FIGURE 2.

Time courses for autophosphorylation of ChpA constructs that do not contain the C-terminal receiver domain (ChpArec). The ChpA construct (1.4 μm) was incubated with [γ-³²P]ATP (150 μm) in 50 mm Tris, pH 7.5, 50 mm KCl, 5 mm MgCl₂, 2 mm DTT at room temperature. Aliquots were removed at designated times, and analyzed by SDS-gel electrophoresis followed by phosphorimaging analysis. Error bars reflect standard deviations of 2–4 replicates. ChpA HH− (closed diamonds); ChpA −H− (open squares); ChpA HA− (open triangles); ChpA AH− (closed triangles), and ChpA AA− (closed circles).