Figure 3.

DnaA-ADP is active in unwinding oriC^allADP, but not wild-type oriC. Purified supercoiled plasmid was incubated with the indicated concentrations of DnaA-ATP (A), or a mixture of DnaA-ATP and DnaA-ADP at the concentrations indicated in (B), and treated with P1 nuclease. Topological forms were separated by electrophoresis through agarose gels, followed by staining with ethidium bromide. The positions of uncut supercoiled, nicked and linearized forms are shown. The percentage of DNA converted to linear form was quantified.