Figure 4

DNA relaxation activity of the L. major WT and the strain genetically manipulated at the topS locus. 0.2 Micrograms of leishmanial extracts were incubated with 0.125 μg of RfI ΦX174 supercoiled DNA for 30 min at 37°C. Lanes 1 to 6 correspond to time-course experiments (0.5, 1, 5, 10, 15, 20 min). Lanes 7 to 12 correspond to a two-fold serial dilution assay of leishmanial extracts. A) WT; B) LmTopIB-overexpresing strain; C) (ΔtopS/ΔtopS) + topS strain; N, nicked plasmid; R, relaxed plasmids; S, supercoiled plasmids.