Table 2.
Characteristic | Inhibitors | Concentration | Remaining activity (%) |
---|---|---|---|
Serine protease inhibitor | Leupeptin | 10 mM | 100.7 |
SBTI | 0.4 mg/ml | 100.9 | |
TLCK | 10 mM | 99.4 | |
TPCK | 10 mM | 99.9 | |
PMSF | 1 mM | 89.2 | |
10 mM | 1.0 | ||
Metalloprotease inhibitor | EDTA | 0.5 mM | 78.1 |
1 mM | 64.2 | ||
5 mM | 1.4 | ||
Imidazole | 0.5 M | 82.4 | |
L-Histidine | 0.5 M | 108.1 | |
Cysteine protease inhibitor | IAA | 0.1 M | 98.0 |
NEM | 0.1 M | 114.2 | |
E64 | 1 mM | 99.2 | |
Aspartic protease inhibitor | Pepstatin A | 1 mM | 102.1 |
Amino peptidase inhibitor | Bestatin | 2 mM | 102.6 |
Denaturants | Substances | Concentration | Remaining activity (%) |
H-bond breaker | Urea | 1M | 20.8 |
2M | 0.0 | ||
Detergent | SDS | 0.5% | 0.0 |
1.0% | 0.0 | ||
Reducing agents | DTT | 1 mM | 38.5 |
10 mM | 2.3 | ||
20 mM | 0.1 | ||
BME | 1 mM | 64.7 | |
10 mM | 41.9 | ||
20 mM | 14.1 |
a The enzymatic activity was determined at pH 9.5 and 55°C in the presence of 5 mg/ml substrate and 5 mM CaCl2. The experiment was performed in triplicate, and standard errors from the means were within 15% of the reported values.