title: Structural investigation of cell wall polysaccharides of Lactobacillus delbrueckii subsp. bulgaricus 17.
abstract: Lactobacilli are valuable strains for commercial (functional) food fermentations. Their cell surface-associated polysaccharides (sPSs) possess important functional properties, such as acting as receptors for bacteriophages (bacterial viruses), influencing autolytic characteristics and providing protection against antimicrobial peptides. The current report provides an elaborate molecular description of several surface carbohydrates of Lactobacillus delbrueckii subsp. bulgaricus strain 17. The cell surface of this strain was shown to contain short chain poly(glycerophosphate) teichoic acids and at least two different sPSs, designated here as sPS1 and sPS2, whose chemical structures were examined by 2D nuclear magnetic resonance spectroscopy and methylation analysis. Neutral branched sPS1, extracted with n-butanol, was shown to be composed of hexasaccharide repeating units (-[α-d-Glcp-(1-3)-]-4-β-l-Rhap2OAc-4-β-d-Glcp-[α-d-Galp-(1-3)]-4-α-Rhap-3-α-d-Galp-), while the major component of the TCA-extracted sPS2 was demonstrated to be a linear d-galactan with the repeating unit structure being (-[Gro-3P-(1-6)-]-3-β-Galf-3-α-Galp-2-β-Galf-6-β-Galf-3-β-Galp-).
authors.affiliation: National Research Council, 100 Sussex Dr, K1A 0R6 Ottawa, Canada.
authors.forename: E
authors.initials: E
authors.lastname: Vinogradov
authors.affiliation: Equipe BPA, Université du Littoral-Côte d'Opale, Bd Bassin Napoléon, BP 120, 62327 Boulogne-sur-mer, France.
authors.forename: I
authors.initials: I
authors.lastname: Sadovskaya
authors.affiliation: Department of Microbiology, University College Cork, Cork, Ireland.
authors.forename: A
authors.initials: A
authors.lastname: Cornelissen
authors.affiliation: Department of Microbiology, University College Cork, Cork, Ireland; Alimentary Pharmabiotic Centre, Biosciences Institute, University College Cork, Cork, Ireland. Electronic address: d.vansinderen@ucc.ie.
authors.forename: D
authors.initials: D
authors.lastname: van Sinderen
mesh_terms: D002240:Carbohydrate Sequence; D002473:Cell Wall / Q000737:chemistry*; D005994:Glycerophosphates / Q000737:chemistry; D048668:Lactobacillus delbrueckii / Q000737:chemistry / Q000166:cytology*; D008969:Molecular Sequence Data; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D005994:Glycerophosphates; D011135:Polysaccharides, Bacterial
keywords: Cell-wall polysaccharide; Lactobacillus delbrueckii subsp. bulgaricus 17; NMR; Structure; Surface-associated polysaccharide