Nanomembrane is a very important part of living systems. Alive cells have lipid bilayer nanomembrane in liquid phase. The lateral pressure profile, or stress profile, across a cell nanomembrane is the result of the inhomogeneous nature of the interactions within a nanomembrane. It has been shown that the work exerted by the pressure profile when a protein conformational change takes place is significant, of the order of 10kBT, and that the lateral pressure profile averaged over the whole nanomembrane is modified by the inclusion of a protein. Indeed, understanding the full coupling for stress arising from protein-lipid interactions is of profound importance and calls for elucidation. Here proper ensembles for molecular dynamics simulation of inhomogeneous nanoscale system of nanomembrane-cytotoxin protein are introduced. The Virial pressure theorem together with using molecular dynamics simulation data are proposed to use to calculate pressure filed. The predicted pressure tensor of system without cytotoxin is compared with that of system including this protein. Finally deformation of nanomembrane is related to the variation of pressure tensor.
3F1010 Structure and lateral pressure profile of lipid bilayer containing gramicidin A by molecular dynamics simulation(Membrane Proteins,Oral Presentation)