Hydrogenases: Hydrogen-Activating Enzymes

Hydrogen is an important metabolite for many microrganisms. H2 is either produced or consumed by hydrogenase enzymes, according to the reaction: H2⇌2 H+ + 2 e−. The catalytic sites of the two major families of hydrogenases include a dinuclear center, either NiFe (see picture) or FeFe, along with proteic and nonproteic ligands. The structure and activity of these sites are currently being studied, with the aim of designing cheap biological or chemical catalysts able to produce hydrogen, the ideal clean fuel.