中文摘要：

目的分析表皮葡萄球菌SrrAB生物信息,表达及纯化SrrA蛋白,为SrrA功能研究奠定基础。方法以表皮葡萄球菌SE1457基因组为模板,PCR扩增srrA基因,构建重组表达质粒pET28a-srrA,转入大肠杆菌BL21,利用纯化的重组蛋白SrrA免疫小鼠,制备SrrA多克隆抗体,并检测SrrA在表皮葡萄球菌不同生长时期的表达水平。序列比对利用Clustalw2软件,蛋白结构域分析用DNAMAN软件。结果表皮葡萄球菌SE1457SrrAB单独组成一个操作子,SrrA位于胞浆中,与金黄色葡萄球菌和枯草杆菌类似物的同源性分别为95%和65%,SrrB为跨膜蛋白,与上述细菌类似物的同源性分别为71%和33%;表皮葡萄球菌SrrA于对数生长中期表达量最高。结论成功表达并纯化了表皮葡萄球菌SrrA蛋白,为SrrAB下游调控机制研究奠定基础。

英文摘要：

We analyzed the bioinformatics of SrrAB and the response regulator protein SrrA in Staphylococcus epidermidis.The PCR fragment of srrAfrom the genome of SE1457 was digested with EcoRI and XhoI endonucleases,and inserted into plasmid pET28 a.The recombinant plasmid pET28a-srrA was transferred into E.coli BL21.Purified recombinant protein HisSrrA was injected into Balb/c mouse for the production of anti-SrrA polyclonal antibodies,and then to detect the expression level of SrrA in the different phase of grow curve.Clustalw2 software was used for multiple sequence alignment,and DNAMAN for domain analysis.Results showed that the srrABgenes formed a separate operon in SE1457.Respectively,SrrA protein,sharing 95% and 65% sequence identity with that of S.aureus and B.subtilis,located in the cytoplasm;SrrB,sharing71%and 33%sequence identity with that of S.aureus and B.subtilis,anchored on the cell membrane.Expression level of SrrA was highest in the middle of the logarithmic phase.It facilitated the research on the mechanism of SrrA protein when it has been expressed and purified in this work.