title: Crystal structure of an EAL domain in complex with reaction product 5'-pGpG.
abstract: FimX is a large multidomain protein containing an EAL domain and involved in twitching motility in Pseudomonas aeruginosa. We present here two crystallographic structures of the EAL domain of FimX (residues 438-686): one of the apo form and the other of a complex with 5'-pGpG, the reaction product of the hydrolysis of c-di-GMP. In both crystal forms, the EAL domains form a dimer delimiting a large cavity encompassing the catalytic pockets. The ligand is trapped in this cavity by its sugar phosphate moiety. We confirmed by NMR that the guanine bases are not involved in the interaction in solution. We solved here the first structure of an EAL domain bound to the reaction product 5'-pGpG. Though isolated FimX EAL domain has a very low catalytic activity, which would not be significant compared to other catalytic EAL domains, the structure with the product of the reaction can provides some hints in the mechanism of hydrolysis of the c-di-GMP by EAL domains.
authors.affiliation: Laboratoire de Cristallographie et RMN biologiques, UMR 8015-Cente National de la Recherche Scientifique, Paris, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Robert-Paganin
authors.forename: Sylvie
authors.initials: S
authors.lastname: Nonin-Lecomte
authors.forename: Stéphane
authors.initials: S
authors.lastname: Réty
mesh_terms: D000595:Amino Acid Sequence; D001059:Apoproteins / Q000737:chemistry / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D020134:Catalytic Domain; D018360:Crystallography, X-Ray; D006152:Cyclic GMP / Q000031:analogs & derivatives / Q000378:metabolism; D003848:Deoxyguanine Nucleotides / Q000378:metabolism*; D006868:Hydrolysis; D008024:Ligands; D008274:Magnesium / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009596:Nitrophenols / Q000378:metabolism; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D011485:Protein Binding; D055503:Protein Multimerization; D017434:Protein Structure, Tertiary; D011550:Pseudomonas aeruginosa / Q000201:enzymology*; D016415:Sequence Alignment; D012996:Solutions
chemical_list: D001059:Apoproteins; D001426:Bacterial Proteins; D003848:Deoxyguanine Nucleotides; D008024:Ligands; D009596:Nitrophenols; D012996:Solutions; C034299:deoxydiguanosine diphosphosphate; C062025:bis(3',5')-cyclic diguanylic acid; C002887:bis(4-nitrophenyl)phosphate; D010727:Phosphoric Diester Hydrolases; D006152:Cyclic GMP; D008274:Magnesium