Long-range excitations in phospholipid membranes. (December 2019)

• Record Type: Journal Article
• Authors: Jaksch, Sebastian; Koutsioubas, Alexandros; Mattauch, Stefan; Holderer, Olaf; Frielinghaus, Henrich
• Is Part Of: Chemistry and physics of lipids. Volume 225(2019)
• Publication Date: 2019-12
• Subjects: Grazing incidence neutron spin echo -- GINSES -- Grazing incidence small-angle neutron scattering -- GISANS -- Phospholipids -- Membrane dynamics; Lipids -- Periodicals; Lipids -- Periodicals; Lipides -- Périodiques; Lipids; Periodicals; Electronic journals; 547.77
• DOI: 10.1016/j.chemphyslip.2019.104788
• Languages: English
• ISSNs: 0009-3084

Abstract

Graphical abstract: Abstract: We investigated the existence of long-range excitations and correlated structures in phospholipid membranes by means of grazing-incidence neutron spin echo spectroscopy, grazing-incidence small-angle neutron scattering, and corresponding theoretical calculations inspired by smectic-membrane theory. All these methods confirmed the existence of thermal excitations in the plane of the surface of the phospholipid membranes or the corresponding structures, respectively. Also, these measurements revealed a temperature dependence of these excitations. These excitations are associated with 100 nm in-plane correlations around physiological temperatures and of 75 nm at 16 °C. A single excitation has an energy around the μeV-regime. A temperature series revealed a high abundance at physiological temperatures and pronounced long-range in-plane structures, which are strongly suppressed at temperatures below 20 °C. From the length-scales and energy transfers involved we surmise that these excitations may play a role in several functions of the cell membranes such as stability and energy dissipation along the membrane. From a fundamental point of view, the observed behavior of those excitations is congruent with that of a quasi-particle (surface mode phonon, smomon ) that exists in the plane of phospholipid membranes.