Session: Session 4
Non-enzymatic acetylation in Acinetobacter baumannii
Intoduction: Acinetobacter baumannii is an opportunistic pathogen classified by the WHO as one of the three pathogens causing the most threat to public health. Indeed, with the rise of emergence of carbapenem-resistant and multidrug resistant strains, the search for new antibacterial and antibiofilm agents against A. baumannii is crucial. The persistence of this pathogen is due to its ability to form biofilms and adapt quickly to extreme conditions, by using several molecular mechanisms including post-translational modifications (PTMs).
Lysine acetylation is a widespread PTM in bacteria, that can be added through two distinct mechanisms: non-enzymatic, through direct addition of acetyl groups mainly from the donor acetyl-phosphate (AcP) produced by the enzyme phosphate-acetyltransferase Pta ; and enzymatic, through the action of lysine acetyltransferases (KATs). Enzymatic acetylation was already studied, and its importance on A. baumannii physiology was demonstrated through excess acetylation after deletion of KDACs (data not shown). Non-enzymatic acetylation was shown to impact central metabolism and translation in some bacteria, but to date no study in A. baumannii was carried out.
Methodology: The aim of this study is to characterize proteins acetylated by the addition of AcP. First, the knock-out mutant Δpta was constructed in A. baumannii strain ATCC 17978. We then compared the acetylome of the wild-type and mutant strains by using high-throughput proteomic approach coupling immunoaffinity and mass spectrometry.
Results: Proteomic data showed that proteins undergoing chemical acetylation belong to different functional categories such as translation, lipid and nucleotide metabolism, PTMs, cell wall biogenesis and signal transduction mechanisms.
Conclusion: We will discuss on proteins acetylated by the addition of AcP, focusing on a few proteins involved in interesting biological processes.
Lysine acetylation is a widespread PTM in bacteria, that can be added through two distinct mechanisms: non-enzymatic, through direct addition of acetyl groups mainly from the donor acetyl-phosphate (AcP) produced by the enzyme phosphate-acetyltransferase Pta ; and enzymatic, through the action of lysine acetyltransferases (KATs). Enzymatic acetylation was already studied, and its importance on A. baumannii physiology was demonstrated through excess acetylation after deletion of KDACs (data not shown). Non-enzymatic acetylation was shown to impact central metabolism and translation in some bacteria, but to date no study in A. baumannii was carried out.
Methodology: The aim of this study is to characterize proteins acetylated by the addition of AcP. First, the knock-out mutant Δpta was constructed in A. baumannii strain ATCC 17978. We then compared the acetylome of the wild-type and mutant strains by using high-throughput proteomic approach coupling immunoaffinity and mass spectrometry.
Results: Proteomic data showed that proteins undergoing chemical acetylation belong to different functional categories such as translation, lipid and nucleotide metabolism, PTMs, cell wall biogenesis and signal transduction mechanisms.
Conclusion: We will discuss on proteins acetylated by the addition of AcP, focusing on a few proteins involved in interesting biological processes.