Processes of DNA condensation induced by multivalent cations: Approximate annealing experiments and molecular dynamics simulations  

作　　者：柴爱华 冉诗勇 张冬 蒋杨伟 杨光参 章林溪 

机构地区：[1]Department of Physics,Zhejiang University [2]College of Mathematics,Physics and Information Engineering,Jiaxing University [3]Department of Physics,Wenzhou University

出　　处：《Chinese Physics B》2013年第9期648-655,共8页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 20974081, 20934004, 21174131, and 21104060);the Zhejiang Provincial Natural Science Foundation of China (Grant No. Y4110357)

摘　　要：The condensation of DNA induced by spermine is studied by atomic force microscopy （AFM） and molecular dynamics （MD） simulation in this paper. In our experiments, an equivalent amount of multivalent cations is added to the DNA solutions in different numbers of steps, and we find that the process of DNA condensation strongly depends on the speed of adding cations. That is, the slower the spermine cations are added, the slower the DNA aggregates. The MD and steered molecular dynamics （SMD） simulation results agree well with the experimental results, and the simulation data also show that the more steps of adding multivalent cations there are, the more compact the condensed DNA structure will be. This investigation can help us to control DNA condensation and understand the complicated structures of DNA--cation complexes.The condensation of DNA induced by spermine is studied by atomic force microscopy （AFM） and molecular dynamics （MD） simulation in this paper. In our experiments, an equivalent amount of multivalent cations is added to the DNA solutions in different numbers of steps, and we find that the process of DNA condensation strongly depends on the speed of adding cations. That is, the slower the spermine cations are added, the slower the DNA aggregates. The MD and steered molecular dynamics （SMD） simulation results agree well with the experimental results, and the simulation data also show that the more steps of adding multivalent cations there are, the more compact the condensed DNA structure will be. This investigation can help us to control DNA condensation and understand the complicated structures of DNA--cation complexes.

关 键 词：DNA condensation multivalent cations molecular dynamics simulation 

分 类 号：O561[理学—原子与分子物理]