Coarse-grained models for lipid membranes

Lipid molecules are the major components of biomembranes, and various lipid molecules self-aggregate to form planar or spherical membranes. When lipid membranes are analyzed by molecular simulation, full-atomistic models or coarse-grained models are used.[1] Here we present some example models using the MARTINI coarse-grained model.[2]
Figure 1 shows a planar bilayer membrane composed of DPPC, a type of phospholipid, and cholesterol. The analysis of lipid membranes is focused on the structural characteristics such as thickness, density and mechanical properties.[3]

Lipid Nano Particles (LNPs) composed of lipids are used for drug delivery due to their high biocompatibility. Figure 2 shows a model of LNP of about 2 nm in diameter composed of DPPC, DOPC, and cholesterol, which can be easily modeled by J-OCTA and analyzed by MD calculations.

Figure 1. A Coarse-grained (MARTINI) model of lipid membranes composed of DPPC and CHOL.

Figure2. An LNP model composed of DPPC/DOPC/CHOL.

• References

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    S. Seo and W. Shinoda, J. Chem. Theor. Comp., 2019, 15, 762 (https://doi.org/10.1021/acs.jctc.8b00987)
  • S.J. Marrink, et al., J. Phys. Chem. B, 2007, 111, 7812 (https://doi.org/10.1021/jp071097f)
  • Y. Wang et al., BBA-Biomembranes, 2016, 1858, 2846 (https://doi.org/10.1016/j.bbamem.2016.08.005)