Non-Markovian polymer reaction kinetics
Non-Markovian polymer reaction kinetics
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DOI：
10.1038/nchem.1378
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发表时间：
2012-07-01
期刊：
影响因子：
21.8
通讯作者：
Voituriez, R.
中科院分区：
文献类型：
--
作者：
Guerin, T.;Benichou, O.;Voituriez, R.
描述聚合物反应的动力学，例如核酸或多肽中的环和发夹的形成，由于其链的结构动力学而变得复杂。尽管分子内反应（如环化）和分子间反应已经被广泛地研究，无论是实验还是理论上，到目前为止，还没有对运输受限的聚合物反应动力学进行精确明确的分析处理，即使是在由线性弹簧连接的最简单的单体（劳斯）模型的情况下。我们介绍了一种新的分析方法来计算聚合物反应的平均反应时间，包括单体运动的非马尔可夫动力学。这就要求在反应的瞬间确定聚合物的构象统计数据，作为副产品，它提供了关于反应路径的新信息。我们发现聚合物的典型反应构象比平衡构象更延伸，这导致反应时间明显短于现有的经典马尔可夫理论预测。
Describing the kinetics of polymer reactions, such as the formation of loops and hairpins in nucleic acids or polypeptides, is complicated by the structural dynamics of their chains. Although both intramolecular reactions, such as cyclization, and intermolecular reactions have been studied extensively, both experimentally and theoretically, there is to date no exact explicit analytical treatment of transport-limited polymer reaction kinetics, even in the case of the simplest (Rouse) model of monomers connected by linear springs. We introduce a new analytical approach to calculate the mean reaction time of polymer reactions that encompasses the non-Markovian dynamics of monomer motion. This requires that the conformational statistics of the polymer at the very instant of reaction be determined, which provides, as a by-product, new information on the reaction path. We show that the typical reactive conformation of the polymer is more extended than the equilibrium conformation, which leads to reaction times significantly shorter than predicted by the existing classical Markovian theory.