Morphological, transcriptional, and metabolic analyses of osmotic-adapted mechanisms of the halophilic Aspergillus montevidensis ZYD4 under hypersaline conditions
Halophilic fungi in hypersaline habitats require multiple cellular responses for high-salinity adaptation. However, the exact mechanisms behind these adaptation processes remain to be slightly known. The current study is aimed at elucidating the morphological, transcriptomic, and metabolomic changes of the halophilic fungus Aspergillus montevidensis ZYD4 under hypersaline conditions. Under these conditions, the fungus promoted conidia formation and suppressed cleistothecium development. Furthermore, the fungus differentially expressed genes (P < 0.0001) that controlled ion transport, amino acid transport and metabolism, soluble sugar accumulation, fatty acid β-oxidation, saturated fatty acid synthesis, electron transfer, and oxidative stress tolerance. Additionally, the hypersalinized mycelia widely accumulated metabolites, including amino acids, soluble sugars, saturated fatty acids, and other carbon- and nitrogen-containing compounds. The addition of metabolites—such as neohesperidin, biuret, aspartic acid, alanine, proline, and ornithine—significantly promoted the growth (P ≤ 0.05) and the morphological adaptations of A. montevidensis ZYD4 grown in hypersaline environments. Our study demonstrated that morphological shifts, ion equilibrium, carbon and nitrogen metabolism for solute accumulation, and energy production are vital to halophilic fungi so that they can build tolerance to high-salinity environments.
KeywordsTranscriptome Metabolome Halophilic fungus Aspergillus montevidensis Hypersaline adaptation Carbon and nitrogen metabolism
We are especially grateful to the editor and reviewers for their valuable comments on the manuscript. The manuscript was linguistically edited by Natalie Kaplan, Johns Hopkins University and by Long Lynette, Dartmouth College.
This work was supported by the National Natural Science Foundation of China (no. 31100017) and by the Program of Agricultural Scientific and Technological Innovation of Shaanxi Province (2018NY-156).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflicts of interest.
This article does not contain any studies performed with human participants or with animals by the author.
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