金黄色葡萄球菌腺苷酰转移酶耐药基因的克隆及其原核表达

目的在大肠杆菌中克隆表达金黄色葡萄球菌氨基糖苷类耐药基因,即腺苷酰转移酶基因,为其功能研究奠定基础。方法按金黄色葡萄球菌腺苷酰转移酶蛋白编码序列设计引物,以金黄色葡萄球菌基因组DNA为模板,扩增腺苷酰转移酶基因,所得片段与pGEX-4t-1(+)载体连接,转化至感受态大肠杆菌BL21(DE3),提取质粒进行双酶切及测序鉴定,IPTG诱导重组蛋白表达,SDS-PAGE及Western-blot对重组蛋白作鉴定。结果使用金黄色葡萄球菌基因组为模板,成功扩增约800bp目的片段,重组质粒双酶切见目的片段,测序显示腺苷酰转移酶基因长783bp,始于ATG,止于TAG,预测的等电点和相对分子质量分别为7.75和29×103,目的基因与Genbank腺苷酰转移酶同源性为99%,SDS-PAGE及Western-blot显示在55×103见重组蛋白表达。结论在大肠杆菌中成功克隆表达了金黄色葡萄球菌腺苷酰转移酶基因。

Clone and prokaryotic expression of staphylococcus aureus drug resistance adenylyltransferase gene

Objective To clone and express Staphylococcus aureus drug resistance adenylyltransferase gene in E .coli BL21 ,and to make the foundation for its function research .Methods Primers were designed on the basis of adenylyltransferase gene in gen‐bank ,PCR was used to amplify adenylyltransferase gene using Staphylococcus aureus genomic DNA as template .The obtained PCR production was attatched with pGEX‐4t‐1(+ ) plasmid ,and transformed into E .coli BL21 (DE3) .The recombinant plasmid was di‐gested by double enzyme digestion and identified by gene sequence .The recombinant protein was induced to expression by IPTG and identified by Western‐blotting .Results Using Staphylococcus aureus genome as a template ,the target fragment about 800 bp was successful amplified .After enzyme‐cutting and DNA‐sequencing ,the target fragment showed that the ORF begin with ATG ,end with TAG ,783 bp in length ,the predicted isoelectric point and molecular weight were 7 .75 and 29 × 103 ,and it was homology 99%homology with the reported sequence gene in genbank .SDS‐PAGE and Western‐blot showed the molecular weight of recombinant fusion protein was about 55 × 103 .Conclusion Adenylyltransferase gene of Staphylococcus aureus was successfully cloned and ex‐pressed in E .coli as a fusion protein ,which makes the foundation for the research of its function .