Collisional Activation Dissociation Mass Spectrometry Studies of Oligosaccharides Conjugated with Na+-Encapsulated Dibenzo-18-Crown-6 Ether

Hwangbo Song,Bongjin Moon,Han Bin Oh,Jungeun Bae

doi:10.5478/msl.2016.7.4.96

Abstract

To determine the influence of the cationization agent on the collision activated dissociation (CAD) fragmentation behavior of oligosaccharides, the CAD spectra of the singly protonated, sodiated oligosaccharides and singly sodiated and dibenzo-18-crown-6 ether conjugated oligosaccharides were carefully compared. Each of these three different species showed quite different fragmentation spectra. The comparison of singly protonated and sodiated oligosaccharide CAD spectra revealed that different cationization agents affected the cationization agent adduction sites as well as the fragmentation sites within the oligosaccharides. When the mobility of Na+ was limited by the dibenzo-18-crown-6 ether encapsulation agent, the examined linear oligosaccharides showed fragmentation patterns quite different from the unmodified ones. For the dibenzo-18-crown-6 ether conjugated oligosaccharides, the charge-remote fragmentation pathways were more likely to be activated than the chargedirected pathways. This work demonstrates that dibenzo-18-crown-6 ether conjugation can potentially provide a route to selectively activate the charge-remote fragmentation pathways, albeit to a limited extent, in tandem mass spectrometry studies.

Highlights

Glycosylation is one of the most common posttranslational modifications
The comparison of singly protonated and sodiated oligosaccharide collision activated dissociation (CAD) spectra revealed that different cationization agents affected the cationization agent adduction sites as well as the fragmentation sites within the oligosaccharides
It is shown that the protonated oligosaccharides tend to induce a much simpler fragmentation pattern, mostly with B series fragments, while Na+ cationized oligosaccharides show Y series fragments along with B series products

Summary

Introduction

Glycosylation is one of the most common posttranslational modifications. In the framework of glycosylated proteins, glycans play an important role in a variety of biological processes, such as protein conformation, cell signaling, cell adhesion, and cell recognition.[1]. These spectra clearly indicate that the fragmentation patterns are quite different, consistent with previous literature reports.[16,18,19] For the protonated maltose ions, a peak originating from OH loss is dominant, followed by glycosidic bond cleavage products such as B1 and Y1.

Results

Conclusion