METHOD FOR HIGHLY MULTIPLEXED QUANTITATION OF PEPTIDES BY MASS SPECTROMETRY AND LABELING REAGENT SETS THEREFOR

摘要

Disclosed herein are isobaric labeling reagent sets useful for multiplexed quantitation of peptides. The isobaric labeling reagent sets include a collection of at least two isobaric labeling reagents having first and second reporter groups with the same nominal mass but different isotopic substitutions and consequently different exact masses. Mass spectrometric analysis of the labeled samples is performed using a mass analyzer, such as an Orbitrap mass analyzer, capable of adequately resolving the ions of the first and second reporter groups. Reagent sets of the foregoing description may provide a degree of multiplexing in reporter ion quantitation experiments that is expanded relative to conventional labeling reagent sets, thereby reducing the number of chromatographic runs required for analysis and improving sample throughput.

主权项

1. An isobaric labeling reagent set for use in quantitative measurement of peptides by mass spectrometry, comprising:
a plurality of different isobaric labeling reagents, each reagent comprising a reporter group, a mass normalizing group, a peptide-reactive group, and a cleavable linker attaching the reporter group to the mass normalizing group, each one of the plurality of isobaric labeling reagents having the same nominal mass; each one of the isobaric labeling reagents having a reporter group with a mass different from the masses of the reporter groups of each of the other isobaric labeling reagents, each reporter group having the same elemental composition; wherein a first collection of at least two of the isobaric labeling reagents have reporter groups of the same nominal mass but different exact mass by having different numbers of at least one of 13C, 15N and 2H substitutions.