Zhang Chunmao, Hao Huaijie, Yu You, Kong Decong, Chen Shaolong, Jiang Hua, Yuan Yuan, Zheng Yuling, Yang Maojun, Jiang Yongqiang
State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, China.
Key Laboratory for Protein Sciences of Ministry of Education, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.
FEBS Lett. 2016 May;590(9):1384-92. doi: 10.1002/1873-3468.12174. Epub 2016 May 5.
The recently identified Streptococcus suis adhesin factor H-binding protein (Fhb) targets the host cellular receptor glycolipid GbO3 through its N terminus. However, it is unclear how Fhb interacts with its receptor. Here, we determined the complex structure of factor H-binding protein receptor-binding domain (Fhb RBD) with Gb2, an analog of its receptor, revealing that Gb2 binds in a pocket of the β sandwich core domain. We identified the key residues for Fhb RBD receptor binding using mutagenesis and isothermal titration calorimetry. Mutagenesis analyses indicated that Fhb binds to Gb2 mainly through hydrogen and hydrophobic interactions. Our findings provided structural insights into the Fhb-mediated host-pathogen interactions of S. suis.
最近鉴定出的猪链球菌粘附因子H结合蛋白（Fhb）通过其N端靶向宿主细胞受体糖脂GbO3。然而，尚不清楚Fhb如何与其受体相互作用。在此，我们确定了因子H结合蛋白受体结合结构域（Fhb RBD）与Gb2（其受体类似物）的复合物结构，揭示Gb2结合在β三明治核心结构域的一个口袋中。我们使用诱变和等温滴定量热法确定了Fhb RBD受体结合的关键残基。诱变分析表明，Fhb主要通过氢键和疏水相互作用与Gb2结合。我们的研究结果为猪链球菌Fhb介导的宿主-病原体相互作用提供了结构上的见解。
