High-Resolution Lysine Acetylome Profiling by Offline Fractionation and Immunoprecipitation

Acetylation of lysine side chains at their ε-amino group is a reversible posttranslational modification (PTM), which can affect diverse protein functions. Lysine acetylation was first described on histones, and nowadays gains more and more attention due to its more general occurrence in proteomes, and its possible crosstalk with other protein modifications. Here we describe a workflow to investigate the acetylation of lysine-containing peptides on a large scale. For this high-resolution lysine acetylome analysis, dimethyl-labeled peptide samples are pooled and offline-fractionated using hydrophilic interaction liquid chromatography (HILIC). The offline fractionation is followed by an immunoprecipitation and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for data acquisition and subsequent data analysis.