1ayf
From Proteopedia
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BOVINE ADRENODOXIN (OXIDIZED)
Overview
BACKGROUND: Adrenodoxin (Adx) is a [2Fe-2S] ferredoxin involved in steroid, hormone biosynthesis in the adrenal gland mitochondrial matrix of mammals., Adx is a small soluble protein that transfers electrons from adrenodoxin, reductase (AR) to different cytochrome P450 isoforms where they are, consumed in hydroxylation reactions. A crystallographic study of Adx is, expected to reveal the structural basis for an important electron transfer, reaction mediated by a vertebrate [2Fe-2S] ferredoxin. RESULTS: The, crystal structure of a truncated bovine adrenodoxin, Adx(4-108), was, determined at 1.85 A resolution and refined to a crystallographic R value, of 0.195. The structure was determined using multiple wavelength anomalous, dispersion phasing techniques, making use of the iron atoms in the, [2Fe-2S] cluster of the protein. The protein displays the compact (alpha +, beta) fold typical for [2Fe-2S] ferredoxins. The polypeptide chain is, organized into a large core domain and a smaller interaction domain which, comprises 35 residues, including all those previously determined to be, involved in binding to AR and cytochrome P450. A small interdomain motion, is observed as a structural difference between the two independent, molecules in the asymmetric unit of the crystal. Charged residues of, Adx(4-108) are clustered to yield a strikingly asymmetric electric, potential of the protein molecule. CONCLUSIONS: The crystal structure of, Adx(4-108) provides the first detailed description of a vertebrate, [2Fe-2S] ferredoxin and serves to explain a large body of biochemical, studies in terms of a three-dimensional structure. The structure suggests, how a change in the redox state of the [2Fe-2S] cluster may be coupled to, a domain motion of the protein. It seems likely that the clearly, asymmetric charge distribution on the surface of Adx(4-108) and the, resulting strong molecular dipole are involved in electrostatic steering, of the interactions with AR and cytochrome P450.
About this Structure
1AYF is a Single protein structure of sequence from Bos taurus with FES and GOL as ligands. Full crystallographic information is available from OCA.
Reference
New aspects of electron transfer revealed by the crystal structure of a truncated bovine adrenodoxin, Adx(4-108)., Muller A, Muller JJ, Muller YA, Uhlmann H, Bernhardt R, Heinemann U, Structure. 1998 Mar 15;6(3):269-80. PMID:9551550[[Category: [2fe-2s]ferredoxin]]
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