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Sample records for bacterium vibrio gazogenes

  1. Aflatoxin-Exposure of Vibrio gazogenes as a Novel System for the Generation of Aflatoxin Synthesis Inhibitors.

    Science.gov (United States)

    Gummadidala, Phani M; Chen, Yung Pin; Beauchesne, Kevin R; Miller, Kristen P; Mitra, Chandrani; Banaszek, Nora; Velez-Martinez, Michelle; Moeller, Peter D R; Ferry, John L; Decho, Alan W; Chanda, Anindya

    2016-01-01

    Aflatoxin is a mycotoxin and a secondary metabolite, and the most potent known liver carcinogen that contaminates several important crops, and represents a significant threat to public health and the economy. Available approaches reported thus far have been insufficient to eliminate this threat, and therefore provide the rational to explore novel methods for preventing aflatoxin accumulation in the environment. Many terrestrial plants and microbes that share ecological niches and encounter the aflatoxin producers have the ability to synthesize compounds that inhibit aflatoxin synthesis. However, reports of natural aflatoxin inhibitors from marine ecosystem components that do not share ecological niches with the aflatoxin producers are rare. Here, we show that a non-pathogenic marine bacterium, Vibrio gazogenes, when exposed to low non-toxic doses of aflatoxin B1, demonstrates a shift in its metabolic output and synthesizes a metabolite fraction that inhibits aflatoxin synthesis without affecting hyphal growth in the model aflatoxin producer, Aspergillus parasiticus. The molecular mass of the predominant metabolite in this fraction was also different from the known prodigiosins, which are the known antifungal secondary metabolites synthesized by this Vibrio. Gene expression analyses using RT-PCR demonstrate that this metabolite fraction inhibits aflatoxin synthesis by down-regulating the expression of early-, middle-, and late- growth stage aflatoxin genes, the aflatoxin pathway regulator, aflR and one global regulator of secondary metabolism, laeA. Our study establishes a novel system for generation of aflatoxin synthesis inhibitors, and emphasizes the potential of the under-explored Vibrio's silent genome for generating new modulators of fungal secondary metabolism. PMID:27375561

  2. Aflatoxin-exposure of Vibrio gazogenes as a novel system for the generation of aflatoxin synthesis inhibitors

    Directory of Open Access Journals (Sweden)

    Phani M Gummadidala

    2016-06-01

    Full Text Available Aflatoxin is a mycotoxin and a secondary metabolite, and the most potent known liver carcinogen that contaminates several important crops, and represents a significant threat to public health and the economy. Available approaches reported thus far have been insufficient to eliminate this threat, and therefore provide the rational to explore novel methods for preventing aflatoxin accumulation in the environment. Many terrestrial plants and microbes that share ecological niches and encounter the aflatoxin producers have the ability to synthesize compounds that inhibit aflatoxin synthesis. However, reports of natural aflatoxin inhibitors from marine ecosystem components that do not share ecological niches with the aflatoxin producers are rare. Here we show that a non-pathogenic marine bacterium, Vibrio gazogenes, when exposed to low non-toxic doses of aflatoxin B1, demonstrates a shift in its metabolic output and synthesizes a metabolite fraction that inhibits aflatoxin synthesis without affecting hyphal growth in the model aflatoxin producer, Aspergillus parasiticus. The molecular mass of the predominant metabolite in this fraction was also different from the known prodigiosins, which are the known antifungal secondary metabolites synthesized by this Vibrio. Gene expression analyses using RT-PCR demonstrate that this metabolite fraction inhibits aflatoxin synthesis by down-regulating the expression of early-, middle- and late- growth stage aflatoxin genes, the aflatoxin pathway regulator, aflR and one global regulator of secondary metabolism, LaeA. Our study establishes a novel system for generation of aflatoxin synthesis inhibitors, and emphasizes the potential of the under-explored Vibrio’s silent genome for generating new modulators of fungal secondary metabolism.

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

    OpenAIRE

    Harold J. Schreier; Schott, Eric J.

    2014-01-01

    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.

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

    OpenAIRE

    Bieger, C D; I. P. Crawford

    1983-01-01

    Tryptophan biosynthetic enzyme levels in wild-type Vibrio harveyi and a number of tryptophan auxotrophs of this species were coordinately regulated over a 100-fold range of specific activities. The tryptophan analog indoleacrylic acid evoked substantial derepression of the enzymes in wild-type cells. Even higher enzyme levels were attained in auxotrophs starved for tryptophan, regardless of the location of the block in the pathway. A derepressed mutant selected by resistance to 5-fluorotrypto...

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

    OpenAIRE

    Harwood-Sears, V; Gordon, A S

    1990-01-01

    Growth of the marine bacterium Vibrio alginolyticus is temporarily inhibited by micromolar levels of copper. During the copper-induced lag phase, supernatant compounds which complex and detoxify copper are produced. In this study two copper-inducible supernatant proteins having molecular masses of ca. 21 and 19 kilodaltons (CuBP1 and CuBP2) were identified; these proteins were, respectively, 25 and 46 times amplified in supernatants of copper-challenged cultures compared with controls. Experi...

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

    OpenAIRE

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

    2000-01-01

    Inoculation of the coral-bleaching bacterium Vibrio shiloi into seawater containing its host Oculina patagonica led to adhesion of the bacteria to the coral surface via a β-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 anti-V. shiloi antibodies to stain the intracellular bacteria. At 29°C, 80% of the bac...

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

    Science.gov (United States)

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

    1997-01-01

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

  8. Microbially influenced corrosion of stainless steel by marine bacterium Vibrio natriegens: (I) Corrosion behavior

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Sha; Tian Jintao [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Chen Shougang, E-mail: sgchen@ouc.edu.cn [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Lei Yanhua; Chang Xueting; Liu Tao [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Yin Yansheng, E-mail: yys2006@ouc.edu.cn [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China)

    2009-04-30

    The microbially influenced corrosion of stainless steel (SS) by marine bacterium Vibrio natriegens (V. natriegens) was investigated using surface analysis (atomic force microscopy (AFM), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDXA)) and electrochemical techniques (the open circuit potential, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization curves ). AFM images corroborated the results from the EIS models which show biofilm attachment and subsequent detachment over time. The SEM images revealed the occurrence of micro-pitting corrosion underneath the biofilms on the metal surface after the biofilm removal. The presence of carbon, oxygen, phosphor and sulfur obtained from EDXA proved the formation of biofilm. The electrochemical results showed that the corrosion of SS was accelerated in the presence of V. natriegens based on the decrease in the resistance of the charge transfer resistance (R{sub ct}) obtained from EIS and the increase in corrosion current densities obtained from potentiodynamic polarization curves.

  9. Microbially influenced corrosion of 303 stainless steel by marine bacterium Vibrio natriegens: (II) Corrosion mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Yin Yansheng, E-mail: yys2006@ouc.edu.cn [Institute of Ocean Materials and Engineering, Shanghai Maritime University, Shanghai 200135 (China); Cheng Sha [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Chen Shougang, E-mail: sgchen@ouc.edu.cn [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Tian Jintao; Liu Tao; Chang Xueting [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China)

    2009-04-30

    Electrochemical techniques (electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves) and surface analysis (scanning electron microscopy (SEM)) were carried out to determine the possible mechanism of the microbially influenced corrosion of 303 stainless steel (303 SS) by marine bacterium Vibrio natriegens (V. natriegens). In order to clarify the mechanism, 303 SS coupons were immersed in four different mediums. EIS results were interpreted with different equivalent circuits to model the physicoelectric characteristics of the electrode/biofilm/solution interface. The results showed that N{sub 2}-fixation actually promoted the corrosion of 303 SS; however, the influence of the produced NH{sub 3} was negligible. It can be speculated that the electron transfer and/or the nitrogenase catalyzing the process may influence the corrosion.

  10. Vibrio ruber (S2A1, a Marine Bacterium that Exhibits Significant Antimicrobial Activity

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    Wan Norhana, N.

    2005-01-01

    Full Text Available A potential antimicrobial-producing marine bacterium, designated as S2A1, was isolated from a seagrass collected in Setiu Lagoon, Terengganu. S2A1 was a Gram negative rod that was motile by means of a polar flagellum. Phenotypic and genotypic characterisation indicated that strain S2A1 represented a species in the genus Vibrio. The antimicrobial activities of S2A1 against a number of test microorganisms showed a broad antimicrobial spectrum property with inhibition towards 25 out of 29 test microorganisms. The antimicrobial compound(s of S2A1 was more effective against Gram-positive bacteria with 100% inhibition, compared to yeast (88.8% and Gram-negative bacteria (75.0% tested. High activity scores were observed when using whole cells compared to cell free extract.

  11. Microbially influenced corrosion of 303 stainless steel by marine bacterium Vibrio natriegens: (II) Corrosion mechanism

    International Nuclear Information System (INIS)

    Electrochemical techniques (electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves) and surface analysis (scanning electron microscopy (SEM)) were carried out to determine the possible mechanism of the microbially influenced corrosion of 303 stainless steel (303 SS) by marine bacterium Vibrio natriegens (V. natriegens). In order to clarify the mechanism, 303 SS coupons were immersed in four different mediums. EIS results were interpreted with different equivalent circuits to model the physicoelectric characteristics of the electrode/biofilm/solution interface. The results showed that N2-fixation actually promoted the corrosion of 303 SS; however, the influence of the produced NH3 was negligible. It can be speculated that the electron transfer and/or the nitrogenase catalyzing the process may influence the corrosion.

  12. Microbially influenced corrosion of stainless steel by marine bacterium Vibrio natriegens: (I) Corrosion behavior

    International Nuclear Information System (INIS)

    The microbially influenced corrosion of stainless steel (SS) by marine bacterium Vibrio natriegens (V. natriegens) was investigated using surface analysis (atomic force microscopy (AFM), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDXA)) and electrochemical techniques (the open circuit potential, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization curves ). AFM images corroborated the results from the EIS models which show biofilm attachment and subsequent detachment over time. The SEM images revealed the occurrence of micro-pitting corrosion underneath the biofilms on the metal surface after the biofilm removal. The presence of carbon, oxygen, phosphor and sulfur obtained from EDXA proved the formation of biofilm. The electrochemical results showed that the corrosion of SS was accelerated in the presence of V. natriegens based on the decrease in the resistance of the charge transfer resistance (Rct) obtained from EIS and the increase in corrosion current densities obtained from potentiodynamic polarization curves.

  13. Cross-species induction of luminescence in the quorum-sensing bacterium Vibrio harveyi.

    Science.gov (United States)

    Bassler, B L; Greenberg, E P; Stevens, A M

    1997-01-01

    Different species of bacteria were tested for production of extracellular autoinducer-like activities that could stimulate the expression of the luminescence genes in Vibrio harveyi. Several species of bacteria, including the pathogens Vibrio cholerae and Vibrio parahaemolyticus, were found to produce such activities. Possible physiological roles for the two V. harveyi detection-response systems and their joint regulation are discussed. PMID:9190823

  14. Sulfonamide inhibition studies of the β-carbonic anhydrase from the pathogenic bacterium Vibrio cholerae.

    Science.gov (United States)

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

    2016-03-01

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

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

    Science.gov (United States)

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

    2016-03-01

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

  16. Antibacterial Property of a Coral-Associated Bacterium Pseudoalteromonas luteoviolacea Against Shrimp Pathogenic Vibrio harveyi (In Vitro Study

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    OCKY KARNA RADJASA

    2005-06-01

    Full Text Available A coral-associated bacterium was successfully screened for secondary metabolites production based on PCR amplification of the nonribosomal peptide synthetase gene and was identified as closely related to Pseudoalteromonas luteoviolacea based on its 16S rDNA.The bacterium was found to inhibit the growth of shrimp pathogenic bacterium tested, Vibrio harveyi. To characterize the inhibiting metabolite, a 279 bp long DNA fragment was obtained and the deduced amino acid sequence showed conserved signature regions for peptide synthetases and revealed a high similarity to NosD (40% identity, a multifunctional peptide synthetase from Nostoc sp. GSV224, and NdaB (44% identity, a peptide synthetase module of Nodularia spumigena.

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

    Science.gov (United States)

    Ortiz de García, Sheyla; García-Encina, Pedro A; Irusta-Mata, Rubén

    2016-01-01

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

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

    Science.gov (United States)

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

    2012-12-13

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

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

    Science.gov (United States)

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

    2015-01-01

    Vibrio harveyi is a Gram-negative marine γ-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

  20. Molecular uptake of chitooligosaccharides through chitoporin from the marine bacterium Vibrio harveyi.

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    Wipa Suginta

    Full Text Available 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 NH(3. 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.

  1. Role of Chitin-Binding Proteins in the Specific Attachment of the Marine Bacterium Vibrio harveyi to Chitin

    Science.gov (United States)

    Montgomery, Michael T.; Kirchman, David L.

    1993-01-01

    We examined the mechanism of attachment of the marine bacterium Vibrio harveyi to chitin. Wheat germ agglutinin and chitinase bind to chitin and competitively inhibited the attachment of V. harveyi to chitin, but not to cellulose. Bovine serum albumin and cellulase do not bind to chitin and had no effect on bacterial attachment to chitin. These data suggest that this bacterium recognizes specific attachment sites on the chitin particle. The level of attachment of a chitinase-overproducing mutant of V. harveyi to chitin was about twice as much as that of the uninduced wild type. Detergent-extracted cell membranes inhibited attachment and contained a 53-kDa peptide that was overproduced by the chitinase-overproducing mutant. Three peptides (40, 53, and 150 kDa) were recovered from chitin which had been exposed to membrane extracts. Polyclonal antibodies raised against extracellular chitinase cross-reacted with the 53- and 150-kDa chitin-binding peptides and inhibited attachment, probably by sterically hindering interactions between the chitin-binding peptides and chitin. The 53- and 150-kDa chitin-binding peptides did not have chitinase activity. These results suggest that chitin-binding peptides, especially the 53-kDa chitin-binding peptide and chitinase and perhaps the 150-kDa peptide, mediate the specific attachment of V. harveyi to chitin. Images PMID:16348865

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

    Science.gov (United States)

    Sirimontree, Paknisa; Fukamizo, Tamo; Suginta, Wipa

    2016-02-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Byers, D.M.

    1989-01-01

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

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

    International Nuclear Information System (INIS)

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

  5. Characterizing the host and symbiont proteomes in the association between the Bobtail squid, Euprymna scolopes, and the bacterium, Vibrio fischeri.

    Directory of Open Access Journals (Sweden)

    Tyler R Schleicher

    Full Text Available 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.

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

    Science.gov (United States)

    Zhu, Benwei; Ning, Limin

    2016-02-28

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

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

    Science.gov (United States)

    Villa, Sara; Vighi, Marco; Finizio, Antonio

    2014-08-01

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

  8. Cell division licensing in the multi-chromosomal Vibrio cholerae bacterium.

    Science.gov (United States)

    Galli, Elisa; Poidevin, Mickaël; Le Bars, Romain; Desfontaines, Jean-Michel; Muresan, Leila; Paly, Evelyne; Yamaichi, Yoshiharu; Barre, François-Xavier

    2016-01-01

    Cell division must be coordinated with chromosome replication and segregation to ensure the faithful transmission of genetic information during proliferation. In most bacteria, assembly of the division apparatus, the divisome, starts with the polymerization of a tubulin homologue, FtsZ, into a ring-like structure at mid-cell, the Z-ring(1). It typically occurs at half of the cell cycle when most of the replication and segregation cycle of the unique chromosome they generally harbour is achieved(2). The chromosome itself participates in the regulation of cell division, at least in part because it serves as a scaffold to position FtsZ polymerization antagonists(3). However, about 10% of bacteria have more than one chromosome(4), which raises questions about the way they license cell division(3). For instance, the genome of Vibrio cholerae, the agent of cholera, is divided between a 3 Mbp replicon that originates from the chromosome of its mono-chromosomal ancestor, Chr1, and a 1 Mbp plasmid-derived replicon, Chr2 (ref. 5). Here, we show that Chr2 harbours binding motifs for an inhibitor of Z-ring formation, which helps accurately position the V. cholerae divisome at mid-cell and postpones its assembly to the very end of the cell cycle. PMID:27562255

  9. Induction of Chitin-Binding Proteins during the Specific Attachment of the Marine Bacterium Vibrio harveyi to Chitin

    Science.gov (United States)

    Montgomery, Michael T.; Kirchman, David L.

    1994-01-01

    Previous work has shown that attachment of Vibrio harveyi to chitin is specific and involves at least two chitin-binding peptides. However, the roles and regulation of these chitin-binding peptides in attachment are still unclear. Here we show that preincubation with the oligomeric sugars composing chitin stimulated chitinase activity, cellular attachment to chitin, and production of chitin-binding peptides. One of these peptides, a 53-kDa peptide, is produced constitutively and appears to mediate initial attachment to chitin. Synthesis of another peptide, a 150-kDa chitin-binding peptide, is induced by chitin and thus may be involved in time-dependent attachment. Coordinated regulation of attachment and degradation of chitin may give bacteria like V. harveyi a selective advantage over other bacteria in nutrient-poor aquatic environments. Images PMID:16349455

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

    Science.gov (United States)

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

    2015-07-31

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

  11. Anion inhibition profiles of α-, β- and γ-carbonic anhydrases from the pathogenic bacterium Vibrio cholerae.

    Science.gov (United States)

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

    2016-08-15

    Among the numerous metalloenzymes known to date, carbonic anhydrase (CA, EC 4.2.1.1) was the first zinc containing one, being discovered decades ago. CA is a hydro-lyase, which catalyzes the following hydration-dehydration reaction: CO2+H2O⇋HCO3(-)+H(+). Several CA classes are presently known, including the α-, β-, γ-, δ-, ζ- and η-CAs. In prokaryotes, the existence of genes encoding CAs from at least three classes (α-, β- and γ-class) suggests that these enzymes play a key role in the physiology of these organisms. In many bacteria CAs are essential for the life cycle of microbes and their inhibition leads to growth impairment or growth defects of the pathogen. CAs thus started to be investigated in detail in bacteria, fungi and protozoa with the aim to identify antiinfectives with a novel mechanism of action. Here, we investigated the catalytic activity, biochemical properties and anion inhibition profiles of the three CAs from the bacterial pathogen Vibrio cholera, VchCA, VchCAβ and VchCAγ. The three enzymes are efficient catalysts for CO2 hydration, with kcat values ranging between (3.4-8.23)×10(5)s(-1) and kcat/KM of (4.1-7.0)×10(7)M(-1)s(-1). A set of inorganic anions and small molecules was investigated for inhibition of these enzymes. The most potent VchCAγ inhibitors were N,N-diethyldithiocarbamate, sulfamate, sulfamide, phenylboronic acid and phenylarsonic acid, with KI values ranging between 44 and 91μM. PMID:27283786

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

    Science.gov (United States)

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

    2016-04-15

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

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

    Science.gov (United States)

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

    2014-09-01

    Nitrogen (N) isotopic compositions of individual hydrolysable amino acids (δ15NAAs) in N pools have been increasingly used for trophic position assessment and evaluation of sources and transformation processes of organic matter in marine environments. However, there are limited data about variability in δ15NAAs patterns and how this variability influences marine bacteria, an important mediator of trophic transfer and organic matter transformation. We explored whether marine bacterial δ15NAAs profiles change depending on the type and C:N ratio of the substrate. The δ15NAAs profile of a marine bacterium, Vibrio harveyi, was examined using medium containing either glutamate, alanine or ammonium as the N source [substrate C:N ratios (range, 3 to 20) were adjusted with glucose]. The data were interpreted as a reflection of isotope fractionations associated with de novo synthesis of amino acids by bacteria. Principal component analysis (PCA) using the δ15N offset values normalized to glutamate + glutamine δ15N revealed that δ15NAAs profiles differed depending on the N source and C:N ratio of the substrate. High variability in the δ15N offset of alanine and valine largely explained this bacterial δ15NAAs profile variability. PCA was also conducted using bacterial and phytoplankton (cyanobacteria and eukaryotic algae) δ15NAAs profile data reported previously. The results revealed that bacterial δ15NAAs patterns were distinct from those of phytoplankton. Therefore, the δ15NAAs profile is a useful indicator of biochemical responses of bacteria to changes in substrate conditions, serving as a potentially useful method for identifying organic matter sources in marine environments.

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

    Directory of Open Access Journals (Sweden)

    Nurhidayu Al-Saari

    Full Text Available Advances in genomic microbial taxonomy have opened the way to create a more universal and transparent concept of species but is still in a transitional stage towards becoming a defining robust criteria for describing new microbial species with minimum features obtained using both genome and classical polyphasic taxonomies. Here we performed advanced microbial taxonomies combined with both genome-based and classical approaches for new agarolytic vibrio isolates to describe not only a novel Vibrio species but also a member of a new Vibrio clade. Two novel vibrio strains (Vibrio astriarenae sp. nov. C7T and C20 showing agarolytic, halophilic and fermentative metabolic activity were isolated from a seawater sample collected in a coral reef in Okinawa. Intraspecific similarities of the isolates were identical in both sequences on the 16S rRNA and pyrH genes, but the closest relatives on the molecular phylogenetic trees on the basis of 16S rRNA and pyrH gene sequences were V. hangzhouensis JCM 15146T (97.8% similarity and V. agarivorans CECT 5085T (97.3% similarity, respectively. Further multilocus sequence analysis (MLSA on the basis of 8 protein coding genes (ftsZ, gapA, gyrB, mreB, pyrH, recA, rpoA, and topA obtained by the genome sequences clearly showed the V. astriarenae strain C7T and C20 formed a distinct new clade protruded next to V. agarivorans CECT 5085T. The singleton V. agarivorans has never been included in previous MLSA of Vibrionaceae due to the lack of some gene sequences. Now the gene sequences are completed and analysis of 100 taxa in total provided a clear picture describing the association of V. agarivorans into pre-existing concatenated network tree and concluded its relationship to our vibrio strains. Experimental DNA-DNA hybridization (DDH data showed that the strains C7T and C20 were conspecific but were separated from all of the other Vibrio species related on the basis of both 16S rRNA and pyrH gene phylogenies (e.g., V

  15. Vibrio population structure - Genetic and population structure analysis of clinical and environmental Vibrio parahaemolyticus strains

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Vibrio parahaemolyticus (Vp) is a marine bacterium capable of causing severe gastroenteritis in humans, usually through the consumption of raw shellfish. Before...

  16. Vibrio Cholerae

    OpenAIRE

    Sri Amelia

    2006-01-01

    Vibrio cholerae adalah salah satu bakteri yang masuk dalam family Vibrionaceae selain dari Aeromonas dan Plesiomonas, dan merupakan bagian dari genus Vibrio. Bakteri ini pertama kali ditemukan oleh Robert Koch pada tahun 1884 dan sangat penting dalam dunia kedokteran karena menyebabkan penyakit kolera, oleh Sri Amelia

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

    Science.gov (United States)

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

    2015-04-01

    Vibrio harveyi β-N-acetylglucosaminidase (VhGlcNAcase) is a new member of the GH20 glycoside hydrolase family responsible for the complete degradation of chitin fragments, with N-acetylglucosamine (GlcNAc) monomers as the final products. In this study, the crystallization and preliminary crystallographic data of wild-type VhGlcNAcase and its catalytically inactive mutant D437A in the absence and the presence of substrate are reported. Crystals of wild-type VhGlcNAcase were grown in 0.1 M sodium acetate pH 4.6, 1.4 M sodium malonate, while crystals of the D437A mutant were obtained in 0.1 M bis-tris pH 7.5, 0.1 M sodium acetate, 20% PEG 3350. X-ray data from the wild-type and the mutant crystals were collected at a synchrotron-radiation light source and were complete to a resolution of 2.5 Å. All crystals were composed of the same type of dimer, with the substrate N,N'-diacetylglucosamine (GlcNAc₂ or diNAG) used for soaking was cleaved by the active enzyme, leaving only a single GlcNAc molecule bound to the protein. PMID:25849504

  18. Small RNA target genes and regulatory connections in the Vibrio cholerae quorum sensing system

    DEFF Research Database (Denmark)

    Hammer, Brian K; Svenningsen, Sine Lo

    2011-01-01

    The two-component quorum sensing (QS) system, first described in the marine bacterium Vibrio harveyi and evolutionarily conserved among members of the genus Vibrio, has been best studied in the human pathogen Vibrio cholerae (1, 2). In the V. cholerae QS system, the response to the accumulation of...

  19. Complete Genome Sequence of Vibrio alginolyticus ZJ-T.

    Science.gov (United States)

    Deng, Yiqin; Chen, Chang; Zhao, Zhe; Huang, Xiaochun; Yang, Yiying; Ding, Xiongqi

    2016-01-01

    Vibrio alginolyticus is a ubiquitous Gram-negative bacterium which is normally distributed in the coastal and estuarine environments. It has been suggested to be an opportunistic pathogen to both marine animals and humans, Here, the completed genome sequence of V. alginolyticus ZJ-T was determined by Illumina high-throughput sequencing. PMID:27587824

  20. Quorum-sensing regulates biofilm formation in Vibrio scophthalmi

    Directory of Open Access Journals (Sweden)

    García-Aljaro Cristina

    2012-12-01

    Full Text Available Abstract Background In a previous study, we demonstrated that Vibrio scophthalmi, the most abundant Vibrio species among the marine aerobic or facultatively anaerobic bacteria inhabiting the intestinal tract of healthy cultured turbot (Scophthalmus maximus, contains at least two quorum-sensing circuits involving two types of signal molecules (a 3-hydroxy-dodecanoyl-homoserine lactone and the universal autoinducer 2 encoded by luxS. The purpose of this study was to investigate the functions regulated by these quorum sensing circuits in this vibrio by constructing mutants for the genes involved in these circuits. Results The presence of a homologue to the Vibrio harveyi luxR gene encoding a main transcriptional regulator, whose expression is modulated by quorum–sensing signal molecules in other vibrios, was detected and sequenced. The V. scophthalmi LuxR protein displayed a maximum amino acid identity of 82% with SmcR, the LuxR homologue found in Vibrio vulnificus. luxR and luxS null mutants were constructed and their phenotype analysed. Both mutants displayed reduced biofilm formation in vitro as well as differences in membrane protein expression by mass-spectrometry analysis. Additionally, a recombinant strain of V. scophthalmi carrying the lactonase AiiA from Bacillus cereus, which causes hydrolysis of acyl homoserine lactones, was included in the study. Conclusions V. scophthalmi shares two quorum sensing circuits, including the main transcriptional regulator luxR, with some pathogenic vibrios such as V. harveyi and V. anguillarum. However, contrary to these pathogenic vibrios no virulence factors (such as protease production were found to be quorum sensing regulated in this bacterium. Noteworthy, biofilm formation was altered in luxS and luxR mutants. In these mutants a different expression profile of membrane proteins were observed with respect to the wild type strain suggesting that quorum sensing could play a role in the regulation of

  1. Biodiversity of Vibrios

    OpenAIRE

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

    2004-01-01

    Vibrios are ubiquitous and abundant in the aquatic environment. A high abundance of vibrios is also detected in tissues and/or organs of various marine algae and animals, e.g., abalones, bivalves, corals, fish, shrimp, sponges, squid, and zooplankton. Vibrios harbour a wealth of diverse genomes as revealed by different genomic techniques including amplified fragment length polymorphism, multilocus sequence typing, repetetive extragenic palindrome PCR, ribotyping, and whole-genome sequencing. ...

  2. VIBRIO CHOLERAE VPIФ/CTXФ/TCP: INTERACTIONS OF PHAGE-PHAGE-BACTERIUM%霍乱弧菌VPIФ/CTXФ/TCP体系:噬菌体-噬菌体-细菌多元作用

    Institute of Scientific and Technical Information of China (English)

    艾云灿; 孟繁梅

    2001-01-01

    @@ 霍乱由霍乱弧菌(Vibrio cholerae)菌株感染人体所引起,可导致重度脱水性腹泻,死亡率高.霍乱弧菌存在于水生环境中,人类因食用被污染的水或食物而受到感染,暴发流行.VPIФ/CTXФ/TCP体系是决定该菌侵染力和毒力的关键,它集中体现了有关噬菌体——噬菌体——宿主细菌多元作用,阐释其分子机制是目前十分活跃的研究领域[1,2].作为典型示例,这个体系突出了噬菌体介导的病原细菌毒力溶源转变、毒力基因水平转移和进化等同题[3],开创了在分子水平上研究流行病学、预防医学的新领域[4-6].

  3. Genomic taxonomy of vibrios

    DEFF Research Database (Denmark)

    Thompson, Cristiane C.; Vicente, Ana Carolina P.; Souza, Rangel C.;

    2009-01-01

    BACKGROUND: Vibrio taxonomy has been based on a polyphasic approach. In this study, we retrieve useful taxonomic information (i.e. data that can be used to distinguish different taxonomic levels, such as species and genera) from 32 genome sequences of different vibrio species. We use a variety of...... tools to explore the taxonomic relationship between the sequenced genomes, including Multilocus Sequence Analysis (MLSA), supertrees, Average Amino Acid Identity (AAI), genomic signatures, and Genome BLAST atlases. Our aim is to analyse the usefulness of these tools for species identification in vibrios....... RESULTS: We have generated four new genome sequences of three Vibrio species, i.e., V. alginolyticus 40B, V. harveyi-like 1DA3, and V. mimicus strains VM573 and VM603, and present a broad analyses of these genomes along with other sequenced Vibrio species. The genome atlas and pangenome plots provide a...

  4. Spatially selective colonization of the arthropod intestine through activation of Vibrio cholerae biofilm formation

    OpenAIRE

    Purdy, Alexandra E.; Watnick, Paula I.

    2011-01-01

    Vibrio cholerae is an estuarine bacterium and the human pathogen responsible for the diarrheal disease cholera. In the environment, arthropods are proposed to be carriers and reservoirs of V. cholerae. However, the molecular basis of the association between V. cholerae and viable arthropods has not been elucidated previously. Here, we show that the V. cholerae Vibrio polysaccharide (VPS)-dependent biofilm is highly activated upon entry into the arthropod intestine and is specifically required...

  5. The Polar Flagellar Motor of Vibrio cholerae Is Driven by an Na+ Motive Force

    OpenAIRE

    Kojima, Seiji; Yamamoto, Koichiro; Kawagishi, Ikuro; Homma, Michio

    1999-01-01

    Vibrio cholerae is a highly motile bacterium which possesses a single polar flagellum as a locomotion organelle. Motility is thought to be an important factor for the virulence of V. cholerae. The genome sequencing project of this organism is in progress, and the genes that are highly homologous to the essential genes of the Na+-driven polar flagellar motor of Vibrio alginolyticus were found in the genome database of V. cholerae. The energy source of its flagellar motor was investigated. We e...

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

    Science.gov (United States)

    Svenningsen, Sine Lo

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

  7. Shedding light on bioluminescence regulation in Vibrio fischeri

    OpenAIRE

    Miyashiro, Tim; Ruby, Edward G.

    2012-01-01

    The bioluminescence emitted by the marine bacterium Vibrio fischeri is a particularly striking result of individual microbial cells coordinating a group behavior. The genes responsible for light production are principally regulated by the LuxR-LuxI quorum-sensing system. In addition to LuxR-LuxI, numerous other genetic elements and environmental conditions control bioluminescence production. Efforts to mathematically model the LuxR-LuxI system are providing insight into the dynamics of this a...

  8. Detection of extracellular toxin(s) produced by Vibrio vulnificus.

    OpenAIRE

    Kreger, A; Lockwood, D.

    1981-01-01

    Conditions are described for the production, in high titers, a heat-labile, antigenic, extracellular toxin(s) by Vibrio vulnificus, a recently recognized human pathogen. Bacteriologically sterile culture filtrate preparations obtained from mid-logarithmic-phase cultures of the bacterium possessed cytolytic activity against mammalian erythrocytes, cytotoxic activity for Chinese hamster ovary cells, vascular permeability factor activity in guinea pig skin, and lethal activity for mice. The spec...

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

    OpenAIRE

    StefanPukatzki; DanieleProvenzano

    2013-01-01

    Diarrheal diseases are the second-most common cause of death among children under the age of five worldwide. Cholera alone, caused by the marine bacterium Vibrio cholerae, is responsible for several million cases and over 120,000 deaths annually. When contaminated water is ingested, V. cholerae passes through the gastric acid barrier, penetrates the mucin layer of the small intestine, and adheres to the underlying epithelial lining. V. cholerae multiplies rapidly, secretes cholera toxin, and ...

  10. Stabile kloningsvektorer til Vibrio cholerae

    OpenAIRE

    Cohen, Malene; Jakobsen, Henrik; Larsen, Marie B.; Rasmussen, Maria H; Schrøder, Nanna B.

    2005-01-01

    Vi har forsøgt at konstruere stabile, plasmidbaserede ekspressions-/kloningsvektorer til Vibrio cholerae. Ideelt burde sådanne vektorer baseres på naturlige plasmider fra Vibrio cholerae, men idet Vibrio cholerae sjældent indeholder plasmider, tog vi i stedet udgangspunkt i velkarakteriserede kloningsvektorer fra Escherichia coli. I projektet undersøges fire kloningsvektorer med hver deres karakteristika. Det lykkedes at indføre dem i Vibrio cholerae. Med udgangspunkt i den ene vektor vises, ...

  11. Genomic taxonomy of vibrios

    Directory of Open Access Journals (Sweden)

    Iida Tetsuya

    2009-10-01

    Full Text Available Abstract 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

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

    DEFF Research Database (Denmark)

    Holten-Andersen, Lars; Dalsgaard, Inger; Nylén, Jørgen;

    2012-01-01

    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...

  13. Septic arthritis and subsequent fatal septic shock caused by Vibrio vulnificus infection

    DEFF Research Database (Denmark)

    Emamifar, Amir; Asmussen Andreasen, Rikke; Andersen, Nanna Skaarup;

    2015-01-01

    Vibrio vulnificus is a rare but potential fatal bacterium that can cause severe infections. Wound infections, primary sepsis and gastroenteritis are the most common clinical features. Septic arthritis caused by V. vulnificus is an atypical presentation that has been reported in only two case...

  14. Vibrio vulnificus produces quorum sensing signals of the AHL-class

    DEFF Research Database (Denmark)

    Valiente, E.; Bruhn, Jesper Bartholin; Nielsen, Kristian Fog; Larsen, Jens Lauritz; Roig, F. J.; Gram, Lone; Amaro, C.

    2009-01-01

    Vibrio vulnificus is an aquatic pathogenic bacterium that can cause vibriosis in humans and fish. The species is subdivided into three biotypes with the fish-virulent strains belonging to biotype 2. The quorum sensing (QS) phenomenon mediated by furanosyl borate diester or autoinducer 2 (AI-2) has...

  15. Mlp24 (McpX) of Vibrio cholerae Implicated in Pathogenicity Functions as a Chemoreceptor for Multiple Amino Acids

    OpenAIRE

    Nishiyama, So-ichiro; Suzuki, Daisuke; Itoh, Yasuaki; Suzuki, Kazuho; Tajima, Hirotaka; Hyakutake, Akihiro; Homma, Michio; Butler-Wu, Susan M.; Camilli, Andrew; Kawagishi, Ikuro

    2012-01-01

    The chemotaxis of Vibrio cholerae, the causative agent of cholera, has been implicated in pathogenicity. The bacterium has more than 40 genes for methyl-accepting chemotaxis protein (MCP)-like proteins (MLPs). In this study, we found that glycine and at least 18 l-amino acids, including serine, arginine, asparagine, and proline, serve as attractants to the classical biotype strain O395N1. Based on the sequence comparison with Vibrio parahaemolyticus, we speculated that at least 17 MLPs of V. ...

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

    Science.gov (United States)

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

    2015-11-01

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

  17. Exopolysaccharide production by Vibrio fischeri, a fouling marine bacterium

    Digital Repository Service at National Institute of Oceanography (India)

    Rodrigues, C.L.; Bhosle, N.B

    stream_size 8 stream_content_type text/plain stream_name Biofouling_4_301.pdf.txt stream_source_info Biofouling_4_301.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

  18. Vibrio vulnificus endometritis.

    OpenAIRE

    Tison, D L; Kelly, M T

    1984-01-01

    Vibrio vulnificus most frequently causes wound infections contracted after exposure to seawater or primary septicemias resulting from the consumption of raw oysters. We report a case of endometritis caused by V. vulnificus. The infection was apparently acquired during the act of sexual intercourse in seawater in an area in which V. vulnificus has been frequently isolated. The efficacy of treatment with an antimicrobial regimen which included tetracycline is discussed.

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

    OpenAIRE

    JasonRGraff; StephanieForschner-Dancause; SusanneMenden-Deuer; RichardLong

    2013-01-01

    Vibrio cholerae is a human pathogenic marine bacterium inhabiting coastal regions and is vectored into human food and water supplies via attachment to particles including detritus, phytoplankton, and zooplankton. Particle colonization by the pathogen is inhibited by an antagonistic interaction with the particle-associated Vibrionales bacterium SWAT3, a producer of the antibiotic andrimid. By analyzing the individual movement behaviors of V. cholerae exposed to a gradient of andrimid in a micr...

  20. Temperature-Regulated Bleaching and Lysis of the Coral Pocillopora damicornis by the Novel Pathogen Vibrio coralliilyticus

    OpenAIRE

    Ben-Haim, Yael; Zicherman-Keren, Maya; Rosenberg, Eugene

    2003-01-01

    Coral bleaching is the disruption of symbioses between coral animals and their photosynthetic microalgal endosymbionts (zooxanthellae). It has been suggested that large-scale bleaching episodes are linked to global warming. The data presented here demonstrate that Vibrio coralliilyticus is an etiological agent of bleaching of the coral Pocillopora damicornis. This bacterium was present at high levels in bleached P. damicornis but absent from healthy corals. The bacterium was isolated in pure ...

  1. Vibrio chromosome-specific families

    DEFF Research Database (Denmark)

    Lukjancenko, Oksana; Ussery, David

    2014-01-01

    We have compared chromosome-specific genes in a set of 18 finished Vibrio genomes, and, in addition, also calculated the pan- and core-genomes from a data set of more than 250 draft Vibrio genome sequences. These genomes come from 9 known species and 2 unknown species. Within the finished...

  2. Moritella viscosa, a pathogenic bacterium affecting the fillet quality in fish

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian; Nielsen, Michael Engelbrecht

    2011-01-01

    Moritella viscosa is a bacterium belonging to the family Moritellaceae and was formerly known as Vibrio viscosus. The name ‘viscosa’ originates from the slimy nature of the bacterium. M. viscosa is considered to be the main causative agent of the phenomenon ‘winter ulcer’ or ‘cold-water ulcer......’ which affects various fish species in seawater during cold periods (Lunder et al. 1995). The bacterium is mainly a problem for farmed salmonid species, such as Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss), but has also been isolated from other fish species, including Atlantic...

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

    Science.gov (United States)

    Henke, Jennifer M.; Bassler, Bonnie L.

    2004-01-01

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

  4. Vibrio jasicida sp. nov., a member of the Harveyi clade, isolated from marine animals (packhorse lobster, abalone and Atlantic salmon).

    Science.gov (United States)

    Yoshizawa, Susumu; Tsuruya, Yasuhiro; Fukui, Youhei; Sawabe, Tomoo; Yokota, Akira; Kogure, Kazuhiro; Higgins, Melissa; Carson, Jeremy; Thompson, Fabiano L

    2012-08-01

    Six isolates of a facultatively anaerobic bacterium were recovered in culture from marine invertebrates and vertebrates, including packhorse lobster (Jasus verreauxi), abalone (Haliotis sp.) and Atlantic salmon (Salmo salar), between 1994 and 2002. The bacteria were Gram-negative, rod-shaped and motile by means of more than one polar flagellum, oxidase-positive, catalase-positive and able to grow in the presence of 0.5-8.0% NaCl (optimum 3.0-6.0%) and at 10-37 °C (optimum 25-30 °C). On the basis of 16S rRNA gene sequence analysis and multilocus sequence analysis (MLSA) using five loci (2443 bp; gyrB, pyrH, ftsZ, mreB and gapA), the closest phylogenetic neighbours of strain TCFB 0772(T) were the type strains of Vibrio communis (99.8 and 94.6 % similarity, respectively), Vibrio owensii (99.8 and 94.1%), Vibrio natriegens (99.4 and 88.8%), Vibrio parahaemolyticus (99.4 and 90.3%), Vibrio rotiferianus (99.2 and 94.4%), Vibrio alginolyticus (99.1 and 89.3%) and Vibrio campbellii (99.1 and 92.3%). DNA-DNA hybridization confirmed that the six isolates constitute a unique taxon that is distinct from other known species of Vibrio. In addition, this taxon can be readily differentiated phenotypically from other Vibrio species. The six isolates therefore represent a novel species, for which the name Vibrio jasicida sp. nov. is proposed; the novel species is represented by the type strain TCFB 0772(T) ( = JCM 16453(T)  = LMG 25398(T)) (DNA G+C content 45.9 mol%) and reference strains TCFB 1977 ( = JCM 16454) and TCFB 1000 ( = JCM 16455). PMID:21984666

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1988-12-31

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

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

    LENUS (Irish Health Repository)

    Matlawska-Wasowska, Ksenia

    2010-12-01

    Vibrio parahaemolyticus is a food-borne pathogen causing inflammation of the gastrointestinal epithelium. Pathogenic strains of this bacterium possess two Type III Secretion Systems (TTSS) that deliver effector proteins into host cells. In order to better understand human host cell responses to V. parahaemolyticus, the modulation of Mitogen Activated Protein Kinase (MAPK) activation in epithelial cells by an O3:K6 clinical isolate, RIMD2210633, was investigated. The importance of MAPK activation for the ability of the bacterium to be cytotoxic and to induce secretion of Interleukin-8 (IL-8) was determined.

  7. A transcriptional regulator linking quorum sensing and chitin induction to render Vibrio cholerae naturally transformable

    OpenAIRE

    Lo Scrudato, Mirella; Blokesch, Melanie

    2013-01-01

    The human pathogen Vibrio cholerae is an aquatic bacterium associated with zooplankton and their chitinous exoskeletons. On chitinous surfaces, V. cholerae initiates a developmental programme, known as natural competence, to mediate transformation, which is a mode of horizontal gene transfer. Competence facilitates the uptake of free DNA and recombination into the bacterial genome. Recent studies have indicated that chitin surfaces are required, but not sufficient to induce competence. Two ad...

  8. Coagglutination of Vibrio cholerae, Vibrio mimicus, and Vibrio vulnificus with anti-flagellar monoclonal antibody.

    OpenAIRE

    Simonson, J G; Siebeling, R J

    1988-01-01

    Monoclonal antibodies (MAbs) with serological activity for purified flagellar (H) core protein prepared from Vibrio cholerae were identified by enzyme-linked immunosorbent assay. Four of these MAbs reacted with the flagella of V. cholerae and V. mimicus exclusively, while eight MAbs reacted with at least 1 of 30 heterologous Vibrio species tested by enzyme-linked immunosorbent assay or coagglutination. It appears that V. cholerae and V. mimicus express similar, if not identical, H determinant...

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

    Institute of Scientific and Technical Information of China (English)

    Baskar Balakrishnan; Sathish Thadikamala; Prabakaran Panchatcharam

    2014-01-01

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

  10. Characterization of Undermethylated Sites in Vibrio cholerae

    Science.gov (United States)

    Dalia, Ankur B.; Lazinski, David W.

    2013-01-01

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

  11. Surface-attachment sequence in Vibrio Cholerae

    Science.gov (United States)

    Utada, Andrew; Gibiansky, Maxsim; Wong, Gerard

    2013-03-01

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

  12. Response of Pathogenic Vibrio Species to High Hydrostatic Pressure

    OpenAIRE

    Berlin, Daniel L.; Herson, Diane S.; Hicks, Doris T.; Hoover, Dallas G.

    1999-01-01

    Vibrio parahaemolyticus ATCC 17802, Vibrio vulnificus ATCC 27562, Vibrio cholerae O:1 ATCC 14035, Vibrio cholerae non-O:1 ATCC 14547, Vibrio hollisae ATCC 33564, and Vibrio mimicus ATCC 33653 were treated with 200 to 300 MPa for 5 to 15 min at 25°C. High hydrostatic pressure inactivated all strains of pathogenic Vibrio without triggering a viable but nonculturable (VBNC) state; however, cells already existing in a VBNC state appeared to possess greater pressure resistance.

  13. Ethanolamine utilization in Vibrio alginolyticus

    Directory of Open Access Journals (Sweden)

    Khatri Neelam

    2012-12-01

    Full Text Available 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.

  14. OpaR, a Homolog of Vibrio harveyi LuxR, Controls Opacity of Vibrio parahaemolyticus

    Science.gov (United States)

    McCarter, Linda L.

    1998-01-01

    Vibrio parahaemolyticus is an organism well adapted to communal life on surfaces. When grown on a surface or in a viscous layer, the bacterium induces a large gene system and differentiates to swarmer cells capable of movement over and colonization of surfaces. V. parahaemolyticus displays additional phenotypic versatility manifested as variable colony morphology, switching between translucent and opaque colony types. Although not itself luminescent, V. parahaemolyticus produces autoinducer molecules capable of inducing luminescence in Vibrio harveyi. To examine the role of quorum signaling in the lifestyles of V. parahaemolyticus, the functional homolog of the gene encoding the V. harveyi autoinducer-controlled transcriptional regulatory protein LuxR was cloned. Sequence analysis of the clone predicted an open reading frame with a deduced product 96% identical to LuxR. Introduction of the clone carrying the luxR-like locus into V. parahaemolyticus dramatically affected colony morphology, converting a translucent strain to an opaque one. When the coding sequence for the luxR homolog was placed under the control of the Ptac promoter, conversion to the opaque phenotype became inducible by isopropyl-β-d-thiogalactopyranoside. Allelic disruption of the luxR-like gene on the chromosome of an opaque strain produced a translucent strain proficient in swarming ability. Primer extension mapping demonstrated opaR transcription in opaque but not translucent cell types. It is postulated that this gene, which has been named opaR, encodes a transcription factor controlling cell type. The underlying genetic basis for opaque-translucent variation may be the consequence of a genomic alteration detected in the opaR locus of opaque and translucent strains. PMID:9620967

  15. Environmental reservoirs and mechanisms of persistence of Vibrio cholerae

    Directory of Open Access Journals (Sweden)

    Carla eLutz

    2013-12-01

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

  16. Whole-Genome Sequence of Vibrio alginolyticus Isolated from the Mucus of the Coral Fungia danai in the Andaman Sea, India

    Science.gov (United States)

    Bhotra, Tilothama

    2016-01-01

    Vibrio alginolyticus, a halophilic Gram-negative bacterium, which is found in temperate marine and estuarine environments, is known to cause infections in humans and other organisms. We sequenced the genome of sulfamethoxazole-trimthoprim-positive V. alginolyticus strain 4-19 isolated from the mucus of the coral Fungia danai in the Andaman Sea, India. PMID:27151803

  17. Whole-Genome Sequence of Vibrio alginolyticus Isolated from the Mucus of the Coral Fungia danai in the Andaman Sea, India.

    Science.gov (United States)

    Bhotra, Tilothama; Singh, Durg V

    2016-01-01

    Vibrio alginolyticus, a halophilic Gram-negative bacterium, which is found in temperate marine and estuarine environments, is known to cause infections in humans and other organisms. We sequenced the genome of sulfamethoxazole-trimthoprim-positive V. alginolyticus strain 4-19 isolated from the mucus of the coral Fungia danai in the Andaman Sea, India. PMID:27151803

  18. Whole-Genome Sequence of Vibrio alginolyticus Isolated from the Mucus of the Coral Fungia danai in the Andaman Sea, India

    OpenAIRE

    Bhotra, Tilothama; Singh, Durg V.

    2016-01-01

    Vibrio alginolyticus, a halophilic Gram-negative bacterium, which is found in temperate marine and estuarine environments, is known to cause infections in humans and other organisms. We sequenced the genome of sulfamethoxazole-trimthoprim-positive V. alginolyticus strain 4-19 isolated from the mucus of the coral Fungia danai in the Andaman Sea, India.

  19. Sensitivity of the vibrios to ultraviolet-radiation

    International Nuclear Information System (INIS)

    The ultraviolet-inactivation kinetics of a number of strains of Vibrio cholerae (classical), Vibrio cholerae (el tor), NAG vibrios and Vibrio parahaemolyticus were investigated. Statistical analyses revealed significant differences between any two of the four types of vibrio in respect of their sensitivity to U.V. (author)

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

    OpenAIRE

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

    2013-01-01

    Photobacterium damselae subsp. damselae (formerly Vibrio damsela) is a pathogen of a variety of marine animals including fish, crustaceans, molluscs, and cetaceans. In humans, it can cause opportunistic infections that may evolve into necrotizing fasciitis with fatal outcome. Although the genetic basis of virulence in this bacterium is not completely elucidated, recent findings demonstrate that the phospholipase-D Dly (damselysin) and the pore-forming toxins HlyApl and HlyAch play a main role...

  1. VIBRIO VULNIFICUS EDUCATION WORKSHOPS / MATERIALS

    Science.gov (United States)

    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...

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

    Directory of Open Access Journals (Sweden)

    StefanPukatzki

    2013-12-01

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

  3. Colera y Vibrio cholerae Cholera and Vibrio cholerae

    OpenAIRE

    Sandra Fernandez F; Guillermina Alonso

    2009-01-01

    El Colera es una diarrea infecciosa aguda producida por Vibrio cholerae. La transmision se produce predominantemente a traves de agua o alimentos contaminados. La administracion de antibioticos puede disminuir la severidad de los sintomas. A partir de 1977, se han caracterizado cepas de V.cholerae O1 con resistencia multiple a los antibioticos. Los determinantes de resistencia han sido reportados principalmente asociados a plasmidos e integrones. Historicamente, solo las cepas del serogrupo O...

  4. Development of a Real-Time Resistance Measurement for Vibrio parahaemolyticus Detection by the Lecithin-Dependent Hemolysin Gene

    OpenAIRE

    Xiang, Guiming; Pu, Xiaoyun; Jiang, Dongneng; Liu, Linlin; Liu, Chang; Liu, Xiaobo

    2013-01-01

    The marine bacterium Vibrio parahaemolyticus (V. parahaemolyticus) causes gastroenteritis in humans via the ingestion of raw or undercooked contaminated seafood, and early diagnosis and prompt treatment are important for the prevention of V. parahaemolyticus-related diseases. In this study, a real-time resistance measurement based on loop-mediated isothermal amplification (LAMP), electrochemical ion bonding (Crystal violet and Mg2+), real-time monitoring, and derivative analysis was developed...

  5. Identification of a Wzy Polymerase Required for Group IV Capsular Polysaccharide and Lipopolysaccharide Biosynthesis in Vibrio vulnificus▿

    OpenAIRE

    Nakhamchik, Alina; Wilde, Caroline; Rowe-Magnus, Dean A.

    2007-01-01

    The estuarine bacterium Vibrio vulnificus is a human and animal pathogen. The expression of capsular polysaccharide (CPS) is essential for virulence. We used a new mini-Tn10 delivery vector, pNKTXI-SceI, to generate a mutant library and identify genes essential for CPS biosynthesis. Twenty-one acapsular mutants were isolated, and the disrupted gene in one mutant, coding for a polysaccharide polymerase (wzy), is described here. A wecA gene initiating glycosyltransferase was among the genes ide...

  6. Vibrio chromosomes share common history

    OpenAIRE

    Gevers Dirk; Chang Sarah; Chang LeeAnn; Kirkup Benjamin C; Polz Martin F

    2010-01-01

    Abstract Background While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it is an open question to what extent the two chromosomes themselves share a common history since their formation. Results Single copy genes from each chromosome (142 genes from chromosome I and 42 genes from chromosome II) were identified from 19 sequenced Vibrionales genomes ...

  7. NAD metabolism in Vibrio cholerae.

    OpenAIRE

    Foster, J. W.; Brestel, C

    1982-01-01

    Extracts of Vibrio cholerae were assayed for various enzymatic activities associated with pyridine nucleotide cycle metabolism. The activities measured include NAD glycohydrolase, nicotinamide deamidase, nicotinamide mononucleotide deamidase, and nicotinic acid phosphoribosyltransferase. The results obtained demonstrate the existence in V. cholerae of the five-membered pyridine nucleotide cycle and the potential for a four-membered pyridine nucleotide cycle. The data presented also suggest th...

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

    Science.gov (United States)

    Barron, Addie; Hagen, Steve; Son, Minjun

    2015-03-01

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

  9. Repair of ultraviolet-light-induced DNA damage in Vibrio cholerae

    International Nuclear Information System (INIS)

    Repair of ultraviolet-light-induced DNA damage in a highly pathogenic Gram-negative bacterium, Vibrio cholerae, has been examined. All three strains of V. cholerae belonging to two serotypes, Inaba and Ogawa, are very sensitive to ultraviolet irradiation, having inactivation cross-sections ranging from 0.18 to 0.24 m2/J. Although these cells are proficient in repairing the DNA damage by a photoreactivation mechanism, they do not possess efficient dark repair systems. The mild toxinogenic strain 154 of classical Vibrios presumably lacks any excision repair mechanism and studies of irradiated cell DNA indicate that the ultraviolet-induced pyrimidine dimers may not be excised. Ultraviolet-irradiated cells after saturation of dark repair can be further photoreactivated. (Auth.)

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

    Science.gov (United States)

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

    2013-04-19

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

  11. Studies on the pathogenic bacterium of ulcer disease in Epinephelus awoara

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Studies were conducted to determine the cause of the acute mortality of cage-cultured Epinephelus awoara in the Tong'an Bay of Xiamen, China during the summer of 2002. Predominant bacteria strain TS-628 was isolated from the diseased grouper. The virulence test confirmed that TS-628 was the pathogenic bacterium. Biochemical characteristics of the isolates were determined using the automatic bacterial identification system and standard tube tests. To further confirm the identification, a 1 121 bp 16S rRNA gene sequence of the isolate was amplified by PCR, which had been deposited into Genbank (accession number: AY747308). According to the biochemical characteristics and by comparing the 16S rRNA gene homology of the isolate, the pathogenic bacterium was identified as Vibrio harveyi. Drug sensitivity tests showed that this pathogenic bacterium was sensitive to 16 antibacterials, especially to chloramphenicol and actinospectacin, but completely resistant to antibacterials likes vancomycin, penicillin, lincomycin, and so on.

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

    Directory of Open Access Journals (Sweden)

    Vengadesh eLetchumanan

    2015-01-01

    Full Text Available 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 Vibrio 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 thermostable direct hemolysin (tdh in the disease pathogenesis. This study aimed to investigate the antimicrobial resistance Vibrio 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 TDH-related hemolysin (trh gene and none of the isolates were tested positive for thermostable direct hemolysin (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-sulfamet (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.

  13. Natural plasmid transformation in a high-frequency-of-transformation marine Vibrio strain.

    OpenAIRE

    Frischer, M E; Thurmond, J M; Paul, J. H.

    1990-01-01

    The estuarine bacterium Vibrio strain DI-9 has been shown to be naturally transformable with both broad host range plasmid multimers and homologous chromosomal DNA at average frequencies of 3.5 X 10(-9) and 3.4 X 10(-7) transformants per recipient, respectively. Growth of plasmid transformants in nonselective medium resulted in cured strains that transformed 6 to 42, 857 times more frequently than the parental strain, depending on the type of transforming DNA. These high-frequency-of-transfor...

  14. Complete Genome Sequence of Vibrio parahaemolyticus Bacteriophage vB_VpaM_MAR

    OpenAIRE

    Alanis Villa, Argentina; Kropinski, Andrew M.; Abbasifar, Reza; Griffiths, Mansel W.

    2012-01-01

    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 th...

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

    Science.gov (United States)

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

    2009-12-01

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

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

    International Nuclear Information System (INIS)

    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

  17. Hydrolysis of Fish Oil by Olive Oil-Induced Vibrio sp. Lipase

    OpenAIRE

    ANDO, Seiichi; アンドウ, セイイチ; 安藤, 清一

    1991-01-01

    A potent marine bacterium of genus Vibrio for lipase production was isolatedfrom the red tides and tentatively named VB-5.The strain VB-5 showed the optimal production of lipase when cultivated at 20°Cfor 48 hr in a medium composed of casitone, proteose peptone, yeast extract, naturalseawater and olive oil. The lipase activity from the strain VB-5 was enhanced byadding 0.33% olive oil to the medium. The olive oil-induced lipase had an optimalpH of 10 for activity at 25°C. The lipase hydrolyze...

  18. Hydrolysis of Fish Oil by Olive Oil-Induced Vibrio sp. Lipase

    OpenAIRE

    ANDO, Seiichi; アンドウ, セイイチ; 安藤, 清一

    1991-01-01

    A potent marine bacterium of genus Vibrio for lipase production was isolated from the red tides and tentatively named VB-5. The strain VB-5 showed the optimal production of lipase when cultivated at 20°C for 48 hr in a medium composed of casitone, proteose peptone, yeast extract, natural seawater and olive oil. The lipase activity from the strain VB-5 was enhanced by adding 0.33% olive oil to the medium. The olive oil-induced lipase had an optimal pH of 10 for activity at 25...

  19. Swedish isolates of Vibrio cholerae enhance their survival when interacted intracellularly with Acanthamoeba castellanii

    OpenAIRE

    Shanan, Salah; Bayoumi, Magdi; Saeed, Amir; Sandström, Gunnar; Abd, Hadi

    2016-01-01

    Vibrio cholerae is a Gram-negative bacterium that occurs naturally in aquatic environment. Only V. cholerae O1 and V. cholerae O139 produce cholera toxin and cause cholera, other serogroups can cause gastroenteritis, open wounds infection, and septicaemia. V. cholerae O1 and V. cholerae O139 grow and survive inside Acanthamoeba castellanii. The aim of this study is to investigate the interactions of the Swedish clinical isolates V. cholerae O3, V. cholerae O4, V. cholerae O5, V. cholerae O11,...

  20. Dethiosulfovibrio peptidovorans gen. nov., sp. nov., a new anaerobic, slightly halophilic, thiosulfate-reducing bacterium from corroding offshore oil wells

    OpenAIRE

    Magot, M; Ravot, G; Campaignolle, X.; Ollivier, Bernard; Patel, B.K.C.; Fardeau, Marie-Laure; Thomas, P; Crolet, J.L.; Garcia, Jean-Louis

    1997-01-01

    A strictly anaerobic thiosulfate-reducing bacterium was isolated from a corroding offshore oil well in Congo and was designated strain SEBR 4207(T). Pure culture of the strain induced a very active pitting corrosion of mild steel, with penetration rates of up to 4 mm per year. This constitutes the first experimental evidence of the involvement of thiosulfate reduction in microbial corrosion of steel. Strain SEBR 4207(T) cells were vibrios (3 to 5 by 1 micrometer), stained gram negative, and p...

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

    Directory of Open Access Journals (Sweden)

    AllisonNNorsworthy

    2013-11-01

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

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

    Science.gov (United States)

    Henke, Jennifer M.; Bassler, Bonnie L.

    2004-01-01

    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

  3. Genome engineering in Vibrio cholerae

    DEFF Research Database (Denmark)

    Val, Marie-Eve; Skovgaard, Ole; Ducos-Galand, Magaly;

    2012-01-01

    Although bacteria with multipartite genomes are prevalent, our knowledge of the mechanisms maintaining their genome is very limited, and much remains to be learned about the structural and functional interrelationships of multiple chromosomes. Owing to its bi-chromosomal genome architecture and its...... importance in public health, Vibrio cholerae, the causative agent of cholera, has become a preferred model to study bacteria with multipartite genomes. However, most in vivo studies in V. cholerae have been hampered by its genome architecture, as it is difficult to give phenotypes to a specific chromosome....... This difficulty was surmounted using a unique and powerful strategy based on massive rearrangement of prokaryotic genomes. We developed a site-specific recombination-based engineering tool, which allows targeted, oriented, and reciprocal DNA exchanges. Using this genetic tool, we obtained a panel of V...

  4. Vibrio chromosomes share common history

    Directory of Open Access Journals (Sweden)

    Gevers Dirk

    2010-05-01

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

  5. Genome engineering in Vibrio cholerae

    DEFF Research Database (Denmark)

    Val, Marie-Eve; Skovgaard, Ole; Ducos-Galand, Magaly;

    2012-01-01

    Although bacteria with multipartite genomes are prevalent, our knowledge of the mechanisms maintaining their genome is very limited, and much remains to be learned about the structural and functional interrelationships of multiple chromosomes. Owing to its bi-chromosomal genome architecture and its...... importance in public health, Vibrio cholerae, the causative agent of cholera, has become a preferred model to study bacteria with multipartite genomes. However, most in vivo studies in V. cholerae have been hampered by its genome architecture, as it is difficult to give phenotypes to a specific chromosome....... This difficulty was surmounted using a unique and powerful strategy based on massive rearrangement of prokaryotic genomes. We developed a site-specific recombination-based engineering tool, which allows targeted, oriented, and reciprocal DNA exchanges. Using this genetic tool, we obtained a panel of V. cholerae...

  6. Resistance to Antimicrobial Peptides in Vibrios

    Directory of Open Access Journals (Sweden)

    Delphine Destoumieux-Garzón

    2014-10-01

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

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

    OpenAIRE

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

    2014-01-01

    Despite major attempts to prevent cholera transmission, millions of people worldwide still must address this devastating disease. Cholera research has so far mainly focused on the causative agent, the bacterium Vibrio cholerae, or on disease treatment, but rarely were results from both fields interconnected. Indeed, the treatment of this severe diarrheal disease is mostly accomplished by oral rehydration therapy (ORT), whereby water and electrolytes are replenished. Commonly distributed oral ...

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

    Science.gov (United States)

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

    2015-11-01

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

  9. Vibrios associated with red tides caused by Mesodinium rubrum.

    OpenAIRE

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

    1990-01-01

    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. Cytotoxic...

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

    Science.gov (United States)

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

    2014-01-01

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

  11. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vibrio cholerae serological reagents. 866.3930... cholerae serological reagents. (a) Identification. Vibrio cholerae serological reagents are devices that are used in the agglutination (an antigen-antibody clumping reaction) test to identify Vibrio...

  12. The pathogenesis, detection and prevention of Vibrio parahaemolyticus

    Directory of Open Access Journals (Sweden)

    Rongzhi eWang

    2015-03-01

    Full Text Available Vibrio parahaemolyticus, a Gram-negative motile bacterium that inhabits marine and estuarine environments throughout the world, is a major food-borne pathogen that causes life-threatening diseases in humans after the consumption of raw or undercooked seafood. The global occurrence of V. parahaemaolyticus accentuates the importance of investigating its virulence factors and their effects on the human host. This review describes the virulence factors of V. parahaemolyticus reported to date, including hemolysin, urease, two type III secretion systems (T3SS and two type VI secretion systems (T6SS, which both cause both cytotoxicity in cultured cells and enterotoxicity in animal models. We describe various types of detection methods, based on virulence factors, that are used for quantitative detection of V. parahaemolyticus in seafood. We also discuss some useful preventive measures and therapeutic strategies for the diseases mediated by V. parahaemolyticus, which can reduce, to some extent, the damage to humans and aquatic animals attributable to V. parahaemolyticus. This review extends our understanding of the pathogenic mechanisms of V. parahaemolyticus mediated by virulence factors and the diseases it causes in its human host. It should provide new insights for the diagnosis, treatment, and prevention of V. parahaemolyticus infection.

  13. Genomic evidence of adaptive evolution in emergent Vibrio parahaemolyticus ecotypes

    Directory of Open Access Journals (Sweden)

    Jeffrey W. Turner

    2016-07-01

    Full Text Available Abstract The ubiquitous marine bacterium Vibrio parahaemolyticus is a leading cause of illness associated with seafood consumption. The emergence of two genetically distinct ecotypes (ST3 and ST36 has led to an alarming increase in the size and frequency of disease outbreaks. We conducted a genomic comparison of 30 V. parahaemolyticus genomes that represent a diverse collection of 15 genetically distinct ecotypes, including newly sequenced representatives of ST3 and ST36, isolated from both clinical and environmental sources. A multistep evolutionary analysis showed that genes associated with sensing and responding to environmental stimuli have evolved under positive selection, identifying examples of convergent evolution between ST3 and ST36. A comparison of predicted proteomes indicated that ST3 and ST36 ecotypes laterally acquired tens of novel genes associated with a variety of functions including dormancy, homeostasis and membrane transport. Genes identified in this study play an apparent role in environmental fitness and may confer cross protection against stressors encountered in the human host. Together, these results show the evolution of stress response is an important genetic mechanism correlated with the recent emergence of the ST3 and ST36 ecotypes.

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

    Science.gov (United States)

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

    2010-03-01

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

  15. Quorum Sensing in the Squid-Vibrio Symbiosis

    Directory of Open Access Journals (Sweden)

    Tim Miyashiro

    2013-08-01

    Full Text Available Quorum sensing is an intercellular form of communication that bacteria use to coordinate group behaviors such as biofilm formation and the production of antibiotics and virulence factors. The term quorum sensing was originally coined to describe the mechanism underlying the onset of luminescence production in cultures of the marine bacterium Vibrio fischeri. Luminescence and, more generally, quorum sensing are important for V. fischeri to form a mutualistic symbiosis with the Hawaiian bobtail squid, Euprymna scolopes. The symbiosis is established when V. fischeri cells migrate via flagella-based motility from the surrounding seawater into a specialized structure injuvenile squid called the light organ. The cells grow to high cell densities within the light organ where the infection persists over the lifetime of the animal. A hallmark of a successful symbiosis is the luminescence produced by V. fischeri that camouflages the squid at night by eliminating its shadow within the water column. While the regulatory networks governing quorum sensing are critical for properly regulating V. fischeri luminescence within the squid light organ, they also regulate luminescence-independent processes during symbiosis. In this review, we discuss the quorum-sensing network of V. fischeri and highlight its impact at various stages during host colonization.

  16. The two chromosomes of Vibrio cholerae are initiated at different time points in the cell cycle

    DEFF Research Database (Denmark)

    Rasmussen, Tue; Jensen, Rasmus Bugge; Skovgaard, Ole

    2007-01-01

    The bacterium Vibrio cholerae, the cause of the diarrhoeal disease cholera, has its genome divided between two chromosomes, a feature uncommon for bacteria. The two chromosomes are of different sizes and different initiator molecules control their replication independently. Using novel methods for...... approximately the same time and the average number of replication origins per cell is higher for chromosome I than for chromosome II. Analysis of cell-cycle parameters shows that chromosome replication and segregation is exceptionally fast in V. cholerae. The divided genome and delayed replication of chromosome...

  17. Pathogenicity of Vibrios in Fish: an Overview

    Institute of Scientific and Technical Information of China (English)

    LI Jun; Norman Y.S. Woo

    2003-01-01

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

  18. Biosynthetic Pathways of Vibrio succinogenes growing with fumarate as terminal electron acceptor and sole carbon source.

    Science.gov (United States)

    Bronder, M; Mell, H; Stupperich, E; Kröger, A

    1982-05-01

    1. With fumarate as the terminal electron acceptor and either H2 or formate as donor, Vibrio succinogenes could grow anaerobically in a mineral medium using fumarate as the sole carbon source. Both the growth rate and the cell yield were increased when glutamate was also present in the medium. 2. Glutamate was incorporated only into the amino acids of the glutamate family (glutamate, glutamine, proline and arginine) of the protein. The residual cell constituents were synthesized from fumarate. 3. Pyruvate and phosphoenolpyruvate, as the central intermediates of most of the cell constituents, were formed through the action of malic enzyme and phosphoenolpyruvate synthetase. Fructose-1,6-bisphosphate aldolase was present in the bacterium suggesting that this enzyme is involved in carbohydrate synthesis. 4. In the absence of added glutamate the amino acids of the glutamate family were synthesized from fumarate via citrate. The enzymes involved in glutamate synthesis were present. 5. During growth in the presence of glutamate, net reducing equivalents were needed for cell synthesis. Glutamate and not H2 or formate was used as the source of these reducing equivalents. For this purpose part of the glutamate was oxidized to yield succinate and CO2. 6. The alpha-ketoglutarate dehydrogenase involved in this reaction was found to use ferredoxin as the electron acceptor. The ferredoxin of the bacterium was reoxidized by means of a NADP-ferredoxin oxidoreductase. Enzymes catalyzing the reduction of NAD, NADP or ferredoxin by H2 or formate were not detected in the bacterium. PMID:7103660

  19. Vibrio ecology - Identifying Environmental Determinants Favorable for the Presence and Transmission of Pathogenic Vibrios

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In a tri-coastal collaborative study, the population densities of vibrios are being determined in the Mississippi Sound, Puget Sound, Chesapeake Bay, and Timbalier...

  20. Quorum Sensing-Disrupting Brominated Furanones Protect the Gnotobiotic Brine Shrimp Artemia franciscana from Pathogenic Vibrio harveyi, Vibrio campbellii, and Vibrio parahaemolyticus Isolates†

    OpenAIRE

    Defoirdt, Tom; Crab, Roselien; Wood, Thomas K.; Sorgeloos, Patrick; Verstraete, Willy; Bossier, Peter

    2006-01-01

    Autoinducer 2 (AI-2) quorum sensing was shown before to regulate the virulence of Vibrio harveyi towards the brine shrimp Artemia franciscana. In this study, several different pathogenic V. harveyi, Vibrio campbellii, and Vibrio parahaemolyticus isolates were shown to produce AI-2. Furthermore, disruption of AI-2 quorum sensing by a natural and a synthetic brominated furanone protected gnotobiotic Artemia from the pathogenic isolates in in vivo challenge tests.

  1. Quorum Sensing-Disrupting Brominated Furanones Protect the Gnotobiotic Brine Shrimp Artemia franciscana from Pathogenic Vibrio harveyi, Vibrio campbellii, and Vibrio parahaemolyticus Isolates†

    Science.gov (United States)

    Defoirdt, Tom; Crab, Roselien; Wood, Thomas K.; Sorgeloos, Patrick; Verstraete, Willy; Bossier, Peter

    2006-01-01

    Autoinducer 2 (AI-2) quorum sensing was shown before to regulate the virulence of Vibrio harveyi towards the brine shrimp Artemia franciscana. In this study, several different pathogenic V. harveyi, Vibrio campbellii, and Vibrio parahaemolyticus isolates were shown to produce AI-2. Furthermore, disruption of AI-2 quorum sensing by a natural and a synthetic brominated furanone protected gnotobiotic Artemia from the pathogenic isolates in in vivo challenge tests. PMID:16957276

  2. Vibrio-Infektionen durch Lebensmittel und Meerwasser. Das Netzwerk VibrioNet stellt sich vor

    OpenAIRE

    Alter, T.; Appel, Bernd; Bartelt, E.; Dieckmann, Ralf; Eichhorn, C.; Erler, R.; Frank, Christina; Gerdts, G.; Gunzer, Florian; Hühn, S.; Neifer, Janina; Oberheitmann, B.; Strauch, Eckhard

    2011-01-01

    Vibrionen sind salzliebende Bakterien, die in Oberflächen- und Küstengewässern sowie Meerestieren weltweit verbreitet sind. In vielen Ländern stellen pathogene Vibrio-Spezies eine der Hauptursachen von bakteriell verursachten Durchfallerkrankungen dar, die durch den Verzehr von kontaminierten Meeresfrüchten und Fischprodukten und durch verseuchtes Trinkwasser hervorgerufen werden. Vibrio-Infektionen könnten auch in unseren Breiten aufgrund der globalen Klimaerwärmung und der Zunahme des weltw...

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

    OpenAIRE

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

    2015-01-01

    Vibrio parahaemolyticus and Vibrio cholerae are ubiquitous to estuarine and marine environments. These two species found in Mediterranean coastal systems can induce infections in humans. Environmental isolates of V. cholerae (n = 109) and V. parahaemolyticus (n = 89) sampled at different dates, stations and water salinities were investigated for virulence genes and by a multilocus sequence-based analysis (MLSA). V. cholerae isolates were all ctxA negative and only one isolate of V. parahaemol...

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

    OpenAIRE

    Takeda, Yoshifumi

    2011-01-01

    This review highlighted the following: (i) pathogenic mechanism of the thermostable direct hemolysin produced by Vibrio parahaemolyticus, especially on its cardiotoxicity, (ii) heat-labile and heat-stable enterotoxins produced by enterotoxigenic Escherichia coli, especially 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) ...

  5. Lactococcus lactis - a diploid bacterium

    DEFF Research Database (Denmark)

    Michelsen, Ole; Hansen, Flemming G.; Jensen, Peter Ruhdal

    In contrast to higher eukaryotes, bacteria are haploid, i.e. they store their genetic information in a single chromosome, which is then duplicated during the cell cycle. If the growth rate is sufficiently low, the bacterium is born with only a single copy of the chromosome, which gets duplicated...... before the bacterium divides. Fast-growing bacteria have overlapping rounds of replication, and can contain DNA corresponding to more than four genome equivalents. However, the terminus region of the chromosome is still present in just one copy after division, and is not duplicated until right before...... the next division. Thus, the regions of the chromosome that are the last to be replicated are haploid even in fast-growing bacteria. In contrast to this general rule for bacteria, we found that Lactococcus lactis, a bacterium which has been exploited for thousands of years for the production of fermented...

  6. Single Bacterium Detection Using Sers

    Science.gov (United States)

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

    2016-02-01

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

  7. EFFECT OF AGGREGATION ON VIBRIO CHOLERAE INACTIVATION

    Science.gov (United States)

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

  8. Adhesion of Vibrio cholerae to Granular Starches

    OpenAIRE

    Gancz, Hanan; Niderman-Meyer, Orly; Broza, Meir; Kashi, Yechezkel; Shimoni, Eyal

    2005-01-01

    Cholera is a severe diarrheal disease caused by specific serogroups of Vibrio cholerae that are pathogenic to humans. Cholera can become epidemic and deadly without adequate medical care. Appropriate rehydration therapy can reduce the mortality rate from as much as 50% of the affected individuals to

  9. Vibrio cholerae bacteremia associated with gastrectomy.

    OpenAIRE

    Toeg, A; Berger, S A; Battat, A; Hoffman, M.; Yust, I

    1990-01-01

    Bacteremia due to Vibrio cholerae is rare. Each of 15 cases previously reported in the English language literature occurred in the setting of immune deficiency. We describe an instance of non-serogroup O1 V. cholerae septicemia in an otherwise healthy patient. Susceptibility to such infection may have been enhanced by a prior gastrectomy for duodenal ulcer.

  10. Vibrio cholerae O1 isolated in Kenya.

    OpenAIRE

    Iwanaga, M; Mori, K.; Kaviti, J N

    1982-01-01

    Biological and serological analyses of 272 isolates of Vibrio cholerae O1 from six epidemics and from a few sporadic cases in Kenya were carried out. All of the isolates were identified as V. cholerae biotype E1 Tor, and 210 out of 272 isolates were hemolytic as examined by Feeley's method.

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

    Science.gov (United States)

    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...

  12. Inhibition of Vibrio anguillarum by Pseudomonas fluorescens AH2, a possible probiotic treatment of fish

    DEFF Research Database (Denmark)

    Gram, Lone; Melchiorsen, Jette; Spanggaard, Bettina; Huber, I.; Nielsen, T.F.

    1999-01-01

    To study the possible use of probiotics in fish farming, we evaluated the in vitro and in vivo antagonism of antibacterial strain Pseudomonas fluorescens strain AH2 against the fish- pathogenic bacterium Vibrio anguillarum. As iron is important in virulence and bacterial interactions, the effect of....... fluorescens AH2 inhibited the growth of V. anguillarum during coculture, independently of the iron concentration, when the initial count of the antagonist was 100 to 1,000 times greater that of the fish pathogen. These in vitro results were successfully repeated in vivo. A probiotic effect in vivo was tested...... probiotic treatment resulted in a 46% reduction of calculated accumulated mortality; accumulated mortality was 25% after 7 days at 12 degrees C in the probiotic-treated fish, whereas mortality was 47% in fish not treated with the probiont...

  13. Inhibition of Vibrio anguillarum by Pseudomonas fluorescens AH2, a possible probiotic treatment of fish

    DEFF Research Database (Denmark)

    Gram, Lone; Melchiorsen, Jette; Spanggaard, Bettina;

    1999-01-01

    To study the possible use of probiotics in fish farming, we evaluated the in vitro and in vivo antagonism of antibacterial strain Pseudomonas fluorescens strain AH2 against the fish- pathogenic bacterium Vibrio anguillarum. As iron is important in virulence and bacterial interactions, the effect of...... P.fluorescens AH2 was studied under iron-rich and iron-limited conditions. Sterile-filtered culture supernatants from iron- limited P. fluorescens AH2 inhibited the growth of V. anguillarum, whereas sterile-filtered supernatants from iron- replete cultures of P. fluorescens AH2 did not. P....... fluorescens AH2 inhibited the growth of V. anguillarum during coculture, independently of the iron concentration, when the initial count of the antagonist was 100 to 1,000 times greater that of the fish pathogen. These in vitro results were successfully repeated in vivo. A probiotic effect in vivo was tested...

  14. Genetically Modified Vibrio harveyi Strains as Potential Bioindicators of Mutagenic Pollution of Marine Environments

    Science.gov (United States)

    Czyż, Agata; Jasiecki, Jacek; Bogdan, Adam; Szpilewska, Hanna; Węgrzyn, Grzegorz

    2000-01-01

    For biodetection of mutagenic pollution of marine environments, an organism naturally occurring in these habitats should be used. We found that marine bacterium Vibrio harveyi may be an appropriate bioindicator of mutagenic pollution. For positive selection of mutants, we developed a simple method for isolation of V. harveyi mutants resistant to neomycin. We constructed genetically modified V. harveyi strains that produce significantly more neomycin-resistant mutants upon treatment with low concentrations of mutagens than the wild-type counterpart. The sensitivity of the mutagenicity test with the V. harveyi strains is at least comparable to (if not higher than) that of the commonly used Ames test, which uses Salmonella enterica serovar Typhimurium strains. Therefore, we consider that the V. harveyi strains described in this report could be used as potential bioindicators of mutagenic pollution of marine environments. PMID:10653723

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

    Science.gov (United States)

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

    2011-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-02-01

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

  17. Vibrio harveyi quorum sensing: a coincidence detector for two autoinducers controls gene expression

    Science.gov (United States)

    Mok, Kenny C.; Wingreen, Ned S.; Bassler, Bonnie L.

    2003-01-01

    In a process called quorum sensing, bacteria communicate with one another by exchanging chemical signals called autoinducers. In the bioluminescent marine bacterium Vibrio harveyi, two different auto inducers (AI-1 and AI-2) regulate light emission. Detection of and response to the V.harveyi autoinducers are accomplished through two two-component sensory relay systems: AI-1 is detected by the sensor LuxN and AI-2 by LuxPQ. Here we further define the V.harveyi quorum-sensing regulon by identifying 10 new quorum-sensing-controlled target genes. Our examination of signal processing and integration in the V.harveyi quorum-sensing circuit suggests that AI-1 and AI-2 act synergistically, and that the V.harveyi quorum-sensing circuit may function exclusively as a ‘coincidence detector’ that discriminates between conditions in which both autoinducers are present and all other conditions. PMID:12574123

  18. Isolation and characterization of Pseudoalteromonas sp. from fermented Korean food, as an antagonist to Vibrio harveyi.

    Science.gov (United States)

    Morya, V K; Choi, Wooyoung; Kim, Eun-Ki

    2014-02-01

    The microbial intervention for sustainable management of aquaculture, especially use of probiotics, is one of the most popular and practical approaches towards controlling pathogens. Vibrio harveyi is a well-known pathogenic bacterium, which is associated to a huge economic loss in the aquaculture system by causing vibriosis. The present study is crafted for screening and characterization of anti-Vibrio strains, which were isolated from various traditional fermented Korean foods. A total of 196 strains have been isolated from soybean paste (78 strains), red chili paste (49 strains), soy sauce (18 strains), jeotgal-a salted fish (34 strains), and the gazami crab-Portunus trituberculatus (17 strains). Fifteen strains showed an inhibitory effect on the growth of V. harveyi when subjected to coculture condition. Among the strains isolated, one has been identified as a significant anti-Vibrio strain. Further biochemical characterization and 16S rDNA sequencing revealed it as Pseudoalteromonas aliena, which had been deposited at the Korean Culture Center of Microorganisms (KCCM), Korea and designated as KCCM 11207P. The culture supernatants did not have any antimicrobial properties either in pure or in coculture condition. The culture supernatant was not toxic when supplemented to the swimming crab, Zoea, and Artemia larvae in aquaculture system. The results were very encouraging and showed a significant reduction in accumulated mortality. Here, we reported that pathogenic vibriosis can be controlled by Pseudoalteromonas sp. under in vitro and in vivo conditions. The results indicated that the biotic treatment offers a promising alternative to the use of antibiotics in crab aquaculture. PMID:23793257

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

    Science.gov (United States)

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

    2013-08-01

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

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

    Science.gov (United States)

    Tu, Kimberly C.; Bassler, Bonnie L.

    2007-01-01

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

  1. Broad spectrum pro-quorum-sensing molecules as inhibitors of virulence in vibrios.

    Science.gov (United States)

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

    2012-01-01

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

  2. Broad spectrum pro-quorum-sensing molecules as inhibitors of virulence in vibrios.

    Directory of Open Access Journals (Sweden)

    Wai-Leung Ng

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

  3. Isolation and characterization of Vibrio ( Listonella) anguillarum from catfish

    OpenAIRE

    Rad, Mehrnaz; Shahsavani, Davar

    2010-01-01

    Vibrio anguillarum was isolated from several organs of some aquarium catfish in a fish population with high mortality. Macroscopic examination of the affected catfish revealed ascites in the abdomen, site-petechiae, and dorsal erection. Although there are some variations in phenotypic characterization among different isolates of Vibrio anguillarum, the majority show a common biochemical profile with distinct microscopic appearance that can provide presumptive identification of Vibrio anguilla...

  4. Phylogeny of Vibrio cholerae Based on recA Sequence

    OpenAIRE

    Stine, O. Colin; Sozhamannan, Shanmuga; Gou, Qing; Zheng, Siqen; Morris, J. Glenn; Johnson, Judith A.

    2000-01-01

    We sequenced a 705-bp fragment of the recA gene from 113 Vibrio cholerae strains and closely related species. One hundred eighty-seven nucleotides were phylogenetically informative, 55 were phylogenetically uninformative, and 463 were invariant. Not unexpectedly, Vibrio parahaemolyticus and Vibrio vulnificus strains formed out-groups; we also identified isolates which resembled V. cholerae biochemically but which did not cluster with V. cholerae. In many instances, V. cholerae serogroup desig...

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

    Science.gov (United States)

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

    2015-01-01

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

  6. Vibrio cholerae Infection of Drosophilamelanogaster Mimics the Human Disease Cholera.

    Directory of Open Access Journals (Sweden)

    2005-09-01

    Full Text Available Cholera, the pandemic diarrheal disease caused by the gram-negative bacterium Vibrio cholerae, continues to be a major public health challenge in the developing world. Cholera toxin, which is responsible for the voluminous stools of cholera, causes constitutive activation of adenylyl cyclase, resulting in the export of ions into the intestinal lumen. Environmental studies have demonstrated a close association between V. cholerae and many species of arthropods including insects. Here we report the susceptibility of the fruit fly, Drosophila melanogaster, to oral V. cholerae infection through a process that exhibits many of the hallmarks of human disease: (i death of the fly is dependent on the presence of cholera toxin and is preceded by rapid weight loss; (ii flies harboring mutant alleles of either adenylyl cyclase, Gsalpha, or the Gardos K channel homolog SK are resistant to V. cholerae infection; and (iii ingestion of a K channel blocker along with V. cholerae protects wild-type flies against death. In mammals, ingestion of as little as 25 mug of cholera toxin results in massive diarrhea. In contrast, we found that ingestion of cholera toxin was not lethal to the fly. However, when cholera toxin was co-administered with a pathogenic strain of V. cholerae carrying a chromosomal deletion of the genes encoding cholera toxin, death of the fly ensued. These findings suggest that additional virulence factors are required for intoxication of the fly that may not be essential for intoxication of mammals. Furthermore, we demonstrate for the first time the mechanism of action of cholera toxin in a whole organism and the utility of D. melanogaster as an accurate, inexpensive model for elucidation of host susceptibility to cholera.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-01-01

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

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

    OpenAIRE

    Barbieri, Elena; Falzano, Loredana; Fiorentini, Carla; Pianetti, Anna; Baffone, Wally; Fabbri, Alessia; Matarrese, Paola; Casiere, Annarita; Katouli, Mohammad; Kühn, Inger; Möllby, Roland; Bruscolini, Francesca; Donelli, Gianfranco

    1999-01-01

    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 causing cytoskeleton-dependent changes was detected in a large num...

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

    Science.gov (United States)

    Slock, James

    1995-01-01

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

  10. Genetic analysis of Vibrio parahaemolyticus intestinal colonization.

    Science.gov (United States)

    Hubbard, Troy P; Chao, Michael C; Abel, Sören; Blondel, Carlos J; Abel Zur Wiesch, Pia; Zhou, Xiaohui; Davis, Brigid M; Waldor, Matthew K

    2016-05-31

    Vibrio parahaemolyticus is the most common cause of seafood-borne gastroenteritis worldwide and a blight on global aquaculture. This organism requires a horizontally acquired type III secretion system (T3SS2) to infect the small intestine, but knowledge of additional factors that underlie V. parahaemolyticus pathogenicity is limited. We used transposon-insertion sequencing to screen for genes that contribute to viability of V. parahaemolyticus in vitro and in the mammalian intestine. Our analysis enumerated and controlled for the host infection bottleneck, enabling robust assessment of genetic contributions to in vivo fitness. We identified genes that contribute to V. parahaemolyticus colonization of the intestine independent of known virulence mechanisms in addition to uncharacterized components of T3SS2. Our study revealed that toxR, an ancestral locus in Vibrio species, is required for V. parahaemolyticus fitness in vivo and for induction of T3SS2 gene expression. The regulatory mechanism by which V. parahaemolyticus ToxR activates expression of T3SS2 resembles Vibrio cholerae ToxR regulation of distinct virulence elements acquired via lateral gene transfer. Thus, disparate horizontally acquired virulence systems have been placed under the control of this ancestral transcription factor across independently evolved human pathogens. PMID:27185914

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

    OpenAIRE

    Spira, W M; Fedorka-Cray, P. J.

    1983-01-01

    We have examined the effect of complete cell recycle on the production of cholera toxin (CT) by Vibrio cholerae and CT-like toxin by Vibrio mimicus in continuous culture fermentations. Complete cell recycle was obtained by filtering culture fluids through Amicon hollow fibers with an exclusion limit of 100,000 daltons (H1P100-20) and returning the concentrated cell slurry to the fermentor. A single 1-liter laboratory fermentor system modified with this recycle loop was capable of producing ov...

  12. A VIBRIO ANGUILLARUM STRAIN ASSOCIATED WITH SKIN ULCER ON CULTURED FLOUNDER, PARALICHTHYS OLIVACEUS

    Institute of Scientific and Technical Information of China (English)

    莫照兰; 谭训刚; 徐永立; 张培军

    2001-01-01

    The characteristics of a bacterium strain M3, isolated from cultured flounder Paralichthys olivaceus with remarkable external sign of skin ulcer during an epizootic outbreak, indicated that the bacterium belonged to the species Vibrio anguillarum. Challenge by I.M. ( intramuscular injection), bath, and oral administration with M3 showed that it was highly pathogenic for Paralichthys olivacues. The LD50 dose was 5. 144 × 103 CFU/per fish infection by I.M. injection. Recovered inoculated bacteria from the surviving fish revealed that the asymptomatic carriers could be a latent contagious source. Study of the effect of bacterial culture CFS (cell-free-supernatant) showed that the exotoxins produced by M3 play an important role in its pathogenicity for flounder. The resistance of M3 to 36 out of 41 antibiotics indicated that the bacterial disease outbreak was mainly attributable to the frequent and excessive use of antimicrobial agents; and that vaccination would be an effective precaution against bacterial disease.

  13. A VIBRIO ANGUILIARUM STRAIN ASSOCIATED WITH SKIN ULCER ON CULTURED FLOUNDER, PARALICHTHYS OLIVACEUS

    Institute of Scientific and Technical Information of China (English)

    莫照兰; 谭训刚; 徐永立; 张培军

    2001-01-01

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

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

    Science.gov (United States)

    Montánchez, Itxaso; Arana, Inés; Parada, Claudia; Garaizabal, Idoia; Orruño, Maite; Barcina, Isabel; Kaberdin, Vladimir R

    2014-01-01

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

  15. Collagenolytic activity of Vibrio vulnificus: potential contribution to its invasiveness.

    OpenAIRE

    Smith, G.C.; Merkel, J R

    1982-01-01

    Vibrio vulnificus (lactose-positive vibrio) produced collagenase when grown in 2% synthetic sea salts supplemented with hydrolyzed casein. The addition of collagen or peptone to the medium increased the level of collagenase production. Collagenase activity was inhibited by EDTA but not by fetal calf serum.

  16. Vibrio cholerae O139 in Thailand in 1994.

    OpenAIRE

    Bodhidatta, L.; Echeverria, P; Hoge, C W; Pitarangsi, C; Serichantalergs, O; Henprasert-Tae, N.; Harikul, S.; Kitpoka, P.

    1995-01-01

    Vibrio cholerae O139 first appeared in India and Bangladesh in 1992. Surveillance for O139 was started at three hospitals in Thailand in 1993. By 1994 all three hospitals surveyed in Thailand had experienced an increase in Vibrio cholerae O139 infections.

  17. Vibrio cholerae non-serogroup O1 cystitis.

    OpenAIRE

    Dumler, J.S.; Osterhout, G J; Spangler, J G; Dick, J D

    1989-01-01

    We report a case of a patient who developed cystitis caused by non-serogroup O1 Vibrio cholerae after swimming in the Chesapeake Bay. Treatment was empirical, with complete symptomatic resolution. Genitourinary tract infections by Vibrio spp. are uncommon but should be considered when cystitis occurs after saltwater exposure in appropriate geographic regions.

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

    Science.gov (United States)

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

    2016-03-15

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

  19. Selectivity of Vibrio cholerae H-NOX for Gaseous Ligands Follows “Sliding Scale Rule” Hypothesis: Ligand Interactions with both Ferrous and Ferric Vc H-NOX

    OpenAIRE

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

    2013-01-01

    Vc H-NOX (or VCA0720) is an H-NOX (heme-nitric oxide and oxygen binding) protein from facultative aerobic bacterium Vibrio cholerae. It shares significant sequence homology with soluble guanylyl cyclase (sGC), a NO sensor protein commonly found in animals. Similar to sGC, Vc H-NOX binds strongly to NO and CO with affinities of 0.27 nM and 0.77 μM, respectively, but weakly to O2. When positioned in “sliding scale” plot {Tsai, A.-L. et. al. (2012) Biochemistry, 51, pp172-86}, the line connectin...

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

    Science.gov (United States)

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

    2000-01-01

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

  1. Survey on antimicrobial resistance patterns in Vibrio vulnificus and Vibrio cholerae non-O1/non-O139 in Germany reveals carbapenemase-producing Vibrio cholerae in coastal waters

    OpenAIRE

    Bier, Nadja; Schwartz, Keike; Guerra, Beatriz; Strauch, Eckhard

    2015-01-01

    An increase in the occurrence of potentially pathogenic Vibrio species is expected for waters in Northern Europe as a consequence of global warming. In this context, a higher incidence of Vibrio infections is predicted for the future and forecasts suggest that people visiting and living at the Baltic Sea are at particular risk. This study aimed to investigate antimicrobial resistance patterns among Vibrio vulnificus and Vibrio cholerae non-O1/non-O139 isolates that could pose a public health ...

  2. The Role of Vibrios in Diseases of Corals.

    Science.gov (United States)

    Munn, Colin B

    2015-08-01

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

  3. Vibrio elicits targeted transcriptional responses from copepod hosts.

    Science.gov (United States)

    Almada, Amalia A; Tarrant, Ann M

    2016-06-01

    Copepods are abundant crustaceans that harbor diverse bacterial communities, yet the nature of their interactions with microbiota are poorly understood. Here, we report that Vibrio elicits targeted transcriptional responses in the estuarine copepod Eurytemora affinis We pre-treated E. affinis with an antibiotic cocktail and exposed them to either a zooplankton specialist (Vibrio sp. F10 9ZB36) or a free-living species (Vibrio ordalii 12B09) for 24 h. We then identified via RNA-Seq a total of 78 genes that were differentially expressed following Vibrio exposure, including homologs of C-type lectins, chitin-binding proteins and saposins. The response differed between the two Vibrio treatments, with the greatest changes elicited upon inoculation with V. sp. F10 We suggest that these differentially regulated genes play important roles in cuticle integrity, the innate immune response, and general stress response, and that their expression may enable E. affinis to recognize and regulate symbiotic vibrios. We further report that V. sp. F10 culturability is specifically altered upon colonization of E. affinis These findings suggest that rather than acting as passive environmental vectors, copepods discriminately interact with vibrios, which may ultimately impact the abundance and activity of copepod-associated bacteria. PMID:27056917

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

    Science.gov (United States)

    Shao, Chung-Ping; Hor, Lien-I

    2001-01-01

    Expression of the Vibrio vulnificus metalloprotease gene, vvp, was turned up rapidly when bacterial growth reached the late log phase. A similar pattern of expression has been found in the metalloprotease gene of Vibrio cholerae, and this has been shown to be regulated by a Vibrio harveyi LuxR-like transcriptional activator. To find out whether a LuxR homologue exists in V. vulnificus, a gene library of this organism was screened by colony hybridization using a probe derived from a sequence that is conserved in various luxR-like genes of vibrios. A gene containing a 618-bp open reading frame was identified and found to be identical to the smcR gene of V. vulnificus reported previously. An isogenic SmcR-deficient (RD) mutant was further constructed by an in vivo allelic exchange technique. This mutant exhibited an extremely low level of vvp transcription compared with that of the parent strain. On the other hand, the cytolysin gene, vvhA, was expressed at a higher level in the RD mutant than in the parent strain during the log phase of growth. These data suggested that SmcR might not only be a positive regulator of the protease gene but might also be involved in negative regulation of the cytolysin gene. Virulence of the RD mutant in either normal or iron-overloaded mice challenged by intraperitoneal injection was comparable to that of the parent strain, indicating that SmcR is not required for V. vulnificus virulence in mice. PMID:11157950

  5. Natural plasmid transformation in a high-frequency-of transformation marine Vibrio strain

    International Nuclear Information System (INIS)

    The estuarine bacterium Vibrio strain DI-9 has been shown to be naturally transformable with both broad host range plasmid multimers and homologous chromosomal DNA at average frequencies of 3.5 x 10-9 and 3.4 x 10-7 transformants per recipient, respectively. Growth of plasmid transformants in nonselective medium resulted in cured strains that transformed 6 to 42,857 times more frequently than the parental strain, depending on the type of transforming DNA. These high-frequency-of-transformation (HfT) strains were transformed at frequencies ranging from 1.1 x 10-8 to 1.3 x 10-4 transformants per recipient with plasmid DNA and at an average frequency of 8.3 x 10-5 transformants per recipient with homologous chromosomal DNA. The highest transformation frequencies were observed by using multimers of an R1162 derivative carrying the transposon Tn5 (pQSR50). Probing of total DNA preparations from one of the cured strains demonstrated that no plasmid DNA remained in the cured strains which may have provided homology to the transforming DNA. All transformants and cured strains could be differentiated from the parental strains by colony morphology. DNA binding studies indicated that late-log-phase HfT strains bound [3H]bacteriophage lambda DNA 2.1 times more rapidly than the parental strain. These results suggest that the original plasmid transformation event of strain DI-9 was the result of uptake and expression of plasmid DNA by a competent mutant (HfT strain). Additionally, it was found that a strain of Vibrio parahaemolyticus, USFS 3420, could be naturally transformed with plasmid DNA. Natural plasmid transformation by high-transforming mutants may be a means of plasmid acquisition by natural aquatic bacterial populations

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

    Science.gov (United States)

    Tiruvayipati, Suma; Bhassu, Subha; Kumar, Narender; Baddam, Ramani; Shaik, Sabiha; Gurindapalli, Anil Kumar; Thong, Kwai Lin; Ahmed, Niyaz

    2013-01-01

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

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

    Science.gov (United States)

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

    2007-07-01

    Growth of Vibrio cholerae O1 Ogawa Eltor was studied with a growth assay in which autoclaved and filtered (0.22 microm) freshwater was inoculated at low cell density (5 x 10(3) cells ml(-1)) and proliferation was followed with flow cytometry. Against the common view, V. cholerae was able to grow extensively in different kinds of freshwater. The bacterium multiplied in river water, lake water and effluent of a wastewater treatment plant up to a cell density of 1.55 x 10(6) cells ml(-1). In these samples, apparent assimilable organic carbon (AOC(app)) concentrations ranged from 52 up to 800 microg l(-1) and the results demonstrate a positive trend between the AOC(app) concentration and final cell concentration, suggesting that AOC was a key parameter governing growth of V. cholerae. No growth was observed in waters (tap and bottled drinking water) containing less than approximately 60 microg AOC(app) l(-1). When pure cultures of V. cholerae were grown on identical lake water at different temperatures (20, 25 and 30 degrees C) the maximum specific growth rates (micromax) achieved were 0.22 h(-1), 0.32 h(-1) and 0.45 h(-1), respectively. In addition, growth was characterized in lake water samples amended with different concentrations of NaCl. The highest micromax of V. cholerae was recorded at moderate salinity levels (5 g NaCl l(-1), micromax=0.84 h(-1)), whereas at 30 g NaCl l(-1) (micromax=0.30 h(-1)) or 0 g NaCl l(-1) (micromax)=0.40 h(-1)) specific growth rates were significantly reduced. In the water tested here, micro(max) of V. cholerae was always around 50 % of that exhibited by a freshwater community of indigenous bacteria enriched from the water sampling site. Direct batch competition experiments between V. cholerae and the lake water bacterial community were performed at different temperatures in which V. cholerae was enumerated in the total community using fluorescent-surface antibodies. In all cases V. cholerae was able to grow and constituted around 10

  8. Antibiotic resistance of Vibrio parahaemolyticus and Vibrio vulnificus in various countries: A review.

    Science.gov (United States)

    Elmahdi, Sara; DaSilva, Ligia V; Parveen, Salina

    2016-08-01

    Vibrio parahaemolyticus and Vibrio vulnificus are the leading causes of seafood associated infections and mortality in the United States. The main syndromes caused by these pathogens are gastroenteritis, wound infections, and septicemia. This article reviewed the antibiotic resistance profile of V. parahaemolyticus and V. vulnificus in the United States and other countries including Italy, Brazil, Philippines, Malaysia, Thailand, China, India, Iran, South Africa and Australia. The awareness of antimicrobial resistance of these two pathogens is not as well documented as other foodborne bacterial pathogens. Vibrio spp. are usually susceptible to most antimicrobials of veterinary and human significance. However, many studies reported that V. vulnificus and V. parahaemolyticus showed multiple-antibiotic resistance due to misuse of antibiotics to control infections in aquaculture production. In addition, both environmental and clinical isolates showed similar antibiotic resistance profiles. Most frequently observed antibiotic resistance profiles involved ampicillin, penicillin and tetracycline regardless of the countries. The presence of multiple-antibiotic resistant bacteria in seafood and aquatic environments is a major concern in fish and shellfish farming and human health. PMID:27052711

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

    Science.gov (United States)

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

    2013-02-01

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

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

    Science.gov (United States)

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

    2013-01-01

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

  11. 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.

    Science.gov (United States)

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

    2013-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-03-04

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Yueming Xu

    2013-08-01

    Full Text Available 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.

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

    Science.gov (United States)

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

    2013-01-01

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

  16. Enhancement of enterotoxin production by carbon dioxide in Vibrio cholerae.

    OpenAIRE

    Shimamura, T; Watanabe, S; Sasaki, S.

    1985-01-01

    We found that Vibrio cholerae 569B produced much more cholera enterotoxin in the presence of added carbon dioxide than in its absence. An atmosphere of 10% carbon dioxide was optimal for maximal enterotoxin production.

  17. Spatiotemporal Dynamics of Vibrio spp. within the Sydney Harbour Estuary

    Science.gov (United States)

    Siboni, Nachshon; Balaraju, Varunan; Carney, Richard; Labbate, Maurizio; Seymour, Justin R.

    2016-01-01

    Vibrio are a genus of marine bacteria that have substantial environmental and human health importance, and there is evidence that their impact may be increasing as a consequence of changing environmental conditions. We investigated the abundance and composition of the Vibrio community within the Sydney Harbour estuary, one of the most densely populated coastal areas in Australia, and a region currently experiencing rapidly changing environmental conditions. Using quantitative PCR (qPCR) and Vibrio-specific 16S rRNA amplicon sequencing approaches we observed significant spatial and seasonal variation in the abundance and composition of the Vibrio community. Total Vibrio spp. abundance, derived from qPCR analysis, was higher during the late summer than winter and within locations with mid-range salinity (5–26 ppt). In addition we targeted three clinically important pathogens: Vibrio cholerae, V. Vulnificus, and V. parahaemolyticus. While toxigenic strains of V. cholerae were not detected in any samples, non-toxigenic strains were detected in 71% of samples, spanning a salinity range of 0–37 ppt and were observed during both late summer and winter. In contrast, pathogenic V. vulnificus was only detected in 14% of samples, with its occurrence restricted to the late summer and a salinity range of 5–26 ppt. V. parahaemolyticus was not observed at any site or time point. A Vibrio-specific 16S rRNA amplicon sequencing approach revealed clear shifts in Vibrio community composition across sites and between seasons, with several Vibrio operational taxonomic units (OTUs) displaying marked spatial patterns and seasonal trends. Shifts in the composition of the Vibrio community between seasons were primarily driven by changes in temperature, salinity and NO2, while a range of factors including pH, salinity, dissolved oxygen (DO) and NOx (Nitrogen Oxides) explained the observed spatial variation. Our evidence for the presence of a spatiotemporally dynamic Vibrio community

  18. Temporal and Spatial Distribution Patterns of Potentially Pathogenic Vibrio spp. at Recreational Beaches of the German North Sea

    OpenAIRE

    Böer, S.; Heinemeyer, E.A.; Luden, K.; Erler, Rene; Gerdts, Gunnar; Janssen, Frank; Brennholt, Nicole

    2013-01-01

    The number of reported Vibrio-related wound infections associated with recreational bathing in Northern Europe has increased within the last decades. In order to study the health risk from potentially pathogenic Vibrio spp. in the central Wadden Sea, the seasonal and spatial distribution of Vibrio vulnificus, Vibrio parahaemolyticus, Vibrio alginolyticus and Vibrio cholerae were investigated at ten recreational beaches in this area over a 2-year period. V. alginolyticus and V. parahaemolyt...

  19. Inactivation of Vibrio anguillarum by Attached and Planktonic Roseobacter Cells▿

    OpenAIRE

    D'Alvise, Paul W.; Melchiorsen, Jette; Porsby, Cisse H.; Nielsen, Kristian F.; Gram, Lone

    2010-01-01

    The purpose of the present study was to investigate the inhibition of Vibrio by Roseobacter in a combined liquid-surface system. Exposure of Vibrio anguillarum to surface-attached roseobacters (107 CFU/cm2) resulted in significant reduction or complete killing of the pathogen inoculated at 102 to 104 CFU/ml. The effect was likely associated with the production of tropodithietic acid (TDA), as a TDA-negative mutant did not affect survival or growth of V. anguillarum.

  20. Inactivation of Vibrio anguillarum by attached and planktonic Roseobacter cells

    DEFF Research Database (Denmark)

    D'Alvise, Paul; Melchiorsen, Jette; Porsby, Cisse Hedegaard;

    2010-01-01

    The purpose of the present study was to investigate inhibition of Vibrio by Roseobacter in a combined liquid-surface system. Exposure of Vibrio anguillarum to surface-attached roseobacters (10e7 cfu/cm2) resulted in significant reduction or complete killing of the pathogen inoculated at 10e2 – 10...... cfu/ml. The effect was likely associated with production of tropodithietic acid (TDA), as a TDA-negative mutant did not affect survival or growth of V. anguillarum....

  1. Extracellular proteolytic enzymes produced by human pathogenic vibrio species

    OpenAIRE

    Miyoshi, Shin-Ichi

    2013-01-01

    Bacteria in the genus Vibrio produce extracellular proteolytic enzymes to obtain nutrients via digestion of various protein substrates. However, the enzymes secreted by human pathogenic species have been documented to modulate the bacterial virulence. Several species including Vibrio cholerae and V. vulnificus are known to produce thermolysin-like metalloproteases termed vibriolysin. The vibriolysin from V. vulnificus, a causative agent of serious systemic infection, is a major toxic factor e...

  2. Passive Immune-Protection of Litopenaeus vannamei against Vibrio harveyi and Vibrio parahaemolyticus Infections with Anti-Vibrio Egg Yolk (IgY)-Encapsulated Feed.

    Science.gov (United States)

    Gao, Xiaojian; Zhang, Xiaojun; Lin, Li; Yao, Dongrui; Sun, Jingjing; Du, Xuedi; Li, Xiumei; Zhang, Yue

    2016-01-01

    Vibrio spp. are major causes of mortality in white shrimp (Litopenaeus vannamei) which is lacking adaptive immunity. Passive immunization with a specific egg yolk antibody (IgY) is a potential method for the protection of shrimp against vibriosis. In this study, immune effects of the specific egg yolk powders (IgY) against both V. harveyi and V. parahaemolyticus on white shrimp were evaluated. The egg yolk powders against V. harveyi and V. parahaemolyticus for passive immunization of white shrimp were prepared, while a tube agglutination assay and an indirect enzyme-linked immunosorbent assay (ELISA) were used for detection of IgY titer. Anti-Vibrio egg yolk was encapsulated by β-cyclodextrin, which could keep the activity of the antibody in the gastrointestinal tract of shrimp. The results showed that the anti-Vibrio egg powders had an inhibiting effect on V. harveyi and V. parahaemolyticus in vitro. Lower mortality of infected zoeae, mysis, and postlarva was observed in groups fed with anti-Vibrio egg powders, compared with those fed with normal egg powders. The bacterial load in postlarva fed with specific egg powders in seeding ponds was significantly lower than those fed with normal egg powders in seeding ponds. These results show that passive immunization by oral administration with specific egg yolk powders (IgY) may provide a valuable protection of vibrio infections in white shrimp. PMID:27196895

  3. Passive Immune-Protection of Litopenaeus vannamei against Vibrio harveyi and Vibrio parahaemolyticus Infections with Anti-Vibrio Egg Yolk (IgY-Encapsulated Feed

    Directory of Open Access Journals (Sweden)

    Xiaojian Gao

    2016-05-01

    Full Text Available Vibrio spp. are major causes of mortality in white shrimp (Litopenaeus vannamei which is lacking adaptive immunity. Passive immunization with a specific egg yolk antibody (IgY is a potential method for the protection of shrimp against vibriosis. In this study, immune effects of the specific egg yolk powders (IgY against both V. harveyi and V. parahaemolyticus on white shrimp were evaluated. The egg yolk powders against V. harveyi and V. parahaemolyticus for passive immunization of white shrimp were prepared, while a tube agglutination assay and an indirect enzyme-linked immunosorbent assay (ELISA were used for detection of IgY titer. Anti-Vibrio egg yolk was encapsulated by β-cyclodextrin, which could keep the activity of the antibody in the gastrointestinal tract of shrimp. The results showed that the anti-Vibrio egg powders had an inhibiting effect on V. harveyi and V. parahaemolyticus in vitro. Lower mortality of infected zoeae, mysis, and postlarva was observed in groups fed with anti-Vibrio egg powders, compared with those fed with normal egg powders. The bacterial load in postlarva fed with specific egg powders in seeding ponds was significantly lower than those fed with normal egg powders in seeding ponds. These results show that passive immunization by oral administration with specific egg yolk powders (IgY may provide a valuable protection of vibrio infections in white shrimp.

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

    Science.gov (United States)

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

    2014-01-01

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

  5. Vibrio cholerae Biofilms and Cholera Pathogenesis.

    Directory of Open Access Journals (Sweden)

    Anisia J Silva

    2016-02-01

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

  6. Comparative microscopy study of Vibrio cholerae flagella

    Science.gov (United States)

    Konnov, Nikolai P.; Baiburin, Vil B.; Zadnova, Svetlana P.; Volkov, Uryi P.

    1999-06-01

    A fine structure of bacteria flagella is an important problem of molecular cell biology. Bacteria flagella are the self-assembled structures that allow to use the flagellum protein in a number of biotechnological applications. However, at present, there is a little information about high resolution scanning probe microscopy study of flagellum structure, in particular, about investigation of Vibrio cholerae flagella. In our lab have been carried out the high resolution comparative investigation of V. cholerae flagella by means of various microscopes: tunneling (STM), scanning force (SFM) and electron transmission. As a scanning probe microscope is used designed in our lab versatile SPM with replaceable measuring heads. Bacteria were grown, fixed and treated according to the conventional techniques. For STM investigations samples were covered with Pt/Ir thin films by rotated vacuum evaporation, in SFM investigations were used uncovered samples. Electron microscopy of the negatively stained bacteria was used as a test procedure.

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

    Directory of Open Access Journals (Sweden)

    Amable J. Rivas

    2013-09-01

    Full Text Available 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 P. 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.

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

    Science.gov (United States)

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

    2013-01-01

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

  9. Spatiotemporal dynamics of Vibrio spp. within the Sydney Harbour estuary

    Directory of Open Access Journals (Sweden)

    Nachshon eSiboni

    2016-04-01

    Full Text Available Vibrio are a genus of marine bacteria that have substantial environmental and human health importance, and there is evidence that their impact may be increasing as a consequence of changing environmental conditions. We investigated the abundance and composition of the Vibrio community within the Sydney Harbour estuary, one of the most densely populated coastal areas in Australia, and a region currently experiencing rapidly changing environmental conditions. Using Quantitative PCR (qPCR and vibrio-specific 16S rRNA amplicon sequencing approaches we observed significant spatial and seasonal variation in the abundance and composition of the Vibrio community. Total Vibrio spp. abundance, derived from qPCR analysis, was higher during the late summer than winter and within locations with mid-range salinity (5-26 ppt. In addition we targeted three clinically important pathogens: V. cholerae, V. vulnificus and V. parahaemolyticus. While toxigenic strains of V. cholerae were not detected in any samples, non-toxigenic strains were detected in 71% of samples, spanning a salinity range of 0-37 ppt and were observed during both late summer and winter. In contrast, pathogenic V. vulnificus was only detected in 14% of samples, with its occurrence restricted to the late summer and a salinity range of 5-26 ppt. V. parahaemolyticus was not observed at any site or time point. A vibrio-specific 16S rRNA amplicon sequencing approach revealed clear shifts in Vibrio community composition across sites and between seasons, with several Vibrio Operational Taxonomic Units (OTUs displaying marked spatial patterns and seasonal trends. Shifts in the composition of the Vibrio community between seasons were primarily driven by changes in temperature, salinity and NO2, while a range of factors including pH, salinity, Dissolved Oxygen (DO and NOx (Nitrogen Oxides explained the observed spatial variation. Our evidence for the presence of a spatiotemporally dynamic Vibrio

  10. Liquid holding recovery and photoreactivation of the ultraviolet-inactivated vibrios

    International Nuclear Information System (INIS)

    The kinetics of liquid holding recovery and photoreactivation of the ultra-violet-inactivated vibrios have been investigated. Photoreactivation was highest (about 80%) for Vibrio cholerae (classical) strains but the liquid holding recovery was highest (about 29%) for Vibrio parahemolyticus ones. Significance of the differences between any two of the four vibrio biotypes in respect of their liquid holding recovery and also photoreactivation was analysed statistically. (auth.)

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

    Directory of Open Access Journals (Sweden)

    Labbate Maurizio

    2011-11-01

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

  12. Draft Genome Sequence of Hawaiian Sea Slug Symbiont Vibrio sp. Strain ER1A

    OpenAIRE

    Davis, Jeanette; Hill, Russell T.

    2014-01-01

    Bacteria belonging to the genus Vibrio are prevalent in the marine environment and are known for forming symbiotic relationships with hosts. Vibrio sp. strain ER1A is a dominant symbiont of the Hawaiian sea slug, Elysia rufescens. Here we report the draft genome sequence of Vibrio sp. ER1A.

  13. Observing Chemotaxis in Vibrio fischeri Using Soft Agar Assays in an Undergraduate Microbiology Laboratory

    Directory of Open Access Journals (Sweden)

    Cindy R. DeLoney-Marino

    2013-08-01

    Full Text Available Chemotaxis, the directed movement of cells towards or away from a chemical, is both an exciting and complicated behavior observed in many bacterial species. Attempting to adequately visualize or demonstrate the chemotaxic response of bacteria in the classroom is difficult at best, with good models to illustrate the concept lacking. The BSL-1 marine bacterium Vibrio fischeri (a.k.a. Aliivibrio fischeri is easy to culture, making it an ideal candidate for experiments in an undergraduate microbiology course. A number of chemoattractants for V. fischeri have been identified, including a variety of sugars, nucleosides, and amino acids (1, 2. Below presents how the soft agar-based chemotaxis assay can be implemented in the undergraduate laboratory. As bacterial cells migrate towards one or more attractants in soft agar, students can directly observe the chemotaxic behavior of V. fischeri without the need to learn complicated techniques or use specialized equipment. Once the bands of bacterial cells are observed, the migration can then be disrupted by the addition of excess attractant to the soft agar, thereby visualizing what happens once cells are no longer in a gradient of attractant. In addition, soft agar plates lacking attractants can be used to visualize the random movements of bacterial cells that are non-chemotaxing. These exercises can be used in the microbiology laboratory to help students understand the complex behavior of bacterial chemotaxis.

  14. Reduction of acute toxicity of the pharmaceutical fluoxetine (Prozac) submitted to ionizing radiation to Vibrio fischeri

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Dymes R.A.; Garcia, Vanessa S.G.; Vilarrubia, Anna C.S.; Borrely, Sueli I., E-mail: vanessagarcia@usp.br, E-mail: sborrely@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The constant use of pharmaceutical drugs by great part of the population and its continuous input into the environment creates a growing need of investigating its presence, behavior and the effects on aquatic biota, as well as new ways to treat wastewater containing such substances. The fluoxetine hydrochloride (FH) present in the drug Prozac is an active ingredient used in the treatment of depressive and anxiety disorders. Generally, these compounds enter the aquatic environment by sewage collectors systems after undergoing prior treatment in sewage treatment plants (STPs) or without any treatment. This study focused on evaluating the reduction of acute toxicity of the pharmaceutical FH, under its manipulated formula, for the marine bacterium Vibrio fischeri. It was also evaluated the acute toxicity of the aqueous solution containing the FH after its exposition to ionizing radiation from industrial electron accelerator. It was performed acute toxicity tests lasting 15 minutes, where the average EC (50) of the non-irradiated CF water solution was approximately 0.68 mg L-1. While the CF water solution irradiated with 1 kGy, 2.5 kGy, 7.5 kGy and 10 kGy, presented an average EC(50) 1.63 mg.L{sup -1}, 2.34 mg.L{sup -1}, 2.35 mg.L{sup -1} and 1.80 mg.L{sup -1}, respectively, showing a notable reduction of the acute toxicity for this organism. (author)

  15. Swedish isolates of Vibrio cholerae enhance their survival when interacted intracellularly with Acanthamoeba castellanii

    Directory of Open Access Journals (Sweden)

    Salah Shanan

    2016-04-01

    Full Text Available Vibrio cholerae is a Gram-negative bacterium that occurs naturally in aquatic environment. Only V. cholerae O1 and V. cholerae O139 produce cholera toxin and cause cholera, other serogroups can cause gastroenteritis, open wounds infection, and septicaemia. V. cholerae O1 and V. cholerae O139 grow and survive inside Acanthamoeba castellanii. The aim of this study is to investigate the interactions of the Swedish clinical isolates V. cholerae O3, V. cholerae O4, V. cholerae O5, V. cholerae O11, and V. cholerae O160 with A. castellanii. The interaction between A. castellanii and V. cholerae strains was studied by means of amoeba cell counts, viable counts of the bacteria in the absence or presence of amoebae, and of the intracellularly growing bacteria, visualised by electron microscopy. These results show that all V. cholerae can grow and survive outside and inside the amoebae, disclosing that V. cholerae O3, V. cholerae O4, V. cholerae O5, V. cholerae O11, and V. cholerae O160 all can be considered as facultative intracellular bacteria.

  16. Characterization of Vibrio Parahaemolyticus isolated from oysters and mussels in São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Martha Virginia Ribeiro Rojas

    2011-08-01

    Full Text Available Vibrio parahaemolyticus is a marine bacterium, responsible for gastroenteritis in humans. Most of the clinical isolates produce thermostable direct hemolysin (TDH and TDH-related hemolysin (TRH encoded by tdh and trh genes respectively. In this study, twenty-three V. parahaemolyticus, previously isolated from oysters and mussels were analyzed by PCR using specific primers for the 16S rRNA and virulence genes (tdh, trh and tlh and for resistance to different classes of antibiotics and PFGE. Nineteen isolates were confirmed by PCR as V. parahaemolyticus. The tlh gene was present in 100% of isolates, the tdh gene was identified in two (10.5% isolates, whereas the gene trh was not detected. Each isolate was resistant to at least one of the nine antimicrobials tested. Additionally, all isolates possessed the blaTEM-116 gene. The presence of this gene in V. parahaemolyticus indicates the possibility of spreading this gene in the environment. Atypical strains of V. parahaemolyticus were also detected in this study.

  17. Prevalence and distribution of Vibrio parahaemolyticus in finfish from Cochin (south India

    Directory of Open Access Journals (Sweden)

    Ammanamveetil A.M. Hatha

    2012-09-01

    Full Text Available Finfish samples obtained from four retail outlets in Cochin between June 2009 and June 2010 were investigated for the occurrence of Vibrio parahaemolyticus. A total of 182 samples were collected and suspect isolates were identified using standard biochemical tests and were further confirmed by a species-specific tlh gene. V. parahaemolyticus was detected in 45.1% of samples, with demersal fish being more affected than pelagic species. The bacterium was isolated more frequently from the skin and gills of pelagic fish, while the intestine yielded greater numbers of V. parahaemolyticus in demersal fish. The highest incidence of antibiotic resistance was recorded against ampicillin and streptomycin, followed by carbenicillin, cefpodoxime, cephalothin, colistin and amoxycillin; the lowest was against nalidixic acid, tetracycline, chloramphenicol and ciprofloxacin. Multiple drug resistance was prevalent among isolates. Although only a fraction of strains are pathogenic for humans, the time-temperature abuse in markets provides ample scope for these strains to multiply to dangerous levels. The multidrug resistant nature of the strains adds to the gravity of the problem. High V. parahaemolyticus incidence rates in market finfish samples from areas in and around Cochin clearly indicates that control measures should be adopted to reduce post-harvest contamination in seafood and time-temperature abuse in markets to diminish the risk of V. parahaemolyticus infection associated with seafood destined for human consumption.

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

    Science.gov (United States)

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

    2015-01-01

    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

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

    Science.gov (United States)

    Waters, Christopher M.; Bassler, Bonnie L.

    2006-01-01

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

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

    Science.gov (United States)

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

    2008-01-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2015-06-01

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

  3. Assessment of heavy metals bioavailability and toxicity toward Vibrio fischeri in sediment of the Huelva estuary.

    Science.gov (United States)

    Rosado, Daniel; Usero, José; Morillo, José

    2016-06-01

    Relationship between toxicity and bioavailable metals in sediments from the Huelva estuary and its littoral of influence was analyzed. Toxicity was assessed with Microtox(®) bioassay using a marine luminescent bacterium: Vibrio fischeri. Bioavailable metals were considered as both, acid extractable fraction of BCR procedure and the sum of exchangeable and bound to carbonates fractions of Tessier sequential extraction. A bioavailable metals index was calculated to integrate results in a single figure. Toxicity and bioavailable metals showed a similar pattern. Higher levels were found in the estuary than in the littoral (140 TU/g). In Huelva estuary, highest levels were found in the Tinto estuary (5725 TU/g), followed by the Odiel estuary (5100 TU/g) and the Padre Santo Canal (2500 TU/g). Results in this area were well over than those in nearby estuaries. Furthermore, they are similar to or even higher than those in other polluted sediments around the world. Bioavailable metal index showed a stronger correlation with acid extractable fraction of BCR (R(2) = 0.704) than that for the sum of exchangeable and bound to carbonates fractions of Tessier (R(2) = 0.661). These results suggest that bioavailable metals are an important source of sediment toxicity in the Huelva estuary and its littoral of influence, an area with one of the highest mortality risks of Spain. PMID:27002282

  4. Reduction of acute toxicity of the pharmaceutical fluoxetine (Prozac) submitted to ionizing radiation to Vibrio fischeri

    International Nuclear Information System (INIS)

    The constant use of pharmaceutical drugs by great part of the population and its continuous input into the environment creates a growing need of investigating its presence, behavior and the effects on aquatic biota, as well as new ways to treat wastewater containing such substances. The fluoxetine hydrochloride (FH) present in the drug Prozac is an active ingredient used in the treatment of depressive and anxiety disorders. Generally, these compounds enter the aquatic environment by sewage collectors systems after undergoing prior treatment in sewage treatment plants (STPs) or without any treatment. This study focused on evaluating the reduction of acute toxicity of the pharmaceutical FH, under its manipulated formula, for the marine bacterium Vibrio fischeri. It was also evaluated the acute toxicity of the aqueous solution containing the FH after its exposition to ionizing radiation from industrial electron accelerator. It was performed acute toxicity tests lasting 15 minutes, where the average EC (50) of the non-irradiated CF water solution was approximately 0.68 mg L-1. While the CF water solution irradiated with 1 kGy, 2.5 kGy, 7.5 kGy and 10 kGy, presented an average EC(50) 1.63 mg.L-1, 2.34 mg.L-1, 2.35 mg.L-1 and 1.80 mg.L-1, respectively, showing a notable reduction of the acute toxicity for this organism. (author)

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

    Directory of Open Access Journals (Sweden)

    JesusLRomalde

    2014-01-01

    Full Text Available 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 (MLSA or fluorescent amplified fragment length polymorphism (FAFLP. 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.

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

    Science.gov (United States)

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

    2014-01-01

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

  7. Quorum sensing-disrupting brominated furanones protect the gnotobiotic brine shrimp Artemia franciscana from pathogenic Vibrio harveyi, Vibrio campbellii, and Vibrio parahaemolyticus isolates

    OpenAIRE

    Defoirdt, T; Crab, R.; Wood, T. K.; Sorgeloos, P.; Verstraete, W; P. Bossier

    2006-01-01

    Autoinducer 2 (AI-2) quorum sensing was shown before to regulate the virulence of Vibrio harveyi towards the brine shrimp Artemia franciscana. In this study, several different pathogenic V. harveyi, Vibrio campbellii, and Vibrio parahaemolyticus isolates were shown to produce AI-2. Furthermore, disruption of AI-2 quorum sensing by a natural and a synthetic brominated furanone protected gnotobiotic Artemia from the pathogenic isolates in in vivo challenge tests.

  8. IDENTIFICATION OF THE BACTERIUM TOMATO STEM CANKER

    Directory of Open Access Journals (Sweden)

    Goner A. Shaker

    2014-01-01

    Full Text Available Diseased tomato samples were collected from green house was evaluated for isolation, pathogenicity and biochemical tests. The symptoms of the infected tomato plants were as sudden wilting after curled on leaves and necrotic streak regions developed at the crown and base of the stem and the cavities deepen and expand up and down, brown discoloration and necrosis occurring on xylem and phloem vasculer. All of ages of tomato plant were susceptible to bacteria when the weather condition favorable and immediately, seen collapse symptom on tomato plant at once fail and die. The bacterium was isolated from diseased plant in all regions on nutrient Agar; a yellow bacterium was isolated from infected tomato plant in green houses and fields in Abu-Ghraib, Rashiedia and Qanat Al-Geiaysh nurseries in Baghdad provinces of Iraq. The bacterium was found gram positive, rod-shaped, non-motile and capable an aerobic growth and based on the morphological and biochemical characteristics revealed that this bacterium belongs to: Clavibacter michiganensis subsp. michiganensis. (smith pathogenicity and hypersensitivity of the bacterium Cmm showed the disease index were 18.33, 6.66, 16.66, 5, 0% for tomato seedlings were inoculated treatments as the wounding roots, without wounding roots, crown of the stem, petiole and control respectively.

  9. 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

    OpenAIRE

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

    1997-01-01

    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 1...

  10. Insights into Bacteriophage Application in Controlling Vibrio Species

    Science.gov (United States)

    Letchumanan, Vengadesh; Chan, Kok-Gan; Pusparajah, Priyia; Saokaew, Surasak; Duangjai, Acharaporn; Goh, Bey-Hing; Ab Mutalib, Nurul-Syakima; Lee, Learn-Han

    2016-01-01

    Bacterial infections from various organisms including Vibrio sp. pose a serious hazard to humans in many forms from clinical infection to affecting the yield of agriculture and aquaculture via infection of livestock. Vibrio sp. is one of the main foodborne pathogens causing human infection and is also a common cause of losses in the aquaculture industry. Prophylactic and therapeutic usage of antibiotics has become the mainstay of managing this problem, however, this in turn led to the emergence of multidrug resistant strains of bacteria in the environment; which has raised awareness of the critical need for alternative non-antibiotic based methods of preventing and treating bacterial infections. Bacteriophages – viruses that infect and result in the death of bacteria – are currently of great interest as a highly viable alternative to antibiotics. This article provides an insight into bacteriophage application in controlling Vibrio species as well underlining the advantages and drawbacks of phage therapy. PMID:27486446

  11. A selective and differential medium for Vibrio harveyi.

    Science.gov (United States)

    Harris, L; Owens, L; Smith, S

    1996-01-01

    A new medium, termed Vibrio harveyi agar, has been developed for the isolation and enumeration of V. harveyi. It is possible to differentiate V. harveyi colonies from the colonies of strains representing 15 other Vibrio species with this medium. This medium has been shown to inhibit the growth of two strains of marine Pseudomonas spp. and two strains of marine Flavobacterium spp. but to allow the growth of Photobacterium strains. Colonies displaying typical V. harveyi morphology were isolated from the larval rearing water of a commercial prawn hatchery with V. harveyi agar as a primary isolation medium and were positively identified, by conventional tests, as V. harveyi. This agar displays great potential as a primary isolation medium and offers significant advantages over thiosulfate-citrate-bile salts-sucrose agar as a medium for differentiating V. harveyi from other marine and estuarine Vibrio species. PMID:8795252

  12. Cell-associated hemagglutinin-deficient mutant of Vibrio cholerae.

    OpenAIRE

    Finn, T M; Reiser, J; Germanier, R.; Cryz, S J

    1987-01-01

    Cell-associated hemagglutinin-negative mutants were derived from cholera enterotoxin-negative Vibrio cholerae JBK70 by Tn5 mutagenesis. One of the mutants identified, SB001, was characterized in greater detail. Its ability to colonize ilea of adult rabbits was determined by feeding approximately 10(8) V. cholerae to each animal. At 17 h after feeding, the numbers of viable vibrios in the ilea were determined. There was a significant, 4 log, decrease in the ability of the hemagglutinin-negativ...

  13. Long-term effects of ocean warming on vibrios

    Science.gov (United States)

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

    2012-12-01

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

  14. Resistencia a antibioticos y presencia de plasmidos en: Aeromonas hydrophila, Vibrio fluvialis y Vibrio furnissii, aislados de Carassius auratus auratus

    OpenAIRE

    Pilar Negrete Redondo; Jorge Romero Jarero; José Luis Arredondo Figueroa

    2004-01-01

    Se aislaron e identificaron 70 cepas bacterianas del riñón de peces de ornato Carassius auratus con signos y lesiones de infección. Las especies bacterianas aisladas e identificadas, Aeromonas hydrophila, Vibrio fluvialis y Vibrio furnissii, han sido descritas como causantes de diarrea en humano y como patógeno muy agresivo en cultivos de Ciprinus carpio. Por esta razón se ha hecho mal uso y abuso de antibióticos para evitar y controlar la presencia de esta bacteria en los cultivos. El uso fu...

  15. The light organ symbiont Vibrio fischeri possesses a homolog of the Vibrio cholerae transmembrane transcriptional activator ToxR.

    OpenAIRE

    Reich, K A; Schoolnik, G K

    1994-01-01

    A cross-hybridizing DNA fragment to Vibrio cholerae toxR was cloned from the nonpathogenic light organ symbiont Vibrio fischeri, and three proteins homologous to V. cholerae ToxR, ToxS, and HtpG were deduced from its DNA sequence. V. fischeri ToxR was found to activate a V. cholerae ToxR-regulated promoter, and an antiserum raised against the amino-terminal domain of V. cholerae ToxR cross-reacts V. fischeri ToxR.

  16. Microflora of urogenital tract in pregnancy with asymptomatic bacterium

    International Nuclear Information System (INIS)

    The article contains results of research interrelationship from colonization of vagina and urinary tract diseases. E.coli one of the main factors in development asymptomatic bacterium. Presented high effects of penicillin medicaments and nitrofurans in treatment of asymptomatic bacterium

  17. Vibrio plantisponsor sp. nov., a diazotrophic bacterium isolated from a mangrove associated wild rice (Porteresia coarctata Tateoka)

    Digital Repository Service at National Institute of Oceanography (India)

    Rameshkumar, N.; Gomez-Gil, B.; Sproer, C.; Lang, E.; Kumar, N.D.; Krishnamurthi, S.; Nair, S.; Roque, A.

    strips; strain MSSRF60 T showed negative for arginine dihydrolase, Voges-Proskauer and positive for gelatinase were as strain MSSRF64 showed positive for arginine dihydrolase and Voges-Proskauer and negative for gelatinase. 2) Using method [29...-Proskauer. Positive for arginine dihydrolase, citrate utilization, indole production and aesculin hydrolysis. The strain produces amylases, - galactosidase and casienase. Ferments xylose, maltose, fructose, dextrose, galactose, melibiose, sucrose, L...

  18. Development and efficacy of an attenuated Vibrio harveyi vaccine candidate with cross protectivity against Vibrio alginolyticus.

    Science.gov (United States)

    Hu, Yong-hua; Deng, Tian; Sun, Bo-guang; Sun, Li

    2012-06-01

    Vibrio harveyi is a Gram-negative bacterial pathogen that can infect a wide range of marine animals. In previous studies, we have reported a virulent V. harveyi strain, T4D. In the present study, an attenuated mutant of T4D, T4DM, was obtained by selection of rifampicin resistance. Compared to the wild type, T4DM was different in whole-cell protein profile and much slower in growth rate when cultured in stress conditions caused by iron depletion. Virulence analysis showed that compared to T4D, T4DM exhibited a dramatically increased median lethal dose, impaired tissue dissemination capacity, defective hemolytic activity, and significantly reduced resistance against the killing effect of host serum. To examine the potential of T4DM as a live attenuated vaccine, Japanese flounder (Paralichthys olivaceus) were vaccinated with T4DM via intraperitoneal injection or immersion. The results showed that at one and two months post-vaccination, fish administered with T4DM via both approaches, in particular that of immersion, were effectively protected against not only V. harveyi but also Vibrio alginolyticus, another important fish pathogen. Microbiological analysis showed that following immersion vaccination, T4DM was recovered from the internal organs of the vaccinated fish in a time-dependent manner within the first 6 days post-vaccination. Serum antibodies against V. harveyi and V. alginolyticus were detected in T4DM-vaccinated fish, and, compared to serum from control fish, serum from T4DM-vaccinated fish was significantly enhanced in bactericidal activity. These results indicate that T4DM is an attenuated strain with residual infectivity and that T4DM can induce effective cross-species protection against both V. harveyi and V. alginolyticus when used as a live immersion vaccine. PMID:22484605

  19. Use of phages to control Vibrio splendidus infection in the juvenile sea cucumber Apostichopus japonicus.

    Science.gov (United States)

    Li, Zhen; Li, Xiaoyu; Zhang, Jiancheng; Wang, Xitao; Wang, Lili; Cao, Zhenhui; Xu, Yongping

    2016-07-01

    In the present study, we isolated 3 bacteriophages with the ability to control Vibrio splendidus, a bacterium known to cause disease in the juvenile sea cucumber. These bacteriophages were designated as vB_VspS_VS-ABTNL-1 (PVS-1), vB_VspS_VS-ABTNL-2 (PVS-2) and vB_VspS_VS-ABTNL-3 (PVS-3). The ability of the 3 phages to inhibit the growth of V. splendidus VS-ABTNL was tested in vitro using each of the 3 phages individually or in the form of a cocktail of all 3 phages in the proportion of 1:1:1. All treated cultures produced a significant (P  0.05). The levels of nitric oxide synthase and acid phosphatase of sea cucumbers fed phage-containing diets were significantly (P  0.05) were detected among the 4 phage-fed treatments. An additional study was conducted in which 60 healthy sea cucumbers (23 ± 2 g) were randomly assigned to a control, an untreated group and a test group to investigate the effects of injecting phages by coelomic injection on the survival rate and enzyme activities in the coelomic fluid of the sea cucumbers. The control was injected with 1 ml of sterilized seawater while the untreated group and the test group were injected with the same volume of V. splendidus-ABTNL culture (3 × 10(5) CFU/mL). Then, the test group was injected with 1 ml of the 3 phage cocktail (MOI = 10). After 48 h, the activities of lysozyme, acid phosphatase and superoxide dismutase were elevated in the untreated group while the levels of these enzymes in the test group were similar to the blank control. After 10-day observation, the survival rate of the sea cucumber was 100% for the blank control, 80% for the test group and 20% for the negative control. The overall results of this experiment indicate that phage therapy increased the survival of sea cucumber infected with V. splendidus VS-ABTNL. The above results demonstrate that using phages, especially a combination of different phages, may be a feasible way to control Vibrio infection in the sea cucumber

  20. New tetracycline resistance determinant on R plasmids from Vibrio anguillarum.

    OpenAIRE

    Aoki, T.; Satoh, T.; Kitao, T.

    1987-01-01

    Two classes of tetracycline resistance determinants on R plasmids were detected in Vibrio anguillarum strains isolated from ayu (sweat fish; Plecoglossus altivelis) farms in Japan. Tetracycline resistance genes categorized as class B were prevalent from 1973 to 1977; however, a new tetracycline resistance gene, which was not classified into tetracycline resistance determinant class A, B, C, or D, has been prevalent since 1981.

  1. Genome sequence of the human pathogen Vibrio cholerae Amazonia.

    NARCIS (Netherlands)

    Thompson, C.C.; Marin, M.A.; Dias, G.M.; Dutilh, B.E.; Edwards, R.A.; Iida, T.; Thompson, F.L.; Vicente, A.C.

    2011-01-01

    Vibrio cholerae O1 Amazonia is a pathogen that was isolated from cholera-like diarrhea cases in at least two countries, Brazil and Ghana. Based on multilocus sequence analysis, this lineage belongs to a distinct profile compared to strains from El Tor and classical biotypes. The genomic analysis rev

  2. Molecular analysis of the emergence of pandemic Vibrio parahaemolyticus

    DEFF Research Database (Denmark)

    Boyd, EF; Cohen, AL; Naughton, LM;

    2008-01-01

    Background Vibrio parahaemolyticus is abundant in the aquatic environment particularly in warmer waters and is the leading cause of seafood borne gastroenteritis worldwide. Prior to 1995, numerous V. parahaemolyticus serogroups were associated with disease, however, in that year an O3:K6 serogroup...

  3. Vibrio damsela associated with diseased fish in Denmark

    DEFF Research Database (Denmark)

    Pedersen, Karl; Dalsgaard, Inger; Larsen, J.L.

    1997-01-01

    A total of 26 Vibrio damsela strains were isolated in Denmark. Fifteen strains were isolated from the head kidney of rainbow trout (Oncorhynchus mykiss) in aquaculture, eight were from organs of two stingrays (Dasyatis pastinaca) held in captivity, two were from organs and pathological material of...

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

    Science.gov (United States)

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

    2006-01-01

    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

  5. Vibrios associated with mortality in cultured plaice Pleuronectes platessa fry

    DEFF Research Database (Denmark)

    Pedersen, Karl; Austin, B.; Austin, D.A.; Larsen, J.L.

    1999-01-01

    Fifty two bacterial strains, identified as Vibrio spp., were isolated from diseased plaice fry. The most numerous group comprised V. anguillarum (26/52), of which 3 isolates belonged to serogroup O2a, 16 corresponded to serogroup O18, and 7 isolates were nontypeable. All serogroup O18 isolates ha...

  6. Quorum Sensing Enhances the Stress Response in Vibrio cholerae▿

    OpenAIRE

    Joelsson, Adam; Kan, Biao; Jun ZHU

    2007-01-01

    Vibrio cholerae lives in aquatic environments and causes cholera. Here, we show that quorum sensing enhances V. cholerae viability under certain stress conditions by upregulating the expression of RpoS, and this regulation acts through HapR, suggesting that a quorum-sensing-enhanced stress response plays a role in V. cholerae environmental survival.

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

    OpenAIRE

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

    2013-01-01

    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.

  8. Phage specific for Vibrio cholerae O139 Bengal.

    OpenAIRE

    Albert, M J; Bhuiyan, N A; Rahman, A; Ghosh, A. N.; Hultenby, K; Weintraub, A; Nahar, S; Kibriya, A K; Ansaruzzaman, M; Shimada, T

    1996-01-01

    From the stool of a Vibrio cholerae O139 Bengal-infected patient, a phage that specifically lysed capsulated V. cholerae O139 strains only was isolated. The phage is useful for the confirmatory diagnosis of V. cholerae O139 infection and for the differentiation of variants that lack the capsule.

  9. Nontoxigenic Vibrio cholerae Septicemia in an Immunocompromised Patient

    OpenAIRE

    Kamran Kadkhoda; Heather Adam; Gilmour, Matthew W.; Hammond, Gregory W.

    2012-01-01

    We report a recent case of non-O1, non-O139, nontoxigenic Vibrio cholerae septicemia in a post-liver-transplant immunocompromised patient associated with prior seafood consumption. Non-O1, non-O139 V. cholerae strains have been reported in several cases of extraintestinal infections and seem to be emerging infectious agents especially in patients with immunocompromising conditions.

  10. Outbreak of Vibrio parahaemolyticus Sequence Type 120, Peru, 2009

    Science.gov (United States)

    Gonzalez-Escalona, Narjol; Gavilan, Ronnie G.; Toro, Magaly; Zamudio, Maria L.

    2016-01-01

    In 2009, an outbreak of Vibrio parahaemolyticus occurred in Piura, Cajamarca, Lambayeque, and Lima, Peru. Whole-genome sequencing of clinical and environmental samples from the outbreak revealed a new V. parahaemolyticus clone. All the isolates identified belonged to a single clonal complex described exclusively in Asia before its emergence in Peru. PMID:27315090

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

    Science.gov (United States)

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

    2012-11-15

    Combined vaccines are immunological products intended for immunization against multifactorial infectious diseases caused by different types or variants of pathogens. In this study, the effectiveness of Vibrio alginolyticus (Va), Vibrio harveyi (Vh), Vibrio vulnificus (Vv) and infectious spleen and kidney necrosis virus (ISKNV), an iridovirus, combined-vaccine (Vibrio and ISKNV combined vaccines, VICV), Va+Vh+Vv inactive vaccine (VIV) and ISKNV whole cell inactive vaccine (IWCIV) in Epinephelus coioides were evaluated using various immunological parameters including antibody titer, serum lysozyme activity (LA), respiratory burst (RB) activity, bactericidal activity (BA) and relative percentage survival (RPS). E. coioides immunized with VICV and challenged with Va+Vh+Vv+ISKNV had an RPS of 80%. The RPS was 73.3% in E. coioides immunized with VIV and challenged with Va+Vh+Vv. E. coioides immunized with IWCIV and challenged with ISKNV had an RPS of 69.6%. Serum LA in the vaccinated group was significantly higher than the control group on days 21 and 28 post-vaccination (P0.05). After immunization with VICV, BA values of blood leucocytes and head kidney cells increased significantly more than spleen cells. BA value of blood leucocytes was higher than that in head kidney cells. There were distinct difference between BA values in head kidney cells and in spleen cells (P<0.05) as well as between BA value of blood leucocytes and head kidney cells (P<0.01). E. coioides vaccinated with VICV have significantly higher antibody levels than control groupers (P<0.01). Our study suggests that the VICV candidate can effectively protect groupers against multiple bacterial and viral pathogens. PMID:23010220

  12. Household Transmission of Vibrio cholerae in Bangladesh.

    Directory of Open Access Journals (Sweden)

    Jonathan D Sugimoto

    2014-11-01

    Full Text Available 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.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.Direct exposure contributes substantially to endemic transmission of symptomatic cholera in an urban setting. We provide the first estimate of

  13. Proteolysis of virulence regulator ToxR is associated with entry of Vibrio cholerae into a dormant state.

    Directory of Open Access Journals (Sweden)

    Salvador Almagro-Moreno

    2015-04-01

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

  14. Design of Vibrio 16S rRNA Gene Specific Primers and Their Application in the Analysis of Seawater Vibrio Community

    Institute of Scientific and Technical Information of China (English)

    LIU Yong; YANG Guanpin; WANG Hualei; CHEN Jixiang; SHI Xianming; ZOU Guiwei; WEI Qiwei; SUN Xiuqin

    2006-01-01

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

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

    Science.gov (United States)

    González, Yael; Camarena, Laura; Dreyfus, Georges

    2015-03-01

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

  16. Isolation and molecular identification of Vibrio spp. by sequencing of 16S rDNA from seafood, meat and meat products in Libya

    OpenAIRE

    S. M. Azwai; Alfallani, E.A.; S.K. Abolghait; Garbaj, A.M.; Naas, H.T.; Moawad, A.A.; F.T. Gammoudi; Rayes, H.M.; Barbieri, I.; Eldaghayes, I.M.

    2016-01-01

    The genus Vibrio includes several food-borne pathogens that cause a spectrum of clinical conditions including septicemia, cholera and milder forms of gastroenteritis. Several Vibrio spp. are commonly associated with food-borne transmission including Vibrio cholerae, Vibrio parahemolyticus, and Vibrio vulnificus. Microbiological analysis for enumeration and isolation of Vibrio spp. were carried out for a total of 93 samples of seafood, meat and meat products from different geographic localitie...

  17. Mechanisms underlying the additive and redundant Qrr phenotypes in Vibrio harveyi and Vibrio cholerae.

    Science.gov (United States)

    Hunter, Geoffrey A M; Keener, James P

    2014-01-01

    Vibrio harveyi and Vibrio cholerae regulate their virulence factors according to the local cell-population density in a regulatory system called quorum sensing. Their quorum sensing systems contain a small RNA (sRNA) circuit to regulate expression of a master transcriptional regulator via multiple quorum regulated RNA (Qrr) and a protein chaperon Hfq. Experiments and genetic analysis show that their respective quorum sensing networks are topologically equivalent and have homologous components, yet they respond differently to the same experimental conditions. In particular, V. harveyi Qrr are additive because all of its Qrr are required to maintain wild-type-like repression of its master transcriptional regulator. Conversely, V. cholerae Qrr are redundant because any of its Qrr is sufficient to repress its master transcriptional regulator. Given the striking similarities between their quorum sensing systems, experimentalists have been unable to identify conclusively the mechanisms behind these phenotypic differences. Nevertheless, the current hypothesis in the literature is that dosage compensation is the mechanism underlying redundancy. In this work, we identify the mechanisms underlying Qrr redundancy using a detailed mathematical model of the V. harveyi and V. cholerae sRNA circuits. We show that there are exactly two different cases underlying Qrr redundancy and that dosage compensation is unnecessary and insufficient to explain Qrr redundancy. Although V. harveyi Qrr are additive when the perturbations in Qrr are large, we predict that V. harveyi and V. cholerae Qrr are redundant when the perturbations in Qrr are small. We argue that the additive and redundant Qrr phenotypes can emerge from parametric differences in the sRNA circuit. In particular, we find that the affinity of Qrr and its expression relative to the master transcriptional regulator determine the level of redundancy in V. harveyi and V. cholerae. Furthermore, the additive and redundant Qrr

  18. Molecular epidemiology of Vibrio cholerae associated with flood in Brahamputra River valley, Assam, India.

    Science.gov (United States)

    Bhuyan, Soubhagya K; Vairale, Mohan G; Arya, Neha; Yadav, Priti; Veer, Vijay; Singh, Lokendra; Yadava, Pramod K; Kumar, Pramod

    2016-06-01

    Cholera is often caused when drinking water is contaminated through environmental sources. In recent years, the drastic cholera epidemics in Odisha (2007) and Haiti (2010) were associated with natural disasters (flood and Earthquake). Almost every year the state of Assam India witnesses flood in Brahamputra River valley during reversal of wind system (monsoon). This is often followed by outbreak of diarrheal diseases including cholera. Beside the incidence of cholera outbreaks, there is lack of experimental evidence for prevalence of the bacterium in aquatic environment and its association with cholera during/after flood in the state. A molecular surveillance during 2012-14 was carried out to study prevalence, strain differentiation, and clonality of Vibrio cholerae in inland aquatic reservoirs flooded by Brahamputra River in Assam. Water samples were collected, filtered, enriched in alkaline peptone water followed by selective culturing on thiosulfate bile salt sucrose agar. Environmental isolates were identified as V. cholerae, based on biochemical assays followed by sero-grouping and detailed molecular characterization. The incidence of the presence of the bacterium in potable water sources was higher after flood. Except one O1 isolate, all of the strains were broadly grouped under non-O1/non-O139 whereas some of them did have cholera toxin (CT). Surprisingly, we have noticed Haitian ctxB in two non-O1/non-O139 strains. MLST analyses based on pyrH, recA and rpoA genes revealed clonality in the environmental strains. The isolates showed varying degree of antimicrobial resistance including tetracycline and ciprofloxacin. The strains harbored the genetic elements SXT constins and integrons responsible for multidrug resistance. Genetic characterization is useful as phenotypic characters alone have proven to be unsatisfactory for strain discrimination. An assurance to safe drinking water, sanitation and monitoring of the aquatic reservoirs is of utmost importance for

  19. Selective Media for In Vitro Activity Evaluation of Bacterial Biocontrol Against Pathogenic Vibrio

    OpenAIRE

    ALIM ISNANSETYO; MUHTADI; INDAH ISTIQOMAH; KAMISO HANDOYO NITIMULYO; TRIYANTO

    2011-01-01

    In vitro activity test is a critical evaluation to screen the potential biocontrol agent. We developed a selective medium for quantitative in vitro activity evaluation of bacterial biocontrol agents against pathogenic Vibrio in aquaculture. Sensitivity test of bacterial biocontrol and Vibrio spp. to nine antibiotics showed that oxytetracycline inhibited the growth of Vibrio spp., but did not inhibit the growth of the bacterial biocontrol. This selective inhibition activity of oxytetracycline ...

  20. Quantitative Microbial Risk Assessment of Pathogenic Vibrios in Marine Recreational Waters of Southern California

    OpenAIRE

    Dickinson, Gregory; Lim, Keah-ying; Jiang, Sunny C.

    2013-01-01

    This study investigated the occurrence of three types of vibrios in Southern California recreational beach waters during the peak marine bathing season in 2007. Over 160 water samples were concentrated and enriched for the detection of vibrios. Four sets of PCR primers, specific for Vibrio cholerae, V. parahaemolyticus, and V. vulnificus species and the V. parahaemolyticus toxin gene, respectively, were used for the amplification of bacterial genomic DNA. Of 66 samples from Doheny State Beach...

  1. Antimicrobial effect of dietary oregano essential oil against Vibrio bacteria in shrimps

    OpenAIRE

    Gracia-Valenzuela M.H.; Vergara-Jiménez M.J.; Baez-Flores M.E.; Cabrera-Chavez F.

    2014-01-01

    The effect of dietary oregano essential oils on the growth of Vibrio bacteria in shrimps was evaluated. Shrimps were fed: (i) food with oregano oil with a high level of thymol; (ii) food with oregano oil with a high level of carvacrol, and (iii) food without oregano oil (the control). The animals were infected by three species of Vibrio (vulnificus, parahaemolyticus and cholerae). The microbial counts of Vibrio species were significantly lower (p

  2. Differential complement activation and susceptibility to human serum bactericidal action by Vibrio species.

    OpenAIRE

    1983-01-01

    The ability of Vibrio vulnificus to resist human serum bactericidal action and to activate human complement was compared with similar cultures of Vibrio cholerae and Vibrio parahaemolyticus. Both V. vulnificus and V. parahaemolyticus had similar survival rates in sera and were much more resistant to killing than was V. cholerae. In contrast, V. vulnificus activated significantly less serum complement than did V. cholerae and V. parahaemolyticus. The relative ability of V. vulnificus to surviv...

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

    Science.gov (United States)

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

    2015-02-10

    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 (1.2×10(5)±8.0×10(3) 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

  4. Determining vaccination frequency in farmed rainbow trout using Vibrio anguillarum O1 specific serum antibody measurements.

    Directory of Open Access Journals (Sweden)

    Lars Holten-Andersen

    Full Text Available 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

  5. Molecular and Genomic Characterization of Vibrio mimicus Isolated from a Frozen Shrimp Processing Facility in Mexico

    Science.gov (United States)

    Guardiola-Avila, Iliana; Acedo-Felix, Evelia; Sifuentes-Romero, Itzel; Yepiz-Plascencia, Gloria; Gomez-Gil, Bruno; Noriega-Orozco, Lorena

    2016-01-01

    Vibrio mimicus is a gram-negative bacterium responsible for diseases in humans. Three strains of V. mimicus identified as V. mimicus 87, V. mimicus 92 and V. mimicus 93 were isolated from a shrimp processing facility in Guaymas, Sonora, Mexico. The strains were analyzed using several molecular techniques and according to the cluster analysis they were different, their similarities ranged between 51.3% and 71.6%. ERIC-PCR and RAPD (vmh390R) were the most discriminatory molecular techniques for the differentiation of these strains. The complete genomes of two strains (V. mimicus 87, renamed as CAIM 1882, and V. mimicus 92, renamed as CAIM 1883) were sequenced. The sizes of the genomes were 3.9 Mb in both strains, with 2.8 Mb in ChI and 1.1 Mb in ChII. A 12.7% difference was found in the proteome content (BLAST matrix). Several virulence genes were detected (e.g. capsular polysaccharide, an accessory colonization factor and genes involved in quorum-sensing) which were classified in 16 categories. Variations in the gene content between these genomes were observed, mainly in proteins and virulence genes (e.g., hemagglutinin, mobile elements and membrane proteins). According to these results, both strains were different, even when they came from the same source, giving an insight of the diversity of V. mimicus. The identification of various virulence genes, including a not previously reported V. mimicus gene (acfD) in ChI in all sequenced strains, supports the pathogenic potential of this species. Further analysis will help to fully understand their potential virulence, environmental impact and evolution. PMID:26730584

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

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    Andrew J. Collins

    2012-05-01

    Full Text Available 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 (MAMPs were identified. Among these was a complete open reading frame (ORF to a putative peptidoglycan recognition protein (EsPGRP5 that has 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 NFκB signaling pathway, putative members of the complement pathway, the carbohydrate binding protein galectin, and cephalotoxin. Quantitative PCR of complement-related genes, cephalotoxin, EsPGRP5, and a nitric oxide synthase showed differential expression in circulating hemocytes isolated from adult squid with colonized light organs compared to those for which the symbionts were removed. These data suggest that the presence of the symbiont influences gene expression of the cellular innate immune system of the host.

  7. Application of bacterial lipopolysaccharide to improve survival of the black tiger shrimp after Vibrio harveyi exposure.

    Science.gov (United States)

    Rungrassamee, Wanilada; Maibunkaew, Sawarot; Karoonuthaisiri, Nitsara; Jiravanichpaisal, Pikul

    2013-10-01

    This study investigates an effect of bacterial lipopolysaccharide (LPS) as feed supplement to improve immunity of the black tiger shrimp (Penaeus monodon). LPS was coated to commercial feed pellets and given to the shrimp once or twice a day for 10 days before an exposure with shrimp pathogenic bacterium Vibrio harveyi. The growth rates, percent weight gains, total hemocyte and granulocyte counts and survival rates of shrimp between the LPS-coated pellet fed groups and a control group where shrimp fed with commercial feed pellets were compared. After 10 days of the feeding trials, growth rates were not significantly different in all groups, suggesting no toxicity from LPS supplement. To determine beneficial effect of LPS diets, each group was subsequently exposed to V. harveyi by immersion method and the survival rates were recorded for seven days after the immersion. Regardless of the dosages of LPS, the shrimp groups fed with LPS-coated pellets showed higher survival rates than the control group. There was no significant difference in survival rates between the two LPS dosages groups. In addition to survival under pathogen challenge, we also determine effect of LPS on immune-related genes after 10-day feeding trial. Gene expression analysis in the P. monodon intestines revealed that antilipopolysaccharide factor isoform 3 (ALF3), C-type lectin, and mucine-like peritrophin (mucin-like PM) were expressed significantly higher in a group fed with LPS supplemental diet once or twice a day than in a control group. The transcript levels of C-type lectin and mucin-like PM had increased significantly when LPS was given once a day, while significant induction of ALF3 transcripts was observed when shrimp were fed with LPS twice a day. The up-regulation of the immune gene levels in intestines and higher resistance to V. harveyi of the shrimp fed with LPS provide the evidence for potential application of LPS as an immunostimulant in P. monodon farming. PMID:23751331

  8. Proteomic analysis of differentially expressed proteins in Penaeus monodon hemocytes after Vibrio harveyi infection

    Science.gov (United States)

    2010-01-01

    Background Viral and bacterial diseases can cause mass mortalities in commercial shrimp aquaculture. In contrast to studies on the antiviral response, the responses of shrimps to bacterial infections by high throughput techniques have been reported only at the transcriptional level and not at the translational level. In this study, a proteomic analysis of shrimp hemocytes to identify differentially expressed proteins in response to a luminous bacterium Vibrio harveyi was evaluated for its feasibility and is reported for the first time. Results The two-dimensional gel electrophoresis (2-DE) patterns of the hemocyte proteins from the unchallenged and V. harveyi challenged shrimp, Penaeus monodon, at 24 and 48 h post infection were compared. From this, 27 differentially expressed protein spots, and a further 12 weakly to non-differentially regulated control spots, were selected for further analyses by the LC-ESI-MS/MS. The 21 differentially expressed proteins that could be identified by homologous annotation were comprised of proteins that are directly involved in the host defense responses, such as hemocyanin, prophenoloxidase, serine proteinase-like protein, heat shock protein 90 and alpha-2-macroglobulin, and those involved in signal transduction, such as the14-3-3 protein epsilon and calmodulin. Western blot analysis confirmed the up-regulation of hemocyanin expression upon bacterial infection. The expression of the selected proteins which were the representatives of the down-regulated proteins (the 14-3-3 protein epsilon and alpha-2-macroglobulin) and of the up-regulated proteins (hemocyanin) was further assessed at the transcription level using real-time RT-PCR. Conclusions This work suggests the usefulness of a proteomic approach to the study of shrimp immunity and revealed hemocyte proteins whose expression were up regulated upon V. harveyi infection such as hemocyanin, arginine kinase and down regulated such as alpha-2-macroglobulin, calmodulin and 14

  9. Proteomic analysis of differentially expressed proteins in Penaeus monodon hemocytes after Vibrio harveyi infection

    Directory of Open Access Journals (Sweden)

    Fang Lo Chu

    2010-07-01

    Full Text Available Abstract Background Viral and bacterial diseases can cause mass mortalities in commercial shrimp aquaculture. In contrast to studies on the antiviral response, the responses of shrimps to bacterial infections by high throughput techniques have been reported only at the transcriptional level and not at the translational level. In this study, a proteomic analysis of shrimp hemocytes to identify differentially expressed proteins in response to a luminous bacterium Vibrio harveyi was evaluated for its feasibility and is reported for the first time. Results The two-dimensional gel electrophoresis (2-DE patterns of the hemocyte proteins from the unchallenged and V. harveyi challenged shrimp, Penaeus monodon, at 24 and 48 h post infection were compared. From this, 27 differentially expressed protein spots, and a further 12 weakly to non-differentially regulated control spots, were selected for further analyses by the LC-ESI-MS/MS. The 21 differentially expressed proteins that could be identified by homologous annotation were comprised of proteins that are directly involved in the host defense responses, such as hemocyanin, prophenoloxidase, serine proteinase-like protein, heat shock protein 90 and alpha-2-macroglobulin, and those involved in signal transduction, such as the14-3-3 protein epsilon and calmodulin. Western blot analysis confirmed the up-regulation of hemocyanin expression upon bacterial infection. The expression of the selected proteins which were the representatives of the down-regulated proteins (the 14-3-3 protein epsilon and alpha-2-macroglobulin and of the up-regulated proteins (hemocyanin was further assessed at the transcription level using real-time RT-PCR. Conclusions This work suggests the usefulness of a proteomic approach to the study of shrimp immunity and revealed hemocyte proteins whose expression were up regulated upon V. harveyi infection such as hemocyanin, arginine kinase and down regulated such as alpha-2-macroglobulin

  10. Prevalences of pathogenic and nonpathogenic Vibrio parahaemolyticus in mollusks from the Spanish Mediterranean Coast

    Directory of Open Access Journals (Sweden)

    Carmen eLopez-Joven

    2015-07-01

    Full Text Available Vibrio parahaemolyticus is a well-recognized pathogen of humans. To better understand the ecology of the human-pathogenic variants of this bacterium in the environment, a study on the prevalence in bivalves of pathogenic variants (tlh + and tdh+ and/or trh+ versus a nonpathogenic one (only tlh+ as species marker for V. parahaemolyticus, was performed in two bays in Catalonia, Spain. Environmental factors that might affect dynamics of both variants of V. parahaemolyticus were taken into account. The results showed that the global prevalence of total V. parahaemolyticus found in both bays was 14.2% (207/1459. It was, however, significantly dependent on sampling point, campaign (year and bivalve species. Pathogenic variants of V. parahaemolyticus (tdh+ and/or trh+ were detected in 3.8% of the samples (56/1459, meaning that the proportion of bivalves who contained tlh gene were contaminated by pathogenic V. parahaemolyticus strains is 27.1% (56/207. Moreover, the presence of pathogenic V. parahaemolyticus (trh+ was significantly correlated with water salinity, thus the probability of finding pathogenic V. parahaemolyticus decreased 1.45 times with every salinity unit (ppt increased. Additionally, data showed that V. parahaemolyticus could establish close associations with Ruditapes spp. (P-value < 0.001, which could enhance the transmission of illness to human by pathogenic variants, when clams were eaten raw or slightly cooked.This study provides information on the abundance, ecology and characteristics of total and human-pathogenic V. parahaemolyticus variants associated with bivalves cultured in the Spanish Mediterranean Coast.

  11. A metalloprotease secreted by the type II secretion system links Vibrio cholerae with collagen.

    Science.gov (United States)

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

    2015-03-01

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

  12. Enterobacteria and Vibrio from Macrobrachium amazonicum prawn farming in Fortaleza, Ceará, Brazil

    Institute of Scientific and Technical Information of China (English)

    Manoel de Arajo Neto Paiva; Rossana de Aguiar Cordeiro; Andr Jalles Monteiro; Jos Jlio Costa Sidrim; Marcos Fbio Gadelha Rocha; Jamille Alencar Sales; Glaucia Morgana de Melo Guedes; Yago Brito de Ponte; Clia Maria de Souza Sampaio; Jos Luciano Bezerra Moreira; Lucas Pereira de Alencar

    2016-01-01

    Objective: To investigate the isolation of enterobacteria associated with Macrobrachium amazonicum (M. amazonicum) farming and evaluate the in vitro antimicrobial susceptibility of Vibrio strains. Methods: Strains were isolated from female M. amazonicum prawns and environmental and hatchery water. Biochemical assays were used to identify bacterial genera and those belonging to the genus Vibrio were submitted to further analyses for species identification, through Vitek 2 automated system and serotyping. Susceptibility test was performed according to Clinical Laboratory Standards Institute. Results: The following genera of enterobacteria were recovered: Enterobacter (n=11), Citrobacter (n=10), Proteus (n=2), Serratia (n=2), Kluyvera (n=2), Providencia (n=2), Cedecea (n=1), Escherichia (n=1), Edwardsiella (n=1) and Buttiauxella (n=1). As for Vibrio, three species were identified: Vibrio cholerae non-O1/non-O139 (n=4), Vibrio vulnificus (V. vulnificus) (n=1) and Vibrio mimicus (n=1). Vibrio spp. showed minimum inhibitory concentrations values within the susceptibility range established by Clinical Laboratory Standards Institute for almost all antibiotics, except for V. vulnificus, which presented intermediate profile to ampicillin. Conclusions:Enterobacteria do not seem to be the most important pathogens associated with M. amazonicum farming, whereas the recovery of Vibrio spp. from larviculture, with emphasis on Vibrio cholerae and V. vulnificus, deserves special attention due to their role as potentially zoonotic aquaculture-associated pathogens. Furthermore, the intermediate susceptibility of V. vulnificus to ampicillin reflects the importance of monitoring drug use in prawn farming.

  13. Diversity and pathogenic potential of vibrios isolated from Abrolhos Bank corals.

    Science.gov (United States)

    Alves, Nelson; Neto, Oswaldo S Maia; Silva, Bruno S O; De Moura, Rodrigo L; Francini-Filho, Ronaldo B; Barreira E Castro, Clovis; Paranhos, Rodolfo; Bitner-Mathé, Blanche C; Kruger, Ricardo H; Vicente, Ana Carolina P; Thompson, Cristiane C; Thompson, Fabiano L

    2010-02-01

    We performed the first taxonomic characterization of vibrios and other culturable microbiota from apparently healthy and diseased Brazilian-endemic corals at the Abrolhos reef bank. The diseases affecting corals were tissue necrosis in Phyllogorgia dillatata, white plague and bleaching in Mussismilia braziliensis and bleaching in Mussismilia hispida. Bacterial isolates were obtained from mucus of 22 coral specimens originated from the Abrolhos Bank (i.e. Itacolomis reef, Recife de Fora reef and Santa Barbara Island) in 2007. Vibrios counts in the water and coral mucus were approximately 104 cfu ml(-1) and 106 cfu ml(-1) respectively. One hundred and thirty-one representative vibrio isolates were identified. Most vibrio isolates (n = 79) fell into the core group using the pyrH identification marker. According to our analysis, diseased corals did not possess a unique vibrio microbiota. Vibrio species encompassed strains originated from both apparently healthy and diseased corals. The pathogenic potential of representative vibrio isolates (V. alginolyticus 40B, V. harveyi-like 1DA3 and V. coralliilyticus 2DA3) were evaluated in a standardized bioassay using the animal model Drosophila melanogaster and caused 25-88% mortality. This is the first taxonomic characterization of the culturable microbiota from the Brazilian-endemic corals. Endemic Brazilian corals are a reservoir of the vibrio core group. Vibrio alginolyticus, V. harveyi and V. coralliilyticus are dominant in the mucus of these corals and may be a normal component of the holobiont. PMID:23766002

  14. The Zymovars of Vibrio cholerae: Multilocus Enzyme Electrophoresis of Vibrio cholerae

    Directory of Open Access Journals (Sweden)

    Fernanda S Freitas

    2002-06-01

    Full Text Available Zymovars analysis also known as multilocus enzyme electrophoresis is applied here to investigate the genetic variation of Vibrio cholerae strains and characterise strains or group of strains of medical and epidemiological interest. Fourteen loci were analyzed in 171 strains of non-O1 non-O139, 32 classical and 61 El Tor from America, Africa, Europe and Asia. The mean genetic diversity was 0.339. It is shown that the same O antigen (both O1 and non-O1 may be present in several geneticaly diverse (different zymovars strains. Conversely the same zymovar may contain more than one serogroup. It is confirmed that the South American epidemic strain differs from the 7th pandemic El Tor strain in locus LAP (leucyl leucyl aminopeptidase. Here it is shown that this rare allele is present in 1 V. mimicus and 4 non-O1 V. cholerae. Non toxigenic O1 strains from South India epidemic share zymovar 14A with the epidemic El Tor from the 7th pandemic, while another group have diverse zymovars. The sucrose negative epidemic strains isolated in French Guiana and Brazil have the same zymovar of the current American epidemic V. cholerae.

  15. Management of multipartite genomes: the Vibrio cholerae model.

    Science.gov (United States)

    Val, Marie-Eve; Soler-Bistué, Alfonso; Bland, Michael J; Mazel, Didier

    2014-12-01

    A minority of bacterial species has been found to carry a genome divided among several chromosomes. Among these, all Vibrio species harbor a genome split into two chromosomes of uneven size, with distinctive replication origins whose replication firing involves common and specific factors. Most of our current knowledge on replication and segregation in multi-chromosome bacteria has come from the study of Vibrio cholerae, which is now the model organism for this field. It has been firmly established that replication of the two V. cholerae chromosomes is temporally regulated and coupled to the cell cycle, but the mediators of these processes are as yet mostly unknown. The two chromosomes are also organized along different patterns within the cell and occupy different subcellular domains. The selective advantages provided by this partitioning into two replicons are still unclear and are a key motivation for these studies. PMID:25460805

  16. Establishment and application of a loop-mediated isothermal amplification method for rapid diagnosis of Vibrio cholerae%霍乱弧菌LAMP快速检测方法的建立及应用

    Institute of Scientific and Technical Information of China (English)

    柯雪梅; 陈胤瑜; 高璐璐; 杜正平; 冯雪梅; 廖如燕; 陈志永; 曹以诚; 陈清

    2009-01-01

    目的 建立环介导等温扩增技术(LAMP)快速检测霍乱弧菌.方法 针对霍乱弧菌外膜蛋白的ompW基因设计特异引物,优化反应条件,建立霍乱弧菌的LAMP检测方法.通过对47株细菌及模拟污染现场,检测该方法的灵敏度、特异度和实用性.结果 活菌计数方法表明建立的LAMP方法检测霍乱弧菌的灵敏度为1.6×10~2 cfu/ml.在人工污染霍乱弧菌的粪便及海水标本中检测的敏感度为1.6×10~3 cfu/ml,在牛奶标本中敏感度为1.6×10~4 cfu/ml.检测21株霍乱弧菌均为阳性,26株非霍乱菌则全部阴性,特异度为100%.结论 建立的LAMP方法检测霍乱弧菌灵敏度、特异度高,可用于霍乱现场监测和流行病学调查.%Objective To establish a loop-mediated isothermal amplification (LAMP) method for rapid diagnosis of Vibrio cholerae. Method Based on the ompW nucleic sequence of Vibrio cholerae, a pair of primers was designed for LAMP. The reaction conditions were optimized, and the specificity, sensitivity, and practicability of LAMP were tested using 47 baterial strains and simulated contaminated sites. Results The results of viable bacterium count showed that LAMP was capable of detecting Vibrio cholerae at a level as low as 1.6×10~2 cfu/ml. The minimal detectable concentration was 1.6×10~3 cfu/ml for simulated contaminated samples such as feces and seawater, and 1.6×10~4 cfu/ml for contaminated milk. All the 21 strains of Vibrio cholerae yielded positive results in LAMP, and the 26 strains of other bacteria all showed negative results, with a detection specificity of 100%. Conclusion The established LAMP method has high specificity and sensitivity for detecting Vibrio cholerae and is applicable in field monitoring and epidemiological study of Vibrio cholerae.

  17. Toxic factors of Vibrio strains pathogenic to shrimp

    OpenAIRE

    Goarant, Cyrille; Herlin, Jose; Brizard, Raphael; Marteau, Anne-laure; Martin, C.; Martin, B.(CERN, Geneva, Switzerland)

    2000-01-01

    Vibriosis is a major disease problem in shrimp aquaculture. 'Syndrome 93' is a seasonal juvenile vibriosis caused by Vibrio penaeicida which affects Litopenaeus stylirostris in grow-out ponds in New Caledonia. This study assessed the toxic activities of extracellular products (ECPs) from V: penaeicida, V. alginolyticus and V, nigripulchritudo using in vivo injections in healthy juvenile L. stylirostris (= Penaeus stylirostris) and in vitro assays on shrimp primary cell cultures and the fish c...

  18. Ethanolamine utilization in Vibrio alginolyticus

    OpenAIRE

    Khatri Neelam; Khatri Indu; Subramanian Srikrishna; Raychaudhuri Saumya

    2012-01-01

    Abstract Ethanolamine is used as an energy source by phylogenetically diverse bacteria including pathogens, by the concerted action of proteins from the eut-operon. Previous studies have revealed the presence of eutBC genes encoding ethanolamine-ammonia lyase, a key enzyme that breaks ethanolamine into acetaldehyde and ammonia, in about 100 bacterial genomes including members of gamma-proteobacteria. However, ethanolamine utilization has not been reported for any member of the Vibrio genus. O...

  19. Photodynamic Antimicrobial Chemotherapy in Aquaculture: Photoinactivation Studies of Vibrio fischeri

    OpenAIRE

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

    2011-01-01

    Background Photodynamic 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 aquaculture water, to reproduce phot...

  20. Inhibition of virulence potential of Vibrio cholerae by natural compounds

    OpenAIRE

    Yamasaki, Shinji; Asakura, Masahiro; Neogi, Sucharit Basu; Hinenoya, Atsushi; Iwaoka, Emiko; Aoki, Shunji

    2011-01-01

    The rise in multi-drug resistant Vibrio cholerae strains is a big problem in treatment of patients suffering from severe cholera. Only a few studies have evaluated the potential of natural compounds against V. cholerae. Extracts from plants like ‘neem’, ‘guazuma’, ‘daio’, apple, hop, green tea and elephant garlic have been shown to inhibit bacterial growth or the secreted cholera toxin (CT). However, inhibiting bacterial growth like common antimicrobial agents may also impose selective pressu...

  1. Synergistic activation of quorum sensing in Vibrio harveyi.

    Science.gov (United States)

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

    2015-09-15

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

  2. Ion-swimming speed variation of Vibrio cholerae cells

    Indian Academy of Sciences (India)

    Anindito Sen; Ranjan K Nandi; Amar N Ghosh

    2005-09-01

    In the present work we report the variation in swimming speed of Vibrio cholerae with respect to the change in concentration of sodium ions in the medium. We have also studied the variation in swimming speed with respect to temperature. We find that the swimming speed initially shows a linear increase with the increase of the sodium ions in the medium and then plateaus. The range within which the swimming speed attains saturation is approximately the same at different temperatures.

  3. α-Hydroxyketone Synthesis and Sensing by Legionella and Vibrio

    OpenAIRE

    Hubert Hilbi; André Tiaden

    2012-01-01

    Bacteria synthesize and sense low molecular weight signaling molecules, termed autoinducers, to measure their population density and community complexity. One class of autoinducers, the α-hydroxyketones (AHKs), is produced and detected by the water-borne opportunistic pathogens Legionella pneumophila and Vibrio cholerae, which cause Legionnaires’ disease and cholera, respectively. The “Legionella quorum sensing” (lqs) or “cholera quorum sensing” (cqs) genes encode enzymes that produce and sen...

  4. Biocompatible capped iron oxide nanoparticles for Vibrio cholerae detection

    Science.gov (United States)

    Sharma, Anshu; Baral, Dinesh; Rawat, Kamla; Solanki, Pratima R.; Bohidar, H. B.

    2015-05-01

    We report the studies relating to fabrication of an efficient immunosensor for Vibrio cholerae detection. Magnetite (iron oxide (Fe3O4)) nanoparticles (NPs) have been synthesized by the co-precipitation method and capped by citric acid (CA). These NPs were electrophoretically deposited onto indium-tin-oxide (ITO)-coated glass substrate and used for immobilization of monoclonal antibodies against Vibrio cholerae (Ab) and bovine serum albumin (BSA) for Vibrio cholerae detection using an electrochemical technique. The structural and morphological studies of Fe3O4 and CA-Fe3O4/ITO were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and dynamic light scattering (DLS) techniques. The average crystalline size of Fe3O4, CA-Fe3O4 nanoparticles obtained were about 29 ± 1 nm and 37 ± 1 nm, respectively. The hydrodynamic radius of the nanoparticles was found to be 77.35 nm (Fe3O4) and 189.51 nm (CA-Fe3O4) by DLS measurement. The results of electrochemical response studies of the fabricated BSA/Ab/CA-Fe2O3/ITO immunosensor exhibits a good detection range of 12.5-500 ng mL-1 with a low detection limit of 0.32 ng mL-1, sensitivity 0.03 Ω/ng ml-1 cm-2, and reproducibility more than 11 times.

  5. Overexpression and export of Vibrio anguillarum metalloprotease in Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    Zhang Fengli; Chi Zhenming; Chen Jixiang; Wu Longfei; Liang Likun

    2007-01-01

    Vibrio anguillarum metalloprotease, an extracellular zinc metalloprotease involved in the virulence mechanism of Vibrio anguillarum, is synthesized from the empA gene as a 611-residue precursor and naturally secreted via Sec secretion pathway in Vibrio anguillarum. In this study, heterologous expression of the empA gene encoding metallopmtease and export of the recombinant metalloprotease in Escherichia coliwere examined. The empA gene was subcloned into pBAD24 with arabinose promoter and sequenced. The sequence encoded a polypeptide(611 amino acids)consisting of four domains: a signal peptide, an Nterminal propeptide, a mature region and a C-terminal propeptide. The empA gene inserted in plasmid pBAD24 was overexpressed in TOP10 strain of E. Coli after arabinose induction. The 36kDa polypeptide of the recombinant metalloprotease as the mature protease was further confirmed by SDS-PAGE and immunoblotting. It was found that recombinant metalloprotease with the EmpA activity and antigenicity wasexported into the periplasm of Escherichia coli cells via Sec translocation pathway, whereas it was secreted into extracellular environments in V. Anguillarum. The results imply that the expression, export and processing mechanism of the protein in E. Coli are similar to those in V. Anguillarum.

  6. Molecular epidemiology of non-O1 Vibrio cholerae and Vibrio mimicus in the U.S. Gulf Coast region.

    OpenAIRE

    Kaper, J B; Nataro, J P; Roberts, N C; Siebeling, R J; Bradford, H B

    1986-01-01

    Ten toxigenic Vibrio cholerae non-O1 and V. mimicus strains isolated from clinical and environmental sources in the U.S. Gulf Coast region were examined for genetic relatedness. Restriction digest patterns of chromosomal DNA and Southern blot analysis with a cholera toxin gene probe revealed that the strains exhibited greater genetic divergence than the highly conserved V. cholerae O1 strains isolated from clinical and sewage samples in this region.

  7. Isolation of a Bacterium Strain Degraded Agar

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    One in 58 strains of bacteria isolated from the compost showed clear colonies after a few days of growth on the plates containing medium made of only agar and water.Water suspension contained only agar (2 and 8g·L -1 ) with two controls (normal saline,LB medium) was inoculated with the bacterium BR5-1 to see whether there was an increasement of the alive bacteria concentration after 48 h of the growth.The results showed that there was a significant rising of the alive bacteria concentration in the agar susp...

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

    Science.gov (United States)

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

    2010-01-01

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

  9. Genome Sequence and Comparative Genomics Analysis of a Vibrio cholerae O1 Strain Isolated from a Cholera Patient in Malaysia

    Science.gov (United States)

    Osama, Abdulrazak; Gan, Han Ming; Teh, Cindy Shuan Ju; Yap, Kien-Pong

    2012-01-01

    The genome sequence analysis of a clinical Vibrio cholerae VC35 strain from an outbreak case in Malaysia indicates multiple genes involved in host adaptation and a novel Na+-driven multidrug efflux pump-coding gene in the genome of Vibrio cholerae with the highest similarity to VMA_001754 of Vibrio mimicus VMA223. PMID:23209200

  10. Genome Sequence and Comparative Genomics Analysis of a Vibrio cholerae O1 Strain Isolated from a Cholera Patient in Malaysia

    OpenAIRE

    Osama, Abdulrazak; Gan, Han Ming; Teh, Cindy Shuan Ju; Yap, Kien-Pong; Thong, Kwai-Lin

    2012-01-01

    The genome sequence analysis of a clinical Vibrio cholerae VC35 strain from an outbreak case in Malaysia indicates multiple genes involved in host adaptation and a novel Na+-driven multidrug efflux pump-coding gene in the genome of Vibrio cholerae with the highest similarity to VMA_001754 of Vibrio mimicus VMA223.

  11. Virulence Profiles of Vibrio vulnificus in German Coastal Waters, a Comparison of North Sea and Baltic Sea Isolates.

    Science.gov (United States)

    Bier, Nadja; Jäckel, Claudia; Dieckmann, Ralf; Brennholt, Nicole; Böer, Simone I; Strauch, Eckhard

    2015-12-01

    Vibrio vulnificus is a halophilic bacterium of coastal environments known for sporadically causing severe foodborne or wound infections. Global warming is expected to lead to a rising occurrence of V. vulnificus and an increasing incidence of human infections in Northern Europe. So far, infections in Germany were exclusively documented for the Baltic Sea coast, while no cases from the North Sea region have been reported. Regional variations in the prevalence of infections may be influenced by differences in the pathogenicity of V. vulnificus populations in both areas. This study aimed to compare the distribution of virulence-associated traits and genotypes among 101 V. vulnificus isolates from the Baltic Sea and North Sea in order to assess their pathogenicity potential. Furthermore, genetic relationships were examined by multilocus sequence typing (MLST). A high diversity of MLST sequences (74 sequence types) and differences regarding the presence of six potential pathogenicity markers were observed in the V. vulnificus populations of both areas. Strains with genotypes and markers associated with pathogenicity are not restricted to a particular geographic region. This indicates that lack of reported cases in the North Sea region is not caused by the absence of potentially pathogenic strains. PMID:26694432

  12. Virulence Profiles of Vibrio vulnificus in German Coastal Waters, a Comparison of North Sea and Baltic Sea Isolates

    Directory of Open Access Journals (Sweden)

    Nadja Bier

    2015-12-01

    Full Text Available Vibrio vulnificus is a halophilic bacterium of coastal environments known for sporadically causing severe foodborne or wound infections. Global warming is expected to lead to a rising occurrence of V. vulnificus and an increasing incidence of human infections in Northern Europe. So far, infections in Germany were exclusively documented for the Baltic Sea coast, while no cases from the North Sea region have been reported. Regional variations in the prevalence of infections may be influenced by differences in the pathogenicity of V. vulnificus populations in both areas. This study aimed to compare the distribution of virulence-associated traits and genotypes among 101 V. vulnificus isolates from the Baltic Sea and North Sea in order to assess their pathogenicity potential. Furthermore, genetic relationships were examined by multilocus sequence typing (MLST. A high diversity of MLST sequences (74 sequence types and differences regarding the presence of six potential pathogenicity markers were observed in the V. vulnificus populations of both areas. Strains with genotypes and markers associated with pathogenicity are not restricted to a particular geographic region. This indicates that lack of reported cases in the North Sea region is not caused by the absence of potentially pathogenic strains.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-01-01

    Vibrio cholerae, the bacterium that causes the disease cholera, controls virulence factor production and biofilm development in response to two extracellular quorum-sensing molecules, called autoinducers. The strongest autoinducer, called CAI-1 (for cholera autoinducer-1), was previously identified as (S)-3-hydroxytridecan-4-one. Biosynthesis of CAI-1 requires the enzyme CqsA. Here, we determine the CqsA reaction mechanism, identify the CqsA substrates as (S)-2-aminobutyrate and decanoyl coenzyme A, and demonstrate that the product of the reaction is 3-aminotridecan-4-one, dubbed amino-CAI-1. CqsA produces amino-CAI-1 by a pyridoxal phosphate-dependent acyl-CoA transferase reaction. Amino-CAI-1 is converted to CAI-1 in a subsequent step via a CqsA-independent mechanism. Consistent with this, we find cells release {ge}100 times more CAI-1 than amino-CAI-1. Nonetheless, V. cholerae responds to amino-CAI-1 as well as CAI-1, whereas other CAI-1 variants do not elicit a quorum-sensing response. Thus, both CAI-1 and amino-CAI-1 have potential as lead molecules in the development of an anticholera treatment.

  14. Development of a real-time resistance measurement for Vibrio parahaemolyticus detection by the lecithin-dependent hemolysin gene.

    Directory of Open Access Journals (Sweden)

    Guiming Xiang

    Full Text Available The marine bacterium Vibrio parahaemolyticus (V. parahaemolyticus causes gastroenteritis in humans via the ingestion of raw or undercooked contaminated seafood, and early diagnosis and prompt treatment are important for the prevention of V. parahaemolyticus-related diseases. In this study, a real-time resistance measurement based on loop-mediated isothermal amplification (LAMP, electrochemical ion bonding (Crystal violet and Mg(2+, real-time monitoring, and derivative analysis was developed. V. parahaemolyticus DNA was first amplified by LAMP, and the products (DNA and pyrophosphate represented two types of negative ions that could combine with a positive dye (Crystal violet and positive ions (Mg(2+ to increase the resistance of the reaction liquid. This resistance was measured in real-time using a specially designed resistance electrode, thus permitting the quantitative detection of V. parahaemolyticus. The results were obtained in 1-2 hours, with a minimum bacterial density of 10 CFU.mL(-1 and high levels of accuracy (97%, sensitivity (96.08%, and specificity (97.96% when compared to cultivation methods. Therefore, this simple and rapid method has a potential application in the detection of V. parahaemolyticus on a gene chip or in point-of-care testing.

  15. The thermostable direct hemolysin-related hemolysin (trh) gene of Vibrio parahaemolyticus: Sequence variation and implications for detection and function.

    Science.gov (United States)

    Nilsson, William B; Turner, Jeffrey W

    2016-07-01

    Vibrio parahaemolyticus is a leading cause of bacterial food-related illness associated with the consumption of undercooked seafood. Only a small subset of strains is pathogenic. Most clinical strains encode for the thermostable direct hemolysin (TDH) and/or the TDH-related hemolysin (TRH). In this work, we amplify and sequence the trh gene from over 80 trh+strains of this bacterium and identify thirteen genetically distinct alleles, most of which have not been deposited in GenBank previously. Sequence data was used to design new primers for more reliable detection of trh by endpoint PCR. We also designed a new quantitative PCR assay to target a more conserved gene that is genetically-linked to trh. This gene, ureR, encodes the transcriptional regulator for the urease gene cluster immediately upstream of trh. We propose that this ureR assay can be a useful screening tool as a surrogate for direct detection of trh that circumvents challenges associated with trh sequence variation. PMID:27094247

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

    Science.gov (United States)

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

    2016-03-01

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

  17. Proteomic analysis of differentially expressed proteins in the lymphoid organ of Vibrio harveyi-infected Penaeus monodon.

    Science.gov (United States)

    Chaikeeratisak, Vorrapon; Somboonwiwat, Kunlaya; Wang, Hao-Ching; Lo, Chu Fang; Tassanakajon, Anchalee

    2012-05-01

    The protein expression profiles of the lymphoid organ, taken from mock and systemic Vibrio harveyi-infected Penaeus monodon at 6 and 48 h post infection, were revealed. The considerable changes in the expression level of several proteins were observed between the mock and V. harveyi-infected shrimps. From 30 analyzed protein spots with 27 differentially expressed, 21 were known proteins with the most common of these being cytoskeleton proteins (33%) which were all down-regulated upon systemic bacterial infection. Other six proteins including four proteins that are involved in the shrimp immunity (alpha-2-macroglobulin, transglutaminase, heat shock protein 1 and hemocyanin subunit Y), and two proteins that are involved in metabolism (triosephosphate isomerase) and cell signaling (14-3-3 like protein), displayed significantly decreased expression levels. There was, however, an increase in the expression level of the ATP synthase beta subunit, a protein involved in energy balance. Transcription levels of ATP synthase beta subunit and 14-3-3 like protein were up- and down-regulated, respectively, in accord with the observed protein expression levels, but the alpha-2-macroglobulin transcript levels were significantly increased in contrast to the decreased protein expression levels. Interestingly, partial gene silencing of ATP synthase beta subunit revealed a high cumulative mortality of the knockdown shrimps (73.3%) and a dramatic reduction of the total hemocyte numbers in the survival shrimps. These altered proteins are likely to play essential roles in shrimp defense against the pathogenic bacterium V. harveyi. PMID:22302389

  18. Effect of the anti-lipopolysaccharide factor isoform 3 (ALFPm3) from Penaeus monodon on Vibrio harveyi cells.

    Science.gov (United States)

    Jaree, Phattarunda; Tassanakajon, Anchalee; Somboonwiwat, Kunlaya

    2012-12-01

    The anti-lipopolysaccharide factor isoform 3 from Penaeus monodon (ALFPm3) has previously been shown to have very active in vitro antimicrobial activity against a broad range of Gram-positive and Gram-negative bacteria, certain fungi and viruses, including known pathogens of P. monodon shrimp. With respect to the strong bactericidal effect on Gram-negative and Gram-positive bacteria, the ALFPm3 binds to their principal cell wall components, lipopolysaccharide (LPS) and lipoteichoic acid (LTA), with a high affinity. The aim of this study was, therefore, to reveal the effects of treating ALFPm3 on membrane of Vibrio harveyi, a P. monodon pathogenic Gram-negative bacterium. The recombinant (r)ALFPm3 protein was found to localize on the V. harveyi cells in vivo, followed by inducing membrane permeabilization and leakage of cytoplasmic components. Moreover, the effect of rALFPm3 treatment on the bacterial cell morphology was confirmed by scanning and transmission electron microscopy. Membrane disruption and damage, bleb and pore formation, and the leakage of cytoplasmic contents were all clearly observed. Taken together, these results suggested that ALFPm3 effectively kills bacteria through bacterial membrane permeabilization. PMID:23000267

  19. Grimontia indica AK16(T, sp. nov., isolated from a seawater sample reports the presence of pathogenic genes similar to Vibrio genus.

    Directory of Open Access Journals (Sweden)

    Aditya Singh

    Full Text Available Grimontia indica strain AK16(T sp. nov. is the type strain of G. indica sp. nov. a new species within the genus Grimontia. This strain, whose genome is described here, was isolated from seawater sample collected from southeast coast of Palk Bay, India. G. indica AK16(T is a Gram-negative, facultative aerobic rod shaped bacterium. There are only two other strains in the genus Grimontia one of which, Grimontia hollisae CIP 101886(T, is a reported human pathogen isolated from human stool sample while the other, 'Grimontia marina IMCC5001(T', was isolated from a seawater sample. As compared to the pathogenic strain Grimontia hollisae CIP 101886(T, the strain AK16(T lacks some genes for pathogenesis like the accessory colonization factors AcfA and AcfD, which are required for the colonization of the bacterium in the host body. While it carries some pathogenesis genes like OmpU, which are related to pathogenesis of Vibrio strains. This suggests that the life cycle of AK16(T may include some pathogenic interactions with marine animal(s, or it may be an opportunistic pathogen. Study of the Grimontia genus is important because of the severe pathogenic traits exhibited by a member of the genus with only three species reported in total. The study will provide some vital information which may be useful in future clinical studies on the genus.

  20. Temperature Change Induces the Expression of vuuA Encoding Vulnibactin Receptor and crp Encoding Cyclic AMP Receptor Protein in Vibrio vulnificus.

    Science.gov (United States)

    Kim, Choon-Mee; Ahn, Young-Joon; Kim, Seong-Jung; Yoon, Dae-Heung; Shin, Sung-Heui

    2016-07-01

    Upon entering the human body, Vibrio vulnificus, a gram-negative marine bacterium, must withstand a temperature change (TC) from 25 to 37 °C. This bacterium acquires iron mainly via the vulnibactin receptor (VuuA)-mediated iron uptake system (IUS), which is under the positive control of cyclic AMP receptor protein (CRP), a global regulator responsible for catabolite repression. In this study, we examined the effect of TC on the expression of vuuA and crp, and the reciprocal relation between VuuA-mediated IUS and CRP under iron-limited conditions. Iron limitation increased vuuA expression but decreased crp expression. TC resulted in increased vuuA and crp expression. A crp or vuuA mutation reciprocally decreased vuuA or crp expression. TC could increase vuuA or crp expression even in a crp- or vuuA-mutated background. These results indicate that TC increases the expression of both vuuA and crp by facilitating metabolism under iron-limited conditions, and that CRP and VuuA-mediated IUS interact coordinately toward optimal metabolism in V. vulnificus. PMID:27016238

  1. Lack of Outer Membrane Protein A Enhances the Release of Outer Membrane Vesicles and Survival of Vibrio cholerae and Suppresses Viability of Acanthamoeba castellanii

    Directory of Open Access Journals (Sweden)

    Soni Priya Valeru

    2014-01-01

    Full Text Available 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.

  2. Onderzoek pathogene vibrio soorten in Nederlandse mosselen en oesters in augustus en september 2003

    NARCIS (Netherlands)

    Aalberts, C.H.J.

    2003-01-01

    Naar aanleiding van de hoge weerstemperatuur in augustus 2003 zijn in de kweek- en verwatergebieden van mosselen en oesters in Nederland enkele monsters onderzocht op de aanwezigheid van voor de mens pathogene vibrio soorten. In geen van de 18 monsters is Vibrio parahaemolyticus, vulnificus of chole

  3. Bactericidal effect of lactoferrin and lactoferrin chimera against halophilic Vibrio parahaemolyticus

    NARCIS (Netherlands)

    N. Leon-Sicairos; A. Canizalez-Roman; M. de la Garza; M. Reyes-Lopez; J. Zazueta-Beltran; K. Nazmi; B. Gomez-Gil; J.G. Bolscher

    2009-01-01

    Infections caused by Vibrio parahaemolyticus, an halophilic member of the genus Vibrio, have increased globally in the last 5 years. Diarrhea caused by V. parahaemolyticus results from eating raw or undercooked seafood. The aim of this work was to investigate whether lactoferrin and some lactoferrin

  4. Biodegradation of heavy oils by halophilic bacterium

    Institute of Scientific and Technical Information of China (English)

    Ruixia Hao; Anhuai Lu

    2009-01-01

    A halophilic bacterial strain TM-1 was isolated from the reservoir of the Shengli oil field in East China. Strain TM-1, which was found to be able to degrade crude oils, is a gram-positive non-motile bacterium with a coccus shape that can grow at temperatures of up to 58 ℃ and in 18% NaCl solution. Depending on the culture conditions, the organism may occur in tetrads. In addition, strain TM-1 pro-duced acid from glucose without gas formation and was catalase-negative. Furthermore, strain TM-I was found to be a facultative aer-obe capable of growth under anaerobic conditions. Moreover, it produced butylated hydroxytoluene, 1,2-benzenedicarboxylic acid-bis ester and dibutyl phthalate and could use different organic substrates. Laboratory studies indicated that strain TM-1 affected different heavy oils by degrading various components and by changing the chemical properties of the oils. In addition, growth of the bacterium in heavy oils resulted in the loss of aromatic hydrocarbons, resins and asphaltenes, and enrichment with light hydrocarbons and an overall redistribution of these hydrocarbons.

  5. Ecología de Vibrio cholerae en relación al Fitoplancton y variables fisicoquímicas en ríos de Tucumán (Argentina Ecology of Vibrio cholerae in relation to phytoplankton and physico-chemical variables in rivers of Tucumán (Argentina

    Directory of Open Access Journals (Sweden)

    V. Mirande

    Full Text Available Vibrio cholerae muestra gran diversidad serológica en base a su antígeno somático O, conociéndose al menos 200 serogrupos. De éstos, solamente O1 y O139 son causantes de epidemias o pandemias. En Latinoamérica el serogrupo O1 reapareció en 1991, tras cien años de no presentar brotes en el continente. Esta bacteria sobrevive y se multiplica asociada al plancton, independientemente de la aparición de infecciones humanas. Desde la década del noventa, en Tucumán, se detectaron casos esporádicos de diarrea por Vibrio cholerae no-O1. El objetivo del presente trabajo fue estudiar la posible relación entre la presencia de especímenes de fitoplancton, variables fisicoquímicas y aislamientos de Vibrio cholerae en ríos de Tucumán. Se realizaron 18 campañas en los ríos Lules y Salí entre 2003-2005. Se estudiaron las variables fisicoquímicas del agua (pH, temperatura, conductividad y oxígeno disuelto, el fitoplancton (riqueza y frecuencia relativa y las cepas aisladas de V. cholerae. Los resultados evidenciaron diferencias en la calidad del agua, observándose períodos de anoxia en el río Salí. Las diatomeas sobresalieron en la mayoría de los meses y generalmente estuvieron en porcentajes superiores al 85 %. Sólo se aisló Vibrio cholerae no-O1, no-O139, detectándose más frecuentemente en los meses cálidos, con pH alcalino, aún con baja concentración de oxígeno.Vibrio cholerae shows a great serologic diversity in relation to his O somatic antigen and we know at least 200 serogroups. About these, only O1 and O139 are responsible of epidemics and pandemics. The serogroup O1 reemerged in Latin America in 1991 after being absent from the continent for nearly a century. This bacterium survives and grows up associated to plankton, independently of appearance of human infections. From 90 th decade, there were sporadic cases of diarrhea because of Vibrio cholerae O1 in Tucumán. The aims of this paper were to study the possible

  6. Unsupervised statistical identification of genomic islands using oligonucleotide distributions with application to Vibrio genomes

    Indian Academy of Sciences (India)

    Sanjay Nag; Raghunath Chatterjee; Keya Chaudhuri; Probal Chaudhuri

    2006-04-01

    Vibrio cholerae, Vibrio vulnificus, Vibrio parahaemolyticus and several other related Vibrio species show distinctly similar two-chromosomal genome organization. However, the modes of pathogenicity are very different among these species, and this is largely attributed to externally acquired genetic elements. We develop some statistical methods to determine these external genetic elements or genomic islands in genomes based on their differential oligonucleotide usage patterns compared to the rest of the genome. Genomic islands identified by these unsupervised statistical methods include integron and pathogenicity islands. After statistical determination of the genomic islands, we investigate their gene contents and their possible association with the pathogenic behaviour of the corresponding Vibrio species. These investigations lead to observations that are of evolutionary and biological significance.

  7. Vibrio ecology in PNW - The Ecology of Vibrio parahaemolyticus in the Pacific Northwest: Implications for risk assessment and early warning systems

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Over the past decade, there has been a significant increase in Vibrio parahaemolyticus-related gastroenteritis from the consumption of raw oysters harvested in...

  8. Temperature-dependent inhibition of opportunistic Vibrio pathogens by native coral commensal bacteria.

    Science.gov (United States)

    Frydenborg, Beck R; Krediet, Cory J; Teplitski, Max; Ritchie, Kim B

    2014-02-01

    Bacteria living within the surface mucus layer of corals compete for nutrients and space. A number of stresses affect the outcome of this competition. The interactions between native microorganisms and opportunistic pathogens largely determine the coral holobiont's overall health and fitness. In this study, we tested the hypothesis that commensal bacteria isolated from the mucus layer of a healthy elkhorn coral, Acropora palmata, are capable of inhibition of opportunistic pathogens, Vibrio shiloi AK1 and Vibrio coralliilyticus. These vibrios are known to cause disease in corals and their virulence is temperature dependent. Elevated temperature (30 °C) increased the cell numbers of one commensal and both Vibrio pathogens in monocultures. We further tested the hypothesis that elevated temperature favors pathogenic organisms by simultaneously increasing the fitness of vibrios and decreasing the fitness of commensals by measuring growth of each species within a co-culture over the course of 1 week. In competition experiments between vibrios and commensals, the proportion of Vibrio spp. increased significantly under elevated temperature. We finished by investigating several temperature-dependent mechanisms that could influence co-culture differences via changes in competitive fitness. The ability of Vibrio spp. to utilize glycoproteins found in A. palmata mucus increased or remained stable when exposed to elevated temperature, while commensals' tended to decrease utilization. In both vibrios and commensals, protease activity increased at 30 °C, while chiA expression increased under elevated temperatures for Vibrio spp. These results provide insight into potential mechanisms through which elevated temperature may select for pathogenic bacterial dominance and lead to disease or a decrease in coral fitness. PMID:24370863

  9. Ratoon stunting disease of sugarcane: isolation of the causal bacterium.

    Science.gov (United States)

    Davis, M J; Gillaspie, A G; Harris, R W; Lawson, R H

    1980-12-19

    A small coryneform bacterium was consistently isolated from sugarcane with ratoon stunting disease and shown to be the causal agent. A similar bacterium was isolated from Bermuda grass. Both strains multiplied in sugarcane and Bermuda grass, but the Bermuda grass strain did not incite the symptoms of ratoon stunting disease in sugarcane. Shoot growth in Bermuda grass was retarded by both strains. PMID:17817853

  10. In vitro synergism between cefotaxime and minocycline against Vibrio vulnificus.

    OpenAIRE

    Chuang, Y. C.; Liu, J W; Ko, W C; Lin, K. Y.; Wu, J.J.; Huang, K Y

    1997-01-01

    We conducted time-kill studies to evaluate the inhibitory activities of either cefotaxime or minocycline alone and the two drugs in combination against a clinical strain of Vibrio vulnificus. The MICs of cefotaxime and minocycline were 0.03 and 0.06 microg/ml, respectively. When approximately 5 x 10(5) CFU of V. vulnificus per ml was incubated with cefotaxime at 0.03 or 0.05 microg/ml, the bacterial growth was inhibited during the initial 2 and 8 h, respectively. Thereafter, V. vulnificus reg...

  11. Induction of Protease Activity in Vibrio anguillarum by Gastrointestinal Mucus

    OpenAIRE

    Denkin, Steven M.; Nelson, David R.

    1999-01-01

    The effect of gastrointestinal mucus on protease activity in Vibrio anguillarum was investigated. Protease activity was measured by using an azocasein hydrolysis assay. Cells grown to stationary phase in mucus (200 μg of mucus protein/ml) exhibited ninefold-greater protease activity than cells grown in Luria-Bertani broth plus 2% NaCl (LB20). Protease induction was examined with cells grown in LB20 and resuspended in mucus, LB20, nine-salts solution (NSS [a carbon-, nitrogen-, and phosphorus-...

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

    DEFF Research Database (Denmark)

    Tan, Demeng; Gram, Lone; Middelboe, Mathias

    2014-01-01

    Vibrio anguillarum is an important pathogen in aquaculture, responsible for the disease vibriosis in many fish and invertebrate species. Disease control by antibiotics is a concern due to potential development and spread of antibiotic resistance. The use of bacteriophages to control the pathogen...... may offer a non-antibiotic-based approach to reduce vibriosis. A detailed understanding of the phage-host interaction is needed to evaluate the potential of phages to control the pathogen. In this study, we examined the diversity and interactions of 11 vibriophages, 24 V. anguillarum strains, and 13...

  13. Vibrio harveyi Nitroreductase Is Also a Chromate Reductase

    OpenAIRE

    Kwak, Young Hak; Lee, Dong Seok; Kim, Han Bok

    2003-01-01

    The chromate reductase purified from Pseudomonas ambigua was found to be homologous with several nitroreductases. Escherichia coli DH5α and Vibrio harveyi KCTC 2720 nitroreductases were chosen for the present study, and their chromate-reducing activities were determined. A fusion between glutathione S-transferase (GST) and E. coli DH5α NfsA (GST-EcNfsA), a fusion between GST and E. coli DH5α NfsB (GST-EcNfsB), and a fusion between GST and V. harveyi KCTC 2720 NfsA (GST-VhNfsA) were prepared f...

  14. Broth medium for enrichment of Vibrio fluvialis from the environment.

    OpenAIRE

    Nishibuchi, M; Roberts, N C; Bradford, H B; Seidler, R J

    1983-01-01

    A medium was designed for the enrichment and enumeration of Vibrio fluvialis from environmental samples. The medium contains 1% peptone plus 4% sodium chloride and 5 micrograms of novobiocin per ml, pH 8.5. This V. fluvialis enrichment medium (FEM) was tested, in comparison with alkaline peptone (AP), in field samplings. A total of 177 samples (estuarine waters and sediment, sewage, and crabs) collected over a 14-month period were examined with FEM and with AP broth. Results showed that FEM w...

  15. Fluctuation-Enhanced Sensing of Bacterium Odors

    CERN Document Server

    Chang, Hung-Chih; King, Maria D; Kwan, Chiman

    2009-01-01

    The goal of this paper is to explore the possibility to detect and identify bacteria by sensing their odor via fluctuation-enhanced sensing with commercial Taguchi sensors. The fluctuations of the electrical resistance during exposure to different bacterial odors, Escherichia coli and anthrax-surrogate Bacillus subtilis, have been measured and analyzed. In the present study, the simplest method, the measurement and analysis of power density spectra was used. The sensors were run in the normal heated and the sampling-and-hold working modes, respectively. The results indicate that Taguchi sensors used in these fluctuation-enhanced modes are effective tools of bacterium detection and identification even when they are utilizing only the power density spectrum of the stochastic sensor signal.

  16. Toxic factors of Vibrio strains pathogenic to shrimp.

    Science.gov (United States)

    Goarant, C; Herlin, J; Brizard, R; Marteau, A L; Martin, C; Martin, B

    2000-03-14

    Vibriosis is a major disease problem in shrimp aquaculture. 'Syndrome 93' is a seasonal juvenile vibriosis caused by Vibrio penaeicida which affects Litopenaeus stylirostris in grow-out ponds in New Caledonia. This study assessed the toxic activities of extracellular products (ECPs) from V. penaeicida, V. alginolyticus and V. nigripulchritudo using in vivo injections in healthy juvenile L. stylirostris (= Penaeus stylirostris) and in vitro assays on shrimp primary cell cultures and the fish cell line epithelioma papulosum cyprini (EPC). Toxic effects of ECPs were demonstrated for all pathogenic Vibrio strains tested both in vivo and in vitro, but for shrimp only; no effect was observed on the fish cell line. ECP toxicity for New Caledonian V. penaeicida was found only after cultivation at low temperature (20 degrees C) and not at higher temperature (30 degrees C). This points to the fact that 'Syndrome 93' episodes are triggered by temperature drops. The assays used here demonstrate the usefulness of primary shrimp cell cultures to study virulence mechanisms of shrimp pathogenic bacteria. PMID:10782343

  17. Invariant recognition of polychromatic images of Vibrio cholerae 01

    Science.gov (United States)

    Alvarez-Borrego, Josue; Mourino-Perez, Rosa R.; Cristobal, Gabriel; Pech-Pacheco, Jose L.

    2002-04-01

    Cholera is an acute intestinal infectious disease. It has claimed many lives throughout history, and it continues to be a global health threat. Cholera is considered one of the most important emergence diseases due its relation with global climate changes. Automated methods such as optical systems represent a new trend to make more accurate measurements of the presence and quantity of this microorganism in its natural environment. Automatic systems eliminate observer bias and reduce the analysis time. We evaluate the utility of coherent optical systems with invariant correlation for the recognition of Vibrio cholerae O1. Images of scenes are recorded with a CCD camera and decomposed in three RGB channels. A numeric simulation is developed to identify the bacteria in the different samples through an invariant correlation technique. There is no variation when we repeat the correlation and the variation between images correlation is minimum. The position-, scale-, and rotation-invariant recognition is made with a scale transform through the Mellin transform. The algorithm to recognize Vibrio cholerae O1 is the presence of correlation peaks in the green channel output and their absence in red and blue channels. The discrimination criterion is the presence of correlation peaks in red, green, and blue channels.

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

    Science.gov (United States)

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

    2014-12-01

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

  19. Vibrio harveyi effect under survival of Litopenaeus vannamei larvae

    Directory of Open Access Journals (Sweden)

    Gabriel Aguirre-Guzmán

    2013-06-01

    Full Text Available The culture of aquatic organisms show a high relevance in the human feeding and the culture activities can create artificial conditions that increase the growth and selection of specific bacteria. Vibrio species are normal bacteria’s from microflora of penaeid shrimp, those are opportunistic pathogens that can take advantage of the ecological changes generated for the culture of aquatic organisms and which may cause diseases, low survival and economic losses in the shrimp production. The aim of this research was to determine the variation in the survival of different larval substages (nauplius, zoea I-III, mysis I-III and postlarvae 1, of Pacific white shrimp Litopenaeus vannamei exposed at three doses [103 , 105 , and 107 colony-forming unit (CFU ml-1 [ of V. harveyi, by immersion (30 min as infection method. This species generated a significant low survival in larvae (p < 0.05 only in high doses (105 and 107 CFU ml-1 , where higher doses show the lowest values of survival. Larval substages and postlarvae 1 of shrimp showed sensitivity associate to the increase of Vibrio doses and this sensitivity decreased with the growth of larval substages and postlarvae 1. This information has high significance for the fisheries and aquaculture industry, which help to generate strategies to reduce the effects of V. harveyi with positive effect in growth and survival of the shrimp larvae and postlarvae 1.

  20. Parallel quorum sensing signaling pathways in Vibrio cholerae.

    Science.gov (United States)

    Jung, Sarah A; Hawver, Lisa A; Ng, Wai-Leung

    2016-05-01

    Quorum sensing (QS) is a microbial signaling process for monitoring population density and complexity. Communication among bacterial cells via QS relies on the production, secretion, and detection of small molecules called autoinducers. Many bacteria have evolved their QS systems with different network architectures to incorporate information from multiple signals. In the human pathogen Vibrio cholerae, at least four parallel signaling pathways converge to control the activity of a single regulator to modulate its QS response. By integrating multiple signal inputs, it is believed that Vibrio species can survey intra-species, intra-genus, and inter-species populations and program their gene expression accordingly. Our recent studies suggest that this "many-to-one" circuitry is also important for maintaining the integrity of the input-output relationship of the system and minimizes premature commitment to QS due to signal perturbation. Here we discuss the implications of this specific parallel network setup for V. cholerae intercellular communication and how this system arrangement affects our approach to manipulate the QS response of this clinically important pathogen. PMID:26545759

  1. Vibrio fischeri-derived outer membrane vesicles trigger host development.

    Science.gov (United States)

    Aschtgen, Marie-Stephanie; Wetzel, Keith; Goldman, William; McFall-Ngai, Margaret; Ruby, Edward

    2016-04-01

    Outer membrane vesicles (OMV) are critical elements in many host-cell/microbe interactions. Previous studies of the symbiotic association between Euprymna scolopes and Vibrio fischeri had shown that within 12 h of colonizing crypts deep within the squid's light organ, the symbionts trigger an irreversible programme of tissue development in the host. Here, we report that OMV produced by V. fischeri are powerful contributors to this process. The first detectable host response to the OMV is an increased trafficking of macrophage-like cells called haemocytes into surface epithelial tissues. We showed that exposing the squid to other Vibrio species fails to induce this trafficking; however, addition of a high concentration of their OMV, which can diffuse into the crypts, does. We also provide evidence that tracheal cytotoxin released by the symbionts, which can induce haemocyte trafficking, is not part of the OMV cargo, suggesting two distinct mechanisms to induce the same morphogenesis event. By manipulating the timing and localization of OMV signal delivery, we showed that haemocyte trafficking is fully induced only when V. fischeri, the sole species able to reach and grow in the crypts, succeeds in establishing a sustained colonization. Further, our data suggest that the host's detection of OMV serves as a symbiotic checkpoint prior to inducing irreversible morphogenesis. PMID:26399913

  2. Extracellular proteolytic enzymes produced by human pathogenic Vibrio species

    Directory of Open Access Journals (Sweden)

    Shin-IchiMiyoshi

    2013-11-01

    Full Text Available Bacteria in the genus Vibrio produce extracellular proteolytic enzymes to obtain nutrients via digestion of various protein substrates. However, the enzymes secreted by human pathogenic species have been documented to modulate the bacterial virulence. Several species including Vibrio cholerae and V. vulnificus are known to produce thermolysin-like metalloproteases termed vibriolysin. The vibriolysin from V. vulnificus, a causative agent of serious systemic infection, is a major toxic factor eliciting the secondary skin damage characterized by formation of the hemorrhagic brae. The vibriolysin from intestinal pathogens may play indirect roles in pathogenicity because it can activate protein toxins and hemagglutinin by the limited proteolysis and can affect the bacterial attachment to or detachment from the intestinal surface by degradation of the mucus layer. Two species causing wound infections, V. alginolyticus and V. parahaemolyticus, produce another metalloproteases so-called collagenases. Although the detailed pathological roles have not been studied, the collagenase is potent to accelerate the bacterial dissemination through digestion of the protein components of the extracellular matrix. Some species produce cymotrypsin-like serine proteases, which may also affect the bacterial virulence potential. The intestinal pathogens produce sufficient amounts of the metalloprotease at the small intestinal temperature; however, the metalloprotease production by extra-intestinal pathogens is much higher around the body surface temperature. On the other hand, the serine protease is expressed only in the absence of the metalloprotease.

  3. Application of Alternative Technologies to Eliminate Vibrios spp. in Raw Oysters

    OpenAIRE

    Hu, Xiaopei

    2004-01-01

    High pressure processing (HPP) and gamma irradiation were applied to inactivate Vibrio vulnificus (MO624) and Vibrio parahaemolyticus (O3:K6 TX2103) in pure culture and in inoculated live oysters. Vibrio pure culture and inoculated oysters were exposed to pressures of 207 MPa (30 kpsi) to 552 MPa (80 kpsi) for 0 min to maximum of 20 min. More than 5.4 log reductions of V. vulnificus occurred at 345 MPa for 0 min in oysters; 345 MPa for 2 min can achieve 4 log reductions on V. parahaemolyticus...

  4. Antimicrobial effect of dietary oregano essential oil against Vibrio bacteria in shrimps

    Directory of Open Access Journals (Sweden)

    Gracia-Valenzuela M.H.

    2014-01-01

    Full Text Available The effect of dietary oregano essential oils on the growth of Vibrio bacteria in shrimps was evaluated. Shrimps were fed: (i food with oregano oil with a high level of thymol; (ii food with oregano oil with a high level of carvacrol, and (iii food without oregano oil (the control. The animals were infected by three species of Vibrio (vulnificus, parahaemolyticus and cholerae. The microbial counts of Vibrio species were significantly lower (p <0.05 in tissues from animals whose food was supplemented with oregano oil. We concluded that dietary supplementation of shrimps with oregano oil provides antimicrobial activity into the body of the penaeids.

  5. Detection of Pathogenic Vibrio spp. in Shellfish by Using Multiplex PCR and DNA Microarrays

    OpenAIRE

    Panicker, Gitika; Call, Douglas R.; Krug, Melissa J.; Bej, Asim K.

    2004-01-01

    This study describes the development of a gene-specific DNA microarray coupled with multiplex PCR for the comprehensive detection of pathogenic vibrios that are natural inhabitants of warm coastal waters and shellfish. Multiplex PCR with vvh and viuB for Vibrio vulnificus, with ompU, toxR, tcpI, and hlyA for V. cholerae, and with tlh, tdh, trh, and open reading frame 8 for V. parahaemolyticus helped to ensure that total and pathogenic strains, including subtypes of the three Vibrio spp., coul...

  6. Antagonistic Activities of Purple Non-sulfur Bacterial Extracts Against Antibiotic Resistant Vibrio sp.

    Directory of Open Access Journals (Sweden)

    Chandrasekaran, R.

    2011-01-01

    Full Text Available Solvent extracts of native purple non-sulfur bacterial (PNSB isolates from the effluents of brackish shrimp culture ponds, near Nagapattinam coast (South India were evaluated for antibacterial activity by the disc diffusion method. Best results were shown by the chloroform extracts against oxytetracycline resistant Vibrio harveyi and Vibrio fischerii. Among the purple non-sulfur bacterial isolates, Rhodobacter sphaeroides, showed maximum antagonistic activity. The findings suggest that the antagonistic extracts from Rba. sphaeroides could be used as an effective antibiotic in controlling Vibrio spp., in aquaculture systems.

  7. Genetic characterization of DNA region containing the trh and ure genes of Vibrio parahaemolyticus.

    Science.gov (United States)

    Park, K S; Iida, T; Yamaichi, Y; Oyagi, T; Yamamoto, K; Honda, T

    2000-10-01

    We have demonstrated that possession of the gene for thermostable direct hemolysin-related hemolysin (trh) coincides with the presence of the urease gene among clinical Vibrio parahaemolyticus strains and that the location of the two genes are in close proximity on the chromosome. Here, we cloned and sequenced the 15,754-bp DNA region containing the trh gene and the gene cluster for urease production from the chromosome of clinical V. parahaemolyticus (TH3996). We found 16 open reading frames (ORFs) and a lower G+C content (41%) compared with the total genome of this bacterium (46 to 47%). The ure cluster consisted of eight genes, namely, ureDABCEFG and ureR. ureR was located 5.2 kb upstream of the other seven genes in the opposite direction. The genetic organization and sequences of the ure genes resembled those found in Proteus mirabilis. Between ureR and the other ure genes, there were five ORFs, which are homologous with the nickel transport operon (nik) of Escherichia coli. We disrupted each of the ureR, ureC, and nikD genes in TH3996 by homologous recombination and analyzed the phenotype of the mutants. In the presence of urea these mutant strains had dramatically less urease activity than the strain they were derived from. Disruption of ureR, nikD, or ureC, however, had no effect on TRH production. The DNA region containing the trh, nik, and ure genes was found in only trh-positive strains and not in Kanagawa phenomenon-positive and environmental V. parahaemolyticus strains. At the end of the region, an insertion sequence-like element existed. These results suggest that the DNA region was introduced into V. parahaemolyticus in the past through a mechanism mediated by insertion sequences. This is the first reported case that the genes for an ATP-binding cassette-type nickel transport system, which may play a role in nickel transport through bacterial cytoplasmic membrane, are located adjacent to the ure cluster on the genome of an organism. PMID:10992480

  8. Aspects of vibrio parahaemolyticus(SAK) in fish preservation by irradiation 1. The presence of vibrio parahaemolyticus(SAK) in coastal areas of Sumatra and Java

    International Nuclear Information System (INIS)

    A study was carried out on the presence of vibrio parahaemolyticus in samples of sediment and seafoods originating from the eastern coast of Sumatra and the north coastal areas of Java. In a total of 2.434 samples of sediment and seafoods, 79 (3,3%) were found to contain vibrio parahaemolyticus. Among the 467 sediment samples, 1.650 fish, 133 shellfish, 123 shrimps, and 61 crab samples, 22 (4.7%), 41 (2.5%), 12 (9.0%), 2 (1,6%) and 2 (3.3%) were positive for vibrio parahaemolyticus, respectively. Based on the sampling areas, the high incidence of vibrio parahaemolyticus was found in samples collected from Riau (5.4%), while the samples from East Java was only about 0.4%. The contamination level of vibrio parahaemolyticus in samples collected from coastal areas of Sumatra and Java is relatively lower compared with the data obtained from some other coastal areas in the United States and Japan. (author)

  9. Genome Sequence of the Soil Bacterium Janthinobacterium sp. KBS0711

    OpenAIRE

    Shoemaker, William R.; Muscarella, Mario E.; Lennon, Jay T

    2015-01-01

    We present a draft genome of Janthinobacterium sp. KBS0711 that was isolated from agricultural soil. The genome provides insight into the ecological strategies of this bacterium in free-living and host-associated environments.

  10. Experimental Reservoirs of Human Pathogens: The Vibrio Cholerae Paradigm (7th Annual SFAF Meeting, 2012)

    Energy Technology Data Exchange (ETDEWEB)

    Colwell, Rita [University of Maryland

    2012-06-01

    Rita Colwell on "Experimental Reservoirs of Human Pathogens: The Vibrio cholerae paradigm" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.

  11. Prevalence and diversity of Aeromonas and Vibrio spp. in coastal waters of Southern Italy

    DEFF Research Database (Denmark)

    Dumontet, S.; Krovacek, K.; Svenson, S.B.;

    2000-01-01

    A survey was undertaken to examine sea water and sediment for the presence of Vibrio and Aeromonas spp. along approximately 900 km of coast in Southern Italy during early and late summer. A quantitative analysis was also done to evaluate the water fecal contamination at the stations examined. The...... results indicate that all the investigated areas were submitted to a wide spatial fluctuation of fecal contamination and that Vibrio and Aeromonas spp. were present in both high and low fecal-contaminated stations. Sixty two percent of the investigated samples were positive for Aeromonas spp., while 42......% of samples were positive for Vibrio spp. It was interesting to note that 38% of the positive stations for both Aeromonas and Vibrio spp. showed a fecal coliform contamination of water at <10(2) cells 100 ml(-1). Thus, these findings support the hypothesis that the bacterial indicators (such as fecal...

  12. Color correlation for the recognition of Vibrio cholerae O1 in seawater

    Science.gov (United States)

    Mourino-Perez, Rosa R.; Alvarez-Borrego, Josue

    1999-07-01

    Application of color correlation optical systems for the recognition of Vibrio cholerae 01 in seawater samples with matched filters and phase only filters recorded in holographic plates in three channels (RGB).

  13. Uptake of Vibrio cholerae Biotype eltor from Contaminated Water by Water Hyacinth (Eichornia crassipes)

    OpenAIRE

    Spira, William M.; Huq, Anwarul; Ahmed, Qazi Shafi; Saeed, Yusuf A.

    1981-01-01

    Vibrio cholerae biotype eltor appears to concentrate on the surface of the water hyacinth (Eichornia crassipes), thereby enhancing its survival and its potential for transmission through waterways of cholera-endemic regions such as Bangladesh.

  14. Distribution of putative virulence genes and antimicrobial drug resistance in Vibrio harveyi

    Digital Repository Service at National Institute of Oceanography (India)

    Parvathi, A.; Mendez, D.; Anto, C.

    environments for understanding the distribution of putative virulence genes and antimicrobial drug resistance. The putative genes targeted for PCR detection included four reversible toxin (Rtx)/hemolysin genes, a gene encoding homologue of Vibrio cholerae...

  15. Genome Sequence of Vibrio cholerae G4222, a South African Clinical Isolate

    OpenAIRE

    le Roux, Wouter J.; Chan, Wai Yin; De Maayer, Pieter; Venter, Stephanus N.

    2013-01-01

    Vibrio cholerae, a Gram-negative pathogen autochthonous to the aquatic environment, is the causative agent of cholera. Here, we report the complete genome sequence of V. cholerae G4222, a clinical isolate from South Africa.

  16. Pulmonary Cholera Due to Infection with a Non-O1 Vibrio cholerae Strain

    OpenAIRE

    Shannon, Jack D.; Kimbrough, Robert C.

    2006-01-01

    We present 2 cases of primary pulmonary non-O1 Vibrio cholerae infection. We believe that these are the first documented cases of primary pulmonary infection due to this organism from a freshwater source.

  17. Gauze Filtration and Enrichment Procedures for Recovery of Vibrio cholerae from Contaminated Waters

    OpenAIRE

    Spira, W M; Ahmed, Q S

    1981-01-01

    Gauze filtration followed by 18-h enrichment in alkaline bile-peptone water is a simple, inexpensive, and efficient method for isolation Vibrio cholerae biotype eltor from contaminated surface waters.

  18. Trichloroethylene Biodegradation by a Methane-Oxidizing Bacterium

    OpenAIRE

    Little, C. Deane; Palumbo, Anthony V; Herbes, Stephen E.; Lidstrom, Mary E.; Tyndall, Richard L.; Gilmer, Penny J.

    1988-01-01

    Trichloroethylene (TCE), a common groundwater contaminant, is a suspected carcinogen that is highly resistant to aerobic biodegradation. An aerobic, methane-oxidizing bacterium was isolated that degrades TCE in pure culture at concentrations commonly observed in contaminated groundwater. Strain 46-1, a type I methanotrophic bacterium, degraded TCE if grown on methane or methanol, producing CO2 and water-soluble products. Gas chromatography and 14C radiotracer techniques were used to determine...

  19. Prevalence and Antimicrobial Resistance of Vibrio spp. in Retail and Farm Shrimps in Ecuador.

    Science.gov (United States)

    Sperling, L; Alter, T; Huehn, S

    2015-11-01

    The aim of this study was to investigate the prevalence of Vibrio spp. in shrimp at retail and in shrimp farms in Ecuador and to determine the antimicrobial agent resistance patterns of farm isolates. The presence of genes linked to early mortality syndrome (EMS) or acute hepatopancreatic necrosis disease (AHPND) also was evaluated. Vibrio spp. were isolated from retail shrimps in Cuenca, Ecuador, and farm shrimps originating from provinces El Oro and Guayas, Ecuador. A total of 229 shrimp samples were collected, of which 71 originated from retail markets in Cuenca and 158 came from shrimp farms. Overall, 219 (95.6%) samples tested positive for Vibrio spp. Vibrio parahaemolyticus (80.8%) was the most common species detected, followed by Vibrio alginolyticus (50.2%), Vibrio cholerae (11.3%), and Vibrio vulnificus (3.5%). None of the V. parahaemolyticus isolates carried the virulence-associated tdh and trh genes. In V. parahaemolyticus shrimp farm isolates, high resistance was found to ampicillin (92.2%), and intermediate resistance was found to tetracycline (51.3%) and amikacin (22.1%). Of the V. parahaemolyticus strains, 68 were resistant to at least three antimicrobial agents, and 2 were resistant to seven antimicrobial agents simultaneously. Up to 18 resistant isolates were found for V. alginolyticus, whereas V. vulnificus and V. cholerae isolates were more susceptible. None of the V. parahaemolyticus isolates carried the EMS-AHPND plasmid. The results of this study revealed the ubiquitous occurrence of Vibrio spp. in shrimps at retail and on shrimp farms in Ecuador. PMID:26555534

  20. Acetone Formation in the Vibrio Family: a New Pathway for Bacterial Leucine Catabolism

    OpenAIRE

    Nemecek-Marshall, Michele; Wojciechowski, Cheryl; William P. Wagner; Fall, Ray

    1999-01-01

    There is current interest in biological sources of acetone, a volatile organic compound that impacts atmospheric chemistry. Here, we determined that leucine-dependent acetone formation is widespread in the Vibrionaceae. Sixteen Vibrio isolates, two Listonella species, and two Photobacterium angustum isolates produced acetone in the presence of l-leucine. Shewanella isolates produced much less acetone. Growth of Vibrio splendidus and P. angustum in a fermentor with controlled aeration revealed...

  1. Studies on luminous, Vibrio harveyi associated with shrimp culture system rearing Panaeus monodon

    Digital Repository Service at National Institute of Oceanography (India)

    Kannapiran, E.; Ravindran, J.; Chandrasekar, R.; Kalaiarasi, A.

    and V. harveyi density were low at that time. Vaseeharan and Ramasamy (2003) also reported that the growth of pathogenic V. harveyi isolated from Penaeus monodon with black gill disease was controlled by non-pathogenic B. subtilis BT23 as probiotic...: Vibrios associated with Penaeus chinensis (Crustacea: Decapoda) larvae and post-larvae in Chinese shrimp hatcheries. Aquaculture 169, 121-132 (1998). Vaseeharan, B. and P. Ramasamy: Control of pathogenic Vibrio spp. by Bacillus subtilis BT23, a possible...

  2. Vibrio alginolyticus Associated Chronic Myringitis Acquired in Mediterranean Waters of Turkey

    OpenAIRE

    Burak Ekrem Citil; Serhan Derin; Funda Sankur; Murat Sahan; Mahmut Ugur Citil

    2015-01-01

    Vibrio alginolyticus was originally classified as biotype 2 of Vibrio parahaemolyticus. Most clinical isolates are recovered from superficial wounds or the external ear infections. V. alginolyticus is acknowledged to be nearly nonpathogenic in humans. The reason for presence of V. alginolyticus’s virulence is uncertain. We describe a chronic myringitis case in a 47-year-old female due to V. alginolyticus. According to her anamnesis, it was detected that she had sea bathing history in Mugla Co...

  3. Natural transformation of Vibrio fischeri requires tfoX and tfoY

    OpenAIRE

    Pollack-Berti, Amber; Wollenberg, Michael S.; Ruby, Edward G.

    2010-01-01

    Recent evidence has indicated that natural genetic transformation occurs in Vibrio cholerae, and that it requires both induction by chitin oligosaccharides, like chitohexaose, and expression of a putative regulatory gene designated tfoX. Using sequence and phylogenetic analyses we have found two tfoX paralogues in all sequenced genomes of the genus Vibrio. Like V. cholerae, when grown in chitohexaose, cells of V. fischeri are able to take up and incorporate exogenous DNA. Chitohexaose-indepen...

  4. Inferring the Evolutionary History of Vibrios by Means of Multilocus Sequence Analysis▿ †

    OpenAIRE

    Sawabe, Tomoo; Kita-Tsukamoto, Kumiko; Thompson, Fabiano L

    2007-01-01

    We performed the first broad study aiming at the reconstruction of the evolutionary history of vibrios by means of multilocus sequence analysis of nine genes. Overall, 14 distinct clades were recognized using the SplitsTree decomposition method. Some of these clades may correspond to families, e.g., the clades Salinivibrio and Photobacteria, while other clades, e.g., Splendidus and Harveyi, correspond to genera. The common ancestor of all vibrios was estimated to have been present 600 million...

  5. Antagonistic Activities of Purple Non-sulfur Bacterial Extracts Against Antibiotic Resistant Vibrio sp.

    OpenAIRE

    Chandrasekaran, R.; Ashok Kumar, G. V.

    2011-01-01

    Solvent extracts of native purple non-sulfur bacterial (PNSB) isolates from the effluents of brackish shrimp culture ponds, near Nagapattinam coast (South India) were evaluated for antibacterial activity by the disc diffusion method. Best results were shown by the chloroform extracts against oxytetracycline resistant Vibrio harveyi and Vibrio fischerii. Among the purple non-sulfur bacterial isolates, Rhodobacter sphaeroides, showed maximum antagonistic activity. The findings suggest that the...

  6. FK phage for differentiating the classical and El T or groups of Vibrio cholerae.

    OpenAIRE

    Takeya, K; Otohuji, T; Tokiwa, H

    1981-01-01

    A new vibrio-infecting phage (FK phage) isolated from sewage lysed all strains of Vibrio cholerae biovar cholerae, whereas all strains of V. cholerae biovar El Tor were resistant to it. FK phage was entirely different from Mukerjee group IV phage in morphology and antigenicity. In addition to group IV phage, the use of FK phage will be useful in the examination and typing of V. cholerae.

  7. Neuraminidase production by Vibrio cholerae O1 and other diarrheagenic bacteria.

    OpenAIRE

    Kabir, S; Ahmad, N.; Ali, S.

    1984-01-01

    Vibrio cholerae O1 strains belonging to both biotypes (classical and El Tor) and both serotypes (Ogawa and Inaba) produced neuraminidase which was released rather than cell bound. Classical strains made more neuraminidase than did El Tor strains. About one-third of V. cholerae non-O1 strains and one-fourth of Aeromonas hydrophila strains were neuraminidase positive. Strains of enterotoxigenic Escherichia coli, Vibrio parahaemolyticus, and Shigella spp. did not produce detectable neuraminidase.

  8. Taxonomic characterization of the cellulose-degrading bacterium NCIB 10462

    Energy Technology Data Exchange (ETDEWEB)

    Dees, C.; Ringleberg, D.; Scott, T.C. [Oak Ridge National Lab., TN (United States); Phelps, T. [Univ. of Tennessee, Knoxville, TN (United States)

    1994-06-01

    The gram negative cellulase-producing bacterium NCIB 10462 has been previously named Pseudomonas fluorescens subsp. or var. cellulosa. Since there is renewed interest in cellulose-degrading bacteria for use in bioconversion of cellulose to chemical feed stocks and fuels, we re-examined the characteristics of this microorganism to determine its proper taxonomic characterization and to further define it`s true metabolic potential. Metabolic and physical characterization of NCIB 10462 revealed that this was an alkalophilic, non-fermentative, gram negative, oxidase positive, motile, cellulose-degrading bacterium. The aerobic substrate utilization profile of this bacterium was found to have few characteristics consistent with a classification of P. fluorescens with a very low probability match with the genus Sphingomonas. Total lipid analysis did not reveal that any sphingolipid bases are produced by this bacterium. NCIB 10462 was found to grow best aerobically but also grows well in complex media under reducing conditions. NCIB 10462 grew slowly under full anaerobic conditions on complex media but growth on cellulosic media was found only under aerobic conditions. Total fatty acid analysis (MIDI) of NCIB 10462 failed to group this bacterium with a known pseudomonas species. However, fatty acid analysis of the bacteria when grown at temperatures below 37{degrees}C suggest that the organism is a pseudomonad. Since a predominant characteristic of this bacterium is it`s ability to degrade cellulose, we suggest it be called Pseudomonas cellulosa.

  9. Acute Otitis due to Vibrio fluvialis after Swimming

    Directory of Open Access Journals (Sweden)

    Ping-Jen Chen

    2012-01-01

    Full Text Available A 40-year-old female presented with purulent exudate through the left auditive duct and pain in the left ear region, which intensified during mastication. After collection of the pus from the left ear lesion, amoxicillin-clavulanic acid for seven days was prescribed for a presumed diagnosis of acute otitis. Four days later, the pus culture grew V. fluvialis which is further identified by API 20E identification system (bioMérieux. Following the successful completion of a course of antibiotics, the patient recovered completely and without complication. To the best of our knowledge, this is the first case of Vibrio fluvialis otitis after swimming in an immunocompetent patient.

  10. Iron and virulence in the zoonotic pathogen Vibrio vulnificus

    OpenAIRE

    Pajuelo Gámez, David

    2014-01-01

    Vibrio vulnificus es un patógeno humano emergente que es autóctono de ecosistemas acuáticos salobres de climas templados, tropicales y subtropicales. La especie se subdivide en 3 biotipos (Bt), de los cuales el Bt2 contiene un grupo de cepas que, además de poder infectar al hombre, pueden causar infecciones en peces. Este grupo es un complejo clonal serológicamente homogéneo que denominamos serovar E o serovar zoonótica (VvBt2SerE). Como patógeno humano, VvBt2SerE causa casos esporádicos de i...

  11. Survival of Vibrio cholerae O1 on fomites

    DEFF Research Database (Denmark)

    Farhana, Israt; Hossain, Zenat Zebin; Tulsiani, Suhella Mohan;

    2016-01-01

    It is well established that the contamination sources of cholera causing bacteria, Vibrio cholerae, are water and food, but little is known about the transmission role of the fomites (surfaces that can carry pathogens) commonly used in households. In the absence of appropriate nutrients or growth...... conditions on fomites, bacteria have been known to assume a viable but non-culturable (VBNC) state after a given period of time. To investigate whether and when V. cholerae O1 assumes such a state, this study investigated the survival and viable quantification on a range of fomites such as paper, wood, glass......, plastic, cloth and several types of metals under laboratory conditions. The fomites were inoculated with an outbreak strain of V. cholerae and its culturability was examined by drop plate count method at 30 min intervals for up to 6 h. For molecular detection, the viable/dead stain ethidium monoazide (EMA...

  12. Detection of pathogenic Vibrio parahaemolyticus in Butrinti Lagoon shellfish

    Directory of Open Access Journals (Sweden)

    FATMIRA SHEHU

    2014-06-01

    Full Text Available Given the considerable public health implications, monitoring of V. parahaemolyticus in shellfish is crucial. The 50 shellfish samples from Butrinti Lagoon showed bacteriological parameters, Salmonella and E. coli, according to Commission Regulation EC No. 2073/2005 on microbiological criteria for foodstuffs. In particular, Salmonella was absent in 25 g and E. coli less 230/100 g of flesh and intra-valvular liquid. The PCRs performed on enrichment broth from each sample gave positive results for V. parahaemolyticus in 45/50 shellfish samples. The TDH virulence factor was detected in 15/45 samples only, whereas TRH factor was not highlighted at all. The results confirmed the need for a specific shellfish inspection plan to detect the presence of Vibrio species and viruses in order to eliminate public health risks associated with shellfish consumption

  13. Quorum sensing regulates the osmotic stress response in Vibrio harveyi.

    Science.gov (United States)

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

    2015-01-01

    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

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

    Science.gov (United States)

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

    2016-04-01

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

  15. Identification and characterization of Vibrio cholerae surface proteins by radioiodination

    International Nuclear Information System (INIS)

    Whole cells and isolated outer membrane from Vibrio cholerae (Classical, Inaba) were radiolabeled with Iodogen or Iodo-beads as catalyst. Radiolabeling of whole cells was shown to be surface specific by sodium dodecyl sulfate-urea polyacrylamide gel electrophoresis of whole cells and cell fractions. Surface-labeled whole cells regularly showed 16 distinguishable protein species, of which nine were found in radiolabeled outer membrane preparations obtained by a lithium chloride- lithium acetate procedure. Eight of these proteins were found in outer membranes prepared by sucrose density gradient centrifugation and Triton X-100 extraction of radiolabeled whole cells. The mobility of several proteins was shown to be affected by temperature, and the major protein species exposed on the cell surface was shown to consist of at least two different peptides

  16. Inhibition of marine Vibrio sp. by pyoverdine from Pseudomonas aeruginosa PA1.

    Science.gov (United States)

    Zhang, Weiwei; Liang, Weikang; Li, Chenghua

    2016-01-25

    Siderophores are low-molecular-weight chemicals that are secreted by many microorganisms to chelate iron from the external environment in order to facilitate their growth and diverse metabolisms. In this study, a fluorescent siderophore, pyoverdine, secreted by Pseudomonas aeruginosa PA1 was purified by affinity chromatography using Cu-sepharose. Pyoverdine was determined to have a molecular mass of 1333.54 Da, as determined by MALDI-TOF/TOF, and belong to type I pyoverdine, as determined by PCR analysis of its corresponding outer membrane ferri-pyoverdine receptor. Pyoverdine showed different degrees of inhibitory effects on the growth of marine Vibrio sp. strains. It was also shown that the biofilm developed by Vibrio parahaemolyticus WzW1 and Wz2121 and Vibrio cyclitrophicus HS12 was significantly reduced, alone with the repressed growth in the presence of pyoverdine. Siderophore production was determined in the strains of Vibrio sp. in response to the pyoverdine-induced iron-limited conditions. The siderophore production of most Vibrio sp. was up-regulated, with the exception of the bacteria that produced little siderophore. Furthermore, Apostichopus japonicus cultured in pyoverdine pretreated seawater showed a relative percent of survival of 89% when they were challenged by Vibrio splendidus. Our results demonstrated that pyoverdine may be a promising agent that could be potentially applied to treat vibriosis. PMID:26476308

  17. Autoinducers Act as Biological Timers in Vibrio harveyi

    Science.gov (United States)

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

    2012-01-01

    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

  18. In-Vitro Antagonistic Characteristics of Crude Aqueous and Methanolic Extracts of Garcinia kola (Heckel) Seeds against Some Vibrio Bacteria

    OpenAIRE

    Okoh, Anthony I.; Dambudzo Penduka; Omobola O. Okoh

    2011-01-01

    The methanolic and aqueous extracts of Garcinia kola seeds were screened for their anti-Vibrio activities against 50 Vibrio isolates obtained from wastewater final effluents in the Eastern Cape Province, South Africa. The crude extracts at 10 mg/mL exhibited appreciable inhibitory activities against most of the test Vibrio isolates, with zones of inhibition ranging from 10–19 mm for methanol extract and 8–15 mm for the aqueous extracts. The minimum inhibitory concentrations (MIC) of the metha...

  19. Ecology, Inhibitory Activity, and Morphogenesis of a Marine Antagonistic Bacterium Belonging to the Roseobacter Clade

    DEFF Research Database (Denmark)

    Bruhn, Jesper Bartholin; Nielsen, Kristian Fog; Hjelm, Mette;

    2005-01-01

    Roseobacter strain 27-4 has been isolated from a turbot larval rearing unit and is capable of reducing mortality in turbot egg yolk sac larvae. Here, we demonstrate that the supernatant of Roseobacter 27-4 is lethal to the larval pathogens Vibrio anguillarum and Vibrio splendidus in a buffer syst...

  20. Interactions between pH, potassium, calcium, bromide, and phenol and their effects on the bioluminescence of Vibrio fischeri.

    Science.gov (United States)

    Berglind, Rune; Leffler, Per; Sjostrom, Michael

    2010-01-01

    Little attention has been paid to how the light produced by the bacterium Vibrio fischeri in the Microtox assay is dependent on the concentration of essential ions such as sodium and potassium, and whether the concentrations of these ions affect the sensitivity of the test system to toxic chemicals. Five selected factors, pH, potassium (K(+)), calcium (Ca(2+)), bromide (Br(-)), and phenol (Phe), were simultaneously varied over a set of systematically planned experiments according to a D-optimal design that supported the estimation of a model with linear, quadratic, and two-factor interatcions of the studied factors. The bacterial light production represented by the gamma values in the Microtox assay for the 24 selected combinations of factors was measured at 5 and 15 min. The gamma values varied from negative to positive values greater than 1, indicating stimulation and inhibition of bacterial light production, respectively. The relationship between the gamma values and the factor settings was investigated with multiple linear regression. After 5 min of exposure, the light production was significantly affected by linear and quadratic terms for K(+), pH, and Phe and an interaction between pH and Phe. The situation was more complex after 15 min of exposure, since in addition significant interactions were found for K x Phe and Ca x pH. The tolerance of V. fischeri to Phe was enhanced by increasing the K and Ca concentrations. Data indicate that the ion composition and pH of the sample, as well as the diluents, need to be considered when the toxicity of salts, water samples, and extracts of sediments and soils are tested using commercially certified toxicity test kits. PMID:20574912

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

    International Nuclear Information System (INIS)

    Highlights: • Fe accumulated in hepatopancreas tissues after iron-enriched exposure. • Ferritin expression was positively correlated with iron concentration in seawater. • Ferritin appears to be involved in iron homeostasis and immune defense mechanism of M. meretrix. • mRNAs of cytokine genes responded faster than antioxidant enzyme genes in immune defense mechanism. • The study gives a new potential biomarker for monitoring iron levels in seawater. - Abstract: The responses of genes encoding defense components such as ferritin, the lipopolysaccharide-induced tumor necrosis factor-alpha factor (LITAF), the inhibitor of nuclear factor-κB (IκB), 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 IκB at 3 h, ferritin at 24 h, and metallothionein and glutathione peroxidase at 48 h. 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

  2. Quorum sensing in Escherichia coli, Salmonella typhimurium, and Vibrio harveyi: A new family of genes responsible for autoinducer production

    Science.gov (United States)

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

    1999-01-01

    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 reporter strains capable of detecting only autoinducer 1 (AI-1) or autoinducer 2 (AI-2) have been constructed and used to show that many species of bacteria, including Escherichia coli MG1655, E. coli O157:H7, Salmonella typhimurium 14028, and S. typhimurium LT2 produce autoinducers similar or identical to the V. harveyi system 2 autoinducer AI-2. However, the domesticated laboratory strain E. coli DH5α does not produce this signal molecule. Here we report the identification and analysis of the gene responsible for AI-2 production in V. harveyi, S. typhimurium, and E. coli. The genes, which we have named luxSV.h., luxSS.t., and luxSE.c. respectively, are highly homologous to one another but not to any other identified gene. E. coli DH5α can be complemented to AI-2 production by the introduction of the luxS gene from V. harveyi or E. coli O157:H7. Analysis of the E. coli DH5α luxSE.c. gene shows that it contains a frameshift mutation resulting in premature truncation of the LuxSE.c. protein. Our results indicate that the luxS genes define a new family of autoinducer-production genes. PMID:9990077

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

    Science.gov (United States)

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

    2000-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Qing [State Key Laboratory of Stress Cell Biology, School of Life Science, Xiamen University, Xiamen 361102 (China); State Key Laboratory of Marine Environmental Science, School of Ocean and Earth Science, Xiamen University, Xiamen 361102 (China); Zhang, Yong [Department of Chemistry, College of Chemistry and Chemical Engineering, and the Key Laboratory of Chemical Biology of Fujian Province, Xiamen University, Xiamen 361102 (China); Peng, Hui-Fang [State Key Laboratory of Stress Cell Biology, School of Life Science, Xiamen University, Xiamen 361102 (China); Ke, Cai-Huan, E-mail: chke@xmu.edu.cn [State Key Laboratory of Marine Environmental Science, School of Ocean and Earth Science, Xiamen University, Xiamen 361102 (China); Huang, He-Qing, E-mail: hqhuang@xmu.edu.cn [State Key Laboratory of Stress Cell Biology, School of Life Science, Xiamen University, Xiamen 361102 (China); State Key Laboratory of Marine Environmental Science, School of Ocean and Earth Science, Xiamen University, Xiamen 361102 (China); Department of Chemistry, College of Chemistry and Chemical Engineering, and the Key Laboratory of Chemical Biology of Fujian Province, Xiamen University, Xiamen 361102 (China)

    2014-11-15

    Highlights: • Fe accumulated in hepatopancreas tissues after iron-enriched exposure. • Ferritin expression was positively correlated with iron concentration in seawater. • Ferritin appears to be involved in iron homeostasis and immune defense mechanism of M. meretrix. • mRNAs of cytokine genes responded faster than antioxidant enzyme genes in immune defense mechanism. • The study gives a new potential biomarker for monitoring iron levels in seawater. - Abstract: The responses of genes encoding defense components such as ferritin, the lipopolysaccharide-induced tumor necrosis factor-alpha factor (LITAF), the inhibitor of nuclear factor-κB (IκB), 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 IκB at 3 h, ferritin at 24 h, and metallothionein and glutathione peroxidase at 48 h. 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

  5. Virulence and molecular typing of Vibrio harveyi strains isolated from cultured dentex, gilthead sea bream and European sea bass.

    Science.gov (United States)

    Pujalte, M J; Sitjà-Bobadilla, A; Macián, M C; Belloch, C; Alvarez-Pellitero, P; Pérez-Sánchez, J; Uruburu, F; Garay, E

    2003-06-01

    Vibrio harveyi was isolated from internal organs or ulcers of diseased and apparently healthy gilthead sea bream (Sparus aurata) and European sea bass (Dicentrarchus labrax) cultured in several fish farms located on the Spanish Mediterranean coast. The prevalence of the bacterium was significantly higher in European sea bass than in gilthead sea bream, and was closely related to the season in both fish species, occurring almost exclusively on warm months (June to November). After phenotypic characterization, a selection of forty five isolates from gilthead sea bream, sea bass, and several isolates previously obtained from common dentex (Dentex dentex) of the same area, were molecularly typed by automated ribotyping and random amplified polymorphic DNA (RAPD) analysis. Cluster analysis of data established 8 RAPD types and 13 ribotypes among wild isolates, and the combination of both techniques allowed to define fourteen different groups and a clear discrimination of all outbreaks and samplings. Several strains isolated from diseased gilthead sea bream and sea bass and also from asymptomatic sea bream, were tested for virulence in both fish species by intracoelomic injection. All the isolates (11) were pathogenic for sea bass, with nine out of the eleven LD50 values ranging from 1.5 x 10(5) to 1.6 x 10(6) cfu/fish. Gilthead sea bream was unaffected by the seven tested strains, even by those more virulent for sea bass, and only one strain caused a 10% mortality at 4.2 x 10(7) cfu/fish. This is the first report on virulence of V. harveyi for sea bass. PMID:12866856

  6. Antibiotic and heavy-metal resistance of Vibrio parahaemolyticus isolated from fresh shrimps in Shanghai fish markets, China.

    Science.gov (United States)

    He, Yu; Jin, Lanlan; Sun, Fengjiao; Hu, Qiongxia; Chen, Lanming

    2016-08-01

    Vibrio parahaemolyticus is a causative agent of human serious seafood-borne gastroenteritis disease and even death. Shrimps, often eaten raw or undercooked, are an important reservoir of the bacterium. In this study, we isolated and characterized a total of 400 V. parahaemolyticus strains from commonly consumed fresh shrimps (Litopenaeus vannamei, Macrobrachium rosenbergii, Penaeus monodon, and Exopalaemon carinicauda) in Shanghai fish markets, China in 2013-2014. The results revealed an extremely low occurrence of pathogenic V. parahaemolyticus carrying two major toxic genes (tdh and trh, 0.0 and 0.5 %). However, high incidences of antibiotic resistance were observed among the strains against ampicillin (99 %), streptomycin (45.25 %), rifampicin (38.25 %), and spectinomycin (25.50 %). Approximately 24 % of the strains derived from the P. monodon sample displayed multidrug resistant (MDR) phenotypes, followed by 19, 12, and 6 % from the E. carinicauda, L. vannamei, and M. rosenbergii samples, respectively. Moreover, tolerance to heavy metals of Cr(3+) and Zn(2+) was observed in 90 antibiotic resistant strains, the majority of which also displayed resistance to Cu(2+) (93.3 %), Pb(2+) (87.8 %), and Cd(2+)(73.3 %). The pulsed-field gel electrophoresis (PFGE)-based genotyping of these strains revealed a total of 71 distinct pulsotypes, demonstrating a large degree of genomic variation among the isolates. The wide distribution of MDR and heavy-metal resistance isolates in the PFGE clusters suggested the co-existence of a number of resistant determinants in V. parahaemolyticus population in the detected samples. This study provided data in support of aquatic animal health management and food safety risk assessment in aquaculture industry. PMID:27083906

  7. Temporal and spatial distribution patterns of potentially pathogenic Vibrio spp. at recreational beaches of the German north sea.

    Science.gov (United States)

    Böer, Simone I; Heinemeyer, Ernst-August; Luden, Katrin; Erler, René; Gerdts, Gunnar; Janssen, Frank; Brennholt, Nicole

    2013-05-01

    The number of reported Vibrio-related wound infections associated with recreational bathing in Northern Europe has increased within the last decades. In order to study the health risk from potentially pathogenic Vibrio spp. in the central Wadden Sea, the seasonal and spatial distribution of Vibrio vulnificus, Vibrio parahaemolyticus, Vibrio alginolyticus and Vibrio cholerae were investigated at ten recreational beaches in this area over a 2-year period. V. alginolyticus and V. parahaemolyticus were found to be omnipresent all year round in the study area, while V. vulnificus occurrence was restricted to summer months in the estuaries of the rivers Ems and Weser. Multiple linear regression models revealed that water temperature is the most important determinant of Vibrio spp. occurrence in the area. Differentiated regression models showed a species-specific response to water temperature and revealed a particularly strong effect of even minor temperature increases on the probability of detecting V. vulnificus in summer. In sediments, Vibrio spp. concentrations were up to three orders of magnitude higher than in water. Also, V. alginolyticus and V. parahaemolyticus were found to be less susceptible towards winter temperatures in the benthic environment than in the water, indicating an important role of sediments for Vibrio ecology. While only a very small percentage of tested V. parahaemolyticus proved to be potentially pathogenic, the presence of V. vulnificus during the summer months should be regarded with care. PMID:23563708

  8. Relative contributions of Vibrio polysaccharide and quorum sensing to the resistance of Vibrio cholerae to predation by heterotrophic protists.

    Directory of Open Access Journals (Sweden)

    Shuyang Sun

    Full Text Available Protozoan grazing is a major mortality factor faced by bacteria in the environment. Vibrio cholerae, the causative agent of the disease cholera, is a natural inhabitant of aquatic ecosystems, and its survival depends on its ability to respond to stresses, such as predation by heterotrophic protists. Previous results show that grazing pressure induces biofilm formation and enhances a smooth to rugose morphotypic shift, due to increased expression of Vibrio polysaccharide (VPS. In addition to negatively controlling vps genes, the global quorum sensing (QS regulator, HapR, plays a role in grazing resistance as the ΔhapR strain is efficiently consumed while the wild type (WT is not. Here, the relative and combined contributions of VPS and QS to grazing resistance were investigated by exposing VPS and HapR mutants and double mutants in VPS and HapR encoding genes at different phases of biofilm development to amoeboid and flagellate grazers. Data show that the WT biofilms were grazing resistant, the VPS mutants were less resistant than the WT strain, but more resistant than the QS mutant strain, and that QS contributes to grazing resistance mainly in mature biofilms. In addition, grazing effects on biofilms of mixed WT and QS mutant strains were investigated. The competitive fitness of each strain in mixed biofilms was determined by CFU and microscopy. Data show that protozoa selectively grazed the QS mutant in mixed biofilms, resulting in changes in the composition of the mixed community. A small proportion of QS mutant cells which comprised 4% of the mixed biofilm biovolume were embedded in grazing resistant WT microcolonies and shielded from predation, indicating the existence of associational protection in mixed biofilms.

  9. Survey on antimicrobial resistance patterns in Vibrio vulnificus and Vibrio cholerae non-O1/non-O139 in Germany reveals carbapenemase-producing Vibrio cholerae in coastal waters.

    Science.gov (United States)

    Bier, Nadja; Schwartz, Keike; Guerra, Beatriz; Strauch, Eckhard

    2015-01-01

    An increase in the occurrence of potentially pathogenic Vibrio species is expected for waters in Northern Europe as a consequence of global warming. In this context, a higher incidence of Vibrio infections is predicted for the future and forecasts suggest that people visiting and living at the Baltic Sea are at particular risk. This study aimed to investigate antimicrobial resistance patterns among Vibrio vulnificus and Vibrio cholerae non-O1/non-O139 isolates that could pose a public health risk. Antimicrobial susceptibility of 141 V. vulnificus and 184 V. cholerae non-O1/non-O139 strains isolated from German coastal waters (Baltic Sea and North Sea) as well as from patients and retail seafood was assessed by broth microdilution and disk diffusion. Both species were susceptible to most of the agents tested (12 subclasses) and no multidrug-resistance was observed. Among V. vulnificus isolates, non-susceptibility was exclusively found toward aminoglycosides. In case of V. cholerae, a noticeable proportion of strains was non-susceptible to aminopenicillins and aminoglycosides. In addition, resistance toward carbapenems, quinolones, and folate pathway inhibitors was sporadically observed. Biochemical testing indicated the production of carbapenemases with unusual substrate specificity in four environmental V. cholerae strains. Most antimicrobial agents recommended for treatment of V. vulnificus and V. cholerae non-O1/non-O139 infections were found to be effective in vitro. However, the occurrence of putative carbapenemase producing V. cholerae in German coastal waters is of concern and highlights the need for systematic monitoring of antimicrobial susceptibility in potentially pathogenic Vibrio spp. in Europe. PMID:26579088

  10. Survey on antimicrobial resistance patterns in Vibrio vulnificus and Vibrio cholerae non-O1/non-O139 in Germany reveals carbapenemase-producing Vibrio cholerae in coastal waters

    Directory of Open Access Journals (Sweden)

    Nadja eBier

    2015-10-01

    Full Text Available An increase in the occurrence of potentially pathogenic Vibrio species is expected for waters in Northern Europe as a consequence of global warming. In this context, a higher incidence of Vibrio infections is predicted for the future and forecasts suggest that people visiting and living at the Baltic Sea are at particular risk.This study aimed to investigate antimicrobial resistance patterns among Vibrio vulnificus and Vibrio cholerae non-O1/non-O139 isolates that could pose a public health risk. Antimicrobial susceptibility of 141 V. vulnificus and 184 V. cholerae non-O1/non-O139 strains isolated from German coastal waters (Baltic Sea and North Sea as well as from patients and retail seafood was assessed by broth microdilution and disk diffusion. Both species were susceptible to most of the agents tested (12 subclasses and no multidrug-resistance was observed. Among V. vulnificus isolates, non-susceptibility was exclusively found towards aminoglycosides. In case of V. cholerae, a noticeable proportion of strains was non-susceptible to aminopenicillins and aminoglycosides. In addition, resistance towards carbapenems, quinolones, and folate pathway inhibitors was sporadically observed. Biochemical testing indicated the production of carbapenemases with unusual substrate specificity in four environmental V. cholerae strains. Most antimicrobial agents recommended for treatment of V. vulnificus and V. cholerae non-O1/non-O139 infections were found to be effective in vitro. However, the occurrence of putative carbapenemase producing V. cholerae in German coastal waters is of concern and highlights the need for systematic monitoring of antimicrobial susceptibility in potentially pathogenic Vibrio spp. in Europe.

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

    DEFF Research Database (Denmark)

    Valles, Iliana Espinoza; Vora, Gary J; Lin, Baochuan;

    2015-01-01

    Vibrio harveyi CAIM 1792 is a marine bacterial strain that causes mortality in farmed shrimp in north-west Mexico, and the identification of virulence genes in this strain is important for understanding its pathogenicity. The aim of this work was to compare the V. harveyi CAIM 1792 genome...

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

    Science.gov (United States)

    Espinoza-Valles, Iliana; Vora, Gary J; Lin, Baochuan; Leekitcharoenphon, Pimlapas; González-Castillo, Adrián; Ussery, Dave; Høj, Lone; Gomez-Gil, Bruno

    2015-09-01

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

  13. Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment and cultured oysters in the Chesapeake Bay, Maryland, USA

    Directory of Open Access Journals (Sweden)

    KristiSShaw

    2014-05-01

    Full Text Available To determine if a storm event (i.e., high winds, large volumes of precipitation could alter concentrations of Vibrio vulnificus and Vibrio parahaemolyticus in aquacultured oysters (Crassostrea virginica and associated surface water and sediment, this study followed a sampling timeline before and after Hurricane Irene impacted the Chesapeake Bay estuary in late August 2011. Aquacultured oysters were sampled from two levels in the water column: surface 0.3 m and near-bottom just above the sediment. Concentrations of each Vibrio spp. and associated virulence genes were measured in oysters with a combination of real-time PCR and most probable number enrichment methods, and in sediment and surface water with real-time PCR. While concentration shifts of each Vibrio species were apparent post-storm, statistical tests indicated no significant change in concentration change for either Vibrio species by location (surface or near bottom oysters or date sampled (oyster tissue, surface water and sediment concentrations. V. vulnificus in oyster tissue was correlated with total suspended solids (r=0.41, p=0.04, and V. vulnificus in sediment was correlated with secchi depth (r=-0.93, p< 0.01, salinity (r=-0.46, p=0.02, tidal height (r=-0.45, p=0.03, and surface water V. vulnificus (r=0.98, p< 0.01. V. parahaemolyticus in oyster tissue did not correlate with environmental measurements, but V. parahaemolyticus in sediment and surface water correlated with several measurements including secchi depth (r=-0.48, p=0.02[sediment]; r=-0.97 p< 0.01[surface water] and tidal height (r=-0.96. p< 0.01[sediment], r=-0.59,p< 0.01 [surface water]. The concentrations of Vibrio spp. were higher in oysters relative to other studies (average V. vulnificus 4x105 MPN g-1, V. parahaemolyticus 1x105 MPN g-1, and virulence-associated genes were detected in most oyster samples. This study provides a first estimate of storm-related Vibrio density changes in oyster tissues, sediment and

  14. Comparative genomic analysis of Vibrio parahaemolyticus: serotype conversion and virulence

    Directory of Open Access Journals (Sweden)

    Gil Ana I

    2011-06-01

    Full Text Available Abstract Background Vibrio parahaemolyticus is a common cause of foodborne disease. Beginning in 1996, a more virulent strain having serotype O3:K6 caused major outbreaks in India and other parts of the world, resulting in the emergence of a pandemic. Other serovariants of this strain emerged during its dissemination and together with the original O3:K6 were termed strains of the pandemic clone. Two genomes, one of this virulent strain and one pre-pandemic strain have been sequenced. We sequenced four additional genomes of V. parahaemolyticus in this study that were isolated from different geographical regions and time points. Comparative genomic analyses of six strains of V. parahaemolyticus isolated from Asia and Peru were performed in order to advance knowledge concerning the evolution of V. parahaemolyticus; specifically, the genetic changes contributing to serotype conversion and virulence. Two pre-pandemic strains and three pandemic strains, isolated from different geographical regions, were serotype O3:K6 and either toxin profiles (tdh+, trh- or (tdh-, trh+. The sixth pandemic strain sequenced in this study was serotype O4:K68. Results Genomic analyses revealed that the trh+ and tdh+ strains had different types of pathogenicity islands and mobile elements as well as major structural differences between the tdh pathogenicity islands of the pre-pandemic and pandemic strains. In addition, the results of single nucleotide polymorphism (SNP analysis showed that 94% of the SNPs between O3:K6 and O4:K68 pandemic isolates were within a 141 kb region surrounding the O- and K-antigen-encoding gene clusters. The "core" genes of V. parahaemolyticus were also compared to those of V. cholerae and V. vulnificus, in order to delineate differences between these three pathogenic species. Approximately one-half (49-59% of each species' core genes were conserved in all three species, and 14-24% of the core genes were species-specific and in different

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

    OpenAIRE

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

    2015-01-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

  17. Extreme Ionizing-Radiation-Resistant Bacterium

    Science.gov (United States)

    Vaishampayan, Parag A.; Venkateswaran, Kasthuri J.; Schwendner, Petra

    2013-01-01

    potential for transfer, and subsequent proliferation, on another solar body such as Mars and Europa. These organisms are more likely to escape planetary protection assays, which only take into account presence of spores. Hence, presences of extreme radiation-resistant Deinococcus in the cleanroom facility where spacecraft are assembled pose a serious risk for integrity of life-detection missions. The microorganism described herein was isolated from the surfaces of the cleanroom facility in which the Phoenix Lander was assembled. The isolated bacterial strain was subjected to a comprehensive polyphasic analysis to characterize its taxonomic position. This bacterium exhibits very low 16SrRNA similarity with any other environmental isolate reported to date. Both phenotypic and phylogenetic analyses clearly indicate that this isolate belongs to the genus Deinococcus and represents a novel species. The name Deinococcus phoenicis was proposed after the Phoenix spacecraft, which was undergoing assembly, testing, and launch operations in the spacecraft assembly facility at the time of isolation. D. phoenicis cells exhibited higher resistance to ionizing radiation (cobalt-60; 14 kGy) than the cells of the D. radiodurans (5 kGy). Thus, it is in the best interest of NASA to thoroughly characterize this organism, which will further assess in determining the potential for forward contamination. Upon the completion of genetic and physiological characteristics of D. phoenicis, it will be added to a planetary protection database to be able to further model and predict the probability of forward contamination.

  18. A dual-color flow cytometry protocol for the simultaneous detection of Vibrio parahaemolyticus and Salmonella typhimurium using aptamer conjugated quantum dots as labels

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Nuo; Wu, Shijia [State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122 (China); Yu, Ye [Zhangjiagang Entry-Exit Inspection and Quarantine Bureau, Zhangjiangang 215600 (China); Ma, Xiaoyuan; Xia, Yu; Chen, Xiujuan; Huang, Yukun [State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122 (China); Wang, Zhouping, E-mail: wangzp@jiangnan.edu.cn [State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122 (China)

    2013-12-04

    Graphical abstract: -- Highlights: •Two bacteria were simultaneously detected using QD-apt as labels by flow cytometry. •QD-apt were used for recognition and fluorescence detection of two bacteria. •The method was applied successfully for bacteria detection in real samples. -- Abstract: A sensitive, specific method for the collection and detection of pathogenic bacteria was demonstrated using quantum dots (QDs) as a fluorescence marker coupled with aptamers as the molecular recognition element by flow cytometry. The aptamer sequences were selected using a bacterium-based SELEX strategy in our laboratory for Vibrio parahaemolyticus and Salmonella typhimurium that, when applied in this method, allows for the specific recognition of the bacteria from complex mixtures including shrimp samples. Aptamer-modified QDs (QD-apt) were employed to selectively capture and simultaneously detect the target bacteria with high sensitivity using the fluorescence of the labeled QDs. The signal intensity is amplified due to the high photostability of QDs nanoparticles, resulting in improved sensitivity over methods using individual dye-labeled probes. This proposed method is promising for the sensitive detection of other pathogenic bacteria in food stuff if suitable aptamers are chosen. The method may also provide another potential platform for the application of aptamer-conjugated QDs in flow cytometry.

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

    Science.gov (United States)

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

    2011-06-15

    A bioassay using the luminescent bacterium Vibrio-qinghaiensis sp.-Q67 associated with solid-phase extraction (SPE) was developed for evaluating the variation of ecotoxicity along with the reduction of organic substances in a domestic wastewater treatment plant employing an oxidation ditch process. With effective elimination of the interference from all inorganic substances by the SPE operation, the ecotoxicity of the water, as expressed by the toxicity impact index, TII(50) (%) after a model-based regression and parameter transformation, was found to decrease from 50.51% in the influent to 25.84% after the grid chamber and then to 1.38% for the secondary effluent, but the final chlorination stage resulted in a slight TII(50) increase. Of the two typical tertiary treatment processes, coagulation could not assist further reduction of the ecotoxicity while carbon adsorption could reduce the TII(50) to as low as 0.96%. When enhanced primary treatment was conducted, the influent TII(50) could be directly reduced to 7.36%. A good correlative relationship was found between the total COD concentration and the TII(50) value at different stages of the wastewater treatment process. PMID:21440989

  20. Biochemical characterization of NfsA, the Escherichia coli major nitroreductase exhibiting a high amino acid sequence homology to Frp, a Vibrio harveyi flavin oxidoreductase.

    Science.gov (United States)

    Zenno, S; Koike, H; Kumar, A N; Jayaraman, R; Tanokura, M; Saigo, K

    1996-01-01

    We identified the nfsA gene, encoding the major oxygen-insensitive nitroreductase in Escherichia coli, and determined its position on the E. coli map to be 19 min. We also purified its gene product, NfsA, to homogeneity. It was suggested that NfsA is a nonglobular protein with a molecular weight of 26,799 and is associated tightly with a flavin mononucleotide. Its amino acid sequence is highly similar to that of Frp, a flavin oxidoreductase from Vibrio harveyi (B. Lei, M. Liu, S. Huang, and S.-C. Tu, J. Bacteriol. 176:3552-3558, 1994), an observation supporting the notion that E. coli nitroreductase and luminescent-bacterium flavin reductase families are intimately related in evolution. Although no appreciable sequence similarity was detected between two E. coli nitroreductases, NfsA and NfsB, NfsA exhibited a low level of the flavin reductase activity and a broad electron acceptor specificity similar to those of NfsB. NfsA reduced nitrofurazone by a ping-pong Bi-Bi mechanism possibly to generate a two-electron transfer product. PMID:8755878

  1. Crystallization and preliminary X-ray crystallographic studies of VibE, a vibriobactin-specific 2,3-dihydroxybenzoate-AMP ligase from Vibrio cholerae

    International Nuclear Information System (INIS)

    This article reports the molecular cloning, protein expression and purification, crystallization and preliminary X-ray crystallographic analysis of the vibriobactin synthetase VibE from V. cholerae. Vibriobactin synthetases (VibABCDEFH) catalyze the biosynthesis of vibriobactin in the pathogenic bacterium Vibrio cholerae. VibE, a vibriobactin-specific 2,3-dihydroxybenzoate-AMP ligase, plays a critical role in the transfer of 2,3-dihydroxybenzoate to the aryl carrier protein domain of holo VibB. Here, the cloning, protein expression and purification, crystallization and preliminary X-ray crystallographic analysis of VibE from V. cholerae are reported. The VibE crystal diffracted to 2.3 Å resolution. The crystal belonged to space group P21, with unit-cell parameters a = 56.471, b = 45.927, c = 77.014 Å, β = 95.895°. There is one protein molecule in the asymmetric unit, with a corresponding Matthews coefficient of 1.63 Å3 Da−1 and solvent content of 24.41%

  2. Cloning, expression, purification, crystallization and preliminary X-ray analysis of the 31 kDa Vibrio cholerae heat-shock protein VcHsp31

    International Nuclear Information System (INIS)

    A heat-shock protein from V. cholerae (VcHsp31) has been cloned, expressed, purified and crystallized. Crystals of VcHsp31 belonged to a monoclinic space group and diffracted to 1.9 Å resolution. The Gram-negative bacterium Vibrio cholerae, which is responsible for the diarrhoeal disease cholera in humans, induces the expression of numerous heat-shock genes. VcHsp31 is a 31 kDa putative heat-shock protein that belongs to the DJ-1/PfpI superfamily, functioning as both a chaperone and a protease. VcHsp31 has been cloned, overexpressed and purified by Ni2+–NTA affinity chromatography followed by gel filtration. Crystals of VcHsp31 were grown in the presence of PEG 6000 and MPD; they belonged to space group P21 and diffracted to 1.9 Å resolution. Assuming the presence of six molecules in the asymmetric unit, the Matthews coefficient was estimated to be 1.97 Å3 Da−1, corresponding to a solvent content of 37.4%

  3. Evaluation of RAPD-PCR and protein profile analysis to differentiate Vibrio harveyi strains prevalent along the southwest coast of India

    Indian Academy of Sciences (India)

    Biswajit Maiti; Malathi Shekar; Rekha Khushiramani; Iddya Karunasagar; Indrani Karunasagar

    2009-12-01

    Sixty five isolates of Vibrio harveyi were subjected to random amplified polymorphic DNA (RAPD)-PCR analysis and protein profiling to investigate the genetic variability among V. harveyi prevalent along the coast and also assess the discriminating ability of these two molecular methods. A total of 10 RAPD primers were assayed for their specificity in detecting V. harveyi, of which only two primers: PM3 and CRA25 were highly reproducible and found suitable for use in RAPD-PCR. The genetic diversity among V. harveyi isolates assessed by RAPD-PCR using PM3 primer yielded 35 different RAPD patterns which clustered the isolates into 15 groups at 72% similarity level. Similarly, RAPD-PCR with CRA25 clustered the 38 patterns into 10 groups at 74% similarity. The discriminatory index $(D)$ value calculated for RAPD fingerprints generated with PM3 and CRA25 were 0.90 and 0.85, respectively. On the other hand, molecular typing of V. harveyi using whole cell proteins generated profiles that showed no major difference indicating the technique to be not useful in typing strains of this bacterium. However, a few of the isolates showed the presence of unique band of 28 kDa that needs to be further investigated to understand the role of the protein in disease process if any.

  4. A dual-color flow cytometry protocol for the simultaneous detection of Vibrio parahaemolyticus and Salmonella typhimurium using aptamer conjugated quantum dots as labels

    International Nuclear Information System (INIS)

    Graphical abstract: -- Highlights: •Two bacteria were simultaneously detected using QD-apt as labels by flow cytometry. •QD-apt were used for recognition and fluorescence detection of two bacteria. •The method was applied successfully for bacteria detection in real samples. -- Abstract: A sensitive, specific method for the collection and detection of pathogenic bacteria was demonstrated using quantum dots (QDs) as a fluorescence marker coupled with aptamers as the molecular recognition element by flow cytometry. The aptamer sequences were selected using a bacterium-based SELEX strategy in our laboratory for Vibrio parahaemolyticus and Salmonella typhimurium that, when applied in this method, allows for the specific recognition of the bacteria from complex mixtures including shrimp samples. Aptamer-modified QDs (QD-apt) were employed to selectively capture and simultaneously detect the target bacteria with high sensitivity using the fluorescence of the labeled QDs. The signal intensity is amplified due to the high photostability of QDs nanoparticles, resulting in improved sensitivity over methods using individual dye-labeled probes. This proposed method is promising for the sensitive detection of other pathogenic bacteria in food stuff if suitable aptamers are chosen. The method may also provide another potential platform for the application of aptamer-conjugated QDs in flow cytometry

  5. Essential oils of Nigella sativa protects Artemia from the pathogenic effect of Vibrio parahaemolyticus Dahv2.

    Science.gov (United States)

    Manju, Sivalingam; Malaikozhundan, Balasubramanian; Withyachumnarnkul, Boonsirm; Vaseeharan, Baskaralingam

    2016-05-01

    The anti-Vibrio activity of essential oils (EOs) of nine medicinal plants was tested against 28 Vibrio spp. isolated from diseased Fenneropenaeus indicus. EO of Nigella sativa exhibited anti-Vibrio activity against all Vibrio spp. and greater inhibition was noted for the isolate V2 which was identified as Vibrio parahaemolyticus Dahv2. Further, EO of N. sativa effectively inhibited V. parahaemolyticus Dahv2 with an inhibition zone of 23.9mm at 101.2μgml(-1). Moreover, EO of N. sativa revealed anti-biofilm activity at 101.2μgml(-1) against V. parahaemolyticus Dahv2 and inhibited the growth of V. parahaemolyticus Dahv2 at 100μgml(-1).In vivo experimental infection studies showed that the survival of Artemia spp. infected with V. parahaemolyticus Dahv2 at 1×10(3)cfuml(-1) was only 40%. However, the survival of Artemia spp. was significantly increased after challenge with 100μgml(-1) of EO of N. sativa. EO of N. sativa showed higher anti-oxidant potential and total phenol content than other EOs tested. The anti-oxidant activity of EO of N. sativa was highly correlated to their total phenolic contents (r=0.836, P<0.05). This observation suggests that EO of N. sativa protected the Artemia spp. after experimental infection of V. parahaemolyticus Dahv2. PMID:26945773

  6. Coral-mucus-associated Vibrio integrons in the Great Barrier Reef: genomic hotspots for environmental adaptation.

    Science.gov (United States)

    Koenig, Jeremy E; Bourne, David G; Curtis, Bruce; Dlutek, Marlena; Stokes, H W; Doolittle, W Ford; Boucher, Yan

    2011-06-01

    Integron cassette arrays in a dozen cultivars of the most prevalent group of Vibrio isolates obtained from mucus expelled by a scleractinian coral (Pocillopora damicornis) colony living on the Great Barrier Reef were sequenced and compared. Although all cultivars showed >99% identity across recA, pyrH and rpoB genes, no two had more than 10% of their integron-associated gene cassettes in common, and some individuals shared cassettes exclusively with distantly-related members of the genus. Of cassettes shared within the population, a number appear to have been transferred between Vibrio isolates, as assessed by phylogenetic analysis. Prominent among the mucus Vibrio cassettes with potentially inferable functions are acetyltransferases, some with close similarity to known antibiotic-resistance determinants. A subset of these potential resistance cassettes were shared exclusively between the mucus Vibrio cultivars, Vibrio coral pathogens and human pathogens, thus illustrating a direct link between these microbial niches through exchange of integron-associated gene cassettes. PMID:21270840

  7. Occurrence of Vibrio and Salmonella species in mussels (Mytilus galloprovincialis) collected along the Moroccan Atlantic coast.

    Science.gov (United States)

    Mannas, Hasna; Mimouni, Rachida; Chaouqy, Noureddine; Hamadi, Fatima; Martinez-Urtaza, Jaime

    2014-01-01

    This study reports the occurrence of different Vibrio and Salmonella species in 52 samples of Mytilus galloprovincialis collected from four sites along the Atlantic coast between Agadir and Essaouira (Anza, Cap Ghir, Imssouane and Essaouira). The level of Escherichia coli (E. coli) was also determined to evaluate the degree of microbial pollution in the investigated areas. In this study three methods were used : AFNOR NF EN ISO 6579 V08-013 for Salmonella spp., the provisional method routinely used by several laboratories (Institut Pasteur, Paris,…) for Vibrio cholerae and Vibrio parahaemolyticus in the seafood, and the most probable number method (MPN) using Norm ISO/TS 16649-3 (2005) for E. coli. The most frequently isolated Vibrios were Vibrio alginolyticus (90.4% of samples), followed by V. cholerae non O1 non O139 (15.4%) and V. parahaemolyticus (7.7%). Salmonella spp. was found in 15% of the samples. The number of E. coli ranged between 0.2/100 g and 1.8 10(3) /100 g of mussel soft tissues. This study indicates the potential sanitary risk associated with the presence of pathogenic bacteria in cultivated mussels in the two populous regions of southern Morocco, where shellfish production and maritime tourism are important to the local economy. PMID:24936389

  8. Evaluation of a rapid polymerase chain reaction based identification technique for Vibrio cholerae isolates.

    Science.gov (United States)

    le Roux, W J; Masoabi, D; de Wet, C M E; Venter, S N

    2004-01-01

    Rapid and accurate identification of waterborne pathogens, such as Vibrio cholerae, in drinking-water sources is important to enable effective resource management and public health protection. Phenotypic systems currently being used for the identification of Vibrio cholerae isolates are time-consuming and the need exists for the development of suitable molecular techniques that can offer both fast and reliable identification. During this study, isolates identified as Vibrio cholerae by means of two different biochemical test systems (API 20E and VITEK 32) were analysed with the polymerase chain reaction (PCR) to compare the reliability of the various identification systems. The selected PCR technique amplified a sequence within the outer membrane protein of Vibrio cholerae, a gene specific for V. cholerae. It was found that out of 243 isolates biochemically identified as V. cholerae with either the API or VITEK system, 21 isolates did not give a positive result with the PCR detection method. Sequencing the 16S rDNA of more than half of these isolates and comparison of the sequences with Internet databases indicated that most of the isolates belonged to the genus Aeromonas. The results indicated that the rapid PCR procedure was more accurate than the API or VITEK systems currently being used for the phenotypic identification of Vibrio cholerae isolates. PMID:15318514

  9. POTENCY OF VIBRIO ISOLATES FOR BIOCONTROL OF VIBRIOSIS IN TIGER SHRIMP (PENAEUS MONODON LARVAE

    Directory of Open Access Journals (Sweden)

    B. W. LAY

    2003-01-01

    Full Text Available This study was carried out to obtain Vibrio isolates able to function as biocontr ol of vibriosis in shrimp hatchery. Thirty one Vibrio isolates were isolated from tiger shrimp larvae and hatchery environments, i.e. Labuan, Pangandaran, and Lampung, Indonesia. Pathogenic V. harveyi MR5339 was obtained from Maros, South-Sulawesi and was made as a rifampicin resistant mutant (RFR to screen for those 31 Vibrio isolates in in vitro assays and to allow us to monitor their presence in shrimp larvae and larval rearing water. Almost all Vibrio isolates could inhibit the growth of pathogenic V. harveyi MR5339 RFR. SKT-b isolate from Skeletonema was the most effective to inhibit the growth of V. harveyi MR5339 Rf* and significantly reduced larval mortality in pathogen challenge assays. These prospective biocontrol bacteria, at concentration of 10" CFU/ml, did not show pathogenicity to shrimp larvae. SKT-b was Gram negative, short rod-shape, exhibited yellow colonies on TCBS and swarming on SWC-agar media, motile, u tilized glucose and sucrose but not lactose: produced extra-cellular protease and amylase, but did not produce chitmase. Partial sequencing of 16S-rRNA gene SKT-b showed SKT-b similarity to Vibrio alginofyticus.

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

    Science.gov (United States)

    Busico-Salcedo, Nancy; Owens, Leigh

    2013-09-01

    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

  11. Molybdate Reduction to Molybdenum Blue by an Antarctic Bacterium

    OpenAIRE

    S. A. Ahmad; Shukor, M. Y.; Shamaan, N. A.; W. P. Mac Cormack; Syed, M. A.

    2013-01-01

    A molybdenum-reducing bacterium from Antarctica has been isolated. The bacterium converts sodium molybdate or Mo6+ to molybdenum blue (Mo-blue). Electron donors such as glucose, sucrose, fructose, and lactose supported molybdate reduction. Ammonium sulphate was the best nitrogen source for molybdate reduction. Optimal conditions for molybdate reduction were between 30 and 50 mM molybdate, between 15 and 20°C, and initial pH between 6.5 and 7.5. The Mo-blue produced had a unique absorption spe...

  12. Spiral conformation of Vibrio cholerae as determined by scanning electron microscopy of elongated cells induced by cephalexin treatment.

    OpenAIRE

    Konishi, H.; Katayama, A.; Ito, T.; Tanaka, S.; Yoshii, Z

    1986-01-01

    The elongated cells of Vibrio spp. induced by cephalexin treatment were examined by scanning electron microscopy. The results showed that Vibrio cholerae has a twisted cell body and a right-handed spiral conformation and that the cell bodies of V. parahaemolyticus and V. alginolyticus are straight rather than curved.

  13. Draft Genome Sequence of Environmental Vibrio cholerae 2012EL-1759 with Similarities to the V. cholerae O1 Classical Biotype

    OpenAIRE

    Katz, Lee S.; Turnsek, Maryann; Kahler, Amy; Hill, Vincent R.; Boyd, E. Fidelma; Tarr, Cheryl L.

    2014-01-01

    Vibrio cholerae 2012EL-1759 is an environmental isolate from Haiti that was recovered in 2012 during a cholera outbreak. The genomic backbone is similar to that of the prototypical V. cholerae O1 classical biotype strain O395, and it carries the Vibrio pathogenicity islands (VPI-1 and VPI-2) and a cholera toxin (CTX) prephage.

  14. The repertoire of glycosphingolipids recognized by Vibrio cholerae.

    Directory of Open Access Journals (Sweden)

    John Benktander

    Full Text Available The binding of cholera toxin to the ganglioside GM1 as the initial step in the process leading to diarrhea is nowadays textbook knowledge. In contrast, the knowledge about the mechanisms for attachment of Vibrio cholerae bacterial cells to the intestinal epithelium is limited. In order to clarify this issue, a large number of glycosphingolipid mixtures were screened for binding of El Tor V. cholerae. Several specific interactions with minor complex non-acid glycosphingolipids were thereby detected. After isolation of binding-active glycosphingolipids, characterization by mass spectrometry and proton NMR, and comparative binding studies, three distinct glycosphingolipid binding patterns were defined. Firstly, V. cholerae bound to complex lacto/neolacto glycosphingolipids with the GlcNAcβ3Galβ4GlcNAc sequence as the minimal binding epitope. Secondly, glycosphingolipids with a terminal Galα3Galα3Gal moiety were recognized, and the third specificity was the binding to lactosylceramide and related compounds. V. cholerae binding to lacto/neolacto glycosphingolipids, and to the other classes of binding-active compounds, remained after deletion of the chitin binding protein GbpA. Thus, the binding of V. cholerae to chitin and to lacto/neolacto containing glycosphingolipids represents two separate binding specificities.

  15. [The in vitro action of plants on Vibrio cholerae].

    Science.gov (United States)

    Guevara, J M; Chumpitaz, J; Valencia, E

    1994-01-01

    Natural products of several plants, according to the geographic location, are used by Peruvian people in the popular treatment of diarrhea, with good success. When cholerae cases appeared in Peru, we were interested to know the "in vitro" effect against Vibrio cholerae 01, of these useful plants to treat diarrhea. The following plants were tested: Cichorium intybus, Althaea officinalis, Psorela glandulosa, Geranium maculatum, Punica granatum, Malus sativa, Cydonia oblonga, Chenopodium ambrosoides, Krameria triandria, Tea chinensis, Daucus carota, Persea gratissima, Psidium guayaba and Lippia dulcis. Decoction or infusion of the plants were used in the "in vitro" experiments. The following plants showed no "in vitro" effect against V. cholerae: Cichorium intybus, Althaea officinalis, Psorela glandulosa, Geranium maculatum, Chenopodium ambrosoides, Krameria triandria, Psidium guayaba, Lippia dulcis and Daucus carota. Decoction of Malus sativa and Cydenia oblonga showed bactericidal effect for their acidity and stone avocado (Persea gratissima) a late bactericidal effect. Tea infusión and the decoction of Punica granatum peel, showed the best bactericidal effect and we suggest to use them as to stop cholera spreading. PMID:8018898

  16. Antigenicity analysis of Vibrio harveyi TS-628 strain

    Institute of Scientific and Technical Information of China (English)

    QIN Yingxue; WANG Jun; WANG Shifeng; YAN Qingpi

    2007-01-01

    Vibrio harveyi,the major causative agent of vibriosis,affects a diverse range of marine cultured organisms over a wide geographical area.However,reports about screening the effective antigen and research on vaccines of V.harveyi are scarce.Flagellin,lipopolysaccharide (LPS) and outer membrane proteins (OMP) are major immunogenic antigens in many Gram-negative bacteria.In this study,the flagellin,OMP and LPS of the V.harveyi TS-628 strain isolated from infected groupers were extracted and Western blot analysis was used to detect the antigenicity of these extractions.Results of the Western blot assay reveal that there are four positive flagellin bands:35 kDa,38 kDa,43 kDa,and 52 kDa,of which the 43 kDa and 52 kDa bands displayed the strongest positive reaction.There are five positive OMP bands about 35 kDa,38 kDa,43 kDa,47 kDa,and 52 kDa,of which the 43 kDa appeared to have the strongest positive reaction although the other four proteins also displayed strong reactions.However,LPS is Western blot-negative.These results indicate that the 43 kDa and 52 kDa flagellin and OMP of size 43 kDa,52 kDa can be candidates for developing vaccines against V.harveyi.

  17. Starvation effects on pathogenic Vibrio alginolyticus in natural seawater

    Institute of Scientific and Technical Information of China (English)

    YI Jiabo; CHEN Qiang; ZOU Wenzheng; YAN Qingpi; ZHUANG Zhixia; WANG Xiaoru

    2008-01-01

    To get a better understanding of the starvation survival strategy of pathogenic Vibrio alginolyticus,log-phase cells were inoculated into sterile natural seawater for starvation studies.The results showed that all of total bacteria number,viable bacteria number and CFU number of V. alginolyticus increased remarkably at the initial starvation stage;after reaching their peaks at 5 d,both total bacteria number and viable bacteria number of V. alginolyricus fell slowly,while the CFU number fell more quickly after reaching its peak at 10 d;V.alginolyticus elongated their cells at the porphase of starvation,and then shrunk their volume and turned their shapes into ovals from rods at the anaphase of starvation;starved cells showed more sensitivity to heating and UV;starved cells showed n0 significant difference from unstarved ones at the lowest detection limit determined by indirect enzyme-linked immu-nosorbent assay(ELISA);starred cells'ability to adhere to the skin mucus of large yellow croaker(Pseudosciaena crocea)shorwed a sharp decline as the starvation time increases;the cellular protein of V.alginotyticus increased remarkably at the ana-phase of starvation.The results indicated that pathogenic V. alginolyticus could survive in starvation for relatively long periods of time(≥2 months)in 28℃ natural seawater due to the morphological and physiological changes;however,starved V. alginolytic-us cells showed Iess virulence and higher sensitivity under environmental stresses.

  18. Structural and Thermodynamic Characterization of Vibrio fischeri CcdB*

    Science.gov (United States)

    De Jonge, Natalie; Hohlweg, Walter; Garcia-Pino, Abel; Respondek, Michal; Buts, Lieven; Haesaerts, Sarah; Lah, Jurij; Zangger, Klaus; Loris, Remy

    2010-01-01

    CcdBVfi from Vibrio fischeri is a member of the CcdB family of toxins that poison covalent gyrase-DNA complexes. In solution CcdBVfi is a dimer that unfolds to the corresponding monomeric components in a two-state fashion. In the unfolded state, the monomer retains a partial secondary structure. This observation correlates well with the crystal and NMR structures of the protein, which show a dimer with a hydrophobic core crossing the dimer interface. In contrast to its F plasmid homologue, CcdBVfi possesses a rigid dimer interface, and the apparent relative rotations of the two subunits are due to structural plasticity of the monomer. CcdBVfi shows a number of non-conservative substitutions compared with the F plasmid protein in both the CcdA and the gyrase binding sites. Although variation in the CcdA interaction site likely determines toxin-antitoxin specificity, substitutions in the gyrase-interacting region may have more profound functional implications. PMID:19959472

  19. Structural and thermodynamic characterization of Vibrio fischeri CcdB.

    Science.gov (United States)

    De Jonge, Natalie; Hohlweg, Walter; Garcia-Pino, Abel; Respondek, Michal; Buts, Lieven; Haesaerts, Sarah; Lah, Jurij; Zangger, Klaus; Loris, Remy

    2010-02-19

    CcdB(Vfi) from Vibrio fischeri is a member of the CcdB family of toxins that poison covalent gyrase-DNA complexes. In solution CcdB(Vfi) is a dimer that unfolds to the corresponding monomeric components in a two-state fashion. In the unfolded state, the monomer retains a partial secondary structure. This observation correlates well with the crystal and NMR structures of the protein, which show a dimer with a hydrophobic core crossing the dimer interface. In contrast to its F plasmid homologue, CcdB(Vfi) possesses a rigid dimer interface, and the apparent relative rotations of the two subunits are due to structural plasticity of the monomer. CcdB(Vfi) shows a number of non-conservative substitutions compared with the F plasmid protein in both the CcdA and the gyrase binding sites. Although variation in the CcdA interaction site likely determines toxin-antitoxin specificity, substitutions in the gyrase-interacting region may have more profound functional implications. PMID:19959472

  20. Antibiotic resistance of Vibrio harveyi isolated from seawater in Korea.

    Science.gov (United States)

    Kang, Chang-Ho; Kim, YongGyeong; Oh, Soo Ji; Mok, Jong-Soo; Cho, Myung-Hwan; So, Jae-Seong

    2014-09-15

    Vibrio harveyi is an opportunistic human pathogen that may cause gastroenteritis, severe necrotizing soft-tissue infections, and primary septicemia, with a potentially high rate of lethality. In this study, we isolated and characterized V. harveyi from seawater collected from the West Sea in Korea, including sites located near shellfish farms. For the initial isolation of putative V. harveyi, isolates were incubated on thiosulfate citrate bile salt sucrose agar plates for 24h, followed by selection of greenish colonies. Gram-negative and oxidase-positive colonies were subsequently confirmed by biochemical assays and the API 20E kit test system. Species-specific 16S rRNA and hemolysin genes were used to design V. harveyi-specific PCR primers. From 840 seawater samples, a total of 2 strains of V. harveyi were isolated from shellfish farm seawater. The two isolates were subjected to profiling against 16 antibiotics and found to be resistant to cephalothin, vancomycin, ampicillin, cefepime, cefotetan, and streptomycin. PMID:25066453

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

    Energy Technology Data Exchange (ETDEWEB)

    Byers, D.M.

    1987-05-01

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

  2. Genetic Determinants of Tetracycline Resistance in Vibrio harveyi

    Science.gov (United States)

    Teo, Jeanette W. P.; Tan, Theresa M. C.; Poh, Chit Laa

    2002-01-01

    Isolates of Vibrio harveyi, a prawn pathogen, have demonstrated multiple antibiotic resistance to commonly used antimicrobial agents, such as oxytetracycline. In this paper, we describe the cloning and characterization of two tetracycline resistance determinants from V. harveyi strain M3.4L. The first resistance determinant, cloned as a 4,590-bp fragment, was identical to tetA and flanking sequences encoded on transposon Tn10 from Shigella flexneri. The second determinant, cloned as a 3,358-bp fragment in pATJ1, contains two open reading frames, designated tet35 and txr. tet35 encodes a 369-amino-acid protein that was predicted to have nine transmembrane regions. It is a novel protein which has no homology to any other drug resistance protein but has low levels of homology (28%) to Na+/H+ antiporters. Transposon mutagenesis showed that tet35 and txr were required for tetracycline resistance in a heterologous Escherichia coli host. Tetracycline accumulation studies indicate that E. coli carrying tet35 and txr can function as an energy-dependent tetracycline efflux pump but is less efficient than TetA. PMID:11897587

  3. Quorum sensing positively regulates flagellar motility in pathogenic Vibrio harveyi.

    Science.gov (United States)

    Yang, Qian; Defoirdt, Tom

    2015-04-01

    Vibrios belonging to the Harveyi clade are among the major pathogens of aquatic organisms. Quorum sensing (QS) is essential for virulence of V. harveyi towards different hosts. However, most virulence factors reported to be controlled by QS to date are negatively regulated by QS, therefore suggesting that their impact on virulence is limited. In this study, we report that QS positively regulates flagellar motility. We found that autoinducer synthase mutants showed significantly lower swimming motility than the wild type, and the swimming motility could be restored by adding synthetic signal molecules. Further, motility of a luxO mutant with inactive QS (LuxO D47E) was significantly lower than that of the wild type and of a luxO mutant with constitutively maximal QS activity (LuxO D47A). Furthermore, we found that the expression of flagellar genes (both early, middle and late genes) was significantly lower in the luxO mutant with inactive QS when compared with wild type and the luxO mutant with maximal QS activity. Motility assays and gene expression also revealed the involvement of the quorum-sensing master regulator LuxR in the QS regulation of motility. Finally, the motility inhibitor phenamil significantly decreased the virulence of V. harveyi towards gnotobiotic brine shrimp larvae. PMID:24528485

  4. Structure of Vibrio cholerae ribosome hibernation promoting factor

    International Nuclear Information System (INIS)

    The X-ray crystal structure of ribosome hibernation promoting factor from V. cholerae has been determined at 2.0 Å resolution. The crystal was phased by two-wavelength MAD using cocrystallized cobalt. The X-ray crystal structure of ribosome hibernation promoting factor (HPF) from Vibrio cholerae is presented at 2.0 Å resolution. The crystal was phased by two-wavelength MAD using cocrystallized cobalt. The asymmetric unit contained two molecules of HPF linked by four Co atoms. The metal-binding sites observed in the crystal are probably not related to biological function. The structure of HPF has a typical β–α–β–β–β–α fold consistent with previous structures of YfiA and HPF from Escherichia coli. Comparison of the new structure with that of HPF from E. coli bound to the Thermus thermophilus ribosome [Polikanov et al. (2012 ▶), Science, 336, 915–918] shows that no significant structural changes are induced in HPF by binding

  5. Sensitivity of Vibrio cholerae cells to lethal and mutagenic effect of UV-irradiation mediated by plasmids

    International Nuclear Information System (INIS)

    The effect of UV-irradiation on Vibrio cholerae cells and its changes mediated by the plasmid R245 have been studied. Vibrio cholerae strains 569B and RV31 have been shown to be considerably more sensitive to lethal effect of UV-irradiation as compared with Escherichia coli and Salmonella typhimurium cells. Highly toxigenic strain 569B and practically atoxigenic strain RV31 have the same UV-sensitivity. Lethla effect of UV-irradiation on Vibrio cholerae cells is incresed when the irradiated cells are plated on enriched media. UV-induction of mutations was not registered in plasmidless strains of Vibrio cholerae. Plasmid R245 increase UV-resistance of vibrio cells and makes them UV-mutable

  6. Properties of Lactate Dehydrogenase in a Psychrophilic Marine Bacterium

    OpenAIRE

    Mitchell, P; Yen, H. C.; Mathemeier, P. F.

    1985-01-01

    Lactate dehydrogenase (EC 1.1.1.27) from Vibrio marinus MP-1 was purified 15-fold and ammonium activated. The optimum pH for pyruvate reduction was 7.4. Maximum lactate dehydrogenase activity occurred at 10 to 15 degrees C, and none occurred at 40 degrees C. The crude-extract enzyme was stable between 15 and 20 degrees C and lost 50% of its activity after 60 min at 45 degrees C. The partially purified enzyme was stable between 8 and 15 degrees C and lost 50% of its activity after 60 min at 30...

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

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Shigeki; Yonezawa, Yasushi [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Ibaraki 319-1195 (Japan); Ishibashi, Matsujiro [Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan); Matsumoto, Fumiko; Adachi, Motoyasu; Tamada, Taro [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Ibaraki 319-1195 (Japan); Tokunaga, Hiroko [Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan); Blaber, Michael [Florida State University, 1115 West Call Street, Tallahassee, FL 32306-4300 (United States); Tokunaga, Masao [Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan); Kuroki, Ryota, E-mail: kuroki.ryota@jaea.go.jp [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Ibaraki 319-1195 (Japan)

    2014-03-01

    In order to clarify the structural basis of the halophilic characteristics of an alkaline phosphatase derived from the moderate halophile Halomonas sp. 593 (HaAP), the tertiary structure of HaAP was determined to 2.1 Å resolution by X-ray crystallography. The structural properties of surface negative charge and core hydrophobicity were shown to be intermediate between those characteristic of halophiles and non-halophiles, and may explain the unique functional adaptation to a wide range of salt concentrations. 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 β-sheet core with 19 surrounding α-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{sup α} 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

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

    International Nuclear Information System (INIS)

    In order to clarify the structural basis of the halophilic characteristics of an alkaline phosphatase derived from the moderate halophile Halomonas sp. 593 (HaAP), the tertiary structure of HaAP was determined to 2.1 Å resolution by X-ray crystallography. The structural properties of surface negative charge and core hydrophobicity were shown to be intermediate between those characteristic of halophiles and non-halophiles, and may explain the unique functional adaptation to a wide range of salt concentrations. 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 β-sheet core with 19 surrounding α-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 (Cα 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

  9. Antagonistic effect of Pseudomonas aeruginosa isolates from various ecological niches on Vibrio species pathogenic to crustaceans

    Institute of Scientific and Technical Information of China (English)

    Prabhakaran Priyaja; Puthumana Jayesh; Neil Scolastin Correya; Balachandran Sreelakshmi; Naduthalmuriparambil S Sudheer; Rosamma Philip; Isaac Sarogeni Bright Singh

    2014-01-01

    Objective: To abrogate pathogenic vibrios in aquaculture by testing the potential of Pseudomonas isolates from fresh water, brackish and marine environments as probiotics.Methods:Antagonistic activity of the compound against 7 Vibrio spp. was performed. Influence of salinity on the production of pyocyanin and the toxicity was done through the compound using brine shrimp lethality assay. Molecular characterization was performed to confirm that the isolates werePseudomonas aeruginosa. Results: Salinity was found to regulate the levels of pyocyanin production, with 5-10 g/L as the optimum. All Pseudomonas isolates grew at salinities ranging from 5 to 70 g/L. Isolates of marine origin produced detectable levels of pyocyanin up to 45 g/L salinity. Brackish and freshwater isolates ceased to produce pyocyanin at salinities above 30 g/L and 20 g/L, respectively. Culture supernatants of all 5 Pseudomonas isolates possessed the ability to restrict the growth of Vibrio spp. and maximum antagonistic effect on Vibrio harveyi was obtained when they were grown at salinities of 5 to 10 g/L. The marine isolate MCCB117, even when grown at a salinity of 45 g/L possessed the ability to inhibit Vibrio spp.Conclusions:Purification and structural elucidation of antagonistic compound were carried out. ideal for application in freshwater, MCCB102 and MCCB103 in brackish water and MCCB117 and The present investigation showed that Pseudomonas aeruginosa MCCB119 would be MCCB118 in marine aquaculture systems as putative probiotics in the management of vibrios.

  10. Draft Genome Sequence of Oral Bacterium Streptococcus mutans JH1140

    OpenAIRE

    Escano, Jerome; Deng, Peng; Lu, Shi-En; Smith, Lief

    2016-01-01

    Streptococcus mutans JH1140 is an oral bacterium known to produce the bacteriocin mutacin 1140, and the strain has been genetically engineered to combat dental caries. Here, we report the 2.0-Mb draft genome of S. mutans JH1140. This genome provides new insights into the strain’s superior colonization properties and its utility in replacement therapy.

  11. Genome of a mosquito-killing bacterium decoded

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Researchers with the CAS Wuhan Institute of Virology (WHIOV) recently completed the genome sequencing of a mosquitocidal bacterium Bacillus shaericus C3-41. The feat, first of its kind in China, is expected to further promote the bio-control studies of mosquitoes.

  12. Rnf Genes in Purple Sulfur Bacterium Allochromatium vinosum

    OpenAIRE

    DİNÇTÜRK, H. Benan; DEMİR, Volkan

    2006-01-01

    Allochromatium vinosum is a photosynthetic, diazotrophic purple sulfur bacterium that oxidizes reduced sulfur compounds hydrogen sulfide, elemental sulfur and thiosulfide. In this article, we report the presence of rnf genes in Allochromatium vinosum, some of which have been reported to take part in nitrogen fixation in some species.

  13. Draft Genome Sequence of Oral Bacterium Streptococcus mutans JH1140

    Science.gov (United States)

    Escano, Jerome; Deng, Peng; Lu, Shi-En

    2016-01-01

    Streptococcus mutans JH1140 is an oral bacterium known to produce the bacteriocin mutacin 1140, and the strain has been genetically engineered to combat dental caries. Here, we report the 2.0-Mb draft genome of S. mutans JH1140. This genome provides new insights into the strain’s superior colonization properties and its utility in replacement therapy. PMID:27257196

  14. Identification of the genes encoding NAD(P)H-flavin oxidoreductases that are similar in sequence to Escherichia coli Fre in four species of luminous bacteria: Photorhabdus luminescens, Vibrio fischeri, Vibrio harveyi, and Vibrio orientalis.

    Science.gov (United States)

    Zenno, S; Saigo, K

    1994-01-01

    Genes encoding NAD(P)H-flavin oxidoreductases (flavin reductases) similar in both size and sequence to Fre, the most abundant flavin reductase in Escherichia coli, were identified in four species of luminous bacteria, Photorhabdus luminescens (ATCC 29999), Vibrio fischeri (ATCC 7744), Vibrio harveyi (ATCC 33843), and Vibrio orientalis (ATCC 33934). Nucleotide sequence analysis showed Fre-like flavin reductases in P. luminescens and V. fischeri to consist of 233 and 236 amino acids, respectively. As in E. coli Fre, Fre-like enzymes in luminous bacteria preferably used riboflavin as an electron acceptor when NADPH was used as an electron donor. These enzymes also were good suppliers of reduced flavin mononucleotide (FMNH2) to the bioluminescence reaction. In V. fischeri, the Fre-like enzyme is a minor flavin reductase representing < 10% of the total FMN reductase. That the V. fischeri Fre-like enzyme has no appreciable homology in amino acid sequence to the major flavin reductase in V. fischeri, FRase I, indicates that at least two different types of flavin reductases supply FMNH2 to the luminescence system in V. fischeri. Although Fre-like flavin reductases are highly similar in sequence to luxG gene products (LuxGs), Fre-like flavin reductases and LuxGs appear to constitute two separate groups of flavin-associated proteins. Images PMID:8206831

  15. Vibrio spp. and Salmonella spp., presence and susceptibility in crabs Ucides cordatus Vibrio spp. e Salmonella spp. em caranguejos, Ucides cordatus

    Directory of Open Access Journals (Sweden)

    Regine H.S.F. Vieira

    2004-08-01

    Full Text Available The presence of Vibrio spp. and Salmonella spp. in crabs marketed at the Bezerra de Menezes Ave., Fortaleza, State of Ceará, Brazil, was assessed between February and May, 2003. The number of individuals sampled in each one of the fifteen weekly samplings ranged between four and eight. Seven strains of Salmonella, from four different samplings, were identified, being five of them identified as serotype S. Senftenberg and two as S. Poona. All strains of Salmonella were sensitive to the tested anti-microbial drugs, with the exception of tetracycline and nalidixic acid, for which an intermediary sensibility was found. The MPN's for Vibrio ranged between 110/g and 110,000/g. Of the forty five Vibrio strains isolated from the crab samples, only 10 were identified up to the species level: two V. alginolyticus and eight V. parahaemolyticus. Bacteria belonging to the Enterobacteriaceae and Pseudomonaceae families were also identified, namely Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Pantoea agglomerans and Pseudomonas aeruginosa. The proper cooking of the animals is recommended in order to avoid problems for the consumers of this crustacean.Foram pesquisadas a presença de Vibrio spp. e de Salmonella spp. em caranguejos comercializados na Av. Bezerra de Menezes, Fortaleza, Ceará, Brasil, no período entre fevereiro e maio de 2003. O número de indivíduos em cada, das quinze coletas realizadas, semanalmente, variava entre quatro e oito dependendo do tamanho dos animais, totalizando um número de 90 (noventa animais examinados. Foram identificadas sete cepas de Salmonella spp. provenientes de quatro coletas: cinco foram identificadas como sorovar S. Senftenberg e duas como S. Poona. Todas as cepas de Salmonella, isoladas das amostras de caranguejos, apresentaram sensibilidade aos antimicrobianos testados, com exceção de tetraciclina e ácido nalidíxico para os quais elas apresentaram uma sensibilidade intermediária. Os NMPs

  16. Cerebral absces med Vibrio cholerae non-01 efter badning i dansk havvand

    DEFF Research Database (Denmark)

    Torp-Pedersen, Trine; Nielsen, Xiaohui Chen; Olsen, Katharina E P;

    2012-01-01

    We present the first case of intracerebral abscess after blood-borne infection with non-toxigenic Vibrio cholerae (non-01). The patient was a 66 year-old woman who was infected after swimming in Danish seawater during an unusually hot summer. She had predisposing haemochromatosis and a skin lesion...... on the ankle. We treated the patient with meropenem and ciprofloxacin for six weeks followed by ciprofloxacin for four weeks, and she recovered with hemiparesis and speech impairment. Marine Vibrio species may produce intracranial infection in predisposed individuals, even in temperate climate zones....

  17. Shotgun Genome Sequence of the Large Purple Photosynthetic Bacterium Rhodospirillum photometricum DSM122

    OpenAIRE

    Duquesne, K.; Sturgis, James N.

    2012-01-01

    Here, we present the shotgun genome sequence of the purple photosynthetic bacterium Rhodospirillum photometricum DSM122. The photosynthetic apparatus of this bacterium has been particularly well studied by microscopy. The knowledge of the genome of this oversize bacterium will allow us to compare it with the other purple bacterial organisms to follow the evolution of the photosynthetic apparatus.

  18. Survival of Vibrio cholerae O1 on fomites.

    Science.gov (United States)

    Farhana, Israt; Hossain, Zenat Zebin; Tulsiani, Suhella Mohan; Jensen, Peter Kjær Mackie; Begum, Anowara

    2016-09-01

    It is well established that the contamination sources of cholera causing bacteria, Vibrio cholerae, are water and food, but little is known about the transmission role of the fomites (surfaces that can carry pathogens) commonly used in households. In the absence of appropriate nutrients or growth conditions on fomites, bacteria have been known to assume a viable but non-culturable (VBNC) state after a given period of time. To investigate whether and when V. cholerae O1 assumes such a state, this study investigated the survival and viable quantification on a range of fomites such as paper, wood, glass, plastic, cloth and several types of metals under laboratory conditions. The fomites were inoculated with an outbreak strain of V. cholerae and its culturability was examined by drop plate count method at 30 min intervals for up to 6 h. For molecular detection, the viable/dead stain ethidium monoazide (EMA) which inhibits amplification of DNA from dead cells was used in combination with real-time polymerase chain reaction (EMA-qPCR) for direct quantitative analyses of viable V. cholerae at 2, 4, 6, 24 h and 7 day time intervals. Results showed that V. cholerae on glass and aluminum surfaces lost culturability within one hour after inoculation but remained culturable on cloth and wood for up to four hours. VBNC V. cholerae on dry fomite surfaces was detected and quantified by EMA-qPCR even 7 days after inoculation. In conclusion, the prolonged survival of V. cholerae on various household fomites may play vital role in cholera transmission and needs to be further investigated. PMID:27430513

  19. RpoS controls the Vibrio cholerae mucosal escape response.

    Directory of Open Access Journals (Sweden)

    Alex Toftgaard Nielsen

    2006-10-01

    Full Text Available Vibrio cholerae causes a severe diarrhoeal disease by secreting a toxin during colonization of the epithelium in the small intestine. Whereas the initial steps of the infectious process have been intensively studied, the last phases have received little attention. Confocal microscopy of V. cholerae O1-infected rabbit ileal loops captured a distinctive stage in the infectious process: 12 h post-inoculation, bacteria detach from the epithelial surface and move into the fluid-filled lumen. Designated the "mucosal escape response," this phenomenon requires RpoS, the stationary phase alternative sigma factor. Quantitative in vivo localization assays corroborated the rpoS phenotype and showed that it also requires HapR. Expression profiling of bacteria isolated from ileal loop fluid and mucus demonstrated a significant RpoS-dependent upregulation of many chemotaxis and motility genes coincident with the emigration of bacteria from the epithelial surface. In stationary phase cultures, RpoS was also required for upregulation of chemotaxis and motility genes, for production of flagella, and for movement of bacteria across low nutrient swarm plates. The hapR mutant produced near-normal numbers of flagellated cells, but was significantly less motile than the wild-type parent. During in vitro growth under virulence-inducing conditions, the rpoS mutant produced 10- to 100-fold more cholera toxin than the wild-type parent. Although the rpoS mutant caused only a small over-expression of the genes encoding cholera toxin in the ileal loop, it resulted in a 30% increase in fluid accumulation compared to the wild-type. Together, these results show that the mucosal escape response is orchestrated by an RpoS-dependent genetic program that activates chemotaxis and motility functions. This may furthermore coincide with reduced virulence gene expression, thus preparing the organism for the next stage in its life cycle.

  20. Complete topology of the RNF complex from Vibrio cholerae.

    Science.gov (United States)

    Hreha, Teri N; Mezic, Katherine G; Herce, Henry D; Duffy, Ellen B; Bourges, Anais; Pryshchep, Sergey; Juarez, Oscar; Barquera, Blanca

    2015-04-21

    RNF is a redox-driven ion (Na(+) and in one case possibly H(+)) transporter present in many prokaryotes. It has been proposed that RNF performs a variety of reactions in different organisms, delivering low-potential reducing equivalents for specific cellular processes. RNF shares strong homology with the Na(+)-pumping respiratory enzyme Na(+)-NQR, although there are significant differences in subunit and redox cofactor composition. Here we report a topological analysis of the six subunits of RNF from Vibrio cholerae. Although individual subunits from other organisms have previously been studied, this is the first complete, experimentally derived, analysis of RNF from any one source. This has allowed us to identify and confirm key properties of RNF. The putative NADH binding site in RnfC is located on the cytoplasmic side of the membrane. FeS centers in RnfB and RnfC are also located on the cytoplasmic side. However, covalently attached FMNs in RnfD and RnfG are both located in the periplasm. RNF also contains a number of acidic residues that correspond to functionally important groups in Na(+)-NQR. The acidic residues involved in Na(+) uptake and many of those implicated in Na(+) translocation are topologically conserved. The topology of RNF closely matches the topology represented in the newly published structure of Na(+)-NQR, consistent with the close relation between the two enzymes. The topology of RNF is discussed in the context of the current structural model of Na(+)-NQR, and the proposed functionality of the RNF complex itself. PMID:25831459

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

    Science.gov (United States)

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

    2011-05-01

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

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

    International Nuclear Information System (INIS)

    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.

  3. Antimicrobial Resistance Patterns of Isolated Vibrio cholerae Strains

    Directory of Open Access Journals (Sweden)

    Hajia

    2016-02-01

    Full Text Available Background Cholera is a potentially life-threatening acute diarrheal disease caused by the toxigenic bacteria, Vibrio cholerae. Antibiotics should be selected using local antibiotic susceptibility testing patterns. Objectives This study was performed to identify the patterns of antimicrobial resistance in isolates collected from laboratory-confirmed cases of cholera during three years, from 2011 to 2013. Materials and Methods All isolates at the Health Reference Laboratory were tested by the Minimum Inhibitory Concentration (MIC Test using Liofilchem against ciprofloxacin, nalidixic acid, cefixime, ampicillin, tetracycline, trimethoprim-sulfamethoxazole, and erythromycin. The following organisms were used as quality control strains for MIC E-testing; Escherichia coli (ATCC 25922, Staphylococcus aureus (ATCC 29213, and Pseudomonas aeruginosa (ATCC 27853. Results Results of susceptibility testing showed complete sensitivity to ciprofloxacin, cefixime and amplicillin for both isolated Inaba and Ogawa serotypes except all isolated Inaba serotypes from year 2011, which were resistant to cefixime. These resistant Inaba serotypes were not isolated in the next year. Inaba serotypes showed an increased resistance rate of up to 100% to nalidixic acid, tetracycline and trimethoprim-sulfamethaxazone, while Ogawa serotypes were 100% sensitive at the end of year 2013. The susceptibility pattern of erytromycine was similar in these two types. Sensitivity to erythromycin was decreased in both Inaba and Ogawa serotypes. Conclusions The analyzed results indicate that tetracycline should not be considered as a first line antibiotic therapy for patients infected with Ogawa serotypes. Also, national guidelines for confirmation of cholera should be improved by responsible authorities to cover new resistance during outbreaks.

  4. Biological deinking of inkjet-printed paper using Vibrio alginolyticus and its enzymes

    Digital Repository Service at National Institute of Oceanography (India)

    Mohandass, C.; Raghukumar, C.

    by growing the bacterium in the pulp of 3-6 % consistency suspended in sea water. Immobilized bacterial cells in sodium alginate beads also were able to decolorize this pulp within 72 h. The cell-free culture supernatant of the bacterium grown in nutrient...

  5. Occurrence of potentially pathogenic Vibrio species in raw, processed, and ready-to-eat seafood and seafood products

    Directory of Open Access Journals (Sweden)

    Thararat Chitov

    2009-02-01

    Full Text Available This study investigated the occurrence (by means of the presence-absence test and level (by means of a plate count technique of selected potentially pathogenic Vibrio species in processed and ready-to-eat seafood, and some raw seafood normally used as raw materials or ingredients in these products, that were commercially available in Chiang Mai, Thailand. The level of Vibrio in raw seafood was found to range from 50 to 104 cfu/g. V. alginolyticus was the most frequently found species, followed by V. parahaemolyticus, V. cholerae, V. mimicus, and V. vulnificus, in that order. Processed and ready-to-eat products were contaminated with at least one of the potentially pathogenic vibrios at significant frequencies (25 and 17.5 % of samples, respectively, with the level as high as 103 to 104 per gram in some samples. Incidences of vibrios revealed by the presence-absence test were significantly higher than those revealed by the plate count assay. These data point to the hazard potential relating to Vibrio in processed and ready-to-eat seafood and the need to strictly apply preventive measures against Vibrio gastroenteritis through consumption of these food products. They also suggest that analytical methods used in food safety evaluation in relation to potentially hazardous Vibrio species should be carefully considered.

  6. Vibrio vulnificus specie isolation in series blood culture. A case report. Aislamiento de especie de Vibrio vulnificus en hemocultivos seriados. Reporte de un caso.

    Directory of Open Access Journals (Sweden)

    Annia Alvarado Borges

    2004-08-01

    Full Text Available This papers contains a report of a case with Vibrio vulnificuls, gram negative micro organism that ferments carbohydrates and that is positive to the oxidase test and halophile in a patient with history of heart and liver disease who was assisted at the Intensive Care Emergency Unit ( ICU of the ¨Dr. Gustavo Aldereguía Lima¨ University Hospital in July 2003. Thy symptoms were: oedema in lower limbs, orthopnea, chest pain that was interpreted as a case of pneumonia and a Myocardial Infarction. This patient progresses rapidly to cardiac arrest, is reanimated , and is admitted at the ICU with control pressuremetric ventilation. Vibrio Vulnificuls was isolated with a conventional diagnosis from hemo cultures. Anti microbial Susceptibility tests , the micro organism was susceptible to tetracycline, sulphaprim, aztreonam, ampicillin and was resistant to chloranphenicol.

    Se reporta un caso de sepsis por Vibrio vulnificus en un paciente con antecedentes de insuficiencia cardiaca y hepatopatía, atendido en el servicio de Cuidados Intensivos de Emergencia del Hospital Universitario ¨Dr. Gustavo Aldereguía Lima¨, en julio de 2003. Los síntomas fueron: edema en miembros inferiores, ortopnea y dolor precordial que se interpretaron como bronconeumonía extrahospitalaria e infarto agudo del miocardio. Evoluciona rápidamente al paro cardiorrespiratorio, se reanima e ingresa en Cuidados Intensivos con ventilación presiométrica controlada. Se aisló Vibrio vulnificus por diagnóstico convencional desde hemocultivos. En las pruebas de susceptibilidad antimicrobiana resultó sensible a tetraciclina, sulfaprim, aztreonam, ampicillin y resistente a cloranfenicol.

  7. Vibrio spp. and Salmonella spp., presence and susceptibility in crabs Ucides cordatus Vibrio spp. e Salmonella spp. em caranguejos, Ucides cordatus

    OpenAIRE

    Regine H.S.F. Vieira; Elenice Araújo de Lima; Dannielle Batista Rolim Sousa; Eliane Falavina dos Reis; Renata Garcia Costa; Dália dos Prazeres Rodrigues

    2004-01-01

    The presence of Vibrio spp. and Salmonella spp. in crabs marketed at the Bezerra de Menezes Ave., Fortaleza, State of Ceará, Brazil, was assessed between February and May, 2003. The number of individuals sampled in each one of the fifteen weekly samplings ranged between four and eight. Seven strains of Salmonella, from four different samplings, were identified, being five of them identified as serotype S. Senftenberg and two as S. Poona. All strains of Salmonella were sensitive to the tested ...

  8. Isolation and characterization of a new species of Vibrio-Vibrio olivaceus sp.nov. from diseased flounder (Paralichthys olivaceus temminck et schlegel)

    Institute of Scientific and Technical Information of China (English)

    Fang Hai; Zhang Xiao-jun; Chen Cuizhen; Zhan Wenbin; Jin Xiaomin

    2005-01-01

    One kind of pathogenic bacteria was isolated from diseased (or dead) flounder (Paralichthys olivaceus L.) which expressed bacterial septicaemia. The phenotyic information of the 10 pure cultures was studied extensively, including morphological characteristics, colony characteristics in different media, physiological and biochemical characteristics, and the mol%G+C ratio of the DNA for representative strain. The results showed that the isolates belonged to a new species of Vibrio. In addition, the representative strains have been re-checked by China Center for Type Culture Collection (CCTCC), the results were the same as ours, the examined strains were also regarded as a new species of Vibrio, and designated as Vibrio olivaceus sp.nov. by its isolated fish (Paralichthys olivaceus) based on its biological properties following Rules of International Code of Nomenclature of Bacteria. In the same time, we conducted studies on the serum homology of isolates, pathogenicity of isolates by experimental infection. The results showed that all the isolates were of serologic similarity and the isolates have strong pathogenicity to flounder. Inspection to pure cultures and isolates from liver of moribund fish from infection experiment by fluorescent antibody technique showed the feasibility of fluorescent antibody technique as an auxiliary method of examination.

  9. The Vibrio parahaemolyticus-infecting bacteriophage qdvp001: genome sequence and endolysin with a modular structure.

    Science.gov (United States)

    Wang, Weiyu; Li, Mengzhe; Lin, Hong; Wang, Jingxue; Mao, Xiangzhao

    2016-10-01

    Vibrio parahaemolyticus, a marine pathogen, is a causative agent of gastroenteritis in humans after consumption of contaminated seafood. In recent years, infections with V. parahaemolyticus have become an increasingly frequent factor in microbial food poisoning; therefore, it is urgent to figure out ways to control Vibrio parahaemolyticus. Endolysins, lytic enzymes encoded by bacteriophages, have been regarded as a therapeutic alternative to antibiotics in control of bacterial growth and have been successfully utilized in various areas. Here, we report the full genome sequence of the novel phage qdvp001, which lyses Vibrio parahaemolyticus 17802. The qdvp001 genome consists of a 134,742-bp DNA with a G+C content of 35.35 % and 227 putative open reading frames. Analysis revealed that the qdvp001 open reading frames encoded various putative functional proteins with a putative endolysin gene (ORF 60). No holin genes were identified in qdvp001. ORF 60 was cloned and expressed. The results showed that the purified endolysin Lysqdvp001 had a high hydrolytic activity toward Vibrio parahaemolyticus and a broader spectrum compared to that of the parental bacteriophage qdvp001. Thus, purified endolysin Lysqdvp001 has a potential to be used as an antibacterial agent in the future. PMID:27376376

  10. Comparison of Vibrio parahaemolyticus grown in estuarine water and rich medium.

    OpenAIRE

    Pace, J; Chai, T J

    1989-01-01

    Cell envelope composition and selected physiological traits of Vibrio parahaemolyticus were studied in regard to the Kanagawa phenomenon and growth conditions. Cell envelopes were prepared from cells cultured in Proteose Peptone-beef extract (Difco Laboratories, Detroit, Mich.) medium or filtered estuarine water. Protein, phospholipid, and lipopolysaccharide contents varied with culture conditions. The phospholipids present in the cell envelopes were identified as phosphatidylethanolamine, ph...

  11. Vibrio galatheae sp. nov., a novel member of the Vibrionaceae family isolated from the Solomon Sea

    DEFF Research Database (Denmark)

    Giubergia, Sonia; Machado, Henrique; Mateiu, Ramona Valentina;

    2015-01-01

    Based on genetic, chemotaxonomic and phenotypic characteristics, a novel species belonging to the genus Vibrio is described. The facultative anaerobic strain S2757T was isolated from a mussel collected in the Solomon Sea (Solomon Islands). Phylogenetic analyses based on sequences of 16S r...

  12. A Two-Step Synthesis of Virstatin, a Virulence Inhibitor of "Vibrio cholerae"

    Science.gov (United States)

    McDonald, Chriss E.

    2009-01-01

    Virstatin, an "N"-butanoic acid substituted naphthalimide, inhibits the ability of "Vibrio cholerae" to cause disease. A three-week experiment involving synthesis, purification, and spectral characterization of this compound is described. This experiment is appropriate for organic chemistry. It has been performed with three lab sections of about…

  13. Gene dosage compensation calibrates four regulatory RNAs to control Vibrio cholerae quorum sensing

    DEFF Research Database (Denmark)

    Svenningsen, Sine L; Tu, Kimberly C; Bassler, Bonnie L

    2009-01-01

    Quorum sensing is a mechanism of cell-to-cell communication that allows bacteria to coordinately regulate gene expression in response to changes in cell-population density. At the core of the Vibrio cholerae quorum-sensing signal transduction pathway reside four homologous small RNAs (sRNAs), named...

  14. Crystallization of the HigBA2 toxin-antitoxin complex from Vibrio cholerae

    DEFF Research Database (Denmark)

    Hadǽi, San; Garcia-Pino, Abel; Martinez-Rodriguez, Sergio;

    2013-01-01

    The genome of Vibrio cholerae encodes two higBA toxin-antitoxin (TA) modules that are activated by amino-acid starvation. Here, the TA complex of the second module, higBA2, as well as the C-terminal domain of the corresponding HigA2 antitoxin, have been purified and crystallized. The HigBA2 complex...

  15. A checkpoint control orchestrates the replication of the two chromosomes of Vibrio cholerae

    DEFF Research Database (Denmark)

    Val, Marie-Eve; Marbouty, Martial; Martins, Francisco de Lemos;

    2016-01-01

    important differences between plasmids and chromosomes is that the latter replicate during a defined period of the cell cycle, ensuring a single round of replication per cell. Vibrio cholerae carries two circular chromosomes, Chr1 and Chr2, which are replicated in a well-orchestrated manner with the cell...

  16. Comparative genomics of 274 Vibrio cholerae genomes reveals mobile functions structuring three niche dimensions

    NARCIS (Netherlands)

    Dutilh, Bas E; Thompson, Cristiane C; Vicente, Ana C P; Marin, Michel A; Lee, Clarence; Silva, Genivaldo G Z; Schmieder, Robert; Andrade, Bruno G N; Chimetto, Luciane; Cuevas, Daniel; Garza, Daniel R; Okeke, Iruka N; Aboderin, Aaron Oladipo; Spangler, Jessica; Ross, Tristen; Dinsdale, Elizabeth A; Thompson, Fabiano L; Harkins, Timothy T; Edwards, Robert A

    2014-01-01

    BACKGROUND: Vibrio cholerae is a globally dispersed pathogen that has evolved with humans for centuries, but also includes non-pathogenic environmental strains. Here, we identify the genomic variability underlying this remarkable persistence across the three major niche dimensions space, time, and h

  17. Heterogeneity among isolates of Vibrio vulnificus recovered from eels ( Anguilla anguilla ) in Denmark

    DEFF Research Database (Denmark)

    Høi, L.; Dalsgaard, Inger; DePaola, A.;

    1998-01-01

    The findings of this study demonstrate that Vibrio vulnificus isolates recovered from diseased eels in Denmark are heterogeneous as shown by O serovars, capsule types, ribotyping, phage typing, and plasmid profiling, The study: includes 85 V. vulnificus isolates isolated from the gills, intestinal...

  18. Role of Flagella in Virulence of the Coral Pathogen Vibrio coralliilyticus▿ †

    OpenAIRE

    Meron, Dalit; Efrony, Rotem; Johnson, Wesley R; Schaefer, Amy L.; Morris, Pamela J.; Rosenberg, Eugene; Greenberg, E. Peter; Banin, Ehud

    2009-01-01

    A recently available transposition system was utilized to isolate a nonmotile mutant of the coral-bleaching pathogen Vibrio coralliilyticus. The mutation was localized to the fhlA gene, and the mutant lacked flagella. The flhA mutant was unable to exhibit chemotaxis toward coral mucus or to adhere to corals and subsequently cause infection.

  19. csrA Inhibits the Formation of Biofilms by Vibrio vulnificus▿

    OpenAIRE

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

    2008-01-01

    PCR screening of the shellfish-borne pathogen Vibrio vulnificus revealed csrA-negative strains, and these strains formed increased biofilm compared to csrA-positive strains. Complementation in trans with csrA resulted in reduced biofilm formation, similar to that by csrA+ strains. Our results provide evidence that csrA inhibits biofilm formation in V. vulnificus.

  20. Occurrence of Vibrio cholerae non 01 and their dispersion phenomena in the coastal waters at Mangalore

    Digital Repository Service at National Institute of Oceanography (India)

    Sreeja, S.; Raveendran, O.

    , PA., Weaver, R.E. & Hollis, D.G. (1980) Ann. Rev-Microbiol, 3, p.341 Colwell, R.R. (1984) Vibrios in the envt, p.l (John Wiley & Sons, New York) Colwell, R.R. & Kaper, J. (1997) Science, p.394 Iyer, T.S.G., Varma, P.RG., Agnes J. M. & Zacharia, S...

  1. Novel AI-2 quorum sensing inhibitors in Vibrio harveyi identified through structure-based virtual screening.

    Science.gov (United States)

    Zhu, Peng; Peng, Hanjing; Ni, Nanting; Wang, Binghe; Li, Minyong

    2012-10-15

    In this letter, a high-throughput virtual screening was accomplished to identify potent inhibitors against AI-2 quorum sensing on the basis of Vibrio harveyi LuxPQ crystal structure. Seven compounds were found to inhibit AI-2 quorum sensing with IC(50) values in the micromolar range, and presented low cytotoxicity or no cytotoxicity in V. harveyi. PMID:22963763

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

    Science.gov (United States)

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

    2015-01-01

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

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

    Science.gov (United States)

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2012-12-01

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

  5. PREVALENCE AND IDENTIFICATION OF VIBRIO SPP. ISOLATED ON AQUACULTURED GILTHEAD SEA BREAM

    Directory of Open Access Journals (Sweden)

    C. Scarano

    2011-01-01

    Full Text Available The aim of the study was to investigate the prevalence of Vibrio spp isolated from gilthead sea bream (Sparus aurata farmed on sea cages and to identify and characterize the pathogen by molecular techniques. Eighty fish were collected from two hatcheries located on the North-Est Sardinian Mediterranean coast, and microbiological analysis were performed on different body parts such as skin, gills, muscle and intestinal tract. Subsequently 100 pure colonies with typical morphology and phenotypic characteristics were selected and submitted to the molecular identification. The analysis on the prevalence of Vibrio spp showed the effect of the hatchery rearing system (P<0.001, of the date of sampling (P<0.001, and of the body part (P<0.001. All the strains selected were confirmed to be members of the genus Vibrio spp by the molecular method/techinique/identification, whereas the rpoA gene sequence analyses allowed to identify 89 strains belonging to the species Vibrio harveyi, 6 to V. diabolicus, 2 to V. parahaemolyticus and 1 to V. mediterranei.

  6. Antimicrobial Drug Resistance of Vibrio cholerae, Democratic Republic of the Congo

    OpenAIRE

    Miwanda, B.; Moore, S.; Muyembe, J.-, J; Nguefack-Tsague, G.; Kabangwa, IK; Ndjakani, DY; Mutreja, A; Thomson, N.; Thefenne, H; Garnotel, E; Tshapenda, G; Kakongo, DK; Kalambayi, G; Piarroux, R

    2015-01-01

    We analyzed 1,093 Vibrio cholerae isolates from the Democratic Republic of the Congo during 1997-2012 and found increasing antimicrobial drug resistance over time. Our study also demonstrated that the 2011-2012 epidemic was caused by an El Tor variant clonal complex with a single antimicrobial drug susceptibility profile.

  7. Draft Genome Sequences of Two Vibrio splendidus Strains, Isolated from Seagrass Sediment.

    Science.gov (United States)

    Lee, Ruth D; Jospin, Guillaume; Lang, Jenna M; Eisen, Jonathan A; Coil, David A

    2016-01-01

    Here, we present the draft genome sequences of Vibrio splendidus UCD-SED7 and UCD-SED10 (phylum Proteobacteria). These strains were isolated from sediment surrounding Zostera marina roots near the UC Davis Bodega Marine Laboratory (Bodega, Bay, California). These assemblies contain 5,334,236 bp and 5,904,824 bp, respectively. PMID:26893436

  8. Mapping of a gene that regulates hemolysin production in Vibrio cholerae.

    OpenAIRE

    von Mechow, S; Vaidya, A B; Bramucci, M G

    1985-01-01

    A gene that regulates the hemolysin structural gene (hly) was found to be tightly linked to the tox-1000 locus of Vibrio cholerae RJ1 and separated from hly by a large section of the V. cholerae genetic map. This hemolysin regulatory gene was designated hlyR.

  9. Vibrio cholerae tolC Is Required for Bile Resistance and Colonization

    OpenAIRE

    Bina, James E.; Mekalanos, John J.

    2001-01-01

    TolC and its homologues are outer membrane proteins that are essential for the transport of many molecules across the cell envelope. In this study we characterized the gene encoding Vibrio cholerae TolC. V. cholerae tolC mutants failed to secrete the RTX cytotoxin, were hypersensitive to antimicrobial agents, and were deficient in intestinal colonization.

  10. Vibrio cholerae O1 from superficial water of the Tucunduba Stream, Brazilian Amazon

    OpenAIRE

    Sá, L.L.C.; Vale, E.R.V.; Garza, D.R.; A.C.P. Vicente

    2012-01-01

    Isolation and genetic characterization of an environmental Vibrio cholerae O1 from the Amazon is reported. This strain lacks two major virulence factors - CTX and TCP - but carries other genes related to virulence. Genetic similarity with epidemic strains is evaluated and the importance of V. cholerae surveillance in the Amazon is emphasized.

  11. Use of vaginal tampons in sewer surveys for non-O1. Vibrio cholerae.

    OpenAIRE

    Pazzaglia, G; Lesmana, M; Tjaniadi, P; Subekti, D; Kay, B.

    1993-01-01

    Vaginal tampons were shown to be a practical alternative to conventional Moore swabs for isolating Vibrio cholerae from sewage. Associated laboratory investigations demonstrated improved isolation of V. cholerae by using 12- or 18-h enrichments in alkaline peptone water, in comparison with 6-h enrichments, when cultures were incubated at ambient temperatures.

  12. Pathogenicity comparison of high and low virulent strains of Vibrio scophthalmi in olive flounder (Paralichthys olivaceus)

    Science.gov (United States)

    Vibrio scophthalmi is a bacterial pathogen of olive flounder (Paralichthys olivaceus) and virulence is different from various strains. There is not information available on pathogenicity to olive flounder caused by different strains of V. scophthalmi. In this study, the high and low virulent strains...

  13. Tandem heterocyclization domains in a nonribosomal peptide synthetase essential for siderophore biosynthesis in Vibrio anguillarum

    NARCIS (Netherlands)

    Di Lorenzo, M.; Stork, M.; Naka, H.; Tolmasky, M.E.; Crosa, J.H.

    2008-01-01

    Anguibactin, the siderophore produced by Vibrio anguillarum 775, is synthesized via a nonribosomal peptide synthetase (NRPS) mechanism. Most of the genes required for anguibactin biosynthesis are harbored by the pJM1 plasmid. Complete sequencing of this plasmid identified an orf encoding a 108 kDa p

  14. Indole-positive Vibrio vulnificus isolated from disease outbreaks on a Danish eel farm

    DEFF Research Database (Denmark)

    Dalsgaard, Inger; Høi, L.; Siebeling, R.J.; Dalsgaard, A.

    1999-01-01

    Vibrio vulnificus was isolated in 1996 from 2 disease outbreaks on a Danish eel farm which used brackish water. A characteristic clinical sign was extensive, deep muscle necrosis in the head region. V. vulnificus was isolated from kidney, mucus, spleen, gill and intestine of diseased eels. Thirty...

  15. Non-lethal heat shock protects gnotobiotic Artemia franciscana larvae against virulent Vibrios

    OpenAIRE

    Yik Sung, Y.; Van Damme, E.J.M.; Sorgeloos, P.; Bossier, P

    2007-01-01

    Brine shrimp Artemia were exposed under gnotobiotic conditions to a non-lethal heat shock (NLHS) from 28 to 32, 37 and 40°C. Different recovery periods (2, 6, 12 and 24 h) and different heat-exposure times (15, 30, 45 and 60 min) were tested. After these NLHS, Artemia was subsequently challenged with Vibrio. Challenge tests were performed in stressed and unstressed nauplii at concentrations of 107 cells ml-1 of pathogenic bacteria, Vibrio campbellii and Vibrio proteolyticus. A NLHS with an op...

  16. Simple conjugation and outgrowth procedures for tagging vibrios with GFP, and factors affecting the stable expression of the gfp tag

    OpenAIRE

    Sawabe, T.; Fukui, Y.; Stabb, E.V.

    2006-01-01

    Aim: Our goal was to develop a simple system for tagging wild-type marine bacteria with gfp. Methods and Results: Escherichia coli strain CC118λpir carrying the conjugative helper plasmid pEVS104 and the gfp-containing plasmid pKV111 was used to transfer gfp to Vibrio recipients. Four different media were tested for their ability to support the growth of recipients, but not the E. coli donor, to allow powerful enrichment of gfp-tagged wild-type vibrios from mating mixes. Forty-three vibrio...

  17. Coordination of the arc regulatory system and pheromone-mediated positive feedback in controlling the Vibrio fischeri lux operon.

    Directory of Open Access Journals (Sweden)

    Alecia N Septer

    Full Text Available Bacterial pheromone signaling is often governed both by environmentally responsive regulators and by positive feedback. This regulatory combination has the potential to coordinate a group response among distinct subpopulations that perceive key environmental stimuli differently. We have explored the interplay between an environmentally responsive regulator and pheromone-mediated positive feedback in intercellular signaling by Vibrio fischeri ES114, a bioluminescent bacterium that colonizes the squid Euprymna scolopes. Bioluminescence in ES114 is controlled in part by N-(3-oxohexanoyl-L-homoserine lactone (3OC6, a pheromone produced by LuxI that together with LuxR activates transcription of the luxICDABEG operon, initiating a positive feedback loop and inducing luminescence. The lux operon is also regulated by environmentally responsive regulators, including the redox-responsive ArcA/ArcB system, which directly represses lux in culture. Here we show that inactivating arcA leads to increased 3OC6 accumulation to initiate positive feedback. In the absence of positive feedback, arcA-mediated control of luminescence was only ∼2-fold, but luxI-dependent positive feedback contributed more than 100 fold to the net induction of luminescence in the arcA mutant. Consistent with this overriding importance of positive feedback, 3OC6 produced by the arcA mutant induced luminescence in nearby wild-type cells, overcoming their ArcA repression of lux. Similarly, we found that artificially inducing ArcA could effectively repress luminescence before, but not after, positive feedback was initiated. Finally, we show that 3OC6 produced by a subpopulation of symbiotic cells can induce luminescence in other cells co-colonizing the host. Our results suggest that even transient loss of ArcA-mediated regulation in a sub-population of cells can induce luminescence in a wider community. Moreover, they indicate that 3OC6 can communicate information about both cell density

  18. First study of Vibrios in larval cultures of pullet carpet shell clam (Venerupis corrugata in hatchery

    Directory of Open Access Journals (Sweden)

    Javier Dubert Pérez

    2014-07-01

    Full Text Available Protocol for hatchery culture of the pullet carpet shell clam Venerupis corrugata spat is currently under development, as the only reliable means of providing spat to replenish natural beds or to support aquaculture activities. Among other variables, the microbiota has been demonstrated to be critical for successful bivalve culture. Shellfish hatcheries are hindered by fatal outbreaks of disease, regardless the bivalve species. These mass mortalities are mainly caused by opportunistic bacteria belonging to genus Vibrio and constitute one bottleneck for this economic activity. Different species, as V. tubiashii, V. pectenicida, V. splendidus, V. neptunius, V. ostreicida and V. bivalvicida, have been identified as responsible of mortalities in hatchery-reared larvae, affecting a wide range of bivalves. This is the first report of the microbiota associated with larval cultures of the pullet carpet shell clam. We present the results of the microbiological analyses of two larval cultures of pullet carpet shell reared in the Centro de Investigacións Mariñas (CIMA, Xunta de Galicia de Ribadeo (Galicia, NW Spain following the procedures developed in the institution. Each batch, A and B, was obtained from broodstocks collected in natural environment but in different geographical locations, the stock A (SW Galicia and the stock B (NW Galicia. Previous records of mortalities led us to divide each batch in two. One sub-batch (A1 and B1 was cultured following the routine procedures. Antibiotic was experimentally added to the other sub-batch (A2 and B2 with the aim of evaluating the effects on the culturable bacterial population (total marine bacteria and presumptive vibrios and on larval survival. Chloramphenicol, formerly the most commonly used antibiotic in bivalve hatcheries, was supplied with each change of seawater during larval development. Microbiological samples of broodstock, larvae and seawater in culture tanks were taken and processed

  19. A Streamlined Strategy for Biohydrogen Production with an Alkaliphilic Bacterium

    Energy Technology Data Exchange (ETDEWEB)

    Elias, Dwayne A [ORNL; Wall, Judy D. [University of Missouri; Mormile, Dr. Melanie R. [Missouri University of Science and Technology; Begemann, Matthew B [University of Wisconsin, Madison

    2012-01-01

    Biofuels are anticipated to enable a shift from fossil fuels for renewable transportation and manufacturing fuels, with biohydrogen considered attractive since it could offer the largest reduction of global carbon budgets. Currently, biohydrogen production remains inefficient and heavily fossil fuel-dependent. However, bacteria using alkali-treated biomass could streamline biofuel production while reducing costs and fossil fuel needs. An alkaliphilic bacterium, Halanaerobium strain sapolanicus, is described that is capable of biohydrogen production at levels rivaling neutrophilic strains, but at pH 11 and hypersaline conditions. H. sapolanicus ferments a variety of 5- and 6- carbon sugars derived from hemicellulose and cellulose including cellobiose, and forms the end products hydrogen and acetate. Further, it can also produce biohydrogen from switchgrass and straw pretreated at temperatures far lower than any previously reported and in solutions compatible with growth. Hence, this bacterium can potentially increase the efficiency and efficacy of biohydrogen production from renewable biomass resources.

  20. Rock Phosphate Solubilization Mechanisms of One Fungus and One Bacterium

    Institute of Scientific and Technical Information of China (English)

    LIN Qi-mei; ZHAO Xiao-rong; ZHAO Zi-juan; LI Bao-guo

    2002-01-01

    Many microorganisms can dissolve the insoluble phosphates like apatite. However, the mechanisms are still not clear. This study was an attempt to investigate the mechanisms of rock phosphate solubilization by an Aspergillus 2TCiF2 and an Arthrobacter1TCRi7. The results indicated that the fungus produced a large amount of organic acids, mainly oxalic acid. The total quantity of the organic acids produced by the fungus was 550 times higher than that by the bacterium. Different organic acids had completely different capacities to solubilize the rock. Oxalic acid and citric acid had stronger capacity to dissolve the rock than malic acid, tartaric acid, lactic acid, acetic acid, malonic acid and succinic acid. The fungus solubilized the rock through excreting both proton and organic acids. The rock solubilization of the bacterium depended on only proton.

  1. A physical map of the hyperthermophilic bacterium Aquifex pyrophilus chromosome.

    OpenAIRE

    Shao, Z; Mages, W; Schmitt, R.

    1994-01-01

    A genomic map of the hyperthermophilic hydrogen-oxidizing bacterium Aquifex pyrophilus was established with NotI (GC/GGCCGC), SpeI (A/CTAGT), and XbaI (T/CTAGA). Linking clones and cross-hybridization of restriction fragments revealed a single circular chromosome of 1.6 Mbp. A single flagellin gene and six rRNA gene units were located on this map by Southern hybridization.

  2. Isolation of a Bacterium Capable of Degrading Peanut Hull Lignin

    OpenAIRE

    Kerr, Thomas J.; Kerr, Robert D.; Benner, Ronald

    1983-01-01

    Thirty-seven bacterial strains capable of degrading peanut hull lignin were isolated by using four types of lignin preparations and hot-water-extracted peanut hulls. One of the isolates, tentatively identified as Arthrobacter sp., was capable of utilizing all four lignin preparations as well as extracted peanut hulls as a sole source of carbon. The bacterium was also capable of degrading specifically labeled [14C]lignin-labeled lignocellulose and [14C]cellulose-labeled lignocellulose from the...

  3. The Vibrio cholerae cytolysin promotes chloride secretion from intact human intestinal mucosa.

    Directory of Open Access Journals (Sweden)

    Lucantonio Debellis

    Full Text Available BACKGROUND: The pathogenicity of the Vibrio cholerae strains belonging to serogroup O1 and O139 is due to the production of virulence factors such as cholera toxin (CT and the toxin-coregulated pilus (TCP. The remaining serogroups, which mostly lack CT and TCP, are more frequently isolated from aquatic environmental sources than from clinical samples; nevertheless, these strains have been reported to cause human disease, such as sporadic outbreaks of watery diarrhoea and inflammatory enterocolitis. This evidence suggested the possibility that other virulence factor(s than cholera toxin might be crucial in the pathogenesis of Vibrio cholerae-induced diarrhoea, but their nature remains unknown. VCC, the hemolysin produced by virtually all Vibrio cholerae strains, has been proposed as a possible candidate, though a clear-cut demonstration attesting VCC as crucial in the pathogenesis of Vibrio cholerae-induced diarrhoea is still lacking. METHODOLOGY/PRINCIPAL FINDINGS: Electrophysiological parameters and paracellular permeability of stripped human healthy colon tissues, obtained at subtotal colectomy, mounted in Ussing chamber were studied in the presence or absence of VCC purified from culture supernatants of V. cholerae O1 El Tor strain. Short circuit current (I(SC and transepithelial resistance (R(T were measured by a computerized voltage clamp system. The exposure of sigmoid colon specimens to 1 nM VCC resulted in an increase of I(SC by 20.7%, with respect to the basal values, while R(T was reduced by 12.3%. Moreover, increase in I(SC was abolished by bilateral Cl(- reduction. CONCLUSION/SIGNIFICANCE: Our results demonstrate that VCC, by forming anion channels on the apical membrane of enterocytes, triggers an outward transcellular flux of chloride. Such an ion movement, associated with the outward movement of Na(+ and water, might be responsible for the diarrhoea caused by the non-toxigenic strains of Vibrio cholerae.

  4. Prevalence and antimicrobial resistance of Vibrio spp. in retail shrimps in Vietnam.

    Science.gov (United States)

    Tra, Vu Thi Thu; Meng, Lu; Pichpol, Duangporn; Pham, Ngan Hong; Baumann, Maximilian; Alter, Thomas; Huehn, Stephan

    2016-01-01

    The aim of the study was to investigate the prevalence and the antimicrobial resistance patterns of Vibrio (V.) spp. isolated from retail shrimp in Hanoi, Vietnam A total of 202 shrimp samples were collected from retail markets located in ten urban districts of Hanoi. Among those, 201 (99.5%) samples were positive for Vibrio spp. The most common species detected was V parahaemolyticus (96.5%), followed by V. alginolyticus (56.4%), V. cholerae (2%) and V. vulnificus (1.5%). Multiple Vibrio spp. were found in 114 (56.4%) samples. None of the V. parahaemolyticus isolates carried the virulence-associated tdh (thermostable direct haemolysin) and trh (tdh-related haemolysin) genes. In total, 195 V. parahaemolyticus isolates, four V. cholerae isolates and three V. vulnificus isolates were tested for resistance to eight antimicrobial agents. V. parahaemolyticus isolates showed high rates of resistance against ampicillin (87.2%), while a moderate rate was observed for sulfamethoxazole/trimethoprim (18.5%) and intermediate resistance towards tetracycline (24.6%). Low resistance rates (0.5%) were recorded against both ciprofloxacin and cefalothin. Only one V. cholerae isolate with resistance to ampicillin and two V. cholerae isolates with resistance to sulfamethoxazole/trimethoprim were found. All V. vulnificus isolates were susceptible to the eight antimicrobial agents tested. However, the number of V. vulnificus and V. cholerae was small. Multi-resistant isolates were found in V. parahaemolyticus with a low frequency (16.9%). The results of this study revealed the ubiquitous nature of Vibrio spp. in shrimp at retail. To reduce the potential risk of Vibrio infections due to handling or consumption of undercooked seafood, good manufacturing practice as well as safe handling and processing should be encouraged. PMID:26904896

  5. Vibrio harveyi Nitroreductase Is Also a Chromate Reductase

    Science.gov (United States)

    Kwak, Young Hak; Lee, Dong Seok; Kim, Han Bok

    2003-01-01

    The chromate reductase purified from Pseudomonas ambigua was found to be homologous with several nitroreductases. Escherichia coli DH5α and Vibrio harveyi KCTC 2720 nitroreductases were chosen for the present study, and their chromate-reducing activities were determined. A fusion between glutathione S-transferase (GST) and E. coli DH5α NfsA (GST-EcNfsA), a fusion between GST and E. coli DH5α NfsB (GST-EcNfsB), and a fusion between GST and V. harveyi KCTC 2720 NfsA (GST-VhNfsA) were prepared for their overproduction and easy purification. GST-EcNfsA, GST-EcNFsB, and GST-VhNFsA efficiently reduced nitrofurazone and 2,4,6-trinitrotoluene (TNT) as their nitro substrates. The Km values for GST-EcNfsA, GST-EcNfsB, and GST-VhNfsA for chromate reduction were 11.8, 23.5, and 5.4 μM, respectively. The Vmax values for GST-EcNfsA, GST-EcNfsB, and GST-VhNfsA were 3.8, 3.9, and 10.7 nmol/min/mg of protein, respectively. GST-VhNfsA was the most effective of the three chromate reductases, as determined by each Vmax/Km value. The optimal temperatures of GST-EcNfsA, GST-EcNfsB, and GST-VhNfsA for chromate reduction were 55, 30, and 30°C, respectively. Thus, it is confirmed that nitroreductase can also act as a chromate reductase. Nitroreductases may be used in chromate remediation. GST-EcNfsA, GST-EcNfsB, and GST-VhNfsA have a molecular mass of 50 kDa and exist as a monomer in solution. Thin-layer chromatography showed that GST-EcNfsA, GST-EcNfsB, and GST-VhNfsA contain FMN as a cofactor. GST-VhNfsA reduced Cr(VI) to Cr(III). Cr(III) was much less toxic to E. coli than Cr(VI). PMID:12902220

  6. Salt-inducible promoter derivable from a lactic acid bacterium, and its use in a lactic acid bacterium for production of a desired protein

    NARCIS (Netherlands)

    Sanders, Jan Willem; Kok, Jan; Venema, Gerard; Ledeboer, Adrianus Marinus

    1998-01-01

    The invention provides a salt-inducible promoter present in SEQ ID NO: 10 and derivable from a lactic acid bacterium in isolation from the coding sequence normally controlled by said promoter in a wild-type lactic acid bacterium, with modifications and important parts thereof. Also provided are a re

  7. Investigating the decay rates of Escherichia coli relative to Vibrio parahemolyticus and Salmonella Typhi in tropical coastal waters.

    Science.gov (United States)

    Lee, Choon Weng; Ng, Angie Yee Fang; Bong, Chui Wei; Narayanan, Kumaran; Sim, Edmund Ui Hang; Ng, Ching Ching

    2011-02-01

    Using the size fractionation method, we measured the decay rates of Escherichia coli, Salmonella Typhi and Vibrio parahaemolyticus in the coastal waters of Peninsular Malaysia. The size fractions were total or unfiltered, 0.7 μm) than in the smaller fraction (<0.7 μm) suggesting the more important role played by protists. E. coli and Salmonella also decreased in the <0.02 μm fraction and suggested that these non-halophilic bacteria did not survive well in seawater. In contrast, Vibrio grew well in seawater. There was usually an increase in Vibrio after one day incubation. Our results confirmed that decay or loss rates of E. coli did not match that of Vibrio, and also did not correlate with Salmonella decay rates. However E. coli showed persistence where its decay rates were generally lower than Salmonella. PMID:21146847

  8. Evaluation of the natural prevalence of Vibrio spp. in Uruguayan mussels (Mytilus sp.) and their control using irradiation

    International Nuclear Information System (INIS)

    The presence of potentially pathogenic bacteria belonging to the Vibrionacea, especially Vibrio cholerae, and of Salmonella spp., was examined in fresh Uruguayan mussels (Mytilus sp.) during two annual seasons. The radiation decimal reduction dose (D10) of various toxigenic strains of Vibrio cholerae was determined to vary in vitro between 0.11 and 0.19 kGy. These results and those from the examination of natural Vibrio spp. contamination in mussels were used to conclude that 1.0 kGy would be enough to render Uruguayan mussels Vibrio-safe. Mussels irradiated in the shell at the optical dose survived long enough to allow the eventual introduction of irradiation as an effective intervention measure without affecting local marketing practices, and making it possible to market the fresh mussels live, as required by Uruguayan legislation. (author)

  9. A fast and indirect fluorescent antibody assay for the vibrio in large yellow croaker Pseudosciaena crocea (Richardson)

    Science.gov (United States)

    Wang, Jun; Su, Yongquan; Yan, Qingpi

    2003-03-01

    A fast and indirect fluorescent antibody assay for the Vibrio alginolyticus and V. parahaemolyticus infecting the large yellow croaker has been developed. The specific antisera for the two strains of vibrio were prepared with New Zealand rabbit and the antiserum and cross-reactive efficacy was tested by coagulation in tube. It showed that the goat anti-rabbit IgG had been labeled by fluorescence isothiocyanate (FITC). The results showed that positive reactions were 100% for the large yellow croaker Pseudosciaena crocea with typical symptom of vibrio infection, while the positive reaction to the pathogen in healthy yellow croakers reached 40%, but seemed negative for aquaculture water. The results demonstrated that this fast and indirect fluorescent antibody assay can be used not only to test the vibrio pathogen in diseased yellow croaker but also in infected animals with no symptom.

  10. Daya Hambat Ekstrak Daun Pegagan (Centella asiatica yang Diambil di Batusangkar terhadap Pertumbuhan Kuman Vibrio cholerae secara In Vitro

    Directory of Open Access Journals (Sweden)

    Nelvita Sari Ramadhan

    2015-01-01

    Full Text Available AbstrakPegagan (Centella asiatica merupakan salah satu tanaman yang digunakan sebagai obat. Salah satu manfaat yang bisa didapatkan dari pegagan (Centella asiatica adalah antibakterinya. Manfaat antibakterinya didapatkan karena pegagan (Centella asiatica mengandung zat antibakteri, diantaranya adalah saponin, tannin, alkaloid, dan flavonoid. Telah dilakukan penelitian tentang daya hambat ekstrak pegagan (Centella asiatica terhadap pertumbuhan Vibrio cholerae secara in vitro, dengan tujuan untuk mengetahui daya hambat ekstrak pegagan (Centella asiatica terhadap pertumbuhan Vibrio cholera secara in vitro. Penelitian dilakukan dengan metode eksperimental laboratorium dengan metode difusi (cakram, pada berbagai konsentrasi yaitu 5%, 10%, 20%, 30%, 40%, 50%, dan100%, di Laboratorium Mikrobiologi Fakultas Kedokteran Universitas Andalas. Hasil penelitian didapatkan bahwa ekstrak daun pegagan (Centella asiatica yang diambil di daerah Batusangkar, ternyata tidak dapat menghambat pertumbuhan kuman Vibrio cholerae secara in vitro, sedangkan tetrasiklin yang digunakan sebagai kontrol positif memberikan daya hambat yang baik terhadap pertumbuhan Vibrio cholera, dengan zona hambat 16,3 mm. Ada atau tidaknya daya hambat ekstrak pegagan (Centella asiatica terhadap pertumbuhan Vibrio cholerae dalam penelitian ini bisa dipengaruhi oleh jenis bakteri yang digunakan, metode pembuatan ekstrak yang dipakai, dan sumber daun pegagan yang digunakan dalam penelitian.Kata kunci: efek antibakteri, ekstrak daun pegagan (Centella asiatica, Vibrio choleraeAbstractCentella asiatica is one of the plants used as medicine. One of the benefits that can be obtained from Centella asiatica is an antibacterial effect. Antibacterial effect obtained as Centella asiatica contains anti-bacterial substances, such as saponins, tannins, alkaloids, and flavonoids. This study was conducted to determine the inhibition of extracts of Centella asiatica on the growth of Vibrio cholerae in vitro

  11. 发光费氏弧菌对常用色素的生物毒性评价%Application of luminescent Vibrio fischeri to evaluation of toxicity of several common pigments

    Institute of Scientific and Technical Information of China (English)

    郭柔杉; 李翔; 潘力

    2013-01-01

    A method built on the basis of the toxicity effect of pigments on luminescent bacterium Vibrio fisheri was developed for determining the toxicity and content of pigments. Results showed that there was a positive correlation between inhibitory rate of pigments against luminescent intensity of Vibrio fisheri and pigments concentration in aqueous solution,with a correlation coefficient ranging within 0.8760~0.9873. EC50 range was 0.72~2.86mg/L Inhibitory rate of pigments against luminescent intensity of Vibrio fisheri was also positively correlated with positive concentration in fruit juice,and the correlation coefficient was between 0.9136 and 0.9951. EC50 range was 1.02~2.96mg/L This showed that the toxicity of tartrazine was lower and the toxicity of amaranth was larger. Fruit juice played a role of mitigating the toxicity of the synthetic pigments. The bioluminescence inhibition rate by the pigments in the fruit juice increased with the rate significantly was higher than in aqueous solution. The study provided the initial reference for the acute toxicity testing of the food.%在探寻出色素与费氏弧菌发光抑制率存在相关性的基础上,初步建立起评价色素生物毒性的方法,并将其应用于果汁中色素产生的综合毒性的检验.结果:色素溶液质量浓度与发光抑制率呈正相关,相关系数在0.8760~0.9873之间,EC50范围在0.72~2.86mg/L之间;果汁中色素质量浓度与发光抑制率同样呈正相关,相关系数在0.9136~0.9951之间,FC50值在1.02~2.96mg/L之间.柠檬黄毒性较小,苋菜红毒性较大.果汁对人工合成色素的生物毒性具有一定影响.色素在果汁中对费氏弧菌发光抑制率随浓度增加而上升的幅度明显大于在水溶液中.本研究为食品急性生物毒性监测的研究提供初步参考.

  12. Typing and Antibiogram of Vibrio cholerae Isolates from a Tertiary Care Hospital in Pune: A 3 Year Study

    OpenAIRE

    Palewar, Meghna S; Choure, Archana C; Swati Mudshingkar; Vaishali Dohe; Anju Kagal; Renu Bhardwaj; Abhishek Jaiswal; Banwarilal Sarkar

    2015-01-01

    A retrospective analysis was done over a period of 3 years (January 2010- December 2012) in a tertiary care hospital, Pune, to note the changes in the prevalence and distribution of biotypes, serotypes, antibiotic susceptibility pattern and phage types of Vibrio cholerae isolates from clinical samples so as to be vigilant and curtail major outbreak in future. Vibrio cholerae isolates were obtained from 4.4% of the 1126 fecal specimens processed from cases of acute watery diarrhea. Majority of...

  13. Investigate the frequency of virulence genes Vibrio parahaemolyticus isolated from fish, lobsters and crabs caught from Persian Gulf

    OpenAIRE

    Farhad Safarpourdehkordi; Sahar Hosseini; Ebrahim Rahimi; Manouchehr Momeni; Emad Yahaghi; Ebrahim Khodaverdi Darian

    2014-01-01

    Background and Aim: Annually, many reports of occurrence of food poisoning due to the consumption of sea-foods contaminated with Vibrio species have been published. The present study was carried out to study the prevalence rate of Vibrio parahaemolyticus and V. cholera and evaluation of presence of virulence genes of V. parahaemolyticus in sea-food products caught from Persian Gulf. Materials and Methods: In total, 200 samples of fish, lobster and crab caught from Persian Gulf collected in...

  14. Aislamiento de Vibrio sp. a partir de órganos internos de Dormitator latifrons (Richarson, 1844 silvestres – Reporte preliminar

    Directory of Open Access Journals (Sweden)

    Raúl Mendoza-Rodríguez

    2006-09-01

    Full Text Available Se informa el hallazgo de Vibrio sp.utilizando medio de cultivo selectivoTCBS de muestras de tracto intestinal deejemplares de “monengue” Dormitatorlatifrons silvestres, especie que sealimenta principalmente de detritus enambientes inundados de zonas costeras.This report it shows the finding results ofVibrio sp. using selective culture TCBSfrom intestine samples of fishes “Pacificfat sleepers” Dormitator latifronssavages, species that is fed mainly ondetritus in flooded environments ofcoastal zones.

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

    OpenAIRE

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

    2008-01-01

    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 sensi...

  16. Exoproteome and secretome derived broad spectrum novel drug and vaccine candidates in Vibrio cholerae targeted by Piper betel derived compounds.

    Directory of Open Access Journals (Sweden)

    Debmalya Barh

    Full Text Available Vibrio cholerae is the causal organism of the cholera epidemic, which is mostly prevalent in developing and underdeveloped countries. However, incidences of cholera in developed countries are also alarming. Because of the emergence of new drug-resistant strains, even though several generic drugs and vaccines have been developed over time, Vibrio infections remain a global health problem that appeals for the development of novel drugs and vaccines against the pathogen. Here, applying comparative proteomic and reverse vaccinology approaches to the exoproteome and secretome of the pathogen, we have identified three candidate targets (ompU, uppP and yajC for most of the pathogenic Vibrio strains. Two targets (uppP and yajC are novel to Vibrio, and two targets (uppP and ompU can be used to develop both drugs and vaccines (dual targets against broad spectrum Vibrio serotypes. Using our novel computational approach, we have identified three peptide vaccine candidates that have high potential to induce both B- and T-cell-mediated immune responses from our identified two dual targets. These two targets were modeled and subjected to virtual screening against natural compounds derived from Piper betel. Seven compounds were identified first time from Piper betel to be highly effective to render the function of these targets to identify them as emerging potential drugs against Vibrio. Our preliminary validation suggests that these identified peptide vaccines and betel compounds are highly effective against Vibrio cholerae. Currently we are exhaustively validating these targets, candidate peptide vaccines, and betel derived lead compounds against a number of Vibrio species.

  17. Capsular polysaccharide-protein conjugate vaccines of carbotype 1 Vibrio vulnificus: construction, immunogenicity, and protective efficacy in a murine model.

    OpenAIRE

    Devi, S J; Hayat, U; Frasch, C E; Kreger, A S; Morris, J G

    1995-01-01

    Vibrio vulnificus causes septicemia and wound infections in immunocompromised humans. The capsular polysaccharide of Vibrio vulnificus (VvPS) is critical for virulence. We synthesized conjugate vaccines of carbotype 1 VvPS under conditions and in formulations suitable for human use. Purified VvPS was conjugated to tetanus toxoid (TT) or to inactivated V. vulnificus cytolysin or elastase by two different schemes. All conjugates elicited elevated anticapsular immunoglobulin G (IgG) and IgM and ...

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

    OpenAIRE

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

    2008-01-01

    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 sen...

  19. Vibrio cholerae expresses cell surface antigens during intestinal infection which are not expressed during in vitro culture.

    OpenAIRE

    Jonson, G.; Svennerholm, A M; Holmgren, J

    1989-01-01

    Vibrio cholerae O1 bacteria harvested directly from ligated or nonligated intestines of rabbits with experimental cholera expressed at least 7 to 8 novel, in vivo-specific cell envelope (env) proteins that were not found on vibrios after in vitro culture in various ordinary liquid media. At the same time, several of the env proteins ordinarily expressed in vitro had disappeared or become much reduced. The infection-induced novel env protein were immunogenic. In immunoblot analyses, antisera r...

  20. Free living and plankton-associated vibrios: assessment in ballast water, harbor areas and coastal ecosystems in Brazil

    Directory of Open Access Journals (Sweden)

    Irma Nelly G. Rivera

    2013-01-01

    Full Text Available Ballast water is a major transport vector of exotic aquatic species and pathogenic microorganisms. The wide-ranging spread of toxigenic Vibrio cholerae O1 from harbor areas has been frequently ascribed to discharge of contaminated ballast water into eutrophic coastal environments, such as during the onset of the seventh cholera pandemic in South America in the early 1990s. To determine the microbiological hazards of ballast waters transported to Brazilian ports, we evaluated water and plankton samples taken from (i ballast water tanks of recently arrived ships, (ii port areas along the Brazilian coastline from ~1 to 32 oS and (iii three coastal areas in São Paulo State. Vibrio concentration and toxigenic V. cholerae O1 occurrence were analyzed. Plankton-associated vibrios were more abundant than free-living vibrios in all studied environments. Vibrio cholerae was found in 9.5% of ballast tanks and 24.2% of port samples, both as free-living and attached forms, and was absent off São Paulo State. Toxigenic V. cholerae O1 isolates (ctxA+, tcpA+, involved in cholera disease, were found in ballast water (2% and harbor (2% samples. These results confirm that ballast water is an important carrier of pathogenic organisms, and that monitoring of vibrios and other plankton-attached bacteria is of paramount importance in ballast water management programs.

  1. Prevalence and Distribution of Vibrio spp. in Wild Aquatic Birds of the Southern Caribbean Sea, Venezuela, 2011-12.

    Science.gov (United States)

    Fernández-Delgado, Milagro; Sanz, Virginia; Giner, Sandra; Suárez, Paula; Contreras, Monica; Michelangeli, Fabian; García-Amado

    2016-07-01

    Vibrio spp. are associated with waterbirds mainly in temperate latitudes. We evaluated the prevalence and distribution of Vibrio spp. from fecal samples of resident and migratory aquatic birds collected during October 2011 and March 2012 at two coastal sites in the tropical southern Caribbean Sea. We amplified DNA by PCR in 40% of samples, resulting in 47% and 36% estimated prevalence for resident and migratory birds in Cuare Wildlife Refuge, and 33% and 44% in Margarita Island, respectively. We found nontoxigenic Vibrio cholerae in Cuare Wildlife Refuge with a higher prevalence in resident birds (18%). Our PCR results for Vibrio and V. cholerae were not significantly different between sites or bird migratory status. The 16S rRNA phylogenetic analysis sequences from fecal samples from Cuare Wildlife Refuge were highly similar to V. cholerae and Vibrio vulnificus , whereas sequences from Margarita Island samples formed clusters with species related to the Harveyi clade. Our findings indicate that several species of Vibrio are common in aquatic birds along the southern Caribbean Sea and contribute to our understanding of the role of birds as possible reservoirs of potentially pathogenic bacteria. PMID:27224211

  2. Transcriptome Analysis and Discovery of Genes Involved in Immune Pathways from Coelomocytes of Sea Cucumber (Apostichopus japonicus) after Vibrio splendidus Challenge

    OpenAIRE

    Qiong Gao; Meijie Liao; Yingeng Wang; Bin Li,; Zheng Zhang; Xiaojun Rong; Guiping Chen; Lan Wang

    2015-01-01

    Vibrio splendidus is identified as one of the major pathogenic factors for the skin ulceration syndrome in sea cucumber (Apostichopus japonicus), which has vastly limited the development of the sea cucumber culture industry. In order to screen the immune genes involving Vibrio splendidus challenge in sea cucumber and explore the molecular mechanism of this process, the related transcriptome and gene expression profiling of resistant and susceptible biotypes of sea cucumber with Vibrio splendi...

  3. Genetic diversity and population structure of Vibrio choierae in Colombia Diversidad genética y estructura de la población de Vibrio choierae en Colombia

    Directory of Open Access Journals (Sweden)

    Agudelo Carlos

    2003-06-01

    Full Text Available Pulsed field gel electrophoresis (PFGE was used to study thirty-four Vibrio choierae isolates from the Colombian cholera epidemic between 1991 and 1996. Three Vchoierae isolates not belonging to the epidemic in Colombia and a Vfluvialis isolate were also analysed. The genetic diversity observed for the 38 isolates typified was 0.95, a very similar valué to that obtained by Multilocus Enzyme Electrophoresis (MLEE. No cor reía tion was observed be­tween the variables characterising these isolates (serotype, origin [clinical or environmental], state, electrophoretic type (MLEE and restriction macro-fragment profile or pulsetype (PFGE. No evidence of linkage disequilibrium was obtained on evaluating this population with PFGE and MLEE genetic markers. It is suggested that the Vibrio choierae population in Colombia presents a sexual genetic structure. The lack of evidence for linkage disequilibrium and the absence of correlation between the epidemiological, biochemical and molecular variables available sustains such a hypothesis. It is also sustained by the high valué for genetic diversity obtained which could be reflecting the coexistence of several lines of descent having a high genetic flow amongst them. Key words: Vibrio choierae; Pulsed-Field Gel Electrophoresis; molecular epidemiology; population genetics; linkage disequilibrium.Se realizó la electroforesis en gel por campo pulsado (PFGE de los macrofragmentos de restricción de 34 aislamien­tos de Vibrio choierae pertenecientes a la epidemia de cólera que se presentó en Colombia entre 1991 y 1996, adicionalmente se analizaron 3 aislamientos de V. choierae no pertenecientes a esta epidemia y un aislamiento de V fluvialis. La diversidad genética observada para los 38 aislamientos tipificados fue de 0,95 valor muy similar al obtenido por Electroforesis de Enzimas Multilocus (MLEE. No se observó correlación entre las variables que carac­terizan a estos aislamientos (serotipo, origen

  4. Crystal structure of HutZ, a heme storage protein from Vibrio cholerae: A structural mismatch observed in the region of high sequence conservation

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    Liu Xiuhua

    2012-09-01

    Full Text Available Abstract Background HutZ is the sole heme storage protein identified in the pathogenic bacterium Vibrio cholerae and is required for optimal heme utilization. However, no heme oxygenase activity has been observed with this protein. Thus far, HutZ’s structure and heme-binding mechanism are unknown. Results We report the first crystal structure of HutZ in a homodimer determined at 2.0 Å resolution. The HutZ structure adopted a typical split-barrel fold. Through a docking study and site-directed mutagenesis, a heme-binding model for the HutZ dimer is proposed. Very interestingly, structural superimposition of HutZ and its homologous protein HugZ, a heme oxygenase from Helicobacter pylori, exhibited a structural mismatch of one amino acid residue in β6 of HutZ, although residues involved in this region are highly conserved in both proteins. Derived homologous models of different single point variants with model evaluations suggested that Pro140 of HutZ, corresponding to Phe215 of HugZ, might have been the main contributor to the structural mismatch. This mismatch initiates more divergent structural characteristics towards their C-terminal regions, which are essential features for the heme-binding of HugZ as a heme oxygenase. Conclusions HutZ’s deficiency in heme oxygenase activity might derive from its residue shift relative to the heme oxygenase HugZ. This residue shift also emphasized a limitation of the traditional template selection criterion for homology modeling.

  5. Cloning, purification, crystallization and preliminary X-ray analysis of two low-molecular-weight protein tyrosine phosphatases from Vibrio cholerae

    International Nuclear Information System (INIS)

    Two protein tyrosine phosphatases, namely VcLMWPTP-1 and VcLMWPTP-2, from V. cholerae have been cloned, expressed, purified and crystallized. Low-molecular-weight protein tyrosine phosphatases (LMWPTPs) are small cytoplasmic enzymes of molecular weight ∼18 kDa that belong to the large family of protein tyrosine phosphatases (PTPs). Despite their wide distribution in both prokaryotes and eukaryotes, their exact biological role in bacterial systems is not yet clear. Two low-molecular-weight protein tyrosine phosphatases (VcLMWPTP-1 and VcLMWPTP-2) from the Gram-negative bacterium Vibrio cholerae have been cloned, overexpressed, purified by Ni2+–NTA affinity chromatography followed by gel filtration and used for crystallization. Crystals of VcLMWPTP-1 were grown in the presence of ammonium sulfate and glycerol and diffracted to a resolution of 1.6 Å. VcLMWPTP-2 crystals were grown in PEG 4000 and diffracted to a resolution of 2.7 Å. Analysis of the diffraction data showed that the VcLMWPTP-1 crystals had symmetry consistent with space group P31 and that the VcLMWPTP-2 crystals had the symmetry of space group C2. Assuming the presence of four molecules in the asymmetric unit, the Matthews coefficient for the VcLMWPTP-1 crystals was estimated to be 1.97 Å3 Da−1, corresponding to a solvent content of 37.4%. The corresponding values for the VcLMWPTP-2 crystals, assuming the presence of two molecules in the asymmetric unit, were 2.77 Å3 Da−1 and 55.62%, respectively

  6. Research Progress and Perspectives of Nitrogen Fixing Bacterium, Gluconacetobacter diazotrophicus, in Monocot Plants

    Directory of Open Access Journals (Sweden)

    N. Eskin

    2014-01-01

    Full Text Available Gluconacetobacter diazotrophicus is a nitrogen fixing bacterium originally found in monocotyledon sugarcane plants in which the bacterium actively fixes atmosphere nitrogen and provides significant amounts of nitrogen to plants. This bacterium mainly colonizes intercellular spaces within the roots and stems of plants and does not require the formation of the complex root organ like nodule. The bacterium is less plant/crop specific and indeed G. diazotrophicus has been found in a number of unrelated plant species. Importantly, as the bacterium was of monocot plant origin, there exists a possibility that the nitrogen fixation feature of the bacterium may be used in many other monocot crops. This paper reviews and updates the research progress of G. diazotrophicus for the past 25 years but focuses on the recent research development.

  7. VanT, a Homologue of Vibrio harveyi LuxR, Regulates Serine, Metalloprotease, Pigment, and Biofilm Production in Vibrio anguillarum

    Science.gov (United States)

    Croxatto, Antony; Chalker, Victoria J.; Lauritz, Johan; Jass, Jana; Hardman, Andrea; Williams, Paul; Cámara, Miguel; Milton, Debra L.

    2002-01-01

    Vibrio anguillarum possesses at least two N-acylhomoserine lactone (AHL) quorum-sensing circuits, one of which is related to the luxMN system of Vibrio harveyi. In this study, we have cloned an additional gene of this circuit, vanT, encoding a V. harveyi LuxR-like transcriptional regulator. A V. anguillarum ΔvanT null mutation resulted in a significant decrease in total protease activity due to loss of expression of the metalloprotease EmpA, but no changes in either AHL production or virulence. Additional genes positively regulated by VanT were identified from a plasmid-based gene library fused to a promoterless lacZ. Three lacZ fusions (serA::lacZ, hpdA-hgdA::lacZ, and sat-vps73::lacZ) were identified which exhibited decreased expression in the ΔvanT strain. SerA is similar to 3-phosphoglycerate dehydrogenases and catalyzes the first step in the serine-glycine biosynthesis pathway. HgdA has identity with homogentisate dioxygenases, and HpdA is homologous to 4-hydroxyphenylpyruvate dioxygenases (HPPDs) involved in pigment production. V. anguillarum strains require an active VanT to produce high levels of an l-tyrosine-induced brown color via HPPD, suggesting that VanT controls pigment production. Vps73 and Sat are related to Vibrio cholerae proteins encoded within a DNA locus required for biofilm formation. A V. anguillarum ΔvanT mutant and a mutant carrying a polar mutation in the sat-vps73 DNA locus were shown to produce defective biofilms. Hence, a new member of the V. harveyi LuxR transcriptional activator family has been characterized in V. anguillarum that positively regulates serine, metalloprotease, pigment, and biofilm production. PMID:11872713

  8. Species Richness and Spatial Distribution of Pathogenic Vibrio (Bacteria, Vibrionaceae in Tropical Surface Waters: Yaoundé Metropolis Case (Cameroon, Central Africa

    Directory of Open Access Journals (Sweden)

    Tamatcho Kweyang Blandine Pulchérie

    2012-09-01

    Full Text Available In the present study, six species of Vibrio that are potential human pathogens have been isolated from surface water resources in an urban environment and have been identified. The variation of some physico-chemical factors known to have significant effects on bacterial growth and spread are also considered. The latter include: electrical conductivity, pH, total suspended solids, temperature, dissolved oxygen and carbon dioxide, and rate of water flow. All investigations were conducted according to standard methods. Application of classical bacteriological techniques led to the identification of six species of the genus. Vibrio cholera, Vibrio fluvialis, Vibrio mimicus, Vibrio alginolyticus, Vibrio parahaemolyticus and Vibrio vulnificus. Vibrio cholerae was isolated in all water sampling points, with the highest frequency 79% upstream the Mfoundi River at Etoa-Meki. Rates of isolation of Vibrio mimicus increased with increased O2 (p<0.05. Identification of these potential pathogens is a serious public health hazard highlighting the needs for resource management.

  9. Phosphate enhances levan production in the endophytic bacterium Gluconacetobacter diazotrophicus Pal5

    OpenAIRE

    Idogawa, Nao; Amamoto, Ryuta; Murata, Kousaku; Kawai, Shigeyuki

    2014-01-01

    Gluconacetobacter diazotrophicus is a gram-negative and endophytic nitrogen-fixing bacterium that has several beneficial effects in host plants; thus, utilization of this bacterium as a biofertilizer in agriculture may be possible. G. diazotrophicus synthesizes levan, a D-fructofuranosyl polymer with β-(2→6) linkages, as an exopolysaccharide and the synthesized levan improves the stress tolerance of the bacterium. In this study, we found that phosphate enhances levan production by G. diazotro...

  10. A Plant Growth-Promoting Bacterium That Decreases Nickel Toxicity in Seedlings

    OpenAIRE

    Burd, Genrich I.; Dixon, D. George; Glick, Bernard R.

    1998-01-01

    A plant growth-promoting bacterium, Kluyvera ascorbata SUD165, that contained high levels of heavy metals was isolated from soil collected near Sudbury, Ontario, Canada. The bacterium was resistant to the toxic effects of Ni2+, Pb2+, Zn2+, and CrO4−, produced a siderophore(s), and displayed 1-aminocyclopropane-1-carboxylic acid deaminase activity. Canola seeds inoculated with this bacterium and then grown under gnotobiotic conditions in the presence of high concentrations of nickel chloride w...

  11. Magnetic guidance of the magnetotactic bacterium Magnetospirillum gryphiswaldense.

    Science.gov (United States)

    Loehr, Johannes; Pfeiffer, Daniel; Schüler, Dirk; Fischer, Thomas M

    2016-04-21

    Magnetospirillum gryphiswaldense is a magnetotactic bacterium with a permanent magnetic moment capable of swimming using two bipolarly located flagella. In their natural environment these bacteria swim along the field lines of the homogeneous geomagnetic field in a typical run and reversal pattern and thereby create non-differentiable trajectories with sharp edges. In the current work we nevertheless achieve stable guidance along curved lines of mechanical instability by using a heterogeneous magnetic field of a garnet film. The successful guidance of the bacteria depends on the right balance between motility and the magnetic moment of the magnetosome chain. PMID:26972517

  12. Intracellular iron minerals in a dissimilatory iron-reducing bacterium.

    Science.gov (United States)

    Glasauer, Susan; Langley, Sean; Beveridge, Terry J

    2002-01-01

    Among prokaryotes, there are few examples of controlled mineral formation; the formation of crystalline iron oxides and sulfides [magnetite (Fe3O4) or greigite (Fe3S4)] by magnetotactic bacteria is an exception. Shewanella putrefaciens CN32, a Gram-negative, facultative anaerobic bacterium that is capable of dissimilatory iron reduction, produced microscopic intracellular grains of iron oxide minerals during growth on two-line ferrihydrite in a hydrogen-argon atmosphere. The minerals, formed at iron concentrations found in the soil and sedimentary environments where these bacteria are active, could represent an unexplored pathway for the cycling of iron by bacteria. PMID:11778045

  13. Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2004-02-24

    The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

  14. Tropical Atlantic marine macroalgae with bioactivity against virulent and antibiotic resistant Vibrio

    Directory of Open Access Journals (Sweden)

    Giselle Cristina Silva

    2013-03-01

    Full Text Available The antibacterial activity of ethanol, methanol, hexane and acetone-based extracts of the macroalgae Padina gymnospora (PG, Hypnea musciformes (HM, Ulva fasciata (UF and Caulerpa prolifera (CP was investigated. The disk diffusion method was used to evaluate the algae antimicrobial effect against standard strains of Vibrio parahaemolyticus, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella enterica and five virulent antibiotic-resistant strains of V. brasiliensis, V. xuii and V. navarrensis (isolated from the hemolymph of Litopenaeus vannamei. Ethanol extracts of PG and HM inhibited all Vibrio strains. E. coli and P. aeruginosa were only susceptible to ethanol extracts of PG. Among the methanol extracts, only UF was bioactive, inhibiting V. navarrensis. The observed inhibitory effect of ethanol extracts of PG, HM and UF against virulent antibiotic-resistant bacteria suggests these macroalgal species constitute a potential source of bioactive compounds.

  15. Involvement of penaeidins in defense reactions of the shrimp Litopenaeus stylirostris to a pathogenic vibrio.

    Science.gov (United States)

    Munoz, M; Vandenbulcke, F; Garnier, J; Gueguen, Y; Bulet, P; Saulnier, D; Bachère, E

    2004-04-01

    The present study reports for the first time the involvement of an antimicrobial peptide in the defense reactions of a shrimp infected by a pathogenic Vibrio, Vibrio penaeicida. New members of the penaeidin family were characterized in the shrimp Litopenaeus stylirostris by RT-PCR and RACE-PCR from hemocyte total RNAs, and by mass spectrometry detection and immunolocalization of mature peptides in shrimp hemocytes. In infected shrimps, bacteria and penaeidin distribution colocalized in the gills and the lymphoid organ that represented the main infected sites. Moreover, the shrimp immune response to infection involved massive hemocyte recruitment to infection sites where released penaeidin may participate in the isolation and elimination of the bacteria, We show that the ability of the shrimps to circumvent shrimp infections is closely related to a recovery phase based on the hematopoietic process. PMID:15095016

  16. DETECTION OF VIRULENCE GENES IN ENVIRONMENTAL STRAINS OF Vibrio cholerae FROM ESTUARIES IN NORTHEASTERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Francisca Gleire Rodrigues de Menezes

    2014-09-01

    Full Text Available The objectives of this study were to detect the presence of Vibrio cholerae in tropical estuaries (Northeastern Brazil and to search for virulence factors in the environmental isolates. Water and sediment samples were inoculated onto a vibrio-selective medium (TCBS, and colonies with morphological resemblance to V. cholerae were isolated. The cultures were identified phenotypically using a dichotomous key based on biochemical characteristics. The total DNA extracted was amplified by PCR to detect ompW and by multiplex PCR to detect the virulence genes ctx, tcp, zot and rfbO1. The results of the phenotypic and genotypic identification were compared. Nine strains of V. cholerae were identified phenotypically, five of which were confirmed by detection of the species-specific gene ompW. The dichotomous key was efficient at differentiating environmental strains of V. cholerae. Strains of V. cholerae were found in all four estuaries, but none possessed virulence genes.

  17. Prevalence and diversity of Aeromonas and Vibrio spp. in coastal waters of Southern Italy

    DEFF Research Database (Denmark)

    Dumontet, S.; Krovacek, K.; Svenson, S.B.; Pasquale, V.; Baloda, Suraj B.; Figliuolo, G.

    2000-01-01

    coliforms) do not always satisfactorily reflect the hygienic quality of water. The presence of Vibrionaceae on copepods was also investigated. Copepods were sampled at a station located inside the harbour of the city of Naples and were found contaminated by V. cholerae non-Ol, V. alginolyticus, V. fluvialis......A survey was undertaken to examine sea water and sediment for the presence of Vibrio and Aeromonas spp. along approximately 900 km of coast in Southern Italy during early and late summer. A quantitative analysis was also done to evaluate the water fecal contamination at the stations examined. The...... results indicate that all the investigated areas were submitted to a wide spatial fluctuation of fecal contamination and that Vibrio and Aeromonas spp. were present in both high and low fecal-contaminated stations. Sixty two percent of the investigated samples were positive for Aeromonas spp., while 42...

  18. Gene cloning and prokaryotic expression of recombinant flagellin A from Vibrio parahaemolyticus

    Science.gov (United States)

    Yuan, Ye; Wang, Xiuli; Guo, Sheping; Liu, Yang; Ge, Hui; Qiu, Xuemei

    2010-11-01

    The Gram-negative Vibrio parahaemolyticus is a common pathogen in humans and marine animals. Bacteria flagellins play an important role during infection and induction of the host immune response. Thus, flagellin proteins are an ideal target for vaccines. We amplified the complete flagellin subunit gene ( flaA) from V. parahaemolyticus ATCC 17802. We then cloned and expressed the gene into Escherichia coli BL21 (DE3) cells. The gene coded for a protein that was 62.78 kDa. We purified and characterized the protein using Ni-NTA affinity chromatography and Anti-His antibody Western blotting, respectively. Our results provide a basis for further studies into the utility of the FlaA protein as a vaccine candidate against infection by Vibrio parahaemolyticus. In addition, the purified FlaA protein can be used for further functional and structural studies.

  19. Engineered bacterial communication prevents Vibrio cholerae virulence in an infant mouse model

    OpenAIRE

    Duan, Faping; March, John C.

    2010-01-01

    To investigate the possibility of using commensal bacteria as signal mediators for inhibiting the disease cholera, we stably transformed Escherichia coli Nissle 1917 (Nissle) to express the autoinducer molecule cholera autoinducer 1 (CAI-1) (shown previously to prevent virulence when present with another signaling molecule, autoinducer 2, at high concentrations) and determined the effect on Vibrio cholerae virulence gene expression and colonization in an infant mouse model. We found that pret...

  20. Vibrio Zinc-Metalloprotease Causes Photoinactivation of Coral Endosymbionts and Coral Tissue Lesions

    OpenAIRE

    Meir Sussman; Mieog, Jos C.; Jason Doyle; Steven Victor; Willis, Bette L.; Bourne, David G.

    2009-01-01

    BACKGROUND: Coral diseases are emerging as a serious threat to coral reefs worldwide. Of nine coral infectious diseases, whose pathogens have been characterized, six are caused by agents from the family Vibrionacae, raising questions as to their origin and role in coral disease aetiology. METHODOLOGY/PRINCIPAL FINDINGS: Here we report on a Vibrio zinc-metalloprotease causing rapid photoinactivation of susceptible Symbiodinium endosymbionts followed by lesions in coral tissue. Symbiodinium pho...

  1. Berberine inhibits intestinal secretory response of Vibrio cholerae and Escherichia coli enterotoxins.

    OpenAIRE

    Sack, R B; Froehlich, J L

    1982-01-01

    Berberine, an alkaloid from the plant Berberis aristata, which has been known since ancient times as an antidiarrheal medication in India and China, inhibited by approximately 70% the secretory responses of the heat-labile enterotoxins of Vibrio cholerae and Escherichia coli in the rabbit ligated intestinal loop model. The drug was effective when given either before or after enterotoxin binding and when given either intraluminally or parenterally; it did not inhibit the stimulation of adenyla...

  2. Virulence of an emerging pathogenic lineage of Vibrio nigripulchritudo is dependent on two plasmids

    OpenAIRE

    Le Roux, Frédérique; Labreuche, Yannick; Davis, Brigid M.; Iqbal, Naeem; Mangenot, Sophie; Goarant, Cyrille; Mazel, Didier; Waldor, Matthew K.

    2011-01-01

    Summary Vibrioses are the predominant bacterial infections in marine shrimp farms. Vibrio nigripulchritudo is an emerging pathogen of the cultured shrimp Litopenaeus stylirostris in New Caledonia and other regions in the Indo-Pacific. The molecular determinants of V. nigripulchritudo pathogenicity are unknown; however, molecular epidemiological studies have revealed that recent pathogenic V. nigripulchritudo isolates from New Caledonia all cluster into a monophyletic clade and contain a small...

  3. Searching for genetic markers of virulence in Vibrio nigripulchritudo, a Litopenaeus stylirostris shrimp pathogen

    OpenAIRE

    Reynaud, Yann

    2007-01-01

    Since 1997, a new pathology seasonally occurs in new caledonian shrimp farms during the warm season. Diseased Litopenaeus stylirostris shrimp suffer from a systemic vibriosis which was attributed to highly pathogenic Vibrio nigripulchritudo. At the present time, only two farms among 17 are affected by the so called "summer syndrome". In such a context it appears urgent to develop reliable diagnostic tools to detect V. nigripulchritudo strains and to differentiate highly virulent strains from ...

  4. Molecular epidemiology of Vibrio nigripulchritudo, a pathogen of cultured penaeid shrimp (Litopenaeus stylirostris) in New Caledonia

    OpenAIRE

    Goarant, Cyrille; Reynaud, Yann; Ansquer, Dominique; De Decker, Sophie; Saulnier, Denis; Leroux, Frederique

    2006-01-01

    A collection of 57 isolates of Vibrio nigripulchritudo from either diseased or healthy shrimp and from shrimp farms environment was studied in order to gain a better understanding of the epidemiology of this pathogen, notably isolated from two distinct shrimp disease complexes. Molecular typing using two different techniques, arbitrarily primed PCR (AP-PCR) and multi-locus sequence typing (MLST), studied together with experimental pathology data allowed a relevant epidemiological insight into...

  5. Pili of a Vibrio parahaemolyticus strain as a possible colonization factor.

    OpenAIRE

    Nakasone, N; Iwanaga, M

    1990-01-01

    Pili of Vibrio parahaemolyticus were purified from a Kanagawa phenomenon-positive strain (Ha7) that belongs to serogroup O2:K3 and is adhesive to rabbit intestine. The organisms treated with the Fab fraction of antipilus antibody failed to adhere to the intestine. Purified pili had the ability to adhere to the intestine, but the pretreatment of the intestine with purified pili did not allow adherence of the organisms to the intestine. These results suggest that pili of this V. parahaemolyticu...

  6. Vibrio parahaemolyticus Strains of Pandemic Serotypes Identified from Clinical and Environmental Samples from Jiangsu, China

    OpenAIRE

    Jingjiao eLi; Feng eXue; Zhenquan eYang; Xiaoping eZhang; Dexin eZeng; Guoxiang eChao; Yuan eJiang; Baoguang eLi

    2016-01-01

    Vibrio parahaemolyticus has emerged as a major foodborne pathogen in China, Japan, Thailand and other Asian countries. In this study, 72 strains of V. parahaemolyticus were isolated from clinical and environmental samples between 2006 and 2014 in Jiangsu, China. The serotypes and six virulence genes including thermostable direct hemolysin (TDR) and TDR-related hemolysin (TRH) genes were assessed among the isolates. Twenty five serotypes were identified and O3:K6 was one of the dominant seroty...

  7. Identification of a Vibrio cholerae chemoreceptor that senses taurine and amino acids as attractants

    OpenAIRE

    So-ichiro Nishiyama; Yohei Takahashi; Kentaro Yamamoto; Daisuke Suzuki; Yasuaki Itoh; Kazumasa Sumita; Yumiko Uchida; Michio Homma; Katsumi Imada; Ikuro Kawagishi

    2016-01-01

    Vibrio cholerae, the etiological agent of cholera, was found to be attracted by taurine (2-aminoethanesulfonic acid), a major constituent of human bile. Mlp37, the closest homolog of the previously identified amino acid chemoreceptor Mlp24, was found to mediate taxis to taurine as well as L-serine, L-alanine, L-arginine, and other amino acids. Methylation of Mlp37 was enhanced upon the addition of taurine and amino acids. Isothermal titration calorimetry demonstrated that a purified periplasm...

  8. Production of Vibrio cholerae accessory cholera enterotoxin (Ace) in the yeast Pichia pastoris.

    OpenAIRE

    Trucksis, M; Conn, T L; Fasano, A; Kaper, J B

    1997-01-01

    Accessory cholera enterotoxin (Ace) is a recently identified toxin of Vibrio cholerae. Preliminary studies using crude toxin extracts in animal models indicate that Ace increases transcellular ion transport, which is proposed to contribute to diarrhea in cholera. The lack of purified toxin has hindered elucidation of the mechanism of action of Ace. In this study, ace was cloned and was expressed in and secreted by the methylotrophic yeast Pichia pastoris. Secreted toxin constituted 50% of the...

  9. The complete genome sequence of Vibrio cholerae: a tale of two chromosomes and of two lifestyles

    OpenAIRE

    Schoolnik, Gary K.; Yildiz, Fitnat H.

    2000-01-01

    Vibrio cholerae O1 has figured prominently in the history of infectious diseases as a cause of periodic global epidemics, an affliction of refugees in areas of social strife and as the disease first subjected to modern epidemiological analysis during the classic investigations of John Snow in mid-19th century London [1]. Thus, publication of the entire genome sequence of V. cholerae O1 (biotype El Tor) in Nature [2] by a consortium of investigators from The Institute for Genomic Research, the...

  10. Spongosine production by a Vibrio harveyi strain associated with the sponge Tectitethya crypta.

    Science.gov (United States)

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

    2015-03-27

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

  11. Local Vibrio Isolates Exhibit Molecular Characteristics Distinct from Reference V. harveyi and V. campbellii Strains

    Directory of Open Access Journals (Sweden)

    Hanna Cortado

    2005-06-01

    Full Text Available Six Vibrio isolates identified biochemically as Vibrio campbellii from Southeast Asian Fisheries Development Center (SEAFDEC in Tigbauan, Iloilo, were characterized by 16 rDNA sequence, total protein profile, and DNA profile analyses. Genomic DNA from the isolates were subjected to PCR using four sets of primers targeting gene fragments of hemolysin and toxR based on sequences from reference Vibrio harveyi (IFO15634, V. campbellii (IFO1563, and local isolates identified as V. harveyi. Total protein profile could not distinguish the isolates from one another and from the reference V. harveyi (IFO15634 and V. campbellii (IFO15631. Analysis of 16s rDNA sequences revealed high degree of sequence similarity (96% - 99% of the six local isolates with other Vibrio species including V. campbellii and V. parahaemolyticus, indicating that this analysis will not be useful in resolving their identity. All six isolates exhibited characteristic reference V. harveyi PCR profile when a primer set designed to amplify a 308-bp fragment of hemolysin gene in that species was used. However, no amplicons were generated for these isolates using primers that amplify toxR gene fragments in V. harveyi. This suggests that the six isolates were not bonafide V. harveyi strains. The isolates also did not exhibit V. campbellii characteristics since the primer designed to target the toxR gene in V. campbellii could not amplify DNA from any of the six isolates, suggesting that they were not bonafide V. campbellii strains either. The toxR gene from the six isolates could be amplified using a primer based on toxR gene sequences from a SEAFDEC isolate previously identified as V. harveyi (PN-9801. These data suggest that the six isolates previously identified as V. campbellii as well as PN-9801 may be classified in one group separate from bonafide reference V. harveyi and reference V. campbellii strains, based on the identical results in the molecular analyses performed in this

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

    Science.gov (United States)

    Defoirdt, Tom; Sorgeloos, Patrick

    2012-12-01

    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

  13. Factors affecting phaeomelanin production by a melanin-producing (mel) mutant of Vibrio cholerae.

    OpenAIRE

    Ivins, B E; Holmes, R K

    1981-01-01

    In a previous study we isolated melanin-producing (mel) mutants of Vibrio cholerae and demonstrated that production of melanin during growth on solid media was stimulated by L-tyrosine and L-cysteine. In the studies reported here we analyzed factors that affected melanin production in liquid media and determined the abilities of radioactively labeled amino acids to serve as precursors for the formation of melanin by V. cholerae. Radioactivity from L-cysteine and from L-tyrosine was preferenti...

  14. Vibrio parahemolyticus septicaemia in a liver transplant patient: a case report

    Directory of Open Access Journals (Sweden)

    Fairweather Morgan G

    2011-05-01

    Full Text Available Abstract Introduction Vibrio parahemolyticus is the leading cause of vibrio-associated gastroenteritis in the United States of America, usually related to poor food handling; only rarely has it been reported to cause serious infections including sepsis and soft tissue infections. In contrast, Vibrio vulnificus is a well-known cause of septicaemia, especially in patients with cirrhosis. We present a patient with V. parahemolyticus sepsis who had an orthotic liver transplant in 2007 and was on immunosuppression for chronic rejection. Clinical suspicion driven by patient presentation, travel to Gulf of Mexico and soft tissue infection resulted in early diagnosis and institution of appropriate antibiotic therapy. Case presentation A 48 year old Latin American man with a history of chronic kidney disease, orthotic liver transplant in 2007 secondary to alcoholic end stage liver disease on immunosuppressants, and chronic rejection presented to the emergency department with fever, vomiting, abdominal pain, left lower extremity swelling and fluid filled blisters after a fishing trip in the Gulf of Mexico. Samples from the blister and blood grew V. parahemolyticus. The patient was successfully treated with ceftriaxone and ciprofloxacin. Conclusion Febrile patients with underlying liver disease and/or immunosuppression should be interviewed regarding recent travel to a coastal area and seafood ingestion. If this history is obtained, appropriate empiric antibiotics must be chosen. Patients with liver disease and/or immunosuppresion should be counselled to avoid eating raw or undercooked molluscan shellfish. People can prevent Vibrio sepsis and wound infections by proper cooking of seafood and avoiding exposure of open wounds to seawater or raw shellfish products.

  15. Immunochemical Properties of the Major Outer Membrane Protein of Vibrio cholerae

    OpenAIRE

    Kabir, Shahjahan

    1983-01-01

    Antisera to the major outer membrane protein of Vibrio cholerae (molecular weight, 48,000) raised in rabbits (i) agglutinated several strains of V. cholerae and (ii) immunoprecipitated outer membrane proteins prepared from both the biotypes and serotypes of V. cholerae. Antibodies of all isotypes to the major outer membrane protein were detected in immune human sera by enzyme-linked immunosorbent assay. These results suggest that the major outer membrane protein was the common outer membrane ...

  16. Purification and characterization of pili of a Vibrio cholerae non-O1 strain.

    OpenAIRE

    Yamashiro, T.; Nakasone, N; Iwanaga, M

    1993-01-01

    Pili of the Vibrio cholerae non-O1 strain V10 were purified and characterized. The V10 pili were physicochemically and immunologically different from those of the previously reported V. cholerae non-O1 strain S7, although the pili of the two strains had homologous N-terminal amino acid sequences. V10 plus antigen was detected only in V. cholerae non-O1 strains.

  17. Molecular characteristics and antibiotic resistance of Vibrio cholerae O139 in Shandong province

    Institute of Scientific and Technical Information of China (English)

    袁玉起

    2014-01-01

    Objective To investigate the molecular epidemiological characteristics and antibiotic resistance profiles of Vibrio cholerae O139 in Shandong province.Methods A total of 13 strains of V.cholerae O139(9 clinical strains and 4 environmental strains)isolated from cholera epidemics in Shandong province since 1997 were recovered and confirmed with serum agglutination and biochemical reaction.Pulsed-field gel electrophoresis(PFGE)was carried out for molecular subtyping.Virulence genes and

  18. Phenotypic diversity of toxigenic Vibrio cholerae O1 E1 Tor strains identified in China

    Institute of Scientific and Technical Information of China (English)

    赵璇

    2014-01-01

    Objective To understand the phenotypic diversity of toxigenic Vibrio cholerae O1 E1 Tor strains isolated from different provinces in China during the last 50 years.Methods Traditional biotyping testings including susceptibility to polymyxin B,sensitivity to groupⅣphage,Voges-Proskauer test and haemolysis of sheep erythrocytes were conducted.Results Data from Biotype-specific phenotype analysis revealed that only 133 isolates carried the typical E1 Tor phenotypes while the other 251

  19. Polymerase chain reaction for detection of the cholera enterotoxin operon of Vibrio cholerae.

    OpenAIRE

    1991-01-01

    We report a set of oligonucleotide primers and amplification conditions for the polymerase chain reaction to detect the ctx operon of Vibrio cholerae. The results of this assay on strains of V. cholerae and related organisms were identical with those obtained by the DNA colony hybridization test with the polynucleotide probe. The detection limit of this system was 1 pg of chromosomal DNA or broth culture containing three viable cells. The polymerase chain reaction method could directly detect...

  20. Vibrio cholerae expresses iron-regulated outer membrane proteins in vivo.

    OpenAIRE

    Sciortino, C V; Finkelstein, R A

    1983-01-01

    A comparison was made, using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, of the outer membrane proteins of four strains of Vibrio cholerae grown in vivo in infant rabbits and in vitro in low-iron and iron-supplemented defined media. In vivo-grown V. cholerae expressed novel outer membrane-associated proteins which, in part, were similar to those observed on V. cholerae grown in vitro under conditions of iron deprivation.