Zhao Zhuangyu, Rudman Nathan A, Dmochowski Ivan J
Department of Chemistry, University of Pennsylvania, 231 S. 34th St., Philadelphia, Pennsylvania 19104, United States.
ACS Omega. 2024 Jun 28;9(27):29331-29338. doi: 10.1021/acsomega.4c00968. eCollection 2024 Jul 9.
There is a need for photochemical tools that allow precise control of protein structure and function with visible light. We focus here on the -tetrazine moiety, which can be installed at a specific protein site via the reaction between dichlorotetrazine and two adjacent sulfhydryl groups. Tetrazine's compact size enables structural mimicry of native amino acid linkages, such as an intramolecular salt bridge or disulfide bond. In this study, we investigated tetrazine installation in three different proteins, where it was confirmed that the cross-linking reaction is highly efficient in aqueous conditions and site-specific when two cysteines are located proximally: the S-S distance was 4-10 Å. As shown in maltose binding protein, the tetrazine cross-linker can replace an interdomain salt bridge crucial for xenon binding and serve as a visible-light photoswitch to modulate Xe NMR contrast. This work highlights the ease of aqueous tetrazine bioconjugation and its applications for protein photoregulation.
需要能够通过可见光精确控制蛋白质结构和功能的光化学工具。我们在此关注四嗪部分，它可以通过二氯四嗪与两个相邻巯基之间的反应安装在特定的蛋白质位点上。四嗪紧凑的结构使其能够模拟天然氨基酸连接的结构，如分子内盐桥或二硫键。在本研究中，我们研究了在三种不同蛋白质中安装四嗪的情况，结果证实，当两个半胱氨酸靠近时，交联反应在水性条件下高效且具有位点特异性：S-S距离为4-10埃。如麦芽糖结合蛋白所示，四嗪交联剂可以取代对氙结合至关重要的结构域间盐桥，并作为可见光光开关来调节Xe NMR对比度。这项工作突出了水性四嗪生物共轭的简便性及其在蛋白质光调节中的应用。
