以牛血清白蛋白(BSA)作为模型蛋白,通过浊度法研究BSA形成的无序蛋白聚集体的分解动力学并揭示其复杂结构细节.实验发现,BSA无序聚集体在碱性条件下分解过程有4个动力学阶段,包括1个快速的分解阶段,2个相对较慢的分解阶段和1个动力学惰性阶段.由此推测BSA聚集体中至少含有4种不同的BSA单体形态.
Protein aggregation is not only a common problem in biopharmaceutical industry involving protein drugs,but also a devastating phenomenon closely linked to numerous human diseases.Understanding structural details of protein aggregates is fundamentally important in the prediction and prevention of protein aggregation behavior.In this study,we explore to use a turbidity-based dissociation kinetic assay to tackle the complex nature of protein amorphous aggregates by a model protein,bovine serum albumin(BSA).We observe that the dissociation of BSA aggregates under basic condition consists of four distinct kinetic phases,including a burst phase,two relatively slow phases,and one kinetically inert phase.Such kinetic observation allows us to hypothesize that BSA aggregates consist of at least four different types of BSA monomeric structures at the molecular level.To the best of our knowledge,this is the first turbidity-based investigation with the aim to elucidate the structural heterogeneity of protein amorphous aggregates.
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