Kinetic Investigation of Reversible Reaction Between Methionine and Iodine: Improved Iodometric Determination of Methionine

Abstract

Rate studies of reactions discovered by Lavine involving reversible oxidation of methionine to dehydromethionine with iodine are presented. The data suggest that the initial iodine attack may occur either on the nitrogen or on the sulfur. The hydrolytic rate of dehydromethionine to the corresponding sulfoxide appears to be sufficiently fast to cause some inherent errors in the original method of assay for the amino acid. Rate studies of reactions discovered by Lavine involving reversible oxidation of methionine to dehydromethionine with iodine are presented. The data suggest that the initial iodine attack may occur either on the nitrogen or on the sulfur. The hydrolytic rate of dehydromethionine to the corresponding sulfoxide appears to be sufficiently fast to cause some inherent errors in the original method of assay for the amino acid.