ct8b00987_si_001.pdf (1.36 MB)
SPICA Force Field for Lipid Membranes: Domain Formation Induced by Cholesterol
journal contribution
posted on 2018-12-04, 00:00 authored by Sangjae Seo, Wataru ShinodaHeterogeneity
is essential for multicomponent lipid membranes. Especially, sterol-induced
domain formation in membranes has recently attracted attention because
of its biological importance. To investigate such membrane domains
at the molecular level, coarse-grained molecular dynamics (CG-MD)
simulations are a promising approach since they allow one to consider
the temporal and spatial scales involved in domain formation. In this
work, we present a new CG force field, named SPICA, which can accurately
predict domain formation within various lipids in membranes. The SPICA
force field was developed as an extension of a previous CG model,
known as SDK (Shinoda–DeVane–Klein), in which membrane
properties such as tension, elasticity, and structure are well reproduced.
By examining domain formation in a series of ternary lipid bilayers,
we observed a separation into liquid-ordered and liquid-disordered
phases fully consistent with experimental observations. Importantly,
it is shown that the SPICA force field can detect the different phase
behavior that results from subtle differences in the lipid composition
of the bilayer.