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Published on: December 23, 2022
The expression of an R3 lipopolysaccharide-core by pathotypes of Escherichia coli
H Chart1, N T Perry, C Jenkins
1Laboratory of Enteric Pathogens, Division of Gastrointestinal Infections, Central Public Health Laboratory, London, UK. henrik.chart@hpa.org.uk
Aims:
To investigate the incidence of an R3 lipopolysaccharide (LPS)-core amplicon in a range of pathotypes of Escherichia coli, including Verocytotoxin-producing E. coli (VTEC), enteroaggregative E. coli (EAggEC) and enteropathogenic E. coli (EPEC).
Methods And Results:
A total of 100 strains of E. coli belonging to a range of pathotypes, including 41 strains of VTEC, were screened for the genes encoding the R3 LPS-core using PCR. Fifty-four per cent produced an amplicon with the R3 primer set. Of the 41 VTEC, 66% had an R3 LPS-core with a PCR product being observed with all strains belonging to serotypes O26:H11, O111ac:H- and O145:H25. However, 46% of enteroaggregative E. coli and 50% of enteropathogenic E. coli were also shown to have an R3 LPS-core structure.
Conclusions:
Strains with an R3 LPS-core are widely distributed within the species E. coli.
Significance And Impact Of The Study:
Strains of E. coli with an R3 LPS-core structure appear not to be associated with a specific pathotype.
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