Evaluation of environmental factors and microbial community structure in an important drinking-water reservoir across seasons

Jie Feng; Letian Zhou; Xiaochao Zhao; Jianyi Chen; Zhi Li; Yongfeng Liu; Lei Ou; Zixin Xie; Miao Wang; Xue Yin; Xin Zhang; Yan Li; Mingjie Luo; Lidong Zeng; Qin Yan; Linshen Xie; Lei Sun

doi:10.3389/fmicb.2023.1091818

Evaluation of environmental factors and microbial community structure in an important drinking-water reservoir across seasons

Front Microbiol. 2023 Feb 14:14:1091818. doi: 10.3389/fmicb.2023.1091818. eCollection 2023.

Authors

Jie Feng¹, Letian Zhou², Xiaochao Zhao², Jianyi Chen¹, Zhi Li¹, Yongfeng Liu², Lei Ou¹, Zixin Xie¹, Miao Wang², Xue Yin¹, Xin Zhang², Yan Li², Mingjie Luo², Lidong Zeng², Qin Yan², Linshen Xie¹, Lei Sun²

Affiliations

¹ State Environmental Protection Key Laboratory of Drinking Water Source Management and Technology, Shenzhen Academy of Environmental Sciences, Shenzhen, China.
² GeneMind Biosciences Company Limited, Shenzhen, China.

Abstract

The composition of microbial communities varies in water and sediments, and changes in environmental factors have major effects on microbiomes. Here, we characterized variations in microbial communities and physicochemical factors at two sites in a large subtropical drinking water reservoir in southern China. The microbiomes of all sites, including the diversity and abundance of microbial species, were determined via metagenomics, and the relationships between microbiomes and physicochemical factors were determined via redundancy analysis. The dominant species in sediment and water samples differed; Dinobryon sp. LO226KS and Dinobryon divergens were dominant in sediment samples, whereas Candidatus Fonsibacter ubiquis and Microcystis elabens were dominant in water. The diversity was also significantly different in microbial alpha diversity between water and sediment habitats (p < 0.01). The trophic level index (TLI) was the major factor affecting the microbial community in water samples; Mycolicibacterium litorale and Mycolicibacterium phlei were significantly positively related to TLI. Furthermore, we also studied the distribution of algal toxin-encoding genes and antibiotic-resistant genes (ARGs) in the reservoir. It found that water samples contained more phycotoxin genes, with the cylindrospermopsin gene cluster most abundant. We found three genera highly related to cylindrospermopsin and explored a new cyanobacteria Aphanocapsa montana that may produce cylindrospermopsin based on the correlation through network analysis. The multidrug resistance gene was the most abundant ARG, while the relationship between ARGs and bacteria in sediment samples was more complicated than in water. The results of this study enhance our understanding of the effects of environmental factors on microbiomes. In conclusion, research on the properties, including profiles of algal toxin-encoding genes and ARGs, and microbial communities can aid water quality monitoring and conservation.

Keywords: cylindrospermopsins (CYNs); metagoenomics; multidrug resistance genes; subtropical drinking water source; trophic level index (TLI).