链球菌蛋白G的构建、重组表达及鉴定  

Construction,expression and identification of a recombinant streptococcal protein G

作　　者：安明岩[1,2] 褚仲梅[3] 张毅[3,2] 

机构地区：[1]华东理工大学生物工程学院,上海200237 [2]中科院合成生物学重点实验室,上海200032 [3]中科院上海生命科学研究院,上海200233

出　　处：《工业微生物》2012年第2期1-5,共5页Industrial Microbiology

基　　金：国家"973项目"(2007CB714304)

摘　　要：化学合成链球菌蛋白G的C3D基因片段,通过分子生物学的方法对蛋白G(proteinG)的C3片段进行PCR扩增,拼接形成含有两个和三个重复C3片段的重组链球菌蛋白G,C3片段间以链接区D连接,即形成C3DC3和C3DC3DC3的形式,进而克隆到质粒pET21中,在大肠杆菌BL21(DE3)中表达。重组表达的蛋白经过DEAE-Sepharose和IgG-Sepharose纯化,得到纯化的重组蛋白。采用非竞争性酶免疫法对重组蛋白与不同来源IgG的结合常数进行测定,实验结果显示两种重组链球菌蛋白G均可有效地与小鼠、兔及山羊等多种不同来源抗体特异性结合。这些实验结果为下一步研究奠定了基础。In this study, the gene fragment encoding the streptococcal protein G （23 domain was chemically synthesized. Two kinds of protein G genes （protein G1, with two repeats of C3 and protein G2, with three repeats of C3） were constructed. The native streptococcal protein G linker D domain were also synthesized and inserted between the C3 domain repeats. Protein G1 or protein G2 genes was cloned into plasmid pET21, and subsequently transformed into E. coli BL21 （DE3）. The recombinant proteins, namely protein G1 and protein G2, were purified by DEAE-Sepharose and IgG-Sepharose. Finally, the affinity constants between recombinant proteins and different sources of IgGs were determined by non-competitive enzyme immunoassay method. The result showed that both protein G1 and G2 could specifically bind with different IgGs while protein G2 had higher binding affinity than protein G1.

关 键 词：重组 PROTEIN G 纯化 亲和常数 

分 类 号：Q936[生物学—微生物学]