Departamento de Química Física, Facultad de Química, Universidad de Murcia, Murcia, Spain.
Macromol Biosci. 2010 Jul 7;10(7):721-30. doi: 10.1002/mabi.200900464.
The calculation of solution properties of flexible macromolecules and other nanoparticles requires, in addition to the hydrodynamic formalisms needed for the sedimentation coefficient and other transport properties, the consideration of the conformational statistics and internal dynamics. The latter aspects can be handled with simulation methods like Monte Carlo and Brownian dynamics. An example of a Monte Carlo simulation for a model specific of DNA is illustrated with results for the several solution properties over an extremely wide range of molecular weight. The convenience of having computational tools of a quite general applicability has prompted us to implement the simulation and hydrodynamic treatments in software packages, MONTEHYDRO for Monte Carlo, and SIMUFLEX for Brownian dynamics which-with a scope similar to the HYDRO suite for rigid particles-can handle a variety of situations. As an application of the new methodology to a yet unclear problem in analytical ultracentrifugation, in a simple application of the SIMUFLEX software, we present a simulation of the so-called anomalous sedimentation of very long DNA molecules, obtaining results for the experimentally observable rotor-speed-dependence of the sedimentation coefficient.
除了沉降系数和其他输运性质所需的流体动力形式外,柔性大分子和其他纳米粒子溶液性质的计算还需要考虑构象统计和内部动力学。这些方面可以用模拟方法来处理,如蒙特卡罗和布朗动力学。本文以 DNA 模型的蒙特卡罗模拟为例,说明了在极其广泛的分子量范围内的几种溶液性质的结果。具有相当普遍适用性的计算工具的便利性促使我们在软件包中实现模拟和流体力学处理,MONTEHYDRO 用于蒙特卡罗,SIMUFLEX 用于布朗动力学,其范围与刚性粒子的 HYDRO 套件相似,可以处理各种情况。作为对分析超速离心中一个尚未明确问题的新方法的应用,我们在 SIMUFLEX 软件的一个简单应用中,模拟了非常长的 DNA 分子的所谓异常沉降,得到了实验可观察到的沉降系数随转子转速的变化的结果。