Figure 2.

The ratio of correct versus incorrect nucleotide incorporation efficiency decreases during ribonucleotide extension by DNA polymerase η. A, chemical representation of deoxyribonucleoside (dN) and ribonucleoside (rN). Hydrogens on the sugar moieties have been removed for clarity. B, WT Pol η DNA polymerase correct versus incorrect nucleotide incorporation efficiencies during dN or rN extension in the presence of Mg²⁺ based on steady-state kinetics. The bars represent the mean of triplicate measurements for the catalytic efficiencies (k_cat/K_M) for incorporation of dATP (blue) and dGTP (red) opposite dT for WT Pol η. The errors bars represent the standard deviation for the measurements. The distance between the respective catalytic efficiencies represents a ratio of the efficiencies and is a measure of discrimination. Data are generated from Table S1. dGTP, deoxyribose guanine triphosphate; Pol η, DNA polymerase η.