Hydrogenotrophs are organisms that are able to metabolize molecular hydrogen as a source of energy. An example of hydrogenotrophy is performed by carbon dioxide reducing organisms. They utilize CO2 and H2 to produce methane, CH4, by the following reaction:
CO2 + 4H2 → CH4 + 2H2OOther hydrogenotrophic metabolic pathways include acetogenesis, sulfate reduction, and other Hydrogen oxidizing bacteria.
References
Hydrogenotroph Wikipedia(Text) CC BY-SA