omega-6 and omega-3 fatty acids: monolayer packing and effects on bilayer permeability and cholesterol exchange.

Abstract

It has been suggested that the polyunsaturated omega-3 fatty acid, docosahexaenoic acid (DHA), can adopt unique closely packed arrays in lipid bilayers (Glomset and Applegate. (1986) J. Lipid Res. 27, 658-680). These conformations are predicted on the basis of molecular dynamics calculations and are in contrast to the expanded conformations characteristic of omega-6 unsaturated fatty acids. It has also been suggested that close packing of omega-3 acyl chains could have a substantial affect on the physical properties of lipid bilayers (e.g. permeability). We report here some experimental tests of these predictions. Surface pressure-area experiments have been carried out on DHA and its mixture..