title: Structures of the O-polysaccharides and classification of Proteus genomospecies 4, 5 and 6 into respective Proteus serogroups.
abstract: An acidic branched O-polysaccharide was isolated by mild acid degradation of the lipopolysaccharide (LPS) of Proteus genomospecies 4 and studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, ROESY and H-detected 1H, 13C HSQC experiments. The following structure of the pentasaccharide repeating unit of the O-polysaccharide was established, which is unique among Proteus polysaccharide structures: [structure: see text] where Qui3NAc stands for 3-acetamido-3,6-dideoxyglucose. Based on the O-polysaccharide structure and serological data, we propose classifying Proteus genomospecies 4 into a new, separate Proteus serogroup, O56. A weak cross-reactivity of Proteus genomospecies 4 antiserum with LPS of Providencia stuartii O18 and Proteus vulgaris OX2 was observed and is discussed in view of a similarity of the O-polysaccharide structures. Structural and serological investigations showed that Proteus genomospecies 5 and 6 should be classified into the existing Proteus serogroups O8 and O69, respectively.
authors.affiliation: Department of General Microbiology, Institute of Microbiology and Immunology, University of Łódź, Poland.
authors.forename: Krystyna
authors.initials: K
authors.lastname: Zych
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Perepelov
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Siwinska
authors.forename: Yuriy A
authors.initials: YA
authors.lastname: Knirel
authors.forename: Zygmunt
authors.initials: Z
authors.lastname: Sidorczyk
mesh_terms: D000906:Antibodies / Q000276:immunology; D002240:Carbohydrate Sequence; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D019081:O Antigens / Q000737:chemistry*; D011511:Proteus / Q000737:chemistry* / Q000145:classification*
chemical_list: D000906:Antibodies; D019081:O Antigens