Figure 9.
Inhibition of ssDNA hydrolysis by DBP. Two 70-μl reaction mixtures containing 3 μg/ml [3H]ssDNA E. coli, 25 mM Tris, pH 8.3, 50 mM KCl, 5 mM MgCl2, 100 μg/ml BSA, 12.5% glycerol, and 2 mM DTT were assembled on ice. DBP was added to one mixture to final concentration of 40 μg/ml, and both mixtures were incubated for 15 min at 30ºC. To initiate hydrolysis, 9 ng of the complex of AcMNPV alkaline nuclease with LEF-3 (complex AN/L3) was added to each reaction and incubation at 30ºC was continued. The 20-μl portions were taken from the mixtures at 10, 20, and 45 min and the release of acid-soluble radioactivity from [3H]ssDNA was measured. The radioactivity of undigested sample (5020 cpm) was taken as 100%.