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Realistic Membrane Modeling Using Complex Lipid Mixtures in Simulation Studies
Published on: September 1, 2023
Lipid membranes with transmembrane proteins in shear flow
Atefeh Khoshnood1, Hiroshi Noguchi, Gerhard Gompper
1Department of Mechanical Engineering, Computational Mechanics Laboratory, Sharif University of Technology, Azadi Avenue, Tehran, Iran. atefeh_khoshnood@mech.sharif.edu
The Journal of Chemical Physics
|January 26, 2010
Summary
Embedded proteins significantly increase friction in lipid bilayer membranes during shear flow. This friction depends on protein size and aggregation, with proteins orienting to reduce drag.
Area of Science:
- Biophysics
- Materials Science
- Computational Chemistry
Background:
- Lipid bilayer membranes are fundamental to cell structure and function.
- Embedded proteins influence membrane dynamics and properties.
- Understanding protein-lipid interactions is crucial for membrane biophysics.
Purpose of the Study:
- To investigate the impact of embedded proteins on lipid bilayer membrane dynamics under shear flow.
- To analyze how protein characteristics affect intermonolayer friction.
- To explore protein behavior and orientation in response to shear forces.
Main Methods:
- Coarse-grained molecular simulations were utilized.
- Lipids were modeled as short polymers.
- Transmembrane proteins were represented as connected hydrophobic molecules.
Main Results:
- Rigid proteins aggregate in equilibrium, while flexible proteins do not.
- Transmembrane proteins increase intermonolayer friction in shear flow.
- Friction coefficient is influenced by lipid chain length, membrane tension, protein length, and cluster size.
- Friction increases with protein length (positive mismatch) and cluster size.
- Proteins orient along the flow direction to minimize friction, exhibiting large orientation angle fluctuations.
Conclusions:
- Embedded proteins significantly alter the frictional properties of lipid bilayers in shear flow.
- Protein aggregation and length are key factors modulating membrane friction.
- Protein orientation in flow is a dynamic response to reduce frictional forces.
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