Sample records for pathogen vibrio harveyi

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

    PubMed Central

    Yu, Mingjia; Ren, Chunhua; Qiu, Jinrong; Luo, Peng; Zhu, Ruyi

    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

  2. Antibacterial effect of medium-chain fatty acid: caprylic acid on gnotobiotic Artemia franciscana nauplii against shrimp pathogens Vibrio harveyi and V. parahaemolyticus

    Microsoft Academic Search

    G. Immanuel; M. Sivagnanavelmurugan; A. Palavesam

    2011-01-01

    The present study was carried out to determine the antibacterial effect of caprylic acid in the culture system of Artemia franciscana nauplii inoculated with shrimp pathogens Vibrio harveyi and V. parahaemolyticus. To begin with, the antibacterial effect of different concentrations (1, 10 and 100 mM) of caprylic acid against V. harveyi and V. parahaemolyticus was assessed through bacterial growth study. This

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

    E-print Network

    Rattanama, Pimonsri

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

  4. Evaluation of the vaccine potential of a cytotoxic protease and a protective immunogen from a pathogenic Vibrio harveyi strain.

    PubMed

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

    2010-01-22

    Vibrio harveyi is an important aquaculture pathogen that can infect a number of fish species and marine invertebrates. A putative protease, Vhp1, was identified from a pathogenic V. harveyi strain isolated from diseased fish as a protein with secretion capacity. Vhp1 is 530 amino acids in length and shares high sequence identities with several extracellular serine proteases of the Vibrio species. In silico analysis identified a protease domain in Vhp1, which is preceded by a subtilisin-N domain and followed by a bacterial pre-peptidase C-terminal domain. Purified recombinant protein corresponding to the protease domain of Vhp1 exhibited apparent proteolytic activity that was relatively heat-stable and reached maximum at pH 8.0 and 50 degrees C. The activity of purified recombinant Vhp1 protease was enhanced by Ca(2+) and inhibited by Mn(2+) and ethylenedinitrilotetraacetic acid. Cytotoxicity analyses indicated that recombinant Vhp1 protease was toxic to cultured Japanese flounder cells and could cause complete cell lysis. Immunoprotective analysis using Japanese flounder as an animal model showed that purified recombinant Vhp1 in the form of a denatured and proteolytically inactive protein was an effective subunit vaccine. To improve the vaccine potential of Vhp1, an Escherichia coli strain that expresses and secrets a cytotoxically impaired Vhp1 was constructed, which, when used as a live vaccine, afforded a high level of protection upon the vaccinated fish against lethal V. harveyi challenge. Taken together, these results demonstrate that Vhp1 is a cytotoxic protease and an effective vaccine candidate against V. harveyi infection. PMID:19897068

  5. Quorum sensing negatively regulates chitinase in Vibrio harveyi.

    PubMed

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

    2010-02-01

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

  6. Cloning and Expression of Vibrio harveyi OmpK* and GAPDH* Genes and Their Potential Application as Vaccines in Large Yellow Croakers Pseudosciaena crocea

    Microsoft Academic Search

    Chongwen Zhang; Lian Yu; Ronghua Qian

    2008-01-01

    Vibrio harveyi is a causative agent of vibriosis in the large yellow croaker Pseudosciaena crocea and causes severe losses to the aquaculture industry in China. The vaccines based on the outer membrane proteins (OMPs) of the pathogens are considered to be the optimum intervention for this disease. In this study, two V. harveyi OMP genes, OmpK* and glyceraldehyde-3-phosphate dehydrogenase (GAPDH*),

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

    PubMed

    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

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

    PubMed

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

    2015-08-01

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

  9. Autoinducers Act as Biological Timers in Vibrio harveyi

    PubMed Central

    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

  10. Vibrio Bacterin and Carboxymethyl ?-1,3-Glucans Protect Penaeus monodon from Vibrio harveyi Infection

    Microsoft Academic Search

    Supattra Somapa Klannukarn; Kanokpan Wongprasert; Kornnika Khanobdee; Prasert Meeratana; Pattira Taweepreda; Boonsirm Withyachumnarnkul

    2004-01-01

    The aims of this study were to determine the effects of Vibrio bacterin, with or without carboxymethyl ?-1,3-glucans (CMBG), on the protection of black tiger shrimp Penaeus monodon against V. harveyi infection, and to determine the mechanisms underlying the protection. The study was done with two groups of shrimp, one in short-term treatments in concrete tanks and the other in

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

    PubMed

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

    2015-01-01

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

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

    PubMed

    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

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

    Microsoft Academic Search

    Komsil Pholdaeng; Sunanta Pongsamart

    2010-01-01

    Oral administration of polysaccharide gel (PG) in shrimp diets revealed immunostimulating potential and disease resistance in Penaeus monodon (black tiger shrimp). PG from the fruit-rind of Durio zibethinus has been characterized to be a pectic polysaccharide with immunomodulating and antibacterial activities. PG inhibited growth of the shrimp bacterial pathogen, Vibrio harveyi 1526, by agar diffusion and broth microdilution tests. Clear

  14. Chitoporin from Vibrio harveyi, a Channel with Exceptional Sugar Specificity

    PubMed Central

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

    2013-01-01

    Chitoporin (VhChiP) is a sugar-specific channel responsible for the transport of chitooligosaccharides through the outer membrane of the marine bacterium Vibrio harveyi. Single channel reconstitution into black lipid membrane allowed single chitosugar binding events in the channel to be resolved. VhChiP has an exceptionally high substrate affinity, with a binding constant of K = 5.0 × 106 m?1 for its best substrate (chitohexaose). The on-rates of chitosugars depend on applied voltages, as well as the side of the sugar addition, clearly indicating the inherent asymmetry of the VhChiP lumen. The binding affinity of VhChiP for chitohexaose is 1–5 orders of magnitude larger than that of other known sugar-specific porins for their preferred substrates. Thus, VhChiP is the most potent sugar-specific channel reported to date, with its high efficiency presumably reflecting the need for the bacterium to take up chitin-containing nutrients promptly under turbulent aquatic conditions to exploit them efficiently as its sole source of energy. PMID:23447539

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

    SciTech Connect

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

    2011-05-15

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

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

    PubMed Central

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

    2004-01-01

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

  17. Solanum nigrum enhancement of the immune response and disease resistance of tiger shrimp, Penaeus monodon against Vibrio harveyi

    Microsoft Academic Search

    Ramasamy Harikrishnan; Chellam Balasundaram; Sundaram Jawahar; Moon-Soo Heo

    2011-01-01

    The effects of different doses of Solanum nigrum extract enriched diets, on the immune response and disease resistance of tiger shrimp, Penaeus monodon against Vibrio harveyi, were examined. Total hemocyte count (THC) and hyaline cell (HC) of P. monodon fed with 0.1% and 1.0% doses of S. nigrum extract enriched diets significantly increased to the control against V. harveyi whereas

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

    PubMed

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

    2014-08-01

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

  19. VanT, a Homologue of Vibrio harveyi LuxR, Regulates Serine, Metalloprotease, Pigment, and Biofilm Production in Vibrio anguillarum

    Microsoft Academic Search

    Antony Croxatto; Victoria J. Chalker; Johan Lauritz; Jana Jass; Andrea Hardman; Paul Williams; M. Camara; Debra L. Milton

    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 vanT null mutation resulted in a significant decrease in total protease activity due to

  20. Novel ?-N-acetylglucosaminidases from Vibrio harveyi 650: Cloning, expression, enzymatic properties, and subsite identification

    Microsoft Academic Search

    Wipa Suginta; Duangkamon Chuenark; Mamiko Mizuhara; Tamo Fukamizo

    2010-01-01

    BACKGROUND: Since chitin is a highly abundant natural biopolymer, many attempts have been made to convert this insoluble polysaccharide into commercially valuable products using chitinases and ?-N-acetylglucosaminidases (GlcNAcases). We have previously reported the structure and function of chitinase A from Vibrio harveyi 650. This study t reports the identification of two GlcNAcases from the same organism and their detailed functional

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

    PubMed Central

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

    2013-01-01

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

  2. Two prophenoloxidases are important for the survival of Vibrio harveyi challenged shrimp Penaeus monodon.

    PubMed

    Amparyup, Piti; Charoensapsri, Walaiporn; Tassanakajon, Anchalee

    2009-02-01

    Phenoloxidase (PO) plays an important role in arthropod melanization. Previously, a prophenoloxidase (PmproPO1) gene was cloned and characterized from the hemocytes of the black tiger shrimp, Penaeus monodon. In the present study, we report a novel proPO gene (PmproPO2) belonging to the proPO family identified from the P. monodon EST database (http://pmonodon.biotec.or.th). The full-length sequence of PmproPO2 consists of 2513bp encoding a predicted 689 amino acid residues with a calculated molecular mass and pI of 79.21kDa and 6.69, respectively. It is predicted to possess all the expected features of proPO members, including two putative tyrosinase copper-binding motifs with six histidine residues and a thiol ester-like motif, sharing 67% amino acid sequence identity with PmproPO1. Tissue distribution analyses revealed that the two proPO genes are primarily expressed in the hemocyte. Gene silencing of either PmproPO1 or PmproPO2 or both by RNA interference (RNAi) resulted in a significant decrease in the respective endogenous proPO mRNA level in hemocytes and a reduction of total PO enzyme activity by 75, 73 and 88%, respectively. Experimental infection of P. monodon with the pathogenic bacterium, Vibrio harveyi, revealed that PmproPO silenced shrimps were more susceptible to bacterial infection than the control GFP injected shrimps, and suggesting that the two proPOs are important components in the shrimp immune defense. PMID:18834900

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

    Microsoft Academic Search

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

    2008-01-01

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

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

    PubMed Central

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

    2012-01-01

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

  5. Regulation of expression of Na + -translocating NADH:quinone oxidoreductase genes in Vibrio harveyi and Klebsiella pneumoniae

    Microsoft Academic Search

    Maria S. Fadeeva; Evgenia A. Yakovtseva; Galina A. Belevich; Yulia V. Bertsova; Alexander V. Bogachev

    2007-01-01

    The expression of genes encoding sodium-translocating NADH:quinone oxidoreductase (Na+-NQR) was studied in the marine bacterium Vibrio harveyi and in the enterobacterium Klebsiella pneumoniae. It has been shown that such parameters as NaCl concentration, pH value, and presence of an uncoupler in the growth media\\u000a do not influence significantly the level of nqr expression. However, nqr expression depends on the growth

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

    PubMed

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

    2015-05-26

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

  7. Elevated cytokine responses to Vibrio harveyi infection in the Japanese pufferfish (Takifugu rubripes) treated with Lactobacillus paracasei spp. paracasei (06TCa22) isolated from the Mongolian dairy product.

    PubMed

    Biswas, G; Korenaga, H; Nagamine, R; Kawahara, S; Takeda, S; Kikuchi, Y; Dashnyam, B; Yoshida, T; Kono, T; Sakai, M

    2013-09-01

    With the aim of evaluating the effect of a Mongolian dairy product derived Lactobacillus paracasei spp. paracasei (strain 06TCa22) (Lpp) on the cytokine-mediated immune responses to Vibrio harveyi infection, we examined 16 cytokine expressions in the Japanese pufferfish, Takifugu rubripes. Fish were orally treated with the heat-killed Lpp at 1 mg g(-1) body weight d(-1) for 3 days. At 24 h posttreatment, fish were infected by an intramuscular injection of 0.1 mL V. harveyi bacterial suspension (10(8) cfu mL(-1)). Additionally, superoxide anion production (SAP) and phagocytic activity (PA) of head kidney cells were assessed during 120 h postinfection period. Significant up-regulation of pro-inflammatory (IL-1?, IL-6, IL-17A/F-3, TNF-? and TNF-N), cell-mediated immune inducing (IL-12p35, IL-12p40 and IL-18), antiviral/intra-cellular pathogen killing (I-IFN-1 and IFN-?), anti-inflammatory (IL-10) and lymphocyte agonistic (IL-2, IL-7, IL-15, IL-21 and TGF-?1) cytokines was observed in the treated fish compared to control ones during the pathogen infection. Furthermore, significantly increased SAP and PA (P < 0.01; 0.05) were recorded in the treated fish compared to untreated fish. These results suggest the beneficial role of Lpp in enhancement of cytokine-mediated immunity in the Japanese pufferfish against V. harveyi infection and application of this product as a potential fish immunostimulant. PMID:23769874

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

    PubMed

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

    2010-01-01

    In this study, we used real-time PCR to simultaneously monitor the responses of 12 key genes of the shrimp innate immune system in Litopenaeus vannamei after challenge with Vibrio harveyi. In the proPO activating system, we found that proPO was up-regulated (3.3x control at 36hpi). The hemolymph clotting genes transglutaminase (TGase) and clotting protein were also up-regulated, as were 5 genes in the antimicrobial peptide system (ALF, Crustin, Lyz, PEN2 and PEN4), with only PEN3 showing no significant changes. In the antioxidant defense system, SOD was slightly elevated while GPx was substantially down-regulated. In the pattern recognition receptor system, at 24hpi, the Toll gene (LvToll) showed the highest relative increase in expression level of all the investigated genes (15x greater than the sterile seawater control). In the second part of this study, when LvToll was knocked down by RNAi silencing, there was no effect on either survival rates or bacterial number in unchallenged shrimp. There was also no difference in mortality rates between control shrimp and LvToll-silenced shrimp when these two groups were challenged with a viral pathogen (white spot syndrome virus; WSSV). However, when LvToll-silenced shrimp were challenged by V. harveyi, there was a significant increase in mortality and bacterial CFU counts. We note that the increase in bacterial CFU count occurred even though treatment with EGFP dsRNA had the opposite effect of reducing the CFU counts. We conclude that LvToll is an important factor in the shrimp innate immune response to acute V. harveyi infection, but not to WSSV. PMID:19698743

  9. Genomics of Pathogenic Vibrio Species

    NASA Astrophysics Data System (ADS)

    Dziejman, Michelle; Yildiz, Fitnat H.

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

  10. Evaluation of RAPD-PCR and protein profile analysis to differentiate Vibrio harveyi strains prevalent along the southwest coast of India.

    PubMed

    Maiti, Biswajit; Shekar, Malathi; Khushiramani, Rekha; Karunasagar, Iddya; Karunasagar, Indrani

    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. PMID:20086292

  11. Vibrio fluvialis: an emerging human pathogen

    PubMed Central

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

    2014-01-01

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

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

    PubMed Central

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

    2012-01-01

    Assimilable organic carbon (AOC) is commonly used to measure the growth potential of microorganisms in water, but has not yet been investigated for measuring microbial growth potential in soils. In this study, a simple, rapid, and non-growth based assay to determine AOC in soil was developed using a naturally occurring luminous strain Vibrio harveyi BB721 to determine the fraction of low molecular weight organic carbon in soil water extract. Calibration of the assay was achieved by measuring the luminescence intensity of starved V. harveyi BB721 cells in the late exponential phase with a concentration range from 0 to 800 µg l?1 glucose (equivalent to 0–16.0 mg glucose C kg?1 soil) with the detection limit of 10 µg l?1 equivalent to 0.20 mg glucose C kg?1 soil. Results showed that bioluminescence was proportional to the concentration of glucose added to soil. The luminescence intensity of the cells was highly pH dependent and the optimal pH was about 7.0. The average AOC concentration in 32 soils tested was 2.9±2.2 mg glucose C kg?1. Our data showed that AOC levels in soil water extracts were significantly correlated (P<0.05) with microbial biomass determined as microbial biomass carbon, indicating that the AOC concentrations determined by the method developed might be a good indicator of soil microbial biomass. Our findings provide a new approach that may be used to determine AOC in environmental samples using a non-growth bioluminescence based assay. Understanding the levels of AOC in soil water extract provides new insights into our ability to estimate the most available carbon pool to bacteria in soil that may be easily assimilated into cells for many metabolic processes and suggest possible the links between AOC, microbial regrowth potential, and microbial biomass in soils. PMID:22679477

  13. Expression of immune-related genes in the digestive organ of shrimp, Penaeus monodon, after an oral infection by Vibrio harveyi.

    PubMed

    Soonthornchai, Wipasiri; Rungrassamee, Wanilada; Karoonuthaisiri, Nitsara; Jarayabhand, Padermsak; Klinbunga, Sirawut; Söderhäll, Kenneth; Jiravanichpaisal, Pikul

    2010-01-01

    In all previous studies, to study shrimp immune response, bacteria were directly injected into the shrimp body and as a consequence the initial step of a natural interaction was omitted. In this study we have instead used an immersion technique, which is a more natural way of establishing an infection, to study immune responses in black tiger shrimp (Penaeus monodon). Normally, Vibrio harveyi (Vh) is highly pathogenic to post-larval shrimp, but not to juveniles which usually resist an infection. In post-larvae, Vh causes a massive destruction of the digestive system, especially in the hepatopancreas and in the anterior gut. We have therefore investigated changes in transcription levels of fifteen immune-related genes and morphological changes in juvenile shrimp following an immersion of shrimp in Vh suspension. We found that a pathogenic bacterium, Vh, has the capacity to induce a local expression of some immune-related genes in shrimp after such a bacterial immersion. Our results show that in the juvenile gut small changes in expression of the antimicrobial peptide (AMP) genes such as antilipopolysaccharide factor isoform 3, crustin and penaeidin were observed. However some other genes were more strongly induced in their expression compared to the AMP genes. C-type lectin, Tachylectin 5a1 and mucin-like peritrophic membrane were increased in their expression and the C-type lectin was affected most in its expression. Several other examined genes did not change their expression levels. By performing histology studies it was found that Vh infection induced a strong perturbation of the midgut epithelium in some regions. As a consequence, the epithelial cells and basement membrane of the infected site were completely damaged and necrotic and massive hemocyte infiltration occurred underneath the affected tissue to combat the infection. PMID:19646472

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

    PubMed

    Pholdaeng, Komsil; Pongsamart, Sunanta

    2010-04-01

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

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

    PubMed

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

    2009-07-01

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

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

    Microsoft Academic Search

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

    2011-01-01

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

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

    PubMed

    González-Flecha, B; Demple, B

    1994-04-01

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

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

    PubMed Central

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

    2013-01-01

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

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

    PubMed

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

    2014-07-01

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

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

    PubMed

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

    2015-06-01

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

  1. Inhibición de vibrios patógenos de camarón por mezclas de cepas probióticas

    Microsoft Academic Search

    María Auxiliadora Sotomayor; José Luis Balcázar

    2003-01-01

    Summary Inhibition of shrimp pathogenic vibrios by mixture of probiotic strains A series of probiotic strain were challenged using an in vitro inhibition test with three pathogenic vibrios (Vibrio harveyi E22, V. vulnificus S2 and V. parahaemolyticus PA2) in order to confirm its antagonistic effect. The mixtures P63-Ili, P62-P64 and P62-P63-Ili presented a percentage of inhibition greater than 50%. This

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

    PubMed Central

    Tan, Demeng; Gram, Lone

    2014-01-01

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

  3. Expression of Vibrio harveyi acyl-ACP synthetase allows efficient entry of exogenous fatty acids into the Escherichia coli fatty acid and lipid A synthetic pathways.

    PubMed

    Jiang, Yanfang; Morgan-Kiss, Rachael M; Campbell, John W; Chan, Chi Ho; Cronan, John E

    2010-02-01

    Although the Escherichia coli fatty acid synthesis (FAS) pathway is the best studied type II fatty acid synthesis system, a major experimental limitation has been the inability to feed intermediates into the pathway in vivo because exogenously supplied free fatty acids are not efficiently converted to the acyl-acyl carrier protein (ACP) thioesters required by the pathway. We report that expression of Vibrio harveyi acyl-ACP synthetase (AasS), a soluble cytosolic enzyme that ligates free fatty acids to ACP to form acyl-ACPs, allows exogenous fatty acids to enter the E. coli fatty acid synthesis pathway. The free fatty acids are incorporated intact and can be elongated or directly incorporated into complex lipids by acyltransferases specific for acyl-ACPs. Moreover, expression of AasS strains and supplementation with the appropriate fatty acid restored growth to E. coli mutant strains that lack essential fatty acid synthesis enzymes. Thus, this strategy provides a new tool for circumventing the loss of enzymes essential for FAS function. PMID:20028080

  4. Vibrio vulnificusBiotype 2, Pathogenic for Eels, Is Also an Opportunistic Pathogen for Humans

    Microsoft Academic Search

    CARMEN AMARO; ANDELENA G. BIOSCA

    We report that the eel pathogen Vibrio vulnificus biotype 2 is also an opportunistic pathogen for humans. Results from a detailed comparative study using reference strains of both biotypes revealed that the clinical strain ATCC 33817, originally isolated from a human leg wound and classified as V. vulnificus (no reference on its biotype is noted), belongs to biotype 2 of

  5. Extracellular proteolytic enzymes produced by human pathogenic vibrio species

    PubMed Central

    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 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. PMID:24302921

  6. Vibrio harveyi NADPH-flavin oxidoreductase: cloning, sequencing and overexpression of the gene and purification and characterization of the cloned enzyme.

    PubMed Central

    Lei, B; Liu, M; Huang, S; Tu, S C

    1994-01-01

    NAD(P)H-flavin oxidoreductases (flavin reductases) from luminous bacteria catalyze the reduction of flavin by NAD(P)H and are believed to provide the reduced form of flavin mononucleotide (FMN) for luciferase in the bioluminescence reaction. By using an oligonucleotide probe based on the partial N-terminal amino acid sequence of the Vibrio harveyi NADPH-FMN oxidoreductase (flavin reductase P), a recombinant plasmid, pFRP1, was obtained which contained the frp gene encoding this enzyme. The DNA sequence of the frp gene was determined; the deduced amino acid sequence for flavin reductase P consists of 240 amino acid residues with a molecular weight of 26,312. The frp gene was overexpressed, apparently through induction, in Escherichia coli JM109 cells harboring pFRP1. The cloned flavin reductase P was purified to homogeneity by following a new and simple procedure involving FMN-agarose chromatography as a key step. The same chromatography material was also highly effective in concentrating diluted flavin reductase P. The purified enzyme is a monomer and is unusual in having a tightly bound FMN cofactor. Distinct from the free FMN, the bound FMN cofactor showed a diminished A375 peak and a slightly increased 8-nm red-shifted A453 peak and was completely or nearly nonfluorescent. The Kms for FMN and NADPH and the turnover number of this flavin reductase were determined. In comparison with other flavin reductases and homologous proteins, this flavin reductase P shows a number of distinct features with respect to primary sequence, redox center, and/or kinetic mechanism. Images PMID:8206832

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

    E-print Network

    Mekalanos, John

    ,764 mutants screened, five mutants showed reduced hemolytic activity on sheep blood agar and exhibited activity in sheep blood agar, and were 3-to 7-fold attenuated for colonization in shrimp. Comparison

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

    PubMed Central

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

    2014-01-01

    Vibrio tubiashii is reported to be a bacterial pathogen of larval Eastern oysters (Crassostrea virginica) and Pacific oysters (Crassostrea gigas) and has been associated with major hatchery crashes, causing shortages in seed oysters for commercial shellfish producers. Another bacterium, Vibrio coralliilyticus, a well-known coral pathogen, has recently been shown to elicit mortality in fish and shellfish. Several strains of V. coralliilyticus, such as ATCC 19105 and Pacific isolates RE22 and RE98, were misidentified as V. tubiashii until recently. We compared the mortalities caused by two V. tubiashii and four V. coralliilyticus strains in Eastern and Pacific oyster larvae. The 50% lethal dose (LD50) of V. coralliilyticus in Eastern oysters (defined here as the dose required to kill 50% of the population in 6 days) ranged from 1.1 × 104 to 3.0 × 104 CFU/ml seawater; strains RE98 and RE22 were the most virulent. This study shows that V. coralliilyticus causes mortality in Eastern oyster larvae. Results for Pacific oysters were similar, with LD50s between 1.2 × 104 and 4.0 × 104 CFU/ml. Vibrio tubiashii ATCC 19106 and ATCC 19109 were highly infectious toward Eastern oyster larvae but were essentially nonpathogenic toward healthy Pacific oyster larvae at dosages of ?1.1 × 104 CFU/ml. These data, coupled with the fact that several isolates originally thought to be V. tubiashii are actually V. coralliilyticus, suggest that V. coralliilyticus has been a more significant pathogen for larval bivalve shellfish than V. tubiashii, particularly on the U.S. West Coast, contributing to substantial hatchery-associated morbidity and mortality in recent years. PMID:25344234

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

    PubMed

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

    2015-01-01

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

  10. Use of gnotobiotic zebrafish to study Vibrio anguillarum pathogenicity.

    PubMed

    Oyarbide, Usua; Iturria, Iñaki; Rainieri, Sandra; Pardo, Miguel Angel

    2015-02-01

    We evaluated the use of the gnotobiotic zebrafish system to study the effects of bacterial infection, and analyzed expression of genes involved in zebrafish innate immunity. Using a GFP-labeled strain of Vibrio anguillarum, we fluorescently monitored colonization of the zebrafish intestinal tract and used gene expression analysis to compare changes in genes involved in innate immunity between nongnotobiotic and gnotobiotic larvae. The experiments performed with the gnotobiotic zebrafish reveal new insights into V. anguillarum pathogenesis. Specifically, an alteration of the host immune system was detected through the suppression of a number of innate immune genes (NFKB, IL1B, TLR4, MPX, and TRF) during the first 3 h post infection. This immunomodulation can be indicative of a "stealth mechanism" of mucus invasion in which the pathogen found a sheltered niche, a typical trait of intracellular pathogens. PMID:25548877

  11. Specific Inhibition of Chemiluminescent Activity by Pathogenic Vibrios in Hemocytes of Two Marine Bivalves

    E-print Network

    Paris-Sud XI, Université de

    1 Specific Inhibition of Chemiluminescent Activity by Pathogenic Vibrios in Hemocytes of Two Marine particles were added to the hemocytes and the chemiluminescent (CL) activity of the cells was measured over; Crassostrea gigas; bacteria; chemiluminescence; hemocytes; respiratory burst; Vibrio sp. INTRODUCTION

  12. Complete genome sequence for the shellfish pathogen Vibrio coralliilyticus RE98 isolated from a shellfish hatchery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vibrio coralliilyticus is a pathogen of corals and larval shellfish. Publications on strain RE98 list it as a Vibrio tubiashii; however, whole genome sequencing confirms RE98 as V. coralliilyticus containing a total of 6,037,824 bp consisting of two chromosomes (3,420,228 and 1,917,482 bp), and two...

  13. Characterization of a novel Vibrio pathogenicity island (VPI-2) encoding neuraminidase (nanH) among toxigenic Vibrio cholerae isolates

    Microsoft Academic Search

    William S. Jermyn; E. Fidelma Boyd

    Acquisition of virulence genes encoded on mobile genetic elements has played an important role in the emergence of pathogenic isolates of Vibrio cholerae, the causative agent of the diarrhoeal disease cholera. The genes encoding cholera toxin (ctxAB), the main cause of profuse secretory diarrhoea in cholera, are encoded on a filamentous bacteriophage CTXu. The toxin coregulated pilus (TCP), an essential

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

    SciTech Connect

    Colwell, Rita [University of Maryland] [University of Maryland

    2012-06-01

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

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

    PubMed Central

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

    2014-01-01

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

  16. Complete Genome Sequence for the Shellfish Pathogen Vibrio coralliilyticus RE98 Isolated from a Shellfish Hatchery

    PubMed Central

    Bono, James L.; Watson, Michael A.; Needleman, David S.

    2014-01-01

    Vibrio coralliilyticus is a pathogen of corals and larval shellfish. Publications on strain RE98 list it as a Vibrio tubiashii; however, whole genome sequencing confirms RE98 as V. coralliilyticus containing a total of 6,037,824 bp consisting of two chromosomes (3,420,228 and 1,917,482 bp) and two megaplasmids (380,714 and 319,400 bp). PMID:25523764

  17. Pathogenic Vibrio parahaemolyticus isolated from biofouling on commercial vessels and harbor structures.

    PubMed

    Revilla-Castellanos, Valeria J; Guerrero, Abraham; Gomez-Gil, Bruno; Navarro-Barrón, Erick; Lizárraga-Partida, Marcial L

    2015-01-01

    Ballast water is a significant vector of microbial dissemination; however, biofouling on commercial vessel hulls has been poorly studied with regard to pathogenic bacteria transport. Biofouling on three commercial vessels and seven port structures in Ensenada, Baja California, Mexico, was examined by qPCR to identify and quantify Vibrio parahaemolyticus, a worldwide recognized food-borne human pathogen. Pathogenic variants (trh+, tdh+) of V. parahaemolyticus were detected in biofouling homogenates samples from several docks in Ensenada and on the hulls of ships with Japanese and South Korean homeports, but not in reference sampling stations. A total of 26 tdh+ V. parahaemolyticus colonies and 1 ORF8+/O3:K6 strain were also isolated from enriched biofouling homogenate samples confirming the qPCR analysis. Our results suggest that biofouling is an important reservoir of pathogenic vibrios. Thus, ship biofouling might be an overlooked vector with regard to the dissemination of pathogens, primarily pathogenic V. parahaemolyticus. PMID:25921866

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

    PubMed Central

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

    1999-01-01

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

  19. Seasonal distribution of total and pathogenic Vibrio parahaemolyticus in Chesapeake Bay oysters and waters

    Microsoft Academic Search

    Salina Parveen; Kumidini A. Hettiarachchi; John C. Bowers; Jessica L. Jones; Mark L. Tamplin; Rusty McKay; William Beatty; Kathy Brohawn; Ligia V. DaSilva; Angelo DePaola

    2008-01-01

    The objectives of this study were to investigate the seasonal distribution of total and pathogenic Vibrio parahaemolyticus in the Chesapeake Bay oysters and waters, and to determine the degree of association between V. parahaemolyticus densities and selected environmental parameters. Oyster and water samples were collected monthly from three sites in Chesapeake Bay, Maryland from November 2004 through October 2005. During

  20. Cryptic luminescence in the cold-water fish pathogen Vibrio salmonicida.

    PubMed

    Fidopiastis, P M; Sørum, H; Ruby, E G

    1999-02-01

    The recent discovery that the fish pathogen Vibrio salmonicida is closely related to the luminous bacteria Vibrio fischeri and Vibrio logei suggested that V. salmonicida might also be capable of bioluminescence. Interestingly, cells of V. salmonicida were found to produce light in culture, but only when exposed to either an aliphatic aldehyde and/or the major V. fischeri autoinducer N-(3-oxo-hexanoyl)-L-homoserine lactone, a transcriptional activator of the luminescence (lux) genes. An extract of spent medium of V. salmonicida that should contain any V. salmonicida acyl-homoserine lactone autoinducer, when added to V. fischeri cells, led to an induction of their luminescence. These results show that V. salmonicida is a newly recognized luminous bacterial species that apparently both produces an autoinducer activity and responds to exogenous V. fischeri autoinducer. PMID:10201098

  1. Vibrio cincinnatiensis sp. nov., a new human pathogen.

    PubMed Central

    Brayton, P R; Bode, R B; Colwell, R R; MacDonell, M T; Hall, H L; Grimes, D J; West, P A; Bryant, T N

    1986-01-01

    A halophilic gram-negative rod was isolated from blood and cerebrospinal fluid collected from a 70-year-old male having no known contact with seafood or salt water. Positive biochemical tests included oxidase, sensitivity to 0/129, O-nitrophenyl-beta-D-galactopyranoside, lysine decarboxylase and fermentation of glucose, salicin, n-inositol, sucrose, L-mannose, L-arabinose, and arbutin. Negative tests included indole, ornithine decarboxylase, arginine dihydrolase fermentation of lactose, and production of gelatinase and urease. The DNA base composition was 45.0 mol% guanine plus cytosine. Numerical taxonomy indicated 70% similarity with known reference Vibrio sp. strains. The 5S rRNA sequence for this strain has been determined: 5'-U G C C U G G C G A C C A U A G C G U U U U G G A C C C A C C U G A U U C C A U G C C G A A C U C A G U A G U G A A A C G A A A C A G C G U C G A U G G U A G U G U G G G G U C U C C C C A U G U G A G A G U A G A A C A U C G C C A G G C A U-3'. Based on the phenetic, molecular genetic, and nucleic acid sequencing data, it is concluded that Vibrio cincinnatiensis represents a new species of the genus Vibrio sensu strictu (as defined by 5S rRNA sequencing results). On a basis of 5S rRNA comparative sequence analysis, the organism appears to share a recent common ancestor with V. gazogenes (98% homology) and close ancestry with V. mimicus, V. fluvialis, and V. metschnikovii. PMID:2422196

  2. The Phytoplankton Nannochloropsis oculata Enhances the Ability of Roseobacter Clade Bacteria to Inhibit the Growth of Fish Pathogen Vibrio anguillarum

    Microsoft Academic Search

    Emilia Noor Sharifah; Mitsuru Eguchi

    2011-01-01

    BackgroundPhytoplankton cultures are widely used in aquaculture for a variety of applications, especially as feed for fish larvae. Phytoplankton cultures are usually grown in outdoor tanks using natural seawater and contain probiotic or potentially pathogenic bacteria. Some Roseobacter clade isolates suppress growth of the fish pathogen Vibrio anguillarum. However, most published information concerns interactions between probiotic and pathogenic bacteria, and

  3. Isolation and characterization of actinomycetes antagonistic to pathogenic Vibrio spp. from nearshore marine sediments

    Microsoft Academic Search

    J. L. You; L. X. Cao; G. F. Liu; S. N. Zhou; H. M. Tan; Y. C. Lin

    2005-01-01

    Summary A total of 94 actinomycete strains were isolated from the marine sediments of a shrimp farm, 87.2% belonged to the genus Streptomyces, others were Micromonospora spp. Fifty-one percent of the actinomycete strains showed activity against the pathogenic Vibrio spp. strains. Thirty-eight percent of marine Streptomyces strains produced siderophores on chrome azurol S (CAS) agar plates. Seven strains of Streptomyces

  4. Parallel Quorum Sensing Systems Converge to Regulate Virulence in Vibrio cholerae

    Microsoft Academic Search

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

    2002-01-01

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

  5. Draft Genome Sequences of Vibrio alginolyticus Strains V1 and V2, Opportunistic Marine Pathogens.

    PubMed

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

    2015-01-01

    We announce the draft genome sequences of Vibrio alginolyticus strains V1 and V2, isolated from juvenile Sparus aurata and Dentex dentex, respectively, during outbreaks of vibriosis. The genome sequences are 5,257,950 bp with a G+C content of 44.5% for V. alginolyticus V1 and 5,068,299 bp with a G+C content of 44.8% for strain V2. These genomes provide further insights into the putative virulence factors, prophage carriage, and evolution of this opportunistic marine pathogen. PMID:26139724

  6. Draft Genome Sequences of Vibrio alginolyticus Strains V1 and V2, Opportunistic Marine Pathogens

    PubMed Central

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

    2015-01-01

    We announce the draft genome sequences of Vibrio alginolyticus strains V1 and V2, isolated from juvenile Sparus aurata and Dentex dentex, respectively, during outbreaks of vibriosis. The genome sequences are 5,257,950 bp with a G+C content of 44.5% for V. alginolyticus V1 and 5,068,299 bp with a G+C content of 44.8% for strain V2. These genomes provide further insights into the putative virulence factors, prophage carriage, and evolution of this opportunistic marine pathogen. PMID:26139724

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

    NASA Astrophysics Data System (ADS)

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

    2015-06-01

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

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

    PubMed

    Oliver, James D

    2013-05-01

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

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

    PubMed

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

    2014-02-01

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

  10. Electrochemical genosensor for specific detection of the food-borne pathogen, Vibrio cholerae.

    PubMed

    Low, Kim-Fatt; Chuenrangsikul, Kritsanaporn; Rijiravanich, Patsamon; Surareungchai, Werasak; Chan, Yean-Yean

    2012-04-01

    A disposable horseradish peroxidase (HRP)-based electrochemical genosensor was developed for chronoamperometric detection of single-stranded asymmetric lolB gene PCR amplicon (118 bp in length) of the food-borne pathogen, Vibrio cholerae. A two-step sandwich-type hybridization strategy using two specific probes was employed for specific detection of the target single-stranded DNA (ssDNA). The analytical performances of the detection platform have been evaluated using a synthetic ssDNA (ST3) which was identical to the target single-stranded amplicon and a total of 19 bacterial strains. Under optimal condition, ST3 was calibrated with a dynamic range of 0.4883-15.6250 nM. By coupling asymmetric PCR amplification, the probe-based electrochemical genosensor was highly specific to the target organism (100% specificity) and able to detect as little as 0.85 ng/?l of V. cholerae genomic DNA. PMID:22805952

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

    PubMed

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

    2012-12-13

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

  12. Taxonomy of bacterial fish pathogens

    PubMed Central

    2011-01-01

    Bacterial taxonomy has progressed from reliance on highly artificial culture-dependent techniques involving the study of phenotype (including morphological, biochemical and physiological data) to the modern applications of molecular biology, most recently 16S rRNA gene sequencing, which gives an insight into evolutionary pathways (= phylogenetics). The latter is applicable to culture-independent approaches, and has led directly to the recognition of new uncultured bacterial groups, i.e. "Candidatus", which have been associated as the cause of some fish diseases, including rainbow trout summer enteritic syndrome. One immediate benefit is that 16S rRNA gene sequencing has led to increased confidence in the accuracy of names allocated to bacterial pathogens. This is in marked contrast to the previous dominance of phenotyping, and identifications, which have been subsequently challenged in the light of 16S rRNA gene sequencing. To date, there has been some fluidity over the names of bacterial fish pathogens, with some, for example Vibrio anguillarum, being divided into two separate entities (V. anguillarum and V. ordalii). Others have been combined, for example V. carchariae, V. harveyi and V. trachuri as V. harveyi. Confusion may result with some organisms recognized by more than one name; V. anguillarum was reclassified as Beneckea and Listonella, with Vibrio and Listonella persisting in the scientific literature. Notwithstanding, modern methods have permitted real progress in the understanding of the taxonomic relationships of many bacterial fish pathogens. PMID:21314902

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

    PubMed Central

    2013-01-01

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

  14. Ocean acidification and host-pathogen interactions: blue mussels, Mytilus edulis, encountering Vibrio tubiashii.

    PubMed

    Asplund, Maria E; Baden, Susanne P; Russ, Sarah; Ellis, Robert P; Gong, Ningping; Hernroth, Bodil E

    2014-04-01

    Ocean acidification (OA) can shift the ecological balance between interacting organisms. In this study, we have used a model system to illustrate the interaction between a calcifying host organism, the blue mussel Mytilus edulis and a common bivalve bacterial pathogen, Vibrio tubiashii, with organisms being exposed to a level of acidification projected to occur by the end of the 21st century. OA exposures of the mussels were carried out in relative long-term (4 months) and short-term (4 days) experiments. We found no effect of OA on the culturability of V.?tubiashii, in broth or in seawater. OA inhibited mussel shell growth and impaired crystalline shell structures but did not appear to affect mussel immune parameters (i.e haemocyte counts and phagocytotic capacity). Despite no evident impact on host immunity or growth and virulence of the pathogen, V.?tubiashii was clearly more successful in infecting mussels exposed to long-term OA compared to those maintained under ambient conditions. Moreover, OA exposed V.?tubiashii increased their viability when exposed to haemocytes of OA-treated mussel. Our findings suggest that even though host organisms may have the capacity to cope with periods of OA, these conditions may alter the outcome of host-pathogen interactions, favouring the success of the latter. PMID:24147969

  15. Identification of the Emerging Pathogen Vibrio vulnificus Biotype 3 by Commercially Available Phenotypic Methods

    PubMed Central

    Colodner, Raul; Raz, Raul; Meir, Irit; Lazarovich, Tsilia; Lerner, Larisa; Kopelowitz, June; Keness, Yoram; Sakran, Waheeb; Ken-Dror, Shifra; Bisharat, Naiel

    2004-01-01

    Identification of the emerging pathogen Vibrio vulnificus biotype 3 has become a challenge for clinical laboratories in the last few years. In this study, the abilities of five commercial systems to identify this new species have been evaluated for the first time, using a unique collection of strains. Fifty-one well-documented wild strains of V. vulnificus biotype 3 were processed using API 20 NE, GNI+ Vitek 1 cards, ID-GNB Vitek 2 cards, Neg Combo 20 Microscan panels, and NMIC/ID-5 BD Phoenix panels. The numbers of strains identified as V. vulnificus by ID-GNB, NMIC/ID-5, and GNI+ were 50 (98.0%), 46 (90.2%), and 7 (13.7%), respectively. Neg Combo 20 Microscan panels and API 20 NE were unable to identify any of the strains of this emerging pathogen to the species level and mostly misidentifies them as other species of the Vibrionaceae family. Data on the phenotypic pattern of V. vulnificus biotype 3 when processed in all five systems as presented here could help clinical laboratories in identifying this new pathogen. PMID:15365001

  16. Molecular epidemiology and genetic variation of pathogenic Vibrio parahaemolyticus in Peru.

    PubMed

    Gavilan, Ronnie G; Zamudio, Maria L; Martinez-Urtaza, Jaime

    2013-01-01

    Vibrio parahaemolyticus is a foodborne pathogen that has become a public health concern at the global scale. The epidemiological significance of V. parahaemolyticus infections in Latin America received little attention until the winter of 1997 when cases related to the pandemic clone were detected in the region, changing the epidemic dynamics of this pathogen in Peru. With the aim to assess the impact of the arrival of the pandemic clone on local populations of pathogenic V. parahaemolyticus in Peru, we investigated the population genetics and genomic variation in a complete collection of non-pandemic strains recovered from clinical sources in Peru during the pre- and post-emergence periods of the pandemic clone. A total of 56 clinical strains isolated in Peru during the period 1994 to 2007, 13 strains from Chile and 20 strains from Asia were characterized by Multilocus Sequence Typing (MLST) and checked for the presence of Variable Genomic Regions (VGRs). The emergence of O3:K6 cases in Peru implied a drastic disruption of the seasonal dynamics of infections and a shift in the serotype dominance of pathogenic V. parahaemolyticus. After the arrival of the pandemic clone, a great diversity of serovars not previously reported was detected in the country, which supports the introduction of additional populations cohabitating with the pandemic group. Moreover, the presence of genomic regions characteristic of the pandemic clone in other non-pandemic strains may represent early evidence of genetic transfer from the introduced population to the local communities. Finally, the results of this study stress the importance of population admixture, horizontal genetic transfer and homologous recombination as major events shaping the structure and diversity of pathogenic V. parahaemolyticus. PMID:23696906

  17. Sequence polymorphism-based identification and quantification of Vibrio nigripulchritudo at the species and subspecies level targeting an emerging pathogen for cultured shrimp in New Caledonia.

    E-print Network

    Paris-Sud XI, Université de

    at the species and subspecies level targeting an emerging pathogen for cultured shrimp in New Caledonia. Cyrille-time PCR, mariculture, pathogen, Vibrio, cluster-specific, shrimp. Abstract: In a previous study, we of this molecular diagnostic tool evidenced the colonization of the shrimp pond ecosystem by the pathogenic cluster

  18. Pathogenicity of Vibrio tapetis, the etiological agent of brown ring disease in clams.

    PubMed

    Allam, Bassem; Paillard, Christine; Ford, Susan E

    2002-04-01

    Brown ring disease (BRD) causes high mortalities in the introduced Manila clam Ruditapes philippinarum cultured in western Europe. The etiological agent of BRD, Vibrio tapetis, adheres to and disrupts the production of the periostracal lamina, causing the anomalous deposition of periostracum around the inner shell. Because the primary sign of BRD is found outside the soft tissues, the processes leading to death are not as obvious as those for internal pathogens. This study was designed to evaluate the pathogenicity of V. tapetis, in an attempt to help explain the mechanisms of mortality. We found high mortalities (up to 100%) for clams following the inoculation of V. tapetis into the extrapallial space (between mantle and inner shell) or the posterior adductor muscle of healthy R. philippinarum. Microscopy and immunological detection methods showed that the pathogen was rapidly eliminated from tissues and hemolymph of animals that survived the inoculation. In clams that died, the bacteria were found to have proliferated, resulting in severe tissue disruption. Bacteria were able to penetrate into tissues from the extrapallial space through the external epithelium of the mantle. In contrast, no mortalities were observed following injection of V. tapetis in the native European clam Ruditapes decussatus, which is resistant to BRD. This clam rapidly eliminated the bacterium from hemolymph and soft tissues. Clam mortality associated with BRD in the field is likely to result from the penetration of V. tapetis into the clam's extrapallial space through the disrupted periostracal lamina and from there into the soft tissues through the irritated mantle epithelium. Some bacteria also penetrate through the digestive epithelia. In either case, bacteria proliferate rapidly in the soft tissues, causing severe damage and subsequent death. PMID:12033709

  19. Inhibition of photosynthesis and bleaching of zooxanthellae by the coral pathogen Vibrio shiloi.

    PubMed

    Ben-Haim, Y; Banim, E; Kushmaro, A; Loya, Y; Rosenberg, E

    1999-06-01

    Vibrio shiloi is the causative agent of bleaching (loss of endosymbiotic zooxanthellae) of the coral Oculina patagonica in the Mediterranean Sea. To obtain information on the mechanism of bleaching, we examined the effect of secreted material (AK1-S) produced by V. shiloi on zooxanthellae isolated from corals. AK1-S caused a rapid inhibition of photosynthesis of the algae, as measured with a Mini-PAM fluorometer. The inhibition of photosynthesis was caused by (i) ammonia produced during the growth of V. shiloi on protein-containing media and (ii) a non-dialysable heat-resistant factor. This latter material did not inhibit photosynthesis of the algae by itself but, when added to different concentrations of NH4Cl, enhanced the inhibition approximately two- to threefold. Ammonia and the enhancer were effective to different degrees on zooxanthellae isolated from four species of coral examined. In addition to the rapid inhibition of photosynthesis, AK1-S caused bleaching (loss of pigmentation) and lysis of zooxanthellae. Bleaching was more rapid than lysis, reaching a peak (25% bleached algae) after 6 h. The factors in AK1-S responsible for bleaching and lysis were different from those responsible for the inhibition of photosynthesis, because they were heat sensitive, non-dialysable and active in the dark. Thus, the coral pathogen V. shiloi produces an array of extracellular materials that can inhibit photosynthesis, bleach and lyse zooxanthellae. PMID:11207741

  20. Genomic Science in Understanding Cholera Outbreaks and Evolution of Vibrio cholerae as a Human Pathogen

    PubMed Central

    Mekalanos, John J.

    2014-01-01

    Modern genomic and bioinformatic approaches have been applied to interrogate the V. cholerae genome, the role of genomic elements in cholera disease, and the origin, relatedness, and dissemination of epidemic strains. A universal attribute of choleragenic strains includes a repertoire of pathogenicity islands and virulence genes, namely the CTX–? prophage and Toxin Co-regulated Pilus (TCP) in addition to other virulent genetic elements including those referred to as Seventh Pandemic Islands. During the last decade, the advent of Next Generation Sequencing (NGS) has provided highly resolved and often complete genomic sequences of epidemic isolates in addition to both clinical and environmental strains isolated from geographically unconnected regions. Genomic comparisons of these strains, as was completed during and following the Haitian outbreak in 2010, reveals that most epidemic strains appear closely related, regardless of region of origin. Non-O1 clinical or environmental strains may also possess some virulence islands, but phylogenic analysis of the core genome suggests they are more diverse and distantly related than those isolated during epidemics. Like Haiti, genomic studies that examine both the Vibrio core- and pan-genome in addition to Single Nucleotide Polymorphisms (SNPs) conclude that a number of epidemics are caused by strains that closely resemble those in Asia, and often appear to originate there and then spread globally. The accumulation of SNPs in the epidemic strains over time can then be applied to better understand the evolution of the V. cholerae genome as an etiological agent. PMID:24590676

  1. Identification and characterization of a zinc metalloprotease associated with invasion by the fish pathogen Vibrio anguillarum.

    PubMed Central

    Norqvist, A; Norrman, B; Wolf-Watz, H

    1990-01-01

    An invasiveness-defective mutant of the fish-pathogenic bacterium Vibrio anguillarum was isolated. Compared with the wild type, this mutant had a 1,000-fold higher 50% lethal dose after immersion infection of rainbow trout, Oncorhynchus mykiss, while after intraperitoneal infection, the mutant had only a 10-fold higher 50% lethal dose. In addition, the mutant showed a lower level of protease activity. Two forms of the protease (Pa and Pb) were found after sodium dodecyl sulfate-polyacrylamide gel electrophoresis of nonheated samples. Pa was found predominantly in protease preparations of the wild type, while Pb was the predominant form in the mutant. Conversion of Pb to Pa was observed in protease preparations after incubation at 4 degrees C. Characterization of the protease showed that it was an elastolytic enzyme which required Zn2+ for activity and Ca2+ for stability. The molecular mass of the protease was 36 kilodaltons. N-terminal amino acid sequence analysis of the protease of V. anguillarum revealed homology to the elastase of Pseudomonas aeruginosa and the protease of Legionella pneumophila. Images PMID:2228244

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

    PubMed Central

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

    2015-01-01

    Vibrio parahaemolyticus is an aquatic halophilic bacterium that occupies estuarine and coastal marine environments, and is a leading cause of seafood-borne food poisoning cases. To investigate the environmental reservoir and potential gene flow that occurs among V. parahaemolyticus isolates, the virulence-associated gene content and genome diversity of a collection of 133 V. parahaemolyticus isolates were analyzed. Phylogenetic analysis of housekeeping genes, and pulsed-field gel electrophoresis, demonstrated that there is genetic similarity among V. parahaemolyticus clinical and environmental isolates. Whole-genome sequencing and comparative analysis of six representative V. parahaemolyticus isolates was used to identify genes that are unique to the clinical and environmental isolates examined. Comparative genomics demonstrated an O3:K6 environmental isolate, AF91, which was cultured from sediment collected in Florida in 2006, has significant genomic similarity to the post-1995 O3:K6 isolates. However, AF91 lacks the majority of the virulence-associated genes and genomic islands associated with these highly virulent post-1995 O3:K6 genomes. These findings demonstrate that although they do not contain most of the known virulence-associated regions, some V. parahaemolyticus environmental isolates exhibit significant genetic similarity to clinical isolates. This highlights the dynamic nature of the V. parahaemolyticus genome allowing them to transition between aquatic and host-pathogen states. PMID:25852665

  3. Microarray-based detection of genetic heterogeneity, antimicrobial resistance, and the viable but nonculturable state in human pathogenic Vibrio spp.

    PubMed

    Vora, Gary J; Meador, Carolyn E; Bird, Michele M; Bopp, Cheryl A; Andreadis, Joanne D; Stenger, David A

    2005-12-27

    The morbidity and mortality associated with Vibrio-mediated waterborne diseases necessitates the development of sensitive detection technologies that are able to elucidate the identity, potential pathogenicity, susceptibility, and viability of contaminating bacteria in a timely manner. For this purpose, we have designed a single multiplex PCR assay to simultaneously amplify 95 diagnostic regions (encompassing species/serogroup-specific, antimicrobial resistance, and known toxin markers) and combined it with a long oligonucleotide microarray to create a platform capable of rapidly detecting and discriminating the major human pathogenic species from the genus Vibrio: V. cholerae, V. parahaemolyticus, V. vulnificus, and V. mimicus. We were able to validate this strategy by testing 100 geographically and temporally distributed isolates and observed an excellent concordance between species- and serotype-level microarray-based identification and traditional typing methods. In addition to accurate identification, the microarray simultaneously provided evidence of antibiotic resistance genes and mobile genetic elements, such as sulfamethoxazole-trimethoprim constins and class I integrons, and common toxin (ctxAB, rtxA, hap, hlyA, tl, tdh, trh, vvhA, vlly, and vmhA) and pathogenicity (tcpA, type III secretion system) genes that are associated with pathogenic Vibrio. The versatility of this method was further underscored by its ability to detect the expression of known toxin and virulence genes from potentially harmful viable but nonculturable organisms. The results suggest that this molecular identification method provides rapid and definitive information that would be of value in epidemiological, environmental, and health risk assessment surveillance. PMID:16354840

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

    PubMed Central

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

    2014-01-01

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

  5. Detection and Quantification of the Coral Pathogen Vibrio coralliilyticus by Real-Time PCR with TaqMan Fluorescent Probes ? †

    PubMed Central

    Pollock, F. Joseph; Morris, Pamela J.; Willis, Bette L.; Bourne, David G.

    2010-01-01

    A real-time quantitative PCR-based detection assay targeting the dnaJ gene (encoding heat shock protein 40) of the coral pathogen Vibrio coralliilyticus was developed. The assay is sensitive, detecting as little as 1 CFU per ml in seawater and 104 CFU per cm2 of coral tissue. Moreover, inhibition by DNA and cells derived from bacteria other than V. coralliilyticus was minimal. This assay represents a novel approach to coral disease diagnosis that will advance the field of coral disease research. PMID:20525865

  6. Characterization of two TonB systems in marine fish pathogen Vibrio alginolyticus : their roles in iron utilization and virulence

    Microsoft Academic Search

    Qiyao Wang; Qin Liu; Xiaodan Cao; Minjun Yang; Yuanxing Zhang

    2008-01-01

    In Gram-negative bacteria, the TonB\\/ExbB\\/ExbD complex is required to energize the specific high-affinity receptors mediating\\u000a iron uptake processes. In fish pathogen Vibrio alginolyticus MVP01, which exhibited capacities to scavenge iron sources with various specific iron uptake systems, we identified and characterized\\u000a two sets of TonB systems. In V. alginolyticus, TonB1 and TonB2 systems were arrayed as TonB1–ExbB1–ExbD1 and ExbB2–ExbD2–TonB2, respectively.

  7. Temporal and Spatial Variability in Culturable Pathogenic Vibrio spp. in Lake Pontchartrain, Louisiana, following Hurricanes Katrina and Rita ? †

    PubMed Central

    Nigro, Olivia D.; Hou, Aixin; Vithanage, Gayatri; Fujioka, Roger S.; Steward, Grieg F.

    2011-01-01

    We investigated the abundance, distribution, and virulence gene content of Vibrio cholerae, V. parahaemolyticus, and V. vulnificus in the waters of southern Lake Pontchartrain in Louisiana on four occasions from October 2005 to September 2006, using selective cultivation and molecular assays. The three targeted pathogenic vibrios were generally below the detection level in January 2006, when the water was cold (13°C), and most abundant in September 2006, when the lake water was warmest (30°C). The maximum values for these species were higher than reported previously for the lake by severalfold to orders of magnitude. The only variable consistently correlated with total vibrio abundance within a single sampling was distance from shore (P = 0.000). Multiple linear regression of the entire data set revealed that distance from shore, temperature, and turbidity together explained 82.1% of the variability in total vibrio CFU. The log-transformed mean abundance of V. vulnificus CFU in the lake was significantly correlated with temperature (P = 0.014), but not salinity (P = 0.625). Virulence-associated genes of V. cholerae (ctx) and V. parahaemolyticus (trh and tdh) were not detected in any isolates of these species (n = 128 and n = 20, respectively). In contrast, 16S rRNA typing of V. vulnificus (n = 298) revealed the presence of both environmental (type A) and clinical (type B) strains. The percentage of the B-type V. vulnificus was significantly higher in the lake in October 2005 (35.8% of the total) than at other sampling times (P ? 0.004), consistent with the view that these strains represent distinct ecotypes. PMID:21642406

  8. Molecular characterization of the TonB2 protein from the fish pathogen Vibrio anguillarum

    PubMed Central

    LÓPEZ, Claudia S.; PEACOCK, R. Sean; CROSA, Jorge H.; VOGEL, Hans J.

    2011-01-01

    In the fish pathogen Vibrio anguillarum the TonB2 protein is essential for the uptake of the indigenous siderophore anguibactin. Here we describe deletion mutants and alanine replacements affecting the final six amino acids of TonB2. Deletions of more than two amino acids of the TonB2 C-terminus abolished ferric-anguibactin transport, whereas replacement of the last three residues resulted in a protein with wild-type transport properties. We have solved the high-resolution solution structure of the TonB2 C-terminal domain by NMR spectroscopy. The core of this domain (residues 121–206) has an ????? structure, whereas residues 76–120 are flexible and extended. This overall folding topology is similar to the Escherichia coli TonB C-terminal domain, albeit with two differences: the ?4 strand found at the C-terminus of TonB is absent in TonB2, and loop 3 is extended by 9 Å (0.9 nm) in TonB2. By examining several mutants, we determined that a complete loop 3 is not essential for TonB2 activity. Our results indicate that the ?4 strand of E. coli TonB is not required for activity of the TonB system across Gram-negative bacterial species. We have also determined, through NMR chemical-shift-perturbation experiments, that the E. coli TonB binds in vitro to the TonB box from the TonB2-dependent outer membrane transporter FatA; moreover, it can substitute in vivo for TonB2 during ferric-anguibactin transport in V. anguillarum. Unexpectedly, TonB2 did not bind in vitro to the FatA TonB-box region, suggesting that additional factors may be required to promote this interaction. Overall our results indicate that TonB2 is a representative of a different class of TonB proteins. PMID:18973471

  9. Characterization of VPI Pathogenicity Island and CTX  Prophage in Environmental Strains of Vibrio cholerae

    Microsoft Academic Search

    ASISH K. MUKHOPADHYAY; SOUMEN CHAKRABORTY; YOSHIFUMI TAKEDA; G. BALAKRISH NAIR; DOUGLAS E. BERG

    2001-01-01

    Environmental isolates of Vibrio cholerae of eight randomly amplified polymorphic DNA (RAPD) fingerprint types from Calcutta, India, that were unusual in containing toxin-coregulated pilus or cholera toxin genes but not O1 or O139 antigens of epidemic strains were studied by PCR and sequencing to gain insights into V. cholerae evolution. We found that each isolate contained a variant form of

  10. Draft Genome Sequence of the Human-Pathogenic Bacterium Vibrio alginolyticus E0666.

    PubMed

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

    2013-01-01

    Vibrio alginolyticus is a Gram-negative halophilic bacterium with worldwide distribution. In this work, we report the draft genome sequence of a V. alginolyticus strain (E0666) isolated from Epinephelus coioides ascites in the Shantou city of Guangdong Province, China. PMID:23990586

  11. Examination of Diverse Toxin-Coregulated Pilus-Positive Vibrio cholerae Strains Fails To Demonstrate Evidence for Vibrio Pathogenicity Island Phage

    PubMed Central

    Faruque, Shah M.; Zhu, Jun; Asadulghani; Kamruzzaman, M.; Mekalanos, John J.

    2003-01-01

    The major virulence factors of toxigenic Vibrio cholerae are cholera toxin, which is encoded by a lysogenic filamentous bacteriophage (CTX?), and toxin-coregulated pilus (TCP), an essential colonization factor that is also the receptor for CTX?. The genes involved in the biosynthesis of TCP reside in a pathogenicity island, which has been reported to correspond to the genome of another filamentous phage (designated VPI?) and to encode functions necessary for the production of infectious VPI? particles. We examined 46 V. cholerae strains having diverse origins and carrying different genetic variants of the TCP island for the production of the VPI? and CTX? in different culture conditions, including induction of prophages with mitomycin C and UV irradiation. Although 9 of 10 V. cholerae O139 strains and 12 of 15 toxigenic El Tor strains tested produced extracellular CTX?, none of the 46 TCP-positive strains produced detectable VPI? in repeated assays, which detected as few as 10 particles of a control CTX phage per ml. These results contradict the previous report regarding VPI?-mediated horizontal transfer of the TCP genes and suggest that the TCP island is unable to support the production of phage particles. Further studies are necessary to understand the mechanism of horizontal transfer of the TCP island. PMID:12761075

  12. Investigation of Reservoirs of Fecal Indicator Bacteria and Water Quality on the Presence of Allochthonous Pathogens and the Ecology and Virulence of Vibrio vulnificus

    Microsoft Academic Search

    Christopher Staley

    2012-01-01

    The quality of recreational and shellfishing waters has historically been monitored using commensal, allochthonous bacteria shed in feces (fecal indicator bacteria, FIB). The fate of FIB in the environment should mimic that of bacterial, protozoan, and viral human pathogens, which may also be allochthonous (e.g. Salmonella, Cryptosporidium, or enteric viruses) or autochthonous (e.g. Vibrio spp.) to aquatic environments. FIB are

  13. The Phytoplankton Nannochloropsis oculata Enhances the Ability of Roseobacter Clade Bacteria to Inhibit the Growth of Fish Pathogen Vibrio anguillarum

    PubMed Central

    Sharifah, Emilia Noor; Eguchi, Mitsuru

    2011-01-01

    Background Phytoplankton cultures are widely used in aquaculture for a variety of applications, especially as feed for fish larvae. Phytoplankton cultures are usually grown in outdoor tanks using natural seawater and contain probiotic or potentially pathogenic bacteria. Some Roseobacter clade isolates suppress growth of the fish pathogen Vibrio anguillarum. However, most published information concerns interactions between probiotic and pathogenic bacteria, and little information is available regarding the importance of phytoplankton in these interactions. The objectives of this study, therefore, were to identify probiotic Roseobacter clade members in phytoplankton cultures used for rearing fish larvae and to investigate their inhibitory activity towards bacterial fish pathogens in the presence of the phytoplankton Nannochloropsis oculata. Methodology/Principal Findings The fish pathogen V. anguillarum, was challenged with 6 Roseobacter clade isolates (Sulfitobacter sp. (2 strains), Thalassobius sp., Stappia sp., Rhodobacter sp., and Antarctobacter sp.) from phytoplankton cultures under 3 different nutritional conditions. In an organic nutrient-rich medium (VNSS), 6 Roseobacter clade isolates, as well as V. anguillarum, grew well (109 CFU/ml), even when cocultured. In contrast, in a phytoplankton culture medium (ESM) based on artificial seawater, coculture with the 6 isolates decreased the viability of V. anguillarum by approximately more than 10-fold. Excreted substances in media conditioned by growth of the phytoplankton N. oculata (NCF medium) resulted in the complete eradication of V. anguillarum when cocultured with the roseobacters. Autoclaved NCF had the same inhibitory effect. Furthermore, Sulfitobacter sp. much more efficiently incorporated 14C- photosynthetic metabolites (14C-EPM) excreted by N. oculata than did V. anguillarum. Conclusion/Significance Cocultures of a phytoplankton species and Roseobacter clade members exhibited a greater antibacterial effect against an important fish pathogen (V. anguillarum) than roseobacters alone. Thus, cooperation of N. oculata, and perhaps other phytoplankton species, with certain roseobacters might provide a powerful tool for eliminating fish pathogens from fish-rearing tanks. PMID:22053210

  14. Selection and identification of non-pathogenic bacteria isolated from fermented pickles with antagonistic properties against two shrimp pathogens.

    PubMed

    Zokaeifar, Hadi; Balcázar, José Luis; Kamarudin, Mohd Salleh; Sijam, Kamaruzaman; Arshad, Aziz; Saad, Che Roos

    2012-06-01

    In this study, potential probiotic strains were isolated from fermented pickles based on antagonistic activity against two shrimp pathogens (Vibrio harveyi and Vibrio parahaemolyticus). Two strains L10 and G1 were identified by biochemical tests, followed by16S ribosomal RNA gene sequence analysis as Bacillus subtilis, and characterized by PCR amplification of repetitive bacterial DNA elements (Rep-PCR). Subsequently, B. subtilis L10 and G1 strains were tested for antibacterial activity under different physical conditions, including culture medium, salinity, pH and temperature using the agar well diffusion assay. Among the different culture media, LB broth was the most suitable medium for antibacterial production. Both strains showed the highest level of antibacterial activity against two pathogens at 30?°C and 1.0% NaCl. Under the pH conditions, strain G1 showed the greatest activity against V. harveyi at pH 7.3-8.0 and against V. parahaemolyticus at pH 6.0-8.0, whereas strain L10 showed the greatest activity against two pathogens at pH 7.3. The cell-free supernatants of both strains were treated with four different enzymes in order to characterize the antibacterial substances against V. harveyi. The result showed considerable reduction of antibacterial activity for both strains, indicating the proteinaceous nature of the antibacterial substances. A wide range of tolerance to NaCl, pH and temperature was also recorded for both strains. In addition, both strains showed no virulence effect in juvenile shrimp Litopenaeus vannamei. On the basis of these results and safety of strains to L. vannamei, they may be considered for future challenge experiments in shrimp as a very promising alternative to the use of antibiotics. PMID:22491136

  15. Molecular cloning of the recA analog from the marine fish pathogen Vibrio anguillarum 775

    SciTech Connect

    Singer, J.T. (Univ. of Maine, Orono (USA))

    1989-11-01

    The recA analog from Vibrio anguillarum 775 was isolated by complementation of recA mutations in Escherichia coli, and its protein product was identified. The recA analog promoted recombination between two partially deleted lactose operons, stimulated both spontaneous and mitomycin C-induced phage production in RecA- lambda lysogens, and restored near wild-type levels of resistance to UV radiation and methyl methanesulfonate.

  16. Vaccines for viral and bacterial pathogens causing acute gastroenteritis: Part I: Overview, vaccines for enteric viruses and Vibrio cholerae.

    PubMed

    O'Ryan, Miguel; Vidal, Roberto; del Canto, Felipe; Salazar, Juan Carlos; Montero, David

    2015-01-01

    Efforts to develop vaccines for prevention of acute diarrhea have been going on for more than 40 y with partial success. The myriad of pathogens, more than 20, that have been identified as a cause of acute diarrhea throughout the years pose a significant challenge for selecting and further developing the most relevant vaccine candidates. Based on pathogen distribution as identified in epidemiological studies performed mostly in low-resource countries, rotavirus, Cryptosporidium, Shigella, diarrheogenic E. coli and V. cholerae are predominant, and thus the main targets for vaccine development and implementation. Vaccination against norovirus is most relevant in middle/high-income countries and possibly in resource-deprived countries, pending a more precise characterization of disease impact. Only a few licensed vaccines are currently available, of which rotavirus vaccines have been the most outstanding in demonstrating a significant impact in a short time period. This is a comprehensive review, divided into 2 articles, of nearly 50 vaccine candidates against the most relevant viral and bacterial pathogens that cause acute gastroenteritis. In order to facilitate reading, sections for each pathogen are organized as follows: i) a discussion of the main epidemiological and pathogenic features; and ii) a discussion of vaccines based on their stage of development, moving from current licensed vaccines to vaccines in advanced stage of development (in phase IIb or III trials) to vaccines in early stages of clinical development (in phase I/II) or preclinical development in animal models. In this first article we discuss rotavirus, norovirus and Vibrio cholerae. In the following article we will discuss Shigella, Salmonella (non-typhoidal), diarrheogenic E. coli (enterotoxigenic and enterohemorragic), and Campylobacter jejuni. PMID:25715048

  17. Statistical evaluation of a quality control method for isolation of pathogenic Vibrio species on selected thiosulfate-citrate-bile salts-sucrose agars.

    PubMed Central

    West, P A; Russek, E; Brayton, P R; Colwell, R R

    1982-01-01

    The recovery of Vibrio cholerae, Vibrio fluvialis, Vibrio parahaemolyticus, and Vibrio vulnificus, employing eight strains of each species, was studied by using four brands of thiosulfate-citrate-bile salts-sucrose (TCBS) agar prepared according to manufacturers' instructions and following a standardized procedure. A standardized broth inoculum of each strain was placed on duplicate plates of each brand of TCBS agar and also on tryptic soy agar (Difco Laboratories) containing 1% (wt/vol) NaCl, the latter serving as the control. Plates were inoculated in a sequence designed to compensate for bias associated with multiplication of the bacteria during the inoculation procedure. Colony counts and quality of growth were recorded after incubation for 18 h at 35 degrees C. The comparison procedure was repeated four times at weekly intervals. Data were analyzed by using an analysis of variance model. The recovery and quality of growth of each species varied significantly on the different brands of TCBS agar. Significant variability was also identified for some components of the inoculation procedure. Modifications of the inoculation procedure are suggested to minimize sources of variance. A simplified statistical procedure, based on the t test, is described for media quality control for laboratories routinely isolating pathogenic Vibrio spp. PMID:6761362

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

    PubMed Central

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

    2014-01-01

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

  19. Occurrence and distribution of halophilic vibrios in subtropical coastal waters of Hong Kong.

    PubMed Central

    Chan, K Y; Woo, M L; Lo, K W; French, G L

    1986-01-01

    The summer occurrence and distribution of halophilic vibrios in the subtropical coastal waters of Hong Kong were investigated. The density of vibrios in six sample sites ranged from 90 to 6,700 per ml, which made up 0.41 to 40% of the total bacterial populations of these sample sites. The sucrose-positive vibrios were found to be much more common (88% of total vibrios) than the sucrose-negative ones. A total of 48 strains belonging to six Vibrio species were fully characterized. Among these, Vibrio alginolyticus was the most frequently isolated, followed by V. parahaemolyticus, V. harveyi, V. vulnificus, V. campbellii, and V. fluvialis. The finding that eight of the nine strains of V. harveyi showed a positive Kanagawa reaction warrants further study. PMID:3789725

  20. Seasonal Variation in Abundance of Total and Pathogenic Vibrio parahaemolyticus Bacteria in Oysters along the Southwest Coast of India

    PubMed Central

    Deepanjali, A.; Kumar, H. Sanath; Karunasagar, I.; Karunasagar, I.

    2005-01-01

    The seasonal abundance of Vibrio parahaemolyticus in oysters from two estuaries along the southwest coast of India was studied by colony hybridization using nonradioactive labeled oligonucleotide probes. The density of total V. parahaemolyticus bacteria was determined using a probe binding to the tlh (thermolabile hemolysin) gene, and the density of pathogenic V. parahaemolyticus bacteria was determined by using a probe binding to the tdh (thermostable direct hemolysin) gene. Furthermore, the prevalence of V. parahaemolyticus was studied by PCR amplification of the toxR, tdh, and trh genes. PCR was performed directly with oyster homogenates and also following enrichment in alkaline peptone water for 6 and 18 h. V. parahaemolyticus was detected in 93.87% of the samples, and the densities ranged from <10 to 104 organisms per g. Pathogenic V. parahaemolyticus could be detected in 5 of 49 samples (10.2%) by colony hybridization using the tdh probe and in 3 of 49 samples (6.1%) by PCR. Isolates from one of the samples belonged to the pandemic serotype O3:K6. Twenty-nine of the 49 samples analyzed (59.3%) were positive as determined by PCR for the presence of the trh gene in the enrichment broth media. trh-positive V. parahaemolyticus was frequently found in oysters from India. PMID:16000764

  1. Effect of poly-?-hydroxybutyrate on Chinese mitten crab, Eriocheir sinensis, larvae challenged with pathogenic Vibrio anguillarum.

    PubMed

    Sui, L; Cai, J; Sun, H; Wille, M; Bossier, P

    2012-05-01

    This study investigated the protective effect of poly-?-hydroxybutyrate (PHB) on Chinese mitten crab, Eriocheir sinensis, zoea larvae challenged with pathogenic Vibrio anguillarum. PHB was delivered to the crab larvae through rotifer and Artemia bioencapsulation. Zoea 3 larvae were challenged with V. anguillarum at a final concentration of 10(5) CFU mL(-1). PHB-enriched rotifers and Artemia nauplii were added to the culture water 24 h prior to, upon and 24 h after challenge. The results confirmed that PHB could enhance the survival and growth of unexposed E. sinensis larvae. Moreover, PHB protected larvae from the pathogen as the larvae fed PHB-enriched live food showed the highest survival and development rate in all challenged groups (P < 0.05). Furthermore, larval performance was the best when PHB was delivered to the larvae 24 h before challenge (P < 0.05). In conclusion, our results indicate that PHB can be used as part of an effective strategy to protect E. sinensis larvae from V. anguillarum resulting in higher survival and better growth, especially when applied before the challenge. PMID:22417317

  2. Facile synthesis of multifunctional multi-walled carbon nanotube for pathogen Vibrio alginolyticus detection in fishery and environmental samples.

    PubMed

    Liu, Yue; Hu, Jia; Sun, Jin-Sheng; Li, Yan; Xue, Shu-Xia; Chen, Xiao-Qin; Li, Xiao-Shuang; Du, Gui-Xiang

    2014-10-01

    Interest in carbon nanotubes for detecting the presence of pathogens arises because of developments in chemical vapor deposition synthesis and progresses in biomolecular modification. Here we reported the facile synthesis of multi-walled carbon nanotubes (MWCNTs), which functioned as immuno-, magnetic, fluorescent sensors in detecting Vibrio alginolyticus (Va). The structures and properties of functionalized MWCNTs were characterized by ultraviolet (UV), Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), magnetic property measurement system (MPMS) and fluorescent spectra (FL). It was found that the functionalized MWCNTs showed: (1) low nonspecific adsorption for antibody-antigen, (2) strong interaction with antibody, and (3) high immune-magnetic activity for pathogenic cells. Further investigations revealed a strong positive linear relationship (R=0.9912) between the fluorescence intensity and the concentration of Va in the range of 9.0 × 10(2) to 1.5 × 10(6) cfum L(-1). Moreover, the relative standard deviation for 11 replicate detections of 1.0 × 10(4) cfum L(-1) Va was 2.4%, and no cross-reaction with the other four strains was found, indicating a good specificity for Va detection. These results demonstrated the remarkable advantages of the multifunctional MWCNTs, which offer great potential for the rapid, sensitive and quantitative detection of Va in fishery and environmental samples. PMID:25059166

  3. Assessment of polyaromatic hydrocarbon degradation by potentially pathogenic environmental Vibrio parahaemolyticus isolates from coastal Louisiana, USA.

    PubMed

    Smith, Conor B; Johnson, Crystal N; King, Gary M

    2012-01-01

    A presumed Vibrio parahaemolyticus isolate from Chesapeake Bay, Maryland, USA was previously reported to grow on phenanthrene, a polyaromatic hydrocarbon (PAH) found in crude oil. Following the Deepwater Horizon oil spill in the Gulf of Mexico, concerns were raised that PAH-degrading V. parahaemolyticus could increase in abundance, leading to elevated risks of disease derived from shellfish consumption. To assess this possibility, we examined responses to naphthalene and phenanthrene of 17 coastal Louisiana environmental V. parahaemolyticus isolates representing five distinct genotypes. Isolates were obtained immediately after the spill began and after oil had reached the Louisiana coast. None of the isolates grew on or oxidized either substrate and a naphthalene degradation product, 1-naphthol, substantially inhibited growth of some isolates. The use of PAH by V. parahaemolyticus is unusual, and an increase in human health risks due to stimulation of V. parahaemolyticus growth by oil-derived PAH under in situ conditions appears unlikely. PMID:22063191

  4. First Characterization of Bacterial Pathogen, Vibrio alginolyticus, for Porites andrewsi White Syndrome in the South China Sea

    PubMed Central

    Chaoqun, Hu; Zhixiong, Zhu; Shifeng, Wang; Yongcan, Zhou

    2013-01-01

    Background White syndrome, a term for scleractinian coral disease with progressive tissue loss, is known to cause depressed growth and increased morality of coral reefs in the major oceans around the world, and the occurrence of this disease has been frequently reported in the past few decades. Investigations during April to September in both 2010 and 2011 identified widespread Poritesandrewsi White syndrome (PAWS) in Xisha Archipelago, South China Sea. However, the causes and etiology of PAWS have been unknown. Methodology/Principal Findings A transmission experiment was performed on P. andrewsi in the Qilianyu Subgroup (QLY). The results showed that there was a significant (P ? 0.05) difference between test and control groups after 28 days if the invalid replicates were excluded. Rates of tissue loss ranged from 0.90-10.76 cm2 d-1 with a mean of 5.40 ± 3.34 cm2 d-1 (mean ± SD). Bacterial strains were isolated from the PAWS corals at the disease outbreak sites in QLY of the Xisha Archipelago, South China Sea, and included in laboratory-based infection trials to satisfy Koch’s postulates for establishing causality. Following exposure to bacterial concentrations of 105 cells mL-1, the infected colonies exhibited similar signs to those observed in the field. Using phylogenetic 16S rRNA gene analysis, classical phenotypic trait comparison, Biolog automatic identification system, MALDI-TOF mass spectrometry and MALDI Biotyper method, two pathogenic strains were identified as Vibrioalginolyticus. Conclusion/Significance This is the first report of V. alginolyticus as a pathogenic agent of PAWS in the South China Sea. Our results point out an urgent need to develop sensitive detection methods for V. alginolyticus virulence strains and robust diagnostics for coral disease caused by this and Vibrio pathogenic bacterium in the South China Sea. PMID:24086529

  5. Temporal and Spatial Variation in the Abundance of Total and Pathogenic Vibrio parahaemolyticus in Shellfish in China.

    PubMed

    Han, Haihong; Li, Fengqin; Yan, Weixing; Guo, Yunchang; Li, Ning; Liu, Xiumei; Zhu, Jianghui; Xu, Jin; Chen, Yan; Li, Xiugui; Lv, Hong; Zhang, Yiqian; Cai, Te; Chen, Yuzhen

    2015-01-01

    We investigated the abundance of total and pathogenic Vibrio parahaemolyticus in shellfish sampled from four provinces in China during May 2013 and March 2014 using the most probable number-polymerase chain reaction (MPN-PCR) method. Total V. parahaemolyticus was detected in 67.7% of 496 samples. A total of 38.1% and 10.1% of samples exceeded 1,000 MPN g-1 and 10,000 MPN g-1, respectively. V. parahaemolyticus densities followed a seasonal and geographical trend, with Guangxi and Sichuan shellfish possessing total V. parahaemolyticus levels that were 100-fold higher than those of the Liaoning and Shandong regions. Moreover, the levels of V. parahaemolyticus were at least 10-fold higher in the summer and autumn than in the cooler seasons. Pathogenic V. parahaemolyticus levels were generally lower than total V. parahaemolyticus levels by several log units and tended to be high in samples contaminated with high total V. parahaemolyticus levels. The aqua farms had a lower prevalence but higher abundance of total V. parahaemolyticus compared to retail markets. The catering markets showed the lowest levels of total V. parahaemolyticus, but 20.0% of samples exceeded 1,000 MPN g-1. The levels of both total and pathogenic V. parahaemolyticus in oysters were higher than in clams. The log-transformed abundance of V. parahaemolyticus was significantly correlated with both water temperature and air temperature but not water salinity. These results provide baseline contamination data of V. parahaemolyticus in shellfish in China, which can be applied to local risk assessments to prioritize risk control to key sectors and evaluate the effectiveness of future control measures. PMID:26061712

  6. Temporal and Spatial Variation in the Abundance of Total and Pathogenic Vibrio parahaemolyticus in Shellfish in China

    PubMed Central

    Han, Haihong; Li, Fengqin; Yan, Weixing; Guo, Yunchang; Li, Ning; Liu, Xiumei; Zhu, Jianghui; Xu, Jin; Chen, Yan; Li, Xiugui; Lv, Hong; Zhang, Yiqian; Cai, Te; Chen, Yuzhen

    2015-01-01

    We investigated the abundance of total and pathogenic Vibrio parahaemolyticus in shellfish sampled from four provinces in China during May 2013 and March 2014 using the most probable number-polymerase chain reaction (MPN-PCR) method. Total V. parahaemolyticus was detected in 67.7% of 496 samples. A total of 38.1% and 10.1% of samples exceeded 1,000 MPN g-1 and 10,000 MPN g-1, respectively. V. parahaemolyticus densities followed a seasonal and geographical trend, with Guangxi and Sichuan shellfish possessing total V. parahaemolyticus levels that were 100-fold higher than those of the Liaoning and Shandong regions. Moreover, the levels of V. parahaemolyticus were at least 10-fold higher in the summer and autumn than in the cooler seasons. Pathogenic V. parahaemolyticus levels were generally lower than total V. parahaemolyticus levels by several log units and tended to be high in samples contaminated with high total V. parahaemolyticus levels. The aqua farms had a lower prevalence but higher abundance of total V. parahaemolyticus compared to retail markets. The catering markets showed the lowest levels of total V. parahaemolyticus, but 20.0% of samples exceeded 1,000 MPN g-1. The levels of both total and pathogenic V. parahaemolyticus in oysters were higher than in clams. The log-transformed abundance of V. parahaemolyticus was significantly correlated with both water temperature and air temperature but not water salinity. These results provide baseline contamination data of V. parahaemolyticus in shellfish in China, which can be applied to local risk assessments to prioritize risk control to key sectors and evaluate the effectiveness of future control measures. PMID:26061712

  7. Citrus Bioactive Compounds: Isolation, Characterization and Modulation of Bacterial Intercellular Communication and Pathogenicity

    E-print Network

    Vikram, Amit

    2012-07-16

    in Vibrio harveyi, Escherichia coli O157:H7 and Salmonella Typhimurium LT2. The first experiment was focused on purification of limonoids from grapefruit and sour orange seeds. The limonoids were extracted using organic solvents and purified...

  8. Polysiphonia harveyi, WNC2005-126

    NSDL National Science Digital Library

    Dr. Wilson Freshwater

    2008-03-07

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

  9. Proline-Rich Peptide from the Coral Pathogen Vibrio shiloi That Inhibits Photosynthesis of Zooxanthellae

    PubMed Central

    Banin, Ehud; Khare, Sanjay K.; Naider, Fred; Rosenberg, Eugene

    2001-01-01

    The coral-bleaching bacterium Vibrio shiloi biosynthesizes and secretes an extracellular peptide, referred to as toxin P, which inhibits photosynthesis of coral symbiotic algae (zooxanthellae). Toxin P was produced during the stationary phase when the bacterium was grown on peptone or Casamino Acids media at 29°C. Glycerol inhibited the production of toxin P. Toxin P was purified to homogeneity, yielding the following 12-residue peptide: PYPVYAPPPVVP (molecular weight, 1,295.54). The structure of toxin P was confirmed by chemical synthesis. In the presence of 12.5 mM NH4Cl, pure natural or synthetic toxin P (10 ?M) caused a 64% decrease in the photosynthetic quantum yield of zooxanthellae within 5 min. The inhibition was proportional to the toxin P concentration. Toxin P bound avidly to zooxanthellae, such that subsequent addition of NH4Cl resulted in rapid inhibition of photosynthesis. When zooxanthellae were incubated in the presence of NH4Cl and toxin P, there was a rapid decrease in the pH (pH 7.8 to 7.2) of the bulk liquid, suggesting that toxin P facilitates transport of NH3 into the cell. It is known that uptake of NH3 into cells can destroy the pH gradient and block photosynthesis. This mode of action of toxin P can help explain the mechanism of coral bleaching by V. shiloi. PMID:11282602

  10. Multidrug Efflux Pumps from Enterobacteriaceae, Vibrio cholerae and Staphylococcus aureus Bacterial Food Pathogens

    PubMed Central

    Andersen, Jody L.; He, Gui-Xin; Kakarla, Prathusha; KC, Ranjana; Kumar, Sanath; Lakra, Wazir Singh; Mukherjee, Mun Mun; Ranaweera, Indrika; Shrestha, Ugina; Tran, Thuy; Varela, Manuel F.

    2015-01-01

    Foodborne illnesses caused by bacterial microorganisms are common worldwide and constitute a serious public health concern. In particular, microorganisms belonging to the Enterobacteriaceae and Vibrionaceae families of Gram-negative bacteria, and to the Staphylococcus genus of Gram-positive bacteria are important causative agents of food poisoning and infection in the gastrointestinal tract of humans. Recently, variants of these bacteria have developed resistance to medically important chemotherapeutic agents. Multidrug resistant Escherichia coli, Salmonella enterica, Vibrio cholerae, Enterobacter spp., and Staphylococcus aureus are becoming increasingly recalcitrant to clinical treatment in human patients. Of the various bacterial resistance mechanisms against antimicrobial agents, multidrug efflux pumps comprise a major cause of multiple drug resistance. These multidrug efflux pump systems reside in the biological membrane of the bacteria and actively extrude antimicrobial agents from bacterial cells. This review article summarizes the evolution of these bacterial drug efflux pump systems from a molecular biological standpoint and provides a framework for future work aimed at reducing the conditions that foster dissemination of these multidrug resistant causative agents through human populations. PMID:25635914

  11. Multidrug efflux pumps from Enterobacteriaceae, Vibrio cholerae and Staphylococcus aureus bacterial food pathogens.

    PubMed

    Andersen, Jody L; He, Gui-Xin; Kakarla, Prathusha; K C, Ranjana; Kumar, Sanath; Lakra, Wazir Singh; Mukherjee, Mun Mun; Ranaweera, Indrika; Shrestha, Ugina; Tran, Thuy; Varela, Manuel F

    2015-02-01

    Foodborne illnesses caused by bacterial microorganisms are common worldwide and constitute a serious public health concern. In particular, microorganisms belonging to the Enterobacteriaceae and Vibrionaceae families of Gram-negative bacteria, and to the Staphylococcus genus of Gram-positive bacteria are important causative agents of food poisoning and infection in the gastrointestinal tract of humans. Recently, variants of these bacteria have developed resistance to medically important chemotherapeutic agents. Multidrug resistant Escherichia coli, Salmonella enterica, Vibrio cholerae, Enterobacter spp., and Staphylococcus aureus are becoming increasingly recalcitrant to clinical treatment in human patients. Of the various bacterial resistance mechanisms against antimicrobial agents, multidrug efflux pumps comprise a major cause of multiple drug resistance. These multidrug efflux pump systems reside in the biological membrane of the bacteria and actively extrude antimicrobial agents from bacterial cells. This review article summarizes the evolution of these bacterial drug efflux pump systems from a molecular biological standpoint and provides a framework for future work aimed at reducing the conditions that foster dissemination of these multidrug resistant causative agents through human populations. PMID:25635914

  12. Characterization of protease from Alcaligens faecalis and its antibacterial activity on fish pathogens.

    PubMed

    Annamalai, N; Kumar, Arun; Saravanakumar, A; Vijaylakshmi, S; Balasubramanian, T

    2011-11-01

    Alcaligens faecalis AU01 isolated from seafood industry effluent produced an alkaline protease. The optimum culture conditions for growth as well as enzyme production were 37 degrees C and pH 8. The partially purified protease had specific activity of 9.66 with 17.77% recovery with the molecular weight of 33 kDa and it was active between 30-70 degrees C and optimum being at 55 degrees C and pH 9. The enzyme retains more than 85% activity at 70 degrees C and 78% even at pH 10. The enzyme inhibited the growth of fish pathogens such as Flavobacterium sp., Pseudomonas fluorescens, Vibrio harveyi, Proteus sp. and Vibrio parahaemolyticus. From the present study it can be concluded that Alcaligens faecalis AU01 has the potential for aquaculture as probiotic agent and other several applications. PMID:22471216

  13. Piezoresistive microcantilever-based DNA sensor for sensitive detection of pathogenic Vibrio cholerae O1 in food sample.

    PubMed

    Khemthongcharoen, Numfon; Wonglumsom, Wijit; Suppat, Assawapong; Jaruwongrungsee, Kata; Tuantranont, Adisorn; Promptmas, Chamras

    2015-01-15

    Pathogenic Vibrio cholerae produces a cholera toxin which is the cause of a severe diarrheal disease called "Cholera". Available detection methods, including standard bacteriological test and immuno-based detection, are specific to the suspected pathogenic V. cholerae O1 and O139, but they are not specific to the cholera toxin producible strain. This work combined the polymerase chain reaction (PCR) of cholera toxin gene, ctxA gene, and microcantilever-based DNA sensor to improve the sensitivity and specificity of detection. Gold coated microcantilever, 250 µm long and 50 µm wide, with an embedded polysilicon wire acting as a piezoresistive material was modified by a self-assembled monolayer (SAM) of 3-mercaptopropionic acid (MPA) for immobilization of specific DNA probe via avidin layer on the surface. The avidin and 5' biotinylated single-stranded DNA (ssDNA) probe concentrations were optimized for the immobilization at 50 µg/mL and 1 µM, respectively. The hybridization between ssDNA probe on this DNA sensor and target DNA creates nanomechanical bending and resistance change of piezoresistive material inside the beam. This microcantilever-based DNA sensor offers a detection sensitivity of 3.25 pg or 14 nM of DNA template for ctxA gene detection. The lowest number of V. cholerae O1 in food sample with and without the enrichment process that the polymerase chain reaction (PCR) for ctxA gene combined with this DNA sensor can detect is 0.835 and 835 cells/g, respectively. This detection sensitivity is 10 times higher than that of the conventional PCR method. PMID:25113053

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

    PubMed Central

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

    2012-01-01

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

  15. Implications of Chitin Attachment for the Environmental Persistence and Clinical Nature of the Human Pathogen Vibrio vulnificus

    PubMed Central

    Williams, Tiffany C.; Ayrapetyan, Mesrop

    2014-01-01

    Vibrio vulnificus naturally inhabits a variety of aquatic organisms, including oysters, and is the leading cause of seafood-related death in the United States. Strains of this bacterium are genetically classified into environmental (E) and clinical (C) genotypes, which correlate with source of isolation. E-genotype strains integrate into marine aggregates more efficiently than do C-genotype strains, leading to a greater uptake of strains of this genotype by oysters feeding on these aggregates. The causes of this increased integration of E-type strains into marine “snow” have not been demonstrated. Here, we further investigate the physiological and genetic causalities for this genotypic heterogeneity by examining the ability of strains of each genotype to attach to chitin, a major constituent of marine snow. We found that E-genotype strains attach to chitin with significantly greater efficiency than do C-genotype strains when incubated at 20°C. Type IV pili were implicated in chitin adherence, and even in the absence of chitin, the expression level of type IV pilin genes (pilA, pilD, and mshA) was found to be inherently higher by E genotypes than by C genotypes. In contrast, the level of expression of N-acetylglucosamine binding protein A (gbpA) was significantly higher in C-genotype strains. Interestingly, incubation at a clinically relevant temperature (37°C) resulted in a significant increase in C-genotype attachment to chitin, which subsequently provided a protective effect against exposure to acid or bile, thus offering a clue into their increased incidence in human infections. This study suggests that C- and E-genotype strains have intrinsically divergent physiological programs, which may help explain the observed differences in the ecology and pathogenic potential between these two genotypes. PMID:24362430

  16. Characterization of Pathogenic Vibrio parahaemolyticus Isolates from Clinical Sources in Spain and Comparison with Asian and North American Pandemic Isolates

    PubMed Central

    Martinez-Urtaza, Jaime; Lozano-Leon, Antonio; DePaola, Angelo; Ishibashi, Masanori; Shimada, Kanae; Nishibuchi, Mitsuaki; Liebana, Ernesto

    2004-01-01

    In spite of the potential risk involved with contamination of seafood with Vibrio parahaemolyticus, there is a lack of information on the occurrence of pathogenic V. parahaemolyticus in Europe. This organism was isolated in 1999 from a large outbreak (64 cases admitted to a single hospital) associated with raw oyster consumption in Galicia, Spain, one of the most important regions in shellfish production worldwide. Two V. parahaemolyticus isolates from the 1999 Galicia outbreak, three additional clinical isolates obtained in the same period from hospitals in Spain, two reference strains from clinical sources, and five Spanish environmental isolates were examined. Seventeen isolates belonging to the pandemic clone isolated in Asia and North America were included in the study for comparison. All isolates were characterized by serotyping, PCR for virulence-related genes, pulsed-field gel electrophoresis (PFGE), and plasmid analysis. Four of the five clinical isolates from hospitals in Spain belonged to serotype O4:K11; the remaining isolate was O4:K untypeable (KUT). All five isolates were positive for V. parahaemolyticus toxR and tlh (species-specific genes) and tdh and negative for trh and group-specific PCR (a PCR method for detection of the pandemic clone). PFGE analysis with NotI and SfiI discriminated the European isolates in two closely related PFGE types included in a homogeneous cluster, clearly differentiated from the Asian and North American isolates. The five environmental isolates belonged to serotypes O2:K28, O2:KUT, O3:K53, O4:KUT, and O8:K22 and were negative for all virulence genes. The five isolates were discriminated into five different PFGE types unrelated to any other isolate included in the study. While the virulence characteristics (tdh positive, trh negative) of the Spanish clinical isolates matched those of the O3:K6 clone from Asia and North America, they were clearly excluded from this clone by group-specific PCR, PFGE, and serotyping. The results of this study suggest that a unique and specific clone could be related to the V. parahaemolyticus infections in Europe. PMID:15472326

  17. The occurrence of Vibrio species in tropical shrimp culture environments; implications for food safety

    Microsoft Academic Search

    Shubha Gopal; Subhendu K. Otta; Sanath Kumar; Indrani Karunasagar; Matsuaki Nishibuchi; Iddya Karunasagar

    2005-01-01

    The occurrence of various Vibrio species in water, sediment and shrimp samples from multiple shrimp farm environments from the east and west coast of India was studied. The relative abundance was higher in west coast farms (ca. 104 cfu\\/ml water) when compared to the east coast (ca. 102 cfu\\/ml water). Vibrio alginolyticus (3–19%), V. parahaemolyticus (2–13%), V. harveyi (1–7%) and

  18. Alterations in Hemolymph and Extrapallial Fluid Parameters in the Manila Clam, Ruditapes philippinarum, Challenged with the Pathogen Vibrio tapetis

    Microsoft Academic Search

    Bassem Allam; Christine Paillard; Michel Auffret

    2000-01-01

    In a recent study, we demonstrated the presence of defense factors, competent hemocytes and high enzymatic activities (peptidases, hydrolases, lytic, etc.), in the extrapallial fluid, located between the mantle and the shell, of the Manila clam, Ruditapes philippinarum. In Europe, this species is affected by brown ring disease, an epizootic disease caused by the bacterium Vibrio tapetis. The present work

  19. Antibiotic resistance in the shellfish pathogen Vibrio parahaemolyticus isolated from the coastal water and sediment of Georgia and South Carolina, USA.

    PubMed

    Baker-Austin, Craig; McArthur, J V; Tuckfield, R Cary; Najarro, Michael; Lindell, Angela H; Gooch, Jan; Stepanauskas, Ramunas

    2008-12-01

    Vibrio parahaemolyticus is a gram-negative pathogen commonly encountered in estuarine and marine environments, and a common cause of seafood-related gastrointestinal infections. We isolated 350 V. parahaemolyticus strains from water and sediment at three locations along the Atlantic coast of Georgia and South Carolina during various seasons. These isolates were tested for susceptibility to 24 antibiotics. Isolate virulence was determined through PCR of tdh and trh genes. The breadth of resistance to antibiotics was unexpectedly high, with 24% isolates demonstrating resistance to 10 or more agents. A significant fraction of isolates were resistant to diverse beta-lactams, aminoglycosides, and other classes of antibiotics. Fifteen of the 350 strains possessed virulence genes, with no apparent correlation between virulence and site, sample type, or season of isolation. Antibiotic resistance was slightly reduced among the virulent strains. This study represents one of the largest surveys to date of the virulence and antibiotic resistance in environmental V. parahaemolyticus strains. The observed antibiotic susceptibility patterns suggest that current guidelines for the antibiotic treatment of non-cholerae Vibrio should be reevaluated and extended. PMID:19244914

  20. Probing the protective mechanism of poly-ß-hydroxybutyrate against vibriosis by using gnotobiotic Artemia franciscana and Vibrio campbellii as host-pathogen model.

    PubMed

    Baruah, Kartik; Huy, Tran T; Norouzitallab, Parisa; Niu, Yufeng; Gupta, Sanjay K; De Schryver, Peter; Bossier, Peter

    2015-01-01

    The compound poly-ß-hydroxybutyrate (PHB), a polymer of the short chain fatty acid ß-hydroxybutyrate, was shown to protect experimental animals against a variety of bacterial diseases, (including vibriosis in farmed aquatic animals), albeit through undefined mechanisms. Here we aimed at unraveling the underlying mechanism behind the protective effect of PHB against bacterial disease using gnotobiotically-cultured brine shrimp Artemia franciscana and pathogenic Vibrio campbellii as host-pathogen model. The gnotobiotic model system is crucial for such studies because it eliminates any possible microbial interference (naturally present in any type of aquatic environment) in these mechanistic studies and furthermore facilitates the interpretation of the results in terms of a cause effect relationship. We showed clear evidences indicating that PHB conferred protection to Artemia host against V. campbellii by a mechanism of inducing heat shock protein (Hsp) 70. Additionally, our results also showed that this salutary effect of PHB was associated with the generation of protective innate immune responses, especially the prophenoloxidase and transglutaminase immune systems - phenomena possibly mediated by PHB-induced Hsp70. From overall results, we conclude that PHB induces Hsp70 and this induced Hsp70 might contribute in part to the protection of Artemia against pathogenic V. campbellii. PMID:25822312

  1. Genetic characterization of clinical and environmental Vibrio parahaemolyticus from the Northeast USA reveals emerging resident and non-indigenous pathogen lineages

    PubMed Central

    Xu, Feng; Ilyas, Saba; Hall, Jeffrey A.; Jones, Stephen H.; Cooper, Vaughn S.; Whistler, Cheryl A.

    2015-01-01

    Gastric infections caused by the environmentally transmitted pathogen, Vibrio parahaemolyticus, have increased over the last two decades, including in many parts of the United States (US). However, until recently, infections linked to shellfish from the cool northeastern US waters were rare. Cases have risen in the Northeast, consistent with changes in local V. parahaemolyticus populations toward greater abundance or a shift in constituent pathogens. We examined 94 clinical isolates from a period of increasing disease in the region and compared them to 200 environmental counterparts to identify resident and non-indigenous lineages and to gain insight into the emergence of pathogenic types. Genotyping and multi-locus sequence analysis (MLSA) of clinical isolates collected from 2010 to 2013 in Massachusetts, New Hampshire, and Maine revealed their polyphyletic nature. Although 80% of the clinical isolates harbored the trh hemolysin either alone or with tdh, and were urease positive, 14% harbored neither hemolysin exposing a limitation for these traits in pathogen detection. Resident sequence type (ST) 631 strains caused seven infections, and show a relatively recent history of recombination with other clinical and environmental lineages present in the region. ST34 and ST674 strains were each linked to a single infection and these strain types were also identified from the environment as isolates harboring hemolysin genes. Forty-two ST36 isolates were identified from the clinical collection, consistent with reports that this strain type caused a rise in regional infections starting in 2012. Whole-genome phylogenies that included three ST36 outbreak isolates traced to at least two local sources demonstrated that the US Atlantic coastal population of this strain type was indeed derived from the Pacific population. This study lays the foundation for understanding dynamics within natural populations associated with emergence and invasion of pathogenic strain types in the region. PMID:25904905

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

    PubMed Central

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

    2013-01-01

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

  3. Seasonal abundance of total and pathogenic Vibrio parahaemolyticus isolated from American oysters harvested in the Mandinga Lagoon System, Veracruz, Mexico: implications for food safety.

    PubMed

    Flores-Primo, Argel; Pardío-Sedas, Violeta; Lizárraga-Partida, Leonardo; López-Hernández, Karla; Uscanga-Serrano, Roxana; Flores-Hernández, Reyna

    2014-07-01

    The abundance of total and pathogenic Vibrio parahaemolyticus (Vp) strains in American oysters (Crassostrea virginica) harvested in two different harvest sites from the Mandinga lagoon System was evaluated monthly for 1 year (January through December 2012). Frequencies of species-specific genes and pathogenic genes exhibited a seasonal distribution. The annual occurrence of Vp with the species-specific tlh gene (tlh(+)) was significantly higher during the winter windy season (32.50%) and spring dry season (15.0%), with the highest densities observed during spring dry season at 283.50 most probable number (MPN)/g (lagoon bank A, near human settlements), indicating the highest risk of infection during warmer months. Pathogenic Vp tlh(+)/tdh(+) frequency was significantly higher during the winter windy and the spring dry seasons at 22.50 and 10.00%, respectively, with highest densities of 16.22 and 41.05 MPN/g (bank A), respectively. The tlh/trh and tdh/trh gene combinations were also found in Vp isolates during the spring dry season at 1.25 and 1.3%, respectively, with densities of 1.79 and 0.4 MPN/g (bank A), respectively. The orf8 genes were detected during the winter windy season (1.25%) with highest densities of 5.96 MPN/g (bank A) and 3.21 MPN/g (bank B, near mangrove islands and a heron nesting area). Densities of Vp tdh(+) were correlated (R(2) = 0.245, P < 0.015) with those of Vp orf8(+). The seasonal dynamics of Vp harboring pathogenic genes varied with seasonal changes, with very high proportions of Vp tdh(+) and Vp orf8(+) isolates in the winter windy season at 46.2 and 17.0%, respectively, which suggests that environmental factors may differentially affect the abundance of pathogenic subpopulations. Although all densities of total Vp (Vp tlh(+)) were lower than 10(4) MPN/g, thus complying with Mexican regulations, the presence of pathogenic strains is a public health concern. Our results suggest that total Vp densities may not be appropriate for assessing oyster contamination and predicting the risk of infection. Evaluation of the presence of pathogenic strains would be a better approach to protecting public health. PMID:24988011

  4. Transcriptomic and cellular response to bacterial challenge (pathogenic Vibrio parahaemolyticus) in farmed juvenile Haliotis rufescens fed with or without probiotic diet.

    PubMed

    Silva-Aciares, Fernando; Moraga, Dario; Auffret, Michel; Tanguy, Arnaud; Riquelme, Carlos

    2013-06-01

    The abalone production in Chile has increased considerably in recent years with no sign of tapering off. Open and semi-closed circuits in the marine water zones in the north and south of Chile are the preferred areas of culture. Coastal ecosystems are subjected to a wide variety of contaminants that generate stress that affects populations via their impacts to individuals at both physiological and genetic levels. This work investigated the genomic and cellular response of post-weaning juvenile Haliotis rufescens abalone under hatchery conditions, fed with probiotic diets, and subsequently challenged with Vibrio parahaemolyticus. The expression patterns of 16 selected genes associated with different metabolic pathways were analyzed using Real-Time PCR. Gene expression was then compared to immunological response parameters in the abalone and quantification of V. parahaemolyticus during the experimental period. Both transcriptomic and immunological analyses indicated significant alteration of physiological processes in H. rufescens correlated to exposure to the pathogenic bacteria, as well as to probiotic nutrition. PMID:23535139

  5. Vibrio species as agents of elasmobranch disease

    Microsoft Academic Search

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

    1984-01-01

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

  6. Epidemiological evidence of lesser role of thermostable direct hemolysin (TDH)-related hemolysin (TRH) than TDH on Vibrio parahaemolyticus pathogenicity.

    PubMed

    Saito, Shioko; Iwade, Yoshito; Tokuoka, Eisuke; Nishio, Tomohiro; Otomo, Yoshimitsu; Araki, Emiko; Konuma, Hirotaka; Nakagawa, Hiroshi; Tanaka, Hiroyuki; Sugiyama, Kanji; Hasegawa, Akio; Sugita-Konishi, Yoshiko; Hara-Kudo, Yukiko

    2015-02-01

    Vibrio parahaemolyticus carrying the tdh gene, encoding the thermostable direct hemolysin (TDH), or the trh gene, encoding the TDH-related hemolysin (TRH), are both considered virulent strains. There are, however, disproportionally fewer reports of infections caused by seafood contaminated with trh-positive strains than by seafood contaminated with tdh-positive strains. Bivalves such as clams and oysters are the major seafood varieties associated with the infections. In this study, the prevalence of strains possessing the tdh and trh genes was investigated in Japan in 74 samples collected in 2007-2008 and in 177 samples collected in 2010 of domestic bivalves, bloody clams, hen clams, short-neck clams, and rock oysters. The tdh-positive and trh-negative, tdh-negative and trh-positive, and tdh-positive and trh-positive samples represented 5.4%, 12.2%, and 4.1% of all samples collected in 2007-2008, and 5.1%, 18.6%, and 5.6% of all samples collected in 2010, respectively. As determined by polymerase chain reaction, the prevalence of tdh negative and trh positive in all samples was two to four times higher than that of tdh positive and trh negative. In the samples collected in 2010, the tdh-negative and trh-positive V. parahaemolyticus (20 samples) was more often isolated than tdh-positive and trh-negative V. parahaemolyticus (7 samples). The most common serotype of tdh-positive isolates (22 of 24 strains) was pandemic O3:K6. The trh-positive isolates (61 strains) were various serotypes including OUT:KUT. In 330 V. parahaemolyticus outbreaks and sporadic infections in Japan, most outbreaks and sporadic infections were caused by tdh-positive and trh-negative strains (89.4%). The frequencies of infections caused by tdh-negative and trh-positive, and both tdh- and trh-positive strains were 1.2% and 3.0%, respectively. This finding suggests that the virulence of trh might be less than that of tdh, although trh-positive V. parahaemolyticus frequently contaminated bivalves. PMID:25646967

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

    PubMed Central

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

    2014-01-01

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

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

    Microsoft Academic Search

    KASTHURI VENKATESWARAN; NOBUHIKO DOHMOTO; SHIGEAKI HARAYAMA

    1998-01-01

    Because biochemical testing and 16S rRNA sequence analysis have proven inadequate for the differentiation of Vibrio parahaemolyticus from closely related species, we employed the gyrase B gene (gyrB) as a molecular diagnostic probe. The gyrB genes of V. parahaemolyticus and closely related Vibrio alginolyticus were cloned and sequenced. Oligonucleotide PCR primers were designed for the amplification of a 285-bp fragment

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

    PubMed

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

    2014-10-01

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

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

    PubMed

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

    2012-10-01

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

  11. Occurrence of the three major Vibrio species pathogenic for human in seafood products consumed in France using real-time PCR.

    PubMed

    Robert-Pillot, Annick; Copin, Stéphanie; Himber, Charlotte; Gay, Mélanie; Quilici, Marie-Laure

    2014-10-17

    Vibrio spp. have emerged as a serious threat to human health worldwide. Vibrio parahaemolyticus, Vibrio cholerae and Vibrio vulnificus are of particular concern as they have been linked to gastrointestinal infections and septicemia associated with the consumption of raw or undercooked seafood. We developed hydrolysis probe-based real-time PCR systems with an internal amplification control for the detection of these species. We applied these systems to a total of 167 fresh or frozen crustacean, fish and shellfish samples consumed in France. Of them, 34.7% (n=58) were positive for Vibrio. V. parahaemolyticus was the most common, in 31.1% of samples, followed by V. vulnificus in 12.6% and V. cholerae in 0.6%. Furthermore, V. parahaemolyticus and V. vulnificus were present simultaneously in 9.6% of samples. Virulence genes (tdh and trh sequences) were present in 25% of the V. parahaemolyticus-positive samples. The V. cholerae strain detected was non toxigenic. The densities of V. parahaemolyticus and V. cholerae ranged from <10(2) to 10(4)bacteria/g of seafood. All samples positive for V. vulnificus displayed low-level contamination with fewer than 10(2)bacteria/g. Our findings indicate that seafood consumption presents a potential risk to human health in France and highlight the importance of tools for a preventive consumer protection policy. PMID:25128747

  12. Modified Dakin's solution for cutaneous vibrio infections.

    PubMed

    Wilhelmi, B J; Calianos, T A; Appelt, E A; Ortiz, M E; Heggers, J P; Phillips, L G

    1999-10-01

    Vibrio species, specifically Vibrio vulnificus, are known to be endemic to warm saltwater environments. As a human pathogen they are capable of causing severe, progressive, necrotizing infections. The lesions are bullous in nature and often require wide surgical debridement due to the aggressiveness of this organism. The literature supports prophylactic antibiotic therapy for those with preexisting hepatic dysfunction or immunocompromise. The authors routinely implement prophylactic antibiotic coverage with doxycycline 100 mg every 12 hours for vibrio in patients with wounds exposed to or acquired in saltwater. In addition, they institute topical therapy with 0.025% sodium hypochlorite solution (modified Dakin's), based on their in vitro study of vibrio sensitivity to antimicrobials. Over the past 2 years, the authors have treated 10 patients with this protocol for cutaneous vibrio infections confirmed by quantitative cultures. None of these patients experienced progression of infection requiring operative debridement-contrary to the aggressive nature of this organism documented in other reports. PMID:10517465

  13. Role of endosymbiotic zooxanthellae and coral mucus in the adhesion of the coral-bleaching pathogen Vibrio shiloi to its host

    Microsoft Academic Search

    Ehud Banin; Tomer Israely; Maoz Fine; Yossi Loya; Eugene Rosenberg

    2001-01-01

    Vibrio shiloi, the causative agent of bleaching the coral Oculina patagonica in the Mediterranean Sea, adheres to its coral host by a ?-D-galactopyranoside-containing receptor on the coral surface. The receptor is present in the coral mucus, since V. shiloi adhered avidly to mucus-coated ELISA plates. Adhesion was inhibited by methyl-?-D-galactopyranoside. Removal of the mucus from O. patagonica resulted in a

  14. Development of a Multiplex Real-Time PCR Assay with an Internal Amplification Control for the Detection of Total and Pathogenic Vibrio parahaemolyticus Bacteria in Oysters

    Microsoft Academic Search

    Jessica L. Nordstrom; Michael C. L. Vickery; George M. Blackstone; Shelley L. Murray; Angelo DePaola

    2007-01-01

    Vibrio parahaemolyticus is an estuarine bacterium that is the leading cause of shellfish-associated cases of bacterial gastroenteritis in the United States. Our laboratory developed a real-time multiplex PCR assay for the simultaneous detection of the thermolabile hemolysin (tlh), thermostable direct hemolysin (tdh), and thermostable-related hemolysin (trh) genes of V. parahaemolyticus. The tlh gene is a species- specific marker, while the

  15. Vibrio vulnificus dynamics in a south Texas bay

    E-print Network

    Meyer, Shelli Lee

    2009-05-15

    Vibrio vulnificus is a human pathogen commonly found in coastal and estuarine waters in temperate and subtropical regions across the world. The ecology of V. vulnificus has been studied in these regions primarily using cultured-based methods...

  16. Obacunone Represses Salmonella Pathogenicity Islands 1 and 2 in an envZ-Dependent Fashion

    PubMed Central

    Vikram, Amit; Jayaprakasha, Guddadarangavvanahally K.; Jesudhasan, Palmy R.

    2012-01-01

    Obacunone belongs to a class of unique triterpenoids called limonoids, present in Citrus species. Previous studies from our laboratory suggested that obacunone possesses antivirulence activity and demonstrates inhibition of cell-cell signaling in Vibrio harveyi and Escherichia coli O157:H7. The present work sought to determine the effect of obacunone on the food-borne pathogen Salmonella enterica serovar Typhimurium LT2 by using a cDNA microarray. Transcriptomic studies indicated that obacunone represses Salmonella pathogenicity island 1 (SPI1), the maltose transporter, and the hydrogenase operon. Furthermore, phenotypic data for the Caco-2 infection assay and maltose utilization were in agreement with microarray data suggesting repression of SPI1 and maltose transport. Further studies demonstrated that repression of SPI1 was plausibly mediated through hilA. Additionally, obacunone seems to repress SPI2 under SPI2-inducing conditions as well as in Caco-2 infection models. Furthermore, obacunone seems to repress hilA in an EnvZ-dependent fashion. Altogether, the results of the study seems to suggest that obacunone exerts an antivirulence effect on S. Typhimurium and may serve as a lead compound for development of antivirulence strategies for S. Typhimurium. PMID:22843534

  17. Vibrio and Pregnancy

    MedlinePLUS

    ... takes over an area after a hurricane or flood may contain Vibrio bacteria. You should try to ... Available at URL: http://www.cdc.gov/vibrio/index.html Centers for Disease Control and Prevention.2013. ...

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

    PubMed Central

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

    2011-01-01

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

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

    ERIC Educational Resources Information Center

    Hrizo, Stacy L.; Kaufmann, Nancy

    2009-01-01

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

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

    PubMed

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

    2013-04-01

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

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

    PubMed

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

    2012-09-01

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

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

    PubMed

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

    2015-02-01

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

  3. Vibrio species as agents of elasmobranch disease

    NASA Astrophysics Data System (ADS)

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

    1984-03-01

    Two Vibrio species identified as V. damsela and a new sucrose-positive Vibrio sp., V. carchariae sp. nov., were simultaneously isolated from a brown shark which died while being held in captivity at a large aquarium. Pathogenicity studies were subsequently conducted using a variety of elasmobranchs, including smooth dogfish and lemon sharks. Both bacterial strains proved pathogenic, causing death in nearly all of the elasmobranch hosts challenged. Virulence studies revealed that both bacterial strains were cytotoxic for Y-1 mouse adrenal cells. The V. damsela strain was highly cytotoxic causing Y-1 cellular damage at culture supernatant dilutions up to 1 : 128. Both strains were hemolytic, but neither exhibited the Kanagawa phenomenon. They were both capable of urea hydrolysis, an interesting trait, considering that elasmobranchs retain large (ca 300 milliosmolal) urea concentration in their tissue.

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

    PubMed Central

    Ding, Jun; Dou, Yan; Wang, Yinan

    2014-01-01

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

  5. Features of cholera and Vibrio parahaemolyticus diarrhoea endemicity in Calabar, Nigeria

    Microsoft Academic Search

    S. J. Utsalo; F. O. Eko; E. O. Antia-Obong

    1992-01-01

    The clinical and epidemiological features of acute vibrio diarrhoeal disease were studied in 881 patients seen at the University of Calabar Teaching Hospital (UCTH), Calabar, Nigeria, between January and December 1989. Stools and rectal swabs of patients and randomly-selected control subjects were microscopically and culturally examined for the presence of enteric pathogens. Households of vibrio diarrhoea cases and matched controls

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

    PubMed

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

    2015-01-01

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

  7. Local Mobile Gene Pools Rapidly Cross Species Boundaries To Create within Global Vibrio cholerae Populations

    E-print Network

    Boucher, Yan

    Vibrio cholerae represents both an environmental pathogen and a widely distributed microbial species comprised of closely related strains occurring in the tropical to temperate coastal ocean across the globe (Colwell RR, ...

  8. Presence of genes for type III secretion system 2 in Vibrio mimicus strains

    Microsoft Academic Search

    Natsumi Okada; Shigeaki Matsuda; Junko Matsuyama; Kwon-Sam Park; Calvin de los Reyes; Kazuhiro Kogure; Takeshi Honda; Tetsuya Iida

    2010-01-01

    Background  Vibrios, which include more than 100 species, are ubiquitous in marine and estuarine environments, and several of them e.g.\\u000a Vibrio cholerae, V. parahaemolyticus, V. vulnificus and V. mimicus, are pathogens for humans. Pathogenic V. parahaemolyticus strains possess two sets of genes for type III secretion system (T3SS), T3SS1 and T3SS2. The latter are critical for virulence\\u000a of the organism and

  9. Origin of Vibrio parahaemolyticus O3:K6 pandemic clone

    Microsoft Academic Search

    Guoxiang Chao; Fang Wang; Xiaohui Zhou; Xinan Jiao; Jinlin Huang; Zhiming Pan; Liping Zhou; Xiaoqin Qian

    2011-01-01

    O3:K6 pandemic clone of Vibrio parahaemolyticus has caused outbreaks in coastal countries since 1996. Mutilocus sequence typing (MLST) is an important tool to trace the source and analysis the evolution of bacteria. Based on MLST, the first pandemic clonal complex (CC) of V. parahaemolyticus has been confirmed. In this study, 57 pandemic strains, 27 pathogenic strains (tdh or trh positive)

  10. Identification of the target DNA sequence and characterization of DNA binding features of HlyU, and suggestion of a redox switch for hlyA expression in the human pathogen Vibrio cholerae from in silico studies.

    PubMed

    Mukherjee, Debadrita; Pal, Aritrika; Chakravarty, Devlina; Chakrabarti, Pinak

    2015-02-18

    HlyU, a transcriptional regulator common in many Vibrio species, activates the hemolysin gene hlyA in Vibrio cholerae, the rtxA1 operon in Vibrio vulnificus and the genes of plp-vah1 and rtxACHBDE gene clusters in Vibrio anguillarum. The protein is also proposed to be a potential global virulence regulator for V. cholerae and V. vulnificus. Mechanisms of gene control by HlyU in V. vulnificus and V. anguillarum are reported. However, detailed elucidation of the interaction of HlyU in V. cholerae with its target DNA at the molecular level is not available. Here we report a 17-bp imperfect palindrome sequence, 5'-TAATTCAGACTAAATTA-3', 173 bp upstream of hlyA promoter, as the binding site of HlyU. This winged helix-turn-helix protein binds necessarily as a dimer with the recognition helices contacting the major grooves and the ?-sheet wings, the minor grooves. Such interactions enhance hlyA promoter activity in vivo. Mutations affecting dimerization as well as those in the DNA-protein interface hamper DNA binding and transcription regulation. Molecular dynamic simulations show hydrogen bonding patterns involving residues at the mutation sites and confirmed their importance in DNA binding. On binding to HlyU, DNA deviates by ?68º from linearity. Dynamics also suggest a possible redox control in HlyU. PMID:25605793

  11. Draft Genome Sequence of Environmental Vibrio cholerae 2012EL-1759 with Similarities to the V. cholerae O1 Classical Biotype.

    PubMed

    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. PMID:25013135

  12. Vibrio azureus sp. nov., a luminous marine bacterium isolated from seawater.

    PubMed

    Yoshizawa, Susumu; Wada, Minoru; Kita-Tsukamoto, Kumiko; Ikemoto, Eiko; Yokota, Akira; Kogure, Kazuhiro

    2009-07-01

    Two luminous marine bacterial strains, LC2-005(T) and LC2-102, were isolated from seawater at Kuroshio Region and Sagami Bay in Japan, respectively. These bacteria were Gram-negative, oxidase-positive, catalase-positive, motile and rod-shaped. On the basis of 16S rRNA gene sequence analysis, strains LC2-005(T) and LC2-102 formed a cluster within the Vibrio harveyi species group. However, multilocus sequence analysis using five loci (pyrH, ftsZ, mreB, gyrB and gapA) and DNA-DNA hybridization experiments indicated that these strains were distinct from the currently known Vibrio species. Additionally, these strains differ from related Vibrio species in utilization of glucose, mannitol, inositol, sorbitol, rhamnose, sucrose, melibiose and arabinose, production of lysine decarboxylase, ornithine decarboxylase, tryptophan deaminase, esterase (C4), lipase (C4), chymotrypsin, acid phosphatase, alpha-glucosidase, beta-glucosidase and N-acetyl-beta-glucosaminidase and the ability to reduce nitrate to nitrite. The major fatty acids were C(15 : 0) iso 2-OH and/or C(16 : 1)omega7c, C(16 : 0), C(18 : 1)omega7c and C(14 : 0). The DNA G+C contents of strains LC2-005(T) and LC2-102 were 45.2 and 45.5 mol%, respectively. On the basis of the polyphasic taxonomic evidence presented in this study, it can be concluded that strains LC2-005(T) and LC2-102 belong to the same genospecies and represent a novel species of the genus Vibrio, for which the name Vibrio azureus sp. nov. is proposed. The type strain is LC2-005(T) (=NBRC 104587(T) =KCTC 22352(T)). PMID:19542136

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

    PubMed

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

    2014-09-01

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

  14. Population dynamics of vibrio species in the river Narmada at Jabalpur.

    PubMed

    Sharma, Anjana; Chaturvedi, Animesh Navin

    2007-10-01

    Several studies on the presence and ecology of various Vibrio sp have been reported in coastal and estuarine waters throughout the world, but there is trifling information available on the distribution of this organism of colossal pathogenic potential in the fresh water riverine environment. Thus, we conducted a multiyearenvironmental study to scrutinize the occurrence of members of genus Vibrio in the largest west flowing river of the Indian subcontinent, which is also the largest river of central India, the Narmada. Statistical analysis was done to reveal major environmental factors controlling the presence of Vibrio sp in the river Narmada. Monthly field samplings were conducted between January 2002 and December 2003 at four different sites in Jabalpur (MP), India. At each site, water samples were taken and physicochemical and bacteriological parameters were measured. The identity of the isolates was confirmed by employing 16S rRNA analysis. The organisms were found to be widely distributed in the river with regular seasonal variations. The density of Vibrio was found to be correlated with temperature, coliforms and other heterotrophic bacteria. Water temperature accounted for most of the variability in the concentration of Vibrio spAs typical fecal pollution indicators may not access public health risk from potential pathogens such as vibrios, hence special monitoring programme for vibrios may adequately be included in the water quality management. PMID:18405107

  15. Vibrio cholerae and Vibrio parahaemolyticus detected in seafood products from Senegal.

    PubMed

    Coly, Ignace; Sow, Amy Gassama; Seydi, Malang; Martinez-Urtaza, Jaime

    2013-12-01

    The detection of pathogenic Vibrio in seafood from Senegal has generated five food alerts in the European Union. To investigate the presence and abundance Vibrio cholerae and Vibrio parahaemolyticus in seafood and coastal and estuarine waters, 123 seafood samples and 52 water samples were collected during 2007-2009 from two large seafood markets in Dakar, and from different oceanic and estuarine areas of the country. V. parahaemolyticus was detected in 30.1% of seafood samples, whereas presence of V. cholerae was only found in 1.6%. In water samples, V. parahaemolyticus and V. cholerae were detected in 28.8% and 5.7% of the samples, respectively. Abundance of V. parahaemolyticus in seafood from the fishing areas ranged from <0.3 to 7.5 most probable number (MPN) per gram. In samples from markets, densities of V. parahaemolyticus showed higher values ranging from 0.61 to >110 MPN/g. Densities of V. cholerae in the two positive seafood samples reached values of 0.36 and 0.61 MPN/g, repectively. V. parahaemolyticus strains were found to possess tlh, but not tdh and trh by polymerase chain reaction, and all the strains of V. cholerae were non-O1 or non-O139. These results suggest that the prevalence of high salinities in coastal and estuarine environments of Senegal limits the occurrence of V. parahaemolyticus and V. cholerae, despite warmer temperatures prevailing in seawater environments throughout the year. Furthermore, temperature abuse driven by a deficient cold chain over the distribution and retail sales may represent a major risk due to the postharvest multiplication of these Vibrio pathogens. PMID:24147655

  16. Draft Genome Sequence of Vibrio parahaemolyticus VH3, Isolated from an Aquaculture Environment in Greece.

    PubMed

    Castillo, Daniel; Jun, Jin Woo; D'Alvise, Paul; Middelboe, Mathias; Gram, Lone; Liu, Siyang; Katharios, Pantelis

    2015-01-01

    Vibrio parahaemolyticus is an important foodborne pathogen responsible for gastroenteritis outbreaks globally. It has also been identified as an important pathogen in aquatic organisms. Here, we report a draft genome sequence of V. parahaemolyticus, strain VH3, isolated from farmed juvenile greater amberjack, Seriola dumerili, in Greece. PMID:26139725

  17. Evidence that Water TransmitsVibrio vulnificus Biotype 2 Infections to Eels

    Microsoft Academic Search

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

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

  18. Draft Genome Sequence of Vibrio parahaemolyticus VH3, Isolated from an Aquaculture Environment in Greece

    PubMed Central

    Castillo, Daniel; Jun, Jin Woo; D’Alvise, Paul; Middelboe, Mathias; Gram, Lone; Liu, Siyang

    2015-01-01

    Vibrio parahaemolyticus is an important foodborne pathogen responsible for gastroenteritis outbreaks globally. It has also been identified as an important pathogen in aquatic organisms. Here, we report a draft genome sequence of V. parahaemolyticus, strain VH3, isolated from farmed juvenile greater amberjack, Seriola dumerili, in Greece. PMID:26139725

  19. Integrative genome-scale metabolic analysis of Vibrio vulnificus for drug targeting and discovery

    Microsoft Academic Search

    Hyun Uk Kim; Soo Young Kim; Haeyoung Jeong; Tae Yong Kim; Jae Jong Kim; Hyon E Choy; Kyu Yang Yi; Joon Haeng Rhee; Sang Yup Lee

    2011-01-01

    Although the genomes of many microbial pathogens have been studied to help identify effective drug targets and novel drugs, such efforts have not yet reached full fruition. In this study, we report a systems biological approach that efficiently utilizes genomic information for drug targeting and discovery, and apply this approach to the opportunistic pathogen Vibrio vulnificus CMCP6. First, we partially

  20. Genome Sequence of Vibrio cholerae Strain O1 Ogawa El Tor, Isolated in Mexico, 2013

    PubMed Central

    Hernández-Monroy, Irma; López-Martínez, Irma; Ortiz-Alcántara, Joanna; González-Durán, Elizabeth; Ruiz-Matus, Cuitláhuac; Kuri-Morales, Pablo; Ramírez-González, José Ernesto

    2014-01-01

    We present the draft genome sequence of Vibrio cholerae InDRE 3140 recovered in 2013 during a cholera outbreak in Mexico. The genome showed the Vibrio 7th pandemic islands VSP1 and VSP2, the pathogenic islands VPI-1 and VPI-2, the integrative and conjugative element SXT/R391 (ICE-SXT), and both prophages CTX? and RS1?. PMID:25359919

  1. Genome Sequence of Vibrio cholerae Strain O1 Ogawa El Tor, Isolated in Mexico, 2013.

    PubMed

    Díaz-Quiñonez, José Alberto; Hernández-Monroy, Irma; López-Martínez, Irma; Ortiz-Alcántara, Joanna; González-Durán, Elizabeth; Ruiz-Matus, Cuitláhuac; Kuri-Morales, Pablo; Ramírez-González, José Ernesto

    2014-01-01

    We present the draft genome sequence of Vibrio cholerae InDRE 3140 recovered in 2013 during a cholera outbreak in Mexico. The genome showed the Vibrio 7th pandemic islands VSP1 and VSP2, the pathogenic islands VPI-1 and VPI-2, the integrative and conjugative element SXT/R391 (ICE-SXT), and both prophages CTX? and RS1?. PMID:25359919

  2. Rapid detection of intestinal pathogens in fecal samples by an improved reverse dot blot method

    Microsoft Academic Search

    Jian-Ming Xing; Li-Hui Yao; Leonidas G Koniaris; Xing JM

    2009-01-01

    AIM: To develop a new, rapid and accurate reverse dot blot (RDB) method for the detection of intestinal pathogens in fecal samples. METHODS: The 12 intestinal pathogens tested were Salmonella spp., Brucella spp., Escherichia coli O157:H7, Clostridium botulinum , Bacillus cereus , Clostridium perfringens , Vibrio parahaemolyticus , Shigella spp., Yersinia enterocolitica , Vibrio cholerae , Listeria monocytogenes and Staphylococcus

  3. Increased seawater temperature increases the abundance and alters the structure of natural Vibrio populations associated with the coral Pocillopora damicornis.

    PubMed

    Tout, Jessica; Siboni, Nachshon; Messer, Lauren F; Garren, Melissa; Stocker, Roman; Webster, Nicole S; Ralph, Peter J; Seymour, Justin R

    2015-01-01

    Rising seawater temperature associated with global climate change is a significant threat to coral health and is linked to increasing coral disease and pathogen-related bleaching events. We performed heat stress experiments with the coral Pocillopora damicornis, where temperature was increased to 31°C, consistent with the 2-3°C predicted increase in summer sea surface maxima. 16S rRNA amplicon sequencing revealed a large shift in the composition of the bacterial community at 31°C, with a notable increase in Vibrio, including known coral pathogens. To investigate the dynamics of the naturally occurring Vibrio community, we performed quantitative PCR targeting (i) the whole Vibrio community and (ii) the coral pathogen Vibrio coralliilyticus. At 31°C, Vibrio abundance increased by 2-3 orders of magnitude and V. coralliilyticus abundance increased by four orders of magnitude. Using a Vibrio-specific amplicon sequencing assay, we further demonstrated that the community composition shifted dramatically as a consequence of heat stress, with significant increases in the relative abundance of known coral pathogens. Our findings provide quantitative evidence that the abundance of potential coral pathogens increases within natural communities of coral-associated microbes as a consequence of rising seawater temperature and highlight the potential negative impacts of anthropogenic climate change on coral reef ecosystems. PMID:26042096

  4. Increased seawater temperature increases the abundance and alters the structure of natural Vibrio populations associated with the coral Pocillopora damicornis

    PubMed Central

    Tout, Jessica; Siboni, Nachshon; Messer, Lauren F.; Garren, Melissa; Stocker, Roman; Webster, Nicole S.; Ralph, Peter J.; Seymour, Justin R.

    2015-01-01

    Rising seawater temperature associated with global climate change is a significant threat to coral health and is linked to increasing coral disease and pathogen-related bleaching events. We performed heat stress experiments with the coral Pocillopora damicornis, where temperature was increased to 31°C, consistent with the 2–3°C predicted increase in summer sea surface maxima. 16S rRNA amplicon sequencing revealed a large shift in the composition of the bacterial community at 31°C, with a notable increase in Vibrio, including known coral pathogens. To investigate the dynamics of the naturally occurring Vibrio community, we performed quantitative PCR targeting (i) the whole Vibrio community and (ii) the coral pathogen Vibrio coralliilyticus. At 31°C, Vibrio abundance increased by 2–3 orders of magnitude and V. coralliilyticus abundance increased by four orders of magnitude. Using a Vibrio-specific amplicon sequencing assay, we further demonstrated that the community composition shifted dramatically as a consequence of heat stress, with significant increases in the relative abundance of known coral pathogens. Our findings provide quantitative evidence that the abundance of potential coral pathogens increases within natural communities of coral-associated microbes as a consequence of rising seawater temperature and highlight the potential negative impacts of anthropogenic climate change on coral reef ecosystems. PMID:26042096

  5. Distribution of Vibrio vulnificus and Other Lactose-Fermenting Vibrios in the Marine Environment

    PubMed Central

    Oliver, James D.; Warner, Robert A.; Cleland, David R.

    1983-01-01

    During the summer of 1981, 3,887 sucrose-negative vibrios were isolated from seawater, sediment, plankton, and animal samples taken from 80 sites from Miami, Fla., to Portland, Maine. Of these, 4.2% were able to ferment lactose. The lactose-positive strains isolated from the various samples correlated positively with pH and turbidity of the water, vibrios in the sediment and oysters, and total bacterial counts in oysters. Negative correlations were obtained for water salinity. Numerical taxonomy was performed on 95 of the lactose-fermenting environmental isolates and 23 reference strains. Five clusters resulted, with the major cluster containing 33 of the environmental isolates and all of the Vibrio vulnificus reference strains. The 33 isolates, which produced an acid reaction in lactose broth within hours of initial inoculation, represented 20% of all lactose-fermenting vibrios studied. These isolates were nearly identical phenotypically to clinical strains of V. vulnificus studied by the Centers for Disease Control, Atlanta, Ga., and by our laboratory, and their identification was confirmed by DNA-DNA hybridization studies. V. vulnificus was isolated from all sample types and from Miami to Cape Cod, Mass., and comparison of the environmental parameters of the eight subsites yielding this species with those of all 80 subsites revealed no significant differences. The majority of the isolates were obtained from animals, with clams providing most (84%) of these. On injection into mice, 82% of the V. vulnificus isolates resulted in death. Members of the remaining four clusters contained strains which differed from V. vulnificus in such phenotypic traits as luminescence and in urease or H2S production. None of the other reference cultures, including nine other Vibrio species, were contained in the remaining clusters, and these isolates could not be identified. Most of these were also lethal for mice. Phenotypic differences, potential pathogenicity, and geographic distribution of the five clusters were examined. It is concluded that V. vulnificus is a ubiquitous organism, both geographically and in a variety of environmental sources, although it occurs in relatively low numbers. The public health significance of this organism and of the other unidentified lactose-fermenting Vibrio species is discussed. PMID:6847190

  6. Laboratory studies on the El Tor vibrio

    PubMed Central

    Sayamov, R. M.

    1963-01-01

    The identity of the El Tor vibrio is a controversial question that the usual methods of bacteriological investigation have as yet failed to settle. In this paper, the author presents the results of a study of the interrelationships between El Tor vibrios, true cholera vibrios and water vibrios, as revealed by the behaviour of the vibrios in the bile system and in the small intestine of experimental animals. The vibrios investigated included two strains isolated at the El Tor quarantine station on the Sinai Peninsula in 1934, two strains isolated at Makassar, Celebes, during a cholera epidemic in 1937 and identified as “El Tor” vibrios, four strains of true cholera vibrios and five strains of water vibrios. On the whole, the behaviour of the El Tor and Makassar vibrios was similar, closely resembling that of the cholera vibrios and differing markedly from that of the water vibrios. The author therefore considers that the strains of El Tor and Makassar vibrios examined are varieties of Vibrio cholerae and suggests that carriers of such strains should be subjected to the same measures as carriers of true cholera vibrios. ImagesFIG. 1FIG. 2FIG. 3FIG. 4FIG. 5FIG. 6FIG. 7FIG. 8 PMID:13986981

  7. Antimicrobial Susceptibility of Vibrio vulnificus and Vibrio parahaemolyticus Recovered from Recreational and Commercial Areas of Chesapeake Bay and Maryland Coastal Bays

    PubMed Central

    Shaw, Kristi S.; Rosenberg Goldstein, Rachel E.; He, Xin; Jacobs, John M.; Crump, Byron C.; Sapkota, Amy R.

    2014-01-01

    Vibrio vulnificus and V. parahaemolyticus in the estuarine-marine environment are of human health significance and may be increasing in pathogenicity and abundance. Vibrio illness originating from dermal contact with Vibrio laden waters or through ingestion of seafood originating from such waters can cause deleterious health effects, particularly if the strains involved are resistant to clinically important antibiotics. The purpose of this study was to evaluate antimicrobial susceptibility among these pathogens. Surface-water samples were collected from three sites of recreational and commercial importance from July to September 2009. Samples were plated onto species-specific media and resulting V. vulnificus and V. parahaemolyticus strains were confirmed using polymerase chain reaction assays and tested for antimicrobial susceptibility using the Sensititre® microbroth dilution system. Descriptive statistics, Friedman two-way Analysis of Variance (ANOVA) and Kruskal-Wallis one-way ANOVA were used to analyze the data. Vibrio vulnificus (n?=?120) and V. parahaemolyticus (n?=?77) were isolated from all sampling sites. Most isolates were susceptible to antibiotics recommended for treating Vibrio infections, although the majority of isolates expressed intermediate resistance to chloramphenicol (78% of V. vulnificus, 96% of V. parahaemolyticus). Vibrio parahaemolyticus also demonstrated resistance to penicillin (68%). Sampling location or month did not significantly impact V. parahaemolyticus resistance patterns, but V. vulnificus isolates from St. Martin's River had lower overall intermediate resistance than that of the other two sampling sites during the month of July (p?=?0.0166). Antibiotics recommended to treat adult Vibrio infections were effective in suppressing bacterial growth, while some antibiotics recommended for pediatric treatment were not effective against some of the recovered isolates. To our knowledge, these are the first antimicrobial susceptibility data of V. vulnificus and V. parahaemolyticus recovered from the Chesapeake Bay. These data can serve as a baseline against which future studies can be compared to evaluate whether susceptibilities change over time. PMID:24586914

  8. Whole-Genome Sequencing of a Vibrio cholerae El Tor Strain Isolated in the Imported Cholera Focus in Siberia

    PubMed Central

    Balakhonov, S. V.; Basov, E. A.; Gladkikh, A. S.; Afanasev, M. V.; Ganin, V. S.; Urbanovich, L. Y.; Sidorova, E. A.

    2015-01-01

    The draft genome sequence of Vibrio cholerae O1 strain I-1263, isolated from a patient in the imported focus in Siberia, was determined. The established structural features of the mobile genetic elements indicate stage-by-stage formation of a highly pathogenic V. cholerae clone and promote understanding of the mechanisms of evolutionary pathogen transformations. PMID:25814617

  9. Effects of Hypercapnic Hypoxia on the Clearance of Vibrio campbellii in the Atlantic Blue Crab, Callinectes sapidus Rathbun

    Microsoft Academic Search

    JEREMY D. HOLMAN; KAREN G. BURNETT; LOUIS E. BURNETT

    2004-01-01

    Callinectes sapidus, the Atlantic blue crab, en- counters hypoxia, hypercapnia (elevated CO2), and bacterial pathogens in its natural environment. We tested the hypoth- esis that acute exposure to hypercapnic hypoxia (HH) alters the crab's ability to clear a pathogenic bacterium, Vibrio campbellii 90 - 69B3, from the hemolymph. Adult male crabs were held in normoxia (well-aerated seawater) or HH (seawater

  10. Molecular, Serological, and Virulence Characteristics of Vibrio parahaemolyticus Isolated from Environmental, Food, and Clinical Sources in North America and Asia

    Microsoft Academic Search

    Angelo DePaola; Jodie Ulaszek; Charles A. Kaysner; Bradley J. Tenge; Jessica L. Nordstrom; Joy Wells; Nancy Puhr; Steven M. Gendel

    2003-01-01

    Potential virulence attributes, serotypes, and ribotypes were determined for 178 pathogenic Vibrio parahae- molyticus isolates from clinical, environmental, and food sources on the Pacific, Atlantic, and Gulf Coasts of the United States and from clinical sources in Asia. The food and environmental isolates were generally from oysters, and they were defined as being pathogenic by using DNA probes to detect

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

    PubMed

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

    2014-01-01

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

  12. Intestinal Colonization Dynamics of Vibrio cholerae

    PubMed Central

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

    2015-01-01

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

  13. Diversity and dynamics of the Vibrio community in well water used for drinking in Guinea-Bissau (West Africa).

    PubMed

    Machado, A; Bordalo, A A

    2014-09-01

    Bacteria of the genus Vibrio are ubiquitous in aquatic environments and can be found either in culturable or in a viable but nonculturable (VBNC) state. The genus comprises many pathogenic species accountable for water and food-borne diseases that prove to be fatal, especially in developing countries, as in Guinea-Bissau (West Africa), where cholera is endemic. In order to ascertain the abundance and structure of Vibrio spp. community in well waters that serve as the sole source of water for the population, quantitative polymerase chain reaction (qPCR), PCR-denaturant gradient gel electrophoresis (DGGE), and cloning approaches were used. Results suggest that Vibrio spp. were present throughout the year in acidic, freshwater wells with a seasonal community composition shift. Vibrio spp. abundance was in accordance with the abundance found in coastal environments. Sequences closely related to pathogenic Vibrio species were retrieved from well water revealing exposure of the population to such pathogens. pH, ammonium, and turbidity, regulated by the rain pattern, seem to be the variables that contributed mostly to the shaping and selection of the Vibrio spp. community. These results reinforce the evidence for water monitoring with culture-independent methods and the clear need to create/recover water infrastructures and a proper water resources management in West African countries with similar environmental conditions. PMID:24859857

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

    PubMed Central

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

    2013-01-01

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

  15. Detection and quantification of Vibrio populations using denaturant gradient gel electrophoresis.

    PubMed

    Eiler, Alexander; Bertilsson, Stefan

    2006-11-01

    Bacteria affiliated with the genus Vibrio are endemic in marine and estuarine ecosystems and are also found in many freshwater environments. Vibrios can enter viable but non-culturable states and since many species are pathogenic, there is a great need for culture-independent methods that identify and quantify multiple Vibrio populations. We adopted Vibrio-specific 16S rRNA-directed primers and a competitive PCR protocol (QC-PCR; [Thompson, J.R., Randa, M.A., Marcelino, L.A., Tomita-Mitchell, A., Lim, E., Polz, M.F., 2004b. Diversity and dynamics of a North Atlantic coastal Vibrio community. Appl. Environ. Microbiol. 70, 4103-4110]) for separation and quantification of Vibrio populations using denaturant gradient gel electrophoresis (DGGE). Sixteen Vibrio isolates and eight environmental samples were used to assess the precision and resolution of the method. A 45-70% gradient of Urea and formamide enabled separation of Vibrio populations with single nucleotide differences in the amplified fragment. A titration curve for the QC-PCR-DGGE, verified by amending surface water bacterioplankton samples with up to 3 x 10(5)Vibrio cholerae cells, could be approximated by a linear regression of log-transformed values (R(2)=0.96). The limit of detection for single populations was 180 cells per extracted sample or about 4 cells per PCR reaction. Environmental samples from the southern Stockholm archipelago in the Baltic Sea and the more saline coastal waters of Skagerrak each carried between 2 and 6 Vibrio populations, and there were major differences between the locations. Notably, multiple Vibrio populations could be detected and quantified against a background of native bacterioplankton exceeding Vibrio population abundance by more than 6 orders of magnitude. Putative identification based on migration in the DGGE gel was verified by parallel cloning and sequencing of PCR products, and representative clones were also characterized by DGGE. This general approach could also be useful for targeting other phylogenetically constrained bacterial groups and assess their abundance and distribution in complex environmental settings. PMID:16730823

  16. A Bistable Switch and Anatomical Site Control Vibrio cholerae Virulence Gene Expression in the Intestine

    Microsoft Academic Search

    Alex T. Nielsen; Nadia A. Dolganov; Thomas Rasmussen; Glen Otto; Michael C. Miller; Stephen A. Felt; Stéphanie Torreilles; Gary K. Schoolnik

    2010-01-01

    A fundamental, but unanswered question in host-pathogen interactions is the timing, localization and population distribution of virulence gene expression during infection. Here, microarray and in situ single cell expression methods were used to study Vibrio cholerae growth and virulence gene expression during infection of the rabbit ligated ileal loop model of cholera. Genes encoding the toxin-coregulated pilus (TCP) and cholera

  17. UPTAKE, PERSISTENCE, AND LOCALIZATION OF VIRULENT AND AVIRULENT VIBRIO VULNIFICUS IN THE EASTERN OYSTER, CRASSOSTREA VIRGINICA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vibrio vulnificus is a human pathogen commonly found in estuarine environments. Foodborne illness is associated with the consumption of raw oysters and can produce gastroenteritis and life-threatening septicemia. Depuration is one of the common methods to purge microbial contaminants from oysters....

  18. Characterization of Vibrio fluvialis-Like Strains Implicated in Limp Lobster Disease

    Microsoft Academic Search

    B. D. Tall; S. Fall; M. R. Pereira; M. Ramos-Valle; S. K. Curtis; M. H. Kothary; D. M. T. Chu; S. R. Monday; L. Kornegay; T. Donkar; D. Prince; R. L. Thunberg; K. A. Shangraw; D. E. Hanes; F. M. Khambaty; K. A. Lampel; J. W. Bier; R. C. Bayer

    2003-01-01

    Studies were undertaken to characterize and determine the pathogenic mechanisms involved in a newly described systemic disease in Homarus americanus (American lobster) caused by a Vibrio fluvialis-like micro- organism. Nineteen isolates were obtained from eight of nine lobsters sampled. Biochemically, the isolates resembled V. fluvialis, and the isolates grew optimally at 20°C; none could grow at temperatures above 23°C. The

  19. Comparing the efficiency of chitosan with chlorine for reducing Vibrio parahaemolyticus in shrimp

    Microsoft Academic Search

    S. Chaiyakosa; W. Charernjiratragul; K. Umsakul; V. Vuddhakul

    2007-01-01

    Thailand is one of the leading exporters of frozen shrimp to many countries. Chlorine is the decontaminating agent most frequently used in the frozen shrimp industries to kill potential pathogens. However, long time contact to chlorine causes severe respiratory tract damage. In this study, chitosan was compared to chlorine for reducing Vibrio parahaemolyticus. In vitro investigation, chitosan could reduce more

  20. Vibrio furnissii: an Unusual Cause of Bacteremia and Skin Lesions after Ingestion of Seafood?†

    PubMed Central

    Derber, Catherine; Coudron, Philip; Tarr, Cheryl; Gladney, Lori; Turnsek, Maryann; Shankaran, Shivanjali; Wong, Edward

    2011-01-01

    Vibrio furnissii in the blood is rarely reported, which may explain why clinical features of bloodstream infections with this organism have not been described. We describe a patient who developed skin lesions and V. furnissii bacteremia and was successfully treated with fluoroquinolones. V. furnissii may be a serious pathogen in patients with underlying comorbidities who are exposed to seafood. PMID:21450956

  1. Determination of Molecular Phylogenetics of Vibrio parahaemolyticus Strains by Multilocus Sequence Typing

    Microsoft Academic Search

    Narjol Gonzalez-Escalona; Jaime Martinez-Urtaza; Jaime Romero; Romilio T. Espejo; Lee-Ann Jaykus; Angelo DePaola

    2008-01-01

    Vibrio parahaemolyticus is an important human pathogen whose transmission is associated with the con- sumption of contaminated seafood. There is a growing public health concern due to the emergence of a pandemic strain causing severe outbreaks worldwide. Many questions remain unanswered regarding the evolution and population structure of V. parahaemolyticus. In this work, we describe a multilocus sequence typing (MLST)

  2. Ultrasensitive detection of Vibrio cholerae O1 using microcantilever-based biosensor with dynamic force microscopy

    Microsoft Academic Search

    Assawapong Sappat; Anurat Wisitsoraat; Chamras Promptmas; Adisorn Tuantranont

    2010-01-01

    This work presents the first demonstration of a cantilever based cholerae sensor. Dynamic force microscopy within atomic force microscope (AFM) is applied to measure the cantilever's resonance frequency shift due to mass of cell bound on microcantilever surface. The Vibrio cholerae O1, a food and waterborne pathogen that caused cholera disease in human, is a target bacterium cell of interest.

  3. Draft Genome Sequence of Israeli Outbreak-Associated Vibrio vulnificus Biotype 3 Clinical Isolate BAA87.

    PubMed

    Phillips, Kelsey E; Schipma, Matthew J; Satchell, Karla J F

    2014-01-01

    Vibrio vulnificus is a seafood-associated pathogen that causes severe wound and intestinal infections. Biotype 3 of V. vulnificus emerged in 1996 as the cause of an Israeli outbreak associated with the handling of infected tilapia. Here, we describe the whole-genome sequence of the ATCC biotype 3 clinical isolate BAA87 (CDC9530-96). PMID:24652973

  4. Insights into Vibrio cholerae Intestinal Colonization from Monitoring Fluorescently Labeled Bacteria

    E-print Network

    von Andrian, Ulrich H.

    Insights into Vibrio cholerae Intestinal Colonization from Monitoring Fluorescently Labeled-invasive pathogen that colonizes the small intestine (SI). Most of our knowledge of the processes required for V. cholerae intestinal colonization is derived from enumeration of wt and mutant V. cholerae recovered from

  5. A Role for the Mannose-Sensitive Hemagglutinin in Biofilm Formation by Vibrio cholerae El Tor

    Microsoft Academic Search

    PAULA I. WATNICK; KARLA JEAN FULLNER; ROBERTO KOLTER

    1999-01-01

    While much has been learned regarding the genetic basis of host-pathogen interactions, less is known about the molecular basis of a pathogen's survival in the environment. Biofilm formation on abiotic surfaces represents a survival strategy utilized by many microbes. Here it is shown that Vibrio cholerae El Tor does not use the virulence-associated toxin-coregulated pilus to form biofilms on borosilicate

  6. Ingestion of bacteria overproducing DnaK attenuates Vibrio infection of Artemia franciscana larvae

    Microsoft Academic Search

    Yeong Yik Sung; Till Dhaene; Tom Defoirdt; Nico Boon; Thomas H. MacRae; Patrick Sorgeloos; Peter Bossier

    2009-01-01

    Feeding of bacterially encapsulated heat shock proteins (Hsps) to\\u000a invertebrates is a novel way to limit Vibrio infection. As an example,\\u000a ingestion of Escherichia coli overproducing prokaryotic Hsps\\u000a significantly improves survival of gnotobiotically cultured Artemia\\u000a larvae upon challenge with pathogenic Vibrio campbellii. The\\u000a relationship between Hsp accumulation and enhanced resistance to\\u000a infection may involve DnaK, the prokaryotic equivalent to Hsp70,

  7. Occurrence of Vibrio and Salmonella species in mussels (Mytilus galloprovincialis) collected along the Moroccan Atlantic coast.

    PubMed

    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. Whole Transcriptome Profiling of Successful Immune Response to Vibrio Infections in the Oyster Crassostrea gigas by Digital Gene Expression Analysis

    PubMed Central

    de Lorgeril, Julien; Zenagui, Reda; Rosa, Rafael D.; Piquemal, David; Bachère, Evelyne

    2011-01-01

    The cultivated Pacific oyster Crassostrea gigas has suffered for decades large scale summer mortality phenomenon resulting from the interaction between the environment parameters, the oyster physiological and/or genetic status and the presence of pathogenic microorganisms including Vibrio species. To obtain a general picture of the molecular mechanisms implicated in C. gigas immune responsiveness to circumvent Vibrio infections, we have developed the first deep sequencing study of the transcriptome of hemocytes, the immunocompetent cells. Using Digital Gene Expression (DGE), we generated a transcript catalog of up-regulated genes from oysters surviving infection with virulent Vibrio strains (Vibrio splendidus LGP32 and V. aestuarianus LPi 02/41) compared to an avirulent one, V. tasmaniensis LMG 20012T. For that an original experimental infection protocol was developed in which only animals that were able to survive infections were considered for the DGE approach. We report the identification of cellular and immune functions that characterize the oyster capability to survive pathogenic Vibrio infections. Functional annotations highlight genes related to signal transduction of immune response, cell adhesion and communication as well as cellular processes and defence mechanisms of phagocytosis, actin cytosqueleton reorganization, cell trafficking and autophagy, but also antioxidant and anti-apoptotic reactions. In addition, quantitative PCR analysis reveals the first identification of pathogen-specific signatures in oyster gene regulation, which opens the way for in depth molecular studies of oyster-pathogen interaction and pathogenesis. This work is a prerequisite for the identification of those physiological traits controlling oyster capacity to survive a Vibrio infection and, subsequently, for a better understanding of the phenomenon of summer mortality. PMID:21829707

  9. Adaptation to enemy shifts: rapid resistance evolution to local Vibrio spp. in invasive Pacific oysters.

    PubMed

    Wendling, Carolin C; Wegner, K Mathias

    2015-04-01

    One hypothesis for the success of invasive species is reduced pathogen burden, resulting from a release from infections or high immunological fitness of invaders. Despite strong selection exerted on the host, the evolutionary response of invaders to newly acquired pathogens has rarely been considered. The two independent and genetically distinct invasions of the Pacific oyster Crassostrea gigas into the North Sea represent an ideal model system to study fast evolutionary responses of invasive populations. By exposing both invasion sources to ubiquitous and phylogenetically diverse pathogens (Vibrio spp.), we demonstrate that within a few generations hosts adapted to newly encountered pathogen communities. However, local adaptation only became apparent in selective environments, i.e. at elevated temperatures reflecting patterns of disease outbreaks in natural populations. Resistance against sympatric and allopatric Vibrio spp. strains was dominantly inherited in crosses between both invasion sources, resulting in an overall higher resistance of admixed individuals than pure lines. Therefore, we suggest that a simple genetic resistance mechanism of the host is matched to a common virulence mechanism shared by local Vibrio strains. This combination might have facilitated a fast evolutionary response that can explain another dimension of why invasive species can be so successful in newly invaded ranges. PMID:25716784

  10. The multiple identities of Vibrio parahaemolyticus.

    PubMed

    McCarter, L

    1999-08-01

    Vibrio parahaemolyticus is a ubiquitous marine bacterium and human pathogen. The organism possesses multiple cell types appropriate for life under different circumstances. The swimmer cell, with a single polar flagellum, is adapted to life in liquid environments. The polar flagellum is powered by the sodium motive force and can propel the bacterium at fast speeds. The swarmer cell, propelled by many proton-powered lateral flagella, can move through highly viscous environments, colonize surfaces, and form multicellular communities which sometimes display highly periodic architecture. Signals that induce differentiation to the surface-adapted cell type are both physical and chemical in nature. Surface-induced gene expression may aid survival, whether attached to inanimate surfaces or in a host organism. Genetic rearrangements create additional phenotypic versatility, which is manifested as variable opaque and translucent colony morphotypes. Discovery that a LuxR homolog controls the opaque cell type implicates intercellular signaling as an additional survival strategy. The alternating identities of V. parahaemolyticus may play important roles in attachment and detachment, how bacterial populations adapt to growth on surfaces, form structured communities, and develop biofilms. PMID:10941784

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

    PubMed Central

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

    2013-01-01

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

  12. The effect of ? radiation on the expression of the virulence genes of Salmonella typhimurium and Vibrio spp

    Microsoft Academic Search

    Sangyong Lim; Jinwoo Jung; Dongho Kim

    2007-01-01

    The principle benefit of food irradiation is the reduction of food-borne bacteria in food products. However, the microbiological safety with respect to increased virulence of surviving pathogens after irradiation remains an important issue with regard to the effectiveness of food irradiation. In this study, the transcriptional changes of virulence genes of Salmonella and Vibrio spp. after ? radiation were investigated

  13. Le Roux et al, 2002 (Aquat Living Resour 15, 251258) Comparative analysis of Vibrio splendidus-related strains isolated

    E-print Network

    Paris-Sud XI, Université de

    -related strains isolated during Crassostrea gigas mortality events Frédérique Le Roux a,*, Mélanie Gay aDNA, rpoD, and gyrB genes. Genomic similarities were confirmed by DNA/DNA hybridization. Only one strain is likely to reveal genes involved in pathogenicity. Résumé Comparaison de souches apparentées à Vibrio

  14. Identification of a Protein Biomarker Unique to the Pandemic O3:K6 Clone of Vibrio parahaemolyticus

    Microsoft Academic Search

    Tracie L. Williams; Steven M. Musser; Jessica L. Nordstrom; Angelo DePaola; Steven R. Monday

    2004-01-01

    The present method of characterizing Vibrio parahaemolyticus strains involves serotyping or detection meth- ods based on assessment of the presence or absence of genes thought to be markers of an organism's patho- genicity. It is unclear whether these assays detect all pathogenic V. parahaemolyticus strains since a clear cor- relation between the presence of a particular gene and the organism's

  15. Identification of an Antagonistic Probiotic Combination Protecting Ornate Spiny Lobster (Panulirus ornatus) Larvae against Vibrio owensii Infection

    Microsoft Academic Search

    Evan F. Goulden; Michael R. Hall; Lily L. Pereg; Lone Høj

    2012-01-01

    Vibrio owensii DY05 is a serious pathogen causing epizootics in the larviculture of ornate spiny lobster Panulirus ornatus. In the present study a multi-tiered probiotic screening strategy was used to identify a probiotic combination capable of protecting P. ornatus larvae (phyllosomas) from experimental V. owensii DY05 infection. From a pool of more than 500 marine bacterial isolates, 91 showed definitive

  16. Role of sodium bioenergetics in Vibrio cholerae.

    PubMed

    Häse, C C; Barquera, B

    2001-05-01

    The ability of the bacterium to use sodium in bioenergetic processes appears to play a key role in both the environmental and pathogenic phases of Vibrio cholerae. Aquatic environments, including fresh, brackish, and coastal waters, are an important factor in the transmission of cholera and an autochthonous source. The organism is considered to be halophilic and has a strict requirement for Na(+) for growth. Furthermore, expression of motility and virulence factors of V. cholerae is intimately linked to sodium bioenergetics and to each other. Several lines of evidence indicated that the activity of the flagellum of V. cholerae might have an impact on virulence gene regulation. As the V. cholerae flagellum is sodium-driven and the Na(+)-NQR enzyme is known to create a sodium motive force across the bacterial membrane, it was recently suggested that the increased toxT expression observed in a nqr-negative strain is mediated by affecting flagella activity. It was suggested that the V. cholerae flagellum might respond to changes in membrane potential and the resulting changes in flagellar rotation might serve as a signal for virulence gene expression. However, we recently demonstrated that although the flagellum of V. cholerae is not required for the effects of ionophores on virulence gene expression, changes in the sodium chemical potential are sensed and thus alternative mechanisms, perhaps involving the TcpP/H proteins, for the detection of these conditions must exist. Analyzing the underlying mechanisms by which bacteria respond to changes in the environment, such as their ability to monitor the level of membrane potential, will probably reveal complex interplays between basic physiological processes and virulence factor expression in a variety of pathogenic species. PMID:11248198

  17. Radiofrequency transmission line for bioluminescent Vibrio sp. irradiation

    NASA Astrophysics Data System (ADS)

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

    2012-07-01

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

  18. Role of Vibrio cholerae O139 Surface Polysaccharides in Intestinal Colonization

    Microsoft Academic Search

    Jutta Nesper; Stefan Schild; Crystal M. Lauriano; Anita Kraiss; Karl E. Klose; Joachim Reidl

    2002-01-01

    Received 8 May 2002\\/Returned for modification 8 July 2002\\/Accepted 5 August 2002 Since the first occurrence of O139 Vibrio cholerae as a cause of cholera epidemics, this serogroup has been investigated intensively, and it has been found that its pathogenicity is comparable to that of O1 El Tor strains. O139 isolates express a thin capsule, composed of a polymer of

  19. Toxicity of the extracellular products of Vibrio damsela isolated from diseased fish

    Microsoft Academic Search

    Belén Fouz; Juan L. Barja; Carmen Amaro; Carmen Rivas; Alicia E. Toranzo

    1993-01-01

    In this work we analyzed the pathogenic in vivo and in vitro activities for both fish and mammals of extracellular products (ECP) of several isolates ofVibrio damsela implicated in disease problems in marine culture. The ECP from all the strains were strongly lethal for fish (LD50 ranging from 0.06 to 3.7 µg protein\\/g fish) and mice (LD50 ranging from 0.02

  20. The Global Regulator ArcA Modulates Expression of Virulence Factors in Vibrio cholerae

    Microsoft Academic Search

    Nilanjan Sengupta; Kalidas Paul; Rukhsana Chowdhury

    2003-01-01

    A Vibrio cholerae arcA mutant was constructed and used to examine the role of the global anaerobiosis response regulator ArcA in the expression of virulence factors in this important human pathogen. In V. cholerae, expression of the major virulence factors cholera toxin (CT) and toxin-coregulated pilus (TCP) is regulated by the transcriptional activator ToxT. toxT expression, in turn, is controlled

  1. Identification of Proteins Secreted via Vibrio parahaemolyticus Type III Secretion System 1

    Microsoft Academic Search

    Takahiro Ono; Kwon-Sam Park; Mayumi Ueta; Tetsuya Iida; Takeshi Honda

    2006-01-01

    Vibrio parahaemolyticus, a gram-negative marine bacterium, is an important pathogen causing food-borne gas- troenteritis or septicemia. Recent genome sequencing of the RIMD2210633 strain (a Kanagawa phenomenon- positive clinical isolate of serotype O3:K6) revealed that the strain has two sets of gene clusters that encode the type III secretion system (TTSS) apparatus. The first cluster, TTSS1, is located on the large

  2. Draft Whole-Genome Sequences of 14 Vibrio parahaemolyticus Clinical Isolates with an Ambiguous K Serogroup.

    PubMed

    Ronholm, J; Petronella, N; Kenwell, R; Banerjee, S

    2015-01-01

    Vibrio parahaemolyticus is a bacterial pathogen responsible for mild to severe gastroenteritis, wound infections, and septicemia resulting from the ingestion or handling of raw or undercooked contaminated seafood. Here, we report the draft whole-genome sequences and annotations of 14 Canadian V. parahaemolyticus clinical isolates that were serologically identified as K group II using polyvalent antisera but were not specifically K serogrouped using monovalent antisera. PMID:25838480

  3. Development of a sensitive and specific biosensor assay to detect Vibrio vulnificus in estuarine waters

    Microsoft Academic Search

    Robert M Ulrich

    2004-01-01

    Biosensor development has the potential to meet the need for rapid, sensitive, and specific detection of pathogenic bacteria from natural sources. An antibody-based fiber-optic biosensor assay to detect low levels of Vibrio vulnificus in estuarine waters following an enrichment step was developed. The principle of the sensor is based on an immuno-sandwich assay where an anti-V. vulnificus polyclonal capture antibody

  4. Survival and viability of nonculturable Escherichia coli and Vibrio cholerae in the estuarine and marine environment

    Microsoft Academic Search

    Huai-Shu Xu; N. Roberts; F. L. Singleton; R. W. Attwell; D. J. Grimes; R. R. Colwell

    1982-01-01

    Plating methods for estimating survival of indicator organisms, such asEscherichia coli, and water-borne pathogens includingVibrio cholerae, have severe limitations when used to estimate viable populations of these organisms in the aquatic environment. By combining the methods of immunofluorescent microscopy, acridine orange direct counting, and direct viable counting, with culture methods such as indirect enumeration by most probable number (MPN) estimation

  5. Quorum-sensing regulators control virulence gene expression in Vibrio cholerae

    Microsoft Academic Search

    Jun Zhu; Melissa B. Miller; Russell E. Vance; Michelle Dziejman; John J. Mekalanos

    2002-01-01

    The production of virulence factors including cholera toxin and the toxin-coregulated pilus in the human pathogen Vibrio cholerae is strongly influenced by environmental conditions. The well-characterized ToxR signal transduction cascade is responsible for sensing and integrating the environmental information and controlling the virulence regulon. We show here that, in addition to the known components of the ToxR signaling circuit, quorum-sensing

  6. Siderophore-Mediated Iron Acquisition Mechanisms in Vibrio vulnificusBiotype 2

    Microsoft Academic Search

    ELENA G. BIOSCA; BELEN FOUZ; ELENA ALCAIDE; ANDCARMEN AMARO

    1996-01-01

    Vibrio vulnificus biotype 2 is a primary pathogen for eels and, as has recently been suggested, an opportu- nisticpathogenforhumans.InthisstudywehaveinvestigatedtheabilityofV.vulnificusbiotype2toobtainiron by siderophore-mediated mechanisms and evaluated the importance of free iron in vibriosis. The virulence degree for eels was dependent on iron availability from hostfluids, as was revealed by a reduction in the 50% lethal dose for iron-overloaded eels. This biotype produced

  7. Effects of Green Tea Extract on Reducing Vibrio parahaemolyticus and Increasing Shelf Life of Oyster Meats

    Microsoft Academic Search

    Dunyu Xi; Chengchu Liu; Yi-Cheng Su

    This study investigated effects of tea extract on growth of pathogenic Vibrio parahaemolyticus and potential utilization in post-harvest treatment to extend shelf life of Pacific oysters (Crassostrea gigas). Longjing Tea, which exhibited strong bactericidal activity against V. parahaemolyticus, was selected to use in this study. Tea extract containing equal or higher than 4.6 g\\/l total phenolic contents (TPC) as gallic

  8. The effect of storage time on Vibrio spp. and fecal indicator bacteria in an Isco autosampler.

    PubMed

    Ghazaleh, Maite N; Froelich, Brett A; Noble, Rachel T

    2014-09-01

    Monitoring concentrations of bacterial pathogens and indicators of fecal contamination in coastal and estuarine ecosystems is critical to reduce adverse effects to public health. During storm events, particularly hurricanes, floods, Nor'easters, and tropical cyclones, sampling of coastal and estuarine waters is not generally possible due to safety concerns. It is particularly important to monitor waters during these periods as it is at precisely these times that pathogenic bacteria such as Vibrio spp. and fecal indicator bacteria concentrations fluctuate, potentially posing significant risks to public health. Automated samplers, such as the Isco sampler, are commonly used to conduct remote sample collection. Remote sampling is employed during severe storm periods, thereby reducing risk to researchers. Water samples are then stored until conditions are safe enough to retrieve them, typically in less than 21h, to collect the samples. Concerns exist regarding potential "bottle effects", whereby containment of sample might result in altered results. While these effects are well documented in samples being held for 24h or more, there is little data on bottle effects occurring during the first 24h of containment, and less still on the specific effects related to this type of sampling regime. Estuarine water samples were collected in the fall of 2013, placed into an Isco autosampler and subsampled over time to determine the effects of storage within this type of autosampling device. Vibrio spp. and fecal indicator bacteria were quantified using replicated culture-based methods, including Enterolert™ and membrane filtration. The experiments demonstrated no significant impact of storage time when comparing concentrations of total Vibrio spp., Vibrio vulnificus, Vibrio parahaemolyticus, or Enterococcus spp. after storage compared to original concentrations. However, the findings also suggested that increased variability and growth can occur during the middle of the day. Therefore, if at all possible, analysis schedules should be modified to account for this variability, e.g. collection of samples after overnight storage should occur as early in the morning as practicable. PMID:25008356

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

    PubMed Central

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

    2013-01-01

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

  10. Molecular analysis of the emergence of pandemic Vibrio parahaemolyticus

    PubMed Central

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

    2008-01-01

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

  11. The effect of ? radiation on the expression of the virulence genes of Salmonella typhimurium and Vibrio spp.

    NASA Astrophysics Data System (ADS)

    Lim, Sangyong; Jung, Jinwoo; Kim, Dongho

    2007-11-01

    The principle benefit of food irradiation is the reduction of food-borne bacteria in food products. However, the microbiological safety with respect to increased virulence of surviving pathogens after irradiation remains an important issue with regard to the effectiveness of food irradiation. In this study, the transcriptional changes of virulence genes of Salmonella and Vibrio spp. after ? radiation were investigated by real-time PCR (RT-PCR). Samonella typhimurium is dependent upon the products of a large number of genes located within Salmonella pathogenicity islands (SPI) on the chromosome. The expressions of seven genes including four SPI genes, hilD, ssrB, pipB, and sopD, were measured at 1 h after 1 kGy irradiation. Compared with non-irradiated controls, the expression of hilD encoded within SPI1 and sopD encoding SPI1-related effector proteins was reduced about 4- and 16-fold, respectively. The expressions of Vibrio toxin genes, vvhA, ctxA, and tdh, were also monitored during the course of a growth cycle after re-inoculation of irradiated Vibrio spp. (0.5 and 1.0 kGy). The expressions of Vibrio toxin genes tested did not increase compared with non-irradiated counterparts. Results from this study indicate that ? radiation is much more likely to reduce the virulence gene expression of surviving pathogens.

  12. Detection, Isolation, and Identification of Vibrio cholerae from the Environment

    PubMed Central

    Huq, Anwar; Haley, Bradd J.; Taviani, Elisa; Chen, Arlene; Hasan, Nur A.; Colwell, Rita R.

    2012-01-01

    Recent molecular advances in microbiology have greatly improved the detection of bacterial pathogens in the environment. Improvement and a downward trend in the cost of molecular detection methods have contributed to increased frequency of detection of pathogenic microorganisms where traditional culture-based detection methods have failed. Culture methods also have been greatly improved and the confluence of the two suites of methods provides a powerful tool for detection, isolation, and characterization of pathogens. While molecular detection provides data on the presence and type of pathogens, culturing methods allow a researcher to preserve the organism of interest for “–omics” studies, such as genomic, metabolomic, secretomic, and transcriptomic analysis, which are rapidly becoming more affordable. This has yielded a clearer understanding of the ecology and epidemiology of microorganisms that cause disease. Specifically, important advances have been made over the past several years on isolation, detection, and identification of Vibrio cholerae, the causative agent of cholera in humans. In this unit, we present commonly accepted methods for isolation, detection, and characterization of V. cholerae, providing more extensive knowledge of the ecology and epidemiology of this organism. This unit has been fully revised and updated from the earlier unit (Huq, Grim et al. 2006) with the latest knowledge and additional information not previously included. We have also taken into account of cost of reagents and equipment that may be prohibitive for many researchers and have, therefore, included protocols for all laboratories, including those with limited resources, likely to be located in regions of cholera endemicity. PMID:22875567

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

    Microsoft Academic Search

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

    2010-01-01

    A 70-day growth trial was conducted with postlarvae 12 (PL12) Pacific white shrimp (Litopenaeus vannamei) to study the suitability of soybean meal and oil originating from a single-celled microorganism (thraustochytrid) as fishmeal and fish oil substitutes in practical diets for L. vannamei. The growth, survival rate and immune characteristics were evaluated. Seven experimental diets were designed with soybean meal used

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

    E-print Network

    Bulyk, Martha L.

    of these AIs requires three cognate two-component sensors that function in a phosphorelay cascade that impinges (AI). As cell population density increases, AIs accumulate and trigger population-wide changes and responds to at least three different AIs; HAI-1 (3-hydroxybutanoyl homoserine lactone) (Cao and Meighen

  15. The Extracellular Metalloprotease of Vibrio tubiashii Is a Major Virulence Factor for Pacific Oyster (Crassostrea gigas) Larvae?

    PubMed Central

    Hasegawa, Hiroaki; Lind, Erin J.; Boin, Markus A.; Häse, Claudia C.

    2008-01-01

    Vibrio tubiashii is a recently reemerging pathogen of larval bivalve mollusks, causing both toxigenic and invasive disease. Marine Vibrio spp. produce an array of extracellular products as potential pathogenicity factors. Culture supernatants of V. tubiashii have been shown to be toxic to oyster larvae and were reported to contain a metalloprotease and a cytolysin/hemolysin. However, the structural genes responsible for these proteins have yet to be identified, and it is uncertain which extracellular products play a role in pathogenicity. We investigated the effects of the metalloprotease and hemolysin secreted by V. tubiashii on its ability to kill Pacific oyster (Crassostrea gigas) larvae. While V. tubiashii supernatants treated with metalloprotease inhibitors severely reduced the toxicity to oyster larvae, inhibition of the hemolytic activity did not affect larval toxicity. We identified structural genes of V. tubiashii encoding a metalloprotease (vtpA) and a hemolysin (vthA). Sequence analyses revealed that VtpA shared high homology with metalloproteases from a variety of Vibrio species, while VthA showed high homology only to the cytolysin/hemolysin of Vibrio vulnificus. Compared to the wild-type strain, a VtpA mutant of V. tubiashii not only produced reduced amounts of protease but also showed decreased toxicity to C. gigas larvae. Vibrio cholerae strains carrying the vtpA or vthA gene successfully secreted the heterologous protein. Culture supernatants of V. cholerae carrying vtpA but not vthA were highly toxic to Pacific oyster larvae. Together, these results suggest that the V. tubiashii extracellular metalloprotease is important in its pathogenicity to C. gigas larvae. PMID:18456850

  16. 'Bioluminescent' Reporter Phage for the Detection of Category A Bacterial Pathogens

    PubMed Central

    Schofield, David A.; Molineux, Ian J.; Westwater, Caroline

    2011-01-01

    Yersinia pestis and Bacillus anthracis are Category A bacterial pathogens that are the causative agents of the plague and anthrax, respectively 1. Although the natural occurrence of both diseases' is now relatively rare, the possibility of terrorist groups using these pathogens as a bioweapon is real. Because of the disease's inherent communicability, rapid clinical course, and high mortality rate, it is critical that an outbreak be detected quickly. Therefore methodologies that provide rapid detection and diagnosis are essential to ensure immediate implementation of public health measures and activation of crisis management. Recombinant reporter phage may provide a rapid and specific approach for the detection of Y. pestis and B. anthracis. The Centers for Disease Control and Prevention currently use the classical phage lysis assays for the confirmed identification of these bacterial pathogens 2-4. These assays take advantage of naturally occurring phage which are specific and lytic for their bacterial hosts. After overnight growth of the cultivated bacterium in the presence of the specific phage, the formation of plaques (bacterial lysis) provides a positive identification of the bacterial target. Although these assays are robust, they suffer from three shortcomings: 1) they are laboratory based; 2) they require bacterial isolation and cultivation from the suspected sample, and 3) they take 24-36 h to complete. To address these issues, recombinant "light-tagged" reporter phage were genetically engineered by integrating the Vibrio harveyi luxAB genes into the genome of Y. pestis and B. anthracis specific phage 5-8. The resulting luxAB reporter phage were able to detect their specific target by rapidly (within minutes) and sensitively conferring a bioluminescent phenotype to recipient cells. Importantly, detection was obtained either with cultivated recipient cells or with mock-infected clinical specimens 7. For demonstration purposes, here we describe the method for the phage-mediated detection of a known Y. pestis isolate using a luxAB reporter phage constructed from the CDC plague diagnostic phage ?A1122 6,7 (Figure 1). A similar method, with minor modifications (e.g. change in growth temperature and media), may be used for the detection of B. anthracis isolates using the B. anthracis reporter phage W?::luxAB8. The method describes the phage-mediated transduction of a biolumescent phenotype to cultivated Y. pestis cells which are subsequently measured using a microplate luminometer. The major advantages of this method over the traditional phage lysis assays is the ease of use, the rapid results, and the ability to test multiple samples simultaneously in a 96-well microtiter plate format. Figure 1. Detection schematic. The phage are mixed with the sample, the phage infects the cell, luxAB are expressed, and the cell bioluminesces. Sample processing is not necessary; the phage and cells are mixed and subsequently measured for light. PMID:21775956

  17. Climate anomalies and the increasing risk of Vibrio parahaemolyticus and Vibrio vulnificus illnesses

    Microsoft Academic Search

    Jaime Martinez-Urtaza; John C. Bowers; Joaquin Trinanes; Angelo DePaola

    2010-01-01

    We examined the potential influence of climate anomalies in expanding the geographical and seasonal range of seafood-borne illnesses from Vibrio parahaemolyticus and Vibrio vulnificus. Archived climate data from areas of implicated seafood production were obtained from various sources, including in situ monitoring devices and satellite imagery. The geographical expansion of V. parahaemolyticus outbreaks into Peru and Alaska corresponded closely with

  18. A double WAP domain-containing protein PmDWD from the black tiger shrimp Penaeus monodon is involved in the controlling of proteinase activities in lymphoid organ

    Microsoft Academic Search

    Pranisa Suthianthong; Naritsara Pulsook; Premruethai Supungul; Anchalee Tassanakajon; Vichien Rimphanitchayakit

    2011-01-01

    A homolog of mammalian secretory leucocyte proteinase inhibitor or SLPI known as a double WAP domain (DWD) protein has been found in penaeid shrimp and believed to play an important role in innate immune system of the shrimp. The PmDWD identified from the Penaeus monodon EST database was investigated for its expression under pathogen infection. Infections by Vibrio harveyi and

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

    PubMed

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

    2007-10-23

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

  20. Gene cloning and prokaryotic expression of recombinant flagellin A from Vibrio parahaemolyticus

    NASA Astrophysics Data System (ADS)

    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.

  1. Draft Genome Sequences of Six Strains of Vibrio parahaemolyticus Isolated from Early Mortality Syndrome/Acute Hepatopancreatic Necrosis Disease Shrimp in Thailand

    PubMed Central

    Kondo, Hidehiro; Tinwongger, Sasiwipa; Proespraiwong, Porranee; Mavichak, Rapeepat; Unajak, Sasimanas; Nozaki, Reiko

    2014-01-01

    Some strains of Vibrio parahaemolyticus cause acute hepatopancreatic necrosis disease (AHPND) in shrimp. We sequenced 3 AHPND and 3 non-AHPND strains and found that all of them lacked the pathogenicity island relevant to human infection. A unique sequence encoding a type IV pilus/type IV secretion system was found in 3 AHPND strains. PMID:24723705

  2. Modified a colony forming unit microbial adherence to hydrocarbons assay and evaluated cell surface hydrophobicity and biofilm production of Vibrio scophthalmi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vibrio scophthalmi has been considered as an opportunistic pathogen of the flat fish. There is little information available on V. scophthalmi adhesion to the host, an important step in the initial infection process. The objectives of this study were to (1) develop a modified Microbial Adherence to H...

  3. Draft Genome Sequences of Two Vibrionaceae Species, Vibrio ponticus C121 and Photobacterium aphoticum C119, Isolated as Coral Reef Microbiota

    PubMed Central

    Al-saari, Nurhidayu; Meirelles, Pedro Milet; Mino, Sayaka; Suda, Wataru; Oshima, Kenshiro; Hattori, Masahira; Ohkuma, Moriya; Thompson, Fabiano L.; Gomez-Gil, Bruno; Sawabe, Toko

    2014-01-01

    Here, the draft genome sequences of two Vibrionaceae, Vibrio ponticus C121 and Photobacterium aphoticum C119, which were isolated from the coral reef vicinity in Okinawa, Japan, are reported. The genome provides further insight into the genomic plasticity, biocomplexity, and ecophysiology, including pathogenicity and evolution, of these genera. PMID:25359913

  4. Identification and expression of immune-related genes in hemocytes of soft-shell clams, Mya arenaria, challenged with Vibrio splendidus

    Microsoft Academic Search

    Mebrahtu T. Araya; Frederick Markham; Dante R. Mateo; Patty McKenna; Gerry R. Johnson; Franck C. J. Berthe; Ahmed Siah

    2010-01-01

    Although the mollusc immune system has been studied at the cellular level, the response to pathogens at gene expression level has not been thoroughly investigated. This study aimed to investigate the early molecular response of hemocytes of soft-shell clams, Mya arenaria, to Vibrio splendidus strain LGP32 by identification of transcripts involved in immune defense. The Suppression Subtractive Hybridization (SSH) was

  5. Control of luminous Vibrio species in penaeid aquaculture ponds

    Microsoft Academic Search

    D. J. W Moriarty

    1998-01-01

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

  6. Genomic characterization of non-O1, non-O139 Vibrio cholerae reveals genes for a type III secretion system

    Microsoft Academic Search

    Michelle Dziejman; Davide Serruto; Vincent C. Tam; Derek Sturtevant; Pornphan Diraphat; Shah M. Faruque; M. Hasibur Rahman; John F. Heidelberg; Jeremy Decker; Li Li; Kate T. Montgomery; George Grills; Raju Kucherlapati; John J. Mekalanos

    2005-01-01

    Non-O1, non-O139 Vibrio cholerae can cause gastroenteritis and extraintestinal infections, but, unlike O1 and O139 strains of V. cholerae, little is known about the virulence gene content of non-O1, non-O139 strains and their phylogenetic relationship to other pathogenic V. cholerae. Comparative genomic microarray analysis of four pathogenic non-O1, non-O139 strains indicates that these strains are quite divergent from O1 and

  7. Differential in vivo response of soft-shell clam hemocytes against two strains of Vibrio splendidus: Changes in cell structure, numbers and adherence

    Microsoft Academic Search

    Dante R. Mateo; Ahmed Siah; Mebrahtu T. Araya; Franck C. J. Berthe; Gerry R. Johnson; Spencer J. Greenwood

    2009-01-01

    Host–pathogen interaction models in aquatic species are useful tools for understanding the pathogenicity of diseases in cultured and wild populations. In this study we report the differential in vivo response of soft-shell clam (Mya arenaria) hemocytes against two strains of Vibrio splendidus. Responses were measured 24h after injecting into the posterior adductor muscle either an endemic wild-type strain (7SHRW) or

  8. Dietary administration of sodium alginate enhances the immune ability of white shrimp Litopenaeus vannamei and its resistance against Vibrio alginolyticus

    Microsoft Academic Search

    Winton Cheng; Chun-Hung Liu; Ching-Ming Kuo; Jiann-Chu Chen

    2005-01-01

    Haemocyte count, phenoloxidase activity, respiratory burst (release of superoxide anion), superoxide dismutase (SOD) activity, glutathione peroxidase (GPX) activity, phagocytic activity and clearance efficiency to the pathogen Vibrio alginolyticus were measured in white shrimp Litopenaeus vannamei juveniles (12.3±1.2g) which had been fed diets containing sodium alginate at 0.5, 1.0, 2.0gkg?1 after five months. L. vannamei fed a diet containing 2.0gkg?1 sodium

  9. The immune stimulatory effect of sodium alginate on the white shrimp Litopenaeus vannamei and its resistance against Vibrio alginolyticus

    Microsoft Academic Search

    Winton Cheng; Chun-Hung Liu; Su-Tuen Yeh; Jiann-Chu Chen

    2004-01-01

    The total haemocyte count (THC), differential haemocyte count (DHC), phenoloxidase activity, respiratory burst (release of superoxide anion), superoxide dismutase activity, phagocytic activity and clearance efficiency to the pathogen Vibrio alginolyticus were measured when the white shrimp Litopenaeus vannamei (9.4–11.3 g) were injected individually with sodium alginate at 10, 20 or 50 ?g g?1. No significant differences in THC, DHC and

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

    Microsoft Academic Search

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

    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

  11. Viable but non-culturable Vibrio cholerae O1 revert to a cultivable state in the human intestine

    Microsoft Academic Search

    R. R. Colwell; P. Brayton; D. Herrington; B. Tall; A. Huq; M. M. Levine

    1996-01-01

    Vibrio cholerae O1 can enter a state in which they remain viable but are non-culturable. Presumably, such bacteria can be pathogenic if they retain the capacity to proliferate in the human intestine following ingestion. Two groups of volunteeers were given inocula containing viable but non-culturable V. cholerae O1 of the attenuated vaccine strain CVD 101 (viable CVD 101 organisms readily

  12. Antibiotic-Resistant Vibrios in Farmed Shrimp

    PubMed Central

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

    2015-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  14. Prevalence and molecular characteristics of Vibrio spp. isolated from preharvest shrimp of the North Western Province of Sri Lanka.

    PubMed

    Koralage, Madura Sanjeevani Gonsal; Alter, Thomas; Pichpol, Duangporn; Strauch, Eckhard; Zessin, Karl-Hans; Huehn, Stephan

    2012-10-01

    This study investigated the prevalence and molecular characteristics of Vibrio spp. in farmed shrimp (Penaeus monodon) in Sri Lanka. A total of 170 shrimp samples (100 g of whole shrimp each) taken from individual ponds from 54 farms were collected 1 week prior to harvest from the North Western Province of Sri Lanka. Overall, 98.1% of the farms and 95.1% of the ponds were positive for Vibrio spp. in shrimp; at the pond level, V. parahaemolyticus (91.2%) was most common, followed by V. alginolyticus (18.8%), V. cholerae non-O1/non-O139 (4.1%), and V. vulnificus (2.4%). Multiple Vibrio spp. were detected in 20.6% of the ponds. None of the V. parahaemolyticus isolates (n = 419) were positive for the virulence-associated tdh (thermostable direct hemolysin) and trh (TDH-related hemolysin) genes. V. cholerae was confirmed by the presence of ompW, and all isolates (n = 8) were negative for the cholera toxin (ctxA) gene. V. cholerae isolates were serogrouped by PCR and identified as V. cholerae non-O1/non-O139. All four V. vulnificus strains, isolated from different ponds of two geographical regions, showed pathogenic potential; they belonged to vcgC sequence type, type B 16S rRNA genotype and contained a pilF polymorphism associated with human pathogenicity. The results of this study revealed the ubiquitous nature of vibrios in farmed shrimp. To minimize the potential risk of Vibrio infections due to handling or consumption of raw or undercooked seafood products, good manufacturing practices as well as proper handling and processing should be addressed. PMID:23043835

  15. Uptake and depuration of the opaque and translucent morphotypes of Vibrio vulnificus, and the effects of oyster passage on virulence Absorption et purification des morphotypes opaque et translucide de Vibrio vulnificus, et effets du passage sur l'huître sur leur virulence

    Microsoft Academic Search

    TRUDI GROUBERT; JAMES D. OLIVER

    Vibrio vulnificus is an estuarine bacterium which is known to be a significant human pathogen. It occurs in high numbers in oysters and other molluscan shellfish, where it is part of the animals' normal flora. V. vulnificus occurs in two colony morphotypes ; the opaque, encapsulated variety is virulent, whereas the translucent, non encapsulated variety is avirulent. Studies were carried

  16. High-salt preadaptation of Vibrio parahaemolyticus enhances survival in response to lethal environmental stresses.

    PubMed

    Kalburge, Sai Siddarth; Whitaker, W Brian; Boyd, E Fidelma

    2014-02-01

    Adaptation to changing environmental conditions is an important strategy for survival of foodborne bacterial pathogens. Vibrio parahaemolyticus is a gram-negative seafoodborne enteric pathogen found in the marine environment both free living and associated with oysters. This pathogen is a moderate halophile, with optimal growth at 3% NaCl. Among the several stresses imposed upon enteric bacteria, acid stress is perhaps one of the most important. V. parahaemolyticus has a lysine decarboxylase system responsible for decarboxylation of lysine to the basic product cadaverine, an important acid stress response system in bacteria. Preadaptation to mild acid conditions, i.e., the acid tolerance response, enhances survival under lethal acid conditions. Because of the variety of conditions encountered by V. parahaemolyticus in the marine environment and in oyster postharvest facilities, we examined the nature of the V. parahaemolyticus acid tolerance response under high-salinity conditions. Short preadaptation to a 6% salt concentration increased survival of the wild-type strain but not that of a cadA mutant under lethal acid conditions. However, prolonged exposure to high salinity (16 h) increased survival of both the wild-type and the cadA mutant strains. This phenotype was not dependent on the stress response sigma factor RpoS. Although this preadaptation response is much more pronounced in V. parahaemolyticus, this characteristic is not limited to this species. Both Vibrio cholerae and Vibrio vulnificus also survive better under lethal acid stress conditions when preadapted to high-salinity conditions. High salt both protected the organism against acid stress and increased survival under -20°C cold stress conditions. High-salt adaptation of V. parahaemolyticus strains significantly increases survival under environmental stresses that would otherwise be lethal to these bacteria. PMID:24490918

  17. Prevalence of Vibrio parahaemolyticus in oyster and clam culturing environments in Taiwan.

    PubMed

    Yu, Wei-Ting; Jong, Koa-Jen; Lin, Yu-Ren; Tsai, Shing-en; Tey, Yao Hsien; Wong, Hin-chung

    2013-01-01

    Vibrio parahaemolyticus is the most prevalent gastroenteritis pathogen in Taiwan and some other Asian countries, and it frequently occurs in oysters and other seafood. This study monitors changes in the density of V. parahaemolyticus and environmental parameters in oyster and hard clam aquacultural environments in Taiwan. Water, sediment and shellfish samples were collected from five sampling sites in 2008-2010, and analyzed for environmental physiochemical parameters, numbers of indicator bacteria (total aerobic counts, total coliforms and fecal coliforms), Vibrio and V. parahaemolyticus present. The results for open oyster farms and hard clam ponds did not differ significantly. V. parahaemolyticus was detected in 77.5, 77.5, 70.8 and 68.8% of the water, sediment, oyster and clam samples, respectively. The densities of V. parahaemolyticus were significantly higher in shellfish than in sediment or water samples, with mean values of 1.33, 1.04 and -0.02 Log CFU/g, respectively. Among these five sampling sites, Shengang and Fangyuan yielded significantly different data from those obtained at the other three sites. As determined by linear multiple regression, V. parahaemolyticus density in water samples depended significantly on the precipitation and Vibrio count, while the V. parahaemolyticus density in the sediment or shellfish samples depended significantly on the salinity of the seawater. Among 1076 isolates examined, a total of three putative pathogenic isolates were identified from 2.5% of the examined samples, and these isolates exhibited hemolytic or urease activities and the presence of gene markers for tdh, trh, type III secretion system (T3SS) 1 (vcrD1) or T3SS2? (vcrD2). The results herein may facilitate the assessment of risk associated with this pathogen in Taiwan and other geographically similar regions. PMID:23290223

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

    PubMed Central

    Temperton, Ben; Thomas, Simon; Tait, Karen; Parry, Helen; Emery, Matt; Allen, Mike; Quinn, John; MacGrath, John; Gilbert, Jack

    2011-01-01

    Vibrio tubiashii NCIMB 1337 is a major and increasingly prevalent pathogen of bivalve mollusks, and shares a close phylogenetic relationship with both V. orientalis and V. coralliilyticus. It is a Gram-negative, curved rod-shaped bacterium, originally isolated from a moribund juvenile oyster, and is both oxidase and catalase positive. It is capable of growth under both aerobic and anaerobic conditions. Here we describe the features of this organism, together with the draft genome and annotation. The genome is 5,353,266 bp long, consisting of two chromosomes, and contains 4,864 protein-coding and 86 RNA genes. PMID:21677855

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

    SciTech Connect

    Temperton, B.; Thomas, S.; Tait, K.; Parry, H.; Emery, M.; Allen, M.; Quinn, J.; McGrath, J.; Gilbert, J. (CLS-GSB); (Plymouth Marine Lab.); (Queen's Univ.); (Univ. of Plymouth); (Univ. of Chicago)

    2011-01-01

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

  20. Structure of vulnibactin, a new polyamine-containing siderophore from Vibrio vulnificus

    Microsoft Academic Search

    Noriyuki Okujo; Miki Saito; Shigeo Yamamoto; Takashi Yoshida; Shinichi Miyoshi; Sumio Shinoda

    1994-01-01

    A new siderophore named vulnibactin has been isolated from low iron cultures of Vibrio vulnificus, a human pathogen. The structure was established as N-[3-(2,3-dihydroxybenzamido)propyl]-1,3-bis[2-(2-hydroxyphenyl)-trans-5-methyl-2-oxazoline-4-carboxamido]propane by a combination of acid hydrolysis, nuclear magnetic resonance spectroscopy and positive fast atom bombardment mass spectrometry. Vulnibactin is characterized as containing one residue of 2,3-dihydroxybenzoic acid as well as two residues of salicylic acid, both

  1. Daily variations in pathogenic bacterial populations in a monsoon influenced tropical environment.

    PubMed

    Khandeparker, Lidita; Anil, Arga Chandrashekar; Naik, Sneha D; Gaonkar, Chetan C

    2015-07-15

    Changing climatic conditions have influenced the monsoon pattern in recent years. Variations in bacterial population in one such tropical environment were observed everyday over two years and point out intra and inter annual changes driven by the intensity of rainfall. Vibrio spp. were abundant during the monsoon and so were faecal coliforms. Vibrio alginolyticus were negatively influenced by nitrate, whereas, silicate and rainfall positively influenced Vibrio parahaemolyticus numbers. It is also known that pathogenic bacteria are associated with the plankton. Changes in the abundance of plankton, which are governed mainly by environmental changes, could be responsible for variation in pathogenic bacterial abundance during monsoon, other than the land runoff due to precipitation and influx of fresh water. PMID:25956443

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

    PubMed Central

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

    1967-01-01

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

  3. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

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

  4. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

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

  5. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

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

  6. Comparison of fecal indicators with pathogenic bacteria and rotavirus in groundwater

    E-print Network

    van Geen, Alexander

    microorganisms (E. coli, total coliform, F+RNA coli- phage, Bacteroides and human-associated Bacteroides the largest proportion of tubewells (40%), followed by Shigella (10%), Vibrio (10%), and pathogenic E. coli (8, but annually averaged monthly measurements of culturable E. coli did improve prediction for total bacterial

  7. Abundance of Vibrio cholerae, V. vulnificus, and V. parahaemolyticus in Oysters (Crassostrea virginica) and Clams (Mercenaria mercenaria) from Long Island Sound

    PubMed Central

    Lüdeke, Catharina H. M.; Bowers, John C.; DeRosia-Banick, Kristin; Carey, David H.; Hastback, William

    2014-01-01

    Vibriosis is a leading cause of seafood-associated morbidity and mortality in the United States. Typically associated with consumption of raw or undercooked oysters, vibriosis associated with clam consumption is increasingly being reported. However, little is known about the prevalence of Vibrio spp. in clams. The objective of this study was to compare the levels of Vibrio cholerae, Vibrio vulnificus, and Vibrio parahaemolyticus in oysters and clams harvested concurrently from Long Island Sound (LIS). Most probable number (MPN)–real-time PCR methods were used for enumeration of total V. cholerae, V. vulnificus, V. parahaemolyticus, and pathogenic (tdh+ and/or trh+) V. parahaemolyticus. V. cholerae was detected in 8.8% and 3.3% of oyster (n = 68) and clam (n = 30) samples, with levels up to 1.48 and 0.48 log MPN/g in oysters and clams, respectively. V. vulnificus was detected in 97% and 90% of oyster and clam samples, with median levels of 0.97 and ?0.08 log MPN/g, respectively. V. parahaemolyticus was detected in all samples, with median levels of 1.88 and 1.07 log MPN/g for oysters and clams, respectively. The differences between V. vulnificus and total and pathogenic V. parahaemolyticus levels in the two shellfish species were statistically significant (P < 0.001). These data indicate that V. vulnificus and total and pathogenic V. parahaemolyticus are more prevalent and are present at higher levels in oysters than in hard clams. Additionally, the data suggest differences in vibrio populations between shellfish harvested from different growing area waters within LIS. These results can be used to evaluate and refine illness mitigation strategies employed by risk managers and shellfish control authorities. PMID:25281373

  8. Nigribactin, a Novel Siderophore from Vibrio nigripulchritudo, Modulates Staphylococcus aureus Virulence Gene Expression

    PubMed Central

    Nielsen, Anita; Mansson, Maria; Wietz, Matthias; Varming, Anders N.; Phipps, Richard K.; Larsen, Thomas O.; Gram, Lone; Ingmer, Hanne

    2012-01-01

    Staphylococcus aureus is a serious human pathogen that employs a number of virulence factors as part of its pathogenesis. The purpose of the present study was to explore marine bacteria as a source of compounds that modulate virulence gene expression in S. aureus. During the global marine Galathea 3 expedition, a strain collection was established comprising bacteria that express antimicrobial activity against Vibrio anguillarum and/or Staphylococcus aureus. Within this collection we searched colony material, culture supernatants, and cell extracts for virulence modulating activity showing that 68 out of 83 marine bacteria (affiliated with the Vibrionaceae and Pseudoalteromonas sp.) influenced expression of S. aureus hla encoding ?-hemolysin toxin and/or spa encoding Protein A. The isolate that upon initial screening showed the highest degree of interference (crude ethyl acetate extract) was a Vibrio nigripulchritudo. Extraction, purification and structural elucidation revealed a novel siderophore, designated nigribactin, which induces spa transcription. The effect of nigribactin on spa expression is likely to be independent from its siderophore activity, as another potent siderophore, enterobactin, failed to influence S. aureus virulence gene expression. This study shows that marine microorganisms produce compounds with potential use in therapeutic strategies targeting virulence rather than viability of human pathogens. PMID:23203279

  9. Gene cloning and prokaryotic expression of recombinant outer membrane protein from Vibrio parahaemolyticus

    NASA Astrophysics Data System (ADS)

    Yuan, Ye; Wang, Xiuli; Guo, Sheping; Qiu, Xuemei

    2011-06-01

    Gram-negative Vibrio parahaemolyticus is a common pathogen in humans and marine animals. The outer membrane protein of bacteria plays an important role in the infection and pathogenicity to the host. Thus, the outer membrane proteins are an ideal target for vaccines. We amplified a complete outer membrane protein gene (ompW) 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 42.78 kDa. We purified the protein using Ni-NTA affinity chromatography and Anti-His antibody Western blotting, respectively. Our results provide a basis for future application of the OmpW protein as a vaccine candidate against infection by V. parahaemolyticus. In addition, the purified OmpW protein can be used for further functional and structural studies.

  10. Roles of thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH) in Vibrio parahaemolyticus

    PubMed Central

    Raghunath, Pendru

    2015-01-01

    Vibrio parahaemolyticus is the leading cause of seafood borne bacterial gastroenteritis in the world, often associated with the consumption of raw or undercooked seafood. However, not all strains of V. parahaemolyticus are pathogenic. The thermostable direct hemolysin (TDH) or TDH-related hemolysin (TRH) encoded by tdh and trh genes, respectively, are considered major virulence factors in V. parahaemolyticus. However, about 10% of clinical strains do not contain tdh and/or trh. Environmental isolates of V. parahaemolyticus lacking tdh and/or trh are also highly cytotoxic to human gastrointestinal cells. Even in the absence of these hemolysins, V. parahaemolyticus remains pathogenic indicating other virulence factors exist. This mini review aims at discussing the possible roles of tdh and trh genes in clinical and environmental isolates of V. parahaemolyticus. PMID:25657643

  11. Extended serotyping scheme for Vibrio cholerae

    Microsoft Academic Search

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

    1994-01-01

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

  12. Protective mechanism of curcumin against Vibrio vulnificus infection.

    PubMed

    Na, Hee Sam; Cha, Mi Hye; Oh, Dool-Ri; Cho, Cheong-Weon; Rhee, Joon Haeng; Kim, Young Ran

    2011-12-01

    Curcumin, a natural polyphenolic flavonoid extracted from the rhizome of Curcuma longa L., has many beneficial biological activities. However, there are relatively few reports of the effects of curcumin on pathogen infections. This study examined the effect of curcumin on a Vibrio vulnificus infection. The cytotoxicity of V. vulnificus to HeLa cells was significantly inhibited by curcumin (at 10 or 30 ?M). To further examine the inhibitory mechanism of curcumin against V. vulnificus-mediated cytotoxicity, the level of bacterial growth, bacterial motility, cell adhesion, RTX toxin expression and host cell reactions were evaluated. Curcumin inhibited V. vulnificus growth in HI broth. Curcumin inhibited both bacterial adhesion and RTX toxin binding to the host cells, which can be considered the major protective mechanisms for the decrease in V. vulnificus cytotoxicity. Curcumin also inhibited host cell rounding and actin aggregation, which are the early features of cell death caused by V. vulnificus. In addition, curcumin decreased the V. vulnificus-induced NF-?B translocation in HeLa cells. Finally, curcumin protected mice from V. vulnificus-induced septicemia. In conclusion, curcumin may be an alternative antimicrobial agent against fatal bacterial infections. PMID:22092562

  13. Origin of Vibrio parahaemolyticus O3:K6 pandemic clone.

    PubMed

    Chao, Guoxiang; Wang, Fang; Zhou, Xiaohui; Jiao, Xinan; Huang, Jinlin; Pan, Zhiming; Zhou, Liping; Qian, Xiaoqin

    2011-02-28

    O3:K6 pandemic clone of Vibrio parahaemolyticus has caused outbreaks in coastal countries since 1996. Mutilocus sequence typing (MLST) is an important tool to trace the source and analysis the evolution of bacteria. Based on MLST, the first pandemic clonal complex (CC) of V. parahaemolyticus has been confirmed. In this study, 57 pandemic strains, 27 pathogenic strains (tdh or trh positive) and 36 nonpathogenic strains isolated from China were analyzed with MLST. Forty-seven unique sequence types, one clonal complex (CC) and one doublet (D) were identified by eBURST and Mega4 analyses. CC corresponded to not only the known O3:K6 pandemic clone (including ST-3, ST-192, ST-227) but nonpathogenic clone (including ST-3, S-T2, ST-196, ST-220, ST-226). ST-3 was the founder of the complex. STs of the isolates were not inevitably associated with the presence or number of the accessory genes or the serotypes of the isolates. The ancestor strain of O3:K6 pandemic clone was originated from an environmental nonpathogenic O3:K6, ST-3 strain. The pandemic O3:K6 clone was developed from this strain in approximately 1996 by laterally transferring large fragments of genes including systematic functional genes and genomic islands. PMID:21316116

  14. Identification of an Antagonistic Probiotic Combination Protecting Ornate Spiny Lobster (Panulirus ornatus) Larvae against Vibrio owensii Infection

    PubMed Central

    Goulden, Evan F.; Hall, Michael R.; Pereg, Lily L.; Høj, Lone

    2012-01-01

    Vibrio owensii DY05 is a serious pathogen causing epizootics in the larviculture of ornate spiny lobster Panulirus ornatus. In the present study a multi-tiered probiotic screening strategy was used to identify a probiotic combination capable of protecting P. ornatus larvae (phyllosomas) from experimental V. owensii DY05 infection. From a pool of more than 500 marine bacterial isolates, 91 showed definitive in vitro antagonistic activity towards the pathogen. Antagonistic candidates were shortlisted based on phylogeny, strength of antagonistic activity, and isolate origin. Miniaturized assays used a green fluorescent protein labelled transconjugant of V. owensii DY05 to assess pathogen growth and biofilm formation in the presence of shortlisted candidates. This approach enabled rapid processing and selection of candidates to be tested in a phyllosoma infection model. When used in combination, strains Vibrio sp. PP05 and Pseudoalteromonas sp. PP107 significantly and reproducibly protected P. ornatus phyllosomas during vectored challenge with V. owensii DY05, with survival not differing significantly from unchallenged controls. The present study has shown the value of multispecies probiotic treatment and demonstrated that natural microbial communities associated with wild phyllosomas and zooplankton prey support antagonistic bacteria capable of in vivo suppression of a pathogen causing epizootics in phyllosoma culture systems. PMID:22792184

  15. An enzyme-linked immunosorbent assay for detection of Vibrio vulnificus biotype 2: development and field studies.

    PubMed Central

    Biosca, E G; Marco-Noales, E; Amaro, C; Alcaide, E

    1997-01-01

    Vibrio vulnificus biotype 2 is a primary eel pathogen which constitutes a lipopolysaccharide (LPS)-based homogeneous O serogroup within the species. In the present work, we have developed an enzyme-linked immunosorbent assay (ELISA) based on the specificity of LPS for the detection of this pathogen. The ELISA specificity was confirmed after testing 36 biotype 2 strains from laboratory cultures and environmental samples, 31 clinical and environmental biotype 1 isolates, and several strains of Vibrio, Aeromonas, and Yersinia species, including the fish pathogens V. anguillarum, V. furnissii, A. hydrophila, and Y. ruckerii. The detection limits for biotype 2 cells were around 10(4) to 10(5) cells/well, and the immunoassay was also able to detect cells in the nonculturable state. Artificially infected eels and environmental samples were analyzed, and the immunodetection was confirmed by cultural methods (isolation on selective and nonselective media before and after broth enrichment). With this methodology, V. vulnificus biotype 2 was successfully detected in infected eels and asymptomatic carriers, which suggests that eels can act as a reservoir for this pathogen. PMID:9023934

  16. Vibriophages Differentially Influence Biofilm Formation by Vibrio anguillarum Strains.

    PubMed

    Tan, Demeng; Dahl, Amalie; Middelboe, Mathias

    2015-07-01

    Vibrio anguillarum is an important pathogen in marine aquaculture, responsible for vibriosis. Bacteriophages can potentially be used to control bacterial pathogens; however, successful application of phages requires a detailed understanding of phage-host interactions under both free-living and surface-associated growth conditions. In this study, we explored in vitro phage-host interactions in two different strains of V. anguillarum (BA35 and PF430-3) during growth in microcolonies, biofilms, and free-living cells. Two vibriophages, ?H20 (Siphoviridae) and KVP40 (Myoviridae), had completely different effects on the biofilm development. Addition of phage ?H20 to strain BA35 showed efficient control of biofilm formation and density of free-living cells. The interactions between BA35 and ?H20 were thus characterized by a strong phage control of the phage-sensitive population and subsequent selection for phage-resistant mutants. Addition of phage KVP40 to strain PF430-3 resulted in increased biofilm development, especially during the early stage. Subsequent experiments in liquid cultures showed that addition of phage KVP40 stimulated the aggregation of host cells, which protected the cells against phage infection. By the formation of biofilms, strain PF430-3 created spatial refuges that protected the host from phage infection and allowed coexistence between phage-sensitive cells and lytic phage KVP40. Together, the results demonstrate highly variable phage protection mechanisms in two closely related V. anguillarum strains, thus emphasizing the challenges of using phages to control vibriosis in aquaculture and adding to the complex roles of phages as drivers of prokaryotic diversity and population dynamics. PMID:25911474

  17. Infaunal Burrows Are Enrichment Zones for Vibrio parahaemolyticus?†

    PubMed Central

    Gamble, Megan D.; Lovell, Charles R.

    2011-01-01

    Vibrio parahaemolyticus, a species that includes strains known to be pathogenic in humans, and other Vibrionaceae are common, naturally occurring bacteria in coastal environments. Understanding the ecology and transport of these organisms within estuarine systems is fundamental to predicting outbreaks of pathogenic strains. Infaunal burrows serve as conduits for increased transport of tidal waters and V. parahaemolyticus cells by providing large open channels from the sediment to salt marsh tidal creeks. An extensive seasonal study was conducted at the North Inlet Estuary in Georgetown, SC, to quantify Vibrionaceae and specifically V. parahaemolyticus bacteria in tidal water, fiddler crab (Uca pugilator, Uca pugnax) burrow water, and interstitial pore water. Numbers of V. parahaemolyticus bacteria were significantly higher within burrow waters (4,875 CFU ml?1) than in creek water (193 CFU ml?1) and interstitial pore water (128 CFU ml?1), demonstrating that infaunal burrows are sites of V. parahaemolyticus enrichment. A strong seasonal trend of increased abundances of Vibrionaceae and V. parahaemolyticus organisms during the warmer months of May through September was observed. Multilocus sequence typing (MLST) analysis of isolates presumed to be V. parahaemolyticus from creek water, pore water, and burrow water identified substantial strain-level genetic variability among V. parahaemolyticus bacteria. Analysis of carbon substrate utilization capabilities of organisms presumed to be V. parahaemolyticus also indicated physiological diversity within this clade, which helps to explain the broad distribution of these strains within the estuary. These burrows are “hot spots” of Vibrionaceae and V. parahaemolyticus cell numbers and strain diversity and represent an important microhabitat. PMID:21478307

  18. Extracellular and surface-bound biological activities of Vibrio fluvialis, Vibrio furnissii and related species

    Microsoft Academic Search

    D. C. Myatt; G. H. G. Davis

    1989-01-01

    Twenty-seven Vibrio strains were assessed for virulence-associated biological activities, including iron chelation, hydrolases, haemolysis and haemagglutination. All strains hydrolysed DNA, chitin, gelatin and casein, produced siderophores, and lysed red blood cells. All V. fluvialis, V. cholerae and V. mimicus strains exhibited diverse lipolytic activity distinct from more discriminate lipolysis by V. furnissii. V. furnissii manifested fibrin and mucin hydrolysis but

  19. Evaluating the Growth Potential of Pathogenic Bacteria in Water ? †

    PubMed Central

    Vital, Marius; Stucki, David; Egli, Thomas; Hammes, Frederik

    2010-01-01

    The degree to which a water sample can potentially support the growth of human pathogens was evaluated. For this purpose, a pathogen growth potential (PGP) bioassay was developed based on the principles of conventional assimilable organic carbon (AOC) determination, but using pure cultures of selected pathogenic bacteria (Escherichia coli O157, Vibrio cholerae, or Pseudomonas aeruginosa) as the inoculum. We evaluated 19 water samples collected after different treatment steps from two drinking water production plants and a wastewater treatment plant and from ozone-treated river water. Each pathogen was batch grown to stationary phase in sterile water samples, and the concentration of cells produced was measured using flow cytometry. In addition, the fraction of AOC consumed by each pathogen was estimated. Pathogen growth did not correlate with dissolved organic carbon (DOC) concentration and correlated only weakly with the concentration of AOC. Furthermore, the three pathogens never grew to the same final concentration in any water sample, and the relative ratio of the cultures to each other was unique in each sample. These results suggest that the extent of pathogen growth is affected not only by the concentration but also by the composition of AOC. Through this bioassay, PGP can be included as a parameter in water treatment system design, control, and operation. Additionally, a multilevel concept that integrates the results from the bioassay into the bigger framework of pathogen growth in water is discussed. The proposed approach provides a first step for including pathogen growth into microbial risk assessment. PMID:20693455

  20. The immune response of the white shrimp Litopenaeus vannamei and its susceptibility to Vibrio infection in relation with the moult cycle

    Microsoft Academic Search

    Chun-Hung Liu; Su-Tuen Yeh; Sha-Yen Cheng; Jiann-Chu Chen

    2004-01-01

    The white shrimp Litopenaeus vannamei (8.0–14.4 g) was examined for haemocyte count, phenoloxidase activity, respiratory burst (release of superoxide anion), phagocytic activity, and clearance efficiency to the pathogen Vibrio alginolyticus in relation with moult cycle (postmoult, A, B; intermoult, C; premoult, D0\\/D1D2\\/D3). Granular cells were the highest at C and D0\\/D1stage, and the lowest at A stage. Hyaline cells and

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

    PubMed

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

    2014-10-01

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

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

    PubMed Central

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

    2014-01-01

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

  3. Evidence that Vibrio vulnificus ahpC2 is essential for survival under high salinity by modulating intracellular level of ROS

    Microsoft Academic Search

    Myung Jin Koh; Hyun Sung Lee; Jee Eun Rhee; Sang Ho Choi

    2010-01-01

    Expression of ahpC2 encoding an alkyl hydroperoxide reductase of Vibrio vulnificus, a foodborne pathogen, was incrementally induced depending on NaCl concentrations in the culture. Growth of the ahpC2 mutant was significantly impaired with longer lag phase and lower growth rate when cultured under high salinity. ROS was\\u000a accumulated in V. vulnificus cells when stressed by exposure to high salinity, and

  4. Identification of amino acid residues required for ferric-anguibactin transport in the outer-membrane receptor FatA of Vibrio anguillarum

    Microsoft Academic Search

    Claudia S. Lopez; Alejandro F. Alice; Ranjan Chakraborty; Jorge H. Crosa

    2007-01-01

    Vibrio anguillarum 775 is a fish pathogen that causes a disease characterized by a fatal haemorrhagic septicaemia. It harbours the 65 kbp pJM1 plasmid, which encodes an iron sequestering system specific for the siderophore anguibactin and is essential for virulence. The genes involved in the biosynthesis of anguibactin are located on both the pJM1 plasmid and the chromosome. However, the

  5. The Effects of Storage Temperature on the Growth of Vibrio parahaemolyticus and Organoleptic Properties in Oysters

    PubMed Central

    Mudoh, Meshack Fon; Parveen, Salina; Schwarz, Jurgen; Rippen, Tom; Chaudhuri, Anish

    2014-01-01

    During harvesting and storage, microbial pathogens and natural spoilage flora may grow, negatively affecting the composition and texture of oysters and posing a potential health threat to susceptible consumers. A solution to these problems would mitigate associated damaging effects on the seafood industry. The purpose of this study was to investigate the effects of storage temperature on growth of vibrios as well as other microbial, sensory, and textural characteristics of post-harvest shellstock Eastern oysters (Crassostrea virginica). Oysters harvested from the Chesapeake Bay, Maryland, during summer months (June, July, and August, 2010) were subjected to three storage temperatures (5, 10, and 20°C) over a 10-day period. At selected time intervals (0, 1, 3, 7, and 10?days), two separate samples of six oysters each were homogenated and analyzed for pH, halophilic plate counts (HPC), total vibrios, and Vibrio parahaemolyticus (Vp). Oyster meats shucked after storage were also organoleptically evaluated (acceptability, appearance, and odor). Texture analysis was performed using a texture analyzer on meats shucked from oysters held under the same conditions. The pH of the oyster homogenates showed no consistent pattern with storage time and temperature. The HPC (4.5–9.4?log?CFU/g) were highest on day 7 at 20°C while olfactory acceptance reduced with time and increasing storage temperatures. The Vp counts increased over time from 3.5 to 7.5?log MPN/g by day 10. Loss of freshness as judged by appearance and odor was significant over time (p?

  6. The Effects of Storage Temperature on the Growth of Vibrio parahaemolyticus and Organoleptic Properties in Oysters.

    PubMed

    Mudoh, Meshack Fon; Parveen, Salina; Schwarz, Jurgen; Rippen, Tom; Chaudhuri, Anish

    2014-01-01

    During harvesting and storage, microbial pathogens and natural spoilage flora may grow, negatively affecting the composition and texture of oysters and posing a potential health threat to susceptible consumers. A solution to these problems would mitigate associated damaging effects on the seafood industry. The purpose of this study was to investigate the effects of storage temperature on growth of vibrios as well as other microbial, sensory, and textural characteristics of post-harvest shellstock Eastern oysters (Crassostrea virginica). Oysters harvested from the Chesapeake Bay, Maryland, during summer months (June, July, and August, 2010) were subjected to three storage temperatures (5, 10, and 20°C) over a 10-day period. At selected time intervals (0, 1, 3, 7, and 10?days), two separate samples of six oysters each were homogenated and analyzed for pH, halophilic plate counts (HPC), total vibrios, and Vibrio parahaemolyticus (Vp). Oyster meats shucked after storage were also organoleptically evaluated (acceptability, appearance, and odor). Texture analysis was performed using a texture analyzer on meats shucked from oysters held under the same conditions. The pH of the oyster homogenates showed no consistent pattern with storage time and temperature. The HPC (4.5-9.4?log?CFU/g) were highest on day 7 at 20°C while olfactory acceptance reduced with time and increasing storage temperatures. The Vp counts increased over time from 3.5 to 7.5?log MPN/g by day 10. Loss of freshness as judged by appearance and odor was significant over time (p?

  7. Molecular profiles and pathogen-induced transcriptional responses of prawn B cell lymphoma-2 related ovarian killer protein (BOK).

    PubMed

    Chaurasia, Mukesh Kumar; Palanisamy, Rajesh; Harikrishnan, Ramasamy; Arasu, Mariadhas Valan; Al-Dhabi, Naif Abdullah; Arockiaraj, Jesu

    2015-08-01

    In this study, we have reported a molecular characterization of the first B cell lymphoma-2 (BCL-2) related ovarian killer protein (BOK) from freshwater prawn Macrobrachium rosenbergii (Mr). BOK is a novel pro-apoptotic protein of the BCL-2 family that entails in mediating apoptosis to remove cancer cells. A cDNA sequence of MrBOK was identified from the prawn cDNA library and its full length was obtained by internal sequencing. The coding region of MrBOK yields a polypeptide of 291 amino acids. The analysis revealed that MrBOK contains a transmembrane helix at V(261)-L(283) and a putative BCL-2 family domain at V(144)-W(245). MrBOK also possessed four putative BCL-2 homology domains including BH1, BH2, BH3 and weak BH4. The BH3 contains 21 binding sites and among them five residues are highly conserved with the aligned BOK proteins. The homology analysis showed that MrBOK shared maximum similarity with the Caligus rogercresseyi BOK A. The topology of the phylogenetic tree was classified into nine sister groups which includes BOK, BAK, BAX, BAD, BCL-2, BCL-XL, NR13 and MCL members. The BOK protein group further sub-grouped into vertebrate and invertebrate BOK, wherein MrBOK located within insect monophyletic clad of invertebrate BOK. The secondary structural analysis showed that MrBOK contains 11 ?-helices (52.2%) which are connected over random coils (47.7%). The 3D structure of MrBOK showed three central helices (?6, ?7 and ?8) which formed the core of the protein and are flanked on one side by ?1, ?2 and ?3, and on the other side by ?4, ?5 and ?11. MrBOK mRNA is expressed most abundantly (P < 0.05) in ovary compared to other tissues taken for analysis. Hence ovary was selected to study the possible roles of MrBOK mRNA regulation upon bacterial (Aeromonas hydrophila and Vibrio harveyi) and viral [white spot syndrome virus (WSSV) and M. rosenbergii nodovirus] infection. During bacterial and viral infection, the highest MrBOK mRNA transcription was varied at different time points. In bacterial infected ovary tissue, the highest mRNA expression was at 24 h post-infection, whereas in viral infection, the expression was highest at 48 h post-infection. Thus we can conclude that MrBOK functions as an apoptotic protein in intracellular programmed cell-death pathway to counteract the anti-apoptotic proteins released by bacterial and viral pathogens at the time of infection. This is the first study that emphasizes the importance of BOK during bacterial and viral infection in crustacean. PMID:25982403

  8. Year round patchiness of Vibrio vulnificus within a temperate texas bay

    PubMed Central

    Shelli, F.; Gabriel, S.; Richard, L.

    2012-01-01

    Aims To investigate with high geographical resolution the small-scale spatial and temporal distribution of the pathogen Vibrio vulnificus throughout the water column in a temperate Texas bay where numerous V. vulnificus infections had been reported by the regional media the previous Summer. Methods and Results Surface and bottom water samples were collected from 19 sites between Apr 2005 and Oct 2006 from Matagorda Bay, TX. Physicochemical parameters were measured and V. vulnificus were analyzed using quantitative polymerase chain reaction (Q-PCR) as a means of overcoming constraints of traditional culturing techniques. V. vulnificus was detected through out the year, although it’s temporal and spatial distribution was patchy. V. vulnificus abundances at individual sites ranged from <10 to >1.1×103 cells mL?1. No statistically reliable predictive model related to the physicochemical parameters could be developed for this pathogen. Conclusions This study demonstrates year round detection of V. vulnificus while likely in the viable but non-culturable (VBNC) state during the winter months and emphasizes why physicochemical factors are insufficient metrics for robust regression modeling of this pathogen. Significance and Impact of the Study This study provides an effective new tool, Q-PCR, to study environmental distribution of V. vulnificus and that in light of the patchy distribution observed, new reliable approaches and a mechanistic understanding of pathogen ecology need to be considered to effectively model the aquatic distribution of V. vulnificus. PMID:22212214

  9. Pathogen intelligence

    PubMed Central

    Steinert, Michael

    2014-01-01

    Different species inhabit different sensory worlds and thus have evolved diverse means of processing information, learning and memory. In the escalated arms race with host defense, each pathogenic bacterium not only has evolved its individual cellular sensing and behavior, but also collective sensing, interbacterial communication, distributed information processing, joint decision making, dissociative behavior, and the phenotypic and genotypic heterogeneity necessary for epidemiologic success. Moreover, pathogenic populations take advantage of dormancy strategies and rapid evolutionary speed, which allow them to save co-generated intelligent traits in a collective genomic memory. This review discusses how these mechanisms add further levels of complexity to bacterial pathogenicity and transmission, and how mining for these mechanisms could help to develop new anti-infective strategies. PMID:24551600

  10. Pathogen intelligence.

    PubMed

    Steinert, Michael

    2014-01-01

    Different species inhabit different sensory worlds and thus have evolved diverse means of processing information, learning and memory. In the escalated arms race with host defense, each pathogenic bacterium not only has evolved its individual cellular sensing and behavior, but also collective sensing, interbacterial communication, distributed information processing, joint decision making, dissociative behavior, and the phenotypic and genotypic heterogeneity necessary for epidemiologic success. Moreover, pathogenic populations take advantage of dormancy strategies and rapid evolutionary speed, which allow them to save co-generated intelligent traits in a collective genomic memory. This review discusses how these mechanisms add further levels of complexity to bacterial pathogenicity and transmission, and how mining for these mechanisms could help to develop new anti-infective strategies. PMID:24551600

  11. [Transmission of Vibrio cholerae. Possible role of the camel].

    PubMed

    Dodin, A; Chamoiseau, G; Lepers, J P; Chartier, C

    1986-01-01

    Choleraic vibrio uses the moving means that man discovers to his own use. Camels (passive and active vehicles of large quantity of crude water) were experimentally infected with a Vibrio (tox. +) and an Aeromonas (tox. +). Suckling young camels eliminate them for 6 days and grown-up camels for 25 days. This experience, associated with the discovery of Vibrio non 01 and Shigella in the caravan camel dungs, lead them to become a potential vector of spreading from one oasis to another. PMID:3096512

  12. Purification and characterization of Vibrio metschnikovii cytolysin.

    PubMed

    Miyake, M; Honda, T; Miwatani, T

    1988-04-01

    An extracellular cytolysin produced by Vibrio metschnikovii was purified by acid precipitation, phenyl-Sepharose CL-4B chromatography, and rechromatography on a phenyl-Sepharose CL-4B column and high-performance liquid chromatography on a Mono Q (anion-exchange) column. The purified cytolysin had a molecular weight of 50,000 and an isoelectric point of 5.1. It was inactivated by heating at 60 degrees C for 5 min and was inhibited by Zn2+, Cu2+, and high concentrations of cholesterol. Lysis of calf erythrocytes by cytolysin was temperature dependent and occurred only above 18 degrees C. Moreover, no lysis was observed at high concentrations of erythrocytes, suggesting that the cytolysin lyses erythrocytes by a multihit mechanism. This cytolysin had no immunological cross-reactivities with hemolysins from other Vibrio species tested, indicating that it is a new cytolysin. V. metschnikovii cytolysin lysed erythrocytes from several animal species (calf, rabbit, guinea pig, mouse, human, sheep, chicken, and horse) and cultured cells (Vero and Chinese hamster ovary), caused fluid accumulation in the intestines of infant mice, and increased vascular permeability in rabbit skin. PMID:3126150

  13. FIGURE 2. -Immunodiffusion comparison of Vibrio anguil-larum 775 and Vibrio sp. 1669. Wells I, 3, and 5 contain V. an-

    E-print Network

    . The center well contains rabbit anti-V. anguil- larum 775 serum. V anguillarum 775 in rabbit anti-Vibrio sp a vaccine containing antigens from both vibrios would be more protective than vac- cines containing antigens from only one of the TABLE 2. - Agglutinin titers of rabbit anti-Vibrio sp. 1669 serum unabsorbed

  14. The evaluation of four recent culture-based methods for the isolation and enumeration of Vibrio vulnificus bacteria from oyster meat.

    PubMed

    Froelich, Brett A; Weiss, Mary Jo; Noble, Rachel T

    2014-02-01

    The most common cause of seafood-borne death in the United States is the bacterium Vibrio vulnificus which can be concentrated into high numbers in the tissues of oysters or other shellfish. The ability to quickly, accurately, and inexpensively isolate living strains of this organism from oyster tissues is crucial for effective research on this pathogen. In this report, we evaluate four methods for isolating and quantifying V. vulnificus from oyster tissues, the solid media CPC+ (a refined version of cellobiose-polymyxin B-colistin medium), CHROMagar Vibrio, VVX (Vibrio vulnificus X-gal), and a method termed "Triple plating". Up to 1225 presumptive isolates were detected by each method, and 335 were subjected to molecular typing. The selectivity and sensitivity of each method was examined and VVX was found to be the most accurate method, with each of the other methods being recommended for task-specific uses. CHROMagar Vibrio is recommended for ease of use and relative accuracy, CPC+ is best used to differentiate between clinically associated and environmental strains. PMID:24355773

  15. Interspecific quorum sensing mediates the resuscitation of viable but nonculturable vibrios.

    PubMed

    Ayrapetyan, Mesrop; Williams, Tiffany C; Oliver, James D

    2014-04-01

    Entry and exit from dormancy are essential survival mechanisms utilized by microorganisms to cope with harsh environments. Many bacteria, including the opportunistic human pathogen Vibrio vulnificus, enter a form of dormancy known as the viable but nonculturable (VBNC) state. VBNC cells can resuscitate when suitable conditions arise, yet the molecular mechanisms facilitating resuscitation in most bacteria are not well understood. We discovered that bacterial cell-free supernatants (CFS) can awaken preexisting dormant vibrio populations within oysters and seawater, while CFS from a quorum sensing mutant was unable to produce the same resuscitative effect. Furthermore, the quorum sensing autoinducer AI-2 could induce resuscitation of VBNC V. vulnificus in vitro, and VBNC cells of a mutant unable to produce AI-2 were unable to resuscitate unless the cultures were supplemented with exogenous AI-2. The quorum sensing inhibitor cinnamaldehyde delayed the resuscitation of wild-type VBNC cells, confirming the importance of quorum sensing in resuscitation. By monitoring AI-2 production by VBNC cultures over time, we found quorum sensing signaling to be critical for the natural resuscitation process. This study provides new insights into the molecular mechanisms stimulating VBNC cell exit from dormancy, which has significant implications for microbial ecology and public health. PMID:24509922

  16. Modeling and forecasting the distribution of Vibrio vulnificus in Chesapeake Bay

    SciTech Connect

    Jacobs, John M.; Rhodes, M.; Brown, C. W.; Hood, Raleigh R.; Leight, A.; Long, Wen; Wood, R.

    2014-11-01

    The aim is to construct statistical models to predict the presence, abundance and potential virulence of Vibrio vulnificus in surface waters. A variety of statistical techniques were used in concert to identify water quality parameters associated with V. vulnificus presence, abundance and virulence markers in the interest of developing strong predictive models for use in regional oceanographic modeling systems. A suite of models are provided to represent the best model fit and alternatives using environmental variables that allow them to be put to immediate use in current ecological forecasting efforts. Conclusions: Environmental parameters such as temperature, salinity and turbidity are capable of accurately predicting abundance and distribution of V. vulnificus in Chesapeake Bay. Forcing these empirical models with output from ocean modeling systems allows for spatially explicit forecasts for up to 48 h in the future. This study uses one of the largest data sets compiled to model Vibrio in an estuary, enhances our understanding of environmental correlates with abundance, distribution and presence of potentially virulent strains and offers a method to forecast these pathogens that may be replicated in other regions.

  17. Interspecific Quorum Sensing Mediates the Resuscitation of Viable but Nonculturable Vibrios

    PubMed Central

    Ayrapetyan, Mesrop; Williams, Tiffany C.

    2014-01-01

    Entry and exit from dormancy are essential survival mechanisms utilized by microorganisms to cope with harsh environments. Many bacteria, including the opportunistic human pathogen Vibrio vulnificus, enter a form of dormancy known as the viable but nonculturable (VBNC) state. VBNC cells can resuscitate when suitable conditions arise, yet the molecular mechanisms facilitating resuscitation in most bacteria are not well understood. We discovered that bacterial cell-free supernatants (CFS) can awaken preexisting dormant vibrio populations within oysters and seawater, while CFS from a quorum sensing mutant was unable to produce the same resuscitative effect. Furthermore, the quorum sensing autoinducer AI-2 could induce resuscitation of VBNC V. vulnificus in vitro, and VBNC cells of a mutant unable to produce AI-2 were unable to resuscitate unless the cultures were supplemented with exogenous AI-2. The quorum sensing inhibitor cinnamaldehyde delayed the resuscitation of wild-type VBNC cells, confirming the importance of quorum sensing in resuscitation. By monitoring AI-2 production by VBNC cultures over time, we found quorum sensing signaling to be critical for the natural resuscitation process. This study provides new insights into the molecular mechanisms stimulating VBNC cell exit from dormancy, which has significant implications for microbial ecology and public health. PMID:24509922

  18. Mechanistic insights into filamentous phage integration in Vibrio cholerae

    PubMed Central

    Das, Bhabatosh

    2014-01-01

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

  19. Vibrio cholerae and Aeromonas: do they share a mutual host?

    PubMed

    Senderovich, Yigal; Gershtein, Yana; Halewa, Etti; Halpern, Malka

    2008-03-01

    Species of the genus Aeromonas are native inhabitants of aquatic environments and have recently been considered as an emergent human pathogen. It is estimated that aeromonads cause up to 13% of reported gastroenteritis cases in the United States. Although the autochthonous existence of Aeromonas in the aquatic environment has been established, its natural reservoir is as yet unknown. Chironomids are closely related to mosquitoes except they do not bite and they are the most widely distributed insects in freshwater. They infest drinking water systems in Israel and all over the world. Vibrio cholerae inhabit chironomids and are able to degrade their egg masses. The degradation of the egg masses is followed by failure of the eggs to hatch. In the current study, egg masses from a waste stabilization pond and a river in northern Israel were collected and cultured during a five-month period. Bacterial colonies were randomly chosen and checked for their egg mass degradation abilities. In addition to V. cholerae, most of the other isolates that had the ability to degrade the egg masses were identified as Aeromonas species, thus, demonstrating that Aeromonas species are natural inhabitants of chironomid egg masses. The following virulence-associated genes were detected in Aeromonas species that were isolated from chironomid egg masses: alt (78%); ahpB (76%); act/aerA/hlyA (65%); fla (59%); pla/lipH3/apl-1/lip (43%); and ast (2%). These findings indicate that the Aeromonas species inhabiting chironomid egg masses pose a potential health risk. Understanding the natural reservoir of Aeromonas will help to develop methods to monitor and control the bacteria in fresh and drinking water reservoirs and to better understand the relationships between chironomids, V. cholerae and Aeromonas populations. PMID:18317460

  20. Factors That Explain Excretion of Enteric Pathogens by Persons Without Diarrhea

    PubMed Central

    Levine, Myron M.; Robins-Browne, Roy M.

    2012-01-01

    Excretion of enteropathogens by subjects without diarrhea influences our appreciation of the role of these pathogens as etiologic agents. Characteristics of the pathogens and host and environmental factors help explain asymptomatic excretion of diarrheal pathogens by persons without diarrhea. After causing acute diarrhea followed by clinical recovery, some enteropathogens are excreted asymptomatically for many weeks. Thus, in a prevalence survey of persons without diarrhea, some may be excreting pathogens from diarrheal episodes experienced many weeks earlier. Volunteer challenges with Vibrio cholerae O1, enterotoxigenic Escherichia coli (ETEC), enteropathogenic E. coli, Campylobacter jejuni, and Giardia lamblia document heterogeneity among enteropathogen strains, with some inexplicably not eliciting diarrhea. The immune host may not manifest diarrhea following ingestion of a pathogen but may nevertheless asymptomatically excrete. Some human genotypes render them less susceptible to symptomatic or severe diarrheal infection with certain pathogens such as Vibrio cholerae O1 and norovirus. Pathogens in stools of individuals without diarrhea may reflect recent ingestion of inocula too small to cause disease in otherwise susceptible hosts or of animal pathogens (eg, bovine or porcine ETEC) that do not cause human illness. PMID:23169942

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

    E-print Network

    McFall-Ngai, Margaret

    Establishment of an animal­bacterial association: Recruiting symbiotic vibrios from the environment of being colonized by appropriate microbes, while discouraging colonization by nonspecific ones. One are specifically detected and me- tabolized by symbiotically competent bacteria in the family Rhizobiaceae

  2. Pathogenesis of Vibrio anguillarum in the channel catfish (Ictalurus punctatus) 

    E-print Network

    Jones, David Munson

    1976-01-01

    cholera. Similar pteridine compounds were shown to "powerfully inhibit the growth of ~Stre to- coccus faecalis" (11). Its use as an agent for identifying vibrios was first suggested by Shewan et al. (50). However, Merkel emphasized that salts interfere...

  3. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

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

  4. Effect of Mukerjee's group IV phage on El Tor vibrios*

    PubMed Central

    Monsur, K. A.; Rizvi, S. S. H.; Huq, M. I.; Benenson, A. S.

    1965-01-01

    El Tor vibrios are characterized by their insusceptibility to Mukerjee's group IV phage in routine test dilutions. This study shows that group IV phage in sufficient titre will produce, on lawns of El Tor vibrios, clearing resembling phage lysis. However, when the phage is mixed with El Tor cultures, a fall occurs in the viable count of both bacteria and phage. Darkfield microscopy shows that the bacteria lose their motility; measurement of the mixture's optical density indicates that bacterial lysis does occur. Evidence to date provides no indication that group IV phage undergoes multiplication in the El Tor vibrios tested, all of which were isolated during several recent outbreaks of cholera. Because of the marked difference in its behaviour towards them, phage IV is valuable in differentiating true cholera from El Tor vibrios. ImagesFIG. 1 PMID:14310908

  5. Prevalence and genetic characterization of Vibrio vulnificus in raw seafood and seawater in Malaysia.

    PubMed

    Paydar, Mohammadjavad; Thong, Kwai Lin

    2013-10-01

    Vibrio vulnificus is a highly invasive human pathogen that exists naturally in estuarine environment and coastal waters. In this study, we used different PCR assays to detect V. vulnificus in 260 seafood and 80 seawater samples. V. vulnificus was present in about 34 (13%) of the 260 seafood samples and 18 (23%) of the 80 seawater samples. Repetitive extragenic palindromic PCR (REP-PCR) and enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) were applied to subtype the V. vulnificus isolates. Twenty-five REP profiles and 45 ERIC profiles were observed, and the isolates were categorized into 9 and 10 distinct clusters at the similarity of 80%, by REP-PCR and ERIC-PCR, respectively. ERIC-PCR is more discriminative than REP-PCR in subtyping V. vulnificus, demonstrating high genetic diversity among the isolates. PMID:24112583

  6. Non-O1, non-O139 Vibrio cholerae bacteraemia in an Australian population.

    PubMed

    Trubiano, J A; Lee, J Y H; Valcanis, M; Gregory, J; Sutton, B A; Holmes, N E

    2014-05-01

    This retrospective case series identifies the largest cohort of non-O1, non-O139 Vibrio cholerae bacteraemia in an Australian population from 2000 to 2013. We examine the risk factors, epidemiology, clinical presentations and mortality of non-O1, non-O139 V.?cholerae bacteraemia in Victoria and compare them with published cases in the literature. This case series highlights the pathogenic potential of non-O1, non-O139 V.?cholerae and identifies possible associations with host (underlying chronic liver disease and malignancy) and environmental factors (contaminated water supply and raw seafood). Clinicians should be aware of the morbidity and mortality associated with invasive non-O1, non-O139 V.?cholerae infections, particularly in immunocompromised patients. PMID:24816311

  7. Seasonal incidence of Vibrio vulnificus in the Great Bay estuary of New Hampshire and Maine.

    PubMed Central

    O'Neill, K R; Jones, S H; Grimes, D J

    1992-01-01

    Vibrio vulnificus, a normal bacterial inhabitant of estuaries, is of concern because it can be a potent human pathogen, causing septicemia, wound infections, and gastrointestinal disease in susceptible hosts. From May 1989 through December 1990, oysters and/or water were obtained from six areas in the Great Bay estuary of New Hampshire and Maine. Water was also sampled from three freshwater sites that lead into these areas. V. vulnificus was first detected in the estuary in early July and remained present through September. V. vulnificus was isolated routinely during this period from oysters and water of the Squamscott, Piscataqua, and Oyster Rivers but was only isolated twice from the oysters or water of the Great Bay itself. This study determined that there was a strong correlation (by analysis of variance) between temperature, salinity, and the presence of V. vulnificus in water and oysters. However, other unidentified factors appear to influence its presence in certain areas of the estuary. PMID:1444362

  8. Identification and expression of antioxidant and immune defense genes in the surf clam Mesodesma donacium challenged with Vibrio anguillarum.

    PubMed

    Maldonado-Aguayo, W; Lafarga-De la Cruz, F; Gallardo-Escárate, C

    2015-02-01

    The immune system in marine invertebrates is mediated through cellular and humoral components, which act together to address the action of potential pathogenic microorganisms. In bivalve mollusks biomolecules implicated in oxidative stress and recognition of pathogens have been involved in the innate immune response. To better understand the molecular basis of the immune response of surf clam Mesodesma donacium, qPCR approaches were used to identify genes related to its immune response against Vibrio anguillarum infection. Genes related to oxidative stress response and recognition of pathogens like superoxide dismutase (MdSOD), catalase (MdCAT), ferritin (MdFER) and filamin (MdFLMN) were identified from 454-pyrosequencing cDNA library of M. donacium and were evaluated in mantle, adductor muscle and gills. The results for transcripts expression indicated that MdSOD, MdFLMN and MdFER were primarily expressed in the muscle, while MdCAT was more expressed in gills. Challenge experiments with the pathogen V. anguillarum had showed that levels of transcript expression for MdSOD, MdCAT, MdFER, and MdFLMN were positively regulated by pathogen, following a time-dependent expression pattern with significant statistical differences between control and challenge group responses (p<0.05). These results suggest that superoxide dismutase, catalase, ferritin and filamin, could be contributing to the innate immune response of M. donacium against the pathogen V. anguillarum. PMID:25481276

  9. A Chimeric Siderophore Halts Swarming Vibrio**

    PubMed Central

    Böttcher, Thomas; Clardy, Jon

    2014-01-01

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

  10. Vibrio cholerae: lessons for mucosal vaccine design

    PubMed Central

    Bishop, Anne L; Camilli, Andrew

    2011-01-01

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

  11. Molecular characterization of Aeromonas spp. and Vibrio cholerae O1 isolated during a diarrhea outbreak.

    PubMed

    Mendes-Marques, Carina Lucena; Nascimento, Larissa Mélo do; Theophilo, Grace Nazareth Diogo; Hofer, Ernesto; Melo Neto, Osvaldo Pompílio de; Leal, Nilma Cintra

    2012-12-01

    This work aimed to assess pathogenic potential and clonal relatedness of Aeromonas sp. and Vibrio cholerae isolates recovered during a diarrhea outbreak in Brazil. Clinical and environmental isolates were investigated for the presence of known pathogenic genes and clonal relatedness was assessed by intergenic spacer region (ISR) 16S-23S amplification. Four Aeromonas genes (lip, exu, gcat, flaA/B) were found at high overall frequency in both clinical and environmental isolates although the lip gene was specifically absent from selected species. A fifth gene, aerA, was rarely found in A. caviae, the most abundant species. The ISR profile revealed high heterogeneity among the Aeromonas isolates and no correlation with species identification. In contrast, in all the V. cholerae isolates the four genes investigated (ctxA, tcpA, zot and ace) were amplified and revealed homogeneous ISR and RAPD profiles. Although Aeromonas isolates were the major enteric pathogen recovered, their ISR profiles are not compatible with a unique cause for the diarrhea events, while the clonal relationship clearly implicates V. cholerae in those cases from which it was isolated. These results reinforce the need for a better definition of the role of aeromonads in diarrhea and whether they benefit from co-infection with V. cholerae. PMID:23152310

  12. Assessment of the Roles of LuxS, S-Ribosyl Homocysteine, and Autoinducer 2 in Cell Attachment during Biofilm Formation by Listeria monocytogenes EGD-e

    Microsoft Academic Search

    Sylvain Challan Belval; Laurent Gal; Sylvain Margiewes; Dominique Garmyn; Pascal Piveteau; Jean Guzzo

    2006-01-01

    LuxS is responsible for the production of autoinducer 2 (AI-2), which is involved in the quorum-sensing response of Vibrio harveyi. AI-2 is found in several other gram-negative and gram-positive bacteria and is therefore considered a good candidate for an interspecies communication signal molecule. In order to deter- mine if this system is functional in the gastrointestinal pathogen Listeria monocytogenes EGD-e,

  13. Colonization and probiotic effects of lactic acid bacteria in the gut of the abalone Haliotis gigantea

    Microsoft Academic Search

    Shunpei Iehata; Tadashi Inagaki; Suguru Okunishi; Miyo Nakano; Reiji Tanaka; Hiroto Maeda

    2009-01-01

    Strains of lactic acid bacteria (LAB) were isolated from several different sources and evaluated in vitro for potential probiotic\\u000a effects in abalones. Two isolates (Lactobacillus sp. strain a3 and Enterococcus sp. strain s6) were highly resistant to bile salt and\\/or gastric juice and inhibited the growth of three abalone pathogens\\u000a (Listonella anguillarum, Vibrio harveyi, and V. carchariae). Each of the

  14. Population Structure and Evolution of Non-O1/Non-O139 Vibrio cholerae by Multilocus Sequence Typing

    PubMed Central

    Lam, Connie; Leung, Queenie; Ahsan, Sunjukta; Reeves, Peter R.; Nair, G. Balakrish; Lan, Ruiting

    2013-01-01

    Pathogenic non-O1/non-O139 Vibrio cholerae strains can cause sporadic outbreaks of cholera worldwide. In this study, multilocus sequence typing (MLST) of seven housekeeping genes was applied to 55 non-O1/non-O139 isolates from clinical and environmental sources. Data from five published O1 isolates and 17 genomes were also included, giving a total of 77 isolates available for analysis. There were 66 sequence types (STs), with the majority being unique, and only three clonal complexes. The V. cholerae strains can be divided into four subpopulations with evidence of recombination among the subpopulations. Subpopulations I and III contained predominantly clinical strains. PCR screening for virulence factors including Vibrio pathogenicity island (VPI), cholera toxin prophage (CTX?), type III secretion system (T3SS), and enterotoxin genes (rtxA and sto/stn) showed that combinations of these factors were present in the clinical isolates with 85.7% having rtxA, 51.4% T3SS, 31.4% VPI, 31.4% sto/stn (NAG-ST) and 11.4% CTX?. These factors were also present in environmental isolates but at a lower frequency. Five strains previously mis-identified as V. cholerae serogroups O114 to O117 were also analysed and formed a separate population with V. mimicus. The MLST scheme developed in this study provides a framework to identify sporadic cholera isolates by genetic identity. PMID:23776471

  15. Insights into Vibrio cholerae Intestinal Colonization from Monitoring Fluorescently Labeled Bacteria

    PubMed Central

    Millet, Yves A.; Alvarez, David; Ringgaard, Simon; von Andrian, Ulrich H.; Davis, Brigid M.; Waldor, Matthew K.

    2014-01-01

    Vibrio cholerae, the agent of cholera, is a motile non-invasive pathogen that colonizes the small intestine (SI). Most of our knowledge of the processes required for V. cholerae intestinal colonization is derived from enumeration of wt and mutant V. cholerae recovered from orogastrically infected infant mice. There is limited knowledge of the distribution of V. cholerae within the SI, particularly its localization along the villous axis, or of the bacterial and host factors that account for this distribution. Here, using confocal and intravital two-photon microscopy to monitor the localization of fluorescently tagged V. cholerae strains, we uncovered unexpected and previously unrecognized features of V. cholerae intestinal colonization. Direct visualization of the pathogen within the intestine revealed that the majority of V. cholerae microcolonies attached to the intestinal epithelium arise from single cells, and that there are notable regiospecific aspects to V. cholerae localization and factors required for colonization. In the proximal SI, V. cholerae reside exclusively within the developing intestinal crypts, but they are not restricted to the crypts in the more distal SI. Unexpectedly, V. cholerae motility proved to be a regiospecific colonization factor that is critical for colonization of the proximal, but not the distal, SI. Furthermore, neither motility nor chemotaxis were required for proper V. cholerae distribution along the villous axis or in crypts, suggesting that yet undefined processes enable the pathogen to find its niches outside the intestinal lumen. Finally, our observations suggest that host mucins are a key factor limiting V. cholerae intestinal colonization, particularly in the proximal SI where there appears to be a more abundant mucus layer. Collectively, our findings demonstrate the potent capacity of direct pathogen visualization during infection to deepen our understanding of host pathogen interactions. PMID:25275396

  16. Isolation and identification of Vibrio parahaemolyticus from seawater and sediment samples in the southern coast of the Caspian Sea.

    PubMed

    Alipour, Majid; Issazadeh, Khosro; Soleimani, Javad

    2014-01-01

    The objectives of this study were to investigate the occurrence of Vibrio parahaemolyticus in the seawater and its sediment by molecular techniques and conventional microbiological methods. Of 300 samples analyzed, 20.3 % was recorded positive for V. parahaemolyticus. Of the 62 strains isolated, 26 (8.3 %) were obtained from the seawater samples, and 36 (12 %); from sediments. Only three strains (4.83 %) showed hemolytic activity in Wagatsuma agar. The results of this study demonstrated the presence of V. parahaemolyticus in the southern coast of the Caspian Sea (Northern Iran). Furthermore, the PCR approach proved useful for reliable confirmation of species identification. V. parahaemolyticus is an important human pathogen responsible for food-borne gastroenteritis worldwide. These findings indicated the potential sanitary risk associated with the presence of pathogenic V. parahaemolyticus in the Caspian Sea. PMID:24482636

  17. Vibrio alfacsensis sp. nov., isolated from marine organisms.

    PubMed

    Gomez-Gil, Bruno; Roque, Ana; Chimetto, Luciane; Moreira, Ana Paula B; Lang, Elke; Thompson, Fabiano L

    2012-12-01

    Five strains (CAIM 1831(T), CAIM 1832, CAIM 1833, CAIM 1834 and CAIM 1836) were isolated from cultured sole (Solea senegalensis) in two regions of Spain, two strains (CAIM 404 and CAIM 1294) from wild-caught spotted rose snapper (Lutjanus guttatus) in Mexico, and one strain (CAIM 1835) from corals in Brazil. The 16S rRNA gene sequences of the novel isolates showed similarity to Vibrio ponticus (98.2-98.3%, GenBank accession no. AJ630103) and to a lesser degree to Vibrio furnissii (97.2-97.3%, X76336) and to Vibrio fluvialis (96.9-97.1%, X74703). Multilocus sequence analysis clustered these strains closely together and clearly separated them from phylogenetically related species of the genus Vibrio. Genomic fingerprinting by rep-PCR clustered the novel strains according to their geographical origin. Phenotypic analyses showed a large variation among the new strains, but many tests enabled them to be differentiated from other species of the genus Vibrio. The mean ?T(m) values between the strains analysed here and closely related type strains were above 6.79 °C. The values between the novel isolates were below 2.35 °C, well outside the limit suggested for the delineation of a bacterial species. The phenotypic and genotypic data presented here clearly place these new strains as a coherent group within the genus Vibrio, for which we propose the name Vibrio alfacsensis sp. nov. with CAIM 1831(T) (?= DSM 24595(T) = S277(T)) as the type strain. PMID:22286904

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

    PubMed

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

    2014-01-01

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

  19. Detection of Escherichia coli, Salmonella species, and Vibrio cholerae in tap water and bottled drinking water in Isfahan, Iran

    PubMed Central

    2013-01-01

    Background The quality of drinking water has an important role in human infection and disease. This study was aimed at comparing polymerase chain reaction and culture in detecting Escherichia coli, Salmonella species and Vibrio cholera in tape water and bottled drinking water in various seasons in Isfahan province, Iran. Methods A total of 448 water samples from tap water and bottled mineral water were taken over 6 months, from July 2010 to December 2010, and after filtration, samples were examined by culture and polymerase chain reaction methods for detection of Escherichia coli, Salmonella species, and Vibrio cholerae. Results The culture method showed that 34 (7.58%), 4 (0.89%) and 3 (0.66%) of all 448 water samples were positive for Escherichia coli, Salmonella species, and Vibrio cholera, respectively. The uidA gene from Escherichia coli, IpaB gene from Salmonella species, and epsM gene from Vibrio cholera were detected in 38 (26.38%), 5 (3.47%), and 3 (2.08%) of 144 tap-water samples, respectively. Escherichia coli was detected in 8 (2.63%) of 304 samples of bottled drinking water from 5 companies. The water of southern part of Isfahan and company 5 had the highest prevalence of bacteria. The Escherichia coli water contamination was significantly higher (P?Vibrio cholerae as water-borne pathogens in tap water and bottled drinking water of Isfahan, Iran. The present study showed the important public health problem in Isfahan, Iran. PMID:23742181

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

    PubMed Central

    Spira, W M; Fedorka-Cray, P J

    1983-01-01

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

  1. Distribution and dynamics of epidemic and pandemic Vibrio parahaemolyticus virulence factors.

    PubMed

    Ceccarelli, Daniela; Hasan, Nur A; Huq, Anwar; Colwell, Rita R

    2013-01-01

    Vibrio parahaemolyticus, autochthonous to estuarine, marine, and coastal environments throughout the world, is the causative agent of food-borne gastroenteritis. More than 80 serotypes have been described worldwide, based on antigenic properties of the somatic (O) and capsular (K) antigens. Serovar O3:K6 emerged in India in 1996 and subsequently was isolated worldwide, leading to the conclusion that the first V. parahaemolyticus pandemic had taken place. Most strains of V. parahaemolyticus isolated from the environment or seafood, in contrast to clinical strains, do not produce a thermostable direct hemolysin (TDH) and/or a TDH-related hemolysin (TRH). Type 3 secretion systems (T3SSs), needle-like apparatuses able to deliver bacterial effectors into host cytoplasm, were identified as triggering cytotoxicity and enterotoxicity. Type 6 secretion systems (T6SS) predicted to be involved in intracellular trafficking and vesicular transport appear to play a role in V. parahaemolyticus virulence. Recent advances in V. parahaemolyticus genomics identified several pathogenicity islands (VpaIs) located on either chromosome in both epidemic and pandemic strains and comprising additional colonization factors, such as restriction-modification complexes, chemotaxis proteins, classical bacterial surface virulence factors, and putative colicins. Furthermore, studies indicate strains lacking toxins and genomic regions associated with pathogenicity may also be pathogenic, suggesting other important virulence factors remain to be identified. The unique repertoire of virulence factors identified to date, their occurrence and distribution in both epidemic and pandemic strains worldwide are described, with the aim of highlighting the complexity of V. parahaemolyticus pathogenicity as well as its dynamic genome. PMID:24377090

  2. Vibrio coralliilyticus strain OCN008 is an etiological agent of acute Montipora white syndrome.

    PubMed

    Ushijima, Blake; Videau, Patrick; Burger, Andrew H; Shore-Maggio, Amanda; Runyon, Christina M; Sudek, Mareike; Aeby, Greta S; Callahan, Sean M

    2014-04-01

    Identification of a pathogen is a critical first step in the epidemiology and subsequent management of a disease. A limited number of pathogens have been identified for diseases contributing to the global decline of coral populations. Here we describe Vibrio coralliilyticus strain OCN008, which induces acute Montipora white syndrome (aMWS), a tissue loss disease responsible for substantial mortality of the coral Montipora capitata in K?ne'ohe Bay, Hawai'i. OCN008 was grown in pure culture, recreated signs of disease in experimentally infected corals, and could be recovered after infection. In addition, strains similar to OCN008 were isolated from diseased coral from the field but not from healthy M. capitata. OCN008 repeatedly induced the loss of healthy M. capitata tissue from fragments under laboratory conditions with a minimum infectious dose of between 10(7) and 10(8) CFU/ml of water. In contrast, Porites compressa was not infected by OCN008, indicating the host specificity of the pathogen. A decrease in water temperature from 27 to 23°C affected the time to disease onset, but the risk of infection was not significantly reduced. Temperature-dependent bleaching, which has been observed with the V. coralliilyticus type strain BAA-450, was not observed during infection with OCN008. A comparison of the OCN008 genome to the genomes of pathogenic V. coralliilyticus strains BAA-450 and P1 revealed similar virulence-associated genes and quorum-sensing systems. Despite this genetic similarity, infections of M. capitata by OCN008 do not follow the paradigm for V. coralliilyticus infections established by the type strain. PMID:24463971

  3. Detection and quantification of Vibrio parahaemolyticus in shellfish from Italian production areas.

    PubMed

    Suffredini, Elisabetta; Mioni, Renzo; Mazzette, Rina; Bordin, Paola; Serratore, Patrizia; Fois, Federica; Piano, Annamaria; Cozzi, Loredana; Croci, Luciana

    2014-08-01

    Vibrio parahaemolyticus is a marine microorganism, recognized as an important cause of foodborne illness particularly in Asia, South America and United States. Outbreaks are rarely reported in Europe, but they can occur unexpectedly in relation, among other reasons, to the spread of highly virulent strains. It is known that the risk is proportional to exposure levels to pathogenic V. parahaemolyticus (i.e. carrying the tdh and/or the trh genes) but currently there is a lack of occurrence data for pathogenic V. parahaemolyticus in shellfish production areas of the Member States. In this study a total of 147 samples of bivalve molluscs, from harvesting areas of two Italian regions (Sardinia and Veneto) were analyzed for Escherichia coli and salmonella, according to Reg 2073/2005, and for detection and enumeration of total and toxigenic V. parahaemolyticus strains using a new DNA colony hybridization method. Environmental parameters (water temperature and salinity) were also recorded. Results of E. coli were consistently in agreement with the legislation limits for the harvesting class of origin and Salmonella was detected only in one sample. The average contamination levels for total V. parahaemolyticus were 84 and 73 CFU/g respectively for Sardinia and Veneto, with the highest value reaching 8.7 × 10(3)CFU/g. Nineteen samples (12.9%) resulted positive for the presence of potentially pathogenic V. parahaemolyticus strains, with levels ranging between 10 and 120 CFU/g and most of the positive samples (n=17) showing values equal or below 20 CFU/g. A significant correlation (r=0.41) was found between water temperature and V. parahaemolyticus levels, as well as with isolation frequency. The data provided in this study on contamination levels of total and potentially pathogenic V. parahaemolyticus, seasonal distribution and correlation with water temperature, will help in defining appropriate monitoring programs and post-harvest policies for this hazard, improving the management of the harvesting areas and the safety of bivalve molluscs. PMID:24810197

  4. Bioactive potential of Streptomyces against fish and shellfish pathogens

    PubMed Central

    Selvakumar, D; Arun, K; Suguna, S; Kumar, D; Dhevendaran, K

    2010-01-01

    Background and Objectives In the present study, isolation of Streptomyces associated with marine sponges and its bioactive potential against fish and shellfish pathogens were assessed. The Streptomyces sp. were isolated from the marine sponges namely Callyspongia diffusa, Mycale mytilorum, Tedania anhelans and Dysidea fragilis collected from Vizhinjam port, situated in the South-West coast of India. Materials and Methods The Streptomyces associated with marine sponges were isolated using specific ISP media. The isolates of Streptomyces were characterized for their colony characteristics, morphological properties, physiological and biochemical properties and were tentatively identified. The strains were cultivated on a lab scale level as shake-flask cultures and the crude extracts of the bioactive compounds obtained with ethyl acetate were screened biologically and chemically. By biological screening, the extracts were analyzed for their activity against fish and shellfish pathogens namely Aeromonas hydrophila, Serratia sp. and Vibrio spp, using the disk and agar-well diffusion bioassay method, while by chemical screening the crude culture extracts were analyzed by TLC and UV–Vis spectrophotometer. Results Ninety-four isolates were found to be associated with marine sponges, among them only seven strains showed antagonism against fish and shellfish pathogens. Analysis of morphological, physiological and biochemical characteristics suggested that these strains belonged to the genus Streptomyces. The initial screening of the isolates by spot inoculation method exhibited antibacterial activity against Aeromonas hydrophila. In-vitro screening of the submerge culture extracts showed positive inhibition against the fish and shellfish pathogens namely Aeromonas hydrophila, Serratia sp. and Vibrio spp. The screening of bioactive compounds confirmed the production of polyene substances by UV spectrum, which resulted in absorbance peaks ranging from 225 to 245 nm and TLC analysis yielded Rf values ranging from 0.40 to 0.78. Conclusion The results suggest that the seven Streptomyces strains isolated from marine sponges produce potential antibacterial compounds against fish and shellfish pathogens. PMID:22347566

  5. Rapid identification of Vibrio cholerae by darkfield microscopy*

    PubMed Central

    Benenson, A. S.; Islam, M. R.; Greenough, W. B.

    1964-01-01

    This article describes a rapid, simple and reproducible method for detecting Vibrio cholerae in diarrhoeal patients. The method involves darkfield examination of a liquid stool specimen or a rectal swab immersed in broth and immobilization of V. cholerae by the addition of specific vibrio antisera. The authors state that in 80% of cases a definitive diagnosis is available within five minutes. There is no need for elaborate equipment or long training of technicians and the method is easily performed by one person in the field. PMID:14215188

  6. RAPID IDENTIFICATION OF VIBRIO CHOLERAE BY DARKFIELD MICROSCOPY.

    PubMed

    BENENSON, A S; ISLAM, M R; GREENOUGH, W B

    1964-01-01

    This article describes a rapid, simple and reproducible method for detecting Vibrio cholerae in diarrhoeal patients. The method involves darkfield examination of a liquid stool specimen or a rectal swab immersed in broth and immobilization of V. cholerae by the addition of specific vibrio antisera. The authors state that in 80% of cases a definitive diagnosis is available within five minutes. There is no need for elaborate equipment or long training of technicians and the method is easily performed by one person in the field. PMID:14215188

  7. Vibrio vulnificus Secretes an Insulin-degrading Enzyme That Promotes Bacterial Proliferation in Vivo.

    PubMed

    Kim, In Hwang; Kim, Ik-Jung; Wen, Yancheng; Park, Na-Young; Park, Jinyoung; Lee, Keun-Woo; Koh, Ara; Lee, Ji-Hyun; Koo, Seung-Hoi; Kim, Kun-Soo

    2015-07-24

    We describe a novel insulin-degrading enzyme, SidC, that contributes to the proliferation of the human bacterial pathogen Vibrio vulnificus in a mouse model. SidC is phylogenetically distinct from other known insulin-degrading enzymes and is expressed and secreted specifically during host infection. Purified SidC causes a significant decrease in serum insulin levels and an increase in blood glucose levels in mice. A comparison of mice infected with wild type V. vulnificus or an isogenic sidC-deletion strain showed that wild type bacteria proliferated to higher levels. Additionally, hyperglycemia leads to increased proliferation of V. vulnificus in diabetic mice. Consistent with these observations, the sid operon was up-regulated in response to low glucose levels through binding of the cAMP-receptor protein (CRP) complex to a region upstream of the operon. We conclude that glucose levels are important for the survival of V. vulnificus in the host, and that this pathogen uses SidC to actively manipulate host endocrine signals, making the host environment more favorable for bacterial survival and growth. PMID:26041774

  8. Integrative genome-scale metabolic analysis of Vibrio vulnificus for drug targeting and discovery

    PubMed Central

    Kim, Hyun Uk; Kim, Soo Young; Jeong, Haeyoung; Kim, Tae Yong; Kim, Jae Jong; Choy, Hyon E; Yi, Kyu Yang; Rhee, Joon Haeng; Lee, Sang Yup

    2011-01-01

    Although the genomes of many microbial pathogens have been studied to help identify effective drug targets and novel drugs, such efforts have not yet reached full fruition. In this study, we report a systems biological approach that efficiently utilizes genomic information for drug targeting and discovery, and apply this approach to the opportunistic pathogen Vibrio vulnificus CMCP6. First, we partially re-sequenced and fully re-annotated the V. vulnificus CMCP6 genome, and accordingly reconstructed its genome-scale metabolic network, VvuMBEL943. The validated network model was employed to systematically predict drug targets using the concept of metabolite essentiality, along with additional filtering criteria. Target genes encoding enzymes that interact with the five essential metabolites finally selected were experimentally validated. These five essential metabolites are critical to the survival of the cell, and hence were used to guide the cost-effective selection of chemical analogs, which were then screened for antimicrobial activity in a whole-cell assay. This approach is expected to help fill the existing gap between genomics and drug discovery. PMID:21245845

  9. Quantitative modeling for risk assessment of Vibrio parahaemolyticus in bloody clams in southern Thailand.

    PubMed

    Yamamoto, Akio; Iwahori, Jun'ichiro; Vuddhakul, Varaporn; Charernjiratragul, Wilawan; Vose, David; Osaka, Ken; Shigematsu, Mika; Toyofuku, Hajime; Yamamoto, Shigeki; Nishibuchi, Mitsuaki; Kasuga, Fumiko

    2008-05-10

    A risk assessment of Vibrio parahaemolyticus in bloody clams (Anadara granosa) consumed in southern Thailand was conducted. This study estimated the prevalence and concentration of pathogenic V. parahaemolyticus in bloody clams at harvest and retail stages; and during this process, methods to detect the total and pathogenic V. parahaemolyticus were investigated. Consumption of bloody clams and cooking efficiency were studied using interviews and on-site observation of consumers. A beta-Poisson dose-response model was used to estimate probability of illness applying estimation methods for the most likely parameter values presented by USFDA. Microbial and behavioral data were analyzed by developing a stochastic model and the simulation gave a mean number of times a person would get ill with V. parahaemolyticus by consuming bloody clams at 5.6 x 10(-4)/person/year. Sensitivity analysis demonstrated the fraction of people who did not boil the clams properly was the primary factor in increasing risk. This study serves as an example of how a microbiological risk assessment with limited data collection and international cooperation leads to valuable local insight. PMID:18405992

  10. Host-Like Carbohydrates Promote Bloodstream Survival of Vibrio vulnificus In Vivo.

    PubMed

    Lubin, Jean-Bernard; Lewis, Warren G; Gilbert, Nicole M; Weimer, Cory M; Almagro-Moreno, Salvador; Boyd, E Fidelma; Lewis, Amanda L

    2015-08-01

    Sialic acids are found on all vertebrate cell surfaces and are part of a larger class of molecules known as nonulosonic acids. Many bacterial pathogens synthesize related nine-carbon backbone sugars; however, the role(s) of these non-sialic acid molecules in host-pathogen interactions is poorly understood. Vibrio vulnificus is the leading cause of seafood-related death in the United States due to its ability to quickly access the host bloodstream, which it can accomplish through gastrointestinal or wound infection. However, little is known about how this organism persists systemically. Here we demonstrate that sialic acid-like molecules are present on the lipopolysaccharide of V. vulnificus, are required for full motility and biofilm formation, and also contribute to the organism's natural resistance to polymyxin B. Further experiments in a murine model of intravenous V. vulnificus infection demonstrated that expression of nonulosonic acids had a striking benefit for bacterial survival during bloodstream infection and dissemination to other tissues in vivo. In fact, levels of bacterial persistence in the blood corresponded to the overall levels of these molecules expressed by V. vulnificus isolates. Taken together, these results suggest that molecules similar to sialic acids evolved to facilitate the aquatic lifestyle of V. vulnificus but that their emergence also resulted in a gain of function with life-threatening potential in the human host. PMID:26015477

  11. The Apparent Quorum-Sensing Inhibitory Activity of Pyrogallol Is a Side Effect of Peroxide Production

    PubMed Central

    Pande, Gde Sasmita Julyantoro; Baruah, Kartik; Bossier, Peter

    2013-01-01

    There currently is more and more interest in the use of natural products, such as tea polyphenols, as therapeutic agents. The polyphenol compound pyrogallol has been reported before to inhibit quorum-sensing-regulated bioluminescence in Vibrio harveyi. Here, we report that the addition of 10 mg · liter?1 pyrogallol protects both brine shrimp (Artemia franciscana) and giant river prawn (Macrobrachium rosenbergii) larvae from pathogenic Vibrio harveyi, whereas the compound showed relatively low toxicity (therapeutic index of 10). We further demonstrate that the apparent quorum-sensing-disrupting activity is a side effect of the peroxide-producing activity of this compound rather than true quorum-sensing inhibition. Our results emphasize that verification of minor toxic effects by using sensitive methods and the use of appropriate controls are essential when characterizing compounds as being able to disrupt quorum sensing. PMID:23545532

  12. Pathological analysis of hemolymphs of Charybdis japonica infected with Vibrio alginolyticus.

    PubMed

    Xu, Shan-Liang; Qiu, Cheng-Gong; Zhou, Wei; Wang, Dan-Li; Jia, Chao-Yan; Wang, Chun-Lin

    2013-11-01

    We explored the pathogenic mechanism of Vibrio alginolyticus in the stone crab Charybdis japonica by studying the hemolymph of C. japonica artificially infected by V. alginolyticus. To this end, Wright-Geimsa staining and electron microscopy were used, and phenoloxidase (PO) activity and the immune protection rate of C. japonica injected with immune polysaccharide during infection were analyzed. The results indicated that the total hemocyte and hyaline hemocyte (HH) counts in diseased crabs were significantly lower than those in healthy crabs (P < 0.05), whereas the large granule hemocytes (LGHs) were significantly higher in diseased crabs than in healthy crabs (P < 0.05). The cellular sizes of HHs and LGHs showed an increasing trend after V. alginolyticus infection, while the nuclear/cytoplasmic ratio (NP) of these cells showed a sharp decline after V. alginolyticus infection (P < 0.05). Micro-pathological analysis of hemocytes revealed fewer hemocytes in the hemolymph of diseased crabs and the presence of disintegrated cells. Ultrastructural and micro-pathological analyses showed damage in all types of hemocytes. The mitochondria were damaged and incomplete in structure, parts of the nuclear membrane were anamorphic and parts of the nuclei had shrunk, hematocyte nuclei exhibited heterochromatinization, hemocyte granules were increased in the polysaccharide-treated group infected with V. alginolyticus, and the numbers of mitochondria and rough endoplasmic reticulum were also increased. PO activity in the two Vibrio-infected groups peaked at 6 h and 24 h after infection, respectively, and PO activity increased in the hemolymph of infected crabs but sharply decreased with prolonged infection. Finally, the PO activities in the two Vibrio-infected groups were significantly lower than controls at 120 h post-infection (P < 0.05). Interestingly, PO activity was higher in polysaccharide-treated crabs than non-polysaccharide-challenged infected crabs, resulting in an immunoprotective rate of 69.64% at 7 days post-infection. This phenomenon suggests that polysaccharides could enhance the organism's antibacterial defenses by improving immune-related enzyme activity. PMID:24036334

  13. Detection of major diarrheagenic bacterial pathogens by multiplex PCR panels.

    PubMed

    Sjöling, Åsa; Sadeghipoorjahromi, Leila; Novak, Daniel; Tobias, Joshua

    2015-03-01

    Diarrheal diseases remain a major threat to the youngest population in low- and middle-income countries. The main bacterial pathogens causing diarrhea are diarrheagenic Escherichia coli (DEC) that consists of enteroaggregative (EAEC), enteropathogenic (EPEC), enterotoxigenic (ETEC), enterohemorrhagic EHEC and enteroinvasive E. coli (EIEC), Salmonella, Shigella spp. (S. dysenteria, S. sonnei, S. flexneri) Campylobacter (C. coli, C. jejuni), Vibrio (V. vulnificus, V. parahaemolyticusm, V. cholerae), Yersinia enterocolitica and Aeromonas hydrophila. The aim of this study was to set up rapid multiplex PCR (mPCR) panels to identify these diarrheagenic pathogens based on their specific virulence genes. Primers against specific target genes were combined into three mPCR panels: one for diarrheal E. coli, one for pathogens causing mainly bloody diarrhea, and the third for the remaining pathogens. The panels were tested against a set of stool samples from Swedish children with diarrhea and controls and the analysis identified bacterial pathogens in 14/54 (26%) of the samples. These results show that our three developed mPCR panels can detect main bacterial diarrheagenic pathogens in clinical samples. PMID:25542594

  14. Members of the human gut microbiota involved in recovery from Vibrio cholerae infection

    PubMed Central

    Hsiao, Ansel; Shamsir Ahmed, A.M.; Subramanian, Sathish; Griffin, Nicholas W.; Drewry, Lisa L.; Petri, William A.; Haque, Rashidul; Ahmed, Tahmeed; Gordon, Jeffrey I.

    2015-01-01

    Given the global burden of diarrheal diseases1, it is important to understand how members of the gut microbiota affect the risk for, course of, and recovery from disease in children and adults. The acute, voluminous diarrhea caused by Vibrio cholerae represents a dramatic example of enteropathogen invasion and gut microbial community disruption. We have conducted a detailed time-series metagenomic study of fecal microbiota collected during the acute diarrheal and recovery phases of cholera in a cohort of Bangladeshi adults living in an area with a high burden of disease2. We find that recovery is characterized by a pattern of accumulation of bacterial taxa that shows similarities to the pattern of assembly/maturation of the gut microbiota in healthy Bangladeshi children3. To define underlying mechanisms, we introduced into gnotobiotic mice an artificial community that was composed of human gut bacterial species that directly correlate with recovery from cholera in adults and are indicative of normal microbiota maturation in healthy Bangladeshi children3. One of the species, Ruminococcus obeum, exhibited consistent increases in its relative abundance upon V. cholerae infection of the mice. Follow-up analyses, including mono- and co-colonization studies, established that R. obeum restricts V. cholerae colonization, that R. obeum luxS [autoinducer-2 (AI-2) synthase] expression and AI-2 production increase significantly with V. cholerae invasion, and that R. obeum AI-2 causes quorum-sensing mediated repression of several V. cholerae colonization factors. Co-colonization with V. cholerae mutants disclosed that R. obeum AI-2 reduces Vibrio colonization/pathogenicity through a novel pathway that does not depend on the V. cholerae AI-2 sensor, LuxP. The approach described can be used to mine the gut microbiota of Bangladeshi or other populations for members that use autoinducers and/or other mechanisms to limit colonization with V. cholerae, or conceivably other enteropathogens. PMID:25231861

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

    PubMed

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

    2015-04-01

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

  16. Iron-binding compounds and related outer membrane proteins in Vibrio cholerae non-O1 strains from aquatic environments.

    PubMed

    Amaro, C; Aznar, R; Alcaide, E; Lemos, M L

    1990-08-01

    A total of 156 strains of Vibrio cholerae non-O1 from aquatic origins were examined for the presence of iron uptake mechanisms and compared with O1 strains and other Vibrio species. All non-O1 strains were able to grow in iron-limiting conditions, with MICs of ethylenediaminedi (O-hydroxyphenylacetic acid) ranging from 20 microM to 2 mM. The production of siderophores was demonstrated by growth in chrome azurol S agar and cross-feeding assays. All strains produced phenolate-type compounds, as assessed by the chemical tests and by bioassays with Salmonella typhimurium enb-7. Some of the strains also promoted the growth of S. typhimurium enb-1 (which can use only enterobactin as a siderophore) as well as some strains of Vibrio anguillarum deficient in the anguibactin-mediated system. The chromatographic analyses and absorption spectra of siderophores extracted from culture supernatants suggest that vibriobactin may be produced by the strains examined. Interestingly, some strains also produced hydroxamate-type compounds, as determined by chemical tests, and were able to promote the growth of an aerobactin-deficient strain of Escherichia coli. These results were confirmed by the absorption spectra and chromatographic analyses of the culture extracts. The synthesis of iron-regulated outer membrane proteins in representative strains was also examined. The molecular sizes of the main induced proteins ranged from 70 to 78 kilodaltons. These results indicate that several iron uptake mechanisms which could be involved in environmental survival and pathogenicity are present in environmental V. cholerae non-O1 strains. PMID:2144956

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

    PubMed Central

    de Souza Santos, Marcela

    2014-01-01

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

  18. Behavior of Vibrio cholerae in hot foods.

    PubMed Central

    Makukutu, C A; Guthrie, R K

    1986-01-01

    Four food types held hot at 45 to 60 degrees C were deliberately contaminated with O1 and non-O1 Vibrio cholerae strains. These organisms were assayed for survival and recovery from the foods within 1 h of the time the food was kept hot. The results showed no growth of V. cholerae non-O1 on thiosulfate-citrate bile-sucrose agar plates after 24 h of incubation at 37 degrees C for food held hot at 50 to 60 degrees C. Growth was low for V. cholerae O1 and was not achieved in some instances in which foods were held at either 55 or 60 degrees C after 40 or 60 min of from the time the food was kept hot. Both organisms, however, were recovered equally from all food types held at all temperatures after 48 h of incubation. When incubated for an additional 24 h, the organisms grew to unusually small-sized colonies, measuring 0.1 to 0.3 mm in diameter, on the same agar plates that were negative for growth after an initial 24 h of incubation. It was concluded that V. cholerae survived the period of time held at hot temperatures. Although the organisms were not recovered from some foods when held at some of the temperatures and times after 24 h of incubation, they remained viable. An incubation period of 48 h at 37 degrees C was found to be appropriate for the recovery of V. cholerae from hot foods. PMID:3777928

  19. Characterization of tryptophanase from Vibrio cholerae.

    PubMed

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

    2015-01-01

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

  20. Comparison of protein expression profiles of the hepatopancreas in Fenneropenaeus chinensis challenged with heat-inactivated Vibrio anguillarum and white spot syndrome virus.

    PubMed

    Jiang, Hao; Li, Fuhua; Zhang, Jiquan; Zhang, Jinkang; Huang, Bingxin; Yu, Yang; Xiang, Jianhai

    2014-02-01

    Fenneropenaeus chinensis (Chinese shrimp) culture industry, like other Penaeidae culture, has been seriously affected by the shrimp diseases caused by bacteria and virus. To better understand the mechanism of immune response of shrimp to different pathogens, proteome research approach was utilized in this study. Firstly, the soluble hepatopancreas protein samples in adult Chinese shrimp among control, heat-inactivated Vibrio-challenged and white spot syndrome virus-infected groups were separated by 2-DE (pH range, 4-7; sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and pH range, 3-10; tricine-SDS-PAGE). Then the differentially expressed protein spots (?1.5-fold or ?0.67-fold averagely of controls) were analyzed by LC-ESI-MS/MS. Using Mascot online database searching algorithm and SEQUEST searching program, 48 and 49 differentially expressed protein spots were successfully identified in response to Vibrio and white spot syndrome virus infection, respectively. Based on these results, we discussed the mechanism of immune response of the shrimp and shed light on the differences between immune response of shrimp toward Vibrio and white spot syndrome virus. This study also set a basis for further analyses of some key genes in immune response of Chinese shrimp. PMID:24057166

  1. Transcriptome Analysis and Discovery of Genes Involved in Immune Pathways from Coelomocytes of Sea Cucumber (Apostichopus japonicus) after Vibrio splendidus Challenge.

    PubMed

    Gao, Qiong; Liao, Meijie; Wang, Yingeng; Li, Bin; Zhang, Zheng; Rong, Xiaojun; Chen, Guiping; Wang, Lan

    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 splendidus challenge were collected for analysis. A total of 319,455,942 trimmed reads were obtained, which were assembled into 186,658 contigs. After that, 89,891 representative contigs (without isoform) were clustered. The analysis of the gene expression profiling identified 358 differentially expression genes (DEGs) in the bacterial-resistant group, and 102 DEGs in the bacterial-susceptible group, compared with that in control group. According to the reported references and annotation information from BLAST, GO and KEGG, 30 putative bacterial-resistant genes and 19 putative bacterial-susceptible genes were identified from DEGs. The qRT-PCR results were consistent with the RNA-Seq results. Furthermore, many DGEs were involved in immune signaling related pathways, such as Endocytosis, Lysosome, MAPK, Chemokine and the ERBB signaling pathway. PMID:26193268

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

    PubMed Central

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

    2011-01-01

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

  3. Visick Lab: Home of the Vibrio-Euprymna Symbiosis

    NSDL National Science Digital Library

    Karen Visick

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

  4. Detection of Vibrio parahaemolyticus in cockle ( Anadara granosa) by PCR

    Microsoft Academic Search

    Lesley Maurice Bilung; Son Radu; Abdul Rani Bahaman; Raha Abdul Rahim; Suhaimi Napis; Michael Wong Clemente Vui Ling; Gwendelynne Bulan Tanil; Mitsuaki Nishibuchi

    2005-01-01

    This study aimed to determine the occurrence of Vibrio parahaemolyticus in cockles (Anadara granosa) at a harvesting area and to detect the presence of virulent strains carrying the thermostable direct hemolysin (tdh) and TDH-related hemolysin genes (trh) using PCR. Of 100 samples, 62 were positive for the presence of V. parahaemolyticus with an MPN (most probable number) value greater than

  5. Recombinant nontoxinogenic Vibrio cholerae strains as attenuated cholera vaccine candidates

    Microsoft Academic Search

    James B. Kaper; Hank Lockman; Mary M. Baldini; Myron M. Levine

    1984-01-01

    An ideal vacine does not yet exist to prevent cholera, a significant health problem in many less developed countries. Vibrio cholerae, the agent of epidemic and endemic cholera, colonizes the small bowel and secretes a potent enterotoxin that consists of a single A subunit, which stimulates adenylate cyclase activity, and five identical B summits which bind to the ganglioside GM1

  6. Transcriptome analysis revealed changes of multiple genes involved in immunity in Cynoglossus semilaevis during Vibrio anguillarum infection.

    PubMed

    Zhang, Xiang; Wang, Shaolin; Chen, Songlin; Chen, Yadong; Liu, Yang; Shao, Changwei; Wang, Qilong; Lu, Yang; Gong, Guangye; Ding, Shaoxiong; Sha, Zhenxia

    2015-03-01

    Half-smooth tongue sole (Cynoglossus semilaevis) is one of the most valuable marine aquatic species in Northern China. Given to the rapid development of aquaculture industry, the C. semilaevis was subjected to disease-causing bacteria Vibrio anguillarum. It therefore is indispensable and urgent to understand the mechanism of C. semilaevis host defense against V. anguillarum infection. In the present study, the extensively analysis at the transcriptome level for V. Anguillarum disease in tongue sole was carried out. In total, 94,716 high quality contigs were generated from 75,884,572 clean reads in three libraries (HOSG, NOSG, and CG). 22,746 unigenes were identified when compared with SwissProt, an NR protein database and NT nucleotide database. 954 genes exhibiting the differentially expression at least one pair of comparison in all three libraries were identified. GO enrichment for these genes revealed gene response to biotic stimulus, immune system regulation, and immune response and cytokine production. Further, the pathways such as complement and coagulation cascades and Vibrio cholerae infection pathways were enriched in defensing of pathogen. Besides, 13,428 SSRs and 118,239 SNPs were detected in tongue sole, providing further support for genetic variation and marker-assisted selection in future. In summary, this study identifies several putative immune pathways and candidate genes deserving further investigation in the context of development of therapeutic regimens and lays the foundation for selecting resistant lines of C. semilaevis against V. anguillarum. PMID:25543033

  7. Novel quantitative TaqMan® MGB real-time PCR for sensitive detection of Vibrio aestuarianus in Crassostrea gigas.

    PubMed

    McCleary, S; Henshilwood, K

    2015-06-01

    Validation of a novel quantitative real-time PCR using TaqMan® minor groove binder (MGB) chemistry is described for sensitive and rapid detection of Vibrio aestuarianus, an increasingly important pathogen of Pacific cupped oyster Crassostrea gigas aquaculture. Primers and TaqMan® MGB hydrolysis probe were designed to specifically amplify a 58bp DNA fragment of the V. aestuarianus dnaJ gene. Real-time PCR selectivity was empirically tested using DNA extracted from isolates of V. aestuarianus and a selection of different aquatic bacterial species, including other Vibrio spp. Theoretical selectivity was assessed through sequence comparison using the NCBI BLAST similarity tool. Quantitative PCR plasmid standards were generated to test assay linearity, amplification efficiency and the limit of quantitation (LOQ), according to International Organisation for Standardisation ISO 16140 validation recommendations. LOQ ranged between 5 and 10 PCR copies, although the detection range extended beyond this with reduced precision. Applied performance was tested using C. gigas samples taken from a selection of Irish aquaculture sites. Increasing levels of V. aestuarianus, accompanied by the development of tissue pathology in examined oysters, were found at 1 site that was sampled repeatedly in 2013. Rapid, sensitive and reproducible detections of V. aestuarianus from C. gigas tissue samples were attained during this validation study with a small sample size, and a practical application for disease management is described. PMID:26036831

  8. The Type II Secretion System Delivers Matrix Proteins for Biofilm Formation by Vibrio cholerae

    PubMed Central

    Johnson, Tanya L.; Fong, Jiunn C.; Rule, Chelsea; Rogers, Andrew; Yildiz, Fitnat H.

    2014-01-01

    Gram-negative bacteria have evolved several highly dedicated pathways for extracellular protein secretion, including the type II secretion (T2S) system. Since substrates secreted via the T2S system include both virulence factors and degradative enzymes, this secretion system is considered a major survival mechanism for pathogenic and environmental species. Previous analyses revealed that the T2S system mediates the export of ?20 proteins in Vibrio cholerae, a human pathogen that is indigenous to the marine environment. Here we demonstrate a new role in biofilm formation for the V. cholerae T2S system, since wild-type V. cholerae was found to secrete the biofilm matrix proteins RbmC, RbmA, and Bap1 into the culture supernatant, while an isogenic T2S mutant could not. In agreement with this finding, the level of biofilm formation in a static microtiter assay was diminished in T2S mutants. Moreover, inactivation of the T2S system in a rugose V. cholerae strain prevented the development of colony corrugation and pellicle formation at the air-liquid interface. In contrast, extracellular secretion of the exopolysaccharide VPS, an essential component of the biofilm matrix, remained unaffected in the T2S mutants. Our results indicate that the T2S system provides a mechanism for the delivery of extracellular matrix proteins known to be important for biofilm formation by V. cholerae. Because the T2S system contributes to the pathogenicity of V. cholerae by secreting proteins such as cholera toxin and biofilm matrix proteins, elucidation of the molecular mechanism of T2S has the potential to lead to the development of novel preventions and therapies. PMID:25266381

  9. Household Transmission of Vibrio cholerae in Bangladesh

    PubMed Central

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

    2014-01-01

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

  10. Antibacterial Activity of Biosecur® Citrus Extract Surface Cleaner Against Vibrio Vulnificus

    PubMed Central

    Cormier, Jiemin; Scott, Ronson; Janes, Marlene

    2013-01-01

    This study evaluated the antibacterial activity of Biosecur® citrus extract surface cleaner against Vibrio vulnificus using plate count method. Two concentrations, 0.5% and 2% of Biosecur® surface cleaner were plated on Vibrio vulnificus Agar (VVA) and tested for reduction of Vibrio vulnificus. In order to investigate the lasting residual activity of Biosecur®, antibacterial activity tests were also performed at time intervals up to 2.5 h after Biosecur® was plated on VVA. Biosecur® showed 6-log reduction of Vibrio vulnificus at 2%, and 3-log reduction of Vibrio vulnificus at 0.5%. The antibacterial activity of 2% Biosecur® against Vibrio vulnificus was shown to be equivalent to that of tetracycline. The residual activity of 2% Biosecur® was shown to maintain for at least 2.5 h after application. This study confirmed the high activity and long lasting residual effect of a safe, non-toxic organic food grade surface cleaner. PMID:24302976

  11. Bright luminescence of Vibrio fischeri aconitase mutants reveals a connection between citrate and the Gac/Csr regulatory system.

    PubMed

    Septer, Alecia N; Bose, Jeffrey L; Lipzen, Anna; Martin, Joel; Whistler, Cheryl; Stabb, Eric V

    2015-01-01

    The Gac/Csr regulatory system is conserved throughout the ?-proteobacteria and controls key pathways in central carbon metabolism, quorum sensing, biofilm formation and virulence in important plant and animal pathogens. Here we show that elevated intracellular citrate levels in a Vibrio fischeri aconitase mutant correlate with activation of the Gac/Csr cascade and induction of bright luminescence. Spontaneous or directed mutations in the gene that encodes citrate synthase reversed the bright luminescence of aconitase mutants, eliminated their citrate accumulation and reversed their elevated expression of CsrB. Our data elucidate a correlative link between central metabolic and regulatory pathways, and they suggest that the Gac system senses a blockage at the aconitase step of the tricarboxylic acid cycle, either through elevated citrate levels or a secondary metabolic effect of citrate accumulation, and responds by modulating carbon flow and various functions associated with host colonization, including bioluminescence. PMID:25402589

  12. Identification and Characterization of OscR, a Transcriptional Regulator Involved in Osmolarity Adaptation in Vibrio cholerae? †

    PubMed Central

    Shikuma, Nicholas J.; Yildiz, Fitnat H.

    2009-01-01

    Vibrio cholerae is a facultative human pathogen. In its aquatic habitat and as it passes through the digestive tract, V. cholerae must cope with fluctuations in salinity. We analyzed the genome-wide transcriptional profile of V. cholerae grown at different NaCl concentrations and determined that the expression of compatible solute biosynthesis and transporter genes, virulence genes, and genes involved in adhesion and biofilm formation is differentially regulated. We determined that salinity modulates biofilm formation, and this response was mediated through the transcriptional regulators VpsR and VpsT. Additionally, a transcriptional regulator controlling an osmolarity adaptation response was identified. This regulator, OscR (osmolarity controlled regulator), was found to modulate the transcription of genes involved in biofilm matrix production and motility in a salinity-dependent manner. oscR mutants were less motile and exhibited enhanced biofilm formation only under low-salt conditions. PMID:19329635

  13. Shallot (Allium ascalonicum L.) oil: Diallyl sulfide content and antimicrobial activity against food-borne pathogenic bacteria

    Microsoft Academic Search

    P. Rattanachaikunsopon; P. Phumkhachorn

    2009-01-01

    Shallot (Allium ascalonicum L.) oil was studied for its major diallyl sulfide content and its antimicrobial activity against food-borne pathogenic bacteria including Bacillus cereus, Camplobacter jejuni, Escherichia coli O157:H7, Listeria monocytgenes, Salmonella enterica, Staphylococcus aureus, and Vibrio cholerae. The oil had a very low concentration of diallyl monosulfides (1.59%) in comparison with the other diallyl sulfides (24.66% for diallyl disulfide,

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

    PubMed Central

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

    2014-01-01

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

  15. EXAMINING THE PRESENCE OF A COLD SHOCK RESPONSE IN THE HUMAN PATHOGEN, VIBRIO VULNIFICUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many aspects of our environment are continually changing whether on a daily cycle, or randomly. This continually changing environment creates a need for responsive mechanisms in all living organisms. The most basic physiological stress responses generally involve the induction of numerous interact...

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed Central

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

    2012-01-01

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

  18. Vibrio cholerae T3SS effector VopE modulates mitochondrial dynamics and innate immune signaling by targeting Miro GTPases.

    PubMed

    Suzuki, Masato; Danilchanka, Olga; Mekalanos, John J

    2014-11-12

    The cellular surveillance-activated detoxification and defenses (cSADD) theory postulates the presence of host surveillance mechanisms that monitor the integrity of common cellular processes and components targeted by pathogen effectors. Being organelles essential for multiple cellular processes, including innate immune responses, mitochondria represent an attractive target for pathogens. We describe a Vibrio cholerae Type 3 secretion system effector VopE that localizes to mitochondria during infection and acts as a specific GTPase-activating protein to interfere with the function of mitochondrial Rho GTPases Miro1 and Miro2. Miro GTPases modulate mitochondrial dynamics and interfering with this functionality effectively blocks innate immune responses that presumably require mitochondria as signaling platforms. Our data indicate that interference with mitochondrial dynamics may be an unappreciated strategy that pathogens use to block host innate immune responses that would otherwise control these bacterial infections. VopE might represent a bacterial effector that targets the cSADD surveillance response. PMID:25450857

  19. A New Membrane Lipid Raft Gene SpFLT-1 Facilitating the Endocytosis of Vibrio alginolyticus in the Crab Scylla paramamosain

    PubMed Central

    Chen, Fangyi; Bo, Jun; Ma, Xiaowan; Dong, Lixia; Shan, Zhongguo; Cui, Qian; Chen, Huiyun; Wang, Kejian

    2015-01-01

    Pathogens can enter their host cells by way of endocytosis in which the membrane lipid raft gene flotillins are probably involved in the invasion process and this is an important way to cause infection. In this study, a new gene SpFLT-1 was identified in Scylla paramamosain, which shared high identity with the flotillin-1 of other species. The SpFLT-1 gene was widely distributed in tissues and showed the highest level of mRNA transcripts in the hemocytes. This gene might be a maternal gene based on the evident results that it was highly expressed in maternal ovaries and in the early developmental stages of the zygote and early embryo stage whereas it gradually decreased in zoea 1. SpFLT-1 positively responded to the challenge of Vibrio alginolyticus with a significantly increased level of mRNA expression in the hemocytes and gills at 3 hours post infection (hpi). The SpFLT-1 protein was detected densely in the same fraction layer where the Vibrio protein was most present in the hemocytes and gills at 3 hpi. Furthermore, it was found that the expression of SpFLT-1 decreased to the base level following disappearance of the Vibrio protein at 6 hpi in the gills. Silencing SpFLT-1 inhibited the endocytosis rate of V. alginolyticus but overexpression of the gene could facilitate bacterial entry into the epithelioma papulosum cyprinid cells. Our study indicated that SpFLT-1 may act as a key protein involved in the process of bacterial infection and this sheds light on clarifying the pathogenesis of pathogens infecting S. paramamosain. PMID:26186350

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

    PubMed Central

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

    2014-01-01

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

  1. Polyphyly of non-bioluminescent Vibrio fischeri sharing a lux-locus deletionemi_2608 655..668

    E-print Network

    McFall-Ngai, Margaret

    Polyphyly of non-bioluminescent Vibrio fischeri sharing a lux-locus deletionemi_2608 655..668 M. S to be composed only of bioluminescent strains is Vibrio fischeri. Why, in all environmental samples analysed

  2. Bacteriocin production by indigenous marine catfish associated Vibrio spp.

    PubMed

    Zai, Arsalan Saeed; Ahmad, Samia; Rasool, Sheikh Ajaz

    2009-04-01

    Fifty strains of genus Vibrio were isolated (identified) from healthy and diseased marine catfish(es). The isolates were screened for bacteriocin (vibriocin) production. About 32% isolates were found bacteriocin producers. The best producer was identified as Vibrio anguillarum AVP10. The maximum production of vibriocin AVP10 was manifested at 29 degrees C at pH 7, after 18-20 h of incubation. Vibriocin activity was enhanced in the presence of citrate-phosphate buffer. The vibriocin AVP10 withstands autoclaving temperature and showed activity even after prolonged chloroform treatment. Proteolytic enzymes inhibited its activity, while lipolytic enzyme had no effect. It was found bioactive only against intrageneric bacterial strains. Mode of action of vibriocin AVP10 varies with the indicator (sensitive) culture used i.e. bactericidal effects was exerted against V. anguillarum AVS9 while bacteriostatic effect was shown against entero-toxigenic E. coli. PMID:19339226

  3. Motility as a virulence factor for Vibrio cholerae.

    PubMed Central

    Guentzel, M N; Berry, L J

    1975-01-01

    The ability of motile strains of the Ogawa and Inaba serotypes of classical Vibrio cholerae and of the El Tor biotypes to kill suckling mice after oral challenge with 10-8 colony-forming units (representing at least 100 to 1,000 minimal lethal doses) was compared to that of nonmotile derivatives of the same strains. Loss of motility, in each case, resulted in a marked reduction in virulence. The mortality (at 36 h) caused by 10 of the 13 nonmotile strains was 32% or less. whereas the motile wild-type strains resulted in nearly 100% deaths. The reduced virulence of the nonmotile strains was associated with reduced capacity to adsorb to the surface of segments of mouse intestine. The mutants were tested for alterations in enterotoxin production and surface properties. The results suggest that motility may contribute to virulence by increasing the chance for association of the vibrios with the intestinal mucosa. PMID:1091563

  4. PATHOGENS: VIEWS OF EPA'S PATHOGEN EQUIVALENCY COMMITTEE

    EPA Science Inventory

    This presentation reviews the pathogenic microorganisms that may be found in municipal sewage sludge and the commonly employed Class A and B processes for controlling pathogens. It notes how extensively they are used and discusses issues and concerns with their application. Pre...

  5. Cyclic Diguanylate Regulates Vibrio cholerae Virulence Gene Expression

    Microsoft Academic Search

    Anna D. Tischler; Andrew Camilli

    2005-01-01

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

  6. Filamentous phage fs1 of Vibrio cholerae O139.

    PubMed

    Nakasone, N; Honma, Y; Toma, C; Yamashiro, T; Iwanaga, M

    1998-01-01

    Filamentous phage, fs1, was obtained from Vibrio cholerae O139. The lysogenized strains produced a large amount of fs1 phage in the culture supernatant. This phage was previously reported as novel fimbriae of that organism. The genome of the phage was a 6.5 kb single-stranded DNA. The capsid of fsl consists of a small molecule peptide (about 2.5 kDa). PMID:9570290

  7. Quartz crystal microbalance detection of Vibrio cholerae O139 serotype.

    PubMed

    Carter, R M; Mekalanos, J J; Jacobs, M B; Lubrano, G J; Guilbault, G G

    1995-11-16

    A piezoelectric (PZ) quartz crystal microbalance (QCM) biosensor for the rapid detection of Vibrio cholerae serotype O139 has been developed. The antibody to this serotype was immobilized on the gold transducer surface of a 10 MHz AT cut PZ crystal. Solutions containing known antigen concentrations were then incubated for 1 h on the antibody-bound transducer. The biosensor was able to detect 10(5) cells per ml of O139 versus a background of O1 (Ogawa) serotype. PMID:7490448

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

    Microsoft Academic Search

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

    1984-01-01

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

  9. Siderophore production by New Zealand strains of Vibrio anguillarum

    Microsoft Academic Search

    Vivien Pybus; Margaret W. Loutit; John R. Tagg

    1994-01-01

    New Zealand isolates of Vibrio anguillarum from water, sediments and healthy salmon were tested for their ability to grow under iron?limiting conditions and to produce sidero?phores. Their growth in the presence of the iron chelator ethylenediamine?di(o?hydroxyphenyl?acetic acid) (EDDA) suggested they could withstand conditions of iron limitation, with a 200 ?M EDDA MIC recorded for the majority of strains. A positive

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

    PubMed Central

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

    2013-01-01

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

  11. Populations, not clones, are the unit of vibrio pathogenesis in naturally infected oysters.

    PubMed

    Lemire, Astrid; Goudenège, David; Versigny, Typhaine; Petton, Bruno; Calteau, Alexandra; Labreuche, Yannick; Le Roux, Frédérique

    2015-07-01

    Disease in oysters has been steadily rising over the past decade, threatening the long-term survival of commercial and natural stocks. Our understanding and management of such diseases are of critical importance as aquaculture is an important aspect of dealing with the approaching worldwide food shortage. Although some bacteria of the Vibrio genus isolated from diseased oysters have been demonstrated to be pathogenic by experimental infection, direct causality has not been established. Little is known about the dynamics of how the bacterial population hosted by oysters changes during disease progression. Combining experimental ecology, a high-throughput infection assay and genome sequencing, we show that the onset of disease in oysters is associated with progressive replacement of diverse benign colonizers by members of a phylogenetically coherent virulent population. Although the virulent population is genetically diverse, all members of that population can cause disease. Comparative genomics across virulent and nonvirulent populations identified candidate virulence factors that were clustered in population-specific genomic regions. Genetic analyses revealed that one gene for a candidate virulent factor, a putative outer membrane protein, is necessary for infection of oysters. Finally, analyses of oyster mortality following experimental infection suggest that disease onset can be facilitated by the presence of nonvirulent strains. This is a new form of polymicrobial disease, in which nonpathogenic strains contribute to increase mortality. PMID:25489729

  12. Quantifying viable Vibrio parahaemolyticus and Listeria monocytogenes simultaneously in raw shrimp.

    PubMed

    Zhang, Zhaohuan; Liu, Haiquan; Lou, Yang; Xiao, Lili; Liao, Chao; Malakar, Pradeep K; Pan, Yingjie; Zhao, Yong

    2015-08-01

    A novel TaqMan-based multiplex real-time PCR method combined with propidium monoazide (PMA) treatment was firstly developed for the simultaneous quantification of viable Vibrio parahaemolyticus and Listeria monocytogenes in raw shrimp. The optimization of PMA concentration showed that 100 ?M was considered optimal to effectively inhibit 10(8) CFU/mL dead cells of both bacteria. The high specificity of this method was confirmed on tests using 96 target and non-target strains. The optimized assay could detect as low as 10(1)-10(2) CFU/g of each strain on the artificially contaminated shrimp, and its amplification efficiencies were up to 100 and 106 % for V. parahaemolyticus and L. monocytogenes, respectively. Furthermore, this assay has been successfully applied to describe the behavior of these two pathogens in raw shrimps stored at 4 °C. In conclusion, this PMA TaqMan-based multiplex real-time PCR technique, where the whole procedure takes less than 5 h, provides an effective and rapid tool for monitoring contamination of viable V. parahaemolyticus and L. monocytogenes in seafood, improving seafood safety and protecting public health. PMID:26048473

  13. Uptake and retention of Vibrio cholerae O1 in the Eastern oyster, Crassostrea virginica.

    PubMed Central

    Murphree, R L; Tamplin, M L

    1995-01-01

    Vibrio cholerae 01, the causative agent of cholera, is known to persist in estuarine environments as endogenous microflora. The recent introduction of V. cholerae 01 into estuaries of the North and South American continents has stimulated the need to determine the effect of controlled purification on reducing this pathogen in edible molluscan shellfish. Experiments defined parameters for the uptake and retention of V. cholerae 01 in tissues of Crassostrea virginica, and these parameters were compared with those for Escherichia coli and Salmonella tallahassee, bacteria which are usually eliminated from moderately contaminated shellfish within 48 h. Oysters accumulated greater concentrations of V. cholerae 01 than E. coli and S. tallahassee. When V. cholerae 01 was exposed to controlled purification at 15, 19 and 25 degrees C over 48 h, it persisted in oysters at markedly higher levels than E. coli and S. tallahassee. The concentration of a V. cholerae 01-specific agglutinin did not positively correlate with the uptake or retention of V. cholerae 01. These data show that state and federally approved controlled purification techniques are not effective at reducing V. cholerae 01 in oysters. PMID:7487003

  14. Direct plating procedure for enumerating Vibrio vulnificus in oysters (Crassostrea virginica).

    PubMed Central

    Miceli, G A; Watkins, W D; Rippey, S R

    1993-01-01

    A procedure for enumerating and identifying Vibrio vulnificus in oysters was developed and evaluated. This method consists of growth on a direct plating medium (VVE medium) for isolating the organism from shellfish tissues, followed by biochemical tests for differentiating and identifying presumptively positive isolates. Densities of V. vulnificus are reliably obtained in 2 to 4 days, and as few as 10 culturable cells per 100 g can be identified. The procedure was evaluated by using a DNA probe technique specific for the cytotoxin-hemolysin gene of V. vulnificus and gas chromatographic analysis of the fatty acid contents of positive isolates. Only 3.2 and 0.4% of the isolates gave false-positive and false-negative results, respectively. The average level of recovery on VVE medium for 33 strains, including both clinical and environmental isolates, was 92% of the level of recovery obtained with brain heart infusion agar supplemented with 1% NaCl. The densities of V. vulnificus in oyster homogenates and individual oysters harvested from gulf and Atlantic coastal waters revealed that seasonally high levels occurred. The VVE medium procedure facilitated enumeration of this pathogen in molluscan shellfish and had a distinct advantage over the widely used most-probable-number procedure for V. vulnificus enumeration, which requires 5 to 7 days and often gives improbable and imprecise results. PMID:8285658

  15. Localization of Ubiquinone-8 in the Na+-pumping NADH:Quinone Oxidoreductase from Vibrio cholerae*

    PubMed Central

    Casutt, Marco S.; Nedielkov, Ruslan; Wendelspiess, Severin; Vossler, Sara; Gerken, Uwe; Murai, Masatoshi; Miyoshi, Hideto; Möller, Heiko M.; Steuber, Julia

    2011-01-01

    Na+ is the second major coupling ion at membranes after protons, and many pathogenic bacteria use the sodium-motive force to their advantage. A prominent example is Vibrio cholerae, which relies on the Na+-pumping NADH:quinone oxidoreductase (Na+-NQR) as the first complex in its respiratory chain. The Na+-NQR is a multisubunit, membrane-embedded NADH dehydrogenase that oxidizes NADH and reduces quinone to quinol. Existing models describing redox-driven Na+ translocation by the Na+-NQR are based on the assumption that the pump contains four flavins and one FeS cluster. Here we show that the large, peripheral NqrA subunit of the Na+-NQR binds one molecule of ubiquinone-8. Investigations of the dynamic interaction of NqrA with quinones by surface plasmon resonance and saturation transfer difference NMR reveal a high affinity, which is determined by the methoxy groups at the C-2 and C-3 positions of the quinone headgroup. Using photoactivatable quinone derivatives, it is demonstrated that ubiquinone-8 bound to NqrA occupies a functional site. A novel scheme of electron transfer in Na+-NQR is proposed that is initiated by NADH oxidation on subunit NqrF and leads to quinol formation on subunit NqrA. PMID:21885438

  16. Functional interaction analysis of GM1-related carbohydrates and Vibrio cholerae toxins using carbohydrate microarray.

    PubMed

    Kim, Chang Sup; Seo, Jeong Hyun; Cha, Hyung Joon

    2012-08-01

    The development of analytical tools is important for understanding the infection mechanisms of pathogenic bacteria or viruses. In the present work, a functional carbohydrate microarray combined with a fluorescence immunoassay was developed to analyze the interactions of Vibrio cholerae toxin (ctx) proteins and GM1-related carbohydrates. Ctx proteins were loaded onto the surface-immobilized GM1 pentasaccharide and six related carbohydrates, and their binding affinities were detected immunologically. The analysis of the ctx-carbohydrate interactions revealed that the intrinsic selectivity of ctx was GM1 pentasaccharide ? GM2 tetrasaccharide > asialo GM1 tetrasaccharide ? GM3trisaccharide, indicating that a two-finger grip formation and the terminal monosaccharides play important roles in the ctx-GM1 interaction. In addition, whole cholera toxin (ctxAB(5)) had a stricter substrate specificity and a stronger binding affinity than only the cholera toxin B subunit (ctxB). On the basis of the quantitative analysis, the carbohydrate microarray showed the sensitivity of detection of the ctxAB(5)-GM1 interaction with a limit-of-detection (LOD) of 2 ng mL(-1) (23 pM), which is comparable to other reported high sensitivity assay tools. In addition, the carbohydrate microarray successfully detected the actual toxin directly secreted from V. cholerae, without showing cross-reactivity to other bacteria. Collectively, these results demonstrate that the functional carbohydrate microarray is suitable for analyzing toxin protein-carbohydrate interactions and can be applied as a biosensor for toxin detection. PMID:22770420

  17. Ultrasensitive detection of Vibrio cholerae O1 using microcantilever-based biosensor with dynamic force microscopy.

    PubMed

    Sungkanak, Usa; Sappat, Assawapong; Wisitsoraat, Anurat; Promptmas, Chamras; Tuantranont, Adisorn

    2010-10-15

    This work presents the first demonstration of a cantilever based cholerae sensor. Dynamic force microscopy within atomic force microscope (AFM) is applied to measure the cantilever's resonance frequency shift due to mass of cell bound on microcantilever surface. The Vibrio cholerae O1, a food and waterborne pathogen that caused cholera disease in human, is a target bacterium cell of interest. Commercial gold-coated AFM microcantilevers are immobilized with monoclonal antibody (anti-V. cholerae O1) by self-assembled monolayer method. V. cholerae O1 detection experiment is then conducted in concentrations ranging from 1×10(3) to 1×10(7) CFU/ml. The microcantilever-based sensor has a detection limit of ?1×10(3) CFU/ml and a mass sensitivity, ?m/?F, of ?146.5 pg/Hz, which is at least two orders of magnitude lower than other reported techniques and sufficient for V. cholerae detection in food products without pre-enrichment steps. In addition, V. cholerae O1 antigen-antibody binding on microcanilever is confirmed by scanning electron microscopy. The results demonstrate that the new biosensor is promising for high sensitivity, uncomplicated and rapid detection of V. cholerae O1. PMID:20637589

  18. In silico phylogenetic analysis of Vibrio cholerae isolates based on three housekeeping genes.

    PubMed

    Farhadi, Tayebeh; Nezafat, Navid; Ghasemi, Younes

    2015-01-01

    Vibrio cholera, a gram-negative bacterium, has been categorised into clinical and environmental species. Phylogenetic studies have been performed to investigate the relationships of the V. cholerae populations in worldwide. In this study, phylogenetic relationship between V. cholerae isolates from Iran and other regions of the world was determined, based on three housekeeping genes analysis. Results for Iranian strains showed that congruency of asd and hlyA phylogenetic trees were remarkably higher than recA tree. Iranian strains displayed 2-3%, 1-14% and 3-5% deference in asd, hlyA and recA nucleotide sequences, respectively. Sequence similarity degrees were variable between Iranian and other region's strains. Furthermore, the non-congruence in the phylogeny of the pathogenic clones in cladograms is probably due to horizontal gene transfer. Finally, results of this study suggest that monitoring of surface waters for housekeeping genes of V. cholerae in the cholera endemic areas may be valuable for forecasting the expected cholera outbreaks. PMID:25869320

  19. In Silico Structural and Functional Annotation of Hypothetical Proteins of Vibrio cholerae O139.

    PubMed

    Islam, Md Saiful; Shahik, Shah Md; Sohel, Md; Patwary, Noman I A; Hasan, Md Anayet

    2015-06-01

    In developing countries threat of cholera is a significant health concern whenever water purification and sewage disposal systems are inadequate. Vibrio cholerae is one of the responsible bacteria involved in cholera disease. The complete genome sequence of V. cholerae deciphers the presence of various genes and hypothetical proteins whose function are not yet understood. Hence analyzing and annotating the structure and function of hypothetical proteins is important for understanding the V. cholerae. V. cholerae O139 is the most common and pathogenic bacterial strain among various V. cholerae strains. In this study sequence of six hypothetical proteins of V. cholerae O139 has been annotated from NCBI. Various computational tools and databases have been used to determine domain family, protein-protein interaction, solubility of protein, ligand binding sites etc. The three dimensional structure of two proteins were modeled and their ligand binding sites were identified. We have found domains and families of only one protein. The analysis revealed that these proteins might have antibiotic resistance activity, DNA breaking-rejoining activity, integrase enzyme activity, restriction endonuclease, etc. Structural prediction of these proteins and detection of binding sites from this study would indicate a potential target aiding docking studies for therapeutic designing against cholera. PMID:26175663

  20. Identification of genes induced in Vibrio cholerae in a dynamic biofilm system

    PubMed Central

    Seper, Andrea; Pressler, Katharina; Kariisa, Ankunda; Haid, Andrea G.; Roier, Sandro; Leitner, Deborah R.; Reidl, Joachim; Tamayo, Rita; Schild, Stefan

    2014-01-01

    The facultative human pathogen Vibrio cholerae, the causative agent of the severe secretory diarrheal disease cholera, persists in its aquatic reservoirs in biofilms during interepidemic periods. Biofilm is a likely form in which clinically relevant V. cholerae is taken up by humans, providing an infective dose. Thus, a better understanding of biofilm formation of V. cholerae is relevant for the ecology and epidemiology of cholera as well as a target to control the disease. Most previous studies have investigated static biofilms of V. cholerae and elucidated structural prerequisites like flagella, pili and a biofilm matrix including extracellular DNA, numerous matrix proteins and exopolysaccharide, as well as the involvement of regulatory pathways like two-component systems, quorum sensing and c-di-GMP signaling. However, aquatic environments are more likely to reflect an open, dynamic system. Hence, we used a biofilm system with constant medium flow and a temporal controlled reporter-system of transcription to identify genes induced during dynamic biofilm formation. We identified genes known or predicted to be involved in c-di-GMP signaling, motility and chemotaxis, metabolism, and transport. Subsequent phenotypic characterization of mutants with independent mutations in candidate dynamic biofilm-induced genes revealed novel insights into the physiology of static and dynamic biofilm conditions. The results of this study also reinforce the hypotheses that distinct differences in regulatory mechanisms governing biofilm development are present under dynamic conditions compared to static conditions. PMID:24962154

  1. The virulence phenotypes and molecular epidemiological characteristics of Vibrio fluvialis in China

    PubMed Central

    2013-01-01

    Background Vibrio fluvialis is considered to be an emerging foodborne pathogen and has been becoming a high human public health hazard all over the world, especially in coastal areas of developing countries and regions with poor sanitation. The distribution of virulence factors, microbiological and molecular epidemiological features of V. fluvialis isolates in China remains to be examined. Methods and results PCR targeted at the virulence determinants and phenotype tests including metabolism, virulence and antibiotic susceptibility were performed. Pulsed-field gel electrophoresis (PFGE) analysis was used to access the relatedness of isolates. A strain with deletion of the arginine dihydrolase system was first reported and proved in molecular level by PCR. Virulence genes vfh, hupO and vfpA were detected in all strains, the ability to produce hemolysin, cytotxin, protease and biofilm formation varied with strains. High resistance rate to ?-lactams, azithromycin and sulfamethoxazole were observed. Twenty-seven percent of test strains showed resistant to two and three antibiotics. PFGE analysis demonstrated great genetic heterogeneity of test V. fluvialis strains. Conclusion This study evaluated firstly the biological characteristics and molecular epidemiological features of V. fluvialis in China. Some uncommon biochemical characteristics were found. Virulence genes were widely distributed in the isolates from patient and seafood sources, and the occurrence of virulence phenotypes varied with strains. Continued and enhanced laboratory based-surveillance is needed in the future together with systematically collection of the epidemiological information of the cases or the outbreaks. PMID:23522652

  2. Toxigenic Vibrio cholerae identified in estuaries of Tanzania using PCR techniques.

    PubMed

    Dalusi, Lucy; Lyimo, Thomas J; Lugomela, Charles; Hosea, Ken M M; Sjöling, Sara

    2015-03-01

    The current study assessed the occurrence of the Vibrio cholerae serogroups O1 and O139 in environmental samples along salinity gradients in three selected estuaries of Tanzania both through culture independent methods and by cultured bacteria. Occurrence of V. cholerae was determined by PCR targeting the V. cholerae outer membrane protein gene ompW. Furthermore, the presence of toxigenic strains and serogroups O1 and O139 was determined using multiplex PCR with specific primers targeting the cholera toxin gene subunit A, ctxA, and serotype specific primers, O1-rfb and O139-rfb, respectively. Results showed that V. cholerae occurred in approximately 10% (n = 185) of both the environmental samples and isolated bacteria. Eight of the bacteria isolates (n = 43) were confirmed as serogroup O1 while one belonged to serogroup O139, the first reported identification of this epidemic strain in East African coastal waters. All samples identified as serogroup O1 or O139 and a number of non-O1/O139 strains were ctxA positive. This study provides in situ evidence of the presence of pathogenic V. cholerae O1 and O139 and a number of V. cholerae non-O1/O139 that carry the cholera toxin gene in estuaries along the coast of Tanzania. PMID:25743072

  3. In Silico Structural and Functional Annotation of Hypothetical Proteins of Vibrio cholerae O139

    PubMed Central

    Islam, Md. Saiful; Shahik, Shah Md.; Sohel, Md.; Patwary, Noman I. A.

    2015-01-01

    In developing countries threat of cholera is a significant health concern whenever water purification and sewage disposal systems are inadequate. Vibrio cholerae is one of the responsible bacteria involved in cholera disease. The complete genome sequence of V. cholerae deciphers the presence of various genes and hypothetical proteins whose function are not yet understood. Hence analyzing and annotating the structure and function of hypothetical proteins is important for understanding the V. cholerae. V. cholerae O139 is the most common and pathogenic bacterial strain among various V. cholerae strains. In this study sequence of six hypothetical proteins of V. cholerae O139 has been annotated from NCBI. Various computational tools and databases have been used to determine domain family, protein-protein interaction, solubility of protein, ligand binding sites etc. The three dimensional structure of two proteins were modeled and their ligand binding sites were identified. We have found domains and families of only one protein. The analysis revealed that these proteins might have antibiotic resistance activity, DNA breaking-rejoining activity, integrase enzyme activity, restriction endonuclease, etc. Structural prediction of these proteins and detection of binding sites from this study would indicate a potential target aiding docking studies for therapeutic designing against cholera. PMID:26175663

  4. Biocompatible capped iron oxide nanoparticles for Vibrio cholerae detection.

    PubMed

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

    2015-05-01

    We report the studies relating to fabrication of an efficient immunosensor for Vibrio cholerae detection. Magnetite (iron oxide (Fe(3)O(4))) 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 Fe(3)O(4) and CA-Fe(3)O(4)/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 Fe(3)O(4), CA-Fe(3)O(4) 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 (Fe(3)O(4)) and 189.51 nm (CA-Fe(3)O(4)) by DLS measurement. The results of electrochemical response studies of the fabricated BSA/Ab/CA-Fe(2)O(3)/ITO immunosensor exhibits a good detection range of 12.5-500 ng mL(-1) with a low detection limit of 0.32 ng mL(-1), sensitivity 0.03 ?/ng ml(-1) cm(-2), and reproducibility more than 11 times. PMID:25850702

  5. Distribution ofVibrio cholerae in two Florida estuaries.

    PubMed

    Hood, M A; Ness, G E; Rodrick, G E; Blake, N J

    1983-04-01

    The distribution ofVibrio cholerae was examined in 2 Florida estuaries, Apalachicola and Tampa Bay.Vibrio cholerae serotype non-01 was the most abundant serotype, being isolated from 45% of the oyster samples, 30% of the sediments, 50% of the waters, and 75% of the blue crabs.Vibrio cholerae serotype 01 was isolated from only one oyster sample. Strong linear correlations betweenV. cholerae and temperature, salinity, or the other physical/chemical parameters measured,Escherichia coli, or fecal coliforms were not observed, but a range of temperatures and salinities appeared relevant to the distribution of the organism. The organism was present in the highest concentrations when salinities were 10‰-25‰ and temperatures were 20‡C-35‡C.In vitro growth curves of 95V. cholerae environmental isolates further supported that 10‰-25‰ was an ideal salinity range for the organisms. The results suggest thatV. cholerae is a widely distributed organism in the nutrient-rich warm waters of the Gulf Coast estuaries. PMID:24221617

  6. Vibrio factors cause rapid fluid accumulation in suckling mice.

    PubMed Central

    Nishibuchi, M; Seidler, R J; Rollins, D M; Joseph, S W

    1983-01-01

    Non-O-1 and O-1 Vibrio cholerae and Vibrio fluvialis isolated from clinical and environmental sources were examined for virulence factor production in 3-day-old suckling mice and in Y-1 tissue culture. The responses of the suckling mice to intragastrically administered bacterial cultures were measured by intestinal fluid accumulation (FA), diarrhea, and mortality. Regardless of the O-serovar, source of isolation, or ability to produce cholera toxin, all strains of V. cholerae stimulated increased FA, which was measurable in the mice at 4 h post-inoculation. The factor(s) causing these symptoms was found to be distinct from cholera toxin by the kinetics of FA and serological difference from cholera toxin based on in vivo neutralization tests. In most instances, FA was followed by high rates of mortality. Y-1 mouse adrenal tumor cell assays also showed that many V. cholerae produced extracellular heat-labile cytotoxic factor(s), and many cholera toxin-negative strains also caused a cytotonic-like morphological response. The majority of V. fluvialis strains produced smaller amounts of cytotoxic factor(s) but no cytotoxic reactions. The factor which stimulates rapid FA in suckling mice could be one of several virulence-associated factors contributing to diarrheal disease by nontoxigenic vibrios, but this is not verified at present. PMID:6852913

  7. OpaR Controls a Network of Downstream Transcription Factors in Vibrio parahaemolyticus BB22OP

    PubMed Central

    Kernell Burke, Alison; Guthrie, Leah T. C.; Modise, Thero; Cormier, Guy; Jensen, Roderick V.; McCarter, Linda L.; Stevens, Ann M.

    2015-01-01

    Vibrio parahaemolyticus is an emerging world-wide human pathogen that is associated with food-borne gastroenteritis when raw or undercooked seafood is consumed. Expression of virulence factors in this organism is modulated by the phenomenon known as quorum sensing, which permits differential gene regulation at low versus high cell density. The master regulator of quorum sensing in V. parahaemolyticus is OpaR. OpaR not only controls virulence factor gene expression, but also the colony and cellular morphology associated with growth on a surface and biofilm formation. Whole transcriptome Next Generation sequencing (RNA-Seq) was utilized to determine the OpaR regulon by comparing strains BB22OP (opaR+, LM5312) and BB22TR (?opaR1, LM5674). This work, using the published V. parahaemolyticus BB22OP genome sequence, confirms and expands upon a previous microarray analysis for these two strains that used an Affymetrix GeneChip designed from the closely related V. parahaemolyticus RIMD2210633 genome sequence. Overall there was excellent correlation between the microarray and RNA-Seq data. Eleven transcription factors under OpaR control were identified by both methods and further confirmed by quantitative reverse transcription PCR (qRT-PCR) analysis. Nine of these transcription factors were demonstrated to be direct OpaR targets via in vitro electrophoretic mobility shift assays with purified hexahistidine-tagged OpaR. Identification of the direct and indirect targets of OpaR, including small RNAs, will enable the construction of a network map of regulatory interactions important for the switch between the nonpathogenic and pathogenic states. PMID:25901572

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

    PubMed Central

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

    2012-01-01

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

  9. Vibrio cholerae cytolysin recognizes the heptasaccharide core of complex N-glycans with nanomolar affinity.

    PubMed

    Levan, Sophia; De, Swastik; Olson, Rich

    2013-03-11

    Pathogens selectively target host cells using adhesion molecules and secreted virulence factors that may utilize protein, lipid, or carbohydrate ligands on the cell surface. The human intestinal pathogen Vibrio cholerae secretes a pore-forming toxin, V.cholerae cytolysin (VCC), which contains two domains that are structurally similar to known carbohydrate-binding proteins. These tandem domains are attached to the carboxy-terminus of the cytolytic domain and contain a ?-trefoil fold and a ?-prism fold. VCC has been shown to bind glycosylated proteins, and removal of the ?-prism domain leads to a large decrease in lytic activity against rabbit erythrocytes. Despite these clues, the identity of the glycan receptors of VCC and the role of glycan binding in toxin activity remain unknown. To better understand this specificity, we used a combination of structural and functional approaches to characterize the carbohydrate-binding activity of the VCC toxin. We first probed the monosaccharide-binding activity of VCC and demonstrated that the toxin exhibits millimolar affinity for aldohexoses. To understand this specificity, we solved the crystal structure of the VCC ?-prism domain bound to methyl-?-mannose. Next, we utilized a mammalian glycan screen to determine that the ?-prism domain preferentially binds complex N-glycans with a heptasaccharide GlcNAc(4)Man(3) core (NGA2). Fluorescence anisotropy and surface plasmon resonance indicated an approximately 100-nM affinity of the ?-prism domain for the heptasaccharide core. Our results suggest that carbohydrate-binding domains on the VCC toxin facilitate high-affinity targeting of mammalian cell membranes, which may contribute to the ability of VCC to lyse cells at picomolar concentrations. PMID:23274141

  10. Long-term study of Vibrio parahaemolyticus prevalence and distribution in New Zealand shellfish.

    PubMed

    Cruz, C D; Hedderley, D; Fletcher, G C

    2015-04-01

    The food-borne pathogen Vibrio parahaemolyticus has been reported as being present in New Zealand (NZ) seawaters, but there have been no reported outbreaks of food-borne infection from commercially grown NZ seafood. Our study determined the current incidence of V. parahaemolyticus in NZ oysters and Greenshell mussels and the prevalence of V. parahaemolyticus tdh and trh strains. Pacific (235) and dredge (21) oyster samples and mussel samples (55) were obtained from commercial shellfish-growing areas between December 2009 and June 2012. Total V. parahaemolyticus numbers and the presence of pathogenic genes tdh and trh were determined using the FDA most-probable-number (MPN) method and confirmed using PCR analysis. In samples from the North Island of NZ, V. parahaemolyticus was detected in 81% of Pacific oysters and 34% of mussel samples, while the numbers of V. parahaemolyticus tdh and trh strains were low, with just 3/215 Pacific oyster samples carrying the tdh gene. V. parahaemolyticus organisms carrying tdh and trh were not detected in South Island samples, and V. parahaemolyticus was detected in just 1/21 dredge oyster and 2/16 mussel samples. Numbers of V. parahaemolyticus organisms increased when seawater temperatures were high, the season when most commercial shellfish-growing areas are not harvested. The numbers of V. parahaemolyticus organisms in samples exceeded 1,000 MPN/g only when the seawater temperatures exceeded 19°C, so this environmental parameter could be used as a trigger warning of potential hazard. There is some evidence that the total V. parahaemolyticus numbers increased compared with those reported from a previous 1981 to 1984 study, but the analytical methods differed significantly. PMID:25616790

  11. Isolation, characterization, and antibiotic resistance of Vibrio spp. in sea turtles from Northwestern Mexico

    PubMed Central

    Zavala-Norzagaray, Alan A.; Aguirre, A. Alonso; Velazquez-Roman, Jorge; Flores-Villaseñor, Héctor; León-Sicairos, Nidia; Ley-Quiñonez, C. P.; Hernández-Díaz, Lucio De Jesús; Canizalez-Roman, Adrian

    2015-01-01

    The aerobic oral and cloacal bacterial microbiota and their antimicrobial resistance were characterized for 64 apparently healthy sea turtles captured at their foraging grounds in Ojo de Liebre Lagoon (OLL), Baja California Sur (BCS), Mexico (Pacific Ocean) and the lagoon system of Navachiste (LSN) and Marine Area of Influence (MAI), Guasave, Sinaloa (Gulf of California). A total of 34 black turtles (Chelonia mydas agassizii) were sampled in OLL and eight black turtles and 22 olive ridley turtles (Lepidochelys olivacea) were sampled in LSN and MAI, respectively from January to December 2012. We isolated 13 different species of Gram-negative bacteria. The most frequently isolated bacteria were Vibrio alginolyticus in 39/64 (60%), V. parahaemolyticus in 17/64 (26%), and V. cholerae in 6/64 (9%). However, V. cholerae was isolated only from turtles captured from the Gulf of California (MAI). Among V. parahaemolyticus strains, six O serogroups and eight serovars were identified from which 5/17 (29.4%) belonged to the pathogenic strains (tdh+ gene) and 2/17 (11.7%) had the pandemic clone (tdh+ and toxRS/new+). Among V. cholerae strains, all were identified as non-O1/non-O139, and in 4/6 (66%) the accessory cholera enterotoxin gene (ace) was identified but without virulence gene zot, ctxA, and ctxB. Of the isolated V. parahaemolyticus, V. cholerae, and V. alginolyticus strains, 94.1, 33.4, and 100% demonstrated resistance to at least one commonly prescribed antibiotic (primarily to ampicillin), respectively. In conclusion, the presence of several potential (toxigenic) human pathogens in sea turtles may represent transmission of environmental microbes and a high-risk of food-borne disease. Therefore, based on the fact that it is illegal and unhealthy, we discourage the consumption of sea turtle meat or eggs in northwestern Mexico. PMID:26161078

  12. Zoonotic fecal pathogens and antimicrobial resistance in county fair animals.

    PubMed

    Roug, A; Byrne, B A; Conrad, P A; Miller, W A

    2013-05-01

    Livestock fairs present a unique opportunity for the public to experience close contact with animals, but may also expose people to zoonotic pathogens through contact with animal feces. The goal of this study was to screen cattle, sheep, goat, chicken, rabbit and horse feces from a livestock fair in California for the potentially zoonotic pathogens Escherichia coli O157:H7, Salmonella, Campylobacter, Vibrio, Cryptosporidium and Giardia spp., as well as determining the level of antimicrobial resistance in E. coli and Salmonella. Notably, E. coli O157:H7 was reported for the first time in a pig at a county fair in California. Campylobacter jejuni as well as Salmonella enterica serovars Derby and Thompson were also isolated from pigs, cattle, sheep, goats or chickens, whereas horses and rabbits were negative for all target pathogens. The prevalence of antimicrobial resistance as well as multi-drug resistance patterns were highest for E. coli and Salmonella spp. cultured from pigs and chickens, were generally widespread but at lower levels for other animal groups, and included resistance to ampicillin and streptomycin, two antimicrobial drugs of importance for human medicine. This study provides data that highlight the importance of practicing good hygiene in livestock fair settings to avoid transmission of zoonotic microbes, particularly pathogens with antimicrobial resistance, to fair visitors and among animal populations. PMID:23260373

  13. Enzymatic, outer membrane proteins and plasmid alterations of starved Vibrio parahaemolyticus and Vibrio alginolyticus cells in seawater

    Microsoft Academic Search

    Fethi Ben Abdallah; Héla Kallel; Amina Bakhrouf

    2009-01-01

    The marine bacteria Vibrio parahaemolyticus and V. alginolyticus were incubated in seawater for 8 months to evaluate their adaptative responses to starvation. The starved cells showed an\\u000a altered biochemical and enzymatic profiles, respectively, on Api 20E and Api ZYM systems and an evolution to the filterable\\u000a minicells state capable to pass membrane pore size 0.45 ?m. Outer membrane proteins patterns of stressed

  14. Localization and bacteriostasis of Vibrio introduced into the Pacific white shrimp, Litopenaeus vannamei

    E-print Network

    Burnett, Louis E.

    Localization and bacteriostasis of Vibrio introduced into the Pacific white shrimp, Litopenaeus a major role in bacterial uptake and bacteriostasis in penaeid shrimp. q 2005 Elsevier Ltd. All rights reserved. Keywords: Lymphoid organ; Vibrio; Real-time PCR; Penaeid shrimp; Decapod crustaceans

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

    EPA Science Inventory

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  17. Natural transformation of Vibrio cholerae as a tool - Optimizing the procedure

    Microsoft Academic Search

    Rasmus L. Marvig; Melanie Blokesch

    2010-01-01

    BACKGROUND: Vibrio cholerae gains natural competence upon growth on chitin. This allows the organism to take up free DNA from the environment and to incorporate it into its genome by homologous recombination. RESULTS: Making use of this developmental program in order to use it as a tool to genetically manipulate V. cholerae and potentially also others Vibrio species was envisaged.

  18. Immunological Biosensor for Detection of Vibrio cholerae O1in Environmental Water Samples

    Microsoft Academic Search

    M. K. Sharma; A. K. Goel; L. Singh; V. K. Rao

    2006-01-01

    Environmental surveillance for the presence of Vibrio cholerae O1 is of utmost importance for the effective public health protection of cholera. In the present study, an amperometric immunosensor was developed for detection of Vibrio cholerae in environmental samples by using disposable screen-printed electrodes (SPEs). For this purpose, the experiments done include fabrication of SPEs by using carbon ink, electrochemical characterization

  19. THE EVOLUTIONARY ECOLOGY OF A SEPIOLID SQUID-VIBRIO ASSOCIATION: FROM CELL TO ENVIRONMENT

    E-print Network

    McFall-Ngai, Margaret

    THE EVOLUTIONARY ECOLOGY OF A SEPIOLID SQUID-VIBRIO ASSOCIATION: FROM CELL TO ENVIRONMENT S the evolution of these beneficial partnerships. The symbiosis between sepiolid squids (Cephalopoda: Sepiolidae sepiolid squids (Cephalopoda: Sepiolidae), and luminous bacteria (from the genera Vibrio and Photobacterium

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

    PubMed

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

    2012-01-01

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

  1. Antibacterial Effect of Silver Nanoparticles Against Four Foodborne Pathogens

    PubMed Central

    Zarei, Mehdi; Jamnejad, Amirhesam; Khajehali, Elahe

    2014-01-01

    Background: There is increased demand for improved disinfection methods due to microorganisms resistant to multiple antimicrobial agents. Numerous types of disinfectants are available with different properties; but the proper disinfectant must be carefully selected for any specific application to obtain the desired antimicrobial effect. Objectives: Antimicrobial effect of a commercial nanosilver product, NanoCid® L2000, against some foodborne pathogens was evaluated. Materials and Methods: Minimum inhibitory concentrations (MIC) were determined by monitoring the growth of bacteria at 600 nm, after 24 hours incubation at 35°C. Minimum bactericidal concentrations (MBC) were determined based on 3 log decrease in the viable population of the pathogens after incubation of nutrient agar plates at 35°C for 24 hours. The required exposure time for 3 log reduction in the viable population of the tested pathogens was determined as the minimum exposure time for efficient bactericidal activity. Results: The MIC values of Ag NPs against tested pathogens were in the range of 3.12-6.25 µg/mL. While Listeria monocytogenes showed the MIC value of 6.25 µg/mL, Escherichia coli O157:H7, Salmonella typhimurium and Vibrio parahaemolyticus all showed the MIC values of 3.12 µg/mL. However, all the pathogens showed the same MBC value of 6.25 µg/mL. To obtain an efficient bactericidal activity against E. coli O157:H7 and S. typhimurium, the exposure time should be at least ca. 6 hours., while this time was ca. 5 hours for V. parahaemolyticus and ca. 7 hours for L. monocytogenes. Conclusions: Silver nanoparticles showed great antibacterial effectiveness on four important foodborne pathogens. Therefore, Ag NPs could be a good alternative for cleaning and disinfection of equipment and surfaces in food-related environments. PMID:25147658

  2. OmpU as a biomarker for rapid discrimination between toxigenic and epidemic Vibrio cholerae O1/O139 and non-epidemic Vibrio cholerae in a modified MALDI-TOF MS assay

    PubMed Central

    2014-01-01

    Background Cholera is an acute diarrheal disease caused by Vibrio cholerae. Outbreaks are caused by a genetically homogenous group of strains from serogroup O1 or O139 that are able to produce the cholera toxin. Rapid detection and identification of these epidemic strains is essential for an effective response to cholera outbreaks. Results The use of ferulic acid as a matrix in a new MALDI-TOF MS assay increased the measurable mass range of existing MALDI-TOF MS protocols for bacterial identification. The assay enabled rapid discrimination between epidemic V. cholerae O1/O139 strains and other less pathogenic V. cholerae strains. OmpU, an outer membrane protein whose amino acid sequence is highly conserved among epidemic strains of V. cholerae, appeared as a discriminatory marker in the novel MALDI-TOF MS assay. Conclusions The extended mass range of MALDI-TOF MS measurements obtained by using ferulic acid improved the screening for biomarkers in complex protein mixtures. Differences in the mass of abundant homologous proteins due to variation in amino acid sequences can rapidly be examined in multiple samples. Here, a rapid MALDI-TOF MS assay was developed that could discriminate between epidemic O1/O139 strains and other less pathogenic V. cholerae strains based on differences in mass of the OmpU protein. It appeared that the amino acid sequence of OmpU from epidemic V. cholerae O1/O139 strains is unique and highly conserved. PMID:24943244

  3. Novel genomic tools for specific and real-time detection of biothreat and frequently encountered foodborne pathogens.

    PubMed

    Woubit, Abdela; Yehualaeshet, Teshome; Habtemariam, Tsegaye; Samuel, Temesgen

    2012-04-01

    The bacterial genera Escherichia, Salmonella, Shigella, Vibrio, Yersinia, and Francisella include important food safety and biothreat agents. By extensive mining of the whole genome and protein databases of diverse, closely and distantly related bacterial species and strains, we have identified novel genome regions, which we utilized to develop a rapid detection platform for these pathogens. The specific genomic targets we have identified to design the primers in Francisella tularensis subsp. tularensis, F. tularensis subsp. novicida, Shigella dysenteriae, Salmonella enterica serovar Typhimurium, Vibrio cholerae, Yersinia pestis, and Yersinia pseudotuberculosis contained either known genes or putative proteins. Primer sets were designed from the target regions for use in real-time PCR assays to detect specific biothreat pathogens at species or strain levels. The primer sets were first tested by in silico PCR against whole-genome sequences of different species, subspecies, or strains and then by in vitro PCR against genomic DNA preparations from 23 strains representing six biothreat agents (Escherichia coli O157:H7 strain EDL 933, Shigella dysenteriae, S. enterica serovar Typhi, F. tularensis subsp. tularensis, V. cholerae, and Y. pestis) and six foodborne pathogens (Salmonella Typhimurium, Salmonella Saintpaul, Shigella sonnei, F. tularensis subsp. novicida, Vibrio parahaemolyticus, and Y. pseudotuberculosis). Each pathogen was specifically identifiable at the genus and species levels. Sensitivity assays performed with purified DNA showed the lowest detection limit of 128 fg of DNA/?l for F. tularensis subsp. tularensis. A preliminary test to detect Shigella organisms in a milk matrix also enabled the detection of 6 to 60 CFU/ml. These new tools could ultimately be used to develop platforms to simultaneously detect these pathogens. PMID:22488053

  4. Coral Pathogens Identified for White Syndrome (WS) Epizootics in the Indo-Pacific

    PubMed Central

    Sussman, Meir; Willis, Bette L.; Victor, Steven; Bourne, David G.

    2008-01-01

    Background White Syndrome (WS), a general term for scleractinian coral diseases with acute signs of advancing tissue lesions often resulting in total colony mortality, has been reported from numerous locations throughout the Indo-Pacific, constituting a growing threat to coral reef ecosystems. Methodology/Principal Findings Bacterial isolates were obtained from corals displaying disease signs at three WS outbreak sites: Nikko Bay in the Republic of Palau, Nelly Bay in the central Great Barrier Reef (GBR) and Majuro Atoll in the Republic of the Marshall Islands, and used in laboratory-based infection trials to satisfy Henle-Koch's postulates, Evan's rules and Hill's criteria for establishing causality. Infected colonies produced similar signs to those observed in the field following exposure to bacterial concentrations of 1×106 cells ml?1. Phylogenetic 16S rRNA gene analysis demonstrated that all six pathogens identified in this study were members of the ?-Proteobacteria family Vibrionacae, each with greater than 98% sequence identity with the previously characterized coral bleaching pathogen Vibrio coralliilyticus. Screening for proteolytic activity of more than 150 coral derived bacterial isolates by a biochemical assay and specific primers for a Vibrio family zinc-metalloprotease demonstrated a significant association between the presence of isolates capable of proteolytic activity and observed disease signs. Conclusion/Significance This is the first study to provide evidence for the involvement of a unique taxonomic group of bacterial pathogens in the aetiology of Indo-Pacific coral diseases affecting multiple coral species at multiple locations. Results from this study strongly suggest the need for further investigation of bacterial proteolytic enzymes as possible virulence factors involved in Vibrio associated acute coral infections. PMID:18560584

  5. Efficacy of neutral electrolyzed water for reducing pathogenic bacteria contaminating shrimp.

    PubMed

    Ratana-Arporn, Pattama; Jommark, Naruemon

    2014-12-01

    Pathogenic contamination is a food safety concern. This study was conducted to investigate the efficacy of neutral electrolyzed water (NEW) in killing pathogens, namely, Vibrio parahaemolyticus, Vibrio vulnificus, Salmonella Enteritidis, and Escherichia coli in shrimp. Pure cultures of each pathogen were submerged separately in NEW containing five different chlorine concentrations: 10, 30, 50, 70, and 100 ppm. For each concentration, three submersion times were tested: 1, 3, and 5 min. The population of V. parahaemolyticus was rapidly reduced even at low concentrations, but prolonged contact times caused only a slight reduction. V. vulnificus was gradually inhibited with increasing NEW concentrations and contact times. For the V. parahaemolyticus applications of 70 ppm for 5 min and of 100 ppm for 3 min, each eliminated 7 log CFU/ml. For V. vulnificus, applications of 50 ppm for 3 min and 100 ppm for 1 min, each eliminated 7 log CFU/ml. Salmonella Enteritidis and E. coli were slightly reduced by NEW. Applications of 50 ppm for 15 min and 10 ppm for 30 min completely eliminated 4.16 log CFU/g of V. parahaemolyticus in inoculated shrimp, while only a 1-log CFU/g reduction of V. vulnificus was detected. Soaking shrimp in 10 ppm NEW for 30 min did not affect its sensory quality. Our results suggest NEW could be an alternative sanitizer to improve the microbiological quality of seafood. PMID:25474069

  6. Vibrio vulnificus Biotype 3 Multifunctional Autoprocessing RTX Toxin Is an Adenylate Cyclase Toxin Essential for Virulence in Mice

    PubMed Central

    Ziolo, Kevin J.; Jeong, Hee-Gon; Kwak, Jayme S.; Yang, Shuangni; Lavker, Robert M.

    2014-01-01

    Vibrio vulnificus is an environmental organism that causes both food-borne and wound infections with high morbidity and mortality in humans. The annual incidence and global distribution of infections associated with this pathogen are increasing with climate change. In the late 1990s, an outbreak of tilapia-associated wound infections in Israel was linked to a previously unrecognized variant of V. vulnificus designated biotype 3. The sudden emergence and clonality of the outbreak suggest that this strain may be a true newly emergent pathogen with novel virulence properties compared to those of other V. vulnificus strains. In a subcutaneous infection model to mimic wound infection, the multifunctional autoprocessing RTX (MARTX) toxin of biotype 3 strains was shown to be an essential virulence factor contributing to highly inflammatory skin wounds with severe damage affecting every tissue layer. We conducted a sequencing-based analysis of the MARTX toxin and found that biotype 3 MARTX toxin has an effector domain structure distinct from that of either biotype 1 or biotype 2. Of the two new domains identified, a domain similar to Pseudomonas aeruginosa ExoY was shown to confer adenylate cyclase activity on the MARTX toxin. This is the first demonstration that the biotype 3 MARTX toxin is essential for virulence and that the ExoY-like MARTX effector domain is a catalytically active adenylate cyclase. PMID:24614656

  7. Anethole inhibits growth of recently emerged multidrug resistant toxigenic Vibrio cholerae O1 El Tor variant strains in vitro

    PubMed Central

    ZAHID, M. Shamim Hasan; AWASTHI, Sharda Prasad; HINENOYA, Atsushi; YAMASAKI, Shinji

    2015-01-01

    To search natural compounds having inhibitory effect on bacterial growth is important, particularly in view of growing multidrug resistant (MDR) strains of bacterial pathogens. Like other bacterial pathogens, MDR Vibrio cholerae, the causative agent of diarrheal disease cholera, is becoming a great concern. As an approach of searching new antimicrobial agents, here, we show that anethole, a well-studied natural component of sweet fennel and star anise seeds, could potentially inhibit the growth of MDR O1 El Tor biotype, the ongoing 7th cholera pandemic variant strains of toxigenic V. cholerae. The minimum inhibitory concentration (MIC) of anethole against diverse O1 El Tor biotype strains is evaluated as 200 µg/ml. Moreover, the effect of anethole is bactericidal and exerts rapid-killing action on V. cholerae cells. This study is the first report which demonstrates that anethole, purified from natural compound, is a potent inhibitor of growth of toxigenic V. cholerae. Our data suggest that anethole could be a potential antimicrobial drug candidate, particularly against MDR V. cholerae mediated infections. PMID:25648987

  8. Anethole inhibits growth of recently emerged multidrug resistant toxigenic Vibrio cholerae O1 El Tor variant strains in vitro.

    PubMed

    Zahid, M Shamim Hasan; Awasthi, Sharda Prasad; Hinenoya, Atsushi; Yamasaki, Shinji

    2015-06-01

    To search natural compounds having inhibitory effect on bacterial growth is important, particularly in view of growing multidrug resistant (MDR) strains of bacterial pathogens. Like other bacterial pathogens, MDR Vibrio cholerae, the causative agent of diarrheal disease cholera, is becoming a great concern. As an approach of searching new antimicrobial agents, here, we show that anethole, a well-studied natural component of sweet fennel and star anise seeds, could potentially inhibit the growth of MDR O1 El Tor biotype, the ongoing 7th cholera pandemic variant strains of toxigenic V. cholerae. The minimum inhibitory concentration (MIC) of anethole against diverse O1 El Tor biotype strains is evaluated as 200 µg/ml. Moreover, the effect of anethole is bactericidal and exerts rapid-killing action on V. cholerae cells. This study is the first report which demonstrates that anethole, purified from natural compound, is a potent inhibitor of growth of toxigenic V. cholerae. Our data suggest that anethole could be a potential antimicrobial drug candidate, particularly against MDR V. cholerae mediated infections. PMID:25648987

  9. Identification of a membrane-bound transcriptional regulator that links chitin and natural competence in Vibrio cholerae.

    PubMed

    Dalia, Ankur B; Lazinski, David W; Camilli, Andrew

    2014-01-01

    Vibrio cholerae is naturally competent when grown on chitin. It is known that expression of the major regulator of competence, TfoX, is controlled by chitin; however, the molecular mechanisms underlying this requirement for chitin have remained unclear. In the present study, we identify and characterize a membrane-bound transcriptional regulator that positively regulates the small RNA (sRNA) TfoR, which posttranscriptionally enhances tfoX translation. We show that this regulation of the tfoR promoter is direct by performing electrophoretic mobility shift assays and by heterologous expression of this system in Escherichia coli. This transcriptional regulator was recently identified independently and was named "TfoS" (S. Yamamoto et al., Mol. Microbiol., in press, doi:10.1111/mmi.12462). Using a constitutively active form of TfoS, we demonstrate that the activity of this regulator is sufficient to promote competence in V. cholerae in the absence of chitin. Also, TfoS contains a large periplasmic domain, which we hypothesized interacts with chitin to regulate TfoS activity. In the heterologous host E. coli, we demonstrate that chitin oligosaccharides are sufficient to activate TfoS activity at the tfoR promoter. Collectively, these data characterize TfoS as a novel chitin-sensing transcriptional regulator that represents the direct link between chitin and natural competence in V. cholerae. IMPORTANCE Naturally competent bacteria can take up exogenous DNA from the environment and integrate it into their genome by homologous recombination. This ability to take up exogenous DNA is shared by diverse bacterial species and serves as a mechanism to acquire new genes to enhance the fitness of the organism. Several members of the family Vibrionaceae become naturally competent when grown on chitin; however, a molecular understanding of how chitin activates competence is lacking. Here, we identify a novel membrane-bound transcriptional regulator that is required for natural transformation in the human pathogen Vibrio cholerae. We demonstrate that this regulator senses chitin oligosaccharides to activate the competence cascade, thus, uncovering the molecular link between chitin and natural competence in this Vibrio species. PMID:24473132

  10. Comparative genome analysis of non-toxigenic non-O1 versus toxigenic O1 Vibrio cholerae

    PubMed Central

    Mukherjee, Munmun; Kakarla, Prathusha; Kumar, Sanath; Gonzalez, Esmeralda; Floyd, Jared T.; Inupakutika, Madhuri; Devireddy, Amith Reddy; Tirrell, Selena R.; Bruns, Merissa; He, Guixin; Lindquist, Ingrid E.; Sundararajan, Anitha; Schilkey, Faye D.; Mudge, Joann; Varela, Manuel F.

    2015-01-01

    Pathogenic strains of Vibrio cholerae are responsible for endemic and pandemic outbreaks of the disease cholera. The complete toxigenic mechanisms underlying virulence in Vibrio strains are poorly understood. The hypothesis of this work was that virulent versus non-virulent strains of V. cholerae harbor distinctive genomic elements that encode virulence. The purpose of this study was to elucidate genomic differences between the O1 serotypes and non-O1 V. cholerae PS15, a non-toxigenic strain, in order to identify novel genes potentially responsible for virulence. In this study, we compared the whole genome of the non-O1 PS15 strain to the whole genomes of toxigenic serotypes at the phylogenetic level, and found that the PS15 genome was distantly related to those of toxigenic V. cholerae. Thus we focused on a detailed gene comparison between PS15 and the distantly related O1 V. cholerae N16961. Based on sequence alignment we tentatively assigned chromosome numbers 1 and 2 to elements within the genome of non-O1 V. cholerae PS15. Further, we found that PS15 and O1 V. cholerae N16961 shared 98% identity and 766 genes, but of the genes present in N16961 that were missing in the non-O1 V. cholerae PS15 genome, 56 were predicted to encode not only for virulence–related genes (colonization, antimicrobial resistance, and regulation of persister cells) but also genes involved in the metabolic biosynthesis of lipids, nucleosides and sulfur compounds. Additionally, we found 113 genes unique to PS15 that were predicted to encode other properties related to virulence, disease, defense, membrane transport, and DNA metabolism. Here, we identified distinctive and novel genomic elements between O1 and non-O1 V. cholerae genomes as potential virulence factors and, thus, targets for future therapeutics. Modulation of such novel targets may eventually enhance eradication efforts of endemic and pandemic disease cholera in afflicted nations. PMID:25722857

  11. Use of a DNA Microarray for Detection and Identification of Bacterial Pathogens Associated with Fishery Products?

    PubMed Central

    Cao, Boyang; Li, Rongrong; Xiong, Songjin; Yao, Fangfang; Liu, Xiangqian; Wang, Min; Feng, Lu; Wang, Lei

    2011-01-01

    We established a microarray for the simultaneous detection and identification of diverse putative pathogens often associated with fishery products by targeting specific genes of Listeria monocytogenes, Salmonella, Shigella, Staphylococcus aureus, Streptococcus pyogenes, Vibrio cholerae, Vibrio parahaemolyticus, Vibrio vulnificus, and Yersinia enterocolitica and the 16S-23S rRNA gene internal transcribed spacer (ITS) region of Proteus mirabilis and Proteus vulgaris. The microarray contained 26 specific probes and was tested against a total of 123 target bacterial strains that included 55 representative strains, 68 clinical isolates, and 45 strains of other bacterial species that belonged to 8 genera and 34 species, and it was shown to be specific and reproducible. A detection sensitivity of 10 ng DNA or 10 CFU/ml for pure cultures of each target organism demonstrated that the assay was highly sensitive and reproducible. Mock and real fishery product samples were tested by the microarray, and the accuracy was 100%. The DNA microarray method described in this communication is specific, sensitive, and reliable and has several advantages over traditional methods of bacterial culture and antiserum agglutination assays. PMID:21965411

  12. Mechanisms of bacterial pathogenicity

    PubMed Central

    Wilson, J; Schurr, M; LeBlanc, C; Ramamurthy, R; Buchanan, K; Nickerson, C

    2002-01-01

    Pathogenic bacteria utilise a number of mechanisms to cause disease in human hosts. Bacterial pathogens express a wide range of molecules that bind host cell targets to facilitate a variety of different host responses. The molecular strategies used by bacteria to interact with the host can be unique to specific pathogens or conserved across several different species. A key to fighting bacterial disease is the identification and characterisation of all these different strategies. The availability of complete genome sequences for several bacterial pathogens coupled with bioinformatics will lead to significant advances toward this goal. PMID:11930024

  13. Endobiotic bacteria and their pathogenic potential in cnidarian tentacles

    NASA Astrophysics Data System (ADS)

    Schuett, Christian; Doepke, Hilke

    2010-09-01

    Endobiotic bacteria colonize the tentacles of cnidaria. This paper provides first insight into the bacterial spectrum and its potential of pathogenic activities inside four cnidarian species. Sample material originating from Scottish waters comprises the jellyfish species Cyanea capillata and C. lamarckii, hydrozoa Tubularia indivisa and sea anemone Sagartia elegans. Mixed cultures of endobiotic bacteria, pure cultures selected on basis of haemolysis, but also lyophilized samples were prepared from tentacles and used for DGGE-profiling with subsequent phylogenetic analysis of 16S rDNA fragments. Bacteria were detected in each of the cnidarian species tested. Twenty-one bacterial species including four groups of closely related organisms were found in culture material. The species within these groups could not be differentiated from each other (one group of Pseudoalteromonas spp., two groups of Shewanella spp., one group of Vibrio spp.). Each of the hosts exhibits a specific endobacterial spectrum. Solely Cyanea lamarckii harboured Moritella viscosa. Only in Cyanea capillata, members of the Shewanella group #2 and the species Pseudoalteromonas arctica, Shewanella violacea, Sulfitobacter pontiacus and Arcobacter butzleri were detected. Hydrozoa Tubularia indivisa provided an amazingly wide spectrum of nine bacterial species. Exclusively, in the sea anemone Sagartia elegans, the bacterial species P. aliena was found. Overall eleven bacterial species detected were described recently as novel species. Four 16S rDNA fragments generated from lyophilized material displayed extremely low relationship to their next neighbours. These organisms are regarded as members of the endobiotic “terra incognita”. Since the origin of cnidarian toxins is unclear, the possible pathogenic activity of endobiotic bacteria has to be taken into account. Literature data show that their next neighbours display an interesting diversity of haemolytic, septicaemic and necrotic actions including the production of cytotoxins, tetrodotoxin and R-toxin. Findings of haemolysis tests support the literature data. The potential producers are Endozoicimonas elysicola, Moritella viscosa, Photobacterium profundum, P. aliena, P. tetraodonis, Shewanella waksmanii, Vibrio splendidus, V. aestuarius, Arcobacter butzleri.

  14. Lipopolysaccharides isolated from Aeromonas salmonicida and Vibrio anguillarum show quantitative but not qualitative differences in inflammatory outcome in Sparus aurata (Gilthead seabream).

    PubMed

    Boltaña, S; Tridico, R; Teles, M; Mackenzie, S; Tort, L

    2014-08-01

    In fish, the defence system recognises pathogenic microorganisms via pathogen recognition receptors (PRRs) that sense particular structures of the pathogens; the so-called pathogen associated molecular patterns (PAMPs) such as bacterial lipopolysaccharides (LPSs). The result of the PAMP-PRR interactions leads to complex and orchestrated immune responses. In this study, Sparus aurata (Gilthead seabream) were intraperitoneally injected with purified lipopolysaccharide (LPS) from Aeromonas salmonicida (As)- and Vibrio anguillarum (Va) (1 mg*Kgfish(-1)), both Gram negative bacteria responsible for vibriosis and furunculosis respectively, therefore causing an impact upon marine fish cultures. Head-kidney, intestine, spleen, liver and blood samples were collected at 3, 6, 12 and 24 h post-injection. Plasma levels of cortisol, prostaglandins and lactate were measured and were significantly increased after As-LPS and Va-LPS treatment. Furthermore, tissue-specific differences of the gene regulatory patterns were evident for each LPS. When monocyte/macrophage cell cultures were challenged with As-LPS and Va-LPS, the pro-inflammatory cytokine mRNA abundances present a similar pattern of response. However, As-LPS always triggered a stronger response concerning TNF?, IL1? and cyclooxygenase-2 (COX2) mRNA abundance as well as PGE2 levels in the supernatant. Overall, the results indicate that specific LPSs do not activate different pro-inflammatory responses and that the observed gene expression pattern is tissue and concentration dependent. PMID:24954838

  15. Ecology of Vibrio cholerae non-O1 and Salmonella spp. and role of zooplankton in their seasonal distribution in Fukuyama coastal waters, Japan.

    PubMed Central

    Venkateswaran, K; Takai, T; Navarro, I M; Nakano, H; Hashimoto, H; Siebeling, R J

    1989-01-01

    Seasonal variation of human pathogens such as Vibrio Cholerae non-01 and Salmonella spp. in Fukuyama coastal waters and the role of zooplankton in their distribution were studies for a period of 1 year. Comparison of two established methods, viz., the elevated temperature method and the two-step enrichment method of enumerating V. cholerae, showed that the former is superior in the recoveries of V. cholerae non-01. Isolation of this pathogen on a wider range of salinities (0.4 to 32.5%) revealed that these organisms are apparently an autochthonous component of the aquatic environment. Temperature appears to be the most crucial element in governing the distribution of V. cholerae non-01. Among the 69 isolates serotyped, 22 different serovars were identified, while one isolate failed to react with any of the known Louisiana State University antisera tested. Zooplankton samples did not harbor more V. Cholerae non-01 than the water column did. Better isolation of an allochthonous pathogen, viz., Salmonella spp., was noticed from the water samples when swabs were employed. Of the 251 isolates serotyped, 18 serotypes with three variants of Salmonella spp. were identified. A high amount of nutrients in the water column increased the survival rate of these pathogens in saline waters as evidenced by a higher incidence of various serotypes in polluted Fukuyama port than in clean marine waters. Salmonella spp. association between V. cholerae non-01 of Salmonella spp. with zooplankton could be noticed as influencing their seasonal distribution. PMID:2764569

  16. Isolation of Vibrio alginolyticus and Vibrio splendidus from aquacultured carpet shell clam (Ruditapes decussatus) larvae associated with mass mortalities.

    PubMed

    Gómez-León, J; Villamil, L; Lemos, M L; Novoa, B; Figueras, A

    2005-01-01

    Two episodes of mortality of cultured carpet shell clams (Ruditapes decussatus) associated with bacterial infections were recorded during 2001 and 2002 in a commercial hatchery located in Spain. Vibrio alginolyticus was isolated as the primary organism from moribund clam larvae that were obtained during the two separate events. Vibrio splendidus biovar II, in addition to V. alginolyticus, was isolated as a result of a mixed Vibrio infection from moribund clam larvae obtained from the second mortality event. The larval mortality rates for these events were 62 and 73%, respectively. Mortality was also detected in spat. To our knowledge, this is the fist time that these bacterial species have been associated with larval and juvenile carpet shell clam mortality. The bacterial strains were identified by morphological and biochemical techniques and also by PCR and sequencing of a conserved region of the 16S rRNA gene. In both cases bacteria isolated in pure culture were inoculated into spat of carpet shell clams by intravalvar injection and by immersion. The mortality was attributed to the inoculated strains, since the bacteria were obtained in pure culture from the soft tissues of experimentally infected clams. V. alginolyticus TA15 and V. splendidus biovar II strain TA2 caused similar histological lesions that affected mainly the mantle, the velum, and the connective tissue of infected organisms. The general enzymatic activity of both live cells and extracellular products (ECPs), as evaluated by the API ZYM system, revealed that whole bacterial cells showed greater enzymatic activity than ECPs and that the activity of most enzymes ceased after heat treatment (100 degrees C for 10 min). Both strain TA15 and strain TA2 produced hydroxamate siderophores, although the activity was greater in strain TA15. ECPs from both bacterial species at high concentrations, as well as viable bacteria, caused significant reductions in hemocyte survival after 4 h of incubation, whereas no significant differences in viability were observed during incubation with heat-killed bacteria. PMID:15640176

  17. Non-O1/non-O139 Vibrio cholerae carrying multiple virulence factors and V. cholerae O1 in the Chesapeake Bay, Maryland.

    PubMed

    Ceccarelli, Daniela; Chen, Arlene; Hasan, Nur A; Rashed, Shah M; Huq, Anwar; Colwell, Rita R

    2015-03-01

    Non-O1/non-O139 Vibrio cholerae inhabits estuarine and coastal waters globally, but its clinical significance has not been sufficiently investigated, despite the fact that it has been associated with septicemia and gastroenteritis. The emergence of virulent non-O1/non-O139 V. cholerae is consistent with the recognition of new pathogenic variants worldwide. Oyster, sediment, and water samples were collected during a vibrio surveillance program carried out from 2009 to 2012 in the Chesapeake Bay, Maryland. V. cholerae O1 was detected by a direct fluorescent-antibody (DFA) assay but was not successfully cultured, whereas 395 isolates of non-O1/non-O139 V. cholerae were confirmed by multiplex PCR and serology. Only a few of the non-O1/non-O139 V. cholerae isolates were resistant to ampicillin and/or penicillin. Most of the isolates were sensitive to all antibiotics tested, and 77 to 90% carried the El Tor variant hemolysin gene hlyAET, the actin cross-linking repeats in toxin gene rtxA, the hemagglutinin protease gene hap, and the type 6 secretion system. About 19 to 21% of the isolates carried the neuraminidase-encoding gene nanH and/or the heat-stable toxin (NAG-ST), and only 5% contained a type 3 secretion system. None of the non-O1/non-O139 V. cholerae isolates contained Vibrio pathogenicity island-associated genes. However, ctxA, ace, or zot was present in nine isolates. Fifty-five different genotypes showed up to 12 virulence factors, independent of the source of isolation, and represent the first report of both antibiotic susceptibility and virulence associated with non-O1/non-O139 V. cholerae from the Chesapeake Bay. Since these results confirm the presence of potentially pathogenic non-O1/non-O139 V. cholerae, monitoring for total V. cholerae, regardless of serotype, should be done within the context of public health. PMID:25556194

  18. Production and characterization of a monoclonal antibody against mannose-sensitive hemagglutinin of Vibrio cholerae.

    PubMed

    Falero, G; Rodríguez, B L; Valmaseda, T; Pérez, M E; Pérez, J L; Fando, R; Robert, A; Campos, J; Silva, A; Sierra, G; Benítez, J A

    1998-02-01

    We have generated murine monoclonal antibodies (MAb) against Vibrio cholerae mannose-sensitive hemagglutinin (MSHA) using conventional hybridoma procedures. Seven hybridomas were obtained and one characterized. Hybridoma 2F12/F1 secreted an antibody of the IgG3 type that reacted with a 17-kDa antigen corresponding to the product of the mshA gene. This MAb inhibited mannose-sensitive agglutination of chicken erythrocytes by EL tor and O139 vibrios. Vibrios expressing MSHA activity inhibited binding of the antibody secreted by 2F12/F1 to MSHA-coated microtiter plates. PMID:9523239

  19. Bacillus sp. LT3 improves the survival of gnotobiotic brine shrimp (Artemia franciscana) larvae challenged with Vibrio campbellii by enhancing the innate immune response and by decreasing the activity of shrimp-associated vibrios.

    PubMed

    Niu, Yufeng; Defoirdt, Tom; Baruah, Kartik; Van de Wiele, Tom; Dong, Shuanglin; Bossier, Peter

    2014-10-10

    Bacteria belonging to the genus Bacillus are amongst the most intensively studied group of bacteria for use as probiotics in aquaculture. However, the exact mechanism of action of these bacteria is often not well described, and the microbiota that are naturally present in cultures of test organisms often compromise the interpretation of the results. The present study aimed to evaluate the putative probiotic effect of Bacillus sp. LT3 in a model system with gnotobiotic brine shrimp Artemia franciscana larvae. The strain significantly increased the survival of brine shrimp larvae challenged with Vibrio campbellii when administered 6h before the challenge. Under these conditions, LT3 was able to colonize the brine shrimp gastrointestinal tract and to decrease the in vivo pathogen activity as indicated by the bioluminescence of the V. campbellii associated with brine shrimp larvae. In order to investigate the effect of the Bacillus strain on the innate immune system of the brine shrimp larvae, prophenoloxidase and transglutaminase mRNA levels were monitored, while heat shock protein 70 mRNA levels were measured as an indicator of physiological stress. Interestingly, 12h after challenge, the prophenoloxidase mRNA level in the larvae pre-treated with LT3 and challenged with V. campbellii was approximately 8-fold higher than in the other treatments. Further, a decreased mRNA level of transglutaminase gene and heat shock protein 70 gene suggested that pretreatment with LT3 results in less stress and tissue damage in the brine shrimp larvae upon V. campbellii challenge. These results indicated that Bacillus sp. LT3 could improve the survival of brine shrimp larvae when challenged with pathogenic V. campbellii, both by decreasing the in vivo activity of the pathogen and by priming the innate immune response through activating the prophenoloxidase system. PMID:25190276

  20. Plant pathogenic Pseudomonas species

    Microsoft Academic Search

    Monica Höfte; PAUL DE VOS

    In the current taxonomy, plant pathogenic Pseudomonas species are restricted to rRNA group I organisms belonging to the Gamma subclass of Proteobacteria. Currently, about 21 validly described plant pathogenic Pseudomonas species are known. The most important species is P. syringae with more than 50 described pathovars. The pathovar concept is confusing and the taxonomy of P. syringae needs revision. P.

  1. Emerging foodborne pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The emergence of new foodborne pathogens is due to a number of factors. An important factor is the globalization of the food supply with the possibility of the introduction of foodborne pathogens from other countries. Animal husbandry, food production, food processing, and food distribution system...

  2. Emerging foodborne pathogens

    Microsoft Academic Search

    Robert V. Tauxe

    2002-01-01

    The broad spectrum of foodborne infections has changed dramatically over time, as well-established pathogens have been controlled or eliminated, and new ones have emerged. The burden of foodborne disease remains substantial: one in four Americans is estimated to have a significant foodborne illness each year. The majority of these illnesses are not accounted for by known pathogens, so more must

  3. Radiation resistances and decontamination of common pathogenic bacteria contaminated in white scar oyster ( Crassostrea belcheri) in Thailand

    NASA Astrophysics Data System (ADS)

    Thupila, Nunticha; Ratana-arporn, Pattama; Wilaipun, Pongtep

    2011-07-01

    In Thailand, white scar oyster ( Crassostrea belcheri) was ranked for premium quality, being most expensive and of high demand. This oyster is often eaten raw, hence it may pose health hazards to consumers when contaminated with food-borne pathogens. As limited alternative methods are available to sterilize the oyster while preserving the raw characteristic, irradiation may be considered as an effective method for decontamination. In this study, the radiation resistance of pathogenic bacteria commonly contaminating the oyster and the optimum irradiation doses for sterilization of the most radiation resistant bacteria were investigated. The radiation decimal reduction doses ( D10) of Salmonella Weltevreden DMST 33380, Vibrio parahaemolyticus ATCC 17802 and Vibrio vulnificus DMST 5852 were determined in broth culture and inoculated oyster homogenate. The D10 values of S. Weltevreden, V. parahaemolyticus and V. vulnificus in broth culture were 0.154, 0.132 and 0.059 kGy, while those of inoculated oyster homogenate were 0.330, 0.159 and 0.140 kGy, respectively. It was found that among the pathogens tested, S. Weltevreden was proved to be the most resistant species. An irradiation dose of 1.5 kGy reduced the counts of 10 5 CFU/g S. Weltevreden inoculated in oyster meat to an undetectable level. The present study indicated that a low-dose irradiation can improve the microbial quality of oyster and further reduce the risks from the food-borne pathogens without adversely affecting the sensory attributes.

  4. Simultaneous, specific and real-time detection of biothreat and frequently encountered food-borne pathogens

    PubMed Central

    Woubit, Abdela Salah; Yehualaeshet, Teshome; Habtemariam, Tsegaye; Samuel, Temesgen

    2012-01-01

    The bacterial genera Escherichia, Salmonella, Shigella, Vibrio, Yersinia and Francisella include important food safety and biothreat agents causing food-related and other human illnesses worldwide. We aimed to develop rapid methods with the capability to simultaneously and differentially detect all six pathogens in one run. Our initial experiments to use previously reported sets of primers revealed non-specificity of some of the sequences when tested against a broader array of pathogens, or proved not optimal for simultaneous detection parameters. By extensive mining of the whole genome and protein databases of diverse closely and distantly related bacterial species and strains, we have identified unique genome regions, which we utilized to develop a detection platform. Twelve of the specific genomic targets we have identified to design the primers in F. tularensis ssp. tularensis, F. tularensis ssp. novicida, S. dysentriae, S. typhimurium, V. cholera, Y. pestis, and Y. pseudotuberculosis contained either hypothetical or putative proteins, the functions of which have not been clearly defined. Corresponding primer sets were designed from the target regions for use in real-time PCR assays to detect specific biothreat pathogens at species or strain levels. The primer sets were first tested by in-silico PCR against whole genome sequences of different species, sub-species, or strains and then by in vitro PCR against genomic DNA preparations from 23 strains representing six biothreat agents (E.coli O157:H7 strain EDL 933, Shigella dysentriae, Salmonella typhi, Francisella tularensis ssp. tularensis, Vibrio cholera, and Yersinia pestis) and six foodborne pathogens (Salmonella typhimurium, Salmonella saintpaul, Shigella sonnei, Francisella novicida, Vibrio parahemolytica and Yersinia pseudotuberculosis). Each pathogen was specifically identifiable at the genus and species levels. Sensitivity assays performed using purified DNA showed the lowest detection limit of 640 fg DNA/µl for F. tularensis. A preliminary test done to detect Shigella organisms in a milk matrix showed that 6–60 colony forming units of the bacterium per milliliter of milk could be detected in about an hour. Therefore, we have developed a platform to simultaneously detect foodborne pathogen and biothreat agents specifically and in real-time. Such a platform could enable rapid detection or confirmation of contamination by these agents. PMID:22488053

  5. Pathogen inactivation techniques.

    PubMed

    Pelletier, J P R; Transue, S; Snyder, E L

    2006-01-01

    The desire to rid the blood supply of pathogens of all types has led to the development of many technologies aimed at the same goal--eradication of the pathogen(s) without harming the blood cells or generating toxic chemical agents. This is a very ambitious goal, and one that has yet to be achieved. One approach is to shun the 'one size fits all' concept and to target pathogen-reduction agents at the Individual component types. This permits the development of technologies that might be compatible with, for example, plasma products but that would be cytocidal and thus incompatible with platelet concentrates or red blood cell units. The technologies to be discussed include solvent detergent and methylene blue treatments--designed to inactivate plasma components and derivatives; psoralens (S-59--amotosalen) designed to pathogen-reduce units of platelets; and two products aimed at red blood cells, S-303 (a Frale--frangible anchor-linker effector compound) and Inactine (a binary ethyleneimine). A final pathogen-reduction material that might actually allow one material to inactivate all three blood components--riboflavin (vitamin B2)--is also under development. The sites of action of the amotosalen (S-59), the S-303 Frale, Inactine, and riboflavin are all localized in the nucleic acid part of the pathogen. Solvent detergent materials act by dissolving the plasma envelope, thus compromising the integrity of the pathogen membrane and rendering it non-infectious. By disrupting the pathogen's ability to replicate or survive, its infectivity is removed. The degree to which bacteria and viruses are affected by a particular pathogen-reducing technology relates to its Gram-positive or Gram-negative status, to the sporulation characteristics for bacteria, and the presence of lipid or protein envelopes for viruses. Concerns related to photoproducts and other breakdown products of these technologies remain, and the toxicology of pathogen-reduction treatments is a major ongoing area of investigation. Clearly, regulatory agencies have a major role to play in the evaluation of these new technologies. This chapter will cover the several types of pathogen-reduction systems, mechanisms of action, the inactivation efficacy for specific types of pathogens, toxicology of the various systems and the published research and clinical trial data supporting their potential usefulness. Due to the nature of the field, pathogen reduction is a work in progress and this review should be considered as a snapshot in time rather than a clear picture of what the future will bring. PMID:16377551

  6. Processes for managing pathogens.

    PubMed

    Godfree, Alan; Farrell, Joseph

    2005-01-01

    Wastewater contains human, animal, and plant pathogens capable of causing viral, bacterial, or parasitic infections. There are several routes whereby sewage pathogens may affect human health, including direct contact, contamination of food crops, zoonoses, and vectors. The range and numbers of pathogens in municipal wastewater vary with the level of endemic disease in the community, discharges from commercial activities, and seasonal factors. Regulations to control pathogen risk in the United States and Europe arising from land application of biosolids are based on the concept of multiple barriers to the prevention of transmission. The barriers are (i) treatment to reduce pathogen content and vector attraction, (ii) restrictions on crops grown on land to which biosolids have been applied, and (iii) minimum intervals following application and grazing or harvesting. Wastewater treatment reduces number of pathogens in the wastewater by concentrating them with the solids in the sludge. Although some treatment processes are designed specifically to inactivate pathogens, many are not, and the actual mechanisms of microbial inactivation are not fully understood for all processes. Vector attraction is reduced by stabilization (reduction of readily biodegradable material) and/or incorporation immediately following application. Concerns about health risks have renewed interest in the effects of treatment (on pathogens) and advanced treatment methods, and work performed in the United States suggests that Class A pathogen reduction can be achieved less expensively than previously thought. Effective pathogen risk management requires control to the complete chain of sludge treatment, biosolids handling and application, and post-application activities. This may be achieved by adherence to quality management systems based on hazard analysis critical control point (HACCP) principles. PMID:15647539

  7. Characterization of the Vibrio cholerae extracellular matrix: a top-down solid-state NMR approach.

    PubMed

    Reichhardt, Courtney; Fong, Jiunn C N; Yildiz, Fitnat; Cegelski, Lynette

    2015-01-01

    Bacterial biofilms are communities of bacterial cells surrounded by a self-secreted extracellular matrix. Biofilm formation by Vibrio cholerae, the human pathogen responsible for cholera, contributes to its environmental survival and infectivity. Important genetic and molecular requirements have been identified for V. cholerae biofilm formation, yet a compositional accounting of these parts in the intact biofilm or extracellular matrix has not been described. As insoluble and non-crystalline assemblies, determinations of biofilm composition pose a challenge to conventional biochemical and biophysical analyses. The V. cholerae extracellular matrix composition is particularly complex with several proteins, complex polysaccharides, and other biomolecules having been identified as matrix parts. We developed a new top-down solid-state NMR approach to spectroscopically assign and quantify the carbon pools of the intact V. cholerae extracellular matrix using ¹³C CPMAS and ¹³C{(¹?N}, ¹?N{³¹P}, and ¹³C{³¹P}REDOR. General sugar, lipid, and amino acid pools were first profiled and then further annotated and quantified as specific carbon types, including carbonyls, amides, glycyl carbons, and anomerics. In addition, ¹?N profiling revealed a large amine pool relative to amide contributions, reflecting the prevalence of molecular modifications with free amine groups. Our top-down approach could be implemented immediately to examine the extracellular matrix from mutant strains that might alter polysaccharide production or lipid release beyond the cell surface; or to monitor changes that may accompany environmental variations and stressors such as altered nutrient composition, oxidative stress or antibiotics. More generally, our analysis has demonstrated that solid-state NMR is a valuable tool to characterize complex biofilm systems. PMID:24911407

  8. Quorum Sensing Determines the Choice of Antiphage Defense Strategy in Vibrio anguillarum

    PubMed Central

    Tan, Demeng; Svenningsen, Sine Lo

    2015-01-01

    ABSTRACT Selection for phage resistance is a key driver of bacterial diversity and evolution, and phage-host interactions may therefore have strong influence on the genetic and functional dynamics of bacterial communities. In this study, we found that an important, but so far largely overlooked, determinant of the outcome of phage-bacterial encounters in the fish pathogen Vibrio anguillarum is bacterial cell-cell communication, known as quorum sensing. Specifically, V. anguillarum PF430-3 cells locked in the low-cell-density state (?vanT mutant) express high levels of the phage receptor OmpK, resulting in a high susceptibility to phage KVP40, but achieve protection from infection by enhanced biofilm formation. By contrast, cells locked in the high-cell-density state (?van? mutant) are almost completely unsusceptible due to quorum-sensing-mediated downregulation of OmpK expression. The phenotypes of the two quorum-sensing mutant strains are accurately reflected in the behavior of wild-type V. anguillarum, which (i) displays increased OmpK expression in aggregated cells compared to free-living variants in the same culture, (ii) displays a clear inverse correlation between ompK mRNA levels and the concentration of N-acylhomoserine lactone quorum-sensing signals in the culture medium, and (iii) survives mainly by one of these two defense mechanisms, rather than by genetic mutation to phage resistance. Taken together, our results demonstrate that V. anguillarum employs quorum-sensing information to choose between two complementary antiphage defense strategies. Further, the prevalence of nonmutational defense mechanisms in strain PF430-3 suggests highly flexible adaptations to KVP40 phage infection pressure, possibly allowing the long-term coexistence of phage and host. PMID:26081633

  9. Expression of glutamine synthetase in Tegillarca granosa (Bivalvia, Arcidae) hemocytes stimulated by Vibrio parahaemolyticus and lipopolysaccharides.

    PubMed

    Bao, Y B; Li, L; Ye, M X; Dong, Y H; Jin, W X; Lin, Z H

    2013-01-01

    The blood cockle, Tegillarca granosa, is a widely consumed clam in the Indo-Pacific region. Glutamine synthetase (GS) is an enzyme that plays an essential role in the metabolism of nitrogen by catalyzing the condensation of glutamate and ammonia to form glutamine. We identified the GS of T. granosa (Tg-GS) from hemocytes by 3'- and 5'-rapid amplification of cDNA ends (RACE)-PCR. The full-length cDNA consisted of 1762 bp, with a 1104-bp open reading frame encoding 367 amino acids. Sequence comparison showed that Tg-GS has homology to GS of other organisms, with 79.78% identity with GS from the Pacific oyster Crassostrea gigas, 71.98% identity with GS from the zebrafish Danio rerio, and 68.96% identity with human Homo sapiens GS. A C-beta-Grasp domain and an N-catalytic domain were identified in Tg-GS, indicating that Tg-GS should be classified as a new member of the GS family. A quantitative RT-PCR assay was used to detect mRNA expression of Tg-GS in five different tissues. Higher levels of mRNA expression of GS were detected in the tissues of hemocytes and the mantle. Up-regulation of GS by challenge with the bacteria Vibrio parahaemolyticus and with bacterial wall lipopolysaccharides showed that GS plays a role in anti-bacterial immunity. We conclude that pathogen infection significantly induces expression level of Tg- GS, and that activation of GS influences the immune response of T. granosa by increasing glutamine concentration. PMID:23661439

  10. Host-Nonspecific Iron Acquisition Systems and Virulence in the Zoonotic Serovar of Vibrio vulnificus

    PubMed Central

    Pajuelo, David; Lee, Chung-Te; Roig, Francisco J.; Lemos, Manuel L.; Hor, Lien-I

    2014-01-01

    The zoonotic serovar of Vibrio vulnificus (known as biotype 2 serovar E) is the etiological agent of human and fish vibriosis. The aim of the present work was to discover the role of the vulnibactin- and hemin-dependent iron acquisition systems in the pathogenicity of this zoonotic serovar under the hypothesis that both are host-nonspecific virulence factors. To this end, we selected three genes for three outer membrane receptors (vuuA, a receptor for ferric vulnibactin, and hupA and hutR, two hemin receptors), obtained single and multiple mutants as well as complemented strains, and tested them in a series of in vitro and in vivo assays, using eels and mice as animal models. The overall results confirm that hupA and vuuA, but not hutR, are host-nonspecific virulence genes and suggest that a third undescribed host-specific plasmid-encoded system could also be used by the zoonotic serovar in fish. hupA and vuuA were expressed in the internal organs of the animals in the first 24 h of infection, suggesting that they may be needed to achieve the population size required to trigger fatal septicemia. vuuA and hupA were sequenced in strains representative of the genetic diversity of this species, and their phylogenies were reconstructed by multilocus sequence analysis of selected housekeeping and virulence genes as a reference. Given the overall results, we suggest that both genes might form part of the core genes essential not only for disease development but also for the survival of this species in its natural reservoir, the aquatic environment. PMID:24478087

  11. Calcium and Iron Regulate Swarming and Type III Secretion in Vibrio parahaemolyticus? †

    PubMed Central

    Gode-Potratz, Cindy J.; Chodur, Daniel M.; McCarter, Linda L.

    2010-01-01

    Here, we probe the response to calcium during growth on a surface and show that calcium influences the transcriptome and stimulates motility and virulence of Vibrio parahaemolyticus. Swarming (but not swimming) gene expression and motility were enhanced by calcium. Calcium also elevated transcription of one of the organism's two type III secretion systems (T3SS1 but not T3SS2) and heightened cytotoxicity toward host cells in coculture. Calcium stimulation of T3SS gene expression has not been reported before, although low calcium is an inducing signal for the T3SS of many organisms. EGTA was also found to increase T3SS1 gene expression and virulence; however, this was demonstrated to be the consequence of iron rather than calcium chelation. Ectopic expression of exsA, encoding the T3SS1 AraC-type regulator, was used to define the extent of the T3SS1 regulon and verify its coincident induction by calcium and EGTA. To begin to understand the regulatory mechanisms modulating the calcium response, a calcium-repressed, LysR-type transcription factor named CalR was identified and shown to repress swarming and T3SS1 gene expression. Swarming and T3SS1 gene expression were also demonstrated to be linked by LafK, a ?54-dependent regulator of swarming, and additionally connected by a negative-feedback loop on the swarming regulon propagated by ExsA. Thus, calcium and iron, two ions pertinent for a marine organism and pathogen, play a signaling role with global consequences on the regulation of gene sets that are relevant for surface colonization and infection. PMID:20851895

  12. A thermostabilized magnetogenosensing assay for DNA sequence-specific detection and quantification of Vibrio cholerae.

    PubMed

    Low, Kim-Fatt; Karimah, Abdah; Yean, Chan Yean

    2013-09-15

    Vibrio cholerae is a human pathogen that causes mild to severe diarrheal illnesses and has major public health significance. Herein, we present a thermostabilized electrochemical genosensing assay combining the use of magnetic beads as a biorecognition platform and gold nanoparticles as a hybridization tag for the detection and quantification of V. cholerae lolB gene single-stranded asymmetric PCR amplicons as an alternative to the time-consuming classical isolation method. This thermostabilized, pre-mixed, pre-aliquoted and ready-to-use magnetogenosensing assay simplified the procedures and permitted the reaction to be conducted at room temperature. The asymmetric PCR amplicons were hybridized to a magnetic bead-functionalized capture probe and a fluorescein-labeled detection probe followed by tagging with gold nanoparticles. Electrochemical detection of the chemically dissolved gold nanoparticles was performed using the differential pulse anodic stripping voltammetry method. The real-time stability evaluation of thermostabilized assay was found to be stable for at least 180 days at room temperature (25-30°C). The analytical specificity of the assay was 100%, while its analytical sensitivity was linearly related to different concentrations of 200-mer synthetic target, purified genomic DNA, and bacterial culture with a limit of detection (LoD) of 3.9nM, 5pg/µl, and 10(3)CFU/ml, respectively. The clinical applicability of the assay was successfully validated using spiked stool samples with an average current signal-to-cut-off ratio of 10.8. Overall, the precision of the assay via relative standard deviation was <10%, demonstrating its reliability and accuracy. PMID:23545172

  13. Widespread epidemic cholera caused by a restricted subset of Vibrio cholerae clones.

    PubMed

    Moore, S; Thomson, N; Mutreja, A; Piarroux, R

    2014-05-01

    Since 1817, seven cholera pandemics have plagued humankind. As the causative agent, Vibrio cholerae, is autochthonous in the aquatic ecosystem and some studies have revealed links between outbreaks and fluctuations in climatic and aquatic conditions, it has been widely assumed that cholera epidemics are triggered by environmental factors that promote the growth of local bacterial reservoirs. However, mounting epidemiological findings and genome sequence analysis of clinical isolates have indicated that epidemics are largely unassociated with most of the V. cholerae strains in aquatic ecosystems. Instead, only a specific subset of V. cholerae El Tor 'types' appears to be responsible for current epidemics. A recent report examining the evolution of a variety of V. cholerae strains indicates that the current pandemic is monophyletic and originated from a single ancestral clone that has spread globally in successive waves. In this review, we examine the clonal nature of the disease, with the example of the recent history of cholera in the Americas. Epidemiological data and genome sequence-based analysis of V. cholerae isolates demonstrate that the cholera epidemics of the 1990s in South America were triggered by the importation of a pathogenic V. cholerae strain that gradually spread throughout the region until local outbreaks ceased in 2001. Latin America remained almost unaffected by the disease until a new toxigenic V. cholerae clone was imported into Haiti in 2010. Overall, cholera appears to be largely caused by a subset of specific V. cholerae clones rather than by the vast diversity of V. cholerae strains in the environment. PMID:24575898

  14. Biochemical, Serological, and Virulence Characterization of Clinical and Oyster Vibrio parahaemolyticus Isolates

    PubMed Central

    Lüdeke, Catharina H. M.; Bowers, John C.; Garrett, Nancy; Fischer, Markus; Parsons, Michele B.; Bopp, Cheryl A.; DePaola, Angelo

    2012-01-01

    In this study, 77 clinical and 67 oyster Vibrio parahaemolyticus isolates from North America were examined for biochemical profiles, serotype, and the presence of potential virulence factors (tdh, trh, and type III secretion system [T3SS] genes). All isolates were positive for oxidase, indole, and glucose fermentation, consistent with previous reports. The isolates represented 35 different serotypes, 9 of which were shared by clinical and oyster isolates. Serotypes associated with pandemic strains (O1:KUT, O1:K25, O3:K6, and O4:K68) were observed for clinical isolates, and 7 (9%) oyster isolates belonged to serotype O1:KUT. Of the clinical isolates, 27% were negative for tdh and trh, while 45% contained both genes. Oyster isolates were preferentially selected for the presence of tdh and/or trh; 34% contained both genes, 42% had trh but not tdh, and 3% had tdh but not trh. All but 1 isolate (143/144) had at least three of the four T3SS1 genes examined. The isolates lacking both tdh and trh contained no T3SS2? or T3SS2? genes. All clinical isolates positive for tdh and negative for trh possessed all T3SS2? genes, and all isolates negative for tdh and positive for trh possessed all T3SS2? genes. The two oyster isolates containing tdh but not trh possessed all but the vopB2 gene of T3SS2?, as reported previously. In contrast to the findings of previous studies, all strains examined that were positive for both tdh and trh also carried T3SS2? genes. This report identifies the serotype as the most distinguishing feature between clinical and oyster isolates. Our findings raise concerns about the reliability of the tdh, trh, and T3SS genes as virulence markers and highlight the need for more-detailed pathogenicity investigations of V. parahaemolyticus. PMID:22535979

  15. Chemical communication in the gut: Effects of microbiota-generated metabolites on gastrointestinal bacterial pathogens.

    PubMed

    Vogt, Stefanie L; Peña-Díaz, Jorge; Finlay, B Brett

    2015-08-01

    Gastrointestinal pathogens must overcome many obstacles in order to successfully colonize a host, not the least of which is the presence of the gut microbiota, the trillions of commensal microorganisms inhabiting mammals' digestive tracts, and their products. It is well established that a healthy gut microbiota provides its host with protection from numerous pathogens, including Salmonella species, Clostridium difficile, diarrheagenic Escherichia coli, and Vibrio cholerae. Conversely, pathogenic bacteria have evolved mechanisms to establish an infection and thrive in the face of fierce competition from the microbiota for space and nutrients. Here, we review the evidence that gut microbiota-generated metabolites play a key role in determining the outcome of infection by bacterial pathogens. By consuming and transforming dietary and host-produced metabolites, as well as secreting primary and secondary metabolites of their own, the microbiota define the chemical environment of the gut and often determine specific host responses. Although most gut microbiota-produced metabolites are currently uncharacterized, several well-studied molecules made or modified by the microbiota are known to affect the growth and virulence of pathogens, including short-chain fatty acids, succinate, mucin O-glycans, molecular hydrogen, secondary bile acids, and the AI-2 quorum sensing autoinducer. We also discuss challenges and possible approaches to further study of the chemical interplay between microbiota and gastrointestinal pathogens. PMID:25958185

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

    PubMed

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

    2014-12-01

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

  17. Drug-sensitivity of El Tor vibrio strains isolated in the Philippines in 1964 and 1965*

    PubMed Central

    Kuwahara, Shogo; Goto, Sachiko; Kimura, Masatake; Abe, Hisao

    1967-01-01

    About 1500 strains of El Tor vibrios, isolated in 1964 and 1965 in the Philippines, were examined for their susceptibilities to 17 drugs. All the strains tested were highly sensitive to dihydroxymethyl-furalazine, and most were highly sensitive to tetracycline hydrochloride, chloramphenicol and erythromycin, and moderately sensitive to novobiocin, dihydrostreptomycin sulfate, kanamycin and neomycin. They showed a remarkable fluctuation of sensitivity to ampicillin, cefaloridine, cefalotin and sulfafurazole, and a high resistance to benzylpenicillin sodium, oleandomycin and spiramycin. Experimental confirmation was provided of the fact that El Tor vibrios and non-agglutinable vibrios can be distinguished from classical cholera vibrios by their resistance to polymyxin B and colistin. Highly streptomycin-resistant strains, and to a lesser extent ampicillin- and sulfafurazole-resistant strains, were relatively often isolated from cholera patients who had been treated with antibiotics. One patient yielded a strain resistant to tetracycline, chloramphenicol, streptomycin and sulfafurazole. PMID:4870079

  18. H-NOXmediated nitric oxide sensing modulates symbiotic colonization by Vibrio fischeri

    E-print Network

    McFall-Ngai, Margaret

    H-NOX­mediated nitric oxide sensing modulates symbiotic colonization by Vibrio fischeri Yanling | colonization Small molecules have important signaling functions in microbe­ microbe and microbe in the mutualistic symbiotic asso- ciationbetweentheHawa

  19. Constitutive Type VI Secretion System Expression Gives Vibrio cholerae Intra- and Interspecific Competitive Advantages

    E-print Network

    Unterweger, Daniel

    The type VI secretion system (T6SS) mediates protein translocation across the cell membrane of Gram-negative bacteria, including Vibrio cholerae – the causative agent of cholera. All V. cholerae strains examined to date ...

  20. The Association of Virulent Vibrio Spp. Bacteria on Gafftopsail and Hardhead Catfish in Galveston Bay 

    E-print Network

    Gilbert, Leslie Deanne

    2011-10-21

    Vibrio vulnificus (Vv) and V. parahaemolyticus (Vp) are gram negative, halophilic bacteria that occur naturally in estuarine waters of Galveston Bay. Both bacteria have the potential to cause infections in humans either ...

  1. Lysozyme gene expression by hemocytes of Pacific white shrimp, Litopenaeus vannamei, after injection with Vibrio

    E-print Network

    Burnett, Louis E.

    Lysozyme gene expression by hemocytes of Pacific white shrimp, Litopenaeus vannamei, after antibacterial protein produced by shrimp hemocytes, within tissues of Litopenaeus vannamei Boone in response rights reserved. Keywords: Litopenaeus vannamei; Shrimp; Hemocyte; Vibrio; Lysozyme; Gene expression

  2. RESPONSES OF OYSTER (CRASSOSTREA VIRGINICA) HEMOCYTES TO NONPATHOGENIC AND CLINICAL ISOLATES OF VIBRIO PARAHAEMOLYTICUS

    EPA Science Inventory

    Bacterial uptake by oysters (Crassostrea virginica) and bactericidal activity of oyster hemocytes were studied using four environmental isolates and three clinical isolates of Vibrio parahaemolyticus. Clinical isolates (2030, 2062, 2107) were obtained from gastroenteritis patien...

  3. DIFFERENTIAL EFFECTS OF OYSTER (CRASSOSTREA VIRGINICA) DEFENSES ON CLINICAL AND ENVIRONMENTAL ISOLATES OF VIBRIO PARAHEMOLYTICUS

    EPA Science Inventory

    Three clinical (2030, 2062, and 2107) and three environmental (1094, 1163, and ATCC 17802) isolates of Vibrio parahaemolyticus were exposed to hemocytes and plasma collected from oysters (Crassostrea virginica) to determine their susceptibility to putative oyster defenses. Clinic...

  4. INFLUENCE OF SEASONAL FACTORS ON OYSTER HEMOCYTE KILLING OF VIBRIO PARAHEMOLYTICUS

    EPA Science Inventory

    Seasonal variation of cellular defenses of oyster Crassostrea virginica against Vibrio parahaemolyticus were examined from June 1997 to December 1998 using a recently developed bactericidal assay that utilizes a tetrazolium dye. Mean hemocyte numbers, plasma lysozyme, and P. mari...

  5. Signaling During Pathogen Infection

    NSDL National Science Digital Library

    Sylvia Munter (University of Heidelberg Medical School; Department of Parasitology REV)

    2006-05-16

    Pathogens infect almost every living organism. In animals, including humans, the diversity of pathogens ranges from viruses, bacteria, and unicellular parasites to complex fungi, worms, and arthropods. Because pathogens have coevolved with their hosts and have sometimes been coopted as symbionts or commensals, each pathogen/host pair represents a striking success story of survival that reflects the biological complexity of both parties. All invading microorganisms face similar problems, such as gaining access to their host, achieving successful replication, and spreading to a similar or different host. It is therefore not surprising that many different pathogens target similar organs, cell types, and even molecules to achieve their goals. However, no two microbial parasites appear to be completely alike. Although they often target similar signaling networks, they do so in subtly different ways to achieve the desired outcome. This review has eight figures, three movies, and 139 citations and emphasizes two well-established signaling pathways that are often activated during the interaction of different pathogens with their host cells. It illustrates a small part of how the dissection of host/pathogen interactions can reveal, on a molecular scale, a nature shaped by evolutionary forces that can rival the great descriptions of our macroscopic world.

  6. Peptide nucleic acid fluorescence in-situ hybridization for identification of Vibrio spp. in aquatic products and environments.

    PubMed

    Zhang, Xiaofeng; Li, Ke; Wu, Shan; Shuai, Jiangbing; Fang, Weihuan

    2015-08-01

    A peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) method was developed for specific detection of the Vibrio genus. In silico analysis by BLAST and ProbeCheck showed that the designed PNA probe targeting the 16S rRNAs was suitable for specific identification of Vibrio. Specificity and sensitivity of the probe Vib-16S-1 were experimentally verified by its reactivity against 18 strains of 9 Vibrio species and 14 non-Vibrio strains of 14 representative species. The PNA-FISH assay was able to identify 47 Vibrio positive samples from selectively enriched cultures of 510 samples of aquatic products and environments, comparable with the results obtained by biochemical identification and real-time PCR. We conclude that PNA-FISH can be an alternative method for rapid identification of Vibrio species in a broad spectrum of seafood or related samples. PMID:25955286

  7. Random Amplified Polymorphic Dna-PCR Typing of Vibrio parahaemolyticus Isolated from Local Cockles (Anadara granosa)

    Microsoft Academic Search

    Lesley Maurice Bilung; Son Radu; Abdul Rani Bahaman; Raha Abdul Rahim; Suhaimi Napis; Cheah Yoke Kqueen; Chandrika Murugaiah; Yousr Abdul Hadi; Tunung Robin; Mitsuaki Nishibuchi

    2005-01-01

    Randomly amplified polymorphic DNA (RAPD) was used in this study to examine the genetic relatedness among the Vibrio parahaemolyticus strains. In the analysis by RAPD-PCR, the size for RAPD fragments ranged from 0.25 to 10.0 kb with average number of ten bands. The RAPD profiles revealed a high level of DNA sequence diversity within the Vibrio parahaemolyticus strains tested. Hence,

  8. Dominant Bacterial Genera of a Tilapia Fish Farm and RAPD Typing of Vibrio Isolates

    Microsoft Academic Search

    Shuxia Lu; Robert E. Levin

    2008-01-01

    The predominant bacterial genera present in the fish tank water of a sustainable tilapia fish farm system were found to be Vibrio (39.7-69%), Aeromonas (16-21.6%), Pseudomanas (1.8-2.0%), and Shewanella (4.0-9.9%). Each of the 69 Vibrio isolates obtained on March 5, 2003 from tilapia fish tank water was subjected to RAPD-PCR analysis separately with three decamer primers PB1, PB4 and HLWL74.

  9. The Association of Virulent Vibrio Spp. Bacteria on Gafftopsail and Hardhead Catfish in Galveston Bay

    E-print Network

    Gilbert, Leslie Deanne

    2011-10-21

    THE ASSOCIATION OF VIRULENT VIBRIO SPP. BACTERIA ON GAFFTOPSAIL AND HARDHEAD CATFISH IN GALVESTON BAY A Thesis by LESLIE DEANNE GILBERT Submitted to the Office of Graduate Studies of Texas A&M University in partial... Catfish in Galveston Bay Copyright 2010 Leslie Deanne Gilbert THE ASSOCIATION OF VIRULENT VIBRIO SPP. BACTERIA ON GAFFTOPSAIL AND HARDHEAD CATFISH IN GALVESTON BAY A Thesis by LESLIE DEANNE GILBERT Submitted to the Office of Graduate...

  10. MiR-31 modulates coelomocytes ROS production via targeting p105 in Vibrio splendidus challenged sea cucumber Apostichopus japonicus in vitro and in vivo.

    PubMed

    Lu, Meng; Zhang, Pengjuan; Li, Chenghua; Zhang, Weiwei; Jin, Chunhua; Han, Qingxi

    2015-08-01

    MiR-31 is a critical regulator of gene expression in many pathogenic processes in vertebrates. In this study, we identified p105 as a novel target of miR-31 in Apostichopus japonicus and investigated their regulatory roles in vitro and in vivo. The negative expression profiles between miR-31 and Ajp105 were detected in both LPS-exposed primary coelomocytes and Vibrio splendidus-challenged sea cucumber. Co-infection miR-31 mimics significantly depressed the expression of Ajp105 and increased ROS production in vitro. In contrast, miR-31 inhibitor significantly elevated the expression of Ajp105 and decreased ROS level. Consistently, miR-31 over-expression or Ajp105 silencing in vivo both greatly promoted ROS accumulation. Taken together, our findings confirmed that miR-31 could modulate respiratory burst via targeting Ajp105 during sea cucumber pathological development. PMID:25917973

  11. Molecular characteristic and expression analysis of collagenolytic serine protease from the Chinese mitten crab Eriocheir sinensis with defense response to Vibrio anguillarum challenge.

    PubMed

    Yang, Q Z; Yang, Z J; Zhang, Y; Li, X L; Zhang, W

    2014-01-01

    A novel collagenolytic serine protease (CLSP) was cloned from the hemocytes of the Chinese mitten crab Eriocheir sinensis (Es-CLSP). The full-length cDNA of Es-CLSP contains 990 nucleotides. It encodes a 270-amino acid-long peptide with the mature peptide containing 221 amino acids. It contains the conserved catalytic triad (H, D, and S). Similarity analysis shows that Es-CLSP shares high identity with CLSPs from the fiddler crab Uca pugilator. Es-CLSP mRNA expression in E. sinensis is a) tissue-related with the highest expression in hemocytes and widely distributed, b) highly responsive to Vibrio anguillarum challenge in hemocytes, and c) a different response to the intruding pathogens. The results of this study demonstrate the successful isolation of Es-CLSP and indicate that Es-CLSP is an immune-related gene, and show the possible role of CLSP in the invertebrate innate immune system. PMID:24841909

  12. Plasmid-related quinolone resistance determinants in epidemic Vibrio parahaemolyticus, uropathogenic Escherichia coli, and marine bacteria from an aquaculture area in Chile.

    PubMed

    Aedo, Sandra; Ivanova, Larisa; Tomova, Alexandra; Cabello, Felipe C

    2014-08-01

    Marine bacteria from aquaculture areas with industrial use of quinolones have the potential to pass quinolone resistance genes to animal and human pathogens. The VPA0095 gene, related to the quinolone resistance determinant qnrA, from clinical isolates of epidemic Vibrio parahaemolyticus conferred reduced susceptibility to quinolone after cloning into Escherichia coli K-12 either when acting alone or synergistically with DNA gyrase mutations. In addition, a plasmid-mediated quinolone resistance gene from marine bacteria, aac(6')-Ib-cr, was identical to aac(6')-Ib-cr from urinary tract isolates of E. coli, suggesting a recent flow of this gene between these bacteria isolated from different environments. aac(6')-Ib-cr from E. coli also conferred reduced susceptibility to quinolone and kanamycin when cloned into E. coli K-12. PMID:24760167

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

    PubMed

    González, Yael; Camarena, Laura; Dreyfus, Georges

    2015-03-01

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

  14. Characterization of Vibrio fluvialis-Like Strains Implicated in Limp Lobster Disease

    PubMed Central

    Tall, B. D.; Fall, S.; Pereira, M. R.; Ramos-Valle, M.; Curtis, S. K.; Kothary, M. H.; Chu, D. M. T.; Monday, S. R.; Kornegay, L.; Donkar, T.; Prince, D.; Thunberg, R. L.; Shangraw, K. A.; Hanes, D. E.; Khambaty, F. M.; Lampel, K. A.; Bier, J. W.; Bayer, R. C.

    2003-01-01

    Studies were undertaken to characterize and determine the pathogenic mechanisms involved in a newly described systemic disease in Homarus americanus (American lobster) caused by a Vibrio fluvialis-like microorganism. Nineteen isolates were obtained from eight of nine lobsters sampled. Biochemically, the isolates resembled V. fluvialis, and the isolates grew optimally at 20°C; none could grow at temperatures above 23°C. The type strain (1AMA) displayed a thermal reduction time (D value) of 5.77 min at 37°C. All of the isolates required at least 1% NaCl for growth. Collectively, the data suggest that these isolates may embody a new biotype. Pulsed-field gel electrophoresis (PFGE) analysis of the isolates revealed five closely related subgroups. Some isolates produced a sheep hemagglutinin that was neither an outer membrane protein nor a metalloprotease. Several isolates possessed capsules. The isolates were highly susceptible to a variety of antibiotics tested. However, six isolates were resistant to erythromycin. Seventeen isolates harbored plasmids. Lobster challenge studies revealed that the 50% lethal dose of a plasmid-positive strain was 100-fold lower than that of a plasmid-negative strain, suggesting that the plasmid may enhance the pathogenicity of these microorganisms in lobsters. Microorganisms that were recovered from experimentally infected lobsters exhibited biochemical and PFGE profiles that were indistinguishable from those of the challenge strain. Tissue affinity studies demonstrated that the challenge microorganisms accumulated in heart and midgut tissues as well as in the hemolymph. Culture supernatants and polymyxin B lysates of the strains caused elongation of CHO cells in tissue culture, suggesting the presence of a hitherto unknown enterotoxin. Both plasmid-positive and plasmid-negative strains caused significant dose-related intestinal fluid accumulations in suckling mice. Absence of viable organisms in the intestinal contents of mice suggests that these microorganisms cause diarrhea in mice by intoxication rather than by an infectious process. Further, these results support the thermal reduction data at 37°C and suggest that the mechanism(s) that led to fluid accumulation in mice differs from the disease process observed in lobsters by requiring neither the persistence of viable microorganisms nor the presence of plasmids. In summary, results of lobster studies satisfy Koch's postulates at the organismal and molecular levels; the findings support the hypothesis that these V. fluvialis-like organisms were responsible for the originally described systemic disease, which is now called limp lobster disease. PMID:14660396

  15. Molecular Typing of Vibrio cholerae O1 Isolates from Thailand by Pulsed-field Gel Electrophoresis

    PubMed Central

    Tapchaisri, Pramuan; Na-Ubol, Mathukorn; Tiyasuttipan, Watcharee; Chaiyaroj, Sansanee C.; Yamasaki, Shinji; Wongsaroj, Thitima; Hayashi, Hideo; Nair, G. Balakrish; Chongsa-Nguan, Manas; Kurazono, Hisao; Chaicumpa, Wanpen

    2008-01-01

    The aim of the present study was to genotypically characterize Vibrio cholerae strains isolated from cholera patients in various provinces of Thailand. Two hundred and forty V. cholerae O1 strains, isolated from patients with cholera during two outbreaks, i.e. March 1999–April 2000 and December 2001–February 2002, in Thailand, were genotypically characterized by NotI digestion and pulsed-field gel electrophoresis (PFGE). In total, 17 PFGE banding patterns were found and grouped into four Dice-coefficient clusters (PF-I to PF-IV). The patterns of V. cholerae O1, El Tor reference strains from Australia, Peru, Romania, and the United States were different from the patterns of reference isolates from Asian countries, such as Bangladesh, India, and Thailand, indicating a close genetic relationship or clonal origin of the isolates in the same geographical region. The Asian reference strains, regardless of their biotypes and serogroups (classical O1, El Tor O1, O139, or O151), showed a genetic resemblance, but had different patterns from the strains collected during the two outbreaks in Thailand. Of 200 Ogawa strains collected during the first outbreak in Thailand, two patterns (clones)—PF-I and PF-II—predominated, while other isolates caused sporadic cases and were grouped together as pattern PF-III. PF-II also predominated during the second outbreak, but none of the 40 isolates (39 Inaba and 1 Ogawa) of the second outbreak had the pattern PF-I; a minority showed a new pattern—PF-IV, and others caused single cases, but were not groupable. In summary, this study documented the sustained appearance of the pathogenic V. cholerae O1 clone PF-II, the disappearance of clones PF-I and PF-III, and the emergence of new pathogenic clones during the two outbreaks of cholera. Data of the study on molecular characteristics of indigenous V. cholerae clinical isolates have public-health implications, not only for epidemic tracing of existing strains but also for the recognition of strains with new genotypes that may emerge in the future. PMID:18637531

  16. Characterization of trh2 Harbouring Vibrio parahaemolyticus Strains Isolated in Germany

    PubMed Central

    Bechlars, Silke; Jäckel, Claudia; Diescher, Susanne; Wüstenhagen, Doreen A.; Kubick, Stefan; Dieckmann, Ralf; Strauch, Eckhard

    2015-01-01

    Background Vibrio parahaemolyticus is a recognized human enteropathogen. Thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH) as well as the type III secretion system 2 (T3SS2) are considered as major virulence factors. As tdh positive strains are not detected in coastal waters of Germany, we focused on the characterization of trh positive strains, which were isolated from mussels, seawater and patients in Germany. Results Ten trh harbouring V. parahaemolyticus strains from Germany were compared to twenty-one trh positive strains from other countries. The complete trh sequences revealed clustering into three different types: trh1 and trh2 genes and a pseudogene ?trh. All German isolates possessed alleles of the trh2 gene. MLST analysis indicated a close relationship to Norwegian isolates suggesting that these strains belong to the autochthonous microflora of Northern Europe seawaters. Strains carrying the pseudogene ?trh were negative for T3SS2? effector vopC. Transcription of trh and vopC genes was analyzed under different growth conditions. Trh2 gene expression was not altered by bile while trh1 genes were inducible. VopC could be induced by urea in trh2 bearing strains. Most trh1 carrying strains were hemolytic against sheep erythrocytes while all trh2 positive strains did not show any hemolytic activity. TRH variants were synthesized in a prokaryotic cell-free system and their hemolytic activity was analyzed. TRH1 was active against sheep erythrocytes while TRH2 variants were not active at all. Conclusion Our study reveals a high diversity among trh positive V. parahaemolyticus strains. The function of TRH2 hemolysins and the role of the pseudogene ?trh as pathogenicity factors are questionable. To assess the pathogenic potential of V. parahaemolyticus strains a differentiation of trh variants and the detection of T3SS2? components like vopC would improve the V. parahaemolyticus diagnostics and could lead to a refinement of the risk assessment in food analyses and clinical diagnostics. PMID:25799574

  17. Distribution of Vibrio alginolyticus-like species in Shenzhen coastal waters, China

    PubMed Central

    Chen, Ming-Xia; Li, He-Yang; Li, Gang; Zheng, Tian-Ling

    2011-01-01

    We investigated the distribution of vibrios in Shenzhen coastal waters in order to obtain valuable information for the aquaculture industry and a health warning system. Quantities of vibrios from surface waters ranged from 0 to 4.40×104 CFUs mL-1 in April (spring), while from 0 to 2.57×103 CFUs mL-1 in September (autumn); the abundance of V. alginolyticus-like species from surface water ranged from 0 to 6.72×103 CFUs mL-1 in April (spring) and from 0 to 1.28×103 CFUs mL-1 in September (autumn); higher counts were observed in spring. The V. alginolyticus-like species was dominant in Shenzhen coastal waters, with the highest abundance in the clean region (stations YMK001 and GDN064) in April, suggesting that Vibrio spp. were naturally occurring bacteria in marine environments. The correlation between the abundance of vibrios (including V. alginolyticus-like species) and environmental factors varied in different regions and different seasons. There were no vibrios detected when the salinity was less than 11.15‰ in the Zhujiang River estuary, which indicated that salinity played a key role in the distribution of vibrios and V. alginolyticus-like species. PMID:24031704

  18. Immunochemical studies on lipopolysaccharide from agglutinable and non-agglutinable vibrios.

    PubMed

    Guhathakurta, B; Dutta, G C

    1974-04-01

    Lipopolysaccharide (LPS) prepared from Vibrio cholerae and a non-agglutinable (NAG; not agglutinable with O-group I serum according to Gardner and Venkatraman [13]) vibrio strain, isolated from a patient with cholera-like clinical symptoms, have been compared with respect to their chemical composition and immunological behavior. In addition to a significant difference in the chemical composition between the two lipopolysaccharides, the LPS from V. cholerae, unlike that from the NAG vibrio, requires prior treatment with alkali for it to be an effective antigen in the indirect hemagglutination test with sheep cells. It has been suggested that the alkali acts by removing excess O-acetyl group from LPS of agglutinable vibrios. LPS from the NAG vibrio consistently showed a lower antibody response in rabbits in terms of agglutinin and vibriocidal titer. Also, the class of agglutinin antibody elicited by LPS of the NAG vibrio was predominantly immunoglobin M, and that from V. cholerae was immunoglobulin G under comparable conditions. PMID:4207760

  19. Immunochemical Studies on Lipopolysaccharide from Agglutinable and Non-Agglutinable Vibrios

    PubMed Central

    Guhathakurta, Bhakti; Dutta, G. C.

    1974-01-01

    Lipopolysaccharide (LPS) prepared from Vibrio cholerae and a non-agglutinable (NAG; not agglutinable with O-group I serum according to Gardner and Venkatraman [13]) vibrio strain, isolated from a patient with cholera-like clinical symptoms, have been compared with respect to their chemical composition and immunological behavior. In addition to a significant difference in the chemical composition between the two lipopolysaccharides, the LPS from V. cholerae, unlike that from the NAG vibrio, requires prior treatment with alkali for it to be an effective antigen in the indirect hemagglutination test with sheep cells. It has been suggested that the alkali acts by removing excess O-acetyl group from LPS of agglutinable vibrios. LPS from the NAG vibrio consistently showed a lower antibody response in rabbits in terms of agglutinin and vibriocidal titer. Also, the class of agglutinin antibody elicited by LPS of the NAG vibrio was predominantly immunoglobin M, and that from V. cholerae was immunoglobulin G under comparable conditions. PMID:4207760

  20. A critical role for hemolysin in Vibrio fluvialis-induced IL-1? secretion mediated by the NLRP3 inflammasome in macrophages

    PubMed Central

    Song, Liqiong; Huang, Yuanming; Zhao, Meng; Wang, Zhihao; Wang, Shujing; Sun, Hui; Kan, Biao; Meng, Guangxun; Liang, Weili; Ren, Zhihong

    2015-01-01

    Vibrio fluvialis causes human diarrhea, but the pathogenesis is not well-studied. We hypothesized that V. fluvialis-secreted hemolysin (VFH) may induce IL-1? secretion through the activation of the NLRP3 inflammasome and contribute to the pathogenicity of V. fluvialis. To examine this possibility, we constructed VFH mutant and complement strains and demonstrated that V. fluvialis-induced IL-1? production and cytotoxicity in human monocytic THP-1 cells and mouse macrophages is attributed to VFH. To evaluate the role of VFH in vivo, we infected adult C57BL/6 mice intraperitoneally and suckling C57/B6 mice orally with various strains. The mice treated with 108 CFU wild-type V. fluvialis or cell-free supernatant containing VFH induced significantly higher IL-1? production in peritoneal lavage fluid or in colon compared with those infected with the mutant strain, while no effect on TNF and IL-6 production was observed at day 5 or 24 h post-infection. VFH contributed to pathological changes and IL-1? release independent of colonization of V. fluvialis in the colon. VFH has no effect on the synthesis of pro-IL-1?, but rather it triggers the processing of pro-IL-1? into IL-1?. Furthermore, using deficient mouse strains, we verified that V. fluvialis-induced IL-1? is mediated through activation of Caspase-1 and the NLRP3 inflammasome ex vivo. Confocal microscopy suggests that VFH contributes to cathepsin B release. Furthermore, V. fluvialis-induced IL-1? secretion requires potassium (K+) e?ux and reactive oxygen species production. Our results provide new evidence for the role of VFH in the activation of the NLRP3 inflammasome and pathogenesis in response to V. fluvialis infection. Summary Sentence: Vibrio fluvialis-secreted hemolysin induces IL-1? secretion through the activation of the NLRP3 inflammasome and contributes to the pathogenicity of V. fluvialis.

  1. Global surveillance of antibiotic sensitivity of Vibrio cholerae*

    PubMed Central

    O'Grady, F.; Lewis, M. J.; Pearson, N. J.

    1976-01-01

    Strains of Vibrio cholerae—1156 from various parts of the world—were examined by standardized antibiotic sensitivity tests in one centre, to determine the global incidence of antibiotic resistance in this organism and to assess the extent to which differences in methods of sensitivity testing might be responsible for discrepancies in the reported incidence of resistant strains. Of the strains examined, 1127 were fully sensitive to ampicillin, chloramphenicol, tetracycline, furazolidone, and three different sulphonamides, 27 showed stable and reproducible resistance to one or more of these agents, and 2 proved to contain a minority of cells with unstable, presumably plasmid-borne, resistance to chloram-phenicol. Unstable resistance to antibiotics may be common in V. cholerae but rarely recognized, and may account for some of the discrepancies in the reported incidence of resistant strains. PMID:1088100

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

    PubMed Central

    Pukatzki, Stefan; Provenzano, Daniele

    2013-01-01

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

  3. Environmental reservoirs and mechanisms of persistence of Vibrio cholerae

    PubMed Central

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

    2013-01-01

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

  4. Studies on the haemolytic activity of El Tor vibrios*

    PubMed Central

    Feeley, John. C.; Pittman, Margaret

    1963-01-01

    In view of reports of inconsistent results with the haemolytic test for identification of the El Tor biotype of Vibrio cholerae, a study was made of the experimental variables involved in order to achieve more precise standardization of the procedure. It was found that different types of media and different incubation times of a culture in a particular medium exerted a profound influence on the results. The authors describe the materials and conditions for performance of a reliable haemolytic test, and consider that, when properly performed, the haemolytic test should be a valuable epidemiological tool. The persistence of haemolysin in cultures of strains from the El Tor Quarantine Station during incubation is in contrast to its early disappearance in cultures of more recent isolates. Evidence is presented that the haemolytic activity of a strain may become altered during subculture, since rugose variants of recent strains resemble the old El Tor strains in haemolysin persistence. PMID:13944689

  5. Introduction to Pathogenic Bacteria

    Microsoft Academic Search

    Tracey Elizabeth Love; Barbara Jones

    This chapter is a brief introduction to pathogenic microorganisms and also discusses virulence factors. An understanding of\\u000a virulence factors is important, as they represent potential targets for the detection of microbial pathogens. Sources and\\u000a routes of infection are also briefly discussed with reference to specific examples. There are a number of ways in which infection\\u000a could be acquired, including via

  6. Effect of water storage in silver container on the viability of enteric bacterial pathogens.

    PubMed

    Kotigadde, Subbannayya; Anusha, G R; Sandya, V; Subbannayya, Yashwanth; Subbannayya, Tejaswini; Nayak, Shivananda

    2012-12-01

    Silver is one of the heavy metals traditionally played major role in the human life. It is used in the form of ornaments or as containers to store or drink water and other consumable liquids. The study was designed to observe the effect of water storage in silver containers on enteric pathogens. Three sets of sterile silver, stainless steel and glass metal screw capped containers were filled with non-chlorinated sterilized well water. One each of the three sets was inoculated with enteric pathogens viz. Shigella dysenteriae, Vibrio cholerae O1 and Salmonella typhi cultures drawn from the laboratory stock and incubated at 37 degrees C for varying periods. Preliminary findings of this study indicated that silver is bactericidal within an hour to Shigella dysenteriae, Vibrio cholerae O1 and Salmonella typhi which cause life-threatening enteric human diseases. The quantity of silver needed to eliminate these bacteria was found to be less than 2.5 ug/dl at pH 6.5. This study reveals the potential for silver containers to be used to disinfect natural water in areas of poor hygiene and sanitation where groundwater is the main source of drinking water. PMID:25145073

  7. Human Pathogen Importation Importing "Human" Pathogens from Outside Canada

    E-print Network

    Human Pathogen Importation Importing "Human" Pathogens from Outside Canada 1) Permits are not required for Risk Group 1 materals. If the material is deemed to be non- pathogenic, a courtesy notice may is required from PHAC*, please go to the PHAC website at http://www.phac- aspc.gc.ca/ols-bsl/pathogen

  8. BTI Pathogen Use Committee BTI Pathogen Use Form

    E-print Network

    Pawlowski, Wojtek

    BTI Pathogen Use Committee 4/7/04 1 BTI Pathogen Use Form Date Submitted: Date Received by PUC for space, if appropriate. 1. Are you planning to use recombinant pathogens in the BTI Plant Growth facilities? Yes No If yes, provide permit # of approved IBC r DNA MUA and attach copy. 2. List all pathogens

  9. Chitin-Induced Carbotype Conversion in Vibrio vulnificus?†

    PubMed Central

    Neiman, Jana; Guo, Yunzhi; Rowe-Magnus, Dean A.

    2011-01-01

    As an etiological agent of bacterial sepsis and wound infections, Vibrio vulnificus is unique among the Vibrionaceae. The most intensely studied of its virulence factors is the capsular polysaccharide (CPS). Over 100 CPS types have been identified, yet little is known about the genetic mechanisms that drive such diversity. Chitin, the second-most-abundant polysaccharide in nature, is known to induce competence in Vibrio species. Here, we show that the frequency of chitin-induced transformation in V. vulnificus varies by strain and that (GlcNAc)2 is the shortest chitin-derived polymer capable of inducing competence. Transformation frequencies (TFs) increased 8-fold when mixed-culture biofilms were exposed to a strain-specific lytic phage, suggesting that the lysis of dead cells during lytic infection increased the amount of extracellular DNA within the biofilm that was available for transfer. Furthermore, we show that V. vulnificus can undergo chitin-dependent carbotype conversion following the uptake and recombination of complete cps loci from exogenous genomic DNA (gDNA). The acquisition of a partial locus was also demonstrated when internal regions of homology between the endogenous and exogenous loci existed. This suggested that the same mechanism governing the transfer of complete cps loci also contributed to their evolution by generating novel combinations of CPS biosynthesis genes. Since no evidence that cps loci were preferentially acquired during natural transformation (random transposon-tagged DNA was readily taken up in chitin transformation assays) exists, the phenomenon of chitin-induced transformation likely plays an important but general role in the evolution of this genetically promiscuous genus. PMID:21670169

  10. Chitin-induced carbotype conversion in Vibrio vulnificus.

    PubMed

    Neiman, Jana; Guo, Yunzhi; Rowe-Magnus, Dean A

    2011-08-01

    As an etiological agent of bacterial sepsis and wound infections, Vibrio vulnificus is unique among the Vibrionaceae. The most intensely studied of its virulence factors is the capsular polysaccharide (CPS). Over 100 CPS types have been identified, yet little is known about the genetic mechanisms that drive such diversity. Chitin, the second-most-abundant polysaccharide in nature, is known to induce competence in Vibrio species. Here, we show that the frequency of chitin-induced transformation in V. vulnificus varies by strain and that (GlcNAc)(2) is the shortest chitin-derived polymer capable of inducing competence. Transformation frequencies (TFs) increased 8-fold when mixed-culture biofilms were exposed to a strain-specific lytic phage, suggesting that the lysis of dead cells during lytic infection increased the amount of extracellular DNA within the biofilm that was available for transfer. Furthermore, we show that V. vulnificus can undergo chitin-dependent carbotype conversion following the uptake and recombination of complete cps loci from exogenous genomic DNA (gDNA). The acquisition of a partial locus was also demonstrated when internal regions of homology between the endogenous and exogenous loci existed. This suggested that the same mechanism governing the transfer of complete cps loci also contributed to their evolution by generating novel combinations of CPS biosynthesis genes. Since no evidence that cps loci were preferentially acquired during natural transformation (random transposon-tagged DNA was readily taken up in chitin transformation assays) exists, the phenomenon of chitin-induced transformation likely plays an important but general role in the evolution of this genetically promiscuous genus. PMID:21670169

  11. Effectors of animal and plant pathogens use a common domain to bind host phosphoinositides.

    PubMed

    Salomon, Dor; Guo, Yirui; Kinch, Lisa N; Grishin, Nick V; Gardner, Kevin H; Orth, Kim

    2013-01-01

    Bacterial Type III Secretion Systems deliver effectors into host cells to manipulate cellular processes to the advantage of the pathogen. Many host targets of these effectors are found on membranes. Therefore, to identify their targets, effectors often use specialized membrane-localization domains to localize to appropriate host membranes. However, the molecular mechanisms used by many domains are unknown. Here we identify a conserved bacterial phosphoinositide-binding domain (BPD) that is found in functionally diverse Type III effectors of both plant and animal pathogens. We show that members of the BPD family functionally bind phosphoinositides and mediate localization to host membranes. Moreover, NMR studies reveal that the BPD of the newly identified Vibrio parahaemolyticus Type III effector VopR is unfolded in solution, but folds into a specific structure upon binding its ligand phosphatidylinositol-(4,5)-bisphosphate. Thus, our findings suggest a possible mechanism for promoting refolding of Type III effectors after delivery into host cells. PMID:24346350

  12. Signature tagged mutagenesis in the functional genetic analysis of gastrointestinal pathogens

    PubMed Central

    Cummins, Joanne; Gahan, Cormac G.M.

    2012-01-01

    Signature tagged mutagenesis is a genetic approach that was developed to identify novel bacterial virulence factors. It is a negative selection method in which unique identification tags allow analysis of pools of mutants in mixed populations. The approach is particularly well suited to functional genetic analysis of the gastrointestinal phase of infection in foodborne pathogens and has the capacity to guide the development of novel vaccines and therapeutics. In this review we outline the technical principles underpinning signature-tagged mutagenesis as well as novel sequencing-based approaches for transposon mutant identification such as TraDIS (transposon directed insertion-site sequencing). We also provide an analysis of screens that have been performed in gastrointestinal pathogens which are a global health concern (Escherichia coli, Listeria monocytogenes, Helicobacter pylori, Vibrio cholerae and Salmonella enterica). The identification of key virulence loci through the use of signature tagged mutagenesis in mice and relevant larger animal models is discussed. PMID:22555467

  13. Early steps in the European eel (Anguilla anguilla)-Vibrio vulnificus interaction in the gills: role of the RtxA13 toxin.

    PubMed

    Callol, Agnès; Pajuelo, David; Ebbesson, Lars; Teles, Mariana; MacKenzie, Simon; Amaro, Carmen

    2015-04-01

    Vibrio vulnificus is an aquatic gram-negative bacterium that causes a systemic disease in eels called warm-water vibriosis. Natural disease occurs via water born infection; bacteria attach to the gills (the main portal of entry) and spread to the internal organs through the bloodstream, provoking host death by haemorrhagic septicaemia. V. vulnificus produces a toxin called RtxA13 that hypothetically interferes with the eel immune system facilitating bacterial invasion and subsequent death by septic shock. The aim of this work was to study the early steps of warm-water vibriosis by analysing the expression of three marker mRNA transcripts related to pathogen recognition (tlr2 and tlr5) and inflammation (il-8) in the gills of eels infected by immersion with either the pathogen or a mutant deficient in rtxA13. Results indicate a differential response that is linked to the rtx toxin in the expression levels of the three measured mRNA transcripts. The results suggest that eels are able to distinguish innocuous from harmful microorganisms by the local action of their toxins rather than by surface antigens. Finally, the cells that express these transcripts in the gills are migratory cells primarily located in the second lamellae that re-locate during infection suggesting the activation of a specific immune response to pathogen invasion in the gill. PMID:25613341

  14. A repeat unit of Vibrio diarrheal T3S effector subverts cytoskeletal actin homeostasis via binding to interstrand region of actin filaments.

    PubMed

    Nishimura, Mitsuhiro; Fujii, Takashi; Hiyoshi, Hirotaka; Makino, Fumiaki; Inoue, Hajime; Motooka, Daisuke; Kodama, Toshio; Ohkubo, Tadayasu; Kobayashi, Yuji; Nakamura, Shota; Namba, Keiichi; Iida, Tetsuya

    2015-01-01

    A novel bacterial type III secretion effector, VopV, from the enteric pathogen Vibrio parahaemolyticus has been identified as a key factor in pathogenicity due to its interaction with cytoskeletal actin. One of the repeat units in the long repetitive region of VopV, named VopVrep1, functions as an actin-binding module. Despite its importance in pathogenesis, the manner in which the effector binds to actin and the subsequent effects on actin dynamics remain unclear. Here, we report the molecular basis of the VopVrep1/actin interaction. VopVrep1 exists as an unstructured protein in solution but potently and specifically binds filamentous actin (F-actin) and not globular actin (G-actin). The F-actin/VopVrep1 complex was directly visualized at 9.6-Å resolution using electron cryomicroscopy (cryoEM) and helical image reconstitution. The density map revealed the binding site of VopVrep1 at the interface between two actin strands, which is close to the binding site of the bicyclic heptapeptide toxin phalloidin. Consistent with this observation, VopVrep1 alone prevented the depolymerization of F-actin. Overall, VopVrep1 demonstrated unique characteristics in comparison to known actin-binding proteins, but was relatively similar to phalloidin. The phalloidin-like behavior, targeting the interstrand region of actin filaments to stabilize the filament structure, likely contributes to the pathogenicity of V. parahaemolyticus. PMID:26039684

  15. Enzymatic, outer membrane proteins and plasmid alterations of starved Vibrio parahaemolyticus and Vibrio alginolyticus cells in seawater.

    PubMed

    Abdallah, Fethi Ben; Kallel, Héla; Bakhrouf, Amina

    2009-06-01

    The marine bacteria Vibrio parahaemolyticus and V. alginolyticus were incubated in seawater for 8 months to evaluate their adaptative responses to starvation. The starved cells showed an altered biochemical and enzymatic profiles, respectively, on Api 20E and Api ZYM systems and an evolution to the filterable minicells state capable to pass membrane pore size 0.45 microm. Outer membrane proteins patterns of stressed bacteria were also altered. Indeed, these modifications were manifested by the appearance and/or disappearance of bands as well as in the level of expression of certain proteins. Plasmids profiles analysis showed that V. alginolyticus ATCC 33787 lost three plasmids, whereas other tested strains conserved their initial profiles. PMID:19373459

  16. Comparison of the Growth and Survival of Larval Turbot in the Absence of Culturable Bacteria with Those in the Presence of Vibrio anguillarum, Vibrio alginolyticus, or a Marine Aeromonas sp

    PubMed Central

    Munro, P. D.; Barbour, A.; Birkbeck, T. H.

    1995-01-01

    Larval turbot (Scophthalmus maximus) were reared on rotifers (Brachionus plicatilis) in the absence of culturable bacteria for up to 14 days and exhibited growth and high rates of survival (>55% in five experiments). Low numbers of known bacteria were introduced into similar cultures by exposure of the rotifers to a suspension of bacteria prior to addition of rotifers to the larval cultures; Vibrio anguillarum 91079 caused a highly significant decrease (P <0.01) in the proportion of survivors in two separate trials. With an Aeromonas sp. previously isolated from a healthy batch of copepod-fed larvae, there was no significant difference in survival compared with control larvae, even though the density of bacteria in the water of larval cultures reached 10(sup7) ml(sup-1). Bacteria colonized the gut of larvae exposed to Aeromonas-treated rotifers to levels similar to those in conventionally reared fish (>4 x 10(sup4) CFU per larva). Rearing of larvae in the presence of known bacteria provides a means of investigating the interaction of specific bacteria with turbot larvae and could provide a method for the selection of bacteria which may restrict the growth of opportunistic pathogens which would be harmful to turbot larvae. PMID:16535196

  17. Will the package contain pathogens

    E-print Network

    Will the package contain pathogens OR dry ice ? Is the material considered hazardous by the DOT? Do ? NO NO YES YES Pack and ship. If you have identified any hazardous pathogenic substances, ensure you take EHS to a location outside of the US, and: - The materials are pathogens listed on Stanford's Dual Use Pathogen List

  18. A comprehensive Prunus pathogen array

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A comprehensive pathogen array was developed for the detection of pathogens of many major crops in the Prunus genus. The APS disease lists for peach, plum, apricot and cherry were combined into a single Prunus pathogen list, containing 102 pathogens (75 fungi, 18 viruses, 6 bacteria and 3 phytoplasm...

  19. Pathogenic bacteria associated with oysters (Crassostrea brasiliana) and estuarine water along the south coast of Brazil.

    PubMed

    Ristori, Christiane A; Iaria, Sebastião T; Gelli, Dilma S; Rivera, Irma N G

    2007-08-01

    Oysters and estuarine water samples were collected monthly, from June 1998 to March 1999, in the Cananéia estuary, on the south coast of São Paulo, Brazil, and analyzed for bacterial hazards with and without depuration in filtered estuarine water. Aeromonas spp., Plesiomonas shigelloides, Vibrio cholerae O1, Vibrio parahaemolyticus, and Vibrio vulnificus were counted in oyster samples using the most probable number (MPN) and their presence verified in the surrounding estuarine water samples. The presence of Salmonella, Shigella, Escherichia coli O157:H7, and fecal coliforms counts were determined in oysters and in water samples too. Sixty percent of water samples contained fecal coliforms ranging from <1 to >200 CFU/100 ml and 100%, 30%, 20% and 10% were positive for V. parahaemolyticus, Salmonella, Aeromonas, and V. vulnificus in 5 l of water samples, respectively. In oyster samples, the fecal coliforms concentration ranged from <3.0 to > or =2.4 x 10(3) MPN/g in 40% of untreated and from <3.0 to 1.1 x 10(3) MPN/g in 40% of treated samples. Vibrio parahaemolyticus Kanagawa-negative was detected in all oyster samples and their concentration varied from 3.6 to > or =2.4 x 10(3) MPN/g. For the untreated oyster samples 80%, 70%, and 10% were positive for V. vulnificus (<3 - 11.0 MPN/g), Aeromonas (<3-15 MPN/g), and Salmonella (presence in 25 g), respectively. However, for treated oyster samples 60%, 30%, and 0% of them contained the same bacteria, respectively. Escherichia coli O157:H7, Shigella spp., P. shigelloides, and V. cholerae O1 were not detected in any of the samples. Fecal indicators did not correlate with Vibrio presence (p>0.05), although the isolation of Aeromonas species had a positive correlation (p = 0.017). The results showed no correlation between temperature, salinity, and bacteria (p > 0.05). The comparison between bacterial concentration in treated and untreated oyster samples, showed that only Aeromonas was higher in untreated oyster samples (p = 0.039). This study contributes toward creating a more global understanding of food-borne bacterial pathogens. The presence and concentration of viable bacterial hazards in oysters and water surrounding areas was determined for the first time on the south coast of São Paulo and it helps to define better the true microbial hazard in the aquatic environment and oysters. PMID:17613090

  20. Simultaneous Detection of Multiple Fish Pathogens Using a Naked-Eye Readable DNA Microarray

    PubMed Central

    Chang, Chin-I; Hung, Pei-Hsin; Wu, Chia-Che; Cheng, Ta Chih; Tsai, Jyh-Ming; Lin, King-Jung; Lin, Chung-Yen

    2012-01-01

    We coupled 16S rDNA PCR and DNA hybridization technology to construct a microarray for simultaneous detection and discrimination of eight fish pathogens (Aeromonas hydrophila, Edwardsiella tarda, Flavobacterium columnare, Lactococcus garvieae, Photobacterium damselae, Pseudomonas anguilliseptica, Streptococcus iniae and Vibrio anguillarum) commonly encountered in aquaculture. The array comprised short oligonucleotide probes (30 mer) complementary to the polymorphic regions of 16S rRNA genes for the target pathogens. Targets annealed to the microarray probes were reacted with streptavidin-conjugated alkaline phosphatase and nitro blue tetrazolium/5-bromo-4-chloro-3?-indolylphosphate, p-toluidine salt (NBT/BCIP), resulting in blue spots that are easily visualized by the naked eye. Testing was performed against a total of 168 bacterial strains, i.e., 26 representative collection strains, 81 isolates of target fish pathogens, and 61 ecologically or phylogenetically related strains. The results showed that each probe consistently identified its corresponding target strain with 100% specificity. The detection limit of the microarray was estimated to be in the range of 1 pg for genomic DNA and 103 CFU/mL for pure pathogen cultures. These high specificity and sensitivity results demonstrate the feasibility of using DNA microarrays in the diagnostic detection of fish pathogens. PMID:22736973

  1. Enteric bacterial pathogen detection in southern sea otters (Enhydra lutris nereis) is associated with coastal urbanization and freshwater runoff

    PubMed Central

    Miller, Melissa A.; Byrne, Barbara A.; Jang, Spencer S.; Dodd, Erin M.; Dorfmeier, Elene; Harris, Michael D.; Ames, Jack; Paradies, David; Worcester, Karen; Jessup, David A.; Miller, Woutrina A.

    2009-01-01

    Although protected for nearly a century, California’s sea otters have been slow to recover, in part due to exposure to fecally-associated protozoal pathogens like Toxoplasma gondii and Sarcocystis neurona. However, potential impacts from exposure to fecal bacteria have not been systematically explored. Using selective media, we examined feces from live and dead sea otters from California for specific enteric bacterial pathogens (Campylobacter, Salmonella, Clostridium perfringens, C. difficile and Escherichia coli O157:H7), and pathogens endemic to the marine environment (Vibrio cholerae, V. parahaemolyticus and Plesiomonas shigelloides). We evaluated statistical associations between detection of these pathogens in otter feces and demographic or environmental risk factors for otter exposure, and found that dead otters were more likely to test positive for C. perfringens, Campylobacter and V. parahaemolyticus than were live otters. Otters from more urbanized coastlines and areas with high freshwater runoff (near outflows of rivers or streams) were more likely to test positive for one or more of these bacterial pathogens. Other risk factors for bacterial detection in otters included male gender and fecal samples collected during the rainy season when surface runoff is maximal. Similar risk factors were reported in prior studies of pathogen exposure for California otters and their invertebrate prey, suggesting that land-sea transfer and/or facilitation of pathogen survival in degraded coastal marine habitat may be impacting sea otter recovery. Because otters and humans share many of the same foods, our findings may also have implications for human health. PMID:19720009

  2. Identification of T6SS-dependent effector and immunity proteins by Tn-seq in Vibrio cholerae

    PubMed Central

    Dong, Tao G.; Ho, Brian T.; Yoder-Himes, Deborah R.; Mekalanos, John J.

    2013-01-01

    Type VI protein secretion system (T6SS) is important for bacterial competition through contact-dependent killing of competitors. T6SS delivers effectors to neighboring cells and corresponding antagonistic proteins confer immunity against effectors that are delivered by sister cells. Although T6SS has been found in more than 100 gram-negative bacteria including many important human pathogens, few T6SS-dependent effector and immunity proteins have been experimentally determined. Here we report a high-throughput approach using transposon mutagenesis and deep sequencing (Tn-seq) to identify T6SS immunity proteins in Vibrio cholerae. Saturating transposon mutagenesis was performed in wild type and a T6SS null mutant. Genes encoding immunity proteins were predicted to be essential in the wild type but dispensable in the T6SS mutant. By comparing the relative abundance of each transposon mutant in the mutant library using deep sequencing, we identified three immunity proteins that render protection against killing by T6SS predatory cells. We also identified their three cognate T6SS-secreted effectors and show these are important for not only antibacterial and antieukaryotic activities but also assembly of T6SS apparatus. The lipase and muramidase T6SS effectors identified in this study underscore the diversity of T6SS-secreted substrates and the distinctly different mechanisms that target these for secretion by the dynamic T6SS organelle. PMID:23362380

  3. Efficacy of low-temperature high hydrostatic pressure processing in inactivating Vibrio parahaemolyticus in culture suspension and oyster homogenate.

    PubMed

    Phuvasate, Sureerat; Su, Yi-Cheng

    2015-03-01

    Culture suspensions of five clinical and five environmental Vibrio parahaemolyticus strains in 2% NaCl solution were subjected to high pressure processing (HPP) under various conditions (200-300MPa for 5 and 10 min at 1.5-20°C) to study differences in pressure resistance among the strains. The most pressure-resistant and pressure-sensitive strains were selected to investigate the effects of low temperatures (15, 5 and 1.5°C) on HPP (200 or 250MPa for 5 min) to inactivate V. parahaemolyticus in sterile oyster homogenates. Inactivation of V. parahaemolyticus cells in culture suspensions and oyster homogenates was greatly enhanced by lowering the processing temperature from 15 to 5 or 1.5°C. A treatment of oyster homogenates at 250MPa for 5 min at 5°C decreased the populations of V. parahaemolyticus by 6.2logCFU/g for strains 10290 and 100311Y11 and by >7.4logCFU/g for strain 10292. Decreasing the processing temperature of the same treatment to 1.5°C reduced all the V. parahaemolyticus strains inoculated to oyster homogenates to non-detectable (<10CFU/g) levels. Factors including pressure level, processing temperature and time all need to be considered for developing effective HPP for eliminating pathogens from foods. Further studies are needed to validate the efficacy of the HPP (250MPa for 5 min at 1.5°C) in inactivating V. parahaemolyticus cells in whole oysters. PMID:25498471

  4. Factors other than metalloprotease are required for full virulence of French Vibrio tubiashii isolates in oyster larvae.

    PubMed

    Mersni-Achour, Rachida; Cheikh, Yosra Ben; Pichereau, Vianney; Doghri, Ibtissem; Etien, Cédric; Dégremont, Lionel; Saulnier, Denis; Fruitier-Arnaudin, Ingrid; Travers, Marie-Agnès

    2015-05-01

    Vibrio tubiashii is a marine pathogen isolated from larval and juvenile bivalve molluscs that causes bacillary necrosis. Recent studies demonstrated the isolation of this species in a French experimental hatchery/nursery affecting Crassostrea gigas spat in 2007. Here, using larvae of C. gigas as an interaction model, we showed that the French V. tubiashii is virulent to larvae and can cause bacillary necrosis symptoms with an LD50 of about 2.3×10(3) c.f.u. ml(-1) after 24 h. Moreover, complete or gel permeation HPLC fractionated extracellular products (ECPs) of this strain appeared toxic to larvae. MS-MS analysis of the different ECP fractions revealed the existence of an extracellular metalloprotease and other suspected virulence factors. This observation is also supported by the expression level of some potential virulence factors. The overall results suggest that the pathology caused by the French V. tubiashii in C. gigas oysters is caused by a group of toxic factors and not only the metalloprotease. PMID:25701736

  5. Sediment and vegetation as reservoirs of Vibrio vulnificus in the Tampa Bay Estuary and Gulf of Mexico.

    PubMed

    Chase, Eva; Young, Suzanne; Harwood, Valerie J

    2015-04-01

    The opportunistic pathogen Vibrio vulnificus occurs naturally in estuarine habitats and is readily cultured from water and oysters under warm conditions but infrequently at ambient conditions of <15°C. The presence of V. vulnificus in other habitats, such as sediments and aquatic vegetation, has been explored much less frequently. This study investigated the ecology of V. vulnificus in water by culture and quantitative PCR (qPCR) and in sediment, oysters, and aquatic vegetation by culture. V. vulnificus samples were taken from five sites around Tampa Bay, FL. Levels determined by qPCR and culture were significantly correlated (P = 0.0006; r = 0.352); however, V. vulnificus was detected significantly more frequently by qPCR (85% of all samples) compared to culture (43%). Culturable V. vulnificus bacteria were recovered most frequently from oyster samples (70%), followed by vegetation and sediment (?50%) and water (43%). Water temperature, which ranged from 18.5 to 33.4°C, was positively correlated with V. vulnificus concentrations in all matrices but sediments. Salinity, which ranged from 1 to 35 ppt, was negatively correlated with V. vulnificus levels in water and sediments but not in other matrices. Significant interaction effects between matrix and temperature support the hypothesis that temperature affects V. vulnificus concentrations differently in different matrices and that sediment habitats may serve as seasonal reservoirs for V. vulnificus. V. vulnificus levels in vegetation have not been previously measured and reveal an additional habitat for this autochthonous estuarine bacterium. PMID:25636843

  6. Cyclic-di-GMP Regulates Extracellular Polysaccharide Production, Biofilm Formation, and Rugose Colony Development by Vibrio vulnificus?

    PubMed Central

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

    2008-01-01

    Vibrio vulnificus is a human and animal pathogen that carries the highest death rate of any food-borne disease agent. It colonizes shellfish and forms biofilms on the surfaces of plankton, algae, fish, and eels. Greater understanding of biofilm formation by the organism could provide insight into approaches to decrease its load in filter feeders and on biotic surfaces and control the occurrence of invasive disease. The capsular polysaccharide (CPS), although essential for virulence, is not required for biofilm formation under the conditions used here. In other bacteria, increased biofilm formation often correlates with increased exopolysaccharide (EPS) production. We exploited the translucent phenotype of acapsular mutants to screen a V. vulnificus genomic library and identify genes that imparted an opaque phenotype to both CPS biosynthesis and transport mutants. One of these encoded a diguanylate cyclase (DGC), an enzyme that synthesizes bis-(3?-5?)-cyclic-di-GMP (c-di-GMP). This prompted us to use this DGC, DcpA, to examine the effect of elevated c-di-GMP levels on several developmental pathways in V. vulnificus. Increased c-di-GMP levels induced the production of an EPS that was distinct from the CPS and dramatically enhanced biofilm formation and rugosity in a CPS-independent manner. However, the EPS could not compensate for the loss of CPS production that is required for virulence. In contrast to V. cholerae, motility and virulence appeared unaffected by elevated levels of c-di-GMP. PMID:18487410

  7. Characterization of Vibrio cholerae bacteriophages isolated from the environmental waters of the Lake Victoria region of Kenya.

    PubMed

    Maina, Alice Nyambura; Mwaura, Francis B; Oyugi, Julius; Goulding, David; Toribio, Ana L; Kariuki, Samuel

    2014-01-01

    Over the last decade, cholera outbreaks have become common in some parts of Kenya. The most recent cholera outbreak occurred in Coastal and Lake Victoria region during January 2009 and May 2010, where a total of 11,769 cases and 274 deaths were reported by the Ministry of Public Health and Sanitation. The objective of this study is to isolate Vibrio cholerae bacteriophages from the environmental waters of the Lake Victoria region of Kenya with potential for use as a biocontrol for cholera outbreaks. Water samples from wells, ponds, sewage effluent, boreholes, rivers, and lakes of the Lake Victoria region of Kenya were enriched for 48 h at 37 °C in broth containing a an environmental strain of V. cholerae. Bacteriophages were isolated from 5 out of the 42 environmental water samples taken. Isolated phages produced tiny, round, and clear plaques suggesting that these phages were lytic to V. cholerae. Transmission electron microscope examination revealed that all the nine phages belonged to the family Myoviridae, with typical icosahedral heads, long contractile tails, and fibers. Head had an average diameter of 88.3 nm and tail of length and width 84.9 and 16.1 nm, respectively. Vibriophages isolated from the Lake Victoria region of Kenya have been characterized and the isolated phages may have a potential to be used as antibacterial agents to control pathogenic V. cholerae bacteria in water reservoirs. PMID:23982202

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

    PubMed

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

    2015-01-01

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

  9. The Vibrio cholerae Colonization Factor GbpA Possesses a Modular Structure that Governs Binding to Different Host Surfaces

    PubMed Central

    Wong, Edmond; Vaaje-Kolstad, Gustav; Ghosh, Avishek; Hurtado-Guerrero, Ramon; Konarev, Peter V.; Ibrahim, Adel F. M.; Svergun, Dmitri I.; Eijsink, Vincent G. H.; Chatterjee, Nabendu S.; van Aalten, Daan M. F.

    2012-01-01

    Vibrio cholerae is a bacterial pathogen that colonizes the chitinous exoskeleton of zooplankton as well as the human gastrointestinal tract. Colonization of these different niches involves an N-acetylglucosamine binding protein (GbpA) that has been reported to mediate bacterial attachment to both marine chitin and mammalian intestinal mucin through an unknown molecular mechanism. We report structural studies that reveal that GbpA possesses an unusual, elongated, four-domain structure, with domains 1 and 4 showing structural homology to chitin binding domains. A glycan screen revealed that GbpA binds to GlcNAc oligosaccharides. Structure-guided GbpA truncation mutants show that domains 1 and 4 of GbpA interact with chitin in vitro, whereas in vivo complementation studies reveal that domain 1 is also crucial for mucin binding and intestinal colonization. Bacterial binding studies show that domains 2 and 3 bind to the V. cholerae surface. Finally, mouse virulence assays show that only the first three domains of GbpA are required for colonization. These results explain how GbpA provides structural/functional modular interactions between V. cholerae, intestinal epithelium and chitinous exoskeletons. PMID:22253590

  10. Distribution and growth of Vibrio parahaemolyticus in southern Chilean clams (Venus antiqua) and blue mussels (Mytilus chilensis).

    PubMed

    Aranda, Carlos P; Yévenes, Marco; Rodriguez-Benito, Cristina; Godoy, Félix A; Ruiz, Magdalena; Cachicas, Viviana

    2015-01-01

    We evaluated the distribution and growth of Vibrio parahaemolyticus in the inland sea of southern Chile, where the world's largest foodborne gastroenteritis outbreak by the pandemic strain O3:K6 occurred in 2005. Intertidal samples of Mytilus chilensis and Venus antiqua were collected around port towns between 41°28'S and 43°07'S, during April to May 2011 and January to March 2012. We used most probable number real-time polymerase chain reaction (MPN-PCR) for enumeration of the tlh, tdh, and trh genes in freshly harvested bivalves and after a controlled postharvest temperature abuse. Pathogenic markers (tdh+ or trh+) were not detected. Total V. parahaemolyticus (tlh+) in freshly harvested samples reached up to 0.38 and 3.66 log MPN/g in 2011 and 2012, respectively, with values close to or above 3 log MPN/g only near Puerto Montt (41°28'S, 72°55'W). Enrichments by temperature abuse (>2 log MPN/g) occurred mainly in the same zone, regardless of the year, suggesting that both natural or anthropogenic exposure to high temperatures were more critical. Lower salinity and higher sea surface temperature in Reloncaví Sound and Reloncaví Estuary were consistent with our observations and allowed confirmation of the existence of a high-risk zone near Puerto Montt. Based on the results, a strategy focused on risk management inside this defined hazard zone is recommended. PMID:25383987

  11. Discovery and Biological Characterization of the Auromomycin Chromophore as an Inhibitor of Biofilm Formation in Vibrio cholerae

    PubMed Central

    Peach, Kelly C.; Cheng, Andrew T.; Oliver, Allen G.; Yildiz, Fitnat H.

    2013-01-01

    Bacterial biofilms pose a significant challenge in clinical environments due to their inherent lack of susceptibility to antibiotic treatment. It is widely recognized that most pathogenic bacterial strains in the clinical setting persist in the biofilm state, and are the root cause of many recrudescent infections. Discovery and development of compounds capable of either inhibiting biofilm formation or initiating biofilm dispersal may provide new therapeutic avenues for reducing the number of hospital acquired, biofilm-mediated infections. We now report the application of our recently reported image-based, high-throughput screen to the discovery of microbially-derived natural products with biofilm inhibitory activity against Vibrio cholerae. Examination of a prefractionated library of microbially-derived marine natural products has lead to the identification of a new biofilm inhibitor that is structurally unrelated to previously reported inhibitors and is one of the most potent inhibitors reported to date against V. cholerae. Combination of this compound with sub-MIC concentrations of a number of clinically relevant antibiotics was shown to improve the biofilm inhibitory efficacy of this new compound compared to monotherapy treatments, and provides evidence for the potential therapeutic benefit of biofilm inhibitors in treating persistent biofilm-mediated infections. PMID:24106077

  12. Evolution of microbial pathogens.

    PubMed Central

    Morschhäuser, J; Köhler, G; Ziebuhr, W; Blum-Oehler, G; Dobrindt, U; Hacker, J

    2000-01-01

    Various genetic mechanisms including point mutations, genetic rearrangements and lateral gene transfer processes contribute to the evolution of microbes. Long-term processes leading to the development of new species or subspecies are termed macroevolution, and short-term developments, which occur during days or weeks, are considered as microevolution. Both processes, macro- and microevolution need horizontal gene transfer, which is particularly important for the development of pathogenic microorganisms. Plasmids, bacteriophages and so-called pathogenicity islands (PAIs) play a crucial role in the evolution of pathogens. During microevolution, genome variability of pathogenic microbes leads to new phenotypes, which play an important role in the acute development of an infectious disease. Infections due to Staphylococcus epidermidis, Candida albicans and Escherichia coli will be described with special emphasis on processes of microevolution. In contrast, the development of PAIs is a process involved in macroevolution. PAIs are especially important in processes leading to new pathotypes or even species. In this review, particular attention will be given to the fact that the evolution of pathogenic microbes can be considered as a specific example for microbial evolution in general. PMID:10874741

  13. Detection of Vibrio parahaemolyticus in Shellfish by Use of Multiplexed Real-Time PCR with TaqMan Fluorescent Probes

    PubMed Central

    Ward, Linda N.; Bej, Asim K.

    2006-01-01

    We developed a multiplexed real-time PCR assay using four sets of gene-specific oligonucleotide primers and four TaqMan probes labeled with four different fluorophores in a single reaction for detection of total and pathogenic Vibrio parahaemolyticus, including the pandemic O3:K6 serotype in oysters. V. parahaemolyticus has been associated with outbreaks of food-borne gastroenteritis caused by the consumption of raw or undercooked seafood and therefore is a concern to the seafood industry and consumers. We selected specific primers and probes targeting the thermostable direct hemolysin gene (tdh) and tdh-related hemolysin gene (trh) that have been reported to be associated with pathogenesis in this organism. In addition, we targeted open reading frame 8 of phage f237 (ORF8), which is associated with a newly emerged virulent pandemic serotype of V. parahameolyticus O3:K6. Total V. parahaemolyticus was targeted using the thermolabile hemolysin gene (tlh). The sensitivity of the combined four-locus multiplexed TaqMan PCR was found to be 200 pg of purified genomic DNA and 104 CFU per ml for pure cultures. Detection of an initial inoculum of 1 CFU V. parahaemolyticus per g of oyster tissue homogenate was possible after overnight enrichment, which resulted in a concentration of 3.3 × 109 CFU per ml. Use of this method with natural oysters resulted in 17/33 samples that were positive for tlh and 4/33 samples that were positive for tdh. This assay specifically and sensitively detected total and pathogenic V. parahaemolyticus and is expected to provide a rapid and reliable alternative to conventional detection methods by reducing the analysis time and obviating the need for multiple assays. PMID:16517652

  14. A novel polyamine allosteric site of SpeG from Vibrio cholerae is revealed by its dodecameric structure.

    PubMed

    Filippova, Ekaterina V; Kuhn, Misty L; Osipiuk, Jerzy; Kiryukhina, Olga; Joachimiak, Andrzej; Ballicora, Miguel A; Anderson, Wayne F

    2015-03-27

    Spermidine N-acetyltransferase, encoded by the gene speG, catalyzes the initial step in the degradation of polyamines and is a critical enzyme for determining the polyamine concentrations in bacteria. In Escherichia coli, studies have shown that SpeG is the enzyme responsible for acetylating spermidine under stress conditions and for preventing spermidine toxicity. Not all bacteria contain speG, and many bacterial pathogens have developed strategies to either acquire or silence it for pathogenesis. Here, we present thorough kinetic analyses combined with structural characterization of the VCA0947 SpeG enzyme from the important human pathogen Vibrio cholerae. Our studies revealed the unexpected presence of a previously unknown allosteric site and an unusual dodecameric structure for a member of the Gcn5-related N-acetyltransferase superfamily. We show that SpeG forms dodecamers in solution and in crystals and describe its three-dimensional structure in several ligand-free and liganded structures. Importantly, these structural data define the first view of a polyamine bound in an allosteric site of an N-acetyltransferase. Kinetic characterization of SpeG from V. cholerae showed that it acetylates spermidine and spermine. The behavior of this enzyme is complex and exhibits sigmoidal curves and substrate inhibition. We performed a detailed non-linear regression kinetic analysis to simultaneously fit families of substrate saturation curves to uncover a simple kinetic mechanism that explains the apparent complexity of this enzyme. Our results provide a fundamental understanding of the bacterial SpeG enzyme, which will be key toward understanding the regulation of polyamine levels in bacteria during pathogenesis. PMID:25623305

  15. Genetic Relationships of Vibrio parahaemolyticus Isolates from Clinical, Human Carrier, and Environmental Sources in Thailand, Determined by Multilocus Sequence Analysis

    PubMed Central

    Theethakaew, Chonchanok; Feil, Edward J.; Castillo-Ramírez, Santiago; Aanensen, David M.; Suthienkul, Orasa; Neil, Douglas M.

    2013-01-01

    Vibrio parahaemolyticus is a seafood-borne pathogenic bacterium that is a major cause of gastroenteritis worldwide. We investigated the genetic and evolutionary relationships of 101 V. parahaemolyticus isolates originating from clinical, human carrier, and various environmental and seafood production sources in Thailand using multilocus sequence analysis. The isolates were recovered from clinical samples (n = 15), healthy human carriers (n = 18), various types of fresh seafood (n = 18), frozen shrimp (n = 16), fresh-farmed shrimp tissue (n = 18), and shrimp farm water (n = 16). Phylogenetic analysis revealed a high degree of genetic diversity within the V. parahaemolyticus population, although isolates recovered from clinical samples and from farmed shrimp and water samples represented distinct clusters. The tight clustering of the clinical isolates suggests that disease-causing isolates are not a random sample of the environmental reservoir, although the source of infection remains unclear. Extensive serotypic diversity occurred among isolates representing the same sequence types and recovered from the same source at the same time. These findings suggest that the O- and K-antigen-encoding loci are subject to exceptionally high rates of recombination. There was also strong evidence of interspecies horizontal gene transfer and intragenic recombination involving the recA locus in a large proportion of isolates. As the majority of the intragenic recombinational exchanges involving recA occurred among clinical and carrier isolates, it is possible that the human intestinal tract serves as a potential reservoir of donor and recipient strains that is promoting horizontal DNA transfer, driving evolutionary change, and leading to the emergence of new, potentially pathogenic strains. PMID:23377932

  16. Neopolyploidy and pathogen resistance

    PubMed Central

    Oswald, Benjamin P; Nuismer, Scott L

    2007-01-01

    Despite the well-documented historical importance of polyploidy, the mechanisms responsible for the establishment and evolutionary success of novel polyploid lineages remain unresolved. One possibility, which has not been previously evaluated theoretically, is that novel polyploid lineages are initially more resistant to pathogens than the diploid progenitor species. Here, we explore this possibility by developing and analysing mathematical models of interactions between newly formed polyploid lineages and their pathogens. We find that for the genetic mechanisms of pathogen resistance with the best empirical support, newly formed polyploid populations of hosts are expected to be more resistant than their diploid progenitors. This effect can be quite strong and, in the case of perennial species with recurrent polyploid formation, may last indefinitely, potentially providing a general explanation for the successful establishment of novel polyploid lineages. PMID:17686733

  17. The Keystone Pathogen Hypothesis

    PubMed Central

    Hajishengallis, George; Darveau, Richard P.; Curtis, Michael A.

    2012-01-01

    Recent studies have highlighted the importance of the human microbiome in host health and disease. However, for the most part the mechanisms by which the microbiome mediates disease, or protection from it, remain poorly understood. The “keystone pathogen” hypothesis holds that certain low-abundance microbial pathogens can orchestrate inflammatory disease by remodelling a normally benign microbiota into a dysbiotic one. In this Opinion, we critically assess the available literature in support of this hypothesis, which may provide a novel conceptual basis for the development of targeted diagnostic and treatment modalities for complex dysbiotic diseases. PMID:22941505

  18. Bloodborne Pathogens Program

    NASA Technical Reports Server (NTRS)

    Blasdell, Sharon

    1993-01-01

    The final rule on the Occupational Exposure to Bloodborne Pathogens was published in the Federal Register on Dec. 6, 1991. This Standard, 29 CFR Part 1910.130, is expected to prevent 8,900 hepatitis B infections and nearly 200 deaths a year in healthcare workers in the U.S. The Occupational Medicine and Environmental Health Services at KSC has been planning to implement this standard for several years. Various aspects of this standard and its Bloodborne Pathogens Program at KSC are discussed.

  19. An annotated cDNA library of juvenile Euprymna scolopes with and without colonization by the symbiont Vibrio fischeri

    Microsoft Academic Search

    Carlene K Chun; Todd E Scheetz; Maria de Fatima Bonaldo; Bartley Brown; Anik Clemens; Wendy J Crookes-Goodson; Keith Crouch; Tad DeMartini; Mari Eyestone; Michael S Goodson; Bernadette Janssens; Jennifer L Kimbell; Tanya A Koropatnick; Tamara Kucaba; Christina Smith; Jennifer J Stewart; Deyan Tong; Joshua V Troll; Sarahrose Webster; Jane Winhall-Rice; Cory Yap; Thomas L Casavant; Margaret J McFall-Ngai; M Bento Soares

    2006-01-01

    BACKGROUND: Biologists are becoming increasingly aware that the interaction of animals, including humans, with their coevolved bacterial partners is essential for health. This growing awareness has been a driving force for the development of models for the study of beneficial animal-bacterial interactions. In the squid-vibrio model, symbiotic Vibrio fischeri induce dramatic developmental changes in the light organ of host Euprymna

  20. PATHOGEN EQUIVALENCY COMMITTEE (PEC)

    EPA Science Inventory

    The U.S. Environmental Protection Agency created the PEC in 1985 to make recommendations to EPA and State managers on the equivalency of unproven sewage sludge disinfection technologies/processes to either a Process to Significantly Reduce Pathogens (PSRP) or a Process to Further...

  1. DISINFECTION OF EMERGING PATHOGENS

    EPA Science Inventory

    There is a growing awareness of the need to control waterborne microbial pathogens. This presentation will concentate on the role of chemical inactivation, using chlorine, chloramines and ozone as a means of controlling bacterial and protozoan species. Information will be present...

  2. Actinomycetes as plant pathogens

    Microsoft Academic Search

    Romano Locci

    1994-01-01

    Biology, taxonomy, pathogenicity and control of plant disease inducing actinomycetes are reviewed. Recent progress in the study of potato, sweet potato, blueberry and fruit and forest tree diseases is illustrated. The role in potato scab pathogenesis of the newly discovered phytotoxins, thaxtomins, is discussed.

  3. Opportunistic Pathogenic Yeasts

    NASA Astrophysics Data System (ADS)

    Banerjee, Uma

    Advances in medical research, made during the last few decades, have improved the prophylactic, diagnostic and therapeutic capabilities for variety of infections/diseases. However, many of the prophylactic and therapeutic procedures have been seen in many instances to exact a price of host-vulnerability to an expanding group of opportunistic pathogens and yeasts are one of the important members in it. Fortunately amongst the vast majority of yeasts present in nature only few are considered to have the capability to cause infections when certain opportunities predisposes and these are termed as ‘opportunistic pathogenic yeasts.’ However, the term ‘pathogenic’ is quite tricky, as it depends of various factors of the host, the ‘bug’ and the environment to manifest the clinical infection. The borderline is expanding. In the present century with unprecedented increase in number of immune-compromised host in various disciplines of health care settings, where any yeast, which has the capability to grow at 37 ° C (normal body temperature of human), can be pathogenic and cause infection in particular situation

  4. Leafhopper viral pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four newly discovered viral pathogens in leafhopper vectors of Pierce’s disease of grapes, have been shown to replicate in sharpshooter leafhoppers; the glassy-winged sharpshooter, GWSS, Homalodisca vitripennis, and Oncometopia nigricans (Hemiptera: Cicadellidae). The viruses were classified as memb...

  5. Dietary Cordyceps militaris protects against Vibrio splendidus infection in sea cucumber Apostichopus japonicus.

    PubMed

    Sun, Yongxin; Du, Xingfan; Li, Shuying; Wen, Zhixin; Li, Yajie; Li, Xuejun; Meng, Nan; Mi, Rui; Ma, Shuhui; Sun, Aijie

    2015-08-01

    Vibrio splendidus is the common pathogen that causes infectious diseases widely spread in cultured sea cucumber in China. Therefore, we investigated the ability of Cordyceps militaris to protect against infection caused by V. splendidus. In this study, sea cucumbers were fed with a diet containing 0 (control), 1%, 2% or 3% C. militaris for 28 days, and subsequently challenged with V. splendidus by injection with 1.0 × 10(9) cfu per animal. Parameters of immune response such as phagocytosis (PC), lysozyme (LSZ) activity, superoxide dismutase (SOD) activity, alkaline phosphatase (AKP) activity and acid phosphatase (ACP) activity were determined on days 0, 1, 3, 5 and 7 after injection. The results showed that dietary C. militaris at a dose of 2% or 3% significantly up-regulated (P < 0.05) all the immune parameters on day 0. One day after injection with V. splendidus, all the immune indices except ACP exhibited a tendency to decrease and then increase again, returning to the initial level on days 5 and/or 7 after injection. All the immune parameters of those fed with C. militaris were found significantly higher (P < 0.05) than those of the control group on day 1 after injection. Only LSZ activity of those fed with 1%- or 3%-C. militaris diet on day 5 showed significantly increases (P < 0.05) than the controls. As for ACP activity, the values remained steady with time, but with significant increase (P < 0.05) seen in sea cucumbers fed with 2%-C. militaris diet, and lasted for up to 7 days after V. splendidus injection. The cumulative mortality of sea cucumbers fed with the basal diet followed V. splendidus infection was significantly higher (P < 0.05) than those fed with 2% and 3% C. militaris diet. Under the experimental conditions, dietary C. militaris could enhance the immune responses of Apostichopus japonicus and improve its resistance to infection by V. splendidus. PMID:26099218

  6. Population analysis of Vibrio parahaemolyticus originating from different geographical regions demonstrates a high genetic diversity

    PubMed Central

    2014-01-01

    Background Vibrio parahaemolyticus is frequently isolated from environmental and seafood samples and associated with gastroenteritis outbreakes in American, European, Asian and African countries. To distinguish between different lineages of V. parahaemolyticus various genotyping techniques have been used, incl. multilocus sequence typing (MLST). Even though some studies have already applied MLST analysis to characterize V. parahaemolyticus strain sets, these studies have been restricted to specific geographical areas (e.g. U.S. coast, Thailand and Peru), have focused exclusively on pandemic or non-pandemic pathogenic isolates or have been based on a limited strain number. Results To generate a global picture of V. parahaemolyticus genotype distribution, a collection of 130 environmental and seafood related V. parahaemolyticus isolates of different geographical origins (Sri Lanka, Ecuador, North Sea and Baltic Sea as well as German retail) was subjected to MLST analysis after modification of gyrB and recA PCRs. The V. parahaemolyticus population was composed of 82 unique Sequence Types (STs), of which 68 (82.9%) were new to the pubMLST database. After translating the in-frame nucleotide sequences into amino acid sequences, less diversity was detectable: a total of 31 different peptide Sequence Types (pSTs) with 19 (61.3%) new pSTs were generated from the analyzed isolates. Most STs did not show a global dissemination, but some were supra-regionally distributed and clusters of STs were dependent on geographical origin. On peptide level no general clustering of strains from specific geographical regions was observed, thereby the most common pSTs were found on all continents (Asia, South America and Europe) and rare pSTs were restricted to distinct countries or even geographical regions. One lineage of pSTs associated only with strains from North and Baltic Sea strains was identified. Conclusions Our study reveals a high genetic diversity in the analyzed V. parahaemolyticus strain set as well as for geographical strain subsets, with a high proportion of newly discovered alleles and STs. Differences between the subsets were identified. Our data support the postulated population structure of V. parahaemolyticus which follows the ‘epidemic’ model of clonal expansion. Application of peptide based AA-MLST allowed the identification of reliable relationships between strains. PMID:24606756

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

    NASA Astrophysics Data System (ADS)

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

    2002-12-01

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

  8. Growth of Vibrio anguillarum in Salmon Intestinal Mucus

    PubMed Central

    Garcia, T.; Otto, K.; Kjelleberg, S.; Nelson, D. R.

    1997-01-01

    The physiological changes of Vibrio anguillarum in response to growth in salmon intestinal mucus were investigated. Growth, survival, and changes in protein expression during growth in media supplemented with mucus were compared to growth and starvation in the identical media without mucus. V. anguillarum exhibited a rapid decline in CFU following growth in mucus as the sole carbon source. No such decline was observed in Luria broth with a 2% NaCl concentration, in glucose-minimal broth (3M), or during starvation in a carbon-, nitrogen-, and phosphorus-free salt solution (NSS). The changes in protein expression during growth in mucus were examined by labeling cells with [(sup35)S]methionine and analyzing the labeled proteins by one- and two-dimensional gel electrophoresis and autoradiography. Comparison of [(sup35)S]methionine-labeled proteins from mucus-grown cells with 3M-grown cells and NSS-starved cells revealed four de novo mucus-inducible proteins (Mips). These Mips were localized in the membrane fraction of V. anguillarum. Additionally, at least one other membrane protein was found to have increased expression in response to growth in mucus. PMID:16535537

  9. The Vibrio cholerae type VI secretion system displays antimicrobial properties

    PubMed Central

    MacIntyre, Dana L.; Miyata, Sarah T.; Kitaoka, Maya; Pukatzki, Stefan

    2010-01-01

    The acute diarrheal disease cholera is caused by the marine bacterium Vibrio cholerae. A type VI secretion system (T6SS), which is structurally similar to the bacteriophage cell-puncturing device, has been recently identified in V. cholerae and is used by this organism to confer virulence toward phagocytic eukaryotes, such as J774 murine macrophages and Dictyostelium discoideum. We tested the interbacterial virulence of V. cholerae strain V52, an O37 serogroup with a constitutively active T6SS. V52 was found to be highly virulent toward multiple Gram-negative bacteria, including Escherichia coli and Salmonella Typhimurium, and caused up to a 100,000-fold reduction in E. coli survival. Because the T6SS-deficient mutants V52?vasK and V52?vasH showed toxicity defects that could be complemented, virulence displayed by V. cholerae depends on a functional T6SS. V. cholerae V52 and strains of the O1 serogroup were resistant to V52, suggesting that V. cholerae has acquired immunity independently of its serogroup. We hypothesize that the T6SS, in addition to targeting eukaryotic host cells, confers toxicity toward other bacteria, providing a means of interspecies competition to enhance environmental survival. Thus, the V. cholerae T6SS may enhance the survival of V. cholerae in its aquatic ecosystem during the transmission of cholera and between epidemics. PMID:20974937

  10. Cyclo(valine-valine) inhibits Vibrio cholerae virulence gene expression.

    PubMed

    Vikram, Amit; Ante, Vanessa M; Bina, X Renee; Zhu, Qin; Liu, Xinyu; Bina, James E

    2014-06-01

    Vibrio cholerae has been shown to produce a cyclic dipeptide, cyclo(phenylalanine-proline) (cFP), that functions to repress virulence factor production. The objective of this study was to determine if heterologous cyclic dipeptides could repress V. cholerae virulence factor production. To that end, three synthetic cyclic dipeptides that differed in their side chains from cFP were assayed for virulence inhibitory activity in V. cholerae. The results revealed that cyclo(valine-valine) (cVV) inhibited virulence factor production by a ToxR-dependent process that resulted in the repression of the virulence regulator aphA. cVV-dependent repression of aphA was found to be independent of known aphA regulatory genes. The results demonstrated that V. cholerae was able to respond to exogenous cyclic dipeptides and implicated the hydrophobic amino acid side chains on both arms of the cyclo dipeptide scaffold as structural requirements for inhibitory activity. The results further suggest that cyclic dipeptides have potential as therapeutics for cholera treatment. PMID:24644247

  11. Cyclo(valine–valine) inhibits Vibrio cholerae virulence gene expression

    PubMed Central

    Vikram, Amit; Ante, Vanessa M.; Bina, X. Renee; Zhu, Qin; Liu, Xinyu

    2014-01-01

    Vibrio cholerae has been shown to produce a cyclic dipeptide, cyclo(phenylalanine–proline) (cFP), that functions to repress virulence factor production. The objective of this study was to determine if heterologous cyclic dipeptides could repress V. cholerae virulence factor production. To that end, three synthetic cyclic dipeptides that differed in their side chains from cFP were assayed for virulence inhibitory activity in V. cholerae. The results revealed that cyclo(valine–valine) (cVV) inhibited virulence factor production by a ToxR-dependent process that resulted in the repression of the virulence regulator aphA. cVV-dependent repression of aphA was found to be independent of known aphA regulatory genes. The results demonstrated that V. cholerae was able to respond to exogenous cyclic dipeptides and implicated the hydrophobic amino acid side chains on both arms of the cyclo dipeptide scaffold as structural requirements for inhibitory activity. The results further suggest that cyclic dipeptides have potential as therapeutics for cholera treatment. PMID:24644247

  12. Stepwise changes in viable but nonculturable Vibrio cholerae cells.

    PubMed

    Imamura, Daisuke; Mizuno, Tamaki; Miyoshi, Shin-Ichi; Shinoda, Sumio

    2015-05-01

    Many bacterial species are known to become viable but nonculturable (VBNC) under conditions that are unsuitable for growth. In this study, the requirements for resuscitation of VBNC-state Vibrio cholerae cells were found to change over time. Although VBNC cells could initially be converted to culturable by treatment with catalase or HT-29 cell extract, they subsequently entered a state that was not convertible to culturable by these factors. However, fluorescence microscopy revealed the presence of live cells in this state, from which VBNC cells were resuscitated by co-cultivation with HT-29 human colon adenocarcinoma cells. Ultimately, all cells entered a state from which they could not be resuscitated, even by co-cultivation with HT-29. These characteristic changes in VBNC-state cells were a common feature of strains in both V. cholerae O1 and O139 serogroups. Thus, the VBNC state of V. cholerae is not a single property but continues to change over time. PMID:25664673

  13. Demonstration of invasiveness of Vibrio parahaemolyticus in adult rabbits by immunofluorescence.

    PubMed Central

    Boutin, B K; Townsend, S F; Scarpino, P V; Twedt, R M

    1979-01-01

    To determine possible pathogenesis of Vibrio parahaemolyticus-host-organ system interactions, studies of invasiveness were made by a direct fluorescent-antibody method. Broth cultures of live cells isolated from seafish or symptomatic humans were inoculated separately into ligated ileal loops of young New Zealand white rabbits. After suitable incubation, rabbits were sacrificed, and ileal loops and tissue specimens were aseptically removed. Ileal loops were prepared and stained with specific fluorescein-tagged antibody, and organ specimens were cultured for isolation of the inoculated Vibrio strain. All strains tested penetrated into the lamina propria of the ileum and were isolated from the cultured tissue specimens, indicating that the organism is capable of more than a superficial colonization of the gut. The presence of Vibrio in cultured tissue specimens suggests invasion of deeper tissue by either the lymphatic or the circulatory system. Images PMID:378131

  14. The use of a modified Dakin's solution (sodium hypochlorite) in the treatment of Vibrio vulnificus infection.

    PubMed

    Milner, S M; Heggers, J P

    1999-01-01

    We report the first clinical use of a modified Dakin's solution (0.025% sodium hypochlorite [NaOCl]) to halt the progress of severe cutaneous Vibrio vulnificus infection in a critically ill patient. The regimen used arose from an initial in vitro study designed to examine the sensitivity of Vibrio species to topical antimicrobial agents. Twenty-eight wound isolates were tested against the following eight topical preparations: silver sulfadiazine (Silvadene), nitrofurazone, mupirocin ointment (Bactroban), polymyxin B/bacitracin, mafenide acetate (Sulfamylon), nystatin/Silvadene, nystatin/polymyxin B/bacitracin, and 0.025% NaOCl solution. The results showed that V vulnificus, along with the other 18 Vibrio species tested, was most sensitive to the modified NaOCl solution. PMID:10347673

  15. Insect Vectors of Human Pathogens

    NSDL National Science Digital Library

    0000-00-00

    Four orders of insects (Hemiptera, Phthiraptera, Diptera, and Siphonaptera) are covered detailing vector species along with their pathogens of human importance. Links to pathogens as well as vectors are highlighted (some of these are CDC, and WHO).

  16. WATERBORNE PATHOGENS IN URBAN WATERSHEDS

    EPA Science Inventory

    Pathogens are microorganisms that can cause sickness or even death. A serious concern for managers of water resources, pathogens in the urban environment easily enter waters through a number of pathways, including discharge of inadequately treated sewage, stormwater runoff, combi...

  17. Multiplex detection of agricultural pathogens

    DOEpatents

    Siezak, Thomas R.; Gardner, Shea; Torres, Clinton; Vitalis, Elizabeth; Lenhoff, Raymond J.

    2013-01-15

    Described are kits and methods useful for detection of agricultural pathogens in a sample. Genomic sequence information from agricultural pathogens was analyzed to identify signature sequences, e.g., polynucleotide sequences useful for confirming the presence or absence of a pathogen in a sample. Primer and probe sets were designed and optimized for use in a PCR based, multiplexed Luminex assay and/or an array assay to successfully identify the presence or absence of pathogens in a sample.

  18. Multiplex detection of agricultural pathogens

    DOEpatents

    McBride, Mary Teresa (Brentwood, CA); Slezak, Thomas Richard (Livermore, CA); Messenger, Sharon Lee (Kensington, CA)

    2010-09-14

    Described are kits and methods useful for detection of seven agricultural pathogens (BPSV; BHV; BVD; FMDV; BTV; SVD; and VESV) in a sample. Genomic sequence information from 7 agricultural pathogens was analyzed to identify signature sequences, e.g., polynucleotide sequences useful for confirming the presence or absence of a pathogen in a sample. Primer and probe sets were designed and optimized for use in a PCR based, multiplexed Luminex assay to successfully identify the presence or absence of pathogens in a sample.

  19. N2-fixing vibrios isolated from the gastrointestinal tract of sea urchins.

    PubMed

    Guerinot, M L; Patriquin, D G

    1981-03-01

    Facultatively anaerobic bacteria, capable of fixing N2 anaerobically or at low O2 concentrations, were isolated from the gastrointestinal tracts of temperate (Strongylocentrotus droebachiensis) and tropical (Tripneustes ventricosus) sea urchins. Morphological and biochemical characteristics, as well as the guanine plus cytosine content of their DNA (45.9 and 48.4 mol%), place these isolates in the genus Vibrio Pacini 1865 in the family Vibrionaceae. Members of this family have not previously been shown to fix N2. These isolates are not identical to any described species in the Vibrio genus and can be distinguished by a combination of biochemical and physiological traits. PMID:6940646

  20. Vibrio mexicanus sp. nov., isolated from a cultured oyster Crassostrea corteziensis.

    PubMed

    González-Castillo, Adrián; Enciso-Ibarrra, Julissa; Bolán-Mejia, M Carmen; Balboa, Sabela; Lasa, Aide; Romalde, Jesús L; Cabanillas-Beltrán, Hector; Gomez-Gil, Bruno

    2015-08-01

    A bacterial strain was taxonomically characterised by means of a genomic approach comprising 16S rRNA gene sequence analysis, multilocus sequence analysis (MLSA), the DNA G+C content, whole genome analyses (ANI and GGDC) and phenotypic characterisation. The strain CAIM 1540(T) was isolated from a cultured oyster Crassostrea corteziensis in La Cruz, Sinaloa state, México. The isolate was found to be catalase and oxidase positive, cells were observed to be motile, O/129-sensitive and facultatively anaerobic. The almost-complete 16S rRNA gene sequence placed this strain within the genus Vibrio; the closest related species were found to be Vibrio aestivus, Vibrio marisflavi, Vibrio maritimus and Vibrio variabilis with similarity values of 99.02, 97.05, 96.70, and 96.59 % respectively. MLSA of four housekeeping genes (ftsZ, gapA, recA, and topA) was performed with the closely related species. A draft genome sequence of strain CAIM 1540(T) was obtained. The DNA G+C content of this strain was determined to be 43.7 mol%.The ANI values with V. aestivus were 89.6 % (ANIb), 90.6 % (ANIm) and a GGDC value of 39.5 ± 2.5 % was obtained; with V. marisflavi the genomic similarities were 71.5 % (ANIb), 85.5 % (ANIm) and 20.2 ± 2.3 % (GGDC); with V. maritimus 72.6 % (ANIb), 85.7 % (ANIm) and 22.0 ± 2.0 % (GGDC); and with V. variabilis 72.6 % (ANIb), 85.8 % (ANIm) and 21.6 ± 1.6 % (GGDC). These ANI and GGDC values are below the threshold for the delimitation of prokaryotic species, i.e. 95-96 and 70 %, respectively. Phenotypic characters also showed differences with the closest related species analysed. The results presented here support the description of a novel species, for which the name Vibrio mexicanus sp. nov. is proposed, with strain CAIM 1540(T) (= CECT 8828(T), = DSM 100338(T)) as the type strain. In addition, we found that the recently described species Vibrio thalassae and Vibrio madracius might be a single species because the values of ANIb 95.8 %, ANIm 96.6 % and GGDC 70.2 ± 2.9 % are above the accepted species thresholds. PMID:26021481