6P2M

Crystal structure of the Caldicellulosiruptor lactoaceticus GH74 (ClGH74a) enzyme in complex with LLG xyloglucan

6P2M の概要

• エントリーDOI: 10.2210/pdb6p2m/pdb
• 関連するPDBエントリー: 6P2K 6P2L 6P2N 6P2O
• 分子名称: Type 3a cellulose-binding domain protein, beta-D-galactopyranose-(1-2)-alpha-D-xylopyranose-(1-6)-beta-D-glucopyranose-(1-4)-[beta-D-galactopyranose-(1-2)-alpha-D-xylopyranose-(1-6)]beta-D-glucopyranose-(1-4)-beta-D-glucopyranose, 3,6,9,12,15,18,21,24,27,30,33,36,39-TRIDECAOXAHENTETRACONTANE-1,41-DIOL, ... (6 entities in total)
• 機能のキーワード: glycosyl hydrolase, gh74, xyloglucanase, 7-fold beta-propeller, hydrolase
• 由来する生物種: Caldicellulosiruptor lactoaceticus 6A
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 76890.03

構造登録者

Stogios, P.J.,Skarina, T.,Arnal, G. (登録日: 2019-05-21, 公開日: 2019-07-31, 最終更新日: 2023-10-11)

主引用文献

Arnal, G.,Stogios, P.J.,Asohan, J.,Attia, M.A.,Skarina, T.,Viborg, A.H.,Henrissat, B.,Savchenko, A.,Brumer, H.
Substrate specificity, regiospecificity, and processivity in glycoside hydrolase family 74.
J.Biol.Chem., 294:13233-13247, 2019

PubMed Abstract: Glycoside hydrolase family 74 (GH74) is a historically important family of -β-glucanases. On the basis of early reports of detectable activity on cellulose and soluble cellulose derivatives, GH74 was originally considered to be a "cellulase" family, although more recent studies have generally indicated a high specificity toward the ubiquitous plant cell wall matrix glycan xyloglucan. Previous studies have indicated that GH74 xyloglucanases differ in backbone cleavage regiospecificities and can adopt three distinct hydrolytic modes of action: , -dissociative, and -processive. To improve functional predictions within GH74, here we coupled in-depth biochemical characterization of 17 recombinant proteins with structural biology-based investigations in the context of a comprehensive molecular phylogeny, including all previously characterized family members. Elucidation of four new GH74 tertiary structures, as well as one distantly related dual seven-bladed β-propeller protein from a marine bacterium, highlighted key structure-function relationships along protein evolutionary trajectories. We could define five phylogenetic groups, which delineated the mode of action and the regiospecificity of GH74 members. At the extremes, a major group of enzymes diverged to hydrolyze the backbone of xyloglucan nonspecifically with a dissociative mode of action and relaxed backbone regiospecificity. In contrast, a sister group of GH74 enzymes has evolved a large hydrophobic platform comprising 10 subsites, which facilitates processivity. Overall, the findings of our study refine our understanding of catalysis in GH74, providing a framework for future experimentation as well as for bioinformatics predictions of sequences emerging from (meta)genomic studies.

PubMed: 31324716
DOI: 10.1074/jbc.RA119.009861

実験手法

X-RAY DIFFRACTION (1.98 Å)