Type 3 Technologies (Biozentrum, University of Basel) Information

Bacteria as a versatile tool for protein delivery The investigation of protein functions and interactions is central in cell biological research. The CTI-financed project Type 3 Technologies (T3T) aims to provide a bacteria-based tool that allows the direct delivery of proteins into eukaryotic cells. A promising technology for cell biological research at the Biozentrum and beyond. Cell biological research is often hampered by the lack of appropriate methods that allow the fast, synchronized and efficient delivery of proteins into eukaryotic cells. The most widely used technique is DNA transfection ultimately leading to expression of the desired protein. This results in a heterogeneous and unsynchronized cell population after an incubation time of 12-48 hours. Hence, the protein under study is often present for far longer than physiologically relevant or desirable. Despite of these drawbacks, DNA transfection is considered the standard technique for protein expression. The CTI-financed project Type 3 Technologies (T3T) is developing an innovative technique matching the above mentioned needs and that is further suited for combination with Omics and allows for biochemical experiments. The method, which was first established in the lab of Prof. Cécile Arrieumerlou at the Biozentrum Basel, is based on a bacterial protein delivery nanomachine: the type 3 secretion system (T3SS) encoded by several Gram-negative bacteria. The system delivers bacterial proteins – so-called effectors – directly into eukaryotic host cells. A genetically engineered bacterial strain, which is deprived of all endogenous effectors, serves as the basis for translocating only the proteins of choice into the eukaryotic cells. This system offers distinct advantages: protein delivery is fast, synchronized, homogenous and efficient. Furthermore, our tool can be applied to almost all available cell lines with consistent performance.