Exploration of Small Molecule Signal-Meditated Interactions Among Antibiotic Producing Streptomyces

Small molecule signals are known to mediate complex behaviors in bacteria, including pathogenesis, virulence, biofilm formation and secondary metabolite production. However, little is known about the ecological roles of signaling molecules with respect to inter-species communication of soil-dwelling microbes. As part of our work to understand the structural diversity and potential functions of signaling molecules, we have focused on signaling networks among members of the Streptomyces genus of bacteria. An antibiotic overlay assay was used to identify several isolates that induced the production of inhibitory compounds through signaling interactions. Here we present our work towards characterizing the signaling molecules and the compounds responsible for enhanced antimicrobial activity. Our ongoing work may have important implications towards the discovery of new therapeutic secondary metabolites by targeting signal-mediated antibiotic production. In addition, understanding signal-mediated processes may provide insight into ecological interactions among microbial communities and lead to improved strategies of biological control using microbial isolates in agriculture soils.