A model for sedimentation in inhomogeneous media. I. Dynamic density gradients from sedimenting co-solutes
A model for sedimentation in inhomogeneous media. I. Dynamic density gradients from sedimenting co-solutes
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DOI：
10.1016/j.bpc.2003.10.016
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发表时间：
2004-03-01
影响因子：
3.8
通讯作者：
Schuck, P
中科院分区：
文献类型：
--
作者：
Schuck, P
非均匀介质中的大分子沉降具有重要的实际意义。动态密度梯度在分析型超离心中有着悠久的传统，在制备型超离心中也经常使用。本文在考虑局部溶剂密度和黏度时空变化的Lamm方程的有限元解的基础上，提出了一种新的非均匀介质沉积理论模型。它适用于大分子沉降，在存在的动态密度梯度形成的沉淀在一个高浓度的共溶质。在SEDFIT软件中实现了对实验大分子浓度分布的分析。该模型与实测的蛋白质在动态氯化铯梯度下的沉降曲线吻合较好，可以为水化或优先溶剂化参数的影响提供一种测量方法。描述了动态密度梯度中蛋白质沉降的一般特征。(C) 2003, Elsevier B.V.出版
Macromolecular sedimentation in inhomogeneous media is of great practical importance. Dynamic density gradients have a long tradition in analytical ultracentrifugation, and are frequently used in preparative ultracentrifugation. In this paper, a new theoretical model for sedimentation in inhomogeneous media is presented, based on finite element solutions of the Lamm equation with spatial and temporal variation of the local solvent density and viscosity. It is applied to macromolecular sedimentation in the presence of a dynamic density gradient formed by the sedimentation of a co-solute at high concentration. It is implemented in the software SEDFIT for the analysis of experimental macromolecular concentration distributions. The model agrees well with the measured sedimentation profiles of a protein in a dynamic cesium chloride gradient, and may provide a measure for the effects of hydration or preferential solvation parameters. General features of protein sedimentation in dynamic density gradients are described. (C) 2003 Published by Elsevier B.V.