一个快速有效的策略,用于对大肠杆菌中多个基因的组合抑制
Yi Zheng1, Yuxia Mo1, Yingbo Yuan1
1State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, People's Republic of China.
Microbial cell factories
|March 28, 2025
概括
这项研究引入了一种新的CRISPR干扰 (CRISPRi) 系统,用于有效调节大肠杆菌中的多个基因. 优化的系统通过微调基因表达来显著提高N-乙神经胺酸 (NeuAc) 的产生.
科学领域:
- 代谢工程是代谢工程.
- 合成生物学 合成生物学
- 微生物生物技术 微生物生物技术
背景情况:
- 在代谢工程中,CRISPR干扰 (CRISPRi) 对于调节基因表达至关重要.
- 为组合基因调节构建众多单导向RNA (sgRNA) 表达等离子体具有挑战性.
研究的目的:
- 开发一种高效的组合抑制系统,用于对大肠杆菌的多基因调节.
- 为了简化SgRNA表达等离子体的构建和应用,用于代谢工程.
主要方法:
- 开发了一种修改后的金门组装方法,用于快速构建sgRNA表达等离子体 (p3gRNA-LTA).
- 优化诱导性促进体和sgRNA处理序列,以最大限度地减少泄漏的基因抑制.
- 将该系统应用于对大肠杆菌中三种基因 (pta,ptsI,pykA) 的组合抑制.
主要成果:
- 成功地减轻了来自泄漏sgRNA表达的不必要抑制.
- 使用不同的诱导剂,证明了对组合基因抑制效应的快速评估.
- 通过最佳的基因抑制,N-乙神经胺酸 (NeuAc) 产量增加了2.4倍.
结论:
- 开发的组合抑制系统简化了工程菌株中的多基因调节.
- 这种系统有助于微调新陈代谢途径以提高产品产量.
相关概念视频
Prokaryotic Transcriptional Activators and Repressors
The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Transcription of prokaryotic...
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Operon Model
The operon model represents a fundamental mechanism of gene regulation in prokaryotes, enabling coordinated expression of genes involved in related metabolic or functional pathways. Operons consist of structural genes, a promoter, and an operator, with transcription regulated by repressors, activators, and small effector molecules.Structure and Function of OperonsAn operon is a cluster of structural genes transcribed together under the control of a single promoter. The promoter region...
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The trp operon in Escherichia coli exemplifies a repressible operon. It regulates the synthesis of tryptophan through repressor-mediated transcriptional control and attenuation. This dual regulatory mechanism ensures tryptophan biosynthesis occurs only when needed, conserving cellular resources.Structure of the trp OperonThe trp operon consists of five structural genes (trpE, trpD, trpC, trpB, and trpA) that encode enzymes for tryptophan biosynthesis. These genes are transcribed as a single...
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Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...


