外膜トランスロコンは内膜ATPアゼと通信し,リポポリサカリド輸送を停止する
Ran Xie1, Rebecca J Taylor1, Daniel Kahne1
1Department of Chemistry & Chemical Biology , Harvard University , 12 Oxford Street , Cambridge , Massachusetts 02138 , United States.
Journal of the American Chemical Society
|September 27, 2018
まとめ
グラム陰性細菌の外膜組成は,リポポリサカリド (LPS) 輸送に依存しています. 外膜トランスロコンの親和感とネガティブなフィードバックは,この重要なLPS伝達プロセスを調節します.
科学分野:
- バクテリアの細胞包膜の生化
- 膜タンパク質の輸送
- 分子微生物学
背景:
- グラム陰性細菌は 生存に不可欠な独特の非対称外膜を持っています
- この外側の膜は 抗生物質を含む有毒な分子に対する 障壁として機能します
- リポポリサッカリド (LPS) は,この膜の外側を構成し,タンパク質ブリッジで輸送されます.
研究 の 目的:
- リポポリサッカリド (LPS) 輸送を監視するための光測定法を開発し,使用する.
- バクテリアの外膜に LPS の伝達を制御する調節メカニズムを調査する.
- LPS輸送における外膜トランスロコンとATP水解の役割を理解する.
主な方法:
- LPS輸送のための光測定法の開発.
- プロテオリポソームを使って 細菌の内外膜を模倣します
- 制御メカニズムを研究するために LPS 輸送装置の変異体を使用します
主要な成果:
- LPSは,外膜プロテオリポソームの外側の小葉にうまく送られます.
- 輸送停止は内膜基板が枯渇する前に起こります.
- LPS輸送の調節は,LPSとATPの水解に対する外膜トランスロコンの親和性に関連しています.
結論:
- LPSに対する外膜トランスロコンの親和性は,最終的な投与量を決定する.
- ATPの水解はLPSの供給に依存し,規制されたプロセスを示す.
- 外側から内側の膜への負のフィードバックは,LPS輸送の長距離制御を提供します.
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