展開されたポリペプチドが,細菌のIII型分泌において,同類のシャペロンによって維持される
1Section of Microbial Pathogenesis, Boyer Center for Molecular Medicine, Yale School of Medicine, New Haven, Connecticut 06336, USA.
Nature
|November 2, 2001
まとめ
バクテリアのIII型分泌システムは,宿主細胞にエフェクタータンパク質を供給するために,チャペロンを使用します. サルモネラ SptP エフェクタータンパク質
科学分野:
- 微生物学と分子生物学について
- バクテリア病原菌の発生
- タンパク質分泌システム
背景:
- 細菌の病原体は,第3型タンパク質分泌システム (T3SS) を用いて,受容体細胞にエフェクタータンパク質を注入する.
- これらのエフェクタータンパク質は宿主細胞の機能を調節し,ウイルス性に貢献します.
- サイトソリックチャペロンは,多くのT3SSエフェクタータンパク質の転位に不可欠です.
研究 の 目的:
- T3SSエフェクタータンパク質とのシャペロン相互作用の構造的基礎を解明する.
- チャペロンがT3SS経由でエフェクタータンパク質の転位をどのように促進するのかを理解する.
主な方法:
- サルモネラエフェクタータンパク質SptPのシャペロン結合ドメインの結晶構造を,そのシャペロンSicPと複合した1.9 Å解像度で決定した.
主要な成果:
- SptPチャペロン結合ドメインは,拡張され,展開された形状を採用しています.
- 3つのSicPチャペロン分子は,SptPドメインに順次結合する.
- チャペロンは,水害性のインターフェイスを介して,異なるSptPセグメントの二分化を促進します.
結論:
- T3SSチャペロンは,エフェクタータンパク質を分泌に適した,展開された,または部分的に折れた状態で維持します.
- このチャペロン介的形状は,転位のためのT3SS機械との関わりを容易にする.
- シェーパロン・エフェクタ相互作用に関する構造的洞察は,細菌の毒性のメカニズムを理解する鍵となる.
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