核状のサイズスケーリングと細菌間の細胞内翻訳機構
William T Gray1, Sander K Govers2, Yingjie Xiang3
1Microbial Sciences Institute, Yale University, West Haven, CT, USA; Department of Pharmacology, Yale University, New Haven, CT, USA.
Cell
|June 1, 2019
まとめ
細菌のヌクレオイドの大きさは細胞の大きさで,真核細胞の臓器に似ています. DNA量に関係なく この関係は 細菌の細胞組織と生体物理学の 新しい洞察を明らかにします
科学分野:
- 細胞生物学
- 微生物学
- バイオ物理学
背景:
- 細胞の大きさに比例するオルガネルは ユカリオットの現象として知られている.
- 膜がないバクテリアのヌクレオイドは,同様のスケーリングを示すことが予想されませんでした.
- 細菌の細胞内組織を理解することは 細胞生物学にとって極めて重要です
研究 の 目的:
- バクテリアのヌクレオイドのサイズが 細胞のサイズに比例するかどうかを調べるため
- バクテリアのヌクレオイドサイズ,細胞サイズ,DNA含有量との関係を決定する.
- 細菌の細胞特性に対する核細胞質比の影響を調査する.
主な方法:
- 異なる細菌種におけるヌクレオイドと細胞の大きさの比較分析.
- 栄養条件とDNA含有量を変化させる 制御された実験
- リボソームの移動性を含む細胞質の生物物理的性質の評価
主要な成果:
- DNA量に関係なく,細菌のヌクレオイドサイズと細胞サイズとの強い相関が観察されました.
- 種内ではほぼ恒常的な核細胞対細胞サイズ比が発見され,種によって異なる.
- 核サイトプラズマ比の差異は,異なるサイトプラズマの生体物理的性質とリボソームの行動と相関する.
結論:
- バクテリアのヌクレオイドの大きさは,細胞の大きさとのスケール関係を示し,以前の仮定に異議を唱える.
- 細菌における核細胞質比は,集団細胞のサイズと関連しており,細胞内組織に影響する.
- これらの発見は 細菌細胞の基本的組織原理と 生物物理学的特徴を明らかにしています
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