1E6E

ADRENODOXIN REDUCTASE/ADRENODOXIN COMPLEX OF MITOCHONDRIAL P450 SYSTEMS

Summary for 1E6E

• Entry DOI: 10.2210/pdb1e6e/pdb
• Related: 1AYF 1CJC 1CJE 1E1K 1E1L 1E1M 1E1N
• Descriptor: NADPH\:ADRENODOXIN OXIDOREDUCTASE, ADRENODOXIN, FLAVIN-ADENINE DINUCLEOTIDE, ... (6 entities in total)
• Functional Keywords: flavoenzyme, electron transferase, oxidoreductase, [2fe-2s]ferredoxin, adrenodoxin, electron transport, complex
• Biological source: BOS TAURUS (BOVINE); More
• Total number of polymer chains: 4
• Total formula weight: 131187.34

Authors

Mueller, J.J.,Lapko, A.,Bourenkov, G.,Ruckpaul, K.,Heinemann, U. (deposition date: 2000-08-15, release date: 2001-08-09, Last modification date: 2023-12-13)

Primary citation

Mueller, J.J.,Lapko, A.,Bourenkov, G.,Ruckpaul, K.,Heinemann, U.
Adrenodoxin Reductase-Adrenodoxin Complex Structure Suggests Electron Transfer Path in Steroid Biosynthesis.
J.Biol.Chem., 276:2786-, 2001

PubMed Abstract: The steroid hydroxylating system of adrenal cortex mitochondria consists of the membrane-attached NADPH-dependent adrenodoxin reductase (AR), the soluble one-electron transport protein adrenodoxin (Adx), and a membrane-integrated cytochrome P450 of the CYP11 family. In the 2.3-A resolution crystal structure of the Adx.AR complex, 580 A(2) of partly polar surface are buried. Main interaction sites are centered around Asp(79), Asp(76), Asp(72), and Asp(39) of Adx and around Arg(211), Arg(240), Arg(244), and Lys(27) of AR, respectively. In particular, the region around Asp(39) defines a new protein interaction site for Adx, similar to those found in plant and bacterial ferredoxins. Additional contacts involve the electron transfer region between the redox centers of AR and Adx and C-terminal residues of Adx. The Adx residues Asp(113) to Arg(115) adopt 3(10)-helical conformation and engage in loose intermolecular contacts within a deep cleft of AR. Complex formation is accompanied by a slight domain rearrangement in AR. The [2Fe-2S] cluster of Adx and the isoalloxazine rings of FAD of AR are 10 A apart suggesting a possible electron transfer route between these redox centers. The AR.Adx complex represents the first structure of a biologically relevant complex between a ferredoxin and its reductase.

PubMed: 11053423
DOI: 10.1074/JBC.M008501200

Experimental method

X-RAY DIFFRACTION (2.3 Å)