title: Use of CID/ETD mass spectrometry to analyze glycopeptides.
abstract: Collision-induced dissociation (CID) tandem mass spectrometry (MS/MS) does not allow the characterization of glycopeptides because of the fragmentation of glycan structures and limited fragmentation of peptide backbones. Electron transfer dissociation (ETD) MS/MS, on the other hand, offers a complementary approach, prompting only peptide backbone fragmentation while keeping post-translational modifications intact. Characterization of glycopeptides using both CID and ETD is summarized in this unit. While CID provides information related to the composition of glycan moieties attached to a peptide backbone, ETD permits de novo sequencing of peptides. Radical anion transfer of electrons to the peptide backbone in ETD induces cleavage of the N-Cα bond. The glycan moiety is retained on the peptide backbone, largely unaffected by the ETD process, thus allowing the identification of the amino acid sequence of a glycopeptide and its glycosylation site. This unit discusses the use of both CID and ETD for better characterization of glycopeptides.
authors.affiliation: Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas.
authors.forename: Yehia
authors.initials: Y
authors.lastname: Mechref
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002853:Chromatography, Liquid; D004583:Electrons; D006020:Glycopeptides / Q000032:analysis* / Q000737:chemistry*; D006031:Glycosylation; D007477:Ions; D013058:Mass Spectrometry / Q000379:methods*; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000737:chemistry; D059748:Proteolysis; D053719:Tandem Mass Spectrometry; D014357:Trypsin / Q000378:metabolism
chemical_list: D006020:Glycopeptides; D007477:Ions; D011134:Polysaccharides; D014357:Trypsin