3RDU
Crystal structure of R7-2 streptavidin complexed with PEG
Summary for 3RDU
Entry DOI | 10.2210/pdb3rdu/pdb |
Related | 3RDM 3RDO 3RDQ 3RDS 3RDX 3RE5 3RE6 |
Descriptor | Streptavidin, GLYCEROL, PENTAETHYLENE GLYCOL, ... (4 entities in total) |
Functional Keywords | streptavidin variants, improved desthiobiotin binding, opened loop destabilization, biotin binding protein |
Biological source | Streptomyces avidinii |
Cellular location | Secreted: P22629 |
Total number of polymer chains | 1 |
Total formula weight | 16480.94 |
Authors | Malashkevich, V.N.,Magalhaes, M.,Czecster, C.M.,Guan, R.,Levy, M.,Almo, S.C. (deposition date: 2011-04-01, release date: 2011-07-06, Last modification date: 2023-09-13) |
Primary citation | Magalhaes, M.L.,Czekster, C.M.,Guan, R.,Malashkevich, V.N.,Almo, S.C.,Levy, M. Evolved streptavidin mutants reveal key role of loop residue in high-affinity binding. Protein Sci., 20:1145-1154, 2011 Cited by PubMed Abstract: We have performed a detailed analysis of streptavidin variants with altered specificity towards desthiobiotin. In addition to changes in key residues which widen the ligand binding pocket and accommodate the more structurally flexible desthiobiotin, the data revealed the role of a key, non-active site mutation at the base of the flexible loop (S52G) which slows dissociation of this ligand by approximately sevenfold. Our data suggest that this mutation results in the loss of a stabilizing contact which keeps this loop open and accessible in the absence of ligand. When this mutation was introduced into the wild-type protein, destabilization of the opened loop conferred a ∼10-fold decrease in both the on-rate and off-rate for the ligand biotin-4-fluoroscein. A similar effect was observed when this mutation was added to a monomeric form of this protein. Our results provide key insight into the role of the streptavidin flexible loop in ligand binding and maintaining high affinity interactions. PubMed: 21520321DOI: 10.1002/pro.642 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (1.5 Å) |
Structure validation
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