Disentangling the drivers of Microcystis decomposition: Metabolic profile and co-occurrence of bacterial community

Shengnan Chen; Miaomiao Yan; Tinglin Huang; Hui Zhang; Kaiwen Liu; Xin Huang; Nan Li; Yutian Miao; Raju Sekar

doi:10.1016/j.scitotenv.2020.140062

Disentangling the drivers of Microcystis decomposition: Metabolic profile and co-occurrence of bacterial community

Sci Total Environ. 2020 Oct 15:739:140062. doi: 10.1016/j.scitotenv.2020.140062. Epub 2020 Jun 8.

Authors

Shengnan Chen¹, Miaomiao Yan², Tinglin Huang², Hui Zhang², Kaiwen Liu², Xin Huang², Nan Li², Yutian Miao², Raju Sekar³

Affiliations

¹ Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China. Electronic address: chenshengnan@xauat.edu.cn.
² Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
³ Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, China.

PMID: 32544693
DOI: 10.1016/j.scitotenv.2020.140062

Abstract

In aquatic ecosystems, water microbial communities can trigger the outbreak or decline of cyanobacterial blooms. However, the microbiological drivers of Microcystis decomposition in reservoirs remain unclear. Here, we explored the bacterial community metabolic profile and co-occurrence dynamics during Microcystis decomposition. The results showed that the decomposition of Microcystis greatly altered the metabolic characteristics and composition of the water bacterial community. Significant variations in bacterial community composition were observed: the bacterial community was mainly dominated by Proteobacteria, Actinobacteria, Planctomycetes, and Bacteroidetes during Microcystis decomposition. Additionally, members of Exiguobacterium, Rhodobacter, and Stenotrophomonas significantly increased during the terminal stages. Dissolved organic matters (DOM) primarily composed of fulvic-like, humic acid-like, and tryptophan-like components, which varied distinctly during Microcystis decomposition. Additionally, the metabolic activity of the bacterial community showed a continuous decrease during Microcystis decomposition. Functional prediction showed a sharp increase in the cell communication and sensory systems of the bacterial communities from day 12 to day 22. Co-occurrence networks showed that bacteria responded significantly to variations in the dynamics of Microcystis decomposition through close interactions between each other. Redundancy analysis (RDA) indicated that Chlorophyll a, nitrate nitrogen (NO₃^--N), dissolved oxygen (DO), and dissolved organic carbon (DOC) were crucial drivers for shaping the bacterial community structure. Taken together, these findings highlight the dynamics of the water bacterial community during Microcystis decomposition from the perspective of metabolism and community composition, however, further studies are needed to understand the algal degradation process associated with bacteria.

Keywords: Co-occurrence of bacterial community; Metabolic profile; Microcosm; Microcystis decomposition.

MeSH terms

Chlorophyll A
Metabolome
Microbiota*
Microcystis*
Nitrogen

Substances

Nitrogen
Chlorophyll A