Aerobic denitrifying bacteria community structure and response of aerobic denitrifying bacteria to dissloved organic matter in the sediments in Lake Baiyangdian in the spring

Abstract

好氧反硝化因其独特优势成为近年来生物脱氮的研究热点，溶解性有机物（DOM）作为微生物碳源是造成群落差异的重要原因，为了探究白洋淀不同功能区好氧反硝化菌群落结构对溶解性有机物碳源的响应，本文结合荧光区域积分法以及napA反硝化基因的高通量测序技术，对白洋淀春季沉积物中的好氧反硝化菌群落结构特征以及好氧反硝化菌对溶解性有机物的响应进行研究.结果表明，春季白洋淀沉积物有机质组分类蛋白质组分高于类腐殖质组分，其中养殖区的类蛋白质组分最大，达到79.63%±3.79%，原始区的类腐殖质组分最大，达到33.91%±6.32%；高通量测序得到3693个OTUs，共分为9个主要门类，其中，变形菌门占比最大，达到99%以上；α多样性Chao1指数呈现显著的空间差异，并且旅游区>生活区>入淀区>原始区>养殖区；该时期好氧反硝化菌主要物种组成包括Aeromonas、Sulfuritortus、Cupriavidus、Pseudomonas和Thauera，Ferrimonas作为指示物种，差异贡献最大；冗余分析发现，可见光区类富里酸物质和微生物代谢产物组分分别是不同功能区好氧反硝化菌群落纲水平和属水平差异的主要原因.综上，通过对白洋淀好氧反硝化菌群与溶解性有机物的相关关系研究，不仅有助于进一步认识天然环境中氮循环微生物的特征；还可以为将来适于实际环境的高效菌筛选的碳源选择提供参考.;Aerobic denitrification has become a research hotspot in biological denitrification in recent years due to its unique advantages. Dissolved organic matter (DOM) as a carbon source is the important reason for community differences. To explore the responding mechanism of aerobic denitrifying bacteria community structure to dissolved organic matter in different functional areas of Lake Baiyangdian, this paper combines the fluorescence area integration method and the high-throughput sequencing technology of napA denitrification genes to study the characteristics of the aerobic denitrifying bacterial community structure and responding mechanism in Lake Baiyangdian. The results showed that the concentration of protein-like components was higher than that of humic-like components in the organic matter of Lake Baiyangdian sediments in spring. Among them, the protein-like components in the culture area were the largest, reaching 79.63%±3.79%, and the humus-like component in the primitive area was the largest, reaching 33.91%±6.32%; A total of 3693 OTUs were acquired high Throughput sequencing, which was divided into 9 main phyla. Among them, the Proteobacteria accounted for the largest proportion, reaching over 99%; the α diversity Chao1 index showed significant spatial differences, and the travel area>the living area>the entry area>the original area>the breeding area; the main species of aerobic denitrifying bacteria include Aeromonas, Sulfuritortus, Cupriavidus, Pseudomonas and Thaurea, Ferrimonas, as an indicator species, contributes the most to the difference; Redundant analysis found that the components of fulvic acid-like substances and microbial metabolites in the visible light area are the main reasons for the differences in aerobic denitrifying bacteria in different functional areas. In summary, this research will not only help to further understand the characteristics of the nitrogen cycle microorganisms in the natural environment; it will also provide a reference for the selection of carbon sources suitable for efficient bacterial screening in the practical environment.