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, University of South Florida, Tampa, Florida 33620, United States of America.
bioRxiv : the preprint server for biology
|September 4, 2024
概括
信号酶SpsB对于处理YSIRK+表面蛋白质和调节黄杆菌 (Staphylococcus aureus) 酸合成至关重要. SpsB 枯竭导致细胞缺陷,突出其在细胞包膜生物发生中的作用.
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:
- 阳性细菌利用保存的YSIRK/G-S信号 (SPYSIRK+) 来定位表面蛋白质到细胞分裂隔膜.
- 已知由LtaS介导的脂铁醇酸 (LTA) 合成能够调节S. aureus*中的SPYSIRK+蛋白贩运.
- 信号酶SpsB可以切割LtaS和SPYSIRK+蛋白质,但其确切的作用尚不清楚.
研究的目的:
- 为了研究SpsB在处理葡萄球菌表面蛋白A (SpA) 与YSIRK+信号中的作用.
- 阐明SpsB活动对SpA定位,细菌细胞形态和细胞周期进展的影响.
- 确定SpsB和LtaS局部化和细菌隔膜中的功能之间的关系.
主要方法:
- 基因操纵以耗尽SpsB在金黄色.
- 使用显微镜和生物化学分析分析SPSpA处理和SpA定位.
- 在 *spsB* 枯竭菌株中评估细胞形态和细胞周期进展.
- 在细菌隔膜上SpsB和LtaS的同定位研究.
主要成果:
- SpsB对于处理葡萄球菌表面蛋白A (SpA) 的SPSpA(YSIRK+)至关重要.
- 由于SpsB的耗尽,导致SPA隔膜局部化消失,细胞形态异常,细胞循环停止,以及子细胞分离缺陷.
- SpsB局部化到隔膜,其耗尽导致LtaS局部化的改变,这表明LtaS活动的空间调节.
结论:
- 在S. aureus*中,SpsB充当一个关键的调节器,调节表面蛋白质分泌,细胞周期进展和细胞外生物发生.
- 提出了一种双机制模型,其中SpsB处理丰富的YSIRK+蛋白质,并在隔膜上空间调节LtaS.
- 这一SpsB的规定有助于有效的YSIRK+蛋白隔膜贩运和总体细菌细胞完整性.
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