4FER

Crystal structure of Bacillus Subtilis expansin (EXLX1) in complex with cellohexaose

4FER の概要

• エントリーDOI: 10.2210/pdb4fer/pdb
• 関連するPDBエントリー: 2BH0 3D30
• 関連するBIRD辞書のPRD_ID: PRD_900020
• 分子名称: Expansin-yoaJ, beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose, ACETIC ACID, ... (6 entities in total)
• 機能のキーワード: expansin, bacteria autolysis, cellulose-binding protein
• 由来する生物種: Bacillus subtilis subsp. subtilis
• 細胞内の位置: Secreted, cell wall : O34918
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 47872.05

構造登録者

Georgelis, N.,Yennawar, N.H.,Cosgrove, D.J. (登録日: 2012-05-30, 公開日: 2012-08-22, 最終更新日: 2024-02-28)

主引用文献

Georgelis, N.,Yennawar, N.H.,Cosgrove, D.J.
Structural basis for entropy-driven cellulose binding by a type-A cellulose-binding module (CBM) and bacterial expansin.
Proc.Natl.Acad.Sci.USA, 109:14830-14835, 2012

PubMed Abstract: Components of modular cellulases, type-A cellulose-binding modules (CBMs) bind to crystalline cellulose and enhance enzyme effectiveness, but structural details of the interaction are uncertain. We analyzed cellulose binding by EXLX1, a bacterial expansin with ability to loosen plant cell walls and whose domain D2 has type-A CBM characteristics. EXLX1 strongly binds to crystalline cellulose via D2, whereas its affinity for soluble cellooligosaccharides is weak. Calorimetry indicated cellulose binding was largely entropically driven. We solved the crystal structures of EXLX1 complexed with cellulose-like oligosaccharides to find that EXLX1 binds the ligands through hydrophobic interactions of three linearly arranged aromatic residues in D2. The crystal structures revealed a unique form of ligand-mediated dimerization, with the oligosaccharide sandwiched between two D2 domains in opposite polarity. This report clarifies the molecular target of expansin and the specific molecular interactions of a type-A CBM with cellulose.

PubMed: 22927418
DOI: 10.1073/pnas.1213200109

実験手法

X-RAY DIFFRACTION (2.099 Å)