Figure 5.

MALDI-TOF-MS analysis of H4 and H3 peptides. Deacetylation of fully acetylated H4 (A) and H3 (B) peptides reveals that at least one additional site of deacetylation is present in each peptide as compared with cHPLC-MS/MS analysis. The MALDI-TOF-MS data was calibrated externally using standard peptides. Mass of the deacetylated peptides is as indicated. The presence of mono-, di-, and tri-deacetylated species is indicated for each peptide. Percentage of peptide in each acetylated state is calculated as a ratio of each acetylated form compared with the total input peptide for each reaction.