Lea Group

Home

Structures

People

Techniques

Publications

Links

Positions

Contact us

Gram-negative bacteria commonly interact with animal and plant hosts using type III secretion systems (T3SSs) for translocation of proteins into eukaryotic cells during infection. The T3SS is a complex assembly of 25 protein. It is essential for virulence. It is homologous to the  flagella system. We like to understand its structure, especially structural basis of activation.

The project focuses on understanding the structure of the extracellular part of the secretion apparatus - the secretion needle. The structure has been analysed to 16A on the basis of data obtained by electron microscopy. It reveals a 500A long needle with 70A diameter that is traversed by a central channel of 25A width (see below for more details).

Helical structure of the needle of the type III secretion system of Shigella flexneri.
Cordes et al., J Biol Chem. 2003 May 9;278(19):17103-7