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Registros recuperados: 22 | |
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Lazar, Cassandre Sara; L'Haridon, Stephane; Pignet, Patricia; Toffin, Laurent. |
Microbial mats in marine cold seeps are known to be associated with ascending sulfide- and methane-rich fluids. Hence, they could be visible indicators of anaerobic oxidation of methane (AOM) and methane cycling processes in underlying sediments. The Napoli mud volcano is situated in the Olimpi Area that lies on saline deposits; from there, brine fluids migrate upward to the seafloor. Sediments associated with a brine pool and microbial orange mats of the Napoli mud volcano were recovered during the Medeco cruise. Based on analysis of RNA-derived sequences, the "active" archaeal community was composed of many uncultured lineages, such as rice cluster V or marine benthic group D. Function methyl coenzyme M reductase (mcrA) genes were affiliated with the... |
Tipo: Text |
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Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00035/14589/12126.pdf |
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Vigneron, Adrien; Cruaud, Perrine; Pignet, Patricia; Caprais, Jean-claude; Gayet, Nicolas; Cambon-bonavita, Marie-anne; Godfroy, Anne; Toffin, Laurent. |
The Sonora Margin cold seeps present on the seafloor a patchiness pattern of white microbial mats surrounded by polychaete and gastropod beds. These surface assemblages are fuelled by abundant organic inputs sedimenting from the water column and upward-flowing seep fluids. Elevated microbial density was observed in the underlying sediments. A previous study on the same samples identified anaerobic oxidation of methane (AOM) as the potential dominant archaeal process in these Sonora Margin sediments, probably catalysed by three clades of archaeal anaerobic methanotrophs (ANME-1, ANME-2 and ANME-3) associated with bacterial syntrophs. In this study, molecular surveys and microscopic observations investigating the diversity of Bacteria involved in AOM... |
Tipo: Text |
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Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00168/27921/27279.pdf |
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Wery, Nathalie; Moricet, Jean-marc; Cueff, Valerie; Jean, Joelle; Pignet, Patricia; Lesongeur, Francoise; Cambon-bonavita, Marie-anne; Barbier, Georges. |
A thermophilic, anaerobic, chemo-organotrophic bacterium, designated MV1087(T), was isolated from a deep-sea hydrothermal chimney sample collected from the Mid-Atlantic Ridge. The cells were straight, motile and stained Gram-negative. Growth was observed from 45 to 65 degreesC, with an optimum around 65 degreesC. No growth was observed at 40 or 70 degreesC. Growth was observed from pH 5.5 to 9.0 and the optimum pH was around 7. The salinity range for growth was 10-100 g sea salt l(-1) (corresponding to 6.5-65 g NaCl l(-1)) with an optimum at 30 g sea salt l(-1) (20 g NaCl l(-1)). Strain MV1087(T) was heterotrophic, able to ferment proteinaceous substrates, such as brain/heart infusion and gluten, and carbohydrates, such as glucose, xylan and starch. The... |
Tipo: Text |
Palavras-chave: Thermophile; Deep sea vent; Caloranaerobacter azorensis; Caloranaerobacter; Bacteria. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-586.pdf |
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Alain, Karine; Pignet, Patricia; Zbinden, M; Quillevere, M; Duchiron, F; Donval, Jean-pierre; Lesongeur, Francoise; Raguenes, Gerard; Crassous, Philippe; Querellou, Joel; Cambon-bonavita, Marie-anne. |
A novel thermophilic, anaerobic, strictly chemoorganoheterotrophic bacterium, designated as AM1114(T), was isolated from a deep-sea hydrothermal vent sample from the East-Pacific Rise (EPR 13degrees N). The cells were long (3-10 mum) rods, motile with peritrichous flagella, and exhibited a Gram-negative cell wall ultrastructure. In the late stationary phase of growth, cells formed an ovoid, refractile, terminal endospore. They grew at 45-65 degreesC inclusive (optimum 55-60 degreesC; doubling time approx. 45 min), at pH 4.5-8.0 inclusive (optimum pH 7.5-8.0) and at sea salt concentrations of 20-60 g l(-1) inclusive (optimum 25-30 g l(-1)). Strain AM1114(T) was an obligately heterotrophic bacterium able to ferment a mixture of 20 amino acids, complex... |
Tipo: Text |
Palavras-chave: Caminicella sporogenes; Clostridiales; Thermophile; Deep sea hydrothermal vent. |
Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/2002/publication-528.pdf |
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Cruaud, Perrine; Vigneron, Adrien; Pignet, Patricia; Caprais, Jean-claude; Lesongeur, Francoise; Toffin, Laurent; Godfroy, Anne; Cambon-bonavita, Marie-anne. |
In the Guaymas Basin, the presence at a few tens of kilometers of cold seeps and hydrothermal vents coupled with comparable sedimentary settings and depths offer a unique opportunity to assess and compare the microbial community composition of these deep-sea ecosystems. The microbial diversity in sediments from three cold seep and two hydrothermal vent assemblages were investigated using high-throughput 16S rRNA-sequencing. Numerous bacterial and archaeal lineages were detected in both cold seep and hydrothermal vent sediments. Various potential organic matter degraders (e.g., Chloroflexi, Atribacteria, MBG-D) and methane and sulfur cycling related microorganisms (e.g., ANME and methanogenic lineages, sulfate-reducing lineages) were detected in both... |
Tipo: Text |
Palavras-chave: Microbial diversity; Hydrothermal vents; Cold seeps; Ribotypes; Methane; Extreme environments. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00415/52640/53496.pdf |
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Postec, Anne; Lesongeur, Francoise; Pignet, Patricia; Ollivier, B; Querellou, Joel; Godfroy, Anne. |
The prokaryotic diversity of culturable thermophilic communities of deep-sea hydrothermal chimneys was analysed using a continuous enrichment culture performed in a gas-lift bioreactor, and compared to classical batch enrichment cultures in vials. Cultures were conducted at 60 degrees C and pH 6.5 using a complex medium containing carbohydrates, peptides and sulphur, and inoculated with a sample of a hydrothermal black chimney collected at the Rainbow field, Mid-Atlantic Ridge, at 2,275 m depth. To assess the relevance of both culture methods, bacterial and archaeal diversity was studied using cloning and sequencing, DGGE, and whole-cell hybridisation of 16S rRNA genes. Sequences of heterotrophic microorganisms belonging to the genera Marinitoga,... |
Tipo: Text |
Palavras-chave: Metabolic interactions; 16S rRNA gene; Thermophiles; Bioreactor; Continuous enrichment cultures; Deep sea hydrothermal vent; Microbial diversity. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3885.pdf |
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Cruaud, Perrine; Decker, Carole; Olu, Karine; Arnaud-haond, Sophie; Papot, Claire; Le Baut, Jocelyn; Vigneron, Adrien; Khripounoff, Alexis; Gayet, Nicolas; Cathalot, Cecile; Caprais, Jean-claude; Pignet, Patricia; Godfroy, Anne; Cambon Bonavita, Marie-anne. |
This study provides an analysis of vesicomyid bivalve–symbiont community distribution across cold seep and hydrothermal vent areas in the Guaymas Basin (Gulf of California, Mexico). Using a combination of morphological and molecular approaches including fluorescent in situ hybridization (FISH), and electronic microscopy observations, vesicomyid clam species and their associated symbionts were characterized and results were analyzed in light of geochemical conditions and other on‐site observations. A greater diversity of vesicomyids was found at cold seep areas, where three different species were present (Phreagena soyoae [syn. kilmeri], Archivesica gigas, and Calyptogena pacifica). In contrast, A. gigas was the only species sampled across the hydrothermal... |
Tipo: Text |
Palavras-chave: Deep-sea ecosystems; Guaymas Basin; Marine ecology; Pliocardinae bivalve; Sulfur storage; Vesicomyid movements. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00493/60426/64028.pdf |
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Ruffine, Livio; Caprais, Jean-claude; Bayon, Germain; Riboulot, Vincent; Donval, Jean-pierre; Etoubleau, Joel; Birot, Dominique; Pignet, Patricia; Rongemaille, Emmanuelle; Chazallon, Bertrand; Grimaud, Sylvie; Adamy, Jerome; Charlou, Jean-luc; Voisset, Michel. |
A joint industrial project with IFREMER and Total provides insights into the tectonic setting and the geochemistry of a large active pockmark offshore W-Africa in the Niger Delta. The study combines both geophysical (seismic) and geochemical data to infer the dynamics of a 300 m wide pockmark located at 667 m water depth. Two Calypso cores, one at the centre and one outside the pockmark, along with three box-cores, two inside the pockmark and one outside, were collected to study the geochemistry of gas hydrates, carbonates and pore waters. Two seismic lines, a 3D high resolution random line and a 2D high resolution seismic line, provide a good description of the plumbing of the system. The integrated results depict a very active pockmark characterized by... |
Tipo: Text |
Palavras-chave: Active pockmark; Anaerobic oxidation of methane; Gas hydrates; Carbonates; Seismic surveys; Fault system; U/Th dating. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00139/24981/23102.pdf |
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Toffin, Laurent; Zink, Klaus; Kato, Chiaki; Pignet, Patricia; Bidault, Adeline; Bienvenu, Nadège; Birrien, Jean-louis; Prieur, Daniel. |
A piezotolerant, mesophilic, marine lactic acid bacterium (strain LT20(T)) was isolated from a deep sub-seafloor sediment core collected at Nankai Trough, off the coast of Japan. Cells were Gram-positive, rod-shaped, non-sporulating and non-motile. The NaGl concentration range for growth was 0-120 gl(-1), with the optimum at 10-20 g l(-1). The temperature range for growth at PH 7.0 was 4-50 degreesC, with the optimum at 37-40 degreesC. The optimum pH for growth was 7.0-8.0. The optimum pressure for growth was 0.1 MPa with tolerance up to 30 MPa. The main cellular phospholipids were phosphatidylglycerols (25 %), diphosphatidylglycerols (34 %) and a group of compounds tentatively identified as ammonium-containing phosphatidylserines (32 %);... |
Tipo: Text |
Palavras-chave: Phylogeny; Biochemistry; Microbiology; Thermophilic bacteria; Deep sub seafloor sediment. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-592.pdf |
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Wery, Nathalie; Lesongeur, Francoise; Pignet, Patricia; Derennes, Veronique; Cambon-bonavita, Marie-anne; Godfroy, Anne; Barbier, Georges. |
A thermophilic, anaerobic, chemo-organotrophic sulfur-reducing bacterium, designated MV1075(T), was isolated from a deep-sea hydrothermal chimney sample collected on the Mid-Atlantic Ridge. Cells were rod-shaped with a sheath-like outer structure, motile with polar flagella and stained Gramnegative. They appeared singly, in pairs or in short chains. The temperature range for growth was 25-65 degreesC, with an optimum at 55 degreesC. Growth was observed from ph 5 to ph 9, and the optimum ph was around 7. The salinity range for growth was 15-70 g sea salt I-1 (corresponding to 10-45 g NaCl I-1), with an optimum at 30 g I-1 (20 g NaCl I-1). The isolate was able to grow on a broad spectrum of carbohydrates or complex proteinaceous substrates. Sulfur was not... |
Tipo: Text |
Palavras-chave: Marinitoga camini; Thermotogales; Thermophile; Deep sea hydrothermal vent. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-587.pdf |
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Postec, Anne; Le Breton, Claire; Fardeau, Marie-laure; Lesongeur, Francoise; Pignet, Patricia; Querellou, Joel; Ollivier, Bernard; Godfroy, Anne. |
A novel, thermophilic, anaerobic bacterium that is able to tolerate hydrogen was isolated from a deep-sea hydrothermal chimney collected at the Rainbow field on the Mid-Atlantic Ridge. Cells were rod-shaped and surrounded by a sheath-like outer structure (toga); they were weakly motile by means of a polar flagellum. They appeared singly, in pairs or in short chains. They grew at 35-65 degrees C (optimum 60 degrees C), pH 4.5-8.5 (optimum pH 6.0) and 10-65 g sea salts l(-1) (optimum 30-40 g l(-1)). The isolate was organotrophic, and able to grow on various carbohydrates or complex proteinaceous substrates. Growth was not inhibited under 100% hydrogen or in the presence of 2% oxygen in the gas phase. The isolate reduces sulfur, although sulfur reduction is... |
Tipo: Text |
Palavras-chave: Anaerobic bacterium; Marinitoga hydrogenitolerans; Thermotogales; Thermophile; Deep sea vent. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-363.pdf |
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Cruaud, Perrine; Vigneron, Adrien; Pignet, Patricia; Caprais, Jean-claude; Lesongeur, Francoise; Toffin, Laurent; Godfroy, Anne; Cambon-bonavita, Marie-anne. |
The Sonora Margin cold seeps present a seafloor mosaic pattern consisting of different faunal assemblages and microbial mats. To better understand if sedimentary microbial communities reflect this patchy distribution, all major habitats were investigated using four complementary approaches: 16S rRNA gene sequence 454 pyrosequencing, quantitative polymerase chain reaction, fluorescence in situ hybridization and geochemistry analyses. This study reveals that sediments populated by different surface assemblages show distinct porewater geochemistry features and are associated with distinct microbial communities. In the sediments underlying the microbial mat and the surrounding macrofauna, microbial communities were dominated by anaerobic methane oxidizers... |
Tipo: Text |
Palavras-chave: Microbial communities; Pyrosequencing; MBG-D; ANME; Faunal assemblages; Vesicomyidae; Siboglinidae; Microbial mat. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00288/39889/38434.pdf |
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Postec, Anne; Pignet, Patricia; Cueff-gauchard, Valerie; Schmitt, Anne; Querellou, Joel; Godfroy, Anne. |
The hyperthermophilic archaeon Thermococcus hydrothermalis was cultivated in continuous culture in a gas-lift bioreactor in the absence of elemental sulphur on both proteinaceous and maltose-containing media. Optimal conditions (pH, temperature and gas flow rate), determined on complex media that yielded maximal growth rate and maximal steady state cell density, were obtained at 80degreesC, pH 6 and gas sparging at 0.2 v v(-1) min(-1). Higher steady state cell densities were obtained on a medium containing maltose and yeast extract. In order to design a defined and minimal media, the nutritional requirements of T hydrothermalis were then investigated using continuous culture in the absence of elemental sulphur in the gas-lift bioreactor. First, the complex... |
Tipo: Text |
Palavras-chave: Bioreactor; Defined and minimal media; Culture optimisation; Gas lift bioreactor; Thermococcus hydrothermalis. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-365.pdf |
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Boulais, Myrina; Suquet, Marc; Arsenault-pernet, Marie Eve Julie; Malo, Florent; Queau, Isabelle; Pignet, Patricia; Ratiskol, Dominique; Le Grand, Jacqueline; Huber, Matthias; Cosson, Jacky. |
Investigating the roles of chemical factors stimulating and inhibiting sperm motility is required to understand the mechanisms of spermatozoa movement. In this study, we described the composition of the seminal fluid (osmotic pressure, pH, and ions) and investigated the roles of these factors and salinity in initiating spermatozoa movement in the Pacific oyster. The acidic pH of the gonad (5.82 ± 0.22) maintained sperm in the quiescent stage and initiation of flagellar movement was triggered by a sudden increase of spermatozoa external pH (pHe) when released in seawater (SW). At pH 6.4, percentage of motile spermatozoa was three times higher when they were activated in SW containing 30 mM NH4Cl, which alkalinizes internal pH (pHi) of spermatozoa, compared... |
Tipo: Text |
Palavras-chave: Seminal fluid; Spermatozoa; Motility; PH; Salinity; Ions. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00428/53976/55137.pdf |
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Vigneron, Adrien; Cruaud, Perrine; Roussel, Erwan; Pignet, Patricia; Caprais, Jean-claude; Callac, Nolwenn; Ciobanu, Maria Cristina; Godfroy, Anne; Cragg, Barry A.; Parkes, John R.; Van Nostrand, Joy D.; He, Zhili; Zhou, Jizhong; Toffin, Laurent. |
Subsurface sediments of the Sonora Margin (Guaymas Basin), located in proximity of active cold seep sites were explored. The taxonomic and functional diversity of bacterial and archaeal communities were investigated from 1 to 10 meters below the seafloor. Microbial community structure and abundance and distribution of dominant populations were assessed using complementary molecular approaches (Ribosomal Intergenic Spacer Analysis, 16S rRNA libraries and quantitative PCR with an extensive primers set) and correlated to comprehensive geochemical data. Moreover the metabolic potentials and functional traits of the microbial community were also identified using the GeoChip functional gene microarray and metabolic rates. The active microbial community structure... |
Tipo: Text |
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Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00203/31408/29801.pdf |
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Ciobanu, Maria Cristina; Rabineau, Marina; Droz, Laurence; Revillon, Sidonie; Ghiglione, J. -f.; Dennielou, Bernard; Jorry, Stephan; Kallmeyer, J.; Etoubleau, Joel; Pignet, Patricia; Crassous, Philippe; Vandenabeele-trambouze, Odile; Laugier, J.; Guegan, Matthieu; Godfroy, Anne; Alain, Karine. |
An interdisciplinary study was conducted to evaluate the relationship between geological and paleoenvironmental parameters and the bacterial and archaeal community structure of two contrasting subseafloor sites in the Western Mediterranean Sea (Ligurian Sea and Gulf of Lion). Both depositional environments in this area are well-documented from paleoclimatic and paleooceanographic point of views. Available data sets allowed us to calibrate the investigated cores with reference and dated cores previously collected in the same area, and notably correlated to Quaternary climate variations. DNA-based fingerprints showed that the archaeal diversity was composed by one group, Miscellaneous Crenarchaeotic Group (MCG), within the Gulf of Lion sediments and of nine... |
Tipo: Text |
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Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00090/20171/17826.pdf |
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Toffin, Laurent; Bidault, Adeline; Pignet, Patricia; Tindall, Brian; Slobodkin, Alexander; Kato, Chiaki; Prieur, Daniel. |
A novel piezotolerant, mesophilic, facultatively anaerobic, organotrophic, polarly flagellated bacterium (strain LT13a(T)) was isolated from a deep sediment layer in the Nankai Trough (Leg 190, Ocean Drilling Program) off the coast of Japan. This organism used a wide range of organic substrates as sole carbon and energy sources: pyruvate, glutamate, succinate, fumarate, lactate, citrate, peptone and tryptone. Oxygen, nitrate, fumarate, ferric iron and cystine were used as electron acceptors. Maximal growth rates were observed at a hydrostatic pressure of 10 MPa. Hydrostatic pressure for growth was in the range 0.1-50 MPa. Predominant cellular fatty acids were 16:1 omega7c, 15: 0 iso, 16: 0 and 13: 0 iso. The G + C content of the DNA was 44.9 mol%. On the... |
Tipo: Text |
Palavras-chave: Phylogeny; Bacteria; Microbiology; Deep sediment layer. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-590.pdf |
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Bodennec, Guy; Pignet, Patricia; Caprais, Jean-claude. |
A la suite du naufrage du pétrolier Tanio, le 7 mars 1980, l'équipe Chimie du Département ELGMM/COB a participé à différentes campagnes océanographiques et de terrain, principalement dans le secteur compris entre les baies de Lannion et de St Brieuc, pour : 1°) Evaluer le degré de contamination de l'eau de mer et des sédiments subtidaux, 2°) Suivre le processus de dégradation du pétrole piégé à la côte, suivant la nature sédimentologique et la situation géographique du site de prélèvement. Ce rapport complète les précédents compte-rendus de mission, en rassemblant les résultats acquis au cours d'un suivi chimique effectué entre les mois de mars et de juin 1980 pour suivre la cinétique de décontamination de l'eau, et entre les mois de mars 1980 et juillet... |
Tipo: Text |
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Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/00081/19229/16824.pdf |
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Urios, Laurent; Cueff, Valerie; Pignet, Patricia; Barbier, Georges. |
A novel anaerobic, Gram-positive, sporulating and strictly chemoorganoheterotrophic bacterium, designated strain DV1 184 T, was isolated from a deep-sea hydrothermal vent sample from the Mid-Atlantic Ridge. The cells were short, straight rods (4 mum long and 0.8 mum wide) and were motile with peritrichous flagella. They grew between 35 and 55 degreesC (optimum, 45 degreesC), between pH 5.0 and 8.0 (optimum, 6.0) and at 20-60 g sea salts l(-1) (optimum sea salts concentration, 30 g l(-1)). Strain DV1184(T) was able to ferment yeast extract, tryptone, peptone, glucose, sucrose, maltose and pyruvate. The main fermentation products from glucose were (in decreasing order) formate, acetate and ethanol. The genomic DNA G+C content was 29 mol%. Phylogenetic... |
Tipo: Text |
Palavras-chave: Phylogeny; Bacteria; Deep sea hydrothermal vent. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-589.pdf |
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Registros recuperados: 22 | |
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