ヒトの腸内細菌には 既得の細菌間防御システムがあります
Benjamin D Ross1, Adrian J Verster2, Matthew C Radey1
1Department of Microbiology, University of Washington, Seattle, WA, USA.
Nature
|November 1, 2019
まとめ
腸内細菌の獲得された細菌間防御 (AID) 遺伝子クラスターは,有毒なタンパク質攻撃から保護します. バクテロイドで発見されたこれらの移動性遺伝子群は 細菌の敵対性を中和させることで 人間の腸内微生物群を形作ります
科学分野:
- 微生物学
- ゲノミクス
- 人間の微生物群の研究
背景:
- ヒトの腸内微生物の構成は 食事や宿主の免疫だけでなく 微生物の相互作用によって影響を受けます
- 腸内細菌は,タイプVI分泌システム (T6SS) を含む,直接的な対抗メカニズムを持っています.
- T6SSは細菌の細胞間で 有毒なエフェクターを送り込み コミュニティの構造に影響を与えます
研究 の 目的:
- ヒトの腸内バクテロイドの 獲得した細菌間防御 (AID) 遺伝子群を調査する.
- これらのクラスターがバクテリアの対抗性や微生物群の生態学における役割を理解する.
- 特定のサブタイプ,リコンビネーゼ関連AID (rAID-1) の構造と機能を特徴付ける.
主な方法:
- バクテロイドゲノムにおけるAID遺伝子クラスタを特定するためのバイオ情報分析.
- AIDクラスターによる毒素耐性を評価するための in vitro 実験.
- グノトビオティックマウスのモデルで,AIDの機能をin vivoで検証する.
- rAID-1遺伝子クラスターの構造分析
主要な成果:
- ヒトの腸内細菌のAID遺伝子群の発見 免疫遺伝子をコードする
- AIDクラスターがT6SS媒介の対抗性を与えることを示した.
- 移動要素のAIDクラスターの移動性を証明し,水平の遺伝子転送を可能にします.
- rAID-1亜型の特定と検証,広範な分布と活性遺伝子獲得の証拠を示す.
結論:
- AIDシステムはバクテリアの敵対性を中和し 人間の腸内微生物群の形成に 重要な役割を果たします
- 移動性AIDクラスターは腸内環境における細菌の適応と生存に寄与する.
- この発見は 微生物の生態学における 細菌間戦争と防御の重要性を強調しています
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