Three highly purified forms of rat liver microsomal cytochrome P-450 (P-450,, P-45Ob, P-450,) are shown to be distinct proteins based on comparisons of their amino acid compositions, automated sequence analyses of the first 19 amino acids, and carboxypeptidase analyses of the COOH-terminal sequences. These three forms of cytochrome P-450 were purified from liver microsomes of rats pretreated wi...

Treatment with beta-naphthoflavone (BNF) was found to induce 7-ethoxyresorufin O-deethylase and aryl hydrocarbon hydroxylase activities about 500-fold in the microsomal fraction of the rat ventral prostate but had no effect on aminopyrine N-demethylase or reduced nicotinamide adenine dinucleotide phosphate:cytochrome c reductase activities. Phenobarbital (PB) treatment did not alter any of thes...

Highly purified cytochromes P-450(LM2) and P-450(LM4) and partially purified P-450(LM1), P-450(LM3b), and P-450(LM7) from rabbit liver microsomes exhibit different catalytic activities in the metabolism of benzo[a]pyrene (BzP) and (-)-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene [(-)trans-7,8-diol] in a reconstituted enzyme system. The two highly purified cytochromes also exhibit differences i...

The 2,3,7,8-tetrachlorodibenzo-p-dioxin-inducible cytochrome P-450 gene family (P1-450 and P3-450 in the C57BL/6N mouse) has recently been localized to mouse chromosome 9. In the present study, HindIII-digested DNA from Chinese hamster, mouse, and 20 Chinese hamster X mouse somatic cell hybrids and subclones segregating hamster chromosomes was probed with the mouse P1-450 and P3-450 full-length...

1. The gene CYP102 encoding cytochrome P-450 BM-3 and subgenes encoding the cytochrome P-450 and cytochrome P-450 reductase domains have been cloned in Escherichia coli. 2. The protein products of these genes have been overexpressed and purified to homogeneity. 3. The cytochrome P-450 domain is purified in the ferric low-spin state, but is readily converted into the high-spin state by addition ...

Cytochrome P-450 was purified to apparent homogeneity from the brain microsomes of phenobarbital-treated rats. The specific content of the purified P-450 was 12.7 nmol/mg of protein. NADPH-cytochrome P-450 reductase (reductase) was also purified to apparent homogeneity from brain microsomes. The specific content was 34.7,mol of cytochrome c reduced/min per mg of protein. The reduced carbon mono...

Cytochrome P-450-catalyzed activation of cyclophosphamide to alkylating metabolites was studied in isolated rat liver microsomes and purified, reconstituted P-450 enzyme systems in order to identify the major enzymatic catalysts of drug activation in both uninduced and drug-induced liver tissue. P-450 form PB-4 (P-450 gene IIB1) activated cyclophosphamide with high efficiency [Vmax (app) = 18.2...

Cytochrome P-450-catalyzed activation of Cyclophosphamide to alkylating metabolites was studied in isolated rat liver microsomes and puri fied, reconstituted P-450 enzyme systems in order to identify the major enzymatic catalysts of drug activation in both uninduced and drug-induced liver tissue. P-450 form PB-4 (P-450 gene UBI) activated Cyclophospha mide with high efficiency [\ „¿ ,», (app...