Design, structures and functions of stabilized artificial ion channels

由多孢木霉产生的20个残基肽，即Trichoderma polysporum，在平面脂质双层膜上形成电压依赖性离子通道。为了明确通道稳定的主要因素和开发新的功能材料，如人工离子通道，合成了三磷蛋白衍生物，包括模板组装二聚体和四聚体以及两种二硫连接二聚体，并研究了它们的通道形成特性。本研究得到的结果总结如下：1。截断和拉长的肽衍生物诱导的通道是不稳定的，这表明肽长度与膜厚度的拟合是非常重要的。亲结结构对于电压依赖性通道的形成不是必需的，但对于形成稳定的大孔径通道是非常重要的。肽亲脂性促进肽聚集，这与通道稳定性不一致。通道的稳定性受多肽、脂质和水组成的超分子状态的影响。所有化学组装的肽（螺旋束）形成非常持久的通道，支持肽通道可以通过桶状壁模型来解释。稳定通道的成功形成可能导致新型功能材料的开发。

20-residue peptaibols, trichosporins-B produced by the fungus Trichoderma polysporum, forms voltage-dependent ion channels in planar lipid bilayr membranes. To clarify primary factors for channel stabilization and to develop new functional materials such as artificial ion channels, trichosporin derivatives including a template-assembled dimer and tetramer and two disulfide-linked dimers were synthesized and their channel-forming properties were investigated.The results obtained in this study were summarized as followes ;1.The chennels induced by truncated and elongated derivertives were unstable, suggesting that peptide length fitting the membrane thickness is quite important.2.The Pro-kinked structure is not essential for voltage-dependent channel formation and very important for forming stable channels with large pore size.3.Peptide lipophilicity promotes peptide aggregation and this is not in accordance with channel stability.4.Stability of channels is influenced by the states of supermolecules consisting of pepides, lipids and water.5.All chemically assembled peptides (helix bundle) form very long-lasting channels, supporting that peptaibol channels can be explained through the barrel stave model.6.Success in formation of the stable channels may lead to developing novel functional materials.