Improved peptide sequencing using isotope information inherent in tandem mass spectra
peer-reviewed · Rapid Communications in Mass Spectrometry · 2003
peer-reviewed · Rapid Communications in Mass Spectrometry · 2003. W.R. Cannon et al. We demonstrate here the use of natural isotopic ‘labels’ in peptides to aid in the identification of peptides…
| Date | 2003-08-15 |
| Type | peer-reviewed |
| Venue | Rapid Communications in Mass Spectrometry |
| Publisher | Wiley |
| Contribution | algorithm |
| DOI | 10.1002/rcm.1119 |
| Citations (OpenAlex) | 22 |
| Venue 2-year citedness | 1.80 |
Abstract
We demonstrate here the use of natural isotopic ‘labels’ in peptides to aid in the identification of peptides with a de novo algorithm. Using data from ion trap tandem mass spectrometric (MS/MS) analysis of 102 tryptic peptides, we have analyzed multiple series of peaks within LCQ MS/MS spectra that ‘spell’ peptide sequences. Isotopic peaks from naturally abundant isotopes are particularly prominent even after peak centroiding on y- and b-series ions and lead to increased confidence in the identification of the precursor peptides. Sequence analysis of the MS/MS data is accomplished by finding sequences and subsequences in a hierarchical manner within the spectra.
Methods and tools
- Hierarchical subsequence de novo scoring (PNNL): PNNL de novo approach that finds sequences and subsequences hierarchically in a reduced spectrum graph, using multiple ion series and natural isotope peaks, and ranks candidates by the probability of random matches.