中国物理B ›› 2010, Vol. 19 ›› Issue (8): 88701-088701.doi: 10.1088/1674-1056/19/8/088701

• CROSS DISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Effect of electrolyte concentration on DNA A–B conformational transition:An unrestrained molecular dynamics simulation study

藤本晋太郎, 于养信   

  1. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • 收稿日期:2009-10-05 修回日期:2009-12-23 出版日期:2010-08-15 发布日期:2010-08-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 20876083 and 20736003) and Specialized Research Fund for the Doctorial Program of Higher Education of China (Grant No. 2007003009).

Effect of electrolyte concentration on DNA A–B conformational transition:An unrestrained molecular dynamics simulation study

Shintaro Fujimoto(藤本晋太郎) and Yu Yang-Xin(于养信)   

  1. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • Received:2009-10-05 Revised:2009-12-23 Online:2010-08-15 Published:2010-08-15
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 20876083 and 20736003) and Specialized Research Fund for the Doctorial Program of Higher Education of China (Grant No. 2007003009).

摘要: The DNA conformational transition depends on both the DNA sequences and environment such as solvent as well as electrolyte in the solution. This paper uses the AMBER8 package to investigate the electrolyte concentration influence on the dynamics of the A→B conformational transition of DNA duplex d(CGCGAATTCGCG)2. The results from the restrained molecular dynamics (MD) simulations indicate that the total energies of the systems for A--DNA are always higher than those for B--DNA, and that the A→B conformational transition in aqueous NaCl solution is a downhill process. The results from the unrestrained MD simulations, as judged by the average distance between the C5' atoms (average helical rise per ten base pair), show that the concentrated NaCl solution slows down the A→B conformational transition. This observation can be well understood by analyses of the difference between the counterion distributions around A--DNA and B--DNA.

Abstract: The DNA conformational transition depends on both the DNA sequences and environment such as solvent as well as electrolyte in the solution. This paper uses the AMBER8 package to investigate the electrolyte concentration influence on the dynamics of the A→B conformational transition of DNA duplex d(CGCGAATTCGCG)2. The results from the restrained molecular dynamics (MD) simulations indicate that the total energies of the systems for A–DNA are always higher than those for B–DNA, and that the A→B conformational transition in aqueous NaCl solution is a downhill process. The results from the unrestrained MD simulations, as judged by the average distance between the C5' atoms (average helical rise per ten base pair), show that the concentrated NaCl solution slows down the A→B conformational transition. This observation can be well understood by analyses of the difference between the counterion distributions around A–DNA and B–DNA.

Key words: molecular dynamics simulation, nucleic acid, conformational transition, electrolyte

中图分类号:  (Dynamics of biomolecules)

  • 87.15.H-
87.14.G- (Nucleic acids) 87.15.A- (Theory, modeling, and computer simulation) 87.15.B- (Structure of biomolecules) 87.15.Cc (Folding: thermodynamics, statistical mechanics, models, and pathways) 87.15.N- (Properties of solutions of macromolecules)