HR: 1340h
AN: OS43A-0995    [Abstracts]
TI: Microbial Diversity in Samples of High Temperature Vent Chimneys From the 71 °N Hydrothermal Fields at the Arctic Mid-Ocean Ridge
AU: * Steinsbu, B O
EM: bjorn.steinsbu@geo.uib.no
AF: Centre for Geobiology, University of Bergen, Allegaten 41, Bergen, N-5007, Norway
AU: * Steinsbu, B O
EM: bjorn.steinsbu@geo.uib.no
AF: Department of Earth Science, University of Bergen, Allegaten 41, Bergen, N-5007, Norway
AU: Daae, F
EM: frida.daae@bio.uib.no
AF: Centre for Geobiology, University of Bergen, Allegaten 41, Bergen, N-5007, Norway
AU: Daae, F
EM: frida.daae@bio.uib.no
AF: Department of Biology, University of Bergen, Jahnebakken 5, Bergen, N-5007, Norway
AU: Ovreaas, L
EM: lise.ovreas@bio.uib.no
AF: Centre for Geobiology, University of Bergen, Allegaten 41, Bergen, N-5007, Norway
AU: Ovreaas, L
EM: lise.ovreas@bio.uib.no
AF: Department of Biology, University of Bergen, Jahnebakken 5, Bergen, N-5007, Norway
AU: Thorseth, I H
EM: ingunn.thorseth@geo.uib.no
AF: Centre for Geobiology, University of Bergen, Allegaten 41, Bergen, N-5007, Norway
AU: Thorseth, I H
EM: ingunn.thorseth@geo.uib.no
AF: Department of Earth Science, University of Bergen, Allegaten 41, Bergen, N-5007, Norway
AU: Pedersen, R B
EM: rolf.pedersen@geo.uib.no
AF: Centre for Geobiology, University of Bergen, Allegaten 41, Bergen, N-5007, Norway
AU: Pedersen, R B
EM: rolf.pedersen@geo.uib.no
AF: Department of Earth Science, University of Bergen, Allegaten 41, Bergen, N-5007, Norway
AB: To get a first insight into the diversity of microorganisms present in the recently discovered active hydrothermal fields along the Mohns Ridge in the Norwegian-Greenland Sea, 16S rDNA clone libraries were constructed with DNA extracted from the walls of active smoker pipes from different locations. Enrichments targeting different physiological groups of microorganisms were prepared both under aerobic, micro-aerobic, and strictly anaerobic conditions. Different combinations of substrates and electron acceptors, pH, and temperatures were used. The enrichment cultures were monitored by use of PCR in combination with denaturing gradient gel electrophoresis (PCR-DGGE) and partial 16S rDNA sequencing. Species dominating in the enrichments were isolated, and their 16S rRNA genes were analyzed. The clones obtained from DNA amplified with primers specific for Archaea represented members of the orders Archaeoglobales, Thermococcales, Desulfurococcales, and Thermoproteales, as well as some unidentified groups. Three major fractions of the clones showed highest similarity to hyperthermophiles belonging to the families Pyrodictiaceae and Desulfurococcaceae, and an unidentified group which was given the name "Arctic Ridge Hydrothermal Vent Archaea" (ARHVA). The major fraction of the clones obtained by use of PCR primers specific for Bacteria affiliated with various genera of Aquificales. Clones representing Proteobacteria, Deferribacteres, Bacteroidetes, Deinococcus- Thermus, Chloroflexi and Firmicutes were also detected. Many clones were relatively distantly related to sequences in the GenBank database. Different types of both thermophiles and hyperthermophiles were enriched and isolated. The isolates were phylogenetically affiliated to Thermotogales, Thermales, Nautilales, Aquificales, Archaeoglobales, Thermococcales, and Desulfurococcales. The cultivation experiments documented the presence of microorganisms mediating various metabolic processes including fermentation, reduction of sulfate, ferric iron, nitrate, oxygen and elemental sulfur. The information gained from the clone libraries and enrichment cultures revealed that already well-characterized phylogenetic groups, as well as clusters unique for these hydrothermal fields, were present.
DE: 0400 BIOGEOSCIENCES
DE: 0410 Biodiversity
DE: 0448 Geomicrobiology
SC: Ocean Sciences [OS]
MN: 2007 Fall Meeting