氧化乐果降解过程中核心菌群构建及功能解析

Construction and functional analysis of the core microbial community for omethoate degradation

现代分子生物技术可以在传统微生物研究基础上进一步对微生物群落内部信息进行分析,本文通过对氧化乐果驯化花园土过程中的微生物群落样本进行生物信息学分析,探究土壤微生物群落结构对氧化乐果的响应规律,并解析群落中核心菌群发挥的功能.结果表明,驯化过程中群落完成了对氧化乐果降解和适应的方向转变,随降解效率逐渐提升,24 d时氧化乐果降解率达到90%以上.第18~24天群落结构在门水平结构达到了稳定的状态,此时的优势菌门为拟杆菌门、变形菌门、酸杆菌门和芽单胞菌门,属水平优势群落为黄杆菌属、狭窄滋养细胞属、假单胞菌属、鞘氨醇单胞菌属和硝化螺菌属等.通过共现网络模块化划分贡献度前3的模块组成核心功能菌群,推测出对群落变化起主导作用的核心菌属,其中铁杆菌属具有最大的贡献度,黄杆菌属具有最强的菌群间连接度.最后结合PICRUSt2对驯化不同阶段的优势群落和核心功能菌群分别进行功能预测发现,在一级功能层面都是以新陈代谢功能作为最主要的功能,而在二级功能层面上具有明显差异性,主要体现在核心功能菌群具有高生长传代水平和较高的次生代谢产物生物合成水平功能上,有助于实现代谢功能的差异互补.

Modern molecular biotechnology can analyze microbial communities further compared with traditional microbial research.Bioinformatics analysis of microbial community samples was conducted for domestication of garden soil with Omega,to explore the response law of soil microbial community structure to Omega,and to analyze the functions of core microbial communities.During domestication,the community was found to have completed a directional shift towards the degradation and adaptation of omethoate.As the degradation efficiency gradually improved,the degradation rate of omethoate reached over 90%at 24 days.From 18th to 24th days,the community structure reached a stable state at the phylum level,with the dominant phylum being Bacteroidetes,Proteobacteria,Acidobacteria and Gemmatimonadetes,the dominant communities at the genus level were Flavobacterium,Stenotrophobacter,Pseudomonas,Sphingomonas,Nitrospira.By modularizing the co-occurrence network and dividing the top three contributing modules into core functional bacterial communities,it was inferred that the core bacterial genera played a dominant role in community changes.Ferruginibacter was found to have contributed the greatest,Flavobacterium had the strongest inter group connectivity.Combined with PICRUSt2,functional predictions were made for the dominant communities and core functional bacterial communities at different stages of domestication.It was found that at the primary functional level,metabolic function was the most important,but at the secondary functional level,significant differences were present;these were mainly reflected in the high growth and passage levels and high secondary metabolite biosynthesis levels of core functional bacterial communities,to achieve complementary metabolic functions.