一种类型VII分泌的脂酶毒素,具有反向域排列
Stephen R Garrett1, Nicole Mietrach1, Justin Deme2
1Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
Nature communications
|December 19, 2023
概括
研究人员发现了一种新的细菌分泌系统基质,TslA,具有逆转的域结构. 这一发现表明,VII型蛋白质分泌系统 (T7SS) 可以识别基质蛋白的两端的分泌信号.
科学领域:
- 微生物学 微生物学
- 细菌病原体的产生
- 蛋白质分泌 蛋白质分泌
背景情况:
- 第七类蛋白质分泌系统 (T7SS) 对于许多格拉姆阳性细菌和病原菌菌的毒性至关重要.
- T7SS基板通常具有N端螺旋域用于准,具有多种C端功能域.
- 规范T7SS基板利用N端信号序列进行分泌.
研究的目的:
- 描述一种具有反向域组织的新型T7SS基质类.
- 为了研究斯塔菲洛科克黄金菌中TslA蛋白的分泌机制和功能.
- 为了确定T7SS基质识别的结构基础.
主要方法:
- 细菌遗传学和蛋白质生物化学技术.
- 电子显微镜 (Cryo-EM) 用于结构分析.
- 酶活性测试以确定脂酶A的功能.
主要成果:
- 确定了TslA作为一个T7SS基质,具有逆转的N终端脂酶A域和抗葡萄球菌活性.
- 证明TslaA分泌需要伴侣蛋白TlaA1和TlaA2,它们与C端域相互作用.
- 冷电磁探测揭示了 TslA 复合物和正规的 T7SS 基质之间的结构相似性.
结论:
- T7SS可以分泌在N端或C端的信号序列的基质.
- TslA代表了一类新的T7SS基质,扩大了我们对细菌分泌的理解.
- 这些发现表明T7SS基质识别和准机制的灵活性.
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