Crystal structure of the choline-binding protein CbpJ from Streptococcus pneumoniae
Crystal structure of the choline-binding protein CbpJ from Streptococcus pneumoniae
复制标题
肺炎链球菌胆碱结合蛋白 CbpJ 的晶体结构
DOI：
10.1016/j.bbrc.2019.05.053
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发表时间：
2019
影响因子：
3.1
通讯作者：
Jiang Yong-Liang
中科院分区：
文献类型：
--
作者：
Xu Qian;Zhang Jun-Wei;Chen Yuxing;Li Qiong;Jiang Yong-Liang
胆碱结合蛋白在肺炎球菌的定植和毒力中起重要作用。肺炎链球菌TIGR 4的胆碱结合蛋白J（CbpJ）参与了嗜中性粒细胞在宿主体内的定植，并参与了嗜中性粒细胞的逃避杀伤。在这里，我们报告的2.0晶体结构的CbpJ与胆碱的复合物。CbpJ由N-末端推定功能结构域（N-结构域）和C-末端胆碱结合结构域（CBD）组成。N结构域含有四个退化的胆碱结合重复序列（CBR），这些重复序列失去了与胆碱结合的能力，而CBD则由七个典型的CBR组成。进一步的功能测定表明，CBD有助于肺炎球菌粘附到人肺上皮细胞A549。这些发现提供了深入了解肺炎球菌的发病机制，并扩大了我们对胆碱结合蛋白的功能的理解。
The choline-binding proteins play essential roles in pneumococcal colonization and virulence. It has been suggested that the choline-binding protein J (termed CbpJ; encoded by the genesp_0378) fromStreptococcus pneumoniaeTIGR4 involves in the colonization in host and contributes to evasion of neutrophil killing. Here we report the 2.0 Å crystal structure of CbpJ in complex with choline. CbpJ consists of an N-terminal putative functional domain (N-domain) followed by a C-terminal choline-binding domain (CBD). The N-domain harbors four degenerated choline-binding repeats (CBRs) that lose the capacity of binding to choline, whereas the CBD is composed of seven typical CBRs. Further functional assays showed that the CBD contributes to the pneumococcal adhesion to human lung epithelial cell A549. These findings provide insights into the pneumococcal pathogenesis and broaden our understanding on the functions of choline-binding proteins.