College of Chemistry, Beijing Normal University, Beijing 100875, China.
Langmuir. 2013 Feb 12;29(6):1956-62. doi: 10.1021/la3048278. Epub 2013 Jan 30.
Erythropoietin (EPO) is an attractive protein-unfolding/folding model because of its high degree of unfolding and folding reversibility and intermediate size. Due to its function for regulating red blood cell production by stimulating late erythroid precursor cells, EPO presents obvious values to biological research. A nonemissive anthracene derivative, that is 9,10-bis[4-(3-sulfonatopropoxyl)-styryl]anthracene sodium salt (BSPSA), with aggregation-induced emission (AIE) charateristics shows a novel phenomenon of AIE when EPO is added. The AIE biosensor for EPO shows the limit of detection is 1 × 10(-9) M. Utilizing the AIE feature of BSPSA, the unfolding process of EPO using guanidine hydrochloride is monitored, which indicates three steps for the folding structures of EPO to transform to random coil. Computational modeling suggests that the BSPSA luminogens prefer docking in the hydrophobic cavity in the EPO folding structures, and the assembly of BSPSA in this cavity makes the AIE available, making the monitoring of unfolding of EPO possible.
促红细胞生成素（EPO）是一种具有吸引力的蛋白质展开/折叠模型，因为它具有高度的展开和折叠可逆性以及中等大小。由于其通过刺激晚期红系前体细胞来调节红细胞生成的功能，EPO 对生物研究具有明显的价值。一种非发光蒽衍生物，即 9,10-双[4-(3-磺丙氧基)苯乙烯基]蒽钠盐（BSPSA），具有聚集诱导发射（AIE）特性，当添加 EPO 时，表现出一种新的 AIE 现象。EPO 的 AIE 生物传感器的检测限为 1×10(-9)M。利用 BSPSA 的 AIE 特性，监测盐酸胍对 EPO 的展开过程，表明 EPO 的折叠结构有三个步骤转化为无规卷曲。计算建模表明，BSPSA 发光体更喜欢停靠在 EPO 折叠结构中的疏水腔中，BSPSA 在该腔中的组装使 AIE 成为可能，从而使 EPO 的展开监测成为可能。
