Plant N-glycan profiling of minute amounts of material

Anal Biochem. 2008 Aug 1;379(1):66-72. doi: 10.1016/j.ab.2008.04.034. Epub 2008 Apr 25.

Abstract

Development of convenient strategies for identification of plant N-glycan profiles has been driven by the emergence of plants as an expression system for therapeutic proteins. In this article, we reinvestigated qualitative and quantitative aspects of plant N-glycan profiling. The extraction of plant proteins through a phenol/ammonium acetate procedure followed by deglycosylation with peptide N-glycosidase A (PNGase A) and coupling to 2-aminobenzamide provides an oligosaccharide preparation containing reduced amounts of contaminants from plant cell wall polysaccharides. Such a preparation was also suitable for accurate qualitative and quantitative evaluation of the N-glycan content by mass spectrometry. Combining these approaches allows the profiling to be carried out from as low as 500 mg of fresh leaf material. We also demonstrated that collision-induced dissociation (CID) mass spectrometry in negative mode of N-glycans harboring alpha(1,3)- or alpha(1,6)-fucose residue on the proximal GlcNAc leads to specific fragmentation patterns, thereby allowing the discrimination of plant N-glycans from those arising from mammalian contamination.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromatography, High Pressure Liquid
  • Glycopeptides / chemistry
  • Glycopeptides / metabolism
  • Medicago sativa / chemistry
  • Nicotiana / chemistry
  • Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase / metabolism
  • Plant Leaves / chemistry
  • Plants / chemistry*
  • Polysaccharides / analysis*
  • Polysaccharides / chemistry
  • Polysaccharides / isolation & purification*
  • Spectrometry, Mass, Electrospray Ionization
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • ortho-Aminobenzoates / chemistry

Substances

  • Glycopeptides
  • Polysaccharides
  • ortho-Aminobenzoates
  • Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase
  • anthranilamide