Two-Site Model Parameters
| Site (i) . | KDi . | Ci . | Ei . | Fi . | KD(CR) . | KD(OR) . | KD(CA) . | KD(OA) . |
|---|---|---|---|---|---|---|---|---|
| 1 | 5.0 | 1.35 | 2.0 | 5.0 | 5.0 | 3.70 | 1.85 | |
| 2 | 70 | 1.6 | 2.3 | 70 | 43.8 | 30.4 | 19.0 |
| Site (i) . | KDi . | Ci . | Ei . | Fi . | KD(CR) . | KD(OR) . | KD(CA) . | KD(OA) . |
|---|---|---|---|---|---|---|---|---|
| 1 | 5.0 | 1.35 | 2.0 | 5.0 | 5.0 | 3.70 | 1.85 | |
| 2 | 70 | 1.6 | 2.3 | 70 | 43.8 | 30.4 | 19.0 |
Parameters that were varied to fit Mg2+ data (Fig. 5, A and B) for WT (Eq. 2) and E374A/E399N (Eq. 2 with K1 = 0). Remaining parameters (zJ, zL, J0, L0, D) were identical to those for 0 Mg2+ in Table I. These parameters predict ΔVhC values of −15.7 mV (WT, 10 Mg), −36.9 mV (WT, 100 Mg), −6.5 mV (E374A/E399N, 10 Mg), −24.4 mV (E374A/E399N, 100 Mg); similar to those measured in Fig. 3 F.