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Registros recuperados: 73 | |
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Schikorski, David; Renault, Tristan; Paillard, Christine; Bidault-toffin, A.; Tourbiez, Delphine; Saulnier, Denis. |
The Gram-negative bacterium Vibrio harveyi is known to be highly pathogenic for the European abalone Haliotis tuberculata, which is a gastronomically important marine gastropod with a high commercial value. Since 1998, some particular bacterial strains are described as implicated in recurrent mortality outbreaks in French farm and field stocks of abalone. Recently, a 9.6kb plasmid named pVCR1, was shown to be harbored by one highly V. harveyi virulent ORM4 strain suggesting its involvement in virulence phenotype. Thus, we have developed in the present study two TaqMan real-time PCR assays allowing to (i) rapidly and specifically detect, by a duplex procedure and in less than 2 h, both V. harveyi and the presence of plasmid pVCR1 from unidentified bacterial... |
Tipo: Text |
Palavras-chave: Vibrio harveyi; Haliotis tuberculata; Real-time PCR; Plasmid; Marine pathogen; Molecular diagnostic. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00124/23540/21383.pdf |
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Latchere, Oihana; Fievet, Julie; Lo, Cedrik; Schneider, Denis; Dieu, Stephanie; Cabral, Philippe; Belliard, Corinne; Ky, Chin-long; Gueguen, Yannick; Saulnier, Denis. |
The present study investigated the effect of electrolysis on the biomineralization capacities of juveniles of the mollusk Pinctada margaritifera for the first time. Size-selected individuals from two groups, “Medium” and “Large”, from a multi-parental family produced in a hatchery system were subjected to electrolysis under a low voltage current over a nine-week experimental period. The growth of the juveniles was individually monitored and assessed weekly by wet weight and shell height measurements. At the end of the experiment, mantle tissue was sampled for biomineralization-related gene expression analysis. Electrolysis significantly increased pearl oyster growth in terms of shell height and wet weight for Large juveniles from the 5th and the 2nd week,... |
Tipo: Text |
Palavras-chave: Pearl oyster; Pinctada margaritifera; Electrolysis; Biomineralization; Gene expression. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00343/45410/44924.pdf |
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Reverter, Miriam; Saulnier, Denis; David, Rarahu; Bardon-albaret, Agnes; Belliard, Corinne; Tapissier-bontemps, Nathalie; Lecchini, David; Sasal, Pierre. |
The emerging orbicular batfish (Platax orbicularis) aquaculture is the most important fish aquaculture industry in French Polynesia. However, bacterial infections are causing severe mortality episodes. Therefore, there is an urgent need to find an effective management solution. Besides the supplying difficulty and high costs of veterinary drugs in French Polynesia, batfish aquaculture takes place close to the coral reef, where use of synthetic persistent drugs should be restricted. Medicinal plants and bioactive algae are emerging as a cheaper and more sustainable alternative to chemical drugs. We have studied the effect of local Polynesian plants and the local opportunistic algae Asparagopsis taxiformis on batfish when orally administered. Weight gain and... |
Tipo: Text |
Palavras-chave: Orbicular batfish; Asparagopsis taxiformis; Immunostimulant; Lysozyme G; Transforming growth factor; Relative gene expression. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00350/46155/45853.pdf |
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Saulnier, Denis; Reynaud, Yann; Arzul, Isabelle; Miossec, Laurence; Le Roux, Frédérique; Goarant, Cyrille. |
According to the world organisation for animal health (OIE) an emerging disease is defined as a recently admitted serious illness, whose aetiology can, or not, have already been established, and which is likely to be propagated within a population or between populations, for example at the time of international exchanges of aquatic animals and/or products of aquatic animals. Even though the emerging diseases that affect human health have been much studied, those which affect marine organisms and species of aquaculture interest in particular are poorly documented. By restricting emergence to only infectious diseases, we aim at presenting in a non-exhaustive way some scenarios of the emergence of the diseases of aquacultured species by illustrating them with... |
Tipo: Text |
Palavras-chave: Cyprinus carpio; Ostrea edulis; Bonamia ostreae; Peneides; Vibrio nigripulchritudo; Herpesvirus; Agent pathogène. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2980.pdf |
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Schikorski, David; Renault, Tristan; Saulnier, Denis; Faury, Nicole; Moreau, Pierrick; Pepin, Jean-francois. |
In 2008 and 2009, acute mortalities occurred in France among Pacific cupped oyster, Crassostrea gigas, spat. Different hypothesis including the implication of environmental factors, toxic algae and/or pathogens have been explored. Diagnostic tests indicated that OsHV-1 including a particular genotype, termed OsHV-1 mu Var, was detected in most of samples and especially in moribund oysters with the highlighting of virus particles looking like herpes viruses by TEM examination. In this study, an experimental protocol to reproduce OsHV-1 infection in laboratory conditions was developed. This protocol was based on the intramuscular injection of filtered (0.22 mu m) tissue homogenates prepared from naturally OsHV-1 infected spat collected on French coasts... |
Tipo: Text |
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Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00037/14795/12104.pdf |
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Mersni-achour, Rachida; Ben Cheikh, Yosra; Pichereau, Vianney; Doghri, Ibtissem; Etien, Cedric; Degremont, Lionel; Saulnier, Denis; Fruitier-arnaudin, Ingrid; Travers, Marie-agnes. |
Vibrio tubiashii is a marine pathogen isolated from larval and juvenile bivalve molluscs causing bacillary necrosis. Recent studies demonstrated the isolation of this species in a French experimental hatchery/nursery affecting Crassostrea gigas spat in 2007. Here, using larvae of C. gigas as an interaction model, we showed that the French V. tubiashii is virulent to larvae and can cause bacillary necrosis symptoms with a LD50 about 2.3 × 103 cfu ml-1 after 24 h. Moreover, complete or GP- HPLC fractionated extracellular products (ECPs) of this strain appeared toxic to larvae. MS-MS analysis of the different ECPs fractions revealed the existence of an extracellular metalloprotease and other suspected virulence factors. This observation is also supported by... |
Tipo: Text |
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Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00252/36367/34907.pdf |
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Travers, Marie-agnes; Mersni Achour, Rachida; Haffner, Philippe; Tourbiez, Delphine; Cassone, Anne-laure; Morga, Benjamin; Doghri, Ibtissem; Garcia, Celine; Renault, Tristan; Fruitier-arnaudin, Ingrid; Saulnier, Denis. |
Nine dominant bacterial isolates were obtained from different batches of Crassostrea gigas spat experiencing high mortality rates in a French experimental hatchery/nursery in 2007. Using phenotypic analysis combined with multilocus sequence analysis, the isolates were shown to be genetically close to the Vibrio tubiashii type strain. Based on (1) analyses of the recA gene sequences; (2) the results of DNA–DNA hybridization assays between 07/118 T2 (LMG 27884 = CECT 8426), which is a representative strain, and the V. tubiashii type strain (69%); and (3) phenotypic traits, the bacteria were classified in a group close to American V. tubiashii strain. Its virulence (70% of mortalities) and the toxicity of the extracellular products of 07/118 T2 was... |
Tipo: Text |
Palavras-chave: Crassostrea gigas Pathogenicity Extracellular products Polyphasic approach; Real time PCR. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00189/30028/28743.pdf |
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Mersni Achour, Rachida; Imbert-auvray, Nathalie; Huet, Valerie; Ben Cheick, Yosra; Faury, Nicole; Doghri, Ibtissem; Rouatbi, Sonia; Bordenave, Stéphanie; Travers, Marie-agnes; Saulnier, Denis; Fruitier-arnaudin, Ingrid. |
Extracellular products (ECPs) of the French V. tubiashii strain 07/118 T2 were previously reported to be toxic for the Pacific oyster Crassostrea gigas. In this study we now assessed host cellular immune responses and bacterial potential effectors by which these ECPs can be associated with host damages. The adhesion capacity (28% inhibition) and phagocytosis ability (56% inhibition) of oyster hemocytes were the main functions affected following in vitro contact between hemocytes and V. tubiashii ECPs. This may be linked to the demonstration of the capability of ECPs to cleave various cellular substrates as oyster collagen. Moreover, a strong metalloproteolytic activity was recorded with general (azocasein) and specific (ADAM) substrates and characterized... |
Tipo: Text |
Palavras-chave: ECPs; Oyster immune responses; Thermolysin-metalloprotease; Mass spectroscopy; ADAM substrate; Vibrio. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00211/32203/30642.pdf |
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Luna-acosta, Andrea; Saulnier, Denis; Pommier, Mylene; Haffner, Philippe; De Decker, Sophie; Renault, Tristan; Thomas-guyon, Helene. |
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 invertebrate immune defence system, experimental evidence is lacking that these properties are conserved in molluscs, and more particularly in the Pacific oyster Crassostrea gigas. In the present study, Vibrio splendidus LGP32 and Vibrio aestuarianus 02/041 growths were affected, after being treated with C. gigas haemocyte lysate supernatant (HLS), and either a common substrate of POs, l-3,4-dihydroxyphenylalanine (l-DOPA), to... |
Tipo: Text |
Palavras-chave: Phenoloxidases; Antibacterial activity; Vibrio; Bivalve; Immunity. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00045/15598/13001.pdf |
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De Decker, Sophie; Reynaud, Yann; Saulnier, Denis. |
The aim of that studywas to explore the hypothesis that a quorumsensingmechanismmodulatesmetalloprotease gene expression of two Vibrio species pathogenic for oyster, at intraspecific (Vibrio splendidus) and interspecific (V. splendidus affecting V. aestuarianus) levels. Metalloprotease activities (Vsm for V. splendidus LGP32 and Vam for V. aestuarianus 02/041) and growth curves obtained by real-time PCR assay revealed cell density-dependent metalloprotease inductions triggered between 12 h and 16 h of culture. A quorum sensing assay was then developed using a conditioned medium prepared from supernatant of a mutant strain of V. splendidus LGP32 unable to produce metalloprotease. Specific real-time qPCR assays targeting metalloprotease genes vsm and vam... |
Tipo: Text |
Palavras-chave: Quorum sensing; Crassostrea gigas; Vibrio; Metalloprotease; Gene expression. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00124/23539/21381.pdf |
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Bridel, Sébastien; Bourgeon, Frédéric; Marie, Arnaud; Saulnier, Denis; Pasek, Sophie; Nicolas, Pierre; Bernardet, Jean-françois; Duchaud, Eric. |
Tenacibaculum maritimum is responsible for tenacibaculosis, a devastating marine fish disease. This filamentous bacterium displays a very broad host range and a worldwide geographical distribution. We analyzed and compared the genomes of 25 T. maritimum strains, including 22 newly draft-sequenced genomes from isolates selected based on available MLST data, geographical origin and host fish. The genome size (~3.356 Mb in average) of all strains is very similar. The core genome is composed of 2116 protein-coding genes accounting for ~75% of the genes in each genome. These conserved regions harbor a moderate level of nucleotide diversity (~0.0071 bp−1) whose analysis reveals an important contribution of recombination (r/m ≥ 7) in the evolutionary process of... |
Tipo: Text |
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Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00630/74174/73747.pdf |
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Le Roux, Frederique; Zouine, Mohamed; Chakroun, Nesrine; Binesse, Johan; Saulnier, Denis; Bouchier, Christiane; Zidane, Nora; Ma, Laurence; Rusniok, Christophe; Lajus, Aurelie; Buchrieser, Carmen; Medigue, Claudine; Polz, Martin F.; Mazel, Didier. |
P>Vibrio splendidus is a dominant Vibrio species in seawater presenting a remarkable genetic diversity; several strains have been linked to invertebrate's mortality. We report the complete genome sequence of V. splendidus LGP32, an oyster pathogen, and its comparison with partial genome sequences from related strains. As is typical for the genus, V. splendidus LGP32 contains two chromosomes (3.29 and 1.67 Mb) and most essential cellular processes are encoded by chromosome 1. Comparison with two other V. splendidus partial genome sequences (strains 12B01 and Med222) confirms the previously suggested high genotypic diversity within this species and led to the identification of numerous strain-specific regions that could frequently not be assigned to a... |
Tipo: Text |
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Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6632.pdf |
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Vonau, Vincent; Rouxel, Catherine; Saulnier, Denis; Cochennec-laureau, Nathalie; Nedelec, Georges; Goyard, Emmanuel. |
The tropical seabass Lates calcarifer was introduced in Tahiti in 1984 and then was domesticated without other introduction. Three successive generations have been obtained in captivity. Tissue samples of the 38 animaIs which represent the total Tahitian broodstock were preserved in alcohol to be genotyped with four microsatellite markers (Yue et al., 2001). Three of four described markers were successfully transferred to the laboratory of genetics of Tahiti (marker LcaM01, LcaM02, LcaM03), as the revelation technology available locally did not allow the use of LcaM04 in routine. The results show that the genetic diversity of the tahitian broodstock is not equivalent of the one of the species, which could be explained by the small size of the founder... |
Tipo: Text |
Palavras-chave: Lates calcarifer; Marqueurs microsatellites; Reproducteurs; Variabilité génétique; Lates calcarifer; Microsatellite markers; Breeding stock; Genetic diversity. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00142/25300/23372.pdf |
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Lemer, Sarah; Saulnier, Denis; Gueguen, Yannick; Planes, Serge. |
Background: Color polymorphism in the nacre of pteriomorphian bivalves is of great interest for the pearl culture industry. The nacreous layer of the Polynesian black-lipped pearl oyster Pinctada margaritifera exhibits a large array of color variation among individuals including reflections of blue, green, yellow and pink in all possible gradients. Although the heritability of nacre color variation patterns has been demonstrated by experimental crossing, little is known about the genes involved in these patterns. In this study, we identify a set of genes differentially expressed among extreme color phenotypes of P. margaritifera using a suppressive and subtractive hybridization (SSH) method comparing black phenotypes with full and half albino individuals.... |
Tipo: Text |
Palavras-chave: Differential expression; Biomineralization; Nacre; Pearl; Pigmentation; Albino. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00275/38627/37167.pdf |
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Le Moullac, Gilles; Soyez, Claude; Vidal-dupiol, Jeremie; Belliard, Corinne; Fievet, Julie; Sham-koua, Manaarii; Lo-yat, Alain; Saulnier, Denis; Gaertner-mazouni, N.; Gueguen, Yannick. |
The possible consequences of acidification on pearl farming are disruption of oyster metabolism and change in growth. In the laboratory, we studied the impact of pCO2 (3540, 1338 and 541μatm) on the physiology of pearl oysters exposed for 100 days. This experiment was repeated after an interval of one year. Several physiological compartments were examined in pearl oysters: the scope for growth by measuring ingestion, assimilation and oxygen consumption, gametogenesis by means of histological observations, shell growth by measurement and observation by optical and electronic microscopy, and at molecular level by measuring the expression of nine genes of mantle cells implied in the biomineralisation process. Results from both experiments showed that high... |
Tipo: Text |
Palavras-chave: Global change; Pearl oyster; Bioenergetic; Biomineralization; Pacific Ocean; French Polynesia. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00321/43189/42737.pdf |
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Le Moullac, Gilles; Schuck, Lucie; Chabrier, Sebastien; Belliard, Corinne; Lyonnard, Pierre; Broustal, Floriane; Soyez, Claude; Saulnier, Denis; Brahmi, Chloe; Ky, Chin-long; Beliaeff, Benoit. |
The objective of this study was to observe the impact of temperature on pearl formation using an integrative approach describing the rotation of the pearls, the rate of nacre deposition, the thickness of the aragonite tablets and the biomineralizing potential of the pearl sac tissue though the expression level of some key genes. Fifty pearl oysters were grafted with magnetized nuclei to allow the rotation of the pearls to be described. Four months later, 32 of these pearl oysters were exposed to four temperatures (22, 26, 30 and 34°C) for 2 weeks. Results showed that the rotation speed differed according to the movement direction: pearls with axial movement (AM) had a significantly higher rotation speed than those with random movement (RM). Pearl... |
Tipo: Text |
Palavras-chave: Magnetometer; Rotation speed; Nacre growth; Nacre thickness; Gene expression; Pmarg-Pif177. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00450/56196/57753.pdf |
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Registros recuperados: 73 | |
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