Apparent Km, Vmax, and intrinsic clearance values of the CYP1A2-mediated O-dealkylation of MAMC and the 4-substituted 7-methoxycoumarins
| Substrate | KmaxValue | VmaxValue | Vmax/Km |
|---|---|---|---|
| μM | min−1 | min−1/μM | |
| MAMC | 4.96 ± 0.85 | 0.45 ± 0.02 | 0.091 ± 0.019 |
| MMAMC | 2.12 ± 0.20 | 0.45 ± 0.01 | 0.212 ± 0.023 |
| EMAMC | 1.93 ± 0.23 | 1.15 ± 0.04 | 0.596 ± 0.089 |
| PMAMC | 1.48 ± 0.21 | 1.42 ± 0.05 | 0.959 ± 0.163 |
| BMAMC | 2.67 ± 0.03 | 3.98 ± 0.14 | 1.490 ± 0.067 |
| DiMMAMC | 1.57 ± 0.15 | 1.85 ± 0.05 | 1.178 ± 0.141 |
| MMPyrC | N.D. | N.D. | N.D. |
Human CYP1A2 was expressed in insect cells using baculovirus. Values are given as the mean ± S.D. (n = 3). MMPyrCO-dealkylation could not be detected.
N.D., not detected.