Influence of adhesion-promoting glycolipids on the structure and stability of solid-supported lipid double-bilayers

Abstract

Glycolipids have a considerable influence on the interaction between adjacent biomembranes and can promote membrane adhesion trough favorable sugar–sugar “bonds” even at low glycolipid fractions. Here, in order to obtain structural insights into this phenomenon, we utilize neutron reflectometry in combination with a floating lipid bilayer architecture that brings two glycolipid-loaded lipid bilayers to close proximity. We find that selected glycolipids with di-, or oligosaccharide headgroups affect the inter-bilayer water layer thickness and appear to contribute to the stability of the double-bilayer architecture by promoting adhesion of adjacent bilayers even against induced electrostatic repulsion. However, we do not observe any redistribution of glycolipids that would maximize the density of sugar–sugar contacts. Our results point towards possible strategies for the investigation of interactions between cell surfaces involving specific protein–protein, lipid–lipid, or protein–lipid binding.