Xia Yu, Wang Xiaohui, Wen Xianghua, Ding Kun, Zhou Jizhong, Yang Yunfeng, Zhang Yu
Environmental Simulation and Pollution Control State Key Joint Laboratory, School of Environment, Tsinghua University, 100084, Beijing, People's Republic of China.
Appl Microbiol Biotechnol. 2014 Aug;98(16):7233-42. doi: 10.1007/s00253-014-5791-7. Epub 2014 May 10.
Understanding microbial community composition is thought to be crucial for improving process functioning and stabilities of full-scale activated sludge reactors in wastewater treatment plants (WWTPs). However, functional gene compositions of microbial communities within them have not been clearly elucidated. To gain a complete picture of microbial community, in this study, GeoChip 4.2 was used to profile the overall functional genes of three full-scale activated sludge bioreactors, the 16S rRNA gene diversities of which had been unveiled by 454-pyrosequencing in our previous investigation. Triplicate activated sludge samples from each system were analyzed, with the detection of 38,507 to 40,654 functional genes. A high similarity of 77.3-81.2 % shared functional genes was noted among the nine samples, verified by the high 16S rRNA gene similarity with shared operational taxonomic units (OTUs) constituting 66.4-70.0 % of the detected sequences in each system. Correlation analyses showed that the abundances of a wide array of functional genes were associated with system performances. For example, the abundances of carbon degradation genes were strongly correlated to chemical oxygen demand (COD) removal efficiencies (r = 0.8697, P < 0.01). Lastly, we found that sludge retention time (SRT), influent total nitrogen concentrations (TN inf), and dissolved oxygen (DO) concentrations were key environmental factors shaping the overall functional genes. Together, the results revealed vast functional gene diversity and some links between the functional gene compositions and microbe-mediated processes.
了解微生物群落组成被认为对于提高污水处理厂（WWTPs）中全尺寸活性污泥反应器的工艺功能和稳定性至关重要。然而，其中微生物群落的功能基因组成尚未得到明确阐释。为了全面了解微生物群落，在本研究中，使用GeoChip 4.2对三个全尺寸活性污泥生物反应器的整体功能基因进行了分析，在我们之前的调查中，已通过454焦磷酸测序揭示了它们的16S rRNA基因多样性。对每个系统的三份活性污泥样品进行了分析，检测到38,507至40,654个功能基因。九个样品中共有功能基因的相似度高达77.3 - 81.2%，这通过16S rRNA基因与共有操作分类单元（OTUs）的高度相似性得到了验证，每个系统中共有OTUs占检测序列的66.4 - 70.0%。相关性分析表明，大量功能基因的丰度与系统性能相关。例如，碳降解基因的丰度与化学需氧量（COD）去除效率密切相关（r = 0.8697，P < 0.01）。最后，我们发现污泥停留时间（SRT）、进水总氮浓度（TN inf）和溶解氧（DO）浓度是塑造整体功能基因的关键环境因素。总之，结果揭示了巨大的功能基因多样性以及功能基因组成与微生物介导过程之间的一些联系。
