Table 1.
Kinetic parameters for wild type and variants of BT3312
| Substrate | kcat/Kma | Relative activity | |
|---|---|---|---|
| Enzyme variant | |||
| Wild type | 1,6-β-Glucan (pustulan) | 1776 ± 20.6 | 1 |
| Wild type | 1,3-β-Glucan | 0 | 0 |
| Wild type | 1,4-β-Glucan | 0 | 0 |
| Wild type | 1,6-β-Galactan | 0 | 0 |
| E238A | 1,6-β-Glucan (pustulan) | 0 | 0 |
| H281A | 1,6-β-Glucan (pustulan) | 10 ± 1 | 0.006 |
| N282A | 1,6-β-Glucan (pustulan) | 17 ± 1 | 0.009 |
| D286A | 1,6-β-Glucan (pustulan) | 475 ± 30 | 0.27 |
| E339A | 1,6-β-Glucan (pustulan) | 0 | 0 |
| E339Q | 1,6-β-Glucan (pustulan) | 0 | 0 |
| W345A | 1,6-β-Glucan (pustulan) | 7 ± 1 | 0.004 |
| C393S | 1,6-β-Glucan (pustulan) | 9 ± 1 | 0.005 |
| C396S | 1,6-β-Glucan (pustulan) | 55 ± 3 | 0.03 |
| Oligosaccharides | |||
| Wild type | 1,6-β-Glucotriose | 1.7 × 106 ± 1.1 × 104 | |
| Wild type | 1,6-β-Glucotetraose | 2.6 × 106 ± 3.4 × 105 | |
| Wild type | 1,6-β-Glucohexaose | 6.0 × 106 ± 6.0 × 105 | |
| Wild type | 1,6-β-Glucooctaose | 6.4 × 106 ± 1.4 × 105 | |
a The kinetic parameter is mg ml−1 min−1 for pustulan and m−1 min−1 for glucooligosaccharides.