AMINOTRIAZOLE METABOLISM IN CIRSIUM ARVENSE (L.) SCOP. AND PISUM SATIVUM L.

Abstract

Summary. Excised leaves as well as intact plants of Canada thistle (Cirsium arvense (L.) Scop.) metabolized 3‐amino‐l,2,4‐triazole (aminotriazole) to three major products, Unknowns II, 1a and 1b. Unknown II was identical to β‐(3‐amino‐l,2,4‐triazolyl‐l‐)α‐alanine. Unknowns 1a and 1b, previously described as one product, were separated by electrophoresis and thin layer chromatography. Unknown 1a appeared to be a metabolic product of Unknown II while Unknown 1B was derived from Unknown 1a. An enzyme preparation from pea (Pisum sativum L. cv. Thompson Laxton) seedlings capable of synthesizing tryptophan from indole and serine was also able to metabolize aminotriazole. Tryptophan synthesis with the enzyme preparation was inhibited by aminotriazole and evidence suggests that aminotriazole metabolism may follow a similar pathway to tryptophan synthesis. Métabolisme de l'aminotriazole chez Cirsium arvense (L.) Scop, et Pisum sativum L.

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