Table 2. Frequency of Reactive-Like Structural Characteristics in Different Enzyme Variantsa.
| variant | no Q136-NADPH H-bond | rotated E319 | eclipsed C5 |
|---|---|---|---|
| WT | 1.000 (0.521) | 1.000 (0.142) | 1.000 (0.239) |
| Q140M-T520D | 0.656 (0.341) | 5.654 (0.801) | 1.215 (0.290) |
| L501H | 1.593 (0.829) | 0.526 (0.075) | 1.520 (0.363) |
| T520D-L199H | 1.811 (0.943) | 6.288 (0.891) | 0.979 (0.234) |
| T520D | 0.850 (0.442) | 3.860 (0.547) | 1.329 (0.318) |
| S487A | 1.265 (0.659) | 0.704 (0.100) | 1.279 (0.306) |
| V258T-T520D | 1.810 (0.942) | 6.125 (0.868) | 0.814 (0.195) |
| M472Q | 1.221 (0.636) | 0.381 (0.054) | 1.400 (0.334) |
| A497S | 1.394 (0.726) | 1.472 (0.209) | 1.545 (0.369) |
a
Values indicate the fraction of conformations consistent with the reactive-like feature in the −160 to −130 fs time window across both reactive (R) and nonreactive (NR–0.4) pathways. Measurements are normalized by WT with raw values reported in parentheses (see Methods).