简化tRNA合成酶进化为遗传码扩展和深度测序分析其进化变体的分析
ACS synthetic biology
|April 15, 2025
概括
这项研究简化了定向进化,以增强pyrrolysyl-tRNA合成酶 (PylRS) 活动,以扩展遗传密码. 这种可访问的方法改善了非正规氨基酸的结合,这对于蛋白质工程至关重要.
科学领域:
- 合成生物学 合成生物学
- 蛋白质工程是指蛋白质的工程.
- 生物化学 生物化学
背景情况:
- 遗传密码扩展 (GCE) 可以将非正规氨基酸 (ncAAs) 纳入蛋白质中,使用正交tRNA和氨基-tRNA-合成酶 (aaRS) 对.
- 虽然GCE提供了诸如标签和交叉链接等多种应用,但提高ncAA整合效率仍然是一个关键挑战.
- 定向进化是一种强大的策略,通过引入和选择有益的突变来改善aaRS活动.
研究的目的:
- 开发和介绍一种简化,可访问的定向进化系统,用于从*Methanosarcina mazei*改善pyrrolysyl-tRNA合成酶 (PylRS) 的活性.
- 发展PylRS变体,以增强特定非正规氨基酸的结合.
- 调查串联密码子随机化在改善PylRS功能的有效性.
主要方法:
- 使用基本的实验室设备实施了简化的定向进化系统.
- 进化了针对三个不同的基质的PylRS变体,产生基质特异性突变.
- 利用深度测序来分析突变,评估PylRS活动和表达,并验证进化策略.
主要成果:
- 成功进化了PylRS变体,对特定基质有了更好的活性.
- 通过定向进化途径识别出独特的基质特异性突变.
- 证明了串联密码子随机化通过附加突变效应有效地增强了PylRS功能.
- 深度测序证实了该方法的效率,并突出了协同突变的好处.
结论:
- 提出的简化定向进化系统有效地简化了PylRS.的进化过程.
- 这些发现为提高ncAA整合效率的策略提供了有价值的见解.
- 这项工作促进了合成生物学和蛋白质工程应用的进步,这些应用需要改进GCE.
相关概念视频
Transfer RNA Synthesis
11.8K
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...
11.8K
Bacterial Transcription
27.8K
RNA polymerase (RNAP) carries out DNA-dependent RNA synthesis in both bacteria and eukaryotes. Bacteria do not have a membrane-bound nucleus. So, transcription and translation occur simultaneously, on the same DNA template.
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
27.8K
Bacterial RNA Polymerase
28.1K
Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
28.1K
tRNA Activation
18.7K
Aminoacyl-tRNA synthetases are present in both eukaryotes and bacteria. Though eukaryotes have 20 different aminoacyl-tRNA synthetases to couple to 20 amino acids, many bacteria do not have genes for all of these aminoacyl-tRNA synthetases. Despite this, they still use all 20 amino acids to synthesize their proteins. For instance, some bacteria do not have the gene encoding the enzyme that couples glutamine with its partner tRNA. In these organisms, one enzyme adds glutamic acid to all of the...
18.7K
Gene Evolution - Fast or Slow?
7.0K
The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
In contrast, regions which code...
7.0K
Evolutionary Relationships through Genome Comparisons
5.6K
Genome comparison is one of the excellent ways to interpret the evolutionary relationships between organisms. The basic principle of genome comparison is that if two species share a common feature, it is likely encoded by the DNA sequence conserved between both species. The advent of genome sequencing technologies in the late 20th century enabled scientists to understand the concept of conservation of domains between species and helped them to deduce evolutionary relationships across diverse...
5.6K


