信号酶SpsB协调葡萄球菌细胞周期,表面蛋白质隔膜贩运和LTA合成
Ran Zhang1, Yaosheng Jia1, Salvatore J Scaffidi1
1Department of Molecular Biosciences, College of Arts and Sciences; Center for Antimicrobial Resistance, University of South Florida, Tampa, Florida, USA.
mBio
|January 24, 2025
概括
信号酶SpsB对格拉姆阳性细菌至关重要,通过控制YSIRK+蛋白和隔膜LtaS定位来调节细胞分裂和蛋白质分泌. 这一发现为细菌细胞外生物发生提供了新的见解.
科学领域:
- 微生物学 微生物学
- 细胞生物学 细胞生物学
- 细菌病原体的产生
背景情况:
- 阳性细菌利用细胞壁的表面蛋白质与YSIRK/G-S信号 (SPYSIRK+) 进行致病.
- 这些蛋白质运输到细胞分裂隔膜,但机制仍然不清楚.
- 由LtaS介导的脂铁醇酸 (LTA) 合成已被证明可以限制SPYSIRK+蛋白质隔膜贩运.
研究的目的:
- 阐明信号酶SpsB在黄金葡萄球菌中SPYSIRK+蛋白的隔膜贩运中的作用.
- 调查SpsB在协调LtaS介导的LTA生产和细菌细胞周期调节中的功能.
- 探索这些机制在格拉姆阳性细菌中的潜在保护.
主要方法:
- *spsB*的遗传耗尽和SPSpA(YSIRK+)处理和定位的分析.
- SPSpA的位点导向突变发生,以破坏SpsB裂变 (A37P突变).
- 使用显微镜进行细胞形态和局部化研究,以评估SpsB和LtaS分布.
主要成果:
- SpsB对于处理SPSpA(YSIRK+)及其适当的隔膜局部化至关重要;防止裂变的突变取消了局部化.
- 耗尽*spsB*会导致异常细胞形态,细胞循环停止和子细胞分离受损.
- SpsB 位于隔膜上,并且在空间上调节 LtaS,而 *spsB* 耗尽导致 LtaS 隔膜丰富.
结论:
- 通过直接处理和空间调节LtaS,SpsB作为YSIRK+蛋白隔膜贩运的关键调节者.
- SpsB扮演着双重的角色:处理分泌的蛋白质和协调细胞外生物发生与细胞分裂.
- 鉴定出的机制突出显示了SpsB在调控蛋白质分泌,细胞循环和细胞包膜生物发生方面的新功能,这可能适用于其他格拉姆阳性细菌.
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