当前位置: X-MOL 学术Nucleic Acids Res. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Mechanism of activation of contact-dependent growth inhibition tRNase toxin by the amino acid biogenesis factor CysK in the bacterial competition system
Nucleic Acids Research ( IF 16.6 ) Pub Date : 2024-09-04 , DOI: 10.1093/nar/gkae735
Zhaohang Feng 1 , Yuka Yashiro 1 , Kozo Tomita 1
Affiliation  

Contact-dependent growth inhibition (CDI) is a bacterial competition mechanism, wherein the C-terminal toxin domain of CdiA protein (CdiA-CT) is transferred from one bacterium to another, impeding the growth of the toxin recipient. In uropathogenic Escherichia coli 536, CdiA-CT (CdiA-CTEC536) is a tRNA anticodon endonuclease that requires a cysteine biogenesis factor, CysK, for its activity. However, the mechanism underlying tRNA recognition and cleavage by CdiA-CTEC536 remains unresolved. Here, we present the cryo-EM structure of the CysK:CdiA-CTEC536:tRNA ternary complex. The interaction between CdiA-CTEC536 and CysK stabilizes the CdiA-CTEC536 structure and facilitates tRNA binding and the formation of the CdiA-CTEC536 catalytic core structure. The bottom-half of the tRNA interacts exclusively with CdiA-CTEC536 and the α-helices of CdiA-CTEC536 engage with the minor and major grooves of the bottom-half of tRNA, positioning the tRNA anticodon loop at the CdiA-CTEC536 catalytic site for tRNA cleavage. Thus, CysK serves as a platform facilitating the recognition and cleavage of substrate tRNAs by CdiA-CTEC536.

中文翻译:


细菌竞争系统中氨基酸生物发生因子 CysK 激活接触依赖性生长抑制 tRNase 毒素的机制



接触依赖性生长抑制 (CDI) 是一种细菌竞争机制,其中 CdiA 蛋白 (CdiA-CT) 的 C 端毒素结构域从一种细菌转移到另一种细菌,阻碍毒素受体的生长。在尿路致病性大肠埃希菌 536 中,CdiA-CT (CdiA-CTEC536) 是一种 tRNA 抗密码子核酸内切酶,其活性需要半胱氨酸生物发生因子 CysK。然而,CdiA-CTEC536 识别和切割 tRNA 的机制仍未解决。在这里,我们介绍了 CysK:CdiA-CTEC536:tRNA 三元复合物的冷冻电镜结构。CdiA-CTEC536 和 CysK 之间的相互作用稳定了 CdiA-CTEC536 结构,并促进了 tRNA 结合和 CdiA-CTEC536 催化核心结构的形成。tRNA 的下半部分仅与 CdiA-CTEC536 相互作用,CdiA-CTEC536 的 α 螺旋与 tRNA 下半部分的小沟和大沟结合,将 tRNA 反密码子环定位在 CdiA-CTEC536 催化位点以进行 tRNA 切割。因此,CysK 作为促进 CdiA-CTEC536 识别和切割底物 tRNA 的平台。
更新日期:2024-09-04
down
wechat
bug