Kinetics of PMPA incorporation catalyzed by DNA pol α. Reaction mixtures containing pol α (4 U/ml) and PMPApp at various concentrations (left to right, lanes 2 to 8: 5, 25, 125, 250, 500, 750, and 1,500 μM) were incubated in the presence of the template-primer DNA40/18 for 32 min at 37°C. Lane 1: primer only.