title: A novel rhamno-mannan exopolysaccharide isolated from biofilms of Burkholderia multivorans C1576.
abstract: Burkholderia multivorans C1576 is a Gram negative opportunistic pathogen causing serious lung infection in cystic fibrosis patients. Considering that bacteria naturally form biofilms, and exopolysaccharides are recognized as important factors for biofilm architecture set-up, B. multivorans was grown both in biofilm and in non-biofilm mode on two different media in order to compare the exopolysaccharides biosynthesized in these different experimental conditions. The exopolysaccharides produced were purified and their structure was determined resorting mainly to NMR spectroscopy, ESI mass spectrometry and gas chromatography coupled to mass spectrometry. The experimental data showed that both in biofilm and non-biofilm mode B. multivorans C1576 produced a novel exopolysaccharide having the following structure: [Formula: see text]. About 50% of the 2-linked rhamnose residues are substituted on C-3 with a methyl ether group. The high percentage of deoxysugar Rha units, coupled with OMe substitutions, suggest a possible role for polymer domains with marked hydrophobic characteristics able to create exopolysaccharide junction zones favouring the stability of the biofilm matrix.
authors.affiliation: Department of Life Sciences, Bldg C11, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Dolfi
authors.affiliation: Department of Life Sciences, Bldg C11, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy.
authors.forename: Aris
authors.initials: A
authors.lastname: Sveronis
authors.affiliation: Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy.
authors.forename: Alba
authors.initials: A
authors.lastname: Silipo
authors.affiliation: Department of Life Sciences, Bldg C11, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Rizzo
authors.affiliation: Department of Life Sciences, Bldg C11, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy. Electronic address: pcescutti@units.it.
authors.forename: Paola
authors.initials: P
authors.lastname: Cescutti
mesh_terms: D018441:Biofilms; D019117:Burkholderia / Q000737:chemistry / Q000502:physiology*; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D008351:Mannans / Q000737:chemistry* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000302:isolation & purification; D012210:Rhamnose / Q000737:chemistry
chemical_list: D008351:Mannans; D011135:Polysaccharides, Bacterial; D012210:Rhamnose
keywords: Biofilm; Burkholderia multivorans C1576; Cystic fibrosis; Exopolysaccharide structure; NMR