Rational Design for Enhancing Cellobiose Dehydrogenase Activity and Its Synergistic Role in Straw Degradation

作者：Zhengfen Wu, Pengfei Li, Yong Chen, Xihua Chen, Yong Feng, Zhongjian Guo, Daochen Zhu, Yang‐Chun Yong, Huayou Chen · 发表于：Journal of Agricultural and Food Chemistry · 年份：2024 · DOI：10.1021/acs.jafc.4c05991 · 被引用次数：18 · 研究领域：Legume Nitrogen Fixing Symbiosis、Plant-Microbe Interactions and Immunity、Polymer-Based Agricultural Enhancements

Addressing the demand for efficient biological degradation of straw, this study employed rational design coupled with structural biology and enzyme engineering techniques to enhance the catalytic activity of cellobiose dehydrogenase ( Ps CDH, CDH form Pycnoporus sanguineus ). By predicting and modifying the active site and key amino acids of Ps CDH, several CDH immobilized enzyme preparations with higher catalytic activities were successfully obtained. The excellent mutant T1 (C286Y/A461H/F464R) exhibited a 2.7-fold increase in enzyme activity compared to the wild type. Simulated calculations indicated that the enhancement of catalytic activity was primarily due to the formation of additional intermolecular interactions between CDH and the substrate, as well as the enlargement of the substrate pocket to reduce steric hindrance effects. Additionally, molecular dynamics simulation analysis revealed a potential correlation between structural stability and enzyme activity. When Ps CDH was added to a multienzyme synergistic straw degradation system, the cellulose degradation rate increased by 1.84-fold. Moreover, mutant T1 further increased the degradation of lignocellulose in the mixed system. This study provides efficient enzyme sources and modification strategies for the high-efficiency biological conversion of straw and unconventional feedstock degradation, thereby possessing significant academic value and application prospects.