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Deng D, Meng H, Ma Y, Guo Y, Wang Z, He H, Xie W, Liu JE, Zhang L. The cumulative impact of temperature and nitrogen availability on the potential nitrogen fixation and extracellular polymeric substances secretion by Dolichospermum. HARMFUL ALGAE 2024; 135:102633. [PMID: 38830715 DOI: 10.1016/j.hal.2024.102633] [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: 01/24/2024] [Revised: 04/02/2024] [Accepted: 04/24/2024] [Indexed: 06/05/2024]
Abstract
Nitrogen-fixing cyanobacteria not only cause severe blooms but also play an important role in the nitrogen input processes of lakes. The production of extracellular polymeric substances (EPS) and the ability to fix nitrogen from the atmosphere provide nitrogen-fixing cyanobacteria with a competitive advantage over other organisms. Temperature and nitrogen availability are key environmental factors in regulating the growth of cyanobacteria. In this study, Dolichospermum (formerly known as Anabaena) was cultivated at three different temperatures (10 °C, 20 °C, and 30 °C) to examine the impact of temperature and nitrogen availability on nitrogen fixation capacity and the release of EPS. Initially, confocal laser scanning microscopy (CLSM) and the quantification of heterocysts at different temperatures revealed that lower temperatures (10 °C) hindered the differentiation of heterocysts under nitrogen-deprived conditions. Additionally, while heterocysts inhibited the photosynthetic activity of Dolichospermum, the secretion of EPS was notably affected by nitrogen limitation, particularly at 30 °C. Finally, real-time quantitative polymerase chain reaction (qPCR) was used to measure the expression of nitrogen-utilizing genes (ntcA and nifH) and EPS synthesis-related genes (wzb and wzc). The results indicated that under nitrogen-deprived conditions, the expression of each gene was upregulated, and there was a significant correlation between the upregulation of nitrogen-utilizing and EPS synthesis genes (P < 0.05). Our findings suggested that Dolichospermum responded to temperature variation by affecting the formation of heterocysts, impacting its potential nitrogen fixation capacity. Furthermore, the quantity of EPS released was more influenced by nitrogen availability than temperature. This research enhances our comprehension of interconnections between nitrogen deprivation and EPS production under the different temperatures.
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Affiliation(s)
- Dailan Deng
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing 210023, China
| | - Han Meng
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing 210023, China
| | - You Ma
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing 210023, China
| | - Yongqi Guo
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing 210023, China
| | - Zixuan Wang
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing 210023, China
| | - Huan He
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing 210023, China
| | - Wenming Xie
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing 210023, China
| | - Jin-E Liu
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing 210023, China.
| | - Limin Zhang
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Green Economy Development Institute, Nanjing University of Finance and Economics, Nanjing 210023, PR China
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Hu X, Luo Y, Man Y, Tang X, Bi Z, Ren L. Lipidomic and transcriptomic analysis reveals the self-regulation mechanism of Schizochytrium sp. in response to temperature stresses. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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