Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Host organism: Homo sapiens
Associated disease: infection due to Escherichia coli [ICD11:
XN6P4 
]
The structure was elucidated in this paperNCBI PubMed ID: 25512310Publication DOI: 10.1128/JB.02398-14Journal NLM ID: 2985120RPublisher: American Society for Microbiology
Correspondence: Y.A. Knirel <yknirel
gmail.com>; letarov
gmail.com
Institutions: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia, TEDA School of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China, S. N. Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow, Russia, Institute of Physical and Chemical Medicine, Federal Medical and Biological Agency, Moscow, Russia, Institute of Physical and Chemical Medicine, Federal Medical and Biological Agency, Moscow, Russia Kazan Federal University, Kazan, Russia
The O polysaccharide of the lipopolysaccharide (O antigen) of Gram-negative bacteria often serves as a receptor for bacteriophages that can make the phage dependent on a given O-antigen type, thus supporting the concept of the adaptive significance of the O-antigen variability in bacteria. The O-antigen layer also modulates interactions of many bacteriophages with their hosts, limiting the access of the viruses to other cell surface receptors. Here we report variations of O-antigen synthesis and structure in an environmental Escherichia coli isolate, 4s, obtained from horse feces, and its mutants selected for resistance to bacteriophage G7C, isolated from the same fecal sample. The 4s O antigen was found to be serologically, structurally, and genetically related to the O antigen of E. coli O22, differing only in side-chain a-D-glucosylation in the former, mediated by a gtr locus on the chromosome. Spontaneous mutations of E. coli 4s occurring with an unusually high frequency affected either O-antigen synthesis or O-acetylation due to the inactivation of the gene encoding the putative glycosyltransferase WclH or the putative acetyltransferase WclK, respectively, by the insertion of IS1-like elements. These mutations induced resistance to bacteriophage G7C and also modified interactions of E. coli 4s with several other bacteriophages conferring either resistance or sensitivity to the host. These findings suggest that O-antigen synthesis and O-acetylation can both ensure the specific recognition of the O-antigen receptor following infection by some phages and provide protection of the host cells against attack by other phages.
O-antigen, Escherichia coli, O-acetylation, bacteriophage
Structure type: polymer chemical repeating unit
Location inside paper: p.908, fig.4, E. coli 4sI-2, E. coli 4sI-4
Compound class: O-polysaccharide, O-antigen
Contained glycoepitopes: IEDB_115136,IEDB_130648,IEDB_136906,IEDB_137472,IEDB_137473,IEDB_140630,IEDB_141794,IEDB_142488,IEDB_144990,IEDB_144998,IEDB_146664,IEDB_151528,IEDB_167071,IEDB_190606,IEDB_423153,IEDB_983931,SB_192,SB_21,SB_7
Methods: 13C NMR, 1H NMR, NMR-2D, SDS-PAGE, DNA techniques, serological methods, genetic methods, bioinformatic analysis
Biosynthesis and genetic data: genetic data
Comments, role: Mutant strains of E. coli 4s.
Related record ID(s): 30623, 30796
NCBI Taxonomy refs (TaxIDs): 562Reference(s) to other database(s): GTC:G71018MQ
Show glycosyltransferases
There is only one chemically distinct structure:
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