An efficient light-driven P450 BM3 biocatalyst.

P450s are heme thiolate enzymes that catalyze the regio- and stereoselective functionalization of unactivated C-H bonds using molecular dioxygen and two electrons delivered by the reductase. We have developed hybrid P450 BM3 heme domains containing a covalently attached Ru(II) photosensitizer in order to circumvent the dependency on the reductase and perform P450 reactions upon visible light irradiation. A highly active hybrid enzyme with improved stability and a modified Ru(II) photosensitizer is able to catalyze the light-driven hydroxylation of lauric acid with total turnover numbers of 935 and initial reaction rate of 125 mol product/(mol enzyme/min).