2CC7
Complexes of Dodecin with Flavin and Flavin-like Ligands
Summary for 2CC7
| Entry DOI | 10.2210/pdb2cc7/pdb |
| Related | 1MOG 2CC6 2CC8 2CC9 2CCB 2CCC |
| Descriptor | VNG1446H, MAGNESIUM ION, SODIUM ION, ... (7 entities in total) |
| Functional Keywords | flavoprotein |
| Biological source | HALOBACTERIUM SALINARUM |
| Total number of polymer chains | 1 |
| Total formula weight | 7911.71 |
| Authors | Grininger, M.,Zeth, K.,Oesterhelt, D. (deposition date: 2006-01-13, release date: 2006-02-01, Last modification date: 2023-12-13) |
| Primary citation | Grininger, M.,Zeth, K.,Oesterhelt, D. Dodecins: A Family of Lumichrome Binding Proteins. J.Mol.Biol., 357:842-, 2006 Cited by PubMed Abstract: Dodecin is a small dodecameric flavoprotein from Halobacterium salinarum that contains two flavins stacked between two tryptophan residues to form an aromatic tetrade. The functional properties of heterologously expressed dodecin were investigated by fluorescence spectroscopy, which allowed the determination of dissociation constants for a number of protein-ligand complexes. The values obtained were in the nanomolar to micromolar range and correlate positively with the ligand size. These data were supplemented by X-ray crystal structures of the apododecin and holocomplexes with lumichrome, lumiflavin, riboflavin and FMN at resolutions between 1.55 to 1.95 A to unravel a gating mechanism as the structural basis for the preferential binding of the small ligands lumichrome and lumiflavin. The detailed analysis of the dodecin manifold for preferential binding of lumichrome and lumiflavin provides insight on a subatom level into a protein's strategy to gain selectivity for low molecular mass compounds by steric restrictions rather than specific interactions. Investigations on the ligand composition of a wild-type dodecin crystal (1.32 A resolution) support conclusions of functional and structural investigations on heterologously expressed dodecin, and strongly suggest that lumichrome, a molecule associated with the flavin metabolism, is a ligand of dodecin in vivo. Studies on mutant protein and a Halorhodospira halophila homologue spread the idea of a lumichrome binding system as a possible "waste"-trapping device, widely distributed in prokaryotes. PubMed: 16460756DOI: 10.1016/J.JMB.2005.12.072 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.8 Å) |
Structure validation
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