PMID: 23234360

 

    Legend: Gene, Sites

Title : LC-MS/MS characterization of O-glycosylation sites and glycan structures of human cerebrospinal fluid glycoproteins

Abstract :

1. The GalNAc O-glycosylation on Ser/Thr residues of extracellular proteins has not been well characterized from a proteomics perspective
2. We previously reported a sialic acid capture-and-release protocol to enrich tryptic N- and O-glycopeptides from human cerebrospinal fluid glycoproteins using nano-LC- ESI-MS/MS with collision-induced dissociation (CID) for glycopeptide characterization
3. Here, we have introduced peptide N-glycosidase F ( PNGase F) pretreatment of CSF samples to remove the N-glycans facilitating the selective characterization of O-glycopeptides and enabling the use of an automated CID-MS(2 )/MS(3) search protocol for glycopeptide identification
4. We used electron-capture and -transfer dissociation ( ECD /ETD) to pinpoint the glycosylation site (s) of the glycopeptides , identified as predominantly core-1-like HexHexNAc-O- structure attached to one to four Ser/Thr residues
5. We characterized 106 O-glycosylations and found Pro residues preferentially in the n - 1, n + 1, and/or n + 3 positions in relation to the Ser/Thr attachment site (n)
6. The characterization of glycans and glycosylation sites in glycoproteins from human clinical samples provides a basis for future studies addressing the biological and diagnostic importance of specific protein glycosylations in relation to human disease

Output (sent_index, trigger, protein, sugar, site):

• 0. O-glycosylation, , glycoproteins, -, sites
• 0. glycoproteins, , glycoproteins, glycan structures, -
• 1. O-glycosylation, , -, Ser/Thr residues, residues
• 1. O-glycosylation, , proteins, -, residues
• 1. O-glycosylation, , proteins, O-glycosylation, -
• 1. O-glycosylation, , proteins, O-glycosylation, residues
• 1. O-glycosylation, , proteins, Ser/Thr residues, residues
• 2. O-glycopeptides, , -, -, O-glycopeptides
• 2. glycopeptide, , -, -, glycopeptide
• 2. glycoproteins, , glycoproteins, -, -
• 3. O-glycopeptides, , -, -, O-glycopeptides
• 3. glycopeptide, , -, -, glycopeptide
• 4. attached, , -, predominantly core-1-like HexHexNAc-O- structure, residues
• 4. glycopeptides, , -, -, glycopeptides
• 4. glycosylation, , -, -, glycopeptides
• 4. glycosylation, , -, -, site
• 6. glycans, , glycoproteins, glycans, -
• 6. glycoproteins, , glycoproteins, -, -
• 6. glycosylation, , -, -, sites

Output(Part-Of) (sent_index, protein, site):

• 0. glycoproteins, sites
• 1. proteins, residues
• 6. glycoproteins, sites

*Output_Site_Fusion* (sent_index, protein, sugar, site):

 

Protein	NCBI ID	SENTENCE INDEX