Bacterial Nanomachine Serves as a Versatile Tool

Without proteins life would be unthinkable. They fulfill a diverse range of tasks and are often highly specialized. Proteins reproduce genetic material, transport substances and play an active role in the immune defense. In order to understand these pathways and processes of life in more detail, scientists rely on methods enabling the delivery of individual proteins into target cells. In collaboration with researchers at the Biozentrum, the team of Dr. Simon Ittig from the startup “T3 Pharmaceuticals” (T3P) has developed a simple and powerful tool that allows the injection of a wide range of proteins into eukaryotic cells by using bacteria.

Novel technology for protein delivery

For some time now, there have been some methods available to produce proteins of choice in cells. They are mostly based on the introduction of genes into the cell, which then produce the corresponding proteins. These techniques, however, are afflicted with many disadvantages. It is rare that all the cells of a population are affected and the amount and localization of the proteins within the cell often fail to reflect physiological conditions. Based on their valuable experience and building on existing resources, the T3P team has now developed a completely new approach. They employ a bacterial nanomachine, the type 3 secretion system, to deliver the desired proteins into the target cells.

Compared to conventional methods, this novel technology has several advantages. It is extremely powerful and efficient, as the protein is delivered within a minute and multiple proteins can be translocated simultaneously. In addition, the technique is easy to use even for non-specialists and simple to reproduce. The T3P team has substantiated this with numerous experiments. “We were able to successfully inject bacterial, viral and eukaryotic proteins of various sizes into a wide range of different cell types”, says Simon Ittig. “The fusion with localization signals or small antibodies enabled us to also specify their destination within the cell and, furthermore, to investigate programmed cell death and the effects on other proteins within living cells.”