Isolation and composition of an alkali-soluble glucan from the cell walls of Saccharomyces cerevisiae

J Gen Microbiol. 1976 May;94(1):180-92. doi: 10.1099/00221287-94-1-180.


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

  • Cell Fractionation
  • Cell Wall / analysis
  • Cell Wall / ultrastructure
  • Glucose / analysis
  • Hexosamines / analysis
  • Mannose / analysis
  • Molecular Weight
  • Nitrogen / analysis
  • Polysaccharides / analysis*
  • Saccharomyces cerevisiae / analysis*
  • Saccharomyces cerevisiae / ultrastructure
  • Sodium Hydroxide
  • Solubility


  • Hexosamines
  • Polysaccharides
  • Sodium Hydroxide
  • Glucose
  • Nitrogen
  • Mannose