制御された毒性は,病原体が腸内微生物群と競争する能力を制御する
Nobuhiko Kamada1, Yun-Gi Kim, Ho Pan Sham
1Department of Pathology and Comprehensive Cancer Center, The University of Michigan Medical School, Ann Arbor, MI 48109, USA.
Science (New York, N.Y.)
|May 15, 2012
まとめ
腸の病原体植民は,細菌の毒性と腸内微生物との競争によって制御されます. コンメンサルは,似たような炭水化物を利用することで,Citrobacter rodentiumを上回ります.
科学分野:
- 微生物学 微生物学とは
- 病原体と宿主の相互作用
- 腸内微生物群 (gut microbiome) とは,腸内微生物群 (gut microbiome) とは,腸内微生物群 (gut microbiome) とは,腸内微生物群 (gut microbiome) とは
背景:
- 腸内病原菌のコロニー化メカニズムは完全に理解されていません.
- Citrobacter rodentiumは,バクテリアを結合して消去することによって,ヒトの感染症のモデルとして機能します.
研究 の 目的:
- Citrobacter rodentiumの腸内植民地化における毒性の遺伝子発現と微生物の競争の役割を明らかにする.
- 病原菌を上回るコンメンサルバクテリアを可能にする要因を調査する.
主な方法:
- 細菌のない,従来の方法で育てられたマウスモデルを使用した.
- 感染中にCitrobacter rodentiumの毒性の遺伝子発現をモニターする.
- 評価された病原体と,様々な炭水化物での共生生長.
主要な成果:
- 細菌のないマウスは,従来の方法で飼育されたマウスとは異なり,Citrobacter rodentiumを根絶することができなかった.
- ウイルス性遺伝子の発現は,感染後期に減少し,病原体が膜に移動する.
- コンメンサル菌はCitrobacter rodentiumを凌駕し,部分的には炭水化物の利用を共有したためです.
結論:
- バクテリアの毒性と種間の代謝競争は,腸内病原菌のコロニー化の重要な調節因子である.
- コンメンサルバクテリアは,競争的排除を通じて病原体負荷を制御する上で重要な役割を果たします.
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