中国物理B ›› 2017, Vol. 26 ›› Issue (12): 128701-128701.doi: 10.1088/1674-1056/26/12/128701

所属专题: SPECIAL TOPIC — Soft matter and biological physics

• SPECIAL TOPIC—Soft matter and biological physics • 上一篇    下一篇

Anisotropic formation mechanism and nanomechanics for the self-assembly process of cross-β peptides

Li Deng(邓礼), Yurong Zhao(赵玉荣), Peng Zhou(周鹏), Hai Xu(徐海), Yanting Wang(王延颋)   

  1. 1. Center for Bioengineering and Biotechnology, China University of Petroleum(East China), Qingdao 266580 China;
    2. CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences(CAS), Beijing 100190 China;
    3. School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
  • 收稿日期:2017-08-10 修回日期:2017-09-18 出版日期:2017-12-05 发布日期:2017-12-05
  • 通讯作者: Yanting Wang E-mail:wangyt@itp.ac.cn
  • 基金资助:

    Project supported by the National Basic Research Program of China (Grant No. 2013CB932804), the National Natural Science Foundation of China (Grant Nos. 11421063, 11647601, 11504431, and 21503275), the Scientific Research Foundation of China University of Petroleum (East China) for Young Scholar (Grant Y1304073). Yanting Wang also thanks the financial support through the CAS Biophysics Interdisciplinary Innovation Team Project (Grant No. 2060299).

Anisotropic formation mechanism and nanomechanics for the self-assembly process of cross-β peptides

Li Deng(邓礼)1, Yurong Zhao(赵玉荣)1, Peng Zhou(周鹏)1, Hai Xu(徐海)1, Yanting Wang(王延颋)2,3   

  1. 1. Center for Bioengineering and Biotechnology, China University of Petroleum(East China), Qingdao 266580 China;
    2. CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences(CAS), Beijing 100190 China;
    3. School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2017-08-10 Revised:2017-09-18 Online:2017-12-05 Published:2017-12-05
  • Contact: Yanting Wang E-mail:wangyt@itp.ac.cn
  • Supported by:

    Project supported by the National Basic Research Program of China (Grant No. 2013CB932804), the National Natural Science Foundation of China (Grant Nos. 11421063, 11647601, 11504431, and 21503275), the Scientific Research Foundation of China University of Petroleum (East China) for Young Scholar (Grant Y1304073). Yanting Wang also thanks the financial support through the CAS Biophysics Interdisciplinary Innovation Team Project (Grant No. 2060299).

摘要:

Nanostructures self-assembled by cross-β peptides with ordered structures and advantageous mechanical properties have many potential applications in biomaterials and nanotechnologies. Quantifying the intra-and inter-molecular driving forces for peptide self-assembly at the atomistic level is essential for understanding the formation mechanism and nanomechanics of various morphologies of self-assembled peptides. We investigate the thermodynamics of the intra-and inter-sheet structure formations in the self-assembly process of cross-β peptide KⅢIK by means of steered molecular dynamics simulation combined with umbrella sampling. It is found that the mechanical properties of the intra-and inter-sheet structures are highly anisotropic with their intermolecular bond stiffness at the temperature of 300 K being 5.58 N/m and 0.32 N/m, respectively. This mechanical anisotropy comes from the fact that the intra-sheet structure is stabilized by enthalpy but the inter-sheet structure is stabilized by entropy. Moreover, the formation process of KⅢIK intra-sheet structure is cooperatively driven by the van der Waals (VDW) interaction between the hydrophobic side chains and the electrostatic interaction between the hydrophilic backbones, but that of the inter-sheet structure is primarily driven by the VDW interaction between the hydrophobic side chains. Although only peptide KⅢIK is studied, the qualitative conclusions on the formation mechanism should also apply to other cross-β peptides.

关键词: molecular dynamics simulation, peptide self-assembly, intermolecular force, thermodynamics

Abstract:

Nanostructures self-assembled by cross-β peptides with ordered structures and advantageous mechanical properties have many potential applications in biomaterials and nanotechnologies. Quantifying the intra-and inter-molecular driving forces for peptide self-assembly at the atomistic level is essential for understanding the formation mechanism and nanomechanics of various morphologies of self-assembled peptides. We investigate the thermodynamics of the intra-and inter-sheet structure formations in the self-assembly process of cross-β peptide KⅢIK by means of steered molecular dynamics simulation combined with umbrella sampling. It is found that the mechanical properties of the intra-and inter-sheet structures are highly anisotropic with their intermolecular bond stiffness at the temperature of 300 K being 5.58 N/m and 0.32 N/m, respectively. This mechanical anisotropy comes from the fact that the intra-sheet structure is stabilized by enthalpy but the inter-sheet structure is stabilized by entropy. Moreover, the formation process of KⅢIK intra-sheet structure is cooperatively driven by the van der Waals (VDW) interaction between the hydrophobic side chains and the electrostatic interaction between the hydrophilic backbones, but that of the inter-sheet structure is primarily driven by the VDW interaction between the hydrophobic side chains. Although only peptide KⅢIK is studied, the qualitative conclusions on the formation mechanism should also apply to other cross-β peptides.

Key words: molecular dynamics simulation, peptide self-assembly, intermolecular force, thermodynamics

中图分类号:  (Peptides)

  • 87.14.ef
87.10.Tf (Molecular dynamics simulation)