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Atomic Force Microscopy Imaging and Force Spectroscopy of Supported Lipid Bilayers
Published on: July 22, 2015
Shape relaxations in a fluid supported membrane during hydrolysis by phospholipase A(2)
Uffe Bernchou Jensen1, Adam Cohen Simonsen
1MEMPHYS Center for Biomembrane Physics, Physics Department, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
Biochimica Et Biophysica Acta
|August 16, 2005
Summary
Fluid membranes undergoing hydrolysis by phospholipase A(2) were visualized for the first time. Hydrolysis spreads from existing holes and new ones form, with membrane shape influenced by line tension and Rayleigh instabilities.
Area of Science:
- Biophysics
- Materials Science
- Chemical Biology
Background:
- Phospholipase A(2) (PLA2) is crucial for membrane remodeling.
- Understanding PLA2-mediated hydrolysis dynamics is key to cellular processes.
- Fluid-supported membrane behavior under enzymatic action requires detailed visualization.
Purpose of the Study:
- To visualize the dynamic behavior of fluid-supported membranes during phospholipase A(2) hydrolysis.
- To elucidate the mechanisms of membrane hole formation and expansion.
- To investigate the interplay between hydrolysis and membrane line tension.
Main Methods:
- Time-resolved fluorescence imaging was employed to capture membrane dynamics.
- Observation of hydrolysis progression from existing hole boundaries and de novo nucleation.
- Analysis of membrane shape evolution influenced by hydrolysis and line tension effects.
Main Results:
- Hydrolysis initiated after a lag phase, spreading from existing holes and forming new ones.
- Membrane boundary shape was dictated by both hydrolysis and line tension-induced relaxations.
- Rayleigh instabilities in membrane rims and domain coarsening-like phenomena were observed.
Conclusions:
- First-time visualization reveals complex dynamics of PLA2-driven membrane hydrolysis.
- Line tension significantly influences membrane morphology during enzymatic degradation.
- Membrane hole dynamics resemble domain coarsening, with smaller holes decaying near larger ones.
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