Concurrent automated sequencing of the glycan and peptide portions of O-linked glycopeptide anions by ultraviolet photodissociation mass spectrometry.

ABSTRACT: O-Glycopeptides are often acidic owing to the frequent occurrence of acidic saccharides in the glycan, rendering traditional proteomic workflows that rely on positive mode tandem mass spectrometry (MS/MS) less effective. In this report, we demonstrate the utility of negative mode ultraviolet photodissociation (UVPD) MS for the characterization of acidic O-linked glycopeptide anions. This method was evaluated for a series of singly and multiply deprotonated glycopeptides from the model glycoprotein kappa casein, resulting in production of both peptide and glycan product ions that afforded 100% sequence coverage of the peptide and glycan moieties from a single MS/MS event. The most abundant and frequent peptide sequence ions were a/x-type products which, importantly, were found to retain the

SUBMITTER: Madsen JA 

PROVIDER: S-EPMC3816934 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature