Olkiluoto Island deep subsurface Metagenome. Olkiluoto Island deep subsurface

At specific depths in the crystalline bedrock of Olkiluoto Island, Finland, archaea dominate the microbial communities. At approximately 100 m depth close to the repository for low and intermediate radioactive waste up tp 50 percent of the microbial community consist of archaeal lineages, of which the Deep Sea Hydrothermal Vent Euryarchaeota --DHVE-- are the most common. At 300 m depth, close to the depth of the repository for spent nuclear fuel up to 90 percent of the microbial community has been shown to consist of archaea, of which the most common group is the ANME-2D archaea, aka Candidatus Methanoperedens nitroreducens. Very little is still known about both of these archaeal groups, although they are commonly found in deep subsurface environments. ANME-2D archaea have been shown to oxidize methane by reducing nitrate. While methane is abundant in the deep groundwater of Olkiluoto, nitrate is scarce. Sulfur compounds, however are abundant and sulfur oxidation and sulfate reduction are common processes. With this sequencing proposal we aim to obtain more information of about these specific archaeal groups, about their metabolic characteristics and metabolic pathways and to compare them with similar studies from other locations. PI Malin Bomberg VTT Technical Research Centre of Finland