二氧化硫分子通过增强二次成核促进纤维的生长:基于分子动力学的模拟研究

发布时间：2018-03-31 22:18

本文选题：二氧化硫　切入点：淀粉样纤维　出处：《化学学报》2016年08期

【摘要】：空气污染是一种常见的现象.空气污染物是诱发各类疾病的重要因素之一.以二氧化硫分子为代表,研究了它与Aβ17~42原纤维之间的相互作用.伞形抽样模拟表明,二氧化硫分子的引入减少了纤维的解离自由能.分析各氨基酸残基结合二氧化硫的频数得知,二氧化硫分子更容易动态地结合到疏水性氨基酸残基的骨架上,同时也容易结合到带电的氨基酸残基上进而削弱盐桥相互作用,但是对这些相互作用的削弱是非常微小的,不足以破坏原纤维的结构.通过非线性主方程分析,我们发现二氧化硫分子加速了Aβ17~42二次成核过程,同时缩短了迟滞时间而加速纤维的聚集过程.通过这些计算,我们定量地揭示了空气污染物与蛋白质相互作用的特征,期望我们的结果为当今社会评估污染物的健康效应提供宝贵的参考信息.
[Abstract]:Air pollution is a common phenomenon.Air pollutants are one of the important factors inducing various diseases.The interaction between sulfur dioxide and A 尾 17N 42 fiber was studied.The Umbrella sampling simulation shows that the introduction of sulfur dioxide reduces the dissociation free energy of the fiber.By analyzing the frequency of the binding of amino acid residues to sulfur dioxide, it is found that sulfur dioxide molecules are more likely to bind dynamically to the framework of hydrophobic amino acid residues, and at the same time to the charged amino acid residues, thus weakening the salt bridge interaction.But the weakening of these interactions is too small to destroy the fabric of the primary fiber.Through nonlinear master equation analysis, we find that sulfur dioxide accelerates the process of A 尾 17N 42 secondary nucleation and accelerates the fiber aggregation process by shortening the hysteresis time.Through these calculations, we quantitatively reveal the characteristics of the interaction between air pollutants and proteins, and hope that our results will provide valuable reference information for the assessment of the health effects of pollutants in today's society.
【作者单位】：南京大学物理学院;湖北医药学院公共卫生与管理学院;南京大学固体微结构国家重点实验室;南京大学人工微结构科学与技术协同创新中心;
【基金】：国家自然科学基金(Nos.11334004,11174133,81421091) 国家科技部973项目(No.2013CB834100)资助~~
【分类号】：X51;O636.1

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