Abstract
The intermolecular interactions and microscopic miscibility in the lipid bilayers of single component and binary mixtures were investigated using solid-state NMR. The glycerol backbones of phosphatidylethanolamine (PE), phosphatidylcholine (PC), cardiolipin (CL) and phosphtidylglycerol (PG) were specifically dueterated. The results of 2H-NMR and 31P-NMR analyses have shown that PE is completely miscible with CL and PG, while PC is not. The latter was suggested to form microdomains in the lipid bilayer. This was explained by the ability of hydrogen-bond-network formation of their polar head groups. The microdomain formation also regulates the interaction between lipid bilayers and c-type cytochromes. The biological significances of this nature of phospholipids are discussed.
