Structural and Functional Analogues of the Active Sites of the [Fe]-, [NiFe]-, and [FeFe]-Hydrogenases

Reviews of chemistry relating to the synthesis of structural and functional analogues of the three classes of hydrogenases were reported. Shima and co-workers showed the reconstitution of an [Fe]-hydrogenase apoenzyme from Methanothermobacter jannaschii with an iron cofactorfom methanothermobacter marburgensis, which allowed the crystallization of an active enzyme and its characterization by X-ray crystallography. It was observed that in the bimetallic hydrogenases, the electrons from the oxidation of dihydrogen flow from the active site through a set of iron-sulfur cluster to an electron acceptor protein partner. Several groups also reviewed the structure, function, and mechanistic aspects of [NiFe]-hydrogenases together with advances in computational modeling of this enzyme. The x-ray crystallography showed that active site of the [NiFe]-hydrogenase was comprised of a nickel and an iron connected by bridging thiolates.