文献类型：期刊文献

英文题名：Insights into the Interaction Mechanism of Protocatechuate 3,4-Dioxygenase with Substrates via Multispectroscopy and Molecular Docking

作者：Cheng, Jiliang[1,2,3] Du, Huan[4] Jiang, Shan-Shan[1] Liu, Xiao-Jie[1] Zheng, Nian-Jue[1] Ye, Jin-Cheng[1] Zhang, Dina[2,3] Xin, Kun[2,3] Xiang, Lei[1] Li, Yan-Wen[1] Cai, Quan-Ying[1] Mo, Ce-Hui[1] Zhao, Hai-Ming[1,5]

第一作者：Cheng, Jiliang

通信作者：Mo, CH[1];Zhao, HM[1];Zhao, HM[2]

机构：[1]Jinan Univ, Coll Life Sci & Technol, Guangdong Prov Res Ctr Environm Pollut Control & R, Guangzhou 510632, Peoples R China;[2]Chinese Acad Forestry, Res Inst Trop Forestry, State Key Lab Wetland Conservat & Restorat, Guangzhou 510520, Peoples R China;[3]Dongzhaigang Long Term Res Stn Mangrove Wetland Ec, Haikou 571129, Peoples R China;[4]Guangzhou Customs Technol Ctr, Guangzhou 510623, Peoples R China;[5]Sun Yat Sen Univ, Guangdong Prov Key Lab Environm Pollut Control & R, Guangzhou 510275, Peoples R China

年份：2025

卷号：73

期号：40

起止页码：25222-25237

外文期刊名：JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY

收录：;EI(收录号：20254219323689);Scopus(收录号：2-s2.0-105018011944);WOS:【SCI-EXPANDED(收录号:WOS:001584767900001)】；

基金：This work was funded by the National Natural Science Foundation of China (42107222, 42030713), the Guangdong Basic and Applied Basic Research Foundation (2025A1515012790, 2023A1515110102, 2024A1515011143), the Leading Talents Program of Guangdong Special Support Plan (No. NYLJ2024003), the "Daxiansheng" tutor training program of Jinan university (YDXS2403), the Research Fund Program of Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (2023B1212060016), the Special Funds for the Cultivation of Guangdong College Students' Scientific and Technological Innovation (pdjh2024b057), and the Outstanding Innovative Talents Cultivation Funded Programs for Doctoral Students of Jinan University (2024CXB018).

语种：英文

外文关键词：aromatic compounds; protocatechuate 3,4-dioxygenase; microbial degradation; protocatechuic acid

摘要：Protocatechuic acid (PCA) is a key intermediate in aromatic pollutant biodegradation, and protocatechuate 3,4-dioxygenase (3,4-PCD) can efficiently cleave its aromatic ring. The interaction mechanism remains incompletely understood. This study investigated the interaction mechanism between PCA and a 3,4-PCD from Rhodococcus sp. 2G. The recombinant enzyme was heterologously expressed in Escherichia coli, yielding 2.7 mg/L with high catalytic efficiency. Fluorescence quenching confirmed static quenching and efficient complex formation. Multispectral analysis revealed conformational and microenvironmental changes upon PCA binding. Integrated molecular dynamics simulations and site-directed mutagenesis identified Tyr253, Tyr337, His389, His391, and Arg386 as synergistic residues for PCA ring cleavage, with hydrogen bonds and electrostatic interactions being crucial. A refined catalytic mechanism was proposed. These findings provide deep biophysical insights into 3,4-PCD/PCA interactions, advance mechanistic knowledge of dioxygenases in aromatic catabolism, and offer a basis for enzyme engineering to reduce pollutants in agricultural and food systems.