4OMX

Crystal structure of goat beta-lactoglobulin (trigonal form)

4OMX の概要

• エントリーDOI: 10.2210/pdb4omx/pdb
• 関連するPDBエントリー: 4OMW
• 分子名称: beta-lactoglobulin, SULFATE ION, UREA, ... (5 entities in total)
• 機能のキーワード: lipocalin, transport, transport protein
• 由来する生物種: Capra hircus (domestic goat, goats)
• 細胞内の位置: Secreted: P02756
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 18674.56

構造登録者

Loch, J.I.,Swiatek, S.,Czub, M.,Ludwikowska, M.,Lewinski, K. (登録日: 2014-01-27, 公開日: 2014-11-19, 最終更新日: 2024-10-30)

主引用文献

Loch, J.I.,Bonarek, P.,Polit, A.,Swiatek, S.,Czub, M.,Ludwikowska, M.,Lewinski, K.
Conformational variability of goat beta-lactoglobulin: Crystallographic and thermodynamic studies.
Int.J.Biol.Macromol., 72C:1283-1291, 2014

PubMed Abstract: Goat β-lactoglobulin (GLG), lipocalin protein sharing high sequence similarity to bovine β-lactoglobulin (BLG), has been structurally and thermodynamically characterized. Two crystal forms of GLG have been obtained, trigonal (P3121) and orthorhombic (P21212), with unique molecular packing, not observed previously for BLG. In the trigonal structure, GLG molecules have EF-loop in closed conformation while in the orthorhombic structure, for the first time, symmetric and asymmetric dimers of β-lactoglobulin are observed simultaneously. It indicates that the opening or closing EF-loop does not occur in both subunits at the same time but might be sequential and cooperative. Comparison of GLG and BLG structures revealed presence of various conformers of EF and GH. ITC studies showed that at pH 7.5 GLG binds sodium dodecyl sulfate with Gibbs energy similar to BLG, however, with different contribution from enthalpic and entropic component. At pH 7.5 GLG forms dimers with dimerization constant Ka = 34.28 × 10(3) M(-1), significantly higher than observed for BLG. Similar mechanism of conformational changes and ligand binding indicates that GLG and BLG may play analogous biological role.

PubMed: 25450833
DOI: 10.1016/j.ijbiomac.2014.10.031

実験手法

X-RAY DIFFRACTION (2.3 Å)