title: Some structural features of an insoluble alpha-D-glucan from a mutant strain of Leuconostoc mesenteroides NRRL B-1355.
abstract: Leuconostoc mesenteroides strain NRRL B-1355 produces two soluble extracellular alpha-D-glucans from sucrose: alternan and dextran. An unusual mutant strain derived from NRRL B-1355 has recently been isolated which produces practically no soluble polysaccharide, but significant amounts of an insoluble D-glucan. Methylation analysis shows it contains linear (1-->3) and (1-->6) linkages as well as (1-->2) and (1-->3) branch linkages. The insoluble glucan was partially digestible by endodextranase, giving rise to a series of oligosaccharides, a high-molecular weight soluble fraction and an insoluble residue. Treatment of the soluble dextranase-limit fraction with an alpha(1-->2) debranching enzyme led to further dextranase susceptibility. Methylation, FTIR and NMR analyses of the dextranase-treated fractions indicate a non-uniform structure with domains bearing similarities to L. mesenteroides strain NRRL B-1299 dextran and to insoluble streptococcal D-glucans.
authors.affiliation: Biopolymer Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, US Department of Agriculture, 1815 N University Street, Peoria, IL 61604-3999, USA.
authors.forename: G L
authors.initials: GL
authors.lastname: Cote
authors.forename: J A
authors.initials: JA
authors.lastname: Ahlgren
authors.forename: M R
authors.initials: MR
authors.lastname: Smith
mesh_terms: D002241:Carbohydrates / Q000032:analysis; D002850:Chromatography, Gel; D005936:Glucans / Q000096:biosynthesis / Q000737:chemistry*; D007934:Leuconostoc / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D019906:Nuclear Magnetic Resonance, Biomolecular; D009904:Optical Rotation; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D002241:Carbohydrates; D005936:Glucans