Standards-Free Absolute Quantitation of Oxidizable Glycopeptides by Coulometric Mass Spectrometry.
J Am Soc Mass Spectrom
; 35(7): 1441-1450, 2024 Jul 03.
Article
em En
| MEDLINE
| ID: mdl-38815255
ABSTRACT
Currently, glycopeptide quantitation is mainly based on relative quantitation due to absolute quantitation requiring isotope-labeled or standard glycopeptides which may not be commercially available or are very costly and time consuming to synthesize. To address this grand challenge, coulometric mass spectrometry (CMS), based on the combination of electrochemistry (EC) and mass spectrometry (MS), was utilized to quantify electrochemically active glycopeptides without the need of using standard materials. In this study, we studied tyrosine-containing glycopeptides, NYIVGQPSS(ß-GlcNAc)TGNL-OH and NYSVPSS(ß-GlcNAc)TGNL-OH, and successfully quantified them directly with CMS with a discrepancy of less than 5% between the CMS measured amount and the theoretical amount. Taking one step further, we applied this approach to quantify glycopeptides generated from the digestion of NIST mAb, a monoclonal antibody reference material. Through HILIC column separation, five N297 glycopeptides resulting from NIST mAb tryptic digestion were successfully separated and quantified by CMS for an absolute amount without the use of any standard materials. This study indicates the potential utility of CMS for quantitative proteomics research.
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Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Oxirredução
/
Espectrometria de Massas
/
Glicopeptídeos
Idioma:
En
Revista:
J Am Soc Mass Spectrom
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Estados Unidos