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1cjc
From Proteopedia
STRUCTURE OF ADRENODOXIN REDUCTASE OF MITOCHONDRIAL P450 SYSTEMS
Overview
Adrenodoxin reductase is a monomeric 51 kDa flavoenzyme that is involved in the biosynthesis of all steroid hormones. The structure of the native bovine enzyme was determined at 2.8 A resolution, and the structure of the respective recombinant enzyme at 1.7 A resolution. Adrenodoxin reductase receives a two-electron package from NADPH and converts it to two single electrons that are transferred via adrenodoxin to all mitochondrial cytochromes P 450. The structure suggests how the observed flavin semiquinone is stabilized. A striking feature is the asymmetric charge distribution, which most likely controls the approach of the electron carrier adrenodoxin. A model for the interaction is proposed. Adrenodoxin reductase shows clear sequence homology to half a dozen proteins identified in genome analysis projects, but neither sequence nor structural homology to established, functionally related electron transferases. Yet, the structure revealed a relationship to the disulfide oxidoreductases, permitting the assignment of the NADP-binding site.
About this Structure
1CJC is a Single protein structure of sequence from Bos taurus. Full crystallographic information is available from OCA.
Reference
The structure of adrenodoxin reductase of mitochondrial P450 systems: electron transfer for steroid biosynthesis., Ziegler GA, Vonrhein C, Hanukoglu I, Schulz GE, J Mol Biol. 1999 Jun 18;289(4):981-90. PMID:10369776 Page seeded by OCA on Fri May 2 12:47:50 2008
