Figure 6.

LC/MS/MS spectra of peptides identified in the eEF1A26 isoform. eEF1A26 was purified by HPLC and digested with trypsin, Glu-C, and Asp-N proteases, as described in “Materials and Methods,” and the digestion products were analyzed by LC/MS/MS. Identification of the peptides and posttranslational modifications were conducted by comparison of the fragmentation patterns of individual peptides with those predicted from protein databases using SEQUEST. A, LC/MS/MS spectrum of a Glu-C derived peptide trimethylated at a Lys residue. B, LC/MS/MS spectrum of a tryptic peptide phosphorylated at a Ser residue. C, LC/MS/MS spectrum of a tryptic peptide monomethylated at a Lys residue.