Detection of lipid raft domains in neutral and anionic Langmuir monolayers and bilayers of complex lipid composition
Detection of lipid raft domains in neutral and anionic Langmuir monolayers and bilayers of complex lipid composition
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DOI：
10.1039/c2sm06835d
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发表时间：
2012-01-01
期刊：
影响因子：
3.4
通讯作者：
Winter, Roland
中科院分区：
文献类型：
--
作者：
Evers, Florian;Jeworrek, Christoph;Winter, Roland
鉴于细胞膜的复杂性和异质性，本研究对由多组分脂质混合物组成的脂质单层和双层的结构和横向有序性进行了研究和比较。这些复杂的模型生物膜系统代表了有价值的模型系统，例如。G.用于研究脂质-肽相互作用，其中需要使用单层和双层技术的集成原位多技术方法。两性离子（3组分）和阴离子（5组分）非均相模型膜系统的特征在于，由饱和和不饱和磷脂以及胆固醇组成。通过表面X射线散射技术分析了脂质单分子层，并确定了作为表面压力和温度的函数的垂直结构（电子密度分布）和面内有序度。相应的结构和横向组织的双层膜，其特征在于通过原子力显微镜。单分子膜和双分子膜都显示出有序畴的形成，然而，单分子膜的尺寸要小得多，温度稳定性也不同。此外，脂质单层的电荷密度对有序结构域的大小以及脂质分子的分子间距离具有显著影响。
In reference to the complexity and heterogeneity of cellular membranes, the structure and lateral ordering of lipid monolayers and bilayers composed of multi-component lipid mixtures have been investigated and compared in the present study. These complex model biomembrane systems represent valuable model systems, e. g. for studies of lipid-peptide interactions, where an integrated in situ multi-technique approach using both monolayer and bilayer techniques is required. A zwitterionic (3 components) and an anionic (5 components) heterogeneous model membrane system have been characterized that consist of saturated and unsaturated phospholipids as well as cholesterol. Lipid monolayers were analyzed by surface X-ray scattering techniques, and both the vertical structure (electron density profile) and the degree of in-plane ordering were determined as a function of surface pressure and temperature. The corresponding structure and lateral organisation of the bilayer membranes were characterized by atomic force microscopy. Both monolayers and bilayers reveal ordered domain formation, the monolayer ones being of much smaller size and different temperature stability, however. Furthermore, the charge density of the lipid monolayer has a drastic influence on the size of ordered domains as well as the intermolecular distances of the lipid molecules.