Table 2. Kinetic Parameters for Sialidase-Catalyzed Cleavage of 7-Fluorosialosides vs Parent.
| enzyme | substrate | no. | Km (mM) | kcat (min–1) | kcat/Km (min–1 mM–1) | kcat/Km (relative to 7F substrate) |
|---|---|---|---|---|---|---|
| T. rangeli TrSA (GH33) | 7OH | 10 | 2.4 (±0.2) | 83 (±4) | 34 (±4) | 254 |
| 7F | 11 | not determined | not determined | 0.13 (±0.01) | 1 | |
| C. perfringens NanI (GH33) | 7OH | 10 | 0.80 (±0.04) | 78 (±2) | 97 (±7) | 133 |
| 7F | 11 | not determined | not determined | 0.73 (±0.03) | 1 | |
| M. viridifaciens NedA (GH33) | 7OH | 12 | 0.17 (±0.01) | 940 (±90) | 5500 (±900) | 41 |
| 7F | 13 | 1.2 (±0.15) | 170 (±50) | 135 (±60) | 1 | |
| hNEU2 (GH33) | 7OH | 12 | 3.5 (±0.3) | 3.0 (±0.1) | 0.9 (±0.1) | – |
| 7F | 13 | no activity detected | – | |||
| enzyme | substrate | no. | Km (mM) | Vmax rela (μM min–1) | Vmax/Km rela (min–1 × 10–3) | kcat/Km (relative to 7F substrate) |
|---|---|---|---|---|---|---|
| influenza N9 (GH34) | 7OH | 10 | 0.83 (±0.06) | 17.5 (±0.5) | 21 (±2.0) | 1.8 |
| 7F | 11 | 0.39 (±0.04) | 4.6 (±0.2) | 12 (±1.6) | 1 |
a
Values determined from a fixed volume of enzyme preparation.