Isotope‐coded N‐terminal sulfonation of peptides allows quantitative proteomic analysis with increased de novo peptide sequencing capability
peer-reviewed · Rapid Communications in Mass Spectrometry · 2004
| Date | 2004-12-30 |
| Type | peer-reviewed |
| Venue | Rapid Communications in Mass Spectrometry |
| Publisher | Wiley |
| Contribution | algorithm |
| DOI | 10.1002/rcm.1724 |
| Citations (OpenAlex) | 43 |
| Venue 2-year citedness | 1.80 |
Abstract
Recently various methods for the N-terminal sulfonation of peptides have been developed for the mass spectrometric analyses of proteomic samples to facilitate de novo sequencing of the peptides produced. This paper describes the isotope-coded N-terminal sulfonation (ICenS) of peptides; this procedure allows both de novo peptide sequencing and quantitative proteomics to be studied simultaneously. As N-terminal sulfonation reagents, 13C-labeled 4-sulfophenyl[13C6]isothiocyanate (13C-SPITC) and unlabeled 4-sulfophenyl isothiocyanate (12C-SPITC) were synthesized. The experimental and reference peptide mixtures were derivatized independently using 13C-SPITC and 12C-SPITC and then combined to generate an isotopically labeled peptide mixture in which each isotopic pair differs in mass by 6 Da. Capillary reverse-phase liquid chromatography/tandem mass spectrometry experiments on the resulting peptide mixtures revealed several immediate advantages of ICenS in addition to the de novo sequencing capability of N-terminal sulfonation, namely, differentiation between N-terminal sulfonated peptides and unmodified peptides in mass spectra, differentiation between N- and C-terminal fragments in tandem mass spectra of multiply protonated peptides by comparing fragmentations of the isotopic pairs, and relative peptide quantification between proteome samples. We demonstrate that the combination of N-terminal sulfonation and isotope coding in the mass spectrometric analysis of proteomic samples is a viable method that overcomes many problems associated with current N-terminal sulfonation methods.
Methods and tools
- Isotope-coded N-terminal sulfonation (ICenS): Labels peptides with light or 13C6 heavy 4-sulfophenyl isothiocyanate so the same derivatization yields y-ion dominated spectra for de novo sequencing and isotope pairs for quantification.
Cites (4)
- Highly informative proteome analysis by combining improved N ‐terminal sulfonation for de novo peptide sequencing and online capillary reverse‐phase liquid chromatography/tandem mass spectrometry (2004) crossref
- Differential stable isotope labeling of peptides for quantitation and de novo sequence derivation (2001) crossref
- Quantitation and Facilitated de Novo Sequencing of Proteins by Isotopic N-Terminal Labeling of Peptides with a Fragmentation-Directing Moiety (2000) crossref
- A method for high-sensitivity peptide sequencing using postsource decay matrix-assisted laser desorption ionization mass spectrometry (1999) crossref