Zhou Jieying, Ridderbeek Korneel, Zou Peijian, Naden Aaron B, Gaussmann Stefan, Song Fangyuan, Falter-Braun Pascal, Kay Euan R, Sattler Michael, Cui Jian
Helmholtz Pioneer Campus, Helmholtz Munich, Neuherberg 85764, Germany.
Institute of Structural Biology, Molecular Targets and Therapeutics Center, Helmholtz Munich, Neuherberg 85764, Germany.
ACS Appl Opt Mater. 2025 Mar 15;3(3):676-688. doi: 10.1021/acsaom.4c00486. eCollection 2025 Mar 28.
Protein-protein interactions regulate essentially all cellular processes. Understanding these interactions, including the quantification of binding parameters, is crucial for unraveling the molecular mechanisms underlying cellular pathways and, ultimately, their roles in cellular physiology and pathology. Current methods for measuring protein-protein interactions generally require amino acid conjugation of fluorescent tags, complex instrumentation, large amounts of purified protein, or measurement at extended surfaces. Here, we present an elegant nanoparticle-based platform for the optical detection of protein-protein interactions in the solution phase. We synthesized gold-coated silver decahedral nanoparticles possessing high chemical stability and exceptional optical sensing properties. The nanoparticle surface is then tailored for specific binding to commonly used polyhistidine tags of recombinant proteins. Sequential addition of proteins to the nanoparticle suspension results in spectral shifts of the localized surface plasmon resonance that can be monitored by conventional UV-vis spectrophotometry. With this approach, we demonstrate both the qualitative detection of specific protein-protein interactions and the quantification of equilibrium and kinetic binding parameters between small globular proteins. Requiring minimal protein quantities and basic laboratory equipment, this technique offers a simple, economical, and modular approach to characterizing protein-protein interactions, holds promise for broad use in future studies, and may serve as a template for future biosensing technologies.
蛋白质-蛋白质相互作用基本上调控着所有的细胞过程。了解这些相互作用，包括结合参数的量化，对于阐明细胞通路背后的分子机制以及最终它们在细胞生理和病理中的作用至关重要。目前测量蛋白质-蛋白质相互作用的方法通常需要对荧光标签进行氨基酸偶联、复杂的仪器设备、大量的纯化蛋白质，或者在扩展表面上进行测量。在此，我们展示了一种基于纳米颗粒的精巧平台，用于在溶液相中光学检测蛋白质-蛋白质相互作用。我们合成了具有高化学稳定性和卓越光学传感特性的金包银十面体纳米颗粒。然后对纳米颗粒表面进行修饰，使其能够特异性结合重组蛋白常用的多组氨酸标签。向纳米颗粒悬浮液中依次添加蛋白质会导致局域表面等离子体共振的光谱位移，这可以通过传统的紫外-可见分光光度法进行监测。通过这种方法，我们既展示了对特定蛋白质-蛋白质相互作用的定性检测，也展示了对小球形蛋白质之间平衡和动力学结合参数的量化。该技术所需蛋白质量极少且仅需基本的实验室设备，为表征蛋白质-蛋白质相互作用提供了一种简单、经济且模块化的方法，有望在未来研究中得到广泛应用，并且可能成为未来生物传感技术的模板。
