4C4C

Michaelis complex of Hypocrea jecorina CEL7A E217Q mutant with cellononaose spanning the active site

4C4C の概要

• エントリーDOI: 10.2210/pdb4c4c/pdb
• 関連するPDBエントリー: 4C4D
• 分子名称: CELLULOSE 1,4-BETA-CELLOBIOSIDASE, 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-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose, COBALT (II) ION, ... (6 entities in total)
• 機能のキーワード: hydrolase, glycoside hydrolase, cellulase.
• 由来する生物種: TRICHODERMA REESEI
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 48482.61

構造登録者

Haddad-Momeni, M.,Sandgren, M.,Stahlberg, J. (登録日: 2013-09-05, 公開日: 2014-01-08, 最終更新日: 2024-10-23)

主引用文献

Knott, B.C.,Haddad Momeni, M.,Crowley, M.F.,Mackenzie, L.F.,Gotz, A.W.,Sandgren, M.,Withers, S.G.,Stahlberg, J.,Beckham, G.T.
The Mechanism of Cellulose Hydrolysis by a Two-Step, Retaining Cellobiohydrolase Elucidated by Structural and Transition Path Sampling Studies.
J.Am.Chem.Soc., 136:321-, 2014

PubMed Abstract: Glycoside hydrolases (GHs) cleave glycosidic linkages in carbohydrates, typically via inverting or retaining mechanisms, the latter of which proceeds via a two-step mechanism that includes formation of a glycosyl-enzyme intermediate. We present two new structures of the catalytic domain of Hypocrea jecorina GH Family 7 cellobiohydrolase Cel7A, namely a Michaelis complex with a full cellononaose ligand and a glycosyl-enzyme intermediate, that reveal details of the 'static' reaction coordinate. We also employ transition path sampling to determine the 'dynamic' reaction coordinate for the catalytic cycle. The glycosylation reaction coordinate contains components of forming and breaking bonds and a conformational change in the nucleophile. Deglycosylation proceeds via a product-assisted mechanism wherein the glycosylation product, cellobiose, positions a water molecule for nucleophilic attack on the anomeric carbon of the glycosyl-enzyme intermediate. In concert with previous structures, the present results reveal the complete hydrolytic reaction coordinate for this naturally and industrially important enzyme family.

PubMed: 24341799
DOI: 10.1021/JA410291U

実験手法

X-RAY DIFFRACTION (1.45 Å)