...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemistry >Evidence for breaking domain-domain functional communication in a synthetase-tRNA complex.
【24h】

Evidence for breaking domain-domain functional communication in a synthetase-tRNA complex.

机译：在合成酶-tRNA复合物中破坏域-域功能性交流的证据。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We report here evidence for mutations that break domain-domain functional communication in a synthetase-tRNA complex. Each synthetase is roughly divided into two major domains that are paralleled by the two arms of the L-shaped tRNA structure. The active-site-containing domain interacts with the acceptor arm of the tRNA. The second domain frequently interacts with the anticodon-containing arm. By an induced-fit mechanism, contacts with the anticodon can activate formation of a robust transition state at a site over 70 A away. This induced-fit-based activation is thought to occur through domain-domain signaling and is seen by the enhancement of aminoacylation of the anticodon-containing full tRNA versus a substrate based on the acceptor arm alone. Here we describe a rationally designed mutant methionyl-tRNA synthetase containing two point substitutions at sites that potentially link an anticodon-binding motif to the catalytic domain. The double mutation had no effect on interactions with either the isolated acceptor arm or the anticodon stem-loop. In contrast to interactions with the separate pieces, the mutant enzyme was severely impaired for binding the native tRNA and lost much of its ability to enhance the rate of charging of the full tRNA over that of a substrate based on the acceptor arm alone. We propose that these residues are part of a network for facilitating domain-domain communication for formation of an active synthetase-tRNA complex by induced fit.
机译：我们在这里报告的证据破坏了合成酶-tRNA复合物中的域结构域功能沟通。每个合成酶大致分为两个主要结构域，两个主要结构域与L形tRNA结构的两个臂平行。含活性位点的域与tRNA的受体臂相互作用。第二结构域经常与含反密码子的臂相互作用。通过感应拟合机制，与反密码子的接触可以激活在超过70 A的位点形成稳固的过渡态。这种基于诱导拟合的激活被认为是通过域结构域信号发生的，并且通过相对于仅基于受体臂的底物，含反密码子的完整tRNA的氨酰化作用增强而可见。在这里，我们描述了一个合理设计的突变甲硫氨酰-tRNA合成酶，在可能将反密码子结合基序连接到催化域的位点包含两个点取代。双重突变对与分离的受体臂或反密码子茎环的相互作用没有影响。与与分开的部分的相互作用相反，突变酶与天然tRNA的结合受到严重损害，并且丧失了其增强完整tRNA充电速率的能力超过仅基于受体臂的底物的能力。我们建议这些残基是网络的一部分，以促进通过诱导拟合形成活性合成酶-tRNA复合物的域-域通信。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号