FORMATION OF DIPEPTIDES FROM AMINO-ACIDS AND THE 2'(3')-GLYCYL ESTER OF AN ADENYLATE

The yields of dipeptide obtained from the reaction of 0.2M 2′(3′)-O-(glycyl)-adenosine-5′-(O-methylphosphate) and 0.2M amino acid at pH 8.2 ranged from 0.1% to 35.5% for a group of 15 amino acids. The yields of glyser (35.3%), gly-cys (11.8%) and gly-thr (5.4%) were considerably greater than dipeptide yields obtained from any of the other 12 amino acids (≦ 1.7%). Aminolysis of 0.05M 2′(3′)-O-(glycyl)-adenosine-5′-(O-methylphosphate) by 0.4M serine ethyl ester yielded 53% glycylserine diketopiperazine, via N-(glycyl)-serine ethyl ester as a transient intermediate. The prebiotic significance of these reactions is discussed. © 1979 Springer-Verlag.