Semisynthetic Flavocytochromes Based on Cytochrome P450 2B4: Reductase and Oxygenase Activities

A synthetic flavocytochrome with the reductase and oxygenase activities was obtained by covalent binding of riboflavin to cytochrome P450 2B4. The reactions catalyzed by the newly synthesized flavocytochromes were studied. Formation of carbon monoxide complex with the reduced form of hemoprotein led to 60–80% inhibition of oxygenase reactions, indicating the leading role of reduced heme iron in generating active oxygen species by flavocytochromes.