title: Reinvestigation of the structure of Brucella O-antigens.
abstract: O-Specific polysaccharides of Brucella contain two antigenic determinants, called A and M. Most of the strains express epitope A with a small amount of epitope M, whereas Brucella melitensis strain 16 M expresses longer polymer consisting mostly of M-type epitopes. Proposed explanation was that epitope A is defined by 1-2-linked homopolymer of N-formylperosamine (Rha4NFo), while epitope M is a pentasaccharide with four 2- and one 3-substituted Rha4NFo. We reinvestigated both types of structures by 2D NMR and showed that M-epitope is a tetrasaccharide, missing one of the 2-linked Rha4NFo as compared to the previously proposed structure. Polysaccharide from B. melitensis 16 M contains a fragment of 1-2-linked polymer, capped with M-type polymer. Other strains contain one or two M-type units at the non-reducing end of the 1-2-linked O-chain.
authors.affiliation: Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Joanna
authors.initials: J
authors.lastname: Kubler-Kielb
authors.forename: Evgeny
authors.initials: E
authors.lastname: Vinogradov
mesh_terms: D002002:Brucella / Q000737:chemistry*; D019081:O Antigens / Q000737:chemistry*; D009844:Oligosaccharides / Q000737:chemistry
chemical_list: D019081:O Antigens; D009844:Oligosaccharides
keywords: 2-amino-2,6-dideoxy-d-glucose (quinovosamine); 4-amino-4,6-dideoxy-d-mannose (perosamine); 4-formamido-4,6-dideoxy-d-mannose (N-formylperosamine); Brucella; LPS; MS; NMR; QuiN; Rha4N; Rha4NFo; Structure; lipopolysaccharide