Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Associated disease: infection due to Escherichia coli [ICD11:
XN6P4 
]
The structure was elucidated in this paperNCBI PubMed ID: 29220644Publication DOI: 10.1016/j.carres.2017.11.016Journal NLM ID: 0043535Publisher: Elsevier
Correspondence: A.V. Perepelov <andreivperepelov

gmail.com>
Institutions: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China
The O-specific polysaccharide (O-antigen) is a part of the lipopolysaccharide on the cell surface of Gram-negative bacteria. The O-polysaccharide was obtained by mild acid hydrolysis of the lipopolysaccharide of Escherichia coli O27 and studied by sugar analysis and Smith degradation along with 1H and 13C NMR spectroscopy. The following structure of the branched hexasaccharide repeating unit was established, which is unique among known structures of bacterial polysaccharides:where GlcA is non-stoichiometrically O-acetylated at position 3 (∼22%) or 4 (∼37%). Functions of genes in the O-antigen gene cluster of E. coli O27 were tentatively assigned by comparison with sequences in the available databases and found to be consistent with the O-polysaccharide structure.
Lipopolysaccharide, O-antigen, Escherichia coli, O-specific polysaccharide, O-antigen gene cluster, O-Polysaccharide structure
Structure type: polymer chemical repeating unit
Location inside paper: abstract, p.3, OPS
Compound class: O-polysaccharide, O-antigen
Contained glycoepitopes: IEDB_115136,IEDB_130648,IEDB_136906,IEDB_137472,IEDB_137473,IEDB_140529,IEDB_140630,IEDB_141794,IEDB_142488,IEDB_146664,IEDB_151528,IEDB_167069,IEDB_190606,IEDB_423153,IEDB_983931,SB_192,SB_25,SB_7
Methods: 13C NMR, 1H NMR, NMR-2D, sugar analysis, ESI-MS, GLC, mild acid hydrolysis, Smith degradation, de-O-acetylation, GPC, delipidation, function analysis of gene clusters
Comments, role: O-polysaccharide from E. coli O27 type strain E1020-72 (laboratory stock number G1285).
Related record ID(s): 12463
NCBI Taxonomy refs (TaxIDs): 1095710
Show glycosyltransferases
There is only one chemically distinct structure: