Bacterial communities play crucial roles in the biogeochemical cycle of the surface sediments of freshwater lakes, but previous studies on bacterial community changes in this habitat have mostly been based on the total bacterial community (DNA level), while an exploration of the active microbiota at the RNA level has been lacking. Herein, we analysed the bacterial communities in the surface sediments of Lake Taihu at the DNA and RNA levels. Using MiSeq sequencing and real-time quantification, we found that the sequencing and quantitative results obtained at the RNA level compared with the DNA level were more accurate in responding to the spatiotemporal dynamic changes of the bacterial community. Although both sequencing methods indicated that Proteobacteria, Chloroflexi, Acidobacteria, Nitrospirae, Bacteroidetes and Actinobacteria were the dominant phyla, the co-occurrence network at the RNA level could better reflect the close relationship between microorganisms in the surface sediment. Additionally, further analysis showed that Prochlorococcus and Microcystis were the most relevant and dominant genera of Cyanobacteria in the total and active bacterial communities, respectively; our results also demonstrated that the analysis of Cyanobacteria-related groups at the RNA level was more 'informative'.

中文翻译：

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太湖表层沉积物中总细菌和活性细菌群落的比较分析。

细菌群落在淡水湖表面沉积物的生物地球化学循环中起着至关重要的作用，但是先前关于该栖息地细菌群落变化的研究主要基于总细菌群落（DNA水平），而在该细菌群落中探索活跃的微生物群。 RNA水平一直缺乏。在这里，我们分析了太湖表层沉积物中DNA和RNA水平的细菌群落。使用MiSeq测序和实时定量分析，我们发现在RNA水平上获得的测序和定量结果与DNA水平相比，在响应细菌群落的时空动态变化方面更为准确。尽管两种测序方法都表明，变形杆菌，绿弯曲菌，酸性细菌，硝化螺旋菌，拟杆菌属和放线菌是主要的菌种，在RNA水平上的共现网络可以更好地反映表面沉积物中微生物之间的紧密关系。此外，进一步的分析表明，原绿球菌和微囊藻分别是蓝细菌在总细菌和活跃细菌群落中最相关和最主要的属。我们的结果还表明，在RNA水平上对蓝细菌相关基团的分析更具“参考价值”。