FIG 2.

(A) Time course of nucleotide incorporation by the wild-type (WT) NS5B and C-terminal domain mutants. Note the distinct lag with wild-type NS5B at the beginning of the time course (0 to 10 min). All assays were carried out in triplicate, and errors were negligible. Reaction conditions are detailed in Materials and Methods. (B) Single-cycle activity assays with NS5B-Δ21 and C-terminal domain mutants. All assays were carried out in triplicate, and errors were negligible. NMP, nucleotide monophosphate.