Spectroscopic investigations of intermediates in the reaction of cytochrome P450(BM3)-F87G with surrogate oxygen atom donors.

Rapid mixing of substrate-free ferric cytochrome P450(BM3)-F87G with m-chloroperoxybenzoic acid (mCPBA) resulted in the sequential formation of two high-valent intermediates. The first was spectrally similar to compound I species reported previously for P450(CAM) and CYP 119 using mCPBA as an oxidant, and it featured a low intensity Soret absorption band characterized by shoulder at 370nm. This is the first direct observation of a P450 compound I intermediate in a type II P450 enzyme.