Differentiation between peptides containing acetylated or tri-methylated lysines by mass spectrometry: an application for determining lysine 9 acetylation and methylation of histone H3.

Histone acetylation and methylation play a critical role in transcription and gene regulation. Identification of sites of lysine acetylation and methylation in histones or other proteins by mass spectrometry (MS) is of increasing interest. In this paper, we report the use of MS to differentiate between peptides containing acetylated or tri-methylated lysines.