Enrichment and Metaproteomic Analysis of Lysine Acetylation in Fecal Microbiome Samples

Among the various posttranslational modifications (PTMs) found in microbiome samples, lysine acetylation is known to be abundant and plays an important role in regulating microbial short-chain fatty acid (SCFA) metabolism. The latter is a crucial microbiome function that significantly impacts human intestinal health. This chapter describes a detailed protocol for lysine acetylomic profiling of microbial proteins in human fecal microbiome samples. The protocol consists of stool sample preprocessing, microbiome protein extraction and digestion, immunoaffinity enrichment of lysine acetylated peptides, and high-resolution mass spectrometry analysis for the identification and quantification of lysine-acetylated proteins.