TABLE 4.
Kinetic parameters of the WT and its mutants toward 2-CN
| Mutants | Vmax (μmol/mg/min) (×10−3) |
Km (mM) | kcat (s−1) (×10−3) |
kcat/Km (s−1×mM−1) (×10−3) |
|---|---|---|---|---|
| Kinetic parameters of hydrolysis activity | ||||
| WT | 6.51 ± 0.31 | 3.15 ± 0.06 | 4.48 ± 0.21 | 1.42 ± 0.04 |
| N165C | 21.14 ± 0.87 | 2.47 ± 0.04 | 14.55 ± 0.60 | 5.89 ± 0.15 |
| N165A | 14.72 ± 0.27 | 2.58 ± 0.19 | 10.12 ± 0.19 | 3.94 ± 0.22 |
| N165G | 1.99 ± 0.06 | 2.55 ± 0.03 | 1.37 ± 0.04 | 0.54 ± 0.01 |
| W167A | 17.46 ± 1.12 | 8.89 ± 0.39 | 11.99 ± 0.76 | 1.35 ± 0.03 |
| W167G | 130.43 ± 2.63 | 6.78 ± 0.26 | 89.52 ± 1.81 | 13.21 ± 0.24 |
| Kinetic parameters of hydration activity | ||||
| WT | 37.67 ± 2.60 | 3.78 ± 0.09 | 25.93 ± 1.79 | 6.85 ± 0.31 |
| N165C | 16.56 ± 0.17 | 2.87 ± 0.05 | 11.39 ± 0.12 | 3.97 ± 0.03 |
| N165G | -a | - | - | - |
| W167A | - | - | - | - |
| W167G | - | - | - | - |
a
A dash indicates that the kinetic parameters were not calculated.