3MHY
A New PII Protein Structure
Summary for 3MHY
| Entry DOI | 10.2210/pdb3mhy/pdb |
| Descriptor | PII-like protein Pz, 1-(2-METHOXY-ETHOXY)-2-{2-[2-(2-METHOXY-ETHOXY]-ETHOXY}-ETHANE, ADENOSINE-5'-TRIPHOSPHATE, ... (7 entities in total) |
| Functional Keywords | pii protein, alpha-beta protein, homotrimer, signaling protein |
| Biological source | Azospirillum brasilense |
| Total number of polymer chains | 3 |
| Total formula weight | 39912.61 |
| Authors | Winkler, F.K.,Truan, D.,Li, X.D. (deposition date: 2010-04-09, release date: 2010-06-09, Last modification date: 2023-11-01) |
| Primary citation | Truan, D.,Huergo, L.F.,Chubatsu, L.S.,Merrick, M.,Li, X.D.,Winkler, F.K. A new P(II) protein structure identifies the 2-oxoglutarate binding site. J.Mol.Biol., 400:531-539, 2010 Cited by PubMed Abstract: P(II) proteins of bacteria, archaea, and plants regulate many facets of nitrogen metabolism. They do so by interacting with their target proteins, which can be enzymes, transcription factors, or membrane proteins. A key feature of the ability of P(II) proteins to sense cellular nitrogen status and to interact accordingly with their targets is their binding of the key metabolic intermediate 2-oxoglutarate (2-OG). However, the binding site of this ligand within P(II) proteins has been controversial. We have now solved the X-ray structure, at 1.4 A resolution, of the Azospirillum brasilense P(II) protein GlnZ complexed with MgATP and 2-OG. This structure is in excellent agreement with previous biochemical data on 2-OG binding to a variety of P(II) proteins and shows that 2-oxoglutarate binds within the cleft formed between neighboring subunits of the homotrimer. The 2-oxo acid moiety of bound 2-OG ligates the bound Mg(2+) together with three phosphate oxygens of ATP and the side chain of the T-loop residue Gln39. Our structure is in stark contrast to an earlier structure of the Methanococcus jannaschii GlnK1 protein in which the authors reported 2-OG binding to the T-loop of that P(II) protein. In the light of our new structure, three families of T-loop conformations, each associated with a distinct effector binding mode and characterized by a different interaction partner of the ammonium group of the conserved residue Lys58, emerge as a common structural basis for effector signal output by P(II) proteins. PubMed: 20493877DOI: 10.1016/j.jmb.2010.05.036 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.4 Å) |
Structure validation
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