(B) Overview of the 8-oxo-dG:dC extension complex. The 39-kDa catalytic domain (8-kDa subdomain not shown for clarity) is colored by subdomain: fingers (salmon), palm (yellow) and thumb (purple). The polymerase is in complex with a 1-nt gapped 16-mer oligo (grey) and an incoming dUMPNPP (magenta). The primer terminal dC and 8-oxo-dG are shown in cyan and magenta, respectively. Key residues that form the primer terminal base pair binding pocket (N513, R517 and Glu529) and are involved in catalysis (D427, D429 and D490) are shown in black. The nucleotide binding metal (B) is shown in neon. 