| Transition . | αo (s−1) . | zαo(s−1) . | βo (s−1) . | zβo (s−1) . | c . |
|---|---|---|---|---|---|
| S0–S1 | 1,000 | 0.2 | 1,500 | −0.04 | 1 |
| S1–S2 | 134 | 0.02 | 280 | −0.05 | 1.5 |
| S2–A | 2,000 | 2 | 0.006 | −1.7 | |
| A–R | |||||
| pH 7.4 | 0.5 | 0 | 0.001 | 0 | |
| pH 6.5 | 10 | 0 |
| Transition . | αo (s−1) . | zαo(s−1) . | βo (s−1) . | zβo (s−1) . | c . |
|---|---|---|---|---|---|
| S0–S1 | 1,000 | 0.2 | 1,500 | −0.04 | 1 |
| S1–S2 | 134 | 0.02 | 280 | −0.05 | 1.5 |
| S2–A | 2,000 | 2 | 0.006 | −1.7 | |
| A–R | |||||
| pH 7.4 | 0.5 | 0 | 0.001 | 0 | |
| pH 6.5 | 10 | 0 |
Parameters for pH 6.5 were the same as those for pH 7.4, unless otherwise indicated. Forward rates were calculated as α = αo*exp(zα*VF/RT), and reverse rates were calculated as β = βo*exp(zβ*VF/RT). c reflects the cooperativity factor applied to the independent transitions. It was necessary to modify forward and backward rates between S2 and A states from those reported previously (Piper et al., 2003) to reproduce gating current properties during the longer durations used in the present study.