Mapping the Interactions and Dynamics that Organize Bacteria Cells

Project Summary Molecular-scale interactions enable subcellular organization, but the current state-of-the-art does not include a generalizable method for measuring how molecules move and cooperate on the nanometer scale and in real time within the cell. This gap is particularly striking in bacteria cells. Accordingly, our picture of the organization of the bacterial cell is incomplete. This proposal aims to understand how cellular components organize—by scaffolding, aggregation, phase separation, or otherwise—to produce a general model of bacterial cell organization and ultimately enable us to promote commensal bacteria or fight human disease. Thus, we aim to measure the positioning, interactions, and motions of molecules in living bacterial cells in different protein systems implicated in the sub-cellular organization of these cells. This proposal will develop these next- generation super-resolution tools through three synergistic specific aims: (1) to super-resolve how single- molecule dynamics vary in space and in time in living bacterial cells; (2) to super-resolve sub-cellular interactions in space and time in living bacteria cells; and (3) to improve the detection of single molecules in living bacteria cells. The toolkit that we develop to map molecular motions and interactions will be broadly applicable to the single-molecule bacteriology community. Furthermore, by focusing on applications in bacterial cell biology, the tools developed in this project will have a widespread, positive biomedical impact by making accessible long- term, significant questions in microbial biology.