Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Associated disease: infection due to Escherichia coli [ICD11:
XN6P4 
]
The structure was elucidated in this paperNCBI PubMed ID: 20482625Journal NLM ID: 9315554Publisher: Elsevier
Correspondence: wangel
nankai.edu.cn
Institutions: Nankai University, Tianjin, China.
O-antigen is the most variable cell wall constituent of Gram-negative bacteria. Escherichia coli and Salmonella enterica are closely related species. In this work, we present structural and genetic evidence for the close relationship between O-antigens of E. coli O71 and S. enterica O28. The E. coli O71 O-antigen was found to consist of tetrasaccharide-repeating units containing d-GalpNAc, d-Galp, l-Rhap, and d-Quip3NAc, with multiple O-acetyl lateral groups. It is very similar to the known structure of the S. enterica O28 O-antigen, which has the same backbone units, but with a lateral Glc residue instead of O-acetyl groups. The O-antigen gene clusters of E. coli O71 and S. enterica O28 were sequenced and found to contain the same genes with high-level similarity. All of the genes expected for the synthesis of the common backbone structure of the two O-antigens were identified based on homology. It is proposed that the two gene clusters had originated from the same ancestor, and diverged by acquiring prophage genes to carry out side-chain modifications. This is a new pair of the closely related E. coli and S. enterica O-serogroups. The serogroup-specific genes of E. coli O71 and S. enterica O28 were also identified.
Escherichia coli, Salmonella enterica, O-antigen structure, O-antigen gene cluster, PCR assay
Structure type: suggested polymer biological repeating unit
Location inside paper: p.165, fig.2B
Compound class: O-polysaccharide, O-antigen
Contained glycoepitopes: IEDB_130648,IEDB_134627,IEDB_136044,IEDB_136105,IEDB_137472,IEDB_137473,IEDB_1391961,IEDB_1391963,IEDB_141584,IEDB_141794,IEDB_143260,IEDB_190606,IEDB_225177,IEDB_885822,IEDB_885823,SB_165,SB_166,SB_187,SB_195,SB_23,SB_24,SB_36,SB_7,SB_8,SB_88,SB_9
Methods: 13C NMR, 1H NMR, NMR-2D, PCR, DNA sequencing, sugar analysis, GLC, de-O-acetylation, genetic methods
Related record ID(s): 25279, 25338, 25669, 25758, 28334, 30355
NCBI Taxonomy refs (TaxIDs): 562Reference(s) to other database(s): GTC:G62779HC
Show glycosyltransferases
There is only one chemically distinct structure:
Found 
report error