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Determination of biomembrane bending moduli in fully atomistic simulations.

ABSTRACT: The bilayer bending modulus (Kc) is one of the most important physical constants characterizing lipid membranes, but precisely measuring it is a challenge, both experimentally and computationally. Experimental measurements on chemically identical bilayers often differ depending upon the techniques employed, and robust simulation results have previously been limited to coarse-grained models (at varying levels of resolution). This Communication demonstrates the extraction of Kc from fully atomistic molecular dynamics simulations for three different single-component lipid bilayers (DPPC, DOPC, and DOPE). The results agree quantitatively with experiments that measure thermal shape fluctuations in giant unilamellar vesicles. Lipid tilt, twist, and compression moduli are also reported.

SUBMITTER: Levine ZA

PROVIDER: S-EPMC4183605 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Determination of biomembrane bending moduli in fully atomistic simulations.

Levine Zachary A ZA Venable Richard M RM Watson Max C MC Lerner Michael G MG Shea Joan-Emma JE Pastor Richard W RW Brown Frank L H FL

Journal of the American Chemical Society 20140916 39

The bilayer bending modulus (Kc) is one of the most important physical constants characterizing lipid membranes, but precisely measuring it is a challenge, both experimentally and computationally. Experimental measurements on chemically identical bilayers often differ depending upon the techniques employed, and robust simulation results have previously been limited to coarse-grained models (at varying levels of resolution). This Communication demonstrates the extraction of Kc from fully atomisti ...[more]

PMID: 25202918

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