Department of Organic Chemistry, University of Vienna, Währinger Strasse 38, A-1090 Vienna, Austria.
Beilstein J Org Chem. 2012;8:448-55. doi: 10.3762/bjoc.8.51. Epub 2012 Mar 27.
A novel reporter system, which is applicable to the (19)F NMR investigation of protein interactions, is presented. This approach uses 2-F-labeled maltose as a spy ligand to indirectly probe protein-ligand or protein-protein interactions of proteins fused or tagged to the maltose-binding protein (MBP). The key feature is the simultaneous NMR observation of both (19)F NMR signals of gluco/manno-type-2-F-maltose-isomers; one isomer (α-gluco-type) binds to MBP and senses the protein interaction, and the nonbinding isomers (β-gluco- and/or α/β-manno-type) are utilized as internal references. Moreover, this reporter system was used for relative affinity studies of fluorinated and nonfluorinated carbohydrates to the maltose-binding protein, which were found to be in perfect agreement with published X-ray data. The results of the NMR competition experiments together with the established correlation between (19)F chemical shift data and molecular interaction patterns, suggest valuable applications for studies of protein-ligand interaction interfaces.
本文介绍了一种适用于（19）F NMR 研究蛋白质相互作用的新型报告系统。该方法使用 2-F 标记的麦芽糖作为间谍配体，间接探测融合或标记麦芽糖结合蛋白（MBP）的蛋白质与配体或蛋白质-蛋白质之间的相互作用。关键特征是同时观察葡萄糖/甘露糖-2-F-麦芽糖异构体的两个（19）F NMR 信号；一种异构体（α-葡糖型）与 MBP 结合并感知蛋白质相互作用，而非结合异构体（β-葡糖型和/或α/β-甘露糖型）则用作内标。此外，该报告系统还用于相对亲和性研究氟代和非氟代碳水化合物与麦芽糖结合蛋白的相互作用，其结果与已发表的 X 射线数据完全一致。NMR 竞争实验的结果以及（19）F 化学位移数据与分子相互作用模式之间的关系表明，该报告系统在研究蛋白质-配体相互作用界面方面具有重要的应用价值。
