TABLE 2

Kinetic parameters for phenacetin O-deethylation by recombinant CYP1As and CYP2As

Data are mean ± S.D. of three independent experiments.




Km

Vmax

Vmax/Km
μM pmol/min/pmol P450 nl/min/pmol P450
CYP1A1 56.2 ± 2.3 1.5 ± 0.1 26.8 ± 2.7
CYP1A2 29.2 ± 0.4 1.9 ± 0.1 66.4 ± 4.2
CYP2A6 N.A. N.A. N.A.
CYP2A13
21.8 ± 2.4a,b
2.9 ± 0.3a,b
133.2 ± 17.6a,c
  • N.A., not applicable.

  • a P < 0.005 compared with CYP1A1.

  • b P < 0.05 and c P < 0.005 compared with CYP1A2.