Generation of dynamic structures in nonequilibrium reactive bilayers

TL;DR

This paper introduces a nonequilibrium model for reactive bilayers with components inducing different curvatures, revealing complex dynamic behaviors like traveling and oscillatory patterns driven by external forces.

Contribution

It extends previous models by incorporating active effects of reactions on membrane curvature, demonstrating rich spatiotemporal phenomena in reactive bilayer systems.

Findings

Finite domain sizes due to reaction-induced mixing

Emergence of traveling and oscillatory patterns

Validation through stability analysis and simulations

Abstract

We present a nonequlibrium approach for the study of a flexible bilayer whose two components induce distinct curvatures. In turn, the two components are interconverted by an externally promoted reaction. Phase separation of the two species in the surface results in the growth of domains characterized by different local composition and curvature modulations. This domain growth is limited by the effective mixing due to the interconversion reaction, leading to a finite characteristic domain size. In addition to these effects, first introduced in our earlier work [Phys. Rev. E {\bf 71}, 051906 (2005)], the important new feature is the assumption that the reactive process actively affects the local curvature of the bilayer. Specifically, we suggest that a force energetically activated by external sources causes a modification of the shape of the membrane at the reaction site. Our results show the appearance of a rich and robust dynamical phenomenology that includes the generation of traveling and/or oscillatory patterns. Linear stability analysis, amplitude equations and numerical simulations of the model kinetic equations confirm the occurrence of these spatiotemporal behaviors in nonequilibrium reactive bilayers.