Abstract
Acetate-1-C14 was incorporated by mung bean mitochondria into glutamic acid and ornithine. Carbon-14 was located only in the carboxyl groups of glutamic acid and the same isotopic distribution was found in ornithine. delta-Ornithine-glutamate transaminase was present. The synthesis of citrulline involved the intermediate formation of carbamyl phosphate and the transfer of a carbamyl group to ornithine.