title: Polysaccharide structural variability in mycobacteria: identification and characterization of phosphorylated mannan and arabinomannan.
abstract: Arabinomannan (AMannan) and mannan (Mannan) are major polysaccharides antigens of the mycobacterial capsule. They are highly related to the lipoarabinomannan (LAM) and lipomannan (LM) lipoglycans of the cell wall, known to participate to the immunopathogenesis of mycobacterial infections. Here we present the identification of two related polysaccharides from Mycobacterium kansasii that co-purified with AMannan and Mannan. Structural analysis using GC, MALDI-MS and NMR clearly established these molecules as non-acylated phosphorylated AMannan and Mannan designated P-AMannan and P-Mannan, respectively. These glycoconjugates represent a new source of polysaccharide structural variability in mycobacteria and constitute unique tools for structure-activity relationship studies in order to investigate the role of fatty acids in the biological functions of LAM and LM. The potential participation of these polysaccharides in influencing the outcome of the infection is also discussed.
authors.affiliation: Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq cedex, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Maes
authors.forename: Bernadette
authors.initials: B
authors.lastname: Coddeville
authors.forename: Laurent
authors.initials: L
authors.lastname: Kremer
authors.forename: Yann
authors.initials: Y
authors.lastname: Guérardel
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D008351:Mannans / Q000737:chemistry* / Q000378:metabolism; D008969:Molecular Sequence Data; D019909:Mycobacterium kansasii / Q000737:chemistry* / Q000378:metabolism; D019906:Nuclear Magnetic Resonance, Biomolecular; D011134:Polysaccharides / Q000737:chemistry* / Q000378:metabolism; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D008351:Mannans; D011134:Polysaccharides; D011135:Polysaccharides, Bacterial; C012189:arabinomannan