Table 4 Kinetic parameters of CTendo45 and its mutants against CMC-Na and β-d-glucan
Substrate | Enzyme | Km (mg/mL) | Vmax (µg/min/mL) | kcat (s−1) | kcat/Km (µL/s/mg) |
|---|---|---|---|---|---|
CMC-Na | CTendo45 | 5.93 ± 0.54 | 4.42 ± 0.15 | 0.37 ± 0.04 | 62.06 ± 1.25 |
L47T | 3.28 ± 0.12 | 3.77 ± 0.03 | 0.25 ± 0.03 | 74.65 ± 1.36 | |
Q56T | 2.23 ± 0.41 | 3.89 ± 0.42 | 0.16 ± 0.03 | 70.67 ± 1.74 | |
G63T | 20.90 ± 1.27 | 9.84 ± 0.80 | 0.75 ± 0.05 | 35.68 ± 0.97 | |
R67S | 4.75 ± 0.20 | 8.21 ± 1.03 | 0.40 ± 0.08 | 83.49 ± 1.25 | |
T90A | 10.81 ± 0.05 | 15.87 ± 0.05 | 1.05 ± 0.12 | 97.54 ± 2.13 | |
R67S/T90A | 13.73 ± 0.06 | 18.66 ± 0.09 | 1.55 ± 0.07 | 112.9 ± 3.72 | |
β-d-glucan | CTendo45 | 29.11 ± 3.68 | 45.95 ± 5.68 | 4.03 ± 0.51 | 138.46 ± 2.07 |
L47T | 6.28 ± 0.94 | 14.50 ± 1.19 | 1.21 ± 0.14 | 192.43 ± 1.85 | |
Q56T | 16.68 ± 1.89 | 38.68 ± 4.06 | 2.96 ± 0.18 | 177.29 ± 1.47 | |
G63T | 56.57 ± 8.82 | 112.45 ± 16.10 | 7.94 ± 0.59 | 140.39 ± 1.64 | |
R67S | 17.03 ± 1.75 | 44.07 ± 5.21 | 3.38 ± 0.42 | 198.76 ± 2.17 | |
T90A | 28.34 ± 2.73 | 66.58 ± 5.40 | 6.18 ± 0.75 | 217.90 ± 2.83 | |
R67S/T90A | 57.73 ± 4.59 | 67.4 ± 2.87 | 13.95 ± 2.40 | 241.63 ± 18.69 |