FIGURE 4.

The effect of the R123E mutant of DprA on binding to double-strand DNA (dsDNA). The dsDNA was annealed from RA-ssDNA₁ and labeled with biotin. The first lane of each picture contained free dsDNA without proteins. Different concentrations of DprA (1–20 μM) were combined with 0.5 μl of DNA substrate (biotin-labeled dsDNA) and incubated for 30 min at 30°C before the mixture was loaded on the gel. (A) Interaction between DprA and dsDNA. (B) Interaction between DprA^R123E and dsDNA. Samples were electrophoresed on an 8% non-denaturing PAGE gel and detected by fluorography.