The catalytic domain (residues 128–449) of the Orpinomyces sp. Y102 CelC7 enzyme (Orp CelC7) exhibits cellobiohydrolase and cellotriohydrolase activities. Crystal structures of Orp CelC7 and its cellobiose‐bound complex have been solved at resolutions of 1.80 and 2.78 Å, respectively. Cellobiose occupies subsites +1 and +2 within the active site of Orp CelC7 and forms hydrogen bonds to two key residues: Asp248 and Asp409. Furthermore, its substrate‐binding sites have both tunnel‐like and open‐cleft conformations, suggesting that the glycoside hydrolase family 6 (GH6) Orp CelC7 enzyme may perform enzymatic hydrolysis in the same way as endoglucanases and cellobiohydrolases. LC‐MS/MS analysis revealed cellobiose (major) and cellotriose (minor) to be the respective products of endo and exo activity of the GH6 Orp CelC7.

中文翻译：

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GH6 Orpinomyces sp。的晶体结构。具有外切和内切活性的Y102 CelC7酶及其与纤维二糖的复合物。

Orpinomyces sp的催化域（残基128–449）。Y102 CelC7酶（Orp CelC7）具有纤维二糖水解酶和纤维二糖水解酶活性。Orp CelC7及其纤维二糖结合复合物的晶体结构已分别以1.80和2.78Å的分辨率进行了解析。纤维二糖占据Orp CelC7活性位点内的亚位+1和+2，并与两个关键残基形成氢键：Asp248和Asp409。此外，其底物结合位点同时具有隧道样和开裂构象，表明糖苷水解酶家族6（GH6）OrpCelC7酶可以与内切葡聚糖酶和纤维二糖水解酶相同的方式进行酶促水解。LC-MS / MS分析表明，纤维二糖（主要）和纤维三糖（次要）分别是GH6 Orp CelC7的内切和外切活性的产物。