BetaH proteolysis unleashes an electrostatic-homing antibacterial polymorphic toxin.

ABSTRACT: Contact-dependent or diffusible proteinaceous polymorphic toxin systems (PTSs) mediate widespread bacterial competition. While bioinformatic analyses have identified diverse PTSs across bacterial phyla, experimental validation in Gram-positive species remains limited. Here, we characterize a diffusible PTS encoded by the Staphylococcus aureus S8-Ntox35 locus. We demonstrate that this system mediates inter-genus antagonism against Listeria monocytogenes via a bactericidal, heat-labile protein, and that toxicity depends on extracellular cleavage of the BetaH domain by an S8 peptidase. This processed peptide resembles a cationic antimicrobial peptide (CAMP) and facilitates intoxication of target cells by the Ntox35 RNase domain. Target cell resistance is impacted by known CAMP d

SUBMITTER: Mwangi D 

PROVIDER: S-EPMC12330581 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature