Unit | Cell-attached low chloride (% coefficient of variation of the mean) | Outside-out high chloride (% coefficient of variation of the mean) | |
---|---|---|---|
α1 | s−1 | 3400 (13) | 2000 (11) |
β1 | s−1 | 4200 (22) | 2900 (51) |
α2 | s−1 | 2100 (12) | 2400 (5) |
β2 | s−1 | 28,000 (17) | 89,000 (4) |
α3 | s−1 | 7000 (18) | 3900 (25) |
β3 | s−1 | 129,000 (4) | 160,000 (8) |
γ1 | s−1 | 29,000 (10) | 13,000 (51) |
δ1 | s−1 | 180 (24) | 120 (11) |
γ2 | s−1 | 18,000 (14) | 14,000 (10) |
δ2 | s−1 | 6800 (6) | 4500 (10) |
γ3 | s−1 | 900 (26) | 3500 (35) |
δ3 | s−1 | 20,900 (3) | 17,000 (2) |
k− | s−1 | 300 (6) | 340 (9) |
k+ | m−1 · s−1 | 0.6 × 106 (6) | 1.0 × 106(fixed) |
kF− | s−1 | 1200 (12) | 1300 (7) |
kF+ | m−1 · s−1 | 150 × 106 (5) | 160 × 106 (30) |
d3slow+ | s−1 | 9 (22) | 11 (21) |
d3slow− | s−1 | 27 (31) | 20 (14) |
d3fast+ | s−1 | 140 (33) | 130 (29) |
d3fast− | s−1 | 198 (22) | 280 (16) |
d2fast+ | s−1 | 79 (24) | |
d2fast− | s−1 | 280 (29) | |
E1 | 1.3 (21) | 1.3 (49) | |
E2 | 13 (9) | 37 (9) | |
E3 | 20 (16) | 50 (21) | |
F1 | 60 × 10−2 (18) | 3 × 10−2 (50) | |
F2 | 0.40 (15) | 0.30 (16) | |
F3 | 27 (31) | 8 (33) | |
KR | μm | 520 (12) | 350 (9) |
KF | μm | 8 (14) | 13 (46) |
Kinetic rate estimates from single-channel fits: Average rate constants (±coefficient of variation of the mean) from the fit of the flip mechanism (Figure 1C) (Burzomato et al., 2004) to four independent sets of single-channel experiments (three concentrations per set) in the outside-out configuration are compared with the rates from Burzomato et al. (2004) (first column). Desensitization rates are estimated from the fits of 200 ms jumps to 3 mm glycine with low or high chloride in the pipette. The efficacies, the equilibrium constants for the flip states (Fn = δn/γn), and the dissociation equilibrium constants are reported at the bottom of the table.