Table 1. Effects of mutations on kinetic parameters.

	K′ ATP†	K0.5(Na)†	K0.5(K)†	K0.5(KEXT)‡	l50† (vanadate)	Catalytic turnover† (Vmax/EPmax)
α1	3.0(24)	1.04(14)	1.05(14)	1.10(25)	0.03(17)	1.67(17)
α2*	1.00	1.00	1.00	1.00	1.00	1.00
T345A	0.30	1.11	1.92	1.79	3.13	1.00
R689Q	0.90	1.06	0.21	0.52	6.22	0.44
M731T	0.42	1.19	0.33	0.57	27.3	0.19

Values shown are normalized to a value of 1.0 for the WT α2^* enzyme. Numbers in superscript refer to references from which the data (shown in italics) for α1 were taken.

^†Kinetic parameters are from assays of Na,K-ATPase hydrolytic activity.

^‡Kinetic parameters is from the assay of ouabain-sensitive K⁺ influx, whereby K_0.5(KEXT) refers to the K_0.5 for extracellular K⁺.