An essential step in the life cycle of many important pathogenic bacteria is their ability to invade cells that are normally nonphagocytic. Gaining access to an intracellular niche provides bacteria with an environment permissive for growth, allows them to avoid host defense mechanisms, or permits them to gain access to deeper tissues. Listeria monocytogenes is a food-borne intracellular pathogen that, although most often not life-threatening, can occasionally cause serious listeria infections in immunosuppressed individuals, pregnant women, and neonates (Ref.1). Critical for the development of a systemic infection is the ability of this bacterium to be internalized by both professional phagocytes and nonphagocytic cells. It is the ability of these bacteria to invade non-phagocytic cells, plays an essential role in breaching [...]