通过X射线反射率研究作为脂质组成函数的茎形成。

Stalk formation as a function of lipid composition studied by X-ray reflectivity.

作者信息

Khattari Ziad, Köhler Sebastian, Xu Yihui, Aeffner Sebastian, Salditt Tim

机构信息

Department of Physics, Hashemite University, 13115 Zarqa, Jordan.

Institut für Röntgenphysik, Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany.

出版信息

Biochim Biophys Acta. 2015 Jan;1848(1 Pt A):41-50. doi: 10.1016/j.bbamem.2014.08.010. Epub 2014 Sep 28.

DOI:10.1016/j.bbamem.2014.08.010

PMID:25261611

Abstract

We have investigated the structure and interaction of solid-supported multilamellar phospholipid bilayers in view of stalk formation as model systems for membrane fusion. The multi-component bilayers were composed of ternary and quaternary mixtures, containing phosphatidylcholines, phosphatidylethanolamines, sphingomyelin, cholesterol, diacylglycerol, and phosphatidylinositol. Analysis of the obtained electron density profiles and the pressure-distance curves reveals systematic changes in structure and hydration repulsion. The osmotic pressure needed to induce stalk formation at the transition from the fluid lamellar to the rhombohedral phase indicates how membrane fusion properties are modified by bilayer composition.

摘要

我们研究了固体支持的多层磷脂双分子层的结构和相互作用，将其作为膜融合的模型系统来研究茎状结构的形成。这些多组分双分子层由三元和四元混合物组成，包含磷脂酰胆碱、磷脂酰乙醇胺、鞘磷脂、胆固醇、二酰基甘油和磷脂酰肌醇。对所得电子密度分布和压力-距离曲线的分析揭示了结构和水合排斥力的系统性变化。在从流体层状相转变为菱面体相时诱导茎状结构形成所需的渗透压表明了双层组成如何改变膜融合特性。