カチオン結合の多剤および有毒化合物の挤出トランスポーターの構造
Xiao He1, Paul Szewczyk, Andrey Karyakin
1Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, CB105, La Jolla, California 92037, USA.
Nature
|September 24, 2010
まとめ
研究者らは,植物代謝物輸送と薬剤耐性において極めて重要なMATEトランスポーターの構造を決定した. これは,外向きの形状と,他の多剤耐性トランスポーターとは異なるユニークな構造を明らかにします.
科学分野:
- バイオケミストリー バイオケミストリー
- 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:
- 多剤および有毒化合物挤出 (MATE) 家族のトランスポーターは,植物における代謝物輸送に不可欠であり,様々な生物における多剤耐性 (MDR) を媒介する.
- MATEトランスポーターは,MDRトランスポーターの最後の未定のクラスであり,作物の収穫量と医薬品の有効性に影響を与えます.
- これらのトランスポーターは,基板輸送を電気化学的グラデーションに結合させます.
研究 の 目的:
- Vibrio choleraeからのMATEトランスポーターNorMのX線構造を決定する.
- MATEトランスポーター機能の構造的基礎とそのユニークなトポロジーを解明する.
- 潜在的なカチオン結合部位とその輸送機構との関係を特定する.
主な方法:
- X線結晶学を用いて,NORMトランスポーターの構造を決定した.
- 構造分析を行い,トランスメブランヘリクや潜在的な結合部位などの重要な特徴を特定しました.
主要な成果:
- NorMのX線構造は3.65 Åに決定され,外向きの形状を明らかにした.
- 構造は,他の既知のMDRトランスポーターとは異なる12のトランスメブランヘリクを持つユニークなトポロジーを示しています.
- 輸送に重要な残留物の近くでカチオン結合部位が特定され,基板結合または輸送調節における役割を示唆しています.
結論:
- 決定された構造は,MATEトランスポーターの形状を初めて垣間見ることができます.
- 独特の構造的特徴と特定されたカチオン結合部位は,輸送機構の洞察を提供します.
- この構造情報は,植物生理学と薬剤耐性におけるMATEトランスポーター機能を理解するために不可欠であり,将来の薬剤開発を導く可能性があります.
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