Acetylome/Propionylome in Mycobacterium smegmatis

Protein acylation plays important roles in bacterialpathogenesis through regulation of enzymatic activity, protein stability, nucleic acid binding ability, and protein-proteininteractions.Mycobacteria, a genus including invasive pathogens known to cause serious diseases, shapes its pathogenicity through adaptation of its energy metabolism to microenvironments encountered within mammalian hosts. In this process, acetyl-CoA and propionyl-CoA function as important intermediates. However, the function of acetyl-CoA/propionyl-CoA driven protein acylation remained to be elucidated. Herein, we systematically investigatedprotein acetylome/propionylome in the non-pathogenic Mycobacterium smegmatis through antibody-enrichment-based proteomic analysis, in which 146 acetylated sites on 121 proteins and 26 propionylated sites on 25 proteins were identified. After that, characteristicdifference of the two acylomes were elucidated through such bioinformatic methods as motif analysis, protein-proteinanalysis, Gene Ontology analysis and KEGG analysis. In addition, quantitative mass spectrometicmethod was used to evaluate the site-specific and motif-biasedcatalytic mechanism mediated by the cAMP-dependent acetyltransferase MsKat in M. smegmatis. Furthermore, we raised the possibility that both O-serine and N-lysine acetylation might co-regulated the propionyl-CoA synthetase. This study described the landscape of acetylome and propionylome in the Mycobacterium, showingunexpected role of protein acylation regulation inMycobacteria.