PAAR-リピートタンパク質は,タイプVI分泌システムのスパイクを鋭くし,多様化させます
Mikhail M Shneider1,2, Sergey A Buth1, Brian T Ho3
1École Polytechnique Fédérale de Lausanne (EPFL), BSP-415, 1015 Lausanne, Switzerland.
Nature
|August 9, 2013
まとめ
PAARリピートスーパーファミリーのタンパク質は,タイプVI分泌システム (T6SS) のスパイクを鋭くし,細菌細胞が毒素を放出し,獲物を殺すことができます. この発見は,細菌の捕食におけるT6SS機能の新しいモデルを明らかにしています.
科学分野:
- 微生物学 微生物学とは
- バクテリア病原菌の発生
- 分子生物学は分子生物学である.
背景:
- バクテリアのタイプVI分泌システム (T6SS) は,グラム陰性細菌の生態学的相互作用に不可欠な複雑な機械です.
- T6SSは,有毒なエフェクターをプロカリオット細胞とエウカリオット細胞に届けるのを促進し,捕食を可能にします.
- T6SSの正確な組成とエフェクター伝達メカニズムは,依然としてほとんど不明です.
研究 の 目的:
- T6SSにおけるPAARタンパク質の構造的役割を明らかにする.
- T6SSによるエフェクターの固定と配送のメカニズムを理解する.
- バクテリアの捕食のためのT6SSオルガネルの完全な構造を明らかにするために.
主な方法:
- X線結晶学を用いたタンパク質構造分析.
- T6SS媒介による分泌と殺菌におけるPAARタンパク質の機能を調査する.
- Vibrio choleraeとAcinetobacter baylyiをモデル生物として利用しています.
主要な成果:
- PAAR (プロリン・アラニン・アラニン・アルギニン) スーパーファミリーのタンパク質は,VgrGのスパイクに鋭い円筒状の延長を形成します.
- PAARタンパク質は,V. choleraeとA. baylyi.でT6SS媒介による分泌と標的細胞の破壊に不可欠である.
- 結晶構造は,VgrGのようなパートナーに結合するPAARタンパク質を明らかにし,スパイク複合体を鋭くし,エフェクタ結合を容易にします.
結論:
- PAARタンパク質は,T6SS VgrGのスパイクを鋭くする重要な成分であり,捕食器の重要な部分を形成します.
- T6SSオルガネルの新しいモデルが提案され,VgrG-PAARスパイク複合体は複数のエフェクターを同時に提供します.
- このメカニズムは,効率的で同時に毒素を放出し,細菌の捕食能力を高めます.
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