Characterization of a Novel O-GlcNAcylation Site on the Arabidopsis Transcription Factor RGA Using Electron Transfer Dissociation Mass Spectrometry

摘要

We identified a single O-GlcNAcylated peptide located within the Nterminal domain of RGA O-GlcNAcylated on Ser116. The modified peptide was present at the 1percent level. As a consequence of low level and poor charge distribution neither ETD nor CAD fragmentation have yielded complete sequence coverage of this peptide. We have employed peptide coupling chemistry to add additional positive charge that enhances ETD fragmentation Future work will be aimed at enriching low level GlcNAcylated peptides.