Molecular mechanisms powering a bacterial toxin injection device. (360G-Wellcome-104634_Z_14_Z)

Proteins are large, complex molecules that play critical roles in living organisms. They do most of the work inside cells and are required for their structure, function and regulation. Understanding how proteins are transported to specific places within cells is a key concern of modern biology. This delivery process is carried out based on information contained in the protein. We study tiny injection-type protein targeting devices, which are the principle means of the interaction of many microbe s, called bacteria, with animal or plant hosts. These apparatuses serve to inject bacterial protein toxins into host cells to manipulate them during infection. This involves the proteins passing across three biological lipid membranes (two from the bacterium and one from the host cell). We will perform a thorough biochemical, functional and structural study of the central protein secretion machinery of these systems, located in the bacterial inner membrane. Insight into this complex process coul d be used to develop a new type of anti-microbial drug to assist in the fight against infectious diseases.