1EXP

BETA-1,4-GLYCANASE CEX-CD

1EXP の概要

• エントリーDOI: 10.2210/pdb1exp/pdb
• 関連するBIRD辞書のPRD_ID: PRD_900050
• 分子名称: BETA-1,4-D-GLYCANASE CEX-CD, beta-D-glucopyranose-(1-4)-2-deoxy-2-fluoro-alpha-D-glucopyranose (3 entities in total)
• 機能のキーワード: cellulose degradation, hydrolase, glycosidase
• 由来する生物種: Cellulomonas fimi
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 34396.23

構造登録者

White, A.,Tull, D.,Johns, K.L.,Withers, S.G.,Rose, D.R. (登録日: 1996-01-11, 公開日: 1997-01-27, 最終更新日: 2024-11-06)

主引用文献

White, A.,Tull, D.,Johns, K.,Withers, S.G.,Rose, D.R.
Crystallographic observation of a covalent catalytic intermediate in a beta-glycosidase.
Nat.Struct.Biol., 3:149-154, 1996

PubMed Abstract: The three-dimensional structure of a catalytically competent glycosyl-enzyme intermediate of a retaining beta-1,4-glycanase has been determined at a resolution of 1.8 A by X-ray diffraction. A fluorinated slow substrate forms an alpha-D-glycopyranosyl linkage to one of the two invariant carboxylates, Glu 233, as supported in solution by 19F-NMR studies. The resulting ester linkage is coplanar with the cyclic oxygen of the proximal saccharide and is inferred to form a strong hydrogen bond with the 2-hydroxyl of that saccharide unit in natural substrates. The active-site architecture of this covalent intermediate gives insights into both the classical double-displacement catalytic mechanism and the basis for the enzyme's specificity.

PubMed: 8564541
DOI: 10.1038/nsb0296-149

実験手法

X-RAY DIFFRACTION (1.8 Å)