Zhang Lei, Fang Shuqi, Hong Wenqing, Shen Zhen, Li Shuo, Fang Wangkai
School of Civil Engineering and Architecture, Chuzhou University, Chuzhou, 239000, China.
School of Civil Engineering and Architecture, Chuzhou University, Chuzhou, 239000, China.
Environ Res. 2023 Nov 1;236(Pt 2):116847. doi: 10.1016/j.envres.2023.116847. Epub 2023 Aug 7.
Pathogenic bacterial infections caused by water quality degradation are one of the most widespread environmental problems. Clarifying the structure of pathogens and their assembly mechanisms in lake ecosystems is vital to prevent the infestation of waterborne pathogens and maintain human health. However, the composition and assembly mechanisms of pathogenic bacterial communities in river and lake ecosystems are still poorly understood. In this study, we collected 17 water and 17 sediment samples from Lake Chaohu and its 11 inflow rivers. Sequencing of 16S rRNA genes was used to study bacterial pathogen communities. The results of the study showed that there was a significant difference (P < 0.05) in the composition of the pathogen community between riverine and lake habitats. Acinetobacter (36.49%) was the dominant bacterium in the river, whereas Flavobacterium (21.6%) was the most abundant bacterium in the lake. Deterministic processes (i.e., environmental filtering and species interaction) drove the assembly of pathogenic bacterial communities in the lake habitat, while stochastic processes shaped river pathogenic bacterial communities. Spearman correlation analysis showed that the α-diversity of bacterial communities was linearly and negatively linked to the relative abundance of pathogens. Having a higher bacterial community diversity had a suppressive effect on pathogen abundance. In addition, co-occurrence network analysis showed that bacterial communities were tightly linked to pathogenic bacteria. Pseudomonas aeruginosa and Salmonella enterica were identified as keystone species in an inflow water sampling network (W_FR), reducing the complexity of the network. These results provide a reference for assessments of water quality safety and pathogenic bacteria posing risks to human health in large freshwater lakes.
水质恶化导致的致病性细菌感染是最普遍的环境问题之一。阐明湖泊生态系统中病原体的结构及其组装机制对于预防水源性病原体的侵扰和维护人类健康至关重要。然而，河流和湖泊生态系统中致病细菌群落的组成和组装机制仍知之甚少。在本研究中，我们从巢湖及其11条入湖河流采集了17份水样和17份沉积物样本。利用16S rRNA基因测序研究细菌病原体群落。研究结果表明，河流和湖泊生境中病原体群落的组成存在显著差异（P < 0.05）。不动杆菌（36.49%）是河流中的优势菌，而黄杆菌（21.6%）是湖泊中最丰富的细菌。确定性过程（即环境过滤和物种相互作用）驱动了湖泊生境中致病细菌群落的组装，而随机过程塑造了河流致病细菌群落。Spearman相关性分析表明，细菌群落的α多样性与病原体的相对丰度呈线性负相关。具有较高的细菌群落多样性对病原体丰度有抑制作用。此外，共现网络分析表明，细菌群落与致病细菌紧密相连。铜绿假单胞菌和肠炎沙门氏菌被确定为入流水样网络（W_FR）中的关键物种，降低了网络的复杂性。这些结果为评估大型淡水湖水质安全和对人类健康构成风险的致病细菌提供了参考。
