Effect of Temperature on Topological States of Circular DNA

作     者：Yang-Tao Fan Xiu-Yan Li Yan-Hui Liu Hu Chen 范洋涛;李秀燕;刘艳辉;陈虎

作者机构：College of Physics Guizhou University Guiyang 550025 China Department of Physics Xiamen University Xiamen 361005 China 

出 版 物：《Communications in Theoretical Physics》 (理论物理通讯（英文版）)

年 卷 期：2017年第67卷第7期

页      面：131-136页

核心收录：

学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 0704[理学-天文学] 0702[理学-物理学] 

基　　金：Supported by the National Natural Science Foundation of China under Grant Nos.11047022,11204045,and 11464004 Guizhou Provincial Tracking Key Program of Social Development(SY20123089,SZ20113069) the General Financial Grant from the China Postdoctoral Science Foundation(2014M562341) the Research Foundation for Young University Teachers from Guizhou University(201311) College Innovation Talent Team of Guizhou Province(2014)32 

主　　题：DNA Monte Carlo simulations mechanical properties 

摘      要：The different topological states of circular double-stranded DNA can be defined by their linking number. The equilibrium distribution of linking number can be obtained by circularizing a linear DNA into a circle by ligase. Based on the recent experimental results that the DNA bending rigidity and twist rigidity strongly depend on temperature, the reduced bending rigidity can be approximated by g = （3.19 x10-19 - T. 4.14s10-22） erg. cm over the temperature interval （5 ~ 53） ~ C, and the temperature dependence of twist rigidity can be fitted by C （ T） = （4588.89 exp（-T/117.04）- 251.33） nm. The temperature dependence of the linking number distribution of circular DNAs can be predicted by using Monte Carlo simulation. The variance of linking number distribution on temperature is in accordance with the previous experimental results. Compared with the temperature dependence of bending rigidity, the temperature dependence of twist rigidity causes a noticeable fluctuation in linking number distribution and mainly contribute towards the variance change of linking number distribution of circular DNA. The variance of the writhe number and twist number in the equation （（ALk）21 = （（ATw）2） -b （（Wr）2） depends on the length of circular DNA. When the length of circular DNA is less than 230 nm, the variance of twist number （（ATw）2） is dominant over the variance of writhe number （（（wr）2））whereas for the condition that the length of the circular DNA is larger than 370 nm.