Proteomics Tools

Peptide Retention Notation

Peptide fragmentation notation using the scheme of Roepstorff and Fohlman (1984). Peptide fragment ions are indicated by a, b, or c if the charge is retained on the N-terminus and by x, y or z if the charge is maintained on the C-terminus. The subscript indicates the number of amino acid residues in the fragment.

Roepstorff P, Fohlman J (1984). “Proposal for a common nomenclature for sequence ions in mass spectra of peptides”. Biomed. Mass Spectrom. 11 (11): 601. DOI:10.1002/bms.1200111109.