Simulation of polyethylene glycol and calcium-mediated membrane fusion

Journal article
Polymers
Lipid membranes
Author

Martina Pannuzzo, Djurre H. De Jong, Antonio Raudino, and Siewert J. Marrink

Doi

https://doi.org/10.1063/1.4869176

Citation (APA 7)

Pannuzzo, M., De Jong, D. H., Raudino, A., & Marrink, S. J. (2014). Simulation of polyethylene glycol and calcium-mediated membrane fusion. The Journal of Chemical Physics, 140(12).

Abstract

We report on the mechanism of membrane fusion mediated by polyethylene glycol (PEG) and Ca2+ by means of a coarse-grained molecular dynamics simulation approach. Our data provide a detailed view on the role of cations and polymer in modulating the interaction between negatively charged apposed membranes. The PEG chains cause a reduction of the inter-lamellar distance and cause an increase in concentration of divalent cations. When thermally driven fluctuations bring the membranes at close contact, a switch from cis to trans Ca2+-lipid complexes stabilizes a focal contact acting as a nucleation site for further expansion of the adhesion region. Flipping of lipid tails induces subsequent stalk formation. Together, our results provide a molecular explanation for the synergistic effect of Ca2+ and PEG on membrane fusion.