ヒトの腸共生体による食用グルコシノレートの活性化のための代謝経路
Catherine S Liou1, Shannon J Sirk1, Camil A C Diaz1
1Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA.
Cell
|February 22, 2020
まとめ
Bacteroides thetaiotaomicronのような腸内細菌は,ブラシカ野菜のグルコシノレートを,がんを予防するイソチオシアナートに代謝する. この研究は,この重要な代謝過程に責任を持つ特定の遺伝子を特定します.
科学分野:
- 微生物学
- 生物化学
- 栄養学
背景:
- ブラシカ野菜に含まれるグルコシノレートは 癌のリスク低下と関連しています
- 腸内微生物群は,グルコシノレートを有益な化合物に代謝する役割を果たします.
- イソチオシアナートは,グルコシノレートから得られた化学予防代謝産物です.
研究 の 目的:
- 腸内細菌によるグルコシノレート活性化の背後にある遺伝的および生化学的メカニズムを特定する.
- バクテロイドス・テテオトオミクロンが食中のグルコシノラートを処理する役割を理解する.
主な方法:
- Bacteroides thetaiotaomicronにおける全ゲノムトランポゾン挿入スクリーン
- 細菌の遺伝子発現分析
- インビトロ酵素測定法
- モノコロニー化したマウスの胃腸イソチオシアネート産生測定
主要な成果:
- オペロン (BT2159-BT2156) は,B. thetaiotaomicronのグルコシノレート代謝に不可欠であると特定されました.
- これらの遺伝子の発現は,Bacteroides fragilisにグルコシノレート代謝能力を授与した.
- イソチオシアネートの形成には,特定の酵素 (BT2158,BT2156またはBT2157) が必要です.
- 特定の変異体 (BtΔ2157) はイソチオシアネート産生を in vivoで減少させた.
結論:
- Bacteroides thetaiotaomicronは,グルコシノレート代謝のための定義された遺伝的経路を有しています.
- この経路は,食事中のグルコシノレートから化学予防性イソチオシアナートの生成を可能にします.
- この発見は 栄養素の処理と癌の予防における 主体微生物の相互作用を明らかにしています
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