Purification and characterization of cytochrome P-45014DM (lanosterol 14 alpha-demethylase) from pig liver microsomes.
Cytochrome P-45014DM, which catalyzes lanosterol 14 alpha-demethylation, from pig liver microsomes was purified to a state of virtually homogeneous by gel electrophoresis. Its apparent monomeric molecular weight was estimated to be 53,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the amino-terminal amino acid sequence was Gly-Leu-Leu-Thr-Gly(Leu)-Asp-Leu-Leu-Gly-Ile. When reconstituted with NADPH-cytochrome P-450-reductase, the enzyme showed a high activity for lanosterol and 24,25-dihydrolanosterol 14 alpha-demethylation. Furthermore, the oxygenated intermediates of 24,25-dihydrolanosterol 14 alpha-demethylation, 32-hydroxy-24,25-dihydrolanosterol and 32-oxo-24,25-dihydrolanosterol, were converted to the 32-nor compound, 4,4-dimethylcholesta-8,14-dien-3 beta-ol, by the reconstituted enzyme system.
Sono
H
H
Kyoritsu College of Pharmacy, Tokyo, Japan.
Sonoda
Y
Y
Sato
Y
Y
D000595:Amino Acid Sequence; D000818:Animals; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000302:isolation & purification* / Q000378:metabolism; D004789:Enzyme Activation; D007700:Kinetics; D008862:Microsomes, Liver / Q000201:enzymology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010088:Oxidoreductases / Q000037:antagonists & inhibitors / Q000302:isolation & purification* / Q000378:metabolism; D013054:Spectrophotometry, Atomic; D058886:Sterol 14-Demethylase; D013379:Substrate Specificity; D013552:Swine
D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System; D010088:Oxidoreductases; D058886:Sterol 14-Demethylase