细胞外细菌病原体调节宿主新陈代谢,以调节自身的感知和增殖
Moshe Baruch1, Ilia Belotserkovsky1, Baruch B Hertzog1
1Department of Microbiology and Molecular Genetics, The Hebrew University of Jerusalem, Faculty of Medicine, Jerusalem 91120, Israel.
Cell
|January 21, 2014
概括
甲组链球菌 (GAS) 感染依赖于营养获取. 细菌感知宿主释放的阿斯巴拉金 (ASN),改变基因表达和毒性,提供治疗点.
科学领域:
- 微生物学 微生物学
- 传染性疾病 传染性疾病
- 分子生物学分子生物学
背景情况:
- 甲型链球菌 (GAS) 是一个重要的人类病原体.
- 营养素的获取对于细菌的生存和感染的进展至关重要.
- 了解GAS与宿主之间的相互作用对于开发有效的治疗方法至关重要.
研究的目的:
- 阐明阿斯巴拉金 (ASN) 在GAS病变发生中的作用.
- 为了确定由ASN调节的GAS毒性因子.
- 探索ASN新陈代谢作为潜在的治疗点来对抗GAS感染.
主要方法:
- 作为GAS的记者,利用了定数感应SIL系统.
- 研究了与宿主细胞和毒素输送的GAS相互作用.
- 分析了对ASN的反应中的基因表达变化.
- 评估了阿斯巴拉金酶对体外和体内GAS生长的影响.
主要成果:
- 气体传递链聚素毒素,诱导宿主细胞内质网膜应激.
- 宿主细胞的压力会增加ASN的产生,ASN会感知气体.
- ASN影响大约17%的GAS基因的表达,包括对 estreptolysin毒素的上调和对增殖基因的下调.
- 阿斯巴拉金酶有效地抑制了人类血液中的GAS生长和小鼠细菌病模型.
结论:
- GAS采用了一种复杂的机制,通过操纵宿主细胞应激反应来获取营养.
- ASN 作为 GAS 中的一个关键信号分子,调节毒性因子表达.
- 用阿斯巴拉金酶准ASN代谢是一种有前途的治疗策略,可以对抗GAS感染.
相关概念视频
Regulation of Bacterial Virulence
76
Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
76
Stringent Response in E. coli
528
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...
528
Defense Against Bacterial Pathogens
3.0K
The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
3.0K
Colonisation of Pathogens
77
Pathogen colonization of host tissues is a critical step in the development of infectious diseases. Various pathogenic microorganisms, including bacteria, fungi, viruses, and protozoa, have evolved complex strategies to attach to, invade, and persist within host environments. These mechanisms enable pathogens to establish infections, evade immune responses, and resist antimicrobial treatments.Attachment to Host CellsIn bacteria, colonization typically begins with adherence to host epithelial...
77
Bacterial Signaling
29.8K
Bacterial signaling can occur within bacteria (intracellular) or between bacteria (intercellular). At times, a group of bacteria behaves like a community. To achieve this, they engage in quorum sensing, the perception of higher cell density that causes changes in gene expression. Quorum sensing involves both extracellular and intracellular signaling. The signaling cascade starts with a molecule called an autoinducer (AI). Individual bacteria produce AIs that move out of the bacterial cell...
29.8K
Gene Regulation in Microbial Communities: Quorum Sensing
954
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,...
954


