The influence of the size and nature of basic activators on Clostridium perfringens polynucleotide phosphorylase-catalysed polyadenylic acid synthesis.

1. Basic oligo- and poly-(amino acids) stimulate polyadenylic acid synthesis by purified Clostridium perfringens polynucleotide phosphorylase (nucleoside diphosphate-polyribonucleotide nucleotidyltransferase, EC 2.7.7.8). 2. The effectiveness of the activators increases with chain length up to approx. 20-30 residues. 3. Polymers of the l and dl series are equally effective on a weight-for-weight basis. 4. l-Lysine, d-lysine, diethylamine and triethylamine, as hydrochlorides or hydrobromides, all stimulate the reaction markedly if their concentration is high enough. Their effect is similar to that of sodium chloride. 5. The size of the product depends primarily on the Mg(2+) concentration and basic polymers have a relatively limited effect on it. 6. Polyadenylic acid itself undergoes an Mg(2+)-catalysed non-enzymic hydrolysis.