ダイエットは,哺乳類の系統とヒトの間で腸内マイクロバイオームの機能の収束を促します
Brian D Muegge1, Justin Kuczynski, Dan Knights
1Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO 63108, USA.
まとめ
哺乳類の腸内微生物は,種によって同様に多様な食事に適応し,進化に影響を与えます. 微生物群の遺伝子機能は細菌の組成を予測し,宿主と微生物の共進化パターンを明らかにする.
科学分野:
- 微生物学 微生物学とは
- 進化生物学の進化生物学について
- ゲノミクスゲノミクスとは
背景:
- 哺乳類の進化と多様化は,腸内微生物群と密接に関連しています.
- 宿主-微生物の共進化を理解することは,様々な生態学的ニッチへの適応を説明するために極めて重要です.
研究 の 目的:
- 腸内微生物のコミュニティが,哺乳類の極端な食生活の変化にどのように適応するかを調査する.
- 哺乳類の系統全体で微生物の食事への適応が保たれているかどうかを判断する.
- 微生物群の遺伝子機能と細菌種の組成との関係を調査する.
主な方法:
- 糞便サンプルから微生物コミュニティのDNAのショットガン配列解析.
- バクテリアの16SリボソームRNA遺伝子の標的配列決定.
- 33種の哺乳類と18種のヒトからの糞便DNAの分析,詳細な食事記録.
主要な成果:
- 腸内微生物群の食事への適応は,異なる哺乳類の系統にわたって顕著な類似性を示しています.
- 炭水化物活性酵素やプロテアゼを含む機能的な遺伝子レパートリーは,細菌種の集合から正確に予測できます.
- 腸内微生物群の食事による適応は,哺乳類において保存されている特徴である.
結論:
- 腸内微生物群は,哺乳類の適応と進化史において重要な役割を果たしています.
- 脊椎動物の腸内微生物を特徴づけることは,超生物レベルでの宿主の進化軌跡の洞察を提供します.
- 微生物コミュニティの構造と機能は,宿主の食事と進化と密接に関連しています.
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