Fat metabolism in higher plants. VIII. Saturated long chain fatty acid peroxidase.

In a previous communication (1) it was reported that an L-a-hydroxy aliphatic acid was required as a cofactor for the limited oxidation of palmitic acid by a soluble cytoplasmic protein fract,ion obtained by precipitation with ammonium sulfate from extracts of cotyledons of germinating peanuts. This fraction was designated supernatant enzyme. No additional cofactors were required, and activity was limited to the long chain saturated fatty acids. This paper will present results of experiments which indicate that a specific long chain saturated fatty acid peroxidase is responsible for the partial oxidation of palmitic acid to carbon dioxide. L-or-Hydroxy aliphatic acid serves as a substrate for trace concentrations of glycolic acid oxidase which, in oxidizing the substrate, generates HzOz. HzOz, in turn, participates in the peroxidation of the long chain saturated fatty acid. Evidence will also be presented which indicates that one of the reaction products is a long chain fatty aldehyde.