通过19F核磁共振光谱观察到的大肠杆菌精氨酰-tRNA合成酶中底物诱导的构象变化。

Substrate-induced conformational changes in Escherichia coli arginyl-tRNA synthetase observed by 19F NMR spectroscopy.

作者信息

Yao Yong-Neng, Zhang Qing-Shuo, Yan Xian-Zhong, Zhu Guang, Wang En-Duo

机构信息

State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, 320 Yue Yang Road, 200031, Shanghai, PR China.

出版信息

FEBS Lett. 2003 Jul 17;547(1-3):197-200. doi: 10.1016/s0014-5793(03)00717-8.

DOI:10.1016/s0014-5793(03)00717-8

PMID:12860413

Abstract

The 19F nuclear magnetic resonance (NMR) spectra of 4-fluorotryptophan (4-F-Trp)-labeled Escherichia coli arginyl-tRNA synthetase (ArgRS) show that there are distinct conformational changes in the catalytic core and tRNA anticodon stem and loop-binding domain of the enzyme, when arginine and tRNA(Arg) are added to the unliganded enzyme. We have assigned five fluorine resonances of 4-F-Trp residues (162, 172, 228, 349 and 446) in the spectrum of the fluorinated enzyme by site-directed mutagenesis. The local conformational changes of E. coli ArgRS induced by its substrates observed herein by 19F NMR are similar to those of crystalline yeast homologous enzyme.

摘要

4-氟色氨酸（4-F-Trp）标记的大肠杆菌精氨酰-tRNA合成酶（ArgRS）的19F核磁共振（NMR）光谱表明，当向未结合配体的酶中添加精氨酸和tRNA（Arg）时，该酶的催化核心以及tRNA反密码子茎环结合结构域会发生明显的构象变化。我们通过定点诱变确定了氟化酶光谱中4-F-Trp残基（162、172、228、349和446）的五个氟共振峰。本文通过19F NMR观察到的大肠杆菌ArgRS受其底物诱导的局部构象变化与结晶酵母同源酶的构象变化相似。