Abstract：［Abstract］Objective： By bioinformatical analysis to predict the basic physical and chemical properties, signal peptide and function of hp0521 gene encoding cytotoxinassociated gene 2(Cag2) protein in four Helicobacter pylori strains. Methods：The hp0521 gene sequences in four Hp strains were cloned by PCR and sequenced, and the basic physical and chemical properties, signal peptide as well as protein fingerprint of the encoded Cag2 protein were analyzed by bioinformatics tools. Results：We successfully cloned and sequenced hp0521 gene sequences in four Hp strains and submitted and checked them to GenBank database, and then obtained relevant accession number, KU862627KU062630. The number and molecular weight of hp0521 gene encoding Cag2 protein amino acid were different, but the Cag2 protein was no signal peptide, stable hydrophilic protein with the weak basic theoretical isoelectric point; Cag2 protein contains label of the DNA topoisomerase I, leukocyte interleukin 3 cytokines, antiproliferative protein BTG1 family, mediating cell wall extension protein, halogen acid removal of halogen enzyme/epoxide hydrolase, regulating chromosome condensation function RCC1 family and so on through fingerprint analysis. Conclusion：In the Hp, the hp0521 gene encoding Cag2 protein may mediate cell wall extension and regulate the chromosome condensation, and may be involved in the pathogenic pathway conduction, meanwhile, Cag2 protein itself may have the DNA topoisomerase I and halogen acid removal of halogen enzyme/epoxide hydrolase corresponding enzyme activity, etc.
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2016, Vol. 26 
