FIGURE 6.

The ³¹P NMR spectra of oriented bilayer samples of both POPC and POPS bilayers in the absence (A and C) and in the presence (B–F) of 2 mol % Sap C with respect to the lipids at 25°C. (B) Sap C was dissolved in a minimal amount of TFE and mixed with the lipids dissolved in chloroform. After application onto the glass plates and drying of the protein-lipid complex overnight, a neutral buffer (pH 7.0) was added at the top of the dried bilayers before stacking of the glass plates. Sample D was prepared exactly the same as sample B except that POPS was used instead of POPC phospholipids. (E) POPS alone was spotted (on the glass plates) and dried. Then the protein dissolved in a neutral buffer (pH 7.0) was added at the top of the dried phospholipids before stacking. Sample F was prepared exactly the same as samples B and D except that methanol was used to initially dissolve Sap C instead of TFE. All spectra were conducted with the bilayer normal of the sample aligned parallel to the static magnetic field.