Acidic inactivation of outside exposed PM CYP2D6
| Type of membranes | Dextromethorphan conversion | CPR activity3-b | |
|---|---|---|---|
| Per mg of protein | Per unit of CPR3-a | ||
| % | μmol/min/mg of proteins | ||
| PM | 5 ± 1 | 11 ± 2 | 1.2 ± 0.1 |
| Acidic PM | 1.6 ± 0.5 | 4 ± 2 | 1.2 ± 0.2 |
| Microsomes | 11 ± 1 | 6 ± 2 | 5.0 ± 0.3 |
| Acidic microsomes | 9.8 ± 0.9 | 7 ± 2 | 4.5 ± 0.5 |
Freshly prepared spheroplasts were incubated for 2 min on ice, in ammonium acetate buffer, pH 3, (sample) or 6.3 (control). pH was shifted to 6.3 and material was divided into two parts. One part was attached on the silica microbeads for PM preparations. The other part was used to prepare microsomes. Values are the mean ± standard deviation (two duplicates on three independent cultures).