MarR家族转录因子SlyA检测肠道细菌中的铁和呼吸状况
W Ryan Will1, Ferric C Fang1,2
1Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA.
mBio
|August 25, 2025
概括
细菌转录因子SlyA与芳香代谢物结合,将细胞代谢与毒性基因调节联系起来. 这一发现揭示了SlyA如何感知代谢状态以控制肠道细菌的基因表达.
科学领域:
- 微生物学
- 分子生物学
- 细菌致病性
背景情况:
- SlyA是肠道细菌中保存的转录因子,调节毒性基因,属于小分子结合的MarR家族.
- 在细菌和古生物中保存的MarR家族蛋白质涉及到感知外来生物和潜在的内源代谢物,这表明除了排放之外还有更广泛的调节作用.
- 虽然SlyA与异生菌结合,但其内源性配体和代谢传感能力在很大程度上仍未被探索.
研究的目的:
- 为了确定结合并抑制Salmonella Typhimurium中的SlyA的内源性芳香碳酸盐.
- 通过芳香碳酸盐代谢来检测SlyA在细胞代谢状态中的作用.
- 阐明SlyA如何将代谢信号集成到控制毒性和排泄的转录网络中.
主要方法:
- 在Salmonella Typhimurium中对芳香代谢基因的有针对性的分析.
- 用于测试各种芳香碳酸盐对SlyA的抑制的生物化学测试.
- SlyA活动与细胞呼吸和生长条件的相关性.
主要成果:
- 发现SlyA被多种芳香碳酸盐抑制,包括2,3-二基酸盐和4-基酸盐.
- 这些已识别的配体是重要的细胞组件的前体,如 siderophores 和电子载体.
- 这些代谢物的SlyA抑制表明它在感知铁的可用性,呼吸和代谢状态方面的作用.
结论:
- SlyA作为一种代谢传感器,将细胞状态整合到基因调节网络中.
- 芳香碳酸盐作为SlyA的关键信号分子,将代谢途径与毒性基因表达联系起来.
- 这项研究揭示了MarR家族蛋白质如何根据代谢线索调节细菌毒性的一种新机制.
相关概念视频
Gene Regulation in Microbial Communities: Quorum Sensing
92
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,...
92
Global Regulatory Systems
71
Global regulatory systems in bacteria enable rapid and coordinated responses to environmental changes by integrating sensory inputs with gene expression, ensuring efficient adaptation to fluctuating conditions. Key global regulatory mechanisms include regulons, two-component systems, sigma factors, and secondary messengers.Regulons and Global RegulatorsA regulon is a collection of genes and operons controlled by a common global regulator. These regulators enable bacteria to prioritize resource...
71
Stringent Response in E. coli
52
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...
52
Translational Regulation
92
Translational regulation in prokaryotes ensures efficient protein synthesis by controlling ribosome access to mRNA. This regulation is mediated by secondary RNA structures, including translational riboswitches, RNA thermometers, and small RNAs (sRNAs), which respond to intracellular and environmental signals to modulate gene expression.Translational RiboswitchesRiboswitches in the leader region of mRNAs can regulate translation by altering the accessibility of the Shine-Dalgarno (SD) sequence,...
92
Transcription Attenuation in Prokaryotes
16.0K
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...
16.0K
Prokaryotic Transcriptional Activators and Repressors
21.9K
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...
21.9K


