Consulta: subjectFacets:"Microbial mat"
Registros recuperados: 4
Data/hora: 09/06/2024 09:25:42

Mechanistic Morphogenesis of Organo-Sedimentary Structures Growing Under Geochemically Stressed Conditions: Keystone to Proving the Biogenicity of Some Archaean Stromatolites?
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Hickman-lewis, Keyron; Gautret, Pascale; Arbaret, Laurent; Sorieul, Stéphanie; De Wit, Rutger; Foucher, Frédéric; Cavalazzi, Barbara; Westall, Frances.
Morphologically diverse organo-sedimentary structures (including microbial mats and stromatolites) provide a palaeobiological record through more than three billion years of Earth history. Since understanding much of the Archaean fossil record is contingent upon proving the biogenicity of such structures, mechanistic interpretations of well-preserved fossil microbialites can reinforce our understanding of their biogeochemistry and distinguish unambiguous biological characteristics in these structures, which represent some of the earliest records of life. Mechanistic morphogenetic understanding relies upon the analysis of geomicrobiological experiments. Herein, we report morphological-biogeochemical comparisons between micromorphologies observed in growth...
Tipo: Text
Palavras-chave: Microbial mat; Stromatolite; Anoxygenic photosynthesis; X-ray micro-scale computed tomography; Archaean; Early life; Dresser Formation; Middle Marker horizon.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00512/62323/66580.pdf

A novel mcl-PHA produced on coprah oil by Pseudomonas guezennei biovar. tikehau, isolated from a "kopara" mat of French Polynesia
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Simon-colin, Christelle; Raguenes, Gerard; Crassous, Philippe; Moppert, X; Guezennec, Jean.
Pseudomonasguezennei biovar. tikehau was isolated from a microbial mat on the atoll of Tikehau in French Polynesia, and is able to synthesize medium chain length poly-beta-hydroxyalkanaote copolymers when grown on coprah oil. A two-step cultivation process was used and the biosynthesis of PHAs was followed along 52 h by regular culture sampling. The polyester was purified from freeze-dried cells and analysed by nuclear magnetic resonance (NMR), Fourier transform infra red (FTIR), and gas chromatography mass spectrometries. The copolyester produced by P. guezennei biovar. tikehau from coprah oil mainly consisted of saturated monomers, i.e. 3-hydroxyoctanoate (3HO) and 3-hydroxydecanoate (3HD), and the monomeric composition of the polyester did not change...
Tipo: Text
Palavras-chave: Polyhydroxyalkanaote; PHAs; Pseudomonas; "kopara"; Microbial mat.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-6119.pdf

Microbial communities associated with benthic faunal assemblages at cold seep sediments of the Sonora Margin, Guaymas Basin
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: 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

A novel mcl PHA-producing bacterium, Pseudomonas guezennei sp nov, isolated from a 'kopara' mat located in Rangiroa, an atoll of French Polynesia
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Simon-colin, Christelle; Alain, Karine; Colin, Sebastien; Cozien, Joelle; Costa, B; Guezennec, Jean; Raguenes, Gerard.
Aims: The aim of the present study was to describe an aerobic, mesophilic and heterotrophic bacterium, designated RA26, able to produce a medium-chain-length polyhydroxyalkanoate (PHA). It was isolated from a French Polynesian bacterial mat located in the atoll of Rangiroa.   Methods and Results: This micro-organism, on the basis of the phenotypical features and genotypic investigations can be clearly assigned to the Pseudomonas genus and the name of Pseudomonas guezennei is proposed. Optimal growth occurs between 33 and 37 degrees C, at a pH between 6 4 and 7 1 and at ionic strength of 15 g 1(-1) of sea salts. The G+C content of DNA is 63.2%. Under laboratory conditions, this bacterium produced a novel, medium-chain-length PHA, mainly composed of...
Tipo: Text
Palavras-chave: Pseudomonas; Polyhydroxyalkanaote; Microbial mat; Kopara.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-3858.pdf