Incorporation of channel-forming peptides in a Hg-supported lipid bilayer
Incorporation of channel-forming peptides in a Hg-supported lipid bilayer
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DOI：
10.1016/j.jelechem.2004.09.032
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发表时间：
2005-02-15
影响因子：
4.5
通讯作者：
Moncelli, MR
中科院分区：
文献类型：
--
作者：
Becucci, L;Guidelli, R;Moncelli, MR
通道形成肽gramicidin和alamethicin结合在汞支持的脂质双分子层中，该双分子层由系留的硫脂单分子层和自组装的二酰基磷脂酰胆碱单分子层组成。该硫脂由一个易于形成3（10）螺旋结构的六肽链组成，其n端末端有一个巯基，用于锚定金属，而c端则与二肉豆醇酰磷脂酰乙醇胺的极性头共价连接。六肽部分具有两个三乙烯氧侧链，具有令人满意的亲水性，旨在使锚定的硫肽链保持足够的距离，以便容纳水分子和无机离子，并为整合蛋白质创造合适的环境。用阻抗谱法检测了加入革兰杀菌素和阿拉梅辛后这种仿生膜的电导变化。利用汞溶液间相的简单静电模型估计了六肽链的表面偶极电势和脂质双分子层的跨膜电势。(C) 2004 Elsevier B.V.版权所有
The channel-forming peptides gramicidin and alamethicin were incorporated in a mercury-supported lipid bilayer composed of a tethered thiolipid monolayer with a self-assembled dioleoylphosphatidylcholine monolayer on top of it. The thiolipid consists of a hexapeptide chain with a high tendency to form a 3(10)-helical structure, which terminates at the N-terminus end with a sulfydryl group for anchoring to the metal while the C-terminus end is covalently linked to the polar head of dimyristolylphosphatidylethanolamine. The hexapeptide moiety has two triethyleneoxy side chains that impart a satisfactory hydrophilicity and are intended to keep the anchored thiolpeptide chains sufficiently apart, so as to accommodate water molecules and inorganic ions and to create a suitable environment for the incorporation of integral proteins. Changes in the conductance of this biomimetic membrane following the incorporation of gramicidin and alamethicin were detected by impedance spectroscopy. The surface dipole potential of the hexapeptide chain and the transmembrane potential of the lipid bilayer were estimated by using a simple electrostatic model of the mercury\solution interphase. (C) 2004 Elsevier B.V. All rights reserved.