Kin cell lysis is a danger signal that activates antibacterial pathways of Pseudomonas aeruginosa
- University of Washington, United States
- University of Maryland, United States
Abstract
The perception and response to cellular death is an important aspect of multicellular eukaryotic life. For example, damage-associated molecular patterns activate an inflammatory cascade that leads to removal of cellular debris and promotion of healing. We demonstrate that lysis of Pseudomonas aeruginosa cells triggers a program in the remaining population that confers fitness in interspecies co-culture. We find that this program, termed P. aeruginosa response to antagonism (PARA), involves rapid deployment of antibacterial factors and is mediated by the Gac/Rsm global regulatory pathway. Type VI secretion, and, unexpectedly, conjugative type IV secretion within competing bacteria, induce P. aeruginosa lysis and activate PARA, thus providing a mechanism for the enhanced capacity of P. aeruginosa to target bacteria that elaborate these factors. Our finding that bacteria sense damaged kin and respond via a widely distributed pathway to mount a complex response raises the possibility that danger sensing is an evolutionarily conserved process.
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© 2015, LeRoux et al.
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Kin cell lysis is a danger signal that activates antibacterial pathways of Pseudomonas aeruginosa
eLife 4:e05701.
https://doi.org/10.7554/eLife.05701
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