Li Yang, Han Wenyu, Lei Liancheng, Li Zhijie, Shi Lei
College of Animal Science and Veterinary Medicine, Jilin University, Changchun 130062, China.
Wei Sheng Wu Xue Bao. 2009 May;49(5):638-42.
The mrkD gene encodes the adhesin which mediates Klebsiella pneumoniae to adhere human respiratory tissue. We aimed to analyze the adhesion mechanism and adhesion block function of MrkD adhesin.
The recombinant glutathione-S-transferase (GST)-tagged adhesive protein (MrkD) was expressed in E. coli and was purified to homogeneity using GST affinity chromatography. The GST tag was cut by thrombin to obtain the MrkD protein that was identified by SDS-PAGE and Western blot. The adhesive activity of MrkD was examined by adhesive experiments and the binding site was observed by laser confocal microscopy.
The adherent activity of Klebsiella pneumoniae was significantly inhibited by the MrkD. These experimental data demonstrated that the MrkD inhibited the adhesion of Klebsiella pneumoniae.
Our results suggest that MrkD adhesin contains the adhesion epitopes. The future work will be carried out to identify the epitopes and characterize them, then to optimize the combination presentation of these epitopes to develop an efficient vaccine for Klebsiella pneumoniae.
mrkD基因编码介导肺炎克雷伯菌黏附人呼吸道组织的黏附素。我们旨在分析MrkD黏附素的黏附机制及黏附阻断功能。
重组谷胱甘肽-S-转移酶（GST）标记的黏附蛋白（MrkD）在大肠杆菌中表达，并用GST亲和层析法纯化至同质。用凝血酶切割GST标签以获得MrkD蛋白，通过SDS-PAGE和蛋白质印迹法进行鉴定。通过黏附实验检测MrkD的黏附活性，并用激光共聚焦显微镜观察结合位点。
MrkD显著抑制了肺炎克雷伯菌的黏附活性。这些实验数据表明MrkD抑制了肺炎克雷伯菌的黏附。
我们的结果表明MrkD黏附素含有黏附表位。未来将开展工作以鉴定这些表位并对其进行表征，然后优化这些表位的组合呈现方式，以开发一种针对肺炎克雷伯菌的高效疫苗。
