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Wang Z, Tong S, Xu D, Huang X, Sun Y, Wang B, Sun H, Zhang X, Fan X, Wang W, Sun K, Wang Y, Zhang P, Gu Z, Ye N. Effects of temperature and nitrogen sources on physiological performance of the coccolithophore Emiliania huxleyi. MARINE ENVIRONMENTAL RESEARCH 2024; 196:106405. [PMID: 38368649 DOI: 10.1016/j.marenvres.2024.106405] [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: 12/10/2023] [Revised: 01/26/2024] [Accepted: 02/08/2024] [Indexed: 02/20/2024]
Abstract
Both temperature and nutrient levels are rising in worldwide ocean ecosystems, and they strongly influence biological responses of phytoplankton. However, few studies have addressed the interactive effects of temperature and nitrogen sources on physiological performance of the coccolithophore Emiliania huxleyi. In this study, we evaluated algal growth, photosynthesis and respiration, elemental composition, enzyme activity, and calcification under a matrix of two temperatures gradients (ambient temperature 20 °C and high temperature 24 °C) and two nitrogen sources (nitrate (NO3-) and ammonium (NH4+)). When the algae was cultured with NO3- medium, high temperature reduced algal photosynthesis and nitrate reductase activity, but it did not change other indicators significantly relative to ambient temperature. In addition, E. huxleyi preferred NO3- as the growth medium, whereas NH4+ had negative effects on physiological parameters. In the NH4+ medium, the growth rate, photosynthesis and photosynthetic rate, nitrate reductase activity, and particulate organic carbon and particulate organic nitrogen production rate of the algae decreased as temperature increased. Conversely, high temperature increased cellular particulate organic carbon, cellular particulate organic nitrogen, and particulate inorganic carbon levels. In summary, our findings indicate that the distribution and abundance of microalgae could be greatly affected under warming ocean temperature and different nutrient conditions.
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Affiliation(s)
- Zihao Wang
- Hainan University, College of Marine Biology and Fisheries, Haikou, Hainan, 570228, China; Hainan University, Sanya Nanfan Research Institute, Sanya, Hainan, 572000, China
| | - Shanying Tong
- College of Life Science, Ludong University, Yantai, China
| | - Dong Xu
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Xintong Huang
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Yanmin Sun
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Bingkun Wang
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Haoming Sun
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Xiaowen Zhang
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Xiao Fan
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Wei Wang
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Ke Sun
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Yitao Wang
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Pengyan Zhang
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China
| | - Zhifeng Gu
- Hainan University, College of Marine Biology and Fisheries, Haikou, Hainan, 570228, China; Hainan University, Sanya Nanfan Research Institute, Sanya, Hainan, 572000, China.
| | - Naihao Ye
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Laoshan Laboratory, Qingdao, Shandong, 266237, China.
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Wagner H, Schad A, Höhmann S, Briol TA, Wilhelm C. Carbon and energy balance of biotechnological glycolate production from microalgae in a pre-industrial scale flat panel photobioreactor. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:42. [PMID: 38486283 PMCID: PMC10941469 DOI: 10.1186/s13068-024-02479-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 02/15/2024] [Indexed: 03/17/2024]
Abstract
Glycolate is produced by microalgae under photorespiratory conditions and has the potential for sustainable organic carbon production in biotechnology. This study explores the glycolate production balance in Chlamydomonas reinhardtii, using a custom-built 10-L flat panel bioreactor with sophisticated measurements of process factors such as nutrient supply, gassing, light absorption and mass balances. As a result, detailed information regarding carbon and energy balance is obtained to support techno-economic analyses. It is shown how nitrogen is a crucial element in the biotechnological process and monitoring nitrogen content is vital for optimum performance. Moreover, the suitable reactor design is advantageous to efficiently adjust the gas composition. The oxygen content has to be slightly above 30% to induce photorespiration while maintaining photosynthetic efficiency. The final volume productivity reached 27.7 mg of glycolate per litre per hour, thus, the total process capacity can be calculated to 13 tonnes of glycolate per hectare per annum. The exceptional volume productivity of both biomass and glycolate production is demonstrated, and consequently can achieve a yearly CO2 sequestration rate of 35 tonnes per hectare. Although the system shows such high productivity, there are still opportunities to enhance the achieved volume productivity and thus exploit the biotechnological potential of glycolate production from microalgae.
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Affiliation(s)
- Heiko Wagner
- Department of Algal Biotechnology, Institute for Biology, University of Leipzig, Permoserstrasse 15, 04318, Leipzig, Germany.
| | - Antonia Schad
- Department of Algal Biotechnology, Institute for Biology, University of Leipzig, Permoserstrasse 15, 04318, Leipzig, Germany
| | - Sonja Höhmann
- Department of Solar Materials, Helmholtz Center for Environmental Research-UFZ, Permoserstrasse 15, 04318, Leipzig, Germany
| | - Tim Arik Briol
- Department of Solar Materials, Helmholtz Center for Environmental Research-UFZ, Permoserstrasse 15, 04318, Leipzig, Germany
| | - Christian Wilhelm
- Department of Algal Biotechnology, Institute for Biology, University of Leipzig, Permoserstrasse 15, 04318, Leipzig, Germany
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Liu H, Ni B, Duan A, He C, Zhang J. High Frankia abundance and low diversity of microbial community are associated with nodulation specificity and stability of sea buckthorn root nodule. FRONTIERS IN PLANT SCIENCE 2024; 15:1301447. [PMID: 38450407 PMCID: PMC10915256 DOI: 10.3389/fpls.2024.1301447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 02/05/2024] [Indexed: 03/08/2024]
Abstract
Introduction Actinorhizal symbioses are gaining attention due to the importance of symbiotic nitrogen fixation in sustainable agriculture. Sea buckthorn (Hippophae L.) is an important actinorhizal plant, yet research on the microbial community and nitrogen cycling in its nodules is limited. In addition, the influence of environmental differences on the microbial community of sea buckthorn nodules and whether there is a single nitrogen-fixing actinomycete species in the nodules are still unknown. Methods We investigated the diversity, community composition, network associations and nitrogen cycling pathways of the microbial communities in the root nodule (RN), nodule surface soil (NS), and bulk soil (BS) of Mongolian sea buckthorn distributed under three distinct ecological conditions in northern China using 16S rRNA gene and metagenomic sequencing. Combined with the data of environmental factors, the effects of environmental differences on different sample types were analyzed. Results The results showed that plants exerted a clear selective filtering effect on microbiota, resulting in a significant reduction in microbial community diversity and network complexity from BS to NS to RN. Proteobacteria was the most abundant phylum in the microbiomes of BS and NS. While RN was primarily dominated by Actinobacteria, with Frankia sp. EAN1pec serving as the most dominant species. Correlation analysis indicated that the host determined the microbial community composition in RN, independent of the ecological and geographical environmental changes of the sea buckthorn plantations. Nitrogen cycle pathway analyses showed that RN microbial community primarily functions in nitrogen fixation, and Frankia sp. EAN1pec was a major contributor to nitrogen fixation genes in RN. Discussion This study provides valuable insights into the effects of eco-geographical environment on the microbial communities of sea buckthorn RN. These findings further prove that the nodulation specificity and stability of sea buckthorn root and Frankia sp. EAN1pec may be the result of their long-term co-evolution.
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Affiliation(s)
- Hong Liu
- State Key Laboratory of Tree Genetics and Breeding & Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Bingbing Ni
- State Key Laboratory of Tree Genetics and Breeding & Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Aiguo Duan
- State Key Laboratory of Tree Genetics and Breeding & Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Caiyun He
- State Key Laboratory of Tree Genetics and Breeding & Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Jianguo Zhang
- State Key Laboratory of Tree Genetics and Breeding & Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
- Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
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Ruan Z, Lu M, Lin H, Chen S, Li P, Chen W, Xu H, Qiu D. Different photosynthetic responses of haploid and diploid Emiliania huxleyi (Prymnesiophyceae) to high light and ultraviolet radiation. BIORESOUR BIOPROCESS 2023; 10:40. [PMID: 38647570 PMCID: PMC10991182 DOI: 10.1186/s40643-023-00660-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 06/15/2023] [Indexed: 04/25/2024] Open
Abstract
Solar radiation varies quantitatively and qualitatively while penetrating through the seawater column and thus is one of the most important environmental factors shaping the vertical distribution pattern of phytoplankton. The haploid and diploid life-cycle phases of coccolithophores might have different vertical distribution preferences. Therefore, the two phases respond differently to high solar photosynthetically active radiation (PAR, 400-700 nm) and ultraviolet radiation (UVR, 280-400 nm). To test this, the haploid and diploid Emiliania huxleyi were exposed to oversaturating irradiance. In the presence of PAR alone, the effective quantum yield was reduced by 10% more due to the higher damage rate of photosystem II in haploid cells than in diploid cells. The addition of UVR resulted in further inhibition of the quantum yield for both haploid and diploid cells in the first 25 min, partly because of the increased damage of photosystem II. Intriguingly, this UVR-induced inhibition of the haploid cells completely recovered half an hour later. This recovery was confirmed by the comparable maximum quantum yields, maximum relative electron transport rates and yields of the haploid cells treated with PAR and PAR + UVR. Our data indicated that photosynthesis of the haploid phase was more sensitive to high visible light than the diploid phase but resistant to UVR-induced inhibition, reflecting the ecological niches to which this species adapts.
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Affiliation(s)
- Zuoxi Ruan
- STU-UNIVPM Joint Algal Research Center, Guangdong Provincial Key Laboratory of Marine Biotechnology, Marine Biology Institute, Shantou University, Shantou, 515063, Guangdong, China
| | - Meifang Lu
- STU-UNIVPM Joint Algal Research Center, Guangdong Provincial Key Laboratory of Marine Biotechnology, Marine Biology Institute, Shantou University, Shantou, 515063, Guangdong, China
| | - Hongmin Lin
- College of Pharmacy and Life Sciences, Jiujiang University, Jiujiang, 332005, Jiangxi, China
| | - Shanwen Chen
- STU-UNIVPM Joint Algal Research Center, Guangdong Provincial Key Laboratory of Marine Biotechnology, Marine Biology Institute, Shantou University, Shantou, 515063, Guangdong, China
| | - Ping Li
- STU-UNIVPM Joint Algal Research Center, Guangdong Provincial Key Laboratory of Marine Biotechnology, Marine Biology Institute, Shantou University, Shantou, 515063, Guangdong, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, Guangdong, China
| | - Weizhou Chen
- STU-UNIVPM Joint Algal Research Center, Guangdong Provincial Key Laboratory of Marine Biotechnology, Marine Biology Institute, Shantou University, Shantou, 515063, Guangdong, China
| | - Huijuan Xu
- CAS Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou, 510640, Guangdong, China.
| | - Dajun Qiu
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, Guangdong, China.
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Nagabalaji V, Maharaja P, Nishanthi R, Sathish G, Suthanthararajan R, Srinivasan SV. Effect of co-culturing bacteria and microalgae and influence of inoculum ratio during the biological treatment of tannery wastewater. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 341:118008. [PMID: 37146488 DOI: 10.1016/j.jenvman.2023.118008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/12/2023] [Accepted: 04/22/2023] [Indexed: 05/07/2023]
Abstract
This present investigation is carried out to study the effect of algal and bacterial inoculum concentrations on the removal of organic pollutants and nutrients from the tannery effluent by the combined symbiotic treatment process. The bacterial and microalgal consortia was developed in laboratory setup and mixed together to perform this study. The Influence of algae and bacteria inoculum concentrations on the removal of pollutants such as Chemical Oxygen Demand (COD) and Total Kjeldahl Nitrogen (TKN) were studied using statistical optimization through Response surface methodology. For the design of experimental set up and optimization, full factorial Central composite design was used. The profiles of pH, Dissolved Oxygen (DO) and nitrate were also monitored and studied. The inoculum concentrations of microalgae and bacteria showed significant effect on Co-culturing on COD, TKN and nitrate removals as major response. The linear effect of bacterial inoculum has positive dominant influence on COD and TKN removal efficiencies. Nitrate utilization by microalgae increases with the increase in microalgal inoculum concentration. The maximum removal efficiencies of COD and TKN with 89.9% and 80.9% were obtained at optimum bacterial and algal inoculum concentrations of 6.7 g/L and 8.0 g/L respectively. These outcomes of this study are immensely favorable for maximizing the COD and nitrogen (nutrients) removal capabilities of microalgae-bacterial consortia in tannery effluent.
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Affiliation(s)
- Velmurugan Nagabalaji
- Environmental Engineering Department, CSIR-Central Leather Research Institute, Chennai, 600 020, India; Academy of Scientific and Industrial Research (AcSIR), Ghaziabad, 201002, India.
| | - Pounsamy Maharaja
- Environmental Engineering Department, CSIR-Central Leather Research Institute, Chennai, 600 020, India
| | - Rajendiran Nishanthi
- Environmental Engineering Department, CSIR-Central Leather Research Institute, Chennai, 600 020, India
| | - Ganesan Sathish
- Environmental Engineering Department, CSIR-Central Leather Research Institute, Chennai, 600 020, India
| | | | - Shanmugham Venkatachalam Srinivasan
- Environmental Engineering Department, CSIR-Central Leather Research Institute, Chennai, 600 020, India; Academy of Scientific and Industrial Research (AcSIR), Ghaziabad, 201002, India.
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Genomics and degradation law of Acinetobacter junii in response to petroleum pollution. Process Biochem 2022. [DOI: 10.1016/j.procbio.2022.12.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Giordano M, Goodman CA, Huang F, Raven JA, Ruan Z. A mechanistic study of the influence of nitrogen and energy availability on the NH4+ sensitivity of nitrogen assimilation in Synechococcus. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:5596-5611. [PMID: 35595516 PMCID: PMC9467657 DOI: 10.1093/jxb/erac219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 05/19/2022] [Indexed: 05/23/2023]
Abstract
In most algae, NO3- assimilation is tightly controlled and is often inhibited by the presence of NH4+. In the marine, non-colonial, non-diazotrophic cyanobacterium Synechococcus UTEX 2380, NO3- assimilation is sensitive to NH4+ only when N does not limit growth. We sequenced the genome of Synechococcus UTEX 2380, studied the genetic organization of the nitrate assimilation related (NAR) genes, and investigated expression and kinetics of the main NAR enzymes, under N or light limitation. We found that Synechococcus UTEX 2380 is a β-cyanobacterium with a full complement of N uptake and assimilation genes and NAR regulatory elements. The nitrate reductase of our strain showed biphasic kinetics, previously observed only in freshwater or soil diazotrophic Synechococcus strains. Nitrite reductase and glutamine synthetase showed little response to our growth treatments, and their activity was usually much higher than that of nitrate reductase. NH4+ insensitivity of NAR genes may be associated with the stimulation of the binding of the regulator NtcA to NAR gene promoters by the high 2-oxoglutarate concentrations produced under N limitation. NH4+ sensitivity in energy-limited cells fits with the fact that, under these conditions, the use of NH4+ rather than NO3- decreases N-assimilation cost, whereas it would exacerbate N shortage under N limitation.
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Affiliation(s)
- Mario Giordano
- STU-UNIVPM Joint Algal Research Center, Marine Biology Institute, Shantou University, Shantou, Guangdong 515063, China
- Dipartimento di Scienze della Vita e dell’Ambiente, Università Politecnica delle Marche, Ancona 60131, Italy
- CMNS-Cell Biology and Molecular Genetics, 2107 Bioscience Research Building, University of Maryland, College Park, MD 20742-4407, USA
- Institute of Microbiology ASCR, Algatech, Trebon, Czech Republic
- National Research Council, Institute of Marine Science, Venezia, Italy
| | - Charles A Goodman
- CMNS-Cell Biology and Molecular Genetics, 2107 Bioscience Research Building, University of Maryland, College Park, MD 20742-4407, USA
| | - Fengying Huang
- STU-UNIVPM Joint Algal Research Center, Marine Biology Institute, Shantou University, Shantou, Guangdong 515063, China
| | - John A Raven
- Division of Plant Sciences, University of Dundee at the James Hutton Institute, Invergowrie, Dundee DD2 5 DA, UK
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Ultimo NSW 2007, Australia
- School of Biological Sciences, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
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Ma J, Wang P, Hu B, Wang X, Qian J. Synergistic promoting effect of increasing aquatic ammonium and CO 2 on Microcystis aeruginosa. CHEMOSPHERE 2022; 301:134553. [PMID: 35405194 DOI: 10.1016/j.chemosphere.2022.134553] [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: 11/11/2021] [Revised: 03/13/2022] [Accepted: 04/05/2022] [Indexed: 06/14/2023]
Abstract
Owing to climate change and intensive agricultural development, freshwater bodies have been affected by increases in both CO2 levels and chemically-reduced forms of N. However, little is known about how these changes affect cyanobacterial growth and blooms. This study explored a range of light conditions (30, 80, 130, or 200 μmol photons/m2/s) wherein Microcystis aeruginosa, a widespread bloom-forming species, was exposed to different concentrations of CO2 (400 parts per million (ppm) and 1000 ppm) in a medium containing NH4+ or NO3-. The interactive effects of N sources and CO2 levels on the C/N metabolic balance and energy balance were examined to assess changes in the growth of M. aeruginosa. When the light intensity was 80 μmol photons/m2/s, elevated CO2 could reduce intracellular reactive oxygen species (ROS) in NH4+-grown M. aeruginosa. Meanwhile, cell density and chlorophyll a (Chl a) increased with increasing CO2 levels, and the increase in Chl a was significantly greater in NH4+-grown M. aeruginosa than in NO3--grown M. aeruginosa. Under light conditions of 200 μmol photons/m2/s, elevated CO2 concentration caused NO3--grown M. aeruginosa to be affected by a large amount of ROS, and the growth of NO3--grown M. aeruginosa was finally suppressed. However, NH4+-grown M. aeruginosa had a smaller amount of ROS and showed improved growth as CO2 was elevated. This difference can be attributed to the faster metabolic pathways in the NH4+ environment, which manifested in a lower accumulation of 2-oxoglutarate and fatty acids as CO2 was elevated. These findings suggest that the simultaneous increase in ammonium and CO2 in aquatic ecosystems confers cyanobacteria with greater advantages than the combination of nitrate and CO2, which may aggravate cyanobacterial blooms.
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Affiliation(s)
- Jingjie Ma
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, People's Republic of China; College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Peifang Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, People's Republic of China; College of Environment, Hohai University, Nanjing, 210098, People's Republic of China.
| | - Bin Hu
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, People's Republic of China; College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Xun Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, People's Republic of China; College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Jin Qian
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, People's Republic of China; College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
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Ladrón de Guevara M, Maestre FT. Ecology and responses to climate change of biocrust-forming mosses in drylands. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:4380-4395. [PMID: 35553672 PMCID: PMC9291340 DOI: 10.1093/jxb/erac183] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
Interest in understanding the role of biocrusts as ecosystem engineers in drylands has substantially increased during the past two decades. Mosses are a major component of biocrusts and dominate their late successional stages. In general, their impacts on most ecosystem functions are greater than those of early-stage biocrust constituents. However, it is common to find contradictory results regarding how moss interactions with different biotic and abiotic factors affect ecosystem processes. This review aims to (i) describe the adaptations and environmental constraints of biocrust-forming mosses in drylands, (ii) identify their primary ecological roles in these ecosystems, and (iii) synthesize their responses to climate change. We emphasize the importance of interactions between specific functional traits of mosses (e.g. height, radiation reflectance, morphology, and shoot densities) and both the environment (e.g. climate, topography, and soil properties) and other organisms to understand their ecological roles and responses to climate change. We also highlight key areas that should be researched in the future to fill essential gaps in our understanding of the ecology and the responses to ongoing climate change of biocrust-forming mosses. These include a better understanding of intra- and interspecific interactions and mechanisms driving mosses' carbon balance during desiccation-rehydration cycles.
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Yang X, Bi Y, Ma X, Dong W, Wang X, Wang S. Transcriptomic analysis dissects the regulatory strategy of toxic cyanobacterium Microcystis aeruginosa under differential nitrogen forms. JOURNAL OF HAZARDOUS MATERIALS 2022; 428:128276. [PMID: 35051775 DOI: 10.1016/j.jhazmat.2022.128276] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 12/20/2021] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
The critical role of nitrogen in the global proliferation of cyanobacterial blooms is arousing increasing attention. However, the mechanism underlying the algal responses to differential nitrogen forms remains unclarified. The physiological and transcriptomic changes of Microcystis aeruginosa supplied with different nitrogen forms (nitrate and ammonium) were highlighted in this study. The results indicated that ammonium behaves better in stimulating the initial growth in N-limited cells than nitrate. However, a concomitant side effect is that cellular growth and photosynthesis decreased due to photosystem II damage induced by excess absorbed light energy under 10 mg L-1 ammonium. By contrast, adequate nitrate supply favored more efficient photosynthesis, higher biomass yield and microcystin quotas than ammonium. Depending on the supplied nitrogen form, different transcriptomic patterns were observed in M. aeruginosa. Under nitrate, the upregulation of genes involved in Arg biosynthesis, ornithine-urea cycle and photosynthesis increased nitrogen storage and cellular growth, while genes involved in cyclic electron flow around photosystem I and CO2-concentrating mechanism were heightened to dissipate excess energy under high ammonium. These insights provided important clues for understanding the physiological and molecular effects of available nitrogen forms on the frequent outbreaks of cyanobacteria.
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Affiliation(s)
- Xiaolong Yang
- School of Life Sciences, Nantong University, Nantong 226019, China; Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Yonghong Bi
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Xiaofei Ma
- School of Life Sciences, Nantong University, Nantong 226019, China
| | - Wei Dong
- School of Life Sciences, Nantong University, Nantong 226019, China
| | - Xun Wang
- School of Life Sciences, Nantong University, Nantong 226019, China
| | - Shoubing Wang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China.
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Heterologous Lactate Synthesis in Synechocystis sp. Strain PCC 6803 Causes a Growth Condition-Dependent Carbon Sink Effect. Appl Environ Microbiol 2022; 88:e0006322. [PMID: 35369703 PMCID: PMC9040622 DOI: 10.1128/aem.00063-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Cyanobacteria are considered promising hosts for product synthesis directly from CO2 via photosynthetic carbon assimilation. The introduction of heterologous carbon sinks in terms of product synthesis has been reported to induce the so-called “carbon sink effect,” described as the release of unused photosynthetic capacity by the introduction of additional carbon. This effect is thought to arise from a limitation of carbon metabolism that represents a bottleneck in carbon and electron flow, thus enforcing a downregulation of photosynthetic efficiency. It is not known so far how the cellular source/sink balance under different growth conditions influences the extent of the carbon sink effect and in turn product formation from CO2, constituting a heterologous carbon sink. We compared the Synechocystis sp. strain PCC 6803 wild type (WT) with an engineered lactate-producing strain (SAA023) in defined metabolic states. Unexpectedly, high-light conditions combined with carbon limitation enabled additional carbon assimilation for lactate production without affecting biomass formation. Thus, a strong carbon sink effect only was observed under carbon and thus sink limitation, but not under high-sink conditions. We show that the carbon sink effect was accompanied by an increased rate of alternative electron flow (AEF). Thus, AEF plays a crucial role in the equilibration of source/sink imbalances, presumably via ATP/NADPH balancing. This study emphasizes that the evaluation of the biotechnological potential of cyanobacteria profits from cultivation approaches enabling the establishment of defined metabolic states and respective quantitative analytics. Factors stimulating photosynthesis and carbon fixation are discussed. IMPORTANCE Previous studies reported various and differing effects of the heterologous production of carbon-based molecules on photosynthetic and growth efficiency of cyanobacteria. The typically applied cultivation in batch mode, with continuously changing growth conditions, however, precludes a clear differentiation between the impact of cultivation conditions on cell physiology and effects related to the specific nature of the product and its synthesis pathway. In this study, we employed a continuous cultivation system to maintain defined source/sink conditions and thus metabolic states. This allowed a systematic and quantitative analysis of the effect of NADPH-consuming lactate production on photosynthetic and growth efficiency. This approach enables a realistic evaluation of the biotechnological potential of engineered cyanobacterial strains. For example, the quantum requirement for carbon production was found to constitute an excellent indicator of the source/sink balance and thus a key parameter for photobioprocess optimization. Such knowledge is fundamental for rational and efficient strain and process development.
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Haberle I, Hrustić E, Petrić I, Pritišanac E, Šilović T, Magić L, Geček S, Budiša A, Blažina M. Adriatic cyanobacteria potential for cogeneration biofuel production with oil refinery wastewater remediation. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101978] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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13
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Sánchez-España J, Falagán C, Ayala D, Wendt-Potthoff K. Adaptation of Coccomyxa sp. to Extremely Low Light Conditions Causes Deep Chlorophyll and Oxygen Maxima in Acidic Pit Lakes. Microorganisms 2020; 8:E1218. [PMID: 32796657 PMCID: PMC7465793 DOI: 10.3390/microorganisms8081218] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/03/2020] [Accepted: 08/09/2020] [Indexed: 01/28/2023] Open
Abstract
Deep chlorophyll maxima (DCM) and metalimnetic oxygen maxima (MOM) are outstanding biogeochemical features of acidic pit lakes (APL). However, knowledge of the eukaryotic phototrophs responsible for their formation is limited. We aimed at linking the dynamics of phototrophic communities inhabiting meromictic APL in Spain with the formation of these characteristic layers. Firstly, the dynamics of DCM and MOM and their relation to physico-chemical parameters (photosynthetically active radiation (PAR), pH, dissolved ferric iron concentration, temperature), pigments and nutrient distribution is described; secondly, the phototrophic community composition is studied through a combination of microscopy, biomolecular and "omics" tools. Phototrophic communities of the studied APL show a low diversity dominated by green microalgae, specifically Coccomyxa sp., which have been successfully adapted to the chemically harsh conditions. DCM and MOM are usually non-coincident. DCM correspond to layers where phototrophs have higher chlorophyll content per cell to cope with extremely low PAR (<1 µmol m-2 s-1), but where photosynthetic oxygen production is limited. MOM correspond to shallower waters with more light, higher phytoplankton biomass and intense photosynthetic activity, which affects both oxygen concentration and water temperature. The main drivers of DCM formation in these APL are likely the need for nutrient uptake and photo-acclimation.
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Affiliation(s)
- Javier Sánchez-España
- Spanish Geological Survey, Geochemistry and Sustainable Mining Unit, Calera 1, Tres Cantos, 28760 Madrid, Spain
| | - Carmen Falagán
- Environmental and Sustainability Institute and Camborne School of Mines, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE, UK;
| | - Diana Ayala
- Department of Civil and Environmental Engineering, The Pennsylvania State University, 212 Sackett Building, University Park, PA 16802, USA;
| | - Katrin Wendt-Potthoff
- Helmholtz Centre for Environmental Research—UFZ, Brückstraße 3a, 39114 Magdeburg, Germany;
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14
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Venuleo M, Giordano M. Different Nutritional Histories Affect the Susceptibility of Algae to Grazing. JOURNAL OF PHYCOLOGY 2019; 55:997-1010. [PMID: 31309551 DOI: 10.1111/jpy.12901] [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: 11/20/2018] [Accepted: 06/11/2019] [Indexed: 06/10/2023]
Abstract
We hypothesize that algae with different cell compositions are differently perceived by their predators and consequently subjected to selective grazing. Five populations of the diatom Phaeodactylum tricornutum that differed in organic and elemental composition, but were otherwise identical, were generated by acclimation to distinct growth regimes. The different populations were then mixed in pairs and subjected to predation by either the rotifer Brachionus plicatilis or the copepod Acartia tonsa. The presence of rotifers had no impact on the ratio between any two algal populations. The presence of copepods, however, affected the ratio between algae previously acclimated to a medium containing 1 mM NH4+ and algae acclimated to 0.5 mM NO3- , and to either a lower irradiance or a higher CO2 concentration. We discuss the possible reason for the influence of different nutritional histories on the vulnerability of algae to predators. The differential impact of grazers on the growth of algae with different nutritional histories may result from direct selective grazing (i.e., grazers can detect algae with the most palatable cell composition), alone or combined to an asymmetric utilization of the nutrients regenerated after predation by co-existing algal populations. Our results strongly suggest that the nutritional history of algae can influence the relationships between phytoplankton and grazers and hint at the possibility that algal cell composition is potentially subject to natural selection, because it influences the probability that algae survive predation.
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Affiliation(s)
- Marianna Venuleo
- Laboratory of Algal and Plant Physiology, Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, via Brecce Bianche, 60131, Ancona, Italy
| | - Mario Giordano
- Laboratory of Algal and Plant Physiology, Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, via Brecce Bianche, 60131, Ancona, Italy
- STU-UNIVPM Joint Algal Research Center, Marine Biology Institute, College of Sciences, Shantou University, Shantou, Guangdong, 515063, China
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Algatech, Trebon, Czech Republic
- National Research Council, Institute of Marine Science ISMAR, Venezia, Italy
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15
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The effect of light quality and quantity on carbon allocation in Chromera velia. Folia Microbiol (Praha) 2019; 64:655-662. [PMID: 31399911 DOI: 10.1007/s12223-019-00734-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 07/15/2019] [Indexed: 10/26/2022]
Abstract
Chromera velia is a marine photosynthetic relative of human apicomplexan parasites. It has been isolated from coral reefs and is indicted for being involved in symbioses with hermatypic corals. C. velia has been subject to intensive research, but still very little is known of its response to light quality and quantity. Here, we have studied the growth and compositional responses of C. velia to culture under monochromatic light (blue, green or red), at two photon flux densities (PFD, 20 and 100 μmol photons m-2 s-1). Our results show that C. velia growth rate is unaffected by the quality of light, whereas it responds to PFD. However, light quality influenced cell size, which was smaller for cells exposed to blue monochromatic light, regardless of PFD. PFD strongly influenced carbon allocation: at 20 μmol photons m-2 s-1, carbon was mainly allocated into proteins while at 100 μmol photons m-2 s-1, carbon was allocated mainly into carbohydrate and lipid pools. The blue light treatment caused a decrease in the lipids and carbohydrates to proteins and thus suggested to affect nitrogen metabolism in acclimated cells. Whole-cell absorption spectra revealed the existence of red-shifted chlorophyll a antenna not only under red light but in all low PFD treatments. These findings show the ability of C. velia to successfully adapt and thrive in spectrally very different environments of coral reefs.
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16
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Lachmann SC, Mettler‐Altmann T, Wacker A, Spijkerman E. Nitrate or ammonium: Influences of nitrogen source on the physiology of a green alga. Ecol Evol 2019; 9:1070-1082. [PMID: 30805141 PMCID: PMC6374670 DOI: 10.1002/ece3.4790] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 10/19/2018] [Accepted: 10/30/2018] [Indexed: 11/25/2022] Open
Abstract
In freshwaters, algal species are exposed to different inorganic nitrogen (Ni) sources whose incorporation varies in biochemical energy demand. We hypothesized that due to the lesser energy requirement of ammonium ( NH 4 + )-use, in contrast to nitrate ( NO 3 - )-use, more energy remains for other metabolic processes, especially under CO2- and phosphorus (Pi) limiting conditions. Therefore, we tested differences in cell characteristics of the green alga Chlamydomonas acidophila grown on NH 4 + or NO 3 - under covariation of CO2 and Pi-supply in order to determine limitations, in a full-factorial design. As expected, results revealed higher carbon fixation rates for NH 4 + -grown cells compared to growth with NO 3 - under low CO2 conditions. NO 3 - -grown cells accumulated more of the nine analyzed amino acids, especially under Pi-limited conditions, compared to cells provided with NH 4 + . This is probably due to a slower protein synthesis in cells provided with NO 3 - . In contrast to our expectations, compared to NH 4 + -grown cells NO 3 - -grown cells had higher photosynthetic efficiency under Pi-limitation. In conclusion, growth on the Ni-source NH 4 + did not result in a clearly enhanced Ci-assimilation, as it was highly dependent on Pi and CO2 conditions (replete or limited). Results are potentially connected to the fact that C. acidophila is able to use only CO2 as its inorganic carbon (Ci) source.
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Affiliation(s)
| | - Tabea Mettler‐Altmann
- Cluster of Excellence on Plant Sciences and Institute of Plant BiochemistryHeinrich‐Heine UniversityDüsseldorfGermany
| | - Alexander Wacker
- Heisenberg‐Group: Theoretical Aquatic Ecology and Ecophysiology, Institute of Biochemistry and BiologyUniversity of PotsdamPotsdamGermany
| | - Elly Spijkerman
- Institute of Biochemistry and BiologyUniversity of PotsdamPotsdamGermany
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17
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Wang J, Zhou W, Chen H, Zhan J, He C, Wang Q. Ammonium Nitrogen Tolerant Chlorella Strain Screening and Its Damaging Effects on Photosynthesis. Front Microbiol 2019; 9:3250. [PMID: 30666245 PMCID: PMC6330332 DOI: 10.3389/fmicb.2018.03250] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 12/14/2018] [Indexed: 11/13/2022] Open
Abstract
Nitrogen is an essential nutrient element. Ammonium nitrogen, one of the most common nitrogen sources, is found in various habitats, especially wastewater. However, excessive amounts of ammonium nitrogen can be toxic to phytoplankton, higher plants, fish, and other animals, and microorganisms. In this study, we explored the tolerance of green algae to ammonium nitrogen using 10 Chlorella strains. High concentrations of ammonium nitrogen directly inhibited the growth of Chlorella, but the degree of inhibition varied by strain. With the EC50 of 1.6 and 0.4 g L-1, FACHB-1563 and FACHB-1216, respectively had the highest and lowest tolerance to ammonium nitrogen among all strains tested, suggesting that FACHB-1563 could potentially be used to remove excess ammonium nitrogen from wastewater in bioremediation efforts. Two strains with the highest and lowest tolerance to ammonium nitrogen were selected to further explore the inhibitory effect of ammonium nitrogen on Chlorella. Analysis of chlorophyll fluorescence, oxygen evolution, and photosynthesis proteins via immunoblot showed that photosystem II (PSII) had been damaged when exposed to high levels of ammonium nitrogen, with the oxygen-evolving complex as the primary site, and electron transport fromQ A - to QB was subsequently inhibited by this treatment. A working model of ammonium nitrogen competition between N assimilation and PSII damage is proposed to elucidate that the assimilation rate of ammonium nitrogen by algae strains determines the tolerance of cells to ammonium nitrogen toxicity.
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Affiliation(s)
- Jie Wang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Wei Zhou
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Hui Chen
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Jiao Zhan
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Chenliu He
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Qiang Wang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of the Chinese Academy of Sciences, Beijing, China
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Shanthi G, Premalatha M, Anantharaman N. Effects of l-amino acids as organic nitrogen source on the growth rate, biochemical composition and polyphenol content of Spirulina platensis. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.09.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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19
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Tong S, Gao K, Hutchins DA. Adaptive evolution in the coccolithophore Gephyrocapsa oceanica following 1,000 generations of selection under elevated CO 2. GLOBAL CHANGE BIOLOGY 2018; 24:3055-3064. [PMID: 29356310 DOI: 10.1111/gcb.14065] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 12/05/2017] [Accepted: 01/12/2018] [Indexed: 06/07/2023]
Abstract
Coccolithophores are important oceanic primary producers not only in terms of photosynthesis but also because they produce calcite plates called coccoliths. Ongoing ocean acidification associated with changing seawater carbonate chemistry may impair calcification and other metabolic functions in coccolithophores. While short-term ocean acidification effects on calcification and other properties have been examined in a variety of coccolithophore species, long-term adaptive responses have scarcely been documented, other than for the single species Emiliania huxleyi. Here, we investigated the effects of ocean acidification on another ecologically important coccolithophore species, Gephyrocapsa oceanica, following 1,000 generations of growth under elevated CO2 conditions (1,000 μatm). High CO2 -selected populations exhibited reduced growth rates and enhanced particulate organic carbon (POC) and nitrogen (PON) production, relative to populations selected under ambient CO2 (400 μatm). Particulate inorganic carbon (PIC) and PIC/POC ratios decreased progressively throughout the selection period in high CO2 -selected cell lines. All of these trait changes persisted when high CO2 -grown populations were moved back to ambient CO2 conditions for about 10 generations. The results suggest that the calcification of some coccolithophores may be more heavily impaired by ocean acidification than previously predicted based on short-term studies, with potentially large implications for the ocean's carbon cycle under accelerating anthropogenic influences.
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Affiliation(s)
- Shanying Tong
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Kunshan Gao
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - David A Hutchins
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
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20
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Ruan Z, Raven JA, Giordano M. In Synechococcus sp. competition for energy between assimilation and acquisition of C and those of N only occurs when growth is light limited. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3829-3839. [PMID: 28369501 DOI: 10.1093/jxb/erx074] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The carbon-concentrating mechanisms (CCMs) of cyanobacteria counteract the low CO2 affinity and CO2:O2 selectivities of the Rubisco of these photolithotrophs and the relatively low oceanic CO2 availability. CCMs have a significant energy cost; if light is limiting, the use of N sources whose assimilation demands less energy could permit a greater investment of energy into CCMs and inorganic C (Ci) assimilation. To test this, we cultured Synechococcus sp. UTEX LB 2380 under either N or energy limitation, in the presence of NO3- or NH4+. When growth was energy-limited, NH4+-grown cells had a 1.2-fold higher growth rate, 1.3-fold higher dissolved inorganic carbon (DIC)-saturated photosynthetic rate, 19% higher linear electron transfer, 80% higher photosynthetic 1/K1/2(DIC), 2.0-fold greater slope of the linear part of the photosynthesis versus DIC curve, 3.5-fold larger intracellular Ci pool, and 2.3-fold higher Zn quota than NO3--grown cells. When energy was not limiting growth, there were not differences between NH4+- and NO3--grown cells, except for higher linear electron transfer and larger intracellular Ci pool.We conclude that, when energy limits growth, cells that use the cheaper N source divert energy from N assimilation to C acquisition and assimilation; this does not happen when energy is not limiting.
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Affiliation(s)
- Zuoxi Ruan
- Marine Biology Institute, Science Center, Shantou University, Shantou, Guangdong 515063, China
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona 60131, Italy
| | - John A Raven
- Division of Plant Sciences, University of Dundee at the James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Ultimo NSW 2007, Australia
| | - Mario Giordano
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona 60131, Italy
- Institute of Microbiology ASCR, Algatech, Trebon, Czech Republic
- National Research Council, Institute of Marine Science, Venezia, Italy
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