Liquid diffraction analysis of the model membrane system. Egg lecithin + myelin protein (N-2)

The scattering from the model membrane system, egg lecithin + myelin protein (N-2), has been analyzed by liquid diffraction methods. It is found that by manipulating the protein-lipid ratio, the scattering domains of the protein and lipid can be identified. The multilayer contribution can also be identified by its position and concentration behavior in both the intensity pattern and its Fourier transform. When the multilayer and protein components are subtracted, the phospholipid scattering and an interaction term are left: these two can be resolved by a reasonable assessment of their relative magnitude in the boundary region where they overlap. The interaction term can then be used to determine the most probably position of the protein in the membrane. The deconvoluted protein and lipid transforms can then be combined in the proper way to obtain the electron density profiles. The resolution of the interaction term is not yet complete, but a method for accomplishing this is discussed.