Structural basis for diguanylate cyclase activation by its binding partner in Pseudomonas aeruginosa
Gukui Chen,
Jiashen Zhou,
Yili Zuo,
Weiping Huo,
Juan Peng,
Meng Li,
Yani Zhang,
Tietao Wang,
Lin Zhang,
Liang Zhang,
Haihua Liang
Affiliations
Gukui Chen
Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, ShaanXi, China
Jiashen Zhou
Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
Yili Zuo
Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, ShaanXi, China
Weiping Huo
Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, ShaanXi, China
Juan Peng
Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, ShaanXi, China
Meng Li
Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, ShaanXi, China
Yani Zhang
Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, ShaanXi, China
Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, ShaanXi, China
Lin Zhang
Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, ShaanXi, China; School of Medicine, Southern University of Science and Technology, Shenzhen, China
Cyclic-di-guanosine monophosphate (c-di-GMP) is an important effector associated with acute-chronic infection transition in Pseudomonas aeruginosa. Previously, we reported a signaling network SiaABCD, which regulates biofilm formation by modulating c-di-GMP level. However, the mechanism for SiaD activation by SiaC remains elusive. Here we determine the crystal structure of SiaC-SiaD-GpCpp complex and revealed a unique mirror symmetric conformation: two SiaD form a dimer with long stalk domains, while four SiaC bind to the conserved motifs on the stalks of SiaD and stabilize the conformation for further enzymatic catalysis. Furthermore, SiaD alone exhibits an inactive pentamer conformation in solution, demonstrating that SiaC activates SiaD through a dynamic mechanism of promoting the formation of active SiaD dimers. Mutagenesis assay confirmed that the stalks of SiaD are necessary for its activation. Together, we reveal a novel mechanism for DGC activation, which clarifies the regulatory networks of c-di-GMP signaling.
