蛋白淀粉样纤维与多种疾病有关,如阿尔茨海默病、帕金森病、Ⅱ型糖尿病等.荧光染料硫代黄素T(ThT)广泛地应用于淀粉样纤维的定性和定量测定.但从目前的研究来看,ThT与淀粉样纤维结合的动力学机理研究尚非常少见.本研究应用荧光停流动力学技术对盐酸胍诱导的溶菌酶淀粉样纤维和ThT的结合动力学进行了研究,提出ThT与溶菌酶淀粉样纤维结合的动力学符合双位点平行反应机理模型.本研究对深入理解荧光染料分子与蛋白淀粉样纤维的作用有借鉴意义.
Deposition of amyloid fibrils in tissues and organs is relevant to a wide range of devastating human diseases, including Alzheimer’s disease, Parkinson’s disease, and type Ⅱ diabetes. Thioflavin T(ThT)is widely used as a fluorescent probe for qualitative and quantitative detections of amyloid fibrils. Yet the exact kinetic mechanism of ThT binding onto amyloid fibril remains elusive. In this study, we used fluorescence-detected stopped-flow technique to study the binding mechanism of ThT onto the amyloid fibril of hen egg white lysozyme induced by guanidine hydrochloride. We proposed a kinetic binding mechanism to interpret our experimental observations. Our results showed that the binding of ThT onto lysozyme fibril follow a dual-site parallel binding mechanism. We believe our work is beneficial for better understanding of the interaction between fluorescent dye and amyloid fibril.
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