Document Type
Article
Publication Date
7-12-2022
Publication Title
mSystems
Volume
7
Issue
4
First page number:
1
Last page number:
16
Abstract
The compositional and physiological responses of autotrophic microbiotas to salinity in lakes remain unclear. In this study, the community composition and carbon fixation pathways of autotrophic microorganisms in lacustrine sediments with a salinity gradient (82.6 g/L to 0.54 g/L) were investigated by using metagenomic analysis. A total of 117 metagenome-assembled genomes (MAGs) with carbon fixation potentially belonging to 20 phyla were obtained. The abundance of these potential autotrophs increased significantly with decreasing salinity, and the variation of sediment autotrophic microbial communities was mainly affected by salinity, pH, and total organic carbon. Notably, along the decreasing salinity gradient, the dominant lineage shifted from Desulfobacterota to Proteobacteria. Meanwhile, the dominant carbon fixation pathway shifted from the Wood-Lungdahl pathway to the less-energy-efficient Calvin-Benson-Bassham cycle, with glycolysis shifting from the Embden-Meyerhof-Parnas pathway to the less-exergonic Entner-Doudoroff pathway. These results suggest that the physiological efficiency of autotrophic microorganisms decreased when the environmental salinity became lower. Metabolic inference of these MAGs revealed that carbon fixation may be coupled to the oxidation of reduced sulfur compounds and ferrous iron, dissimilatory nitrate reduction at low salinity, and dissimilatory sulfate reduction in hypersaline sediments. These results extend our understanding of metabolic versatility and niche diversity of autotrophic microorganisms in saline environments and shed light on the response of autotrophic microbiomes to salinity. These findings are of great significance for understanding the impact of desalination caused by climate warming on the carbon cycle of saline lake ecosystems.
Keywords
autotrophic microorganisms; salinity; genome-resolved metagenomics; carbon fixation pathway; saline lakes
Disciplines
Life Sciences
File Format
File Size
3100 KB
Language
English
Rights
IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Repository Citation
Fang, Y.,
Liu, J.,
Yang, J.,
Wu, G.,
Hua, Z.,
Dong, H.,
Hedlund, B. P.,
Baker, B. J.,
Jiang, H.
(2022).
Compositional and Metabolic Responses of Autotrophic Microbial Community to Salinity in Lacustrine Environments.
mSystems, 7(4),
1-16.
http://dx.doi.org/10.1128/msystems.00335-22
