细菌SEAL域经历自身蛋白质解剖,并在受调节的内膜蛋白质解剖中起作用
Anna P Brogan1, Cameron Habib1, Samuel J Hobbs1,2
1Department of Microbiology, Harvard Medical School, Boston, MA 02115.
概括
格拉姆阳性细菌使用SigI/RsgI信号来感知细胞壁损伤. RsgI的Site-1裂变通过酶独立的自身蛋白解发生,这种机制类似于真核生物机械传导.
科学领域:
- 微生物学 微生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 阳性细菌使用SigI/RsgI西格玛因子/抗西格玛因子对来感知细胞壁损伤和植物多糖.
- 在 * Bacillus subtilis * 中的 RsgI 抗西格玛因子经受调节的膜内蛋白解 (RIP) 进行信号传导.
- 与典型的RIP途径不同,RsgI的Site-1裂变是构成性的,产品仍然相关,阻碍了内膜蛋白解.
研究的目的:
- 为了识别负责RsgI分裂的构成性Site-1蛋白酶.
- 研究RsgI裂变的机制及其与机械传导的关系.
- 探索RsgI和真核SEA领域之间的结构和功能相似之处.
主要方法:
- 对RsgI外细胞质域与真核SEA域进行比较分析.
- 在*B. subtilis*和Clostridial RsgI家族成员中研究位点-1蛋白解.
- 评估RsgI自保护解中的 conformational 菌株的作用.
主要成果:
- RsgI的外细胞质域与真核生物的SEA域具有结构和功能上的相似之处.
- 在RsgI中,Site-1蛋白解是由SEA类域的酶独立自蛋白解介导的.
- 切割部位允许通过完整的β-片保留ectodomain,并且通过缓解形状应变来抑制自保护解.
结论:
- RsgI-SigI信号由机械传导驱动,涉及SEA类域的酶独立自保护解.
- RsgI裂变的机制与真核生物机械传导信号通路具有惊人的平行关系.
- 这项研究阐明了细菌中RIP通路调节的新机制,这对理解机械生物学有意义.
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