TABLE 2.
Demonstration of a dibasic endopeptidase activity in cell extracts of T. reesei
| Substrate | Presence (+) or absence (−) of 1 mM Ca2+ | pH | Mean activity ± SD (U/mg)a |
|---|---|---|---|
| Boc-LKR-MCA | − | 7.0 | 10.9 ± 0.6 |
| Boc-LKR-MCA | − | 5.5 | 15.6 ± 0.9 |
| Boc-LKR-MCA | + | 7.0 | 27.6 ± 1.4 |
| Boc-LKR-MCA | + | 5.5 | 31.9 ± 1.6 |
| Boc-LRR-MCA | − | 5.5 | 12.8 ± 0.8 |
| Boc-GKR-MCA | − | 5.5 | 10.7 ± 0.6 |
| Boc-VPR-MCA | − | 5.5 | 8.9 ± 0.5 |
a
Units are given in nanomoles of MCA released in 1 min per milligram (wet weight) of mycelia. The enzyme assay was performed as described in Materials and Methods. The numbers represent the means and standard deviations of four independent experiments. All data were obtained with the same mycelial suspension.