Table 5.
Effect of membrane incorporation of CYP2E1-BODIPY on the degree of its homooligomerization explored with homo-FRET*
| Membranous preparation | [CYP2E1]50%a, pmol/cm2 | (Lipid/CYP2E1)50% b | FRET Efficiency, % |
|---|---|---|---|
| SS(CPR) | 0.024 ± 0.005 | 14,400 ± 2,850 | 84 ± 10 |
| SS(3A4) | 2.0 ± 0.15 | 176 ± 14 | 74 ± 9 |
| SS(3A4)+ANF | 0.58 ± 0.06 | 604 ± 62 | 84 ± 20 |
The values given in the table were obtained by fitting the titration curves with the binary association equation (Eq. 2) in combination with equation defining the relationship between the relative increase in the intensity of fluorescence and the steady-state concentration of the homo-oligomers (Eq. 3). The “±” values show the confidence interval calculated for p = 0.05.
Surface density of P450 in the membranes at which the amplitude of the titration curves reaches 50% of the maximal level. This value is equal to the value of KD determined from the fitting of the titration curves with Eq. 2 combined with Eq. 3. The surface density was calculated from the RL/P ratio, as described in Materials and Methods using Eq. 1.
Lipid-to-P450 ratio at which the amplitude of the titration curves reaches 50% of the maximal level, which was calculated from the respective [CYP2E1]50% values.