HR: 1340h
AN: B33A-0847    [Abstracts]
TI: Bacterial Diversity and Spatial Variability Found in a Mn-Fe Oxide Encrusted Microbial Mat From the 5000 Meter-Deep Hydrothermal Vent 'Ula Nui, Hawaii
AU: * Davis, R E
EM: davisr@ebs.ogi.edu
AF: OHSU School of Science and Engineering, 20000 NW Walker Rd, Beaverton, OR 97006, United States
AU: Moyer, C L
EM: cmoyer@hydro.biol.wwu.edu
AF: Western Washington University, 516 High Street, Bellingham, WA 98205, United States
AU: Curtis, A C
EM: acurtis@cc.wwu.edu
AF: Western Washington University, 516 High Street, Bellingham, WA 98205, United States
AU: Staudigel, H
EM: hstaudigel@ucsd.edu
AF: Scripps Institute of Oceanography, 8602 La Jolla Shores Drive, La Jolla, CA 92037, United States
AU: Tebo, B M
EM: tebo@ebs.ogi.edu
AF: OHSU School of Science and Engineering, 20000 NW Walker Rd, Beaverton, OR 97006, United States
AB: 'Ula Nui Vent Field was discovered on the southern flank of Loihi Seamount during the 2006 FeMO Microbial Observatory expedition at over 5000 meters depth. The vent field exhibited abundant low temperature (<2°C above ambient) seeps which were covered with extensive mineral-encrusted microbial mat material. The microbial mats consisted of a 0.5-3 cm thick upper mat which was comprised of laminated layers of manganese oxides and iron oxides which overlayed a flocculent iron oxide mat that could attain depths of over 1 m deep. Bacterial communities from the top and bottom mats were analyzed using SSU rRNA terminal-restriction fragment polymorphisms (T-RFLP) coupled with traditional clone library analysis. T-RFLP chromatograms indicate dominance of the ζ- Proteobacteria in both the top and lower mat. Cluster analysis of the T- RFLP fingerprints show a strong correlation between the bottom mat and iron oxide-encrusted microbial mats found in the hydrothermally active Pele's Pit near the summit of Loihi Seamount. The top mat clusters with iron and manganese oxide encrusted microbial mats found at various sites on Loihi Seamount not associated with measurable active hydrothermal venting. Clone library analysis show that the top mat was dominated by phylotypes related to the δ- γ- and the recently described ζ- Proteobacteria, along with members of the Planctomycete Division. The dominance of ζ- Proteobacteria and Planctomycete phylotypes implies that neutrophilic iron oxidation and anaerobic ammonia oxidation are active metabolisms in the top mat bacterial community. Anaerobic ammonia oxidation coupled with nitrite reduction may also be an integral metabolism in this community since some Planctomycete phylotypes from the top mat cluster within the anammox clade.
DE: 0410 Biodiversity
DE: 0419 Biomineralization
DE: 0448 Geomicrobiology
DE: 0465 Microbiology: ecology, physiology and genomics (4840)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting