
mBio, Journal Year: 2025, Volume and Issue: unknown
Published: April 30, 2025
ABSTRACT Listeria monocytogenes (Lm ) is a Gram-positive, facultative intracellular pathogen that uses both housekeeping (P1) and stress-activated (Sigma B-dependent) promoter (P2) to express the master virulence regulator PrfA. The Sigma B regulon contains over 300 genes known respond different stressors. However, role of in regulation prfA during infection remains uncertain. To define pathways lead B-dependent activation, we performed genetic screen L2 fibroblasts using ΔP1 Lm only has directly upstream . identified transposon insertions large bacterial sensory organelle as stressosome. absence functional stressosome components resulted heterogeneity within populations, with some bacteria behaving like wild type, while other members population exhibited defects either vacuolar escape and/or cell-to-cell spread. We show mutants cannot be rescued by constitutive activation These data defined importance controlling homogeneity characterized function robust infection. model provides new opportunities identify host-specific signals necessary for stressosome-dependent signaling pathogenesis. IMPORTANCE Microbial pathogens must adapt varying levels stress survive. This study uncovered link between sensing program pathogen, host-imposed sensed machinery ensure resilient responses vivo Stressosome-dependent PrfA was maintain L. transition early late stages work also further characterize how specific stimuli affect survival host , which critical our understanding
Language: Английский