[Prokaryotic expression and preliminary identification of protein CrdS of Helicobacter pylori]

The CrdS protein responding to the acidic adaptation was prokaryotic-expressed in our Laboratory to explore the regulatory mechanism in the acidic adaptation of Helicobacter pylori (H. pylori). The whole genomic DNA of H. pylori strain 26695 was abstracted and set as the template firstly. And then the hp1364 gene coding CrdS protein was amplified via the PCR technique. Then the clonal recombinant plasmid pUCm-T-hp1364 and the prokaryotic expression plasmid pQE30-hp1364 were built and identified by the methods of PCR, cutting with two enzymes and sequencing. After that, the plasmid pQE30-hp1364 was transferred into the E. coli XL1 blue and induced with IPTG. Using western blot and SDS-PAGE, it can be analyzed that the expressed recombinant protein existed mainly in the form of the inclusion bodies and its relative molecular mass was about 46 kDa. The successfully attained recombinant protein CrdS will provide the material to explore the regulatory mechanism in the acidic adaptation of H. pylori and the new way to resist the infection of H. pylori.