エクスポートされたペプチドは,B. subtilisの細胞密度シグナル伝達に貢献するために細胞内機能します
B A Lazazzera1, J M Solomon, A D Grossman
1Department of Biology, Massachusetts Institute of Technology, Cambridge 02139, USA.
Cell
|June 13, 1997
まとめ
シグナリングペプチドPhrAとCSFは,バチルス・サブティリスの能力と胞子形成を調節する. 機能的研究により,これらのペプチドは細胞輸入を必要とし,CSFはオリゴペプチド浸透酵素 (Opp) トランスポーターを利用することが明らかになった.
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:
- バクテリアの能力と分泌は,Bacillus subtilis.の重要な発達経路である.
- これらのプロセスは,高細胞密度の成長中に蓄積される細胞外シグナル伝達ペプチドによって調節されます.
- これらのペプチド媒介信号を理解することは,バクテリアの発達制御を解読する鍵です.
研究 の 目的:
- B. subtilis. のPhrAおよびCSFシグナルペプチドの機能と輸送を調査する.
- 成熟したシグナル伝達ペプチドが細胞内で機能し,輸入を必要とするかどうかを判断する.
- CSF輸送のメカニズムとその集中に依存する活動を解明する.
主な方法:
- 成熟したPhrAとCSFペプチドを細胞内に発現させるための遺伝子構築.
- 能力開発とスポーツのフェノタイプ分析.
- オリゴペプチド浸透性 (Opp) 輸送アッセイは,生理学的濃度でCSFを使用しています.
- 遺伝子発現に関するCSFの活動に関する用量反応分析.
主要な成果:
- 発現した成熟ペンタペプチド (PhrAとCSF) は細胞内機能しており,輸入の必要性を示唆しています.
- CSFは,オリゴペプチド浸透酵素 (Opp) によって10 nMでB. subtilis細胞に輸送されました.
- CSFは,低濃度では能力を刺激し,高濃度では運動を刺激しながら能力を抑制する.
結論:
- B. subtilisのシグナリングペプチドであるPhrAとCSFは,その機能を果たすために細胞からの輸入を必要とします.
- オリゴペプチド浸透酵素 (Opp) システムは,CSFを細胞に輸送する責任を負う.
- CSFは,B. subtilisの発達において,複雑で,濃度に依存する規制的な役割を果たし,能力とスポルレーションの両方に影響を及ぼします.
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