Institute of Grain and Oil Quality and Safety, Academy of National Food and Strategic Reserves Administration, No.11 Baiwanzhuang Street, Xicheng District, Beijing 100037, China.
School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
Toxins (Basel). 2023 Aug 4;15(8):492. doi: 10.3390/toxins15080492.
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.
在这项研究中，我们首次从幼虫粪便中筛选出了一种具有氧化脱氧雪腐镰刀菌烯醇（DON）为 3-酮-DON 能力的双成员细菌联合体，命名为 SD。该联合体由 sp. SD17-1 和 sp. SD17-2 组成，这是通过基于 16S rRNA 的系统发育分析确定的。温度为 30°C、pH 值为 8.0-9.0 以及初始接种物浓度比为 0.1 的条件是细菌联合体 SD 氧化 DON 活性的最佳单因素参数。基于基因组的生物信息学分析显示，在 sp. SD17-1 和 sp. SD17-2 的基因组中分别存在完整的 PQQ 生物合成操纵子（）和四个假定的吡咯喹啉醌（PQQ）依赖性醇脱氢酶（ADH）基因。生化分析进一步证实了 sp. 的 PQQ 产生表型以及 sp. 中四个 PQQ 依赖性 ADHs 中的两个的 DON 氧化酶活性。添加含有 PQQ 的来自 sp. 的无细胞发酵上清液激活了 sp. 的 DON 氧化活性。总之，作为 SD 细菌联合体的成员，sp. 和 sp. 在 SD 氧化 DON 方面发挥着不可或缺的互补作用。具体而言，sp. 负责产生必要的 PQQ 辅助因子，而 sp. 表达 PQQ 依赖性 DON 脱氢酶，共同促进 DON 的氧化。
