海洋细菌 ASY5 中一种褐藻胶裂解酶 Aly1281 的特性分析及应用

Characterization and Application of an Alginate Lyase, Aly1281 from Marine Bacterium ASY5.

机构信息

College of Food and Biological Engineering, Jimei University, Xiamen 361021, China.

Fujian Provincial Engineering Technology Research Center of Marine Functional Food, Xiamen 361021, China.

出版信息

Mar Drugs. 2020 Jan 31;18(2):95. doi: 10.3390/md18020095.

Alginate extracted from widely cultured brown seaweed can be hydrolyzed by alginate lyase to produce alginate oligosaccharides (AOS) with intriguing biological activities. Herein, a novel alginate lyase Aly1281 was cloned from marine bacterium ASY5 isolated from mangrove soil and found to belong to polysaccharide lyase family 7. Aly1281 exhibited maximum activity at pH 8.0 and 50 °C and have broad substrate specificity for polyguluronate and polymannuronate. Compared with other alginate lyases, Aly1281 exhibited high degradation specificity and mainly produced di-alginate oligosaccharides which displayed good antioxidant function to reduce ferric and scavenge radicals such as hydroxyl, ABTS and DPPH. Moreover, the catalytic activity and kinetic performance of Aly1281 were highly improved with the addition of salt, demonstrating a salt-activation property. A putative conformational structural feature of Aly1281 was found by MD simulation analysis for understanding the salt-activation effect.

从广泛培养的褐藻中提取的褐藻胶可以被褐藻胶裂解酶水解，生成具有有趣生物活性的褐藻胶寡糖（AOS）。本文从红树林土壤中分离的海洋细菌 ASY5 中克隆了一种新型的褐藻胶裂解酶 Aly1281，属于多糖裂解酶家族 7。Aly1281 在 pH8.0 和 50°C 时表现出最大活性，对聚古罗糖醛酸和聚甘露糖醛酸具有广泛的底物特异性。与其他褐藻胶裂解酶相比，Aly1281 表现出较高的降解特异性，主要产生二褐藻胶寡糖，具有良好的抗氧化功能，可还原三价铁并清除羟基、ABTS 和 DPPH 等自由基。此外，添加盐可显著提高 Aly1281 的催化活性和动力学性能，表现出盐激活特性。通过 MD 模拟分析发现了 Aly1281 的一个假定构象结构特征，用于理解盐激活效应。