Table 2 Comparison of the enzymatic properties of the wild-type and the single point mutants

K_m (µmol/L)

1.24 ± 0.03

0.61 ± 0.01

0.59 ± 0.02

1.52 ± 0.11

k_cat (S^− 1)

2.29 ± 0.20

1.14 ± 0.22

1.11 ± 0.03

3.75 ± 0.34

K_d (k_cat/K_m)

1.65

1.87

1.88

2.5

Specific activity (U/mg)

868.68

608.35

598.52

367.17

half-life (min)

28.7 ± 0.73

59.5 ± 0.32

82 ± 0.57

11.5 ± 0.35

Optimal pH

8

8

8

8

Optimum temperature

55℃

55℃

55℃

55℃