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Gao B, Hong J, Deng Q, Han B, Kong J, Zhang C. A novel sulfur supply strategy for maximizing lipid production in Tribonema minus (Xanthophyceae). BIORESOURCE TECHNOLOGY 2024; 394:130205. [PMID: 38104661 DOI: 10.1016/j.biortech.2023.130205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 12/11/2023] [Accepted: 12/12/2023] [Indexed: 12/19/2023]
Abstract
Tribonema minus, a promising filamentous oleaginous microalga, was cultured under different nutrient concentrations and different culture modes (fed-batch culture, two-step culture) to study the method of rapid regulation of its lipid metabolism. In contrast to many other oleaginous microalgae, T. minus did not show that nitrogen stress promoted lipid accumulation; however, sulfur deficiency promoted rapid lipid accumulation with a maximum lipid content of 54% of dry weight. Increasing the MgSO4 concentration significantly increased nitrogen uptake and biomass (10.09 g/L). Lipid productivity was significantly increased by the two-step culture using a medium with a high concentration of MgSO4 in the first step and a sulfur-free medium in the second step. In addition, it was found that the lipid content of T. minus was negatively correlated with the intracellular sulfur content when the intracellular sulfur content was below 0.6%. This study provides a new approach for industrial lipid production in T. minus.
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Affiliation(s)
- Baoyan Gao
- Department of Ecology, Research Center for Hydrobiology, Jinan University, Guangzhou 510632, People's Republic of China
| | - Jian Hong
- Department of Ecology, Research Center for Hydrobiology, Jinan University, Guangzhou 510632, People's Republic of China
| | - Qian Deng
- Department of Ecology, Research Center for Hydrobiology, Jinan University, Guangzhou 510632, People's Republic of China
| | - Baoye Han
- Department of Ecology, Research Center for Hydrobiology, Jinan University, Guangzhou 510632, People's Republic of China
| | - Jielin Kong
- Department of Ecology, Research Center for Hydrobiology, Jinan University, Guangzhou 510632, People's Republic of China
| | - Chengwu Zhang
- Department of Ecology, Research Center for Hydrobiology, Jinan University, Guangzhou 510632, People's Republic of China.
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Zhang X, Zhang Y, Chen Z, Gu P, Li X, Wang G. Exploring cell aggregation as a defense strategy against perchlorate stress in Chlamydomonas reinhardtii through multi-omics analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:167045. [PMID: 37709088 DOI: 10.1016/j.scitotenv.2023.167045] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 09/06/2023] [Accepted: 09/11/2023] [Indexed: 09/16/2023]
Abstract
Perchlorate (ClO4-) is a type of novel, widely distributed, and persistent inorganic pollutant. However, the impacts of perchlorate on freshwater algae remain unclear. In this study, the response and defense mechanisms of microalgae (Chlamydomonas reinhardtii) under perchlorate stress were investigated by integrating physiological and biochemical monitoring, transcriptomics, and metabolomics. Weighted gene co-expression network analysis (WGCNA) of transcriptome data was used to analyze the relationship between genes and phenotype and screen the key pathways. C. reinhardtii exhibited aggregate behavior when exposed to 100- and 200-mM perchlorate but was restored to its unicellular lifestyle when transferred to fresh medium. WGCNA results found that the "carbohydrate metabolism" and "lipid metabolism" pathways were closely related to cell aggregation phenotype. The differential expression genes (DEGs) and differentially accumulated metabolites (DAMs) of these pathways were upregulated, indicating that the lipid and carbohydrate metabolisms were enhanced in aggregated cells. Additionally, most genes and metabolites related to phytohormone abscisic acid (ABA) biosynthesis and the mitogen-activated protein kinase (MAPK) signaling pathway were significantly upregulated, indicating their crucial roles in the signal transmission of aggregated cells. Meanwhile, in aggregated cells, extracellular polymeric substances (EPS) and lipid contents increased, photosynthesis activity decreased, and the antioxidant system was activated. These characteristics contributed to C. reinhardtii's improved resistance to perchlorate stress. Above results demonstrated that cell aggregation behavior was the principal defense strategy of C. reinhardtii against perchlorate. Overall, this study sheds new light on the impact mechanisms of perchlorate to aquatic microalgae and provides multi-omics insights into the research of multicellular-like aggregation as an adaptation strategy to abiotic stress. These results are beneficial for assessing the risk of perchlorate in aquatic environments.
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Affiliation(s)
- Xianyuan Zhang
- Key Laboratory for Algae Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yixiao Zhang
- Key Laboratory for Algae Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; School of Science, Tibet University, Lasha 850000, China
| | - Zixu Chen
- Key Laboratory for Algae Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peifan Gu
- Key Laboratory for Algae Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoyan Li
- Key Laboratory for Algae Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
| | - Gaohong Wang
- Key Laboratory for Algae Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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