A Self-Assembled Monolayer for the Binding and Study of Histidine-Tagged Proteins by Surface Plasmon Resonance
作者:George B. Sigal、Cynthia Bamdad、Alcide Barberis、Jack Strominger、George M. Whitesides
DOI:10.1021/ac9504023
日期:1996.2.1
monolayer (SAM) that selectively binds proteins whose primary sequence terminates with a His-tag: a stretch of six histidines commonly incorporated in recombinant proteins to simplify purification. The SAM was prepared by the adsorption onto a gold surface of a mixture of two alkanethiols: one thiol that terminated with a nitrilotriacetic acid (NTA) group, a group that forms a tetravalent chelate with Ni(II)
本文报道了自组装单分子层(SAM)的产生,该分子选择性结合主要序列以His-tag终止的蛋白质:通常整合在重组蛋白中的六个组氨酸片段,以简化纯化过程。通过将两种链烷硫醇的混合物吸附到金表面上来制备SAM:一种以亚硝基三乙酸(NTA)基团终止的硫醇,与Ni(II)形成四价螯合物的基团和另一种以Ni(II)形成四价螯合物的基团具有三(乙二醇)基团的基团,该基团可抵抗蛋白质的吸附。通过组氨酸与螯合至表面NTA基团的Ni(II)离子上的两个空位相互作用,将带有组氨酸标签的蛋白质与SAM结合。用模型蛋白进行的研究表明,结合是对带有His标签的蛋白特异的,并且需要在表面存在Ni(II)。固定化的带有His标签的蛋白在pH 7.2的缓冲盐水中具有动力学稳定性,但可以通过用200 mM的咪唑处理来解吸。对两个模型系统的表面等离振子共振研究表明,与通过共价偶联固定在葡聚糖凝胶薄层中的蛋白质相比,吸附在NTA