PROJECT SUMMARY Quorum sensing is a method of cell-cell communication used by bacteria to detect and respond to changes in population density and control behaviors that benefit the group for adaption and survival in their environment (e.g., symbiosis and pathogenesis). My research program is focused on how bacteria use quorum sensing signaling to control expression of virulence genes. Toward this goal, we study quorum sensing gene regulation in Vibrio species, both as relevant pathogens and as established quorum sensing model systems. We focus on the master Vibrio quorum sensing transcription factor LuxR, which is conserved in all Vibrio species and is the core regulator of hundreds of genes. My research group uses biochemical, biophysical, molecular biology, and physiological assays to dissect the LuxR mechanisms of regulation in multiple Vibrio species. These experiments are the foundational components of my research program. We routinely perform assays that require a standard refrigerated superspeed centrifuge: DNA isolation, cell washing, competent cell preparations, protein purification, and protein concentration. I am requesting funds to purchase a Sorvall Lynx 6000 superspeed refrigerated centrifuge and rotors. Purchase of the Sorvall Lynx will expand my lab’s repertoire of assays, increase our productivity, replace old and failing equipment, and eliminate costs for repairs of our current under-performing tabletop centrifuge. We will improve our current biochemical assays with increased throughput by expanding our ability to pellet cells in larger volumes and at higher speeds. A new, reliable centrifuge with larger capacity will ensure that our lab can continue its high level of productivity without the frequent repairs and down-time of our existing centrifuge.