Table 2. Determination of sequential binding of ATP to P_II-wt or P_II-ST‑V variant.

	Kd1 (µM)		Kd2 (µM)		Kd3 (µM)
PII-wt	4.8	±0.0	17.4	±1.5	92.8	±14.1
PII-ST‑V	2.3	±0.5	10.9	±4.0	57.7	±3.3

Mean values of three replicas of the calculated ATP dissociation constants for the P_II binding sites 1-3 and ±SEM are shown. The original isotherms are presented in Figure S2.