Hydrogenase: Properties and applications

Hydrogenase is an enzyme which reversibly activates molecular hydrogen and has potential applications in the production of hydrogen by solar energy. This review describes methods employed for assay of the enzyme, the biological role of hydrogenase in normal cellular metabolism and growth, and the properties of the enzyme. Although hydrogenases isolated from different organisms differ in molecular weight, subunit composition, iron and sulphur content, thermal and oxygen stability, they are all iron-sulphur proteins which cleave hydrogen heterolytically to form a hydride and a proton. The review also describes various systems being developed for the biophotolysis of water to produce hydrogen, and the role of hydrogenase in these systems.