title: Chemical structure of the cell wall-associated polysaccharide of Bifidobacterium animalis subsp. lactis LKM512.
abstract: We have demonstrated that Bifidobacterium animalis subsp. lactis LKM512 had some probiotic properties in vivo and in vitro. To further understand their mechanisms, the chemical structure of the extracellular polysaccharide that constructs the cell envelope was determined. The strain was anaerobically cultured in MRS broth at 37 °C for 20 h, then the bacterial cells were harvested by centrifugation and washed. The cell wall-associated polysaccharide (CPS) was prepared from the cell wall component digested by lysozyme. The results of anion exchange and gel filtration chromatography showed that the polysaccharide was negatively charged and had a high molecular mass. The CPS was found to compose of galactopyranosyl, galactofuranosyl, glucopyranosyl and rhamnopyranosyl residues in the molar ratio of 1:1:1:3 by using methylation analysis with GC-MS and HPLC profiling. From the results of the structural characterization by 1 dimensional and 2 dimensional NMR spectroscopy, the polysaccharide was established to be a hexasaccharide repeating unit with the following structure: LKM512.
authors.affiliation: Dairy Science and Technology Institute, Kyodo Milk Industry Co. Ltd., 20-1 Hirai, Hinode-machi, Tokyo, 190-0182, Japan, YusukeUEMURA999@gmail.com.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Uemura
authors.forename: Mitsuharu
authors.initials: M
authors.lastname: Matsumoto
mesh_terms: D001644:Bifidobacterium / Q000737:chemistry*; D002240:Carbohydrate Sequence; D066241:Carbon-13 Magnetic Resonance Spectroscopy; D002473:Cell Wall / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D008745:Methylation; D008969:Molecular Sequence Data; D010710:Phosphates / Q000032:analysis; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D066244:Proton Magnetic Resonance Spectroscopy
chemical_list: D010710:Phosphates; D011134:Polysaccharides