Skip to main content
. 2018 May 2;46(12):6099–6111. doi: 10.1093/nar/gky343

Figure 4.

Figure 4.

ComM exhibits helicase activity in vitro. (A) A representative forked substrate helicase assay with increasing concentrations of purified ComM. This forked substrate has 20 bp of annealed sequence and 25 bp tails. Concentrations of ComM used (in hexamer) were 0, 10, 25, 37.5, 50, 75, 100, 150, 200 and 250 nM. Images were quantified and plotted as indicated. (B) Helicase assay using forked DNA substrate with the indicated purified protein (100 nM Pif1 and 250 nM ComM/ComMK224A hexamer) in the presence of 5 mM ATP (Columns 1, 2 and 3) or ATPγS (Column 4). (C) Helicase assays using forked DNA substrates that accommodate enzymes of either directionality or that can only be unwound by 5′ to 3′ or 3′ to 5′ activity. Directional substrates contained one ssDNA tail that is inverted relative to the remainder of the strand (inverted portion indicated in gray on the schematic above bars), thus, preventing helicase activity in one direction. Substrates were incubated with 100 nM purified ComM (hexamer), 10 nM Pif1, or 50 nM SftH. All data are shown as the mean ± SD and are the result of at least three independent replicates. ***P < 0.001.