Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
Protein Sci. 2010 Apr;19(4):888-92. doi: 10.1002/pro.336.
Unlike most proteins, which are in equilibrium with partially and globally unfolded conformations, kinetically stable proteins (KSPs) are trapped in their native conformations and are often resistant to harsh environment. Based on a previous correlation between kinetic stability (KS) and a protein's resistance to sodium dodecyl sulfate (SDS), we show here a simple method to identify KSPs by SDS-capillary electrophoresis (CE). Control non-KSPs were fully denatured by SDS and formed protein:SDS complexes that exhibited similar mobility in CE. In contrast, KSPs bound fewer SDS molecules, and showed a very different migration time and peak pattern in CE, thereby providing some insight about the structural heterogeneity of SDS:protein complexes and the relative KS of the various proteins.
与大多数处于部分展开和整体展开构象平衡的蛋白质不同,动力学稳定的蛋白质(KSP)被锁定在其天然构象中,并且通常能抵抗恶劣的环境。基于先前动力学稳定性(KS)与蛋白质对十二烷基硫酸钠(SDS)的抗性之间的相关性,我们在此展示了一种通过 SDS-毛细管电泳(CE)鉴定 KSP 的简单方法。对照非 KSP 被 SDS 完全变性,并形成 SDS 与蛋白质的复合物,在 CE 中表现出相似的迁移率。相比之下,KSP 与较少的 SDS 分子结合,在 CE 中表现出非常不同的迁移时间和峰型模式,从而提供了关于 SDS-蛋白质复合物的结构异质性和各种蛋白质的相对 KS 的一些见解。