Measuring interactions of DNA with nanoporous protein crystals by atomic force microscopy
Measuring interactions of DNA with nanoporous protein crystals by atomic force microscopy
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DOI：
10.1039/d1nr01703a
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发表时间：
2021-06-09
期刊：
影响因子：
6.7
通讯作者：
Kipper, Matt J.
中科院分区：
文献类型：
--
作者：
Wang, Dafu;Stuart, Julius D.;Kipper, Matt J.
交联多孔蛋白晶体是一种新型生物材料，可用于包裹、稳定和组织客体分子、纳米颗粒和生物片段。在这项研究中，首次通过高分辨率原子力显微镜（AFM）和化学力显微镜定量测量了DNA链与多孔蛋白晶体的联合相互作用。用高分辨率原子力显微镜观察了具有异常大孔隙的蛋白质晶体的表面结构。力-距离（F-D）曲线也可以使用经过修饰的AFM尖端来呈现或捕获DNA。AFM尖端的修饰允许尖端共价结合预先加载在蛋白质晶体纳米孔中的DNA。修饰后的尖端可以定量研究DNA分子与蛋白质晶体的相互作用，同时详细揭示了浸泡在缓冲液中的蛋白质晶体表面的形态，从而保留了可能被干燥破坏或破坏的蛋白质晶体的结构和性质。六方空间群在晶体表面表现出来，DNA和多孔蛋白质晶体之间的强相互作用也是如此。总之，这项研究进一步加深了我们对一种新的基于蛋白质的生物材料如何用于结合来宾DNA组装的理解。
Crosslinked porous protein crystals are a new biomaterial that can be engineered to encapsulate, stabilize, and organize guest molecules, nanoparticles, and biological moieties. In this study, for the first time, the combined interactions of DNA strands with porous protein crystals are quantitatively measured by high-resolution atomic force microscopy (AFM) and chemical force microscopy. The surface structure of protein crystals with unusually large pores was observed in liquid via high-resolution AFM. Force-distance (F-D) curves were also obtained using AFM tips modified to present or capture DNA. The modification of AFM tips allowed the tips to covalently bind DNA that was pre-loaded in the protein crystal nanopores. The modified tips enabled the interactions of DNA molecules with protein crystals to be quantitatively studied while revealing the morphology of the buffer-immersed protein crystal surface in detail, thereby preserving the structure and properties of protein crystals that could be disrupted or destroyed by drying. The hexagonal space group was manifest at the crystal surface, as were the strong interactions between DNA and the porous protein crystals in question. In sum, this study furthered our understanding of how a new protein-based biomaterial can be used to bind guest DNA assemblies.