Enzymatic conversion of 16-hydroxypalmitic acid into 10,16-dihydroxypalmitic acid in [formula omitted

Abstract

A cell-free system prepared from epidermal extracts of young Vicia faba leaves catalyzed conversion of 16-hydroxypalmitic acid into 10,16-dihydroxypalmitic acid. The enzymatic product was identified by radio gas chromatographic analysis of its chromic acid oxidation products. The cofactors for the C-10 hydroxylation were ATP, CoA, NADPH and O 2 and the pH optimum was near 7.3. This mixed function oxidase type enzyme is novel in that it catalyzed hydroxylation in the middle of a saturated fatty chain of an activated fatty acid and this is a key reaction involved in the biosynthesis of cutin.