Table 4

Comparison of Clint between commercial enzyme sources and E. coli membranes expressing CYPs

Probe ReactionIsoformClint
Commercial SourceE. coli Membranes
μl · min−1 · nmol−1
Naproxen O-demethylationCYP2C94020
Diazepam N-demethylationCYP2C1960120
Dextromethorphan O-demethylationCYP2D6340200
  • Clint = Vmax/Km, calculated from the values in Table 3. Commercial sources of CYPs were B-lymphoblasts expressing CYP1A2, 2C9, 2D6, and 3A4, and baculosomes expressing CYP2C19.