Template catalysis of acetyl transfer reactions

Abstract

Acetyl adenylate, 2′(3′)-O- acetyl adenosine and 5′-O- acetyl adenosine, like adenosine itself, form ordered helices with polyuridylic acid in the presence of Na + and Mg 2+. The transfer of acetate from acetyl adenylate to [8- 14C]adenosine is facilitated in the presence of polyuridylic acid and occurs specifically to the 2′(3′)-position. Under the same condition, 2′(3′)-O- acetyl adenosine transfers acetate to the 5′-position of adenosine. However, 5′-O- acstyl adenosine transfers acetate to both the 2′(3′)- and 5′-positions of adenosine. These results establish that a polyuridylic acid template is capable of orienting adenosine derivatives in such a way as to bring about highly specific intramolecular acetyl transfer reactions.