Neutral loss of isocyanic acid in peptide CID spectra: a novel diagnostic marker for mass spectrometric identification of protein citrullination.
J Am Soc Mass Spectrom
; 20(4): 723-7, 2009 Apr.
Article
en En
| MEDLINE
| ID: mdl-19200748
ABSTRACT
Protein citrullination is emerging as an important signaling mechanism that modulates a variety of biological processes. This protein modification constitutes only a 1 Da mass shift, and can be readily confused with other common protein modifications that yield an identical mass shift. In an attempt to develop a robust methodology for detection of protein citrullination sites, we analyzed synthetic citrulline-containing peptides by electrospray ionization tandem mass spectrometry. Collision-induced dissociation (CID) spectra revealed abundant neutral loss of 43 Da from citrullinated peptide precursor ions, which was reconciled by elimination of the HNCO moiety (isocyanic acid) from the citrulline ureido group. The elimination occurs readily in multiple charge states of precursor ions and also in b and y ions. HNCO loss in CID spectra provides a novel diagnostic marker for citrullination, and its utility was demonstrated by the discovery of Arg197 as the specific site of citrullination on nucleophosmin upon peptidylarginine deiminase 4 treatment.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Péptidos
/
Cromatografía Liquida
/
Citrulina
/
Cianatos
/
Espectrometría de Masas en Tándem
Tipo de estudio:
Diagnostic_studies
Límite:
Humans
Idioma:
En
Revista:
J Am Soc Mass Spectrom
Año:
2009
Tipo del documento:
Article
País de afiliación:
Estados Unidos