Tags

Type your tag names separated by a space and hit enter

Collision-induced fragmentation of underivatized N-linked carbohydrates ionized by electrospray.
J Mass Spectrom. 2000 Oct; 35(10):1178-90.JM

Abstract

The electrospray mass spectra and collision-induced fragmentation of neutral N-linked glycans obtained from glycoproteins were examined with a Q-TOF mass spectrometer. The glycans were ionized most effectively as adducts of alkali metals, with lithium providing the most abundant signal and caesium the least. Singly charged ions generally gave higher ion currents than doubly charged ions. Addition of formic acid could be used to produce [M + H]+ ions, but these ions were always accompanied by abundant cone-voltage fragments. The energy required for collision-induced fragmentation was found to increase in a linear manner as a function of mass with the [M + Na]+ ions requiring about four times as much energy as the [M + H]+ ions for complete fragmentation of the molecular ions. Fragmentation of the [M + H]+ ions gave predominantly B- and Y-type glycosidic fragments whereas the [M + Na]+ and [M + Li]+ ions produced a number of additional fragments including those derived from cross-ring cleavages. Little fragmentation was observed from the [M + K]+ and [M + Rb]+ ions and the only fragment to be observed from the [M + Cs]+ ion was Cs+. The [M + Na]+ and [M + Li]+ ions from all the N-linked glycans gave abundant fragments resulting from loss of the terminal GlcNAc moiety and prominent, though weaker, ions as the result of 0,2A and 2,4A cross-ring cleavages of this residue. Most other ions were the result of successive additional losses of residues from the non-reducing terminus. This pattern was particularly prominent with glycans containing several non-reducing GlcNAc residues where successive losses of 203 u were observed. Many of the ions in the low-mass range were products of several different fragmentation routes but still provided structural information. Possibly of most diagnostic importance was an ion formed by loss of 221 u (GlcNAc molecule) from an ion that had lost the 3-antenna and the chitobiose core. This latter ion, although coincident in mass with some other 'internal' fragments, often provided additional information on the composition of the antennae. Other ions defining antenna composition were weak cross-ring fragments produced from the core branching mannose residue. Glycans containing Gal-GlcNAc residues showed successive losses of this moiety, particularly from the B-type fragments resulting from loss of the reducing-terminal GlcNAc residue. The [M + Na]+ and [M + Li]+ ions from high-mannose and hybrid glycans gave a series of ions of composition (Man)nNa/Li+ where n = 1 to the total number of glycans in the molecule, allowing these sugars to be distinguished from the more highly processed complex glycans. Other ions in the spectra of the high-mannose glycans were diagnostic of chain branching but insufficient information was available to determine their mode of formation.

Authors+Show Affiliations

Glycobiology Institute, Department of Biochemistry, Oxford, UK. dh@glycob.ox.ac.uk

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

11110090

Citation

Harvey, D J.. "Collision-induced Fragmentation of Underivatized N-linked Carbohydrates Ionized By Electrospray." Journal of Mass Spectrometry : JMS, vol. 35, no. 10, 2000, pp. 1178-90.
Harvey DJ. Collision-induced fragmentation of underivatized N-linked carbohydrates ionized by electrospray. J Mass Spectrom. 2000;35(10):1178-90.
Harvey, D. J. (2000). Collision-induced fragmentation of underivatized N-linked carbohydrates ionized by electrospray. Journal of Mass Spectrometry : JMS, 35(10), 1178-90.
Harvey DJ. Collision-induced Fragmentation of Underivatized N-linked Carbohydrates Ionized By Electrospray. J Mass Spectrom. 2000;35(10):1178-90. PubMed PMID: 11110090.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Collision-induced fragmentation of underivatized N-linked carbohydrates ionized by electrospray. A1 - Harvey,D J, PY - 2000/12/8/pubmed PY - 2006/1/13/medline PY - 2000/12/8/entrez SP - 1178 EP - 90 JF - Journal of mass spectrometry : JMS JO - J Mass Spectrom VL - 35 IS - 10 N2 - The electrospray mass spectra and collision-induced fragmentation of neutral N-linked glycans obtained from glycoproteins were examined with a Q-TOF mass spectrometer. The glycans were ionized most effectively as adducts of alkali metals, with lithium providing the most abundant signal and caesium the least. Singly charged ions generally gave higher ion currents than doubly charged ions. Addition of formic acid could be used to produce [M + H]+ ions, but these ions were always accompanied by abundant cone-voltage fragments. The energy required for collision-induced fragmentation was found to increase in a linear manner as a function of mass with the [M + Na]+ ions requiring about four times as much energy as the [M + H]+ ions for complete fragmentation of the molecular ions. Fragmentation of the [M + H]+ ions gave predominantly B- and Y-type glycosidic fragments whereas the [M + Na]+ and [M + Li]+ ions produced a number of additional fragments including those derived from cross-ring cleavages. Little fragmentation was observed from the [M + K]+ and [M + Rb]+ ions and the only fragment to be observed from the [M + Cs]+ ion was Cs+. The [M + Na]+ and [M + Li]+ ions from all the N-linked glycans gave abundant fragments resulting from loss of the terminal GlcNAc moiety and prominent, though weaker, ions as the result of 0,2A and 2,4A cross-ring cleavages of this residue. Most other ions were the result of successive additional losses of residues from the non-reducing terminus. This pattern was particularly prominent with glycans containing several non-reducing GlcNAc residues where successive losses of 203 u were observed. Many of the ions in the low-mass range were products of several different fragmentation routes but still provided structural information. Possibly of most diagnostic importance was an ion formed by loss of 221 u (GlcNAc molecule) from an ion that had lost the 3-antenna and the chitobiose core. This latter ion, although coincident in mass with some other 'internal' fragments, often provided additional information on the composition of the antennae. Other ions defining antenna composition were weak cross-ring fragments produced from the core branching mannose residue. Glycans containing Gal-GlcNAc residues showed successive losses of this moiety, particularly from the B-type fragments resulting from loss of the reducing-terminal GlcNAc residue. The [M + Na]+ and [M + Li]+ ions from high-mannose and hybrid glycans gave a series of ions of composition (Man)nNa/Li+ where n = 1 to the total number of glycans in the molecule, allowing these sugars to be distinguished from the more highly processed complex glycans. Other ions in the spectra of the high-mannose glycans were diagnostic of chain branching but insufficient information was available to determine their mode of formation. SN - 1076-5174 UR - https://www.unboundmedicine.com/medline/citation/11110090/Collision_induced_fragmentation_of_underivatized_N_linked_carbohydrates_ionized_by_electrospray_ L2 - https://doi.org/10.1002/1096-9888(200010)35:10<1178::AID-JMS46>3.0.CO;2-F DB - PRIME DP - Unbound Medicine ER -
Try the Free App:
Prime PubMed app for iOS iPhone iPad
Prime PubMed app for Android
Prime PubMed is provided
free to individuals by:
Unbound Medicine.