Year-end Sale % OFF 
Abstract
Extracted arrival time distributions of negative ion CID-derived fragments produced prior to traveling-wave ion mobility separation were evaluated for their ability to provide structural information on N-linked glycans. Fragmentation of high-mannose glycans released from several glycoproteins, including those from viral sources, provided over 50 fragments, many of which gave unique collisional cross-sections and provided additional information used to assign structural isomers. For example, cross-ring fragments arising from cleavage of the reducing terminal GlcNAc residue on Man8GlcNAc2 isomers have unique collision cross-sections enabling isomers to be differentiated in mixtures. Specific fragment collision cross-sections enabled identification of glycans, the antennae of which terminated in the antigenic α-galactose residue, and ions defining the composition of the 6-antenna of several of the glycans were also found to have different cross-sections from isomeric ions produced in the same spectra. Potential mechanisms for the formation of the various ions are discussed and the estimated collisional cross-sections are tabulated.Graphical ᅟ
Highlights
N -Glycans are those carbohydrates attached to asparagine residues [1] in about half of the known proteins and are critical for many of the properties of these compounds, such as cell-cell adhesion and half-life
The high-mannose glycans are key targets in vaccine design such as those against the human immunodeficiency virus (HIV) [3, 4] where the sole target for antibody neutralisation is the glycoprotein, Env, a heavily glycosylated glycoprotein consisting of a trimer of gp120/gp41 heterodimers
This paper extends the above methods to an examination of the ability of ion mobility to extract structural information from fragments of high-mannose and other N-glycans generated from negative molecular ions produced in the trap region of a Waters traveling wave ion mobility Synapt G2Si mass spectrometer [52]
Summary
N -Glycans are those carbohydrates attached to asparagine residues [1] in about half of the known proteins and are critical for many of the properties of these compounds, such as cell-cell adhesion and half-life. All contain a chitobiose core attached to three mannose residues to which several glycan chains called antennae are attached. They are biosynthesised [2] in most species, including mammals, by attachment of the glycan Glc3Man9GlcNAc2 (15, Scheme 1) to the nascent protein followed by removal of the glucose and α-mannose residues to give Man5GlcNAc2 (2). These compounds and the intermediate glycans such as 3-14 are known as high-mannose glycans. Understanding the detailed structure of the high-mannose glycans, several of which occur as isomers, has prompted increased interest in methods for their analysis
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of the American Society for Mass Spectrometry
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
