Structural and biophysical properties of a synthetic channel-forming peptide: designing a clinically relevant anion selective pore.
Structural and biophysical properties of a synthetic channel-forming peptide: designing a clinically relevant anion selective pore.
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合成通道形成肽的结构和生物物理特性：设计临床相关的阴离子选择性孔。
DOI：
10.1016/j.bbamem.2011.07.037
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Tomich,JM
中科院分区：
文献类型：
--
作者：
Bukovnik,U;Gao,J;Cook,GA;Shank,LP;Seabra,MB;Schultz,BD;Iwamoto,T;Chen,J;Tomich,JM
来自配体门控离子通道半胱环超家族的通道形成肽的设计、合成、建模和体外测试是正在进行的研究重点的一部分。基于脊髓甘氨酸受体α亚基的M2跨膜片段，已经制备了300多个不同的序列。其中许多序列是水溶性单体，很容易插入生物膜中，在生物膜中进行超分子组装，产生具有一系列选择性和电导的通道。选择进一步修饰的序列以产生最佳的先导化合物取决于几个关键的生物物理特性：产生通道活性的低溶液浓度、更大的整体电导和增强的离子选择性。序列 NK4-M2GlyR T19R、S22W (KKKKPARVGLGITTVLTMRTQW) 满足了这些标准。该肽的结构已通过溶液核磁共振作为洗涤剂胶束中的单体进行分析，在膜环境中模拟为五螺旋束，通过半胱氨酸扫描进行修饰，并研究了选定脂质成分的脂质体中的插入效率。总而言之，这些结果定义了膜中该序列的结构和关键生物物理特性。该模型提供了一个初始支架，从中可以提出并测试合理的取代以调节阴离子选择性。本文是题为“膜中的蛋白质折叠”特刊的一部分。
The design, synthesis, modeling and in vitro testing of channel-forming peptides derived from the cys-loop superfamily of ligand-gated ion channels are part of an ongoing research focus. Over 300 different sequences have been prepared based on the M2 transmembrane segment of the spinal cord glycine receptor α-subunit. A number of these sequences are water-soluble monomers that readily insert into biological membranes where they undergo supramolecular assembly, yielding channels with a range of selectivities and conductances. Selection of a sequence for further modifications to yield an optimal lead compound came down to a few key biophysical properties: low solution concentrations that yield channel activity, greater ensemble conductance, and enhanced ion selectivity. The sequence NK4-M2GlyR T19R, S22W (KKKKPARVGLGITTVLTMRTQW) addressed these criteria. The structure of this peptide has been analyzed by solution NMR as a monomer in detergent micelles, simulated as five-helix bundles in a membrane environment, modified by cysteine-scanning and studied for insertion efficiency in liposomes of selected lipid compositions. Taken together, these results define the structural and key biophysical properties of this sequence in a membrane. This model provides an initial scaffold from which rational substitutions can be proposed and tested to modulate anion selectivity. This article is part of a Special Issue entitled: Protein Folding in Membranes.