Bacillus megaterium bound

Another Class II P-450 redox system that has been extensively studied is the cytosolic flavocytochrome P-450 BM3 from Bacillus megaterium. BM3 is the fusion of a soluble P-450 domain with CPR." " " The FAD of BM3 is reduced by NADPH the electrons are transferred to FMN and then finally to the substrate-bound P-450 domain." " BM3 is the fastest reported P-450 monooxygenase,with the rate of hydride transfer from NADPH to FAD and the rate of electron transfer from FMN to heme several-fold above the mammalian P-450 redox systems." The structure of the full-length protein has yet to be solved, but the structure of the FAD- and NADPH-binding domain has been determined." This domain closely resembles rat liver CPR and contains several conserved residues implicated in NADPH binding and flavin reduction. 

Kitazume, T., N. Takaya, N. Nakayama, and H. Shoun (2000). Fusarium oxysporum fatty acid subterminal hydroxylase (CYP505) is a membrane-bound counterpart of Bacillus megaterium P450BM3. J. Biol. Chem. 275, 39734-39740. 

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