Kinetic parameters of phenacetin hydrolase activities by recombinant AADAC and tissue microsomes
Data represent the mean ± S.D. of triplicate determinations. CLint values of human AADAC, HLM, HJM, HRM, mouse AADAC, and MPM are expressed as Vmax/Km.
| Species | Km | Vmax | CLint |
|---|---|---|---|
| nM | |||
| Human | |||
| AADAC | 1.8 ± 0.1 | 6.4 ± 0.2a | 3.5 ± 0.1b |
| Liver | 3.3 ± 0.2 | 3.6 ± 0.2c | 1.1 ± 0.0d |
| Jejunum | 2.5 ± 0.1 | 10.0 ± 0.0c | 4.0 ± 0.1d |
| Kidney | 2.3 ± 0.2 | 0.4 ± 0.0c | 0.2 ± 0.1d |
| Lung | 7.4 ± 0.4 | 0.8 ± 0.0c | 0.4 ± 0.0d,e |
| Rat | |||
| AADAC | 5.8 ± 0.1 | 12.6 ± 0.1a | 2.2 ± 0.0b,e |
| Liver | 29.8 ± 2.1 | 5.9 ± 0.4c | 0.2 ± 0.0d,e |
| Jejunum | 4.6 ± 0.2 | 0.3 ± 0.0c | 0.1 ± 0.0d,e |
| Kidney | 9.3 ± 0.4 | 0.6 ± 0.0c | 0.1 ± 0.0d,e |
| Lung | 5.3 ± 1.4 | 0.1 ± 0.0c | 0.1 ± 0.0d,e |
| Mouse | |||
| AADAC | 1.6 ± 0.1 | 9.2 ± 0.1a | 5.7 ± 0.3b |
| Liver | 9.8 ± 0.2 | 17.1 ± 0.4c | 1.3 ± 0.1d,e |
| Jejunum | 11.2 ± 2.1 | 1.4 ± 0.3c | 0.1 ± 0.0d,e |
| Kidney | 7.1 ± 0.1 | 2.9 ± 0.2c | 0.4 ± 0.1d,e |
| Lung | 2.9 ± 0.4 | 0.1 ± 0.0c | 0.0 ± 0.0d |
↵a Vmax for AADAC is measured in nmol · min−1 · unit−1.
↵b CLint for AADAC is measured in μl · min−1 · unit−1.
↵c Vmax for liver, jejunum, kidney, and lungs is measured in nmol · min−1 · mg−1.
↵d CLint for liver, jejunum, kidney, and lung is measured in μl · min−1 · mg−1.
↵e If the Km value was relatively high, the CLint value was calculated with initial slope of the velocity versus substrate concentration.