Figure 2.

Incorporation of 2′-deoxyuridine 5-(β-chlorovinyl)sulfone phosphate 28 into a DNA open template substrate (a) and a one-nucleotide gap substrate (b) by DNA polymerases. Lane 1 represents only substrate in both panels. Substrates were incubated with pol β or pol I at 37 °C for 15 min. In panel a, lanes 2–6 represent the reactions containing 1, 5, 10, 25, and 50 nM pol β along with 50 μM dTTP, respectively. Lanes 8–12 indicate the reactions containing various concentrations of pol β (1, 5, 10, 25, and 50 nM) with 50 μM 28. Lanes 7 and 13 represent the reactions containing 5 U pol I. In panel b, lanes 2–7 represent the reactions containing 0.5, 1, 5, 10, 25, and 50 nM pol β along with 50 μM dTTP, respectively. Lanes 9–14 indicate the reactions containing various concentrations of pol β (0.5, 1, 5, 10, 25, and 50 nM) with 50 μM 28. Lanes 8 and 15 represent the reactions containing 5 U pol I. Substrates were ³²P-labeled at the 5′-end of the upstream strand and are illustrated above the gels.