Department of Biotechnology, College of Food Science and Nutritional Engineering, China Agricultural University, No.17 Qinghua Donglu, Haidian District, PO Box 294, Beijing, 100083, China.
J Ind Microbiol Biotechnol. 2014 Oct;41(10):1487-95. doi: 10.1007/s10295-014-1494-4. Epub 2014 Aug 12.
A novel alkaline β-1,3-1,4-glucanase (McLic1) from a thermophilic fungus, Malbranchea cinnamomea, was purified and biochemically characterized. McLic1 was purified to homogeneity with a purification fold of 3.1 and a recovery yield of 3.7 %. The purified enzyme was most active at pH 10.0 and 55 °C, and exhibited a wide range of pH stability (pH 4.0-10.0). McLic1 displayed strict substrate specificity for barley β-glucan, oat β-glucan and lichenan, but did not show activity towards other tested polysaccharides and synthetic p-nitrophenyl derivates, suggesting that it is a specific β-1,3-1,4-glucanase. The K m values for barley β-glucan, oat β-glucan and lichenan were determined to be 0.69, 1.11 and 0.63 mg mL(-1), respectively. Moreover, the enzyme was stable in various non ionic surfactants, oxidizing agents and several commercial detergents. Thus, the alkaline β-1,3-1,4-glucanase may have potential in industrial applications, such as detergent, paper and pulp industries.
一种新型的嗜热真菌 Malbranchea cinnamomea 的碱性β-1,3-1,4-葡聚糖酶（McLic1）被分离和生化特性分析。McLic1 通过 3.1 倍的纯化倍数和 3.7%的回收率达到了均一性。该酶最适 pH 值为 10.0，最适温度为 55°C，且在 pH4.0-10.0 范围内具有较宽的 pH 稳定性。McLic1 对大麦葡聚糖、燕麦葡聚糖和地衣聚糖具有严格的底物特异性，但对其他测试的多糖和合成的对硝基苯衍生物没有活性，表明它是一种特异性的β-1,3-1,4-葡聚糖酶。该酶对大麦葡聚糖、燕麦葡聚糖和地衣聚糖的 K m 值分别为 0.69、1.11 和 0.63mg mL(-1)。此外，该酶在各种非离子表面活性剂、氧化剂和几种商业洗涤剂中稳定。因此，碱性β-1,3-1,4-葡聚糖酶在工业应用中具有潜在的应用价值，如洗涤剂、造纸和纸浆工业。
