In a new study published in the Journal of Biological Chemistry (JBC), researchers from the University of Notre Dame and the University of Illinois at Urbana-Champaign have found that the bacterium Pseudomonas aeruginosa, a pathogen that causes pneumonia, sepsis and other infections, communicates distress signals within a group of bacteria in response to certain antibiotics. This communication was found to vary across the colony and suggests that this bacterium may develop protective behaviors that contribute to its ability to tolerate some antibiotics.