Formation of Allantoin and Allantoic Acid from Adenine in Leaves of Acer saccharinum L.

Abstract

ALLANTOIN and allantoic acid have been shown to be major constituents of the xylem sap of many species of trees¹, and have been proposed as important trans-locatory forms of nitrogen^1,2. Most workers in ureide metabolism in plants are of the opinion that allantoin and allantoic acid are not formed primarily by purine catabolism, as in the case in animals, but are synthesized from simpler molecules such as urea, glycine, or glyoxylate^2–4. This communication presents evidence that allantoin and allantoic acid are readily formed from adenine in leaves of silver maple (Acer saccharinum L.).