title: Structure of an acidic exopolysaccharide produced by the diazotrophic endophytic bacterium Burkholderia brasiliensis.
abstract: The structure of an exopolysaccharide (EPS) produced by Burkholderia brasiliensis, a diazotrophic endophytic organism originally isolated from rice roots, has been determined. The bacterium was grown in a synthetic medium, containing mannitol and glutamate, which favours the expression of two anionic EPSs, which were separated by anion-exchange chromatography. The structure of the repeat unit of EPS A, eluted at higher ionic strength, was determined by a combination of methylation analysis, partial hydrolysis, chemical degradations, and NMR spectroscopic studies, and shown to be the linear O-acetylated pentasaccharide: -->4)-alpha-D-Glcp-(1-->2)-alpha-L-Rhap-(1-->4)-alpha-D-GlcpA-(1-->3)-beta-L-Rhap[2OAc]-(1-->4)-beta-D-Glcp-(1-->.
authors.affiliation: Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Brasil.
authors.forename: K A
authors.initials: KA
authors.lastname: Mattos
authors.forename: C
authors.initials: C
authors.lastname: Jones
authors.forename: N
authors.initials: N
authors.lastname: Heise
authors.forename: J O
authors.initials: JO
authors.lastname: Previato
authors.forename: L
authors.initials: L
authors.lastname: Mendonça-Previato
mesh_terms: D019117:Burkholderia / Q000235:genetics / Q000378:metabolism*; D002240:Carbohydrate Sequence; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D011135:Polysaccharides, Bacterial