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Atomic Force Microscopy Imaging and Force Spectroscopy of Supported Lipid Bilayers
Published on: July 22, 2015
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Cholesterol induced asymmetry in DOPC bilayers probed by AFM force spectroscopy
Pranav R Adhyapak1, Suresh V Panchal1, Appala Venkata Ramana Murthy1
1Department of Applied Physics, Defence Institute of Advanced Technology (DIAT) DU, Girinagar, Pune, India.
Biochimica Et Biophysica Acta. Biomembranes
|February 7, 2018
Summary
Cholesterol impacts artificial lipid bilayers by increasing mechanical stability and creating leaflet asymmetry. This concentration-dependent effect, observed via atomic force microscopy, reveals insights into cell membrane biophysics.
Area of Science:
- Biophysics
- Materials Science
- Cell Biology
Background:
- Cholesterol's mechanical effects on lipid bilayers are known.
- Cholesterol's dynamic incorporation into bilayers and its concentration-dependent effects remain unclear.
Purpose of the Study:
- To investigate cholesterol's effect on dioleoylphosphatidylcholine (DOPC) bilayers as a function of concentration.
- To understand how cholesterol influences bilayer mechanical properties and leaflet asymmetry.
Main Methods:
- Atomic Force Microscopy (AFM) force spectroscopy was used.
- Artificial single-component dioleoylphosphatidylcholine (DOPC) lipid bilayers were studied.
- Cholesterol concentration was varied to observe its impact.
Main Results:
- Cholesterol increases the mechanical stability of DOPC bilayers.
- Cholesterol induces asymmetry across the inner and outer leaflets of the bilayer.
- The observed asymmetry is related to interleaflet coupling and is concentration-dependent.
Conclusions:
- Cholesterol's role extends beyond mechanical stabilization, introducing asymmetry.
- AFM probing of cholesterol concentration offers insights into lipid membrane mechanics.
- Findings correlate cholesterol-induced bilayer properties with cell membrane biophysical characteristics.
Keywords:
AsymmetryAtomic Force MicroscopyCholesterolDOPCForce spectroscopyLipid bilayerNanomechanical propertiesMore Related Videos
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