Conformational Effects of the Non-natural α-Methylserine on Small Peptides and Glycopeptides
作者:Alberto Fernández-Tejada、Francisco Corzana、Jesús H. Busto、Alberto Avenoza、Jesús M. Peregrina
DOI:10.1021/jo901988w
日期:2009.12.18
different effect on the backbone of the peptide derived from Thr and MeSer. In the former, the β-O-glycosylation is responsible for the experimentally observed shift from extended conformations (peptide) to folded ones (glycopeptide). In contrast, the β-O-glycosylation of the MeSer-containing peptide, which clearly shows two main conformations in aqueous solution [extended ones (70%) and β-turn (30%)]
报道了含有苏氨酸-丙氨酸-丙氨酸序列(Thr-Ala-Ala)的肽和糖肽在水溶液中的合成和构象分析。此外,苏氨酸残基已被季氨基酸α-甲基丝氨酸(MeSer)取代,并且还研究了其相应的非天然肽和糖肽。水溶液中的构象分析将NOE和耦合常数数据与带有时间平均约束的Molecular Dynamics(MD)模拟相结合。该研究表明,β- O-糖基化对衍生自Thr和MeSer的肽的骨架产生了显着且完全不同的作用。在前者中,β- O-糖基化是实验观察到的从延伸构象(肽)到折叠构象(糖肽)的转变的原因。相反,含MeSer的肽的β- O-糖基化,清楚地显示出水溶液中的两个主要构象[扩展构象(70%)和β-转角(30%)],从而导致了高度的灵活性。骨干。