Fafarman Aaron T, Webb Lauren J, Chuang Jessica I, Boxer Steven G
Department of Chemistry, Stanford University, Stanford, CA 94305-5080, USA.
J Am Chem Soc. 2006 Oct 18;128(41):13356-7. doi: 10.1021/ja0650403.
The nitrile stretching mode of the thiocyanate moiety is a nearly ideal probe for measuring the local electric field arising from the organized environment of the interior of a protein. Nitriles were introduced into three proteins: ribonuclease S (RNase S), human aldose reductase (hALR2), and the reaction center (RC) of Rhodobacter capsulatus, through a facile synthetic scheme for the transformation of cysteine residues into thiocyanatoalanine. Vibrational Stark effect spectroscopy and Fourier transform infrared spectroscopy on the modified proteins demonstrated that thiocyanate residues are a highly general tool for probing electrostatic fields in proteins.
硫氰酸酯部分的腈拉伸模式是测量蛋白质内部有序环境产生的局部电场的近乎理想的探针。通过将半胱氨酸残基转化为硫氰酸丙氨酸的简便合成方案,将腈引入三种蛋白质:核糖核酸酶S(RNase S)、人醛糖还原酶(hALR2)和荚膜红细菌的反应中心(RC)。对修饰后的蛋白质进行振动斯塔克效应光谱和傅里叶变换红外光谱分析表明,硫氰酸酯残基是探测蛋白质静电场的一种非常通用的工具。