A 13C NMR method for determination of the transbilayer distribution of phosphatidylcholine in large, unilamellar, protein-free and protein-containing vesicles.
(1) Large unilamellar vesicles have been prepared from N-[Ne3-13C]-18 : 1c/18 : 1c-phosphatidylcholine, both with and without the major intrinsic proteins from the human erythrocyte membrane incorporated in the bilayer. (2) It is shown that the inside-outside distribution of the lipid molecules in these large unilamellar structures can be determined using 13C NMR. (3) Large vesicles of 18 : 1c/18 : 1c-phosphatidylcholine containing glycophorin show an enhanced permeability to Dy3+. It is shown that the permeability barrier of these vesicles can be restored by addition of 10 mol% 18 : 1c/18 : 1c-phosphatidylethanolamine or 1-18 : 1c-lysophosphatidylcholine.
D000818:Animals; D004910:Erythrocyte Membrane / Q000032:analysis*; D004912:Erythrocytes / Q000032:analysis*; D005614:Freeze Fracturing; D006021:Glycophorins; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008565:Membrane Proteins / Q000097:blood*; D008567:Membranes, Artificial; D008968:Molecular Conformation; D010713:Phosphatidylcholines; D011487:Protein Conformation
D006021:Glycophorins; D008565:Membrane Proteins; D008567:Membranes, Artificial; D010713:Phosphatidylcholines