高通量测序分析混合菌群中的呕吐毒素降解菌

为筛选具有降解脱氧雪腐镰刀菌烯醇（deoxynivalenol，DON）能力的微生物，利用高通量测序方法分析混合菌群中的DON降解菌。从土壤中获得具有DON降解能力的混合菌群LG-6，并发现不同梯度稀释倍数的混合菌群之间DON降解效果具有明显差异。稀释至10－7时混合菌群LG-6-7能完全降解DON，而稀释至10－8时混合菌群LG-6-8不能降解DON。对这2?个混合菌群的微生物多样性进行分析，发现混合菌群LG-6-7包括假苍白杆菌属、节细菌属、假单胞菌属、代尔夫特菌属和德沃斯氏菌属，而混合菌群LG-6-8包括假苍白杆菌属和节细菌属。故推测假单胞菌属、德沃斯氏菌属和代尔夫特菌属在降解DON的过程中必不可少。此外，假单胞菌B6-24和德沃斯氏菌A6-243混合培养时，48?h内完全降解DON。该混合菌群培养温度为37?℃、pH?7.0，培养基为MMT培养基，并发现该混合菌群是通过微生物代谢产生的酶对DON进行降解。本研究发现能完全降解DON的假单胞菌B6-24和德沃斯氏菌A6-243混合菌群，为呕吐毒素生物脱毒剂的研发提供一定理论依据。

High-throughput Sequencing Analysis of Vomitoxin-degrading Bacteria in Bacterial Consortium

Vomitoxin, also known as DON, is a secondary metabolite produced by several Fusarium sp. In order to select microorganisms capable of degrading DON, high-throughput sequencing was used to analyze DON-degrading bacteria in bacterial consortia. In this study, bacterial consortium LG-6 with DON-degrading capacity was obtained from soil, and it was found that the effect varied depending on the dilution ratio of the bacterial consortium. LG-6 diluted by a factor of 10-7 (denoted as LG-6-7) but not 10-8 (denoted as LG-6-8) could completely degrade DON. The analysis of microbial diversity demonstrated that LG-6-7 included Pseudochrobactrum, Pseudomonas, Delftia, Devosia, and Achromobacter, while LG-6-8 included only Pseudochrobactrum and Achromobacte, indicating that Pseudomonas, Devosia and Delftia are essential for the degradation of DON. In addition, DON was completely degraded within 48 h by a bacterial consortium of Pseudomonas sp. B6-24 and Devosia A6-243. The optimal culture conditions for the bacterial consortium were 37 ℃, pH 7.0, and MMT medium. Moreover, microbial enzymes from the consortium were responsible for the degradation of DON. In conclusion, a bacterial consortium of Pseudomonas sp. B6-24 and Devosia A6-243 can degrade DON completely, which will lay a foundation for the research and development of biological detoxifying agents for vomiting toxin.