TABLE 3.
Effect of pAPMSF and PMSF on the T. reesei dibasic endopeptidase activity in vitro and in vivo
| Substrate | Presence (+) or absence (−) of:
|
Condition | Mean activity ± SD (U/mg)a | |
|---|---|---|---|---|
| pAPMSF | PMSF | |||
| Boc-LKR-MCA | − | − | In vitro | 100 ± 6.2 |
| + | − | In vitro | 12.9 ± 5.1 | |
| − | + | In vitro | 100 ± 6.3 | |
| − | − | In vivo | 100 ± 5.9 | |
| + | − | In vivo | 19.4 ± 2.9 | |
| − | + | In vivo | 100 ± 5.8 | |
| Boc-LRR-MCA | − | − | In vitro | 81.7 ± 5.7 |
| + | − | In vitro | 8.6 ± 3.4 | |
| − | + | In vitro | 82.6 ± 6.8 | |
| Boc-GKR-MCA | − | − | In vitro | 72.0 ± 6.0 |
| + | − | In vitro | 6.9 ± 1.9 | |
| − | + | In vitro | 71.4 ± 4.0 | |
a
Values are given as the percentage of activity with Boc-LKR-MCA in the absence of any inhibitor. Cell extracts (in vitro) or mycelia were incubated with the inhibitors (1 mM pAPMSF or 5 mM PMSF, final concentration, respectively) for 1 h. The mycelia were then used to prepare the cell extracts (in vivo). The numbers indicate the means and standard deviations of four independent experiments. All data were obtained with the same mycelial suspension.