高通量测序分析混合菌群中的呕吐毒素降解菌

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

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。

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.