中央研究院 生物化學研究所

Delineating multiple N- and O-glycosylation sites on single glycopeptides and deriving more glycan structure information to discriminate isomeric glycoforms are practical problems to be tackled. Negative mode MS²/MS³ fragmentation was investigated and developed to supplement current nanoLC-MS²-based sequencing and identification of intact glycopeptides largely performed in positive mode. We found that sulfation and sialylation drastically alter the MS² fragmentation pattern of glycopeptides in negative mode and the characteristic features identified can be utilized to program the MS³ on the glycan moiety itself. Direct elimination of one or more O-glycans affords an easy way to discover additional O-glycosylations on a multiply glycosylated peptide by virtue of enumerating the dehydration scars imprinted on the O-glycosylated sites. Moreover, the characteristic peptide core ion can be relied upon to filter out all related N-glycopeptides carrying additional O-glycans. Such enhanced ability is anticipated to have a significant impact in glycoproteomic applications.

論文名稱：“Strategic applications of negative mode LC-MS/MS analyses to expedite confident mass spectrometry-based identification of multiple glycosylated peptides”

論文網站：https://doi.org/10.1021/acs.analchem.0c00236

作者群：Chu-Wei Kuo, Kay-Hooi Khoo

更新時間：2020.06.03