Impact of planktonic low nucleic acid-content bacteria to bacterial community structure and associated ecological functions in a shallow lake

• Published in: The Science of the total environment Vol. 658; pp. 868 - 878
• Main Authors: Song, Yuhao, Wang, Yufeng, Mao, Guannan, Gao, Guanghai, Wang, Yingying
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 25.03.2019
• Subjects: 16S rRNA amplicon sequencing; Flow cytometric fingerprint; Low nucleic acid- content bacteria; Potential functions; Structural diversity; Structural diversity; Potential functions; Low nucleic acid- content bacteria; Flow cytometric fingerprint; 16S rRNA amplicon sequencing
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2018.12.274

In this study, 0.45 μm filtration, flow cytometric fingerprint, 16S rRNA amplicon sequencing, and bioinformation tools were adopted to analyze the structural diversity and potential functions of planktonic low nucleic acid (LNA)- content bacteria in a shallow lake. Three bacterial groups, namely, “LNA,” “high nucleic acid (HNA)-Small,” and “HNA-Large,” were classified through flow cytometric fingerprint, among which the “HNA-Small” group was possibly in the proliferation stage of the “LNA” group. Total nitrogen and phosphate were the key factors that influence the growth of LNA bacteria. Results of 16S rRNA amplicon sequencing showed that LNA bacteria were phylogenetically less diverse than HNA bacteria, and Actinobacteria and Proteobacteria (especially Gamma-Proteobacteria) were the dominant phyla in LNA bacterial operational taxonomic units (OTUs). Accordingly, hgcI_clade and Pseudomonas were the most abundant bacterial genera in LNA bacterial OTUs. The fraction of low-abundance LNA bacteria was sensitive to several environmental factors, indicating that environmental factors only determined the fraction distribution of low-abundance bacteria. The prediction of metabolic and ecological functions showed that LNA and HNA bacteria had distinct metabolic and ecological functions, which were mainly attributed to the dominant and exclusive bacterial groups. [Display omitted] •Small low nucleic acid content bacteria are dominant bacterial group in this lake.•Actinobacteria and Proteobacteria are dominant phyla within LNA bacteria.•Hgcl_clade and Pseudomonas are dominant genera within LNA bacteria.•Several environmental factors affect the growth and structure of LNA bacteria.•Dominant and exclusive bacteria determine the potential functions in this lake.