トランスロコン・アセンブリによって引き起こされるディスルファイドの再編成は,リポポリサッカリドの輸出を制御する
Shu-Sin Chng1, Mingyu Xue, Ronald A Garner
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|September 1, 2012
まとめ
グラム陰性細菌におけるリポポリサッカリド輸送タンパク質D (LptD) の折りたたみには,2つのタンパク質複合体が必要です. LptEタンパク質は,LptDのディスルファイド結合の再編成を誘発する.
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
- バイオケミストリー バイオケミストリー
背景:
- リポポリサッカリド (LPS) は,グラム陰性細菌の外膜の完全性および生存能力にとって不可欠です.
- LptDタンパク質は,バクテリアの外膜にLPSの転位を促進します.
- LptDはLptEと複合体を形成し,LPSトランスロコンを作成します.
研究 の 目的:
- LptDタンパク質の in vivo 酸化折り畳み経路を調査する.
- LptDの組立と機能におけるジスルファイド結合の役割を明らかにする.
- LptD成熟におけるLptEタンパク質の貢献を理解するために.
主な方法:
- LptDの折りたたみの中間物質のインビボ特性.
- ディスルファイド結合の形成と再配置の分析.
- LptD-LptE複合体の形成と機能を評価するための生化学的分析.
主要な成果:
- 酸化折り畳み経路におけるLptDの7つの異なるin vivo状態が特定されました.
- LptDの適切な組み立て中に,非原生ジルフイドを含む非機能的中間物質が観察されました.
- オキシダゼDsbAが中間生成に必要であり,LptEは原生ジスルファイド形式への成熟を誘発した.
結論:
- LptDのディスルファイド結合依存の折り畳みは,その機能にとって極めて重要です.
- LptD-LptE複合体の適切な組み立ては,二硫化物結合の再編成とLptD成熟のために不可欠です.
- この研究は,外膜タンパク質の折りたたみとバクテリアの複雑な組み立てのための新しいメカニズムを明らかにしています.
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