Development of a coarse-grained lipid model, LIME 2.0, for DSPE using multistate iterative Boltzmann inversion and...

Area of Science:

• Biophysics
• Computational Chemistry
• Materials Science

Background:

• Lipid bilayers are crucial for cell membranes.
• Accurate simulation of lipid behavior is computationally intensive.
• Previous models like LIME used single square wells for coarse-grained simulations.

Purpose of the Study:

• To introduce LIME 2.0, an enhanced implicit solvent model for lipids.
• To improve the accuracy of intermolecular interactions in coarse-grained simulations.
• To enable multi-temperature simulations of lipid bilayers with a single parameter set.

Main Methods:

• Developed LIME 2.0 with multiple square wells for intermolecular interactions.
• Employed the multi-state iterative Boltzmann inversion (MS-IBI) scheme for parameterization.
• Performed coarse-grained (CG) simulations of DSPE lipid bilayers.

Main Results:

• LIME 2.0 accurately reproduces atomistic simulation results for lipid bilayers.
• The model successfully predicts the phase transition temperature of lipid bilayers.
• Observed lipid translocation ('flip-flop') phenomenon in CG simulations.

Conclusions:

• LIME 2.0 provides a more faithful representation of atomistic lipid interactions.
• The MS-IBI scheme enables temperature-independent parameterization for CG lipid models.
• LIME 2.0 is well-suited for studying lipid bilayers across various temperatures using DMD simulations.