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| Registros recuperados: 42 | |
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| Guezennec, Jean; Rimbault, A; Godfroy, Anne; Fromage, M; Marec, F; Rocchiocioli, F. |
| The existence of deep-sea hydrothermal thermophilic archaebacteria raises interesting questions about their metabolism and metabolic products both in a natural environment and in a culture medium. Moreover, the use of these microorganisms as a potential source of molecules of biotechnological interest must be considered, in the light of the fact that metabolic produits can enhance the risk of microbially-induced corrosion. Organic acids formed by an anaerobic thermophilic sulphur-dependent archaebacterium were analysed as tert-butyldimethylsilyl derivatives by GC and GC/MS. Data indicated the presence in significant amounts of propanoic, 2-methyl propanoic, 3-(methylthio) propanoic, phenylacetic and 4-hydroxyphenylacetic acids. In addition, the use of... |
| Tipo: Text |
Palavras-chave: ARCHAEA; ORGANIC ACIDS; AMINO ACIDS; LABELED ISOTOPES. |
| Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/00099/21011/18637.pdf |
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| Pluchon, Pierre Francois; Fouqueau, Thomas; Creze, Christophe; Laurent, Sebastien; Briffotaux, Julien; Hogrel, Gaelle; Palud, Adeline; Henneke, Ghislaine; Godfroy, Anne; Hausner, Winfried; Thomm, Michael; Nicolas, Jacques; Flament, Didier. |
| In Archaea, the proteins involved in the genetic information processing pathways, including DNA replication, transcription, and translation, share strong similarities with those of eukaryotes. Characterizations of components of the eukaryotic-type replication machinery complex provided many interesting insights into DNA replication in both domains. In contrast, DNA repair processes of hyperthermophilic archaea are less well understood and very little is known about the intertwining between DNA synthesis, repair and recombination pathways. The development of genetic system in hyperthermophilic archaea is still at a modest stage hampering the use of complementary approaches of reverse genetics and biochemistry to elucidate the function of new candidate DNA... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00171/28198/26556.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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| 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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| Portail, Marie; Olu, Karine; Escobar-briones, E.; Caprais, Jean-claude; Menot, Lenaick; Waeles, Mathieu; Cruaud, Perrine; Sarradin, Pierre-marie; Godfroy, Anne; Sarrazin, Jozee. |
| Understanding the ecological processes and connectivity of chemosynthetic deep-sea ecosystems requires comparative studies. In the Guaymas Basin (Gulf of California, Mexico), the presence of seeps and vents in the absence of a biogeographic barrier, and comparable sedimentary settings and depths offers a unique opportunity to assess the role of ecosystem-specific environmental conditions on macrofaunal communities. Six seep and four vent assemblages were studied, three of which were characterised by common major foundation taxa: vesicomyid bivalves, siboglinid tubeworms and microbial mats. Macrofaunal community structure at the family level showed that density, diversity and composition patterns were primarily shaped by seep- and vent-common abiotic... |
| Tipo: Text |
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| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00280/39076/37642.pdf |
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| Postec, Anne; Urios, Laurent; Lesongeur, Francoise; Ollivier, Bernard; Querellou, Joel; Godfroy, Anne. |
| The microflora developing during a continuous enrichment culture from a hydrothermal chimney sample was investigated by molecular methods. The culture was performed in a gas-lift bioreactor under anaerobic conditions, at 90 degrees C and pH 6.5, on a complex medium containing sulfur as the terminal electron acceptor. Archaeal and bacterial diversity was studied. Microorganisms affiliated with the genera Pyrococcus, Marinitoga, and Bacillus were detected through DGGE analysis of 16S rDNA. Additional sequences phylogenetically related to Thermococus and epsilon-Proteobacteria were detected by cloning and sequencing of 16S rDNA from two samples of the enrichment culture. In comparison, the sequences retrieved from cloning analysis from an enrichment culture... |
| Tipo: Text |
Palavras-chave: Sequence alignment; Anaerobic digester; Thermotogales; Thermophile; Deep sea vent. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-364.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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| Lakhal, Raja; Pradel, Nathalie; Postec, Anne; Ivier, Bernard; Cayol, Jean-luc; Godfroy, Anne; Fardeau, Marie-laure; Gales, Gregoire. |
| A novel, anaerobic, chemo-organotrophic bacterium, designated strain Ra1766HT, was isolated from sediments of the Guaymas basin (Gulf of California, Mexico) taken from a depth of 2002 m. Cells were thin, motile, Gram-stain-positive, flexible rods forming terminal endospores. Strain Ra1766H(T) grew at temperatures of 25-45 degrees C (optimum 30 degrees C), pH 6.7-8.1 (optimum 7.5) and in a salinity of 5-60 g l(-1) NaCl (optimum 30 g l(-1)). It was an obligate heterotrophic bacterium fermenting carbohydrates (glucose and mannose) and organic acids (pyruvate and succinate). Casamino acids and amino acids (glutamate, aspartate and glycine) were also fermented. The main end products from glucose fermentation were acetate, butyrate, ethanol, H-2 and CO2.... |
| Tipo: Text |
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| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00296/40742/39992.pdf |
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| Landreau, M.; Duthoit, Frederique; Roussel, Erwan; Schonherr, S.; Georges, Myriam; Godfroy, Anne; Le Blay, G.. |
| Cultivation in a bioreactor of immobilized deep-sea hydrothermal microbial community was tested in order to assess the stability and reactivity of this new system. A community composed of 8 hydrothermal strains was entrapped in a polymer matrix that was used to inoculate a continuous culture in a gas-lift bioreactor. The continuous culture was performed for 41 days at successively 60°C, 55°C, 60°C, 85°C and 60°C, at pH 6.5, in anaerobic condition and constant dilution rate. Oxic stress and pH variations were tested at the beginning of the incubation. Despite these detrimental conditions, 3 strains including 2 strict anaerobes were maintained in the bioreactor. High cell concentrations (3 × 108 cells mL−1) and high ATP contents were measured in both liquid... |
| Tipo: Text |
Palavras-chave: Immobilization; Anaerobiosis; Marine (hyper)thermophiles; Continuous culture. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00347/45851/45516.pdf |
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| Alain, Karine; Rolland, Sophie; Crassous, Philippe; Lesongeur, Francoise; Zbinden, Magali; Le Gall, Christian; Godfroy, Anne; Page, Antoine; Juniper, S Kim; Cambon-bonavita, Marie-anne; Duchiron, Francis; Querellou, Joel. |
| A novel thermophilic, chemolithoautotrophic T bacterium, designated as NE1206(T), was isolated from a Juan de Fuca Ridge hydrothermal vent sample (tubes of the annelid polychaete Paralvinella sulfincola attached to small pieces of hydrothermal chimney). The cells were rod-shaped (1.2-3.5x0.4-0.7 mum), occurring as single motile rods or forming macroscopic aggregates visible as pinkish to brownish streamers. The new isolate was anaerobic. It grew between 50 and 70 degreesC (optimum 60-65 degreesC doubling time approximately 1 h 15 min at 60 degreesC), between pH 5.0 and 7.5 (optimum pH around 6.0-6.5) and at sea salts concentrations between 20 and 40 g l(-1) (optimum 30 g l(-1)). Cells grew chemolithoautotrophically in an H-2/CO2 atmosphere (80/20, v/v; 200... |
| Tipo: Text |
Palavras-chave: Thermophile; Nitrate reducing; Lithotroph; Desulfurobacterium crinifex; Deep sea hydrothermal vent; Cell networks. |
| Ano: 2003 |
URL: https://archimer.ifremer.fr/doc/2003/publication-663.pdf |
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| Mercier, Coraline; Lossouarn, Julien; Haverkamp, Thomas; Bienvenu, Nadège; Godfroy, Anne; Cueff-gauchard, Valerie; Geslin, Claire; Nesbo, Camilla. |
| Here, we present the draft genome sequences of two thermophilic Marinitoga strain members of the Thermotogales order, Marinitoga camini DV1155 and Marinitoga camini DV1197. These strains were isolated from deep-sea hydrothermal vents of the Mid-Atlantic Ridge. |
| Tipo: Text |
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| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00357/46833/46708.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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| Byrne, Nathalie; Lesongeur, Francoise; Bienvenu, Nadege; Geslin, Claire; Alain, Karine; Prieur, Daniel; Godfroy, Anne. |
| Both cultivation and molecular techniques were used to investigate the microbial diversity and dynamic of a deep-sea vent chimney. The enrichment cultures performed in a gas-lift bioreactor were inoculated with a black smoker chimney sample collected on TAG site on the mid-Atlantic ridge. To mimic as close as possible environmental conditions, the cultures were performed in oligotrophic medium with nitrogen, hydrogen and carbon dioxide (N-2/H-2/CO2) gas sweeping. Also, the temperature was first settled at a temperature of 85A degrees C and colloidal sulphur was added. Then, the temperature was lowered to 60A degrees C and sulphur was omitted. Archaeal and bacterial diversity was studied in both culture and natural samples. Through 16S rRNA gene sequences... |
| Tipo: Text |
Palavras-chave: 16S rRNA genes; Oligotrophic condition; Environmental condition; Bioreactor; Continuous enrichment culture; Microbial diversity; Deep sea hydrothermal vent. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6920.pdf |
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| Landreau, M.; Duthoit, Frederique; Claeys-bruno, M.; Vandenabeele-trambouze, O.; Aubry, T.; Godfroy, Anne; Le Blay, Gwenaelle. |
| Aims The aims of this study were (i) to develop a protocol for the entrapment of anaerobic (hyper)thermophilic marine micro-organisms; (ii) to test the use of the chosen polymers in a range of physical and chemical conditions and (iii) to validate the method with batch cultures. Methods and Results The best conditions for immobilization were obtained at 80°C with gellan and xanthan gums. After 5-week incubation, beads showed a good resistance to all tested conditions except those simultaneously including high temperature (100°C), low NaCl (<0∙5 mol l−1) and extreme pH (4/8). To confirm the method efficiency, batch cultures with immobilized Thermosipho sp. strain AT1272 and Thermococcus kodakarensis strain KOD1 showed an absence of detrimental effect... |
| Tipo: Text |
Palavras-chave: (hyper)thermophilic marine micro-organisms; Anaerobiosis; Entrapment; Gellan; Immobilization; Xanthan. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00332/44352/44000.pdf |
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| Vigneron, Adrien; L Haridon, Stephane; Godfroy, Anne; Roussel, Erwan; Cragg, Barry A.; Parkes, R. John; Toffin, Laurent. |
| In the Sonora Margin cold seep ecosystems (Gulf of California), sediments underlying microbial mats harbor high biogenic methane concentrations, fueling various microbial communities, such as abundant lineages of anaerobic methanotrophs (ANME). However, the biodiversity, distribution, and metabolism of the microorganisms producing this methane remain poorly understood. In this study, measurements of methanogenesis using radiolabeled dimethylamine, bicarbonate, and acetate showed that biogenic methane production in these sediments was mainly dominated by methylotrophic methanogenesis, while the proportion of autotrophic methanogenesis increased with depth. Congruently, methane production and methanogenic Archaea were detected in culture enrichments amended... |
| Tipo: Text |
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| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00256/36737/35338.pdf |
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| Registros recuperados: 42 | |
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