Ion pump activity generates fluctuating electrostatic forces in biomembranes
MEMPHYS - Center for Biomembrane Physics, Department of Physics and Chemistry, University of Southern Denmark - Campusvej 55, 5230 Odense M, Denmark, EU
Accepted: 28 August 2011
We study the non-equilibrium dynamics of lipid membranes with proteins that actively pump ions across the membrane. We find that the activity leads to a fluctuating force distribution due to electrostatic interactions arising from the variation in the dielectric constant across the membrane. By applying a multipole expansion we find effects on both the tension and bending rigidity dominated parts of the membranes fluctuation spectrum. We discuss how our model compares with previous studies of force-multipole models.
PACS: 87.16.dp – Transport, including channels, pores, and lateral diffusion / 41.20.-q – Applied classical electromagnetism / 05.70.Np – Interface and surface thermodynamics
© EPLA, 2011