Deep subsurface microbial communities from Mt. Terri, Switzerland - Autotrophic microbial communities BRH/9 Metagenome

The subsurface biosphere is often cited to harbor vast microbial diversity and to represent a significant contribution to the planet’s biomass. There is little understanding of the metabolic processes fueling these communities and the role of lithoautotrophic growth in nutrient cycling in the subsurface. H2 from geogenic sources such as serpentinization, radiolysis of water or hydrothermal fluid circulation is proposed as a fuel for microbial metabolism in deep subsurface environments where light dependent processes are limited to residual sedimentary carbon. The aim of this project is to identify the metabolic processes supported by H2 and characterize the lithoautotrophic microorganisms in the associated microbial community and to characterize the rate of consumption of H2 in these environments to account for microbial H2 consumption in their repository safety assessment models. To pursue these aims, we have built an underground in situ reactor that is delivering H2 to a borehole in the rock located at the Mt. Terri Underground Rock Laboratory in Switzerland that is instrumented to collect information continuously.We have been monitoring sulfate, sulfide, Fe(II), H2, CH4, organic acids, major cations and anions, alkalinity, borehole pressure as well as collecting samples for metagenomic analysis and for isotopic characterization (S, H and C). JGI Project ID:1029481