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arXiv · 0809.3040

Motional Coherence in Fluid Phospholipid Membranes

Maikel C. Rheinstadter·Jhuma Das·Elijah J. Flenner·Beate Bruening·Tilo Seydel·Ioan Kosztin
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Abstract

We report a high energy-resolution neutron backscattering study, combined with in-situ diffraction, to investigate slow molecular motions on nanosecond time scales in the fluid phase of phospholipid bilayers of 1,2-dimyristoyl-sn-glycero-3-phoshatidylcholine (DMPC) and DMPC/40% cholesterol (wt/wt). A cooperative structural relaxation process was observed. From the in-plane scattering vector dependence of the relaxation rates in hydrogenated and deuterated samples, combined with results from a 0.1 microsecond long all atom molecular dynamics simulation, it is concluded that correlated dynamics in lipid membranes occurs over several lipid distances, spanning a time interval from pico- to nanoseconds.

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Maikel C. Rheinstadter, Jhuma Das, Elijah J. Flenner, Beate Bruening, Tilo Seydel, Ioan Kosztin. 2008-09-18. Motional Coherence in Fluid Phospholipid Membranes. https://doi.org/10.1103/physrevlett.101.248106

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