Efficient photoinduced electron transfer from inorganic semiconductor TiO2to bacterial hydrogenase

Hydrogenase fromThiocapsa roseopersicinaadsorbed on TiO2particles, using electrons photogenerated in the conduction band of the semiconductor, in the presence of an organic electron donor, carries out hydrogen production with the rate comparable to that obtained with reduced methyl viologen as the substrate. Under conditions of the efficient hydrogenase adsorption on TiO2(1.6 mM CaCl2, 0.05 M Tris buffer, pH 7.2) the quantum efficiency of hydrogen photoproduction is up to 10%. Coupling of inorganic semiconductors with bacterial hydrogenase may be regarded as a way to the development of artificial photocatalytic systems of light energy conversion.