2型猪链球菌细胞壁蛋白SSU1664的表达、纯化及活性分析

Expression,purification and activity assay of Streptococcus suis serotype 2 cell wall protein SSU1664

目的:从猪链球菌05ZY中扩增SSU1664基因,在大肠杆菌中表达并评价其重组蛋白的活性。方法:根据05ZY基因组序列设计引物,PCR扩增SSU1664基因,构建表达载体,利用亲和层析对目的蛋白进行纯化,Western blot和ELISA法鉴定其免疫原性。结果:SSU1664基因能够在大肠杆菌中可溶性表达,Western blot显示其能与猪链球菌菌体免疫后的大鼠血清反应,ELISA检测显示在人感染猪链球菌患者血清中针对SSU1664蛋白的IgM含量显著性升高。结论:SSU1664蛋白具有较高的免疫原性,可作为潜在的猪链球菌疫苗候选分子和猪链球菌早期感染诊断的标志物。

AIM：To amplify the SSU1664 gene from Streptococcus suis serotype 2 strain 05ZY,to express the gene in E.coli,and to evaluate the activities of the recombinant protein.METHODS：SSU1664 gene was amplified by PCR using primers according to 05ZY genome sequences and cloned into the expression vector.The recombinant protein was purified by affinity chromatography and its immunogen activities were tested by Western blot and ELISA.RESULTS：SSU1664 gene could solublely express in E.coli BL21（DE3）.Western blot analysis showed that the recombinant protein could react with rat serum immunized with Streptococcus suis,but not with non-immunized rat serum.ELISA assay showed that anti-SSU1664 IgM content in Streptococcus suis-infected patient was significantly higher than that in healthy donors.CONCLUSION：The recombinant SSU1664 protein has immunogen activity and might be one promising Streptococcus suis vaccine candidate and diagnosis marker of Streptococcus suis early infection.