P450 Enzymes | Km | Vmax | Vmax/Km |
---|---|---|---|
mM | nmol/min/nmol P450 | ml/min/nmol P450 | |
CYP1A2 | 0.36 ± 0.04 | 3.58 ± 0.11 | 9.9 |
CYP2A6 | 1.10 ± 0.26 | 6.77 ± 0.78 | 6.2 |
Kinetic analyses for 5-FU formation from tegafur were determined at a P450 concentration of 0.020 μM (Supersomes, Gentest) and substrate concentrations between 25 μM and 2 mM. The kinetic parameters were calculated from the fitted curves using the computer program KaleidaGraph.