...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemistry >Switching the amino acid specificity of an aminoacyl-tRNA synthetase
【24h】

Switching the amino acid specificity of an aminoacyl-tRNA synthetase

机译：转换氨酰基-tRNA合成酶的氨基酸特异性

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

The accuracy of protein synthesis essentially rests on aminoacyl-tRNA synthetases that ensure the correct attachment of an amino acid to the cognate tRNA molecule. The selection of the amino acid substrate involves a recognition stage generally followed by a proofreading reaction. Therefore, to change the amino acid specificity of a synthetase in the aminoacylation reaction, it is necessary to alleviate the molecular barriers which contribute its editing function. In an attempt to accommodate a noncognate amino acid into the active site of a synthetase, we chose a pair of closely related enzymes. The current hypothesis designates glutaminyl-tRNA synthetase (GlnRS) as a late component of the protein synthesis machinery, emerging in the eukaryotic lineage by duplication of the gene for glutamyl-tRNA synthetase (GluRS). By introducing GluRS-specific features into the Rossmann dinucleotide-binding domain of human GlnRS, we constructed a mutant GlnRS which preferentially aminoacylates tRNA with glutamate instead of glutamine. Our data suggest that not only the transition state for aminoacyl-AMP formation but also the proofreading site of GlnRS are affected by that mutation. [References: 20]
机译：蛋白质合成的准确性基本上取决于氨酰基-tRNA合成酶，该酶可确保氨基酸正确连接至同源tRNA分子。氨基酸底物的选择通常涉及识别阶段，然后进行校对反应。因此，为了在氨酰化反应中改变合成酶的氨基酸特异性，必须减轻贡献其编辑功能的分子屏障。为了将非同源氨基酸容纳到合成酶的活性位点中，我们选择了一对密切相关的酶。当前的假设将谷氨酰胺-tRNA合成酶（GlnRS）指定为蛋白质合成机制的后期组分，通过重复谷氨酰-tRNA合成酶（GluRS）的基因而出现在真核谱系中。通过将GluRS特定功能引入人GlnRS的Rossmann二核苷酸结合域，我们构建了一个突变GlnRS，该突变体优先用谷氨酸而不是谷氨酰胺对tRNA进行氨酰化。我们的数据表明，不仅氨基酰-AMP形成的过渡状态而且GlnRS的校对位点都受到该突变的影响。 [参考：20]

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