National Contagious Bovine Pleuropneumonia Reference Laboratory, Division of Bacterial Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, CAAS, Harbin, China.
PLoS One. 2012;7(6):e38836. doi: 10.1371/journal.pone.0038836. Epub 2012 Jun 13.
Mycoplasma bovis is the causative agent of Mycoplasma bovis-associated disease (MbAD). Although the mechanisms underlying M. bovis adherence to host cells is not clear, recent studies have shown that the cell surface protein α-enolase facilitates bacterial invasion and dissemination in the infected host. In this study, we cloned, expressed and purified recombinant M. bovis α-enolase and induced polyclonal anti-α-enolase antibodies in rabbits. M. bovis α-enolase was detected in the cytoplasmic and membrane protein fractions by these antibodies. Triple immunofluorescence labeling combined with confocal laser scanning microscopy (CLSM) revealed that the plasminogen (Plg) enhanced the adherence of M. bovis to embryonic bovine lung (EBL) cells; the values obtained for adherence and inhibition are consistent with this finding. Interestingly, we found that trace amounts of trypsin acted as a more effective enhancer of cell adherence than Plg. Hence, our data indicate that surface-associated M. bovis α-enolase is an adhesion-related factor of M. bovis that contributes to adherence by binding Plg.
牛支原体是牛支原体相关疾病（MbAD）的病原体。虽然牛支原体黏附宿主细胞的机制尚不清楚，但最近的研究表明，细胞表面蛋白α-烯醇酶促进了感染宿主中的细菌入侵和传播。在这项研究中，我们克隆、表达和纯化了重组牛支原体α-烯醇酶，并在兔子中诱导了多克隆抗α-烯醇酶抗体。这些抗体检测到牛支原体α-烯醇酶存在于细胞质和膜蛋白部分。三重免疫荧光标记结合共聚焦激光扫描显微镜（CLSM）显示，纤溶酶原（Plg）增强了牛支原体对牛胚肺（EBL）细胞的黏附；黏附和抑制的测定值与这一发现一致。有趣的是，我们发现痕量的胰蛋白酶比 Plg 更有效地增强细胞黏附。因此，我们的数据表明，表面相关的牛支原体α-烯醇酶是牛支原体的一种黏附相关因子，通过与 Plg 结合促进黏附。
