［摘要］目的: 对4株幽门螺杆菌(Helicobacter pylori, Hp)中hp0521基因编码的细胞毒素相关基因2(cytotoxinassociated gene 2，Cag2)蛋白从生物信息学角度进行基本理化性质、信号肽及功能的预测分析。方法: 用PCR技术克隆测序获得4株Hp菌株的hp0521基因序列，生物信息学工具分析其编码Cag2蛋白的基本理化性质、有无信号肽及蛋白指纹图谱。 结果： 成功克隆测序4株Hp菌株的hp0521基因序列，提交基因库后获得相应登录号；hp0521基因编码的Cag2蛋白氨基酸数目和相对分子质量大小不同，理论等电点偏碱性，为稳定亲水性蛋白，不存在信号肽；Cag2蛋白指纹图谱分析存在DNA拓扑异构酶Ⅰ、IL3细胞因子、抗增殖蛋白BTG1家族、介导细胞壁延伸的蛋白、卤酸脱卤酶/环氧水解酶、调节染色体凝集功能RCC1家族等蛋白标签。结论： Hp中hp0521基因编码的Cag2蛋白可能介导细胞壁延伸和调节染色体凝集，参与致病信号通路的传导，可能具有DNA拓扑异构酶Ⅰ、卤酸脱卤酶/环氧水解酶等相应酶活性。
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.
关键词
幽门螺杆菌 /
cag致病岛 /
hp0521 /
生物信息学
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参考文献
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脚注
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基金
国家自然科学基金资助项目(81271795);高等学校博士学科点专项科研基金(博导类)资助项目(20123227110008)
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