CagZ is a 23 kDa protein consisting of a single compact L-shaped domain, composed of seven alpha-helices that run antiparallel to each other. 70% of the residues are in alpha-helix conformation and no beta-sheet is present. CagZ is essential for the translocation of the pathogenic protein CagA into host cells [1].

1: Crystal structure of CagZ, a protein from the Helicobacter pylori pathogenicity island that encodes for a type IV secretion system. Cendron L, Seydel A, Angelini A, Battistutta R, Zanotti G; J Mol Biol. 2004;340:881-889. PMID:15223328