Abstract
Binding of plasma apolipoproteins to surface membrane of lipid particles causes the strong positive curvature stain. Although apolipoproteins can hardly bind to egg phosphatidylcholine planar surface in bilayers, many apolipoproteins bind to the emulsion surface with significantly higher capacity compared to bilayers. This marked difference in apolipoprotein binding between bilayers and emulsions can be explained by the difference in mechanisms by which the apolipoprotein-induced membrane curvature stress is relaxed. The binding capacity of apolipoprotein A-I increases with increasing spontaneous negative curvature in bilayers, whereas in emulsions, the contribution of core lipids to the relief of curvature stress appears to be the key event for apolipoprotein binding.
