异养硝化-好氧反硝化菌富集驯化过程中微生物种群演变特征——典型城市景观水系

为了研究不同异养硝化-好氧反硝化菌富集驯化过程中水体微生物群落的演变，利用Miseq高通量测序法对景观水系沉积物富集驯化样本的微生物信息进行统计，对其微生物群落的α多样性以及β多样性进行分析，同时基于微生物属的信息进行了微生物网络分析.结果显示，两种类型培养基在富集驯化完成后氮素得到有效去除，脱氮效果明显；富集驯化过程中的OUT主要属于7个，分别是变形菌门（Protebacterice）、拟杆菌门（Bacteroidetes）、绿弯菌门（Chloroflexi）、厚壁菌门（Firmicutes）、放线菌门（Actinobacteria）、蓝藻门（Cyanobacteria）、酸杆菌门（Acidobacteria），与此同时，富集驯化过程中有关氮循环的细菌有上升的变化过程；主成分分析（PCA），非度量多维尺度分析（NMDS）以及主坐标分析（PCoA）表明异养硝化-好氧反硝化菌富集驯化过程中不同温度压力下的细菌群落组成存在明显差异，而培养基的类别带来的影响相对较小；网络分析显示模块核心和网络核心均为低丰度的稀有物种；膨胀因子分析（VIF）和冗余分析（RDA）得出温度、氨氮和硝酸盐氮是影响群落结构演变的关键环境因子.综上可知，Miseq高通量测序研究异养硝化-好氧反硝化菌富集驯化过程中微生物种群演变可行，为实现微生物菌剂"定向-精准-高效"的筛选提供技术支撑.

Characteristics of bacterial community structure during the enrichment and domestication of heterotrophic nitrification-aerobic denitrification bacteria based on the typical city landscape water

To explore the effects of different selective pressures on bacterial community structure during enrichment and domestication of heterotrophic nitrification-aerobic denitrification bacteria, bioinformatics analysis of samples taken from enrichment and domestication systems were carried out, using Miseq high-throughput sequencing. In detail, α-and β-diversity were examined, and network analysis was conducted. Proteobacteria, Bacteroidetes, Chloroflexi, Firmicutes, Actinobacteria, Cyanobacteria, and Acidobacteria were the main phyla identified. Meanwhile, the N-functional bacteria had an increased process. PCA (principal component analysis), NMDS (non-metric multidimensional scaling analysis) and PCoA (principal co-ordinates analysis) showed that microbial community structure was significantly altered with change in temperature, while the influence of different media was small. Network analysis indicated that module hubs and network hubs of bacterial communities were both rare taxa. VIF (variance inflation factor) and RDA (redundancy analysis) showed temperature, ammonia and nitrate were the most important factors affecting bacterial community function and composition. All results together indicate that Miseq high-throughput sequencing was an effective tool to explore changes in bacterial community structure during enrichment and domestication of heterotrophic nitrification-aerobic denitrification bacteria, which could in the future supply a reference to isolate "directional-accurate-efficient" microbial agents.