Table 1. Dwell state kinetics.
Form | Michaelis Menten fits | Dwell analysis | ||||||
---|---|---|---|---|---|---|---|---|
vmax (rev s−1) | Km (μM) | kATP (s−1 μM−1) | n | kATP (s−1 μM−1) | k2 (ms)−1 | k3 (ms)−1 | n | |
Wild type | 586 ± 24 | 62 ± 9 | 28.3 ± 3.6 | 2177 | 18 ± 6 | 2.5 ± 1.2 | 4.3 ± 2.3 | 18, 28 |
γG278D | 582 ± 137 | 63 ± 33 | 27.6 ± 10.2 | 89 | 26 ± 2 | 2.6 ± 0.6 | 5.0 ± 1.7 | 4, 5 |
βV279F | 144 ± 13 | 24 ± 5 | 17.9 ± 2.8 | 537 | 15 ± 2 | 0.36 ± 0.08 | 2.3 ± 2.7 | 4, 8 |
αN67I | 248 ± 47 | 41 ± 12 | 18.0 ± 2.6 | 432 | 14 ± 3 | 0.46 ± 0.09 | 2.3 ± 0.7 | 7, 3 |
βR408G | 80 ± 11 | 10.0 ± 2.6 | 24.1 ± 4.0 | 439 | 19 ± 5 | 0.21 ± 0.08 | 1.3 ± 0.5 | 10, 17 |
αF405S | 336 ± 40 | 49 ± 11 | 20.4 ± 3.2 | 1044 | 16 ± 6 | 0.8 ± 0.6 | 2.0 ± 0.9 | 62, 40 |
γI270T | 377 ± 92 | 44 ± 15 | 25.7 ± 4.4 | 2190 | 22 ± 7 | 0.8 ± 0.5 | 2.5 ± 2.0 | 109, 27 |
βR408I | 69 ± 13 | 7.9 ± 2.5 | 26.4 ± 4.7 | 6519 | 23 ± 6 | 0.20 ± 0.07 | 3.3 ± 2.3 | 384, 51 |
Bacillus PS333 | 129 ± 22 | 15 ± 5 | 25.8 | |||||
E. coli6 | 449 ± 39 | 21.1 ± 1.0 | 43 ± 4 |
The results of the analysis from the Michaelis-Menten fits and the dwell time histogram analysis for wild type and the seven mutants screened. All values are quoted with 95% confidence intervals, with the exception of Bacillus PS3 and E. coli, where the values were sourced from previous studies as indicated in the table. The errors in these studies were typically quoted as standard deviations; for comparison to the 95% CIs listed here they have been multiplied by 1.96 for data where the number of degrees of freedom were unknown, or by the appropriate t-statistic where the number of degrees of freedom was known (2.45 to 1.96 for df = 6 to ∞). In some cases the error could not be calculated from the available data and has been left blank. The number of traces used is denoted by n. For the dwell analysis, the first value of n corresponds to the number of traces used to calculate kATP and the second value for the number of traces used to calculate k2 and k3.