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1

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

PubMed

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

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

2012-12-01

2

Draft Genome Sequence of the Fish Pathogen Vibrio harveyi Strain ZJ0603  

PubMed Central

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

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

2012-01-01

3

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

PubMed

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

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

2010-01-25

4

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

Microsoft Academic Search

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

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

2000-01-01

5

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

E-print Network

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, ...

Rattanama, Pimonsri

6

Simulated hatchery system to assess bacteriophage efficacy against Vibrio harveyi.  

PubMed

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

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

2014-12-01

7

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

PubMed Central

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

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

2015-01-01

8

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

PubMed Central

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

Henke, Jennifer M.; Bassler, Bonnie L.

2004-01-01

9

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

PubMed Central

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

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

2010-01-01

10

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

Microsoft Academic Search

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

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

2011-01-01

11

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

PubMed

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

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

2013-10-01

12

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

PubMed Central

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

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

2014-01-01

13

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

PubMed

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

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

2014-10-01

14

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

Microsoft Academic Search

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

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

1997-01-01

15

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

Microsoft Academic Search

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

CHUNG-PING SHAO; LIEN-I HOR

2001-01-01

16

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

PubMed Central

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

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

2014-01-01

17

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

PubMed Central

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

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

2007-01-01

18

Biosynthesis of myristic acid in luminescent bacteria. [Vibrio harveyi  

SciTech Connect

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

Byers, D.M.

1987-05-01

19

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

PubMed

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

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

2015-01-01

20

Immunoprotective analysis of VhhP2, a Vibrio harveyi vaccine candidate.  

PubMed

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

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

2009-05-11

21

Tryptophan biosynthesis in the marine luminous bacterium Vibrio harveyi.  

PubMed Central

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

Bieger, C D; Crawford, I P

1983-01-01

22

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

Microsoft Academic Search

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

M. O. Saeed

1995-01-01

23

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

SciTech Connect

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

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

2000-02-01

24

Unexpected photoreactivation of Vibrio harveyi bacteria living in ionization environment  

SciTech Connect

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

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

2011-05-15

25

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

Microsoft Academic Search

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

Jennifer M. Henke; Bonnie L. Bassler

2004-01-01

26

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

PubMed

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

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

2015-03-27

27

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

Microsoft Academic Search

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

Wipa Suginta; Supansa Pantoom; Heino Prinz

2009-01-01

28

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

Microsoft Academic Search

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

Kawin Punyokun; Ratchanee Hongprayoon; Prapansak Srisapoome; Theerapol Sirinarumitr

2012-01-01

29

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

PubMed Central

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

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

2013-01-01

30

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

PubMed Central

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

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

2011-01-01

31

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

PubMed

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

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

2012-08-17

32

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

Microsoft Academic Search

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

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

2001-01-01

33

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

Microsoft Academic Search

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

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

2004-01-01

34

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

PubMed

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

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

2013-03-26

35

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

PubMed

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

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

2013-10-01

36

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

PubMed

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

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

2013-12-01

37

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

PubMed Central

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

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

2000-01-01

38

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

PubMed Central

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

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

2014-01-01

39

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

PubMed Central

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

Urbanczyk, Henryk; Ogura, Yoshitoshi; Hayashi, Tetsuya

2015-01-01

40

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

Microsoft Academic Search

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

S. K. Patra; K. S. Mohamed

2003-01-01

41

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

Microsoft Academic Search

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

Sumio Shinoda

42

Pathogenicity of vibrios in fish: An overview  

NASA Astrophysics Data System (ADS)

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

Jun, Li; Woo, Norman Y. S.

2003-10-01

43

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

Microsoft Academic Search

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

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

2010-01-01

44

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

PubMed

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

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

2014-11-01

45

Genomics of Pathogenic Vibrio Species  

NASA Astrophysics Data System (ADS)

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

Dziejman, Michelle; Yildiz, Fitnat H.

46

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

PubMed Central

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

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

2012-01-01

47

Vibrio fluvialis: an emerging human pathogen  

PubMed Central

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

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

2014-01-01

48

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

PubMed

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

Pholdaeng, Komsil; Pongsamart, Sunanta

2010-04-01

49

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

PubMed Central

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

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

2008-01-01

50

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

PubMed

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

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

2009-07-01

51

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

PubMed

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

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

2015-01-01

52

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

PubMed Central

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

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

2015-01-01

53

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

PubMed

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

González-Flecha, B; Demple, B

1994-04-01

54

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

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

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

2013-01-01

55

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

PubMed

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

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

2014-10-01

56

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

57

ISOLATION AND DESCRIPTION OF TWO VIBRIOS PATHOGENIC TO PACIFIC  

E-print Network

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

58

Phylogeny of the coral pathogen Vibrio coralliilyticus.  

PubMed

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

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

2010-02-01

59

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

PubMed Central

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

Hundenborn, Jörg; Thurig, Steffi

2013-01-01

60

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

PubMed Central

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

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

1997-01-01

61

Ecological study of pathogenic vibrios in aquatic environments.  

PubMed

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

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

2013-01-01

62

Vibriophages and Their Interactions with the Fish Pathogen Vibrio anguillarum  

PubMed Central

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

Tan, Demeng; Gram, Lone

2014-01-01

63

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

NASA Astrophysics Data System (ADS)

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

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

2014-09-01

64

Temperature regulation of virulence factors in the pathogen Vibrio coralliilyticus  

PubMed Central

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

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

2012-01-01

65

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

PubMed

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

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

2015-01-01

66

Abstract The recent discovery that the fish pathogen Vibrio salmonicida is closely related to the luminous  

E-print Network

Abstract The recent discovery that the fish pathogen Vibrio salmonicida is closely related salmon (Salmo salar), rainbow trout (Oncorhynchus mykiss), and cod (Gadus morhua) (Egidius 1986; Wiik et luminescence in the cold-water fish pathogen Vibrio salmonicida Arch Microbiol (1999) 171:205­209 © Springer

McFall-Ngai, Margaret

67

Phage therapy treatment of the coral pathogen Vibrio coralliilyticus  

PubMed Central

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

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

2013-01-01

68

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

Microsoft Academic Search

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

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

1994-01-01

69

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

PubMed

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

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

2013-12-01

70

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

PubMed

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

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

2015-04-01

71

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

PubMed

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

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

2014-12-01

72

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

E-print Network

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

Paris-Sud XI, Université de

73

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

PubMed

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

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

2014-02-01

74

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

ScienceCinema

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

Colwell, Rita [University of Maryland

2013-02-12

75

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

SciTech Connect

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

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

2012-06-01

76

Impact of milk fish farming in the tropics on potentially pathogenic vibrios.  

PubMed

Ratios of sucrose-negative to sucrose-positive vibrios on TCBS agar (suc-/suc+) indicate the abundance of potential human pathogenic non-cholera vibrios in coastal mariculture environments of the Lingayen Gulf (Philippines. In guts of adult maricultured milkfish (Chanos chanos) of suc- vibrios reached extreme peak values ranging between 2 and 545 million per g wet weight. Suc- vibrios outnumbered suc+ vibrios in anoxic sediments, too, and were rarely predominant in coastal waters or in oxidized sediments. Suc-/suc+ ratios in sediments increased toward the mariculture areas with distance from the open sea at decreasing redox potentials. There is circumstantial evidence that suc- vibrios can be dispersed from mariculture areas to adjacent environments including coral reefs. An immediate human health risk by pathogenic Vibrio species is discounted, since milkfish guts contained mainly members of the Enterovibrio group. A representative isolate of these contained proteolytic and other virulence factors, but no genes encoding toxins characteristic of clinical Vibrio species. PMID:24079922

Reichardt, W T; Reyes, J M; Pueblos, M J; Lluisma, A O

2013-12-15

77

Power plays: iron transport and energy transduction in pathogenic vibrios  

Microsoft Academic Search

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

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

2011-01-01

78

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

PubMed

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

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

2014-01-01

79

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

PubMed Central

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

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

2014-01-01

80

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

PubMed Central

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

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

2014-01-01

81

Challenge of New Zealand Greenshell mussel Perna canaliculus larvae using two Vibrio pathogens: a hatchery study.  

PubMed

Bacterial diseases remain a large problem in aquaculture hatcheries. The successful design and implementation of protective measures in the hatchery depends on an understanding of the dynamics of the infection process. Developing an in situ experimental protocol for pathogen challenge is therefore of paramount importance. Here, we demonstrated the minimum effective pathogenic dose (MEPD) of Vibrio splendidus (10(5) CFU ml(-1)) and a Vibrio coralliilyticus/neptunius-like isolate, Vibrio sp. DO1 (10(6) CFU ml(-1)), for New Zealand Greenshell mussel (GSM, Perna canaliculus) larvae during hatchery production. In a flow-through water hatchery system, larvae given 1 to 2 h of static water exposure to these pathogen doses showed respective average cumulative mortalities of 58 and 69% on the fourth day following pathogen exposure. After the 1 to 2 h static exposure, larvae were returned to flow-through water. Larvae exposed to a dosage one order of magnitude greater than the MEPD had higher mortalities of 73 and 96% for V. splendidus and Vibrio sp. DO1 respectively. These 4 levels of mortality were significantly greater than those of the non-exposed control larvae which respectively averaged 23 and 35% in experiments involving V. splendidus and Vibrio sp. DO1. Experiments were repeated 4 times to confirm reproducibility. After pathogen exposure, pathogens were detected in the larvae and tank water of treatments with dosages of > or =10(5) CFU ml(-1) (V. splendidus) and 10(6) CFU ml(-1) (Vibrio sp. DO1), but not in treatments with lower pathogen dosages. The challenge protocols are reproducible and provide an opportunity to assess measures for the protection of GSM larvae against infection in the hatchery environment. PMID:19899345

Kesarcodi-Watson, Aditya; Kaspar, Heinrich; Lategan, M Josie; Gibson, Lewis F

2009-09-01

82

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

PubMed Central

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

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

1999-01-01

83

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

PubMed

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

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

1999-06-01

84

Relationships between Environmental Factors and Pathogenic Vibrios in the Northern Gulf of Mexico ? †  

PubMed Central

Although autochthonous vibrio densities are known to be influenced by water temperature and salinity, little is understood about other environmental factors associated with their abundance and distribution. Densities of culturable Vibrio vulnificus containing vvh (V. vulnificus hemolysin gene) and V. parahaemolyticus containing tlh (thermolabile hemolysin gene, ubiquitous in V. parahaemolyticus), tdh (thermostable direct hemolysin gene, V. parahaemolyticus pathogenicity factor), and trh (tdh-related hemolysin gene, V. parahaemolyticus pathogenicity factor) were measured in coastal waters of Mississippi and Alabama. Over a 19-month sampling period, vibrio densities in water, oysters, and sediment varied significantly with sea surface temperature (SST). On average, tdh-to-tlh ratios were significantly higher than trh-to-tlh ratios in water and oysters but not in sediment. Although tlh densities were lower than vvh densities in water and in oysters, the opposite was true in sediment. Regression analysis indicated that SST had a significant association with vvh and tlh densities in water and oysters, while salinity was significantly related to vibrio densities in the water column. Chlorophyll a levels in the water were correlated significantly with vvh in sediment and oysters and with pathogenic V. parahaemolyticus (tdh and trh) in the water column. Furthermore, turbidity was a significant predictor of V. parahaemolyticus density in all sample types (water, oyster, and sediment), and its role in predicting the risk of V. parahaemolyticus illness may be more important than previously realized. This study identified (i) culturable vibrios in winter sediment samples, (ii) niche-based differences in the abundance of vibrios, and (iii) predictive signatures resulting from correlations between environmental parameters and vibrio densities. PMID:20817802

Johnson, C. N.; Flowers, A. R.; Noriea, N. F.; Zimmerman, A. M.; Bowers, J. C.; DePaola, A.; Grimes, D. J.

2010-01-01

85

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

E-print Network

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

Dunn, Anne K.

86

Ocean warming and spread of pathogenic vibrios in the aquatic environment.  

PubMed

Vibrios are among the most common bacteria that inhabit surface waters throughout the world and are responsible for a number of severe infections both in humans and animals. Several reports recently showed that human Vibrio illnesses are increasing worldwide including fatal acute diarrheal diseases, such as cholera, gastroenteritis, wound infections, and septicemia. Many scientists believe this increase may be associated with global warming and rise in sea surface temperature (SST), although not enough evidence is available to support a causal link between emergence of Vibrio infections and climate warming. The effect of increased SST in promoting spread of vibrios in coastal and brackish waters is considered a causal factor explaining this trend. Field and laboratory studies carried out over the past 40 years supported this hypothesis, clearly showing temperature promotes Vibrio growth and persistence in the aquatic environment. Most recently, a long-term retrospective microbiological study carried out in the coastal waters of the southern North Sea provided the first experimental evidence for a positive and significant relationship between SST and Vibrio occurrence over a multidecadal time scale. As a future challenge, macroecological studies of the effects of ocean warming on Vibrio persistence and spread in the aquatic environment over large spatial and temporal scales would conclusively support evidence acquired to date combined with studies of the impact of global warming on epidemiologically relevant variables, such as host susceptibility and exposure. Assessing a causal link between ongoing climate change and enhanced growth and spread of vibrios and related illness is expected to improve forecast and mitigate future outbreaks associated with these pathogens. PMID:23280498

Vezzulli, Luigi; Colwell, Rita R; Pruzzo, Carla

2013-05-01

87

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

PubMed

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

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

2014-01-01

88

Genome-wide phylogenetic analysis of the pathogenic potential of Vibrio furnissii  

PubMed Central

We recently reported the genome sequence of a free-living strain of Vibrio furnissii (NCTC 11218) harvested from an estuarine environment. V. furnissii is a widespread, free-living proteobacterium and emerging pathogen that can cause acute gastroenteritis in humans and lethal zoonoses in aquatic invertebrates, including farmed crustaceans and molluscs. Here we present the analyses to assess the potential pathogenic impact of V. furnissii. We compared the complete genome of V. furnissii with 8 other emerging and pathogenic Vibrio species. We selected and analyzed more deeply 10 genomic regions based upon unique or common features, and used 3 of these regions to construct a phylogenetic tree. Thus, we positioned V. furnissii more accurately than before and revealed a closer relationship between V. furnissii and V. cholerae than previously thought. However, V. furnissii lacks several important features normally associated with virulence in the human pathogens V. cholera and V. vulnificus. A striking feature of the V. furnissii genome is the hugely increased Super Integron, compared to the other Vibrio. Analyses of predicted genomic islands resulted in the discovery of a protein sequence that is present only in Vibrio associated with diseases in aquatic animals. We also discovered evidence of high levels horizontal gene transfer in V. furnissii. V. furnissii seems therefore to have a dynamic and fluid genome that could quickly adapt to environmental perturbation or increase its pathogenicity. Taken together, these analyses confirm the potential of V. furnissii as an emerging marine and possible human pathogen, especially in the developing, tropical, coastal regions that are most at risk from climate change. PMID:25191313

Lux, Thomas M.; Lee, Rob; Love, John

2014-01-01

89

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

PubMed

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

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

2013-05-01

90

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

PubMed

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

Zhu, Shiwei; Kojima, Seiji; Homma, Michio

2013-01-01

91

Detection of pathogenic Vibrio spp. in shellfish by using multiplex PCR and DNA microarrays.  

PubMed

This study describes the development of a gene-specific DNA microarray coupled with multiplex PCR for the comprehensive detection of pathogenic vibrios that are natural inhabitants of warm coastal waters and shellfish. Multiplex PCR with vvh and viuB for Vibrio vulnificus, with ompU, toxR, tcpI, and hlyA for V. cholerae, and with tlh, tdh, trh, and open reading frame 8 for V. parahaemolyticus helped to ensure that total and pathogenic strains, including subtypes of the three Vibrio spp., could be detected and discriminated. For DNA microarrays, oligonucleotide probes for these targeted genes were deposited onto epoxysilane-derivatized, 12-well, Teflon-masked slides by using a MicroGrid II arrayer. Amplified PCR products were hybridized to arrays at 50 degrees C and detected by using tyramide signal amplification with Alexa Fluor 546 fluorescent dye. Slides were imaged by using an arrayWoRx scanner. The detection sensitivity for pure cultures without enrichment was 10(2) to 10(3) CFU/ml, and the specificity was 100%. However, 5 h of sample enrichment followed by DNA extraction with Instagene matrix and multiplex PCR with microarray hybridization resulted in the detection of 1 CFU in 1 g of oyster tissue homogenate. Thus, enrichment of the bacterial pathogens permitted higher sensitivity in compliance with the Interstate Shellfish Sanitation Conference guideline. Application of the DNA microarray methodology to natural oysters revealed the presence of V. vulnificus (100%) and V. parahaemolyticus (83%). However, V. cholerae was not detected in natural oysters. An assay involving a combination of multiplex PCR and DNA microarray hybridization would help to ensure rapid and accurate detection of pathogenic vibrios in shellfish, thereby improving the microbiological safety of shellfish for consumers. PMID:15574946

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

2004-12-01

92

Survival of Normal and Chlorine-Stressed Pathogenic and Non-Pathogenic Vibrio parahaemolyticus Under Adverse Conditions  

PubMed Central

Background: Vibrio parahaemolyticus is an important human pathogen which can cause gastroenteritis when consumed in raw or partially-cooked seafood. The pathogenesis of V. parahaemolyticus is based on the presence of virulence factors: the thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH), encoded by the tdh and trh genes, respectively. Objectives: The present study aimed to evaluate the survival of normal and chlorine-stressed cells of pathogenic and non-pathogenic V. parahaemolyticus under adverse conditions. Materials and Methods: Normal and chlorine-stressed cells of pathogenic and non-pathogenic V. parahaemolyticus were subjected to environmental stresses such as low storage temperature (4°C and -18°C), high incubation temperature (50°C) and high NaCl content (20%). Viable counts were then made at various time intervals by surface plating on TSA-2.0% NaCl, and the survival rates of the cells were determined and compared. Results: Findings of the current study revealed that the normal cells of pathogenic and non-pathogenic V. parahaemolyticus, as well as the chlorine-stressed cells of both strains behave similarly under adverse conditions. In addition, chlorine stress increased the susceptibility of pathogenic and non-pathogenic V. parahaemolyticus to incubation at 4°C, and the presence of high NaCl content in the medium. However, chlorine stress did not significantly affect the thermal tolerance of pathogenic and non-pathogenic V. parahaemolyticus, and the susceptibility to incubation at -18°C. Conclusions: Chlorine-stressed cells of V. parahaemolyticus were more susceptible to adverse conditions than the non-stressed ones. Pathogenic and non-pathogenic strains showed the same survival characteristics under the adverse conditions. These results should be considered in the development of food preservation measures. PMID:25147689

Zarei, Mehdi; Eskandari, Mohammad Hadi; Keshtkaran, Somayeh

2014-01-01

93

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

PubMed

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

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

2015-02-01

94

Role of heme compounds and haptoglobin in Vibrio vulnificus pathogenicity.  

PubMed Central

An induced peritonitis model was employed in mice to determine whether heme-containing molecules enhance the lethality of infections by Vibrio vulnificus. The lethality of intraperitoneal (ip) inocula of the bacteria was increased by concurrent injections (ip) of hemoglobin, methemoglobin, or hematin, but not by myoglobin. Similar results were obtained in mice with phenylhydrazine-induced hemoglobinemia, in which after ip injections of V. vulnificus, a direct correlation between lethality and levels of plasma hemoglobin was observed. In vitro studies indicated that the growth of V. vulnificus, which was limited in an iron-poor medium, was enhanced by the addition of hemoglobin in a manner similar to an inorganic iron source, ferric ammonium citrate. These results suggest that V. vulnificus is capable of extracting iron from hemoglobin for use as a nutrilite, thereby promoting growth and increased lethality in the in vivo models. Further studies with human serum cultures demonstrated that the growth of V. vulnificus was not decreased when hemoglobin added to the serum was completely complexed with haptoglobin; these results are in opposition to those with cultures of Escherichia coli. These results are discussed relative to the capacity of V. vulnificus to produce fatal human infections. PMID:6746093

Helms, S D; Oliver, J D; Travis, J C

1984-01-01

95

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

PubMed Central

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

Enger, O; Husevåg, B; Goksøyr, J

1989-01-01

96

Urea hydrolysis can predict the potential pathogenicity of Vibrio parahaemolyticus strains isolated in the Pacific Northwest.  

PubMed Central

The ability of some strains of Vibrio parahaemolyticus to hydrolyze urea (uh+) can be used as a marker to predict which strains isolated from molluscan shellfish harvested in the Pacific Northwest are potentially pathogenic. The thermostable direct hemolysin-producing (TDH+) characteristic is a marker that is correlated with potential pathogenicity, and all of the TDH+ strains that we have isolated have been found to be uh+. Most of the uh+ strains belong to somatic antigen groups O3, O4 and O5. TDH+ strains are usually members of groups O4 and O5. The strains most often associated with human illness are members of the uh+, O4 group. The test for urease production is a simple screening test that can be helpful in predicting which strains are potentially pathogenic. PMID:8085837

Kaysner, C A; Abeyta, C; Trost, P A; Wetherington, J H; Jinneman, K C; Hill, W E; Wekell, M M

1994-01-01

97

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

PubMed Central

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

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

2011-01-01

98

An Improved Detection and Quantification Method for the Coral Pathogen Vibrio coralliilyticus  

PubMed Central

DNA- and RNA-based PCR and reverse-transcription real-time PCR assays were developed for diagnostic detection of the vcpA zinc-metalloprotease implicated in the virulence of the coral pathogen Vibrio coralliilyticus. Both PCR methods were highly specific for V. coralliilyticus and failed to amplify strains of closely-related Vibrio species. The assays correctly detected all globally occurring V. coralliilyticus isolates including a newly-described isolate [TAV24] infecting gorgonians in the Mediterranean Sea and highlighted those isolates that had been potentially misidentified, in particular V. tubiashii strains ATCC 19105 and RE22, historically described as important oyster pathogens. The real-time assay is sensitive, detecting 10 gene copies and the relationships between gene copy number and cycle threshold (CT) were highly linear (R2?99.7). The real-time assay was also not affected by interference from non-target DNA. These assays are useful for rapid detection of V. coralliilyticus and monitoring of virulence levels in environmental samples, allowing for implementation of timely management steps to limit and possibly prevent losses due to V. coralliilyticus infection, as well as furthering investigations of factors affecting pathogenesis of this important marine pathogen. PMID:24339968

Wilson, Bryan; Muirhead, Andrew; Bazanella, Monika; Huete-Stauffer, Carla; Vezzulli, Luigi; Bourne, David G.

2013-01-01

99

Virulence of an emerging pathogenic lineage of Vibrio nigripulchritudo is dependent on two plasmids  

PubMed Central

Summary Vibrioses are the predominant bacterial infections in marine shrimp farms. Vibrio nigripulchritudo is an emerging pathogen of the cultured shrimp Litopenaeus stylirostris in New Caledonia and other regions in the Indo-Pacific. The molecular determinants of V. nigripulchritudo pathogenicity are unknown; however, molecular epidemiological studies have revealed that recent pathogenic V. nigripulchritudo isolates from New Caledonia all cluster into a monophyletic clade and contain a small plasmid, pB1067. Here, we report that a large plasmid, pA1066 (247 kb), can also serve as a marker for virulent V. nigripulchritudo, and that an ancestral version of this plasmid was likely acquired prior to other virulence-linked markers. Additionally, we demonstrate that pA1066 is critical for the full virulence of V. nigripulchritudo in several newly developed experimental models of infection. Plasmid pB1067 also contributes to virulence; only strains containing both plasmids induced the highest level of shrimp mortality. Thus, it appears that these plasmids, which are absent from non-pathogenic isolates, may be driving forces, as well as markers, for the emergence of a pathogenic lineage of V. nigripulchritudo. PMID:20825454

Le Roux, Frédérique; Labreuche, Yannick; Davis, Brigid M; Iqbal, Naeem; Mangenot, Sophie; Goarant, Cyrille; Mazel, Didier; Waldor, Matthew K

2011-01-01

100

Differential specificity of selective culture media for enumeration of pathogenic vibrios: Advantages and limitations of multi-plating methods.  

PubMed

Plating environmental samples on vibrio-selective chromogenic media is a commonly used technique that allows one to quickly estimate concentrations of putative vibrio pathogens or to isolate them for further study. Although this approach is convenient, its usefulness depends directly on how well the procedure selects against false positives. We tested whether a chromogenic medium, CHROMagar Vibrio (CaV), used alone (single-plating) or in combination (double-plating) with a traditional medium thiosulfate-citrate-bile-salts (TCBS), could improve the discrimination among three pathogenic vibrio species (Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus) and thereby decrease the number of false-positive colonies that must be screened by molecular methods. Assays were conducted on water samples from two estuarine environments (one subtropical, one tropical) in a variety of seasonal conditions. The results of the double-plating method were confirmed by PCR and 16S rRNA sequencing. Our data indicate that there is no significant difference in the false-positive rate between CaV and TCBS when using a single-plating technique, but determining color changes on the two media sequentially (double-plating) reduced the rate of false positive identification in most cases. The improvement achieved was about two-fold on average, but varied greatly (from 0- to 5-fold) and depended on the sampling time and location. The double-plating method was most effective for V. vulnificus in warm months, when overall V. vulnificus abundance is high (false positive rates as low as 2%, n=178). Similar results were obtained for V. cholerae (minimum false positive rate of 16%, n=146). In contrast, the false positive rate for V. parahaemolyticus was always high (minimum of 59%, n=109). Sequence analysis of false-positive isolates indicated that the majority of confounding isolates are from the Vibrionaceae family, however, members of distantly related bacterial groups were also able to grow on vibrio-selective media, even when using the double-plating method. In conclusion, the double-plating assay is a simple means to increase the efficiency of identifying pathogenic vibrios in aquatic environments and to reduce the number of molecular assays required for identity confirmation. However, the high spatial and temporal variability in the performance of the media mean that molecular approaches are still essential to obtain the most accurate vibrio abundance estimates from environmental samples. PMID:25602161

Nigro, Olivia D; Steward, Grieg F

2015-04-01

101

Taxonomy of bacterial fish pathogens  

PubMed Central

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

2011-01-01

102

Genetically divergent Symbiodinium sp. display distinct molecular responses to pathogenic Vibrio and thermal stress.  

PubMed

Global climate change and anthropogenic activities are threatening the future survival of coral reef ecosystems. The ability of reef-building zooxanthellate coral to survive these stressors may be determined through fundamental differences within their symbiotic dinoflagellates (Symbiodinium sp.). We define the in vitro apoptotic response of 2 evolutionarily distant Symbiodinium sp., subtypes B2 and C1, to determine the synergistic effects of disease and temperature on cell viability using flow cytometry. The putative yellow band disease (YBD) consortium of Vibrio spp. bacteria and temperature (33°C) had a positive synergistic effect on C1 apoptosis, while B2 displayed increased apoptosis to elevated temperature (29 and 33°C), the Vibrio consortium, and a lone virulent strain of V. alginolyticus, but no synergistic effects. Additionally, heat shock protein 60 expression revealed differential cell-mediated temperature sensitivity between subtypes via western blotting. This result marks the first evidence of Symbiodinium sp. apoptotic variations to YBD pathogens and emphasizes the potential impact of synergistic stress on globally distributed coral-Symbiodinium symbioses. PMID:25449326

Hauff, Briana; Cervino, James M; Haslun, Joshua A; Krucher, Nancy; Wier, Andrew M; Mannix, Alexandra L; Hughen, Konrad; Strychar, Kevin B

2014-12-01

103

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

PubMed

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

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

2012-12-13

104

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

PubMed

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

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

2014-04-01

105

Molecular Epidemiology and Genetic Variation of Pathogenic Vibrio parahaemolyticus in Peru  

PubMed Central

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

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

2013-01-01

106

Characterization of pathogenic vibrios isolated from bivalve hatcheries in Galicia, NW Atlantic coast of Spain. Description of Vibrio tubiashii subsp. europaensis subsp. nov.  

PubMed

The taxonomic position of the bivalve pathogen PP-638 was studied together with five similar isolates. The strains were isolated from flat oyster (Ostrea edulis) and Manila clam (Venerupis philippinarum) cultures during outbreaks of disease in two shellfish hatcheries (Galicia, NW Spain). The pathogenicity, previously established for PP-638, was demonstrated with all isolates and for several bivalve species, including the original hosts. On the basis of phenotypic characterization and 16S rRNA gene sequences, a tight group was defined within the genus Vibrio. Multilocus sequence analysis (MLSA) based on concatenated sequences of the 16S rRNA gene and the five housekeeping genes recA, rpoA, pyrH, gyrB and ftsZ revealed that these strains form a cluster within the Orientalis clade, close to the species Vibrio tubiashii. The results of MLSA, the DDH rate and the phenotypic differences with the type strain of V. tubiashii supported the differentiation of the Galician isolates as a new subspecies within V. tubiashii, for which the name V. tubiashii subsp. europaensis subsp. nov. is proposed (type strain PP-638(T)=CECT 8136(T)=DSM 7349(T)) The emended description of V. tubiashii is included. The pathogenicity assays widen the host range of V. tubiashii to add two unreported species, Venerupis decussata and Donax trunculus, and the described as relatively resistant species V. philippinarum. PMID:25555343

Prado, Susana; Dubert, Javier; Barja, Juan L

2015-02-01

107

Variability of Total and Pathogenic Vibrio parahaemolyticus Densities in Northern Gulf of Mexico Water and Oysters?  

PubMed Central

Vibrio parahaemolyticus is indigenous to coastal environments and a frequent cause of seafood-borne gastroenteritis in the United States, primarily due to raw-oyster consumption. Previous seasonal-cycle studies of V. parahaemolyticus have identified water temperature as the strongest environmental predictor. Salinity has also been identified, although it is evident that its effect on annual variation is not as pronounced. The effects of other environmental factors, both with respect to the seasonal cycle and intraseasonal variation, are uncertain. This study investigated intraseasonal variations of densities of total and pathogenic V. parahaemolyticus organisms in oysters and overlying waters during the summer of 2004 at two sites in the northern Gulf of Mexico. Regression analyses indicated significant associations (P < 0.001) between total V. parahaemolyticus densities and salinity, as well as turbidity in water and in oysters at the Mississippi site but not at the Alabama site. Pathogenic V. parahaemolyticus organisms in Mississippi oyster and water samples were detected in 56% (9 out of 16) and 78% (43 out of 55) of samples, respectively. In contrast, 44% (7 out of 16) of oyster samples and 30% (14 out of 47) of water samples from Alabama were positive. At both sites, there was greater sample-to-sample variability in pathogenic V. parahaemolyticus densities than in total V. parahaemolyticus densities. These data suggest that, although total V. parahaemolyticus densities may be very informative, there is greater uncertainty when total V. parahaemolyticus densities are used to predict the risk of infection by pathogenic V. parahaemolyticus than previously recognized. PMID:17921270

Zimmerman, A. M.; DePaola, A.; Bowers, J. C.; Krantz, J. A.; Nordstrom, J. L.; Johnson, C. N.; Grimes, D. J.

2007-01-01

108

Indigenous Vibrio cholerae strains from a non-endemic region are pathogenic  

PubMed Central

Of the 200+ serogroups of Vibrio cholerae, only O1 or O139 strains are reported to cause cholera, and mostly in endemic regions. Cholera outbreaks elsewhere are considered to be via importation of pathogenic strains. Using established animal models, we show that diverse V. cholerae strains indigenous to a non-endemic environment (Sydney, Australia), including non-O1/O139 serogroup strains, are able to both colonize the intestine and result in fluid accumulation despite lacking virulence factors believed to be important. Most strains lacked the type three secretion system considered a mediator of diarrhoea in non-O1/O13 V. cholerae. Multi-locus sequence typing (MLST) showed that the Sydney isolates did not form a single clade and were distinct from O1/O139 toxigenic strains. There was no correlation between genetic relatedness and the profile of virulence-associated factors. Current analyses of diseases mediated by V. cholerae focus on endemic regions, with only those strains that possess particular virulence factors considered pathogenic. Our data suggest that factors other than those previously well described are of potential importance in influencing disease outbreaks. PMID:23407641

Islam, Atiqul; Labbate, Maurizio; Djordjevic, Steven P.; Alam, Munirul; Darling, Aaron; Melvold, Jacqueline; Holmes, Andrew J.; Johura, Fatema T.; Cravioto, Alejandro; Charles, Ian G.; Stokes, H. W.

2013-01-01

109

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

Microsoft Academic Search

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

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

2003-01-01

110

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

PubMed Central

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

Mekalanos, John J.

2014-01-01

111

Genomic science in understanding cholera outbreaks and evolution of Vibrio cholerae as a human pathogen.  

PubMed

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

Robins, William P; Mekalanos, John J

2014-01-01

112

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

PubMed Central

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.

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

113

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

PubMed Central

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

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

2005-01-01

114

The HlyU Protein Is a Positive Regulator of rtxA1, a Gene Responsible for Cytotoxicity and Virulence in the Human Pathogen Vibrio vulnificus  

Microsoft Academic Search

Vibrio vulnificus is an opportunistic human pathogen that preferentially infects compromised iron- overloaded patients, causing a fatal primary septicemia with very rapid progress, resulting in a high mortality rate. In this study we determined that the HlyU protein, a virulence factor in V. vulnificus CMCP6, up-regulates the expression of VV20479, a homologue of the Vibrio cholerae RTX (repeats in toxin)

Moqing Liu; Alejandro F. Alice; Hiroaki Naka; Jorge H. Crosa

2007-01-01

115

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

PubMed Central

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

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

2010-01-01

116

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

PubMed Central

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

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

2011-01-01

117

Temporal and spatial variability in culturable pathogenic Vibrio spp. in Lake Pontchartrain, Louisiana, following hurricanes Katrina and Rita.  

PubMed

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

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

2011-08-01

118

Antibiofilm activity of Dendrophthoe falcata against different bacterial pathogens.  

PubMed

Dendrophthoe falcata is a hemiparasitic plant commonly used for ailments such as ulcers, asthma, impotence, paralysis, skin diseases, menstrual troubles, pulmonary tuberculosis, and wounds. In this context, the validations of the traditional claim that the leaf extract of D. falcata possesses antibiofilm and anti-quorum sensing activity against different bacterial pathogens were assessed. The bacterial biofilms were quantified by crystal violet staining. Among the 17 bacterial pathogens screened, the methanolic fraction of the leaf extract clearly demonstrated antibiofilm activity for Proteus mirabilis, Vibrio vulnificus, Aeromonas hydrophila, Shigella sonnei, Chromobacterium violaceum ATCC 12472, Vibrio parahaemolyticus, Vibrio harveyi, Vibrio alginolyticus, Vibrio cholerae, and Proteus vulgaris. At biofilm inhibitory concentrations, biofilm formation was reduced by up to 70-90?%. Furthermore, the potential quorum-sensing activity of the leaf extract was tested by agar well diffusion using Chromobacterium violaceum (ATCC 12472 & CV O26) reporter strains. The inhibition of violacein production may be due to direct or indirect interference on QS by active constituents or the interactive effect of different phytocompounds present in the extracts. This is the first report on antibiofilm and QS activity of D. falcata leaf extracts, signifying the scope for development of complementary medicine for biofilm-associated infections. PMID:23115018

Karthikeyan, Alagarsamy; Rameshkumar, Ramakrishnan; Sivakumar, Nallusamy; Al Amri, Issa S; Karutha Pandian, Shunmugiah; Ramesh, Manikandan

2012-12-01

119

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

PubMed Central

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

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

2012-01-01

120

Population Genetics of Vibrio vulnificus: Identification of Two Divisions and a Distinct Eel-Pathogenic Clone  

Microsoft Academic Search

Genetic relationships among 62 Vibrio vulnificus strains of different geographical and host origins were analyzed by multilocus enzyme electrophoresis (MLEE), random amplification of polymorphic DNA (RAPD), and sequence analyses of the recA and glnA genes. Out of 15 genetic loci analyzed by MLEE, 11 were polymorphic. Cluster analysis identified 43 distinct electrophoretic types (ETs) separating the V. vulnificus population into

Michaela Gutacker; Nadine Conza; Cinzia Benagli; Ambra Pedroli; Marco Valerio Bernasconi; Lise Permin; Rosa Aznar; Jean-Claude Piffaretti

2003-01-01

121

Use of OmpU porins for attachment and invasion of Crassostrea gigas immune cells by the oyster pathogen Vibrio splendidus.  

PubMed

OmpU porins are increasingly recognized as key determinants of pathogenic host Vibrio interactions. Although mechanisms remain incompletely understood, various species, including the human pathogen Vibrio cholera, require OmpU for host colonization and virulence. We have shown previously that OmpU is essential for virulence in the oyster pathogen Vibrio splendidus LGP32. Here, we showed that V. splendidus LGP32 invades the oyster immune cells, the hemocytes, through subversion of host-cell actin cytoskeleton. In this process, OmpU serves as an adhesin/invasin required for ?-integrin recognition and host cell invasion. Furthermore, the major protein of oyster plasma, the extracellular superoxide dismutase Cg-EcSOD, is used as an opsonin mediating the OmpU-promoted phagocytosis through its RGD sequence. Finally, the endocytosed bacteria were found to survive intracellularly, evading the host defense by preventing acidic vacuole formation and limiting reactive oxygen species production. We conclude that (i) V. splendidus is a facultative intracellular pathogen that manipulates host defense mechanisms to enter and survive in host immune cells, and (ii) that OmpU is a major determinant of host cell invasion in Vibrio species, used by V. splendidus LGP32 to attach and invade oyster hemocytes through opsonisation by the oyster plasma Cg-EcSOD. PMID:21282662

Duperthuy, Marylise; Schmitt, Paulina; Garzón, Edwin; Caro, Audrey; Rosa, Rafael D; Le Roux, Frédérique; Lautrédou-Audouy, Nicole; Got, Patrice; Romestand, Bernard; de Lorgeril, Julien; Kieffer-Jaquinod, Sylvie; Bachère, Evelyne; Destoumieux-Garzón, Delphine

2011-02-15

122

Is Vibrio fluvialis emerging as a pathogen with epidemic potential in coastal region of eastern India following cyclone Aila?  

PubMed

An isolated area with diarrhoea epidemic was explored at Pakhirala village of the Sundarbans, a coastal region of South 24 Parganas district of West Bengal, eastern India. The Pakhirala village was surrounded by other villages affected by a similar epidemic. The affected villages experienced this epidemic following the cyclone Aila, which had hit the coastal region of the Sundarbans in eastern India. In Pakhirala, the situation was the worst. Within a span of six weeks (5 June-20 July 2009), 3,529 (91.2%) of 3,871 residents were affected by watery diarrhoea. Of all the cases (n = 3,529), 918 (26%) were affected by moderate to severe diarrhoea. In other villages, 28,550 (70%) of the 40,786 people were affected; of them, 3,997 (14%) had moderate to severe watery diarrhoea. The attack rate and the severity of the cases were significantly higher in Pakhirala village compared to other affected villages. The laboratory results revealed that Vibrio fluvialis was the predominant pathogen in Pakhirala village (5 of 6 laboratory-confirmed organisms) whereas Vibrio cholerae O1 Ogawa was the predominant pathogen in other villages of Gosaba block (7 of 9 bacteriologically-confirmed organisms). This result indicates that V fluvialis behaves more aggressively than V cholerae O1 in an epidemic situation with a higher attack rate and a different clinical picture. An in-depth study is required to explore its pathogenicity in detail, geographical distribution, and possible control measures, including development of specific vaccine preparation and determination of its efficacy. PMID:20824973

Bhattacharjee, Subhajit; Bhattacharjee, Sayantani; Bal, Baishali; Pal, Reshmi; Niyogi, Swapan Kumar; Sarkar, Kamalesh

2010-08-01

123

Is Vibrio fluvialis Emerging As a Pathogen with Epidemic Potential in Coastal Region of Eastern India Following Cyclone Aila?  

PubMed Central

An isolated area with diarrhoea epidemic was explored at Pakhirala village of the Sundarbans, a coastal region of South 24 Parganas district of West Bengal, eastern India. The Pakhirala village was surrounded by other villages affected by a similar epidemic. The affected villages experienced this epidemic following the cyclone Aila, which had hit the coastal region of the Sundarbans in eastern India. In Pakhirala, the situation was the worst. Within a span of six weeks (5 June–20 July 2009), 3,529 (91.2%) of 3,871 residents were affected by watery diarrhoea. Of all the cases (n=3,529), 918 (26%) were affected by moderate to severe diarrhoea. In other villages, 28,550 (70%) of the 40,786 people were affected; of them, 3,997 (14%) had moderate to severe watery diarrhoea. The attack rate and the severity of the cases were significantly higher in Pakhirala village compared to other affected villages. The laboratory results revealed that Vibrio fluvialis was the predominant pathogen in Pakhirala village (5 of 6 laboratory-confirmed organisms) whereas Vibrio cholerae O1 Ogawa was the predominant pathogen in other villages of Gosaba block (7 of 9 bacteriologically-confirmed organisms). This result indicates that V. fluvialis behaves more aggressively than V. cholerae O1 in an epidemic situation with a higher attack rate and a different clinical picture. An in-depth study is required to explore its pathogenicity in detail, geographical distribution, and possible control measures, including development of specific vaccine preparation and determination of its efficacy. PMID:20824973

Bhattacharjee, Subhajit; Bhattacharjee, Sayantani; Bal, Baishali; Pal, Reshmi; Niyogi, Swapan Kumar

2010-01-01

124

Selected Bacterial Strains Protect Artemia spp. from the Pathogenic Effects of Vibrio proteolyticus CW8T2  

PubMed Central

In this study Vibrio proteolyticus CW8T2 has been identified as a virulent pathogen for Artemia spp. Its infection route has been visualized with transmission electron microscopy. The pathogen affected microvilli and gut epithelial cells, disrupted epithelial cell junctions, and reached the body cavity, where it devastated cells and tissues. In vivo antagonism tests showed that preemptive colonization of the culture water with nine selected bacterial strains protected Artemia juveniles against the pathogenic effects. Two categories of the selected strains could be distinguished: (i) strains providing total protection, as no mortality occurred 2 days after the experimental infection with V. proteolyticus CW8T2, with strain LVS8 as a representative, and (ii) strains providing partial protection, as significant but not total mortality was observed, with strain LVS2 as a representative. The growth of V. proteolyticus CW8T2 in the culture medium was slowed down in the presence of strains LVS2 and LVS8, but growth suppression was distinctly higher with LVS8 than with LVS2. It was striking that the strains that gave only partial protection against the pathogen in the in vivo antagonism test showed also a restricted capability to colonize the Artemia compared to the strains providing total protection. The in vivo antagonism tests and the filtrate experiments showed that probably no extracellular bacterial compounds were involved in the protective action but that the living cells were required to protect Artemia against V. proteolyticus CW8T2. PMID:10698783

Verschuere, Laurent; Heang, Hanglamong; Criel, Godelieve; Sorgeloos, Patrick; Verstraete, Willy

2000-01-01

125

Variability of Total and Pathogenic Vibrio parahaemolyticus Densities in Northern Gulf of Mexico Water and Oysters  

Microsoft Academic Search

Vibrio parahaemolyticus is indigenous to coastal environments and a frequent cause of seafood-borne gas- troenteritis in the United States, primarily due to raw-oyster consumption. Previous seasonal-cycle studies of V. parahaemolyticus have identified water temperature as the strongest environmental predictor. Salinity has also been identified, although it is evident that its effect on annual variation is not as pronounced. The effects

A. M. Zimmerman; A. DePaola; J. C. Bowers; J. A. Krantz; J. L. Nordstrom; C. N. Johnson; D. J. Grimes

2007-01-01

126

DNA sequence of both chromosomes of the cholera pathogen Vibrio cholerae  

Microsoft Academic Search

Here we determine the complete genomic sequence of the Gram negative, ?-Proteobacterium Vibrio cholerae El Tor N16961 to be 4,033,460 base pairs (bp). The genome consists of two circular chromosomes of 2,961,146 bp and 1,072,314 bp that together encode 3,885 open reading frames. The vast majority of recognizable genes for essential cell functions (such as DNA replication, transcription, translation and

John F. Heidelberg; Jonathan A. Eisen; William C. Nelson; Rebecca A. Clayton; Michelle L. Gwinn; Robert J. Dodson; Daniel H. Haft; Erin K. Hickey; Jeremy D. Peterson; Lowell Umayam; Steven R. Gill; Karen E. Nelson; Timothy D. Read; Hervé Tettelin; Delwood Richardson; Maria D. Ermolaeva; Jessica Vamathevan; Steven Bass; Haiying Qin; Ioana Dragoi; Patrick Sellers; Lisa McDonald; Teresa Utterback; Robert D. Fleishmann; William C. Nierman; Owen White; Steven L. Salzberg; Hamilton O. Smith; Rita R. Colwell; John J. Mekalanos; J. Craig Venter; Claire M. Fraser

2000-01-01

127

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

SciTech Connect

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.

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

1989-11-01

128

Transoceanic spreading of pathogenic strains of Vibrio parahaemolyticus with distinctive genetic signatures in the recA gene.  

PubMed

Vibrio parahaemolyticus is an important human pathogen whose transmission is associated with the consumption of contaminated seafood. Consistent multilocus sequence typing for V. parahaemolyticus has shown difficulties in the amplification of the recA gene by PCR associated with a lack of amplification or a larger PCR product than expected. In one strain (090-96, Peru, 1996), the produced PCR product was determined to be composed of two recA fragments derived from different Vibrio species. To better understand this phenomenon, we sequenced the whole genome of this strain. The hybrid recA gene was found to be the result of a fragmentation of the original lineage-specific recA gene resulting from a DNA insertion of approximately 30 kb in length. This insert had a G+C content of 38.8%, lower than that of the average G+C content of V. parahaemolyticus (45.2%), and contained 19 ORFs, including a complete recA gene. This new acquired recA gene deviated 24% in sequence from the original recA and was distantly related to recA genes from bacteria of the Vibrionaceae family. The reconstruction of the original recA gene (recA3) identified the precursor as belonging to ST189, a sequence type reported previously only in Asian countries. The identification of this singular genetic feature in strains from Asia reveals new evidence for genetic connectivity between V. parahaemolyticus populations at both sides of the Pacific Ocean that, in addition to the previously described pandemic clone, supports the existence of a recurrent transoceanic spreading of pathogenic V. parahaemolyticus with the corresponding potential risk of pandemic expansion. PMID:25679989

González-Escalona, Narjol; Gavilan, Ronnie G; Brown, Eric W; Martinez-Urtaza, Jaime

2015-01-01

129

Transoceanic Spreading of Pathogenic Strains of Vibrio parahaemolyticus with Distinctive Genetic Signatures in the recA Gene  

PubMed Central

Vibrio parahaemolyticus is an important human pathogen whose transmission is associated with the consumption of contaminated seafood. Consistent multilocus sequence typing for V. parahaemolyticus has shown difficulties in the amplification of the recA gene by PCR associated with a lack of amplification or a larger PCR product than expected. In one strain (090–96, Peru, 1996), the produced PCR product was determined to be composed of two recA fragments derived from different Vibrio species. To better understand this phenomenon, we sequenced the whole genome of this strain. The hybrid recA gene was found to be the result of a fragmentation of the original lineage-specific recA gene resulting from a DNA insertion of approximately 30 kb in length. This insert had a G+C content of 38.8%, lower than that of the average G+C content of V. parahaemolyticus (45.2%), and contained 19 ORFs, including a complete recA gene. This new acquired recA gene deviated 24% in sequence from the original recA and was distantly related to recA genes from bacteria of the Vibrionaceae family. The reconstruction of the original recA gene (recA3) identified the precursor as belonging to ST189, a sequence type reported previously only in Asian countries. The identification of this singular genetic feature in strains from Asia reveals new evidence for genetic connectivity between V. parahaemolyticus populations at both sides of the Pacific Ocean that, in addition to the previously described pandemic clone, supports the existence of a recurrent transoceanic spreading of pathogenic V. parahaemolyticus with the corresponding potential risk of pandemic expansion. PMID:25679989

González-Escalona, Narjol; Gavilan, Ronnie G.; Brown, Eric W.; Martinez-Urtaza, Jaime

2015-01-01

130

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

PubMed

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

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

2015-03-01

131

Polysiphonia harveyi, WNC2005-126  

NSDL National Science Digital Library

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

Dr. Wilson Freshwater

2008-03-07

132

Presence of pathogenic Vibrio parahaemolyticus in waters and seafood from the Tunisian Sea.  

PubMed

The occurrence of the hemolysin genes, tdh and trh, in Vibrio parahaemolyticus strains isolated from environmental samples collected from various exported seafood products comprising of fishes and shellfish (Mytilus edulis and Crassostrea gigas) or seawater, was studied. Eight strains were confirmed as V. parahaemolyticus by toxR -based polymerase chain reaction and only one strain out of these 8 strains was positive for tdh and trh genes. Toxigenic V. parahaemolyticus isolates are present in Tunisian coastal areas and they may also be present in Tunisian exported seafood products. PMID:23430717

Khouadja, Sadok; Suffredini, Elisabetta; Spagnoletti, Matteo; Croci, Luciana; Colombo, Mauro M; Amina, Bakhrouf

2013-08-01

133

[Pathogenic Vibrios in oysters (Crassostrea rhizophorae) served at restaurants in Rio de Janeiro: a public health warning].  

PubMed

Forty oyster samples (Crassostrea rhizophorae) served raw in 15 restaurants in the city of Rio de Janeiro were evaluated in order to investigate the presence of Vibrio spp. The oyster samples were analyzed and subjected to enrichment in alkaline peptone water with the addition of 1 and 3% NaCl and incubated at 37 degrees C for 24 hours. Following this, the cultures were seeded onto thiosulfate citrate bile sucrose agar (TCBS) and the suspected colonies were subjected to biochemical characterization. Vibrio parahaemolyticus, Vibrio carchariae, Vibrio alginolyticus and Vibrio vulnificus were the main species (> 60%) isolated from raw oysters. PMID:17653465

Pereira, Christiane Soares; Viana, Célio Mauro; Rodrigues, Dália dos Prazeres

2007-01-01

134

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

PubMed

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

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

2014-10-01

135

Quorum sensing regulatory cascades control Vibrio fluvialis pathogenesis.  

PubMed

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

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

2013-08-01

136

Isolation, sequencing and characterization of cluster genes involved in the biosynthesis and utilization of the siderophore of marine fish pathogen Vibrio alginolyticus  

Microsoft Academic Search

In fish pathogen Vibrio alginolyticus MVP01, the isolated 11-gene cluster consisted of two divergently transcribed, Fe3+ and ferric uptake regulator (Fur) regulated operons, pvsABCDE and psuA-pvuABCDE, sharing high similarity with that related to siderophore biosynthesis and transportation locus in V. parahaemolyticus. Siderophore biosynthesis or utilization was blocked when pvsA and pvsD of the pvsABCDE operon or pvuA, pvuB and pvuE

Qiyao Wang; Qin Liu; Yue Ma; Lingyun Zhou; Yuanxing Zhang

2007-01-01

137

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

Microsoft Academic Search

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

Yanett Leyton; Carlos Riquelme

2010-01-01

138

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

PubMed Central

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

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

2013-01-01

139

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

PubMed

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

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

140

An evaluation of chromogenic substrates for characterization of serine protease produced by pathogenic Vibrio alginolyticus.  

PubMed

Four chromogenic substrates for characterizing serine protease of Vibrio alginolyticus were evaluated. The protease activity of bacterial extracellular products, or the fractions of 33 kD protease purified by the AKTA purifier system with various columns, was completely inhibited by ethylenediamine tetra-acetic acid, ethylene glycol-bis(beta-amino-ethyl ether) N,N,N',N'-tetraacetic acid (EGTA), antipain and phenylmethylsulphonyl fluoride (PMSF) using water-soluble substrates (azoalbumin and azocasein). It was only completely inhibited by antipain and PMSF using water-insoluble substrates (azocoll and hide powder azure). The protease activity was not, or only partially, inhibited by 1,10-phenanthroline and sodium dodecyl sulphate (SDS) using all four substrates. Since chelating agents and 1,10-phenanthroline are commonly employed as inhibitors to identify metalloprotease, the two water-soluble substrates may not be appropriate for this purpose, except for using 1,10-phenanthroline as an inhibitor. Chelating agents may be still applicable as inhibitors using water-insoluble substrates and 1,10-phenanthroline is highly recommended in the characterization for metalloprotease to avoid confusion. In the present study, the 33 kD protease was further confirmed as an SDS-resistant serine protease and not a metalloprotease. PMID:10413876

Chen, F R; Liu, P C; Lee, K K

1999-01-01

141

In vivo evaluation of pathogenicity of clinical and environmental isolates of Vibrio cholerae.  

PubMed

Thirty-three minimally passaged clinical and environmental isolates of Vibrio cholerae were examined for ability to survive and multiply in the upper bowel of infant mice and to elicit diarrhea. All of 21 smooth O-1 V. cholerae isolates from stool were able to multiply and elicit diarrhea. Three rough strains isolated from stool were unable to multiply or to elicit diarrhea. Two smooth O-1 isolates associated with cholera cases (from a sewer and a septic tank) also were able to cause disease. However, four O-1 strains and one non-O-1 strain from sources not associated with cholera cases did not cause mouse disease. A human gall bladder isolate was also avirulent, whereas a Louisiana shrimp isolated showed low mouse virulence. We conclude that smooth human diarrheal isolates of V. cholerae of serogroup O-1 are virulent for infant mice. Examination of sequential isolates from single patients showed that some strains isolated later in infection had a reduced ability to induce diarrhea. Comparison of epidemiologically related strains showed that an isolate from crab had a low ability to induce disease in infant mice, whereas the isolates from patients showed the expected ability to multiply and elicit diarrhea in mice. PMID:7399688

Sigel, S P; Lanier, S; Baselski, V S; Parker, C D

1980-06-01

142

Pathogenicity and Infection Cycle of Vibrio owensii in Larviculture of the Ornate Spiny Lobster (Panulirus ornatus)  

PubMed Central

The type strain of Vibrio owensii (DY05) was isolated during an epizootic of aquaculture-reared larvae (phyllosomas) of the ornate spiny lobster (Panulirus ornatus). V. owensii DY05 was formally demonstrated to be the etiological agent of a disease causing rapid and reproducible larval mortality with pathologies similar to those seen during disease epizootics. Vectored challenge via the aquaculture live feed organism Artemia (brine shrimp) caused consistent cumulative mortality rates of 84 to 89% after 72 h, in contrast to variable mortality rates seen after immersion challenge. Histopathological examination of vector-challenged phyllosomas revealed bacterial proliferation in the midgut gland (hepatopancreas) concomitant with epithelial cell necrosis. A fluorescent-protein-labeled V. owensii DY05 transconjugant showed dispersal of single cells in the foregut and hepatopancreas 6 h postexposure, leading to colonization of the entire hepatopancreas within 18 h and eventually systemic infection. V. owensii DY05 is a marine enteropathogen highly virulent to P. ornatus phyllosoma that uses vector-mediated transmission and release from host association to a planktonic existence to perpetuate transfer. This understanding of the infection process will improve targeted biocontrol strategies and enhance the prospects of commercially viable larviculture for this valuable spiny lobster species. PMID:22307306

Goulden, Evan F.; Hall, Michael R.; Bourne, David G.; Pereg, Lily L.

2012-01-01

143

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

PubMed Central

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

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

144

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

PubMed

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

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

2015-01-15

145

Identification of Pathogenic Vibrio Species by Multilocus PCR-Electrospray Ionization Mass Spectrometry and Its Application to Aquatic Environments of the Former Soviet Republic of Georgia? †  

PubMed Central

The Ibis T5000 is a novel diagnostic platform that couples PCR and mass spectrometry. In this study, we developed an assay that can identify all known pathogenic Vibrio species and field-tested it using natural water samples from both freshwater lakes and the Georgian coastal zone of the Black Sea. Of the 278 total water samples screened, 9 different Vibrio species were detected, 114 (41%) samples were positive for V. cholerae, and 5 (0.8%) samples were positive for the cholera toxin A gene (ctxA). All ctxA-positive samples were from two freshwater lakes, and no ctxA-positive samples from any of the Black Sea sites were detected. PMID:20118359

Whitehouse, Chris A.; Baldwin, Carson; Sampath, Rangarajan; Blyn, Lawrence B.; Melton, Rachael; Li, Feng; Hall, Thomas A.; Harpin, Vanessa; Matthews, Heather; Tediashvili, Marina; Jaiani, Ekaterina; Kokashvili, Tamar; Janelidze, Nino; Grim, Christopher; Colwell, Rita R.; Huq, Anwar

2010-01-01

146

Genomic taxonomy of vibrios  

PubMed Central

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

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

2009-01-01

147

Defences against oxidative stress in vibrios associated with corals.  

PubMed

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

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

2008-04-01

148

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

PubMed

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

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

1998-06-19

149

Evidence of a new metabolic capacity in an emerging diarrheal pathogen: lessons from the draft genomes of Vibrio fluvialis strains PG41 and I21563  

PubMed Central

Background Vibrio fluvialis is an emerging diarrheal pathogen for which no genome is currently available. In this work, draft genomes of two closely related clinical strains PG41 and I21563 have been explored. Results V. fluvialis strains PG41 and I21563 were sequenced on the Illumina HiSeq 1000 platform to obtain draft genomes of 5.3 Mbp and 4.4 Mbp respectively. Our genome data reveal the presence of genes involved in ethanolamine utilization, which is further experimentally confirmed by growth analysis. Conclusions Combined in silico and growth analysis establish a new metabolic capacity of V. fluvialis to harvest energy from ethanolamine. PMID:23895343

2013-01-01

150

A large-scale epidemiological study to identify bacteria pathogenic to Pacific oyster Crassostrea gigas and correlation between virulence and metalloprotease-like activity.  

PubMed

A 4-year bacteriological survey (2003-2007) of four molluscs cultivated in France and faced with mortality episodes was performed by the French shellfish pathology network. The more abundant bacteria isolated during 92 mortality episodes, occurring mainly in Pacific oyster Crassostrea gigas, were identified by genotyping methods. It allowed us both to confirm the representativeness of Vibrio splendidus and Vibrio aestuarianus bacterial strains and to identify both a large number of Vibrio harveyi-related strains mainly detected during 2007 oyster mortality outbreaks and to a lesser extent bacterial strains identified as Shewanella colwelliana. Because metalloprotease has been reported to constitute a virulence factor in a few Vibrio strains pathogenic for C. gigas, several bacterial strains isolated in this study were screened to evaluate their pathogenicity in C. gigas spat by experimental infection and their ability to produce metalloprotease-like activity in the culture supernatant fluids. A high level (84%) of concordant results between azocaseinase activities and virulence of strains was obtained in this study. Because bacterial metalloprotease activities appeared as a common feature of pathogenic bacteria strains associated with mortality events of C. gigas reared in France, this phenotypic test could be useful for the evaluation of virulence in bacterial strains associated with such mortality episodes. PMID:20012275

Saulnier, Denis; De Decker, Sophie; Haffner, Philippe; Cobret, Laetitia; Robert, Maeva; Garcia, Céline

2010-05-01

151

Roles of motility and flagellar structure in pathogenicity of Vibrio cholerae: analysis of motility mutants in three animal models.  

PubMed

Wild-type Vibrio cholerae of both El Tor and classical biotypes (strains N16961 and 395, respectively) and nonmotile mutant derivatives with and without flagellar structures were characterized in three different animal models: (i) the rabbit ileal loop, (ii) the removable intestinal tie adult rabbit diarrhea (RITARD) model, and (iii) the suckling mouse model. Both the wild-type strains and nonmotile mutants were toxinogenic in the rabbit ileal loop and the suckling mouse models. However, all of the nonmotile mutants produced significantly less fluid accumulation than did the wild-type parental strains. The two nonmotile mutants of strain N16961 did not adhere to rabbit ileal mucosa, but both nonmotile mutants derived from strain 395 exhibited adherence. In the RITARD model, the motile El Tor strains were more virulent than both the flagellate and aflagellate nonmotile mutants (all infected rabbits died within 18 h), while the nonmotile mutants, when fatalities occurred, required 78 to 105 h to produce a fatal outcome. Likewise, the motile classical parent 395 produced a fatal outcome within ca. 25 h, while nonmotile mutants required 69 to 96 h. The nonmotile flagellate strain KR31 was not significantly more virulent than the nonmotile aflagellate strain KR26. Of the two classical nonmotile mutants, KR1, which produces a coreless sheathlike structure, was clearly more virulent (5 of 10 rabbits died within 96 h), while KR3 (nonmotile, aflagellate) did not produce fatalities in any of the 10 rabbits tested. Similarly, no significant difference in diarrheagenicity or colonizing ability was detected between the two nonmotile mutants derived from the El Tor strain, but the classical nonmotile mutant with the coreless sheath caused significantly greater diarrhea and colonized for a longer time than did the isogenic nonmotile aflagellate strain, KR3. No significant differences between the nonmotile mutants were detected in competition studies done with suckling mice. Analysis of the wild-type and mutant strains in these three animal models clearly demonstrated a role for motility in V. cholerae pathogenicity, while analysis of only the nonmotile mutants derived from the classical parent suggested a role for flagellar structures. PMID:1855990

Richardson, K

1991-08-01

152

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

PubMed Central

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

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

2004-01-01

153

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

PubMed Central

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

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

2014-01-01

154

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

PubMed Central

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

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

2015-01-01

155

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

PubMed

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

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

2015-01-01

156

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

PubMed Central

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.

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

2015-01-01

157

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

PubMed

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

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

2011-03-01

158

Environmental parameters influence on the dynamics of total and pathogenic Vibrio parahaemolyticus densities in Crassostrea virginica harvested from Mexico's Gulf coast.  

PubMed

The influence of environmental parameters on the total and pathogenic Vibrio parahaemolyticus seasonal densities in American oysters (Crassostrea virginica) was evaluated for 1year. Harvesting site A yielded the highest mean densities of V. parahaemolyticus tlh+, tdh+/trh-, tdh-/trh+ and tdh+/trh+ during spring season at 2.57, 1.74, 0.36, and -0.40 log10MPN/g, respectively, and tdh+/orf8+ during winter season (0.90 log10MPN/g). V. parahaemolyticus tlh+ densities were associated to salinity (R(2)=0.372, P<0.022), tdh+/trh+ to turbidity (R(2)=0.597, P<0.035), and orf8+ to temperature, salinity, and pH (R(2)=0.964, P<0.001). The exposure to salinity and temperature conditions during winter and spring seasons regulated the dynamics of V. parahaemolyticus harboring potentially pathogenic genotypes within the oyster. The adaptive response of V. parahaemolyticus to seasonal environmental changes may lead to an increase in survival and virulence, threatening the seafood safety and increasing the risk of illness. PMID:25510545

López-Hernández, Karla M; Pardío-Sedas, Violeta T; Lizárraga-Partida, Leonardo; Williams, José de J; Martínez-Herrera, David; Flores-Primo, Argel; Uscanga-Serrano, Roxana; Rendón-Castro, Karla

2015-02-15

159

Effects of the pathogenic Vibrio tapetis on defence factors of susceptible and non-susceptible bivalve species  

E-print Network

(pallial cavity), pseudo-internal (extrapallial space), or internal compartment (adductor muscle). The most a bacterial pathogenicity particular to the host in which it causes a specific disease syndrome. Alterations

Allam, Bassem

160

Microcystin-producing and non-producing cyanobacterial blooms collected from the Central India harbor potentially pathogenic Vibrio cholerae.  

PubMed

On the basis of relative abundance, frequency and biovolume, the important value index ranks were assigned to individual cyanobacteria in phytoplankton samples collected from fourteen water resources of Central India. The mcyABDE genes were detected in all the blooms with Microcystis (-aeruginosa, -viridis, -panniformis, -botrys) as being the major constituent morphospecies. On the other hand, blooms composed of primarily Oscillatoria (-limosa,-agardhii, -laetevirens) along with Anabaena, Nostoc, Phormidium and Spirulina as sub-dominant forms exhibited quite a patchy distribution of one or the other mcy genes. Fifty percent of Microcystis- but none of the Oscillatoria dominant blooms produced microcystins-RR and desmethyl-RR at 0.03-0.41mgg(-1) bloom dry mass. Traces of dissolved microcystin was detected in lake water, which is well below the WHO guideline. Irrespective of cyanobacterial composition and microcystin production ability, during the study period 43-64% of the cyanobacterial bloom samples exhibited association of viable but nonculturable forms of Vibrio cholerae O1 and O139, as evident from amplification of the antigen genes. We believe that spread of endemic cholera is the major threat associated with harmful algal blooms. PMID:25682583

Chaturvedi, Prashant; Kumar Agrawal, Manish; Nath Bagchi, Suvendra

2015-05-01

161

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

PubMed

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

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

2013-06-01

162

DjlA, a Membrane-Anchored DnaJ-Like Protein, Is Required for Cytotoxicity of Clam Pathogen Vibrio tapetis to Hemocytes?  

PubMed Central

DjlA is an inner membrane cochaperone belonging to the DnaJ family, which has been shown to be involved in Legionella sp. pathogenesis. In this study, we explored the role of this protein in the physiology and virulence of Vibrio tapetis, the etiological agent of brown ring disease (BRD) in Manila clam (Ruditapes philippinarum). Analysis of the djlA locus in V. tapetis revealed a putative organization in an operon with a downstream gene that we designated duf924Vt, which encodes a conserved protein with an unknown function and has homologues in bacteria and eukaryotes. djlA mutants displayed a reduced growth rate and showed an important loss of cytotoxic activity against R. philippinarum hemocytes in vitro, which could be restored by extrachromosomal expression of wild-type djlAVt but not duf924Vt. These results are in keeping with the potential importance of DjlA for bacterial pathogenicity and open new perspectives for understanding the mechanism of action of this protein in the novel V. tapetis-R. philippinarum interaction model. PMID:18641167

Lakhal, Fatma; Bury-Moné, Stéphanie; Nomane, Yanoura; Le Goïc, Nelly; Paillard, Christine; Jacq, Annick

2008-01-01

163

Vibrio species as agents of elasmobranch disease  

Microsoft Academic Search

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

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

164

Vibrio parahaemolyticus  

MedlinePLUS

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

165

Vibrio vulnificus  

MedlinePLUS

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

166

Autecology of Vibrio vulnificus and Vibrio parahaemolyticus in tropical waters  

SciTech Connect

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

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

1988-12-31

167

Biodiversity of Vibrios  

PubMed Central

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

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

2004-01-01

168

Bacterial quorum sensing inhibitors: attractive alternatives for control of infectious pathogens showing multiple drug resistance.  

PubMed

Quorum sensing (QS) is a bacterial communication process that depends on the bacterial population density. It involves small diffusible signaling molecules which activate the expression of myriad genes that control diverse array of functions like bioluminescence, virulence, biofilm formation, sporulation, to name a few. Since QS is responsible for virulence in the clinically relevant bacteria, inhibition of QS appears to be a promising strategy to control these pathogenic bacteria. With indiscriminate use of antibiotics, there has been an alarming increase in the number of antibiotic resistant pathogens. Antibiotics are no longer the magic bullets they were once thought to be and therefore there is a need for development of new antibiotics and/or other novel strategies to combat the infections caused by multidrug resistant organisms. Quorum sensing inhibition or quorum quenching has been pursued as one of such novel strategies. While antibiotics kill or slow down the growth of bacteria, quorum sensing inhibitors (QSIs) or quorum quenchers (QQs) attenuate bacterial virulence. A large body of work on QS has been carried out in deadly pathogens like Pseudomonas aeruginosa, Staphylococcus aureus, Vibrio fischeri, V. harveyi, Escherichia coli and V. cholerae etc to unravel the mechanisms of QS as well as identify and study QSIs. This review describes various aspects of QS, QSI, different model systems to study these phenomena and recent patents on various QSIs. It suggests QSIs as attractive alternatives for controlling human, animal and plant pathogens and their utility in agriculture and other industries. PMID:23394143

Bhardwaj, Ashima K; Vinothkumar, Kittappa; Rajpara, Neha

2013-04-01

169

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

PubMed Central

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

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

2012-01-01

170

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

PubMed

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

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

2012-10-01

171

Putative Virulence Traits and Pathogenicity of Vibrio cholerae Non-O1, Non-O139 Isolates from Surface Waters in Kolkata, India?  

PubMed Central

Vibrio cholerae non-O1, non-O139 was isolated from natural surface waters from different sites sampled in diarrhea endemic zones in Kolkata, India. Twenty-one of these isolates were randomly selected and included in the characterization. The multiserogroup isolates were compared by their virulence traits with a group of clinical non-O1, non-O139 isolates from the same geographic area. Of the 21 environmental isolates, 6 and 14 strains belonged to Heiberg groups I and II, respectively. Three of the environmental isolates showed resistance to 2,2-diamine-6,7-diisopropylpteridine phosphate. All of the non-O1, non-O139 strains were positive for toxR, and except for one environmental isolate, none of them were positive for tcpA in the PCR assay. None of the isolates were positive for genes encoding cholera toxin (ctxA), heat-stable toxin (est), heat-labile toxin (elt), and Shiga toxin variants (stx) of Escherichia coli. Additionally, except for one environmental isolate (PC32), all were positive for the gene encoding El Tor hemolysin (hly). The culture supernatants of 86% (18 of 21) of the environmental isolates showed a distinct cytotoxic effect on HeLa cells, and some of these strains also produced cell-rounding factor. The lipase, protease, and cell-associated hemagglutination activities and serum resistance properties of the environmental and clinical isolates did not differ much. However, seven environmental isolates exhibited very high hemolytic activities (80 to 100%), while none of the clinical strains belonged to this group. The environmental isolates manifested three adherence patterns, namely, carpet-like, diffuse, and aggregative adherence, and the clinical isolates showed diffuse adherence on HeLa cells. Of the 11 environmental isolates tested for enteropathogenic potential, 8 (73%) induced positive fluid accumulation (?100) in a mouse model, and the reactivities of these isolates were comparable to those of clinical strains of non-O1, non-O139 and toxigenic O139 V. cholerae. Comparison of the counts of the colonized environmental and clinical strains in the mouse intestine showed that the organisms of both groups had similar colonizing efficiencies. These findings indicate the presence of potentially pathogenic V. cholerae non-O1, non-O139 strains in surface waters of the studied sites in Kolkata. PMID:18641168

Bag, Prasanta K.; Bhowmik, Poulami; Hajra, Tapas K.; Ramamurthy, T.; Sarkar, Pradipta; Majumder, Mrinmoyee; Chowdhury, Goutam; Das, Suresh C.

2008-01-01

172

Ethanolamine utilization in Vibrio alginolyticus  

PubMed Central

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

2012-01-01

173

Vibrio parahaemolyticus: A concern of seafood safety  

Microsoft Academic Search

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

Yi-Cheng Su; Chengchu Liu

2007-01-01

174

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

PubMed Central

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

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

2011-01-01

175

Vibrio vulnificus  

Microsoft Academic Search

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

James D. Oliver

176

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

PubMed

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

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

2014-12-01

177

The international standard ISO/TS 21872-1 to study the occurence of total and pathogenic Vibrio parahaemolyticus and Vibrio cholerae in seafood: ITS improvement by use of a chromogenic medium and PCR.  

PubMed

During two surveys conducted in 2008 and 2009, the culture method described in the international standard ISO/TS 21872-1 was applied to the detection of Vibrio parahaemolyticus and Vibrio cholerae in 112 living bivalve mollusc samples, with a chromogenic medium used in addition to the TCBS agar, as second selective isolation medium and for enumeration of V. parahaemolyticus and V. cholerae by surface inoculation. A PCR method for detection of these 2 Vibrio species and the hemolysin genes tdh and trh, was applied in parallel. In 2009, the survey was extended to finfish fillets and crustaceans. PCR was also used for species confirmation of characteristic colonies. The identity of the PCR products, specifically targeting V. parahaemolyticus, was checked by sequencing. Occurrence of V. parahaemolyticus and V. cholerae isolates in living bivalve molluscs ranged from 30.4% to 32.6% and from 1.4% to 4.7% respectively. In frozen crustaceans (2009 survey) V. parahaemolyticus and V. cholerae isolates were respectively found in 45% and 10% of the samples. No V. parahaemolyticus or V. cholerae was detected in frozen fish fillets, neither by the ISO method nor by PCR. In 2009, enteropathogenic V. parahaemolyticus (trh+) was isolated from 4 out of 43 oyster samples while the trh gene was present in V. alginolyticus strains and in samples where V. parahaemolyticus was not detected (9 over 112 samples). The ISO method failed to isolate V. parahaemolyticus in 44% to 53% of the living bivalve molluscs where PCR detected the toxR gene specific of V. parahaemolyticus (Vp-toxR). Our results highlighted the need for a revision of the ISO/TS 21872-1 standard, at least, for analysis of living bivalve molluscs, and confirmed the increasing concern of enteropathogenic V. parahaemolyticus in French bivalve molluscs. Enrichment at 41.5°C was questioned and some reliable solutions for the improvement of the ISO/TS 21872-1 method, such as the PCR method for screening of positive samples and confirmation of colonies, were pointed out. PMID:22682545

Rosec, Jean-Philippe; Causse, Véronique; Cruz, Barbara; Rauzier, Jean; Carnat, Laurence

2012-07-01

178

Mixed diarrhoeal infection caused by Vibrio cholerae and several other enteric pathogens in a 4-year-old child returning to Germany from Pakistan.  

PubMed

We report a mixed enteric infection in a 4-y-old child who returned from Pakistan with fever, vomiting and profuse diarrhoea leading to severe dehydration. Vibrio cholerae O1, Salmonella paratyphi A and Campylobacter coli were cultured from stool. Furthermore, Giardia lamblia antigen and hepatitis A RNA were detected. This is the first paediatric cholera case seen in Frankfurt/Main. PMID:15764195

Enzensberger, Ruxandra; Besier, Silke; Baumgärtner, Nicole; Brade, Volker

2005-01-01

179

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

Microsoft Academic Search

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

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

2001-01-01

180

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

PubMed Central

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

Venkateswaran, Kasthuri; Dohmoto, Nobuhiko; Harayama, Shigeaki

1998-01-01

181

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

PubMed

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

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

1995-01-01

182

Obacunone represses Salmonella pathogenicity islands 1 and 2 in an envZ-dependent fashion.  

PubMed

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

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

2012-10-01

183

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

PubMed Central

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

Baross, J.; Liston, J.

1970-01-01

184

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

ERIC Educational Resources Information Center

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

Hrizo, Stacy L.; Kaufmann, Nancy

2009-01-01

185

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

PubMed Central

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

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

2014-01-01

186

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

PubMed Central

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

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

1988-01-01

187

Antimicrobial Resistance in Vibrios  

Microsoft Academic Search

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

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

188

Autoinduction in Erwinia amylovora: Evidence of an Acyl-Homoserine Lactone Signal in the Fire Blight Pathogen  

PubMed Central

Erwinia amylovora causes fire blight disease of apple, pear, and other members of the Rosaceae. Here we present the first evidence for autoinduction in E. amylovora and a role for an N-acyl-homoserine lactone (AHL)-type signal. Two major plant virulence traits, production of extracellular polysaccharides (amylovoran and levan) and tolerance to free oxygen radicals, were controlled in a bacterial-cell-density-dependent manner. Two standard autoinducer biosensors, Agrobacterium tumefaciens NTL4 and Vibrio harveyi BB886, detected AHL in stationary-phase cultures of E. amylovora. A putative AHL synthase gene, eamI, was partially sequenced, which revealed homology with autoinducer genes from other bacterial pathogens (e.g., carI, esaI, expI, hsII, yenI, and luxI). E. amylovora was also found to carry eamR, a convergently transcribed gene with homology to luxR AHL activator genes in pathogens such as Erwinia carotovora. Heterologous expression of the Bacillus sp. strain A24 acyl-homoserine lactonase gene aiiA in E. amylovora abolished induction of AHL biosensors, impaired extracellular polysaccharide production and tolerance to hydrogen peroxide, and reduced virulence on apple leaves. PMID:15838048

Molina, Lázaro; Rezzonico, Fabio; Défago, Geneviève; Duffy, Brion

2005-01-01

189

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

PubMed Central

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

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

2010-01-01

190

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

PubMed

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

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

2010-08-01

191

Complete Genome Sequence of the Marine Fish Pathogen Vibrio anguillarum Harboring the pJM1 Virulence Plasmid and Genomic Comparison with Other Virulent Strains of V. anguillarum and V. ordalii ? †  

PubMed Central

We dissected the complete genome sequence of the O1 serotype strain Vibrio anguillarum 775(pJM1) and determined the draft genomic sequences of plasmidless strains of serotype O1 (strain 96F) and O2? (strain RV22) and V. ordalii. All strains harbor two chromosomes, but 775 also harbors the virulence plasmid pJM1, which carries the anguibactin-producing and cognate transport genes, one of the main virulence factors of V. anguillarum. Genomic analysis identified eight genomic islands in chromosome 1 of V. anguillarum 775(pJM1) and two in chromosome 2. Some of them carried potential virulence genes for the biosynthesis of O antigens, hemolysins, and exonucleases as well as others for sugar transport and metabolism. The majority of genes for essential cell functions and pathogenicity are located on chromosome 1. In contrast, chromosome 2 contains a larger fraction (59%) of hypothetical genes than does chromosome 1 (42%). Chromosome 2 also harbors a superintegron, as well as host “addiction” genes that are typically found on plasmids. Unique distinctive properties include homologues of type III secretion system genes in 96F, homologues of V. cholerae zot and ace toxin genes in RV22, and the biofilm formation syp genes in V. ordalii. Mobile genetic elements, some of them possibly originated in the pJM1 plasmid, were very abundant in 775, resulting in the silencing of specific genes, with only few insertions in the 96F and RV22 chromosomes. PMID:21576332

Naka, Hiroaki; Dias, Graciela M.; Thompson, Cristiane C.; Dubay, Christopher; Thompson, Fabiano L.; Crosa, Jorge H.

2011-01-01

192

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

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

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

2015-02-01

193

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

PubMed Central

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

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

2012-01-01

194

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

NASA Technical Reports Server (NTRS)

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

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

1981-01-01

195

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

PubMed

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

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

2001-04-01

196

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

PubMed Central

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

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

2005-01-01

197

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

Microsoft Academic Search

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

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

2001-01-01

198

Vibrio and Pregnancy  

MedlinePLUS

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

199

Vibrio cholerae Requires rpoS for Efficient Intestinal Colonization  

Microsoft Academic Search

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

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

2000-01-01

200

Sensitivity of vibrios to sanguinarine  

Microsoft Academic Search

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

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

1983-01-01

201

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 Central

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

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

2015-01-01

202

New Vibrio species associated to molluscan microbiota: a review.  

PubMed

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

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

2014-01-01

203

New Vibrio species associated to molluscan microbiota: a review  

PubMed Central

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

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

2014-01-01

204

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

PubMed

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

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

2012-08-01

205

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

PubMed

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

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

2014-09-01

206

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

NASA Astrophysics Data System (ADS)

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

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

2006-04-01

207

Comparative genomics of clinical and environmental Vibrio mimicus  

PubMed Central

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

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

2010-01-01

208

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

Microsoft Academic Search

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

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

209

Survival of Vibrio anguillarum and Vibrio salmonicida at different salinities.  

PubMed Central

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

Hoff, K A

1989-01-01

210

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

PubMed Central

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

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

2014-01-01

211

Complete Genome Sequence of Vibrio alginolyticus ATCC 17749T  

PubMed Central

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

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

2015-01-01

212

Ecology of Vibrio parahaemolyticus and Vibrio vulnificus in the Coastal and Estuarine Waters of Louisiana, Maryland, Mississippi, and Washington (United States)  

PubMed Central

Vibrio parahaemolyticus and Vibrio vulnificus, which are native to estuaries globally, are agents of seafood-borne or wound infections, both potentially fatal. Like all vibrios autochthonous to coastal regions, their abundance varies with changes in environmental parameters. Sea surface temperature (SST), sea surface height (SSH), and chlorophyll have been shown to be predictors of zooplankton and thus factors linked to vibrio populations. The contribution of salinity, conductivity, turbidity, and dissolved organic carbon to the incidence and distribution of Vibrio spp. has also been reported. Here, a multicoastal, 21-month study was conducted to determine relationships between environmental parameters and V. parahaemolyticus and V. vulnificus populations in water, oysters, and sediment in three coastal areas of the United States. Because ecologically unique sites were included in the study, it was possible to analyze individual parameters over wide ranges. Molecular methods were used to detect genes for thermolabile hemolysin (tlh), thermostable direct hemolysin (tdh), and tdh-related hemolysin (trh) as indicators of V. parahaemolyticus and the hemolysin gene vvhA for V. vulnificus. SST and suspended particulate matter were found to be strong predictors of total and potentially pathogenic V. parahaemolyticus and V. vulnificus. Other predictors included chlorophyll a, salinity, and dissolved organic carbon. For the ecologically unique sites included in the study, SST was confirmed as an effective predictor of annual variation in vibrio abundance, with other parameters explaining a portion of the variation not attributable to SST. PMID:22865080

Bowers, John C.; Griffitt, Kimberly J.; Molina, Vanessa; Clostio, Rachel W.; Pei, Shaofeng; Laws, Edward; Paranjpye, Rohinee N.; Strom, Mark S.; Chen, Arlene; Hasan, Nur A.; Huq, Anwar; Noriea, Nicholas F.; Grimes, D. Jay; Colwell, Rita R.

2012-01-01

213

Ecology of Vibrio parahaemolyticus and Vibrio vulnificus in the coastal and estuarine waters of Louisiana, Maryland, Mississippi, and Washington (United States).  

PubMed

Vibrio parahaemolyticus and Vibrio vulnificus, which are native to estuaries globally, are agents of seafood-borne or wound infections, both potentially fatal. Like all vibrios autochthonous to coastal regions, their abundance varies with changes in environmental parameters. Sea surface temperature (SST), sea surface height (SSH), and chlorophyll have been shown to be predictors of zooplankton and thus factors linked to vibrio populations. The contribution of salinity, conductivity, turbidity, and dissolved organic carbon to the incidence and distribution of Vibrio spp. has also been reported. Here, a multicoastal, 21-month study was conducted to determine relationships between environmental parameters and V. parahaemolyticus and V. vulnificus populations in water, oysters, and sediment in three coastal areas of the United States. Because ecologically unique sites were included in the study, it was possible to analyze individual parameters over wide ranges. Molecular methods were used to detect genes for thermolabile hemolysin (tlh), thermostable direct hemolysin (tdh), and tdh-related hemolysin (trh) as indicators of V. parahaemolyticus and the hemolysin gene vvhA for V. vulnificus. SST and suspended particulate matter were found to be strong predictors of total and potentially pathogenic V. parahaemolyticus and V. vulnificus. Other predictors included chlorophyll a, salinity, and dissolved organic carbon. For the ecologically unique sites included in the study, SST was confirmed as an effective predictor of annual variation in vibrio abundance, with other parameters explaining a portion of the variation not attributable to SST. PMID:22865080

Johnson, Crystal N; Bowers, John C; Griffitt, Kimberly J; Molina, Vanessa; Clostio, Rachel W; Pei, Shaofeng; Laws, Edward; Paranjpye, Rohinee N; Strom, Mark S; Chen, Arlene; Hasan, Nur A; Huq, Anwar; Noriea, Nicholas F; Grimes, D Jay; Colwell, Rita R

2012-10-01

214

Long-term effects of ocean warming on vibrios  

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

215

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

PubMed Central

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

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

2014-01-01

216

Vibrio chromosomes share common history  

E-print Network

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

Kirkup, Benjamin C.

217

Vibrio chromosomes share common history  

E-print Network

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

Kirkup, Benjamin C.

218

Abundance and distribution of Vibrio cholerae, V. parahaemolyticus, and V. vulnificus following a major freshwater intrusion into the Mississippi Sound.  

PubMed

In response to a major influx of freshwater to the Mississippi Sound following the opening of the Bonnet Carre Spillway, water samples were collected from three sites along the Mississippi shoreline to assess the impact of altered salinity on three pathogenic Vibrio species. Salinity readings across the affected area during the 2011 sample period ranged from 1.4 to 12.9 ppt (mean = 7.0) and for the 2012 sample period from 14.1 to 23.6 ppt (mean = 19.8). Analyses of the data collected in 2011 showed a reduction in densities of Vibrio parahaemolyticus and Vibrio vulnificus with a concurrent increase of Vibrio cholerae numbers, with V. cholerae becoming the only Vibrio detected once salinity readings dropped to 6 ppt. Follow-up samples taken in 2012 after recovery of the salinity in the sound showed that the relative densities of the three pathogenic vibrios had reverted back to normal levels. This study shows that although the spillway was open but a few weeks and the effects were therefore time limited, the Mississippi River water had a profound, if temporary, effect on Vibrio ecology in the Mississippi Sound. PMID:23494573

Griffitt, Kimberly J; Grimes, D Jay

2013-04-01

219

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

PubMed Central

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

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

2015-01-01

220

Transformation of Vibrio cholerae by plasmid DNA.  

PubMed

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

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

1991-08-30

221

Occurrence of Vibrio Pathotypes in the Final Effluents of Five Wastewater Treatment Plants in Amathole and Chris Hani District Municipalities in South Africa  

PubMed Central

We assessed the occurrence of Vibrio pathogens in the final effluents of five wastewater treatment plants (WWTPs) located in Amathole and Chris Hani District Municipalities in South Africa over a 12 months period between September 2012 and August 2013 using standard membrane filtration technique followed by cultivation on thiosulphate citrate-bile salts-sucrose (TCBS) agar. The identities of the presumptive Vibrio isolates were confirmed using polymerase chain reaction (PCR) including delineation into V. parahaemolyticus, V. vulnificus and V. fluvialis pathotypes. The counts of Vibrio spp. varied with months in all the study sites and ranged in the order of 101 and 104 CFU/100mL. Vibrio distribution also showed seasonality with high counts being obtained in autumn and spring (p < 0.05). Prevalence of Vibrio spp. among the five WWTPs also differed significantly (p < 0.05). Of the 300 isolates that were confirmed as belonging to the Vibrio genus, 29% (86) were V. fluvialis, 28% (84) were V. vulnificus and 12% (35) were V. parahaemolyticus. The isolation of Vibrio pathogens from the final effluent suggests that this pathogen is in circulation in some pockets of the population and that the WWTPs under study do not efficiently remove bacterial pathogens from the wastewater and consequently are threats to public health. PMID:25093653

Nongogo, Vuyokazi; Okoh, Anthony I.

2014-01-01

222

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

PubMed

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

Machado, A; Bordalo, A A

2014-09-01

223

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

PubMed

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

Eiler, Alexander; Bertilsson, Stefan

2006-11-01

224

Vibrio Infections and Surveillance in Maryland, 2002–2008  

PubMed Central

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

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

2013-01-01

225

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

PubMed

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

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

2015-06-01

226

Prevalence and characterisation of non-cholerae Vibrio spp. in final effluents of wastewater treatment facilities in two districts of the Eastern Cape Province of South Africa: implications for public health.  

PubMed

Vibrios and other enteric pathogens can be found in wastewater effluents of a healthy population. We assessed the prevalence of three non-cholerae vibrios in wastewater effluents of 14 wastewater treatment plants (WWTP) in Chris Hani and Amathole district municipalities in the Eastern Cape Province of South Africa for a period of 12 months. With the exception of WWTP10 where presumptive vibrios were not detected in summer and spring, presumptive vibrios were detected in all seasons in other WWTP effluents. When a sample of 1,000 presumptive Vibrio isolates taken from across all sampling sites were subjected to molecular confirmation for Vibrio, 668 were confirmed to belong to the genus Vibrio, giving a prevalence rate of 66.8 %. Further, molecular characterisation of 300 confirmed Vibrio isolates revealed that 11.6 % (35) were Vibrio parahaemolyticus, 28.6 % (86) were Vibrio fluvialis and 28 % (84) were Vibrio vulnificus while 31.8 % (95) belonged to other Vibrio spp. not assayed for in this study. Antibiogram profiling of the three Vibrio species showed that V. parahaemolyticus was ?50 % susceptible to 8 of the test antibiotics and ?50 % resistant to only 5 of the 13 test antibiotics, while V. vulnificus showed a susceptibility profile of ?50 % to 7 of the test antibiotics and a resistance profile of ?50 % to 6 of the 13 test antibiotics. V. fluvialis showed ?50 % resistance to 8 of the 13 antibiotics used while showing ?50 % susceptibility to only 4 antibiotics used. All three Vibrio species were susceptible to gentamycin, cefuroxime, meropenem and imipenem. Multiple antibiotic resistance patterns were also evident especially against such antibiotics as tetracyclin, polymixin B, penicillin G, sulfamethazole and erythromycin against which all Vibrio species were resistant. These results indicate a significant threat to public health, more so in the Eastern Cape Province of South Africa which is characterised by widespread poverty, with more than a third of the population directly relying on surface water sources for drinking and daily use. PMID:25167817

Okoh, Anthony I; Sibanda, Timothy; Nongogo, Vuyokazi; Adefisoye, Martins; Olayemi, Osuolale O; Nontongana, Nolonwabo

2015-02-01

227

Distribution of Virulence Genes in Clinical and Environmental Vibrio cholerae Strains in Bangladesh  

PubMed Central

Vibrio cholerae, an environmental organism, is a facultative human pathogen. Here, we report the virulence profiles, comprising 18 genetic markers, of 102 clinical and 692 environmental V. cholerae strains isolated in Bangladesh between March 2004 and January 2006, showing the variability of virulence determinants within the context of public health. PMID:23872570

Hasan, Nur A.; Ceccarelli, Daniela; Grim, Christopher J.; Taviani, Elisa; Choi, Jinna; Sadique, Abdus; Alam, Munirul; Siddique, Abul K.; Sack, R. Bradley; Huq, Anwar

2013-01-01

228

Distribution of virulence genes in clinical and environmental Vibrio cholerae strains in Bangladesh.  

PubMed

Vibrio cholerae, an environmental organism, is a facultative human pathogen. Here, we report the virulence profiles, comprising 18 genetic markers, of 102 clinical and 692 environmental V. cholerae strains isolated in Bangladesh between March 2004 and January 2006, showing the variability of virulence determinants within the context of public health. PMID:23872570

Hasan, Nur A; Ceccarelli, Daniela; Grim, Christopher J; Taviani, Elisa; Choi, Jinna; Sadique, Abdus; Alam, Munirul; Siddique, Abul K; Sack, R Bradley; Huq, Anwar; Colwell, Rita R

2013-09-01

229

Incidence of highly genetically diversified Vibrio parahaemolyticus in seafood imported from Asian countries  

Microsoft Academic Search

Vibrio parahaemolyticus is an important pathogen of humans and aquacultured animals, especially in Asian countries. In this study, we examined 686 samples of seafood imported from Hong Kong, Indonesia, Thailand and Vietnam for V. parahaemolyticus. V. parahaemolyticus was recovered from 315 (45.9%) samples. The incidence of V. parahaemolyticus in products from Hong Kong and Thailand was markedly higher than the

H.-C Wong; M.-C Chen; S.-H Liu; D.-P Liu

1999-01-01

230

Murine macrophage inflammatory cytokine production and immune activation in response to Vibrio parahaemolyticus infection  

Technology Transfer Automated Retrieval System (TEKTRAN)

Vibrio parahaemolyticus is the most common cause of bacterial seafood-related illness in the United States. Currently, there is a dearth of literature regarding immunity to infection with this pathogen. Here we studied V. parahaemolyticus-infected RAW 264.7 murine macrophage detecting both pro- and...

231

Characterization of the Vibrio cholerae vexAB and vexCD efflux systems  

Microsoft Academic Search

Vibrio cholerae is an important human pathogen that causes the diarrheal disease cholera. Colonization of the human host is dependent upon coordinated expression of several virulence factors in response to as yet unknown environmental cues. Bile acids have been implicated in the in vitro regulation of several V. cholerae genes, including those involved in motility, chemotaxis, outer membrane protein production,

James E. Bina; Daniele Provenzano; Chunmei Wang; Xiaowen R. Bina; John J. Mekalanos

2006-01-01

232

Vibrio natriegens: A Rapidly Growing Micro-Organism Ideally Suited for Class Experiments  

ERIC Educational Resources Information Center

Describes five microbiological experiments using the marine organism Vibrio natriegens. This organism is highly suitable for laboratory work because it is non-pathogenic and grows extremely rapidly, having the distinction of the lowest mean generation time yet recorded (9.8 minutes). (JR)

Mullenger, L.; Gill, Nijole R.

1973-01-01

233

Crystal Structure of the Extracellular Protein Secretion NTPase EpsE of Vibrio cholerae  

Microsoft Academic Search

Type II secretion systems consist of an assembly of 12–15 Gsp proteins responsible for transporting a variety of virulence factors across the outer membrane in several pathogenic bacteria. In Vibrio cholerae, the major virulence factor cholera toxin is secreted by the Eps Type II secretion apparatus consisting of 14 Eps proteins. One of these, EpsE, is a cytoplasmic putative NTPase

Mark A. Robien; Brian E. Krumm; Maria Sandkvist; Wim G. J. Hol

2003-01-01

234

Vibrio Zinc-Metalloprotease Causes Photoinactivation of Coral Endosymbionts and Coral Tissue Lesions  

PubMed Central

Background Coral diseases are emerging as a serious threat to coral reefs worldwide. Of nine coral infectious diseases, whose pathogens have been characterized, six are caused by agents from the family Vibrionacae, raising questions as to their origin and role in coral disease aetiology. Methodology/Principal Findings Here we report on a Vibrio zinc-metalloprotease causing rapid photoinactivation of susceptible Symbiodinium endosymbionts followed by lesions in coral tissue. Symbiodinium photosystem II inactivation was diagnosed by an imaging pulse amplitude modulation fluorometer in two bioassays, performed by exposing Symbiodinium cells and coral juveniles to non-inhibited and EDTA-inhibited supernatants derived from coral white syndrome pathogens. Conclusion/Significance These findings demonstrate a common virulence factor from four phylogenetically related coral pathogens, suggesting that zinc-metalloproteases may play an important role in Vibrio pathogenicity in scleractinian corals. PMID:19225559

Sussman, Meir; Mieog, Jos C.; Doyle, Jason; Victor, Steven; Willis, Bette L.; Bourne, David G.

2009-01-01

235

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

PubMed

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

Nie, Qing; Yue, Xin; Liu, Baozhong

2015-04-01

236

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

PubMed Central

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

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

2009-01-01

237

Ecology of Vibrio vulnificus in Estuarine Waters of Eastern North Carolina  

PubMed Central

While several studies on the ecology of Vibrio vulnificus in Gulf Coast environments have been reported, there is little information on the distribution of this pathogen in East Coast waters. Thus, we conducted a multiyear study on the ecology of V. vulnificus in estuarine waters of the eastern United States, employing extensive multiple regression analyses to reveal the major environmental factors controlling the presence of this pathogen, and of Vibrio spp., in these environments. Monthly field samplings were conducted between July 2000 and April 2002 at six different estuarine sites along the eastern coast of North Carolina. At each site, water samples were taken and nine physicochemical parameters were measured. V. vulnificus isolates, along with estuarine bacteria, Vibrio spp., Escherichia coli organisms, and total coliforms, were enumerated in samples from each site by using selective media. During the last 6 months of the study, sediment samples were also analyzed for the presence of vibrios, including V. vulnificus. Isolates were confirmed as V. vulnificus by using hemolysin gene PCR or colony hybridization. V. vulnificus was isolated only when water temperatures were between 15 and 27°C, and its presence correlated with water temperature and dissolved oxygen and vibrio levels. Levels of V. vulnificus in sediments were low, and no evidence for an overwintering in this environment was found. Multiple regression analysis indicated that vibrio levels were controlled primarily by temperature, turbidity, and levels of dissolved oxygen, estuarine bacteria, and coliforms. Water temperature accounted for most of the variability in the concentrations of both V. vulnificus (47%) and Vibrio spp. (48%). PMID:12788759

Pfeffer, Courtney S.; Hite, M. Frances; Oliver, James D.

2003-01-01

238

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

Microsoft Academic Search

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

PAULA I. WATNICK; KARLA JEAN FULLNER; ROBERTO KOLTER

1999-01-01

239

Exoproteome and Secretome Derived Broad Spectrum Novel Drug and Vaccine Candidates in Vibrio cholerae Targeted by Piper betel Derived Compounds  

PubMed Central

Vibrio cholerae is the causal organism of the cholera epidemic, which is mostly prevalent in developing and underdeveloped countries. However, incidences of cholera in developed countries are also alarming. Because of the emergence of new drug-resistant strains, even though several generic drugs and vaccines have been developed over time, Vibrio infections remain a global health problem that appeals for the development of novel drugs and vaccines against the pathogen. Here, applying comparative proteomic and reverse vaccinology approaches to the exoproteome and secretome of the pathogen, we have identified three candidate targets (ompU, uppP and yajC) for most of the pathogenic Vibrio strains. Two targets (uppP and yajC) are novel to Vibrio, and two targets (uppP and ompU) can be used to develop both drugs and vaccines (dual targets) against broad spectrum Vibrio serotypes. Using our novel computational approach, we have identified three peptide vaccine candidates that have high potential to induce both B- and T-cell-mediated immune responses from our identified two dual targets. These two targets were modeled and subjected to virtual screening against natural compounds derived from Piper betel. Seven compounds were identified first time from Piper betel to be highly effective to render the function of these targets to identify them as emerging potential drugs against Vibrio. Our preliminary validation suggests that these identified peptide vaccines and betel compounds are highly effective against Vibrio cholerae. Currently we are exhaustively validating these targets, candidate peptide vaccines, and betel derived lead compounds against a number of Vibrio species. PMID:23382822

Barh, Debmalya; Barve, Neha; Gupta, Krishnakant; Chandra, Sudha; Jain, Neha; Tiwari, Sandeep; Leon-Sicairos, Nidia; Canizalez-Roman, Adrian; Rodrigues dos Santos, Anderson; Hassan, Syed Shah; Almeida, Síntia; Thiago Jucá Ramos, Rommel; Augusto Carvalho de Abreu, Vinicius; Ribeiro Carneiro, Adriana; de Castro Soares, Siomar; Luiz de Paula Castro, Thiago; Miyoshi, Anderson; Silva, Artur; Kumar, Anil; Narayan Misra, Amarendra; Blum, Kenneth; Braverman, Eric R.; Azevedo, Vasco

2013-01-01

240

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

PubMed Central

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

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

2010-01-01

241

Endophthalmitis Caused by Vibrio alginolyticus?  

PubMed Central

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

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

2009-01-01

242

VIBRIO VULNIFICUS EDUCATION WORKSHOPS / MATERIALS  

EPA Science Inventory

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

243

CT gene modulate differential expression of chitinase gene under variant habitats in Vibrio cholerae  

PubMed Central

Objective To investigate the interrelation of cholera toxin gene (CT gene) in expression of chitinase gene under different pH conditions among pathogenic and Non-pathogenic strains of Vibrio cholera (V. cholera). Methods The chitinase assay well diffusion method and calorimetric chitinase assay were performed. Further, time depended chitinase activity among pathogenic and nonpathogenic strain was evaluated with control as Escherichia coli. The expressed protein in variant environment was purified by cascade of chromatographic techniques. The partially purified protein was analyzed by SDS-PAGE in both the strain of V. cholera. Results The results have shown differential expression of chitinase gene among vibrio in time depended chitinase activity, purification of expressed protein and SDS-PAGE analysis. Conclusions From the current study, two conclusions came in picture, habitat is prime factor that regulation of chitin gene expression among many bacterial strains, second, moreover among the vibrio pathogenic strains (CT+) expression of chitinase gene is more precisely regulated by CT gene rather than external environments while in non-pathogenic strain ( CT-) completely absent.

Verma, Yogendra Kumar; Verma, Mahendra Kumar

2013-01-01

244

Effect of temperature on growth of Vibrio parahaemolyticus [corrected] and Vibrio vulnificus in flounder, salmon sashimi and oyster meat.  

PubMed

Vibrio parahaemolyticus and Vibrio vulnificus are the major pathogenic Vibrio species which contaminate ready-to-eat seafood. The purpose of this study was to evaluate the risk of human illness resulting from consumption of ready-to-eat seafood such as sashimi and raw oyster meat due to the presence of V. parahaemolyticus and V. vulnificus. We compared the growth kinetics of V. parahaemolyticus and V. vulnificus strains in broth and ready-to-eat seafood, including flounder and salmon sashimi, as a function of temperature. The growth kinetics of naturally occurring V. vulnificus in raw oyster meat was also evaluated. The minimum growth temperatures of V. parahaemolyticus and V. vulnificus in broth were 13 °C and 11 °C, respectively. Overall, significant differences in lag time (LT) and specific growth rate (SGR) values between flounder and salmon sashimi were observed at temperatures ranging from 13 °C to 30 °C (p < 0.05). The growth of naturally occurring V. vulnificus reached stationary phase at ~4 log CFU/g in oysters, regardless of the storage temperature. This data indicates that the population of V. vulnificus in oysters did not reach the maximum population density as observed in the broth, where growth of V. vulnificus and V. parahaemolyticus isolated from oysters grew up to >8 log CFU/mL. PMID:23330227

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

2012-12-01

245

Environmental influences on Vibrio populations in northern temperate and boreal coastal waters (Baltic and Skagerrak Seas).  

PubMed

Even if many Vibrio spp. are endemic to coastal waters, their distribution in northern temperate and boreal waters is poorly studied. To identify environmental factors regulating Vibrio populations in a salinity gradient along the Swedish coastline, we combined Vibrio-specific quantitative competitive PCR with denaturant gradient gel electrophoresis-based genotyping. The total Vibrio abundance ranged from 4 x 10(3) to 9.6 x 10(4) cells liter(-1), with the highest abundances in the more saline waters of the Skagerrak Sea. Several Vibrio populations were present throughout the salinity gradient, with abundances of single populations ranging from 5 x 10(2) to 7 x 10(4) cells liter(-1). Clear differences were observed along the salinity gradient, where three populations dominated the more saline waters of the Skagerrak Sea and two populations containing mainly representatives of V. anguillarum and V. aestuarianus genotypes were abundant in the brackish waters of the Baltic Sea. Our results suggest that this apparent niche separation within the genus Vibrio may also be influenced by alternate factors such as nutrient levels and high abundances of dinoflagellates. A V. cholerae/V. mimicus population was detected in more than 50% of the samples, with abundances exceeding 10(3) cells liter(-1), even in the cold (annual average water temperature of around 5 degrees C) and low-salinity (2 to 4 per thousand) samples from the Bothnian Bay (latitude, 65 degrees N). The unsuspected and widespread occurrence of this population in temperate and boreal coastal waters suggests that potential Vibrio pathogens may also be endemic to cold and brackish waters and hence may represent a previously overlooked health hazard. PMID:16957222

Eiler, Alexander; Johansson, Mona; Bertilsson, Stefan

2006-09-01

246

Wound infections caused by Vibrio vulnificus and other marine bacteria.  

PubMed Central

Infections caused by Vibrio vulnificus were first reported in 1979 by Blake et al. of the US Centers for Disease Control. At that time described as a 'rare, unnamed halophilic lactose-fermenting Vibrio species', V. vulnificus has emerged as the most virulent foodborne pathogen in the United States with a hospitalization rate of 0.910 and a case-fatality rate of 0.390. It is in addition a significant cause of potentially life-threatening wound infections. Infections following ingestion of raw or undercooked seafood, commonly raw oysters, can lead to a primary septicaemia with a fatality rate of 50-60%. An unusual symptom, occurring in 69% of 274 cases reviewed by Oliver, is the development of secondary lesions, typically on the extremities, which are generally severe (often a necrotizing fasciitis) and require tissue debridement or amputation. These cases occur almost exclusively in males over the age of 50 years. Interestingly, this gender specificity has been found to be due to the female hormone oestrogen, which in some manner provides protection against the lethal V. vulnificus endotoxin. Further, most cases occur in persons with certain underlying diseases which are either immunocompromising or which lead to elevated serum iron levels (e.g. liver cirrhosis, chronic hepatitis, haemochromatosis). V. vulnificus infections resulting in primary septicaemia have been extensively studied, and the subject of several reviews. This review concentrates on the wound infections caused by this marine bacterial pathogen, including the more recently described biotypes 2 and 3, with brief discussions of those caused by other marine vibrios, and the increasingly reported wound/skin infections caused by Mycobacterium marinum, Erysipelothrix rhusiopathiae, and Aeromnonas hydrophila. PMID:15962544

Oliver, J. D.

2005-01-01

247

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

PubMed

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

Olischläger, Mark; Wiencke, Christian

2013-12-01

248

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

PubMed Central

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

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

2011-01-01

249

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

PubMed

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

Wendling, Carolin C; Wegner, K Mathias

2015-04-01

250

Melanization reaction products of shrimp display antimicrobial properties against their major bacterial and fungal pathogens.  

PubMed

Melanization is a rapid defense mechanism in invertebrates. The substrate specificity of phenoloxidases (POs) and the role of melanization reaction products were investigated in the black tiger shrimp, Penaeus monodon. Two PmPOs (PmproPO1 and PmproPO2) were found to display a substrate specificity towards monophenols and diphenols, and exhibit relatively weak activity against 5,6-dihydroxyindole (DHI). Systemic infection of the PmproPO1/2 co-silenced shrimp with the fungus, Fusarium solani, led to a significantly increased mortality, suggesting an important role of PmproPOs in shrimp's defense against fungal infection. Using L-DOPA, dopamine or DHI as a substrate, the melanization reaction products exhibited in vitro antimicrobial activities towards Gram-negative bacteria (Vibrio harveyi and Vibrioparahaemolyticus) and Gram-positive bacteria (Bacillus subtilis), whereas the lower effect was detected against the fungus (F. solani). SEM analysis revealed the morphological changes and damage of cell membranes of V. harveyi and F. solani after treatment with shrimp melanization reaction products. Together, these findings demonstrate the crucial functions of the proPO system and the importance of melanization reaction products in the shrimp's immune defense. PMID:25043262

Charoensapsri, Walaiporn; Amparyup, Piti; Suriyachan, Chawapat; Tassanakajon, Anchalee

2014-11-01

251

Radiofrequency transmission line for bioluminescent Vibrio sp. irradiation  

NASA Astrophysics Data System (ADS)

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

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

2012-07-01

252

Dynamics in genome evolution of Vibrio cholerae.  

PubMed

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

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

2014-04-01

253

Environmental Investigations of Vibrio parahaemolyticus in Oysters after Outbreaks in Washington, Texas, and New York (1997 and 1998)  

Microsoft Academic Search

Total Vibrio parahaemolyticus densities and the occurrence of pathogenic strains in shellfish were determined following outbreaks in Washington, Texas, and New York. Recently developed nonradioactive DNA probes were utilized for the first time for direct enumeration of V. parahaemolyticus in environmental shellfish samples. V. parahaemolyticus was prevalent in oysters from Puget Sound, Wash.; Galveston Bay, Tex.; and Long Island Sound,

ANGELO DEPAOLA; CHARLES A. KAYSNER; JOHN BOWERS; DAVID W. COOK

2000-01-01

254

The haem-uptake gene cluster in Vibrio fischeri is regulated by Fur and contributes to symbiotic  

E-print Network

The haem-uptake gene cluster in Vibrio fischeri is regulated by Fur and contributes to symbiotic that bacteria-colonizing host tissues are commonly faced with iron-limiting condi- tions and that pathogenic bacteria often utilize iron from host-derived haem-based compounds, the mechanisms of iron acquisition

McFall-Ngai, Margaret

255

Vaccination of sex reversed hybrid tilapia (Oreochromis niloticus X O. aureus) with an inactivated Vibrio vulnificus vaccine  

Technology Transfer Automated Retrieval System (TEKTRAN)

Vibrio vulnificus causes disease in economically important aquaculture raised fish and is an opportunistic human pathogen. This study reports on the isolation of V. vulnificus from diseased hybrid tilapia (Oreochromis niloticus X O. aureus) cultured in a North American water reuse facility. Our ob...

256

Loss of sigma factor RpoN increases intestinal colonization of vibrio parahaemolyticus in an adult mouse model"  

Technology Transfer Automated Retrieval System (TEKTRAN)

Vibrio parahaemolyticus is the leading cause of bacterial seafood-borne gastroenteritis worldwide, yet little is known about how this pathogen colonizes the human intestine. The alternative sigma factor RpoN/sigma-54 is a global regulator that controls flagella synthesis as well as a wide range of ...

257

The Vibrio cholerae Colonization Factor GbpA Possesses a Modular Structure that Governs Binding to Different  

E-print Network

-negative bacterial pathogen that causes excessive watery diarrhea in humans [1,2]. The number of reported cases. Bacterial binding studies show that domains 2 and 3 bind to the V. cholerae surface. Finally, mouse Laboratory (EMBL), Outstation Hamburg at DESY, Hamburg, Germany Abstract Vibrio cholerae is a bacterial

van Aalten, Daan

258

Free-living and plankton-associated vibrios: assessment in ballast water, harbor areas, and coastal ecosystems in Brazil.  

PubMed

Ballast water (BW) is a major transport vector of exotic aquatic species and pathogenic microorganisms. The wide-ranging spread of toxigenic Vibrio cholerae O1 from harbor areas has been frequently ascribed to discharge of contaminated BW into eutrophic coastal environments, such as during the onset of the seventh cholera pandemic in South America in the early 1990s. To determine the microbiological hazards of BWs transported to Brazilian ports, we evaluated water and plankton samples taken from (i) BW tanks of recently arrived ships, (ii) port areas along the Brazilian coastline from ?1 to 32°S and (iii) three coastal areas in São Paulo State. Vibrio concentration and toxigenic V. cholerae O1 occurrence were analyzed. Plankton-associated vibrios were more abundant than free-living vibrios in all studied environments. V. cholerae was found in 9.5% of ballast tanks and 24.2% of port samples, both as free-living and attached forms and, apart from the Santos harbor, was absent off São Paulo State. Toxigenic V. cholerae O1 isolates (ctxA(+), tcpA(+)), involved in cholera disease, were found in BW (2%) and harbor (2%) samples. These results confirm that BW is an important carrier of pathogenic organisms, and that monitoring of vibrios and other plankton-attached bacteria is of paramount importance in BW management programs. PMID:23335920

Rivera, Irma N G; Souza, Keili M C; Souza, Claudiana P; Lopes, Rubens M

2012-01-01

259

Free-Living and Plankton-Associated Vibrios: Assessment in Ballast Water, Harbor Areas, and Coastal Ecosystems in Brazil  

PubMed Central

Ballast water (BW) is a major transport vector of exotic aquatic species and pathogenic microorganisms. The wide-ranging spread of toxigenic Vibrio cholerae O1 from harbor areas has been frequently ascribed to discharge of contaminated BW into eutrophic coastal environments, such as during the onset of the seventh cholera pandemic in South America in the early 1990s. To determine the microbiological hazards of BWs transported to Brazilian ports, we evaluated water and plankton samples taken from (i) BW tanks of recently arrived ships, (ii) port areas along the Brazilian coastline from ?1 to 32°S and (iii) three coastal areas in São Paulo State. Vibrio concentration and toxigenic V. cholerae O1 occurrence were analyzed. Plankton-associated vibrios were more abundant than free-living vibrios in all studied environments. V. cholerae was found in 9.5% of ballast tanks and 24.2% of port samples, both as free-living and attached forms and, apart from the Santos harbor, was absent off São Paulo State. Toxigenic V. cholerae O1 isolates (ctxA+, tcpA+), involved in cholera disease, were found in BW (2%) and harbor (2%) samples. These results confirm that BW is an important carrier of pathogenic organisms, and that monitoring of vibrios and other plankton-attached bacteria is of paramount importance in BW management programs. PMID:23335920

Rivera, Irma N. G.; Souza, Keili M. C.; Souza, Claudiana P.; Lopes, Rubens M.

2013-01-01

260

[Characteristics of Vibrio parahaemolyticus isolated from mussels (Perna perna) commercialized at Niterói, Rio de Janeiro].  

PubMed

The marine ecosystem is the natural habitat of bacteria like Vibrio parahaemolyticus, an important pathogen that cause human gastroenteritis associated with seafood consumption. In the present investigation, the presence of V. parahaemolyticus in 86 in natural and precooked mussel samples was evaluated. Vibrio parahaemolyticus was isolated from 11.6% of the in natural and precooked mussels. All strains tested were urease-positive and 28.5% were Kanagawa-positive, which suggests that they have pathogenic potential for humans. There was predominance of the O10:K52 serotype and the emerging O3:K6 strain was identified. These results show the epidemiological relevance of V. parahaemolyticus in cases of human gastroenteritis following mussel consumption without adequately cooking them (100 degrees C/15 min). Moreover, it is important to alert the Brazilian Sanitary Surveillance authorities regarding their presence in the food chain and their public health risks. PMID:17486255

Pereira, Christiane Soares; Possas, Cristina de Albuquerque; Viana, Célio Mauro; Rodrigues, Dália dos Prazeres

2007-01-01

261

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

PubMed Central

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

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

2013-01-01

262

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

Microsoft Academic Search

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

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

2001-01-01

263

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

PubMed

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

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

2015-01-01

264

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

Microsoft Academic Search

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

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

1999-01-01

265

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

Microsoft Academic Search

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

Namiha Yamada; Satoru Suzuki; Eiichiro Tanoue

2000-01-01

266

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

Microsoft Academic Search

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

NAMIHA YAMADA; SATORU SUZUKI; EIICHIRO TANOUE

2000-01-01

267

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

Microsoft Academic Search

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

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

1982-01-01

268

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

PubMed Central

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

Petronella, N.; Kenwell, R.; Banerjee, S.

2015-01-01

269

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

Microsoft Academic Search

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

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

2005-01-01

270

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

PubMed

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

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

2014-09-01

271

Surface Immuno-Functionalisation for the Capture and Detection of Vibrio Species in the Marine Environment: A New Management Tool for Industrial Facilities  

PubMed Central

Bacteria from the genus Vibrio are a common and environmentally important group of bacteria within coastal environments and include species pathogenic to aquaculture organisms. Their distribution and abundance are linked to specific environmental parameters, including temperature, salinity and nutrient enrichment. Accurate and efficient detection of Vibrios in environmental samples provides a potential important indicator of overall ecosystem health while also allowing rapid management responses for species pathogenic to humans or species implicated in disease of economically important aquacultured fish and invertebrates. In this study, we developed a surface immuno-functionalisation protocol, based on an avidin-biotin type covalent binding strategy, allowing specific sandwich-type detection of bacteria from the Vibrio genus. The assay was optimized on 12 diverse Vibrio strains, including species that have implications for aquaculture industries, reaching detection limits between 7×103 to 3×104 cells mL?1. Current techniques for the detection of total Vibrios rely on laborious or inefficient analyses resulting in delayed management decisions. This work represents a novel approach for a rapid, accurate, sensitive and robust tool for quantifying Vibrios directly in industrial systems and in the environment, thereby facilitating rapid management responses. PMID:25310801

Laczka, Olivier F.; Labbate, Maurizio; Seymour, Justin R.; Bourne, David G.; Fielder, Stewart S.; Doblin, Martina A.

2014-01-01

272

Some emerging food and water borne pathogens.  

PubMed

Emerging pathogens are those infective organisms whose incidence has recently increased or is likely to increase during the next two decades due to changes in demography, food habits, food technology, commerce, water sources and environmental factors. Some important emerging food and water borne bacterial pathogens include Listeria monocytogenes, Campylobacter jejuni, Yersinia enterocolitica, Salmonella enteritidis, Escherichia coli O157: H7, Vibrio cholerae biotype E1 Tor Serotype 0139, Vibrio parahaemolyticus and Aeromonas hydrophila, A. sobria, and A. caviae. The prevalence, ecological relationships of these organisms, their transmission through food, water and other environmental sources, and role of their virulent factors in the pathogenesis of infections and their public health significance is discussed in this paper with special reference to the situation in India. PMID:10810592

Gugnani, H C

1999-06-01

273

Molecular analysis of the emergence of pandemic Vibrio parahaemolyticus  

PubMed Central

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

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

2008-01-01

274

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

PubMed Central

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

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

2012-01-01

275

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

PubMed Central

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

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

2008-01-01

276

Vibrio chromosome-specific families  

PubMed Central

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

Lukjancenko, Oksana; Ussery, David W.

2014-01-01

277

Vibrio chromosome-specific families.  

PubMed

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

Lukjancenko, Oksana; Ussery, David W

2014-01-01

278

Incidence of Vibrio species associated with blue crabs (Callinectes sapidus) collected from Galveston Bay, Texas.  

PubMed

Bacteria were readily isolated from the hemolymph of a majority (88%) of the blue crabs collected from Galveston Bay, Texas. The hemolymph of most crabs contained moderate (greater than 10(3) bacteria/ml) to heavy (greater than (10(5) bacteria/ml) infections. Large variances were observed in the bacterial number associated with individual crabs, but no significant difference was observed between the mean bacterial levels in the hemolymph of crabs collected during different seasons of the sampling year. Vibrio spp. were the predominant bacterial types in the hemolymph of infected crabs and increased in number significantly during the summer season. Warmer water temperatures were thought to be responsible for this increase. Bacterial numbers and the percentage of Vibrio spp. were highest in the interior of the crab bodies, especially in the digestive tract. The exterior of the crabs did not appear to be the source of the hemolymph's bacterial flora. Bacteria taxonomically identical to Vibrio cholerae. V. vulnificus, and V. parahaemolyticus were routinely isolated from the crab hemolymph and external carapace. V. parahaemolyticus was the most prevalent of the pathogenic Vibrio spp. and was isolated from 23% of the hemolymph samples. V. vulnificus (7%) and V. cholerae (2%) occurred less commonly in the hemolymph. The incidences of V. parachaemolyticus and V. vulnificus were related and increased in the summer months. Both organisms were frequently isolated from the same crab. PMID:7103475

Davis, J W; Sizemore, R K

1982-05-01

279

Incidence of Vibrio species associated with blue crabs (Callinectes sapidus) collected from Galveston Bay, Texas.  

PubMed Central

Bacteria were readily isolated from the hemolymph of a majority (88%) of the blue crabs collected from Galveston Bay, Texas. The hemolymph of most crabs contained moderate (greater than 10(3) bacteria/ml) to heavy (greater than (10(5) bacteria/ml) infections. Large variances were observed in the bacterial number associated with individual crabs, but no significant difference was observed between the mean bacterial levels in the hemolymph of crabs collected during different seasons of the sampling year. Vibrio spp. were the predominant bacterial types in the hemolymph of infected crabs and increased in number significantly during the summer season. Warmer water temperatures were thought to be responsible for this increase. Bacterial numbers and the percentage of Vibrio spp. were highest in the interior of the crab bodies, especially in the digestive tract. The exterior of the crabs did not appear to be the source of the hemolymph's bacterial flora. Bacteria taxonomically identical to Vibrio cholerae. V. vulnificus, and V. parahaemolyticus were routinely isolated from the crab hemolymph and external carapace. V. parahaemolyticus was the most prevalent of the pathogenic Vibrio spp. and was isolated from 23% of the hemolymph samples. V. vulnificus (7%) and V. cholerae (2%) occurred less commonly in the hemolymph. The incidences of V. parachaemolyticus and V. vulnificus were related and increased in the summer months. Both organisms were frequently isolated from the same crab. PMID:7103475

Davis, J W; Sizemore, R K

1982-01-01

280

Vibrio cholerae Represses Polysaccharide Synthesis To Promote Motility in Mucosa.  

PubMed

The viscoelastic mucus layer of gastrointestinal tracts is a host defense barrier that a successful enteric pathogen, such as Vibrio cholerae, must circumvent. V. cholerae, the causative agent of cholera, is able to penetrate the mucosa and colonize the epithelial surface of the small intestine. In this study, we found that mucin, the major component of mucus, promoted V. cholerae movement on semisolid medium and in liquid medium. A genome-wide screen revealed that Vibrio polysaccharide (VPS) production was inversely correlated with mucin-enhanced motility. Mucin adhesion assays indicated that VPS bound to mucin. Moreover, we found that vps expression was reduced upon exposure to mucin. In an infant mouse colonization model, mutants that overexpressed VPS colonized less effectively than wild-type strains in more distal intestinal regions. These results suggest that V. cholerae is able to sense mucosal signals and modulate vps expression accordingly so as to promote fast motion in mucus, thus allowing for rapid spread throughout the intestines. PMID:25561707

Liu, Zhenyu; Wang, Yuning; Liu, Shengyan; Sheng, Ying; Rueggeberg, Karl-Gustav; Wang, Hui; Li, Jie; Gu, Frank X; Zhong, Zengtao; Kan, Biao; Zhu, Jun

2015-03-01

281

Comparative genomic analysis of Vibrio parahaemolyticus: serotype conversion and virulence  

PubMed Central

Background Vibrio parahaemolyticus is a common cause of foodborne disease. Beginning in 1996, a more virulent strain having serotype O3:K6 caused major outbreaks in India and other parts of the world, resulting in the emergence of a pandemic. Other serovariants of this strain emerged during its dissemination and together with the original O3:K6 were termed strains of the pandemic clone. Two genomes, one of this virulent strain and one pre-pandemic strain have been sequenced. We sequenced four additional genomes of V. parahaemolyticus in this study that were isolated from different geographical regions and time points. Comparative genomic analyses of six strains of V. parahaemolyticus isolated from Asia and Peru were performed in order to advance knowledge concerning the evolution of V. parahaemolyticus; specifically, the genetic changes contributing to serotype conversion and virulence. Two pre-pandemic strains and three pandemic strains, isolated from different geographical regions, were serotype O3:K6 and either toxin profiles (tdh+, trh-) or (tdh-, trh+). The sixth pandemic strain sequenced in this study was serotype O4:K68. Results Genomic analyses revealed that the trh+ and tdh+ strains had different types of pathogenicity islands and mobile elements as well as major structural differences between the tdh pathogenicity islands of the pre-pandemic and pandemic strains. In addition, the results of single nucleotide polymorphism (SNP) analysis showed that 94% of the SNPs between O3:K6 and O4:K68 pandemic isolates were within a 141 kb region surrounding the O- and K-antigen-encoding gene clusters. The "core" genes of V. parahaemolyticus were also compared to those of V. cholerae and V. vulnificus, in order to delineate differences between these three pathogenic species. Approximately one-half (49-59%) of each species' core genes were conserved in all three species, and 14-24% of the core genes were species-specific and in different functional categories. Conclusions Our data support the idea that the pandemic strains are closely related and that recent South American outbreaks of foodborne disease caused by V. parahaemolyticus are closely linked to outbreaks in India. Serotype conversion from O3:K6 to O4:K68 was likely due to a recombination event involving a region much larger than the O-antigen- and K-antigen-encoding gene clusters. Major differences between pathogenicity islands and mobile elements are also likely driving the evolution of V. parahaemolyticus. In addition, our analyses categorized genes that may be useful in differentiating pathogenic Vibrios at the species level. PMID:21645368

2011-01-01

282

Primary Vibrio vulnificus sepsis in Kentucky.  

PubMed

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

Ali, M B; Raff, M J

1990-03-01

283

Temporal Quorum-Sensing Induction Regulates Vibrio cholerae Biofilm Architecture?  

PubMed Central

Vibrio cholerae, the pathogen that causes cholera, also survives in aqueous reservoirs, probably in the form of biofilms. Quorum sensing negatively regulates V. cholerae biofilm formation through HapR, whose expression is induced at a high cell density. In this study, we show that the concentration of the quorum-sensing signal molecule CAI-1 is higher in biofilms than in planktonic cultures. By measuring hapR expression and activity, we found that the induction of quorum sensing in biofilm-associated cells occurs earlier. We further demonstrate that the timing of hapR expression is crucial for biofilm thickness, biofilm detachment rates, and intestinal colonization efficiency. These results suggest that V. cholerae is able to regulate its biofilm architecture by temporal induction of quorum-sensing systems. PMID:17074850

Liu, Zhi; Stirling, Fiona R.; Zhu, Jun

2007-01-01

284

Phage Therapy as an Approach to Prevent Vibrio anguillarum Infections in Fish Larvae Production  

PubMed Central

Fish larvae in aquaculture have high mortality rates due to pathogenic bacteria, especially the Vibrio species, and ineffective prophylactic strategies. Vaccination is not feasible in larvae and antibiotics have reduced efficacy against multidrug resistant bacteria. A novel approach to controlling Vibrio infections in aquaculture is needed. The potential of phage therapy to combat vibriosis in fish larvae production has not yet been examined. We describe the isolation and characterization of two bacteriophages capable of infecting pathogenic Vibrio and their application to prevent bacterial infection in fish larvae. Two groups of zebrafish larvae were infected with V. anguillarum (?106 CFU mL?1) and one was later treated with a phage lysate (?108 PFU mL?1). A third group was only added with phages. A fourth group received neither bacteria nor phages (fish control). Larvae mortality, after 72 h, in the infected and treated group was similar to normal levels and significantly lower than that of the infected but not treated group, indicating that phage treatment was effective. Thus, directly supplying phages to the culture water could be an effective and inexpensive approach toward reducing the negative impact of vibriosis in larviculture. PMID:25464504

Silva, Yolanda J.; Costa, Liliana; Pereira, Carla; Mateus, Cristiana; Cunha, Ângela; Calado, Ricardo; Gomes, Newton C. M.; Pardo, Miguel A.; Hernandez, Igor; Almeida, Adelaide

2014-01-01

285

Physiological responses of the scleractinian coral Pocillopora damicornis to bacterial stress from Vibrio coralliilyticus.  

PubMed

As the effects of climate change have become increasingly visible over the past three decades, coral reefs have suffered from a number of natural and anthropogenic disturbances that have caused a critical decline in coral populations. Among these disturbances are coral diseases, which have appeared with increasing frequency and severity, often in correlation with increases in water temperature. Although the crucial role played by Vibrio species in coral disease has been widely documented, the scientific community does not yet fully understand the infection process of Vibrio or its impact on coral physiology and immunology. Here, we investigated the physiological and transcriptomic responses of a major reef-building coral, Pocillopora damicornis, when exposed to a specific pathogen (Vibrio coralliilyticus) under virulent (increasing water temperature) and non-virulent (constant low temperature) conditions. The infection process was examined by electron microscopy and quantitative reverse-transcription PCR, and coral health was monitored by visual observations and measurements of zooxanthellar density. The results obtained suggest that coral tissue invasion occurs upon increasing water temperature only. Transcriptomic variations were investigated using a suppression-subtractive-hybridization approach, and the expression levels of six candidate immune-related genes were examined during bacterial exposure. These genes correspond to three lectin-like molecules putatively involved in the recognition of pathogens, two metal-binding proteins putatively involved in antibacterial response and one cystein protease inhibitor. The transcription patterns of these selected genes provide new insights into the responses of coral colonies to virulent versus non-virulent bacteria. PMID:21490261

Vidal-Dupiol, Jeremie; Ladrière, Ophélie; Meistertzheim, Anne-Leila; Fouré, Laurent; Adjeroud, Mehdi; Mitta, Guillaume

2011-05-01

286

Vibrio chromosomes share common history  

PubMed Central

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

2010-01-01

287

Lessons from cholera & Vibrio cholerae  

PubMed Central

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

Ghose, Asoke C.

2011-01-01

288

VIBRIO VULNIFICUS EDUCATION WORKSHOP FOR THE FLORIDA MEDICAL COMMUNITY  

EPA Science Inventory

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

289

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

NASA Astrophysics Data System (ADS)

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.

Yuan, Ye; Wang, Xiuli; Guo, Sheping; Liu, Yang; Ge, Hui; Qiu, Xuemei

2010-11-01

290

Siderocalin outwits the coordination chemistry of vibriobactin, a siderophore of Vibrio cholerae  

PubMed Central

The human protein siderocalin (Scn) inhibits bacterial iron acquisition by binding catechol siderophores. Several pathogenic bacteria respond by making stealth siderophores that are not recognized by Scn. Fluvibactin and vibriobactin, respectively of Vibrio fluvialis and Vibrio cholerae, include an oxazoline adjacent to a catechol. This chelating unit binds iron either in a catecholate or a phenolate oxazoline coordination mode. The latter has been suggested to make vibriobactin a stealth siderophore without directly identifying the coordination mode in relation to Scn binding. We use Scn binding assays with the two siderophores and two oxazoline substituted analogs and the crystal structure of Fe fluvibactin:Scn to show that the oxazoline does not prevent Scn binding; hence, vibriobactin is not a stealth siderophore. We show that the phenolate oxazoline coordination mode is present at physiological pH and is not bound by Scn. However, Scn binding shifts the coordination to the catecholate mode and thereby inactivates this siderophore. PMID:23755875

Allred, Benjamin E.; Correnti, Colin; Clifton, Matthew C.; Strong, Roland K.; Raymond, Kenneth N.

2013-01-01

291

Siderocalin outwits the coordination chemistry of vibriobactin, a siderophore of Vibrio cholerae.  

PubMed

The human protein siderocalin (Scn) inhibits bacterial iron acquisition by binding catechol siderophores. Several pathogenic bacteria respond by making stealth siderophores that are not recognized by Scn. Fluvibactin and vibriobactin, respectively of Vibrio fluvialis and Vibrio cholerae , include an oxazoline adjacent to a catechol. This chelating unit binds iron either in a catecholate or a phenolate-oxazoline coordination mode. The latter has been suggested to make vibriobactin a stealth siderophore without directly identifying the coordination mode in relation to Scn binding. We use Scn binding assays with the two siderophores and two oxazoline-substituted analogs and the crystal structure of Fe-fluvibactin:Scn to show that the oxazoline does not prevent Scn binding; hence, vibriobactin is not a stealth siderophore. We show that the phenolate-oxazoline coordination mode is present at physiological pH and is not bound by Scn. However, Scn binding shifts the coordination to the catecholate mode and thereby inactivates this siderophore. PMID:23755875

Allred, Benjamin E; Correnti, Colin; Clifton, Matthew C; Strong, Roland K; Raymond, Kenneth N

2013-09-20

292

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

PubMed Central

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

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

2007-01-01

293

Adsorption and growth of Vibrio cholerae on chitin.  

PubMed Central

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

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

1979-01-01

294

Cloning and Characterization of an Outer Membrane Protein of Vibrio vulnificus Required for Heme Utilization: Regulation of Expression and Determination of the Gene Sequence  

Microsoft Academic Search

Vibrio vulnificus is a halophilic, marine pathogen that has been associated with septicemia and serious wound infections in patients with iron overload and preexisting liver disease. For V. vulnificus, the ability to acquire iron from the host has been shown to correlate with virulence. V. vulnificus is able to use host iron sources such as hemoglobin and heme. We previously

CHRISTINE M. LITWIN; BURKE L. BYRNE

1998-01-01

295

Draft Genome Sequence of Vibrio owensii GRA50-12, Isolated from Green Algae in the Intertidal Zone of Eastern Taiwan  

PubMed Central

Vibrio owensii GRA50-12 was isolated from symbiotic green algae of coral. The genome contains genes encoding toxin production, virulence regulation, stress response proteins, types II, IV, and VI secretion systems, and proteins for the metabolism of aromatic compounds, which reflects its pathogenic potential and its ecological roles in the ocean. PMID:25593265

Lin, Ling-Chun; Lin, Guang-Huey

2015-01-01

296

Development of a two-step, multiplex SYBR green quantitative PCR (MSG qPCR)assay for the rapid detection of vibrio anguillarum from seawater  

Technology Transfer Automated Retrieval System (TEKTRAN)

Vibrio anguillarum is an aggressive and halophilic bacterial pathogen commonly found in seawater. Its presence in aquaculture facilities causes significant morbidity and mortality among aquaculture species primarily from hemorrhaging of the body and skin of the infected fish that eventually leads t...

297

Draft Genome Sequence of Vibrio owensii GRA50-12, Isolated from Green Algae in the Intertidal Zone of Eastern Taiwan.  

PubMed

Vibrio owensii GRA50-12 was isolated from symbiotic green algae of coral. The genome contains genes encoding toxin production, virulence regulation, stress response proteins, types II, IV, and VI secretion systems, and proteins for the metabolism of aromatic compounds, which reflects its pathogenic potential and its ecological roles in the ocean. PMID:25593265

Lin, Ling-Chun; Lin, Guang-Huey; Tseng, Yi-Hsiung; Yu, Mei-Shiuan

2015-01-01

298

Quorum-quenching activity of the AHL-lactonase from Bacillus licheniformis DAHB1 inhibits vibrio biofilm formation in vitro and reduces shrimp intestinal colonisation and mortality.  

PubMed

Vibrio parahaemolyticus is a significant cause of gastroenteritis resulting from the consumption of undercooked sea foods and often cause significant infections in shrimp aquaculture. Vibrio virulence is associated with biofilm formation and is regulated by N-acylated homoserine lactone (AHL)-mediated quorum sensing. In an attempt to reduce vibrio colonisation of shrimps and mortality, we screened native intestinal bacilli from Indian white shrimps (Fenneropenaeus indicus) for an isolate which showed biofilm-inhibitory activity (quorum quenching) against the pathogen V. parahaemolyticus DAHP1. The AHL-lactonase (AiiA) expressed by one of these, Bacillus licheniformis DAHB1, was characterised as having a broad-spectrum AHL substrate specificity and intrinsic resistance to the acid conditions of the shrimp intestine. Purified recombinant AiiA inhibited vibrio biofilm development in a cover slip assay and significantly attenuated infection and mortality in shrimps reared in a recirculation aquaculture system. Investigation of intestinal samples also showed that AiiA treatment also reduced vibrio viable counts and biofilm development as determined by confocal laser scanning microscopy (CLSM) imaging. These findings suggest that the B. licheniformis DAHB1 quorum-quenching AiiA might be developed for use as a prophylactic treatment to inhibit or reduce vibrio colonisation and mortality of shrimps in aquaculture. PMID:25060960

Vinoj, G; Vaseeharan, B; Thomas, S; Spiers, A J; Shanthi, S

2014-12-01

299

Control of luminous Vibrio species in penaeid aquaculture ponds  

Microsoft Academic Search

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

D. J. W Moriarty

1998-01-01

300

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

PubMed

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

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

2014-01-01

301

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

PubMed Central

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

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

2014-01-01

302

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

PubMed

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

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

2010-01-01

303

Role of DnaK in In Vitro and In Vivo Expression of Virulence Factors of Vibrio cholerae  

Microsoft Academic Search

The dnaK gene of Vibrio cholerae was cloned, sequenced, and used to construct a dnaK insertion mutant which was then used to examine the role of DnaK in expression of the major virulence factors of this important human pathogen. The central regulator of several virulence genes of V. cholerae is ToxR, a transmembrane DNA binding protein. The V. cholerae dnaK

SABYASACHI CHAKRABARTI; NILANJAN SENGUPTA; RUKHSANA CHOWDHURY

1999-01-01

304

Genome assortment, not serogroup, defines Vibrio cholerae pandemic strains  

SciTech Connect

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

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

2009-01-01

305

Cholera and other vibrio-associated diarrhoeas*  

PubMed Central

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

1980-01-01

306

Vibrio aestuarianus zinc metalloprotease causes lethality in the Pacific oyster Crassostrea gigas and impairs the host cellular immune defenses.  

PubMed

Extracellular products (ECPs) of the pathogenic Vibrio aestuarianus 01/32 were previously reported to display lethality in Crassostrea gigas oysters and to cause morphological changes and immunosuppression in oyster hemocytes. To identify the source of this toxicity, biochemical and genetic approaches were developed. ECP protease activity and lethality were shown to be significantly reduced following incubation with metal chelators, suggesting the involvement of a zinc metalloprotease. An open reading frame of 1836 bp encoding a 611-aa metalloprotease (designated Vam) was identified. The deduced protein sequence showed high homology to other Vibrio metalloproteases reported to be involved in pathogenicity. To further confirm the role of this enzyme in ECP toxicity, a plasmid carrying the vam gene under the control of an araC-P(BAD) expression cassette was transferred to a Vibrio splendidus related strain, LMG20012(T), previously characterized as non-pathogenic to oysters. Expression of Vam conferred a toxic phenotype to LMG20012(T) ECPs in vivo and cytotoxicity to oyster hemocytes in vitro. Collectively, these data suggest that the Vam metalloprotease is a major contributor to the toxicity induced by V. aestuarianus ECPs and is involved in the impairment of oyster hemocyte functions. PMID:20624467

Labreuche, Yannick; Le Roux, Frédérique; Henry, Joël; Zatylny, Céline; Huvet, Arnaud; Lambert, Christophe; Soudant, Philippe; Mazel, Didier; Nicolas, Jean-Louis

2010-11-01

307

A model for Vibrio cholerae colonization of the human intestine  

PubMed Central

Vibrio cholerae is a strict human pathogen that causes the disease cholera. It is an old-world pathogen that has re-emerged as a new threat since the early 1990s. V. cholerae colonizes the upper, small intestine where it produces a toxin that leads to watery diarrhea, characterizing the disease [36]. The dynamics of colonization by the bacteria of the intestines are largely unknown. Although a large initial infectious dose is required for infection, data suggests that only a smaller sub-population colonizes a portion of the small bowel leading to disease. There are many barriers to colonization in the intestines including peristalsis, fluid wash-out, viscosity of the mucus layer, and pH. We are interested in identifying the mechanisms that allow this sub-population of bacteria to survive and colonize the intestines when faced with these barriers. To elaborate the dynamics of V. cholerae infection, we have developed a mathematical model based on a convection-diffusion-reaction-swimming equation capturing bacterial dynamics coupled with Stokes equations governing fluid velocity where we developed a novel non-local boundary condition. Our results indicate that both host and bacterial factors contribute to bacterial density in the gut. Host factors include intestinal diffusion and convection rates while bacterial factors include adherence, motility and growth rates. This model can ultimately be used to test therapeutic strategies against V. cholerae. PMID:21903104

Spagnuolo, Anna Maria; DiRita, Victor; Kirschner, Denise

2011-01-01

308

?-Hydroxyketone Synthesis and Sensing by Legionella and Vibrio  

PubMed Central

Bacteria synthesize and sense low molecular weight signaling molecules, termed autoinducers, to measure their population density and community complexity. One class of autoinducers, the ?-hydroxyketones (AHKs), is produced and detected by the water-borne opportunistic pathogens Legionella pneumophila and Vibrio cholerae, which cause Legionnaires’ disease and cholera, respectively. The “Legionella quorum sensing” (lqs) or “cholera quorum sensing” (cqs) genes encode enzymes that produce and sense the AHK molecules “Legionella autoinducer-1” (LAI-1; 3-hydroxypentadecane-4-one) or cholera autoinducer-1 (CAI-1; 3-hydroxytridecane-4-one). AHK signaling regulates the virulence of L. pneumophila and V. cholerae, pathogen-host cell interactions, formation of biofilms or extracellular filaments, expression of a genomic “fitness island” and competence. Here, we outline the processes, wherein AHK signaling plays a role, and review recent insights into the function of proteins encoded by the lqs and cqs gene clusters. To this end, we will focus on the autoinducer synthases catalysing the biosynthesis of AHKs, on the cognate trans-membrane sensor kinases detecting the signals, and on components of the down-stream phosphorelay cascade that promote the transmission and integration of signaling events regulating gene expression. PMID:22736983

Tiaden, André; Hilbi, Hubert

2012-01-01

309

The pathogenesis, detection, and prevention of Vibrio parahaemolyticus  

PubMed Central

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

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

2015-01-01

310

Genetic characterization of trh positive Vibrio spp. isolated from Norway.  

PubMed

The thermostable direct hemolysin (TDH) and/or TDH-related hemolysin (TRH) genes are carried by most virulent Vibrio parahaemolyticus serovars. In Norway, trh+ V. parahaemolyticus constitute 4.4 and 4.5% of the total number of V. parahaemolyticus isolated from blue mussel (Mytilus edulis) and water, respectively. The trh gene is located in a region close to the gene cluster for urease production (ure). This region was characterized in V. parahaemolyticus strain TH3996 and it was found that a nickel transport operon (nik) was located between the first gene (ureR) and the rest of the ure cluster genes. The organization of the trh-ureR-nik-ure gene cluster in the Norwegian trh+ isolates was unknown. In this study, we explore the gene organization within the trh-ureR-nik-ure cluster for these isolates. PCR analyses revealed that the genes within the trh-ureR-nik-ure gene cluster of Norwegian trh+ isolates were organized in a similar fashion as reported previously for TH33996. Additionally, the phylogenetic relationship among these trh+ isolates was investigated using Multilocus Sequence Typing (MLST). Analysis by MLST or ureR-trh sequences generated two different phylogenetic trees for the same strains analyzed, suggesting that ureR-trh genes have been acquired at different times in Norwegian V. parahaemolyticus isolates. MLST results revealed that some pathogenic and non-pathogenic V. parahaemolyticus isolates in Norway appear to be highly genetically related. PMID:24400227

Ellingsen, Anette B; Olsen, Jaran S; Granum, Per E; Rørvik, Liv M; González-Escalona, Narjol

2013-01-01

311

Genetic characterization of trh positive Vibrio spp. isolated from Norway  

PubMed Central

The thermostable direct hemolysin (TDH) and/or TDH-related hemolysin (TRH) genes are carried by most virulent Vibrio parahaemolyticus serovars. In Norway, trh+ V. parahaemolyticus constitute 4.4 and 4.5% of the total number of V. parahaemolyticus isolated from blue mussel (Mytilus edulis) and water, respectively. The trh gene is located in a region close to the gene cluster for urease production (ure). This region was characterized in V. parahaemolyticus strain TH3996 and it was found that a nickel transport operon (nik) was located between the first gene (ureR) and the rest of the ure cluster genes. The organization of the trh-ureR-nik-ure gene cluster in the Norwegian trh+ isolates was unknown. In this study, we explore the gene organization within the trh-ureR-nik-ure cluster for these isolates. PCR analyses revealed that the genes within the trh-ureR-nik-ure gene cluster of Norwegian trh+ isolates were organized in a similar fashion as reported previously for TH33996. Additionally, the phylogenetic relationship among these trh+ isolates was investigated using Multilocus Sequence Typing (MLST). Analysis by MLST or ureR-trh sequences generated two different phylogenetic trees for the same strains analyzed, suggesting that ureR-trh genes have been acquired at different times in Norwegian V. parahaemolyticus isolates. MLST results revealed that some pathogenic and non-pathogenic V. parahaemolyticus isolates in Norway appear to be highly genetically related. PMID:24400227

Ellingsen, Anette B.; Olsen, Jaran S.; Granum, Per E.; Rørvik, Liv M.; González-Escalona, Narjol

2013-01-01

312

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

Microsoft Academic Search

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

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

1999-01-01

313

Subversion of inflammasome activation and pyroptosis by pathogenic bacteria  

PubMed Central

Activation of the inflammasome occurs in response to a notably high number of pathogenic microbes and is a broad innate immune response that effectively contributes to restriction of pathogen replication and generation of adaptive immunity. Activation of these platforms leads to caspase-1- and/or caspase-11-dependent secretion of proteins, including cytokines, and induction of a specific form of cell death called pyroptosis, which directly or indirectly contribute for restriction of pathogen replication. Not surprisingly, bona fide intracellular pathogens developed strategies for manipulation of cell death to guarantee intracellular replication. In this sense, the remarkable advances in the knowledge of the inflammasome field have been accompanied by several reports characterizing the inhibition of this platform by several pathogenic bacteria. Herein, we review some processes used by pathogenic bacteria, including Yersinia spp., Pseudomonas aeruginosa, Vibrio parahaemolyticus, Chlamydia trachomatis, Francisella tularensis, Shigella flexneri, Legionella pneumophila, and Coxiella burnetii to evade the activation of the inflammasome and the induction of pyroptosis. PMID:24324933

Cunha, Larissa D.; Zamboni, Dario S.

2013-01-01

314

Microbial experimental evolution as a novel research approach in the Vibrionaceae and squid-Vibrio symbiosis  

PubMed Central

The Vibrionaceae are a genetically and metabolically diverse family living in aquatic habitats with a great propensity toward developing interactions with eukaryotic microbial and multicellular hosts (as either commensals, pathogens, and mutualists). The Vibrionaceae frequently possess a life history cycle where bacteria are attached to a host in one phase and then another where they are free from their host as either part of the bacterioplankton or adhered to solid substrates such as marine sediment, riverbeds, lakebeds, or floating particulate debris. These two stages in their life history exert quite distinct and separate selection pressures. When bound to solid substrates or to host cells, the Vibrionaceae can also exist as complex biofilms. The association between bioluminescent Vibrio spp. and sepiolid squids (Cephalopoda: Sepiolidae) is an experimentally tractable model to study bacteria and animal host interactions, since the symbionts and squid hosts can be maintained in the laboratory independently of one another. The bacteria can be grown in pure culture and the squid hosts raised gnotobiotically with sterile light organs. The partnership between free-living Vibrio symbionts and axenic squid hatchlings emerging from eggs must be renewed every generation of the cephalopod host. Thus, symbiotic bacteria and animal host can each be studied alone and together in union. Despite virtues provided by the Vibrionaceae and sepiolid squid-Vibrio symbiosis, these assets to evolutionary biology have yet to be fully utilized for microbial experimental evolution. Experimental evolution studies already completed are reviewed, along with exploratory topics for future study. PMID:25538686

Soto, William; Nishiguchi, Michele K.

2014-01-01

315

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

PubMed Central

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

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

2013-01-01

316

Isolation of Vibrio alginolyticus from seawater aquaria  

Microsoft Academic Search

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

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

2000-01-01

317

EFFECT OF AGGREGATION ON VIBRIO CHOLERAE INACTIVATION  

EPA Science Inventory

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

318

Preventing maritime transfer of toxigenic Vibrio cholerae.  

PubMed

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

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

2012-10-01

319

Preventing Maritime Transfer of Toxigenic Vibrio cholerae  

PubMed Central

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

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

2012-01-01

320

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

PubMed Central

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

Hasegawa, Hiroaki; Häse, Claudia C.

2009-01-01

321

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

PubMed

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

Hasegawa, Hiroaki; Häse, Claudia C

2009-12-01

322

Emerging water-borne pathogens.  

PubMed

Emerging water-borne pathogens constitute a major health hazard in both developed and developing nations. A new dimension to the global epidemiology of cholera-an ancient scourge-was provided by the emergence of Vibrio cholerae O139. Also, water-borne enterohaemorrhagic Escherichia coli ( E. coli O157:H7), although regarded as a problem of the industrialized west, has recently caused outbreaks in Africa. Outbreaks of chlorine-resistant Cryptosporidium have motivated water authorities to reassess the adequacy of current water-quality regulations. Of late, a host of other organisms, such as hepatitis viruses (including hepatitis E virus), Campylobacter jejuni, microsporidia, cyclospora, Yersinia enterocolitica, calciviruses and environmental bacteria like Mycobacterium spp, aeromonads, Legionella pneumophila and multidrug-resistant Pseudomonas aeruginosa have been associated with water-borne illnesses. This review critically examines the potential of these as emerging water-borne pathogens. It also examines the possible reasons, such as an increase in the number of immunocompromised individuals, urbanization and horizontal gene transfer, that may underlie their emergence. Further, measures required to face the challenge posed by these pathogens are also discussed. PMID:12684849

Sharma, S; Sachdeva, P; Virdi, J S

2003-06-01

323

Molecular Mechanisms of Bacterial Pathogenicity  

NASA Astrophysics Data System (ADS)

Cautious optimism has arisen over recent decades with respect to the long struggle against bacteria, viruses, and parasites. This has been offset, however, by a fatal complacency stemming from previous successes such as the development of antimicrobial drugs, the eradication of smallpox, and global immunization programs. Infectious diseases nevertheless remain the world's leading cause of death, killing at least 17 million persons annually [61]. Diarrheal diseases caused by Vibrio cholerae or Shigella dysenteriae kill about 3 million persons every year, most of them young children: Another 4 million die of tuberculosis or tetanus. Outbreaks of diphtheria in Eastern Europe threatens the population with a disease that had previously seemed to be overcome. Efforts to control infectious diseases more comprehensively are undermined not only by socioeconomic conditions but also by the nature of the pathogenic organisms itself; some isolates of Staphylococcus aureus and Enterobacter have become so resistant to drugs by horizontal gene transfer that they are almost untreatable. In addition, the mechanism of genetic variability helps pathogens to evade the human immune system, thus compromising the development of powerful vaccines. Therefore detailed knowledge of the molecular mechanisms of microbial pathogenicity is absolutely necessary to develop new strategies against infectious diseases and thus to lower their impact on human health and social development.

Fuchs, Thilo Martin

324

The mosaic accessory gene structures of the SXT/R391-like integrative and conjugative elements derived from Vibrio spp. isolated from aquatic products and environment in the Yangtze River estuary, China  

PubMed Central

Background The emergence, resurgence and spread of human food-borne pathogenic Vibrios are one of the major contributors to disease burden and mortality particularly in developing countries with disputable sanitary conditions. Previous research on pathogenic Vibrio cholerae and Vibrio parahaemolitycus derived from clinical samples has proposed links between acquisition of virulence and multiple drug resistance traits and intercellular transmissibility of mobile genetic elements in the environment. To date, very few information is available on environmental Vibrio isolates. In this study, we characterized eleven Vibrio strains bearing the SXT/R391-like integrative and conjugative elements (ICEs) derived from aquatic products and environment in the Yangtze River Estuary, China. Results The eleven Vibrio strains were isolated in 2010 to 2011, and taxonomically identified, which included six Vibrio cholerae, three Vibrio parahaemolyticus, one Vibrio alginolyticus and one Vibrio natriegens. Most of the strains displayed strong resistance phenotypes to ampicillin, mercury and chromium. The majority of their ICEs, which belong to S and R exclusion system groups, contain ICEs-chromosome junction sequences and highly conserved core-genes required for ICE transfer. However, comparative sequence analysis uncovered interesting diversity in their mosaic accessory gene structures, which carry many novel genes that have not been described in any known ICEs to date. In addition, antibiotic resistance was transmitted by ICEVchChn6 and ICEVpaChn1 from V. cholerae, V. parahaemolyticus to E. coli MG1655 via conjugation, respectively. Our data also revealed that the ICEs characterized in this study are phylogenetically distant from most of the SXT/R391 ICEs reported previously, which may represent a novel cluster likely shaped by the ecological environment in the Yangtze River Estuary, China. Conclusions This study constitutes the first investigation of ICEs-positive Vibrio spp. in the Yangze River Estuary, China. The newly identified ICEs were characterized with mosaic accessory gene structures and many novel genes. The results demonstrated self-transmissibility of antibiotic resistance mediated by two of the ICEs from V. cholerae, V. parahaemolyticus to E. coli via conjugation, respectively. Our results also revealed that the ICEs examined in this study may represent a novel cluster in the SXT/R391 family. PMID:24074349

2013-01-01

325

Glycan specificity of the Vibrio vulnificus hemolysin lectin outlines evolutionary history of membrane targeting by a toxin family.  

PubMed

Pore-forming toxins (PFTs) are a class of pathogen-secreted molecules that oligomerize to form transmembrane channels in cellular membranes. Determining the mechanism for how PFTs bind membranes is important in understanding their role in disease and for developing possible ways to block their action. Vibrio vulnificus, an aquatic pathogen responsible for severe food poisoning and septicemia in humans, secretes a PFT called V. vulnificus hemolysin (VVH), which contains a single C-terminal targeting domain predicted to resemble a ?-trefoil lectin fold. In order to understand the selectivity of the lectin for glycan motifs, we expressed the isolated VVH ?-trefoil domain and used glycan-chip screening to identify that VVH displays a preference for terminal galactosyl groups including N-acetyl-d-galactosamine and N-acetyl-d-lactosamine. The X-ray crystal structure of the VVH lectin domain solved to 2.0Å resolution reveals a heptameric ring arrangement similar to the oligomeric form of the related, but inactive, lectin from Vibrio cholerae cytolysin. Structures bound to glycerol, N-acetyl-d-galactosamine, and N-acetyl-d-lactosamine outline a common and versatile mode of recognition allowing VVH to target a wide variety of cell-surface ligands. Sequence analysis in light of our structural and functional data suggests that VVH may represent an earlier step in the evolution of Vibrio PFTs. PMID:24862282

Kaus, Katherine; Lary, Jeffrey W; Cole, James L; Olson, Rich

2014-07-29

326

Transformation Experiment Using Bioluminescence Genes of "Vibrio fischeri."  

ERIC Educational Resources Information Center

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

Slock, James

1995-01-01

327

Applied studies on the viability of El Tor vibrios*  

PubMed Central

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

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

1967-01-01

328

21 CFR 866.3930 - Vibrio cholerae serological reagents.  

Code of Federal Regulations, 2013 CFR

... 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....

2013-04-01

329

Temperature effect on high salinity depuration of Vibrio vulnificus and V. parahaemolyticus from the Eastern oyster (Crassostrea virginica).  

PubMed

Vibrio vulnificus (Vv) and Vibrio parahaemolyticus (Vp) are opportunistic human pathogens naturally associated with the Eastern oyster Crassostrea virginica. The abundances of both pathogens in oysters are positively correlated with temperature, thus ingestion of raw oysters during the warm summer months is a risk factor for contracting illness from these bacteria. Current post-harvest processing (PHP) methods for elimination of these pathogens are expensive and kill the oyster, changing their organoleptic properties and making them less appealing to some consumers. High salinity has proven effective in reducing Vv numbers in the wild and our research aims at developing an indoor recirculating system to reduce pathogenic Vibrios while maintaining the taste and texture of live oysters. The goal of this study was to determine the influence of temperature on the efficacy of high salinity depuration. Vv was enumerated as most probable number (MPN) per gram of oyster tissue using the FDA-approved modified cellobiose polymyxin colistin (mCPC) protocol and with an alternative Vibrio specific media CHROMagar™ Vibrio (CaV). CaV was also used to quantify Vp. Oysters were held at 35 psu for 10 days at three temperatures: low (20°C), mid (22.5°C) and high (25°C). There was no difference in MPN/g of Vv between media; however more Vv isolates were obtained from mCPC than CaV. There was no significant effect of temperature on reduction of Vv or Vp throughout depuration but there was a tendency for low temperatures to be less effective than the higher ones. High salinity resulted in a significant decrease in Vv by day 3 and again by day 10, and a decrease in Vp by day 3. Oyster condition indices were maintained throughout depuration and mortality was low (4% across three trials). Overall these results support the use of mCPC for Vv enumeration and demonstrate the promise of high salinity depuration for PHP of the Eastern oyster. The trend for lower temperatures to be less effective is surprising and indicates a potential interaction between salinity and temperature that should be further investigated. PMID:25310264

Larsen, A M; Rikard, F S; Walton, W C; Arias, C R

2015-01-01

330

Abundance of Vibrio cholerae, V. vulnificus, and V. parahaemolyticus in oysters (Crassostrea virginica) and clams (Mercenaria mercenaria) from Long Island sound.  

PubMed

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

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

2014-12-01

331

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

PubMed Central

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

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

2012-01-01

332

Metalloprotease Vsm Is the Major Determinant of Toxicity for Extracellular Products of Vibrio splendidus? †  

PubMed Central

Genomic data combined with reverse genetic approaches have contributed to the characterization of major virulence factors of Vibrio species; however, these studies have targeted primarily human pathogens. Here, we investigate virulence factors in the oyster pathogen Vibrio splendidus LGP32 and show that toxicity is correlated to the presence of a metalloprotease and its corresponding vsm gene. Comparative genomics showed that an avirulent strain closely related to LGP32 lacked the metalloprotease. The toxicity of LGP32 metalloprotease was confirmed by exposing mollusk and mouse fibroblastic cell lines to extracellular products (ECPs) of the wild type (wt) and a vsm deletion mutant (?vsm mutant). The ECPs of the wt induced a strong cytopathic effect whose severity was cell type dependent, while those of the ?vsm mutant were much less toxic, and exposure to purified protein demonstrated the direct toxicity of the Vsm metalloprotease. Finally, to investigate Vsm molecular targets, a proteomic analysis of the ECPs of both LGP32 and the ?vsm mutant was performed, revealing a number of differentially expressed and/or processed proteins. One of these, the VSA1062 metalloprotease, was found to have significant identity to the immune inhibitor A precursor, a virulence factor of Bacillus thuringiensis. Deletion mutants corresponding to several of the major proteins were constructed by allelic exchange, and the ECPs of these mutants proved to be toxic to both cell cultures and animals. Taken together, these data demonstrate that Vsm is the major toxicity factor in the ECPs of V. splendidus. PMID:18836018

Binesse, Johan; Delsert, Claude; Saulnier, Denis; Champomier-Vergès, Marie-Christine; Zagorec, Monique; Munier-Lehmann, Hélène; Mazel, Didier; Le Roux, Frédérique

2008-01-01

333

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

NASA Astrophysics Data System (ADS)

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.

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

2011-06-01

334

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

PubMed Central

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

Raghunath, Pendru

2015-01-01

335

The Vibrio cholerae type VI secretion system employs diverse effector modules for intraspecific competition  

PubMed Central

Vibrio cholerae is a Gram-negative bacterial pathogen that consists of over 200 serogroups with differing pathogenic potential. Only strains that express the virulence factors cholera toxin (CT) and toxin-coregulated pilus (TCP) are capable of pandemic spread of cholera diarrhoea. Regardless, all V. cholerae strains sequenced to date harbour genes for the type VI secretion system (T6SS) that translocates effectors into neighbouring eukaryotic and prokaryotic cells. Here we report that the effectors encoded within these conserved gene clusters differ widely among V. cholerae strains, and that immunity proteins encoded immediately downstream from the effector genes protect their host from neighbouring bacteria producing corresponding effectors. As a consequence, strains with matching effector-immunity gene sets can coexist, while strains with different sets compete against each other. Thus, the V. cholerae T6SS contributes to the competitive behaviour of this species. PMID:24686479

Unterweger, Daniel; Miyata, Sarah T.; Bachmann, Verena; Brooks, Teresa M.; Mullins, Travis; Kostiuk, Benjamin; Provenzano, Daniele; Pukatzki, Stefan

2014-01-01

336

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

PubMed

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

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

2013-02-01

337

Small Molecule Signaling Systems in Vibrio cholerae  

Microsoft Academic Search

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

Rupak K. Bhadra; Sangita Shah; Bhabatosh Das

338

Isolation and characterisation of Bacillus spp. antagonistic to Vibrio parahaemolyticus for use as probiotics in aquaculture.  

PubMed

Acute gastroenteritis caused by pathogenic Vibrio parahaemolyticus is one of the major factors affecting the development of aquaculture and the safety of seafood. Using the antagonism of probiotics against pathogens is an alternative strategy to antibiotics and a common trend to control food-borne pathogenic bacteria. In this study, a total of 249 isolates were isolated from four types of seafood (Litopenaeus vannamei, Oratosquilla oratoria, Mactra veneriformis and Portunus trituberculatus) and coastal sediment from Liaodong Bay in the Bohai Sea, China with five different separation agars. The most isolates came from the sample of coastal sediment and on agar of 2216E, which accounted for 36.14 and 54.62 % respectively. Twenty-four among 249 isolates displayed direct antimicrobial activity to V. parahaemolyticus with spot inoculation. Sixteen active isolates were selected for extracellular antimicrobial activity using the Oxford cup method. Only strains of B16 and J7 showed extracellular antimicrobial activity and were identified as Bacillus pumilus and Bacillus mojavensis respectively based on the physiological identification and 16S rRNA sequence analysis. Both of the strains B16 and J7 exhibited extracellular hydrolytic enzyme activity and antagonism against more than one indicator bacteria in vitro, which indicates that the two strains have broad potential application as suitable probiotic candidates in aquaculture while B. mojavensis was first reported to inhibit pathogenic Vibrio spp. in vitro. There is no particular trait as to antagonism of B. pumilus B16 or B. mojavensis J7 to Gram-positive or Gram-negative indicator bacteria. PMID:25737203

Liu, Xue-Fei; Li, Ya; Li, Jian-Rong; Cai, Lu-Yun; Li, Xiu-Xia; Chen, Jin-Ru; Lyu, Shu-Xia

2015-05-01

339

Salmonella spp., Vibrio spp., Clostridium perfringens, and Plesiomonas shigelloides in marine and freshwater invertebrates from coastal California ecosystems.  

PubMed

The coastal ecosystems of California are highly utilized by humans and animals, but the ecology of fecal bacteria at the land-sea interface is not well understood. This study evaluated the distribution of potentially pathogenic bacteria in invertebrates from linked marine, estuarine, and freshwater ecosystems in central California. A variety of filter-feeding clams, mussels, worms, and crab tissues were selectively cultured for Salmonella spp., Campylobacter spp., Escherichia coli-O157, Clostridium perfringens, Plesiomonas shigelloides, and Vibrio spp. A longitudinal study assessed environmental risk factors for detecting these bacterial species in sentinel mussel batches. Putative risk factors included mussel collection near higher risk areas for livestock or human sewage exposure, adjacent human population density, season, recent precipitation, water temperature, water type, bivalve type, and freshwater outflow exposure. Bacteria detected in invertebrates included Salmonella spp., C. perfringens, P. shigelloides, Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio alginolyticus. Overall, 80% of mussel batches were culture positive for at least one of the bacterial species, although the pathogens Campylobacter, E. coli-O157, and Salmonella were not detected. Many of the same bacterial species were also cultured from upstream estuarine and riverine invertebrates. Exposure to human sewage sources, recent precipitation, and water temperature were significant risk factors for bacterial detection in sentinel mussel batches. These findings are consistent with the hypothesis that filter-feeding invertebrates along the coast concentrate fecal bacteria flowing from land to sea and show that the relationships between anthropogenic effects on coastal ecosystems and the environmental niches of fecal bacteria are complex and dynamic. PMID:16897302

Miller, W A; Miller, M A; Gardner, I A; Atwill, E R; Byrne, B A; Jang, S; Harris, M; Ames, J; Jessup, D; Paradies, D; Worcester, K; Melli, A; Conrad, P A

2006-08-01

340

Infaunal Burrows Are Enrichment Zones for Vibrio parahaemolyticus?†  

PubMed Central

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

Gamble, Megan D.; Lovell, Charles R.

2011-01-01

341

Homodimerization and Binding of Specific Domains to the Target DNA Are Essential Requirements for HlyU To Regulate Expression of the Virulence Gene rtxA1, Encoding the Repeat-in-Toxin Protein in the Human Pathogen Vibrio vulnificus ? †  

PubMed Central

The virulence gene rtxA1, encoding the repeat-in-toxin protein, plays an essential role in the pathogenesis of Vibrio vulnificus infections. Expression of this gene is controlled by the HlyU regulator by direct contact of the DNA upstream of the rtxA1 toxin operon acting as a derepressor of the H-NS protein. The crystal structure suggests that HlyU forms a homodimer in vitro. However, knowledge of the biological implications of these findings in vivo is limited. In this work, we endeavored to dissect, using genetic and biochemical approaches, the domains of this protein that are essential for homodimer formation and the interaction of HlyU with the target DNA. We identified that residues L18, N22, R25, S54, Q55, L57, W59, R61, K70, and Y77 are essential for the HlyU protein binding to the DNA and that amino acids L17 and L91 are important for HlyU dimerization. We also determined that HlyU homodimer formation is an essential requirement for binding to the upstream region of the rtxA1 operon and is the key feature in relieving the H-NS repression of rtxA1 transcription. PMID:22020641

Liu, Moqing; Rose, Michael; Crosa, Jorge H.

2011-01-01

342

In vitro susceptibility of Vibrio spp . isolated from the environment  

Microsoft Academic Search

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

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

2001-01-01

343

Vibrio diversity and dynamics in the Monterey Bay upwelling region.  

PubMed

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

Mansergh, Sarah; Zehr, Jonathan P

2014-01-01

344

Prevalence of Pandemic Thermostable Direct Hemolysin-Producing Vibrio parahaemolyticus O3:K6 in Seafood and the Coastal Environment in Japan  

Microsoft Academic Search

Although thermostable direct hemolysin (TDH)-producing Vibrio parahaemolyticus has caused many infec- tions in Asian countries, the United States, and other countries, it has been difficult to detect the same pathogen in seafoods and other environmental samples. In this study, we detected and enumerated tdh gene-positive V. parahaemolyticus in Japanese seafoods with a tdh-specific PCR method, a chromogenic agar medium, and

Yukiko Hara-Kudo; Kanji Sugiyama; Mitsuaki Nishibuchi; Ashrafuzzaman Chowdhury; Jun Yatsuyanagi; Yoshimitsu Ohtomo; Akinobu Saito; Hidetoshi Nagano; Tokuhiro Nishina; H. Nakagawa; H. Konuma; M. Miyahara; S. Kumagai

2003-01-01

345

Vibrio cholerae RND Family Efflux Systems Are Required for Antimicrobial Resistance, Optimal Virulence Factor Production, and Colonization of the Infant Mouse Small Intestine  

Microsoft Academic Search

Vibrio cholerae is a gram-negative human intestinal pathogen that causes the diarrheal disease cholera. Humans acquire cholera by ingesting V. cholerae-contaminated food or water. Upon ingestion, V. cholerae encounters several barriers to colonization, including bile acid toxicity and antimicrobial products of the innate immune system. In many gram-negative bacteria, resistance to the antimicrobial effects of these products is mediated by

Xiaowen R. Bina; Daniele Provenzano; Nathalie Nguyen; James E. Bina

2008-01-01

346

The Crystal Structure of a Binary Complex of Two Pseudopilins: EpsI And EpsJ From the Type 2 Secretion System of Vibrio Vulnificus  

Microsoft Academic Search

Type II secretion systems (T2SS) translocate virulence factors from the periplasmic space of many pathogenic bacteria into the extracellular environment. The T2SS of Vibrio cholerae and related species is called the extracellular protein secretion (Eps) system that consists of a core of multiple copies of 11 different proteins. The pseudopilins, EpsG, EpsH, EpsI, EpsJ and EpsK, are five T2SS proteins

M. E. Yanez; K. V. Korotkov; J. Abendroth; W. G. J. Hol

2009-01-01

347

The Crystal Structure of a Binary Complex of two Pseudopilins: EpsI and EpsJ from the Type 2 Secretion System of Vibrio vulnificus  

Microsoft Academic Search

Type II secretion systems (T2SS) translocate virulence factors from the periplasmic space of many pathogenic bacteria into the extracellular environment. The T2SS of Vibrio cholerae and related species is called the extracellular protein secretion (Eps) system that consists of a core of multiple copies of 11 different proteins. The pseudopilins, EpsG, EpsH, EpsI, EpsJ and EpsK, are five T2SS proteins

Marissa E. Yanez; Konstantin V. Korotkov; Jan Abendroth; Wim G. J. Hol

2008-01-01

348

Evolution of Tolerance to PCBs and Susceptibility to a Bacterial Pathogen (Virbrio harveyi) in an Atlantic Killifish Fish (Fundulus heterclitus) from New Bedford (MA, USA) Harbor  

EPA Science Inventory

We are studying adaptation in a population of the non-migratory estuarine fish Fundulus heteroclitus (mummichogs) that has evolved tolerance to some of the effects of the toxic pollutants, polychlorinated biphenyls (PCBs) contaminating their residence site, New Bedford (NB), Mass...

349

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

PubMed Central

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?

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

2014-01-01

350

The function of integron-associated gene cassettes in Vibrio species: the tip of the iceberg  

PubMed Central

The integron is a genetic element that incorporates mobile genes termed gene cassettes into a reserved genetic site via site-specific recombination. It is best known for its role in antibiotic resistance with one type of integron, the class 1 integron, a major player in the dissemination of antibiotic resistance genes across Gram negative pathogens and commensals. However, integrons are ancient structures with over 100 classes (including class 1) present in bacteria from the broader environment. While, the class 1 integron is only one example of an integron being mobilized into the clinical environment, it is by far the most successful. Unlike clinical class 1 integrons which are largely found on plasmids, other integron classes are found on the chromosomes of bacteria and carry diverse gene cassettes indicating a non-antibiotic resistance role(s). However, there is very limited knowledge on what these alternative roles are. This is particularly relevant to Vibrio species where gene cassettes make up approximately 1–3% of their entire genome. In this review, we discuss how emphasis on class 1 integron research has resulted in a limited understanding by the wider research community on the role of integrons in the broader environment. This has the capacity to be counterproductive in solving or improving the antibiotic resistance problem into the future. Furthermore, there is still a significant lack of knowledge on how gene cassettes in Vibrio species drive adaptation and evolution. From research in Vibrio rotiferianus DAT722, new insight into how gene cassettes affect cellular physiology offers new alternative roles for the gene cassette resource. At least a subset of gene cassettes are involved in host surface polysaccharide modification suggesting that gene cassettes may be important in processes such as bacteriophage resistance, adhesion/biofilm formation, protection from grazers and bacterial aggregation. PMID:24367362

Rapa, Rita A.; Labbate, Maurizio

2013-01-01

351

RpoS and Indole Signaling Control the Virulence of Vibrio anguillarum towards Gnotobiotic Sea Bass (Dicentrarchus labrax) Larvae  

PubMed Central

Quorum sensing, bacterial cell-to-cell communication with small signal molecules, controls the virulence of many pathogens. In contrast to other vibrios, neither the VanI/VanR acylhomoserine lactone quorum sensing system, nor the three-channel quorum sensing system affects virulence of the economically important aquatic pathogen Vibrio anguillarum. Indole is another molecule that recently gained attention as a putative signal molecule. The data presented in this study indicate that indole signaling and the alternative sigma factor RpoS have a significant impact on the virulence of V. anguillarum. Deletion of rpoS resulted in increased expression of the indole biosynthesis gene tnaA and in increased production of indole. Both rpoS deletion and the addition of exogenous indole (50–100 µM) resulted in decreased biofilm formation, exopolysaccharide production (a phenotype that is required for pathogenicity) and expression of the exopolysaccharide synthesis gene wbfD. Further, indole inhibitors increased the virulence of the rpoS deletion mutant, suggesting that indole acts downstream of RpoS. Finally, in addition to the phenotypes found to be affected by indole, the rpoS deletion mutant also showed increased motility and decreased sensitivity to oxidative stress. PMID:25360804

Li, Xuan; Yang, Qian; Dierckens, Kristof; Milton, Debra L.; Defoirdt, Tom

2014-01-01

352

Vibrio parahaemolyticus strengthens their virulence through modulation of cellular reactive oxygen species in vitro  

PubMed Central

Vibrio parahaemolyticus (Vp) is one of the emergent food-borne pathogens that are commensally associated with various shellfish species throughout the world. It is strictly environmental and many strains are pathogenic to humans. The virulent strains cause distinct diseases, including wound infections, septicemia, and most commonly, acute gastroenteritis, which is acquired through the consumption of raw or undercooked seafood, especially shellfish. Vp has two type three secretion systems (T3SSs), which triggering its cytotoxicity and enterotoxicity via their effectors. To better understand the pathogenesis of Vp, we established a cell infection model in vitro using a non-phagocytic cell line. Caco-2 cells were infected with different strains of Vp (pandemic and non-pandemic strains) and several parameters of cytotoxicity were measured together with adhesion and invasion indices, which reflect the pathogen's virulence. Our results show that Vp adheres to cell monolayers and can invade non-phagocytic cells. It also survives and persists in non-phagocytic cells by modulating reactive oxygen species (ROS), allowing its replication, and resulting in complete cellular destruction. We conclude that the pathogenicity of Vp is based on its capacities for adhesion and invasion. Surprisingly's; enhanced of ROS resistance period could promote the survival of Vp inside the intestinal tract, facilitating tissue infection by repressing the host's oxidative stress response. PMID:25566508

El-Malah, Shimaa S.; Yang, Zhenquan; Hu, Maozhi; Li, Qiuchun; Pan, Zhiming; Jiao, Xinan

2014-01-01

353

Year round patchiness of Vibrio vulnificus within a temperate texas bay  

PubMed Central

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

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

2012-01-01

354

Localization of Vibrio cholerae O1 in the intestinal tissue.  

PubMed

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

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

1993-12-01

355

Uncertainty in Model Predictions of Vibrio vulnificus Response to Climate Variability and Change: A Chesapeake Bay Case Study  

PubMed Central

The effect that climate change and variability will have on waterborne bacteria is a topic of increasing concern for coastal ecosystems, including the Chesapeake Bay. Surface water temperature trends in the Bay indicate a warming pattern of roughly 0.3–0.4°C per decade over the past 30 years. It is unclear what impact future warming will have on pathogens currently found in the Bay, including Vibrio spp. Using historical environmental data, combined with three different statistical models of Vibrio vulnificus probability, we explore the relationship between environmental change and predicted Vibrio vulnificus presence in the upper Chesapeake Bay. We find that the predicted response of V. vulnificus probability to high temperatures in the Bay differs systematically between models of differing structure. As existing publicly available datasets are inadequate to determine which model structure is most appropriate, the impact of climatic change on the probability of V. vulnificus presence in the Chesapeake Bay remains uncertain. This result points to the challenge of characterizing climate sensitivity of ecological systems in which data are sparse and only statistical models of ecological sensitivity exist. PMID:24874082

Urquhart, Erin A.; Zaitchik, Benjamin F.; Waugh, Darryn W.; Guikema, Seth D.; Del Castillo, Carlos E.

2014-01-01

356

Vaccines for viral and bacterial pathogens causing acute gastroenteritis: Part II: Vaccines for Shigella, Salmonella, enterotoxigenic E. coli (ETEC) enterohemorragic E. coli (EHEC) and Campylobacter jejuni.  

PubMed

In Part II we discuss the following bacterial pathogens: Shigella, Salmonella (non-typhoidal), diarrheogenic E. coli (enterotoxigenic and enterohemorragic) and Campylobacter jejuni. In contrast to the enteric viruses and Vibrio cholerae discussed in Part I of this series, for the bacterial pathogens described here there is only one licensed vaccine, developed primarily for Vibrio cholerae and which provides moderate protection against enterotoxigenic E. coli (ETEC) (Dukoral®), as well as a few additional candidates in advanced stages of development for ETEC and one candidate for Shigella spp. Numerous vaccine candidates in earlier stages of development are discussed. PMID:25715096

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

2015-03-01

357

Factors That Explain Excretion of Enteric Pathogens by Persons Without Diarrhea  

PubMed Central

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

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

2012-01-01

358

Cholix Toxin, a Novel ADP-ribosylating Factor from Vibrio cholerae  

SciTech Connect

The ADP-ribosyltransferases are a class of enzymes that display activity in a variety of bacterial pathogens responsible for causing diseases in plants and animals, including those affecting mankind, such as diphtheria, cholera, and whooping cough. We report the characterization of a novel toxin from Vibrio cholerae, which we call cholix toxin. The toxin is active against mammalian cells (IC50 = 4.6 {+-} 0.4 ng/ml) and crustaceans (Artemia nauplii LD50 = 10 {+-} 2 {mu}g/ml). Here we show that this toxin is the third member of the diphthamide-specific class of ADP-ribose transferases and that it possesses specific ADP-ribose transferase activity against ribosomal eukaryotic elongation factor 2. We also describe the high resolution crystal structures of the multidomain toxin and its catalytic domain at 2.1- and 1.25-{angstrom} resolution, respectively. The new structural data show that cholix toxin possesses the necessary molecular features required for infection of eukaryotes by receptor-mediated endocytosis, translocation to the host cytoplasm, and inhibition of protein synthesis by specific modification of elongation factor 2. The crystal structures also provide important insight into the structural basis for activation of toxin ADP-ribosyltransferase activity. These results indicate that cholix toxin may be an important virulence factor of Vibrio cholerae that likely plays a significant role in the survival of the organism in an aquatic environment.

Jorgensen, Rene; Purdy, Alexandra E.; Fieldhouse, Robert J.; Kimber, Matthew S.; Bartlett, Douglas H.; Merrill, A. Rod (Guelph); (NIH); (UCSD)

2008-07-15

359

Cloning, expressing, and hemolysis of tdh, trh and tlh genes of Vibrio parahaemolyticus  

NASA Astrophysics Data System (ADS)

Vibrio parahaemolyticus (VP) is one of the pathogenic vibrios endangering net-cage cultured Pseudosciaena crocea, Fennerpenaeus chinensis, and shellfish in coastal areas of China. Several types of hemolysins produced by Vp have been characterized as major virulence factors. They are thermostable direct hemolysin (TDH), TDH-related hemolysin (TRH) and thermolabile hemolysin (TLH). In this study, we cloned tdh, trh, and tlh genes from the genome DNA of VP by polymerase chain reaction (PCR). We ligated the three genes into prokaryotic expression vector pET-28a (+), and transformed the recombinant plasmids into Escherichia coli BL21 (DE3). The expression of recombinant proteins was induced by isopropyl-?-D-thiogalacto-pyranoside (IPTG). The recombinant proteins were expressed in a form of inclusion bodies and thus purified with Ni-NTA affinity chromatography. Western blotting results showed that recombinant proteins, TDH, TRH and TLH, could be recognized by rabbit anti-VP serum. The three purified proteins were renatured by gradient dialysis. The renatured proteins exhibited hemolytic activity except for TLH in the presence of phosphatidylcholine. These results not only are helpful for better understanding these genes' functions under a single factor level, but also provide evidence for VP vaccine engineering.

Zhao, Yonggang; Tang, Xiaoqian; Zhan, Wenbin

2011-09-01

360

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

PubMed

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

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

2015-01-14

361

Quorum Sensing Contributes to Natural Transformation of Vibrio cholerae in a Species-Specific Manner?  

PubMed Central

Although it is a human pathogen, Vibrio cholerae is a regular member of aquatic habitats, such as coastal regions and estuaries. Within these environments, V. cholerae often takes advantage of the abundance of zooplankton and their chitinous molts as a nutritious surface on which the bacteria can form biofilms. Chitin also induces the developmental program of natural competence for transformation in several species of the genus Vibrio. In this study, we show that V. cholerae does not distinguish between species-specific and non-species-specific DNA at the level of DNA uptake. This is in contrast to what has been shown for other Gram-negative bacteria, such as Neisseria gonorrhoeae and Haemophilus influenzae. However, species specificity with respect to natural transformation still occurs in V. cholerae. This is based on a positive correlation between quorum sensing and natural transformation. Using mutant-strain analysis, cross-feeding experiments, and synthetic cholera autoinducer-1 (CAI-1), we provide strong evidence that the species-specific signaling molecule CAI-1 plays a major role in natural competence for transformation. We suggest that CAI-1 can be considered a competence pheromone. PMID:21784943

Suckow, Gaia; Seitz, Patrick; Blokesch, Melanie

2011-01-01

362

Interspecific Quorum Sensing Mediates the Resuscitation of Viable but Nonculturable Vibrios  

PubMed Central

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

Ayrapetyan, Mesrop; Williams, Tiffany C.

2014-01-01

363

Mechanistic insights into filamentous phage integration in Vibrio cholerae  

PubMed Central

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

Das, Bhabatosh

2014-01-01

364

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

Microsoft Academic Search

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

C. R. JENKIN; D. ROWLEY

1959-01-01

365

21 CFR 866.3930 - Vibrio cholerae serological reagents.  

Code of Federal Regulations, 2010 CFR

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

2010-04-01

366

21 CFR 866.3930 - Vibrio cholerae serological reagents.  

Code of Federal Regulations, 2014 CFR

...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...

2014-04-01

367

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

PubMed

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

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

2015-02-01

368

Wound Infection due to Vibrio vulnificus in Spain  

Microsoft Academic Search

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

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

2002-01-01

369

Association of CRISPR/Cas evolution with Vibrio parahaemolyticus virulence factors and genotypes.  

PubMed

Clustered regularly interspaced short palindromic repeats (CRISPR), which is considered to be an immune system for bacteria, has been widely used as a tool for genome editing and genotyping. It has also been reported to be associated with virulence factors in some bacteria. To understand the role of CRISPR in the virulence and evolution of pathogenic Vibrio parahaemolyticus, 154 V. parahaemolyticus strains isolated from clinical samples and 54 strains from food samples taken in Shenzhen, China were subjected to a correlation analysis of CRISPR and virulence factors TDH and TRH. We also performed multilocus sequence typing (MLST) for genotype analysis. Six different CRISPR sequence types (CSTs) of V. parahaemolyticus were identified, and CSTs were found to be significantly associated with the virulence factors tested and MLST genotype. Therefore, CSTs provide insight into the evolution of V. parahaemolyticus. Moreover, identification of CSTs may lend insight into the virulence potential of strains. PMID:25455966

Sun, Honghu; Li, Yinghui; Shi, Xiaolu; Lin, Yiman; Qiu, Yaqun; Zhang, Jinjin; Liu, Yao; Jiang, Min; Zhang, Zhen; Chen, Qiongcheng; Sun, Qun; Hu, Qinghua

2015-01-01

370

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

PubMed

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

Paydar, Mohammadjavad; Thong, Kwai Lin

2013-10-01

371

Genetic analysis of Drosophila melanogaster susceptibility to intestinal Vibrio cholerae infection  

PubMed Central

Summary We previously demonstrated that Vibrio cholerae is able to colonize the intestine of the fly to produce a lethal infection. Here we present the results of a genetic screen undertaken to identify factors that alter susceptibility of the fly to intestinal V. cholerae infection. In this model of infection, the Eiger/Wengen signalling pathway protects the fly against infection. Furthermore, mutations within the IMD signalling pathway increase resistance to intestinal V. cholerae infection and increase programmed cell death within the intestinal epithelium during infection. We propose that programmed cell death protects the intestinal epithelium against V. cholerae infection and therefore that the fly may serve as a useful model in which to study modulation of intestinal epithelial cell survival by commensal and pathogenic intestinal bacteria as well as the pathological processes leading to erosion of the intestinal epithelium and intestinal malignancy. PMID:19046341

Berkey, Cristin D.; Blow, Nathan; Watnick, Paula I.

2009-01-01

372

Identification of a novel vaccine candidate by immunogenic screening of Vibrio parahaemolyticus outer membrane proteins.  

PubMed

Vibrio parahaemolyticus is an important halophilous pathogen that can cause not only a broad range of disease in aquatic animals but also serious seafood-borne illness in humans as a result of the consumption of seafood. To avoid the use of antibiotics, it is critical to identify protective antigens for developing highly effective vaccines against this pathogen. Outer membrane proteins (OMPs) have been suggested as potential vaccine candidates for conferring protection against infection. In this study, we identified novel immunogenic OMPs using an immune assay with serum antibodies from mice infected by V. parahaemolyticus combined with mass spectrometry analysis. Nine OMPs were identified to be immunogenic proteins, and four of these identified proteins with relatively low abundance in OMP profiles, LptD, VP0802, VP1243 and VP0966, were determined to have immunogenicity for the first time. One OMP of interest, VP0802, is highly conserved among major Vibrio species and was proposed to adopt a ?-barrel conformation and to be a member of the OprD protein family by bioinformatic analysis. The immunogenicity and protective efficacy of VP0802 were further evaluated by bacterial challenge postimmunization in a mouse model. VP0802 was confirmed to be highly immunogenic and to offer strong protection against V. parahaemolyticus infection, with an RPS of at least 66.7. Efficient clearance of bacteria from the blood of vaccinated mice was also observed. Moreover, upregulation of VP0802 expression was found after bacteria were exposed to fresh sera. These data, taken together, suggest that VP0802 is a promising candidate for the development of a subunit vaccine to prevent V. parahaemolyticus infection. PMID:25236587

Li, Chuchu; Ye, Zhicang; Wen, Liangyou; Chen, Ran; Tian, Lihua; Zhao, Fukun; Pan, Jianyi

2014-10-21

373

Transcriptome analysis of Vibrio parahaemolyticus in type III secretion system 1 inducing conditions  

PubMed Central

Vibrio parahaemolyticus is an emerging bacterial pathogen capable of causing inflammatory gastroenteritis, wound infections, and septicemia. As a food-borne illness, infection is most frequently associated with the consumption of raw or undercooked seafood, particularly shellfish. It is the primary cause of Vibrio-associated food-borne illness in the United States and the leading cause of food-borne illness in Japan. The larger of its two chromosomes harbors a set of genes encoding type III section system 1 (T3SS1), a virulence factor present in all V. parahaemolyticus strains that is similar to the Yersinia ysc T3SS. T3SS1 translocates effector proteins into eukaryotic cells where they induce changes to cellular physiology and modulate host-pathogen interactions. T3SS1 is also responsible for cytotoxicity toward several different cultured cell lines as well as mortality in a mouse model. Herein we used RNA-seq to obtain global transcriptome patterns of V. parahaemolyticus under conditions that either induce [growth in Dulbecco's Modified Eagle Medium (DMEM) media, in trans expression of transcriptional regulator exsA] or repress T3SS1 expression (growth in LB-S media, in trans exsD expression) and during infection of HeLa cells over time. Comparative transcriptomic analysis demonstrated notable differences in the expression patterns under inducing conditions and was also used to generate an expression profile of V. parahaemolyticus during infection of HeLa cells. In addition, we identified several new genes that are associated with T3SS1 expression and may warrant further study. PMID:24478989

Nydam, Seth D.; Shah, Devendra H.; Call, Douglas R.

2014-01-01

374

Viscosity dictates metabolic activity of Vibrio ruber  

PubMed Central

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

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

2012-01-01

375

Antibacterial activity of silver and zinc nanoparticles against Vibrio cholerae and enterotoxic Escherichia coli.  

PubMed

Vibrio cholerae and enterotoxic Escherichia coli (ETEC) remain two dominant bacterial causes of severe secretory diarrhea and still a significant cause of death, especially in developing countries. In order to investigate new effective and inexpensive therapeutic approaches, we analyzed nanoparticles synthesized by a green approach using corresponding salt (silver or zinc nitrate) with aqueous extract of Caltropis procera fruit or leaves. We characterized the quantity and quality of nanoparticles by UV-visible wavelength scans and nanoparticle tracking analysis. Nanoparticles could be synthesized in reproducible yields of approximately 10(8) particles/ml with mode particles sizes of approx. 90-100 nm. Antibacterial activity against two pathogens was assessed by minimal inhibitory concentration assays and survival curves. Both pathogens exhibited similar resistance profiles with minimal inhibitory concentrations ranging between 5×10(5) and 10(7) particles/ml. Interestingly, zinc nanoparticles showed a slightly higher efficacy, but sublethal concentrations caused adverse effects and resulted in increased biofilm formation of V. cholerae. Using the expression levels of the outer membrane porin OmpT as an indicator for cAMP levels, our results suggest that zinc nanoparticles inhibit adenylyl cyclase activity. This consequently deceases the levels of this second messenger, which is a known inhibitor of biofilm formation. Finally, we demonstrated that a single oral administration of silver nanoparticles to infant mice colonized with V. cholerae or ETEC significantly reduces the colonization rates of the pathogens by 75- or 100-fold, respectively. PMID:25466205

Salem, Wesam; Leitner, Deborah R; Zingl, Franz G; Schratter, Gebhart; Prassl, Ruth; Goessler, Walter; Reidl, Joachim; Schild, Stefan

2015-01-01

376

Antibacterial activity of silver and zinc nanoparticles against Vibrio cholerae and enterotoxic Escherichia coli  

PubMed Central

Vibrio cholerae and enterotoxic Escherichia coli (ETEC) remain two dominant bacterial causes of severe secretory diarrhea and still a significant cause of death, especially in developing countries. In order to investigate new effective and inexpensive therapeutic approaches, we analyzed nanoparticles synthesized by a green approach using corresponding salt (silver or zinc nitrate) with aqueous extract of Caltropis procera fruit or leaves. We characterized the quantity and quality of nanoparticles by UV–visible wavelength scans and nanoparticle tracking analysis. Nanoparticles could be synthesized in reproducible yields of approximately 108 particles/ml with mode particles sizes of approx. 90–100 nm. Antibacterial activity against two pathogens was assessed by minimal inhibitory concentration assays and survival curves. Both pathogens exhibited similar resistance profiles with minimal inhibitory concentrations ranging between 5 × 105 and 107 particles/ml. Interestingly, zinc nanoparticles showed a slightly higher efficacy, but sublethal concentrations caused adverse effects and resulted in increased biofilm formation of V. cholerae. Using the expression levels of the outer membrane porin OmpT as an indicator for cAMP levels, our results suggest that zinc nanoparticles inhibit adenylyl cyclase activity. This consequently deceases the levels of this second messenger, which is a known inhibitor of biofilm formation. Finally, we demonstrated that a single oral administration of silver nanoparticles to infant mice colonized with V. cholerae or ETEC significantly reduces the colonization rates of the pathogens by 75- or 100-fold, respectively. PMID:25466205

Salem, Wesam; Leitner, Deborah R.; Zingl, Franz G.; Schratter, Gebhart; Prassl, Ruth; Goessler, Walter; Reidl, Joachim; Schild, Stefan

2015-01-01

377

Characterization of a novel zinc transporter ZnuA acquired by Vibrio parahaemolyticus through horizontal gene transfer  

PubMed Central

Vibrio parahaemolyticus is a clinically important foodborne pathogen that causes acute gastroenteritis worldwide. It has been shown that horizontal gene transfer (HGT) contributes significantly to virulence development of V. parahaemolyticus. In this study, we identified a novel znuA homolog (vpa1307) that belongs to a novel subfamily of ZnuA, a bacterial zinc transporter. The vpa1307 gene is located upstream of the V. parahaemolyticus pathogenicity island (Vp-PAIs) in both tdh-positive and trh-positive V. parahaemolyticus strains. Phylogenetic analysis revealed the exogenous origin of vpa1307 with 40% of V. parahaemolyticus clinical isolates possessing this gene. The expression of vpa1307 gene in V. parahaemolyticus clinical strain VP3218 is induced under zinc limitation condition. Gene deletion and complementation assays confirmed that vpa1307 contributes to the growth of VP3218 under zinc depletion condition and that conserved histidine residues of Vpa1307 contribute to its activity. Importantly, vpa1307 contributes to the cytotoxicity of VP3218 in HeLa cells and a certain degree of virulence in murine model. These results suggest that the horizontally acquired znuA subfamily gene, vpa1307, contributes to the fitness and virulence of Vibrio species. PMID:24133656

Liu, Ming; Yan, Meiying; Liu, Lizhang; Chen, Sheng

2013-01-01

378

Insights into Vibrio cholerae Intestinal Colonization from Monitoring Fluorescently Labeled Bacteria  

PubMed Central

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

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

2014-01-01

379

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

PubMed

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

Alipour, Majid; Issazadeh, Khosro; Soleimani, Javad

2014-01-01

380

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

PubMed

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

Gladney, Lori M; Tarr, Cheryl L

2014-11-01

381

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

PubMed Central

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

2013-01-01

382

Probes and polymerase chain reaction for detection of food-borne bacterial pathogens  

Microsoft Academic Search

DNA-hybridization and the polymerase chain reaction (PCR) are techniques commonly used to detect pathogenic bacteria. In this paper, the use of these techniques for detection of Salmonella, E. coli, V. cholerae, non-O1 Vibrio, Yersinia enterocolitica, Campylobacter, Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, and C. botulinum is reviewed with emphasis on application in food microbiology. In food control, DNA-techniques

J. E Olsen; S Aabo; W Hill; S Notermans; K Wernars; P. E Granum; T Popovic; H. N Rasmussen; Ø Olsvik

1995-01-01

383

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

PubMed

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

Ren, Tingting; Su, Yi-Cheng

2006-08-01

384

The apparent quorum-sensing inhibitory activity of pyrogallol is a side effect of peroxide production.  

PubMed

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

Defoirdt, Tom; Pande, Gde Sasmita Julyantoro; Baruah, Kartik; Bossier, Peter

2013-06-01

385

Adaptive response to cold temperatures in Vibrio vulnificus.  

PubMed

The effectiveness of rapid chilling or freezing of oysters to reduce Vibrio vulnificus levels in shellfish may be compromised by product handling procedures that permit cold adaptation. When a V. vulnificus culture was shifted from 35 degrees C to 6 degrees C conditions, it underwent transition to a non-culturable state. Cells adapted to 15 degrees C prior to change to 6 degrees C condition, however, remain viable and culturable. In addition, cultures adapted to 15 degrees C were able to survive better upon freezing at -78 degrees C compared with cultures frozen directly from 35 degrees C. Inhibition of protein synthesis by addition of chloramphenicol in a V. vulnificus culture immediately prior to the exposure to the adaptive temperature eliminated inducible cold tolerance. These results suggest that cold-adaptive "protective" proteins may enhance survival and tolerance at cold temperatures. In addition, removal of iron from the growth medium by adding 2,2'-Dipyridyl prior to cold adaptation decreased the viability by approximately 2 logarithm levels. This suggests that iron plays an important role in adaptation at cold temperatures. Analysis of total cellular proteins on an SDS polyacrylamide gel electrophoresis, labeled with 35S-methionine during exposure at 15 degrees C, showed elevated expressions of a 6-kDa and a 40-kDa protein and decreased expression of an 80-kDa protein. These results suggest that, for V. vulnificus, survival and tolerance at cold temperatures could be due to the expression of cold-adaptive proteins other than previously documented major cold shock proteins such as CS7.4 and CsdA. In this study, for the first time we have shown that exposure to an intermediate cold temperature (15 degrees C) causes a cold adaptive response, helping this pathogen remain in culturable state when exposed to a much colder temperature (6 degrees C). This adaptive nature to cold temperatures could be important for shellfish industry efforts to reduce the risk of V. vulnificus infection from consuming raw oysters. PMID:9922468

Bryan, P J; Steffan, R J; DePaola, A; Foster, J W; Bej, A K

1999-03-01

386

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

PubMed Central

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

Spira, W M; Fedorka-Cray, P J

1983-01-01

387

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

PubMed

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

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

2014-04-01

388

Comparative genomic analysis of clinical and environmental Vibrio vulnificus isolates revealed biotype 3 evolutionary relationships  

PubMed Central

In 1996 a common-source outbreak of severe soft tissue and bloodstream infections erupted among Israeli fish farmers and fish consumers due to changes in fish marketing policies. The causative pathogen was a new strain of Vibrio vulnificus, named biotype 3, which displayed a unique biochemical and genotypic profile. Initial observations suggested that the pathogen erupted as a result of genetic recombination between two distinct populations. We applied a whole genome shotgun sequencing approach using several V. vulnificus strains from Israel in order to study the pan genome of V. vulnificus and determine the phylogenetic relationship of biotype 3 with existing populations. The core genome of V. vulnificus based on 16 draft and complete genomes consisted of 3068 genes, representing between 59 and 78% of the whole genome of 16 strains. The accessory genome varied in size from 781 to 2044 kbp. Phylogenetic analysis based on whole, core, and accessory genomes displayed similar clustering patterns with two main clusters, clinical (C) and environmental (E), all biotype 3 strains formed a distinct group within the E cluster. Annotation of accessory genomic regions found in biotype 3 strains and absent from the core genome yielded 1732 genes, of which the vast majority encoded hypothetical proteins, phage-related proteins, and mobile element proteins. A total of 1916 proteins (including 713 hypothetical proteins) were present in all human pathogenic strains (both biotype 3 and non-biotype 3) and absent from the environmental strains. Clustering analysis of the non-hypothetical proteins revealed 148 protein clusters shared by all human pathogenic strains; these included transcriptional regulators, arylsulfatases, methyl-accepting chemotaxis proteins, acetyltransferases, GGDEF family proteins, transposases, type IV secretory system (T4SS) proteins, and integrases. Our study showed that V. vulnificus biotype 3 evolved from environmental populations and formed a genetically distinct group within the E-cluster. The unique epidemiological circumstances facilitated disease outbreak and brought this genotype to the attention of the scientific community. PMID:25642229

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

2015-01-01

389

Detection of major diarrheagenic bacterial pathogens by multiplex PCR panels.  

PubMed

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

Sjöling, Åsa; Sadeghipoorjahromi, Leila; Novak, Daniel; Tobias, Joshua

2015-03-01

390

Pathogenic enterobacteria in lemurs associated with anthropogenic disturbance.  

PubMed

As human population density continues to increase exponentially, speeding the reduction and fragmentation of primate habitat, greater human-primate contact is inevitable, making higher rates of pathogen transmission likely. Anthropogenic effects are particularly evident in Madagascar, where a diversity of endemic lemur species are threatened by rapid habitat loss. Despite these risks, knowledge of how anthropogenic activities affect lemur exposure to pathogens is limited. To improve our understanding of this interplay, we non-invasively examined six species of wild lemurs in Ranomafana National Park for enteric bacterial pathogens commonly associated with diarrheal disease in human populations in Madagascar. Patterns of infection with Enterotoxigenic Escherichia coli, Shigella spp., Salmonella enterica, Vibrio cholerae, and Yersinia spp. (enterocolitica and pseudotuberculosis) were compared between lemurs inhabiting intact forest and lemurs inhabiting degraded habitat with frequent exposure to tourism and other human activity. Fecal samples acquired from humans, livestock, and rodents living near the degraded habitat were also screened for these bacteria. Remarkably, only lemurs living in disturbed areas of the park tested positive for these pathogens. Moreover, all of these pathogens were present in the human, livestock, and/or rodent populations. These data suggest that lemurs residing in forests altered or frequented by people, livestock, or peridomestic rodents, are at risk for infection by these diarrhea-causing enterobacteria and other similarly transmitted pathogens. PMID:25328106

Bublitz, DeAnna C; Wright, Patricia C; Rasambainarivo, Fidisoa T; Arrigo-Nelson, Summer J; Bodager, Jonathan R; Gillespie, Thomas R

2015-03-01

391

Mechanism of Vibrio cholerae autoinducer-1 biosynthesis.  

PubMed

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

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

2011-04-15

392

Characterization of Undermethylated Sites in Vibrio cholerae  

PubMed Central

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

Dalia, Ankur B.; Lazinski, David W.

2013-01-01

393

Surface-attachment sequence in Vibrio Cholerae  

NASA Astrophysics Data System (ADS)

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

Utada, Andrew; Gibiansky, Maxsim; Wong, Gerard

2013-03-01

394

LECT2 improves the outcomes in ayu with Vibrio anguillarum infection via monocytes/macrophages.  

PubMed

Leukocyte cell-derived chemotaxin 2 (LECT2) is reported to be a cytokine involved in the immune response against pathogenic microorganisms in fish. However, its accurate function in whole fish remains unclear. In this study, we provide the first report on the effect of LECT2 on fish defenses against pathogens in vivo. The administration of recombinant LECT2 improved the survival rate of Vibrio anguillarum infected ayu. The bacterial burden of V. anguillarum infected ayu was decreased in LECT2-treated ayu blood, liver, spleen, and kidney compared with saline control. In bacteria-infected ayu, LECT2 treatment altered the mRNA expression of cytokines, including TNF?, IL-1?, and IL-10, which are all important for the inflammatory response in fish. LECT2 treatment also reduced histological damage in bacteria-infected ayu, and increased peritoneal monocytes/macrophages in both healthy and infected ayu at 12 h post infection. When ayu monocytes/macrophages were depleted by clodronate-liposomes treatment, LECT2 treatment did not increase the survival rate of bacteria-infected fish compared with healthy control fish. Thus our results suggest that LECT2 can modulate host defense in ayu and mediate antibacterial protection against V. anguillarum through monocytes/macrophages. PMID:25462453

Chen, Jiong; Chen, Qiang; Lu, Xin-Jiang; Li, Chang-Hong

2014-12-01

395

Circulation and transmission of clones of Vibrio cholerae during cholera outbreaks.  

PubMed

Cholera is still a major public health problem. The underlying bacterial pathogen Vibrio cholerae (V. cholerae) is evolving and some of its mutations have set the stage for outbreaks. After V. cholerae acquired the mobile elements VSP I & II, the El Tor pandemic began and spread across the tropics. The replacement of the O1 serotype encoding genes with the O139 encoding genes triggered an outbreak that swept across the Indian subcontinent. The sxt element generated a third selective sweep and most recently a fourth sweep was associated with the exchange of the El Tor ctx allele for a classical ctx allele in the El Tor background. In Kenya, variants of this fourth selective sweep have differentiated and become endemic residing in and emerging from environmental reservoirs. On a local level, studies in Bangladesh have revealed that outbreaks may arise from a nonrandom subset of the genetic lineages in the environment and as the population of the pathogen expands, many novel mutations may be found increasing the amount of genetic variation, a phenomenon known as a founder flush. In Haiti, after the initial invasion and expansion of V. cholerae in 2010, a second outbreak occurred in the winter of 2011-2012 driven by natural selection of specific mutations. PMID:24407776

Stine, O Colin; Morris, J Glenn

2014-01-01

396

Rapid, sensitive detection of Vibrio anguillarum using loop-mediated isothermal amplification  

NASA Astrophysics Data System (ADS)

Vibrio anguillarum is an important bacterial pathogen of aquatic organisms and a significant problem in aquatic farming. The rapid detection and identification of V. anguillarum, and other pathogens that infect marine organisms, is crucial to effective disease management. In this study, we developed a loop-mediated amplification (LAMP) assay to detect V. anguillarum in an hour in a single tube without the need for thermal cycling. Conserved regions of the metalloproteinase ( empA) gene of V. anguillarum served as the targets for primer design. A fragment of the empA gene was amplified at 65°C in the presence of the primer mixture and Bst DNA polymerase. In the optimized LAMP assay, 6.7 pg of V. anguillarum DNA could be detected. Six strains of V. anguillarum and 17 strains of non- V. anguillarum bacteria were used in this study to evaluate the species specificity of the primers. The six V. anguillarum strains gave a positive result in the LAMP assay. This method was also validated in V. anguillarum-infected fish. This LAMP method is more sensitive than PCR in the detection of V. anguillarum and shows good species specificity. The LAMP assay is therefore an effective method for the quick detection of V. anguillarum both in the laboratory and in the field.

Gao, Hongwei; Li, Fuhua; Zhang, Xiaojun; Wang, Bing; Xiang, Jianhai

2010-01-01

397

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

PubMed

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

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

2012-01-01

398

Members of the human gut microbiota involved in recovery from Vibrio cholerae infection.  

PubMed

Given the global burden of diarrhoeal diseases, 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 diarrhoea caused by Vibrio cholerae represents a dramatic example of enteropathogen invasion and gut microbial community disruption. Here we conduct a detailed time-series metagenomic study of faecal microbiota collected during the acute diarrhoeal and recovery phases of cholera in a cohort of Bangladeshi adults living in an area with a high burden of disease. 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 children. To define the underlying mechanisms, we introduce into gnotobiotic mice an artificial community 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 children. One of the species, Ruminococcus obeum, exhibits consistent increases in its relative abundance upon V. cholerae infection of the mice. Follow-up analyses, including mono- and co-colonization studies, establish 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 discloses 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

Hsiao, Ansel; Ahmed, A M Shamsir; Subramanian, Sathish; Griffin, Nicholas W; Drewry, Lisa L; Petri, William A; Haque, Rashidul; Ahmed, Tahmeed; Gordon, Jeffrey I

2014-11-20