Hinge domain fragment destabilizes bound MukB.
A, tailed, nicked DNA substrate is equivalent to the nicked DNA substrate. Top panel, MukB in the presence or absence of the wild-type hinge domain fragment was incubated with the biotinylated, tailed, nicked DNA substrate for 5 min at 37 °C and then analyzed by agarose gel electrophoresis. Bottom panel, densitometric tracings of the lanes of the gel shown in the top panel. B and C, hinge domain fragment destabilizes bound MukB. MukB was incubated on a rotator with tailed, nicked DNA substrate that had been bound to magnetic beads for 5 min at 37 °C. Either wild-type or KE,RE hinge domain fragment was then added, and the incubation continued for 30 min. The beads were then pulled down on a magnet, and the supernatant was removed. The protein present in the pellet (P) and supernatant (S) fractions were then assayed by SDS-PAGE. B, example of the SDS gel. C, distribution of MukB in the pellet and supernatant. The mean and standard deviation is shown for three independent experiments.