Beynon L M, Dutton G G, Richards J C
Department of Chemistry, University of British Columbia, Vancouver, Canada.
Carbohydr Res. 1990 Sep 19;205:347-59. doi: 10.1016/0008-6215(90)80152-s.
The structure of the capsular antigen of E. coli K49 and the oligosaccharides derived from it by partial acid hydrolysis were studied by 1D- and 2D-n.m.r. spectroscopy, g.l.c.-c.i.-mass spectrometry, and methylation analysis. The K49 polysaccharide consists of the repeating unit----4)-beta-D-GlcpA-(1----6)-beta-D-Galp-(1----6)-beta-D-Glcp- (1----3)-beta - D-GalpNAc-(1----. The glucuronic acid residues are substituted, in the apparent molar ratio of 4:1, with L-threonine and L-serine linked amidically to the carboxyl group.
通过一维和二维核磁共振光谱、气相色谱-化学电离-质谱分析以及甲基化分析，对大肠杆菌K49荚膜抗原的结构及其经部分酸水解得到的寡糖进行了研究。K49多糖由重复单元----4)-β-D-葡萄糖醛酸-(1----6)-β-D-半乳糖-(1----6)-β-D-葡萄糖-(1----3)-β-D-氨基半乳糖-(1----组成。葡萄糖醛酸残基以4:1的表观摩尔比被L-苏氨酸和L-丝氨酸取代，它们通过酰胺键与羧基相连。
