ボルデッラの固有マイナーコンフォマー BteA 指示チャペロン媒介展開
Adi Yahalom1, Hadassa Shaked1, Sharon Ruthstein1
1Department of Chemistry, Bar Ilan University, Ramat Gan 52900, Israel.
Journal of the American Chemical Society
|June 24, 2022
まとめ
宿主細胞への注射のためのエフェクタ BteAを展開する. 構造研究により,BtcAはより広範なBteA構造を誘発し,タイプ3の分泌システム機能に不可欠である.
科学分野:
- 微生物学
- 構造生物学
- 分子 機構
背景:
- Bordetella pertussisは,宿主細胞にBteAのような細胞毒性エフェクターを送り込むために,タイプ3の分泌システム (T3SS) を利用する.
- エフェクタBteAは,T3SS針を通して注射される前に,その伴奏者BtcAによって展開されていると考えられています.
研究 の 目的:
- シェーパーロンBtcAがエフェクタBteAの展開を媒介する分子メカニズムを解明する.
- BtcAに結合すると BteAの形状の変化を理解する.
主な方法:
- 核磁共振 (NMR) スペクトロスコーピー
- 電子パラマグネティック共振 (EPR) スペクトロスコーピー
- NMR リラクゼーション分散実験
主要な成果:
- BtcA結合はBteAの全体的な構造変化を誘導し,より拡張された部分的に展開された形状につながります.
- EPR測定により,自由BteAは構造化された形態と軽微な展開された種の間の構造的均衡に存在することが明らかになった.
- NMRのリラクゼーション分散は,BtcAの結合によって影響を受け,形状の均衡に関与するBteAの特定の表面を特定した.
結論:
- この発見は,BtcAが,BteAの特定の,より構造的でない形状に優先的に結合し,安定させる形状選択性メカニズムを示唆している.
- このメカニズムは,BteAの効率的な展開とT3SS経由の注入に不可欠です.
- 特定されたメカニズムは,関連する細菌分泌システムにおけるエフェクター-チャペロン相互作用の共通のパラダイムを表す可能性があります.
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