Entropic part of the boundary energy in a lipid membrane

被引：0

作者：

Kheyfets B.B. ^{[1
]}

Mukhin S.I. ^{[1
]}

机构：

[1] National University of Science and Technology, MISIS, Moscow, 119049, Leninskii prospekt

来源：

Biochemistry (Moscow) Supplement Series A: Membrane and Cell Biology | 2011年 / 5卷 / 4期

关键词：

Flexible string model; Line tension; Lipid membrane; Raft;

D O I：

10.1134/S1990747811050072

中图分类号：

学科分类号：

摘要：

Two-phase lipid membrane is modeled with lipids of different bending rigidity of hydrophobic tails: domains consist of "rigid" lipid liquid condensed phase and are surrounded by the "flexible" lipid liquid expanded phase. Within the framework of the earlier proposed model of flexible strings, entropic contribution not including mismatch energy is calculated analytically. "Entropic" line tension is found to be weakly dependent on the domain radius. According to the model, it is shown that merely "entropic mismatch" is not enough for the domain formation. In the paper it is assumed that lipids at the boundary, on the average, have larger area than the ones in the volume. This leads to an increase of energy of boundary lipids. Cases of lipids with nearly the same bending rigidities and with strongly different ones are considered. Free energy is calculated using Taylor expansion on the difference of area of lipids at the domain's boundary and in the volume. Based on the calculated boundary energy domain stability in the finite system is estimated. © Pleiades Publishing, Ltd., 2011.

引用

页码：392 / 399

页数：7

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