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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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Godfroy, Anne; Raven, N; Sharp, R. |
The deep-sea vent archaeon Pyrococcus abyssi strain ST549 was grown in batch cultures in closed bottles and by continuous culture in a gas-lift bioreactor, both in the presence and in the absence of elemental sulfur. Growth on carbohydrates, proteinaceous substrates and amino acids was investigated. The disaccharides maltose and cellobiose were shown not to be able to enhance growth suggesting that P. abyssi ST549 is unable to use them as carbon sources. By contrast, proteinaceous substrates such as peptone and brain heart infusion were shown to be very good substrates for the growth of P. abyssi ST549 and allowed growth at high steady-state cell densities in continuous culture. Growth on brain heart infusion was shown to require additional nutrients when... |
Tipo: Text |
Palavras-chave: Sulfur requirement; Continuous culture; Nutrition; Hyperthermophile; Pyrococcus abyssi. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/publication-1087.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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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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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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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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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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Martins, I.; Colaco, A.; Santos, Raphael; Lesongeur, Francoise; Godfroy, Anne; Sarradin, Pierre-marie; Cosson, R. P.. |
The edifice walls of the Eiffel Tower hydrothermal vent site (Mid-Atlantic Ridge, Lucky Strike vent field) are populated with dense communities of dual symbioses harboring vent mussel Bathymodiolus azoricus, some of which are covered by white filamentous mats belonging to sulfur-oxidizing bacteria. Mussels were collected in both the presence and absence of the filamentous bacteria. A sample of the filamentous bacteria was collected and water measurements of temperature, CH4 and H2S were recorded at the collection area. The whole soft tissues were analyzed for total lipid, carbohydrate and total protein. Metallothioneins and metals (Cu, Fe and Zn) levels were determined in the major organs. The results showed no significant physiological and toxicological... |
Tipo: Text |
Palavras-chave: Vent mussel; Metals; Metallothioneins; Filamentous bacteria; Eiffel Tower; Biomarkers. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6821.pdf |
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Byrne, Nathalie; Strous, Marc; Crepeau, Valentin; Kartal, Boran; Birrien, Jean-louis; Schmid, Markus; Lesongeur, Francoise; Schouten, Stefan; Jaeschke, Andrea; Jetten, Mike; Prieur, Daniel; Godfroy, Anne. |
Recent studies indicate that ammonia is an important electron donor for the oxidation of fixed nitrogen, both in the marine water column and sediments. This process, known as anammox, has so far only been observed in a large range of temperature habitats. The present study investigated the role of anammox in hydrothermal settings. During three oceanographic expeditions to the Mid-Atlantic Ridge, hydrothermal samples were collected from five vent sites, at depths ranging from 750 to 3650m from cold to hot habitats. Evidence for the occurrence of anammox in these particular habitats was demonstrated by concurrent surveys, including the amplification of 16S rRNA gene sequences related to known anammox bacteria, ladderanes lipids analysis and measurement of a... |
Tipo: Text |
Palavras-chave: Hydrothermal vent; Ladderanes; 16S rRNA; Activity; Micro organisms; Anammox. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6921.pdf |
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Takai, Ken; Miyazaki, Masayuki; Hirayama, Hisako; Nakagawa, Satoshi; Querellou, Joel; Godfroy, Anne. |
P>Two novel, thermophilic piezophiles, capable of chemolithoautotrophic growth, are successfully cultivated and isolated from a black smoker chimney at the TAG field (Mid Atlantic Ridge: MAR) by using a piezophilic cultivation technique. Both strains (strains 106 and 108) represent dominant cultivated populations of the microbial communities in the chimney surface habitat. Strain 106 represents typically thin, long spiral cells under the piezophilic growth condition but short bent cells under the non-piezophilic condition. It is a strictly chemolithoautotrophic gammaproteobacterium using reduced sulfur compounds as the electron donors, and nitrate and O-2 as the electron acceptors. Based on the 16S rRNA gene sequence, strain 106 would represent a novel... |
Tipo: Text |
Palavras-chave: Sp. nov.; Ecological signifiance; Hydrostatic pressure; Subsurface biosphere; Base composition; High temperature; Membrane lipids; Gen. nov.; Microorganisms; Diversity. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6652.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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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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Russ, Lina; Kartal, Boran; Op Den Camp, Huub J. M.; Sollai, Martina; Le Bruchec, Julie; Caprais, Jean-claude; Godfroy, Anne; Damste, Jaap S. Sinninghe; Jetten, Mike S. M.. |
Hydrothermally active sediments are highly productive, chemosynthetic areas which are characterized by the rapid turnover of particulate organic matter under extreme conditions in which ammonia is liberated. These systems might be suitable habitats for anaerobic ammonium oxidizing (anammox) bacteria but this has not been investigated in detail. Here we report the diversity and abundance of anammox bacteria in sediments that seep cold hydrocarbon-rich fluids and hydrothermal vent areas of the Guaymas Basin in the Cortes Sea using the unique functional anammox marker gene, hydrazine synthase (hzsA). All clones retrieved were closely associated to the "Candidatus Scalindua" genus. Phylogenetic analysis revealed two distinct clusters of hzsA sequences (Ca.... |
Tipo: Text |
Palavras-chave: Anammox; HzsA; AprA; Hydrothermal vents; Cold seep; Sulfide. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00180/29156/27555.pdf |
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Callac, Nolwenn; Rommevaux-jestin, Celine; Rouxel, Olivier; Lesongeur, Francoise; Liorzou, Celine; Bollinger, Claire; Ferrant, Anthony; Godfroy, Anne. |
Oceanic basalts host diverse microbial communities with various metabolisms involved in C, N, S, and Fe biogeochemical cycles which may contribute to mineral and glass alteration processes at, and below the seafloor. In order to study the microbial colonization on basaltic glasses and their potential biotic/abiotic weathering products, two colonization modules called AISICS ("Autonomous in situ Instrumented Colonization System") were deployed in hydrothermal deep-sea sediments at the Guaymas Basin for 8 days and 22 days. Each AISICS module contained 18 colonizers (including sterile controls) filled with basaltic glasses of contrasting composition. Chemical analyses of ambient fluids sampled through the colonizers showed a greater contribution of... |
Tipo: Text |
Palavras-chave: Colonization module; Basalt alteration; Guaymas basin; Organic-rich sediment; Hydrothermal systems. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00181/29261/27642.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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Appolaire, Alexandre; Rosenbaum, Eva; Dura, M. Asuncion; Colombo, Matteo; Marty, Vincent; Savoye, Marjolaine Noirclerc; Godfroy, Anne; Schoehn, Guy; Girard, Eric; Gabel, Frank; Franzetti, Bruno. |
Tetrahedral (TET) aminopeptidases are large polypeptide destruction machines present in prokaryotes and eukaryotes. Here, the rules governing their assembly into hollow 12-subunit tetrahedrons are addressed by using TET2 from Pyrococcus horikoshii (PhTET2) as a model. Point mutations allowed the capture of a stable, catalytically active precursor. Small angle x- ray scattering revealed that it is a dimer whose architecture in solution is identical to that determined by x- ray crystallography within the fully assembled TET particle. Small angle x- ray scattering also showed that the reconstituted PhTET2 dodecameric particle displayed the same quaternary structure and thermal stability as the wild-type complex. The PhTET2 assembly intermediates were... |
Tipo: Text |
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Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00177/28820/27491.pdf |
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Lakhal, Raja; Pradel, Nathalie; Postec, Anne; Hamdi, Moktar; Ollivier, Bernard; Godfroy, Anne; Fardeaul, Marie-laure. |
A novel obligately anaerobic, non-spore-forming, rod-shaped mesophilic, halophilic, Gram-stain-negative bacterium, was isolated from sediments of Guaymas Basin. The strain, designated Ra1766G1(T), grew at 20-40 degrees C (optimum, 30-35 degrees C) and at pH 6.0-8.0 (optimum, pH 6.5-7.5). It required 0.5-7.5 % NaCl (optimum, 2-3 %) for growth. Sulfate, thiosulfate, elemental sulfur, sulfite, fumarate, nitrate and nitrite were not used as terminal electron acceptors. Strain Ra1766G1(T) used cellobiose, glucose, mannose, maltose, arabinose, raffinose, galactose, ribose, sucrose, pyruvate and xylose as electron donors. The main fermentation product from glucose metabolism was acetate. The predominant cellular fatty acids were anteiso-C-15:0, iso-C-15:0,... |
Tipo: Text |
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Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00177/28821/27463.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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Registros recuperados: 42 | |
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