| vibrio anguillarum serogroup o3 and v. anguillarum-like serogroup o3 cross-reactive species--comparison and characterization. | forty-five vibrio anguillarum-like isolates reacting with v. anguillarum serogroup o3 antiserum were examined in 30 characters to clarify their phenotypical properties, while their genotype was examined by ribotyping. the strains were isolated from diseased and dead fish or from environmental sources such as water, sediment, plankton, and faeces and gills of healthy fish. phenotypically, the similarity of all the strains was more than 90%. however, significant differences between the fish-associ ... | 1997 | 12452596 |
| antibiotic resistance and plasmid profile of environmental isolates of vibrio species from mai po nature reserve, hong kong. | in this study, three environmental isolates of vibrio species were isolated from water and sediment samples of mai po nature reserve, hong kong sar. they were identified to be vibrio cholerae mp-1, vibrio aestuarianus mp-2 and vibrio vulnificus mp-3 by both biochemical test and subsequent full-length 16s rdna sequencing. both disc diffusion susceptibility test and microplate dilution technique were used to investigate the antibiotic resistance profile of these three bacteria. results from both a ... | 2006 | 16680524 |
| molecular and phenotypic characterization of vibrio aestuarianus subsp. francensis subsp. nov., a pathogen of the oyster crassostrea gigas. | eleven vibrio isolates invading the hemolymph of live and moribund oysters (crassostrea gigas) collected in the field and from a hatchery in france, were characterized by a polyphasic approach. phylogenetic analysis of 16s rrna, gyrb and toxr genes indicated high homogeneity between these strains and the vibrio aestuarianus type strain (atcc35048(t)), and confirmed previous 16s rrna analysis. in contrast, dna:dna hybridization was from 61% to 100%, while phenotypic characters and virulence tests ... | 2008 | 18718730 |
| evidence for the involvement of pathogenic bacteria in summer mortalities of the pacific oyster crassostrea gigas. | a study was conducted to investigate the involvement of bacteria in oyster mortalities during summer. moribund and apparently healthy oysters were sampled during mortality events along the french coast and in rearing facilities, usually when temperature reached 19 degrees c or higher, and oysters were in the gonadal maturation phase. hemolymph samples were aseptically withdrawn and submitted to bacteriological analysis. in healthy oysters, bacteria colonized hemolymph at low concentrations depen ... | 2007 | 17245611 |
| impact of 20:4n-6 supplementation on the fatty acid composition and hemocyte parameters of the pacific oyster crassostrea gigas. | arachidonic acid (20:4n-6, ara) and its eicosanoid metabolites have been demonstrated to be implicated in immune functions of vertebrates, fish, and insects. thus, the aim of this study was to assess the impact of ara supplementation on the fa composition and hemocyte parameters of oysters crassostrea gigas. oyster dietary conditioning consisted of direct addition of ara solutions at a dose of 0, 0.25, or 0.41 microg ara per ml of seawater into tanks in the presence or absence of t-iso algae. re ... | 2006 | 16981435 |
| cellular and molecular hemocyte responses of the pacific oyster, crassostrea gigas, following bacterial infection with vibrio aestuarianus strain 01/32. | the strategies used by bacterial pathogens to circumvent host defense mechanisms remain largely undefined in bivalve molluscs. in this study, we investigated experimentally the interactions between the pacific oyster (crassostrea gigas) immune system and vibrio aestuarianus strain 01/32, a pathogenic bacterium originally isolated from moribund oysters. first, an antibiotic-resistant v. aestuarianus strain was used to demonstrate that only a limited number of bacterial cells was detected in the h ... | 2006 | 16978900 |
| effects of extracellular products from the pathogenic vibrio aestuarianus strain 01/32 on lethality and cellular immune responses of the oyster crassostrea gigas. | vibrio aestuarianus strain 01/32 was previously shown to be pathogenic to crassostrea gigas juveniles. to investigate virulence mechanisms of this pathogen, we studied the toxicity to oysters of its extracellular products (ecps). ecps displayed lethality to animals, with a ld(50) value of 3.3 microg/g body weight. to determine the oyster cellular immune responses induced by these ecps, we further examined in vitro their effects on c. gigas hemocytes, using flow cytometric-based hemocyte assays. ... | 2006 | 16005965 |
| vibrio calviensis sp. nov., a halophilic, facultatively oligotrophic 0.2 microm-fiiterabie marine bacterium. | a gram-negative, facultatively anaerobic, straight to slightly curved rod-shaped bacterium (re35f/12t) sensitive to vibriostatic agent o/129 was previously isolated from sea water (western mediterranean sea, bay of calvi, corsica, france) by 0.2 microm-membrane filtration. strain re35/f12t (= cip 107077t = dsm 14347t) was facultatively oligotrophic, halophilic, required na+ for growth and produced acid but no gas from d-glucose under anaerobic conditions. comparative 165 rrna gene-sequence analy ... | 2002 | 11931167 |
| vibrio scophthalmi sp. nov., a new species from turbot (scophthalmus maximus). | six strains isolated from the intestines of juvenile turbot in a fish hatchery in the north of spain were found to be phenotypically members of the genus vibrio. however, the phenotypic traits of these organisms did not place them in any of the currently known vibrio species. these isolates formed an homogeneous group in which the dna-dna similarity values (the differences between the thermal denaturation midpoints of the homologous and heterologous duplexes) with reference strain a089t (t = typ ... | 1997 | 8995802 |
| nucleotide sequence of the 5s rrna from listonella (vibrio) aestuarianus atcc 35048. | | 1987 | 3822846 |
| mass mortality in bivalves and the intricate case of the pacific oyster, crassostrea gigas. | massive mortality outbreaks in cultured bivalves have been reported worldwide and they have been associated with infection by a range of viral and bacterial pathogens. due to their economic and social impact, these episodes constitute a particularly sensitive issue in pacific oyster (crassostrea gigas) production. since 2008, mortality outbreaks affecting c. gigas have increased in terms of intensity and geographic distribution. epidemiologic surveys have lead to the incrimination of pathogens, ... | 2015 | 26210497 |
| interactions between mytilus galloprovincialis hemocytes and the bivalve pathogens vibrio aestuarianus 01/032 and vibrio splendidus lgp32. | 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 v ... | 2013 | 24080469 |
| vibrio oceanisediminis sp. nov., a nitrogen-fixing bacterium isolated from an artificial oil-spill marine sediment. | a gram-staining-negative, halophilic, facultatively anaerobic, motile, rod-shaped and nitrogen-fixing bacterium, designated strain s37t, was isolated from an artificial oil-spill sediment sample from the coast of taean, south korea. cells grew at 10-37 °c and ph 5.0-9.0, with optimal growth at 28 °c and ph 6.0-8.0. growth was observed with 1-9 % (w/v) nacl in marine broth, with optimal growth with 3-5 % nacl, but no growth was observed in the absence of nacl. according to the results of 16s rrna ... | 2015 | 26296768 |
| genetic parameters of resistance to vibrio aestuarianus, and oshv-1 infections in the pacific oyster, crassostrea gigas, at three different life stages. | in france, two main diseases threaten pacific oyster production. since 2008, crassostrea gigas spat have suffered massive losses due to the ostreid herpesvirus oshv-1, and since 2012, significant mortalities in commercial-size adults have been related to infection by the bacterium vibrio aestuarianus. the genetic basis for resistance to v. aestuarianus and oshv-1 and the nature of the genetic correlation between these two traits were investigated by using 20 half-sib sire families, each containi ... | 2017 | 28201985 |
| can selection for resistance to oshv-1 infection modify susceptibility to vibrio aestuarianus infection in crassostrea gigas? first insights from experimental challenges using primary and successive exposures. | since 2008, the emergent virus oshv-1µvar has provoked massive mortality events in crassostrea gigas spat and juveniles in france. since 2012, mortality driven by the pathogenic bacteria vibrio aestuarianus has stricken market-sized adults. a hypothesis to explain the sudden increase in mortality observed in france since 2012 is that selective pressure due to recurrent viral infections could have led to a higher susceptibility of adults to vibrio infection. in our study, two oshv-1-resistant lin ... | 2015 | 26646058 |
| single or dual experimental infections with vibrio aestuarianus and oshv-1 in diploid and triploid crassostrea gigas at the spat, juvenile and adult stages. | french production of the pacific cupped oyster, crassostrea gigas, is currently threatened by two pathogens, oshv-1 and v. aestuarianus. while oysters selected for their higher resistance to oshv-1 are now available for the industry, the impact of v. aestuarianus on such oysters is unknown, especially for triploids. in addition, experimental infection has used the virus or the bacteria alone, but there have been no investigations of dual exposure to these pathogens. this study is the first repor ... | 2016 | 27503207 |
| killing of vibrio cholerae and escherichia coli strains carrying d-mannose-sensitive ligands by mytilus hemocytes is promoted by a multifunctional hemolymph serum protein. | in aquatic environments, bivalve mollusks represent an important ecological niche for microorganisms. persistence of bacteria in bivalve tissues partly depends on their capacity to survive the bactericidal activity of the hemolymph due to both cellular (hemocyes) and soluble serum factors (e.g., enzymes, lectins, opsonins). the extrapallial protein (ep) present in serum of mytilus galloprovincialis (mgep) has been recently shown to work as an opsonin promoting d-mannose sensitive (ms) interactio ... | 2016 | 27041371 |
| mevalonosomes: specific vacuoles containing the mevalonate pathway in plocamium brasiliense cortical cells (rhodophyta). | this paper has identified, for the first time in a member of the rhodophyta, a vacuolar organelle containing enzymes that are involved in the mevalonate pathway-an important step in red algal isoprenoid biosynthesis. these organelles were named mevalonosomes (mev) and were found in the cortical cells (cc) of plocamium brasiliense, a marine macroalgae that synthesizes several halogenated monoterpenes. p. brasiliense specimens were submitted to a cytochemical analysis of the activity of the 3-hydr ... | 2015 | 26986518 |
| how egg case proteins can protect cuttlefish offspring? | sepia officinalis egg protection is ensured by a complex capsule produced by the female accessory genital glands and the ink bag. our study is focused on the proteins constituting the main egg case. de novo transcriptomes from female genital glands provided essential databases for protein identification. a proteomic approach in sds-page coupled with ms unveiled a new egg case protein family: sepecps, for sepia officinalis egg case proteins. n-glycosylation was demonstrated by pas staining sds-pa ... | 2015 | 26168161 |
| autophagy plays an important role in protecting pacific oysters from oshv-1 and vibrio aestuarianus infections. | recent mass mortality outbreaks around the world in pacific oysters, crassostrea gigas, have seriously affected the aquaculture economy. although the causes for these mortality outbreaks appear complex, infectious agents are involved. two pathogens are associated with mass mortality outbreaks, the virus ostreid herpesvirus 1 (oshv-1) and the bacterium vibrio aestuarianus. here we describe the interactions between these 2 pathogens and autophagy, a conserved intracellular pathway playing a key ro ... | 0 | 25714877 |
| characterization of the secretomes of two vibrios pathogenic to mollusks. | vibrio tapetis causes the brown ring disease in the japanese clam ruditapes philippinarum while vibrio aestuarianus is associated with massive oyster mortalities. as extracellular proteins are often associated with the virulence of pathogenic bacteria, we undertook a proteomic approach to characterize the secretomes of both vibrios. the extracellular proteins (ecps) of both species were fractionated by sec-fplc and in vitro assays were performed to measure the effects of each fraction on hemocyt ... | 2014 | 25401495 |
| first evidence of a potential antibacterial activity involving a laccase-type enzyme of the phenoloxidase system in pacific oyster crassostrea gigas haemocytes. | phenoloxidases (pos) are a group of copper proteins including tyrosinase, catecholase and laccase. in several insects and crustaceans, antibacterial substances are produced through the po cascade, participating in the direct killing of invading microorganisms. however, although pos are widely recognised as an integral part of the bivalve immune defence system, experimental evidence is lacking that these properties are conserved in molluscs, and more particularly in the pacific oyster crassostrea ... | 2011 | 21802516 |
| occurrence and seasonality of vibrio aestuarianus in sediment and crassostrea gigas haemolymph at two oyster farms in france. | vibrio aestuarianus is frequently found in coastal areas and can infect and induce mortalities in the pacific oyster crassostrea gigas. however, nothing is known about its distribution and seasonality in the estuarine environment, especially where oyster farming is practiced. its occurrence was investigated in sediment and oyster haemolymph at 2 oyster farms in brittany (france) over 2 yr during 2 periods, from june to september 2007 and from february to june 2008. total heterotrophic bacteria ( ... | 2010 | 21133321 |
| molecular and phenotypic characterization of vibrio aestuarianus, a pathogen of the cultured tongue sole, cynoglossus semilaevis günther. | studies were conducted to determine the cause of high mortalities of cultured half-smooth tongue sole cynoglossus semilaevis. gross signs of disease included loss of appetite, erratic swimming, and haemorrhages on the head, opercula and base of fins, dorsal fin rot, swollen abdomen filled with ascitic fluid and herniation of the intestine. histological examination of the liver showed focal areas of necrosis and extensive haemorrhages. virtually pure, dense bacterial cultures were obtained from l ... | 2010 | 21118272 |
| responses of diploid and triploid pacific oysters crassostrea gigas to vibrio infection in relation to their reproductive status. | several vibrio species are known to be pathogenic to the pacific oyster crassostrea gigas. survival varies according to pathogen exposure and high mortality events usually occur in summer during gametogenesis. in order to study the effects of gametogenetic status and ploidy (a factor known to affect reproduction allocation in oysters) on vibriosis survival, we conducted two successive experiments. our results demonstrate that a common bath challenge with pathogenic vibrio splendidus and vibrio a ... | 2011 | 20833182 |
| vibrio aestuarianus zinc metalloprotease causes lethality in the pacific oyster crassostrea gigas and impairs the host cellular immune defenses. | 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 r ... | 2010 | 20624467 |
| a large-scale epidemiological study to identify bacteria pathogenic to pacific oyster crassostrea gigas and correlation between virulence and metalloprotease-like activity. | 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 harvey ... | 2010 | 20012275 |
| real-time pcr assay for rapid detection and quantification of vibrio aestuarianus in oyster and seawater: a useful tool for epidemiologic studies. | because vibrio aestuarianus is known to cause serious infections in pacific oyster crassostrea gigas, a real-time pcr assay was developed targeting the dnaj gene of this bacterium. only v. aestuarianus strains isolated from c. gigas mortality events in different geographic areas and the reference strain tested positive, whereas no amplification products was obtained with type strains belonging to 23 other species of vibrio. sensitivity and reproducibility of the method were assessed using either ... | 2009 | 19318049 |
| first isolation of nocardia crassostreae from pacific oyster crassostrea gigas in europe. | in summer 2006 an extensive mortality of pacific oysters crassostrea gigas occurred in lake grevelingen, the netherlands. a sample of pacific oysters was investigated for the presence of shellfish pathogens as potential causes of the mortality. yellow-green lesions were observed in several oysters upon clinical inspection. histopathology showed that 6 out of 36 oysters had a suspected bacterial infection, including 4 nocardia-like infections. two bacterial species, vibrio aestuarianus and nocard ... | 2008 | 18814548 |
| establishment of stable gfp-tagged vibrio aestuarianus strains for the analysis of bacterial infection-dynamics in the pacific oyster, crassostrea gigas. | several marine pathogens are thought to be implicated in the summer mortality phenomenon that strikes the pacific oyster stocks (crassostrea gigas) in europe since more than a decade. although, since 2008, a herpes virus variant (microvar) is considered the main responsible for juvenile mortalities, the role of several associated bacteria is less clear. one of these, vibrio aestuarianus, has often been detected in moribund oysters, and laboratory challenges proved its involvement in oyster death ... | 2013 | 23583012 |
| influence of oyster culture on biogeochemistry and bacterial community structure at the sediment-water interface. | bacterial community structure and some biogeochemical parameters were studied in the sediment of two pacific oyster farming sites, aber benoît (ab) and rivière d'auray (ra) in brittany (france), to examine the ecological impact of oysters and to evaluate the emission of sulfide and ammonia from sediment. at ab, the organic matter accumulated in the sediment beneath the oyster tables was rapidly mineralized, with strong fluxes of ammonia and sulfide that reached 1014 and 215 μmol m(-2) h(-1), res ... | 2012 | 22571367 |
| novel quantitative taqman® mgb real-time pcr for sensitive detection of vibrio aestuarianus in crassostrea gigas. | validation of a novel quantitative real-time pcr using taqman® minor groove binder (mgb) chemistry is described for sensitive and rapid detection of vibrio aestuarianus, an increasingly important pathogen of pacific cupped oyster crassostrea gigas aquaculture. primers and taqman® mgb hydrolysis probe were designed to specifically amplify a 58bp dna fragment of the v. aestuarianus dnaj gene. real-time pcr selectivity was empirically tested using dna extracted from isolates of v. aestuarianus and ... | 2015 | 26036831 |
| vibrio salilacus sp. nov., a new member of the anguillarum clade with six alleles of the 16s rrna gene from a saline lake. | a gram-stain-negative, catalase- and oxidase-positive, facultatively aerobic bacterium, strain dsg-s6t, was isolated from dasugan lake (salinity 3.1%, w/w), china. its taxonomic position was determined by using a polyphasic approach. cells of strain dsg-s6t were non-spore-forming, slightly bent rods, and motile by means of a single polar flagellum. growth occurred in the presence of 0-7.0% (w/v) nacl (optimum, 2.0%), at 4-35 °c (optimum, 30 °c) and at ph 6.0-10.5 (optimum, ph 8.0-8.5). c16 : 0, ... | 2015 | 25964518 |
| susceptibility of vibrio aestuarianus 01/032 to the antibacterial activity of mytilus haemolymph: identification of a serum opsonin involved in mannose-sensitive interactions. | the interactions of vibrio aestuarianus 01/032 with haemolymph of the bivalves mytilus galloprovincialis and crassostrea gigas were investigated to understand if haemolymph components (haemocytes and soluble factors) could be involved in the higher resistance to microbial infection shown by mussels in comparison with oysters. although 01/032 bacteria adhered to haemocytes of both bivalves, they were sensitive to the bactericidal activity of whole haemolymph from mussel, but not from oyster; in a ... | 2015 | 25655520 |
| a single regulatory gene is sufficient to alter vibrio aestuarianus pathogenicity in oysters. | oyster diseases caused by pathogenic vibrios pose a major challenge to the sustainability of oyster farming. in france, since 2012 a disease affecting specifically adult oysters has been associated with the presence of vibrio aestuarianus. here, by combining genome comparison, phylogenetic analyses and high-throughput infections of strains isolated before or during the recent outbreaks, we show that virulent strains cluster into two v. aestuarianus lineages independently of the sampling dates. t ... | 2015 | 25384557 |
| antibiotic resistance of vibrio species isolated from sparus aurata reared in italian mariculture. | extensive use of antimicrobial agents in finfish farming and the consequent selective pressure lead to the acquisition of antibiotic resistance in aquaculture environment bacteria. vibrio genus represents one of the main pathogens affecting gilthead sea bream. the development of antibiotic resistance by vibrio represents a potential threat to human health by exchange of resistant genes to human pathogens through food chain. the objective of the present study was to conduct a multisite survey on ... | 2014 | 25180847 |
| mortality occurrence and pathogen detection in crassostrea gigas and mytilus galloprovincialis close-growing in shallow waters (goro lagoon, italy). | the complex interactions occurring between farmed bivalves and their potential pathogens in the circumstances of global climate changes are current matter of study, owing to the recurrent production breakdowns reported in europe and other regions of the world. in the frame of project fp7-kbbe-2010-4 bivalife, we investigated the occurrence of mortality and potential pathogens during the spring-summer transition in crassostrea gigas and mytilus galloprovincialis cohabiting in the shallow waters o ... | 2014 | 24909498 |
| aquatic ecology of the oyster pathogens vibrio splendidus and vibrio aestuarianus. | 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 ... | 2015 | 24725454 |
| several strains, one disease: experimental investigation of vibrio aestuarianus infection parameters in the pacific oyster, crassostrea gigas. | this study investigated oyster infection dynamics by different strains of vibrio aestuarianus isolated before and after the apparent re-emergence of this pathogen observed in france in 2011. we conducted experiments to compare minimal infective dose, lethal dose 50 and bacterial shedding for six v. aestuarianus strains. whatever the strain used, mortality was induced in juvenile oysters by intramuscular injection and reached 90-100% of mortality within 5 days. moreover, bacterial shedding was co ... | 2017 | 28549482 |
| development of a duplex taqman real-time pcr assay for rapid identification of vibrio splendidus-related and v. aestuarianus strains from bacterial cultures. | to enable the rapid and accurate identification of vibrio splendidus-related and v. aestuarianus strains associated with pacific cupped oyster crassostrea gigas mortality, we developed a duplex taqman real-time pcr assay and evaluated its efficacy. this technique proved to be rapid, sensitive, and specific and will be particularly valuable for epidemiologic studies. | 2017 | 28709898 |
| first description of a mortality event in adult pacific oysters in italy associated with infection by a tenacibaculum soleae strain. | summer mortality episodes in adult pacific oysters have been described since the 1950s in various farming areas. starting in 2012, a recrudescence of mortalities in commercial-sized oysters was first observed in france and then in italy, with seasonality extension and translation later in the year. moribund individuals collected during an event in italy in december 2014 showed yellowish lesions of the mantle and adductor muscle. histological examination revealed filamentous bacteria associated w ... | 2017 | 28836671 |