当前位置: X-MOL 学术bioRxiv. Biochem. › 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.)
Decoding the Mechanism of Specific RNA Targeting by Ribosomal Methytransferases
bioRxiv - Biochemistry Pub Date : 2021-09-15 , DOI: 10.1101/2021.09.15.460497
Juhi Singh , Rahul Raina , Kutti R Vinothkumar , Ruchi Anand

Methylation of specific nucleotides is integral for ribosomal biogenesis and serves as a common way to confer antibiotic resistance by pathogenic bacteria. Here, by determining the high-resolution structure of 30S-KsgA by cryo-EM, a state was captured, where KsgA juxtaposes between helices h44 and h45, separating them, thereby enabling remodeling of the surrounded rRNA and allowing the cognate site to enter the methylation pocket. With the structure as a guide, factors that direct the enzyme to its cognate site with high fidelity were unearthed by creating several mutant versions of the ribosomes, where interacting bases in the catalytic helix h45 and surrounding helices h44, h24, and h27 were mutated and evaluated for their methylation efficiency. The biochemical studies delineated specificity hotspots that enable KsgA to achieve an induced fit. This study enables the identification of distal exclusive allosteric pocket and other divergent structural elements in each rMTase, which can be exploited to develop strategies to reverse methylation, mediated drug resistance.

中文翻译:

核糖体甲基转移酶对特定 RNA 靶向机制的解码

特定核苷酸的甲基化是核糖体生物发生不可或缺的一部分,并且是致病细菌赋予抗生素抗性的常见方式。在这里,通过冷冻电镜确定 30S-KsgA 的高分辨率结构,捕获了一种状态,其中 KsgA 并列在螺旋 h44 和 h45 之间,将它们分开,从而能够重塑被包围的 rRNA 并允许同源位点进入甲基化口袋。以结构为指导,通过创建核糖体的几个突变版本,发现了将酶以高保真度引导至其同源位点的因素,其中催化螺旋 h45 和周围螺旋 h44、h24 和 h27 中的相互作用碱基发生突变,评估它们的甲基化效率。生化研究描绘了使 KsgA 能够实现诱导拟合的特异性热点。
更新日期:2021-09-17
down
wechat
bug