Metabolism of xenobiotics by Beauveria bassiana

Abstract

1. Diazepam, warfarin and testosterone were metabolized by whole resting cells of the fungus Beauveria bassiana IMI 12939 via oxidative reactions such as hydroxylation and N-demethylation. 2. Metabolism of each substrate was inhibited by the cytochrome P450 inhibitors SKF-525A and metyrapone, consistent with the involvement of this enzyme system in the metabolism of these drugs by B. bassiana. 3. Substrate concentration-dependent inhibition was observed during diazepam metabolism by this organism, as has been observed in some mammalian systems. 4. Unlike most mammalian P450 systems, the warfarin-metabolizing activity of B. bassiana could not be induced by growing the organism in the presence of phenobarbitone, beta-naphthoflavone, 3-methylcholanthrene, 1-benzylimidazole or warfarin. 5. Overall findings indicate that B. bassiana possesses an oxidative metabolizing system capable of producing metabolites found in mammalian systems.