GSE210097
The RNA-binding protein PNPase regulates biofilm formation and virulence in Listeria monocytogenes
Biofilm-related diseases are typically persistent infections, and a challenge for medical treatment. Biofilms are communities of bacteria that attach to surfaces and are enclosed in an extracellular matrix. These sessile microorganisms can endure external stresses like nutrient deprivation, antibiotic treatments, and immune defences. Therefore, biofilms create conditions favourable for bacterial pathogenesis. The knowledge of novel biofilm regulators may contribute to develop new strategies to fight microbial infections. In this work we study the role of the RNA-binding protein and RNA-degradative enzyme polynucleotide phosphorylase (PNPase) from the human pathogen Listeria monocytogenes. We show that inactivation of Listeria PNPase not only leads to strong defects in biofilm production, but also affects biofilm morphology. RNA-seq analysis of the RNA extracted from biofilms of the wild-type and the PNPase mutant strains revealed major changes in the expression of genes affecting the metabolism of carbon. Lastly, infection assays in eukaryotic cell lines confirmed that PNPase deletion leads to the severe attenuation of Listeria monocytogenes pathogenicity. Overall, our results show that PNPase is a novel regulator of biofilm formation and human cellular invasion of a bacterial pathogen. This work presents PNPase as a new and attractive target for the control of bacterial infection and highlights the expanding role of RNA-binding proteins as critical players in pathogenicity. Overall design: Comparative gene expression profiling analysis of RNA-seq data for WT and PNPase deletion mutant.