Purification and properties of cytochrome P-450 (SCC) from pig testis mitochondria.
Cytochrome P-450 was purified from pig testis mitochondria to a specific content of 13.1 n mol/mg of protein. The purified preparation was found to contain a single species of P-450, on sodium dodecyl sulfate polyacrylamide gel electrophoresis, with an apparent molecular weight of about 53000 +/- 2000. The cholesterol side chain-cleavage system could be reconstituted by mixing the purified cytochrome P-450, adrenodoxin reductase, adrenodoxin, cholesterol and NADPH. The rate of conversion of cholesterol to pregnenolone was 6.2 n mol/min/n mol of P-450 under the conditions employed. The absorption spectrum of the oxidized cytochrome P-450 had maxima at 416, 530 and 568 nm. The reduced CO-complex of the cytochrome P-450 exhibited an absorption maximum at 448 nm. The purified P-450 was subjected to microsequence analysis and its NH2-terminal amino acid sequence was found to show considerable homology with that of bovine adrenal P-450 (SCC).
Kuwada
M
M
Department of Biochemistry, School of Medicine, Kitasato University, Kanagawa, Japan.
Kitajima
R
R
Suzuki
H
H
Horie
S
S
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002786:Cholesterol Side-Chain Cleavage Enzyme / Q000302:isolation & purification* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D007700:Kinetics; D008297:Male; D008928:Mitochondria / Q000201:enzymology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D012689:Sequence Homology, Nucleic Acid; D013053:Spectrophotometry; D013552:Swine; D013737:Testis / Q000201:enzymology*
D002786:Cholesterol Side-Chain Cleavage Enzyme