Many natural proteins function in oligomeric forms, which are critical for their sophisticated functions. The construction of protein assemblies has great potential for biosensors, enzyme catalysis, and biomedical applications. In designing protein assemblies, a critical process is to create protein–protein interaction (PPI) networks at defined sites of a target protein. Although a few methods are available for this purpose, most of them are dependent on existing PPIs of natural proteins to some extent. In this report, a metal-chelating amino acid, 2,2′-bipyridylalanine (BPA), was genetically introduced into defined sites of a monomeric protein and used to form protein oligomers. Depending on the number of BPAs introduced into the protein and the species of metal ions (Ni²⁺ and Cu²⁺), dimers or oligomers with different oligomerization patterns were formed by complexation with a metal ion. Oligomer sizes could also be controlled by incorporating two BPAs at different locations with varied angles to the center of the protein. When three BPAs were introduced, the monomeric protein formed a large complex with Ni²⁺. In addition, when Cu²⁺ was used for complex formation with the protein containing two BPAs, a linear complex was formed. The method proposed in this report is technically simple and generally applicable to various proteins with interesting functions. Therefore, this method would be useful for the design and construction of functional protein assemblies.

中文翻译：

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使用遗传结合的金属螯合氨基酸的金属介导的蛋白质组装

许多天然蛋白质以寡聚形式发挥功能，这对其复杂功能至关重要。蛋白质组件的构建对于生物传感器，酶催化和生物医学应用具有巨大潜力。在设计蛋白质装配时，关键的过程是在目标蛋白质的定义位点建立蛋白质-蛋白质相互作用（PPI）网络。尽管有几种方法可用于此目的，但大多数方法在一定程度上取决于天然蛋白质的现有PPI。在该报告中，将一种金属螯合氨基酸2,2'-联吡啶丙氨酸（BPA）遗传引入了单体蛋白质的定义位点，并用于形成蛋白质低聚物。取决于引入蛋白质的BPA数量和金属离子的种类（Ni ²⁺和Cu ²⁺），通过与金属离子络合形成具有不同低聚模式的二聚体或低聚物。还可以通过在不同位置掺入两个BPA来控制寡聚物的大小，这些BPA与蛋白质中心的角度不同。当引入三种双酚A时，单体蛋白与Ni ²⁺形成大的复合物。另外，当使用Cu ²⁺与包含两个BPA的蛋白质形成复合物时，形成线性复合物。本报告中提出的方法在技术上很简单，并且普遍适用于具有有趣功能的各种蛋白质。因此，该方法对于功能蛋白装配体的设计和构建将是有用的。