He Meina, Tao Yongxin, Mu Kexin, Feng Haoqi, Fan Ying, Liu Tong, Huang Qiaoyun, Xiao Yujie, Chen Wenli
National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.
Elife. 2025 Apr 8;13:RP100914. doi: 10.7554/eLife.100914.
Copper is an essential enzyme cofactor in bacteria, but excess copper is highly toxic. Bacteria can cope with copper stress by increasing copper resistance and initiating chemorepellent response. However, it remains unclear how bacteria coordinate chemotaxis and resistance to copper. By screening proteins that interacted with the chemotaxis kinase CheA, we identified a copper-binding repressor CsoR that interacted with CheA in . CsoR interacted with the HPT (P1), Dimer (P3), and HATPase_c (P4) domains of CheA and inhibited CheA autophosphorylation, resulting in decreased chemotaxis. The copper-binding of CsoR weakened its interaction with CheA, which relieved the inhibition of chemotaxis by CsoR. In addition, CsoR bound to the promoter of copper-resistance genes to inhibit gene expression, and copper-binding released CsoR from the promoter, leading to increased gene expression and copper resistance. cells exhibited a chemorepellent response to copper in a CheA-dependent manner, and CsoR inhibited the chemorepellent response to copper. Besides, the CheA-CsoR interaction also existed in proteins from several other bacterial species. Our results revealed a mechanism by which bacteria coordinately regulated chemotaxis and resistance to copper by CsoR.
铜是细菌中一种必需的酶辅因子，但过量的铜具有高毒性。细菌可以通过增强铜抗性和启动化学排斥反应来应对铜胁迫。然而，细菌如何协调趋化作用和对铜的抗性仍不清楚。通过筛选与趋化激酶CheA相互作用的蛋白质，我们鉴定出一种在[具体环境未提及]中与CheA相互作用的铜结合阻遏物CsoR。CsoR与CheA的HPT（P1）、二聚体（P3）和HATPase_c（P4）结构域相互作用，并抑制CheA自身磷酸化，导致趋化作用减弱。CsoR的铜结合削弱了其与CheA的相互作用，从而解除了CsoR对趋化作用的抑制。此外，CsoR与铜抗性基因的启动子结合以抑制基因表达，而铜结合使CsoR从启动子上释放，导致基因表达增加和铜抗性增强。[具体细胞未提及]细胞以CheA依赖的方式对铜表现出化学排斥反应，并且CsoR抑制对铜的化学排斥反应。此外，CheA-CsoR相互作用也存在于其他几种细菌物种的蛋白质中。我们的结果揭示了一种细菌通过CsoR协调调节趋化作用和对铜抗性的机制。
