College of Food Science and Engineering, Ocean University of China, Qingdao266003, China.
Sanya Ocean Institute, Ocean University of China, Sanya572024, China.
J Agric Food Chem. 2022 Sep 28;70(38):12135-12142. doi: 10.1021/acs.jafc.2c05544. Epub 2022 Sep 16.
λ-Carrageenase with high activity is an effective and environmentally friendly tool enzyme for the preparation of λ-carrageenan oligosaccharides with various biological activities. Herein, a novel GH150 (glycoside hydrolases family 150) λ-carrageenase OUC-CglA from was heterologously expressed, purified, and characterized. The recombinant OUC-CglA performs strict selectivity toward λ-carrageenan with a specific activity of 418.7 U/mg under its optimal reaction conditions of 20 °C and pH 7.0. Additionally, OUC-CglA is a typical cold-adapted λ-carrageenase because it unfolds 90% and 63% of its maximum activity at 15 and 10 °C, respectively. The hydrolysis process suggests that OUC-CglA is an endotype λ-carrageenase with the final products consisting of λ-neocarrabiose, λ-neocarratetraose, λ-neocarrahexaose, and other long-chain λ-neocarrageenan oligosaccharides. As a result, high activity, cold-adaptation, and principal products of OUC-CglA make it a potential biocatalyst for the effective preparation of λ-carrageenan oligosaccharides.
具有高活性的 λ-卡拉胶酶是一种有效且环保的工具酶，可用于制备具有各种生物活性的 λ-卡拉胶低聚糖。在此，从 中异源表达、纯化并表征了一种新型 GH150（糖苷水解酶家族 150）λ-卡拉胶酶 OUC-CglA。重组 OUC-CglA 对 λ-卡拉胶具有严格的选择性，在最佳反应条件 20°C 和 pH7.0 下的比活性为 418.7 U/mg。此外，OUC-CglA 是一种典型的耐冷 λ-卡拉胶酶，因为它在 15°C 和 10°C 下分别展开其最大活性的 90%和 63%。水解过程表明，OUC-CglA 是一种内切型 λ-卡拉胶酶，最终产物由 λ-新卡拉二糖、λ-新卡拉四糖、λ-新卡拉六糖和其他长链 λ-新卡拉胶低聚糖组成。因此，OUC-CglA 的高活性、耐冷性和主要产物使其成为有效制备 λ-卡拉胶低聚糖的潜在生物催化剂。
