P450 | 3A4 | 3A5 | 3A4 | 3A5 | 3A4 | 3A5 | |||
---|---|---|---|---|---|---|---|---|---|
Cytochrome b5 | None | Added (1:3 ratio)a | Coexpressedb | ||||||
2-DCEI formation | 0.059 | 0.046 | 0.024 | 0.077 | 0.378 | 0.068 | |||
3-DCEI formation | 0.283 | 0.676 | 0.296 | 0.938 | 5.05 | 2.25 | |||
2- and 3-DCEI formation | 0.342 | 0.722 | 0.320 | 1.02 | 5.43 | 2.32 |
↵ a Molar ratio of P450 to cytochrome b5; cytochrome c reductase activity [nmol/(min × mg protein)] of 370 and 2200 for CYP3A4 and CYP3A5, respectively.
↵ b Coexpressed cytochrome c reductase activity [nmol/(min × mg protein)] at 5100 and 3900, and cytochrome b5 (pmol/mg protein) content at 1400 and 1600 for CYP3A4 and CYP3A5, respectively.