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Alain, Karine; Callac, Nolwenn; Ciobanu, Maria Cristina; Reynaud, Yann; Duthoit, Frederique; Jebbar, Mohamed. |
Extracting DNA from deep subsurface sediments is challenging given the complexity of sediments types, low bio-masses, resting structures (spores, cysts) frequently encountered in deep sediments, and the potential presence of enzymatic inhibitors. Promising results for cell lysis efficiency were recently obtained by use of a cryogenic mill (Lipp et al., 2008). These findings encouraged us to devise a DNA extraction protocol using this tool. Thirteen procedures involving a combination of grinding in liquid nitrogen (for various durations and beating rates) with different chemical solutions (phenol, chloroform, SDS, sarkosyl, proteinase, GTC), or with use of DNA recovery kits (MagExtractor (R)) were compared. Effective DNA extraction was evaluated in terms of... |
Tipo: Text |
Palavras-chave: Sediment; DNA extraction; Deep subsurface biosphere. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00056/16691/14364.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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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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Alain, Karine; Callac, Nolwenn; Guegan, Marianne; Lesongeur, Francoise; Crassous, Philippe; Cambon-bonavita, Marie-anne; Querellou, Joel; Prieur, Daniel. |
A novel strictly anaerobic, thermophilic, sulfur-reducing bacterium, designated PH1209(T), was isolated from an East Pacific Rise hydrothermal vent (13 degrees N) sample and studied using a polyphasic taxonomic approach. Cells were Gram-negative, motile rods (approx. 1.60x0.40 mu m) with a single polar flagellum. Strain PH1209(T) grew at temperatures between 33 and 65 degrees C (optimum 60 degrees C), from pH 5.0 to 8.0 (optimum 6.0-6.5), and between 2 and 4% (w/v) NaCl (optimum 3%). Cells grew chemolithoautotrophically with H-2 as an energy source, So as an electron acceptor and CO2 as a carbon source. Strain PH1209(T) was also able to use peptone and yeast extract as carbon sources. The G+C content of the genomic DNA was 35 mol%. Phylogenetic: analyses... |
Tipo: Text |
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Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6585.pdf |
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