FIGURE 9.

PipX effect on the P_II-NAGK interaction. For SPR measurements NAGK was bound to FC2 of a Ni²⁺-loaded NTA sensor chip (see “Experimental Procedures”), and FC1 was used as a control. The response difference (ΔRU) between FC2 and FC1 is shown. A, association of P_II-NAGK complex influenced by PipX and effectors; 100 nm P_II was preincubated with 1 mm ATP (solid line), 1 mm ATP + 100 nm PipX (dotted line), 1 mm ADP (dashed line), or 1 mm ADP + 100 nm PipX (dot-dot-dashed line) and afterward injected onto immobilized NAGK. B, association of P_II-NAGK complex influenced by PipX and ATP and ADP at different ratios: 1 mm ATP + 1 mm ADP without PipX (solid line), 1 mm ATP + 1 mm ADP + 100 nm PipX (dotted line), 1 mm ATP + 2 mm ADP (dashed line), and 1 mm ATP + 2 mm ADP + 100 nm PipX (dot-dot-dashed line).