Genetic diagnosis of H. pylori strains
Azuma, T.
Nihon Rinsho. Japanese Journal of Clinical Medicine 59(2): 286-290
2001
ISSN/ISBN: 0047-1852 PMID: 11218399 Document Number: 534498
Helicobacter pylori strains are divided into two broad families, type I and type II, based on whether or not they possess the cag pathogenicity island (cagPAI). It has been suggested that cagPAI is inherited by horizontal transfer from an unknown microorganism, and the genes of cag are thought to be encoded by a putative type IV secretory system. In addition, CagA may be delivered from attached H. pylori into the host crytoplasm by this system and is tyrosine phosphorylated in gastric epithelial cells. The phosphorylated CagA may play a crucial role in promoting the inflammatory responses of gastric mucosa. These findings suggest that type I H. pylori is a pathogenic H. pylori.