Effect of acetone on aniline hydroxylation by a reconstituted system

Acetone stimulated NADPH-dependent aniline hydroxylation catalysed by cytochrome P-450 purified from phenobarbital-treated rats. No activation by acetone occurred in a reconstituted system containing cytochrome P-448 purified from 3-methylcholanthrene-treated rats. Cumene hydroperoxide-supported aniline hydroxylation catalysed by cytochrome P-450 was not increased by the addition of acetone at the concentration which stimulated NADPH-dependent aniline hydroxylation in the reconstituted system. The NADPH-dependent cytochrome P-450 reduction was stimulated by acetone in the presence or absence of aniline. On the other hand, acetone did not exhibit any stimulatory effect on NADPH-dependent reduction of cytochrome P-448. The stimulatory effect of acetone on aniline hydroxylation was decreased with increasing pH of the reaction media. Furthermore, in the system containing cytochrome P-450, the ratio of product to hydrogen peroxide formation was virtually unchanged by the addition of acetone.