Frank Lee Rose Hills
Extracellular Electron Transport in Listeria monocytogenes
Listeria monocytogenes is a Gram-positive pathogenic bacterium that causes the foodborne illness Listeriosis in humans. The Portnoy lab discovered that L. monocytogenes has the ability to do extracellular electron transfer (EET), which consists of transferring electrons from the inside of the bacteria to extracellular acceptors outside, using compounds called flavins. This process allows L. monocytogenes to grow on non-fermentable carbon sources, and strains lacking EET activity have been shown to have reduced viability in vivo. I will be studying the role of two proteins discovered to be essential for EET activity, EetA and EetB. Details of EET activity in L. monocytogenes have been largely unknown, perhaps due to the fact that L. monocytogenes lacks the conventional life cycle and genes common in other bacterium capable of doing EET. My project aims to expand our limited knowledge of EET by identifying the role of EetA/EetB in this process. By better understanding the specific mechanics of EET, we can better understand L. monocytogenes metabolism and how it might be contributing to its pathogenesis in humans.