   1.14.14.133 | in complex with substrate 1,8-cineole, to 1.7 A resolution, and comparison with P450cam, EC 1.14.15.1. The active site of cytochrome P450cin is substantially different from that of cytochrome P450cam in that the B' helix, essential for substrate binding in many cytochrome P450s, is replaced by an ordered loop that results in substantial changes in active site topography. Cytochrome P450cin does not have the conserved threonine, Thr252 in cytochrome P450cam. Instead, the analogous residue in cytochrome P450cin is Asn242, which provides the only direct protein H-bonding interaction with the substrate. Cytochrome P450cin uses a flavodoxin-like redox partner to reduce the heme iron rather than the more traditional ferredoxin-like Fe2S2 redox partner used by cytochrome P450cam |
