The Intermolecular Wires How Electrons Enter and Exit Hydrogenase

The Intermolecular Wires How Electrons Enter and Exit Hydrogenase 

Several terminal electron acceptors are coupled to H2 oxidation. These include O2, nitrate, sulfate, carbon dioxide, fumarate, and halogenated organics. Electron donors that couple to proton reduction include pyruvate and carbon monoxide. The electron donors or acceptors for the D. desulfu-ricans Fe-only hydrogenase is cytochrome c3 or c6 (Guerlesquin et al., 1994 Verhagen et al., 1994). 

In the NiFe hydrogenase, a icrowni of acidic residues surround the solvent-exposed histidine ligand to the distal cluster (Volbeda et al., 1995). It was suggested that this pateh eould serve as a site for recognition by the redox partner, which is a monoheme or polyheme cytochrome. 

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