Acta Chim. Sinica ›› 2016, Vol. 74 ›› Issue (8): 694-702.DOI: 10.6023/A16050216 Previous Articles    

Article

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

康文斌a,b,c, 夏耘a,c, 王骏a,c,d, 王炜a,c,d   

  1. a 南京大学 物理学院 南京 210093;
    b 湖北医药学院 公共卫生与管理学院 十堰 442000;
    c 南京大学 固体微结构国家重点实验室 南京 210093;
    d 南京大学 人工微结构科学与技术协同创新中心 南京 210093
  • 投稿日期:2016-05-03 发布日期:2016-08-10
  • 通讯作者: 康文斌, 王骏, 王炜 E-mail:wbkang@hbmu.edu.cn;wangj@nju.edu.cn;wangwei@nju.edu.cn
  • 基金资助:

    项目受国家自然科学基金(Nos. 11334004,11174133,81421091)和国家科技部973项目(No. 2013CB834100)资助.

Sulfur Dioxide Promotes the Formation of Amyloid Fibrils through Enhanced Secondary Nucleation: A Molecular Dynamics Study

Kang Wenbina,b,c, Xia Yuna,c, Wang Juna,c,d, Wang Weia,c,d   

  1. a School of Physics, Nanjing University, Nanjing 210093, China;
    b School of Public Health and Management, Hubei University of Medicine, Shiyan 442000, China;
    c National Laboratory of Solid State Microstructure, Nanjing University, Nanjing 210093, China;
    d Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
  • Received:2016-05-03 Published:2016-08-10
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 11334004, 11174133, 81421091) and the National Basic Research Program of China (No. 2013CB834100).

Air pollution is a common phenomenon in developing countries, and pollutants are suggested to be essential reasons to produce various diseases, such as cancers, neuro-degenerative diseases and so on. In present work, the effects of sulfur dioxide on the dissociation of Aβ17~42 peptides from core region of Aβ fibril were studied with umbrella sampling method. It is found that the free energy penalty related to the dissociation processes would decrease for larger concentrations of sulfur dioxide. The detailed interactions between peptides and sulfur dioxide are analyzed based on contact statistics. It is suggested that the destabilization of the Aβ fibril is realized by the binding of sulfur dioxide with the peptide backbone as well as the side chains of charged residues, which results in the decrease of hydrophobic interaction and blockage of the electrostatic interactions between charged residues. Furthermore, the positive contribution of such a marginal destabilization on the growth of fibril is also discussed with a nonlinear master equation, which is consistent with the medical knowledge. Through these computations, we disclose the characteristics of the interactions between air pollutants and protein molecules. We expect that these results could help to assess the effect of air pollutants on human health.

Key words: sulfur dioxide, amyloid fibril, molecular dynamic simulation, dissociation free energy, secondary nucleation