Studies on the conformational flexibility of α-l-rhamnose-containing oligosaccharides using 13C-site-specific labeling, NMR spectroscopy and molecular simulations: implications for the three-dimensional structure of bacterial rhamnan polysaccharides
作者:K. Hanna M. Jonsson、Elin Säwén、Göran Widmalm
DOI:10.1039/c2ob06924e
日期:——
together with total line-shape analysis were used to extract conformationally dependent hetero- and homonuclear spin–spin coupling constants. This resulted in the determination of 2JC2′,H1′, 3JC1′,C1, 3JC1′,C3, 3JC2′,C2, 2JC1′,C2, 1JC1′,C2′, and 1JC1′,H1′. These data together with previously determined JCH and 1H,1H NOEs result in fourteen conformationally dependent NMR parameters that are available
细菌多糖由多种单糖组成, 大号鼠李糖 (6-脱氧-L-甘露糖)成为其中的一员。这种糖经常是α-的一部分(1→2) -和/或α-(1→3) -键,所以我们研究了二糖α-大号-RHA p - (1→2)-α-大号- Rha p -OMe可在此糖苷键上获得构象偏好信息。目标二糖用合成13在C1'和C2在'C位点特异性标记,我。例如,在终端组中。2D 1 H,13 C-HSQC-HECADE和1 H,13 C-J-HMBC NMR实验,1D 13 C和11 H NMR光谱和总的线形分析用于提取构象相关的异核和同核自旋-自旋偶合常数。这导致的判断2 Ĵ C2',H1' ,3 Ĵ C1',C1,3 Ĵ C1',C3,3 Ĵ C2',C2,2 Ĵ C1',C2,1 Ĵ C1',C2' ,和1 J C1',H1'。这些数据与先前确定的J CH和1 H,1H NOEs产生14个构象相关的NMR参数,可用于分析糖苷键的柔性和构象偏好。二糖的100