Fig. 2
From: Evaluation of open search methods based on theoretical mass spectra comparison
MS/MS spectra matches and their peptide sequences. b-ions are displayed in blue, y-ions in red, and matches between spectra in dashed lines. Intensities of all peaks are set to an arbitrary unit value in theoretical spectra. The EAEDISEK MS/MS spectrum (in the middle) shares 7 masses (black dashed lines) with the native EAEISEK spectrum (above). After a shift of \(\Delta m\) at position 3 in EAEISEK (below), 8 new masses match with EAEDISEK (as shown in green), and one match is removed (grey dashed line). The SPC is then improved from 7 (raw SPC) to 14 (shift SPC)