title: Isolation and composition of an alkali-soluble glucan from the cell walls of Saccharomyces cerevisiae.
abstract: An alkali-soluble glucan was obtained from the cell walls of Saccharomyces cerevisiae NCYC1109 and baker's yeast by extraction with cold, dilute sodium hydroxide under nitrogen. The glucan, which represented approximately 20% of purified glucan was homogeneous and was shown to be free from contamination by other cell-wall polysaccharides by ultracentrifuging, gel filtration and electrophoresis. In addition to glucose, the glucan contained traces of mannose and nitrogen, but no hexosamine. Structural analyses revealed the presence of 80-85% (1 leads to 3)-beta-D linkages, 8-12% (1 leads to 6)-beta-D linkages and 3-4% branched residues linked through C-1, C-3 and C-6. The molecular weight of the glucan was estimated to be about 250000. Electron-microscopic examination of the cell walls after alkali extraction showed that an amorphous surface layer had been removed revealing numerous bud scar structures.
mesh_terms: D002458:Cell Fractionation; D002473:Cell Wall / Q000032:analysis / Q000648:ultrastructure; D005947:Glucose / Q000032:analysis; D006595:Hexosamines / Q000032:analysis; D008358:Mannose / Q000032:analysis; D008970:Molecular Weight; D009584:Nitrogen / Q000032:analysis; D011134:Polysaccharides / Q000032:analysis*; D012441:Saccharomyces cerevisiae / Q000032:analysis* / Q000648:ultrastructure; D012972:Sodium Hydroxide; D012995:Solubility
chemical_list: D006595:Hexosamines; D011134:Polysaccharides; D012972:Sodium Hydroxide; D005947:Glucose; D009584:Nitrogen; D008358:Mannose