Identification And Functional Analysis Of Related Proteins Of Helicobacter Pylori Coccoid Variation Under Oxidative Stress

Helicobacter pylori(H.pylori) is the major cause of chronic gastritis and plays an important role in the pathogenesis of peptic ulcer and gastric adenocarcinoma. However, the bionomics and pathogenesis mechanisms of H.pylori remains unclear. H.pylori exists a high level of biological diversity compared with other bacteria. On the condition of complicate survivable environment, it possesses high variability and distinct adaptive mechanisms. H.pylori is prone to convert to coccoid form from spiral form when exposed to adverse conditions, such as under oxidative stress. Finally H.pylori transforms into coccoid variant which is viable but noculturable stage. The coccoid forms may play an important role in transmission route of H.pylori and the recrudescence of gastritis. Research on the variant character and variant essence of H.pylori under oxidative stress will be helpful to clarify adaptive variant mechanisms and potential transmission route of H.pylori, as well as providing potent experimental basis for the study on culture of tolerance to oxygen to reforming H.pylori through genetic engineering technique.On the basis of these consideration, we deployed the culture condition of high oxygen pressure to establish stable H.pylori coccoid form model under oxidative stress. The investigations of the ultrastructure, the activities of metalbolism and enzyme, the real-time RT-PCR detections of H.pylori virulence factors and the possible recovery in vitro and in vivo were carried out. Meanwhile, two-dimensional electrophoresis (2-DE) were employed to compare the differential expression proteins between the spiral form and coccoid form of H.pylori. The differential proteins were identified by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). Eventually, we constructed the H.pylori recombinant strain of high expressing differential protein, and verified its effects to H.pylori's tolerance to oxygen under oxidative stress. Main results are listed below:...