Fig. 3.

Active site titration of hPolε at 20 °C. A pre-incubated solution of hPolε (50 nM) and increasing concentrations of 5′-radiolabeled D-1 DNA (10–80 nM) was rapidly mixed with dTTP (5 μM). All reactions were quenched after 100 ms with the addition of 0.37 M EDTA. The data were fit to Eq. (2) to yield a $K_{\mathrm{d}}^{\text{DNA}}$ of 33 ± 5 nM and _d an enzyme active concentration of 9.0 ± 0.7 nM.