ULTRASTRUCTURAL-LOCALIZATION OF UREASE OF HELICOBACTER-PYLORI

Helicobacter pylori urease was characterized by means of an enzyme his tochemical electron microscopic technique. Ultrastructural analysis re vealed no urease activity in one strain; in seven H. pylori strains (4 3.75 %), urease activity was associated with the cell membrane. Eight strains (50.0 %) showed reaction product located within the cytoplasm. Urease activity showed no correlation with localization of activity. Our results demonstrate that H. pylori urease is not uniform in all H. pylori strains, and differences in activity and localization of ureas e activity may account for different virulence activities.