4A05

Structure of the catalytic core domain of the cellobiohydrolase, Cel6A, from Chaetomium thermophilum

4A05 の概要

• エントリーDOI: 10.2210/pdb4a05/pdb
• 関連するBIRD辞書のPRD_ID: PRD_900005 PRD_900011
• 分子名称: CELLOBIOHYDROLASE FAMILY 6, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, beta-D-glucopyranose-(1-4)-beta-D-glucopyranose, ... (6 entities in total)
• 機能のキーワード: hydrolase, cellulose binding
• 由来する生物種: CHAETOMIUM THERMOPHILUM
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 41325.46

構造登録者

Thompson, A.J.,Wilson, K.S.,Davies, G.J. (登録日: 2011-09-08, 公開日: 2012-07-25, 最終更新日: 2023-12-20)

主引用文献

Thompson, A.J.,Heu, T.,Shaghasi, T.,Benyamino, R.,Jones, A.,Friis, E.P.,Wilson, K.S.,Davies, G.J.
Structure of the Catalytic Core Module of the Chaetomium Thermophilum Family Gh6 Cellobiohydrolase Cel6A.
Acta Crystallogr.,Sect.D, 68:875-, 2012

PubMed Abstract: Cellulases, including cellobiohydrolases and endoglucanases, are important enzymes involved in the breakdown of the polysaccharide cellulose. These catalysts have found widescale industrial applications, particularly in the paper and textile industries, and are now finding use in `second-generation' conversion of biomass to biofuels. Despite this considerable biotechnological application, and undoubted future potential, uncertainty remains as to the exact reaction mechanism of the inverting cellulases found in the GH6 family of carbohydrate-active enzymes. In order to gain additional understanding as to how these societally beneficial biocatalysts function, the crystal structure of a GH6 cellobiohydrolase from Chaetomium thermophilum, CtCel6A, has been solved. This structure reveals a distorted α/β-barrel fold comprising a buried tunnel-like active site quite typical of Cel6A enzymes. Analysis of an enzyme-product complex (cellobiose in the -3 and -2 subsites and cellotetraose in subsites +1 to +4) supports the hypothesis that this group of enzymes act via an atypical single-displacement mechanism. Of particular note in this analysis is an active-centre metal ion, Li(+), the position of which matches the position of the positively charged anomeric carbon of the oxocarbenium-ion-like transition state.

PubMed: 22868752
DOI: 10.1107/S0907444912016496

実験手法

X-RAY DIFFRACTION (1.9 Å)