. 2005 Mar 4;88(5):3348–3359. doi: 10.1529/biophysj.104.055913

TABLE 1.

Overview of the equilibrium dissociation constants of the H,K-ATPase determined from the experiments presented

Reaction	Constant	Fit value	Determination by
E₁ ↔ HE₁	pK_H,1	6.7	pH titration without K⁺; Fig. 3 A
HE₁ ↔ H₂E₁	pK_H,2	≤4.5
E₁ ↔ KE₁	K_K,1	11 mM	pH and K⁺ titrations in E1; Fig. 3 A
KE₁ ↔ (K₂)E₂	K_K,2	16 mM
P-E₂ ↔ P-E₂H	pL_H,1	6.7 ± 1	pH titration in the presence of ATP and without K⁺; Fig. 4 A
P-E₂H ↔ P-E₂H₂	pL_H,2	≤2
P-E₂ ↔ P-E₂K	L_K,1	0.11 mM	Enzyme activity; Fig. 5
P-E₂K ↔ P-E₂K₂	L_K,2	0.11 mM

Constants were used to fit the reaction scheme of Fig. 7 B to the experimental data of Figs. 3 and 4. The temperature of the experiments was 18.5 ± 0.5°C. (pK = 10^−K, pL = 10^−L).