Targeting Undiscovered Links between Quorum Sensing and Iron Chelation Among Competing and Cooperating Human Pathogens

We are trying to answer one of the most fundamental questions regarding life on Earth: how do different species figure out where they are, who is around, and what nutrients (such as the crucial element iron) are around? And, most importantly, from a human health perspective, what do they do with this information? In the absence of visual cues, microbes mostly rely on chemical signals to sense where they are and who and what is near. Knowing this would allow them to adjust their behavior and either compete With, cooperate or ignore the other species. Despite the importance of understanding these interactions, especially given the effects of microbes on human health and the environment, surprisingly little is known regarding the chemical details underlying these interactions - very few signals and sensors have been identified. In this project we will study in detail the chemical interactions between two versatile human pathogens (Pseudomonas aeruginosa and Staphylococcus aureus) that often meet one another inside and on humans, and they can cooperate to cause infections that are difficult to eradicate.