506 Molecular Dynamics Study of Lipid Bilayers in Shear Flow

Nonequilibrium molecular dynamics simulations are performed on lipid bilayer membranes with ambient water under shear flow along the bilayer plane to investigate conformational change of lipid molecules. In the case of a shear rate of 12.9ns^<-1>, the velocity gradient in the lipid bilayer region is extremely small, while that in water layer is much larger. In spite of the small velocity gradient, configurations and conformations of the lipid membrane are clearly changed as compared to those in an equilibrium state. The lipid bilayer is distorted and lipid molecules are tilted by approximately 30 degrees from the normal of the bilayer plane toward the flow direction, and randomness of hydrocarbon chains of lipid molecules was increased.