基质控制多元化和激活 VII 型分泌的多域 ATPase 电机
Oren S Rosenberg1, Dustin Dovala2, Xueming Li3
1Division of Infectious Diseases, Department of Medicine, UCSF Medical Center, University of California, San Francisco, San Francisco, CA 94143-0654, USA.
Cell
|April 14, 2015
概括
第七类蛋白质分泌 (T7S) 系统需要所有基质才能发挥作用. 基质EsxB结合激活了转位酶EccC,通过刺激多元化,而不是全osterically.
科学领域:
- 微生物学 微生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 第七类蛋白质分泌 (T7S) 对于 Mycobacterium tuberculosis 和 Staphylococcus aureus 等细菌的毒性至关重要.
- 独特的是,T7S系统需要所有分泌基质都活跃,这表明了复杂的调节机制.
研究的目的:
- 使用结构生物学阐明T7S转位酶EccC及其基质EsxB的功能.
- 了解T7S中基质相互依赖的机制.
主要方法:
- 使用X射线晶体学来确定EccC转位酶的结构.
- 为了研究EccC和EsxB之间的相互作用,进行了生物化学测试.
主要成果:
- EccC的晶体结构揭示了其三个调节酶活性的ATPase域之间的相互作用.
- EsxB与EccC的C端ATPase域结合,增加其活性.
- 基质结合通过多元化激活了EccC,而不是全调节.
结论:
- EsxB基板是T7S机械的组成部分,解释了基板的相互依赖性.
- 提出了一个模型,其中基质结合调节了它们从细菌中协调释放的模式.
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