Table 5.
Kinetic parameters for the hydrolysis of NPPC by the S. pneumoniae H90A Pce mutant at different pH values
| pHa | Km (mM) | kcat (s−1) | kcat/Km (mM−1 s−1) |
| 6.0b | 1.1 ± 0.1 | 0.43 ± 0.02 | 0.38 ± 0.2 |
| 7.0c | 1.7 ± 0.4 | 1.13 ± 0.07 | 0.7 ± 0.1 |
| 7.6b | 2.6 ± 0.3 | 1.47 ± 0.04 | 0.56 ± 0.05 |
| 8.0d | 1.0 ± 0.1 | 2.84 ± 0.07 | 2.8 ± 0.2 |
| 8.25d | 0.75 ± 0.06 | 2.95 ± 0.06 | 3.9 ± 0.2 |
| 9.0b | 1.8 ± 0.3 | 4.5 ± 0.2 | 2.5 ± 0.3 |
| 10.0b | 3.9 ± 0.8 | 4.7 ± 0.4 | 1.2 ± 0.1 |
aMeasurements were made at 25°C in Bis-Tris-propane,b HEPES,c and HEPBSd at 3 μM Zn2+ (I = 0.05).