3AYS

GH5 endoglucanase from a ruminal fungus in complex with cellotriose

3AYS の概要

• エントリーDOI: 10.2210/pdb3ays/pdb
• 関連するPDBエントリー: 3ayr
• 関連するBIRD辞書のPRD_ID: PRD_900021
• 分子名称: Endoglucanase, beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose (3 entities in total)
• 機能のキーワード: tim barrel, hydrolase, carbohydrate/sugar binding
• 由来する生物種: Piromyces rhizinflatus
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 43823.72

構造登録者

Tseng, C.-W.,Ko, T.-P.,Guo, R.-T.,Liu, J.-R. (登録日: 2011-05-16, 公開日: 2011-11-02, 最終更新日: 2024-10-23)

主引用文献

Tseng, C.-W.,Ko, T.-P.,Guo, R.-T.,Huang, J.-W.,Wang, H.-C.,Huang, C.-H.,Cheng, Y.-S.,Wang, A.H.-J.,Liu, J.-R.
Substrate binding of a GH5 endoglucanase from the ruminal fungus Piromyces rhizinflata.
Acta Crystallogr.,Sect.F, 67:1189-1194, 2011

PubMed Abstract: The endoglucanase EglA from Piromyces rhizinflata found in cattle stomach belongs to the GH5 family of glycoside hydrolases. The crystal structure of the catalytic domain of EglA shows the (β/α)(8)-barrel fold typical of GH5 enzymes. Adjacent to the active site of EglA, a loop containing a disulfide bond not found in other similar structures may participate in substrate binding. Because the active site was blocked by the N-terminal His tag of a neighbouring protein molecule in the crystal, enzyme-substrate complexes could not be obtained by soaking but were prepared by cocrystallization. The E154A mutant structure with a cellotriose bound to the -3, -2 and -1 subsites shows an extensive hydrogen-bonding network between the enzyme and the substrate, along with a stacking interaction between Trp44 and the -3 sugar. A possible dimer was observed in the crystal structure, but retention of activity in the E242A mutant suggested that the enzyme probably does not function as a dimer in solution. On the other hand, the first 100 amino acids encoded by the original cDNA fragment are very similar to those in the last third of the (β/α)(8)-barrel fold, indicating that EglA comprises at least two catalytic domains acting in tandem.

PubMed: 22102024
DOI: 10.1107/S1744309111032428

実験手法

X-RAY DIFFRACTION (2.2 Å)