Department of Chemistry, Faculty of Sciences, Shahid Beheshti University G.C., Evin, Tehran, Iran.
Cell Biochem Biophys. 2011 Mar;59(2):79-88. doi: 10.1007/s12013-010-9116-x.
The nature of protein-sorbitol-water interaction in solution at the molecular level, has been investigated using molecular dynamics simulations. In order to do this task, two molecular dynamics simulations of the protein ADH in solution at room temperature have been carried out, one in the presence (about 0.9 M) and another in the absence of sorbitol. The results show that the sorbitol molecules cluster and move toward the protein, and form hydrogen bonds with protein. Also, coating by sorbitol reduces the conformational fluctuations of the protein compared to the sorbitol-free system. Thus, it is concluded that at moderate concentration of sorbitol solution, sorbitol molecules interact with ADH via many H-bonds that prevent the protein folding. In fact, at more concentrated sorbitol solution, water and sorbitol molecules accumulate around the protein surface and form a continuous space-filling network to reduce the protein flexibility. Namely, in such solution, sorbitol molecules can stabilize a misfolded state of ADH, and prevent the protein from folding to its native structure.
使用分子动力学模拟研究了溶液中蛋白质-山梨糖醇-水相互作用的本质。为了完成这项任务，对室温下存在（约 0.9 M）和不存在山梨糖醇的两种 ADH 蛋白质溶液进行了分子动力学模拟。结果表明，山梨糖醇分子聚集并向蛋白质移动，并与蛋白质形成氢键。此外，与无糖醇体系相比，山梨糖醇的包裹降低了蛋白质的构象波动。因此，可以得出结论，在中等浓度的山梨糖醇溶液中，山梨糖醇分子通过许多氢键与 ADH 相互作用，从而阻止蛋白质折叠。事实上，在更浓的山梨糖醇溶液中，水和山梨糖醇分子聚集在蛋白质表面周围，并形成连续的空间填充网络，以降低蛋白质的柔韧性。也就是说，在这种溶液中，山梨糖醇分子可以稳定 ADH 的错误折叠状态，并阻止蛋白质折叠成其天然结构。
