Structural studies of the lipopolysaccharide from Salmonella typhimurium 902 (ColIb drd2).

Salmonella typhimurium infected with the plasmid ColIb drd2 gave rise to changes in the composition of the bacterial lipopolysaccharide. Bacteria carrying the wild-type ColIb, the revertant of drd2 to the wild type, or the noncolicinogenic strain resulting from the elimination of ColIb drd2, showed no changes in the sugar composition of the lipopolysaccharide. The structure of the O-specific side chains of the lipopolysaccharide produced by S. typhimurium 902, infected with derepressed ColIb mutants has been investigated. As a result of these studies, it is proposed that the O-specific side chains are composed of chemical repeating units with the following structure: (formula: see text).