サブストラットは,タイプVII分泌のマルチドメインATPアゼモーターのマルチメリゼーションと活性化を制御する
Oren S Rosenberg1, Dustin Dovala2, Xueming Li3
1Division of Infectious Diseases, Department of Medicine, UCSF Medical Center, University of California, San Francisco, San Francisco, CA 94143-0654, USA.
Cell
|April 14, 2015
まとめ
タイプVIIタンパク質分泌 (T7S) システムは,機能するためにすべての基板を必要とします. サブストラットEsxB結合は,アロステリックではなく,マルチメリゼーションを刺激することによって,トランスロカースEccCを活性化します.
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:
- タイプVIIタンパク質分泌 (T7S) は,Mycobacterium tuberculosisやStaphylococcus aureusのような細菌の毒性にとって不可欠である.
- T7Sシステムは,すべての分泌基板が活性化することを要求し,複雑な規制メカニズムを示唆しています.
研究 の 目的:
- 構造生物学を用いてT7SトランスロカースEccCとその基板EsxBの機能を解明する.
- T7Sにおける基板相互依存のメカニズムを理解する.
主な方法:
- X線結晶学を用いて,EccCトランスロカゼの構造を決定した.
- EccCとEsxBの相互作用を研究するために生化学的測定が行われました.
主要な成果:
- EccCの結晶構造は,酵素活性を調節する3つのATPアゼドメイン間の相互作用を明らかにした.
- EsxBは,EccCのC端のATPアゼドメインと結合し,その活性性を高めます.
- 基板結合は,アロステル調節ではなく,マルチメリゼーションによってEccCを活性化します.
結論:
- EsxB基板はT7S機構の不可欠な構成要素であり,基板の相互依存性を説明する.
- 基板結合が細菌からの協調的な放出を調節するモデルが提案されています.
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