等离子体复制启动蛋白TrfA抑制宿主类型III分泌系统在Pseudomonas aeruginosa中
Yu Zhang1, Liwen Yin1, Qi Liu1
1State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China.
mBio
|November 5, 2025
概括
等离子体复制蛋白TrfA抑制了 Pseudomonas aeruginosa 中的第三类分泌系统 (T3SS) 基因表达. 这一发现揭示了等离子体蛋白如何调节宿主染色体基因,从而影响细菌的病原性.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 细菌病原体的产生
背景情况:
- Pseudomonas aeruginosa 是一种机会性病原体,引起各种人类感染.
- 第三类分泌系统 (T3SS) 对于急性P. aeruginosa的病变产生至关重要.
- T3SS表达是由主激活器ExsA进行调节的.
研究的目的:
- 为了研究等离子体复制启动蛋白TrfA在P. aeruginosa基因表达中的作用.
- 阐明TrfA影响T3SS调节的机制.
- 为了确定TrfA对细菌病原性的影响.
主要方法:
- 在TrfA的存在下评估T3SS基因表达.
- 在小鼠急性肺炎模型中评估细菌致病性.
- 分析TrfA与P_exsC发起者结合的情况.
- 研究PA5530和cAMP水平的作用.
主要成果:
- 在P. aeruginosa中,TrfA作为T3SS基因表达的抑制剂.
- 在体内,TrfA可以降低细菌的病原性.
- TrfA对PA5530进行上调,导致cAMP和T3SS表达的减少.
- TrfA直接结合并调节P_exsC促进体.
结论:
- 等离子体复制启动蛋白TrfA是P. aeruginosa中T3SS的新型抑制剂.
- TrfA影响宿主染色体基因表达,影响病毒性.
- 这项研究强调了塑体和细菌致病性之间的新监管联系.
相关概念视频
Repressible Operon: trp Operon
1.3K
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...
1.3K
Mechanism of Conjugation
781
Bacterial conjugation is a mechanism of horizontal gene transfer that enables the exchange of genetic material between bacterial cells through direct contact. This process is facilitated by a donor cell carrying a conjugative plasmid, which encodes genes necessary for pilus formation, DNA replication, and transfer. The conjugative plasmid plays a central role in initiating and executing the transfer of genetic material.The tra region of the conjugative plasmid encodes proteins responsible for...
781
Gram-negative Bacterial Protein Secretion Systems
748
Gram-negative bacteria utilize sophisticated protein secretion systems to transport proteins across their double-membrane envelope into the extracellular environment or host cells. Based on their mechanism of action, these systems are classified into one-step and two-step pathways.One-Step Secretion Systems (Types I, III, IV, and VI)One-step secretion systems bypass the periplasm entirely, forming a continuous channel that spans both the inner and outer membranes:Type I Secretion System (T1SS):...
748
Prokaryotic Transcriptional Activators and Repressors
25.1K
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...
25.1K
Gene Regulation in Microbial Communities: Quorum Sensing
497
Quorum sensing is a mechanism of bacterial communication that enables coordinated gene expression in response to changes in population density. This facilitates collective behaviors that enhance survival, resource acquisition, and ecological adaptation. This process relies on small signaling molecules called autoinducers that accumulate as bacterial populations grow. When a critical threshold concentration of autoinducers is reached, bacterial cells collectively modify gene expression,...
497
Transcription Attenuation in Prokaryotes
18.1K
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...
18.1K


