Essential role of urease in pathogenesis of gastritis induced by Helicobacter pylori in gnotobiotic piglets

摘要: A mutant strain of Helicobacter pylori with weak urease activity was created by using N-methyl-N9-nitro-N-nitrosoguanidine. The the (0.036 +/- 0.009 nmol urea per micrograms bacterial protein min) 0.4% that parental (8.20 2.30 min). otherwise indistinguishable from strain. Both demonstrated prominent catalase and oxidase activities, both produced vacuolating cytotoxin. Restriction endonuclease sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) patterns ultrastructure were identical for two strains. fully motile, as evaluated spreading in soft agar direct microscopic examination. Growth rate colony size morphology Seventeen gnotobiotic piglets challenged either or sacrificed 3 21 days after challenge. Gastric tissue examined histologically cultured H. pylori. Of seven strain, all became infected. not recovered any 10 urease-negative Lymphofollicular gastritis present but none These results suggest is essential colonization Images