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Substrate binding induces structural changes in cytochrome P450cam.

ABSTRACT: The binding of (+)-camphor to cytochrome P450cam (P450cam) expels a cluster of waters at the active site, raising the redox potential of the haem to an extent that allows reduction by the electron-transfer system. This binding was reported to involve no significant structural changes in the protein. Here, two ferric P450cam structures partially complexed with (+)-camphor were determined by X-ray crystallography at 1.30-1.35 A resolution, revealing the structures of the substrate-free and substrate-bound forms. (+)-Camphor binding induces rotation of Thr101 to form a hydrogen bond that acts as a hydrogen donor to a peripheral haem propionate. This bonding contributes to the redox-potential change.

SUBMITTER: Sakurai K

PROVIDER: S-EPMC2635880 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Substrate binding induces structural changes in cytochrome P450cam.

Sakurai Keisuke K Shimada Hideo H Hayashi Takashi T Tsukihara Tomitake T

Acta crystallographica. Section F, Structural biology and crystallization communications 20090131 Pt 2

The binding of (+)-camphor to cytochrome P450cam (P450cam) expels a cluster of waters at the active site, raising the redox potential of the haem to an extent that allows reduction by the electron-transfer system. This binding was reported to involve no significant structural changes in the protein. Here, two ferric P450cam structures partially complexed with (+)-camphor were determined by X-ray crystallography at 1.30-1.35 A resolution, revealing the structures of the substrate-free and substra ...[more]

PMID: 19193991

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