細菌の転位チャネルを通過するタンパク質の折り畳み中間体を検出する
Hiroshi Kadokura1, Jon Beckwith
1Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA. hkadokura@bs.naist.jp
Cell
|September 22, 2009
まとめ
この研究は,細菌のタンパク質の折りたたみの中間体を特定し,転位モードが周回プラズマの折りたたみにどのように影響するかを明らかにします. リボソーム活動は,細胞の外でもタンパク質の折り畳みを調節することができます.
科学分野:
- 細菌のタンパク質の折りたたみ
- 分子生物学は分子生物学である.
- 細胞および膜生物学 細胞および膜生物学
背景:
- ほとんどのバクテリアの輸出タンパク質は,細胞質膜を展開して横切ります.
- トランスロケーション中にタンパク質の折りたたみ中間物質を検出することは困難です.
研究 の 目的:
- 周辺プラズマタンパク質のコトランスレーションおよびポストトランスレーションの折り畳み中間体を識別する.
- 転位モードがペリプラズマにおけるタンパク質の折り畳みにどのように影響するかを理解する.
主な方法:
- 周辺プラズマタンパク質とDsbA.との間の混合ジスルファイド中間物質の識別
- タンパク質の折りたたみ中の二硫化物結合の形成と解消の分析.
主要な成果:
- コトランスレーションによる折りたたみ中間物質には,DsbA.との一時的な共換結合が含まれています.
- 構造ディスルフィードを形成する2つのシステインは,折り畳みにおいて異なる役割を果たすことができます.
- コトランスレーションとポストトランスレーションのトランスロケーションは,周辺プラズマタンパク質の折りたたみに影響します.
結論:
- 周辺プラズマにおけるタンパク質の折り畳みは,転位の方法によって影響を受けます.
- リボソームの活動により,タンパク質の折りたたみがエクストラサイトソリック区画で調節される.
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