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Updated: Jun 6, 2026
07:31
Realistic Membrane Modeling Using Complex Lipid Mixtures in Simulation Studies
Published on: September 1, 2023
Lipid Composition Modulates Secondary Structure at the Biocondensate-Membrane Interface.
1Department of Chemistry, University of Texas at Austin, Austin, TX 78712, USA.
Biorxiv : the Preprint Server for Biology
|June 5, 2026
Summary
Membrane charge significantly alters the structure of biomolecular condensates (BMCs) at the cell membrane interface. This study reveals how lipid bilayer charge impacts condensate organization and peptide conformation using advanced spectroscopy.
Area of Science:
- Biophysics
- Cell Biology
- Biochemistry
Background:
- Biomolecular condensates (BMCs) are crucial for cellular organization via liquid-liquid phase separation (LLPS).
- The molecular interactions between BMCs and cellular membranes are not well understood.
- Understanding these interfaces is key to deciphering cellular organization and function.
Purpose of the Study:
- To investigate the impact of membrane charge on the secondary structure of poly-GR within biomolecular condensates.
- To elucidate the molecular mechanisms governing condensate-membrane interactions.
- To provide insights into the electrostatic regulation of BMCs at membrane interfaces.
Main Methods:
- Utilized surface-enhanced infrared absorption spectroscopy (SEIRAS) to analyze peptide secondary structure.
- Employed SEIRAS to quantify poly-GR conformation within condensates at supported lipid bilayers.
- Investigated interactions with both neutral (POPC) and negatively charged (POPC/POPS) lipid bilayers.
Main Results:
- Neutral POPC bilayers maintained the β-sheet rich structure of the bulk condensate at the interface.
- Negatively charged POPC/POPS bilayers induced a decrease in β-sheet content and an increase in β-turns.
- Lipid headgroups were perturbed by the condensate, with greater effects observed on charged bilayers.
Conclusions:
- Membrane electrostatic charge is a critical regulator of biomolecular condensate secondary structure and interfacial behavior.
- Condensate-membrane interactions are modulated by lipid charge, affecting peptide conformation and hydration.
- This work offers molecular-level insights into how membranes control condensate organization.
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