Kinetic parameters for the alkaline phosphatase-catalyzed hydrolysis of various phosphate prodrugs
| Preps | Km | Vmax | Vmax | Vmax/Km | Vmax/Km | Protein Concentrationa |
|---|---|---|---|---|---|---|
| µM | nmol/min per nanogram of protein | µmol/min per IU | µl/min per nanogram | ml/min per IU | ||
| Fosphenytoin | ||||||
| Monkey-rIALP | 768.0 ± 221.9 | 2.69 ± 0.40 | 8.88 | 3.50 | 11.55 | 0.4 ng/ml, 74 × 10–6 IU/ml |
| Rat-rIALP | 25.8 ± 9.1 | 1.56 ± 0.12 | 8.48 | 60.40 | 328.44 | 0.4 ng/ml, 121.2 × 10–6 IU/ml |
| RIMS | 23.1 ± 3.1 | 0.002 ± 0.00 | Biphasic 5.40 | 500 ng/ml, 185 × 10–6 IU/ml | ||
| Clindamycin Phosphate | ||||||
| Monkey-rIALP | 86.4 ± 11.6 | 0.08 ± 0.002 | 0.264 | 0.92 | 3.036 | 12.5 ng/ml, 2300 × 10–6 IU/ml |
| Rat-rIALP | 460.8 ± 52.5 | 0.16 ± 0.005 | 0.870 | 0.34 | 1.849 | 12.5 ng/ml, 3787 × 10–6 IU/ml |
| RIMS | 5.2 ± 18.8 | 0.001 ± 0.004 | Biphasic 2.70 | 2703 ng/ml, 1000 × 10–6 IU/ml |
a Incubation time: 10 minutes