Dingyu Guo, Zhengchao Wang, Wanqing Wei, Wei Song, Jing Wu, Jian Wen, Guipeng Hu, Xiaomin Li, Cong Gao, Xiulai Chen, Liming Liu
D-allulose is a naturally occurring rare sugar and beneficial to human health. However, the efficient biosynthesis of D-allulose remains a challenge. Here, we mined a new D-tagatose 3-epimerase from Kroppenstedtia eburnean (KeDt3e) with high catalytic efficiency. Initially, crucial factors contributing to the low conversion of KeDt3e were identified through crystal structure analysis, density functional theory calculations (DFT), and molecular dynamics (MD) simulations. Subsequently, based on the mechanism, combining restructuring the flexible region, proline substitution based onconsensus sequence analysis, introducing disulfide bonds, and grafting properties, and reshaping the active center, the optimal mutant M5 of KeDt3e was obtained with enhanced thermostability and activity...
April 17, 2024: Enzyme and Microbial Technology