Tools for Glycoproteomic Analysis: Size Exclusion Chromatography Facilitates Identification of Tryptic Glycopeptides with N-linked Glycosylation Sites

Citations Over TimeTop 10% of 2006 papers

Abstract

Proteomic techniques, such as HPLC coupled to tandem mass spectrometry (LC-MS/MS), have proved useful for the identification of specific glycosylation sites on glycoproteins (glycoproteomics). Glycosylation sites on glycopeptides produced by trypsinization of complex glycoprotein mixtures, however, are particularly difficult to identify both because a repertoire of glycans may be expressed at a particular glycosylation site, and because glycopeptides are usually present in relatively low abundance (2% to 5%) in peptide mixtures compared to nonglycosylated peptides. Previously reported methods to facilitate glycopeptide identification require either several pre-enrichment steps, involve complex derivatization procedures, or are restricted to a subset of all the glycan structures that are present in a glycoprotein mixture. Because the N-linked glycans expressed on tryptic glycopeptides contribute substantially to their mass, we demonstrate that size exclusion chromatography (SEC) provided a significant enrichment of N-linked glycopeptides relative to nonglycosylated peptides. The glycosylated peptides were then identified by LC-MS/MS after treatment with PNGase-F by the monoisotopic mass increase of 0.984 Da caused by the deglycosylation of the peptide. Analyses performed on human serum showed that this SEC glycopeptide isolation procedure results in at least a 3-fold increase in the total number of glycopeptides identified by LC-MS/MS, demonstrating that this simple, nonselective, rapid method is an effective tool to facilitate the identification of peptides with N-linked glycosylation sites.

Related Papers

• → Urinary Glycopeptide Analysis for the Investigation of Novel Biomarkers(2018)22 cited
• → An ultrafast and highly efficient enrichment method for both N-Glycopeptides and N-Glycans by bacterial cellulose(2020)13 cited
• → Glycoproteomic software solutions spotlight glycans(2021)12 cited
• → The enzymatic removal of immunoglobulin variable domain glycans by different glycosidases(2019)11 cited
• → Selective reaction monitoring approach using structure-defined synthetic glycopeptides for validating glycopeptide biomarkers pre-determined by bottom-up glycoproteomics(2022)6 cited