(749f) Modeling Domain Formation and Protein Adsorption in Model Lipid Bilayers

Uline, M. J. - Presenter, Northwestern University
Szleifer, I. - Presenter, Northwestern University

Using a three-dimensional molecular theory for lipids that uses all of the physical conformations of the lipids along with the attractive and electrostatic interactions, the thermodynamics and kinetics of ordered domain formation in lipid bilayers is studied in various biological relevant environments. The theory captures the shape of experimental phase diagrams of model lipid bilayers of a high melting point saturated lipid, a low melting point unsaturated lipid and cholesterol. Using the theoretically determined phase diagram, the partition coefficients of protein chain anchors into liquid-ordered and liquid-disordered phases is calculated as a function of temperature and degree of saturation of the chain anchor. Extending on this work, we can now take into account the exact molecular architecture of protein chain anchors and calculate the orientations and positions of proteins as they arrange themselves at the order-disorder phase boundary.