Detection, Interaction, And Mechanism Of Leu-enkephalin And Copoly(Lys/Tyr) Transportation Across Lipid Bilayer Membranes

Chapter â… Investigation of Interaction of Leu-enkephalin with Lipid MembranesBACKGROUNDEnkephalins(Leu-enkephalin or Met-enkephalin) are termed endogenous morphine-like substances. They are implicated in a wide variety of physiological processes. Previous studies have suggested that opioid peptides demonstrated their biological effects by reacting with their membrane-embedded receptor proteins containing potential sites of association with lipids. Although many studies have been carried out on the interaction of enkephalins and lipid membranes, most of them were focused on the conformation feature of enkephalins upon their binding to receptors or lipid membranes. In the present study, we tested the mechanism and efficiency of translocation of leu-enkephalin and leu-enkephalinamide across phospholipid membrane.METHODSZeta potential method (ZT) was applied to detect the association of leu-enkephalin and leu-enkephalinamide on phospholipid membranes constituted from soybean phospholipids, egg-phosphatidylcholine, dioleoyl-phosphatidylethanolamine, cholesterol, and sphingomyelin. Translocation of the peptides over lipid membranes was examined by...