Consulta: subjectFacets:"Sources hydrothermales"
Registros recuperados: 5
Data/hora: 16/06/2024 06:44:33

Influence des communautés microbiennes sédimentaires sur la répartition faunistique dans les sites hydrothermaux et les zones d'émissions de fluides froids du bassin de Guaymas par Perrine Cruaud
Provedor de dados: 5
Autores: Cruaud, Perrine.
Au niveau des fonds océaniques, souvent considérés comme des déserts aux conditions de vie extrêmes, des oasis luxuriants de vie existent pourtant. Les sources hydrothermales et les suintements froids, principalement localisés au niveau des dorsales océaniques et des marges continentales, vont permettre le développement de communautés microbiennes et animales très particulières. Le Bassin de Guaymas, situé dans le Golfe de Californie (Mexique) présente la particularité de regrouper à la fois une zone de sources hydrothermales et une zone de suintements froids, situées à une soixantaine de kilomètres l’une de l’autre, et toutes deux recouvertes par une épaisse couche sédimentaire. Ces deux zones sont également colonisées par des étendues de bivalves, des...
Tipo: Text
Palavras-chave: Bassin de Guaymas; Suintements froids; Sources hydrothermales; Communautés microbiennes sédimentaires; Colonisateurs de surface; Pyroséquençage; Q-PCR; FISH.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00407/51843/52452.pdf

Etude de la diversité métabolique des micro-organismes des sources hydrothermales
Provedor de dados: 5
Autores: Byrne, Nathalie.
Since the discovery of oceanic hydrothermal vents, microbial diversity of this extreme environment was studied using both cultivation and molecular approaches. In this study the microbial diversity of active chimney from both TAG and Lucky Strike sites (Mid Atlantic Ridge) was investigated using both molecular survey and continuous enrichment culture in a bioreactor. To reproduce as close as possible environmental conditions the cultures were performed in oligotrophic conditions, in the presence of hydrogen and carbondioxide in the gas sweeping mix or using in situ sampled fluid/sea water mix as culture medium. The effect of environmental changes such as temperature and the absence or presence of sulphur was also investigated. Archaeal and Bacterial...
Tipo: Text
Palavras-chave: Culture; Molecular diversity; Metabolism; Hydrothermal vents; Microorganisms; Microbiology; Culture; Diversité moléculaire; Métabolisme; Sources hydrothermales; Micro organismes; Microbiologie.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/these-7295.pdf

Dynamique spatiale et temporelle des communautés microbiennes dans les édifices hydrothermaux actifs
Provedor de dados: 5
Autores: Francois, David.
In deep-sea hydrothermal vents, the mixing between hot, acidic and anoxic hydrothermal fluid with seawater leads to the formation of hydrothermal chimneys. These are porous structures whose mineralogical composition changes over time. Thermal and chemical gradients are favourable to the growth of microbial communities, that present a high taxonomic, physiologic and metabolic diversity. Despite numerous studies about the microbiology of hydrothermal environments, the spatial and temporal dynamics of microbial communities in hydrothermal vents remain relatively unknown. Our study was based on a rigorous sampling of hydrothermal chimneys from six sites in the Lucky Strike hydrothermal vent field, and the associated proximal plume. The mineralogical...
Tipo: Text
Palavras-chave: Sources hydrothermales; Communautés microbiennes; Persephonella; Hydrothermal vents; Microbial communities; Persephonella.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00690/80209/83298.pdf

Exopolysaccharides produced by bacteria isolated from deep-sea hydrothermal vents: new agents with therapeutic potential
Provedor de dados: 5
Autores: Colliec-jouault, Sylvia; Zanchetta, P; Helley, D; Ratiskol, Jacqueline; Sinquin, Corinne; Fischer, A. M.; Guezennec, Jean.
Bacterial polysaccharides offer fascinating potential applications for the pharmaceutical industry. Although many known marine bacteria produce exopolysaccharides (EPS), continuation in looking for new polysaccharide-producing micro-organisms is promising. Marine bacteria, isolated from deep-sea hydrothermal vents, have demonstrated their ability to produce in aerobic conditions, unusual EPS. With the aim of discovering biological activities, EPS presenting different structural features were studied. An EPS secreted by Vibrio, diabolicus was evaluated on the restoration of bone integrity in experimental model and was demonstrated to be a strong bone-healing material. Another EPS produced by Alteromonas infernus was modified in order to obtain new...
Tipo: Text
Palavras-chave: Hydrothermal vents; Exopolysaccharides; Bone healing; Biomimetic; Anticoagulant activity; Sources hydrothermales; Exopolysaccharide; Cicatrisation osseuse; Biomimétique; Activité anticoagulante.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/publication-2117.pdf

Etude d'oligosaccharides bioactifs issus d'exopolysaccharides bactériens : obtention, caractérisation et relation structure/fonction
Provedor de dados: 5
Autores: Roger, Olivier.
Unusual exopolysaccharides (EPS) produced by heterotrophic aerobic and mesophilic bacteria originating from hydrothermal vent, were reviewed as a new source of polysaccharidic structures endowed with innovative biological properties. The first step of this study was the structure determination of the EPS GY785, synthesized by Alteromonas infernus. A highly branched nonasaccharidic repetitive unit was identified using chemical modifications and nuclear magnetic resonance spectroscopy. This 106 g/mol polysaccharide is composed of glucose, galactose, glucuronic acid, galacturonic acid, and contains a single branched ramification and one sulphate group.  The second step was the preparation of low molecular weight bioactive polysaccharides presenting interest...
Tipo: Text
Palavras-chave: Phosphorylation; Sulphation; Depolymerization; NMR spectroscopy; Structure; Deep sea hydrothermal vent; Bacteria; Exopolysaccharides; Activité anticoagulante; Phosphatation; Sulfatation; Dépolymérisation; Spectroscopie de RMN; Structure; Sources hydrothermales; Bactéries; Exopolysaccharides.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/these-622.pdf