The O28 Antigen Gene Clusters ofSalmonella entericasubsp.entericaSerovar Dakar and Serovar Pomona Are Different

Abstract

A 10 kb O-antigen gene cluster was sequenced from aSalmonella entericasubsp.entericaDakar O28 reference strain and from twoS. Pomona serogroup O28 isolates. The twoS. Pomona O antigen gene clusters showed only moderate identity with theS. Dakar O28 gene cluster, suggesting that the O antigen oligosaccharides may contain one or more sugars conferring the O28 epitope but may otherwise be different. These novel findings are absolutely critical for the correct interpretation of molecular serotyping assays targeting genes within the O antigen gene clusters of theseSalmonellaserotypes and suggest the possibility that the O antigen gene clusters of otherSalmonellaserovars may also be heterogenous.