バクテリアの化学受容体によるトランスメブランシグナル伝達: E. coli トランスデューサは,出力シグナルがロックされている

P Ames¹, J S Parkinson

¹Biology Department, University of Utah, Salt Lake City 84112.

Cell

|December 2, 1988

まとめ

E. coli の変異性メチル受容性化学反応タンパク質 (MCP) は,刺激なしに信号を生成し,これらの細菌のセンサーがフラゲラモーターを制御し,環境に適応する方法を明らかにします.

科学分野:

微生物学微生物学とは
分子生物学は分子生物学である.
バイオケミストリーバイオケミストリー

背景:

メチル受容性化学反応タンパク質 (MCP) は,細菌化学反応における重要な膜伝達シグナルである.
これらの受容体は,フラゲラ運動活動を調節することによって,環境刺激に対する反応を媒介する.

研究の目的:

E. coli Tsr タンパク質変異体の特徴づけによって,MCP のシグナル伝達機構を調査する.
MCP信号生成と感覚適応の構造的基礎を理解する.

主な方法:

構成信号を発揮するE. coli Tsr変異体の分離と特徴付け.
変異フェノタイプの分析,信号出力および適応特性を含む.

主要な成果:

構成的に信号を発し,感覚適応に欠陥がある"ロックされた" Tsr ミュータントが特定されました.
MCPが積極的にシグナルを生成し,時計回りの方向と逆の方向の両方でフラジェラモーターの回転に影響を及ぼすことを実証しました.
様々な領域 (メチル化部位,膜を横断するセグメント,リンカー領域) の変化が,MCPのシグナル状態移行に影響することを示した.

結論:

MCPシグナル伝達には,受容体分子自身による積極的な信号生成が含まれています.
MCPにおけるトランスメブランシグナル伝達は,ペリプラズマ領域とサイトプラズマ領域の間の構造変化の直接的な伝播によって起こる可能性が高い.
これらの発見は,細菌の化学作用と信号伝導の基礎となる分子機構の洞察を提供します.

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