Prakash Shikha, Singh Yashwant
Department of Physics, Banaras Hindu University, Varanasi-221 005, India.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Sep;84(3 Pt 1):031905. doi: 10.1103/PhysRevE.84.031905. Epub 2011 Sep 6.
We use a simple nonlinear scaler displacement model to calculate the distribution of effects created by a shear stress on a double-stranded DNA (dsDNA) molecule and the value of shear force F(c) that is required to separate the two strands of a molecule at a given temperature. It is shown that for molecules of base pairs fewer than than 21, the entire single strand moves in the direction of applied force, whereas for molecules having base pairs more than 21, part of the strand moves in the opposite direction under the influence of force acting on the other strand. This result as well as the calculated values of F(c) as a function of length of dsDNA molecules are in very good agreement with the experimental values of Hatch et al. [Phys. Rev. E 78, 011920 (2008)].
我们使用一个简单的非线性标量位移模型来计算剪切应力对双链DNA(dsDNA)分子产生的效应分布,以及在给定温度下分离分子两条链所需的剪切力F(c)的值。结果表明,对于碱基对少于21个的分子,整个单链沿作用力方向移动,而对于碱基对多于21个的分子,在作用于另一条链的力的影响下,部分链会沿相反方向移动。这一结果以及作为dsDNA分子长度函数的F(c)计算值与哈奇等人[《物理评论E》78, 011920 (2008)]的实验值非常吻合。