γ蛋白杆菌
Β-变形菌
嗜酸热硫化叶菌
生物
发起人
DNA
鞭毛
大肠杆菌
α蛋白细菌
基因
响应调节器
遗传学
放线菌门
基因表达
16S核糖体RNA
古细菌
突变体
作者
So Yeon Cho,Han Byeol Oh,Sung‐il Yoon
标识
DOI:10.1016/j.bbrc.2023.06.033
摘要
Bacterial flagella are assembled with ∼30 different proteins in a defined order via diverse regulatory systems. In gram-negative bacteria from the Gammaproteobacteria and Betaproteobacteria classes, the transcription of flagellar genes is strictly controlled by the master regulator FlhDC. In Gammaproteobacteria species, the FlhDC complex has been shown to activate flagellar expression by directly interacting with the promoter region in flagellar genes. To obtain the DNA-binding mechanism of FlhDC and determine the conserved and distinct structural features of Betaproteobacteria and Gammaproteobacteria FlhDCs that are necessary for their functions, we determined the crystal structure of Betaproteobacteria Cupriavidus necator FlhDC (cnFlhDC) and biochemically analyzed its DNA-binding capacity. cnFlhDC specifically recognized the promoter DNA of the class II flagellar genes flgB and flhB. cnFlhDC adopts a ring-like heterohexameric structure (cnFlhD4C2) and harbors two Zn-Cys clusters, as observed for Gammaproteobacteria Escherichia coli FlhDC (ecFlhDC). The cnFlhDC structure exhibits positively charged surfaces across two FlhDC subunits as a putative DNA-binding site. Noticeably, the positive patch of cnFlhDC is continuous, in contrast to the separated patches of ecFlhDC. Moreover, the ternary intersection of cnFlhD4C2 behind the Zn-Cys cluster forms a unique protruding neutral structure, which is replaced with a charged cavity in the ecFlhDC structure.
科研通智能强力驱动
Strongly Powered by AbleSci AI