Interaction of enantiomeric alkylacyl and diacylglycerophosphocholines with cholesterol in bilayer membranes

✍ Scribed by A. Hermetter; F. Paltauf

• Publisher: Elsevier Science
• Year: 1982
• Tongue: English
• Weight: 355 KB
• Volume: 31
• Category: Article
• ISSN: 0009-3084
• DOI: 10.1016/0009-3084(82)90063-9

✦ Synopsis

The sn-I and sn-3 isomers of dioleoylglycerophosphocholine form vesicles of the same size as the racemic lipid. Identical permeability coefficients were found for the diffusion of glucose and chloride across bilayer membranes of vesicles consisting of these lipids. Vesicles made of mixtures of enantiomeric or racemic dioleoyllecithin with 30 reel% cholesterol have identical radii. Cholesterol reduces the permeability of bilayers for glucose and chloride irrespective of the steric configuration of the constituent phospholipid. Increasing concentrations of cholesterol (17, 33 and 50 mol%, respectively) broaden the (CH~) n signal in the IH-NMR..spectra (90 MHz) of unilamellar vesicles containing sn-l, sn-3 or rac alkyloleoylglycerophosphocholine to the same extent. These results indicate that the steric configuration of phospholipids has no gross effect on the arrangement of phospholipids and cholesterol in bilayer membranes.