Biosynthesis of S-Methylcysteine in Radish Leaves1
Open Access
- 1 October 1966
- journal article
- research article
- Published by Oxford University Press (OUP) in Plant Physiology
- Vol. 41 (8) , 1301-1307
- https://doi.org/10.1104/pp.41.8.1301
Abstract
Investigation on the biosynthesis of S-methyl-L-cysteine in radish leaves has shown that it is formed by the methylation of cysteine. This conclusion is based on: A) the relatively high recovery of radioactivity in methylcysteine sulfoxide after the administration of cysteine or methyl-labeled methionine to radish leaves; B) the nearly complete recovery of label from methyl-labeled methionine in the methyl group of methylcysteine sulfoxide; and C) the similarity in the ratio of tritium to 14C in methylcysteine sulfoxide and in its methyl group to this ratio in the methyl group of methionine given to radish leaves. Direct evidence for the synthesis of methylcysteine in radishes was obtained for the first time. Conclusive evidence against the formation of methylcysteine from serine and a thiomethyl group from methionine as suggested for garlic was the more efficient incorporation of the methyl group of methionine as compared to the sulfur atom into methylcysteine sulfoxide.This publication has 4 references indexed in Scilit:
- The reduction of S-methyl-l-cysteine sulfoxide and l-methionine sulfoxide in turnip and bean leavesBiochimica et Biophysica Acta (BBA) - General Subjects, 1966
- A Sensitive Qualitative Test for Sulphoxides on Paper ChromatogramsNature, 1963
- The formation of (+) S-methyl-l-cysteine sulfoxide from S-methyl-l-cysteine in crucifersBiochimica et Biophysica Acta, 1962
- ENZYMATIC FORMATION OF GLYCERYL AND PHOSPHOGLYCERYL METHYLTHIOL ESTERSJournal of Biological Chemistry, 1956