Li Tongbiao, Wang Ruilin, Hua Beibei, Cao Lianbin, Zhang Qing, Zhai Yuanyuan, Ling Shaohua, Wang Mingcheng, Li Enzhong
College of Biological and Food Engineering, Huanghuai University, Zhumadian 463000, China.
College of Life Sciences, Anhui Medical University, Hefei 230000, Anhui, China.
J Agric Food Chem. 2025 Jan 15;73(2):1516-1528. doi: 10.1021/acs.jafc.4c10256. Epub 2025 Jan 1.
The thermostability and catalytic activity of GH11 xylanase XynASP from JOP 1030-1 were improved by systematically engineering the cord region. Ultimately, mutant DSM4 was developed through iterative combinations of mutations. Compared to the wild-type XynASP, DSM4 showed a 130.9- and 9.3-fold increase in and catalytic efficiency, respectively. Reducing the flexibility of the cord region boosted the overall rigidity, resulting in improved thermal stability. The extensive catalytic cleft and prolonged contact between catalytic residues and the substrate were likely key factors in enhancing catalytic activity. Maintaining the thumb highly flexible can offset the negative impact on catalytic activity during the thermal stability modification of the cord region. This study indicates that the cord region is an effective target for enhancing the thermostability and catalytic activity of GH11 xylanase through engineered modifications.
通过对连接区进行系统工程改造，提高了来自JOP 1030-1的GH11木聚糖酶XynASP的热稳定性和催化活性。最终，通过迭代组合突变开发出了突变体DSM4。与野生型XynASP相比，DSM4的热稳定性和催化效率分别提高了130.9倍和9.3倍。降低连接区的灵活性增强了整体刚性，从而提高了热稳定性。广泛的催化裂隙以及催化残基与底物之间延长的接触可能是增强催化活性的关键因素。保持拇指高度灵活可以抵消在连接区热稳定性修饰过程中对催化活性的负面影响。本研究表明，连接区是通过工程改造提高GH11木聚糖酶热稳定性和催化活性的有效靶点。
