本質的に無秩序なタンパク質糸は,細菌の外膜ポリンOmpFFを通過する
Nicholas G Housden1, Jonathan T S Hopper, Natalya Lukoyanova
1Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
まとめ
バクテリオシンコリシンE9 (ColE9) はOmpFポリンを使用して,細胞への侵入のためのトランスロコンを形成します. 本質的に無秩序なタンパク質ドメインがOmpFの毛穴を通過して細胞死を誘発する.
科学分野:
- 微生物学 微生物学とは
- 構造生物学 構造生物学とは
- 分子生物学は分子生物学である.
背景:
- ポーリンは,溶液輸送に不可欠な外膜タンパク質であり,細胞死に関与しています.
- コリシンE9 (ColE9) のようなバクテリオシンは,細菌を標的とするタンパク質毒素である.
- OmpFポリンは,Escherichia coli.の外膜の重要な成分である.
研究 の 目的:
- OmpF porinを用いてコリシンE9が細胞毒性トランスロコンを組み立てるメカニズムを調査する.
- ColE9の本質的に無秩序なN末端ドメインがOmpFと相互作用して細胞のインポートを開始する方法を解明する.
主な方法:
- Escherichia coliの表面に ColE9-OmpF トランスロコンの組み立てを研究しました.
- タンパク質とタンパク質の相互作用を分析するために,構造的および生化学的技術を活用しました.
主要な成果:
- コリシンE9のN端ドメインは,2つのOmpFサブユニットを通って反対方向にスレッドします.
- このスレッドは,ターゲットであるTolBタンパク質を固定された方向で捕捉し,コリシンインポートを開始します.
- 本質的に無秩序なタンパク質が狭いポリン経路を通過できることを示した.
結論:
- コリシンE9はOmpFのポリン構造を利用して,細菌細胞への侵入のためのトランスロコンを形成します.
- このメカニズムは,本質的に無秩序なタンパク質ドメインがポリンを通ってトンネルを掘り起こし,細胞死亡のシグナルを伝達することを含む.
関連する概念動画
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Cotranslational Protein Translocation
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Sec61 channel partners for cotranslational translocation
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Two models describe the mechanism of precursor recognition and entry across the outer membrane through the TOC complex. Model 1 suggests the newly synthesized precursor binds to the TOC receptor 159 and forms a complex.
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Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.


