TABLE 1

Concentrations of P450 substrates used in single point, IC50 shift, and kinact/KI experiments

Enzyme
Substrate
Protein Concentrationa
Single Point and IC50 Shift Experiments
kinact/KI Experiments
Incubation Time
[S]
Incubation Time
[S]
mg/ml min μM min μM
CYP1A2 Phenacetin 0.3 → 0.03 30 50 20 500
CYP2B6 Bupropion 0.5 → 0.05 20 80 12 800
CYP2C8 Amodiaquine 0.25 → 0.025 10 1.9 6 19
CYP2C9 Diclofenac 0.3 → 0.03 10 4 6 40
CYP2C19 S-Mephenytoin 2 → 0.2 40 60 30 600
CYP2D6 Dextromethorphan 0.3 → 0.03 10 5 6 50
CYP3A Midazolam 0.3 → 0.03 4 2.5 6 25
CYP3A
Testosterone
0.3 → 0.03
10
50
6
500

  • ↵ a Denotes protein concentrations used in the inactivation preincubations diluted into the activity incubations.