Identification of a Bacillus amyloliquefaciens H6 Thioesterase Involved in Zearalenone Detoxification by Transcriptomic Analysis

Abstract

Zearalenone (ZEA), a nonsteroidal estrogenic mycotoxin produced by Fusarium graminearum, induces hyperestrogenic responses in mammals and can cause reproductive disorders in farm animals. In this study, a transcriptome analysis of Bacillus amyloliquefaciens H6, which was previously identified as a ZEA-degrading bacterium, was conducted with high-throughput sequencing technology, and the differentially expressed genes were subjected to gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) enrichment analyses. Among the 16 upregulated genes, BAMF_RS30125 was predicted to be the key gene responsible for ZEA degradation. The protein encoded by BAMF_RS30125 was then expressed in Escherichia coli, and this recombinant protein (named ZTE138) significantly reduced the ZEA content, as determined by the enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC), and decreased the proliferating activity of ZEA in MCF-7 cells. What is more, the liquid chromatography–tandem mass spectrometry (LC–MS/MS) results showed that the relative molecular mass and the structure of ZEA also changed. Sequence alignment of the ZTE138 protein showed that it is a protease that belongs to the YBGC/FADM family of coenzyme A thioesterases, and thus, the protein can presumably cleave the ZEA lactone bond and break down its macrolide ring.

Exploration on the Enhancement of Detoxification Ability of Zearalenone and Its Degradation Products of Aspergillus niger FS10 under Directional Stress of Zearalenone

“…ZEN poisoning can be categorized into acute poisoning and chronic poisoning. In acute poisoning, the animals show restless excitement, staggering, muscle tremor, and sudden death [5]. Cyanosis of the mucous membrane and the absence of an apparent change in body temperature are also present [6].…”

Destruction of Mycotoxins in Poultry Waste under Anaerobic Conditions within Methanogenesis Catalyzed by Artificial Microbial Consortia

“…To improve representative sampling before screening in anaerobic microbial consortia, the number of enzymes destructing various mycotoxins was enlarged by laccase Bv Lac103 and peroxidase Rh DypB both acting on AFs [ 87 , 88 ], by PQQ-dependent reductase Ph DDH and aldo-keto reductase Rl DepB both modifying DON [ 89 , 90 ], by amine oxidase An FAO and Mn-dependent peroxidase Gs MnP both degrading FUMs [ 91 , 92 ], and by novel thioesterase Ba ZTE138 hydrolyzing ZEN [ 93 ]. Initially, there was a bias towards the pre-selection of these enzymes precisely inside the microorganisms composing different methanogenic microbial consortia.…”

Post-Harvest Prevention of Fusariotoxin Contamination of Agricultural Products by Irreversible Microbial Biotransformation: Current Status and Prospects

“…Coenzyme A thioesterases . Transcriptomic analysis of Bacillus amyloliquefaciens H6 possessing ZEN-degrading activity revealed a BAMF_RS30125 gene associated with this activity [ 91 ]. The corresponding recombinant protein ZTE138 reduced the ZEN content in the medium by 59.79% after a 72 h incubation at 37 °C and also almost thrice reduced ZEN-promoted proliferation in MCF-7 cells.…”