Zhou Zicong, Joós Béla
Department of Physics and Graduate Institute of Life Sciences, Tamkang University, 151 Ying-chuan, Tamsui, Taiwan, Republic of China.
Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Jun;77(6 Pt 1):061906. doi: 10.1103/PhysRevE.77.061906. Epub 2008 Jun 9.
Using a path integral technique, we show exactly that for a semiflexible biopolymer in constant extension ensemble, no matter how long the polymer and how large the external force, the effects of short-range correlations in the sequence-dependent spontaneous curvatures and torsions can be incorporated into a model with well-defined mean spontaneous curvature and torsion as well as a renormalized persistence length. Moreover, for a long biopolymer with large mean persistence length, the sequence-dependent persistence lengths can be replaced by their mean. However, for a short biopolymer or for a biopolymer with small persistence lengths, inhomogeneity in persistence lengths tends to make physical observables very sensitive to details and therefore less predictable.
利用路径积分技术，我们精确地表明，对于处于恒定伸长系综中的半柔性生物聚合物，无论聚合物多长以及外力多大，序列相关的自发曲率和扭转中的短程关联效应都可以纳入一个具有明确定义的平均自发曲率和扭转以及重整化持久长度的模型中。此外，对于具有大平均持久长度的长生物聚合物，序列相关的持久长度可以用它们的平均值来代替。然而，对于短生物聚合物或具有小持久长度的生物聚合物，持久长度的不均匀性往往会使物理可观测量对细节非常敏感，因此预测性较差。
