Table 1.
Parameters describing the voltage-dependent transition rates in the 2-state kinetic model, fitted to data in Fig. 2
| Parameter | n | α0 (s−1) | zα | β0 (s−1) | zβ |
|---|---|---|---|---|---|
| E268A | 10 | 177 ± 15 | 0.51 ± 0.01 | 15458 ± 1315 | 0.80 ± 0.03 |
| E268A, cooled | 9 | 110 ± 14 | 0.48 ± 0.02 | 9178 ± 1383 | 0.67 ± 0.06 |
| E268A/S520T | 8 | 357 ± 31 | 0.41 ± 0.01 | 18304 ± 1935 | 0.93 ± 0.03 |
| E268A, MeSO4− | 10 | 112 ± 12 | 0.48 ± 0.02 | 50647 ± 1857 | 0.63 ± 0.01 |
Values are means ± se; n is the number of cells; α0 is the inactive-to-active rate at 0 mV; β0 is the reverse rate at 0 mV; and zα and zβ are their respective voltage dependence. Data represent, from top to bottom, recordings from cells expressing E268A CLC-5, recordings at 5°C below room temperature, cells expressing the double E268A/S520T CLC-5 mutant, and recordings of E268A CLC-5 in the Cl−-free, methanesulfonate-based extracellular solution.