Biotransformation and Biocatalysis, Groningen Biomolecular Science and Biotechnology Institute, University of Groningen, Groningen, The Netherlands.
Appl Environ Microbiol. 2013 Sep;79(18):5625-32. doi: 10.1128/AEM.01479-13. Epub 2013 Jul 12.
Through genome mining, we identified a gene encoding a putative serine protease of the thermitase subgroup of subtilases (EC 3.4.21.66) in the thermophilic bacterium Coprothermobacter proteolyticus. The gene was functionally expressed in Escherichia coli, and the enzyme, which we called proteolysin, was purified to near homogeneity from crude cell lysate by a single heat treatment step. Proteolysin has a broad pH tolerance and is active at temperatures of up to 80°C. In addition, the enzyme shows good activity and stability in the presence of organic solvents, detergents, and dithiothreitol, and it remains active in 6 M guanidinium hydrochloride. Based on its stability and activity profile, proteolysin can be an excellent candidate for applications where resistance to harsh process conditions is required.
通过基因组挖掘，我们在嗜热细菌Coprothermobacter proteolyticus 中鉴定出一个编码丝氨酸蛋白酶的基因，该酶属于枯草杆菌蛋白酶亚群的热稳定酶（EC 3.4.21.66）。该基因在大肠杆菌中得到功能性表达，我们将该酶命名为蛋白酶，它可以通过单一的热处理步骤从粗细胞裂解物中纯化到近乎均一的状态。蛋白酶具有广泛的 pH 耐受性，在高达 80°C 的温度下具有活性。此外，该酶在有机溶剂、洗涤剂和二硫苏糖醇存在下具有良好的活性和稳定性，并且在 6 M 盐酸胍中仍然保持活性。根据其稳定性和活性谱，蛋白酶可以成为需要抵抗恶劣工艺条件的应用的优秀候选者。
