奶牛乳房炎金黄色葡萄球菌FnbpB-D基因的表达及其抗血清活性

Expression of fibronectin-binding protein B (FnbpB) region D of Staphylococcus aureus and antiserum activity

纤维素结合蛋白B(FnbpB)是金黄色葡萄球菌(S.aureus)最主要的黏附因子之一,它能够介导S.aureus结合于细胞表面的纤维连结素(Fn)和纤维蛋白原(Fg)。FnbpB基因中D区为主要活性部位。本实验利用pET-32a表达载体表达了S.aureus FnbpB-D重组蛋白(34.7ku),并通过动物实验对重组FnbpB-D蛋白的抗血清活性进行了初步研究。采用ELISA对抗血清进行抗粘附性检测,结果显示实验组与对照组差异极显著(p<0.01),抗血清具有较强的抑制S.aureus黏附纤维连结素的作用。此外,调理吞噬实验结果显示,免疫兔全血对S.aureus有较强的调理作用。这些实验结果将为制备奶牛乳房炎S.aureus黏附素疫苗的研制提供参考。

The fibronectin binding protein B（FnbpB） is one of the most important adhesions involved in the pathogenesis of staphylococcal bovine mastitis.In the present study,the region D of Fnbp B（FnbpB-D） gene of Staphylococcus aureus was cloned into expression vector pET-32a and expressed in E.coli.The expressed recombinant FnbpB-D was 34.7 ku by SDS-PAGE analysis and used to prepare antiserum against FnbpB in rabbit.The inhibition of bacterial adherence and the opsonophagocytic assay showed that the sera against FnbpB were more efficient than normal sera（p0.01）.These results are promising and suggest that the FnbpB-D appears to be an potential target for Saureus infection.