Screening for eukaryotic motives in Legionella pneumophila reveals bacterial LPC_1677 as functional host histone de-acetylase

Purpose: The interaction between Legionella pneumophila and its host cell is not completly understood. The aim of this study was to identify eukaryotic-like bacterial factors which manipulate the host cell. Method: A stable overexpression of LPC_1677 was performed in THP-1 cells. The LPC_1677 overexpressing cells were infected with L.p. and RNA sequencing was performed. Key pro-inflammatory markers were validated via qPCR and ELISA. Results: Bioinformatic screening for eukaryotic-like motives in L.p. took us to LPC_1677 which deacetylates host histones and thereby attenuating gene transcription. Conclusion: This study demonstrated that the eukaryotic-like bacterial factor LPC_1677 de-acetylates Histones in the host cell. Overall design: THP-1 control cells as well as LPC_1677 overexpressing cells were infected with L.p. (MOI 1) for 3 hours or left uninfected.