a College of Food Science and Biotechnology , Zhejiang Gongshang University , Hangzhou , People's Republic of China.
Prep Biochem Biotechnol. 2019;49(7):718-726. doi: 10.1080/10826068.2019.1605526. Epub 2019 May 3.
A propanol-tolerant neutral protease was purified and characterized from sp. ZG20 in this study. This protease was purified to homogeneity with a specific activity of 26,655 U/mg. The recovery rate and purification fold of the protease were 13.7% and 31.5, respectively. The SDS-PAGE results showed that the molecular weight of the protease was about 29 kDa. The optimal temperature and pH of the protease were 45 °C and 7.0, respectively. The protease exhibited a good thermal- and pH stability, and was tolerant to 50% propanol. Mg, Zn, K, Na and Tween-80 could improve its activity. The calculated and values of the protease towards α-casein were 12.74 mg/mL and 28.57 µg/(min mL), respectively. This study lays a good foundation for the future use of the neutral protease from sp. ZG20.
本研究从 sp. ZG20 中纯化和表征了一种耐丙醇的中性蛋白酶。该蛋白酶经纯化后比活性达到 26655 U/mg，回收率和纯化倍数分别为 13.7%和 31.5。SDS-PAGE 结果表明，该蛋白酶的分子量约为 29 kDa。该蛋白酶的最适温度和 pH 分别为 45°C 和 7.0。该蛋白酶具有良好的热稳定性和 pH 稳定性，并且能够耐受 50%的丙醇。Mg、Zn、K、Na 和 Tween-80 可以提高其活性。该蛋白酶对α-酪蛋白的 和 值分别为 12.74 mg/mL 和 28.57 µg/(min·mL)。本研究为今后利用 sp. ZG20 的中性蛋白酶奠定了良好的基础。
