Identification of O-glycoproteins by Glycoproteomics based on BEP procedure

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K05804
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Analytical chemistry
• Research Institution: Hokkaido University
• Principal Investigator: Furukawa Jun-ichi 北海道大学, 医学研究院, 特任准教授 (30374193)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 糖タンパク質 / グライコミクス / β脱離反応 / マイケル付加 / O-結合型糖鎖 / BEP法

Outline of Final Research Achievements

Serine (Ser) and threonine (Thr) residues are modified by the O-GalNAc type, typical of mucin. The characterization of O-glycans has remained particularly challenging because no analogous endoglycosidase is known.
We investigated the BEP method for the identification of structural isomer and O-glycosylation sites of proteins/peptides. We developed that aminolysis-SALSA could successfully distinguish sialylated N- and GSL-glycan isomers by mass spectrometry. This method could be applied to the analysis of sialylated O-glycopeptides.
In addition, we investigated the BEP procedure focused on Michael addition. In this study, it was revealed that only serine residues act as Michael acceptor and preform selective Michael addition. Furthermore, we made it clear that the efficiency of cleavage of O-glycan differed between Ser and Thr residue.

Free Research Field

分析化学

Academic Significance and Societal Importance of the Research Achievements

本研究でのシアル酸の構造上の識別法、スレオニン残基修飾糖鎖の切断法、そしてマイケル付加反応の効率についての研究により、これまでに詳細な情報がなく、本研究の成果が糖タンパク質に関連する診断マーカー探索研究や糖鎖付加部位さらにはキャリアタンパク質を同定するために重要な情報取得に繋がる。