title: Quantitative analysis of the mitochondrial cytochrome P-450-linked monooxygenase system: NADPH-hepatoredoxin reductase, hepatoredoxin, and cytochrome P-450s27 in livers of patients with cerebrotendinous xanthomatosis.
abstract: We studied the mitochondrial cytochrome P-450-linked monooxygenase system in livers of two patients with cerebrotendinous xanthomatosis (CTX). The three components of this system, which catalyzes steroid 27-hydroxylation, NADPH-hepatoredoxin reductase, hepatoredoxin, and cytochrome P-450s27, were stained on a nitrocellulose sheet with antibodies against NADPH-adrenodoxin reductase, adrenodoxin, and cytochrome P-450scc, respectively, from bovine adrenocortical mitochondria. The concentrations of hepatoredoxin in the patients were not significantly different from a control, but the level of NADPH-hepatoredoxin reductase was three times that of the control. Cytochrome P-450s27 was not detected in the patients, but it was present (22.8 pmol/mg of protein) in the control liver. This implies that a defect of mitochondrial cytochrome P-450s27 prevents steroid 27-hydroxylation of hepatic mitochondria in patients with CTX.
mesh_terms: D000302:Adrenal Cortex / Q000201:enzymology / Q000648:ultrastructure; D000328:Adult; D000818:Animals; D001927:Brain Diseases / Q000150:complications / Q000201:enzymology*; D002417:Cattle; D053493:Cholestanetriol 26-Monooxygenase; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis* / Q000378:metabolism; D005260:Female; D005287:Ferredoxin-NADP Reductase / Q000032:analysis*; D005288:Ferredoxins / Q000032:analysis*; D006801:Humans; D007527:Isoenzymes / Q000032:analysis*; D008930:Mitochondria, Liver / Q000201:enzymology*; D009247:NADH, NADPH Oxidoreductases / Q000032:analysis*; D010105:Oxygenases / Q000032:analysis*; D013250:Steroid Hydroxylases / Q000378:metabolism; D013710:Tendons; D014973:Xanthomatosis / Q000150:complications / Q000201:enzymology*
chemical_list: D005288:Ferredoxins; D007527:Isoenzymes; C041734:hepatoredoxin; D003577:Cytochrome P-450 Enzyme System; D010105:Oxygenases; D013250:Steroid Hydroxylases; C506831:CYP27A1 protein, human; D053493:Cholestanetriol 26-Monooxygenase; D005287:Ferredoxin-NADP Reductase; D009247:NADH, NADPH Oxidoreductases