細菌の細胞分裂タンパク質であるFtsZは,GTPアゼである

P de Boer¹, R Crossley, L Rothfield

¹Department of Microbiology, University of Connecticut Health Center, Farmington 06030.

Nature

|September 17, 1992

まとめ

細菌の細胞分裂は,GTPを結合し,水解するFtsZタンパク質に依存する. このGTPの活動は,FtsZ環の組み立てと細菌の細胞運動に不可欠であり,子細胞の形成を可能にします.

科学分野:

バイオケミストリーバイオケミストリー
微生物学微生物学とは
細胞生物学細胞生物学

背景:

細胞分裂の最終段階であるサイトキネシスは子細胞の形成に不可欠ですが,その生化学的メカニズムは不明です.
バクテリアでは,ftsZ遺伝子がコードするFtsZタンパク質は,細胞分裂と細胞運動の重要な役割を果たします.
FtsZ濃度は分裂周波数を調節し,分裂阻害剤の標的であることが知られている.

研究の目的:

細胞運動における細菌のFtsZタンパク質の生化学的機能を調査する.
FtsZがグアノシン三リン酸 (GTP) と相互作用し,この相互作用がその役割に不可欠であるかどうかを判断する.

主な方法:

FtsZとGTPの相互作用を研究するために,生化学的試験が使用されました.
この研究では,FtsZによるGTP結合と水解を,様々な濃度で分析した.

主要な成果:

FtsZは,GTPを特異的に結合し,水解することが判明しました.
この反応は,GTPに依存した活性化と,GDPへのGTP水解という2段階で行われます.
FtsZ濃度は,GTP依存の活性化段階に大きな影響を与える.

結論:

FtsZによるGTP結合と水解は,細菌の細胞動性において不可欠である.
これらの生化学的活動は,FtsZ環の組立を促進し,または分裂過程の重要なステップを触媒化する可能性があります.

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