Listeria monocytogenesの病原性のために不可欠なリステリオリシンOのPESTのような配列
1Department of Molecular and Cell Biology, Division of Infectious Diseases, School of Public Health, University of California, Berkeley, CA 94720, USA.
まとめ
Listeria monocytogenes listeriolysin O (LLO) のPESTのような配列は,病原体の毒性にとって極めて重要です. この配列は,LLOの分解を標的とし,宿主細胞の損傷を防止し,細胞内生存を可能にします.
科学分野:
- 微生物学 微生物学とは
- 細胞生物学 細胞生物学
- 病原体と宿主の相互作用
背景:
- 細胞内病原菌は,宿主細胞内の生存と複製のために保護されたニッチを必要とします.
- Listeria monocytogenesは,感染サイクル中に毛穴形成タンパク質のリステリオリシンO (LLO) を利用しています.
研究 の 目的:
- LLOの機能,ウイルス性,細胞内分割におけるPESTのような配列の役割を調査する.
- この配列が宿主細胞とのLLOの相互作用に与える影響を決定する.
主な方法:
- サイト・ディレクテッド・ミュータゲネシスで,PESTのような配列が欠けているLLO変異体を作ります.
- 宿主細胞への細菌の侵入と,その後の細胞内運命を分析する.
- 宿主細胞の生存能力と完全性の評価.
- PESTのような配列を別のサイトリシン,パーフリンゴリシンOに機能的に転送する.
主要な成果:
- PESTのような配列を欠いたLLO変異体は宿主細胞内に侵入したが,宿主細胞の浸透と死を引き起こした.
- PESTのような配列が欠けているLLOは宿主細胞溶液に蓄積され,それが分解のためにLLOをターゲットにしていることを示しています.
- PESTのような配列をperfringolysin Oに転送すると,それが無毒になり,細胞内成長を促進します.
結論:
- LLOのPESTのような配列は,Listeria monocytogenesの毒性および適切な細胞内分割のために不可欠です.
- この配列はLLOの分解を媒介し,宿主細胞の早期溶解を防止し,病原体の生存を促進します.
- PESTのような配列は,機能的に他のサイトリシンに転送され,その毒性を調節し,細胞内成長を促すことができます.
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