Deuterium Isobaric Amine-Reactive Tags for Quantitative Proteomics

This paper demonstrates the applications of a novel isobaric reagent, named deuterium (H-2) isobaric amine-reactive tag (DiART), for quantitative proteomics. Peptides labeled with DiART were analyzed using an electrospray ionization (ESI)-based LTQ-Orbitrap mass spectrometer. Our data showed that H-2-associated isotope effects, such as partial loss of H-2 labels during tandem mass spectrometry (MS/MS) and H-2-related chromatographic shift, were either not observed or negligible. With the use of a hybrid collision-induced dissociation (CID) higher energy C-trap dissociation (HCD) acquisition method, we were able to identify DiART-labeled peptides with high confidence and quantify them with high accuracy. Furthermore, we adopted a hybrid electron-transfer dissociation (ETD)-HCD acquisition protocol and developed a novel data analysis approach to measure phosphorylation of peptides. Our results showed DiART had excellent performance on LTQ-Orbitrap instruments and provided a cost-effective technique for large-scale quantitative proteomics measurements.