METABOLISM OF PHENYLPROPANOID COMPOUNDS IN SALVIA: I. BIOSYNTHESIS OF PHENYLALANINE AND TYROSINE

Abstract

C14-Labelled shikimic acid, L-phenylalanine, D-phenylalanine, L-tyrosine, and cinnamic acid were fed separately to leafy cuttings of salvia. After a metabolic period of 24 hours the free and bound phenylalanine, tyrosine, and glutamic acid were isolated from the stems, and their specific activities measured. Shikimic acid was found to be a good precursor of both phenylalanine and tyrosine. There was little interconversion of phenylalanine and tyrosine, and hardly any oxidative breakdown of these compounds to glutamic acid precursors. D-Phenylalanine was metabolized more slowly than L-phenylalanine but it was superior to cinnamic acid as a precursor of bound phenylalanine and tyrosine.