Dutton G G, Kuma-Mintah A, Parolis H
Department of Chemistry, University of British Columbia, Vancouver, Canada.
Carbohydr Res. 1990 Mar 25;197:171-80. doi: 10.1016/0008-6215(90)84139-l.
The capsular polysaccharide of Escherichia coli K31 has been found by methylation analysis and n.m.r. spectroscopy to be based on the hexasaccharide shown. The sequence of the repeating unit was deduced from the combined results of beta-elimination, lithium-ethylenediamine degradation, and hydrogen-fluoride and selective hydrolyses. The nature of the anomeric linkages, established by chromic acid oxidation, was confirmed by 1H-coupled 13C-n.m.r. spectroscopy. Two dimensional n.m.r. studies on a low molecular weight polymer obtained by bacteriophage depolymerization are also reported. (formula; see text)
通过甲基化分析和核磁共振光谱法发现,大肠杆菌K31的荚膜多糖基于所示的六糖。重复单元的序列是根据β-消除、锂-乙二胺降解、氟化氢和选择性水解的综合结果推导出来的。通过铬酸氧化确定的异头键连接性质,经1H耦合13C核磁共振光谱法得到证实。还报道了对通过噬菌体解聚获得的低分子量聚合物的二维核磁共振研究。(分子式;见正文)