地球の生態系から 巨大なファグのクラード
Basem Al-Shayeb1, Rohan Sachdeva1, Lin-Xing Chen1
1Innovative Genomics Institute, University of California Berkeley, Berkeley, CA, USA.
Nature
|February 14, 2020
まとめ
科学者は200キロ塩基以上のゲノムを持つ 何百もの巨大細菌菌を発見し 菌媒体の大きさの以前の概念に 異議を唱えました これらの巨大なファージは 拡張された遺伝的レパートリーを持ち 多様な地球規模の生態系に 広く分布しています
科学分野:
- 微生物学
- ウイルス学
- ゲノミクス
背景:
- バクテリオファージ (バクテリオファージ) は,細菌に感染し,通常は小さなゲノムを持つウイルスです.
- ファージの複製は宿主細菌に依存する.
研究 の 目的:
- 多様な生態系からの大きな細菌菌ゲノムを 配列化し特徴づけること.
- 新しく発見された巨大なファグの 遺伝的レパートリーと生物学的戦略を調査する
主な方法:
- 様々な環境サンプルから DNAの配列解析
- 35の大型ファグゲノムを手動で完成させた.
- 巨大ファグの主要なクラードを定義するための系統遺伝分析.
主要な成果:
- これまでに報告された最大の735kBのゲノムを含む200kBを超える数百のファグゲノムの発見.
- 新しいCRISPR-Casシステム,tRNA,およびタンパク質合成装置を含む拡張された遺伝的レパートリーを特定する.
- ファージはCRISPR-Casシステムを利用して宿主遺伝子発現を操作し,競合するファージを排除します.
- 巨大ファージは遺伝学的に定義され,様々な環境と宿主領域に分布しています.
結論:
- 巨大なファグの遺伝子在庫は 保存された生物学的戦略を表しています
- これらのファージは世界中に広がり 幅広い細菌宿主に感染します
- この発見はファグの多様性,進化,生態学的役割の理解を広げています
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