Elucidating Novel Cyclic Nucleotide Signaling Pathways and Physiological Effects in Bacteria

PROJECT SUMMARY / ABSTRACT Bacteria utilize numerous sensing and signaling pathways to alter behaviors that allow host colonization of both bacterial infections and microbiomes. Bacteria translate changes in the extracellular environmental into intracellular signals, such as nucleotide-based signaling molecules, to rapidly respond and optimize physiology for survival. Understanding these signaling pathways is necessary to be able to predict bacterial behavior under different conditions and to rationally develop new methods to alter medically relevant bacterial phenotypes. Recently, we have identified roles for atypical nucleotide signals, 2’,3’-cyclic nucleotide monophosphates (2’,3’- cNMPs), in controlling transcription, translation, biofilm formation, and stress resistance in E. coli and Salmonella enterica. This research program will elucidate the molecular mechanisms that control 2’,3’-cNMP-dependent effects, the intersection with paradigmatic nucleotide-based signaling pathways, and the broad physiological effects of 2’,3’-cNMP signaling. To do so, we will synthesize chemical tools and use a variety of in vitro and in cellulo techniques to interrogate the effects of 2’,3’-cNMPs in bacterial transcription, translation, signaling pathways, and phenotypes in E. coli. In addition, we will use biochemical and genetic assays to identify metabolic enzymes and binding partners. Results from E. coli will be extended into other bacterial species to understand the conservation and diversity of 2’,3’-cNMP signaling, as well as determine the potential for targeting 2’,3’-cNMP pathways for development of new antibiotics. Ultimately, this program will provide novel insights into the cellular roles of 2’,3’-cNMP signaling in bacteria, as well as develop (bio)chemical tools and fundamental knowledge that can be applied to investigate 2’,3’-cNMP signaling in other organisms.