細菌間毒素は, (p) ppAppを合成することによって,標的細胞の成長を阻害する
Shehryar Ahmad1,2, Boyuan Wang3, Matthew D Walker2
1Michael DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada.
Nature
|November 8, 2019
まとめ
Pseudomonas aeruginosaは新しい毒素 Tas1 を使用し,競合する細胞死を誘導します. Tas1は (p) pAppを生成し,代謝を妨害し,ATPを枯渇させる.
科学分野:
- 微生物学
- バクテリア病原性
- 分子生物学
背景:
- バクテリアは,タイプVI分泌システム (T1SS) を含め,競合他社と敵対する様々な戦略を採用しています.
- T1SSエフェクターはしばしば細胞包膜の整合性を標的とするが,他の成長阻害メカニズムは理解されていない.
- 信号分子 (p) ppGppは,ストレス中に細菌の増殖を制御する.
研究 の 目的:
- Pseudomonas aeruginosaにおける新しいT1SSエフェクターを特定し,特徴づけること.
- 特定されたエフェクタ Tas1 の作用メカニズムを明らかにする.
- 代謝産物 (p) ppAppがバクテリアの抗生物質として果たす役割を調査する.
主な方法:
- Tas1の結晶構造の決定
- Tas1の活性度を測定する酵素測定法
- Tas1投与時の標的細胞の代謝分析
- 細胞の生存能力と代謝経路の評価
主要な成果:
- P. aeruginosaのT1SSエフェクターであるTas1が特定されました.
- Tas1は,アデノシンヌクレオチドから高い割合で (p) ppAppを生成する,パイロフォリラーゼ活性を示す.
- Tas1の投与は,標的細胞における迅速な (p) pAppの蓄積,ATPの枯渇,そして代謝失調につながる.
- これは競合する細菌の急速な細胞死につながる.
結論:
- Tas1と (p) pAppによって媒介される新しい細菌間対抗メカニズムが説明されています.
- Tas1はニュークレオチド代謝を標的とする新しい種類の細菌毒素を表しています.
- (p) ppAppはバクテリアの競争における重要な代謝産物として特定されています.
さらに関連する動画
関連する概念動画
01:23Stringent Response in E. coli
250
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...
250
01:28Gene Regulation in Microbial Communities: Quorum Sensing
443
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,...
443
01:23Antimicrobial Proteins
12.8K
Antimicrobial proteins are important components of the immune system. They aid the body in combating pathogens by either killing them directly or hindering their replication processes. Four main types of antimicrobial substances are interferons, the complement system, iron-binding proteins, and antimicrobial proteins.
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
12.8K
01:23Negative Regulator Molecules
38.2K
Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
38.2K
01:23Types of RNA
72.3K
Overview
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in the regulation of gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA...
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in the regulation of gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA...
72.3K
02:42Transcription Attenuation in Prokaryotes
18.0K
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...
18.0K