フコースセンシングは,細菌の腸内コロニー化を調節する
Alline R Pacheco1, Meredith M Curtis, Jennifer M Ritchie
1Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9048, USA.
Nature
|November 20, 2012
まとめ
腸出血性Escherichia coli (EHEC) は,腸に豊富に存在する糖質であるフコースを使用して,その毒性を制御します. このフコース感知システムであるFusKRは,EHECのコロニー化と哺乳類の腸の病原性にとって極めて重要です.
科学分野:
- 微生物学 微生物学とは
- 分子生物学は分子生物学である.
- 胃腸内科 胃腸内科
背景:
- 哺乳類の腸は,競争する微生物の環境である.
- 病原体植民には,栄養素の採取,信号感知,毒性の遺伝子調節が必要です.
- 腸出血性Escherichia coli (EHEC) は,ウイルス性に対する王国間のシグナリングを利用しています.
研究 の 目的:
- EHECにおける新しい化学センサーシステムを特定する.
- EHECの毒性および植民地化におけるフコースセンシングの役割を調査する.
- 腸内の微生物群とEHECの相互作用を解明する.
主な方法:
- 2つの構成要素からなる新しいシステム,FusKR (FusKセンサーキナーゼ,FusR応答調節体) の特徴.
- FusKのフコースセンシング能力の分析.
- EHEC腸内コロニゼーションに対するFusKRシステムの要求の評価.
- バクテロイドス・テタイオタオミクロンの作用を調査し,フコース経由でEHECの毒性を活性化させる.
主要な成果:
- EHECでは,新しいフコースセンシングの2コンポーネントシステム,FusKRが特定されました.
- FusKRは,毒性および代謝遺伝子の発現を制御する.
- FusKRシステムは,哺乳類の腸の堅固なEHEC植民に不可欠です.
- Bacteroides thetaiotaomicronはムシンからフクゾースを割って,EHECのFusKRシステムを活性化し,毒性の遺伝子発現を調節する.
結論:
- EHECはFusKRシステムを用いて,腸内で容易に入手できる栄養素であるフコースを感知して利用します.
- 微生物群によるフコースの利用可能性は,EHECの病原性および代謝に影響を与える.
- この研究は,EHECが宿主環境に適応するメカニズムを明らかにし,共生細菌によって提供される宿主由来信号を感知する.
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