バクテリアの多剤輸出者の抑制のための構造的基礎
Ryosuke Nakashima1, Keisuke Sakurai, Seiji Yamasaki
1Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan.
Nature
|July 2, 2013
まとめ
ピリドピリミジン誘導体は,水害性トラップに結合することで,多剤流出ポンプAcrBとMexBをブロックし,その機能を阻害します. この発見は,グラム陰性病原体に対する新しい抗生物質の開発に役立ちます.
科学分野:
- 構造生物学 構造生物学とは
- 微生物学 微生物学とは
- ドラッグ・ディスカバリー・ディスカバリー・ドラッグ・ディスカバリー・ドラッグ・ディスカバリー
背景:
- AcrBのような多剤流出媒体は,グラム陰性細菌の多剤耐性の鍵となる.
- 既存の流出ポンプ阻害剤は臨床的有用性がないため,新しい治療戦略が必要である.
- MexBとMexYは,重要な病原体であるPseudomonas aeruginosaの重要なマルチドラッグ輸出者です.
研究 の 目的:
- ピリドピリミジン誘導体によるAcrBとMexBの阻害の構造的基礎を決定する.
- ピリドピリミジンがこれらの流出ポンプの機能回転を阻害するメカニズムを解明する.
- 特定の阻害剤結合を可能にする構造的特徴を特定し,新しい薬の開発を導く.
主な方法:
- ピリドピリミジン誘導体によるAcrBとMexBの複合体の結晶構造の決定.
- ディスタルポケットと関連する水嫌性の特徴に焦点を当てて,阻害剤結合部位の分析.
- AcrB,MexB,および関連するトランスポーターMexY.における結合相互作用の比較.
主要な成果:
- ピリドピリミジン誘導体は,AcrBとMexBのディスタルポケットにある特定の排水性トラップに結合します.
- この結合は,薬物の流出に不可欠な機能的な回転をステリカルに阻害する.
- AcrBとMexBのフェニララニン残留物 (Phe178) は,π-π相互作用によって緊密な阻害剤結合を促進し,MexY (Trp177) のトリプトファンはその結合を防ぐ.
結論:
- 特定された水害性トラップは,ピリドピリミジンベースの阻害剤の重要な標的である.
- これらの構造的相互作用を理解することは,AcrBとMexBの強力で特定の阻害剤を設計するために不可欠です.
- この研究は,Pseudomonas aeruginosaのMexBとMexYを標的とした普遍的阻害剤の開発のための基礎を築いています.
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