MAGIC-ANGLE-SPINNING C-13-NMR SPIN-LATTICE RELAXATION STUDY OF THE LOCATION AND EFFECTS OF ALPHA-TOCOPHEROL, UBIQUINONE-10 AND UBIQUINOL-10 IN UNSONICATED MODEL MEMBRANES

Alpha-Tocopherol, ubiquinone-10 and ubiquinol-10 have been studied by high resolution magic angle samples spinning C-13-nuclear magnetic resonance in egg yolk phosphatidylcholine multilamellar vesicles model membranes in order to assess their location and the induced perturbations on this model system. Alpha-Tocopherol is placed in such a position that it is in close contact with the head group of the phospholipid and exposed to the solvent. In this position it significantly perturbs the phospholipid head group, the 5a-CH3 and the 7a-CH3 groups being the closest parts to the membrane surface. On the other hand, ubiquinol-10 perturbs the membrane surface more than ubiquinone-10, but neither compound significantly changed the phospholipid head group conformation.