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Structure of a cytochrome P450-redox partner electron-transfer complex.

ABSTRACT: The crystal structure of the complex between the heme- and FMN-binding domains of bacterial cytochrome P450BM-3, a prototype for the complex between eukaryotic microsomal P450s and P450 reductase, has been determined at 2.03 A resolution. The flavodoxin-like flavin domain is positioned at the proximal face of the heme domain with the FMN 4.0 and 18.4 A from the peptide that precedes the heme-binding loop and the heme iron, respectively. The heme-binding peptide represents the most efficient and coupled through-bond electron pathway to the heme iron. Substantial differences between the FMN-binding domains of P450BM-3 and microsomal P450 reductase, observed around the flavin-binding sites, are responsible for different redox properties of the FMN, which, in turn, control electron flow to the P450.

SUBMITTER: Sevrioukova IF

PROVIDER: S-EPMC26702 | biostudies-literature | 1999 Mar

REPOSITORIES: biostudies-literature

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Structure of a cytochrome P450-redox partner electron-transfer complex.

Sevrioukova I F IF Li H H Zhang H H Peterson J A JA Poulos T L TL

Proceedings of the National Academy of Sciences of the United States of America 19990301 5

The crystal structure of the complex between the heme- and FMN-binding domains of bacterial cytochrome P450BM-3, a prototype for the complex between eukaryotic microsomal P450s and P450 reductase, has been determined at 2.03 A resolution. The flavodoxin-like flavin domain is positioned at the proximal face of the heme domain with the FMN 4.0 and 18.4 A from the peptide that precedes the heme-binding loop and the heme iron, respectively. The heme-binding peptide represents the most efficient and ...[more]

PMID: 10051560

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