Molière Noël, Hoßmann Jörn, Schäfer Heinrich, Turgay Kürşad
Naturwissenschaftliche Fakultät, Institut für Mikrobiologie, Leibniz Universität HannoverHannover, Germany; Institut für Biologie-Mikrobiologie, Freie Universität BerlinBerlin, Germany.
Institut für Biologie-Mikrobiologie, Freie Universität Berlin Berlin, Germany.
Front Microbiol. 2016 Mar 16;7:315. doi: 10.3389/fmicb.2016.00315. eCollection 2016.
The Hsp100/Clp protease complexes of Bacillus subtilis ClpXP and ClpCP are involved in the control of many interconnected developmental and stress response regulatory networks, including competence, redox stress response, and motility. Here we analyzed the role of regulatory proteolysis by ClpXP and ClpCP in motility development. We have demonstrated that ClpXP acts on the regulation of motility by controlling the levels of the oxidative and heat stress regulator Spx. We obtained evidence that upon oxidative stress Spx not only induces the thiol stress response, but also transiently represses the transcription of flagellar genes. Furthermore, we observed that in addition to the known impact of ClpCP via the ComK/FlgM-dependent pathway, ClpCP also affects flagellar gene expression via modulating the activity and levels of the global regulator DegU-P. This adds another layer to the intricate involvement of Clp mediated regulatory proteolysis in different gene expression programs, which may allow to integrate and coordinate different signals for a better-adjusted response to the changing environment of B. subtilis cells.
枯草芽孢杆菌的Hsp100/Clp蛋白酶复合物ClpXP和ClpCP参与控制许多相互关联的发育和应激反应调节网络，包括感受态、氧化还原应激反应和运动性。在此，我们分析了ClpXP和ClpCP介导的调节性蛋白水解在运动性发育中的作用。我们证明，ClpXP通过控制氧化和热应激调节因子Spx的水平来调节运动性。我们获得的证据表明，在氧化应激下，Spx不仅诱导硫醇应激反应，还短暂抑制鞭毛基因的转录。此外，我们观察到，除了ClpCP通过ComK/FlgM依赖途径产生的已知影响外，ClpCP还通过调节全局调节因子DegU-P的活性和水平来影响鞭毛基因的表达。这为Clp介导的调节性蛋白水解在不同基因表达程序中的复杂参与增加了另一层面，这可能允许整合和协调不同信号，以便更好地适应枯草芽孢杆菌细胞不断变化的环境。
