Permeabilizing Phospholipid Bilayers with Non-normal Electric Fields
F Castellani1,2, J Teissié3, P T Vernier4
1Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, 23508, USA.
The Journal of Membrane Biology
|November 3, 2017
Summary
Molecular dynamics simulations reveal how electric fields affect cell membranes. The tangential component of the electric field, not just the perpendicular one, influences lipid electropore formation, offering new insights into membrane permeability.
Area of Science:
- Biophysics
- Computational Biology
- Membrane Science
Background:
- Molecular dynamics simulations have advanced understanding of electropermeabilization (electroporation) since 2003.
- Previous studies conventionally applied electric fields perpendicular to lipid bilayers.
Purpose of the Study:
- To investigate lipid electropore formation under electric fields applied at oblique angles to the membrane surface.
- To determine the effect of the tangential electric field component on membrane electroporation.
Main Methods:
- Utilized molecular dynamics simulations to model lipid bilayers.
- Simulated electroporation with electric fields applied at angles non-normal to the membrane.
Main Results:
- The tangential component of the electric field was found to have a small but significant effect on electropore formation.
- This contrasts with the conventional assumption of only normal field effects.
Conclusions:
- The orientation of the electric field relative to the membrane surface is a crucial factor in electroporation.
- Findings suggest a more nuanced understanding of electroporation mechanisms is needed, considering oblique field effects.
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