Published online Jan 21, 2014. doi: 10.3748/wjg.v20.i3.630
Revised: October 30, 2013
Accepted: November 28, 2013
Published online: January 21, 2014
Helicobacter pylori (H. pylori) gamma-glutamyl transpeptidase (GGT) is a bacterial virulence factor that converts glutamine into glutamate and ammonia, and converts glutathione into glutamate and cysteinylglycine. H. pylori GGT causes glutamine and glutathione consumption in the host cells, ammonia production and reactive oxygen species generation. These products induce cell-cycle arrest, apoptosis, and necrosis in gastric epithelial cells. H. pylori GGT may also inhibit apoptosis and induce gastric epithelial cell proliferation through the induction of cyclooxygenase-2, epidermal growth factor-related peptides, inducible nitric oxide synthase and interleukin-8. H. pylori GGT induces immune tolerance through the inhibition of T cell-mediated immunity and dendritic cell differentiation. The effect of GGT on H. pylori colonization and gastric persistence are also discussed.
Core tip: In this review, we focus on the biochemical features and physiological role of Helicobacter pylori (H. pylori) gamma-glutamyl transpeptidase and analyze the mechanisms through which gamma-glutamyl transpeptidase affects H. pylori gastric colonization, persistence, immune tolerance and damage to the gastric mucosa.