Oral Sessions (Day1, Day2, Day3)
Poster Presentations
- Day 3, May 21（Fri.） Room P2 (Zoom)
-
3P-48 PDF
Functional evaluation of endo- and exo-type glycosidases and O-glycopeptidases via fluorescence detection and mass spectrometry
O-Glycans are important for the structure, folding, stability, recognition, expression, and processing of proteins. Many studies have been performed to elucidate the biological and clinical significance of altered O-glycosylation. However, lack of established methodology, absence of consensus motif for mucin-type O-glycosylation and complex O-glycan structures make O-glycoproteomics difficult. To overcome these analytical difficulties, two recent MS/MS activation methods and selective enrichment of O-glycopeptide have been developed. The former are electron capture dissociation (ECD) and electron transfer dissociation (ETD), which enables both the identification of the modified peptide sequence and the assignment of the site of modification. The latter is achieved by using O-glycan-recognizing proteins (lectins or glycosidases) or proteases (O-glycoproteases) that act only on glycopeptides with O-glycans from the complex sample. We have obtained several kinds of O-glycopeptides from commercial whey protein products in the previous study [1]. Here, their O-glycopeptides were subjected to highly sensitive fluorescent labeling capable of MS detection. As the result, the behavior of labeled O-glycopeptides for glycosidases or O-glycopeptidases could be traced using both fluorescence detection and MS detection, and the substrate specificity of endo- and exo-type glycosidases and O-glycopeptidases could be evaluated.