FIGURE 5.

Processive polymerization rates. A, multiple nucleotide incorporations were carried out to measure the time taken by Pol2_core exo⁻ and Pol ϵ exo⁻ to incorporate 30 nucleotides under single-turnover conditions. Excess 50/80-mer (100 nm) was preincubated with enzyme (60 nm) and rapidly mixed with Mg²⁺ and physiological dNTP concentrations. B, the amount of remaining substrate (50-mer in red) and each intermediate product (51-mer in red, 52-mer in yellow, 53-mer in maroon, 54-mer in green, 55-mer in light blue, and 56-mer in black) were plotted with the KinTek global simulation software using a model defining the incorporation of the first six nucleotides and six DNA dissociation events. The polymerization rate constants obtained for Pol2_core exo⁻ and Pol ϵ exo⁻ are listed in Table 6.