Table 2.
Effect of selective protease inhibitors on the protease activity of GsProS8. Different letters (a-f) on the same column indicated significant (p < 0.05) differences among samples*
| Inhibitor | Concentration (mM) | Specific activity (U/mg) | Relative activity (%) |
|---|---|---|---|
| Pepstatin A | 0.01 | 3201.0 ± 49.7a | 89.9 |
| 0.02 | 2993.5 ± 52.0b | 84.1 | |
| PMSF | 1 | 162.3 ± 20.3e | 4.6 |
| 4 | 10.3 ± 2.3f | 0.3 | |
| Iodoacetamide | 1 | 3277.0 ± 15.8a | 92.1 |
| 4 | 2901.0 ± 36.2b | 81.5 | |
| EDTA | 1 | 2475.7 ± 29.4c | 69.5 |
| 4 | 2118.2 ± 6.8d | 59.5 |
*Enzymatic reaction was carried out using casein as a substrate at 50 °C in 0.05 mol/L MOPS buffer (pH 8.5). Specific activity was shown as mean ± SD (n = 3). Relative activity was expressed as a percentage of the activity in the absence of inhibitors (the control)