期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1977
卷号：74
期号：12
页码：5477-5481
DOI：10.1073/pnas.74.12.5477
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：A CO-binding heme protein was solubilized and partially purified from the inner membrane fraction of rat liver mitochondria by a modification of a method [Imai, Y. & Sato, R. (1974) Biochem. Biophys. Res. Commun. 60, 8-14] developed to purify cytochrome P-450 from liver microsomes. The partially purified preparation contained protoheme and its spectral properties are characteristic of the heme proteins of the cytochrome P-450 family. The isolated cytochrome P-450 preparation could reconstitute a CO-sensitive, NADPH-dependent 26-hydroxylation activity for 5{beta}-cholestane-3,7,-12-triol when supplemented with NADPH-adrenodoxin reductase and adrenodoxin, both purified from bovine adrenocortical mitochondria. Unlike a cytochrome P-450 purified from liver microsomes of drug-untreated rats, however, the liver mitochondrial cytochrome P-450 could not catalyze NADPH-dependent benzphetamine N-demethylation in the presence of adrenodoxin reductase and adrenodoxin or function with the purified microsomal NADPH-cytochrome c reductase plus Emulgen 913 as an electron-donating system. It is concluded that the rat liver inner mitochondrial membrane houses a species of cytochrome P-450 functional in 5{beta}-cholestane-3,7,12-triol 26-hydroxylation.
关键词：heme protein ; liver mitochondria ; bile acid ; cholestanetriol 26-hydroxylase
