Figure 2.

Analytical gel filtration assay of various proteins was carried out without (A) and with (B) GTP-analog GppNHp. For experiment with the analog, 200 μM GppNHp was incubated with protein with a buffer containing 50 mM Tris, 100 mM KCl, and 5 mM MgCl₂, pH 8.0. The mixture was kept for at least 1 h before injecting into the column. The mobile phase contained the buffer and 200 μM GppNHp. In either case, the protein concentration was kept at 20 μM.