論文 - 詳細
| RRC ID | 50817 |
|---|---|
| 著者 | Abe K, Nakajima M, Yamashita T, Matsunaga H, Kamisuki S, Nihira T, Takahashi Y, Sugimoto N, Miyanaga A, Nakai H, Arakawa T, Fushinobu S, Taguchi H. |
| タイトル | Biochemical and structural analyses of a bacterial endo-β-1,2-glucanase reveal a new glycoside hydrolase family. |
| ジャーナル | J Biol Chem |
| Abstract |
β-1,2-Glucan is an extracellular cyclic or linear polysaccharide from Gram-negative bacteria, with important roles in infection and symbiosis. Despite β-1,2-glucan's importance in bacterial persistence and pathogenesis, only a few reports exist on enzymes acting on both cyclic and linear β-1,2-glucan. To this end, we purified an endo-β-1,2-glucanase to homogeneity from cell extracts of the environmental species Chitinophaga arvensicola, and an endo-β-1,2-glucanase candidate gene (Cpin_6279) was cloned from the related species Chitinophaga pinensis The Cpin_6279 protein specifically hydrolyzed linear β-1,2-glucan with polymerization degrees of ≥5 and a cyclic counterpart, indicating that Cpin_6279 is an endo-β-1,2-glucananase. Stereochemical analysis demonstrated that the Cpin_6279-catalyzed reaction proceeds via an inverting mechanism. Cpin_6279 exhibited no significant sequence similarity with known glycoside hydrolases (GHs), and thus the enzyme defines a novel GH family, GH144. The crystal structures of the ligand-free and complex forms of Cpin_6279 with glucose (Glc) and sophorotriose (Glc-β-1,2-Glc-β-1,2-Glc) determined up to 1.7 Å revealed that it has a large cavity appropriate for polysaccharide degradation and adopts an (α/α)6-fold slightly similar to that of GH family 15 and 8 enzymes. Mutational analysis indicated that some of the highly conserved acidic residues in the active site are important for catalysis, and the Cpin_6279 active-site architecture provided insights into the substrate recognition by the enzyme. The biochemical characterization and crystal structure of this novel GH may enable discovery of other β-1,2-glucanases and represent a critical advance toward elucidating structure-function relationships of GH enzymes. |
| 巻・号 | 292(18) |
| ページ | 7487-7506 |
| 公開日 | 2017-5-5 |
| DOI | 10.1074/jbc.M116.762724 |
| PII | S0021-9258(20)42860-1 |
| PMID | 28270506 |
| PMC | PMC5418048 |
| MeSH | Bacterial Proteins / chemistry* Bacterial Proteins / isolation & purification Bacteroidetes / enzymology* Catalysis Catalytic Domain Cellulase / chemistry* Cellulase / isolation & purification Crystallography, X-Ray |
| IF | 4.238 |
| 引用数 | 15 |
| オルトメトリクス指標 |
オルトメトリクス指標項目
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| 最多言及媒体 | X(Twitter) |
| 各媒体での言及数の合計 | 35 |
| 過去6か月間でのオルトメトリクス指標の変動値 | 0.0 |
| リソース情報 | |
| 一般微生物 | JCM 2839 |