Investigation of the morphological transition of a phospholipid bilayer membrane in an external electric field via molecular dynamics simulation.

Abstract

Elucidating the mechanisms for morphological transitions of the phospholipid bilayer membrane during cellular activity should lead to greater understanding of these membrane transitions and allow us to optimize biotechnologies such as drug delivery systems in organisms. To investigate the mechanism for and the dynamics of morphological changes in the phospholipid membrane, we performed molecular dynamics simulation of a phospholipid membrane with and without membrane protein under the influence of electric fields with different strengths. In the absence of membrane protein, it was possible to control the transition from one lamellar membrane morphology to another by applying a strong electric field. The strong electric field initially disordered the lipid molecules in the membrane, leading to the formation of a hydrophilic pore. The lipid molecules then spontaneously fused into a new lamellar membrane morphology. In the presence of membrane protein, a morphological transition from lamellar membrane to vesicle under the influence of a strong electric field was observed. Studying the complex transition dynamics associated with these changes in membrane morphology allowed us to gain deep insight into the electrofusion and electroporation that occur in the presence or absence of membrane protein, and the results obtained here should prove useful in work aimed at controlling membrane morphology. Graphical Abstract Memebrane morphological transition under the electric field of 0.6 V/nm with the membrane protein (down) and without membrane protein (up).