College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China.
College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
Int J Biol Macromol. 2019 May 15;129:471-476. doi: 10.1016/j.ijbiomac.2019.02.056. Epub 2019 Feb 11.
In this study, chondroitinase (ChSase) AC II from Arthrobacter sp. CS01 was cloned, expressed in Escherichia coli BL21 (DE3), purified and characterised. To assist in protein folding and improve on high protein aggregation rates, two strategies involving chaperones and fusion tags were chosen to increase enzyme activity and improve enzymatic properties. ChSase AC II enzyme activity increased from 3.12 to 9.15 U/ml with chaperone GroEs-GroEL, and the specific activity increased from 19.8 to 25.74 U/mg with the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) tag. ChSase AC II and GAPDH-ChSase AC II displayed maximum activities at 37 °C and 40 °C, at pH 6.5 and 7.0, respectively. GAPDH-ChSase AC II activity remained above 69.8% after incubation at 40 °C for 120 min, and ChSase AC II activity remained approximately 32.1% under the same conditions, indicating that ChSase AC II thermostability was enhanced by the GAPDH tag. These properties suggested that the enzymes are promising prospects in medical and industrial applications.
在这项研究中,从节杆菌 CS01 中克隆、表达了软骨素酶(ChSase)AC II,并进行了纯化和特性分析。为了辅助蛋白折叠,提高高蛋白聚集率,选择了两种涉及伴侣蛋白和融合标签的策略来提高酶活性和改善酶学性质。使用 GroEs-GroEL 伴侣蛋白后,ChSase AC II 的酶活性从 3.12 U/ml 增加到 9.15 U/ml,而使用甘油醛-3-磷酸脱氢酶(GAPDH)标签后,比酶活从 19.8 U/mg 增加到 25.74 U/mg。ChSase AC II 和 GAPDH-ChSase AC II 的最适活性分别在 37°C 和 40°C、pH 6.5 和 7.0 时达到。GAPDH-ChSase AC II 在 40°C 孵育 120 分钟后,活性仍保持在 69.8%以上,而在相同条件下,ChSase AC II 的活性约为 32.1%,表明 GAPDH 标签增强了 ChSase AC II 的热稳定性。这些特性表明,这些酶在医学和工业应用中有很好的应用前景。