Protein Secretion and Pathogenesis in Helicobacter pylori
Robin M. Delahay and Darren P. Letley
from: Bacterial Secreted Proteins: Secretory Mechanisms and Role in Pathogenesis (Edited by: Karl Wooldridge). Caister Academic Press, U.K. (2009)
Helicobacter pylori establishes a persistent colonisation of the human stomach which results in a chronic active gastritis. Approximately half the world population is infected with this bacterium, although the majority of infections are asymptomatic. However, persistent H. pylori colonisation can lead to severe pathological outcomes, such as peptic ulcer disease and gastric adenocarcinoma, in a manner dependent upon host, environmental and bacterial factors. The two most extensively studied H. pylori virulence factors are secreted products; the vacuolating cytotoxin, VacA, and CagA, an effector protein delivered by the cytotoxin-associated gene (cag) type IV secretion system. In addition to these major virulence determinants, H. pylori releases many other proteins into its environment which contribute to the colonisation and pathogenesis of this organism. This chapter describes the known pathogenic role of some of these secreted factors with particular emphasis on VacA, CagA and the type IV secretion system encoded by the cag pathogenicity island read more ...