Modification of yeast ribosomal proteins. Methylation.

Two-dimensional polyacrylamide-gel electrophoretic analysis of yeast ribosomal proteins uniformly labelled in vivo with methyl-3H]methionine and 1-14C]methionine revealed that four ribosomal proteins are methylated, i.e. proteins S31, S32, L15 and L41. Lysine and arginine appear to be the predominant acceptors of the methyl groups. The degree of methylation ranges from 0.09 to 0.20 methyl group per modified ribosomal protein species.