Programmable acetylation modification of bacterial proteins by a Cas12a-guided acetyltransferase

ABSTRACT Protein lysine acetylation (PLA) is a crucial post-translational modification in organisms that regulates a variety of metabolic and physiological activities. Many advances have been made in PLA-related research; however, the quick and accurate identification of causal relationships between specific protein acetylation events and phenotypic outcomes at the proteome level remains unattainable due to the lack of in situ targeted modification techniques. In this study, based on the characteristics of transcription-translation coupling in bacteria, we designed and constructed an in situ targeted protein acetylation (TPA) system fusing the dCas12a protein, guiding element crRNA, and bacterial acetylase At2. Rapid identification of multiple independent protein acetylation and cell phenotypic analyses in gram-negative E. coli and gram-positive C. ljungdahlii demonstrated that TPA is a specific and efficient targeting tool for protein modification studies and engineering.