Conformational Study of an Artificial Metal-Dependent Regulation Site for Use in Designer Proteins
作者:Emmanuel Oheix、Neil Spencer、Lee A. Gethings、Anna F. A. Peacock
DOI:10.1002/zaac.201300131
日期:2013.7
were investigated as potential metal ion dependent switches in aqueous solution, and were found to predominantly adopt the transoïd conformation at physiological pH. Metal complexation with CuII and ZnII at this pH has been studied by UV/Vis, CD, NMR and ion-mobility mass spectrometry. ZnII titrations are consistent with the formation of a 1:1 ZnII:terpy-GS2 complex at pH 7.4, but bipy-GS2 was shown
本报告描述了谷胱甘肽的二聚化,以及其他含半胱氨酸的肽或蛋白质片段,具有 5, 5'-二取代-2, 2'-联吡啶或 6, 6”-二取代-2, 2':6 ',2”-三联吡啶单元。由此产生的 bipy-GS2 和 terpy-GS2 作为水溶液中潜在的金属离子依赖性开关进行了研究,发现在生理 pH 值下主要采用 transoïd 构象。已通过 UV/Vis、CD、NMR 和离子迁移质谱法研究了在此 pH 值下金属与 CuII 和 ZnII 的络合。ZnII 滴定与 pH 7.4 下 1:1 ZnII:terpy-GS2 复合物的形成一致,但 bipy-GS2 显示形成 1:1 和 1:2 复合物,前者在稀释的微摩尔条件下占主导地位。所得 1:1 复合物的形成常数被确定为 log KM 6。86 (bipy-GS2) 和 6.22 (terpy-GS2),与与应变的三联吡啶相比,对不受约束的联吡啶具有更高的亲和力。CuII