Partial purification and characterization of poly(dC)-dependent DNA polymerase and its stimulating factor

Poly(dC)-dependent dGMP incorporating activity without a primer molecule and its stimulating factor were partially purified by successive column chromatographies. Polymerase activity that was highly dependent on the stimulating factor was separated from similar activity that was not stimulated by this factor by native DNA-cellulose column chromatography. The factor stimulating activity was strictly dependent on dGTP as substrate and incorporated dGMP into the 3′-OH terminus of poly(dC). However, no terminal deoxynucleotidyl transferase (EC 2.7.7.31) activity was detected in the preparation. The activity also responded to heat-denatured calf thymus DNA and poly(dT) as template, although to a lesser extent. The activity was inhibited by dideoxyGTP and N-ethylmaleimide, and was decreased significantly by aphidicolin and β-lapachon.