Table 7.
Effects of Various Protease Inhibitors on SAS-1 and SAS-2 Hydrolytic Activity
Percent Activity of Noninhibited
|
|||
---|---|---|---|
Inhibitor | Preferred Protease Target | SAS-1 | SAS-2 |
No inhibitor | - | 100% ± 2.2% | 100% ± 3.0% |
Z-GF-NHO-Bza | Subtilisin | 1% ± 0.5% | 1% ± 2.2% |
Boc-APF-NHO-Bza | Subtilisin | 93% ± 4.2% | 92% ± 3.8% |
Aprotinin | Ser | 73% ± 8.1% | 77% ± 2.8% |
AEBSFb | Ser | 64% ± 5.4% | 73% ± 4.2% |
PMSFc | Ser | 60% ± 5.9% | 70% ± 3.4% |
Leupeptin | Ser and Cys | 88% ± 2.5% | 81% ± 2.5% |
Antipain | Ser and Cys | 100% ± 3.9% | 100% ± 2.7% |
E-64d | Cys | 79% ± 5.1% | 81% ± 3.2% |
PCMBe | Thiol | 89% ± 4.0% | 100% ± 1.9% |
Pepstatin A | Aspartate | 91% ± 2.5% | 89% ± 4.1% |
Purified SAS-1 and SAS-2 were preincubated with 200 μM inhibitor for 2 h, except PMSF (1 mM) and aprotinin (1 μg/mL), and then assayed for Z-VAD-AFC hydrolytic activity for 1 h.
Recognition sequence in single-letter amino acid code. NHO, nitrosyl; Bz, benzoyl.
4-(2-aminoethyl)-benzenesulfonyl-fluoride.
Phenylmethylsulfonyl fluoride.
Trans-epoxysuccinyl-l-leucylamido-(4-guanidino)-butane.
p-Chloromercuribenzoic acid.