Objetivo
Samples collected from active deep-sea hydrothermal fields of East Pacific Ridge (13° N, 2,600 m depth) in May-June 1999 during the AMISTAD cruise will be studied in the course of this project in order to study the metabolic and phylogenetic diversity of thermophilic lithotrophic microorganisms. Using biogeochemical, microbiological, molecular, and biochemical methods will fulfill the investigation. Data of radioisotopic experiments made in situ would allow measuring the rates of most important lithoautotrophic processes (methanogenesis, actogenesis, sulfate reduction) occurring in this environment. Simultaneously, the microbiological approach will result in the enumeration and isolation of representatives of diverse physiological groups of lithotrophic thermophilic prokaryotes: methanogens, sulfate- and sulfur-reducers, nitrate reducers, iron- and manganese reducers, anaerobic CO-oxidizers. Complete characterization of the new isolates will be performed. Analyses of DNA by microchip method will reveal the identity of the dominant phylogenetic groups of thermophilic prokaryotes.
Samples of DNA extracted from chimneys will be used to obtain 16S rDNA clone libraries to analyse in detail the 16S rRNA genes contained in the community. To understand the role of these microorganisms, their key metabolic enzymes will be studied. The successful application of these combined approaches should allow the reconstruction of the structure of a complex and evolutionary significant microbial community of lithotrophic microorganisms, inhabiting deep-sea hot vents and provide new clues on the origin of the present populations.
Tema(s)
Convocatoria de propuestas
Data not availableRégimen de financiación
Data not availableCoordinador
29280 Plouzan?
Francia