活性污泥法中微生物密度依赖性病毒动态及温和噬菌体的低活性

Microbial density-dependent viral dynamics and low activity of temperate phages in the activated sludge process.

作者信息

Liu Ruyin, Li Zong, Han Ganghua, Cun Shujuan, Hou Deyin, Yu Zhisheng, Xue Kai, Liu Xinchun

机构信息

College of Resources and Environment, University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing 100049, China; RCEES-IMCAS-UCAS Joint-Lab of Microbial Technology for Environmental Science, University of Chinese Academy of Sciences, Beijing, China; Yanshan Earth Critical Zone National Research Station, University of Chinese Academy of Sciences, Beijing, China; Binzhou Institute of Technology, Weiqiao-UCAS Science and Technology Park, Binzhou City, Shandong Province, China.

出版信息

Water Res. 2023 Apr 1;232:119709. doi: 10.1016/j.watres.2023.119709. Epub 2023 Feb 5.

DOI:10.1016/j.watres.2023.119709

PMID:36764107

Abstract

The ecological behavior of bacteriophages (phages), the most abundant biological entity in wastewater treatment systems, is poorly understood, especially that of temperate phages. Here, the temporal dynamics of lytic and temperate phages in a laboratory-scale activated sludge reactor with a sludge bulking issue was investigated using coupled sludge metagenomic and viromic analyses. The lysogenic fragments (prophages) identified were widely distributed in the reconstructed metagenome-assembled genomes (61.7%, n = 227). However, only 12.3% of the identified prophages experienced lysogenic-lytic switching, and the abundance contribution of prophages to free virus communities was only 0.02-0.3%, indicating low activity of temperate phages. Although the sludge community changed dramatically during reactor operation, no massive prophage induction events were detected. Statistical analyses showed strong correlations between sludge concentration and free virus and temperate phage communities, suggesting microbial density-dependent virus dynamics in the sludge microbiota.

摘要

噬菌体是废水处理系统中最为丰富的生物实体，其生态行为，尤其是温和噬菌体的生态行为，目前仍知之甚少。在此，我们利用污泥宏基因组和病毒组耦合分析方法，研究了一个存在污泥膨胀问题的实验室规模活性污泥反应器中烈性噬菌体和温和噬菌体的时间动态变化。鉴定出的溶原片段（前噬菌体）广泛分布于重构的宏基因组组装基因组中（61.7%，n = 227）。然而，仅12.3%的已鉴定前噬菌体经历了溶原 - 裂解转换，且前噬菌体对游离病毒群落的丰度贡献仅为0.02 - 0.3%，这表明温和噬菌体的活性较低。尽管在反应器运行期间污泥群落发生了显著变化，但未检测到大规模的前噬菌体诱导事件。统计分析表明，污泥浓度与游离病毒及温和噬菌体群落之间存在强相关性，这表明污泥微生物群中存在微生物密度依赖性的病毒动态变化。