Table 4. Mutant AChR construct unliganded gating rates, equilibrium constants and free energies.
| Construct | f0(s−1) | b0(s−1) | E0mut | ΔG0Obs | E2mut/E2wt | ΔΔG2Cho | n |
|---|---|---|---|---|---|---|---|
| αN217K βL262T δL265T | 22.5 (6) | 786 (192) | 0.028 (0.01) | 2.1 (0.18) | 3.9 × 104 | −6.25 | 3 |
| αD97A βL262T δL265T | 19 (2) | 260 (17) | 0.073 (0.009) | 1.5 (0.07) | 1.7 × 105 | −7.08 | 2 |
| αL279W βL262T δL265T | 56 (4) | 633 (54) | 0.088 (0.01) | 1.4 (0.067) | 1.7 × 105 | −7.1 | 2 |
| αC418W βL262T δL265T | 85 (7) | 879 (92) | 0.095 (0.013) | 1.4 (0.08) | 1.6 × 105 | −7.1 | 5 |
| αP272A βL262T δL265T | 225 (58) | 889 (78) | 0.25 (0.06) | 0.8 (0.12) | 2.4 × 105 | −7.3 | 4 |
| αN217K βL262T δL265T εS450W | 35 (4.3) | 126 (13) | 0.27 (0.04) | 0.8 (0.09) | 2.9 × 105 | −7.43 | 2 |
| αY127F βL262T δL265T εS450W | 433 (14) | 752 (3.5) | 0.58 (0.02) | 0.3 (0.02) | 9.3 × 105 | −8.1 | 3 |
| αC418W βV266A δL265S | 5285 (236) | 120 (14) | 44.1 (5.1) | −2.2 (0.07) | 2.9 × 107 | −10.1 | 4 |
| βT456I δL265S εL261S | 269 (34) | 825 (93) | 0.32 (0.06) | 0.7 (0.11) | 8.4 × 105 | −8.0 | 2 |
| αA96V βV266A δL265S | 735 (55) | 160 (17) | 4.6 (0.22) | −0.9 (0.07) | 2.7 × 107 | −10.0 | 3 |
| αA96V βV266A εL261S | 6,925 (655) | 477 (126) | 14.6 (4.0) | −1.6 (0.16) | 2.1 × 107 | −9.9 | 5 |
Free energies are in kilocalories per mole. E0 = f0/b0; ΔΔG2Cho = −0.59*ln(E2mut/E2wt); ΔG0obs = −0.59*ln(E0); f0 and b0, unliganded forward and backward gating rate constants (±SEM, n patches); ΔΔG2Cho, change in gating free energy with two bound Cho molecules.