Structure of the O-polysaccharide and characterization of the O-antigen gene cluster of Salmonella enterica O53

The O-polysaccharide (O-antigen) of Salmonella enterica O53 was isolated by mild acid degradation of the lipopolysaccharide and studied by sugar analysis and 1H and 13C NMR spectroscopy before and after O-deacetylation. The following structure of the tetrasaccharide O-unit was established:Figure optionsDownload full-size imageDownload as PowerPoint slideSequencing of the O-antigen gene cluster of S. enterica O53 revealed 11 open reading frames having the same transcriptional direction. The functions were tentatively assigned to the genes based on their similarity to related genes from the available databases and taking into account the S. enterica O53-polysaccharide structure.

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