loading page

N-terminal chemical derivatization of peptides with 4-formyl-benzenesulfonic acid under charge reduction conditions and electrospray positive and negative tandem mass spectrometry de novo sequencing
  • +4
  • Luka Ozdanovac,
  • Lucija Dončević,
  • Amela Hozić,
  • Renata Biba,
  • Ema Svetličić,
  • Andrea Janeš,
  • Mario Cindrić
Luka Ozdanovac
Ruđer Bošković Institute
Author Profile
Lucija Dončević
Ruđer Bošković Institute
Author Profile
Amela Hozić
Ruđer Bošković Institute
Author Profile
Renata Biba
Ruđer Bošković Institute
Author Profile
Ema Svetličić
Technical University of Denmark
Author Profile
Andrea Janeš
Clinical hospital "Sveti Duh"
Author Profile
Mario Cindrić
Ruđer Bošković Institute

Corresponding Author:[email protected]

Author Profile


RATIONALE: Selective derivatization of peptide N-terminus with 4-formyl-benzenesulfonic acid (FBSA) enables chemically activated fragmentation in ESI+/- (positive and negative ion mode) under charge reduction conditions. Overlapped positive and negative tandem mass spectra pinpoint b-ions making the assignment of b-ion series fragments easy and accurate. METHODS: We developed a FBSA-peptide microwave assisted derivatization procedure. Derivatized and non-derivatized bovine serum albumin tryptic peptides and insulin non-tryptic peptide were compared after MS/MS analysis in positive and negative ion mode. High-quality dataset of sulfonated b-ions obtained in negative tandem mass spectra of singly charged FBSA-peptides were matched to detected b-ions in positive MS/MS spectra. Moreover, negative spectra signals were converted and matched against y-ions in positive tandem mass spectra to identify complete peptide sequences. RESULTS: The FBSA derivatization procedure produced a significantly improved MS/MS dataset (populated by high-intensity signals of b- and y-ions) in comparison to commonly used N-terminal sulfonation reagents. Undesired side reactions do not occur and the procedure reduces the derivatization time. It was found that b-ions comprise 15% and 13% of all fragment ions generated in positive and negative ion mode, respectively. High visibility of b-ion series in negative ion mode can be attributed to the N-terminal sulfonation which had no effect on the production of b-ion series in positive ion mode. CONCLUSIONS: The FBSA derivatization and de novo sequencing approach outlined here provides a reliable method for accurate peptide sequence assignment. Increased production of the b-ions in positive and negative ion mode greatly improves peak assignment and thus enables accurate sequence reconstruction. Implementation of the named methodology would improve the quality of de novo sequencing data and reduce the number of misinterpreted spectra.
17 Jan 2023Submitted to Rapid Communications in Mass Spectrometry
17 Jan 2023Submission Checks Completed
17 Jan 2023Assigned to Editor
17 Jan 2023Review(s) Completed, Editorial Evaluation Pending
30 Jan 2023Reviewer(s) Assigned
24 Feb 2023Editorial Decision: Revise Major
24 Mar 20231st Revision Received
26 Mar 2023Submission Checks Completed
26 Mar 2023Assigned to Editor
26 Mar 2023Review(s) Completed, Editorial Evaluation Pending
10 Apr 2023Reviewer(s) Assigned
01 May 2023Editorial Decision: Accept