Chen Yuhao, Yu Wancheng, Wang Jiajun, Luo Kaifu
CAS Key Laboratory of Soft Matter Chemistry, Collaborative Innovation Center of Chemistry for Energy Materials, and Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui Province 230026, People's Republic of China.
J Chem Phys. 2015 Oct 7;143(13):134904. doi: 10.1063/1.4932370.
Entropy driven polymer segregation in confinements as a model for chromosome separation in bacteria has attracted wide attention; however, the effects of macromolecular crowding and the interaction between the binding protein and the newly replicated DNA on the segregation dynamics are not clear. Using Langevin dynamics simulations, we investigate the influences of crowders and the attractive interaction between the polymer and a small number of crowders on segregation of two overlapping polymers under a cylindrical confinement. We find that the segregation time increases with increasing the volume fraction of crowders due to the slower chain diffusion in crowded environments. For a fixed volume fraction of crowders, the segregation time decreases with increasing the size of crowders. Moreover, the attractive interaction between the polymer and a small number of crowders can significantly facilitate the chain segregation. These results are important for understanding the chromosome segregation in living cells.
作为细菌中染色体分离模型的受限空间内熵驱动聚合物分离已引起广泛关注;然而,大分子拥挤效应以及结合蛋白与新复制DNA之间的相互作用对分离动力学的影响尚不清楚。我们使用朗之万动力学模拟,研究了拥挤剂以及聚合物与少量拥挤剂之间的吸引相互作用对圆柱受限空间内两条重叠聚合物分离的影响。我们发现,由于在拥挤环境中链扩散较慢,分离时间随拥挤剂体积分数的增加而增加。对于固定的拥挤剂体积分数,分离时间随拥挤剂尺寸的增加而减少。此外,聚合物与少量拥挤剂之间的吸引相互作用可显著促进链分离。这些结果对于理解活细胞中的染色体分离具有重要意义。