Skip to main content
. Author manuscript; available in PMC: 2015 Oct 30.
Published in final edited form as: Nat Protoc. 2007;2(4):933–938. doi: 10.1038/nprot.2007.106

Figure 2.

Figure 2

MS/MS spectrum of the [M+2H]2+ precursor ion from the digest of propionylated histone H3.2 taken on an LTQ-FT mass spectrometer. This peptide was determined to span residues 18–26 and was found to contain an acetylation (ac) modification on K23. Note propionyl amide groups (pr) on the unmodified K18 residue and also on the N-terminus. b and y type ions are labeled. Inset: mass spectrum of the precursor parent ion differentiates this peptide as being acetylated (+1.23 p.p.m.) and not trimethylated (−30.66 p.p.m.), as the experimental mass of the peptide is consistent with an acetylation mark.