Components of the Electron Transport System in Adrenal Steroid Hydroxylase

Components of the electron transport system involved in steroid Ilo-hydroxylation in pig adrenal cortex are a flavoprotein (adrenodoxin reductase), a non-heme iron protein (adrenodozin), and possibly cytochrome Paw.Reconstitution of reduced nicotinamide adenine dinucleotide phosphate cytochrome Pdu reductase was achieved from soluble components.Adrenodozin contains 2 iron atoms and 2 moles of labile suliide per mole, has a molecular weight of approximately 20,000, and has a high oxidation-reduction potential.The iron atoms, which are ferric in the oxidized form, play a dual role: as a chromophore and as a center of asymmetry.Upon reduction, the environment of the iron of adrenodoxin is changed greatly as judged by spectral and optical rotatory properties.