Function of Biohydrogen Metabolism and Related Microbial Communities in Environmental Bioremediation

Hydrogen (H-2) metabolism has attracted considerable interest because the activities of H-2-producing and consuming microbes shape the global H-2 cycle and may have vital relationships with the global cycling of other elements. There are many pathways of microbial H-2 emission and consumption which may affect the structure and function of microbial communities. A wide range of microbial groups employ H-2 as an electron donor to catalyze the reduction of pollutants such as organohalides, azo compounds, and trace metals. Syntrophy coupled mutualistic interaction between H-2-producing and H-2-consuming microorganisms can transfer H-2 and be accompanied by the removal of toxic compounds. Moreover, hydrogenases have been gradually recognized to have a key role in the progress of pollutant degradation. This paper reviews recent advances in elucidating role of H-2 metabolism involved in syntrophy and hydrogenases in environmental bioremediation. Further investigations should focus on the application of bioenergy in bioremediation to make microbiological H-2 metabolism a promising remediation strategy.