Peptidyl transfer RNA VI. The chemical synthesis of tri- and tetrapeptidyl transfer RNA

A general method for the preparation of tripeptidyl-tRNA is described. The method involves a reaction between N-hydroxysuccinimide ester of N-monomethoxytrityldipeptide and aminoacyl-tRNA. The monomethoxytrityl group is removed from the blocked peptidyl-tRNA under very mild conditions (5% dichloroacetic acid for 5 min at 4°) leaving the tRNA intact. When N-blocked carboxyl-activated tripeptide was reacted with aminoacyl-tRNA and the product formed was treated with dichloroacetic acid, a tetrapeptidyl-tRNA was obtained. The peptidyl-tRNA's described in this communication contained only bifunctional amino acids such as glycine, alanine, valine and phenylalanine. The activated N-blocked dipeptides used were either composed of two identical amino acids as in alanylalanine or of two different amino acids as in glycylphenylalanine.