Figure 4.

(a) PgVPolX is a template-directed DNA polymerase. The four different template-primer structures used, differing in the templating base of the 1-nt gaps, are shown on the left. The assay was performed as described in Materials and Methods with 25 nM of the indicated substrate, 3 nM of PgVPolX and either 20 µM of the correct dNTP or 200 µM of each of the three incorrect dNTPs. (b) Insertion of different types of nucleotides by PgVPolX. The assay was performed as described in Materials and Methods in the presence of 25 nM of the substrate depicted on the top of the panel, 3 nM of PgVPolX and the indicated concentrations of nucleotides. Asterisks indicate the 5′ Cy5-labeled end of the primer strand.