Harpins are proteins able to elicit hypersensitive response (HR) in non-host plants and are required for pathogenicity in host plants. HrpZ forms ion-conducting pores permeable for cations. Such pore-forming activity may allow nutrient release and/or delivery of virulence factors during bacterial colonization of host plants (By similarity). Homomultimeric. Secreted via type III secretion system (TTSS), delivered into the host intercellular space. HrpZ travels through the hrp pilus and it is secreted only from the pilus tip. The glycine-rich region is characteristic of harpins. Belongs to the harpin HrpZ family.