Annotation of a serum N-glycan library for rapid identification of structures

J Proteome Res. 2012 Mar 2;11(3):1958-68. doi: 10.1021/pr2011439. Epub 2012 Feb 22.

Abstract

Glycosylation is one of the most common post-translational modifications of proteins and has been shown to change with various pathological states including cancer. Global glycan profiling of human serum based on mass spectrometry has already led to several promising markers for diseases. The changes in glycan structure can result in altered monosaccharide composition as well as in the linkages between the monosaccharides. High-throughput glycan structural elucidation is not possible because of the lack of a glycan template to expedite identification. In an effort toward rapid profiling and identification of glycans, we have constructed a library of structures for the serum glycome to aid in the rapid identification of serum glycans. N-Glycans from human serum glycoproteins are used as a standard and compiled into a library with exact structure (composition and linkage), liquid chromatography retention time, and accurate mass. Development of the library relies on highly reproducible nanoLC-MS retention times. Tandem MS and exoglycosidase digestions were used for structural elucidation. The library currently contains over 300 entries with 50 structures completely elucidated and over 60 partially elucidated structures. This database is steadily growing and will be used to rapidly identify glycans in unknown biological samples.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Carbohydrate Conformation
  • Carbohydrate Sequence
  • Chromatography, High Pressure Liquid / standards
  • Databases, Protein*
  • Glycoproteins / blood*
  • Glycoproteins / chemistry
  • Glycoside Hydrolases / chemistry
  • Glycosylation
  • Humans
  • Molecular Sequence Annotation
  • Molecular Sequence Data
  • Polysaccharides / blood*
  • Polysaccharides / chemistry
  • Protein Isoforms / blood
  • Protein Isoforms / chemistry
  • Protein Processing, Post-Translational
  • Reference Standards
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / standards
  • Tandem Mass Spectrometry / standards

Substances

  • Glycoproteins
  • Polysaccharides
  • Protein Isoforms
  • Glycoside Hydrolases