TABLE 2.
Catalytic parameters of wild-type PP, E367Q, C102A, and C102S for Cbz peptides and Ac amino acidsa
| Substrate | Wild-type PP
|
E367Q
|
C102A
|
C102S
|
||||
|---|---|---|---|---|---|---|---|---|
| Km (mM) | kcat (s−1) | Km (mM) | kcat (s−1) | Km (mM) | kcat (s−1) | Km (mM) | kcat (s−1) | |
| Cbz-F | 7.35 ± 1.40 | 91.4 ± 11.6 | ||||||
| Cbz-G-F | 4.51 ± 0.90 | 101 ± 6.6 | 5.16 ± 0.99 | 150 ± 9.2 | ND | <0.001 | 7.10 ± 1.10 | 0.0108 ± 0.0030 |
| Gcz-G-G-F | 3.10 ± 0.51 | 0.792 ± 0.19 | ||||||
| Ac-F | 5.20 ± 0.49 | 34.0 ± 4.2 | 6.64 ± 0.90 | 37.3 ± 5.1 | ND | <0.001 | 6.20 ± 1.90 | 0.0208 ± 0.0051 |
| Ac-M | 4.18 ± 0.53 | 45.6 ± 4.9 | ||||||
| G-F | 5.07 ± 0.99 | 103 ± 7.9 | ||||||
a
The hydrolytic reaction was measured at 85°C in 50 mM sodium phosphate buffer (pH 7.5) containing 5% DMF, and the substrate that hydrolyzed was less than 10% of the total substrate. The parameters for Ac-F and Ac-M were measured using less than 12 mM substrate. Values are means ± standard deviations for five determinations. ND, not determined.