Abstract
Hydrogenases play crucial roles in the hydrogen metabolism by catalyzing the production and decomposition of H2. The membrane-bound [NiFe]-hydrogenase is a representative member of O2-tolerant hydrogenases, but the mechanism of which is poorly understood. Recently, we and other groups have reported the crystal structures of membrane-bound [NiFe]-hydrogenases, which revealed an unprecedented structure of one of three iron-sulfur clusters in the enzyme. Together with the spectroscopic study that shows the unique iron-sulfur cluster takes three oxidation states under physiological redox potentials, we concluded that the iron-sulfur cluster plays a key role in the O2-tolerant mechanism of the membrane-bound [NiFe]-hydrogenase.
