New Hydrolase from Aeromicrobium sp. HA for the Biodegradation of Zearalenone: Identification, Mechanism, and Application

作者：Junqiang Hu, Gang Wang, Mingxuan Hou, Shilong Du, Jun Han, Yangguang Yu, Hongxia Gao, Dan He, Jianrong Shi, Yin‐Won Lee, Sherif R. Mohamed, Dawood H. Dawood, Qing Hong, Xin Liu, Jianhong Xu · 发表于：Journal of Agricultural and Food Chemistry · 年份：2023 · DOI：10.1021/acs.jafc.2c06410 · 被引用次数：62 · 研究领域：Mycotoxins in Agriculture and Food、Pharmaceutical and Antibiotic Environmental Impacts、Potato Plant Research

Zearalenone (ZEN) is an estrogenic mycotoxin most frequently found in cereals that can cause reproductive disorders in livestock and pose a severe threat to animal husbandry. In this study, we isolated a ZEN-degrading Aeromicrobium strain from soil and found that ZenH, a hydrolase, is responsible for the hydrolysis of ZEN through comparative proteomics and biochemical studies. ZenH exhibited the highest similarity with lactone hydrolase ZHD607 from Phialophora americana at 21.52%. ZenH displayed maximal enzymatic activity at pH 7.0 and 55 °C with a Michaelis constant of 12.64 μM. The catalytic triad of ZenH was identified as S117-D142-H292 by molecular docking and site-directed mutagenesis. ZenH catalyzed the hydrolysis of ZEN to a novel metabolite, ( S, E )-4-hydroxy-2-(10-hydroxy-6-oxoundec-1-en-1-yl)-7-oxabicyclo[4.2.0]octa-1,3,5-trien-8-one, which exhibited significantly lower estrogenic toxicity than ZEN. This study illustrates a novel ZEN-degrading enzyme and reveals a new degradation product. Furthermore, the enzyme showed good potential for detoxifying ZEN during food processing.