Structure-guided engineering of a Thermobifida fusca cutinase for enhanced hydrolysis on natural polyester substrate
Qilei Dong, Shuguang Yuan, Lian Wu, Lingqia Su, Qiaoling Zhao, Jing Wu, Weixue Huang, Jiahai Zhou
Abstract
Abstract Cutinases could degrade insoluble polyester, including natural cutin and synthetic plastic. However, their turnover efficiency for polyester remains too low for industrial application. Herein, we report the 1.54-Å resolution X-ray crystal structure of a cutinase from Thermobifida fusca and modeling structure in complex with a cutin mimic oligo-polyester C 24 H 42 O 8 . These efforts subsequently guided our design of cutinase variants with less bulky residues in the vicinity of the substrate binding site. The L90A and I213A variants exhibit increased hydrolysis activity (5- and 2.4-fold, respectively) toward cutin and also showed enhanced cotton scouring efficiency compared with the wild-type enzyme.