Title : Site-Specific Profiling of
Serum Glycoproteins Using N-Linked Glycan and Glycosite Analysis Revealing Atypical N-Glycosylation Sites on
Albumin and
α-1B-Glycoprotein
Abstract :
- Most serum proteins are N-linked glycosylated, and therefore the glycoproteomic profiling of serum is essential for characterization of serum proteins
- In this study, we profiled serum N-glycoproteome by our recently developed N-glycoproteomic method using solid-phase extraction of N-linked glycans and glycosite-containing peptides (NGAG) coupled with LC-MS/MS and site-specific glycosylation analysis using GPQuest software
- Our data indicated that half of identified N-glycosites were modified by at least two glycans , with a majority of them being sialylated
- Specifically, 3/4 of glycosites were modified by biantennary N-glycans and 1/3 of glycosites were modified by triantennary sialylated N-glycans
- In addition, two novel atypical glycosites (with N-X-V motif ) were identified and validated from albumin and α -1B-glycoprotein
- The widespread presence of these two glycosites among individuals was further confirmed by individual serum analyses