Enzymatic synthesis of oligodeoxyribonucleotides of defined sequence. Polynucleotide phosphorylase catalysed addition of deoxyribonucleotides to primers which are good or poor acceptors.

Analytical high-pressure anion-exchange chromatography on RPC-5 has been used to study the behaviour of a good primer, d(pT-T-A-G), and a poor primer, d(pT-T-T-T-T-T) in the E. coli polynucleotide phosphorylase-catalysed reactions of dADP, dCDP, dGDP and dTDP where the primer is extended, predominantly, by one or two nucleotides. The experiments provide some generalizations for obtaining optimal yields in preparative reactions. In the course of the experiments, examples of anomalous behaviour of oligonucleotides on RPC-5 were encountered and these are discussed.