DNA在熵受限管道中穿越过程的计算机模拟

利用Metropolis Monte-Carlo动力学方法结合键长涨落算法，模拟了单链DNA分子在电场作用下穿越熵受限管道的动力学过程.结果表明，DNA分子穿越管道时将经历无规迁移、受限迁移及快速迁移等几个显著不同的阶段.平均迁移率随外场增加而增大并最终达到饱和值μ0，受限时间的对数与所加场强的倒数之间基本满足线性关系.模拟结果不仅与文献所给的实验结果基本一致，而且还可以提供实验不能直接观察到的DNA分子较为详细的穿越过程.

Simulation of translocation of long DNA chain through an entropic trapping channel

Metropolis molecular dynamics simulation combined with bond-fluctuation method was employed to study the dynamic process of single DNA chain through an entropic trapping channel driven by an electric field. It was found that the single DNA chain experienced the processes such as random transfer, entropic trapping and fast transfer etc. The mobility of DNA increased with the increase of electric field and reached the conformation-independent mobility μ0 at a high electric field. In particular, a clear linear relationship between lnτ and 1/Eav (the reciprocal of electric field) could be seen. The simulation result was in agreement with the experimental result presented by Han et al qualitatively. In addition, the simulation provided a detailed dynamic process of the single DNA chain driven through an entropic trapping channel,which could not be observed in the experiment.