Extended Data Figure 4. Representative MS/MS spectra from LTQ-Orbitrap used to confirm the identity of CPR-4 in UV-CM.
a, Tryptic peptides of protein band 6 in the SDS PAGE gel (Fig. 1d) were analyzed by LC-MS/MS using LTQ-Orbitrap. The amino acid sequences of peptides identified by MS/MS analysis and matched to the amino acid sequences of CPR-4 are underlined and in Red. b, The MS/MS spectra of the two peptides identified in a are shown. The assignments of the fragmented ions observed to specific amino acid residues were performed using the Scaffold 3 search engine, and the search results are shown below the MS/MS spectra. The lower case “c” indicates the carbamidomethyl-modified cysteine residue in the tryptic peptide.