title: Structural analysis of the extracellular polysaccharide produced by Sphaerotilus natans.
abstract: An extracellular polysaccharide (EPS) was recovered and purified from the culture fluid of a sheathed bacterium, Sphaerotilus natans. Glucose, rhamnose, and aldobiouronic acid were detected in the acid hydrolysate of EPS by thin-layer chromatography (TLC). The aldobiouronic acid was found to be composed of glucuronic acid and rhamnose by TLC and gas-liquid chromatography analyses of the corresponding neutral disaccharide. The structure of EPS was identified by methylation linkage analysis and nuclear magnetic resonance. Additionally, partial acid hydrolysates of EPS were prepared and put through fast atom bombardment-mass spectrometry to determine the sugar sequence of EPS. The resulting data showed that EPS produced by S. natans is a new gellan-like polysaccharide constructed from a tetrasaccharide repeating unit, as shown below. -->4)-alpha-D-Glcp-(1-->2)-beta-D-GlcA p-(1-->2)-alpha-L-Rha p-(1-->3)-beta-L-Rha p-(1-->.
authors.affiliation: Division of Materials Science and Chemical Engineering,Faculty of Engineering, Yokohama National University, Kanagawa, Japan. mtake@ynu.ac.jp
authors.forename: Minoru
authors.initials: M
authors.lastname: Takeda
authors.forename: Shogo
authors.initials: S
authors.lastname: Nomoto
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Koizumi
mesh_terms: D002241:Carbohydrates / Q000737:chemistry; D002849:Chromatography, Gas; D006088:Gram-Negative Aerobic Bacteria / Q000737:chemistry / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D014574:Uronic Acids / Q000032:analysis
chemical_list: D002241:Carbohydrates; D011134:Polysaccharides; D014574:Uronic Acids