The involvement of mnn4 and mnn6 mutations in mannosylphosphorylation of O-linked oligosaccharide in yeast Saccharomyces cerevisiae

Biochim Biophys Acta. 1998 Sep 16;1425(1):255-62. doi: 10.1016/s0304-4165(98)00078-6.

Abstract

The structure of O-linked acidic oligosaccharide from Saccharomyces cerevisiae was analyzed. The chitinase, exclusively O-glycosylated extracelluar protein, was purified from strains mnn1, mnn1 mnn4, mnn1 mnn6 and deltakre2 and the oligosaccharides were hydrolyzed by O-linked sugar chain specific hydrazinolysis. The mannosylphosphorylated mannotriose (M3-P-M) was detected in strain mnn1, but not in the other three strains (mnn1n mnn4, mnn1 mnn6 and deltakre2). alpha-Mannosidase treatment and matrix-assisted laser desorption ionization time-of-flight mass spectrometry of mannosylphosphorylated mannotriose revealed that mannosylphosphate was attached to a middle mannose of alpha-1,2-linked mannotriose. This result indicates that the mnn4 and mnn6 mutations affect the mannosylphosphorylation of O-linked oligosaccharide, together with that of N-linked oligosaccharide. The amount of mannosylphosphorylated mannotriose was 7% of total O-linked oligosaccharides (20% of neutral mannotriose) of chitinase in strain mnn1.

MeSH terms

  • Alkaline Phosphatase
  • Carbohydrate Conformation
  • Carbohydrate Sequence
  • Chromatography, High Pressure Liquid
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism
  • Genes, Fungal
  • Mannosephosphates / chemistry
  • Mannosephosphates / metabolism*
  • Mannosidases
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • Molecular Sequence Data
  • Mutation
  • Oligosaccharides / chemistry
  • Oligosaccharides / metabolism*
  • Phosphorylation
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins*
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • alpha-Mannosidase

Substances

  • Fungal Proteins
  • MNN4 protein, S cerevisiae
  • Mannosephosphates
  • Membrane Proteins
  • Oligosaccharides
  • Saccharomyces cerevisiae Proteins
  • Alkaline Phosphatase
  • Mannosidases
  • alpha-Mannosidase