Structural and Functional Characterization of the Helicobacter pylori protein CagA

Helicobacter pylori is a pathogenic bacteria which infects the gastric epithelium and induces adenocarcinoma. CagA is a major virulence factor of H. pylori, which is translocated into the cytosol of gastric epithelium, mainly by the aid of type IV secretion system. The main objectives of this thesis are the structural and functional analysis of CagA middle fragments using methods such as crystallization and X-ray diffraction, circular dichroism, multi-angle light scattering, and microscopy techniques. Results showed that CagA middle domain is folded and monomeric. It induces the development of a novel macrospike phenotype and triggers its uptake into the gastric epithelium.