins; David Sarracino; William C. Nelson; John F. Heidelberg; John J. Mekalanos

2006-01-01

178

Bacteremia caused by Vibrio hollisae.  

PubMed Central

Vibrio hollisae was recovered from the bloodstream of a 36-year-old man with chronic active hepatitis who was admitted to the hospital with signs of gastrointestinal illness. V. hollisae is an infrequent human pathogen associated with seafood ingestion. No etiologic link to seafood was demonstrated in this case report. PMID:3343331

Rank, E L; Smith, I B; Langer, M

1988-01-01

179

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...

180

Vibrio metoecus sp. nov., a close relative of Vibrio cholerae isolated from coastal brackish ponds and clinical specimens.  

PubMed

A Gram-staining-negative, curved-rod-shaped bacterium with close resemblance to Vibrio cholerae, the aetiological agent of cholera, was isolated over the course of several years from coastal brackish water (17 strains) and from clinical cases (two strains) in the United States. 16S rRNA gene identity with V. cholerae exceeded 98?% yet an average nucleotide identity based on genome data of around 86?% and multi locus sequence analysis of six housekeeping genes (mdh, adk, gyrB, recA, pgi and rpoB) clearly delineated these isolates as a distinct genotypic cluster within the V. cholerae-V. mimicus clade. Most standard identification techniques do not differentiate this cluster of isolates from V. cholerae. Only amplification of the ompW gene using V. cholerae-specific primers and a negative Voges-Proskauer test showed a difference between the two clusters. Additionally, all isolated strains differed phenotypically from V. cholerae in their ability to utilize N-acetyl-d-galactosamine and d-glucuronic acid as sole carbon sources. Furthermore, they were generally unable to infect the slime mould Dictyostelium discoideum, a widespread ability in V. cholerae. Based on these clear phenotypic differences that are not necessarily apparent in standard tests as well as average nucleotide identity and phylogeny of protein-coding genes, we propose the existence of a novel species, Vibrio metoecus sp. nov. with the type strain OP3H(T) (?=?LMG 27764(T)?=?CIP 110643(T)). Due to its close resemblance to V. cholerae and the increasing number of strains isolated over the past several years, we suggest that V. metoecus sp. nov. is a relatively common species of the genus Vibrio, isolates of which have been identified as atypical isolates of V. cholerae in the past. Its isolation from clinical samples also indicates that strains of this species, like V. cholerae, are opportunistic pathogens. PMID:24972615

Kirchberger, Paul C; Turnsek, Maryann; Hunt, Dana E; Haley, Bradd J; Colwell, Rita R; Polz, Martin F; Tarr, Cheryl L; Boucher, Yan

2014-09-01

181

Squid-Derived Chitin Oligosaccharides Are a Chemotactic Signal during Colonization by Vibrio fischeri  

PubMed Central

Chitin, a polymer of N-acetylglucosamine (GlcNAc), is noted as the second most abundant biopolymer in nature. Chitin serves many functions for marine bacteria in the family Vibrionaceae (“vibrios”), in some instances providing a physical attachment site, inducing natural genetic competence, and serving as an attractant for chemotaxis. The marine luminous bacterium Vibrio fischeri is the specific symbiont in the light-emitting organ of the Hawaiian bobtail squid, Euprymna scolopes. The bacterium provides the squid with luminescence that the animal uses in an antipredatory defense, while the squid supports the symbiont's nutritional requirements. V. fischeri cells are harvested from seawater during each host generation, and V. fischeri is the only species that can complete this process in nature. Furthermore, chitin is located in squid hemocytes and plays a nutritional role in the symbiosis. We demonstrate here that chitin oligosaccharides produced by the squid host serve as a chemotactic signal for colonizing bacteria. V. fischeri uses the gradient of host chitin to enter the squid light organ duct and colonize the animal. We provide evidence that chitin serves a novel function in an animal-bacterial mutualism, as an animal-produced bacterium-attracting synomone. PMID:22522684

Schaefer, Amy L.; Brennan, Caitlin A.; Heath-Heckman, Elizabeth A. C.; DeLoney-Marino, Cindy R.; McFall-Ngai, Margaret J.

2012-01-01

182

Complete Genome Sequence of Vibrio parahaemolyticus Bacteriophage vB_VpaM_MAR  

PubMed Central

Vibrio parahaemolyticus is a major pathogen that is mainly associated with seafood and is a global food safety issue. Our objective was to isolate and completely sequence a specific phage against this bacterium. Phage vB_VpaM_MAR is able to lyse 76% of the V. parahaemolyticus strains tested. MAR belongs to the Myoviridae family and has a genome comprised of double-stranded DNA with a size of 41,351 bp, a G+C content of 51.3%, and 62 open reading frames (ORFs). Bioinformatic analysis showed that phage MAR is closely related to Vibrio phages VHML, VP58.5, and VP882 and Halomonas aquamarina phage ?HAP-1. PMID:23118463

Alanis Villa, Argentina; Kropinski, Andrew M.; Abbasifar, Reza

2012-01-01

183

Vibrio caribbeanicus sp. nov., isolated from the marine sponge Scleritoderma cyanea.  

PubMed

A Gram-negative, oxidase-positive, catalase-negative, facultatively anaerobic, motile, curved rod-shaped bacterium, strain N384(T), was isolated from a marine sponge (Scleritoderma cyanea; phylum Porifera) collected from a depth of 795 feet (242 m) off the west coast of Curaçao. On the basis of 16S rRNA gene sequencing, strain N384(T) was shown to belong to the genus Vibrio, most closely related to Vibrio brasiliensis LMG 20546(T) (98.8% similarity), Vibrio nigripulchritudo ATCC 27043(T) (98.5%), Vibrio tubiashii ATCC 19109(T) (98.6%) and V. sinaloensis DSM 21326(T) (98.2%). The DNA G+C content of strain N384(T) was 41.6 mol%. An analysis of concatenated sequences of five genes (gyrB, rpoA, pyrH, mreB and ftsZ; 4068 bp) demonstrated a clear separation between strain N384(T) and its closest neighbours and clustered strain N384(T) into the 'Orientalis' clade of vibrios. Phenotypically, the novel species belonged to the arginine dihydrolase-positive, lysine decarboxylase- and ornithine decarboxylase-negative (A+/L-/O-) cluster. The novel species was also differentiated on the basis of fatty acid composition, specifically that the proportions of iso-C(13:0), iso-C(15:0), C(15:0), iso-C(16:0), C(16:0), iso-C(17:0), C(17:1)?8c and C(17:0) were significantly different from those found in V. brasiliensis and V. sinaloensis. The results of DNA-DNA hybridization, average nucleotide identity and physiological and biochemical tests further allowed differentiation of this strain from other described species of the genus Vibrio. Collectively, these findings confirm that strain N384(T) represents a novel Vibrio species, for which the name Vibrio caribbeanicus sp. nov. is proposed, with the type strain N384(T) (?=?ATCC BAA-2122(T)?=?DSM 23640(T)). PMID:21930677

Hoffmann, Maria; Monday, Steven R; Allard, Marc W; Strain, Errol A; Whittaker, Paul; Naum, Marianna; McCarthy, Peter J; Lopez, Jose V; Fischer, Markus; Brown, Eric W

2012-08-01

184

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

PubMed Central

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

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

2014-01-01

185

Ecology of Vibrio parahaemolyticus in Chesapeake Bay  

PubMed Central

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

Kaneko, Tatsuo; Colwell, Rita R.

1973-01-01

186

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

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

Balcázar, José Luis; Rojas-Luna, Tyrone; Cunningham, David P

2007-10-01

187

Ion selectivity of the Vibrio alginolyticus flagellar motor.  

PubMed Central

The marine bacterium, Vibrio alginolyticus, normally requires sodium for motility. We found that lithium will substitute for sodium. In neutral pH buffers, the membrane potential and swimming speed of glycolyzing bacteria reached maximal values as sodium or lithium concentration was increased. While the maximal potentials obtained in the two cations were comparable, the maximal swimming speed was substantially lower in lithium. Over a wide range of sodium concentration, the bacteria maintained an invariant sodium electrochemical potential as determined by membrane potential and intracellular sodium measurements. Over this range the increase of swimming speed took Michaelis-Menten form. Artificial energization of swimming motility required imposition of a voltage difference in concert with a sodium pulse. The cation selectivity and concentration dependence exhibited by the motile apparatus depended on the viscosity of the medium. In high-viscosity media, swimming speeds were relatively independent of either ion type or concentration. These facts parallel and extend observations of the swimming behavior of bacteria propelled by proton-powered flagella. In particular, they show that ion transfers limit unloaded motor speed in this bacterium and imply that the coupling between ion transfers and force generation must be fairly tight. PMID:2394685

Liu, J Z; Dapice, M; Khan, S

1990-01-01

188

Phage therapy treatment of the coral pathogen Vibrio coralliilyticus  

PubMed Central

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

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

2013-01-01

189

Properties of proteolytic toxin of Vibrio anguilolarum from diseased flounder  

NASA Astrophysics Data System (ADS)

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 25°C. The protease present in ECP showed maximal activity at pH 8 and 55°C; was completely inactivated by application of 80°C 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 50°C decreased the lethal toxicity of ECP. When heated at 100°C, 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.

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

2002-12-01

190

Multiplex Real-time Polymerase Chain Reaction Assays for Simultaneous Detection of Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus  

PubMed Central

Objectives A multiplex real-time polymerase chain reaction (RT-PCR) method was developed for the identification of three Vibrio species: Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus. Methods Specific primers and probes targeting the hlyA, tlh, and vvhA genes were selected and used for multiplex real-time PCR to confirm the identification of V. cholerae, V. parahaemolyticus, and V. vulnificus, respectively. This method was applied to screen Vibrio species from environmental samples and combining it with a culture-based method, its effectiveness was evaluated in comparison with culture-based methods alone. Results Specific PCR fragments were obtained from isolates belonging to the target species, indicating a high specificity of this multiplex real-time PCR. No cross-reactivity with the assay was observed between the tested bacteria. The sensitivity of the multiplex real-time PCR was found to have a lower limit of 104 colony-forming units/reaction for all three Vibrio species. The combination strategy raised the isolation ratio of all three Vibrio species 1.26- to 2.75-fold. Conclusion This assay provides a rapid, sensitive, and specific technique to detect these three Vibrio species in the environment. PMID:24159544

Park, Jie Yeun; Jeon, Semi; Kim, Jun Young; Park, Misun; Kim, Seonghan

2013-01-01

191

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

PubMed

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

de Souza Santos, Marcela; Orth, Kim

2015-02-01

192

Essential Role for Estrogen in Protection against Vibrio vulnificus-Induced Endotoxic Shock  

PubMed Central

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

Merkel, Sandra M.; Alexander, Sarah; Zufall, Eric; Oliver, James D.; Huet-Hudson, Yvette M.

2001-01-01

193

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

NASA Astrophysics Data System (ADS)

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.

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

2014-09-01

194

Selection and identification of a DNA aptamer targeted to Vibrio parahemolyticus.  

PubMed

A whole-bacterium systemic evolution of ligands by exponential enrichment (SELEX) method was applied to a combinatorial library of FAM-labeled single-stranded DNA molecules to identify DNA aptamers demonstrating specific binding to Vibrio parahemolyticus . FAM-labeled aptamer sequences with high binding affinity to V. parahemolyticus were identified by flow cytometric analysis. Aptamer A3P, which showed a particularly high binding affinity in preliminary studies, was chosen for further characterization. This aptamer displayed a dissociation constant (K(d)) of 16.88 ± 1.92 nM. Binding assays to assess the specificity of aptamer A3P showed a high binding affinity (76%) for V. parahemolyticus and a low apparent binding affinity (4%) for other bacteria. Whole-bacterium SELEX is a promising technique for the design of aptamer-based molecular probes for microbial pathogens that does not require the labor-intensive steps of isolating and purifying complex markers or targets. PMID:22480209

Duan, Nuo; Wu, Shijia; Chen, Xiujuan; Huang, Yukun; Wang, Zhouping

2012-04-25

195

The Vibrio cholerae Genome Database  

NSDL National Science Digital Library

The Institute For Genomic Research (TIGR) has placed online the latest versions of the DNA sequence of both chromosomes of the cholera pathogen Vibrio cholerae. The TIGR site offers data access via a hypertext Gene Identification Table, DNA Molecule Information, Gene Name Search, Locus Search, RNA Gene Table, Paralogous Gene Families, a Sequence Search, or by download (FTP). Originally published by Heidelberg et al. in the journal Nature [106:477-483, 2000], further information is available to users via links at the TIGR site.

196

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

PubMed Central

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

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

2013-01-01

197

Two cases of bacteriemia caused by nontoxigenic, non-O1, non-O139 Vibrio cholerae isolates in Ho Chi Minh City, Vietnam.  

PubMed

The toxigenic bacterium Vibrio cholerae belonging to the O1 and O139 serogroups is commonly associated with epidemic diarrhea in tropical settings; other diseases caused by this environmental pathogen are seldom identified. Here we report two unassociated cases of nonfatal, nontoxigenic V. cholerae non-O1, non-O139 bacteremia in patients with comorbidities in Ho Chi Minh City, Vietnam, that occurred within a 4-week period. PMID:25122858

Lan, Nguyen Phu Huong; Nga, Tran Vu Thieu; Yen, Nguyen Thi Thu; Dung, Le Thi; Tuyen, Ha Thanh; Campbell, James I; Whitehorn, Jamie; Thwaites, Guy; Chau, Nguyen Van Vinh; Baker, Stephen

2014-10-01

198

Two Cases of Bacteriemia Caused by Nontoxigenic, Non-O1, Non-O139 Vibrio cholerae Isolates in Ho Chi Minh City, Vietnam  

PubMed Central

The toxigenic bacterium Vibrio cholerae belonging to the O1 and O139 serogroups is commonly associated with epidemic diarrhea in tropical settings; other diseases caused by this environmental pathogen are seldom identified. Here we report two unassociated cases of nonfatal, nontoxigenic V. cholerae non-O1, non-O139 bacteremia in patients with comorbidities in Ho Chi Minh City, Vietnam, that occurred within a 4-week period. PMID:25122858

Lan, Nguyen Phu Huong; Nga, Tran Vu Thieu; Yen, Nguyen Thi Thu; Dung, Le Thi; Tuyen, Ha Thanh; Campbell, James I.; Whitehorn, Jamie; Thwaites, Guy; Chau, Nguyen Van Vinh

2014-01-01

199

Vibrio chromosome-specific families  

PubMed Central

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

Lukjancenko, Oksana; Ussery, David W.

2014-01-01

200

"Build a Bacterium" Scavenger Hunt  

NSDL National Science Digital Library

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

Hare, Janelle

2012-01-01

201

Vibrio variabilis sp. nov. and Vibrio maritimus sp. nov., isolated from Palythoa caribaeorum.  

PubMed

Two novel vibrio isolates (R-40492(T) and R-40493(T)) originating from the zoanthid Palythoa caribaeorum in Brazil in 2005 were taxonomically characterized by means of a polyphasic approach comprising multilocus sequence analysis (MLSA), DNA-DNA hybridization (DDH), ?T(m) analysis and phenotypic characterization. Phylogenetic analysis based on 16S rRNA gene sequences showed that R-40492(T) and R-40493(T) fell within the genus Vibrio and were most closely related to each other with 99% similarity; similarities of these two novel isolates towards Vibrio neptunius LMG 20536(T), Vibrio coralliilyticus LMG 20984(T), Vibrio nigripulchritudo LMG 3896(T), Vibrio sinaloensis LMG 25238(T) and Vibrio brasiliensis LMG 20546(T) varied between 97.1 and 98.5%. DDH experiments showed that the two isolates had less than 15% relatedness to the phylogenetically most closely related Vibrio species. R-40492(T) and R-40493(T) had 55-57% relatedness to each other. The ?T(m) between R-40492(T) and R-40493(T) was 6.12 °C. In addition, MLSA of concatenated sequences (16S rRNA, ftsZ, gyrB, recA, rpoA, topA, pyrH and mreB; 6035 bp in length) showed that the two novel isolates formed a separate branch with less than 92% concatenated gene sequence similarity towards known species of vibrios. Two novel species are proposed to accommodate these novel isolates, namely Vibrio variabilis sp. nov. (type strain, R-40492(T)=LMG 25438(T)=CAIM 1454(T)) and Vibrio maritimus sp. nov. (type strain, R-40493(T)=LMG 25439(T)=CAIM 1455(T)). PMID:21296931

Chimetto, Luciane A; Cleenwerck, Ilse; Moreira, Ana Paula B; Brocchi, Marcelo; Willems, Anne; De Vos, Paul; Thompson, Fabiano L

2011-12-01

202

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

PubMed

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

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

2012-10-01

203

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

PubMed Central

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

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

2012-01-01

204

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

PubMed

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

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

2014-10-01

205

Vibrio biofilms: so much the same yet so different  

PubMed Central

Vibrios are natural inhabitants of aquatic environments and form symbiotic or pathogenic relationships with eukaryotic hosts. Recent studies reveal that the ability of vibrios to form biofilms – i.e. matrix-enclosed, surface-associated communities– depends upon specific structural genes (flagella, pili, and exopolysaccharide biosynthesis) and regulatory processes (two-component regulators, quorum sensing, and c-di-GMP signaling). In this review, we compare and contrast mechanisms and regulation of biofilm formation by Vibrio species, with a focus on Vibrio cholerae, Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio fischeri. While many aspects are the same, others differ dramatically. Critical questions that remain to be answered regarding the molecular underpinnings of Vibrio biofilm formation will also be discussed. PMID:19231189

Yildiz, Fitnat H.; Visick, Karen L.

2009-01-01

206

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...

207

Specific, nonradioactive detection of the NHP bacterium in Penaeus vannamei by in situ hybridization.  

PubMed

Necrotizing hepatopancreatitis (NHP) is a disease of farm-raised Pacific white shrimp (Penaeus vannamei) caused by a pleomorphic intracellular bacterium. A DNA probe that is specific for the etiologic agent of necrotizing hepatopancreatitis was devised and tested in an in situ hybridization assay. A procedure was developed for labeling a single-stranded DNA probe with digoxigenin by the polymerase chain reaction. The DNA probe encompasses the V1 and V2 variable regions of the 16S ribosomal RNA (rRNA) gene and is designed to hybridize to complementary sequences of the 16S rRNA of the NHP bacterium. The probe was tested on fixed, paraffin-embedded specimens, and an intense, specific hybridization signal was localized to the cytoplasm of hepatopancreatic epithelial cells that were infected with the NHP bacterium, as demonstrated by serial sections stained with hematoxylin and eosin or the Steiner and Steiner method. Negative results were obtained from normal shrimp and from shrimp infected with Vibrio spp. The specificity of the probe was confirmed using either mammalian or avian tissues infected with other intracellular bacteria, including Ehrlichia canis, Salmonella enteritidis, Brucella abortus, and Chlymidia spp., and using another species of shrimp (P. monodon) infected with a different rickettisa-like intracellular bacterium. PMID:8844575

Loy, J K; Frelier, P F

1996-07-01

208

Comparison of the Heme Iron Utilization Systems of Pathogenic Vibrios  

Microsoft Academic Search

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. parah- aemolyticus 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

C. E. RASHIDI; M. Y. MORA; S. M. PAYNE; D. P. HENDERSON

1999-01-01

209

Expression, purification, and characterization of thermolabile hemolysin (TLH) from Vibrio alginolyticus.  

PubMed

Hemolysin is a putative pathogenicity factor in many bacterial pathogens. In this study, a DNA fragment containing the open reading frame (1254 bp) of the thermolabile hemolysin gene (tlh) from Vibrio alginolyticus V05 was amplified and cloned into the expression plasmid pET-24d(+). The deduced amino acid sequence of the thermolabile hemolysin (TLH) shared 94 and 83% identity with the lecithin-dependent hemolysin (LDH)/TLH of V. parahaemolyticus and V. harveyi thermolabile hemolysin (VHH), respectively. The sequence analysis also indicated that it contained a GDSL lipase domain like VHH. The recombinant protein with a predicted molecular mass of 47.2 kDa was expressed in the Escherichia coli strain BL21 (DE3) as a His-tag fused protein. TLH purified by the nickel-nitrilotriacetic acid (Ni-NTA) His-Bind Resin method showed phospholipase activity on an egg yolk emulsion plate and hemolytic activity against flounder erythrocytes with a specific activity of 18 hemolytic units microg(-1). The addition of divalent cations at different concentrations decreased hemolytic activity of the purified TLH, but monavalent cations did not affect hemolytic activity. The hemolytic activity of TLH was also markedly inhibited by protein modification reagents, i.e. beta-mercaptoethanol, phenylmethylsulfonyl fluoride, and 5,5'-dithio-bis(2-nitrobenzoic acid). Moreover, TLH was toxic to zebrafish when injected intraperitoneally, with a median lethal dose (LD50) of 0.8 microg protein g(-1) fish. This work shows that TLH could potentially be developed as a vaccine and used as a diagnostic tool for vibriosis. PMID:20662368

Jia, Airong; Woo, Norman Y S; Zhang, Xiao-Hua

2010-06-11

210

VCA1008: An Anion-Selective Porin of Vibrio Cholerae.  

PubMed

A putative porin function has been assigned to VCA1008 of Vibrio cholerae. Its coding gene, vca1008, is expressed upon colonization of the small intestine in infant mice and human volunteers, and is essential for infection. In vitro, vca1008 is expressed under inorganic phosphate limitation and, in this condition, VCA1008 is the major outer membrane protein of the bacterium. Here, we provide the first functional characterization of VCA1008 reconstituted into planar lipid bilayers. Our main findings were: 1) VCA1008 forms an ion channel that, at high voltage (~±100mV), presents a voltage-dependent activity and displays closures typical of trimeric porins, with a conductance of 4.28±0.04 nS (n=164) in 1M KCl; 2) It has a preferred selectivity for anions over cations; 3) Its conductance saturates with increasing inorganic phosphate concentration, suggesting VCA1008 contains binding site(s) for this anion; 4) Its ion selectivity is controlled by both fixed charged residues within the channel and diffusion along the pore; 5) Partitioning of poly (ethylene glycol)s (PEGs) of different molecular mass suggests that VCA1008 channel has a pore exclusion limit of 0.9nm. PMID:25462170

Goulart, Carolina L; Bisch, Paulo M; von Krüger, Wanda M A; Homblé, Fabrice

2015-02-01

211

Mechanisms of iron regulation of luminescence in Vibrio fischeri  

SciTech Connect

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

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

1985-04-01

212

Utilization of hemin and hemoglobin by Vibrio vulnificus biotype 2.  

PubMed Central

The eel pathogen Vibrio vulnificus biotype 2 is able to use hemoglobin (Hb) and hemin (Hm) to reverse iron limitation. In this stud, the adjuvant effect of both compounds on eel pathogenicity has been evaluated and confirmed. Further, we have studied the heme-iron acquisition mechanism displayed by this bacterium. Whole cells were capable of binding Hb and Hm, independently of (i) iron levels in growth medium and (ii) the presence of polysaccharide capsules on bacterial surface. The Hb- and Hm-binding capacity was retained by the outer membrane protein (OMP) fraction and was abolished after proteolytic digestion of OMP samples. Western blotting (immunoblotting) of denatured OMPs revealed that two major protein bands of 36 and 32 kDa were involved in both Hm and Hb binding. The expression of these proteins was not affected by iron levels. In addition, V. vulnificus biotype 2 produced extracellular proteases, not regulated by iron, that were active against native Hb. In conclusion, the overall data suggest that the eel pathogen V. vulnificus biotype 2 can obtain iron by means of a mechanism which involves a direct interaction between the heme moiety and constitutive OMPs. PMID:8702273

Fouz, B; Mazoy, R; Lemos, M L; del Olmo, M J; Amaro, C

1996-01-01

213

Control of luminous Vibrio species in penaeid aquaculture ponds  

Microsoft Academic Search

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

D. J. W Moriarty

1998-01-01

214

Proton circulation in Vibrio costicola.  

PubMed Central

The importance of proton movements was assessed in the moderate halophile Vibrio costicola. When anaerobic cells in acidic buffer (pH 6.5) were given an O2 pulse, protons were extruded regardless of the presence of Na+. At pH 8.5, however, V. costicola produced an acidic response to an O2 pulse in the absence of Na+ and an alkaline response when Na+ was present. An Na+/H+ antiport activity was confirmed at pH 8.5. All of these effects were prevented by protonophores or butanol treatment. Growth in complex medium at pH 8.5 was prevented by a high concentration (50 microM) of carbonyl cyanide m-chlorophenyl-hydrazone (CCCP) or a low concentration (5 microM) of another protonophore, 3,3',4',5-tetrachlorosalicylanilide (TCS). The relative ineffectiveness of the former protonophore was caused by the proteose peptone and tryptone ingredients of the complex medium, since 5 microM completely prevented growth in their absence. The results are explained by a primary respiratory-linked proton efflux coupled to a secondary Na+/H+ antiport operating at alkaline pH. Evidence was seen for a role of Na+ in stimulating proton influx at alkaline pH, presumably via the pH homeostasis mechanism. PMID:2981820

Hamaide, F; Kushner, D J; Sprott, G D

1985-01-01

215

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

PubMed Central

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 structure–activity 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

TAKEDA, Yoshifumi

2011-01-01

216

Plasmid carriage in Vibrio vulnificus and other lactose-fermenting marine vibrios.  

PubMed Central

A total of 42 clinical and environmental isolates of Vibrio vulnificus were examined for plasmid carriage. Of these, only five (12%) harbored plasmids, which were of various molecular weights. In contrast, 20 of 32 (62.5%) unidentified lactose-fermenting Vibrio spp. were found to possess plasmids with masses of 2.1 to 150 megadaltons. In these isolates, multiple plasmids were common, with an average of 2.25 plasmids per plasmid-containing strain. Attempts to demonstrate a correlation with the plasmids identified in the various Vibrio spp. and a variety of phenotypic traits, production of several enzymes potentially involved in virulence, cytotoxicity for Chinese hamster ovary cells, and mouse lethality were unsuccessful. A correlation was observed, however, between the presence of a 6.5-megadalton plasmid and resistance to pteridine 0/129. It was concluded that V. vulnificus, unlike most other Vibrio spp., shows a general lack of these extrachromosomal elements. PMID:3729404

Davidson, L S; Oliver, J D

1986-01-01

217

Antibacterial activity of the lipopetides produced by Bacillus amyloliquefaciens M1 against multidrug-resistant Vibrio spp. isolated from diseased marine animals.  

PubMed

In this work, the antibacterial activity of the lipopeptides produced by Bacillus amyloliquefaciens M1 was examined against multidrug-resistant Vibrio spp. and Shewanella aquimarina isolated from diseased marine animals. A new and cheap medium which contained 1.0 % soybean powder, 1.5 % wheat flour, pH 7.0 was developed. A crude surfactant concentration of 0.28 mg/ml was obtained after 18 h of 10-l fermentation and diameter of the clear zone on the plate seeded with Vibrio anguillarum was 34 mm. A preliminary characterization suggested that the lipopeptide N3 produced by B. amyloliquefaciens M1 was the main product and contained the surfactin isoforms with amino acids (GLLVDLL) and hydroxy fatty acids (of 12-15 carbons in length). The evaluation of the antibacterial activity of the lipopeptide N3 was carried out against S. aquimarina and nine species of Vibrio spp.. It was found that all the Vibrio spp. and S. aquimarina showed resistance to several different antibiotics, suggesting that they were the multidrug resistance. It was also indicated that all the Vibrio spp. strains and S. aquimarina were sensitive to the surfactin N3, in particular V. anguillarum. The results demonstrated that the lipopeptides produced by B. amyloliquefaciens M1 had a broad spectrum of action, including antibacterial activity against the pathogenic Vibrio spp. with multidrug-resistant profiles. After the treatment with the lipopeptide N3, the cell membrane of V. anguillarum was damaged, and the whole cells of the bacterium were disrupted. PMID:24132666

Xu, Hong-Mei; Rong, Yan-Jun; Zhao, Ming-Xin; Song, Bo; Chi, Zhen-Ming

2014-01-01

218

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

Microsoft Academic Search

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

Sumio Shinoda

219

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

PubMed Central

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

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

2014-01-01

220

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

PubMed

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

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

2009-11-01

221

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...

222

Characterization of Vibrio tapetis strains isolated from diseased cultured Wedge sole (Dicologoglossa cuneata Moreau).  

PubMed

The first isolation of Vibrio tapetis from Wedge sole (Dicologoglossa cuneata) is reported. The bacterium was recovered from ulcers of ailing cultured fish, from two different outbreaks occurred in spring 2005. The four isolates found (a200, a201, a204 and a255) were biochemically, genetically and serologically characterized and diagnosis was confirmed by PCR V. tapetis specific primers and multilocus sequencing analysis (MLSA). The isolates constituted a homogeneous phenotypic and genotypic group, being distinct to the already serological and genetic groups defined within the species. A virulence evaluation of the isolate a255 was also carried out; however this strain was unable to induce disease in fry and juvenile Wedge sole. PMID:20557916

López, J R; Balboa, S; Núñez, S; de la Roca, E; de la Herran, R; Navas, J I; Toranzo, A E; Romalde, J L

2011-04-01

223

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

PubMed Central

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

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

2014-01-01

224

Zebrafish as a natural host model for Vibrio cholerae colonization and transmission.  

PubMed

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

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

2014-03-01

225

Preventing Maritime Transfer of Toxigenic Vibrio cholerae  

PubMed Central

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

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

2012-01-01

226

Preventing maritime transfer of toxigenic Vibrio cholerae.  

PubMed

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

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

2012-10-01

227

Vibrio parahaemolyticus cell biology and pathogenicity determinants  

PubMed Central

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

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

2011-01-01

228

Evidence for the role of horizontal transfer in generating pVT1, a large mosaic conjugative plasmid from the clam pathogen, Vibrio tapetis.  

PubMed

The marine bacterium Vibrio tapetis is the causative agent of the brown ring disease, which affects the clam Ruditapes philippinarum and causes heavy economic losses in North of Europe and in Eastern Asia. Further characterization of V. tapetis isolates showed that all the investigated strains harbored at least one large plasmid. We determined the sequence of the 82,266 bp plasmid pVT1 from the CECT4600(T) reference strain and analyzed its genetic content. pVT1 is a mosaic plasmid closely related to several conjugative plasmids isolated from Vibrio vulnificus strains and was shown to be itself conjugative in Vibrios. In addition, it contains DNA regions that have similarity with several other plasmids from marine bacteria (Vibrio sp., Shewanella sp., Listonella anguillarum and Photobacterium profundum). pVT1 contains a number of mobile elements, including twelve Insertion Sequences or inactivated IS genes and an RS1 phage element related to the CTXphi phage of V. cholerae. The genetic organization of pVT1 underscores an important role of horizontal gene transfer through conjugative plasmid shuffling and transposition events in the acquisition of new genetic resources and in generating the pVT1 modular organization. In addition, pVT1 presents a copy number of 9, relatively high for a conjugative plasmid, and appears to belong to a new type of replicon, which may be specific to Vibrionaceae and Shewanelleacae. PMID:21326607

Erauso, Gaël; Lakhal, Fatma; Bidault-Toffin, Adeline; Le Chevalier, Patrick; Bouloc, Philippe; Paillard, Christine; Jacq, Annick

2011-01-01

229

Salmonella typhimurium Recognizes a Chemically Distinct Form of the Bacterial Quorum-Sensing Signal AI2  

Microsoft Academic Search

Bacterial populations use cell-cell communication to coordinate community-wide regulation of processes such as biofilm formation, virulence, and bioluminescence. This phenomenon, termed quorum sensing, is mediated by small molecule signals known as autoinducers. While most autoinducers are species specific, autoinducer-2 (AI-2), first identified in the marine bacterium Vibrio harveyi, is produced and detected by many Gram-negative and Gram-positive bacteria. The crystal

Stephen T. Miller; Karina B. Xavier; Shawn R. Campagna; Michiko E. Taga; Martin F. Semmelhack; Bonnie L. Bassler; Frederick M. Hughson

2004-01-01

230

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

PubMed

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

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

2015-01-01

231

A medium for presumptive identification of Vibrio anguillarum.  

PubMed Central

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

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

1994-01-01

232

Mechanistic insights into filamentous phage integration in Vibrio cholerae.  

PubMed

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

Das, Bhabatosh

2014-01-01

233

Genome assortment, not serogroup, defines Vibrio cholerae pandemic strains  

SciTech Connect

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.

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

2009-01-01

234

Mechanistic insights into filamentous phage integration in Vibrio cholerae  

PubMed Central

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

Das, Bhabatosh

2014-01-01

235

Occurrence, Diversity, and Pathogenicity of Halophilic Vibrio spp. and Non-O1 Vibrio cholerae from Estuarine Waters along the Italian Adriatic Coast  

Microsoft Academic Search

The occurrence, diversity, and pathogenicity of Vibrio spp. were investigated in two estuaries along the Italian Adriatic coast. Vibrio alginolyticus was the predominant species, followed by Vibrio parahaemolyticus, non-O1 Vibrio cholerae, and Vibrio vulnificus. By using a biochemical fingerprinting method, all isolates were grouped into nine phenotypes with similarity levels of 75 to 97.5%. The production of toxins capable of

ELENA BARBIERI; LOREDANA FALZANO; CARLA FIORENTINI; ANNA PIANETTI; WALLY BAFFONE; ALESSIA FABBRI; PAOLA MATARRESE; ANNARITA CASIERE; MOHAMMAD KATOULI; INGER KUHN; ROLAND MOLLBY; FRANCESCA BRUSCOLINI; GIANFRANCO DONELLI

1999-01-01

236

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

PubMed

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

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

2014-10-01

237

Transformation Experiment Using Bioluminescence Genes of "Vibrio fischeri."  

ERIC Educational Resources Information Center

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)

Slock, James

1995-01-01

238

Vibrios associated with red tides caused by Mesodinium rubrum.  

PubMed Central

Vibrios were isolated from red tides caused by Mesodinium rubrum and also throughout the year in the Ria de Pontevedra, Spain. The isolates were grouped into 14 phena by numerical toxonomy. Strains associated with red tides were restricted to four phena: phena I and II were Vibrio alginolyticus, and phena III and IV were Vibrio tubiashii and Vibrio anguillarum, respectively. V. anguillarum-like strains (phena V through XI) predominated throughout the year outside the red tide areas. Cytotoxicity assays conducted in different poikilothermic and homoiothermic cell lines showed that cytotoxin production was not necessarily associated with the species selected during the red tides. PMID:2268167

Romalde, J L; Barja, J L; Toranzo, A E

1990-01-01

239

Pierce's disease of grapevines: isolation of the causal bacterium.  

PubMed

A Gram-negative, rod-shaped bacterium has been consistently isolated from grapevines with Pierce's disease. Grapevines inoculated with the bacterium developed Pierce's disease, and the bacterium was reisolated from the plants. The bacterium was serologically and ultrastructurallv indistinguishable from the one in naturally infected plants, and also indistinguishable from a bacterium isolated from almonds with almond leaf scorch disease. PMID:17569487

Davis, M J; Purcell, A H; Thomson, S V

1978-01-01

240

Structural and regulatory mutations in Vibrio parahaemolyticus type III secretion systems display variable effects on virulence.  

PubMed

The Gram-negative bacterium, Vibrio parahaemolyticus, is a major cause of seafood-derived food poisoning throughout the world. The pathogenicity of V. parahaemolyticus is attributed to several virulence factors, including two type III secretion systems (T3SS), T3SS1 and T3SS2. Herein, we compare the virulence of V. parahaemolyticus POR strains, which harbor a mutation in the T3SS needle apparatus of either system, to V. parahaemolyticus CAB strains, which harbor mutations in positive transcriptional regulators of either system. These strains are derived from the clinical RIMD 2210633 strain. We demonstrate that each mutation affects the virulence of the bacterium in a different manner. POR and CAB strains exhibited similar levels of swarming motility and T3SS effector production and secretion, but the CAB3 and CAB4 strains, which harbor a mutation in the T3SS2 master regulator gene, formed reduced biofilm growth under T3SS2 inducing conditions. Additionally, while the cytotoxicity of the POR and CAB strains was similar, the CAB2 (T3SS1 regulatory mutant) strain was strikingly more invasive than the comparable POR2 (T3SS1 structural mutant) strain. In summary, creating structural or regulatory mutations in either T3SS1 or T3SS2 causes differential downstream effects on other virulence systems. Understanding the biological differences of strains created from a clinical isolate is critical for interpreting and understanding the pathogenic nature of V. parahaemolyticus. PMID:25288215

Calder, Thomas; de Souza Santos, Marcela; Attah, Victoria; Klimko, John; Fernandez, Jessie; Salomon, Dor; Krachler, Anne-Marie; Orth, Kim

2014-12-01

241

Heterogeneous Response to a Quorum-Sensing Signal in the Luminescence of Individual Vibrio fischeri  

PubMed Central

The marine bacterium Vibrio fischeri regulates its bioluminescence through a quorum sensing mechanism: the bacterium releases diffusible small molecules (autoinducers) that accumulate in the environment as the population density increases. This accumulation of autoinducer (AI) eventually activates transcriptional regulators for bioluminescence as well as host colonization behaviors. Although V.fischeri quorum sensing has been extensively characterized in bulk populations, far less is known about how it performs at the level of the individual cell, where biochemical noise is likely to limit the precision of luminescence regulation. We have measured the time-dependence and AI-dependence of light production by individual V.fischeri cells that are immobilized in a perfusion chamber and supplied with a defined concentration of exogenous AI. We use low-light level microscopy to record and quantify the photon emission from the cells over periods of several hours as they respond to the introduction of AI. We observe an extremely heterogeneous response to the AI signal. Individual cells differ widely in the onset time for their luminescence and in their resulting brightness, even in the presence of high AI concentrations that saturate the light output from a bulk population. The observed heterogeneity shows that although a given concentration of quorum signal may determine the average light output from a population of cells, it provides far weaker control over the luminescence output of each individual cell. PMID:21103327

Pérez, Pablo Delfino; Hagen, Stephen J.

2010-01-01

242

Vibrio fluvialis: an emerging human pathogen.  

PubMed

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

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

2014-01-01

243

Vibrio cholerae: Measuring Natural Transformation Frequency.  

PubMed

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. © 2014 by John Wiley & Sons, Inc. PMID:25367272

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

2014-01-01

244

Vibrio fluvialis: an emerging human pathogen  

PubMed Central

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

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

2014-01-01

245

Localized Quorum Sensing in Vibrio fischeri  

Microsoft Academic Search

Quorum sensing is almost always regarded as a population density effect in three-dimensional bulk samples of bacteria. Here we create two-dimensional samples of Vibrio fischeri cells adhered onto glass surfaces to examine the effect of local population densities on quorum sensing. This is done by measuring the luminescent response. The 2-D bacterial populations enable us to simultaneously account for time

Mary E. Parent; Charles E. Snyder; Nathaniel D. Kopp; Darrell Velegol

2008-01-01

246

Extended serotyping scheme for Vibrio cholerae  

Microsoft Academic Search

Fifty-seven new O serogroups have been added to the existing serotyping scheme ofVibrio cholerae to extend the scheme from O84 to O140. Prominent new additions were serogroups O139 and O140. The reference strain of O139 was isolated from a patient from an epidemic of cholera-like diarrhea in Madras, Southern India. Serogroup O140 was assigned to a group ofV. cholerae strains

Toshio Shimada; Eiji Arakawa; Kenichiro Itoh; Tadayuki Okitsu; Akiyoshi Matsushima; Yoshio Asai; Shiro Yamai; Tamotsu Nakazato; G. Balakrish Nair; M. John Albert; Yoshifumi Takeda

1994-01-01

247

Vibrio sp. strain NM 10, isolated from the intestine of a Japanese coastal fish, has an inhibitory effect against Pasteurella piscicida.  

PubMed Central

Vibrio sp. strain NM 10 with an inhibitory activity against Pasteurella piscicida K-III was isolated from the intestine of a spotnape ponyfish (Leiognathus nuchalis). This bacterium efficiently produced an antibacterial substance after growth at 20 degrees C for 24 h on 1/5 PYBG agar prepared with 50% seawater at pHs of 7.5 to 9.0. The antibacterial substance was heat labile and proteinaceous, with a molecular mass of less than 5 kDa, possibly a bacteriocin or a bacteriocin-like substance. PMID:9406423

Sugita, H; Matsuo, N; Hirose, Y; Iwato, M; Deguchi, Y

1997-01-01

248

Vibrio sp. strain NM 10, isolated from the intestine of a Japanese coastal fish, has an inhibitory effect against Pasteurella piscicida.  

PubMed

Vibrio sp. strain NM 10 with an inhibitory activity against Pasteurella piscicida K-III was isolated from the intestine of a spotnape ponyfish (Leiognathus nuchalis). This bacterium efficiently produced an antibacterial substance after growth at 20 degrees C for 24 h on 1/5 PYBG agar prepared with 50% seawater at pHs of 7.5 to 9.0. The antibacterial substance was heat labile and proteinaceous, with a molecular mass of less than 5 kDa, possibly a bacteriocin or a bacteriocin-like substance. PMID:9406423

Sugita, H; Matsuo, N; Hirose, Y; Iwato, M; Deguchi, Y

1997-12-01

249

Detection and differentiation of Vibrio spp. in seafood and fish samples with cultural and molecular methods  

Microsoft Academic Search

Vibrio spp. as natural inhabitants of sea- and brackwater of both tropical and temperate regions of the world are commonly found in different kinds of seafood. Even among the three main human pathogenic species Vibrio parahaemolyticus, Vibrio cholerae and Vibrio vulnificus most of the isolates from seafood do not carry the different virulence factors responsible for foodborne infections. Therefore, the

U. Messelhäusser; J. Colditz; D. Thärigen; W. Kleih; C. Höller; U. Busch

2010-01-01

250

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

PubMed Central

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.

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

2015-01-01

251

ORIGINAL ARTICLE Phylogeny and fitness of Vibrio fischeri from the  

E-print Network

The bioluminescent, heterotrophic marine bacter- ium Vibrio fischeri (Gammaproteobacteria: Vibrio- naceae) maintains). The host animals are hypothesized to receive a behavioral benefit from bacterial bioluminescence, whereas the bacteria are hypothesized to receive a metabolic benefit from the host (Stabb and Millikan, 2009

McFall-Ngai, Margaret

252

Genome Sequence of Vibrio rotiferianus Strain DAT722?  

PubMed Central

Vibrio rotiferianus is a marine pathogen capable of causing disease in various aquatic organisms. We announce the genome sequence of V. rotiferianus DAT722, which has a large chromosomal integron containing 116 gene cassettes and is a model organism for studying the role of this system in vibrio evolution. PMID:21551292

Chowdhury, Piklu Roy; Boucher, Yan; Hassan, Karl A.; Paulsen, Ian T.; Stokes, H. W.; Labbate, Maurizio

2011-01-01

253

Vibrio cholerae Proteome-Wide Screen for Immunostimulatory Proteins Identifies  

E-print Network

Vibrio cholerae Proteome-Wide Screen for Immunostimulatory Proteins Identifies Phosphatidylserine Activators. Out of 3,882 Vibrio cholerae proteins, we identified phosphatidylserine decarboxylase (PSD. cholerae PSD as a novel TLR4 agonist and further demonstrate the potential application of PSD as a vaccine

Mekalanos, John

254

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

SciTech Connect

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.

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

2006-01-01

255

Vibrio diversity and dynamics in the Monterey Bay upwelling region  

PubMed Central

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

Mansergh, Sarah; Zehr, Jonathan P.

2013-01-01

256

Evaluation of a new chromogenic medium, chromID™ Vibrio, for the isolation and presumptive identification of Vibrio cholerae and Vibrio parahaemolyticus from human clinical specimens  

Microsoft Academic Search

The aim of this study was to evaluate the performance of the chromID™ Vibrio medium for the detection of Vibrio cholerae and V. parahaemolyticus in stool and swab specimens in comparison with thiosulfate citrate bile salts sucrose (TCBS) medium. A total of 96 samples\\u000a including 30 fresh stool, 32 stool, and 34 swab specimens originating from routine laboratories were tested.

R. Eddabra; Y. Piemont; J. M. Scheftel

2011-01-01

257

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

PubMed Central

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

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

2013-01-01

258

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

PubMed Central

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

2013-01-01

259

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

SciTech Connect

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.

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

2010-03-04

260

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

PubMed Central

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 ? 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. PMID:20133655

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

2010-01-01

261

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

PubMed

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 A 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. PMID:20133655

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

2010-02-16

262

Glucose- but not rice-based oral rehydration therapy enhances the production of virulence determinants in the human pathogen Vibrio cholerae.  

PubMed

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

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

2014-12-01

263

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

PubMed Central

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

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

2014-01-01

264

Central role of the Na+-translocating NADH:quinone oxidoreductase (Na+-NQR) in sodium bioenergetics of Vibrio cholerae.  

PubMed

Abstract Vibrio cholerae is a Gram-negative bacterium that lives in brackish or sea water environments. Strains of V. cholerae carrying the pathogenicity islands infect the human gut and cause the fatal disease cholera. Vibrio cholerae maintains a Na+ gradient at its cytoplasmic membrane that drives substrate uptake, motility, and efflux of antibiotics. Here, we summarize the major Na+-dependent transport processes and describe the central role of the Na+-translocating NADH:quinone oxidoreductase (Na+-NQR), a primary Na+ pump, in maintaining a Na+-motive force. The Na+-NQR is a membrane protein complex with a mass of about 220 kDa that couples the exergonic oxidation of NADH to the transport of Na+ across the cytoplasmic membrane. We describe the molecular architecture of this respiratory complex and summarize the findings how electron transport might be coupled to Na+-translocation. Moreover, recent advances in the determination of the three-dimensional structure of this complex are reported. PMID:25205724

Steuber, Julia; Halang, Petra; Vorburger, Thomas; Steffen, Wojtek; Vohl, Georg; Fritz, Günter

2014-12-01

265

Comparative Evolutionary Analysis of the Major Structural Subunit of Vibrio vulnificus Type IV Pili  

PubMed Central

Type IV pili contribute to virulence in Vibrio vulnificus, the bacterium responsible for the majority of fatal seafood-related infections. Here, we performed within- and between-species evolutionary analysis of the gene that encodes the major structural subunit of the pilus, pilA, by comparing it with pilD and gyrB, the genes encoding the type IV prepilin peptidase and ? subunit of DNA gyrase, respectively. Although the diversity in pilD and gyrB is similar to each other and likely to have accumulated after speciation of V. vulnificus, pilA is several times more diverse at both nonsynonymous and synonymous levels. Also, in contrast to pilD and gyrB, there are virtually unrestricted and highly localized horizontal movements of pilA alleles between the major phylogenetic groups of V. vulnificus. The frequent movement of pilA involves homologous recombination of the entire gene with no evidence for intragenic recombination between the alleles. We propose that pilA allelic diversity and horizontal movement is maintained in the population by both diversifying and frequency-dependent selection most likely to escape shellfish innate immunity defense or lytic phages. Other possibilities leading to such selection dynamics of V. vulnificus pilA could involve adaptation to diverse host populations or within-host compartments, or natural DNA uptake and transformation. We show that the history of nucleotide diversification in pilA predates V. vulnificus speciation and this diversification started at or before the time of the last common ancestor for V. vulnificus, Vibrio parahaemolyticus, and Vibrio cholerae. At the same time, it appears that within the various pilA groups of V. vulnificus, there is no positive selection for structural mutations and consequently no evidence for source–sink selection. In contrast, pilD has accumulated a number of apparently adaptive mutations in the regions encoding the membrane-spanning portions of the prepilin peptidase, possibly affecting fimbrial expression and/or function, and is being subjected to source–sink selection dynamics. PMID:19556347

Chattopadhyay, Sujay; Paranjpye, Rohinee N.; Dykhuizen, Daniel E.; Sokurenko, Evgeni V.; Strom, Mark S.

2009-01-01

266

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

PubMed

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

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

2014-10-01

267

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

PubMed Central

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

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

2011-01-01

268

Antibiotic Resistant Salmonella and Vibrio Associated with Farmed Litopenaeus vannamei  

PubMed Central

Salmonella and Vibrio species were isolated and identified from Litopenaeus vannamei cultured in shrimp farms. Shrimp samples showed occurrence of 3.3% of Salmonella and 48.3% of Vibrio. The isolates were also screened for antibiotic resistance to oxolinic acid, sulphonamides, tetracycline, sulfamethoxazole/trimethoprim, norfloxacin, ampicillin, doxycycline hydrochloride, erythromycin, chloramphenicol, and nitrofurantoin. Salmonella enterica serovar Corvallis isolated from shrimp showed individual and multiple antibiotic resistance patterns. Five Vibrio species having individual and multiple antibiotic resistance were also identified. They were Vibrio cholerae (18.3%), V. mimicus (16.7%), V. parahaemolyticus (10%), V. vulnificus (6.7%), and V. alginolyticus (1.7%). Farm owners should be concerned about the presence of these pathogenic bacteria which also contributes to human health risk and should adopt best management practices for responsible aquaculture to ensure the quality of shrimp. PMID:22619583

Banerjee, Sanjoy; Ooi, Mei Chen; Shariff, Mohamed; Khatoon, Helena

2012-01-01

269

Natural transformation of a marine Vibrio species by plasmid DNA  

Microsoft Academic Search

Vibrio sp. DI9, recently isolated from Tampa Bay, FL, has been found to be naturally transformed by the broad host range plasmid pKT230 in both filter transformation assays and sterile sediment microcosms. This is the first report of natural transformation by plasmid DNA of aVibrio sp. and of a marine bacterial isolate. Transformation frequencies ranged from 0.3 to 3.1×10?8 transformants

Wade H. Jeffrey; John H. Paul; Gregory J. Stewart

1990-01-01

270

Diversity and Genetic Basis of Polysaccharide Biosynthesis in Vibrio cholerae  

Microsoft Academic Search

\\u000a \\u000a Vibrio cholerae elaborates three types of polysaccharide structures: lipopolysaccharide (LPS), a component of which is the O-polysaccharide\\u000a or O-antigen, capsular polysaccharide (CPS) or K-antigen, and “rugose” polysaccharide also known as exopolysaccharide (EPS)\\u000a or Vibrio polysaccharide (VPS). The major protective antigen for V. cholerae is the O-antigen. A strain typing scheme based on the somatic O-antigen has been in use for

Shanmuga Sozhamannan; Fitnat H. Yildiz

271

Oligotyping reveals community level habitat selection within the genus Vibrio  

PubMed Central

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

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

2014-01-01

272

Quorum Sensing-Dependent Biofilms Enhance Colonization in Vibrio cholerae  

Microsoft Academic Search

Vibrio cholerae is the causative agent of the diarrheal disease cholera. By an incompletely understood developmental process, V. cholerae forms complex surface-associated communities called biofilms. Here we show that quorum sensing-deficient mutants of V. cholerae produce thicker biofilms than those formed by wild-type bacteria. Microarray analysis of biofilm-associated bacteria shows that expression of the Vibrio polysaccharide synthesis (vps) operons is

Jun Zhu; John J. Mekalanos

2003-01-01

273

Draft Genome Sequence of the Purple Photosynthetic Bacterium Phaeospirillum molischianum DSM120, a Particularly Versatile Bacterium  

PubMed Central

Here we present the draft genome sequence of the versatile and adaptable purple photosynthetic bacterium Phaeospirillum molischianum DSM120. This study advances the understanding of the adaptability of this bacterium, as well as the differences between the Phaeospirillum and Rhodospirillum genera. PMID:22689244

Prima, V.; Ji, B.; Rouy, Z.; Médigue, C.; Talla, E.; Sturgis, J. N.

2012-01-01

274

The Regulatory Network of Natural Competence and Transformation of Vibrio cholerae  

PubMed Central

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

Lo Scrudato, Mirella; Blokesch, Melanie

2012-01-01

275

Vibrio cholerae: lessons for mucosal vaccine design  

PubMed Central

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

Bishop, Anne L; Camilli, Andrew

2011-01-01

276

Viscosity dictates metabolic activity of Vibrio ruber.  

PubMed

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

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

2012-01-01

277

Vibriobactin, a siderophore from Vibrio cholerae.  

PubMed

A novel siderophore (microbial iron transport compound) has been isolated from low iron cultures of Vibrio cholerae. Belonging to the catecholamide family of chelators, it has been shown to contain three residues of 2,3-dihydroxybenzoic acid and two residues of threonine. Both threonine moieties are present in the form of oxazoline rings. Furthermore, the polyamine backbone of the molecule was proved to be not spermidine, but the rare N-(3-aminopropyl)-1,3-diaminopropane, norspermidine. The structure of the new siderophore has been determined to be N-[3-(2,3-dihydroxybenzamido)propyl]-1, 3-bis[2,3-dihydroxyphenyl)-trans-5-methyl-2-oxazoline-4-carboxamido]prop ane. The compound has been given the trivial name vibriobactin. Mutants defective in the synthesis and utilization of vibriobactin were isolated. In an iron-limited environment V. cholerae was found to respond more strongly to vibriobactin, agrobactin, and ferrichrome than to enterobactin. PMID:6706943

Griffiths, G L; Sigel, S P; Payne, S M; Neilands, J B

1984-01-10

278

Impact of mucin, bile salts and cholesterol on the virulence of Vibrio anguillarum towards gnotobiotic sea bass (Dicentrarchus labrax) larvae.  

PubMed

In this study, we investigated the impact of the host factors mucin, bile salts and cholesterol on the virulence of the economically important aquatic pathogen Vibrio anguillarum towards sea bass larvae. Pretreatment of V. anguillarum with either one of the host factors (at 10mgl(-1)) prior to inoculation into the sea bass rearing water increased virulence of the bacterium, although the effect of cholesterol was not significant. Each of the three host factors significantly increased several virulence-related phenotypes in V. anguillarum, i.e. protease activity, flagellar motility, biofilm formation and exopolysaccharide production, whereas there was no effect on growth of the bacterium under these conditions. Furthermore, the host factors increased the expression of genes involved in these phenotypes, i.e. the metalloprotease empA, the flagellar transcriptional regulator fleQ, the flagellin gene flaA, the chemotaxis methyltransferase gene cheR, the exopolysaccharide biosynthesis gene wbfD and the exopolysaccharide export gene wza. Our results indicate that V. anguillarum uses host mucin, bile salts, and cholesterol as cues to promote the expression of several important virulence traits that enhance the success of transmission from one host to another. PMID:25465176

Li, Xuan; Bossier, Peter; Dierckens, Kristof; Laureau, Stanislas; Defoirdt, Tom

2015-01-30

279

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

PubMed Central

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

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

2012-01-01

280

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

PubMed Central

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

de Souza Santos, Marcela

2014-01-01

281

In-vitro anti- Vibrio spp. activity and chemical composition of some Tunisian aromatic plants  

Microsoft Academic Search

The chemical composition of five aromatic plants (Mentha longifolia, M. pulegium, Eugenia caryophyllata, Thymus vulgaris and Rosmarinus officinalis) frequently used in food preparation in Tunisia was analysed by GC-MS. The antimicrobial effect of the essential oils obtained\\u000a from these plants was tested against Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio fluvialis strains. Thyme oil exhibited a high level of

Mejdi Snoussi; Hafedh Hajlaoui; Emira Noumi; Donatella Usai; Leonardo Antonio Sechi; Stefania Zanetti; Amina Bakhrouf

2008-01-01

282

Enhanced Cellular Immunity in Shrimp (Litopenaeus vannamei) after ‘Vaccination’  

PubMed Central

It has long been viewed that invertebrates rely exclusively upon a wide variety of innate mechanisms for protection from disease and parasite invasion and lack any specific acquired immune mechanisms comparable to those of vertebrates. Recent findings, however, suggest certain invertebrates may be able to mount some form of specific immunity, termed ‘specific immune priming’, although the mechanism of this is not fully understood (see Textbox S1). In our initial experiments, either formalin-inactivated Vibrio harveyi or sterile saline were injected into the main body cavity (haemocoel) of juvenile shrimp (Litopenaeus vannamei). Haemocytes (blood cells) from V. harveyi-injected shrimp were collected 7 days later and incubated with a 1?1 mix of V. harveyi and an unrelated Gram positive bacterium, Bacillus subtilis. Haemocytes from ‘vaccinated’ shrimp showed elevated levels of phagocytosis of V. harveyi, but not B. subtilis, compared with those from saline-injected (non-immunised) animals. The increased phagocytic activity was characterised by a significant increase in the percentage of phagocytic cells. When shrimp were injected with B. subtilis rather than vibrio, there was no significant increase in the phagocytic activity of haemocytes from these animals in comparison to the non-immunised (saline injected) controls. Whole haemolymph (blood) from either ‘immunised’ or non-immunised’ shrimp was shown to display innate humoral antibacterial activity against V. harveyi that was absent against B. subtilis. However, there was no difference in the potency of antibacterial activity between V. harveyi-injected shrimp and control (saline injected) animals showing that ‘vaccination’ has no effect on this component of the shrimp's immune system. These results imply that the cellular immune system of shrimp, particularly phagocytosis, is capable of a degree of specificity and shows the phenomenon of ‘immune priming’ reported by other workers. However, in agreement with other studies, this phenomenon is not universal to all potential pathogens. PMID:21698190

Roberts, Emily C.; Shields, Robin J.; Wardle, Robin; Rowley, Andrew F.

2011-01-01

283

Identifying the cellular mechanisms of symbiont-induced epithelial morphogenesis in the squid-vibrio association  

PubMed Central

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

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

2014-01-01

284

Small-Molecule Inhibitors of toxT Expression in Vibrio cholerae  

PubMed Central

ABSTRACT Vibrio cholerae, a Gram-negative bacterium, infects humans and causes cholera, a severe disease characterized by vomiting and diarrhea. These symptoms are primarily caused by cholera toxin (CT), whose production by V. cholerae is tightly regulated by the virulence cascade. In this study, we designed and carried out a high-throughput chemical genetic screen to identify inhibitors of the virulence cascade. We identified three compounds, which we named toxtazin A and toxtazin B and B?, representing two novel classes of toxT transcription inhibitors. All three compounds reduce production of both CT and the toxin-coregulated pilus (TCP), an important colonization factor. We present evidence that toxtazin A works at the level of the toxT promoter and that toxtazins B and B? work at the level of the tcpP promoter. Treatment with toxtazin B results in a 100-fold reduction in colonization in an infant mouse model of infection, though toxtazin A did not reduce colonization at the concentrations tested. These results add to the growing body of literature indicating that small-molecule inhibitors of virulence genes could be developed to treat infections, as alternatives to antibiotics become increasingly needed. PMID:23919997

Anthouard, Rebecca; DiRita, Victor J.

2013-01-01

285

The Mannose-Sensitive Hemagglutinin of Vibrio cholerae Promotes Adherence to Zooplankton  

PubMed Central

The bacterium Vibrio cholerae, the etiological agent of cholera, is often found attached to plankton, a property that is thought to contribute to its environmental persistence in aquatic habitats. The V. cholerae O1 El Tor biotype and V. cholerae O139 strains produce a surface pilus termed the mannose-sensitive hemagglutinin (MSHA), whereas V. cholerae O1 classical biotype strains do not. Although V. cholerae O1 classical does not elaborate MSHA, the gene is present and expressed at a level comparable to that of the other strains. Since V. cholerae O1 El Tor and V. cholerae O139 have displaced V. cholerae O1 classical as the major epidemic strains over the last fifteen years, we investigated the potential role of MSHA in mediating adherence to plankton. We found that mutation of mshA in V. cholerae O1 El Tor significantly diminished, but did not eliminate, adherence to exoskeletons of the planktonic crustacean Daphnia pulex. The effect of the mutation was more pronounced for V. cholerae O139, essentially eliminating adherence. Adherence of the V. cholerae O1 classical mshA mutant was unaffected. The results suggest that MSHA is a factor contributing to the ability of V. cholerae to adhere to plankton. The results also showed that both biotypes of V. cholerae O1 utilize factors in addition to MSHA for zooplankton adherence. The expression of MSHA and these additional, yet to be defined, adherence factors differ in a serogroup- and biotype-specific manner. PMID:11425745

Chiavelli, Deborah A.; Marsh, Jane W.; Taylor, Ronald K.

2001-01-01

286

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

PubMed

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

Ray, Valerie A; Driks, Adam; Visick, Karen L

2015-02-01

287

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

PubMed Central

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

Koestler, Benjamin J.

2014-01-01

288

Low Dose Gamma Irradiation to Reduce Pathogenic Vibrios in Live Oysters (Crassostrea virginica)  

Microsoft Academic Search

Pathogenic strains of Vibrio (Vibrio vulnificus and V. parahaemolyticus), natural inhabitants of estuarine and ocean environments, can cause serious illness and death in susceptible persons from consumption of raw half-shell oysters. Objectives of this study were (1) to establish the irradiation dose needed to reduce pathogenic vibrios to nondetectable levels and (2) to determine consumer's ability to differentiate between irradiated

Linda Andrews; Michael Jahncke; Kumar Mallikarjunan

2003-01-01

289

Draft Genome Sequences of Vibrio sp. Strains Isolated from Tetrodotoxin-Bearing Scavenging Gastropod  

PubMed Central

Vibrio sp. strains JCM 18905 and JCM 19053 were isolated from a tetrodotoxin (TTX)-bearing scavenging gastropod, and Vibrio sp. strain JCM 18904 was isolated from a sea cucumber. All these are closely related to Vibrio alginolyticus. Their comparative genome information is useful for studies of TTX production in bacteria. PMID:24948773

Kawauchi, Ayumi; Nakahara, Tomomi; Zhang, Xiaochi; Taniyama, Shigeto; Takatani, Tomohiro; Arakawa, Osamu; Oshima, Kenshiro; Suda, Wataru; Kitamura, Keiko; Iida, Toshiya; Iino, Takao; Inoue, Tetsushi; Hongoh, Yuichi; Hattori, Masahira

2014-01-01

290

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

PubMed

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

Ren, Tingting; Su, Yi-Cheng

2006-08-01

291

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

PubMed Central

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

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

2014-01-01

292

Vibriophages and Their Interactions with the Fish Pathogen Vibrio anguillarum  

PubMed Central

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

Tan, Demeng; Gram, Lone

2014-01-01

293

New Vibrio species associated to molluscan microbiota: a review  

PubMed Central

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

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

2014-01-01

294

[A multipathogen selective enrichment broth (SVV) for simultaneous growth of Salmonella, Vibrio parahaemolyticus, and Vibrio cholerae].  

PubMed

We formulated a selective enrichment broth (SVV) for simultaneous growth of Salmonella, Vibrio parahaemolyticus, and Vibrio cholerae by single factor experiment and response surface method. We evaluated the enrichment effect of SVV by conventional culture method and real-time PCR assay. We obtained the SVV broth by supplementting the Buffered Peptone Water (BPW) with bile salt no. 3, potassium tellurite, and sodium citrate as inhibitors, and glucose, mannitol, snhydrous sodium sulfite and sodium pyruvate as accelerants. We also modified the concentration of sodium chloride in BPW. When mixed at equal or varied proportions, the target pathogens had a great accumulation (10(5)-10(8) CFU/mL) after incubated in SVV for 18 h at 37 degrees C with shaking. It can also effectively inhibit the competitive microflora. We detected 10 artificial simulated samples and 608 real samples using SVV with real-time PCR. After enriched in SVV for 18 h, the quantity of the bacteria in samples were above the detection limit. The SVV with PCR assay showed higher tested positive (4.06%) compared to that of the conventional detection method (3.78%) and there was no false report. In summary, SVV is a promising new multiplex selective enrichment broth that can be used in detection of seafood. PMID:20112694

Qin, Yiying; Wu, Hui; Xiao, Xinglong; Yu, Yigang; Liu, Dongmei; Li, Xiaofeng; Tang, Yuqian

2009-10-01

295

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

PubMed Central

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

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

2010-01-01

296

Dynamics in genome evolution of Vibrio cholerae.  

PubMed

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

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

2014-04-01

297

Cell Vacuolation Caused by Vibrio cholerae Hemolysin  

PubMed Central

Non-O1 strains of Vibrio cholerae implicated in gastroenteritis and diarrhea generally lack virulence determinants such as cholera toxin that are characteristic of epidemic strains; the factors that contribute to their virulence are not understood. Here we report that at least one-third of diarrhea-associated nonepidemic V. cholerae strains from Mexico cause vacuolation of cultured Vero cells. Detailed analyses indicated that this vacuolation was related to that caused by aerolysin, a pore-forming toxin of Aeromonas; it involved primarily the endoplasmic reticulum at early times (?1 to 4 h after exposure), and resulted in formation of large, acidic, endosome-like multivesicular vacuoles (probably autophagosomes) only at late times (?16 h). In contrast to vacuolation caused by Helicobacter pylori VacA protein, that induced by V. cholerae was exacerbated by agents that block vacuolar proton pumping but not by endosome-targeted weak bases. It caused centripetal redistribution of endosomes, reflecting cytoplasmic alkalinization. The gene for V. cholerae vacuolating activity was cloned and was found to correspond to hlyA, the structural gene for hemolysin. HlyA protein is a pore-forming toxin that causes ion leakage and, ultimately, eukaryotic cell lysis. Thus, a distinct form of cell vacuolation precedes cytolysis at low doses of hemolysin. We propose that this vacuolation, in itself, contributes to the virulence of V. cholerae strains, perhaps by perturbing intracellular membrane trafficking or ion exchange in target cells and thereby affecting local intestinal inflammatory or other defense responses. PMID:11179335

Figueroa-Arredondo, Paula; Heuser, John E.; Akopyants, Natalia S.; Morisaki, J. Hiroshi; Giono-Cerezo, Silvia; Enríquez-Rincón, Fernando; Berg, Douglas E.

2001-01-01

298

Mechanism of Vibrio cholerae autoinducer-1 biosynthesis.  

PubMed

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

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

2011-04-15

299

GOING AGAINST THE GRAIN: CHEMOTAXIS AND INFECTION IN VIBRIO CHOLERAE  

PubMed Central

Chemotaxis is the process by which motile cells move in a biased manner both towards favourable and away from unfavourable environments. The requirement of this process for infection has been examined in several bacterial pathogens, including Vibrio cholerae. The single polar flagellum of Vibrio species is powered by a sodium-motive force across the inner membrane, and can rotate to produce speeds of up to 60 cell-body lengths (~60µm) per second. Investigating the role of the chemotactic control of rapid flagellar motility during V. cholerae infection has revealed some unexpected and intriguing results. PMID:16012515

Butler, Susan M.; Camilli, Andrew

2009-01-01

300

Pyrosequencing-Based Comparative Genome Analysis of Vibrio vulnificus Environmental Isolates  

PubMed Central

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

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

301

Swimming efficiency of bacterium Escherichia coli  

PubMed Central

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

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

2006-01-01

302

A New, Mushroom-shaped Budding Bacterium  

Microsoft Academic Search

A mushroom-shaped budding bacterium, isolated from fresh pond water, is unlike any previously described aquatic budding bacteria (Whittenbury & McLee, I 967 ; Hirsch & Rheinheimer, 1968 ; Staley, 1968). Its morphological 'life-cycle' and other properties are described. METHODS Media. The organism was grown routinely in glucose-salts medium (pH 6.9) of the follow- ing composition: (NH4)2S04, 0.1 % (w\\/v); NaCI,

R. WHITTENBURY; JUDITH M. NICOLL

1971-01-01

303

Characterization of Tryptophanase from Vibrio cholerae.  

PubMed

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

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

2015-01-01

304

Predictability of Vibrio cholerae in Chesapeake Bay  

PubMed Central

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

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

2003-01-01

305

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

PubMed Central

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

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

1988-01-01

306

Vibrio Trends in the Ecology of the Venice Lagoon  

PubMed Central

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

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

2014-01-01

307

Vibrio parahaemolyticus, Southern Coastal Region of China, 2007–2012  

PubMed Central

We analyzed the prevalence and characteristics of Vibrio parahaemolyticus among patients with acute infectious diarrhea in the southern coastal region of China. V. parahaemolyticus was the leading cause of bacterial infectious diarrhea in this region during 2007–2012. Serotype O3:K6 strains were most common, followed by serotypes O4:K8 and O3:K29. PMID:24655369

Li, Yinghui; Xie, Xu; Shi, Xiaolu; Lin, Yiman; Mou, Jin; Chen, Qiongcheng; Lu, Yan; Zhou, Li; Jiang, Min; Sun, Honghu; Ma, Hanwu; Cheng, Jinquan

2014-01-01

308

Toxigenic Vibrio cholerae O1 in Water and Seafood, Haiti  

PubMed Central

During the 2010 cholera outbreak in Haiti, water and seafood samples were collected to detect Vibrio cholerae. The outbreak strain of toxigenic V. cholerae O1 serotype Ogawa was isolated from freshwater and seafood samples. The cholera toxin gene was detected in harbor water samples. PMID:22099121

Cohen, Nicole; Kahler, Amy M.; Jones, Jessica L.; Bopp, Cheryl A.; Marano, Nina; Tarr, Cheryl L.; Garrett, Nancy M.; Boncy, Jacques; Henry, Ariel; Gómez, Gerardo A.; Wellman, Michael; Curtis, Maurice; Freeman, Molly M.; Turnsek, Maryann; Benner, Ronald A.; Dahourou, Georges; Espey, David; DePaola, Angelo; Tappero, Jordan W.; Handzel, Tom; Tauxe, Robert V.

2011-01-01

309

Draft Genome Sequence of Fish Pathogenic Vibrio vulnificus Biotype 2.  

PubMed

Vibrio vulnificus is a marine pathogen capable of causing severe soft tissue infections and septicemia in humans. V. vulnificus biotype 2 is the etiological agent of fish vibriosis. We describe here the first draft genome sequence of V. vulnificus biotype 2, strain ES-7601, isolated from an infected eel in Japan. PMID:25428972

Koton, Yael; Eghbaria, Saleh; Gordon, Michal; Chalifa-Caspi, Vered; Bisharat, Naiel

2014-01-01

310

Proteomic Analysis of Vibrio cholerae in Human Stool  

Microsoft Academic Search

An effective vaccine for Vibrio cholerae is not yet available for use in the developing world, where the burden of cholera disease is highest. Characterizing the proteins that are expressed by V. cholerae in the human host environment may provide insight into the pathogenesis of cholera and assist with the development of an improved vaccine. We analyzed the V. cholerae

Regina C. LaRocque; Bryan Krastins; Jason B. Harris; Lauren M. Lebrun; Kenneth C. Parker; Michael Chase; Edward T. Ryan; Firdausi Qadri; David Sarracino; Stephen B. Calderwood

2008-01-01

311

Draft Genome Sequence of Fish Pathogenic Vibrio vulnificus Biotype 2  

PubMed Central

Vibrio vulnificus is a marine pathogen capable of causing severe soft tissue infections and septicemia in humans. V. vulnificus biotype 2 is the etiological agent of fish vibriosis. We describe here the first draft genome sequence of V. vulnificus biotype 2, strain ES-7601, isolated from an infected eel in Japan. PMID:25428972

Koton, Yael; Eghbaria, Saleh; Gordon, Michal; Chalifa-Caspi, Vered

2014-01-01

312

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...

313

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 ...

314

Quorum sensing controls biofilm formation in Vibrio cholerae  

Microsoft Academic Search

Summary Multiple quorum-sensing circuits function in parallel to control virulence and biofilm formation in Vibrio cholerae . In contrast to other bacterial pathogens that induce virulence factor production and\\/or biofilm for- mation at high cell density in the presence of quorum- sensing autoinducers, V. cholerae represses these behaviours at high cell density. Consistent with this, we show here that V.

Brian K. Hammer; Bonnie L. Bassler

2003-01-01

315

Characterization of a mutant of Vibrio vulnificus for heme utilization  

Microsoft Academic Search

Vibrio vulnificus, an opportunistic human pathogen, can obtain iron from a variety of heme proteins. This process involves the digestion of heme proteins by an exoprotease to liberate protoheme (iron-protoporphyrin IX). In the present study, we isolated and characterized a mutant for protoheme utilization. One mutant isolated by treatment with a chemical mutagen was shown to be unable to use

Shin-ichi Miyoshi; Yu Inami; Yuko Moriya; Takehito Kamei; Shigeo Yamamoto; Ken-ichi Tomochika; Sumio Shinoda

1997-01-01

316

Vibrio Infections and Surveillance in Maryland, 2002–2008  

PubMed Central

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

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

2013-01-01

317

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

PubMed

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

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

2014-12-01

318

The natural furanone (5Z)-4-bromo-5-(bromomethylene)-3-butyl-2(5H)-furanone disrupts  

E-print Network

many other Gram-negative bacteria, V. harveyi has been reported to use a multichannel quorum sensing disrupts quorum sensing in Vibrio harveyi. Bioluminescence experiments with signal molecule receptor double mutants revealed that the furanone blocks all three channels of the V. harveyi quorum sensing system

Wood, Thomas K.

319

Household Transmission of Vibrio cholerae in Bangladesh  

PubMed Central

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

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

2014-01-01

320

Noise and crosstalk in two quorum-sensing inputs of Vibrio fischeri  

PubMed Central

Background One of the puzzles in bacterial quorum sensing is understanding how an organism integrates the information gained from multiple input signals. The marine bacterium Vibrio fischeri regulates its bioluminescence through a quorum sensing mechanism that receives input from three pheromone signals, including two acyl homoserine lactone (HSL) signals. While the role of the 3-oxo-C6 homoserine lactone (3OC6HSL) signal in activating the lux genes has been extensively studied and modeled, the role of the C8 homoserine lactone (C8HSL) is less obvious, as it can either activate luminescence or block its activation. It remains unclear how crosstalk between C8HSL and 3OC6HSL affects the information that the bacterium obtains through quorum sensing. Results We have used microfluidic methods to measure the response of individual V.fischeri cells to combinations of C8HSL and 3OC6HSL. By measuring the fluorescence of individual V.fischeri cells containing a chromosomal gfp-reporter for the lux genes, we study how combinations of exogenous HSLs affect both the population average and the cell-to-cell variability of lux activation levels. At the level of a population average, the crosstalk between the C8HSL and 3OC6HSL inputs is well-described by a competitive inhibition model. At the level of individual cells, the heterogeneity in the lux response depends only on the average degree of activation, so that the noise in the output is not reduced by the presence of the second HSL signal. Overall we find that the mutual information between the signal inputs and the lux output is less than one bit. A nonlinear correlation between fluorescence and bioluminescence outputs from lux leads to different noise properties for these reporters. Conclusions The lux genes in V.fischeri do not appear to distinguish between the two HSL inputs, and even with two signal inputs the regulation of lux is extremely noisy. Hence the role of crosstalk from the C8HSL input may not be to improve sensing precision, but rather to suppress the sensitivity of the switch for as long as possible during colony growth. PMID:21959018

2011-01-01

321

Vibrio vulnificus Phage PV94 Is Closely Related to Temperate Phages of V. cholerae and Other Vibrio Species  

PubMed Central

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

Reetz, Jochen; Strauch, Eckhard; Hertwig, Stefan

2014-01-01

322

Molecular Typing of Environmental and Clinical Strains of Vibrio vulnificus Isolated in the Northeastern USA  

PubMed Central

Vibrio vulnificus is a ubiquitous marine bacterium that is responsible for infections and some seafood-related illnesses and deaths in the United States, mainly in individuals with compromised health status in the Gulf of Mexico region. Most phylogenetic studies focus on V. vulnificus strains isolated in the southern United States, but almost no genetic data are available on northeastern bacterial isolates of clinical or environmental origin. Our goal in this study was to examine the genetic diversity of environmental strains isolated from commercially-produced oysters and in clinical strains of known pathogenicity in northeastern United States. We conducted analyses of a total of eighty-three strains of V. vulnificus, including 18 clinical strains known to be pathogenic. A polyphasic, molecular-typing approach was carried out, based upon established biotypes, vcg, CPS, 16S rRNA types and three other genes possibly associated with virulence (arylsulfatase A, mtlABC, and nanA). An established Multi Locus Sequence Typing (MLST) method was also performed. Phylogenetic analyses of these markers and MLST results produced similar patterns of clustering of strains into two main lineages (we categorized as ‘LI’ and ‘LII’), with clinical and environmental strains clustering together in both lineages. Lineage LII was comprised primarily but not entirely of clinical bacterial isolates. Putative virulence markers were present in both clinical and environmental strains. These results suggest that some northeastern environmental strains of V. vulnificus are phylogenetically close to clinical strains and probably are capable of virulence. Further studies are necessary to assess the risk of human illness from consuming raw oysters harvested in the northeastern US. PMID:24386187

Reynaud, Yann; Pitchford, Steven; De Decker, Sophie; Wikfors, Gary H.; Brown, Christopher L.

2013-01-01

323

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

PubMed Central

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

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

2014-01-01

324

Marine Lactobacillus pentosus H16 protects Artemia franciscana from Vibrio alginolyticus pathogenic effects.  

PubMed

Vibrio alginolyticus is an opportunistic pathogen which may affect different aquatic organisms. The aim of this study was to assess the probiotic properties and the protective mode of action of Lactobacillus pentosus H16 against V. alginolyticus 03/8525, through in vitro and in vivo studies using Artemia franciscana (hereafter Artemia). This strain showed antimicrobial activity against V. alginolyticus 03/8525 and Aeromonas salmonicida subsp. salmonicida ATCC33658 possibly related to lactobacilli organic acid production. It was able to survive at high rainbow trout bile concentrations and showed high selective adhesion to rainbow trout mucus (1.2 × 105 ± 8.0 × 103 cells cm-2). H16 outcompeted V. alginolyticus 03/8525 and A. salmonicida subsp. salmonicida ATCC33658, greatly reducing their adherence to rainbow trout mucus (64.8 and 74.1%, respectively). Moreover, H16 produced a cell-bound biosurfactant which caused an important decrease in the surface tension. H16 also protected Artemia nauplii against mortality when it was administered previous to V. alginolyticus 03/8525 inoculation. Furthermore, H16 bioencapsulated in Artemia, suggesting that it is possible to use live carriers in its administration. We conclude that the ability of L. pentosus H16 to selectively adhere to mucosal surfaces and produce cell-bound biosurfactants, displacing pathogenic strains, in addition to its antimicrobial activity, confer H16 competitive advantages against pathogens as demonstrated in in vivo challenge experiments. Thus, L. pentosus H16, a marine bacterium from the intestinal tract of hake, is an interesting probiotic for Artemia culture and also has the potential to prevent vibriosis in other aquaculture activities such as larvae culture and fish farming. PMID:25667335

Garcés, M E; Sequeiros, C; Olivera, N L

2015-02-10

325

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

PubMed Central

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

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

2013-01-01

326

Contribution of Six Flagellin Genes to the Flagellum Biogenesis of Vibrio vulnificus and In Vivo Invasion  

PubMed Central

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

Kim, Soo Young; Thanh, Xuan Tran Thi; Jeong, Kwangjoon; Kim, Seong Bin; Pan, Sang O; Jung, Che Hun; Hong, Seol Hee

2014-01-01

327

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

PubMed Central

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

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

2012-01-01

328

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

PubMed Central

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

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

2014-01-01

329

Determining Vaccination Frequency in Farmed Rainbow Trout Using Vibrio anguillarum O1 Specific Serum Antibody Measurements  

PubMed Central

Background Despite vaccination with a commercial vaccine with a documented protective effect against Vibrio anguillarum O1 disease outbreaks caused by this bacterium have been registered among rainbow trout at Danish fish farms. The present study examined specific serum antibody levels as a valid marker for assessing vaccination status in a fish population. For this purpose a highly sensitive enzyme-linked immunosorbent assay (ELISA) was developed and used to evaluate sera from farmed rainbow trout vaccinated against V. anguillarum O1. Study Design Immune sera from rainbow trout immunised with an experimental vaccine based on inactivated V. anguillarum O1 bacterin in Freund’s incomplete adjuvant were used for ELISA optimisation. Subsequently, sera from farmed rainbow trout vaccinated with a commercial vaccine against V. anguillarum were analysed with the ELISA. The measured serum antibody levels were compared with the vaccine status of the fish (vaccinated/unvaccinated) as evaluated through visual examination. Results Repeated immunisation with the experimental vaccine lead to increasing levels of specific serum antibodies in the vaccinated rainbow trout. The farmed rainbow trout responded with high antibody levels to a single injection with the commercial vaccine. However, the diversity in responses was more pronounced in the farmed fish. Primary visual examinations for vaccine status in rainbow trout from the commercial farm revealed a large pool of unvaccinated specimens (vaccination failure rate?=?20%) among the otherwise vaccinated fish. Through serum analyses using the ELISA in a blinded set-up it was possible to separate samples collected from the farmed rainbow trout into vaccinated and unvaccinated fish. Conclusions Much attention has been devoted to development of new and more effective vaccines. Here we present a case from a Danish rainbow trout farm indicating that attention should also be directed to the vaccination procedure in order to secure high vaccination frequencies necessary for optimal protection with a reported effective vaccine. PMID:23185402

Holten-Andersen, Lars; Dalsgaard, Inger; Nylén, Jørgen; Lorenzen, Niels; Buchmann, Kurt

2012-01-01

330

Understanding the Role of Host Hemocytes in a Squid/Vibrio Symbiosis Using Transcriptomics and Proteomics  

PubMed Central

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 host’s 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

Collins, Andrew J.; Schleicher, Tyler R.; Rader, Bethany A.; Nyholm, Spencer V.

2012-01-01

331

Detection of Salmonella bacterium in drinking water using microring resonator.  

PubMed

A new microring resonator system is proposed for the detection of the Salmonella bacterium in drinking water, which is made up of SiO2-TiO2 waveguide embedded inside thin film layer of the flagellin. The change in refractive index due to the binding of the Salmonella bacterium with flagellin layer causes a shift in the output signal wavelength and the variation in through and drop port's intensities, which leads to the detection of Salmonella bacterium in drinking water. The sensitivity of proposed sensor for detecting of Salmonella bacterium in water solution is 149 nm/RIU and the limit of detection is 7 × 10(- 4)RIU. PMID:25133457

Bahadoran, Mahdi; Noorden, Ahmad Fakhrurrazi Ahmad; Mohajer, Faeze Sadat; Abd Mubin, Mohamad Helmi; Chaudhary, Kashif; Jalil, Muhammad Arif; Ali, Jalil; Yupapin, Preecha

2014-08-18

332

Phosphoenolpyruvate carboxykinase from the moderate halophile Vibrio costicola. Purification, physicochemical properties and the effect of univalent-cation salts.  

PubMed

Phosphoenolpyruvate carboxykinase (PEPCK) was purified to homogeneity from the moderately halophilic bacterium Vibrio costicola. The enzyme is monomeric, with an Mr of 62,000, as determined by the Svedberg equation, by using values of s0(20,w) 4.4 x 10(-13) s, D20,w 6.13 x 10(-7) cm2.s-1 and v 0.719 cm3.g-1. Compared with other, non-halophilic, PEPCKs, the enzyme from V. costicola had a significantly lower total content of hydrophobic amino acids. The contents of glycine and serine were higher in the V. costicola enzyme (16.7 and 10.22% respectively) than in the non-halophilic PEPCKs (6.8-9.6% and 4.67-6.28% respectively). These results resemble those obtained by De Médicis & Rossignol [(1979) Experientia 35, 1546-1547] with the pyruvate kinase from V. costicola, and agree with the proposal by Lanyi [(1974) Bacteriol. Rev. 38, 272-290] of partial replacement of hydrophobic amino acids by glycine and serine to maintain the balance between hydrophobic and hydrophilic forces in halophilic enzymes. In agreement with this 'halophilic' characteristic, the PEPCK was somewhat stabilized by 1 M-KCl or -NaCl and by 20% (v/v) glycerol, and its oxaloacetate-decarboxylation and 14CO2-oxaloacetate-exchange reactions were activated by KCl and NaCl up to 1 M, whereas the fixation of CO2 on PEP had a maximum at 0.025-0.05 M salt. These facts suggest that the salts, at concentrations probably physiological for the bacterium, increase the formation of the complex of oxaloacetate and ATP with the enzyme, and the liberation of the products, PEP and ADP, thus favouring PEP synthesis. PMID:2775185

Salvarrey, M S; Cannata, J J; Cazzulo, J J

1989-05-15

333

Genome-Wide SNP-Genotyping Array to Study the Evolution of the Human Pathogen Vibrio vulnificus Biotype 3  

PubMed Central

Vibrio vulnificus is an aquatic bacterium and an important human pathogen. Strains of V. vulnificus are classified into three different biotypes. The newly emerged biotype 3 has been found to be clonal and restricted to Israel. In the family Vibrionaceae, horizontal gene transfer is the main mechanism responsible for the emergence of new pathogen groups. To better understand the evolution of the bacterium, and in particular to trace the evolution of biotype 3, we performed genome-wide SNP genotyping of 254 clinical and environmental V. vulnificus isolates with worldwide distribution recovered over a 30-year period, representing all phylogeny groups. A custom single-nucleotide polymorphism (SNP) array implemented on the Illumina GoldenGate platform was developed based on 570 SNPs randomly distributed throughout the genome. In general, the genotyping results divided the V. vulnificus species into three main phylogenetic lineages and an additional subgroup, clade B, consisting of environmental and clinical isolates from Israel. Data analysis suggested that 69% of biotype 3 SNPs are similar to SNPs from clade B, indicating that biotype 3 and clade B have a common ancestor. The rest of the biotype 3 SNPs were scattered along the biotype 3 genome, probably representing multiple chromosomal segments that may have been horizontally inserted into the clade B recipient core genome from other phylogroups or bacterial species sharing the same ecological niche. Results emphasize the continuous evolution of V. vulnificus and support the emergence of new pathogenic groups within this species as a recurrent phenomenon. Our findings contribute to a broader understanding of the evolution of this human pathogen. PMID:25526263

Hayman, Ryan B.; Bar-On, Yudi; Linetsky, Alex; Shmoish, Michael; Sanjuán, Eva; Amaro, Carmen; Walt, David R.; Kashi, Yechezkel

2014-01-01

334

VibrioBase: a model for next-generation genome and annotation database development.  

PubMed

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

Choo, Siew Woh; Heydari, Hamed; Tan, Tze King; Siow, Cheuk Chuen; Beh, Ching Yew; Wee, Wei Yee; Mutha, Naresh V R; Wong, Guat Jah; Ang, Mia Yang; Yazdi, Amir Hessam

2014-01-01

335

High Prevalence of Vibrio cholerae Non-O1 Carrying Heat-Stable-Enterotoxin-Encoding Genes among Vibrio Isolates from a Temperate-Climate River Basin of Central Italy  

PubMed Central

Vibrio spp. of clinical interest from the Arno River basin (Tuscany, Italy) were investigated in this study. Vibrios were isolated from 70% of water samples. Vibrio cholerae non-O1 was the most prevalent species (82% of isolates), followed by Vibrio mimicus (10%) and Vibrio metschnikovii (8%). Recovery of vibrios was correlated with temperature, pH, and various indicators of municipal pollution. None of the 150 Vibrio isolates carried ctx-related genomic sequences, whereas 18 (14.6%) of the 123 V. cholerae non-O1 isolates and 1 (6.7%) of the 15 V. mimicus isolates carried sto alleles. These findings indicate that considerable circulation of sto-positive vibrios may occur in temperate-climate freshwater environments. PMID:16535661

Caldini, G.; Neri, A.; Cresti, S.; Boddi, V.; Rossolini, G. M.; Lanciotti, E.

1997-01-01

336

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

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

Valeru, Soni Priya; Shanan, Salah; Alossimi, Haifa; Sandström, Gunnar

2014-01-01

337

Vibrio vulnificus sepsis in solid organ transplantation: a medical nemesis.  

PubMed

We report two cases of Vibrio vulnificus wound infection leading to fulminant sepsis syndrome in immunocompromised solid organ transplant recipients. Features of clinical presentation in each of these cases suggest that host immune factors are of great importance in the virulence of this organism and that immunocompromised recipients of solid organ transplants are particularly vulnerable to life-threatening consequences from infection with Vibrio vulnificus. Prompt institution of antibiotic therapy and early consideration for surgical wound debridement are the mainstay of successful management. Heart and other organ transplant recipients should be educated and warned about the hazards associated with raw oysters and shellfish consumption and asked to exercise caution when exposed to a salt water environment. PMID:7654744

Ali, A; Mehra, M R; Stapleton, D D; Kemmerly, S A; Ramireddy, K; Smart, F W; Augustine, S; Ventura, H O

1995-01-01

338

Comparison of methods for the rapid recognition of cholera vibrios  

PubMed Central

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

Finkelstein, Richard A.; Gomez, Cecilia Z.

1963-01-01

339

A quorum sensing-disrupting brominated thiophenone with a promising therapeutic potential to treat luminescent vibriosis.  

PubMed

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

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

2012-01-01

340

Cytotoxic Cell Vacuolating Activity from Vibrio cholerae Hemolysin  

Microsoft Academic Search

A Vibrio cholerae cytotoxin, designated VcVac, was found to cause vacuolation in Vero cells. It was originally detected in the pathogenic O1 Amazonia variant of V. cholerae and later shown to be produced in environmental strains and some El Tor strains. Comparison of VcVac production in various strains suggested that hemolysin was responsible for the vacuolating phenotype. Genetic experiments established

ANA COELHO; JOAO R. C. ANDRADE; ANA CAROLINA P. VICENTE; VICTOR J. DIRITA

2000-01-01

341

Highly Potent, Chemically Stable Quorum Sensing Agonists for Vibrio Cholerae.  

PubMed

In the Vibrio cholerae pathogen, initiation of bacterial quorum sensing pathways serves to suppress virulence. We describe herein a potent and chemically stable small molecule agonist of V. cholerae quorum sensing, which was identified through rational drug design based on the native quorum sensing signal. This novel agonist may serve as a useful lead compound for the control of virulence in V. cholerae. PMID:24436778

Perez, Lark J; Karagounis, Theodora K; Hurley, Amanda; Bassler, Bonnie L; Semmelhack, Martin F

2014-01-01

342

Photodynamic Antimicrobial Chemotherapy in Aquaculture: Photoinactivation Studies of Vibrio fischeri  

Microsoft Academic Search

BackgroundPhotodynamic antimicrobial chemotherapy (PACT) combines light, a light-absorbing molecule that initiates a photochemical or photophysical reaction, and oxygen. The combined action of these three components originates reactive oxygen species that lead to microorganisms' destruction. The aim was to evaluate the efficiency of PACT on Vibrio fischeri: 1) with buffer solution, varying temperature, pH, salinity and oxygen concentration values; 2) with

Eliana Alves; Maria A. F. Faustino; João P. C. Tomé; Maria G. P. M. S. Neves; Augusto C. Tomé; José A. S. Cavaleiro; Ângela Cunha; Newton C. M. Gomes; Adelaide Almeida

2011-01-01

343

Wind Direction and Its Linkage with Vibrio cholerae Dissemination  

PubMed Central

Background The relevance of climatic events as causative factors for cholera epidemics is well known. However, examinations of the involvement of climatic factors in intracontinental disease distribution are still absent. Objectives The spreading of cholera epidemics may be related to the dominant wind direction over land. Methods We examined the geographic diffusion of three cholera outbreaks through their linkage with the wind direction: a) the progress of Vibrio cholerae O1 biotype El Tor in Africa during 1970–1971 and b) again in 2005–2006; and c) the rapid spread of Vibrio cholerae O139 over India during 1992–1993. We also discuss the possible influence of the wind direction on windborn dissemination by flying insects, which may serve as vectors. Results Analysis of air pressure data at sea level and at several altitudes over Africa, India, and Bangladesh show a correspondence between the dominant wind direction and the intracontinental spread of cholera. Conclusions We explored the hypothesis that winds have assisted the progress of cholera Vibrios throughout continents. The current analysis supports the hypothesis that aeroplankton (the tiny life forms that float in the air and that may be caught and carried upward by the wind, landing far from their origin) carry the cholera bacteria from one body of water to an adjacent one. This finding may improve our understanding of how climatic factors are involved in the rapid distribution of new strains throughout a vast continental area. Awareness of the aerial transfer of Vibrio cholerae may assist health authorities by improving the prediction of the disease’s geographic dissemination. PMID:17384764

Paz, Shlomit; Broza, Meir

2007-01-01

344

Evaluation of methods for enumeration of Vibrio parahaemolyticus from seafood.  

PubMed Central

The efficiency of several enrichment broths in recovering Vibrio parahaemolyticus inoculated into fish homogenates was studied. Recovery by the most probable number technique was very low in all the broths, while direct plating on thiosulfate citrate bile salt sucrose agar yielded better recovery. A decrease in the enrichment time to 8 from 18 h did not improve recovery. At concentrations exceeding 2.5 micrograms/ml, polymyxin was inhibitory to V. parahaemolyticus. PMID:3767361

Karunasagar, I; Venugopal, M N; Karunasagar, I; Segar, K

1986-01-01

345

The Winnowing: Establishing the Squid-Vibrio Symbiosis  

NSDL National Science Digital Library

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

Nyholm, Spencer V.; Mcfall-Ngai, Margaret; Microbiology, Nature R.

346

Association of Vibrio cholerae with fresh water amoebae  

Microsoft Academic Search

Summary. An investigation was undertaken to determine whether Acanthamoeba polyphaga SHI and Naegleria gruberi 1518\\/le could affect the survival of various strains of Vibrio cholerae in laboratory microcosms. In microcosms pre-inoculated with trophozoites of amoebae, all six strains of V. choZerae tested survived and multiplied during 24 h. In control microcosms without trophozoites of amoebae, survival of the V. cholerae

SUSAN THOM; D. WARHURSTt; B. S. Drasar

1992-01-01

347

Predicting the ecotoxicity of ionic liquids towards Vibrio fischeri using genetic function approximation and least squares support vector machine.  

PubMed

Ionic liquids (ILs) are widely used in industrial production for their unique physicochemical properties, and they are even regarded as green solvents. However, the recent study showed ILs might pose a potential risk to aquatic ecosystems. In the present work, the quantitative structure-activity relationship (QSAR) models, including genetic function approximation (GFA) and least squares support vector machine (LSSVM) were developed for predicting the ecotoxicity of ILs towards the marine bacterium Vibrio fischeri based on the descriptors calculated from cations and anions. Five descriptors were selected by GFA and used to develop the linear model. From the discussion of descriptors, the cation structure was the main factor to the toxicity, which mainly depended on the size, lipophilic, and 3D molecular structure of cations. In order to capture the nonlinear nature, the LSSVM model was also built for more accurately predicting the ecotoxicity. The GFA and LSSVM models were performed the rigorous internal and external validation, further verifying these models with excellent robustness and predictive ability. Therefore, both of models can be used for the prediction of the ecotoxicity of newly synthesized and untested ILs, and can provide reference information and theoretical guidance for designing and synthesizing safer and more eco-friendly ILs. PMID:25464300

Ma, Shuying; Lv, Min; Deng, Fangfang; Zhang, Xiaoyun; Zhai, Honglin; Lv, Wenjuan

2015-02-11

348

A Vibrio cholerae protease needed for killing of Caenorhabditis elegans has a role in protection from natural predator grazing  

PubMed Central

Vibrio cholerae is the causal bacterium of the diarrheal disease cholera, and its growth and survival are thought to be curtailed by bacteriovorous predators, e.g., ciliates and flagellates. We explored Caenorhabditis elegans as a test organism after finding that V. cholerae can cause lethal infection of this nematode. By reverse genetics we identified an extracellular protease, the previously uncharacterized PrtV protein, as being necessary for killing. The killing effect is associated with the colonization of bacteria within the Caenorhabditis elegans intestine. We also show that PrtV is essential for V. cholerae in the bacterial survival from grazing by the flagellate Cafeteria roenbergensis and the ciliate Tetrahymena pyriformis. The PrtV protein appears to have an indirect role in the interaction of V. cholerae with mammalian host cells as judged from tests with tight monolayers of human intestinal epithelial cells. Our results demonstrate a key role for PrtV in V. cholerae interaction with grazing predators, and we establish Caenorhabditis elegans as a convenient organism for identification of V. cholerae factors involved in host interactions and environmental persistence. PMID:16754867

Vaitkevicius, Karolis; Lindmark, Barbro; Ou, Gangwei; Song, Tianyan; Toma, Claudia; Iwanaga, Masaaki; Zhu, Jun; Andersson, Agneta; Hammarström, Marie-Louise; Tuck, Simon; Wai, Sun Nyunt

2006-01-01

349

Application of the VPp1 bacteriophage combined with a coupled enzyme system in the rapid detection of Vibrio parahaemolyticus.  

PubMed

For rapid and quantitative detection of Vibrio parahaemolyticus, a method combining the specific lysis of bacteriophages with a bacterial luciferase-flavin mononucleotide:nicotinamide adenine dinucleotide oxidoreductase bioluminescent system in vitro was developed. A V. parahaemolyticus detection system was established by optimizing three main influencing factors: bacteriophage titer, volume ratio of the bacteriophage to its host bacterium, and lysis time. A standard curve between the number of bacteria and the luminescence intensity of the coupled enzyme system was studied and revealed a good linear relationship. More than 10(7)colony-forming units (cfu)·ml(-1) bacteria in pure culture and >10(8) cfu·ml(-1) bacteria in oyster samples were readily detected without pre-enrichment. Furthermore, >10(0) cfu·ml(-1) bacteria in oyster samples were readily detected after 4h of enrichment culture. Because of its rapid detection, high specificity, and simplicity in operation, this method is an effective tool for detecting living bacteria in food and environmental samples. PMID:24440165

Peng, Yong; Jin, Yanqiu; Lin, Hong; Wang, Jingxue; Khan, Muhammad Naseem

2014-03-01

350

In situ strain-level detection and identification of Vibrio parahaemolyticus using surface-enhanced Raman spectroscopy.  

PubMed

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

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

351

Solar-photocatalytic disinfection of Vibrio cholerae by using Ag@ZnO core-shell structure nanocomposites.  

PubMed

Disinfection of Gram-negative bacterium Vibrio cholerae 569B in aqueous matrix by solar-photocatalysis mediated by Ag@ZnO core-shell structure nanocomposite particles was investigated. Silver nanoparticles are synthesized by the reduction of silver perchlorate followed by precipitation of zinc oxide shell and are employed in the photocatalytic disinfection of the model pathogen. Effect of photocatalyst loading and reaction temperature on the disinfection kinetics was studied. Disinfection efficiency in laboratory as well as real water samples was compared with that of pure-ZnO and TiO2 (Degussa P25). Nanocomposite system has shown optimum disinfection (?98%) at 40-60min of sun-light exposure with a catalyst loading of 0.5mg/L of the reaction solution. The reduction of aquatic bacterial densities by photocatalytically active Ag@ZnO core-shell nanocomposite in presence of natural sun-light may have potential ex situ application in water decontamination at ambient conditions. PMID:25523714

Das, Sourav; Sinha, Sayantan; Suar, Mrutyunjay; Yun, Soon-Il; Mishra, Amrita; Tripathy, Suraj K

2015-01-01

352

Changes in membrane fatty acid composition during entry of Vibrio vulnificus into the viable but nonculturable state.  

PubMed

Vibrio vulnificus, a Gram-negative bacterium found in estuarine waters, is responsible for over 95% of all seafood-related deaths in the United States. As a result of a temperature downshift to 5 degrees C, this organism enters the viable but nonculturable (VBNC) state. Changes in the membrane fatty acid (FA) composition of V. vulnificus may be a contributing factor to the ability of this organism to enter into and survive in the VBNC state. This hypothesis was tested by incubating the organism at 5 degrees C in artificial sea water and analyzing the cells' FAs during the initial hours of temperature and nutrient down-shift. Prior to downshift, the predominant FAs were 16:0, 16:1 and 18:0. During the first four hours of downshift, statistically significant changes occurred in 15:0, 16:1, 16:0, 17:0, and 18:0. These results indicate that changes in FA composition occur prior to entry of V. vulnificus into the VBNC state, suggesting that the ability to maintain membrane fluidity may be a factor in this physiological response. Cells in which fatty acid synthesis was inhibited did not survive, indicating that active fatty acid metabolism is essential for entry of cells into the VBNC state. PMID:15357297

Day, Ashley P; Oliver, James D

2004-06-01

353

Toxicological responses of the hard clam Meretrix meretrix exposed to excess dissolved iron or challenged by Vibrio parahaemolyticus.  

PubMed

The responses of genes encoding defense components such as ferritin, the lipopolysaccharide-induced tumor necrosis factor-alpha factor (LITAF), the inhibitor of nuclear factor-?B (I?B), metallothionein, and glutathione peroxidase were assessed at the transcriptional level in order to investigate the toxicological and immune mechanism of the hard clam Meretrix meretrix (HCMM) following challenge with iron or a bacterium (Vibrio parahaemolyticus). Fe dissolved in natural seawater led to an increase of Fe content in both the hepatopancreas and gill tissue of HCMM between 4 and 15 days of exposure. The ferritin gene responded both transcriptionally as indicated by real-time quantitative PCR and translationally as shown by western blotting results to iron exposure and both transcriptional and translational ferritin expression in the hepatopancreas had a positive correlation with the concentration of dissolved iron in seawater. Both iron and V. parahaemolyticus exposure triggered immune responses with similar trends in clam tissues. There was a significant post-challenge mRNA expression of LITAF and I?B at 3h, ferritin at 24h, and metallothionein and glutathione peroxidase at 48h. This behavior might be linked to their specific functions in physiological processes. These results suggested that similar signaling pathways were triggered during both iron and V. parahaemolyticus challenges. Here, we indicated that the ferritin of Meretrix meretrix was an intermediate in the pathway of iron homeostasis and in its innate immune defense mechanism. PMID:25269138

Zhou, Qing; Zhang, Yong; Peng, Hui-Fang; Ke, Cai-Huan; Huang, He-Qing

2014-11-01

354

Activity of Alkyl Hydroperoxide Reductase Subunit C1 and C2 of Vibrio parahaemolyticus against Different Peroxides.  

PubMed

Alkylhydroperoxide reductase subunit C (ahpC) gene functions were characterized in Vibrio parahaemolyticus, a commonly occurring marine foodborne enteropathogenic bacterium. Two ahpC genes, ahpC1 (VPA1683) and ahpC2 (VP0580), encoded putative 2-cysteine peroxiredoxins, which are highly similar to the homologous proteins of V. vulnificus. The responses of deletion mutants of ahpC genes to various peroxides were compared with and without gene complementation and at different incubation temperatures. The growth of the ahpC1 and ahpC12 double mutants in liquid medium was significantly inhibited by organic peroxides, cumene hydroperoxide and tert-butyl hydroperoxide. However, inhibition was higher at 12°C and 22°C then at 37°C. Inhibiting effects were prevented by the complementary ahpC1 gene. Inconsistent detoxification of H2O2 by ahpC genes was demonstrated in an agar medium but not in a liquid medium. Complementation with an ahpC2 gene partially restored the peroxidase effect in the double ahpC12 mutant at 22°C. This investigation reveals that ahpC1 is the chief peroxidase gene that acts against organic peroxides in V. parahaemolyticus and that the function of the ahpC genes is influenced by incubation temperature. PMID:25239899

Chung, Chun-Hui; Ma, Tsung-Yong; Fen, Shin-Yuan; Wong, Hin-Chung

2014-09-19

355

The Vibrio cholerae quorum-sensing autoinducer CAI-1: analysis of the biosynthetic enzyme CqsA  

SciTech Connect

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.

Kelly, R.; Bolitho, M; Higgins, D; Lu, W; Ng, W; Jeffrey, P; Rabinowitz, J; Semmelhack, M; Hughson, F; Bassler, B

2009-01-01

356

Generation and Characterization of a scFv Antibody Against T3SS Needle of Vibrio parahaemolyticus.  

PubMed

Vibrio parahaemolyticus, a halophilic gram-negative bacterium, is a food-borne pathogen that largely inhabits marine and estuarine environments, and poses a serious threat to human and animal health all over the world. The hollow "needle" channel, a specific assemble of T3SS which exists in most of gram-negative bacteria, plays a key role in the transition of virulence effectors to host cells. In this study, needle protein VP1694 was successfully expressed and purified, and the fusion protein Trx-VP1694 was used to immunize Balb/c mice. Subsequently, a phage single-chain fragment variable antibody (scFv) library was constructed, and a specific scFv against VP1694 named scFv-FA7 was screened by phage display panning. To further identify the characters of scFv, the soluble expression vector pACYC-scFv-skp was constructed and the soluble scFv was purified by Ni(2+) affinity chromatography. ELISA analysis showed that the scFv-FA7 was specific to VP1694 antigen, and its affinity constant was 1.07 × 10(8 )L/mol. These results offer a molecular basis to prevent and cure diseases by scFv, and also provide a new strategy for further research on virulence mechanism of T3SS in V. parahaemolyticus by scFv. PMID:25320414

Wang, Rongzhi; Fang, Sui; Xiang, Shuangshuang; Ling, Sumei; Yuan, Jun; Wang, Shihua

2014-06-01

357

Vibrio anguillarum colonization of rainbow trout integument requires a DNA locus involved in exopolysaccharide transport and biosynthesis.  

PubMed

Vibrio anguillarum, part of the normal flora of the aquatic milieu, causes a fatal haemorrhagic septicaemia in marine fish. In this study, a rainbow trout model was used to characterize the colonization of fish skin by V. anguillarum. Within 5 h after infection, the bacterium penetrated the skin mucosal layer, attached to the scales within 12 h, and formed a biofilm by 24-48 h. Two divergently transcribed putative operons, orf1-wbfD-wbfC-wbfB and wza-wzb-wzc, were shown to play a role in skin colonization and virulence. The first operon encodes proteins of unknown function. The wza-wzb-wzc genes encode a secretin, tyrosine kinase and tyrosine phosphatase, respectively, which are similar to proteins in polysaccharide transport complexes. Compared with the wild type, polar mutations in wza, orf1 and wbfD caused a decrease in exopolysaccharide biosynthesis but not lipopolysaccharide biosynthesis. The wza and orf1 mutants did not attach to fish scales; whereas, the wbfD mutant had a wild-type phenotype. Moreover, the wza and orf1 mutants had decreased exoprotease activity, in particular the extracellular metalloprotease EmpA, as well as mucinase activity suggesting that these mutations also affect exoenzyme secretion. Thus, the exopolysaccharide transport system in V. anguillarum is required for attachment to fish skin, possibly preventing mechanical removal of bacteria via natural sloughing of mucus. PMID:17222135

Croxatto, Antony; Lauritz, Johan; Chen, Chang; Milton, Debra L

2007-02-01

358

Genetic analysis of the capsule polysaccharide (K antigen) and exopolysaccharide genes in pandemic Vibrio parahaemolyticus O3:K6  

Microsoft Academic Search

BACKGROUND: Pandemic Vibrio parahaemolyticus has undergone rapid changes in both K- and O-antigens, making detection of outbreaks more difficult. In order to understand these rapid changes, the genetic regions encoding these antigens must be examined. In Vibrio cholerae and Vibrio vulnificus, both O-antigen and capsular polysaccharides are encoded in a single region on the large chromosome; a similar arrangement in

Yuansha Chen; Jianli Dai; J Glenn Morris; Judith A Johnson

2010-01-01

359

Effect of Temperature on Growth of Vibrio paraphemolyticus and Vibrio vulnificus in Flounder, Salmon Sashimi and Oyster Meat  

PubMed Central

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

Kim, Yoo Won; Lee, Soon Ho; Hwang, In Gun; Yoon, Ki Sun

2012-01-01

360

Temperature effects on the depuration of Vibrio parahaemolyticus and Vibrio vulnificus from the American oyster (Crassostrea virginica).  

PubMed

This study investigated temperature effects on depuration for reducing Vibrio parahaemolyticus and Vibrio vulnificus in American oyster (Crassostrea virginica). Raw oysters were inoculated with 5-strain cocktail of V. parahaemolyticus or V. vulnificus to levels of 10(4) to 10(5) MPN (most probable number)/g and depurated in artificial seawater (ASW) at 22, 15, 10, and 5 degrees C. Depuration of oysters at 22 degrees C had limited effects on reducing V. parahaemolyticus or V. vulnificus in the oysters. Populations of V. parahaemolyticus and V. vulnificus were reduced by 1.2 and 2.0 log MPN/g, respectively, after 48 h of depuration at 22 degrees C. Decreasing water temperature to 15 degrees C increased the efficacy of depuration in reducing V. parahaemolyticus and V. vulnificus in oysters. Reductions of V. parahaemolyticus and V. vulnificus in oysters increased to 2.1 and 2.9 log MPN/g, respectively, after 48 h of depuration at 15 degrees C. However, depurations at 10 and 5 degrees C were less effective than at 15 degrees C in reducing the Vibrio spp. in oysters. Extended depuration at 15 degrees C for 96 h increased reductions of V. parahaemolyticus and V. vulnificus in oysters to 2.6 and 3.3 log MPN/g, respectively. PMID:19323759

Chae, M J; Cheney, D; Su, Y-C

2009-03-01

361

Agrobacterium tumefaciens is a diazotrophic bacterium  

SciTech Connect

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.

Kanvinde, L.; Sastry, G.R.K. (Univ. of Leeds (England))

1990-07-01

362

Evaluating the use of fatty acid profiles to identify deep-sea Vibrio isolates  

Microsoft Academic Search

Capillary gas chromatography with flame ionisation detection (GC-FID) was used to determine the cellular fatty acid (CFA) profiles of a number of Vibrio strains obtained from ATCC and grown on various media. This initial determination for optimal growth conditions, including type of medium and incubation temperature, for these various ATCC Vibrio species, was important for use in the subsequent evaluation

Maria Hoffmann; Markus Fischer; Paul Whittaker

2010-01-01

363

Indole Acts as an Extracellular Cue Regulating Gene Expression in Vibrio cholerae  

Microsoft Academic Search

Indole has been proposed to act as an extracellular signal molecule influencing biofilm formation in a range of bacteria. For this study, the role of indole in Vibrio cholerae biofilm formation was examined. It was shown that indole activates genes involved in vibrio polysaccharide (VPS) production, which is essential for V. cholerae biofilm formation. In addition to activating these genes,

Ryan S. Mueller; Sinem Beyhan; Simran G. Saini; Fitnat H. Yildiz; Douglas H. Bartlett

2009-01-01

364

Draft Genome Sequence of Vibrio fortis Dalian14 Isolated from Diseased Sea Urchin (Strongylocentrotus intermedius)  

PubMed Central

Here, we report the draft genome sequence of Vibrio fortis Dalian14 isolated from diseased sea urchin (Strongylocentrotus intermedius) during disease outbreaks in North China. The availability of this genome sequence will facilitate the study of the mechanisms of pathogenicity and evolution of Vibrio species. PMID:24994792

Ding, Jun; Dou, Yan; Wang, Yinan

2014-01-01

365

Vibrio fischeri exhibit the growth advantage in stationary-phase Branden Petrun and C. Phoebe Lostroh  

E-print Network

and C. Phoebe Lostroh Abstract: Vibrio fischeri are bioluminescent marine bacteria that can be isolated stationnaire (GASP), phase stationnaire a` long terme. Vibrio fischeri are bioluminescent marine bacteria high during the night, when the squid use bacterial bioluminescence as a counter-predation strategy

McFall-Ngai, Margaret

366

CHITINASE DETERMINANTS OF 'VIBRIO VULNIFICUS': GENE CLONING AND APPLICATIONS OF A CHITINASE PROBE  

EPA Science Inventory

To initiate study of the genetic control of chitinolytic activity in vibrios, the chitobiase gene was isolated by cloning chromosomal DNA prepared from Vibrio vulnificus. Chimeric plasmids were constructed from Sau3A I partial digests of chromosomal DNA by ligating 5 to 15-Kiloba...

367

Reactogenicity of live-attenuated Vibrio cholerae vaccines is dependent on flagellins  

E-print Network

vaccine strains have led to side effects in volunteers. Such side effects, often referred to as vaccineReactogenicity of live-attenuated Vibrio cholerae vaccines is dependent on flagellins Haopeng Ruia disease caused by the motile Gram- negative rod Vibrio cholerae. Live-attenuated V. cholerae vaccines

Mekalanos, John

368

A SIMPLE FLUOROGENIC METHOD TO ASSESS VIBRIO CHOLERAE AND AEROMONAS HYDROPHILA IN WELL WATER  

Technology Transfer Automated Retrieval System (TEKTRAN)

We present the colony overlay procedure for peptidases (COPP), a simple, fluorogenic assay for the rapid detection of Vibrio cholerae and Aeromonas hydrophila in fresh well water. Substrate cleavage by enzymes present in Vibrio and Aeromonas species produces fluorescent foci on UV-light irradiated ...

369

Whole-Genome Sequence of Quorum-Sensing Vibrio tubiashii Strain T33.  

PubMed

Vibrio tubiashii strain T33 was isolated from the coastal waters of Morib, Malaysia, and was shown to possess quorum-sensing activity similar to that of its famous relative Vibrio fischeri. Here, the assembly and annotation of its genome are presented. PMID:25555738

Izzati Mohamad, Nur; Yin, Wai-Fong; Chan, Kok-Gan

2015-01-01

370

Cell Host & Microbe A Type III Secretion System in Vibrio cholerae  

E-print Network

Cell Host & Microbe Article A Type III Secretion System in Vibrio cholerae Translocates a Formin.03.005 SUMMARY We have previously characterized a non-O1, non-O139 Vibrio cholerae strain, AM-19226, that lacks mouse model. We also identified VopF, which is conserved among T3SS-positive V. cholerae strains

Mekalanos, John

371

Cochleates Derived from Vibrio cholerae O1 Proteoliposomes: The Impact of Structure  

E-print Network

Cochleates Derived from Vibrio cholerae O1 Proteoliposomes: The Impact of Structure Transformation formation. In this study, proteoliposomes from V. cholerae O1 (PLc) (sized 160.761.6 nm) were transformed´rez O, Zayas C, Pe´rez JL, Callico´ A, et al. (2012) Cochleates Derived from Vibrio cholerae O1

Strathclyde, University of

372

Conformation of the Hexasaccharide Repeating Subunit from the Vibrio cholerae O139 Capsular Polysaccharide  

E-print Network

Conformation of the Hexasaccharide Repeating Subunit from the Vibrio cholerae O139 Capsular ReceiVed February 5, 2003 ABSTRACT: In the past decade, several outbreaks of cholera have been reported to be caused by Vibrio cholerae O139, a strain which differs from the more common O1 strain in that the former

Bush, C. Allen

373

DNA Damage and Reactive Nitrogen Species are Barriers to Vibrio cholerae Colonization of the Infant Mouse  

E-print Network

DNA Damage and Reactive Nitrogen Species are Barriers to Vibrio cholerae Colonization of the Infant Vibrio cholerae pass through the stomach and colonize the small intestines of its host. Here, we show that V. cholerae requires at least two types of DNA repair systems to efficiently compete

Mekalanos, John

374

A defined transposon mutant library and its use in identifying motility genes in Vibrio cholerae  

E-print Network

A defined transposon mutant library and its use in identifying motility genes in Vibrio cholerae D of interest. Here, we present a near-saturating transposon insertion library in Vibrio cholerae strain C6706, a clinical isolate belonging to the O1 El Tor biotype responsible for the current cholera pandemic. Automated

Mekalanos, John

375

Survival of Vibrio cholerae in Nutrient-Poor Environments Is Associated with a Novel ``Persister''  

E-print Network

Survival of Vibrio cholerae in Nutrient-Poor Environments Is Associated with a Novel ``Persister to a ``persister'' phenotype. Although toxigenic Vibrio cholerae, responsible for the disease cholera, can be found. cholerae into a nutrient-poor filter sterilized lake water (FSLW) microcosm promoted a shift to what we

Ali, Afsar

376

Insights into Vibrio cholerae Intestinal Colonization from Monitoring Fluorescently Labeled Bacteria  

E-print Network

Insights into Vibrio cholerae Intestinal Colonization from Monitoring Fluorescently Labeled, Massachusetts, United States of America Abstract Vibrio cholerae, the agent of cholera, is a motile non. cholerae intestinal colonization is derived from enumeration of wt and mutant V. cholerae recovered from

von Andrian, Ulrich H.

377

Whole-Genome Sequence of Quorum-Sensing Vibrio tubiashii Strain T33  

PubMed Central

Vibrio tubiashii strain T33 was isolated from the coastal waters of Morib, Malaysia, and was shown to possess quorum-sensing activity similar to that of its famous relative Vibrio fischeri. Here, the assembly and annotation of its genome are presented. PMID:25555738

Izzati Mohamad, Nur; Yin, Wai-Fong

2015-01-01

378

A Tetrodotoxin-Producing Vibrio Strain, LM1, from the Puffer Fish Fugu vermicularis radiatus  

Microsoft Academic Search

identified as members of the genus Vibrio (21). Also, Simidu et al. (29) demonstrated that many species of marine bacteria, including Vibrio spp. (21), Pseudomonas spp. (33), and actino- mycetes (1), produce TTX. Three individual F. vermicularis radiatus puffer fish (male; body weight, 45 g) were collected at Pusan, Korea, in March 1998, transported live to the laboratory, and maintained

MYOUNG-JA LEE; DONG-YOUN JEONG; WOO-SEONG KIM; HYUN-DAE KIM; CHEORL-HO KIM; WON-WHAN PARK; YONG-HA PARK; KYUNG-SAM KIM; HYUNG-MIN KIM; DONG-SOO KIM

2000-01-01

379

Structural characteristics of alkaline phosphatase from the moderately halophilic bacterium Halomonas sp. 593  

PubMed Central

Alkaline phosphatase (AP) from the moderate halophilic bacterium Halomonas sp. 593 (HaAP) catalyzes the hydrolysis of phosphomonoesters over a wide salt-concentration range (1–4?M NaCl). In order to clarify the structural basis of its halophilic characteristics and its wide-range adaptation to salt concentration, the tertiary structure of HaAP was determined by X-ray crystallography to 2.1?Å resolution. The unit cell of HaAP contained one dimer unit corresponding to the biological unit. The monomer structure of HaAP contains a domain comprised of an 11-stranded ?-sheet core with 19 surrounding ?-helices similar to those of APs from other species, and a unique ‘crown’ domain containing an extended ‘arm’ structure that participates in formation of a hydrophobic cluster at the entrance to the substrate-binding site. The HaAP structure also displays a unique distribution of negatively charged residues and hydrophobic residues in comparison to other known AP structures. AP from Vibrio sp. G15-21 (VAP; a slight halophile) has the highest similarity in sequence (70.0% identity) and structure (C? r.m.s.d. of 0.82?Å for the monomer) to HaAP. The surface of the HaAP dimer is substantially more acidic than that of the VAP dimer (144 exposed Asp/Glu residues versus 114, respectively), and thus may enable the solubility of HaAP under high-salt conditions. Conversely, the monomer unit of HaAP formed a substantially larger hydrophobic interior comprising 329 C atoms from completely buried residues, whereas that of VAP comprised 264 C atoms, which may maintain the stability of HaAP under low-salt conditions. These characteristics of HaAP may be responsible for its unique functional adaptation permitting activity over a wide range of salt concentrations. PMID:24598750

Arai, Shigeki; Yonezawa, Yasushi; Ishibashi, Matsujiro; Matsumoto, Fumiko; Adachi, Motoyasu; Tamada, Taro; Tokunaga, Hiroko; Blaber, Michael; Tokunaga, Masao; Kuroki, Ryota

2014-01-01

380

A novel eliminase from a marine bacterium that degrades hyaluronan and chondroitin sulfate.  

PubMed

Lyases cleave glycosaminoglycans (GAGs) in an eliminative mechanism and are important tools for the structural analysis and oligosaccharide preparation of GAGs. Various GAG lyases have been identified from terrestrial but not marine organisms even though marine animals are rich in GAGs with unique structures and functions. Herein we isolated a novel GAG lyase for the first time from the marine bacterium Vibrio sp. FC509 and then recombinantly expressed and characterized it. It showed strong lyase activity toward hyaluronan (HA) and chondroitin sulfate (CS) and was designated as HA and CS lyase (HCLase). It exhibited the highest activities to both substrates at pH 8.0 and 0.5 m NaCl at 30 °C. Its activity toward HA was less sensitive to pH than its CS lyase activity. As with most other marine enzymes, HCLase is a halophilic enzyme and very stable at temperatures from 0 to 40 °C for up to 24 h, but its activity is independent of divalent metal ions. The specific activity of HCLase against HA and CS reached a markedly high level of hundreds of thousands units/mg of protein under optimum conditions. The HCLase-resistant tetrasaccharide ?(4,5)HexUA?1-3GalNAc(6-O-sulfate)?1-4GlcUA(2-O-sulfate)?1-3GalNAc(6-O-sulfate) was isolated from CS-D, the structure of which indicated that HCLase could not cleave the galactosaminidic linkage bound to 2-O-sulfated d-glucuronic acid (GlcUA) in CS chains. Site-directed mutagenesis indicated that HCLase may work via a catalytic mechanism in which Tyr-His acts as the Brønsted base and acid. Thus, the identification of HCLase provides a useful tool for HA- and CS-related research and applications. PMID:25122756

Han, Wenjun; Wang, Wenshuang; Zhao, Mei; Sugahara, Kazuyuki; Li, Fuchuan

2014-10-01

381

Structural characteristics of alkaline phosphatase from the moderately halophilic bacterium Halomonas sp. 593.  

PubMed

Alkaline phosphatase (AP) from the moderate halophilic bacterium Halomonas sp. 593 (HaAP) catalyzes the hydrolysis of phosphomonoesters over a wide salt-concentration range (1-4?M NaCl). In order to clarify the structural basis of its halophilic characteristics and its wide-range adaptation to salt concentration, the tertiary structure of HaAP was determined by X-ray crystallography to 2.1?Å resolution. The unit cell of HaAP contained one dimer unit corresponding to the biological unit. The monomer structure of HaAP contains a domain comprised of an 11-stranded ?-sheet core with 19 surrounding ?-helices similar to those of APs from other species, and a unique `crown' domain containing an extended `arm' structure that participates in formation of a hydrophobic cluster at the entrance to the substrate-binding site. The HaAP structure also displays a unique distribution of negatively charged residues and hydrophobic residues in comparison to other known AP structures. AP from Vibrio sp. G15-21 (VAP; a slight halophile) has the highest similarity in sequence (70.0% identity) and structure (C(?) r.m.s.d. of 0.82?Å for the monomer) to HaAP. The surface of the HaAP dimer is substantially more acidic than that of the VAP dimer (144 exposed Asp/Glu residues versus 114, respectively), and thus may enable the solubility of HaAP under high-salt conditions. Conversely, the monomer unit of HaAP formed a substantially larger hydrophobic interior comprising 329 C atoms from completely buried residues, whereas that of VAP comprised 264 C atoms, which may maintain the stability of HaAP under low-salt conditions. These characteristics of HaAP may be responsible for its unique functional adaptation permitting activity over a wide range of salt concentrations. PMID:24598750

Arai, Shigeki; Yonezawa, Yasushi; Ishibashi, Matsujiro; Matsumoto, Fumiko; Adachi, Motoyasu; Tamada, Taro; Tokunaga, Hiroko; Blaber, Michael; Tokunaga, Masao; Kuroki, Ryota

2014-03-01

382

Vibrio Pathogenicity Island and Cholera Toxin Genetic Element-Associated Virulence Genes and Their Expression in Non-O1 Non-O139 Strains of Vibrio cholerae  

Microsoft Academic Search

A non-O1 non-O139 Vibrio cholerae strain, 10259, belonging to the serogroup O53 was shown to harbor genes related to the vibrio pathogenicity island (VPI) and a cholera toxin (CT) genetic element called CTX. While the nucleotide sequence of the strain 10259 tcpA gene differed significantly (26 and 28%) from those of O1 classical and El Tor biotype strains, respectively, partial

Amit Sarkar; Ranjan K. Nandy; G. Balakrish Nair; Asoke C. Ghose

2002-01-01

383

VibrioBase: A MALDI-TOF MS database for fast identification of Vibrio spp. that are potentially pathogenic in humans.  

PubMed

Mesophilic marine bacteria of the family Vibrionaceae, specifically V. cholerae, V. parahaemolyticus and V. vulnificus, are considered to cause severe illness in humans. Due to climate-change-driven temperature increases, higher Vibrio abundances and infections are predicted for Northern Europe, which in turn necessitates environmental surveillance programs to evaluate this risk. We propose that whole-cell matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) profiling is a promising tool for the fast and reliable species classification of environmental isolates. Because the reference database does not contain sufficient Vibrio spectra we generated the VibrioBase database in this study. Mass spectrometric data were generated from 997 largely environmental strains and filed in this new database. MALDI-TOF MS clusters were assigned based on the species classification obtained by analysis of partial rpoB (RNA polymerase beta-subunit) sequences. The affiliation of strains to species-specific clusters was consistent in 97% of all cases using both approaches, and the extended VibrioBase generated more specific species identifications with higher matching scores compared to the commercially available database. Therefore, we have made the VibrioBase database freely accessible, which paves the way for detailed risk assessment studies of potentially pathogenic Vibrio spp. from marine environments. PMID:25466918

Erler, René; Wichels, Antje; Heinemeyer, Ernst-August; Hauk, Gerhard; Hippelein, Martin; Reyes, Nadja Torres; Gerdts, Gunnar

2014-11-01

384

Molecular analysis of the emergence of pandemic Vibrio parahaemolyticus  

PubMed Central

Background Vibrio parahaemolyticus is abundant in the aquatic environment particularly in warmer waters and is the leading cause of seafood borne gastroenteritis worldwide. Prior to 1995, numerous V. parahaemolyticus serogroups were associated with disease, however, in that year an O3:K6 serogroup emerged in Southeast Asia causing large outbreaks and rapid hospitalizations. This new highly virulent strain is now globally disseminated. Results We performed a four-way BLAST analysis on the genome sequence of V. parahaemolyticus RIMD2210633, an O3:K6 isolate from Japan recovered in 1996, versus the genomes of four published Vibrio species and constructed genome BLAST atlases. We identified 24 regions, gaps in the genome atlas, of greater than 10 kb that were unique to RIMD2210633. These 24 regions included an integron, f237 phage, 2 type III secretion systems (T3SS), a type VI secretion system (T6SS) and 7 Vibrio parahaemolyticus genomic islands (VPaI-1 to VPaI-7). Comparative genomic analysis of our fifth genome, V. parahaemolyticus AQ3810, an O3:K6 isolate recovered in 1983, identified four regions unique to each V. parahaemolyticus strain. Interestingly, AQ3810 did not encode 8 of the 24 regions unique to RMID, including a T6SS, which suggests an additional virulence mechanism in RIMD2210633. The distribution of only the VPaI regions was highly variable among a collection of 42 isolates and phylogenetic analysis of these isolates show that these regions are confined to a pathogenic clade. Conclusion Our data show that there is considerable genomic flux in this species and that the new highly virulent clone arose from an O3:K6 isolate that acquired at least seven novel regions, which included both a T3SS and a T6SS. PMID:18590559

Boyd, E Fidelma; Cohen, Ana Luisa V; Naughton, Lynn M; Ussery, David W; Binnewies, Tim T; Stine, O Colin; Parent, Michelle A

2008-01-01

385

Evaluation of bactericidal activity of weakly acidic electrolyzed water (WAEW) against Vibrio vulnificus and Vibrio parahaemolyticus.  

PubMed

Vibrio parahaemolyticus and Vibriovulnificus cause severe foodborne illness in humans; thus, to reduce outbreaks of disease, it is clearly important to reduce food contamination by these pathogens. Although electrolyzed oxidizing (EO) water has been reported to exhibit strong bactericidal activities against many pathogens, it has never been tested against V. vulnificus and V. parahaemolyticus. The purpose of this study was to evaluate the bactericidal activity of weakly acidic electrolyzed water (WAEW), a type of EO water, against V. vulnificus and V. parahaemolyticus. Cell suspensions and cell cultures of both pathogens were treated for 30s with sodium hypochlorite solution containing 35mg/L available chlorine concentration (ACC) or WAEW containing 35mg/L ACC. After an initial inoculum of 5.7logCFU/mL, the number of viable V. vulnificus cells was reduced by 2.2 logs after treatment for 60s with sodium hypochlorite solution containing 35mg/L ACC, while no cells survived treatment with WAEW for 30s. Similar results were obtained for V. parahaemolyticus. Under open storage conditions, WAEW maintained bactericidal activities against cell suspensions of both strains after 5weeks but disappeared against cell cultures of the two strains after 5weeks. Under closed storage conditions, however, WAEW maintained bactericidal activities against both cell suspensions and cell cultures of each strain after 5weeks. No cells were detected in the cell suspensions and cultures when the ACC of WAEW was more than 20mg/L and treatment time was greater than 15s. Bactericidal activity of WAEW against V. vulnificus cell culture was reduced when the ACC of WAEW was less than 15mg/L but was maintained in the V. vulnificus cell suspension when the ACC of WAEW was 0.5mg/L. Thus, the bactericidal activity of WAEW was primarily affected by ACC rather than treatment time. Similar results were obtained for V. parahaemolyticus, indicating that WAEW kills these microorganisms more quickly than a chemical product such as sodium hypochlorite (NaClO), even at equivalent ACCs. PMID:20004034

Quan, Yaru; Choi, Kyoo-Duck; Chung, Donghwa; Shin, Il-Shik

2010-01-01

386

Genome Sequence of Dehalobacter UNSWDHB, a Chloroform-Dechlorinating Bacterium  

PubMed Central

The chloroform-respiring bacterium Dehalobacter UNSWDHB was isolated from subsurface soil contaminated with a mixture of organohalides, including chloroform. Here, we present its 3.2-Mb genome. PMID:24051315

Deshpande, Nandan P.; Wong, Yie K.; Manefield, Mike; Wilkins, Marc R.

2013-01-01

387

Rhodoferax ferrireducens sp. nov., a psychrotolerant, facultatively anaerobic bacterium  

E-print Network

Rhodoferax ferrireducens sp. nov., a psychrotolerant, facultatively anaerobic bacterium ferrireducens sp. nov. INTRODUCTION Fe(III) is often an abundant electron acceptor for microbial respiration other forms of respiration. However, it is becoming increasingly apparent that there is a wide

Lovley, Derek

388

THE ETIOLOGICAL RELATION OF SPIRILLA (VIBRIO FETUS) TO BOVINE ABORTION  

PubMed Central

The isolation in pure culture of a definite morphological entity (vibrio or spirillum) with practically the same biological characters from a series of cases of the same clinical complex (abortion) establishes a presumption in favor of the specific identity of the organisms and also in favor of the inference that such organisms are etiologically related to the diseased condition. This presumption is strengthened by the fact that disease of the fetal membranes followed the injection of pure cultures of this organism in two out of four cases. PMID:19868361

Smith, Theobald

1919-01-01

389

Optimal enrichment time for isolation of Vibrio parahaemolyticus from seafood.  

PubMed

The growth of Vibrio parahaemolyticus in a liquid medium was compared with that of human fecal flora and estuarine flora. No marked differences were noted between growth at 25 and 37 degrees C for V. parahaemolyticus. However, the marine organisms were strongly inhibited when incubated at 37 degrees C. Incubation for 8 h in an enrichment broth yielded V. parahaemolyticus growth, even with a small inoculum, whereas the marine and fecal floras were inhibited. Therefore, enrichment for 8 h at 37 degrees C appears to be optimal for isolation of V. parahaemolyticus, permitting more rapid results in seafood analysis. PMID:6651300

Dupray, E; Cormier, M

1983-11-01

390

Optimal enrichment time for isolation of Vibrio parahaemolyticus from seafood.  

PubMed Central

The growth of Vibrio parahaemolyticus in a liquid medium was compared with that of human fecal flora and estuarine flora. No marked differences were noted between growth at 25 and 37 degrees C for V. parahaemolyticus. However, the marine organisms were strongly inhibited when incubated at 37 degrees C. Incubation for 8 h in an enrichment broth yielded V. parahaemolyticus growth, even with a small inoculum, whereas the marine and fecal floras were inhibited. Therefore, enrichment for 8 h at 37 degrees C appears to be optimal for isolation of V. parahaemolyticus, permitting more rapid results in seafood analysis. PMID:6651300

Dupray, E; Cormier, M

1983-01-01

391

Characterization of a halophilic heterotrophic nitrification-aerobic denitrification bacterium and its application on treatment of saline wastewater.  

PubMed

A novel halophilic bacterium capable of heterotrophic nitrification-aerobic denitrification was isolated from marine sediments and identified as Vibrio diabolicus SF16. It had ability to remove 91.82% of NH4(+)-N (119.77mg/L) and 99.71% of NO3(-)-N (136.43mg/L). The nitrogen balance showed that 35.83% of initial NH4(+)-N (119.77mg/L) was changed to intracellular nitrogen, and 53.98% of the initial NH4(+)-N was converted to gaseous denitrification products. The existence of napA gene further proved the aerobic denitrification ability of strain SF16. The optimum culture conditions were salinity 1-5%, sodium acetate as carbon source, C/N 10, and pH 7.5-9.5. When an aerated biological filter system inoculated with strain SF16 was employed to treat saline wastewater, the average removal efficiency of NH4(+)-N and TN reached 97.14% and 73.92%, respectively, indicating great potential of strain SF16 for future full-scale applications. PMID:25557251

Duan, Jinming; Fang, Hongda; Su, Bing; Chen, Jinfang; Lin, Jinmei

2015-03-01

392

Cholera outbreaks (2012) in three districts of Nepal reveal clonal transmission of multi-drug resistant Vibrio cholerae O1  

PubMed Central

Background Although endemic cholera causes significant morbidity and mortality each year in Nepal, lack of information about the causal bacterium often hinders cholera intervention and prevention. In 2012, diarrheal outbreaks affected three districts of Nepal with confirmed cases of mortality. This study was designed to understand the drug response patterns, source, and transmission of Vibrio cholerae associated with 2012 cholera outbreaks in Nepal. Methods V. cholerae (n?=?28) isolated from 2012 diarrhea outbreaks {n?=?22; Kathmandu (n?=?12), Doti (n?=?9), Bajhang (n?=?1)}, and surface water (n?=?6; Kathmandu) were tested for antimicrobial response. Virulence properties and DNA fingerprinting of the strains were determined by multi-locus genetic screening employing polymerase chain reaction, DNA sequencing, and pulsed-field gel electrophoresis (PFGE). Results All V. cholerae strains isolated from patients and surface water were confirmed to be toxigenic, belonging to serogroup O1, Ogawa serotype, biotype El Tor, and possessed classical biotype cholera toxin (CTX). Double-mismatch amplification mutation assay (DMAMA)-PCR revealed the V. cholerae strains to possess the B-7 allele of ctx subunit B. DNA sequencing of tcpA revealed a point mutation at amino acid position 64 (N???S) while the ctxAB promoter revealed four copies of the tandem heptamer repeat sequence 5'-TTTTGAT-3'. V. cholerae possessed all the ORFs of the Vibrio seventh pandemic island (VSP)-I but lacked the ORFs 498–511 of VSP-II. All strains were multidrug resistant with resistance to trimethoprim-sulfamethoxazole (SXT), nalidixic acid (NA), and streptomycin (S); all carried the SXT genetic element. DNA sequencing and deduced amino acid sequence of gyrA and parC of the NAR strains (n?=?4) revealed point mutations at amino acid positions 83 (S???I), and 85 (S???L), respectively. Similar PFGE (NotI) pattern revealed the Nepalese V. cholerae to be clonal, and related closely with V. cholerae associated with cholera in Bangladesh and Haiti. Conclusions In 2012, diarrhea outbreaks in three districts of Nepal were due to transmission of multidrug resistant V. cholerae El Tor possessing cholera toxin (ctx) B-7 allele, which is clonal and related closely with V. cholerae associated with cholera in Bangladesh and Haiti. PMID:25022982

2014-01-01

393

New insights into Oculina patagonica coral diseases and their associated Vibrio spp. communities.  

PubMed

Bleaching of Oculina patagonica has been extensively studied in the Eastern Mediterranean Sea, although no studies have been carried out in the Western basin. In 1996 Vibrio mediterranei was reported as the causative agent of bleaching in O. patagonica but it has not been related to bleached or healthy corals since 2003, suggesting that it was no longer involved in bleaching of O. patagonica. In an attempt to clarify the relationship between Vibrio spp., seawater temperature and coral diseases, as well as to investigate the putative differences between Eastern and Western Mediterranean basins, we have analysed the seasonal patterns of the culturable Vibrio spp. assemblages associated with healthy and diseased O. patagonica colonies. Two sampling points located in the Spanish Mediterranean coast were chosen for this study: Alicante Harbour and the Marine Reserve of Tabarca. A complex and dynamic assemblage of Vibrio spp. was present in O. patagonica along the whole year and under different environmental conditions and coral health status. While some Vibrio spp. were detected all year around in corals, the known pathogens V. mediteranei and V. coralliilyticus were only present in diseased specimens. The pathogenic potential of these bacteria was studied by experimental infection under laboratory conditions. Both vibrios caused diseased signs from 24?°C, being higher and faster at 28?°C. Unexpectedly, the co-inoculation of these two Vibrio species seemed to have a synergistic pathogenic effect over O. patagonica, as disease signs were readily observed at temperatures at which bleaching is not normally observed. PMID:24621525

Rubio-Portillo, Esther; Yarza, Pablo; Peñalver, Cindy; Ramos-Esplá, Alfonso A; Antón, Josefa

2014-09-01

394

Persistence, seasonal dynamics and pathogenic potential of Vibrio communities from Pacific oyster hemolymph.  

PubMed

Bacteria of the genus Vibrio occur at a continuum from free-living to symbiotic life forms, including opportunists and pathogens, that can contribute to severe diseases, for instance summer mortality events of Pacific oysters Crassostrea gigas. While most studies focused on Vibrio isolated from moribund oysters during mortality outbreaks, investigations of the Vibrio community in healthy oysters are rare. Therefore, we characterized the persistence, diversity, seasonal dynamics, and pathogenicity of the Vibrio community isolated from healthy Pacific oysters. In a reciprocal transplant experiment we repeatedly sampled hemolymph from adult Pacific oysters to differentiate population from site-specific effects during six months of in situ incubation in the field. We characterized virulence phenotypes and genomic diversity based on multilocus sequence typing in a total of 70 Vibrio strains. Based on controlled infection experiments we could show that strains with the ability to colonize healthy adult oysters can also have the potential to induce high mortality rates on larvae. Diversity and abundance of Vibrio varied significantly over time with highest values during and after spawning season. Vibrio communities from transplanted and stationary oysters converged over time, indicating that communities were not population specific, but rather assemble from the surrounding environment forming communities, some of which can persist over longer periods. PMID:24728233

Wendling, Carolin C; Batista, Frederico M; Wegner, K Mathias

2014-01-01

395

The human pathogenic vibrios--a public health update with environmental perspectives.  

PubMed Central

Pathogenic Vibrio species are naturally-occurring bacteria in freshwater and saline aquatic environments. Counts of free-living bacteria in water are generally less than required to induce disease. Increases in number of organisms towards an infective dose can occur as water temperatures rise seasonally followed by growth and concentration of bacteria on higher animals, such as chitinous plankton, or accumulation by shellfish and seafood. Pathogenic Vibrio species must elaborate a series of virulence factors to elicit disease in humans. Activities which predispose diarrhoeal and extraintestinal infections include ingestion of seafood and shellfish and occupational or recreational exposure to natural aquatic environments, especially those above 20 degrees C. Travel to areas endemic for diseases due to pathogenic Vibrio species may be associated with infections. Host risk factors strongly associated with infections are lack of gastric acid and liver disorders. Involvement of pathogenic Vibrio species in cases of diarrhoea should be suspected especially if infection is associated with ingestion of seafood or shellfish, raw or undercooked, in the previous 72 h. Vibrio species should be suspected in any acute infection associated with wounds sustained or exposed in the marine or estuarine environment. Laboratories serving coastal areas where infection due to pathogenic Vibrio species are most likely to occur should consider routine use of TCBS agar and other detection regimens for culture of Vibrio species from faeces, blood and samples from wound and ear infections. PMID:2673820

West, P. A.

1989-01-01

396

Persistence, Seasonal Dynamics and Pathogenic Potential of Vibrio Communities from Pacific Oyster Hemolymph  

PubMed Central

Bacteria of the genus Vibrio occur at a continuum from free-living to symbiotic life forms, including opportunists and pathogens, that can contribute to severe diseases, for instance summer mortality events of Pacific oysters Crassostrea gigas. While most studies focused on Vibrio isolated from moribund oysters during mortality outbreaks, investigations of the Vibrio community in healthy oysters are rare. Therefore, we characterized the persistence, diversity, seasonal dynamics, and pathogenicity of the Vibrio community isolated from healthy Pacific oysters. In a reciprocal transplant experiment we repeatedly sampled hemolymph from adult Pacific oysters to differentiate population from site-specific effects during six months of in situ incubation in the field. We characterized virulence phenotypes and genomic diversity based on multilocus sequence typing in a total of 70 Vibrio strains. Based on controlled infection experiments we could show that strains with the ability to colonize healthy adult oysters can also have the potential to induce high mortality rates on larvae. Diversity and abundance of Vibrio varied significantly over time with highest values during and after spawning season. Vibrio communities from transplanted and stationary oysters converged over time, indicating that communities were not population specific, but rather assemble from the surrounding environment forming communities, some of which can persist over longer periods. PMID:24728233

Wendling, Carolin C.; Batista, Frederico M.; Wegner, K. Mathias

2014-01-01

397

Cellulase activity of a haloalkaliphilic anaerobic bacterium, strain Z-7026  

Microsoft Academic Search

Summary  The cellulolytic activity of an alkaliphilic obligate anaerobic bacterium, Z-7026, which was isolated from the microbial community of soda-lake sediments and belongs to the cluster III of Clostridia with low G+C content, was studied. The bacterium was capable of growing in media with cellulose or cellobiose as the sole energy sources. Its maximal growth rate on cellobiose (0.042–0.046 h–1) was observed

E. A. Zvereva; T. V. Fedorova; V. V. Kevbrin; T. N. Zhilina; M. L. Rabinovich

2006-01-01

398

Taxonomic characterization of the cellulose-degrading bacterium NCIB 10462  

SciTech Connect

The gram negative cellulase-producing bacterium NCIB 10462 has been previously named Pseudomonas fluorescens subsp. or var. cellulosa. Since there is renewed interest in cellulose-degrading bacteria for use in bioconversion of cellulose to chemical feed stocks and fuels, we re-examined the characteristics of this microorganism to determine its proper taxonomic characterization and to further define it`s true metabolic potential. Metabolic and physical characterization of NCIB 10462 revealed that this was an alkalophilic, non-fermentative, gram negative, oxidase positive, motile, cellulose-degrading bacterium. The aerobic substrate utilization profile of this bacterium was found to have few characteristics consistent with a classification of P. fluorescens with a very low probability match with the genus Sphingomonas. Total lipid analysis did not reveal that any sphingolipid bases are produced by this bacterium. NCIB 10462 was found to grow best aerobically but also grows well in complex media under reducing conditions. NCIB 10462 grew slowly under full anaerobic conditions on complex media but growth on cellulosic media was found only under aerobic conditions. Total fatty acid analysis (MIDI) of NCIB 10462 failed to group this bacterium with a known pseudomonas species. However, fatty acid analysis of the bacteria when grown at temperatures below 37{degrees}C suggest that the organism is a pseudomonad. Since a predominant characteristic of this bacterium is it`s ability to degrade cellulose, we suggest it be called Pseudomonas cellulosa.

Dees, C.; Ringleberg, D.; Scott, T.C. [Oak Ridge National Lab., TN (United States); Phelps, T. [Univ. of Tennessee, Knoxville, TN (United States)

1994-06-01

399

Molecular and biochemical characterization of an extracellular serine-protease from Vibrio metschnikovii J1.  

PubMed

A protease-producing bacterium was isolated from an alkaline wastewater of the soap industry and identified as Vibrio metschnikovii J1 on the basis of the 16S rRNA gene sequencing and biochemical properties. The strain was found to over-produce proteases when it was grown at 30 degrees C in media containing casein as carbon source (14,000 U ml(-1)). J1 enzyme, the major protease produced by V. metschnikovii J1, was purified by a three-step procedure, with a 2.1-fold increase in specific activity and 33.3% recovery. The molecular weight of the purified protease was estimated to be 30 kDa by SDS-PAGE and gel filtration. The N-terminal amino acid sequence of the first 20 amino acids of the purified J1 protease was AQQTPYGIRMVQADQLSDVY. The enzyme was highly active over a wide range of pH from 9.0 to 12.0, with an optimum at pH 11.0. The optimum temperature for the purified enzyme was 60 degrees C. The activity of the enzyme was totally lost in the presence of PMSF, suggesting that the purified enzyme is a serine protease. The kinetic constants K (m) and K (cat) of the purified enzyme using N-succinyl-L-Ala-L-Ala-L-Pro-L-Phe-p-nitroanilide were 0.158 mM and 1.14 x 10(5) min(-1), respectively. The catalytic efficiency (K (cat) /K (m)) was 7.23 x 10(8) min(-1) M(-1). The enzyme showed extreme stability toward non-ionic surfactants and oxidizing agents. In addition, it showed high stability and compatibility with some commercial liquid and solid detergents. The aprJ1 gene, which encodes the alkaline protease from V. metschnikovii J1, was isolated, and its DNA sequence was determined. The deduced amino acid sequence of the preproenzyme differs from that of V. metschnikovii RH530 detergent-stable protease by 12 amino acids, 7 located in the propeptide and 5 in the mature enzyme. PMID:19390884

Jellouli, Kemel; Bougatef, Ali; Manni, Laila; Agrebi, Rym; Siala, Rayda; Younes, Islem; Nasri, Moncef

2009-07-01

400

LitR is a repressor of syp genes and has a temperature-sensitive regulatory effect on biofilm formation and colony morphology in vibrio (Aliivibrio) salmonicida.  

PubMed

Vibrio (Aliivibrio) salmonicida is the etiological agent of cold water vibriosis, a disease in farmed Atlantic salmon (Salmo salar) that is kept under control due to an effective vaccine. A seawater temperature below 12°C is normally required for disease development. Quorum sensing (QS) is a cell density-regulated communication system that bacteria use to coordinate activities involved in colonization and pathogenesis, and we have previously shown that inactivation of the QS master regulator LitR attenuates the V. salmonicida strain LFI1238 in a fish model. We show here that strain LFI1238 and a panel of naturally occurring V. salmonicida strains are poor biofilm producers. Inactivation of litR in the LFI1238 strain enhances medium- and temperature-dependent adhesion, rugose colony morphology, and biofilm formation. Chemical treatment and electron microscopy of the biofilm identified an extracellular matrix consisting mainly of a fibrous network, proteins, and polysaccharides. Further, by microarray analysis of planktonic and biofilm cells, we identified a number of genes regulated by LitR and, among these, were homologues of the Vibrio fischeri symbiosis polysaccharide (syp) genes. The syp genes were regulated by LitR in both planktonic and biofilm lifestyle analyses. Disruption of syp genes in the V. salmonicida ?litR mutant alleviated adhesion, rugose colony morphology, and biofilm formation. Hence, LitR is a repressor of syp transcription that is necessary for expression of the phenotypes examined. The regulatory effect of LitR on colony morphology and biofilm formation is temperature sensitive and weak or absent at temperatures above the bacterium's upper threshold for pathogenicity. PMID:24973072

Hansen, Hilde; Bjelland, Ane Mohn; Ronessen, Maria; Robertsen, Espen; Willassen, Nils Peder

2014-09-01

401

LitR Is a Repressor of syp Genes and Has a Temperature-Sensitive Regulatory Effect on Biofilm Formation and Colony Morphology in Vibrio (Aliivibrio) salmonicida  

PubMed Central

Vibrio (Aliivibrio) salmonicida is the etiological agent of cold water vibriosis, a disease in farmed Atlantic salmon (Salmo salar) that is kept under control due to an effective vaccine. A seawater temperature below 12°C is normally required for disease development. Quorum sensing (QS) is a cell density-regulated communication system that bacteria use to coordinate activities involved in colonization and pathogenesis, and we have previously shown that inactivation of the QS master regulator LitR attenuates the V. salmonicida strain LFI1238 in a fish model. We show here that strain LFI1238 and a panel of naturally occurring V. salmonicida strains are poor biofilm producers. Inactivation of litR in the LFI1238 strain enhances medium- and temperature-dependent adhesion, rugose colony morphology, and biofilm formation. Chemical treatment and electron microscopy of the biofilm identified an extracellular matrix consisting mainly of a fibrous network, proteins, and polysaccharides. Further, by microarray analysis of planktonic and biofilm cells, we identified a number of genes regulated by LitR and, among these, were homologues of the Vibrio fischeri symbiosis polysaccharide (syp) genes. The syp genes were regulated by LitR in both planktonic and biofilm lifestyle analyses. Disruption of syp genes in the V. salmonicida ?litR mutant alleviated adhesion, rugose colony morphology, and biofilm formation. Hence, LitR is a repressor of syp transcription that is necessary for expression of the phenotypes examined. The regulatory effect of LitR on colony morphology and biofilm formation is temperature sensitive and weak or absent at temperatures above the bacterium's upper threshold for pathogenicity. PMID:24973072

Bjelland, Ane Mohn; Ronessen, Maria; Robertsen, Espen; Willassen, Nils Peder

2014-01-01

402

Insight into the assembly mechanism in the supramolecular rings of the sodium-driven Vibrio flagellar motor from the structure of FlgT  

PubMed Central

Flagellar motility is a key factor for bacterial survival and growth in fluctuating environments. The polar flagellum of a marine bacterium, Vibrio alginolyticus, is driven by sodium ion influx and rotates approximately six times faster than the proton-driven motor of Escherichia coli. The basal body of the sodium motor has two unique ring structures, the T ring and the H ring. These structures are essential for proper assembly of the stator unit into the basal body and to stabilize the motor. FlgT, which is a flagellar protein specific for Vibrio sp., is required to form and stabilize both ring structures. Here, we report the crystal structure of FlgT at 2.0-Å resolution. FlgT is composed of three domains, the N-terminal domain (FlgT-N), the middle domain (FlgT-M), and the C-terminal domain (FlgT-C). FlgT-M is similar to the N-terminal domain of TolB, and FlgT-C resembles the N-terminal domain of FliI and the ?/? subunits of F1-ATPase. To elucidate the role of each domain, we prepared domain deletion mutants of FlgT and analyzed their effects on the basal-body ring formation. The results suggest that FlgT-N contributes to the construction of the H-ring structure, and FlgT-M mediates the T-ring association on the LP ring. FlgT-C is not essential but stabilizes the H-ring structure. On the basis of these results, we propose an assembly mechanism for the basal-body rings and the stator units of the sodium-driven flagellar motor. PMID:23530206

Terashima, Hiroyuki; Li, Na; Sakuma, Mayuko; Koike, Masafumi; Kojima, Seiji; Homma, Michio; Imada, Katsumi

2013-01-01

403

Influence of Alginate on Attachment of Vibrio spp. to Stainless Steel Surfaces in Seawater  

PubMed Central

The influence of alginate on the attachment of Vibrio alginolyticus and Vibrio pelagius biovar II to stainless steel was investigated. When the bacteria were in stationary phase, alginate decreased the number of attached bacteria in the case of each Vibrio sp. In contrast, when V. pelagius biovar II was grown on alginate and harvested in log phase, attachment was increased. This effect may be due to nutrient availability at the surface or to receptors on the bacterial surface which interact with alginate adsorbed to the metal. PMID:16347345

Gordon, Andrew S.

1987-01-01

404

Vibrio cholerae non-O1 infection in cirrhotics: case report and literature review.  

PubMed

Vibrio species are ubiquitous in the marine environment and can cause severe infections in cirrhotic patients. Patients with liver disease should be warned about the potential dangers of consuming raw or undercooked seafood, and avoiding exposure of wounds to seawater. We report a case of severe sepsis from Vibrio cholerae non-O1 in a patient with cirrhosis awaiting orthotopic liver transplant. This case is aimed to advise clinicians about the importance of V. cholerae subtypes, and non-cholera Vibrio species infections in cirrhotic patients, highlighting the need to educate these patients to stay away from undercooked seafood. PMID:18811633

Patel, N M; Wong, M; Little, E; Ramos, A X; Kolli, G; Fox, K M; Melvin, J; Moore, A; Manch, R

2009-02-01

405

Antimicrobial Susceptibility of Vibrio vulnificus and Vibrio parahaemolyticus Recovered from Recreational and Commercial Areas of Chesapeake Bay and Maryland Coastal Bays  

PubMed Central

Vibrio vulnificus and V. parahaemolyticus in the estuarine-marine environment are of human health significance and may be increasing in pathogenicity and abundance. Vibrio illness originating from dermal contact with Vibrio laden waters or through ingestion of seafood originating from such waters can cause deleterious health effects, particularly if the strains involved are resistant to clinically important antibiotics. The purpose of this study was to evaluate antimicrobial susceptibility among these pathogens. Surface-water samples were collected from three sites of recreational and commercial importance from July to September 2009. Samples were plated onto species-specific media and resulting V. vulnificus and V. parahaemolyticus strains were confirmed using polymerase chain reaction assays and tested for antimicrobial susceptibility using the Sensititre® microbroth dilution system. Descriptive statistics, Friedman two-way Analysis of Variance (ANOVA) and Kruskal-Wallis one-way ANOVA were used to analyze the data. Vibrio vulnificus (n?=?120) and V. parahaemolyticus (n?=?77) were isolated from all sampling sites. Most isolates were susceptible to antibiotics recommended for treating Vibrio infections, although the majority of isolates expressed intermediate resistance to chloramphenicol (78% of V. vulnificus, 96% of V. parahaemolyticus). Vibrio parahaemolyticus also demonstrated resistance to penicillin (68%). Sampling location or month did not significantly impact V. parahaemolyticus resistance patterns, but V. vulnificus isolates from St. Martin's River had lower overall intermediate resistance than that of the other two sampling sites during the month of July (p?=?0.0166). Antibiotics recommended to treat adult Vibrio infections were effective in suppressing bacterial growth, while some antibiotics recommended for pediatric treatment were not effective against some of the recovered isolates. To our knowledge, these are the first antimicrobial susceptibility data of V. vulnificus and V. parahaemolyticus recovered from the Chesapeake Bay. These data can serve as a baseline against which future studies can be compared to evaluate whether susceptibilities change over time. PMID:24586914

Shaw, Kristi S.; Rosenberg Goldstein, Rachel E.; He, Xin; Jacobs, John M.; Crump, Byron C.; Sapkota, Amy R.

2014-01-01

406

Vibrio cholerae Represses Polysaccharide Synthesis To Promote Motility in Mucosa.  

PubMed

The viscoelastic mucus layer of gastrointestinal tracts is a host defense barrier that a successful enteric pathogen, such as Vibrio cholerae, must circumvent. V. cholerae, the causative agent of cholera, is able to penetrate the mucosa and colonize the epithelial surface of the small intestine. In this study, we found that mucin, the major component of mucus, promoted V. cholerae movement on semisolid medium and in liquid medium. A genome-wide screen revealed that Vibrio polysaccharide (VPS) production was inversely correlated with mucin-enhanced motility. Mucin adhesion assays indicated that VPS bound to mucin. Moreover, we found that vps expression was reduced upon exposure to mucin. In an infant mouse colonization model, mutants that overexpressed VPS colonized less effectively than wild-type strains in more distal intestinal regions. These results suggest that V. cholerae is able to sense mucosal signals and modulate vps expression accordingly so as to promote fast motion in mucus, thus allowing for rapid spread throughout the intestines. PMID:25561707

Liu, Zhenyu; Wang, Yuning; Liu, Shengyan; Sheng, Ying; Rueggeberg, Karl-Gustav; Wang, Hui; Li, Jie; Gu, Frank X; Zhong, Zengtao; Kan, Biao; Zhu, Jun

2015-03-01

407

Invariant recognition of polychromatic images of Vibrio cholerae 01  

NASA Astrophysics Data System (ADS)

Cholera is an acute intestinal infectious disease. It has claimed many lives throughout history, and it continues to be a global health threat. Cholera is considered one of the most important emergence diseases due its relation with global climate changes. Automated methods such as optical systems represent a new trend to make more accurate measurements of the presence and quantity of this microorganism in its natural environment. Automatic systems eliminate observer bias and reduce the analysis time. We evaluate the utility of coherent optical systems with invariant correlation for the recognition of Vibrio cholerae O1. Images of scenes are recorded with a CCD camera and decomposed in three RGB channels. A numeric simulation is developed to identify the bacteria in the different samples through an invariant correlation technique. There is no variation when we repeat the correlation and the variation between images correlation is minimum. The position-, scale-, and rotation-invariant recognition is made with a scale transform through the Mellin transform. The algorithm to recognize Vibrio cholerae O1 is the presence of correlation peaks in the green channel output and their absence in red and blue channels. The discrimination criterion is the presence of correlation peaks in red, green, and blue channels.

Alvarez-Borrego, Josue; Mourino-Perez, Rosa R.; Cristobal, Gabriel; Pech-Pacheco, Jose L.

2002-04-01

408

Recombination Shapes the Structure of an Environmental Vibrio cholerae Population ? †  

PubMed Central

Vibrio cholerae consists of pathogenic strains that cause sporadic gastrointestinal illness or epidemic cholera disease and nonpathogenic strains that grow and persist in coastal aquatic ecosystems. Previous studies of disease-causing strains have shown V. cholerae to be a primarily clonal bacterial species, but isolates analyzed have been strongly biased toward pathogenic genotypes, while representing only a small sample of the vast diversity in environmental strains. In this study, we characterized homologous recombination and structure among 152 environmental V. cholerae isolates and 13 other putative Vibrio isolates from coastal waters and sediments in central California, as well as four clinical V. cholerae isolates, using multilocus sequence analysis of seven housekeeping genes. Recombinant regions were identified by at least three detection methods in 72% of our V. cholerae isolates. Despite frequent recombination, significant linkage disequilibrium was still detected among the V. cholerae sequence types. Incongruent but nonrandom associations were observed for maximum likelihood topologies from the individual loci. Overall, our estimated recombination rate in V. cholerae of 6.5 times the mutation rate is similar to those of other sexual bacteria and appears frequently enough to restrict selection from purging much of the neutral intraspecies diversity. These data suggest that frequent recombination among V. cholerae may hinder the identification of ecotypes in this bacterioplankton population. PMID:21075874

Keymer, Daniel P.; Boehm, Alexandria B.

2011-01-01

409

Drug-sensitivity of El Tor vibrio strains isolated in the Philippines in 1964 and 1965*  

PubMed Central

About 1500 strains of El Tor vibrios, isolated in 1964 and 1965 in the Philippines, were examined for their susceptibilities to 17 drugs. All the strains tested were highly sensitive to dihydroxymethyl-furalazine, and most were highly sensitive to tetracycline hydrochloride, chloramphenicol and erythromycin, and moderately sensitive to novobiocin, dihydrostreptomycin sulfate, kanamycin and neomycin. They showed a remarkable fluctuation of sensitivity to ampicillin, cefaloridine, cefalotin and sulfafurazole, and a high resistance to benzylpenicillin sodium, oleandomycin and spiramycin. Experimental confirmation was provided of the fact that El Tor vibrios and non-agglutinable vibrios can be distinguished from classical cholera vibrios by their resistance to polymyxin B and colistin. Highly streptomycin-resistant strains, and to a lesser extent ampicillin- and sulfafurazole-resistant strains, were relatively often isolated from cholera patients who had been treated with antibiotics. One patient yielded a strain resistant to tetracycline, chloramphenicol, streptomycin and sulfafurazole. PMID:4870079

Kuwahara, Shogo; Goto, Sachiko; Kimura, Masatake; Abe, Hisao

1967-01-01

410

Polyphyly of non-bioluminescent Vibrio fischeri sharing a lux-locus deletion  

E-print Network

This study reports the first description and molecular characterization of naturally occurring, non-bioluminescent strains of Vibrio fischeri. These ‘dark’V. fischeri strains remained non-bioluminescent even after treatment ...

Wollenberg, M. S.

411

Constitutive Type VI Secretion System Expression Gives Vibrio cholerae Intra- and Interspecific Competitive Advantages  

E-print Network

The type VI secretion system (T6SS) mediates protein translocation across the cell membrane of Gram-negative bacteria, including Vibrio cholerae – the causative agent of cholera. All V. cholerae strains examined to date ...

Unterweger, Daniel

412

Experimental Reservoirs of Human Pathogens: The Vibrio Cholerae Paradigm (7th Annual SFAF Meeting, 2012)  

ScienceCinema

Rita Colwell on "Experimental Reservoirs of Human Pathogens: The Vibrio cholerae paradigm" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.

Colwell, Rita [University of Maryland

2013-02-12

413

Local Mobile Gene Pools Rapidly Cross Species Boundaries To Create within Global Vibrio cholerae Populations  

E-print Network

Vibrio cholerae represents both an environmental pathogen and a widely distributed microbial species comprised of closely related strains occurring in the tropical to temperate coastal ocean across the globe (Colwell RR, ...

Boucher, Yan

414

DIFFERENTIAL EFFECTS OF OYSTER (CRASSOSTREA VIRGINICA) DEFENSES ON CLINICAL AND ENVIRONMENTAL ISOLATES OF VIBRIO PARAHEMOLYTICUS  

EPA Science Inventory

Three clinical (2030, 2062, and 2107) and three environmental (1094, 1163, and ATCC 17802) isolates of Vibrio parahaemolyticus were exposed to hemocytes and plasma collected from oysters (Crassostrea virginica) to determine their susceptibility to putative oyster defenses. Clinic...

415

INFLUENCE OF SEASONAL FACTORS ON OYSTER HEMOCYTE KILLING OF VIBRIO PARAHEMOLYTICUS  

EPA Science Inventory

Seasonal variation of cellular defenses of oyster Crassostrea virginica against Vibrio parahaemolyticus were examined from June 1997 to December 1998 using a recently developed bactericidal assay that utilizes a tetrazolium dye. Mean hemocyte numbers, plasma lysozyme, and P. mari...

416

The Association of Virulent Vibrio Spp. Bacteria on Gafftopsail and Hardhead Catfish in Galveston Bay  

E-print Network

Vibrio vulnificus (Vv) and V. parahaemolyticus (Vp) are gram negative, halophilic bacteria that occur naturally in estuarine waters of Galveston Bay. Both bacteria have the potential to cause infections in humans either via consumption or direct...

Gilbert, Leslie Deanne

2011-10-21

417

Complete Genome Sequence for the Shellfish Pathogen Vibrio coralliilyticus RE98 Isolated from a Shellfish Hatchery  

PubMed Central

Vibrio coralliilyticus is a pathogen of corals and larval shellfish. Publications on strain RE98 list it as a Vibrio tubiashii; however, whole genome sequencing confirms RE98 as V. coralliilyticus containing a total of 6,037,824 bp consisting of two chromosomes (3,420,228 and 1,917,482 bp) and two megaplasmids (380,714 and 319,400 bp). PMID:25523764

Bono, James L.; Watson, Michael A.; Needleman, David S.

2014-01-01

418

Genome Sequence of Vibrio cholerae Strain O1 Ogawa El Tor, Isolated in Mexico, 2013  

PubMed Central

We present the draft genome sequence of Vibrio cholerae InDRE 3140 recovered in 2013 during a cholera outbreak in Mexico. The genome showed the Vibrio 7th pandemic islands VSP1 and VSP2, the pathogenic islands VPI-1 and VPI-2, the integrative and conjugative element SXT/R391 (ICE-SXT), and both prophages CTX? and RS1?. PMID:25359919

Hernández-Monroy, Irma; López-Martínez, Irma; Ortiz-Alcántara, Joanna; González-Durán, Elizabeth; Ruiz-Matus, Cuitláhuac; Kuri-Morales, Pablo; Ramírez-González, José Ernesto

2014-01-01

419

Complete Genome Sequence for the Shellfish Pathogen Vibrio coralliilyticus RE98 Isolated from a Shellfish Hatchery.  

PubMed

Vibrio coralliilyticus is a pathogen of corals and larval shellfish. Publications on strain RE98 list it as a Vibrio tubiashii; however, whole genome sequencing confirms RE98 as V. coralliilyticus containing a total of 6,037,824 bp consisting of two chromosomes (3,420,228 and 1,917,482 bp) and two megaplasmids (380,714 and 319,400 bp). PMID:25523764

Richards, Gary P; Bono, James L; Watson, Michael A; Needleman, David S

2014-01-01

420

Real-Time PCR Assays for Quantification and Differentiation of Vibrio vulnificus Strains in Oysters and Water?  

PubMed Central

Vibrio vulnificus is an autochthonous estuarine bacterium and a pathogen that is frequently transmitted via raw shellfish. Septicemia can occur within 24 h; however, isolation and confirmation from water and oysters require days. Real-time PCR assays were developed to detect and differentiate two 16S rRNA variants, types A and B, which were previously associated with environmental sources and clinical fatalities, respectively. Both assays could detect 102 to 103 V. vulnificus total cells in seeded estuarine water and in oyster homogenates. PCR assays on 11 reference V. vulnificus strains and 22 nontarget species gave expected results (type A or B for V. vulnificus and negative for nontarget species). The relationship between cell number and cycle threshold for the assays was linear (R2 = >0.93). The type A/B ratio of Florida clinical isolates was compared to that of isolates from oysters harvested in Florida waters. This ratio was 19:17 in clinical isolates and 5:8 (n = 26) in oysters harvested from restricted sites with poor water quality but was 10:1 (n = 22) in oysters from permitted sites with good water quality. A substantial percentage of isolates from oysters (19.4%) were type AB (both primer sets amplified), but no isolates from overlying waters were type AB. The real-time PCR assays were sensitive, specific, and quantitative in water samples and could also differentiate the strains in oysters without requiring isolation of V. vulnificus and may therefore be useful for rapid detection of the pathogen in shellfish and water, as well as further investigation of its population dynamics. PMID:18245234

Gordon, Katrina V.; Vickery, Michael C.; DePaola, Angelo; Staley, Christopher; Harwood, Valerie J.

2008-01-01

421

Implications of Chitin Attachment for the Environmental Persistence and Clinical Nature of the Human Pathogen Vibrio vulnificus  

PubMed Central

Vibrio vulnificus naturally inhabits a variety of aquatic organisms, including oysters, and is the leading cause of seafood-related death in the United States. Strains of this bacterium are genetically classified into environmental (E) and clinical (C) genotypes, which correlate with source of isolation. E-genotype strains integrate into marine aggregates more efficiently than do C-genotype strains, leading to a greater uptake of strains of this genotype by oysters feeding on these aggregates. The causes of this increased integration of E-type strains into marine “snow” have not been demonstrated. Here, we further investigate the physiological and genetic causalities for this genotypic heterogeneity by examining the ability of strains of each genotype to attach to chitin, a major constituent of marine snow. We found that E-genotype strains attach to chitin with significantly greater efficiency than do C-genotype strains when incubated at 20°C. Type IV pili were implicated in chitin adherence, and even in the absence of chitin, the expression level of type IV pilin genes (pilA, pilD, and mshA) was found to be inherently higher by E genotypes than by C genotypes. In contrast, the level of expression of N-acetylglucosamine binding protein A (gbpA) was significantly higher in C-genotype strains. Interestingly, incubation at a clinically relevant temperature (37°C) resulted in a significant increase in C-genotype attachment to chitin, which subsequently provided a protective effect against exposure to acid or bile, thus offering a clue into their increased incidence in human infections. This study suggests that C- and E-genotype strains have intrinsically divergent physiological programs, which may help explain the observed differences in the ecology and pathogenic potential between these two genotypes. PMID:24362430

Williams, Tiffany C.; Ayrapetyan, Mesrop

2014-01-01

422

Phaeobacter gallaeciensis Reduces Vibrio anguillarum in Cultures of Microalgae and Rotifers, and Prevents Vibriosis in Cod Larvae  

PubMed Central

Phaeobacter gallaeciensis can antagonize fish-pathogenic bacteria in vitro, and the purpose of this study was to evaluate the organism as a probiont for marine fish larvae and their feed cultures. An in vivo mechanism of action of the antagonistic probiotic bacterium is suggested using a non-antagonistic mutant. P. gallaeciensis was readily established in axenic cultures of the two microalgae Tetraselmis suecica and Nannochloropsis oculata, and of the rotifer Brachionus plicatilis. P. gallaeciensis reached densities of 107 cfu/ml and did not adversely affect growth of algae or rotifers. Vibrio anguillarum was significantly reduced by wild-type P. gallaeciensis, when introduced into these cultures. A P. gallaeciensis mutant that did not produce the antibacterial compound tropodithietic acid (TDA) did not reduce V. anguillarum numbers, suggesting that production of the antibacterial compound is important for the antagonistic properties of P. gallaeciensis. The ability of P. gallaeciensis to protect fish larvae from vibriosis was determined in a bath challenge experiment using a multidish system with 1 larva per well. Unchallenged larvae reached 40% accumulated mortality which increased to 100% when infected with V. anguillarum. P. gallaeciensis reduced the mortality of challenged cod larvae (Gadus morhua) to 10%, significantly below the levels of both the challenged and the unchallenged larvae. The TDA mutant reduced mortality of the cod larvae in some of the replicates, although to a much lesser extent than the wild type. It is concluded that P. gallaeciensis is a promising probiont in marine larviculture and that TDA production likely contributes to its probiotic effect. PMID:22928051

D’Alvise, Paul W.; Lillebø, Siril; Prol-Garcia, Maria J.; Wergeland, Heidrun I.; Nielsen, Kristian F.; Bergh, Øivind; Gram, Lone

2012-01-01

423

Quorum sensing-dependent metalloprotease VvpE is important in the virulence of Vibrio vulnificus to invertebrates.  

PubMed

Vibrio vulnificus, a Gram-negative bacterium, is an opportunistic human pathogen responsible for fatal septicemia caused by contaminated sea foods in eastern Asia. Quorum sensing (QS) is a cell-density dependent gene regulation mechanism that controls the expression of many virulence genes in various bacteria and V. vulnificus has been also suggested to express their virulence genes through the QS system. In this study, we investigated the role of QS system and QS-regulated exoproteases in the virulence of V. vulnificus using several invertebrate host models, Tenebrio molitor, an insect, Caenorhabditis elegans, a nematode, and brine shrimp (Artemia), an aquatic crustacean. When the culture supernatant of smcR (major QS regulator of V. vulnificus) mutant was injected to T. molitor larvae, it failed to induce the melanization of T. molitor larvae, while the culture supernatant of luxO (upstream negative regulator of smcR) mutant more strongly induced the melanization than wild type. These results demonstrated that QS system of V. vulnificus is crucial for virulence to T. molitor larvae. Among several QS-dependently expressed exoproteases of V. vulnificus, vvpE encoding a metalloprotease was mainly responsible for the melanization of T. molitor larvae, in that the culture supernatant of vvpE mutant failed to induce the melanization. This result was confirmed using the C. elegans and Artemia salina model systems, in which the vvpE mutant strains were attenuated in killing C. elegans and A. salina, compared with wild type, indicating that VvpE is important in the infection of V. vulnificus. In conclusion, we suggest that QS system and a QS-dependent exoprotease, VvpE are crucial for the V. vulnificus virulence to invertebrates. PMID:24769338

Ha, Changwan; Kim, Soo-Kyoung; Lee, Mi-Nan; Lee, Joon-Hee

2014-01-01

424

Snapshot of Vibrio parahaemolyticus densities in open and closed shellfish beds in Coastal South Carolina and Mississippi.  

PubMed

Vibrio parahaemolyticus is a Gram negative, halophilic bacterium that is ubiquitous in warm, tropical waters throughout the world. It is a major cause of seafood-associated gastroenteritis and is generally associated with consumption of raw or undercooked seafood, especially oysters. This study presents a snapshot of total V. parahaemolyticus densities in surface waters and shellstock American oysters (Crassostrea virginica) from open and closed shellfish harvesting areas, as well as "more rural areas" on two different US coasts, the Atlantic and the Gulf. Sampling was conducted from 2001 to 2003 at five sites near Charleston/Georgetown, SC and at four locations in the Gulfport/Pascagoula, MS area. V. parahaemolyticus numbers were determined by a direct plating method using an alkaline-phosphatase-labeled DNA probe targeting the species-specific thermolabile hemolysin gene (tlh) that was used for identification of bacterial isolates. The greatest difference between the two coasts was salinity; mean salinity in SC surface waters was 32.9 ppt, whereas the mean salinity in MS waters was 19.2 ppt, indicating more freshwater input into MS shellfish harvesting areas during the study period. The mean V. parahaemolyticus numbers in oysters were almost identical between the two states (567.4 vs. 560.1 CFU/g). Bacterial numbers in the majority of surface water samples from both states were at or below the limit of detection (LOD?=?<10 CFU/mL). The bacterial concentrations determined during this study predict a low public health risk from consumption of oysters in shellfish growing areas on either the Gulf or the Atlantic US coast. PMID:25106119

Moore, J Gooch; Ruple, A; Ballenger-Bass, K; Bell, S; Pennington, P L; Scott, G I

2014-11-01

425

Genetic Relationships of Vibrio parahaemolyticus Isolates from Clinical, Human Carrier, and Environmental Sources in Thailand, Determined by Multilocus Sequence Analysis  

PubMed Central

Vibrio parahaemolyticus is a seafood-borne pathogenic bacterium that is a major cause of gastroenteritis worldwide. We investigated the genetic and evolutionary relationships of 101 V. parahaemolyticus isolates originating from clinical, human carrier, and various environmental and seafood production sources in Thailand using multilocus sequence analysis. The isolates were recovered from clinical samples (n = 15), healthy human carriers (n = 18), various types of fresh seafood (n = 18), frozen shrimp (n = 16), fresh-farmed shrimp tissue (n = 18), and shrimp farm water (n = 16). Phylogenetic analysis revealed a high degree of genetic diversity within the V. parahaemolyticus population, although isolates recovered from clinical samples and from farmed shrimp and water samples represented distinct clusters. The tight clustering of the clinical isolates suggests that disease-causing isolates are not a random sample of the environmental reservoir, although the source of infection remains unclear. Extensive serotypic diversity occurred among isolates representing the same sequence types and recovered from the same source at the same time. These findings suggest that the O- and K-antigen-encoding loci are subject to exceptionally high rates of recombination. There was also strong evidence of interspecies horizontal gene transfer and intragenic recombination involving the recA locus in a large proportion of isolates. As the majority of the intragenic recombinational exchanges involving recA occurred among clinical and carrier isolates, it is possible that the human intestinal tract serves as a potential reservoir of donor and recipient strains that is promoting horizontal DNA transfer, driving evolutionary change, and leading to the emergence of new, potentially pathogenic strains. PMID:23377932

Theethakaew, Chonchanok; Feil, Edward J.; Castillo-Ramírez, Santiago; Aanensen, David M.; Suthienkul, Orasa; Neil, Douglas M.

2013-01-01

426

Apparent Loss of Vibrio vulnificus from North Carolina Oysters Coincides with a Drought-Induced Increase in Salinity  

PubMed Central

Despite years of successful isolation of Vibrio vulnificus from estuarine waters, beginning in 2007, it was extremely difficult to culture V. vulnificus from either North Carolina estuarine water or oyster samples. After employing culture-based methods as well as PCR and quantitative PCR for the detection of V. vulnificus, always with negative results, we concluded that this pathogen had become nearly undetectable in the North Carolina estuarine ecosystem. We ensured that the techniques were sound by seeding North Carolina oysters with V. vulnificus and performing the same tests as those previously conducted on unadulterated oysters. V. vulnificus was readily detected in the seeded oysters using both classes of methods. Furthermore, oysters were obtained from the Gulf of Mexico, and V. vulnificus was easily isolated, confirming that the methodology was sound but that the oysters and waters of North Carolina were lacking the V. vulnificus population studied for decades. Strikingly, the apparent loss of detectable V. vulnificus coincided with the most severe drought in the history of North Carolina. The drought continued until the end of 2009, with an elevated water column salinity being observed throughout this period and with V. vulnificus being nearly nonexistent. When salinities returned to normal after the drought abated in 2010, we were again able to routinely isolate V. vulnificus from the water column, although we were s