酸化タンパク質の折り畳みは,電子輸送システムによって引き起こされます
1Department of Biology, University of Michigan, Ann Arbor 48109-1048, USA.
Cell
|July 31, 1999
まとめ
細胞内の二酸化硫化物結合形成は,エネルギー生産と関連しています. DsbB酵素はキノンを用いて,タンパク質の折り畳みを電子輸送連鎖と結びつけ,さまざまな酸素レベルに適応します.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 細胞の代謝について
背景:
- ディスルファイド結合の形成は,タンパク質の折りたたみと in vivo の機能に不可欠です.
- このプロセスは主にDsbAおよびDSbBタンパク質によって触媒化されます.
- ディスルファイド結合形成と細胞のエネルギー代謝を結びつける正確なメカニズムは,まだ完全に理解されていません.
研究 の 目的:
- 精製されたDsbAとDSbBのコンポーネントを使用して, in vivoの酸化折り畳みシステムを再構成し,調査する.
- タンパク質の折り畳みを駆動する酸化力の源を特定するために.
- ディスルファイド結合形成と細胞の代謝経路,特に電子輸送連鎖の間の直接的なリンクを解明する.
主な方法:
- 浄化されたDsbAおよびDsbBタンパク質を使用して,二硫化結合形成システムの再構成.
- キノンを含むDSbBの電子受容体役割の調査.
- 異なる酸素条件下で異なる酸化酵素 (シトクロームbo,シトクロームbd) を経由する電子の流れ経路の分析.
- メナキノンが,無酸素状態で,フーマレートなどの代替受容体への電子移転における役割を調べた.
主要な成果:
- ディスルファイド結合形成は,細胞の電子伝送連鎖と直接結合しています.
- DsbBはキノンを電子受容体として利用し,柔軟な電子輸送経路を可能にします.
- このシステムは,異なる酸素の供給に適応し,特定の酸化酵素 (有酸素でシトクロームbo,部分無酸素でシトクロームbd) または代替受容体 (無酸素でフーマレート) を利用します.
- 浄化された成分は,酸化折りたたみシステムを成功裏に再構成しました.
結論:
- DsbAとDSbBによって触媒化された酸化折り畳みシステムは,細胞のエネルギー代謝と密接に統合されています.
- DsbBに関連した電子輸送経路の柔軟性は,細胞機能のための二硫化物結合形成の決定的な重要性を強調しています.
- この結合の理解は,細胞の適応とタンパク質の成熟の基本的なプロセスについての洞察を提供します.
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