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This content will become publicly available on August 1, 2025

Title: CHARMM‐GUI Membrane Builder for Lipid Droplet Modeling and Simulation
Abstract Lipid droplets (LDs) are organelles that are necessary for eukaryotic and prokaryotic metabolism and energy storage. They have a unique structure consisting of a spherical phospholipid monolayer encasing neutral lipids such as triacylglycerol (TAG). LDs have garnered increased interest for their implications in disease and for drug delivery applications. Consequently, there is an increased need for tools to study their structure, composition, and dynamics in biological contexts. In this work, we utilize CHARMM‐GUIMembrane Builderto simulate and analyze LDs with and without a plant LD protein, oleosin. The results show thatMembrane Buildercan generate biologically relevant all‐atom LD systems with relatively short equilibration times using a new TAG library having optimized headgroup parameters. TAG molecules originally inserted into a lipid bilayer aggregate in the membrane center, forming a TAG‐only core flanked by two monolayers. The TAG‐only core thickness stably grows with increasing TAG mole fraction. A 70 % TAG system has a core that is thick enough to house oleosin without its interactions with the distal leaflet or disruption of its secondary structure. We hope thatMembrane Buildercan aid in the future study of LD systems, including their structure and dynamics with and without proteins.  more » « less
Award ID(s):
2203362
PAR ID:
10538397
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
ChemPlusChem
Volume:
89
Issue:
8
ISSN:
2192-6506
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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