Zeng Kai, Sun En-Jie, Liu Ze-Wen, Guo Junhui, Yuan Chengqing, Yang Ying, Xie Hao
School of Chemistry, Chemical Engineering, and Life Science, Wuhan University of Technology Wuhan 430070 China
School of Energy and Power Engineering, Wuhan University of Technology Wuhan 430070 China.
RSC Adv. 2020 Mar 20;10(19):11524-11534. doi: 10.1039/c9ra10473a. eCollection 2020 Mar 16.
Magnetic nanoparticles (MNPs) chelating with metal ions can specifically interact with poly-histidine peptides and facilitate immobilization and purification of proteins with poly-histidine tags. Fabrication of MNPs is generally complicated and time consuming. In this paper, we report the preparation of Ni(ii) ion chelated MNPs (Ni-MNPs) in two stages for protein immobilization and purification. In the first stage, organic ligands including pentadentate tris (carboxymethyl) ethylenediamine (TED) and tridentate iminodiacetic acid (IDA) and inorganic FeO-SiO MNPs were synthesized separately. In the next stage, ligands were grafted to the surface of MNPs and MNPs with a TED or IDA modified surface were acquired, followed by chelating with Ni(ii) ions. The Ni(ii) ion chelated forms of MNPs (Ni-MNPs) were characterized including morphology, surface charge, structure, size distribution and magnetic response. Taking a his-tagged glycoside hydrolase DspB (Dispersin B) as the protein representative, specific interactions were confirmed between DspB and Ni-MNPs. Purification of his-tagged DspB was achieved with Ni-MNPs that exhibited better performance in terms of purity and activity of DspB than commercial Ni-NTA. Ni-MNPs as enzyme carriers for DspB also exhibited good compatibility and reasonable reusability as well as improved performance in various conditions.
与金属离子螯合的磁性纳米颗粒（MNPs）可与多组氨酸肽特异性相互作用，并促进带有多组氨酸标签的蛋白质的固定化和纯化。MNPs的制备通常复杂且耗时。在本文中，我们报告了分两个阶段制备用于蛋白质固定化和纯化的镍（II）离子螯合磁性纳米颗粒（Ni-MNPs）。在第一阶段，分别合成了包括五齿三（羧甲基）乙二胺（TED）和三齿亚氨基二乙酸（IDA）在内的有机配体以及无机FeO-SiO MNPs。在下一阶段，将配体接枝到MNPs表面，获得表面经TED或IDA修饰的MNPs，随后与镍（II）离子螯合。对MNPs的镍（II）离子螯合形式（Ni-MNPs）进行了表征，包括形态、表面电荷、结构、尺寸分布和磁响应。以带有组氨酸标签的糖苷水解酶DspB（分散素B）作为蛋白质代表，证实了DspB与Ni-MNPs之间的特异性相互作用。用Ni-MNPs实现了对带有组氨酸标签的DspB的纯化，在DspB的纯度和活性方面，Ni-MNPs表现出比市售镍-亚氨基三乙酸（Ni-NTA）更好的性能。作为DspB酶载体的Ni-MNPs在各种条件下也表现出良好的兼容性、合理的可重复使用性以及改进的性能。
