7EE2

Structural insights into the substrate-binding mechanism of a glycoside hydrolase family 12 beta-1,3-1,4-glucanase from Chaetomium sp.CQ31

7EE2 の概要

• エントリーDOI: 10.2210/pdb7ee2/pdb
• 分子名称: glycoside hydrolase family 12 beta-1,3-1,4-glucanase, GLYCEROL (3 entities in total)
• 機能のキーワード: beta-1, 3-1, 4-glucanase, hydrolase, catalytic mechanism, substrate binding, structural protein
• 由来する生物種: Chaetomium sp.
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 25846.30

構造登録者

Jiang, Z.Q.,Ma, J. (登録日: 2021-03-17, 公開日: 2022-03-23, 最終更新日: 2024-11-20)

主引用文献

Ma, J.,Li, Y.,Han, S.,Jiang, Z.,Yan, Q.,Yang, S.
Structural and biochemical insights into the substrate-binding mechanism of a glycoside hydrolase family 12 beta-1,3-1,4-glucanase from Chaetomium sp.
J.Struct.Biol., 213:107774-107774, 2021

PubMed Abstract: β-1,3-1,4-Glucanases are a type of hydrolytic enzymes capable of catalyzing the strict cleavage of β-1,4 glycosidic bonds adjacent to β-1,3 linkages in β-D-glucans and have exhibited great potential in food and feed industrials. In this study, a novel glycoside hydrolase (GH) family 12 β-1,3-1,4-glucanase (CtGlu12A) from the thermophilic fungus Chaetomium sp. CQ31 was identified and biochemically characterized. CtGlu12A was most active at pH 7.5 and 65 °C, respectively, and exhibited a high specific activity of 999.9 U mg towards lichenin. It maintained more than 80% of its initial activity in a wide pH range of 5.0-11.0, and up to 60 °C after incubation at 55 °C for 60 min. Moreover, the crystal structures of CtGlu12A with gentiobiose and tetrasccharide were resolved. CtGlu12A had a β-jellyroll fold, and performed retaining mechanism with two glutamic acids severing as the catalytic residues. In the complex structure, cellobiose molecule showed two binding modes, occupying subsites -2 to -1 and subsites + 1 to + 2, respectively. The concave cleft made mixed β-1,3-1,4-glucan substrates maintain a bent conformation to fit into the active site. Overall, this study is not only helpful for the understanding of the substrate-binding model and catalytic mechanism of GH 12 β-1,3-1,4-glucanases, but also provides a basis for further enzymatic engineering of β-1,3-1,4-glucanases.

PubMed: 34329700
DOI: 10.1016/j.jsb.2021.107774
主引用文献が同じPDBエントリー

実験手法

X-RAY DIFFRACTION (1.37011635113 Å)