Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, Saint Louis, MO, 63130, USA.
Division of Biological & Biomedical Sciences, Washington University in St. Louis, Saint Louis, MO, 63130, USA.
Nat Commun. 2019 Jul 25;10(1):3317. doi: 10.1038/s41467-019-11285-8.
Protein nanostructures with precisely defined geometries have many potential applications in catalysis, sensing, signal processing, and drug delivery. While many de novo protein nanostructures have been assembled via non-covalent intramolecular and intermolecular interactions, a largely unexplored strategy is to construct nanostructures by covalently linking multiple individually folded proteins through site-specific ligations. Here, we report the synthesis of single-chain protein nanostructures with triangular and square shapes made using multiple copies of a three-helix bundle protein and split intein chemistry. Coarse-grained simulations confirm the experimentally observed flexibility of these nanostructures, which is optimized to produce triangular structures with high regularity. These single-chain nanostructures also display ultra-high thermostability, resist denaturation by chaotropes and organic solvents, and have applicability as scaffolds for assembling materials with nanometer resolution. Our results show that site-specific covalent ligation can be used to assemble individually folded proteins into single-chain nanostructures with bespoke architectures and high stabilities.
具有精确定义几何形状的蛋白质纳米结构在催化、传感、信号处理和药物输送等方面具有许多潜在的应用。虽然许多从头开始的蛋白质纳米结构是通过非共价的分子内和分子间相互作用组装的，但一个很大程度上尚未开发的策略是通过通过位点特异性连接将多个单独折叠的蛋白质通过共价键连接起来来构建纳米结构。在这里，我们报告了使用多个三螺旋束蛋白和分裂内含肽化学合成具有三角形和正方形形状的单链蛋白质纳米结构。粗粒度模拟证实了这些纳米结构的实验观察到的灵活性，该灵活性经过优化以产生具有高规则性的三角形结构。这些单链纳米结构还表现出超高的热稳定性，能够抵抗变构剂和有机溶剂的变性，并且可用作组装具有纳米分辨率的材料的支架。我们的结果表明，位点特异性共价连接可以用于将单独折叠的蛋白质组装成具有定制结构和高稳定性的单链纳米结构。
