A Laboratory Procedure for the Acetylation and Permethylation of Oligopeptides on the Microgram Scale

Abstract

Abstract The amino acid sequence of oligopeptides can be determined from the mass spectra of their volatile derivatives. A general procedure for the N-acetylation and N,O,S-permethylation of unknown peptides that do not contain arginine is described. The procedure is illustrated by the derivatization of lysyl-tyrosyl-glutamic acid. The mass spectrum of the resulting N a, N' -diacetyl-N a, N'-dimethyllysyl-N a, O-dimethyltyrosyl-Na-methyl glutamic acid α, β dimethyl ester (I)1 is given.