合理设计以阻止tRNA合成酶的氨基酸编辑
Richard S Mursinna1, Susan A Martinis
1Department of Biology and Biochemistry, University of Houston, Houston, Texas 77204-5001, USA.
Journal of the American Chemical Society
|June 20, 2002
概括
研究人员设计了leucyl-tRNA合成酶以防止非标准氨基酸的去除. 这一突破使得在化学生物学中用于定制蛋白质合成的错误充电tRNA的稳定生产成为可能.
科学领域:
- 化学生物学 化学生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 蛋白质合成通常使用20种标准氨基酸.
- 结合新型氨基酸需要专门的工具,如错基化tRNAs.
- 氨基酸-tRNA合成酶确保了准确性,但阻碍了非标准的氨基酸结合.
研究的目的:
- 用非标准氨基酸设计氨基酸-tRNA合成酶,以实现稳定的异样化.
- 为了克服合成酶的编辑活动,去除不正确的氨基酸.
- 用新型氨基酸构建块促进定制蛋白质合成.
主要方法:
- 基-tRNA合成酶的编辑活性位点的理性突变发生.
- 取代大型氨基酸以阻断水解活性.
- 测试工程酶,以稳定地将异黄素与tRNALeu的异化.
主要成果:
- 成功地阻止了leucyl-tRNA合成酶的编辑活动.
- 工程酶稳定地将异糖化异黄素转化为tRNALeu.
- 证明了产生非标准氨基酸的错误充电tRNA池的潜力.
结论:
- 工程化leucyl-tRNA合成酶为错误充电tRNA提供了一种稳定的方法.
- 这些酶是体外翻译和定制蛋白质合成的宝贵工具.
- 开发的系统为创建正交tRNA合成酶/tRNA对提供了一个支架.
相关概念视频
Types of RNA
Overview
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in the regulation of gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA...
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in the regulation of gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA...
Transfer RNA Synthesis
One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
Transcription Attenuation in Prokaryotes
Transcriptional attenuation occurs when RNA transcription is prematurely terminated due to the formation of a terminator mRNA hairpin structure. Bacteria use these hairpins to regulate the transcription process and control the synthesis of several amino acids including histidine, lysine, threonine, and phenylalanine. Transcription attenuation takes place in the non-coding regions of mRNA.
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
RNA Editing
RNA editing is a post-transcriptional modification where a precursor mRNA (pre-mRNA) nucleotide sequence is changed by base insertion, deletion, or modification. The extent of RNA editing varies from a few hundred bases, in mitochondrial DNA of trypanosomes, to a just single base, in nuclear genes of mammals. Even a single base change in the pre-mRNA can convert a codon for one amino acid into the codon for another amino acid or a stop codon. This type of re-coding can significantly affect the...
Types of RNA
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in regulating gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA Performs Diverse...
RNA Performs Diverse...
Transfer RNA Synthesis
One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...


