Release Factors 2 from Escherichia coli and Thermus thermophilus: structural, spectroscopic and microcalorimetric studies
Release Factors 2 from Escherichia coli and Thermus thermophilus: structural, spectroscopic and microcalorimetric studies
复制标题
大肠杆菌和嗜热栖热菌释放因子 2：结构、光谱和微量热研究
作者：
Gabriel Zoldá;L. Redecke;D. Svergun;P. Konarev;Stefan Voertler;H. Dobbek;Erik Sedlá;M. Sprinzl
脯氨酸I类释放因子（RF）响应mRNA终止密码子并终止蛋白质合成。它们与核糖体解码位点和肽基转移酶中心相互作用，桥接这75个相距遥远的核糖体中心。为此，需要具有部分未折叠的核心域II·III·IV的细长RF构象，这与已知的紧凑RF晶体结构形成对比。测定了Thermus thermophilus RF 2的晶体结构，并与T.通过微量热法、圆二色谱法和小角X射线散射法对嗜热菌和大肠杆菌RF2进行了鉴定。T.嗜热菌RF2在20°C下的溶液中主要是像晶体结构一样紧凑的。热力学分析指出，域I的初始熔化，这是独立于熔化的核心。核心结构域II·III·IV在T. thermophilus和E.杆菌热力学分析和X射线散射结果表明，T。嗜热菌RF2在溶液中的构象表明RF2的紧凑构象类似于不存在核糖体的生理状态。
Prokaryotic class I release factors (RFs) respond to mRNA stop codons and terminate protein synthesis. They interact with the ribosomal decoding site and the peptidyl-transferase centre bridging these 75 Å distant ribosomal centres. For this an elongated RF conformation, with partially unfolded core domains II·III·IV is required, which contrasts the known compact RF crystal structures. The crystal structure of Thermus thermophilus RF2 was determined and compared with solution structure of T. thermophilus and Escherichia coli RF2 by microcalorimetry, circular dichroism spectroscopy and small angle X-ray scattering. The structure of T. thermophilus RF2 in solution at 20°C is predominantly compact like the crystal structure. Thermodynamic analysis point to an initial melting of domain I, which is independent from the melting of the core. The core domains II·III·IV melt cooperatively at the respective physiological temperatures for T. thermophilus and E. coli. Thermodynamic analyses and the X-ray scattering results for T. thermophilus RF2 in solution suggest that the compact conformation of RF2 resembles a physiological state in absence of the ribosome.
影响因子：
--
作者：
Ernesto Freire
通讯作者：
Ernesto Freire
影响因子：
2.9
作者：
MANAVALAN, P;JOHNSON, WC
通讯作者：
JOHNSON, WC
DOI：
10.1093/protein/13.3.179
发表时间：
2000-03-01
期刊：
PROTEIN ENGINEERING
影响因子：
--
作者：
Kumar, S;Tsai, CJ;Nussinov, R
通讯作者：
Nussinov, R