Statistical mechanics of a double-stranded rod model for DNA melting and elasticity
Statistical mechanics of a double-stranded rod model for DNA melting and elasticity
复制标题
DNA 熔解和弹性双链棒模型的统计力学
DOI：
10.1039/d0sm00521e
复制
发表时间：
2020
期刊：
影响因子：
3.4
通讯作者：
Purohit, Prashant K.
中科院分区：
文献类型：
--
作者：
Singh, Jaspreet;Purohit, Prashant K.
在室温下观察到的DNA分子的双螺旋拓扑结构，在没有任何外部负载的情况下，可以通过增加浴温或施加拉伸力来破坏，导致称为DNA熔化的自发链分离。本文将二维双链分子的连续介质力学与统计力学相结合，形成了研究双链分子热熔解和张力熔解的统一框架：它预测了熔融温度随拉伸载荷的变化，提供了基于力学的理解在熔融转变中观察到的协同性，并揭示了溶液静电和DNA微力学变形之间的相互作用，这种变形表现为随着离子浓度的增加而熔化温度的增加。这个新颖的预测框架揭示了DNA融化的微观力学方面，并预测了实验观察到的趋势或使用克莱佩龙方程提取的现象学。
The double-helical topology of DNA molecules observed at room temperature in the absence of any external loads can be disrupted by increasing the bath temperature or by applying tensile forces, leading to spontaneous strand separation known as DNA melting. Here, continuum mechanics of a 2D birod is combined with statistical mechanics to formulate a unified framework for studying both thermal melting and tensile force induced melting of double-stranded molecules: it predicts the variation of melting temperature with tensile load, provides a mechanics-based understanding of the cooperativity observed in melting transitions, and reveals an interplay between solution electrostatics and micromechanical deformations of DNA which manifests itself as an increase in the melting temperature with increasing ion concentration. This novel predictive framework sheds light on the micromechanical aspects of DNA melting and predicts trends that were observed experimentally or extracted phenomenologically using the Clayperon equation.