Table 2.
High-temperature cellulases are inactive at room temperature
| Substrate and cellulasea | Activity (mU)b | Optimum temp (°C) | % Retaining activity at temp (°C): |
||
|---|---|---|---|---|---|
| 60 | 45 | 20 | |||
| PASC | |||||
| TCel1 | 44.03 | 102 | 56.0 | 40.0 | 20.0 |
| TCel2 | 5.62 | 96.0 | 53.6 | 34.1 | 14.6 |
| TCel3 | 33.68 | 98.0 | 42.2 | 25.3 | 14.1 |
| TCel4 | 4.72 | 85.0 | 71.4 | 46.4 | 14.3 |
| TCel5 | 23.68 | 94.0 | 44.7 | 21.1 | 10.5 |
| TCel6 | 14.31 | 95.0 | 26.0 | 11.6 | 4.3 |
| pNPG | |||||
| TCel11 | 69.4 | 98.0 | 4.4 | 1.1 | 1.0 |
| TCel12 | 60.9 | 92.0 | 25.0 | 12.5 | 2.5 |
a
PASC, phosphoric acid-swollen Avicel; pNPG, p-nitrophenylglycoside.
b
Cellulase specific activity, μM reducing glucose/min/mg protein at 85°C and pH 6; beta-glucosidase specific activity, μM pNP/min/mg protein at 85°C and pH 6.