Relatedness of the O-polysaccharide structures of Escherichia coli O123 and Salmonella enterica O58, both containing 4,6-dideoxy-4-{N-[(S)-3-hydroxybutanoyl]-d-alanyl}amino-d-glucose; revision of the E. coli O123 O-polysaccharide structure Original Resear

where l-QuipNAc stands for 2-acetamido-2,6-dideoxy-l-glucose and d-Qui4NAlaHb for 4-{N-[(S)-3-hydroxybutanoyl]-d-alanyl}amino-4,6-dideoxy-d-glucose. The latter was isolated as an ethylene glycol glycoside by three sequential Smith degradations of the O-deacetylated O-polysaccharide. The structure established in this work is at variance with the E. coli O123-polysaccharide structure reported earlier [Clark, C. G.; Kropinski, A. M.; Parolis, H.; Grant, C. C.; Trout-Yakel, K. M.; Franklin, K.; Ng, L. K.; Paramonov, N. A.; Parolis, L. A.; Rahn, K.; Tabor, H. J. Med. Microbiol. 2009, 58, 884–894]. In accordance with the genetic data, the O-polysaccharide of S. enterica O58 has the same structure, except for it lacks the O-acetylation.