Department of Cellular and Molecular Biology, Faculty of Science, Azarbaijan University of Tarbiat Moallem, Tabriz, Iran.
J Chem Phys. 2011 Jan 21;134(3):035104. doi: 10.1063/1.3530072.
Co-solvents such as glycerol and sorbitol are small organic molecules solvated in the cellular solutions that can have profound effects on the protein structures. Here, the molecular dynamics simulations and comparative structural analysis of magainin, as a peptide model, in pure water, 2,2,2-trifluoroethanol∕water, glycerol∕water, and sorbitol∕water are reported. Our results show that the peptide NMR structure is largely maintained its native structure in osmolytes-water mixtures. The simulation data indicates that the stabilizing effect of glycerol and sorbitol is induced by preferential accumulation of glycerol and sorbitol molecules around the nonpolar and aromatic residues. Thus, the presence of glycerol and sorbitol molecules decreases the interactions of water molecules with the hydrophobic residues of the peptide, and the alpha helical structure is stabilized.
共溶剂如甘油和山梨醇是溶解在细胞溶液中的小分子有机分子，它们对蛋白质结构有深远的影响。在这里，我们报告了抗菌肽 magainin 的分子动力学模拟和比较结构分析，它是一个肽模型，在纯水中、2,2,2-三氟乙醇/水、甘油/水和山梨醇/水中的结构。我们的结果表明，在渗透剂-水混合物中，肽的 NMR 结构在很大程度上保持其天然结构。模拟数据表明，甘油和山梨醇的稳定作用是由甘油和山梨醇分子优先积累在非极性和芳香残基周围引起的。因此，甘油和山梨醇分子的存在减少了水分子与肽的疏水性残基的相互作用，稳定了α螺旋结构。
