Alkyl Quinolone Response is dampened by .

The bacterium is an opportunistic pathogen that can cause lung, skin, wound, joint, urinary tract, and eye infections. While is known to exhibit a robust competitive response towards other bacterial species, this bacterium is frequently identified in polymicrobial infections where multiple species survive. For example, in prosthetic joint infections (PJIs), can be identified along with other pathogenic bacteria including and Here we have explored the survival and behavior of such microbes and find that readily survives culturing with while other tested species do not. In each of the tested conditions, growth remained unchanged by the presence of indicating a unique mutualistic interaction between the two species. We find that proximity leads to attenuate competitive behaviors as exemplified by reduced production of quinolone signal (PQS) and pyocyanin. Reduced alkyl quinolones is important to as it will grow in supernatant from a quinolone mutant but not P. aeruginosa wildtype in planktonic culture. The reduced pyocyanin production of is attributable to production of ornithine by , which we recapitulate by adding exogenous ornithine to monocultures. Similarly, co-culture with an ornithine-deficient strain of leads to yield near mono-culture amounts of pyocyanin. Here, we directly demonstrate how notorious pathogens such as might persist in polymicrobial infections under the influence of metabolites produced by other bacterial species.