THE BIOGENESIS OF ALKALOIDS: XXIII. THE ROLE OF PROLINE AND ORNITHINE IN THE BIOGENESIS OF STACHYDRINE

Abstract

When methionine-Me-14C, pyridoxine, and folic acid were fed to growing alfalfa, the stachydrine isolated from the plant was radioactive. This observation supports the assumption that stachydrine arises from proline by methylation since pyridoxine has been shown to induce the formation of proline from ornithine in the plant. However, the administration of labelled ornithine, pyridoxine, folic acid, and methionine to alfalfa failed to produce the radioactive alkaloid. Similar experiments were performed in which methionine-Me-14C and folic acid, methionine-Me-14C and pyridoxine, and finally methionine-Me-14C alone were fed to alfalfa, and in each case the stachydrine isolated from the plant was radioactive, while the homostachydrine remained inactive. Feeding proline-carboxyl-14C to alfalfa failed to produce radioactive stachydrine. It must be concluded that in alfalfa which is 2 to 3 weeks old, stachydrine is actively synthesized although homostachydrine is not. The implications of these observations are discussed.