毒素遺伝子のファグ媒介による異種間移転
1Kimmel Center for Biology and Medicine, Skirball Institute for Biomolecular Medicine, New York University Medical Center, New York, NY, 10016, USA.
Science (New York, N.Y.)
|January 3, 2009
まとめ
バクテリオファージ (バクテリアを感染させるウイルス) は,バクテリアの内部だけでなく,異なるバクテリア種間の遺伝子を転送することができます. この発見は,ヒトの病原体の進化に重大な意味を持つ.
科学分野:
- 微生物学 微生物学とは
- 遺伝学 遺伝学とは
- 進化生物学の進化生物学について
背景:
- バクテリオファージは通常,特定の細菌宿主に感染し,遺伝子交換は種内移転に限られているという仮定につながります.
- 病原性島を含む移動的遺伝要素は,細菌の適応と毒性の決定的な役割を果たしています.
研究 の 目的:
- バクテリオファージによって媒介される種間遺伝子転送の可能性を調査する.
- Listeria monocytogenesにスタフィロコックスの病原性の島移転頻度を評価する.
- 病原体の進化に対するファグ媒介遺伝子交換の影響を調査する.
主な方法:
- 実験的なトランスデュークションアッセイは,スタフィロコックスのファグとListeria monocytogenesを用いて行われます.
- Staphylococcus aureusとL. monocytogenes. の間の病原性島移転頻度の定量化について
- 種間移転を観察するために,生牛乳におけるファージ療法条件のモデリング.
主要な成果:
- スタフィロコクスの病原性島と移動要素は,種の内での伝播に匹敵する,高い頻度でListeria monocytogenesに移送されます.
- スタフィロコックスのファグはL. monocytogenesを成功裏にトランスデュースしたが,プラーク形成は観察されなかった.
- S. aureusとL. monocytogenesの間の病原性島移転は,ファグ療法をシミュレートした生ミルクモデルで確認されました.
結論:
- バクテリオファージは,異なる細菌種間の広範な遺伝情報交換を容易にし,以前の仮定に異議を唱える.
- ファグによって媒介されるこの種間遺伝子転送は,ヒトの病原体を含む細菌の病原体の進化に重大な影響を及ぼします.
- この発見は,これまで認識されていたよりも,細菌の進化と適応におけるファグの役割がより広いことを示唆している.
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