TABLE 1.
Specific activities and kinetics of wild-type XynAS9 and its mutants with birchwood xylan as the substrate
| Enzyme | Sp act (U/mg)a | Km (mg/ml)a | kcat (/s)a | kcat/Km (ml/s · mg) | Vmax (U/mg)a |
|---|---|---|---|---|---|
| XynAS9 | 630.3 ± 12.5 | 1.03 ± 0.21 | 790.2 ± 14.3 | 760.3 | 950.8 ± 23.12 |
| V81P mutant | 155.2 ± 2.1 | 3.19 ± 0.91 | 218.4 ± 3.8 | 68.2 | 268.4 ± 8.52 |
| G82E mutant | 78.5 ± 1.4 | 0.60 ± 0.01 | 75.7 ± 3.1 | 121.4 | 90.3 ± 3.14 |
| V81P/G82E mutant | 206.9 ± 9.6 | 1.05 ± 0.15 | 212.5 ± 7.4 | 202.5 | 255.6 ± 8.33 |
| D185P/S186E mutant | 90.7 ± 3.4 | 4.02 ± 1.32 | 184.4 ± 6.4 | 45.8 | 221.9 ± 7.30 |
| V81P/G82E/D185P/S186E mutant | 160.4 ± 5.3 | 2.21 ± 0.79 | 235.6 ± 6.8 | 106.5 | 283.5 ± 7.97 |
a
Values are means ± standard deviations.