title: NMR studies of acetan and the related bacterial polysaccharide, CR1/4, produced by a mutant strain of Acetobacter xylinum.
abstract: Acetan is a bacterial polysaccharide produced by Acetobacter xylinum NRRL B42. Chemical mutagenesis of A.xylinum allowed selection of a mutant strain which produced a new polysaccharide, CR1/4. 2D NMR methods have been used to assign the 1H and 13C spectra of the two polysaccharides and to determine that CR1/4 has the structure shown below. The total number of O-acetyl groups is slightly less than two per repeating unit. [formula: see text] The pentasaccharide side chain of acetan is truncated to a disaccharide unit in CR1/4, but the structures are otherwise identical. In particular, the degree of acetylation is about the same and the O-acetyl groups are located at the same position in both polysaccharides.
authors.affiliation: Institute of Food Research, Norwich Laboratory, Norwich Research Park, Colney, United Kingdom.
authors.forename: I J
authors.initials: IJ
authors.lastname: Colquhoun
authors.forename: M
authors.initials: M
authors.lastname: Defernez
authors.forename: V J
authors.initials: VJ
authors.lastname: Morris
mesh_terms: D002240:Carbohydrate Sequence; D041822:Gluconacetobacter xylinus / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D005947:Glucose / Q000737:chemistry; D005965:Glucuronates / Q000032:analysis; D020723:Glucuronic Acid; D009682:Magnetic Resonance Spectroscopy; D008358:Mannose / Q000032:analysis; D008969:Molecular Sequence Data; D016296:Mutagenesis; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis / Q000737:chemistry*
chemical_list: D005965:Glucuronates; D011135:Polysaccharides, Bacterial; C068545:acetan; D020723:Glucuronic Acid; D005947:Glucose; D008358:Mannose