Diethylaminoethyl Sepharose (DEAE-Sepharose) Microcolumn for Enrichment of Glycopeptides

Anal Bioanal Chem. 2017 Jan;409(2):511-518. doi: 10.1007/s00216-016-9937-6. Epub 2016 Sep 27.

Abstract

N-Glycosylation is one of the most prevalent protein post-translational modifications and is involved in many biological processes, such as protein folding, cellular communications, and signaling. Alteration of N-glycosylation is closely related to the pathogenesis of diseases. Thus, the investigation of protein N-glycosylation is crucial for the diagnosis and treatment of disease. In this research, we applied diethylaminoethanol (DEAE) Sepharose solid-phase extraction microcolumns for N-glycopeptide enrichment. This method integrated the advantages of Click Maltose and zwitterionic HILIC (ZIC-HILIC) and showed a relatively higher specificity for N-glycosylated peptides. This strategy was then applied to tryptic digests of normal human serum, followed by deglycosylation using peptide-N-glycosidase F (PNGase F) in H218O. Subsequent LC-MS/MS analysis allowed for the assignment of 219 N-glycosylation sites from 115 serum N-glycoproteins. This study provides an alternative approach for N-glycopeptide enrichment and the method employed is effective for large-scale N-glycosylation site identification. Graphical abstract Proposed mechanism of glycopeptides enrichment using DEAE-Sepharose.

Keywords: Amino acids/peptides; Biological samples; Mass spectrometry/ICP-MS.

MeSH terms

  • Glycopeptides / blood
  • Glycopeptides / chemistry*
  • Glycopeptides / isolation & purification*
  • Glycosylation
  • Humans
  • Sepharose / chemistry*
  • Solid Phase Extraction / instrumentation*

Substances

  • Glycopeptides
  • Sepharose