Liu Fengling, Wang Bin, Ye Yanrui, Pan Li
School of Biology and Biological Engineering, South China University of Technology, Guangzhou, Guangdong, 510006, China.
School of Biology and Biological Engineering, South China University of Technology, Guangzhou, Guangdong, 510006, China; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, Guangzhou 510006, China.
Protein Expr Purif. 2018 Apr;144:71-75. doi: 10.1016/j.pep.2017.11.003. Epub 2017 Nov 21.
Tannin acyl hydrolase (tannase, EC3.1.1.20) catalyzes the hydrolysis of hydrolyzable tannins. It is used in the manufacture of instant tea and in the production of gallic acid. In this study, we reported that the overexpression, purification and characterization of an Aspergillus niger tannase. The tannase gene was cloned from A. niger SH-2 and expressed in the A. niger strain Bdel4 which is low-background of secreted proteins. The recombinant tannase was purified by desalting, followed by gel filtration for characterization. The tannase activity achieved 111.5 U/mL at 168 h, and the purity of the enzyme in the broth supernatant was estimated to be over 70%. The optimum temperature and pH of the recombinant tannase was ∼40 °C and 7.0, respectively. The tannase activity was inhibited by Mg, Ca, Cu, Ba, Ni and EDTA, and was enhanced by Mn and Co. Since A. niger is a GRAS microorganism, the recombinant tannase could be purification-free due to its high purity. The results of this study suggested that this recombinant strain could be subjected to large-scale production of A. niger tannase.
单宁酰基水解酶（单宁酶，EC3.1.1.20）催化可水解单宁的水解反应。它用于速溶茶的制造以及没食子酸的生产。在本研究中，我们报道了黑曲霉单宁酶的过表达、纯化及特性分析。单宁酶基因从黑曲霉SH - 2中克隆，并在分泌蛋白背景低的黑曲霉菌株Bdel4中表达。重组单宁酶先通过脱盐纯化，然后进行凝胶过滤以进行特性分析。在168小时时，单宁酶活性达到111.5 U/mL，肉汤上清液中酶的纯度估计超过70%。重组单宁酶的最适温度和pH分别约为40℃和7.0。单宁酶活性受到Mg、Ca、Cu、Ba、Ni和EDTA的抑制，而受到Mn和Co的增强。由于黑曲霉是一种公认安全的微生物，重组单宁酶因其高纯度而无需纯化。本研究结果表明，该重组菌株可用于大规模生产黑曲霉单宁酶。
