C. difficileは,毒素媒介の病気で生成される宿主メタボライトを利用する
Kali M Pruss1, Justin L Sonnenburg2
1Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA.
Nature
|April 29, 2021
まとめ
炎症時にアルドース還元酵素によって生成される宿主由来ソルビトールを利用して,代謝上の利点を得る. この栄養源は 病原体自身の毒素誘発の病気に反応して生成されます
科学分野:
- 微生物学
- 病原体の代謝
- ホストと病原体の相互作用
背景:
- 腸の病原体は 宿主の炎症を利用して 代謝を促します
- Clostridium difficileは毒素媒介性大腸炎を引き起こすが,その代謝による炎症への適応は十分に理解されていない.
研究 の 目的:
- 宿主誘発の炎症におけるClostridium difficileの代謝戦略を解明する.
- 炎症性環境でC. difficileが利用する栄養源を特定する.
主な方法:
- マウスモデルでの野生型と毒素欠乏性のC. difficileのRNA配列決定
- 細菌と宿主の遺伝子を統合して宿主と病原体の代謝を研究する.
主要な成果:
- C. difficileは食事と宿主由来のソルビトールを利用する.
- ホストソルビトールは,アルドース還元酵素によって生成され,炎症時に免疫細胞で調節される.
- アルドース還元酵素の活性が,C. difficile毒素媒介の病気で増加する.
結論:
- C. difficileは,アルドース還元酵素によって生成される宿主由来ソルビトールを,自身の誘発性大腸炎で栄養素として利用する.
- これは,感染中に宿主酵素誘導を含む病原体の適応の新しいメカニズムを強調しています.
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