Kinetic parameters for chlorzoxazone 6-hydroxylase activity and 7-ethoxycoumarin O-deethylase activity by recombinant CYP2E1 in single or coexpression systems with PGRMC1
The expression systems were constructed using recombinant adenoviruses as described under Materials and Methods. Kinetic parameters are calculated from curves by nonlinear regression. Data are mean ± S.D. of three independent experiments.
| AdCYP2E1 + AdPGRMC1 | Chlorzoxazone 6-Hydroxylation | 7-Ethoxycoumarin O-Deethylation | ||||
|---|---|---|---|---|---|---|
| Km | Vmax | Vmax/Km | Km | Vmax | Vmax/Km | |
| μM | pmol · min−1 · pmol P450−1 | μl · min−1 · pmol P450−1 | μM | pmol · min−1 · pmol P450−1 | μl · min−1 · pmol P450−1 | |
| 67.1 ± 5.6 | 618.3 ± 18.2 | 9.3 ± 0.5 | 40.2 ± 2.5 | 16.0 ± 1.2 | 0.40 ± 0.01 | |
| ×1 | 85.5 ± 21.6 | 667.8 ± 112.7 | 8.0 ± 0.8 | 38.3 ± 0.6 | 13.6 ± 0.4 | 0.35 ± 0.02* |
| ×2 | 56.1 ± 8.2 | 617.9 ± 56.1 | 11.1 ± 0.6 | 38.3 ± 0.8 | 13.6 ± 0.7 | 0.36 ± 0.01* |
| ×4 | 65.6 ± 7.2 | 723.1 ± 52.6 | 11.1 ± 1.0 | 42.6 ± 1.5 | 16.0 ± 0.4 | 0.38 ± 0.02* |
↵* P < 0.05 compared with control by Shirley-Williams' test.