Hepatic mitochondrial cytochrome P-450: Isolation and functional characterization
AUTOR(ES)
Sato, R.
RESUMO
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 5β-cholestane-3α,7α,-12α-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 5β-cholestane-3α,7α,12α-triol 26-hydroxylation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=431771Documentos Relacionados
- Apocytochrome P-450: reconstitution of functional cytochrome with hemin in vitro.
- Rapid conformational changes of cytochrome P-450: Effect of dimyristoyl lecithin
- Primary structure of a cytochrome P-450: Coding nucleotide sequence of phenobarbital-inducible cytochrome P-450 cDNA from rat liver
- Primary structure of a cytochrome P-450: coding nucleotide sequence of phenobarbital-inducible cytochrome P-450 cDNA from rat liver.
- Mechanisms of hydroxylation by cytochrome P-450: metabolism of monohalobenzenes by phenobarbital-induced microsomes.