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Updated: May 12, 2026
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Neutron Spin Echo Spectroscopy as a Unique Probe for Lipid Membrane Dynamics and Membrane-Protein Interactions
Published on: May 27, 2021
Differential equilibration in cis- and trans-ceramide monolayers: A molecular dynamics study.
Leonor Saiz1, Jose M G Vilar2,3,4, Félix M Goñi2,3,5
1Department of Biomedical Engineering, University of California, 451 East Health Sciences Drive, Davis, California 95616, USA.
The Journal of Chemical Physics
|May 11, 2026
Summary
The trans configuration of ceramides is crucial for their function. Computational simulations reveal that trans-ceramides more readily form ordered monolayers compared to cis-ceramides due to differences in water interactions.
Area of Science:
- Biophysics
- Materials Science
- Computational Chemistry
Background:
- Ceramides, N-acyl sphingosine derivatives, are vital for cell signaling and skin barrier function.
- Naturally occurring unsaturated sphingosines predominantly feature a trans double bond, essential for ceramide functionality.
Purpose of the Study:
- To investigate the configurational specificity of the trans double bond in ceramides.
- To computationally study the equilibration properties of cis- and trans-ceramide monolayers.
Main Methods:
- Developed a reverse-pathway ordered-start atomistic simulation protocol for efficient molecular dynamics.
- Performed large-scale simulations of lipid monolayers hydrated with water slabs.
- Utilized virtual compression and expansion processes with energy minimization.
Main Results:
- Trans-ceramide monolayers adopt ordered conformations more readily than cis-ceramides.
- Significant differences observed in water interactions with polar heads between cis- and trans-isomers.
- Cis-ceramides showed an inability to form intramolecular H-bonds between OH groups.
Conclusions:
- The trans configuration facilitates easier ordering of ceramide monolayers.
- Isomer-specific water interactions influence the conformational behavior of ceramides.
- Understanding these differences is key to ceramide-related biological functions and material properties.
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