Bacteria have a plethora of toxic proteins that they use to manipulate and kill host cells. A major interest of our department is to understand how bacteria inject these toxins into target cells. We could unravel this process for Tc toxins that are used for example by Yersinia pestis, the pathogen that causes plague. The toxins form a special complex that, using a
syringe-like mechanism, perforates the host cell and injects the deadly component into the host cell. Part of the toxin complex is stretched like an elastic band or a spring. Upon contraction the released energy enables the pushing of the channel through the membrane. Building on these results, we have been able to fully unveil the sophisticated and unique molecular mechanism through which this unusual and complicated injection system allows membrane permeation and protein translocation.
In general, our research focuses on structural and functional studies of macromolecular protein complexes. We focus on important biological questions concerning processes at or in the cell membrane, in particular toxin-mediated membrane permeation, membrane homeostasis, and membrane fusion. Furthermore, we want to understand the molecular details of muscle contraction and the dynamics of chromatin.