Comparison of the crystal structures of wt and the Y567A mutant in complex with anti-8-oxoG:dCTP (14). A. Superimposed palm domains showing that the Y567A substitution resulted in a shift of G568 by ~ 0.7 Å laterally toward Y416, relative to wt. Residues of the Y567A mutant and wt are shown in yellow and orange, respectively, and the individual residues Y567 and Y567A are shown in gray and magenta, respectively. The nascent base-pair in the wt and Y567A mutant structures are shown in silver and blue, respectively. B. Schematic illustration of the spatial relationship between G568 and the nascent base-pair as shown in (A).