Improving peptide fragmentation by N‐terminal derivatization with high proton affinity
peer-reviewed · Rapid Communications in Mass Spectrometry · 2011
| Date | 2011-05-15 |
| Type | peer-reviewed |
| Venue | Rapid Communications in Mass Spectrometry |
| Publisher | Wiley |
| Contribution | adjacent |
| DOI | 10.1002/rcm.4962 |
| Citations (OpenAlex) | 22 |
| Venue 2-year citedness | 1.80 |
Abstract
An improved method of de novo peptide sequencing based on mass spectrometry using novel N-terminal derivatization reagents with high proton affinity has been developed. The introduction of a positively charged group into the N-terminal amino group of a peptide is known to enhance the relative intensity of b-ions in product ion spectra, allowing the easy interpretation of the spectra. However, the physicochemical properties of charge derivatization reagents required for efficient fragmentation remain unclear. In this study, we prepared several derivatization reagents with high proton affinity, which are thought to be appropriate for peptide fragmentation under low-energy collision-induced dissociation (CID) conditions, and examined their usefulness in de novo peptide sequencing. Comparison of the effects on fragmentation among three derivatization reagents having a guanidino or an amidino moiety, which differ in proton affinity, clearly indicated that there was an optimal proton affinity for efficient fragmentation of peptides. Among reagents tested in this study, derivatization with 4-amidinobenzoic acid brought about the most effective fragmentation. This derivatization approach will offer a novel de novo peptide sequencing method under low-energy CID conditions.
Methods and tools
- High proton affinity N-terminal derivatization: Guanidino and amidino N-terminal derivatization reagents that strengthen b-ion series under low-energy CID for easier de novo sequencing.