モリブデート/tungstate ABCトランスポーターにおけるトランス阻害の構造的基礎
Sabina Gerber1, Mireia Comellas-Bigler, Birke A Goetz
1Institute of Molecular Biology and Biophysics, ETH Zürich, HPK D14.3, 8093 Zürich, Switzerland.
Science (New York, N.Y.)
|May 31, 2008
まとめ
研究者らは,膜トランスポーターにおけるトランス阻害の構造的基礎を明らかにした. モリブダート/tungstateがABCトランスポーター (ModBC) に結合すると,ABCトランスポーターは内向きの状態にロックされ,基質の輸送を防ぐ.
科学分野:
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
- 分子生物学は分子生物学である.
背景:
- 膜輸送タンパク質は,細胞の機能に不可欠です.
- 基板がトランスポーター周回を阻害するトランス阻害は,明確な構造的な理解が欠けている.
研究 の 目的:
- モリブダート/tungstate ABCトランスポーターにおけるトランス阻害の構造的基礎を解明する.
- 基板結合がトランスポーターの形状と活動にどのように影響するかを理解する.
主な方法:
- X線結晶学を用いて,ModBCトランスポーターの構造を決定した.
- トランス阻害状態の結晶構造の分析.
主要な成果:
- Methanosarcina acetivoransのModBCトランスポーターのトランス阻害状態の結晶構造が決定されました.
- オキシアニオン結合ポケットは,ニュクレオチド結合サブユニットの規制ドメインのインターフェイスで特定されました.
- モリブダートまたはtungstate結合はATPaseの活性を阻害し,トランスポーターを内向きの形状にロックします.
結論:
- 基質結合 (モリブデート/チューングステート) は,アロステリック効果を誘導し,ATPase活性を抑制する.
- この阻害は,トランスポーターが内向きと外向きの状態を交互に変化させることを妨げ,輸送をブロックします.
- この研究は,ABCトランスポーターにおけるトランス阻害のための構造的メカニズムを提供する.
関連する概念動画
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