Characterization of deoxynivalenol dehydrogenase from Pelagibacterium sp. SCN 63-126 and its application

Deoxynivalenol (DON), a type-B trichothecene mycotoxin, is primarily produced by Fusarium species and widely pollutes wheat and other grains. Enzymatic treatment of DON has been widely studied in recent years. Here, we present the biochemical identification of the DON dehydrogenase from Pelagibacterium sp. SCN 63-126 (Pe DDH). After removing the signal peptide, Pe DDH is effectively expressed in its soluble form. Biochemical identification indicates that the optimal temperature and pH of Pe DDH against DON is 35 ℃ and pH 8.5. Furthermore, Pe DDH is activated significantly in the presence of Ca²⁺, Mg²⁺, and Cu²⁺, and alternatively activated by pyrroloquinoline quinone (PQQ), phenazine methosulfate (PMS), and 2, 6-dichlorophenolindophenol (DCPIP). When PQQ, PMS, and DCPIP are combined, Pe DDH (60 µg/mL) effectively degrads DON (150 µM) in just 5 min, suggesting a synergistic effect of three cofactors on DON degradation. All these results suggest a great potential of Pe DDH in the control of DON contamination.