メタボリックに活性な膜に結合した臓器に含まれるDNAを持つ"センチメートルの長さの細菌
Jean-Marie Volland1,2, Silvina Gonzalez-Rizzo3, Olivier Gros3,4
1Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
まとめ
巨大バクテリアのCandidatus Thiomargarita magnificaは 細菌の細胞サイズに挑戦しています 肉眼で見えるこの細菌は 極端な複合体と 独特の細胞組織を示し 細菌の複雑性を再定義しています
科学分野:
- 微生物学
- 細胞生物学
- ゲノミクス
背景:
- 細菌の細胞は通常2ミクロメートルで 極端な例では750ミクロメートルに達します
- 細菌の細胞サイズに関する理論的限界はよく確立されています.
研究 の 目的:
- 異常に大きな細菌の形状,ゲノム,生命周期を特徴付ける.
- 細菌の細胞の大きさを 調べるためだ
主な方法:
- 光顕微鏡
- X線顕微鏡
- 電子顕微鏡
- ゲノムシーケンシング
主要な成果:
- 特徴的なCandidatus Thiomargarita magnificaは 平均9000ミクロメートルの長さで 肉眼で見えます
- 前例のない複合性 (50万個以上のゲノムコピー) と大きなゲノムが観察されました.
- 不対称な染色体分離を記録した
- 膜に結合した臓器細胞内の遺伝物質とリボソームの区分を特定した.
結論:
- Candidatus Thiomargarita magnificaは 理論上の細菌の細胞サイズ制限を数桁上回っています
- 細菌は複雑さを増し 細菌細胞の伝統的な定義に 異議を唱えるようになりました
- 独特の特徴は 細菌の細胞発達の新たな進化の経路を示唆している.
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