Percentages of low spin and high spin in CYP1A1 and CYP1A2 in the absence and the presence of phenacetin or acetaminophen at 27°C
| Enzyme (+Substrate) | Low Spin | High Spin |
|---|---|---|
| % | ||
| CYP1A1 (no substrate) | 95 | 5 |
| + Phenacetin | 93 | 7 |
| + Acetaminophen | 92 | 8 |
| CYP1A2 (no substrate) | 88 | 12 |
| + Phenacetin | 71 | 29 |
| + Acetaminophen | 79 | 21 |