Summary for 1IGV
Entry DOI | 10.2210/pdb1igv/pdb |
Related | 1IG5 1clb 3icb 4icb |
Descriptor | VITAMIN D-DEPENDENT CALCIUM-BINDING PROTEIN, INTESTINAL, MANGANESE (II) ION (3 entities in total) |
Functional Keywords | calcium-binding protein, ef-hand, manganese binding, metal binding protein |
Biological source | Bos taurus (cattle) |
Total number of polymer chains | 1 |
Total formula weight | 8565.49 |
Authors | Andersson, E.M. (deposition date: 2001-04-18, release date: 2001-04-25, Last modification date: 2024-02-07) |
Primary citation | Andersson, M.,Malmendal, A.,Linse, S.,Ivarsson, I.,Forsen, S.,Svensson, L.A. Structural basis for the negative allostery between Ca(2+)- and Mg(2+)-binding in the intracellular Ca(2+)-receptor calbindin D9k. Protein Sci., 6:1139-1147, 1997 Cited by PubMed Abstract: The three-dimensional structures of the magnesium- and manganese-bound forms of calbindin D9k were determined to 1.6 A and 1.9 A resolution, respectively, using X-ray crystallography. These two structures are nearly identical but deviate significantly from both the calcium bound form and the metal ion-free (apo) form. The largest structural differences are seen in the C-terminal EF-hand, and involve changes in both metal ion coordination and helix packing. The N-terminal calcium binding site is not occupied by any metal ion in the magnesium and manganese structures, and shows little structural deviation from the apo and calcium bound forms. 1H-NMR and UV spectroscopic studies at physiological ion concentrations show that the C-terminal site of the protein is significantly populated by magnesium at resting cell calcium levels, and that there is a negative allosteric interaction between magnesium and calcium binding. Calcium binding was found to occur with positive cooperativity at physiological magnesium concentration. PubMed: 9194174PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (1.85 Å) |
Structure validation
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