移動性遺伝子要素の急速な進化は,細菌のファグに対する耐性を誘発する

Fatima Aysha Hussain¹, Javier Dubert^1,2, Joseph Elsherbini¹

¹Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.

Science (New York, N.Y.)

|October 21, 2021

まとめ

海洋ビブリオ菌は大きく多様な移動性遺伝子要素を通して菌媒体の耐性を進化させる. これらの要素は急速に変化し蓄積的な保護と実験室での研究では見られなかった進化の別の経路を提供します

科学分野:

微生物の進化
バクテリオファージとバクテリアの相互作用
海の微生物学

背景:

バクテリオファージはバクテリアの進化の原動力として知られています.
バクテリアの進化の理解は限られています
海のビブリオの進化動態は,ファグの圧力下では十分に理解されていません.

研究の目的:

海のビブリオのファグ耐性のメカニズムを調査する.
ファージの防御を媒介する遺伝的要素を特徴づける.
自然集団におけるこれらの防御要素の進化的転移を調査する.

主な方法:

海洋ビブリオ菌株の比較ゲノミクス
ファージ防御に関連する移動性遺伝子の分析
防衛要素の転用率の進化論的分析

主要な成果:

海のビブリオのファージ感受性は,大きく多様な移動性遺伝子要素によって制御されます.
これらの防御要素は,ファージ受容体から独立して,急速な進化的転移を示します.
保護は累積的なもので,単一のゲノムには複数の防御要素 (6-12個) が含まれており,柔軟なゲノムの90%以上を占める.
急速なターンオーバーはファグの耐性を他のゲノム特性から切り離す.

結論:

野生の海洋ビブリオのファグ耐性は,急速に進化する移動性遺伝要素によって媒介されます.
この急速な転機は実験室の予測とは異なる進化の軌道をたどるのです
移動性遺伝子要素は,海洋環境におけるファグの捕食に対する細菌の適応を形作る上で重要な役割を果たします.

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