Figure 1.

Activation of GTPase activity by the ribosome. (a) GTPase activity of RsgA was activated by 70S ribosome (open rectangles) or the 30S subunit (closed circles) but not by the 50S subunit (open circles): 100 nM RsgA, 54 nM ribosome or its subunits and 50 μM [α-³²P]GTP were used. The ribosome or its subunits used had no detectable GTPase activity in the absence of RsgA. (b) The GTPase activity of RsgA was dependent on the concentration of ribosome: 100 nM RsgA, various concentrations of 70S ribosome and 50 μM [α-³²P]GTP were used.