3RDM

Crystal structure of R7-2 streptavidin complexed with biotin/PEG

3RDM の概要

• エントリーDOI: 10.2210/pdb3rdm/pdb
• 関連するPDBエントリー: 3RDO 3RDQ 3RDS 3RDU 3RDX 3RE5 3RE6
• 分子名称: Streptavidin, PENTAETHYLENE GLYCOL, BIOTIN, ... (4 entities in total)
• 機能のキーワード: streptavidin variants, improved desthiobiotin binding, opened loop destabilization, biotin binding protein
• 由来する生物種: Streptomyces avidinii
• 細胞内の位置: Secreted: P22629
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 16448.97

構造登録者

Malashkevich, V.N.,Magalhaes, M.,Czecster, C.M.,Guan, R.,Levy, M.,Almo, S.C. (登録日: 2011-04-01, 公開日: 2011-07-06, 最終更新日: 2023-09-13)

主引用文献

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

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: 21520321
DOI: 10.1002/pro.642

実験手法

X-RAY DIFFRACTION (1.6 Å)