Atomistic and Coarse-Grained Computer Simulations of Raft-Like Lipid Mixtures
互联网
578
Computer modeling can provide insights into the existence, structure, size, and thermodynamic stability of localized raft-like
regions in membranes. However, the challenges in the construction and simulation of accurate models of heterogeneous membranes
are great. The primary obstacle in modeling the lateral organization within a membrane is the relatively slow lateral diffusion
rate for lipid molecules. Microsecond or longer time-scales are needed to fully model the formation and stability of a raft
in a membra ne. Atomistic simulations currently are not able to reach this scale, but they do provide quantitative information
on the intermolecular forces and correlations that are involved in lateral organization. In this chapter, the steps needed
to carry out and analyze atomistic simulations of hydrated lipid bilayers having heterogeneous composition are outlined. It
is then shown how the data from a molecular dynamics simulation can be used to construct a coarse-grained model for the heterogeneous
bilayer that can predict the lateral organization and stability of rafts at up to millisecond time-scales.