Hydrogenases catalyze the activation or production of molecular hydrogen. Due to their potential importance for future biotechnological applications, these enzymes have been in the focus of intense research for the past decades. Bidirectional [NiFe] hydrogenases are of particular interest as they couple the reversible cleavage of hydrogen to the redox conversion of NAD(H). In this account, we review the current state of knowledge about mechanistic aspects and structural determinants of these complex multi-cofactor enzymes. Special emphasis is laid on the oxygen-tolerant NAD(H)-linked bidirectional [NiFe] hydrogenase from Ralstonia eutropha.
- NADH regeneration
- Oxygen tolerance