Structural insights into the functional role of GMP in modulating the YfiBNR system
Structural insights into the functional role of GMP in modulating the YfiBNR system
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GMP 在调节 YfiBNR 系统中的功能作用的结构见解
DOI：
10.1016/j.bbrc.2017.08.139
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发表时间：
2017
影响因子：
3.1
通讯作者：
Jiang Tao
中科院分区：
文献类型：
--
作者：
Zhou Lei;Xu Min;Jiang Tao
YfiBNR是一种三联环-二-GMP（c-di-GMP）信号系统，在革兰氏阴性菌铜绿假单胞菌的生物膜形成中起重要作用，其调节与慢性肺部感染和耐药性强烈相关的细胞过程。外膜脂蛋白YfiB可以通过隔离周质蛋白YfiR来释放对内膜蛋白YfiN的抑制，导致YfiN的二鸟苷酸环化酶活性的激活和c-di-GMP的产生。与对c-di-GMP的广泛研究相反，对GMP在YfiBNR系统中的作用知之甚少。在这里，我们报告了与GMP复合的YfiR和与GMP复合的YfiBL 43 P-YfiR的晶体结构。在YfiR-GMP复合物中，GMP位于由R175/H177/R60形成的亲水口袋中，而在YfiBL 43 P-YfiR-GMP复合物中，GMP位于稍微分开的亲水口袋中，GMP与YfiB和YfiR两者形成氢键。结合亲和力试验和生物膜形成试验表明，GMP可以通过促进YfiB和YfiR的亲和力来激活二鸟苷酸环化酶活性以促进生物膜的产生。因此，这一发现为预防生物膜相关的抗生素耐药性和慢性感染提供了新的视角。
YfiBNR, a tripartite cyclic-di-GMP (c-di-GMP) signalling system, plays an important role in biofilm formation of the gram-negative bacteriumP. aeruginosa, which regulates the cellular processes strongly associated with chronic lung infections and drug resistance. The outer-membrane lipoprotein YfiB can release the inhibition of the inner membrane protein YfiN by sequestering the periplasmatic protein YfiR, resulting in the activation of diguanylate cyclase activity of YfiN and the production of c-di-GMP. In contrast to the extensive studies on c-di-GMP, little is known about how GMP acts in the YfiBNR system. Here, we report the crystal structures of YfiR complexed with GMP and YfiBL43P-YfiR complexed with GMP. In the YfiR-GMP complex, GMP is located in a hydrophilic pocket formed by R175/H177/R60, while in the YfiBL43P-YfiR-GMP complex, GMP is located in a slightly separated hydrophilic pocket, with GMP forming hydrogen bonds with both YfiB and YfiR. A binding affinity test and biofilm formation assay indicated that GMP may activate diguanylate cyclase activity to promote biofilm production by promoting the affinity of YfiB and YfiR. This finding thus provides a new perspective for preventing biofilm-related antibiotic resistance and chronic infections.