Enzymatic synthesis of deoxyribo-oligonucleotides of defined sequence. Properties of the enzyme.

A modified purification is described for an enzyme, from Escherichiacoli B, which polymerizes deoxyribonucleoside-5' diphosphates. Under appropriate conditions, the enzyme will add a single deoxyribonucleotide residue to a deoxyribo-oligonucleotide primer. At all stages, the enzyme activity copurified with the activity which will polymerize adenosine-5' diphosphate (polynucleotide phosphorylase). Studies of heat stability, the effect of various temperatures of reaction and of disc gel electrophoresis failed to provide evidence that the two activities are separable.