Table 2.
The specific catalytic efficiency of positive multiple mutants
| Substrate | Specific catalytic efficiency (kcat/Km) |
||||||||
|---|---|---|---|---|---|---|---|---|---|
| Native |
E251V |
Multiple mutants |
|||||||
| kcat/Km (M−1 × min−1) | Specific efficiency | kcat/Km (M−1 × min−1) | Specific efficiency | S320K/F243Y | S320K/P61E | S320K/E251V | E251V/P61E | S320K/E251V/P61E | |
| 1 | 1002.9 | 1 | 141.1 | 0.141 | 11.4 | 0.237 | 0.084 | 0.057 | 0.045 |
| 3 | 7231.0 | 1 | 3595.8 | 0.497 | 1.58 | 1.69 | 0.318 | 0.223 | 0.13 |
| 5 | 10070.9 | 1 | 11976.6 | 1.19 | 8.38 | 1.16 | 0.591 | 1.84 | 0.994 |
| 7 | 12461.5 | 1 | 387,237.3 | 31.1 | 478 | 12.1 | 8.69 | 12.8 | 29.6 |
| 9 | 12.6 | 1 | 144.0 | 11.4 | 6230 | 14 | 9.3 | 5.52 | 9.19 |
| 11 | 8413.2 | 1 | 245751.3 | 29.2 | 93.4 | 11 | 8.29 | 449 | 18.1 |
| 13 | - | - | 13.4 | 1 | - | - | 0.253 | - | 2.74 |
| 15 | - | - | 22.6 | 1 | 11.4 | 0.957 | 3.08 | 1.12 | 1.98 |
| 17 | 176.8 | 1 | 187.9 | 1.06 | 128 | 4.41 | 2.76 | 1.38 | 1.89 |
| 19 | - | - | 7.7 | 1 | - | - | 1.96 | 0.366 | 2.64 |
| 21 | - | - | 0.2 | 1 | - | - | 4.79 | - | - |
| 23 | - | - | 0.3 | 1 | - | - | 2.46 | 3.54 | 4.19 |
| 25 | - | - | 4.0 | 1 | - | - | 2.62 | 2.94 | 3.46 |
| 27 | - | - | 17.7 | 1 | - | - | 0.123 | 0.034 | 0.319 |
| 29 | - | - | 16.3 | 1 | - | - | 0.124 | 0.166 | 0.075 |
The kcat/Km of native TrSOX for substrate 1, 3, 5, 7, 9, 11, and 17 were set as 1; the kcat/Km of E251V for substrate 13, 15, 19, 21, 23, 25, 27 and 29 were set as 1.