Toxin-antitoxin (TA) systems are genetic modules that consist of a stable protein-toxin and an unstable antitoxin that neutralizes the toxic effect. In type II TA systems, the antitoxin is a protein that inhibits the toxin by direct binding. Type II TA systems, whose roles and functions are under intensive study, are highly distributed among bacterial chromosomes. Here, we identified and characterized a novel type II TA system encoded in the chromosome of the clinical isolate 39016 of the opportunistic pathogen Pseudomonas aeruginosa. We have shown that the system exhibits classical type II TA characteristics and novel regulatory properties. We also found that the system is involved in biofilm and motility regulation. Importantly, we found that the prrA deletion significantly reduced prophage induction and bacteriophage production in the 39016 strain. Hence, we named the system PrrT/A for Prophage Regulator Toxin/Antitoxin. We reveal that a chromosome-encoded TA system can regulate prophage gene expression and phage production, which presents a thus far undiscovered function of bacterial TA systems.

Toxin-antitoxin (TA) systems are genetic modules that consist of a stable protein-toxin and an unstable antitoxin that neutralizes the toxic effect. In type II TA systems, the antitoxin is a protein that inhibits the toxin by direct binding. Type II TA systems, whose roles and functions are under intensive study, are highly distributed among bacterial chromosomes. Here, we identified and characterized a novel type II TA system encoded in the chromosome of the clinical isolate 39016 of the opportunistic pathogen _Pseudomonas aeruginosa_. We have shown that the system exhibits classical type II TA characteristics and novel regulatory properties. We also found that the system is involved in biofilm and motility regulation. Importantly, we found that the _prrA_ deletion significantly reduced prophage induction and bacteriophage production in the 39016 strain. Hence, we named the system PrrT/A for Prophage Regulator Toxin/Antitoxin. We reveal that a chromosome-encoded TA system can regulate prophage gene expression and phage production, which presents a thus far undiscovered function of bacterial TA systems.

PrrT/A a Pseudomonas aeruginosa Bacterial Encoded Toxin-Antitoxin System Involved in Prophage Regulation

Exploring the intricacies of host-pathogen communication is vital in order to understand why
some microbes persist within a host, while others are effectively cleared. As such,
host-pathogen communication is an urgent area of research underpinning human health
and disease, especially given the emerging concerns of antibiotic resistance.
Understanding host-pathogen pathways requires intricate knowledge in the fields of both
microbiology and immunology.

Living in a world of specialists, where scientists sometimes invest their whole career
studying one organism, a specific pathway or a protein, multidisciplinary discussions of
host-pathogen interactions are highly needed. This international conference will provide
such a forum for scientific exchange at the highest level, between scientists from different
research areas related to host-pathogen interactions, with the aim to trigger fruitful
collaborations addressing the urgent questions in the field.

This meeting has an additional special focus of bringing researchers from Ireland, Denmark
and Israel together to learn about cutting edge biology and form new collaborations.
Thus, the conference will be a showcase for the exciting and original research emanating
from these three small but innovative countries.