FIGURE 5.

Light scattering and phosphate release assays demonstrate that pB171 ParM is unstable in limiting concentrations of nucleotide and rapidly hydrolyzes nucleotide and releases phosphate. A and B, assembly of pB171 ParM in various concentrations of ATP (A) and GTP (B). C–F, phosphate release assays. The amount of phosphate released by 5 μm pB171 ParM polymerized in 1 mm ATP (C), 1 mm GTP (D), 0.1 mm ATP (E), or 0.1 mm GTP (F) are plotted versus time (closed squares). Parallel assembly reactions were monitored with light scattering using the same stock protein solutions (closed circles). Buffer conditions for all experiments in this figure are the same as those used for the experiment in Fig. 4.