Mapping O-glycosylation Sites Using OpeRATOR and LC-MS

Area of Science:

• Biochemistry
• Proteomics
• Glycobiology

Background:

• O-glycosylation is a complex posttranslational modification.
• Analyzing O-glycans is difficult due to their instability and tendency to cluster.
• Existing methods for O-glycan analysis by LC-MS are often challenging.

Purpose of the Study:

• To present a simplified workflow for in-depth O-glycosylation site analysis.
• To demonstrate the utility of OpeRATOR protease in O-glycan analysis.
• To enable detailed mapping of O-glycosylation sites on heavily glycosylated proteins.

Main Methods:

• Utilized OpeRATOR, an O-glycan-specific protease, for protein digestion.
• Generated glycopeptides by cleaving N-terminally to glycosylated serine and threonine residues.
• Performed bottom-up LC-MS/MS analysis coupled with HILIC for glycopeptide separation and identification.

Main Results:

• OpeRATOR digestion produced glycopeptides of suitable size for detailed analysis.
• The workflow enabled effective mapping of O-glycosylation sites.
• Successfully analyzed heavily glycosylated proteins.

Conclusions:

• The OpeRATOR-based workflow offers a simplified approach for O-glycosylation site analysis.
• This method enhances the capability of bottom-up LC-MS/MS for studying complex glycosylation patterns.
• Facilitates detailed characterization of O-glycosylation in proteomics.