The flavoprotein component of the Escherichia coli sulfite reductase can act as a cytochrome P450c17 reductase.
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Zeghouf M, Defaye G, Fontecave M, Coves J
The flavoprotein component of the Escherichia coli sulfite reductase can act as a cytochrome P450c17 reductase.
Biochem Biophys Res Commun. 1998 May 29;246(3):602-5.
- PubMed ID
- 9618257 [ View in PubMed]
- Abstract
The flavoprotein component (SiR-FP) of the E. coli sulfite reductase was found to support 17 alpha-hydroxylation of pregnenolone in the presence of cytochrome P450c17. Half maximum activity is obtained for a 1:1 ratio of SiR-FP, expressed as monomer concentration, to P450c17. When compared to bovine NADPH-cytochrome P450 reductase, SiR-FP is about 12-15 times less efficient. P450c17 was demonstrated to interact specifically with the FMN-binding domain of the protein and the N-terminal part of SiR-FP is suspected to play a role in electron transfer. A cluster of negatively charged residues was found in SiR-FP by amino acid sequence comparison with rat cytochrome P450 reductase. These results argue in favour of the flavodoxin origin of the FMN-binding domain of SiR-FP.