厌氧氨氧化细菌富集培养过程微生物结构与功能解析

为了研究厌氧氨氧化细菌富集培养过程中微生物结构与功能的关系,本研究采集升流式污泥床反应器(Upflow anaerobic sludge bed,UASB)中厌氧氨氧化反应启动与驯化过程的样品,结合传统微生物培养方法和分子生物学手段,对启动过程中的氮素转化功能基因、异养菌演替及菌群演替进行了定性与定量分析.结果表明,随...

Evolution of microbial structures and functions during the enrichment of Anammox bacteria

To study the relationship between microbial structure and function during the enrichment of annammox bacteria, sampling was carried out in an upflow anaerobic sludge bed(UASB) reactor during its start-up of anammox process, and the combined traditional microbial culture methods and molecular biological methods were used to conduct qualitative and quantitative analysis of functional genes of nitrogen transformation, evolution of heterotrophic bacteria and microbial community. Results showed that the anammox functional gene hzo was successfully enriched with the total nitrogen removal rate increased from 1.39% to 79.62%, and nirS was the key factor affecting the nitrogen removal. The dominant phylum of microbial community was Planctomycetes and the dominant genus was Candidatus Kuenenia. All these indicated that the successful enrichment of anammox was the main factor to achieve high nitrogen removal performance. Heterotrophic bacteria were symbiotic bacteria with anammox bacteria, and evolved in function, because they always occupy in a certain proportion even no organic carbon source was added in the influent. It is indicated that there is significant positive correlation between Candidatus Kuenenia and some heterotrophic bacteria such as Ignavibacterium and Gp4 based on microbial network analysis and function prediction based on KEGG database. These heterotrophic bacteria may interact with anammox by degrading or synthesizing extracellular substances and secreting secondary metabolites, which then affect the activity and growth of anammox bacteria.