A self-lysis pathway that enhances the virulence of a pathogenic bacterium

Significance The programmed cell death (PCD) of mammalian cells plays important roles in fighting bacterial infections. Relatively little is known about the adaptive role of PCD in bacteria. Here we report the discovery of a potential PCD pathway in Pseudomonas aeruginosa . We show that activation of the system can occur in a subset of cells in response to DNA damage through cleavage of an essential transcription regulator that controls a cell lysis program. Although this is lethal to the individual cell in which it occurs, we find that PCD enhances the ability of the bacterium to cause disease. Our findings suggest that PCD is a strategy used by both host and pathogen to promote survival during an infection.