Figure 3.
Template DNA base pairing with the non-template DNA base at the –10th position promotes forward translocation. Pyrophosphorolysis rate constants were determined for TECs U10 (A) and U9 (B), and the fraction of the pre-translocated TEC was quantified assuming that pyrophosphorolysis in a stably pre-translocated TEC occurs at 2.4 ± 0.28 s−1. The TECs were formed with the non-template DNA strand (NDS) fully complementary to the template DNA strand (shaded bars) or with the NDS carrying dC-10, which creates a dC/dC mismatch in the DNA at the –10th position.