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| Registros recuperados: 42 | |
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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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| 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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| 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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| 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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| 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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| Ciobanu, Maria Cristina; Burgaud, Gaetan; Dufresne, Alexis; Breuker, Anja; Redou, Vanessa; Ben Maamar, Sarah; Gaboyer, Frederic; Vandenabeele-trambouze, Odile; Lipp, Julius Sebastian; Schippers, Axel; Vandenkoornhuyse, Philippe; Barbier, Georges; Jebbar, Mohamed; Godfroy, Anne; Alain, Karine. |
| The subsurface realm is colonized by microbial communities to depths of >1000 meters below the seafloor (m.b.sf.), but little is known about overall diversity and microbial distribution patterns at the most profound depths. Here we show that not only Bacteria and Archaea but also Eukarya occur at record depths in the subseafloor of the Canterbury Basin. Shifts in microbial community composition along a core of nearly 2 km reflect vertical taxa zonation influenced by sediment depth. Representatives of some microbial taxa were also cultivated using methods mimicking in situ conditions. These results suggest that diverse microorganisms persist down to 1922 m.b.sf. in the seafloor of the Canterbury Basin and extend the previously known depth limits of... |
| Tipo: Text |
Palavras-chave: Deep biosphere; Subsurface life; Eukaryote; Record depth. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00201/31243/29895.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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| 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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| Cruaud, Perrine; Vigneron, Adrien; Lucchetti-miganeh, Celine; Ciron, Pierre Emmanuel; Godfroy, Anne; Cambon-bonavita, Marie-anne. |
| Next-generation sequencing (NGS) opens up exciting possibilities for improving our knowledge of environmental microbial diversity, allowing rapid and cost-effective identification of both cultivated and uncultivated microorganisms. However, library preparation, sequencing, and analysis of the results can provide inaccurate representations of the studied community compositions. Therefore, all these steps need to be taken into account carefully. Here we evaluated the effects of DNA extraction methods, targeted 16S rRNA hypervariable regions, and sample origins on the diverse microbes detected by 454 pyrosequencing in marine cold seep and hydrothermal vent sediments. To assign the reads with enough taxonomic precision, we built a database with about 2,500... |
| Tipo: Text |
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| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00204/31495/29907.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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| 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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| 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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| 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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| Henri, Pauline A.; Rommevaux-jestin, Celine; Lesongeur, Francoise; Mumford, Adam; Emerson, David; Godfroy, Anne; Menez, Benedicte. |
| To explore the capability of basaltic glass to support the growth of chemosynthetic microorganisms, complementary in situ and in vitro colonization experiments were performed. Microbial colonizers containing synthetic tholeitic basaltic glasses, either enriched in reduced or oxidized iron, were deployed off-axis from the Mid Atlantic Ridge on surface sediments of the abyssal plain (35°N; 29°W). In situ microbial colonization was assessed by sequencing of the 16S rRNA gene and basaltic glass alteration was characterized using Scanning Electron Microscopy, micro-X-ray Absorption Near Edge Structure at the Fe-K-edge and Raman microspectroscopy. The colonized surface of the reduced basaltic glass was covered by a rind of alteration made of iron-oxides trapped... |
| Tipo: Text |
Palavras-chave: Basaltic glass; Zetaproteobacteria; Bio-mediated alteration; Iron-oxidation; Abyssal plain. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00378/48894/49332.pdf |
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| Killelea, Tom; Palud, Adeline; Akcha, Farida; Lemor, Mélanie; L'Haridon, Stephane; Godfroy, Anne; Henneke, Ghislaine. |
| 8-oxodeoxyguanosine (8-oxodG), a major oxidised base modification, has been investigated to study its impact on DNA replication in hyperthermophilic Archaea. Here we show that 8-oxodG is formed in the genome of growing cells, with elevated levels following exposure to oxidative stress. Functional characterisation of cell-free extracts and the DNA polymerisation enzymes, PolB, PolD, and the p41/p46 complex, alone or in the presence of accessory factors (PCNA and RPA) indicates that translesion synthesis occurs under replicative conditions. One of the major polymerisation effects was stalling, but each of the individual proteins could insert and extend past 8-oxodG with differing efficiencies. The introduction of RPA and PCNA influenced PolB and PolD in... |
| Tipo: Text |
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| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00502/61372/64989.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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| 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; 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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| Registros recuperados: 42 | |
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