Biotransformation of Deoxynivalenol by a Dual-Member Bacterial Consortium Isolated from Larval Feces.

In this study, a dual-member bacterial consortium with the ability to oxidize deoxynivalenol (DON) to 3-keto-DON, designated SD, was first screened from the feces of larvae. This consortium consisted of sp. SD17-1 and sp. SD17-2, as determined by 16S rRNA-based phylogenetic analysis. A temperature of 30 °C, a pH of 8.0-9.0, and an initial inoculum concentration ratio of to of 0.1 were optimal single-factor parameters for the DON oxidation activity of the bacterial consortium SD. Genome-based bioinformatics analysis revealed the presence of an intact PQQ biosynthesis operon () and four putative pyrroloquinoline quinone (PQQ)-dependent alcohol dehydrogenase (ADH) genes in the genomes of strain SD17-1 and strain SD17-2, respectively. Biochemical analyses further confirmed the PQQ-producing phenotype of and the DON-oxidizing enzymatic activities of two of four PQQ-dependent ADHs in . The addition of PQQ-containing a cell-free fermentation supernatant from activated DON-oxidizing activity of . In summary, as members of the bacterial consortium SD, and play indispensable and complementary roles in SD's oxidation of DON. Specifically, is responsible for producing the necessary PQQ cofactor, whereas expresses the PQQ-dependent DON dehydrogenase, together facilitating the oxidation of DON.