Life is about interactions. One of them is the interaction between bacteria and a host, which we study.

The bacteria-host interaction can be beneficial for both (mutualistic interaction), or can occur without any harm or benefit for the host but be beneficial for the bacteria (commensal relationship). Alternatively, the interaction can be harmful to the host but beneficial for the bacteria (pathogenic or parasitic interaction).

The secretion systems allow bacteria to interact with the environment and modify the milieu. Our current research projects focus on the type III effector proteins that are produced by bacteria and are injected into the host cell by a bacterial syringe-like apparatus, known as the type III secretion system (T3SS).   

The T3SS injectisome is a sophisticated protein-export apparatus that enables the delivery of the type III effector proteins from bacterial cytosol into the cell cytosol through a conduit spanning the two bacterial membranes and the plasma membrane of the target cell. It consists of an extracellular needle-like appendage, which protrudes from the bacterial surface and is linked to a cell wall-embedded secretion system machinery steered by the associated cytoplasmic components.

The specific role of T3SS in bacterial pathogenesis is directed by its expression & assembly and the repertoire of the translocated type III effector proteins, which manipulate host cell signaling pathways and defense. We unravel how type III effector proteins act inside host cells and what are the details and functional consequences of their interactions and/or enzymatic activities. We address these in Bordetella, Salmonella and Aeromonas species.