FIGURE 6.

Biophysical characterization of lipoprotein particles containing WT apoE4 or apoE4[L28P]. Reconstituted discoidal lipoprotein particles consisting of WT or mutant apoE4, phosphatidylcholine, and cholesterol (PC/C-apoE4) were prepared as described under “Experimental Procedures.” A, far UV CD spectra of the protein component (WT or mutant apoE4) of PC/C-apoE4 particles. Spectra are averages of three separate experiments. The percentage of helical content was calculated on the basis of the molar ellipticity at 222 nm, as described under “Experimental Procedures.” *, p < 0.05 versus WT. B, thermal denaturation profiles of WT and mutant apoE4 in lipoprotein particles. The y axis has been normalized to correspond to the fraction of the protein in the unfolded state.