Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Host organism: Homo sapiens
Associated disease: bacillary dysentery (shigellosis) [ICD11:
1A02 
, ICD11:
SA56 
, ICD11:
XN7HG 
];
infection due to Shigella flexneri [ICD11:
XN7Y2 
]
The structure was elucidated in this paperNCBI PubMed ID: 24671799Publication DOI: 10.1128/JCM.00197-14Journal NLM ID: 7505564Publisher: American Society for Microbiology
Correspondence: Qiangzheng Sun <sunqiangzheng

icdc.cn>
Institutions: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, China CDC, Changping, Beijing, China, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
Shigella flexneri is the major cause of shigellosis in developing countries. All serotypes except for serotype 6 share an O-antigen backbone composed of a →2)-α-L-RhapIII-(1→2)-α-L-RhapII-(1→3)-α-L-RhapI-(1→3)-β-D-GlcpNAc-(1→ tetrasaccharide repeat. It can be modified by the addition of a glucosyl group to one or more sugar residues and/or an O-acetyl group to RhaI and/or a phosphoethanolamine to RhaII and/or RhaIII. These modifications give rise to type I-, IC-, II-, IV-, and V- and to group 6-, 7,8-, and MASF IV-1-specific antigenic determinants, which comprise the current serotyping scheme of S. flexneri. Recently, another O-antigen modification created by adding an O-acetyl group to RhaIII at position 3 or 4 (3/4-O-acetylation) has been found in S. flexneri serotypes 1a, 1b, 2a, 5a, Y, and 6. A new O-acyltransferase gene named oacB has been shown to mediate the 3/4-O-acetylation in serotypes 1a, 1b, 2a, 5a, and Y but not in 6. In this work, we studied the distribution of the 3/4-O-acetylation in S. flexneri and the antigenicity that resulted from this modification. PCR screening of the oacB gene in clinical isolates of S. flexneri demonstrated that the oacB-mediated 3/4-O-acetylation is widespread in serotypes 1a, 1b, 2a, 5a, and Y. Serological analysis indicated that this modification confers the host with a novel antigenic determinant that is provisionally named group O factor 9. These findings enhance our understanding of the varieties of O-antigenic determinants related to O-antigen modification in S. flexneri and will assist epidemiological studies and vaccine development.
O-antigen, Shigella flexneri, epitope, serotype conversion
Structure type: polymer chemical repeating unit
Location inside paper: p.2035, table 2, 5a (M90T)
Compound class: O-polysaccharide, O-antigen
Contained glycoepitopes: IEDB_125613,IEDB_125614,IEDB_127514,IEDB_130671,IEDB_130692,IEDB_133752,IEDB_133753,IEDB_133754,IEDB_135813,IEDB_135849,IEDB_136105,IEDB_137340,IEDB_141807,IEDB_141815,IEDB_141816,IEDB_142488,IEDB_143253,IEDB_144998,IEDB_146664,IEDB_151531,IEDB_153213,IEDB_158539,IEDB_225177,IEDB_885823,IEDB_983931,SB_192
Methods: 13C NMR, 1H NMR, NMR-2D, PCR, SDS-PAGE, DNA techniques, Western blotting, NMR-1D, serological methods, genetic methods, serotyping analysis
Biological activity: the distribution of the 3/4-O-acetylation was studied in S. flexneri by PCR screening of the oacB gene and serological assay using a specific absorbed antiserum
Comments, role: O-Antigen structure of S. flexneri O factor 9-negative.
Related record ID(s): 30150, 30548, 30549, 30550, 30551, 30552, 30553, 30554, 30555, 30556, 30557
NCBI Taxonomy refs (TaxIDs): 1086030Reference(s) to other database(s): GTC:G88580LT, GlycomeDB:
26158
Show glycosyltransferases
There is only one chemically distinct structure: