Effects of naturally occurring osmolytes on protein stability and solubility: issues important in protein crystallization
Effects of naturally occurring osmolytes on protein stability and solubility: issues important in protein crystallization
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DOI：
10.1016/j.ymeth.2004.03.022
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发表时间：
2004-11-01
期刊：
影响因子：
4.8
通讯作者：
Bolen, DW
中科院分区：
文献类型：
--
作者：
Bolen, DW
蛋白质的溶解度和稳定性是尝试结晶蛋白质时需要考虑的问题。蛋白质的这两种特性在已经适应水分胁迫条件的生物体细胞中也存在问题，这些条件通常会使某些蛋白质变性或失活。大多数适应环境压力的生物体都是通过产生和积累某些小有机分子（称为渗透剂）来做到这一点的，这些有机分子是通过自然选择产生的，并且能够稳定细胞内蛋白质以抵抗环境压力。在这里，提出了一些概念，以了解天然存在的渗透剂在影响蛋白质稳定性和溶解度方面的特殊性质，以及来自这些化合物研究的原理。除了排除体积和优先相互作用参数之外，疏渗透效应的识别以及通过溶质与侧链的有利相互作用减弱该效应似乎有助于保护渗透剂对蛋白质稳定性和溶解度的全套影响。考虑到这些概念以及尿素与肽主链有利地相互作用的事实，我们注意到：（1）渗透剂诱导的对蛋白质稳定性的影响（从变性到迫使蛋白质折叠）可以通过实验实现，并且在近分子水平细节上理解基本原理，（2）渗透剂介导的溶解度影响（从蛋白质沉淀到蛋白质溶解）是基于这些原理可预测的。将这些效果与 2-甲基-2,4-戊二醇和聚乙二醇对蛋白质的效果进行对比，以及如何将天然存在的渗透剂的原理应用于这两种常用的蛋白质结晶剂。 (C) 2004 Elsevier Inc. 保留所有权利。
Protein solubility and stability are issues of consideration in attempts to crystallize proteins. These two properties of proteins are also at issue in the cells of organisms that have adapted to water stress conditions that could ordinarily denature or inactivate some proteins. Most organisms that have adapted to environmental stresses have done so by production and accumulation of certain small organic molecules, known as osmolytes, that arose by natural selection and have the ability to stabilize intracellular proteins against the environmental stress. Here, concepts developed to understand the special properties of the naturally occurring osmolytes in effecting protein stability and solubility, and the principles that have come from studies of these compounds have been presented. Along with excluded volume and preferential interaction parameters, identification of the osmophobic effect and the attenuation of this effect by favorable interactions of solute with side-chains appear to contribute to the full set of effects protecting osmolytes have on protein stability and solubility. With these concepts in mind and the fact that urea interacts favorably with the peptide backbone we note that: (1) osmolyte-induced effects on protein stability ranging from denaturation to forcing proteins to fold can be achieved experimentally and the underlying principles understood at near molecular-level detail, and (2) osmolyte-mediated solubility effects ranging from protein precipitation to protein solubilization are predictable based on these principles. These effects are contrasted and compared with effects of 2-methyl-2,4-pentanediol and polyethylene glycol on proteins, and how the principles found for the naturally occurring osmolytes can be applied to these two commonly used protein crystallizing agents. (C) 2004 Elsevier Inc. All rights reserved.