Abstract:To study adaptive protein variation of H. pylori after colonization in Mongolian gerbils, Firstly, Clinical isolated strain M0 of H. pylori were inoculated into Mongolian gerbils and acclimated through serial passages in vivo for procuring an adaptive colonization H. pylori strain. Then, two-dimensional electrophoresis (2-DE) and mass spectrometry(MS) was taken to separate and identify the global proteins significantly changed between H. pylori strain M0and the adaptive strain. Through serial passages the infectious rate increased from about 2/10 to 9/10 and a adaptive colonization strain M13 has been abtained. Comparative proteomic technology display that the proteinogram of H. pylori have changed after colonization in gerbils. Out of 5 differential protein spots cut out of gels for MALDI-TOF-MS identification, 4 spots were successfully identified, among which, Icd, RfaD and HP0318 were significantly higher in M13 compared with M0, while only HypB were found in M13. So far, HP0318 is a conserved hypothetical protein. These proteins may be important factors of H. pylori for adaptive colonization.