Studies on the O-polysaccharide of Escherichia albertii O2 characterized by non-stoichiometric O-acetylation and non-stoichiometric side-chain l-fucosylation

• Published in: Carbohydrate research 2018-05, Vol.461, p.80-84
• Main Authors: Naumenko, Olesya I., Zheng, Han, Xiong, Yanwen, Senchenkova, Sof'ya N., Wang, Hong, Shashkov, Alexander S., Li, Qun, Wang, Jianping, Knirel, Yuriy A.
• Format: Article
• Language: English
• Subjects: Acetylation; Bacterial polysaccharide structure; Carbohydrate Sequence; Escherichia albertii; Escherichia coli - chemistry; Escherichia coli - genetics; l-Fucosylation; Multigene Family - genetics; O Antigens - chemistry; O Antigens - genetics; O-Acetylation; O-antigen gene cluster; O-Specific polysaccharide
• ISSN: 0008-6215; 1873-426X
• DOI: 10.1016/j.carres.2018.02.013

An O-polysaccharide was isolated from the lipopolysaccharide of Escherichia albertii O2 and studied by chemical methods and 1D and 2D 1H and 13C NMR spectroscopy. The following structure of the O-polysaccharide was established: ▪. The O-polysaccharide is characterized by masked regularity owing to a non-stoichiometric O-acetylation of an l-fucose residue in the main chain and a non-stoichiometric side-chain l-fucosylation of a β-GlcNAc residue. A regular linear polysaccharide was obtained by sequential Smith degradation and alkaline O-deacetylation of the O-polysaccharide. The content of the O-antigen gene cluster of E. albertii O2 was found to be essentially consistent with the O-polysaccharide structure established. [Display omitted] •O-polysaccharide was isolated from Escherichia albertii serotype O2 and analyzed.•Sugar analysis, Smith degradation and NMR spectroscopy were used for analysis.•The O-polysaccharide contains non-stoichiometric side-chain l-fucose and O-acetyl group.•The gene cluster for the O-polysaccharide biosynthesis is consistent with the structures.