An inhibitor of microsomal oxidation from gut tissues of the honey bee ( Apis mellifera)

Abstract

1. 1. A potent inhibitor of microsomal oxidation was isolated and partially purified from the soluble fraction of gut tissue homogenates of adult worker honey bees. 2. 2. Inhibitory potency towards epoxidase, hydroxylase and O-demethylase activities in southern armyworm gut preparations was greater than towards the corresponding enzyme systems in rat liver microsomes. 3. 3. Inhibitory activity of the material was potentiated after digestion with pronase and reversed by digestion with ribonuclease (RNase T 1 or pancreatic RNase). 4. 4. Inhibition was associated with a nucleic acid (RNA) moiety of a macromolecule, possibly a nucleoprotein, with a molecular weight of approximately 19,000. 5. 5. Some commercially available nucleic acids, including core and transfer RNA from baker's yeast and transfer RNA from Torula yeast, also inhibited epoxidase activtiy in southern armyworm gut preparations.