Molecular properties of cytochrome P-45011 beta from adrenal cortex mitochondria.
Cytochrome P-45011 beta has been solubilized and partially purified from bovine adrenal cortex mitochondria using chromatography on Octyl-Sepharose CL-4B or DEAE-Sepharose CL-6B. The partially purified P-450 preparations were about 90% pure as judged by SDS-polyacrylamide gel electrophoresis. In the presence of purified preparations of adrenodoxin reductase and adrenodoxin, the partially purified P-450 preparations catalyzed NADPH-supported 11 beta-hydroxylation of unconjugated and sulphoconjugated deoxycorticosterone. In presence of Triton X-100 the partially purified cytochrome P-45011 beta had a Stoke's radius of 4.5 nm, a sedimentation coefficient of 3.1 S and a partial specific volume of about 0.85 cm3/g. These results indicate that the cytochrome P-45011 beta-Triton X-100 complex has a molecular weight of about 100 000 and that P-45011 beta bound about 1.1 g of Triton X-100 per g of protein. The P-45011 beta-Triton X-100 complex was catalytically active in hydroxylation reactions supported by NADPH or the hydroxylating agent ortho-nitroiodosobenzene, suggesting that the monomer of cytochrome P-45011 beta is an active form of the protein.
D000302:Adrenal Cortex / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D003577:Cytochrome P-450 Enzyme System / Q000302:isolation & purification* / Q000378:metabolism; D005287:Ferredoxin-NADP Reductase / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D008970:Molecular Weight; D013252:Steroid 11-beta-Hydroxylase / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity
D003577:Cytochrome P-450 Enzyme System; D013252:Steroid 11-beta-Hydroxylase; D005287:Ferredoxin-NADP Reductase