バクテリアの細胞形状の制御:バチルス・サブティリスの螺旋状,アクチン状のフィラメント
L J Jones1, R Carballido-López, J Errington
1Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom.
Cell
|April 6, 2001
まとめ
細菌の細胞の形状は,細胞壁だけでなく,MreBのようなタンパク質によって決定されます. これらのタンパク質は螺旋状の構造を形成し,バクテリアの形態変異におけるアクチンのような細胞骨格の役割を示唆しています.
科学分野:
- 微生物学 微生物学とは
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- 伝統的に,細菌の細胞壁は,細胞の形状を決定する唯一の要因と考えられてきました.
- バクテリアに開かれた細胞骨格の存在は,以前は確立されていなかった.
研究 の 目的:
- 細菌細胞形態変異におけるMreBおよびMblタンパク質の役割を調査する.
- MreBとMblタンパク質の細胞下部位と構造的組織を決定する.
主な方法:
- バチルス・サブティリスのmreBおよびmbl遺伝子の遺伝子解析.
- タンパク質タグと顕微鏡を用いた細胞下局所化研究.
- ユーカリオットアクトインとの比較シーケンス分析.
主要な成果:
- MreBとMblのタンパク質は,バチルス・サブティリスの細胞の形状の異なる側面に不可欠です.
- MreBとMblの両方のタンパク質は,細胞表面の近くで独特の繊維状の螺旋状の構造を形成します.
- MreBのようなタンパク質は,様々な細菌種にわたって保存されています.
結論:
- MreBのようなタンパク質は,細菌の細胞形態変異において重要な細胞骨格的役割を果たします.
- これらのタンパク質は,真核細胞のアクチン細胞骨格に類似して機能します.
- 細菌の細胞の形状は,細胞壁だけでなく,内部タンパク質の枠組みによって調節されます.
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