布鲁氏菌外膜蛋白D15的表达及生物学活性分析

Cloning and biological characterization of the surface antigen D15 of Brucella abortus

为研究布鲁氏菌D15蛋白的生物学特性,本实验通过PCR技术扩增牛型布鲁氏菌外膜蛋白基因D15,并克隆至表达载体pCold TF中,构建重组表达质粒pCold-D15,原核表达了约为130 ku的His标记重组蛋白His-D15。Western blot结果显示:D15能够与布鲁氏菌阳性牛血清发生特异性反应;并且具有纤连蛋白溶酶原结合活性,但不具有纤连蛋白结合活性。本研究为进一步研究D15蛋白在牛型布鲁氏菌感染、检测及亚单位疫苗的研制等方面的作用奠定基础。

The D15 protein is a surface antigen of Brncella abortus, which is up-regulated expression in infected animals. In order to investigate its function, the DI5 gene of B.abortus A19 was amplified by PCR and cloned into the expression vector pColdTF for expression in E.coli BL21 （DE3）. The recombinant D15 protein （rD15） was expressed with the induction of IPTG. Then, the immunogenicity, binding activities between fibronectin and plasrninogen of the rD15 were determined by using the western blot. The results showed that rD15 was able to specifically react with the Brucella positive serum fi＇orn cattle, and had the plasrninogen-binding activity but not fibronectin-binding antivity. The results of this study provided the basis for further study of the roles of D15 in the B.abortus infection.