Structure of PP4397 Reveals the Molecular Basis for Different c-di-GMP Binding Modes by Pilz Domain Proteins.Ko, J., Ryu, K.S., Kim, H., Shin, J.S., Lee, J.O., Cheong, C., Choi, B.S.
(2010) J.Mol.Biol. 398: 97-110
- PubMed: 20226196
- DOI: 10.1016/j.jmb.2010.03.007
- Primary Citation of Related Structures:
- PubMed Abstract:
Cyclic diguanylate (c-di-GMP) is a global regulator that modulates pathogen virulence and biofilm formation in bacteria. Although a bioinformatic study revealed that PilZ domain proteins are the long-sought c-di-GMP binding proteins, the mechanism by ...
Cyclic diguanylate (c-di-GMP) is a global regulator that modulates pathogen virulence and biofilm formation in bacteria. Although a bioinformatic study revealed that PilZ domain proteins are the long-sought c-di-GMP binding proteins, the mechanism by which c-di-GMP regulates them is uncertain. Pseudomonas putida PP4397 is one such protein that contains YcgR-N and PilZ domains and the apo-PP4397 structure was solved earlier by the Joint Center for Structural Genomics. We determined the crystal structure of holo-PP4397 and found that two intercalated c-di-GMPs fit into the junction of its YcgR-N and PilZ domains. Moreover, c-di-GMP binding induces PP4397 to undergo a dimer-to-monomer transition. Interestingly, another PilZ domain protein, VCA0042, binds to a single molecule of c-di-GMP, and both its apo and holo forms are dimeric. Mutational studies and the additional crystal structure of holo-VCA0042 (L135R) showed that the Arg122 residue of PP4397 is crucial for the recognition of two molecules of c-di-GMP. Thus, PilZ domain proteins exhibit different c-di-GMP binding stoichiometry and quaternary structure, and these differences are expected to play a role in generating diverse forms of c-di-GMP-mediated regulation.
Department of Chemistry, KAIST, Gusong-dong 373-1, Yuseong-gu, Daejeon 305-701, South Korea.