Weapons of Mass Secretion: The Type III Secretion System of Shigella flexneri

In bacteria that are pathogenic for animals, type III secretion systems allow extracellular bacteria adhering to the surface of a host cell to inject specialized proteins across the plasma membrane. The injected proteins subvert the functioning of the aggressed cell or destroy its communications, favoring the entry or survival of the invading bacteria. Type III is thus not a secretion apparatus in the strict sense of the term but rather a complex weapon for close combat that contributes to a number of totally different animal diseases with a variety of symptoms and severities. The body of work in this thesis uses genetics, biochemistry, proteomics and electron microscopy structural analysis to dig deeper into the workings of this apparatus in Shigella flexneri