title: Diversity and function in microbial mats from the Lucky Strike hydrothermal vent field.
abstract: Diversity and function in microbial mats from the Lucky Strike hydrothermal vent field (Mid-Atlantic Ridge) were investigated using molecular approaches. DNA and RNA were extracted from mat samples overlaying hydrothermal deposits and Bathymodiolus azoricus mussel assemblages. We constructed and analyzed libraries of 16S rRNA gene sequences and sequences of functional genes involved in autotrophic carbon fixation [forms I and II RuBisCO (cbbL/M), ATP-citrate lyase B (aclB)]; methane oxidation [particulate methane monooxygenase (pmoA)] and sulfur oxidation [adenosine-5'-phosphosulfate reductase (aprA) and soxB]. To gain new insights into the relationships between mats and mussels, we also used new domain-specific 16S rRNA gene primers targeting Bathymodiolus sp. symbionts. All identified archaeal sequences were affiliated with a single group: the marine group 1 Thaumarchaeota. In contrast, analyses of bacterial sequences revealed much higher diversity, although two phyla Proteobacteria and Bacteroidetes were largely dominant. The 16S rRNA gene sequence library revealed that species affiliated to Beggiatoa Gammaproteobacteria were the dominant active population. Analyses of DNA and RNA functional gene libraries revealed a diverse and active chemolithoautotrophic population. Most of these sequences were affiliated with Gammaproteobacteria, including hydrothermal fauna symbionts, Thiotrichales and Methylococcales. PCR and reverse transcription-PCR using 16S rRNA gene primers targeted to Bathymodiolus sp. symbionts revealed sequences affiliated with both methanotrophic and thiotrophic endosymbionts.
authors.affiliation: IFREMER, DEEP/Laboratoire de Microbiologie des Environnements Extrêmes UMR6197, Technopôle Brest Iroise, BP70, Plouzané, France. valentin.crepeau@ifremer.fr
authors.forename: Valentin
authors.initials: V
authors.lastname: Crépeau
authors.forename: Marie-Anne
authors.initials: MA
authors.lastname: Cambon Bonavita
authors.forename: Françoise
authors.initials: F
authors.lastname: Lesongeur
authors.forename: Henintsoa
authors.initials: H
authors.lastname: Randrianalivelo
authors.forename: Pierre-Marie
authors.initials: PM
authors.lastname: Sarradin
authors.forename: Jozée
authors.initials: J
authors.lastname: Sarrazin
authors.forename: Anne
authors.initials: A
authors.lastname: Godfroy
mesh_terms: D000818:Animals; D001105:Archaea / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D001419:Bacteria / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D044822:Biodiversity; D002244:Carbon / Q000378:metabolism; D019641:DNA, Archaeal / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D015723:Gene Library; D008697:Methane / Q000378:metabolism; D059013:Microbial Consortia; D049879:Mytilidae / Q000382:microbiology; D010084:Oxidation-Reduction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology*; D013455:Sulfur / Q000378:metabolism; D013559:Symbiosis
chemical_list: D019641:DNA, Archaeal; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D013455:Sulfur; D002244:Carbon; D008697:Methane