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Ring-andN-hydroxylation of 2-acetamidofluorene by rat liver reconstituted cytochrome P-450 enzyme system.

ABSTRACT: The N- and ring-hydroxylation of 2-acetamidofluorene were studied with a reconstituted cytochrome P-450 enzyme from microsomal fractions of liver from both control and 3-methylcholanthrene-pretreated rats. Proteinase treatment and Triton X-100 solubilization were two important steps for partial purification of the cytochrome P-450 fraction. Both cytochrome P-450 and NADPH-cytochrome c reductase fractions were required for optimum N- and ring-hydroxylation activity. Hydroxylation activity was determined by the source of cytochrome P-450 fraction; cytochrome P-450 fraction from pretreated animals was severalfold more active than the fraction from controls. Formation of N-hydroxylated metabolites with reconstituted systems from both control and pretreated animals was greater than that with their respective whole microsomal fractions.

SUBMITTER: Lotlikar PD

PROVIDER: S-EPMC1165772 | biostudies-other | 1975 Sep

REPOSITORIES: biostudies-other

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Phospholipid requirement for 2-acetamidofluorene N-and ring-hydroxylation by hamster liver microsomal cytochrome P-450 enzyme system.

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