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Nam G, An G, Na J, Jung J. Control of Microcystis aeruginosa by Daphnia: Experimental evidence and identification of involved infochemicals. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 352:124144. [PMID: 38735459 DOI: 10.1016/j.envpol.2024.124144] [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: 03/09/2024] [Revised: 05/08/2024] [Accepted: 05/09/2024] [Indexed: 05/14/2024]
Abstract
Infochemicals refer to chemicals responsible for information exchange between organisms. We evaluated the effects of Daphnia magna and Daphnia galeata infochemicals on Microcystis aeruginosa for 15d. The Daphnia infochemicals were obtained from spent medium after culturing Daphnia in Elendt M4 medium for 48 h. Both Daphnia infochemicals significantly increased (p < 0.05) the intracellular reactive oxygen species level and microcystin-LR concentration in M. aeruginosa. This cellular effect increased colony formation of M. aeruginosa, thereby inhibiting the growth of M. aeruginosa. D. galeata infochemicals provoked significantly greater (p < 0.05) adverse effects on M. aeruginosa than those of D. magna infochemicals, which were further exaggerated by pre-exposure of Daphnia to M. aeruginosa. This result seems to be related to the different compositions and concentrations of Daphnia infochemicals. Several Daphnia infochemicals, such as methyl ferulate, cyclohexanone, 3, 5-dimethyl, hexanedioic acid, and bis(2-ethylhexyl) ester, showed a high correlation with M. aeruginosa cell concentration (|r | >0.6), suggesting that they may play a key role in controlling harmful cyanobacteria. Additionally, pre-exposure of D. magna and D. galeata to M. aeruginosa produced oleic acid, methyl ester, and n-hexadecanoic acid, with a highly correlation with M. aeruginosa cell concentration (|r | >0.6). p-tolyl acetate and linoleic acid were detected only in the pre-exposed D. galeata infochemicals. These findings suggest that some of Daphnia infochemicals identified in this study can be a promising tool to control M. aeruginosa growth. However, further studies are required to verify the specific actions of these infochemicals against cyanobacteria.
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Affiliation(s)
- Gwiwoong Nam
- OJeong Resilience Institute, Korea University, Seoul, 02841, Republic of Korea
| | - Gersan An
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Joorim Na
- OJeong Resilience Institute, Korea University, Seoul, 02841, Republic of Korea
| | - Jinho Jung
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea.
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Guo Z, Li J, Zhang Z. Meta-analysis for systematic review of global micro/nano-plastics contamination versus various freshwater microalgae: Toxicological effect patterns, taxon-specific response, and potential eco-risks. WATER RESEARCH 2024; 258:121706. [PMID: 38761590 DOI: 10.1016/j.watres.2024.121706] [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: 11/12/2023] [Revised: 04/18/2024] [Accepted: 04/30/2024] [Indexed: 05/20/2024]
Abstract
Micro/nano-plastics (MNPs), as emerging persistent pollutants, are threatening freshwater ecosystems worldwide. Microalgae are important primary producers at the base of trophic level and susceptible to MNPs contamination, possibly resulting in further contamination in higher trophic levels and water quality. This study conducted a systematic review of 1071 observations from 63 publications, utilizing meta-analysis and subgroup analysis to investigate the toxicological effect patterns of MNPs parameters (size, concentration, and type) on microalgae. We also explored the potential eco-risks of certain specific MNPs parameters and subtle variations in the response of various microalgae taxa to MNPs. Results suggested that microplastics significantly inhibited microalgal photosynthesis, while nano-plastics induced more severe cell membrane damage and promoted toxin-release. Within a certain range of concentrations (0∼50 mg/L), rising MNPs concentration progressively inhibited microalgal growth and chlorophyll-a content, and progressively enhanced toxin-release. Among MNPs types, polyamide caused higher growth inhibition and more severe lipid peroxidation, and polystyrene induced more toxin-release, whereas polyethylene terephthalate and polymethyl methacrylate posed minimal effects on microalgae. Moreover, Bacillariophyta growth was inhibited most significantly, while Chlorophyta displayed strong tolerance and Cyanophyta possessed strong adaptive and exceptional resilience. Particularly, Komvophoron, Microcystis, Nostoc, Scenedesmus, and Gomphonema were more tolerant and might dominate freshwater microalgal communities under MNPs contamination. These results are crucial for acquiring the fate of freshwater microalgae under various MNPs contamination, identifying dominant microalgae, and reasonably assessing and managing involved eco-risks.
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Affiliation(s)
- Zhonghui Guo
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China
| | - Jieming Li
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China.
| | - Ziqing Zhang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China
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Du L, Liu Q, Wang L, Lyu H, Tang J. Microplastics enhanced the allelopathy of pyrogallol on toxic Microcystis with additional risks: Microcystins release and greenhouse gases emissions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:173864. [PMID: 38879032 DOI: 10.1016/j.scitotenv.2024.173864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 05/16/2024] [Accepted: 06/07/2024] [Indexed: 06/21/2024]
Abstract
Cyanobacteria blooms (CBs) caused by eutrophication pose a global concern, especially Microcystis aeruginosa (M. aeruginosa), which could release harmful microcystins (MCs). The impact of microplastics (MPs) on allelopathy in freshwater environments is not well understood. This study examined the joint effect of adding polystyrene (PS-MPs) as representative MPs and two concentrations (2 and 8 mg/L) of pyrogallol (PYR) on the allelopathy of M. aeruginosa. The results showed that the addition of PS-MPs intensified the inhibitory effect of 8 mg/L PYR on the growth and photosynthesis of M. aeruginosa. After a 7-day incubation period, the cell density decreased to 69.7 %, and the chl-a content decreased to 48 % compared to the condition without PS-MPs (p < 0.05). Although the growth and photosynthesis of toxic Microcystis decreased with the addition of PS-MPs, the addition of PS-MPs significantly resulted in a 3.49-fold increase in intracellular MCs and a 1.10-fold increase in extracellular MCs (p < 0.05). Additionally, the emission rates of greenhouse gases (GHGs) (carbon dioxide, nitrous oxide and methane) increased by 2.66, 2.23 and 2.17-fold, respectively (p < 0.05). In addition, transcriptomic analysis showed that the addition of PS-MPs led to the dysregulation of gene expression related to DNA synthesis, membrane function, enzyme activity, stimulus detection, MCs release and GHGs emissions in M. aeruginosa. PYR and PS-MPs triggered ROS-induced membrane damage and disrupted photosynthesis in algae, leading to increased MCs and GHG emissions. PS-MPs accumulation exacerbated this issue by impeding light absorption and membrane function, further heightening the release of MCs and GHGs emissions. Therefore, PS-MPs exhibited a synergistic effect with PYR in inhibiting the growth and photosynthesis of M. aeruginosa, resulting in additional risks such as MCs release and GHGs emissions. These results provide valuable insights for the ecological risk assessment and control of algae bloom in freshwater ecosystems.
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Affiliation(s)
- Linqing Du
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education)/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Qinglong Liu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education)/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Lan Wang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education)/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Honghong Lyu
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China
| | - Jingchun Tang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education)/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
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Kwidzińska K, Zalewska M, Aksmann A, Kobos J, Mazur-Marzec H, Caban M. Multi-biomarker response of cyanobacteria Synechocystis salina and Microcystis aeruginosa to diclofenac. JOURNAL OF HAZARDOUS MATERIALS 2024; 471:134373. [PMID: 38678710 DOI: 10.1016/j.jhazmat.2024.134373] [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: 12/04/2023] [Revised: 02/14/2024] [Accepted: 04/19/2024] [Indexed: 05/01/2024]
Abstract
The cyanobacterial response to pharmaceuticals is less frequently investigated compared to green algae. Pharmaceuticals can influence not only the growth rate of cyanobacteria culture, but can also cause changes at the cellular level. The effect of diclofenac (DCF) as one of the for cyanobacteria has been rarely tested, and DCF has never been applied with cellular biomarkers. The aim of this work was to test the response of two unicellular cyanobacteria (Synechocystis salina and Microcystis aeruginosa) toward DCF (100 mg L-1) under photoautotrophic growth conditions. Such endpoints were analyzed as cells number, DCF uptake, the change in concentrations of photosynthetic pigments, the production of toxins, and chlorophyll a in vivo fluorescence. It was noted that during a 96 h exposure, cell proliferation was not impacted. Nevertheless, a biochemical response was observed. The increased production of microcystin was noted for M. aeruginosa. Due to the negligible absorption of DCF into cells, it is possible that the biochemical changes are induced by an external signal. The application of non-standard biomarkers demonstrates the effect of DCF on microorganism metabolism without a corresponding effect on biomass. The high resistance of cyanobacteria to DCF and the stimulating effect of DCF on the secretion of toxins raise concerns for environment biodiversity.
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Affiliation(s)
- Klaudia Kwidzińska
- University of Gdansk, Faculty of Chemistry, Department of Environmental Analysis, ul. Wita Stwosza 63, 80-308 Gdańsk, Poland.
| | - Martyna Zalewska
- University of Gdansk, Faculty of Biology, Department of Plant Experimental Biology and Biotechnology, ul. Wita Stwosza 59, 80-308 Gdańsk, Poland
| | - Anna Aksmann
- University of Gdansk, Faculty of Biology, Department of Plant Experimental Biology and Biotechnology, ul. Wita Stwosza 59, 80-308 Gdańsk, Poland
| | - Justyna Kobos
- University of Gdansk, Faculty of Oceanography and Geography, Department of Marine Biology and Biotechnology, al. Marszałka Piłsudskiego 46, 81-378 Gdynia, Poland
| | - Hanna Mazur-Marzec
- University of Gdansk, Faculty of Oceanography and Geography, Department of Marine Biology and Biotechnology, al. Marszałka Piłsudskiego 46, 81-378 Gdynia, Poland
| | - Magda Caban
- University of Gdansk, Faculty of Chemistry, Department of Environmental Analysis, ul. Wita Stwosza 63, 80-308 Gdańsk, Poland
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Guo Z, Zhang M, Li J. Modifying luteolin's algicidal effect on Microcystis by virgin and diversely-aged polystyrene microplastics: Unveiling novel mechanisms through microalgal adaptive strategies. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 356:124237. [PMID: 38801882 DOI: 10.1016/j.envpol.2024.124237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 05/23/2024] [Accepted: 05/25/2024] [Indexed: 05/29/2024]
Abstract
Luteolin has shown great potential in inhibiting Microcystis-dominated cyanobacterial blooms. However, widespread microplastics (MPs) in natural aquatic systems often serve as substrates for cyanobacterial growth, which could impact cyanobacterial resistance to external stresses and interfere with luteolin's algicidal effect. This study explored the influence of virgin and diversely-aged polystyrene microplastics (PS-MPs) on inhibitory effect of luteolin on Microcystis growth and its microcystins (MCs) production/release. Moreover, the underlying mechanisms were also revealed by jointly analyzing SEM image, antioxidant response, exopolymeric substances (EPSs) production, and functional gene expression. Results suggested that 0.5, 5, and 50 mg/L virgin and diversely-aged PS-MPs almost weakened growth inhibition and oxidative damage of two doses of luteolin against Microcystisby stimulating its EPSs production and inducing self-aggregation of Microcystis cells and/or hetero-aggregation between Microcystis cells and PS-MPs. Compared to virgin PS-MPs, photo-aged PS-MPs possessed rougher flaky surfaces, and hydrothermal-aged PS-MPs showed internal cracking. These characteristics led to greater stimulation of EPS production and exhibited more significant protective effects on Microcystis. Notably, PS-MPs also decreased MCs content in aqueous phase, likely because they adsorbed some MCs. Such toxigenic hetero-aggregates formed by MCs, MPs, and Microcystis cells would directly poison grazing organisms that consume them and create more pathways for MCs into food web, posing greater eco-risks. This is the first study to clarify the influence and mechanisms of virgin and diversely-aged MPs on allelopathic algicidal effects from the perspective of microalgal inherent adaptive strategies.
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Affiliation(s)
- Zhonghui Guo
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China
| | - Mingxia Zhang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China
| | - Jieming Li
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China.
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Xie Z, Nie Y, Dong M, Nie M, Tang J. Integrated physio-biochemical and transcriptomic analysis reveals the joint toxicity mechanisms of two typical antidepressants fluoxetine and sertraline on Microcystis aeruginosa. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171802. [PMID: 38508265 DOI: 10.1016/j.scitotenv.2024.171802] [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: 12/30/2023] [Revised: 02/20/2024] [Accepted: 03/16/2024] [Indexed: 03/22/2024]
Abstract
Selective serotonin reuptake inhibitor (SSRI) antidepressants are of increasing concern worldwide due to their ubiquitous occurrence and detrimental effects on aquatic organisms. However, little is known regarding their effects on the dominant bloom-forming cyanobacterium, Microcystis aeruginosa. Here, we investigated the individual and joint effects of two typical SSRIs fluoxetine (FLX) and sertraline (SER) on M. aeruginosa at physio-biochemical and molecular levels. Results showed that FLX and SER had strong growth inhibitory effects on M. aeruginosa with the 96-h median effect concentrations (EC50s) of 362 and 225 μg/L, respectively. Besides, the mixtures showed an additive effect on microalgal growth. Meanwhile, both individual SSRIs and their mixtures can inhibit photosynthetic pigment synthesis, cause oxidative damage, destroy cell membrane, and promote microcystin-leucine-arginine (MC-LR) synthesis and release. Moreover, the mixtures enhanced the damage to photosynthesis, antioxidant system, and cell membrane and facilitated MC-LR synthesis and release compared to individuals. Furthermore, transcriptomic analysis revealed that the dysregulation of the key genes related to transport, photosystem, protein synthesis, and non-ribosomal peptide structures was the fundamental molecular mechanism underlying the physio-biochemical responses of M. aeruginosa. These findings provide a better understanding of the toxicity mechanisms of SSRIs to microalgae and their risks to aquatic ecosystems.
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Affiliation(s)
- Zhengxin Xie
- School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Yunfan Nie
- School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Mingyue Dong
- School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Meng Nie
- School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Jun Tang
- School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China.
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Mugani R, El Khalloufi F, Redouane EM, Haida M, Aba RP, Essadki Y, El Amrani Zerrifi S, Hejjaj A, Ouazzani N, Campos A, Grossart HP, Mandi L, Vasconcelos V, Oudra B. Unlocking the potential of bacterioplankton-mediated microcystin degradation and removal: A bibliometric analysis of sustainable water treatment strategies. WATER RESEARCH 2024; 255:121497. [PMID: 38555787 DOI: 10.1016/j.watres.2024.121497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 01/31/2024] [Accepted: 03/19/2024] [Indexed: 04/02/2024]
Abstract
Microcystins (MCs) constitute a significant threat to human and environmental health, urging the development of effective removal methods for these toxins. In this review, we explore the potential of MC-degrading bacteria as a solution for the removal of MCs from water. The review insights into the mechanisms of action employed by these bacteria, elucidating their ability to degrade and thus remove MCs. After, the review points out the influence of the structural conformation of MCs on their removal, particularly their stability at different water depths within different water bodies. Then, we review the crucial role played by the production of MCs in ensuring the survival and safeguarding of the enzymatic activities of Microcystis cells. This justifies the need for developing effective and sustainable methods for removing MCs from aquatic ecosystems, given their critical ecological function and potential toxicity to humans and animals. Thereafter, challenges and limitations associated with using MC-degrading bacteria in water treatment are discussed, emphasizing the need for further research to optimize the selection of bacterial strains used for MCs biodegradation. The interaction of MCs-degrading bacteria with sediment particles is also crucial for their toxin removal potential and its efficiency. By presenting critical information, this review is a valuable resource for researchers, policymakers, and stakeholders involved in developing sustainable and practical approaches to remove MCs. Our review highlights the potential of various applications of MC-degrading bacteria, including multi-soil-layering (MSL) technologies. It emphasizes the need for ongoing research to optimize the utilization of MC-degrading bacteria in water treatment, ultimately ensuring the safety and quality of water sources. Moreover, this review highlights the value of bibliometric analyses in revealing research gaps and trends, providing detailed insights for further investigations. Specifically, we discuss the importance of employing advanced genomics, especially combining various OMICS approaches to identify and optimize the potential of MCs-degrading bacteria.
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Affiliation(s)
- Richard Mugani
- Water, Biodiversity and Climate Change Laboratory, Faculty of Sciences Semlalia, Cadi Ayyad University, Av. Prince My Abdellah, P.O. Box 2390, Marrakech 40000, Morocco; National Center for Studies and Research on Water and Energy, Cadi Ayyad University, P.O. Box: 511, 40000 Marrakech, Morocco; Department of Plankton and Microbial Ecology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Zur alten Fischerhuette 2, 14775 Stechlin, Germany
| | - Fatima El Khalloufi
- Natural Resources Engineering and Environmental Impacts Team, Multidisciplinary Research and Innovation Laboratory, Polydisciplinary Faculty of Khouribga, Sultan Moulay Slimane University of Beni Mellal, B.P.: 145, 25000, Khouribga, Morocco
| | - El Mahdi Redouane
- Water, Biodiversity and Climate Change Laboratory, Faculty of Sciences Semlalia, Cadi Ayyad University, Av. Prince My Abdellah, P.O. Box 2390, Marrakech 40000, Morocco
| | - Mohammed Haida
- Water, Biodiversity and Climate Change Laboratory, Faculty of Sciences Semlalia, Cadi Ayyad University, Av. Prince My Abdellah, P.O. Box 2390, Marrakech 40000, Morocco
| | - Roseline Prisca Aba
- Water, Biodiversity and Climate Change Laboratory, Faculty of Sciences Semlalia, Cadi Ayyad University, Av. Prince My Abdellah, P.O. Box 2390, Marrakech 40000, Morocco; National Center for Studies and Research on Water and Energy, Cadi Ayyad University, P.O. Box: 511, 40000 Marrakech, Morocco
| | - Yasser Essadki
- Water, Biodiversity and Climate Change Laboratory, Faculty of Sciences Semlalia, Cadi Ayyad University, Av. Prince My Abdellah, P.O. Box 2390, Marrakech 40000, Morocco
| | - Soukaina El Amrani Zerrifi
- Water, Biodiversity and Climate Change Laboratory, Faculty of Sciences Semlalia, Cadi Ayyad University, Av. Prince My Abdellah, P.O. Box 2390, Marrakech 40000, Morocco; Higher Institute of Nurses Professions and Health Techniques of Guelmim, Guelmim, Morocco
| | - Abdessamad Hejjaj
- National Center for Studies and Research on Water and Energy, Cadi Ayyad University, P.O. Box: 511, 40000 Marrakech, Morocco.
| | - Naaila Ouazzani
- Water, Biodiversity and Climate Change Laboratory, Faculty of Sciences Semlalia, Cadi Ayyad University, Av. Prince My Abdellah, P.O. Box 2390, Marrakech 40000, Morocco; National Center for Studies and Research on Water and Energy, Cadi Ayyad University, P.O. Box: 511, 40000 Marrakech, Morocco
| | - Alexandre Campos
- CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450-208 Porto, Portugal
| | - Hans-Peter Grossart
- Department of Plankton and Microbial Ecology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Zur alten Fischerhuette 2, 14775 Stechlin, Germany; Institute of Biochemistry and Biology, University of Potsdam, Maulbeeralle 2, 14469 Potsdam, Germany
| | - Laila Mandi
- Water, Biodiversity and Climate Change Laboratory, Faculty of Sciences Semlalia, Cadi Ayyad University, Av. Prince My Abdellah, P.O. Box 2390, Marrakech 40000, Morocco; National Center for Studies and Research on Water and Energy, Cadi Ayyad University, P.O. Box: 511, 40000 Marrakech, Morocco
| | - Vitor Vasconcelos
- CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450-208 Porto, Portugal; Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal.
| | - Brahim Oudra
- Water, Biodiversity and Climate Change Laboratory, Faculty of Sciences Semlalia, Cadi Ayyad University, Av. Prince My Abdellah, P.O. Box 2390, Marrakech 40000, Morocco
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Luo C, Chen C, Xian X, Cai WF, Yu X, Ye C. The secondary outbreak risk and mechanisms of Microcystis aeruginosa after H 2O 2 treatment. JOURNAL OF HAZARDOUS MATERIALS 2024; 470:134196. [PMID: 38603907 DOI: 10.1016/j.jhazmat.2024.134196] [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: 01/31/2024] [Revised: 03/18/2024] [Accepted: 03/31/2024] [Indexed: 04/13/2024]
Abstract
The secondary outbreak of cyanobacteria after algicide treatment has been a serious problem to water ecosystems. Hydrogen peroxide (H2O2) is an algaecide widely used in practice, but similar re-bloom problems are inevitably encountered. Our work found that Microcystis aeruginosa (M. aeruginosa) temporarily hibernates after H2O2 treatment, but there is still a risk of secondary outbreaks. Interestingly, the dormant period was as long as 20 and 28 days in 5 mg L-1 and 20 mg L-1 H2O2 treatment groups, respectively, but the photosynthetic activity was both restored much earlier (within 14 days). Subsequently, a quantitative imaging flow cytometry-based method was constructed and confirmed that the re-bloom had undergone two stages including first recovery and then re-division. The expression of ftsZ and fabZ genes showed that M. aeruginosa had active transcription processes related to cell division protein and fatty acid synthesis during the dormancy stat. Furthermore, metabolomics suggested that the recovery of M. aeruginosa was mainly by activating folate and salicylic acid synthesis pathways, which promoted environmental stress resistance, DNA synthesis, and cell membrane repair. This study reported the comprehensive mechanisms of secondary outbreak of M. aeruginosa after H2O2 treatment. The findings suggest that optimizing the dosage and frequency of H2O2, as well as exploring the potential use of salicylic acid and folic acid inhibitors, could be promising directions for future algal control strategies.
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Affiliation(s)
- Chen Luo
- Fujian Key Laboratory of Coastal Pollution Prevention and Control, College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Chenlan Chen
- Fujian Key Laboratory of Coastal Pollution Prevention and Control, College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Xuanxuan Xian
- Ecological &Environment Monitoring Center of Zhejiang Province, Hangzhou 310012, China
| | - Wei-Feng Cai
- Xiamen Cancer Center, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361103. China
| | - Xin Yu
- Fujian Key Laboratory of Coastal Pollution Prevention and Control, College of the Environment & Ecology, Xiamen University, Xiamen 361102, China.
| | - Chengsong Ye
- Fujian Key Laboratory of Coastal Pollution Prevention and Control, College of the Environment & Ecology, Xiamen University, Xiamen 361102, China.
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9
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Hancock TL, Dahedl EK, Kratz MA, Urakawa H. The synchronicity of bloom-forming cyanobacteria transcription patterns and hydrogen peroxide dynamics. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 348:123812. [PMID: 38527584 DOI: 10.1016/j.envpol.2024.123812] [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: 10/04/2023] [Revised: 03/08/2024] [Accepted: 03/15/2024] [Indexed: 03/27/2024]
Abstract
Hydrogen peroxide is a reactive oxygen species (ROS) naturally occurring at low levels in aquatic environments and production varies widely across different ecosystems. Oxygenic photosynthesis generates hydrogen peroxide as a byproduct, of which some portion can be released to ambient water. However, few studies have examined hydrogen peroxide dynamics in relation to cyanobacterial harmful algal blooms (cHABs). A year-long investigation of algal succession and hydrogen peroxide dynamics was conducted at the Caloosahatchee River, Florida, USA. We aimed to identify potential biological mechanisms responsible for elevated hydrogen peroxide production during cHAB events through the exploration of the freshwater microbial metatranscriptome. Hydrogen peroxide concentrations were elevated from February to September of 2021 when cyanobacteria were active and abundant. We observed one Microcystis cHAB event in spring and one in winter. Both had distinct nutrient uptake and cyanotoxin gene expression patterns. While meaningful levels of microcystin were only detected during periods of elevated hydrogen peroxide, cyanopeptolin was by far the most expressed cyanotoxin during the spring bloom when hydrogen peroxide was at its yearly maxima. Gene expressions of five microbial enzymes (Rubisco, superoxide dismutase, cytochrome b559, pyruvate oxidase, and NADH dehydrogenase) positively correlated to hydrogen peroxide concentrations. Additionally, there was higher nitrogen-fixing gene (nifDKH) expression by filamentous cyanobacteria after the spring bloom but no secondary bloom formation occurred. Overall, elevated environmental hydrogen peroxide concentrations were linked to cyanobacterial dominance and greater expression of specific enzymes in the photosynthesis of cyanobacteria. This implicates cyanobacterial photosynthesis and growth results in increased hydrogen peroxide generation as reflected in measured environmental concentrations.
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Affiliation(s)
- Taylor L Hancock
- School of Geosciences, University of South Florida, Tampa, FL, 33620, USA; Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, Florida, USA
| | - Elizabeth K Dahedl
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, Florida, USA
| | - Michael A Kratz
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, Florida, USA
| | - Hidetoshi Urakawa
- School of Geosciences, University of South Florida, Tampa, FL, 33620, USA; Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, Florida, USA.
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10
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Lefler FW, Barbosa M, Berthold DE, Roten R, Bishop WM, Laughinghouse HD. Microbial Community Response to Granular Peroxide-Based Algaecide Treatment of a Cyanobacterial Harmful Algal Bloom in Lake Okeechobee, Florida (USA). Toxins (Basel) 2024; 16:206. [PMID: 38787058 PMCID: PMC11125911 DOI: 10.3390/toxins16050206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/19/2024] [Accepted: 04/20/2024] [Indexed: 05/25/2024] Open
Abstract
Cyanobacterial harmful algal blooms (cyanoHABs) occur in fresh water globally. These can degrade water quality and produce toxins, resulting in ecological and economic damages. Thus, short-term management methods (i.e., algaecides) are necessary to rapidly mitigate the negative impacts of cyanoHABs. In this study, we assess the efficacy of a hydrogen peroxide-based algaecide (PAK® 27) on a Microcystis dominated bloom which occurred within the Pahokee Marina on Lake Okeechobee, Florida, USA. We observed a significant reduction in chlorophyll a (96.81%), phycocyanin (93.17%), and Microcystis cell counts (99.92%), and a substantial reduction in microcystins (86.7%) 48 h after treatment (HAT). Additionally, there was a significant shift in bacterial community structure 48 HAT, which coincided with an increase in the relative abundance of photosynthetic protists. These results indicate that hydrogen peroxide-based algaecides are an effective treatment method for cyanoHAB control and highlight their effects on non-target microorganisms (i.e., bacteria and protists).
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Affiliation(s)
- Forrest W. Lefler
- Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL 33314, USA; (F.W.L.); (M.B.); (D.E.B.)
| | - Maximiliano Barbosa
- Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL 33314, USA; (F.W.L.); (M.B.); (D.E.B.)
| | - David E. Berthold
- Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL 33314, USA; (F.W.L.); (M.B.); (D.E.B.)
| | - Rory Roten
- SePRO Research and Technology Campus, 16013 Watson Seed Farm Road, Whitakers, NC 27891, USA; (R.R.); (W.M.B.)
| | - West M. Bishop
- SePRO Research and Technology Campus, 16013 Watson Seed Farm Road, Whitakers, NC 27891, USA; (R.R.); (W.M.B.)
| | - H. Dail Laughinghouse
- Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL 33314, USA; (F.W.L.); (M.B.); (D.E.B.)
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11
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Reignier O, Bormans M, Hervé F, Robert E, Savar V, Tanniou S, Amzil Z, Noël C, Briand E. Spatio-temporal connectivity of a toxic cyanobacterial community and its associated microbiome along a freshwater-marine continuum. HARMFUL ALGAE 2024; 134:102627. [PMID: 38705620 DOI: 10.1016/j.hal.2024.102627] [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: 01/26/2024] [Revised: 03/22/2024] [Accepted: 04/10/2024] [Indexed: 05/07/2024]
Abstract
Due to climate changes and eutrophication, blooms of predominantly toxic freshwater cyanobacteria are intensifying and are likely to colonize estuaries, thus impacting benthic organisms and shellfish farming representing a major ecological, health and economic risk. In the natural environment, Microcystis form large mucilaginous colonies that influence the development of both cyanobacterial and embedded bacterial communities. However, little is known about the fate of natural colonies of Microcystis by salinity increase. In this study, we monitored the fate of a Microcystis dominated bloom and its microbiome along a French freshwater-marine gradient at different phases of a bloom. We demonstrated changes in the cyanobacterial genotypic composition, in the production of specific metabolites (toxins and compatible solutes) and in the heterotrophic bacteria structure in response to the salinity increase. In particular M. aeruginosa and M. wesenbergii survived salinities up to 20. Based on microcystin gene abundance, the cyanobacteria became more toxic during their estuarine transfer but with no selection of specific microcystin variants. An increase in compatible solutes occurred along the continuum with extensive trehalose and betaine accumulations. Salinity structured most the heterotrophic bacteria community, with an increased in the richness and diversity along the continuum. A core microbiome in the mucilage-associated attached fraction was highly abundant suggesting a strong interaction between Microcystis and its microbiome and a likely protecting role of the mucilage against an osmotic shock. These results underline the need to better determine the interactions between the Microcystis colonies and their microbiome as a likely key to their widespread success and adaptation to various environmental conditions.
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Affiliation(s)
| | - Myriam Bormans
- UMR CNRS 6553 ECOBIO, University of Rennes 1, Rennes F-35042, France
| | - Fabienne Hervé
- IFREMER, PHYTOX, Laboratoire METALG, Nantes F-44000, France
| | - Elise Robert
- IFREMER, PHYTOX, Laboratoire GENALG, Nantes F-44000, France
| | | | - Simon Tanniou
- IFREMER, PHYTOX, Laboratoire METALG, Nantes F-44000, France
| | - Zouher Amzil
- IFREMER, PHYTOX, Laboratoire METALG, Nantes F-44000, France
| | - Cyril Noël
- IFREMER, IRSI - Service de Bioinformatique (SeBiMER), Plouzané, France
| | - Enora Briand
- IFREMER, PHYTOX, Laboratoire GENALG, Nantes F-44000, France.
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12
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Li Z, Zheng Y, Ma H, Cui F. Microcystin-LR (MC-LR) inhibits green algae growth by regulating antioxidant and photosynthetic systems. HARMFUL ALGAE 2024; 134:102623. [PMID: 38705613 DOI: 10.1016/j.hal.2024.102623] [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: 09/07/2023] [Revised: 03/07/2024] [Accepted: 03/27/2024] [Indexed: 05/07/2024]
Abstract
Microcystins release from bloom-forming cyanobacteria is considered a way to gain competitive advantage in Microcystis populations, which threaten water resources security and aquatic ecological balance. However, the effects of microcystins on microalgae are still largely unclear. Through simulated culture experiments and the use of UHPLC-MS-based metabolomics, the effects of two microcystin-LR (MC-LR) concentrations (400 and 1,600 μg/L) on the growth and antioxidant properties of three algae species, the toxic Microcystis aeruginosa, a non-toxic Microcystis sp., and Chlorella vulgaris, were studied. The MC-LR caused damage to the photosynthetic system and activated the protective mechanism of the photosynthetic system by decreasing the chlorophyll-a and carotenoid concentrations. Microcystins triggered oxidative stress in C. vulgaris, which was the most sensitive algae species studied, and secreted more glycolipids into the extracellular compartment, thereby destroying its cell structure. However, C. vulgaris eliminated reactive oxygen species (ROS) by secreting terpenoids, thereby resisting oxidative stress. In addition, two metabolic pathways, the vitamin B6 and the sphingolipid pathways, of C. vulgaris were significantly disturbed by microcystins, contributing to cell membrane and mitochondrial damage. Thus, both the low (400 μg/L) and the high (1,600 μg/L) MC-LR concentration inhibited algae growth within 3 to 7 days, and the inhibition rates increased with the increase in the MC-LR concentration. The above results indicate that the toxin-producing Microcystis species have a stronger toxin tolerance under longer-term toxin exposure in natural water environments. Thus, microcystins participates in interspecific interaction and phytoplankton population regulation and creates suitable conditions for the toxin-producing M. aeruginosa to become the dominant species in algae blooms.
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Affiliation(s)
- Zhe Li
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
| | - Yun Zheng
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; CSCEC SCIMEE Sci. & Tech. Co., Ltd., Chengdu 610045, China
| | - Hua Ma
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China.
| | - Fuyi Cui
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
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13
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Hancock TL, Dahedl EK, Kratz MA, Urakawa H. Synechococcus dominance induced after hydrogen peroxide treatment of Microcystis bloom in the Caloosahatchee River, Florida. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 345:123508. [PMID: 38325511 DOI: 10.1016/j.envpol.2024.123508] [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: 12/22/2023] [Revised: 01/25/2024] [Accepted: 02/04/2024] [Indexed: 02/09/2024]
Abstract
Few field trials examining hydrogen peroxide as a cyanobacterial harmful algal bloom (cHAB) treatment have been conducted in subtropical and tropical regions. None have been tested in Florida, home to Lake Okeechobee and downstream waterways which periodically experience Microcystis bloom events. To investigate treatment effects in Florida, we applied a 490 μM (16.7 mg/L; 0.0015%) hydrogen peroxide spray to a minor bloom of Microcystis aeruginosa on the downstream side of Franklin Lock and Dam in the Caloosahatchee River. Although hydrogen peroxide decreased to background level one day post-treatment, succession was observed in phytoplankton community amplicon sequencing. The relative abundance of Microcystis decreased on day 3 by 86%, whereas the picocyanobacteria Synechococcus became dominant, increasing by 77% on day 3 and by 173% on day 14 to 57% of the phytoplankton community. Metatranscriptomics revealed Synechococcus likely benefitted from the antioxidant defense of upregulated peroxiredoxin, peroxidase/catalase, and rubrerythrin expressions immediately after treatment, and upregulated nitrate transport and urease to take advantage of available nitrogen. Our results indicated hydrogen peroxide induces succession of the phytoplankton community from Microcystis to non-toxic picocyanobacteria and could be used for selective suppression of harmful cyanobacteria.
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Affiliation(s)
- Taylor L Hancock
- School of Geosciences, University of South Florida, Tampa, FL, 33620, USA; Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL, USA
| | - Elizabeth K Dahedl
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL, USA
| | - Michael A Kratz
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL, USA
| | - Hidetoshi Urakawa
- School of Geosciences, University of South Florida, Tampa, FL, 33620, USA; Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL, USA.
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14
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Harris TD, Reinl KL, Azarderakhsh M, Berger SA, Berman MC, Bizic M, Bhattacharya R, Burnet SH, Cianci-Gaskill JA, Domis LNDS, Elfferich I, Ger KA, Grossart HPF, Ibelings BW, Ionescu D, Kouhanestani ZM, Mauch J, McElarney YR, Nava V, North RL, Ogashawara I, Paule-Mercado MCA, Soria-Píriz S, Sun X, Trout-Haney JV, Weyhenmeyer GA, Yokota K, Zhan Q. What makes a cyanobacterial bloom disappear? A review of the abiotic and biotic cyanobacterial bloom loss factors. HARMFUL ALGAE 2024; 133:102599. [PMID: 38485445 DOI: 10.1016/j.hal.2024.102599] [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: 11/10/2023] [Revised: 01/31/2024] [Accepted: 02/05/2024] [Indexed: 03/19/2024]
Abstract
Cyanobacterial blooms present substantial challenges to managers and threaten ecological and public health. Although the majority of cyanobacterial bloom research and management focuses on factors that control bloom initiation, duration, toxicity, and geographical extent, relatively little research focuses on the role of loss processes in blooms and how these processes are regulated. Here, we define a loss process in terms of population dynamics as any process that removes cells from a population, thereby decelerating or reducing the development and extent of blooms. We review abiotic (e.g., hydraulic flushing and oxidative stress/UV light) and biotic factors (e.g., allelopathic compounds, infections, grazing, and resting cells/programmed cell death) known to govern bloom loss. We found that the dominant loss processes depend on several system specific factors including cyanobacterial genera-specific traits, in situ physicochemical conditions, and the microbial, phytoplankton, and consumer community composition. We also address loss processes in the context of bloom management and discuss perspectives and challenges in predicting how a changing climate may directly and indirectly affect loss processes on blooms. A deeper understanding of bloom loss processes and their underlying mechanisms may help to mitigate the negative consequences of cyanobacterial blooms and improve current management strategies.
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Affiliation(s)
- Ted D Harris
- Kansas Biological Survey and Center for Ecological Research, University of Kansas, 2101 Constant Ave., Lawrence, KS, 66047
| | - Kaitlin L Reinl
- Lake Superior National Estuarine Research Reserve, University of Wisconsin - Madison Division of Extension, 14 Marina Dr, Superior, WI 54880
| | - Marzi Azarderakhsh
- Department of Construction and Civil Engineering, New York City College of Technology, 300 Jay Street, New York, NY 11201
| | - Stella A Berger
- Department of Plankton and Microbial Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Zur alten Fischerhütte 2, 16775 Stechlin, Germany
| | - Manuel Castro Berman
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180 and Darrin Freshwater Institute, Rensselaer Polytechnic Institute, Bolton Landing, NY, 12814
| | - Mina Bizic
- Department of Plankton and Microbial Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Zur alten Fischerhütte 2, 16775 Stechlin, Germany
| | - Ruchi Bhattacharya
- Department of Biological, Geological & Environmental Sciences, Cleveland State University, Cleveland, OH 44115
| | - Sarah H Burnet
- University of Idaho, Fish and Wildlife Sciences, Moscow, ID, USA, 83844
| | - Jacob A Cianci-Gaskill
- Old Woman Creek National Estuarine Research Reserve, Ohio Department of Natural Resources, 2514 Cleveland Rd East, Huron, OH 44839
| | - Lisette N de Senerpont Domis
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, 6708 PB Wageningen, The Netherlands; Department of Water Resources and Pervasive Systems Group, faculty of EEMCS and ITC, University of Twente, The Netherlands
| | - Inge Elfferich
- Cardiff University, Earth and Environmental Sciences, Main Building, Park Place CF10 3AT, Cardiff, UK
| | - K Ali Ger
- Department of Ecology, Center for Biosciences, Universidade Federal do Rio Grande do Norte, R. das Biociencias, Lagoa Nova, Natal, RN, 59078-970, Brazil
| | - Hans-Peter F Grossart
- Department of Plankton and Microbial Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Zur alten Fischerhütte 2, 16775 Stechlin, Germany; Potsdam University, Institute of Biochemistry and Biology, Maulbeeralle 2, 14469 Potsdam, Germany
| | - Bas W Ibelings
- Department F.-A. Forel for Environmental and Aquatic Sciences, University of Geneva, 66 Blvd Carl Vogt, 1205, Geneva, Switzerland
| | - Danny Ionescu
- Department of Plankton and Microbial Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Zur alten Fischerhütte 2, 16775 Stechlin, Germany
| | - Zohreh Mazaheri Kouhanestani
- School of Natural Resources, University of Missouri-Columbia, Anheuser-Busch Natural Resources Building, Columbia, MO, 65211-7220
| | - Jonas Mauch
- Department of Community and Ecosystem Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 301, 12587 Berlin, Germany
| | - Yvonne R McElarney
- Fisheries and Aquatic Ecosystems, Agri-Food and Biosciences Institute, Belfast, Northern Ireland
| | - Veronica Nava
- Department of Earth and Environmental Sciences, University of Milano-Bicocca, Piazza della Scienza 1, 20126 Milano, MI, Italy.
| | - Rebecca L North
- School of Natural Resources, University of Missouri-Columbia, Anheuser-Busch Natural Resources Building, Columbia, MO, 65211-7220
| | - Igor Ogashawara
- Department of Plankton and Microbial Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Zur alten Fischerhütte 2, 16775 Stechlin, Germany
| | - Ma Cristina A Paule-Mercado
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, Na Sádkách 7, České Budějovice 370 05, Czech Republic
| | - Sara Soria-Píriz
- Département des sciences biologiques, Université du Québec à Montréal, 141 Av. du Président-Kennedy, Montréal, QC H2 × 1Y4, Montréal, QC, Canada
| | - Xinyu Sun
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI 48824, USA
| | | | - Gesa A Weyhenmeyer
- Department of Ecology and Genetics/Limnology, Uppsala University, Norbyvägen 18D, 75236 Uppsala, Sweden
| | - Kiyoko Yokota
- Biology Department, State University of New York at Oneonta, Oneonta, NY 13820, USA
| | - Qing Zhan
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, 6708 PB Wageningen, The Netherlands
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15
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Piel T, Sandrini G, Weenink EFJ, Qin H, Herk MJV, Morales-Grooters ML, Schuurmans JM, Slot PC, Wijn G, Arntz J, Zervou SK, Kaloudis T, Hiskia A, Huisman J, Visser PM. Shifts in phytoplankton and zooplankton communities in three cyanobacteria-dominated lakes after treatment with hydrogen peroxide. HARMFUL ALGAE 2024; 133:102585. [PMID: 38485435 DOI: 10.1016/j.hal.2024.102585] [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: 10/03/2023] [Revised: 12/22/2023] [Accepted: 01/18/2024] [Indexed: 03/19/2024]
Abstract
Cyanobacteria can reach high densities in eutrophic lakes, which may cause problems due to their potential toxin production. Several methods are in use to prevent, control or mitigate harmful cyanobacterial blooms. Treatment of blooms with low concentrations of hydrogen peroxide (H2O2) is a promising emergency method. However, effects of H2O2 on cyanobacteria, eukaryotic phytoplankton and zooplankton have mainly been studied in controlled cultures and mesocosm experiments, while much less is known about the effectiveness and potential side effects of H2O2 treatments on entire lake ecosystems. In this study, we report on three different lakes in the Netherlands that were treated with average H2O2 concentrations ranging from 2 to 5 mg L-1 to suppress cyanobacterial blooms. Effects on phytoplankton and zooplankton communities, on cyanotoxin concentrations, and on nutrient availability in the lakes were assessed. After every H2O2 treatment, cyanobacteria drastically declined, sometimes by more than 99%, although blooms of Dolichospermum sp., Aphanizomenon sp., and Planktothrix rubescens were more strongly suppressed than a Planktothrix agardhii bloom. Eukaryotic phytoplankton were not significantly affected by the H2O2 additions and had an initial advantage over cyanobacteria after the treatment, when ample nutrients and light were available. In all three lakes, a new cyanobacterial bloom developed within several weeks after the first H2O2 treatment, and in two lakes a second H2O2 treatment was therefore applied to again suppress the cyanobacterial population. Rotifers strongly declined after most H2O2 treatments except when the H2O2 concentration was ≤ 2 mg L-1, whereas cladocerans were only mildly affected and copepods were least impacted by the added H2O2. In response to the treatments, the cyanotoxins microcystins and anabaenopeptins were released from the cells into the water column, but disappeared after a few days. We conclude that lake treatments with low concentrations of H2O2 can be a successful tool to suppress harmful cyanobacterial blooms, but may negatively affect some of the zooplankton taxa in lakes. We advise pre-tests prior to the treatment of lakes to define optimal treatment concentrations that kill the majority of the cyanobacteria and to minimize potential side effects on non-target organisms. In some cases, the pre-tests may discourage treatment of the lake.
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Affiliation(s)
- Tim Piel
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240,1090 GE Amsterdam, The Netherlands; Agendia NV, 1043 NT Amsterdam, The Netherlands
| | - Giovanni Sandrini
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240,1090 GE Amsterdam, The Netherlands; Department of Technology & Sources, Evides Water Company, 3006 AL Rotterdam, The Netherlands
| | - Erik F J Weenink
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240,1090 GE Amsterdam, The Netherlands
| | - Hongjie Qin
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240,1090 GE Amsterdam, The Netherlands; Guangdong Provincial Key Lab of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
| | - Maria J van Herk
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240,1090 GE Amsterdam, The Netherlands
| | - Mariël Léon Morales-Grooters
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240,1090 GE Amsterdam, The Netherlands; Department of Biomedical Engineering, Erasmus MC University Rotterdam, Office Ee2302, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands
| | - J Merijn Schuurmans
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240,1090 GE Amsterdam, The Netherlands
| | - Pieter C Slot
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240,1090 GE Amsterdam, The Netherlands
| | - Geert Wijn
- Arcadis Nederland B.V., P.O. Box 264, 6800 AG Arnhem, The Netherlands
| | - Jasper Arntz
- Arcadis Nederland B.V., P.O. Box 264, 6800 AG Arnhem, The Netherlands
| | - Sevasti-Kiriaki Zervou
- Photo-Catalytic Processes and Environmental Chemistry, Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research, "Demokritos", Patriarchou Gregoriou E & 27 Neapoleos Str, 15341 Athens, Greece
| | - Triantafyllos Kaloudis
- Photo-Catalytic Processes and Environmental Chemistry, Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research, "Demokritos", Patriarchou Gregoriou E & 27 Neapoleos Str, 15341 Athens, Greece; Laboratory of Organic Micropollutants, Water Quality Control Department, Athens Water Supply & Sewerage Company (EYDAP SA), Athens, Greece
| | - Anastasia Hiskia
- Photo-Catalytic Processes and Environmental Chemistry, Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research, "Demokritos", Patriarchou Gregoriou E & 27 Neapoleos Str, 15341 Athens, Greece
| | - Jef Huisman
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240,1090 GE Amsterdam, The Netherlands
| | - Petra M Visser
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240,1090 GE Amsterdam, The Netherlands
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16
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Jiang J, Zeng J, Wang J, Zuo J, Wei N, Song L, Shan K, Gan N. Changes in CO 2 concentration drive a succession of toxic and non-toxic strains of Microcystis blooms. WATER RESEARCH 2024; 250:121056. [PMID: 38171175 DOI: 10.1016/j.watres.2023.121056] [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: 09/25/2023] [Revised: 11/30/2023] [Accepted: 12/21/2023] [Indexed: 01/05/2024]
Abstract
The dynamic changes between toxic and non-toxic strains of Microcystis blooms have always been a hot topic. Previous studies have found that low CO2 favors toxic strains, but how changing dissolved CO2 (CO2 [aq]) in water body influences the succession of toxic and non-toxic strains in Microcystis blooms remains uncertain. Here, we combined laboratory competition experiments, field observations, and a machine learning model to reveal the links between CO2 changes and the succession. Laboratory experiments showed that under low CO2 conditions (100-150 ppm), the toxic strains could make better use of CO2 (aq) and be dominant. The non-toxic strains demonstrated a growth advantage as CO2 concentration increased (400-1000 ppm). Field observations from June to November in Lake Taihu showed that the percentage of toxic strains increased as CO2 (aq) decreased. Machine learning highlighted links between the inorganic carbon concentration and the proportion of advantageous strains. Our findings provide new insights for cyanoHABs prediction and prevention.
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Affiliation(s)
- Jingyu Jiang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China,; University of Chinese Academy of Sciences, Beijing, China
| | - Jiaying Zeng
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China,; University of Chinese Academy of Sciences, Beijing, China
| | - Jingkai Wang
- University of Chinese Academy of Sciences, Beijing, China,; Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Jun Zuo
- National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection, Institute for Eco-Environmental Research of Sanyang Wetland, Wenzhou University, Wenzhou 325035, China
| | - Nian Wei
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China
| | - Lirong Song
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China,; University of Chinese Academy of Sciences, Beijing, China
| | - Kun Shan
- University of Chinese Academy of Sciences, Beijing, China,; Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China,.
| | - Nanqin Gan
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China,; University of Chinese Academy of Sciences, Beijing, China,.
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17
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Romanis CS, Timms VJ, Nebauer DJ, Crosbie ND, Neilan BA. Microbiome analysis reveals Microcystis blooms endogenously seeded from benthos within wastewater maturation ponds. Appl Environ Microbiol 2024; 90:e0158523. [PMID: 38117057 PMCID: PMC10807444 DOI: 10.1128/aem.01585-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 10/27/2023] [Indexed: 12/21/2023] Open
Abstract
Toxigenic Microcystis blooms periodically disrupt the stabilization ponds of wastewater treatment plants (WWTPs). Dense proliferations of Microcystis cells within the surface waters (SWs) impede the water treatment process by reducing the treatment efficacy of the latent WWTP microbiome. Further, water quality is reduced when conventional treatment leads to Microcystis cell lysis and the release of intracellular microcystins into the water column. Recurrent seasonal Microcystis blooms cause significant financial burdens for the water industry and predicting their source is vital for bloom management strategies. We investigated the source of recurrent toxigenic Microcystis blooms at Australia's largest lagoon-based municipal WWTP in both sediment core (SC) and SW samples between 2018 and 2020. Bacterial community composition of the SC and SW samples according to 16S rRNA gene amplicon sequencing showed that Microcystis sp. was dominant within SW samples throughout the period and reached peak relative abundances (32%) during the summer. The same Microcystis Amplicon sequence variants were present within the SC and SW samples indicating a potential migratory population that transitions between the sediment water and SWs during bloom formation events. To investigate the potential of the sediment to act as a repository of viable Microcystis cells for recurrent bloom formation, a novel in-vitro bloom model was established featuring sediments and sterilized SW collected from the WWTP. Microcystin-producing Microcystis blooms were established through passive resuspension after 12 weeks of incubation. These results demonstrate the capacity of Microcystis to transition between the sediments and SWs in WWTPs, acting as a perennial inoculum for recurrent blooms.IMPORTANCECyanobacterial blooms are prevalent to wastewater treatment facilities owing to the stable, eutrophic conditions. Cyanobacterial proliferations can disrupt operational procedures through the blocking of filtration apparatus or altering the wastewater treatment plant (WWTP) microbiome, reducing treatment efficiency. Conventional wastewater treatment often results in the lysis of cyanobacterial cells and the release of intracellular toxins which pose a health risk to end users. This research identifies a potential seeding source of recurrent toxigenic cyanobacterial blooms within wastewater treatment facilities. Our results demonstrate the capacity of Microcystis to transition between the sediments and surface waters (SWs) of wastewater treatment ponds enabling water utilities to develop adequate monitoring and management strategies. Further, we developed a novel model to demonstrate benthic recruitment of toxigenic Microcystis under laboratory conditions facilitating future research into the genetic mechanisms behind bloom development.
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Affiliation(s)
- C. S. Romanis
- University of Newcastle, School of Environmental and Life Sciences, Callaghan, Australia
| | - V. J. Timms
- University of Newcastle, School of Environmental and Life Sciences, Callaghan, Australia
- ARC Centre of Excellence for Synthetic Biology, Callaghan, Australia
| | - D. J. Nebauer
- University of Newcastle, School of Environmental and Life Sciences, Callaghan, Australia
| | | | - B. A. Neilan
- University of Newcastle, School of Environmental and Life Sciences, Callaghan, Australia
- ARC Centre of Excellence for Synthetic Biology, Callaghan, Australia
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18
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Yan F, Li M, Zang S, Xu Z, Bao M, Wu H. UV radiation and temperature increase alter the PSII function and defense mechanisms in a bloom-forming cyanobacterium Microcystis aeruginosa. Front Microbiol 2024; 15:1351796. [PMID: 38292251 PMCID: PMC10825000 DOI: 10.3389/fmicb.2024.1351796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 01/04/2024] [Indexed: 02/01/2024] Open
Abstract
The aim was to determine the response of a bloom-forming Microcystis aeruginosa to climatic changes. Cultures of M. aeruginosa FACHB 905 were grown at two temperatures (25°C, 30°C) and exposed to high photosynthetically active radiation (PAR: 400-700 nm) alone or combined with UVR (PAR + UVR: 295-700 nm) for specified times. It was found that increased temperature enhanced M. aeruginosa sensitivity to both PAR and PAR + UVR as shown by reduced PSII quantum yields (Fv/Fm) in comparison with that at growth temperature (25°C), the presence of UVR significantly exacerbated the photoinhibition. M. aeruginosa cells grown at high temperature exhibited lower PSII repair rate (Krec) and sustained nonphotochemical quenching (NPQs) induction during the radiation exposure, particularly for PAR + UVR. Although high temperature alone or worked with UVR induced higher SOD and CAT activity and promoted the removal rate of PsbA, it seemed not enough to prevent the damage effect from them showing by the increased value of photoinactivation rate constant (Kpi). In addition, the energetic cost of microcystin synthesis at high temperature probably led to reduced materials and energy available for PsbA turnover, thus may partly account for the lower Krec and the declination of photosynthetic activity in cells following PAR and PAR + UVR exposure. Our findings suggest that increased temperature modulates the sensitivity of M. aeruginosa to UVR by affecting the PSII repair and defense capacity, thus influencing competitiveness and abundance in the future water environment.
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Affiliation(s)
- Fang Yan
- School of Life Science, Ludong University, Yantai, China
- Key Laboratory of Marine Biotechnology in Universities of Shandong, Ludong University, Yantai, China
| | - Mingze Li
- School of Life Science, Ludong University, Yantai, China
- Key Laboratory of Marine Biotechnology in Universities of Shandong, Ludong University, Yantai, China
| | - Shasha Zang
- School of Life Science, Ludong University, Yantai, China
- Key Laboratory of Marine Biotechnology in Universities of Shandong, Ludong University, Yantai, China
| | - Zhiguang Xu
- School of Life Science, Ludong University, Yantai, China
- Key Laboratory of Marine Biotechnology in Universities of Shandong, Ludong University, Yantai, China
| | - Menglin Bao
- School of Life Science, Ludong University, Yantai, China
- Key Laboratory of Marine Biotechnology in Universities of Shandong, Ludong University, Yantai, China
| | - Hongyan Wu
- School of Life Science, Ludong University, Yantai, China
- Key Laboratory of Marine Biotechnology in Universities of Shandong, Ludong University, Yantai, China
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19
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Zhang K, Gu Y, Cheng C, Xue Q, Xie L. Changes in microcystin concentration in Lake Taihu, 13 years (2007-2020) after the 2007 drinking water crisis. ENVIRONMENTAL RESEARCH 2024; 241:117597. [PMID: 37939808 DOI: 10.1016/j.envres.2023.117597] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 10/10/2023] [Accepted: 11/02/2023] [Indexed: 11/10/2023]
Abstract
Since the 2007 water crisis occurred in Lake Taihu, substantial measures have been taken to restore the lake. This study evaluates the effectiveness of these restoration activities. We examined the physicochemical parameters and the distribution of microcystin and Microcystis in both the water column and sediment during the bloom period of May 2020 to October 2020. The mean value of extracellular and intracellular microcystin content was 0.12 μg L-1 and 16.26 μg L-1, respectively. The mean value of microcystin in sediment was 172.02 ng g-1 and peaked in August. The concentration in the water and sediment was significantly lower than the historical average concentration. The abundance of toxigenic Microcystis and total Microcystis in the water column ranged from 2.61 × 102 to 2.25 × 109 copies·L-1 and 8.28 × 105 to 2.76 × 109 copies·L-1, respectively. The proportion of toxic Microcystis in the sediment ranging from 31.2% to 19.12%. The highest and lowest region was Meiliang Bay and Grass-algae type zone, respectively. The copy number of the 16S rRNA gene was 1-4 orders of magnitude higher than that of mcyA gene in populations of Microcystis, indicating that non-toxic Microcystis was the dominant form in the majority of the lake. The abundance of toxic Microcystis in the water column was positively correlated with total phosphorus, PO43--P and pH, while the water temperature played distinct role to the distribution of toxic Microcystis in sediment. Our research indicated phosphorus remains a key factor influencing the toxic Microcystis and microcystins in the water column. pH played distinct roles in the distribution of microcystins in sediment and water column. The increasing water temperature is a threat. Explicit management actions and policies, which take into account nutrient concentrations, pH, and increasing temperatures, are necessary to understand and control the distribution of microcystin and Microcystis in Lake Taihu.
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Affiliation(s)
- Kaiye Zhang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yurong Gu
- Kunshan Economic and Technological Development Zone Work Safety and Environmental Protection Bureau, Kunshan, 215300, China
| | - Chen Cheng
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qingju Xue
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
| | - Liqiang Xie
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China; School of Ecology and Environment, Anhui Normal University, Wuhu, Anhui, 241002, China.
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20
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Stark GF, Truchon AR, Dittmann E, Wilhelm SW. Closed circular genome sequence of a Microcystis aeruginosa PCC7806 Δ mcyB (UTK) non-toxic mutant. Microbiol Resour Announc 2023; 12:e0070023. [PMID: 37855595 PMCID: PMC10652910 DOI: 10.1128/mra.00700-23] [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: 08/01/2023] [Accepted: 09/14/2023] [Indexed: 10/20/2023] Open
Abstract
Here we report the complete, closed genome of the non-toxic Microcystis aeruginosa PCC7806 ΔmcyB mutant strain. This genome is 5,103,923 bp long, with a GC content of 42.07%. Compared to the published wild-type genome (Microcystis aeruginosa PCC7806SL), there is evidence of accumulated mutations beyond the inserted chloramphenicol resistance marker.
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Affiliation(s)
- Gwendolyn F. Stark
- Department of Microbiology, University of Tennessee Knoxville, Knoxville, Tennessee, USA
| | - Alexander R. Truchon
- Department of Microbiology, University of Tennessee Knoxville, Knoxville, Tennessee, USA
| | - Elke Dittmann
- Department of Microbiology, Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Steven W. Wilhelm
- Department of Microbiology, University of Tennessee Knoxville, Knoxville, Tennessee, USA
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21
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Guo Z, Li J, Luo D, Zhang M. Novel ecological implications of non-toxic Microcystis towards toxic ecotype in population-promoting toxic ecotype dominance at various N levels and cooperative defense against luteolin-stress. FEMS Microbiol Ecol 2023; 99:fiad138. [PMID: 37884453 DOI: 10.1093/femsec/fiad138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 09/26/2023] [Accepted: 10/25/2023] [Indexed: 10/28/2023] Open
Abstract
Microcystin (MC)-producing (MC+) and MC-free (MC-) Microcystis always co-exist and interact during Microcystis-dominated cyanobacterial blooms (MCBs), where MC+Microcystis abundance and extracellular MC-content (EMC) determine the hazard extent of MCBs. The current study elucidated intraspecific interaction between MC+ and MC-Microcystis at various nitrogen (N) levels (0.5-50 mg/L) and how such N-mediated interaction impacted algicidal and EMC-inhibiting effect of luteolin, a natural bioalgicide. Conclusively, MC+ and MC-Microcystis were inhibited mutually at N-limitation (0.5 mg/L), which enhanced the algicidal and EMC-inhibiting effects of luteolin. However, at N-sufficiency (5-50 mg/L), MC-Microcystis promoted MC+ ecotype growth and dominance, and such intraspecific interaction induced the cooperative defense of two ecotypes, weakening luteolin's algicidal and EMC-inhibiting effects. Mechanism analyses further revealed that MC+Microcystis in luteolin-stress co-culture secreted exopolymeric substances (EPSs) for self-protection against luteolin-stress and also released more EMC to induce EPS-production by MC-Microcystis as protectants, thus enhancing their luteolin-resistance and promoting their growth. This study provided novel ecological implications of MC-Microcystis toward MC+ ecotype in terms of assisting the dominant establishment of MC+Microcystis and cooperative defense with MC+ ecotype against luteolin, which guided the application of bioalgicide (i.e. luteolin) for MCBs and MCs pollution mitigation in different eutrophication-degree waters.
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Affiliation(s)
- Zhonghui Guo
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Jieming Li
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Di Luo
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Mingxia Zhang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
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22
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Li Z, Ma H, Hong Z, Zhang T, Cao M, Cui F, Grossart HP. Phytoplankton interspecific interactions modified by symbiotic fungi and bacterial metabolites under environmentally relevant hydrogen peroxide concentrations stress. WATER RESEARCH 2023; 246:120739. [PMID: 37844340 DOI: 10.1016/j.watres.2023.120739] [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: 07/29/2023] [Revised: 10/09/2023] [Accepted: 10/11/2023] [Indexed: 10/18/2023]
Abstract
Hydrogen peroxide (H2O2), which accumulates in water and triggers oxidative stress for aquatic microbes, has been shown to have profound impacts on planktonic microbial community dynamics including cyanobacterial bloom formation. Yet, potential effects of H2O2 on interspecific relationships of phytoplankton-microbe symbiotic interactions remain unclear. Here, we investigated effects of environmentally relevant H2O2 concentrations on interspecific microbial relationships in algae-microbe symbiosis. Microbes play a crucial role in the competition between M. aeruginosa and Chlorella vulgaris at low H2O2 concentrations (∼400 nM), in which fungi and bacteria protect Microcystis aeruginosa from oxidative stress. Moreover, H2O2 stimulated the synthesis and release of extracellular microcystin-LR from Microcystis aeruginosa, while intracellular microcystin-LR concentrations remained at a relatively constant level. In the presence of H2O2, loss of organoheterocyclic compounds, organic acids and ketones contributed to the growth of M. aeruginosa, but the reduction of vitamins inhibited it. Regulation of interspecific relationships by H2O2 is achieved by its action on fungal species and bacterial secretory metabolites. This study explored the response of phytoplankton interspecific relationships in symbiotic phytoplankton-microbe interactions to environmentally relevant H2O2 concentrations stress, providing a theoretical basis for understanding the formation of harmful-algae blooming and impact of photochemical properties of water on aquatic ecological safety and stability.
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Affiliation(s)
- Zhe Li
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Hua Ma
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
| | - Zhicheng Hong
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Ting Zhang
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Mingxing Cao
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Fuyi Cui
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Hans-Peter Grossart
- Plankton and Microbial Ecology, Leibniz Institute for Freshwater Ecology and Inland Fisheries (IGB), Zur alten Fischerhuette 2, Neuglobsow 16775, Germany; Institute of Biochemistry and Biology, Potsdam University, Maulbeerallee 2, Potsdam 14469, Germany
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23
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Stark GF, Martin RM, Smith LE, Wei B, Hellweger FL, Bullerjahn GS, McKay RML, Boyer GL, Wilhelm SW. Microcystin aids in cold temperature acclimation: Differences between a toxic Microcystis wildtype and non-toxic mutant. HARMFUL ALGAE 2023; 129:102531. [PMID: 37951605 PMCID: PMC10640677 DOI: 10.1016/j.hal.2023.102531] [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: 08/31/2023] [Revised: 10/20/2023] [Accepted: 10/20/2023] [Indexed: 11/14/2023]
Abstract
For Microcystis aeruginosa PCC 7806, temperature decreases from 26 °C to 19 °C double the microcystin quota per cell during growth in continuous culture. Here we tested whether this increase in microcystin provided M. aeruginosa PCC 7806 with a fitness advantage during colder-temperature growth by comparing cell concentration, cellular physiology, reactive oxygen species damage, and the transcriptomics-inferred metabolism to a non-toxigenic mutant strain M. aeruginosa PCC 7806 ΔmcyB. Photo-physiological data combined with transcriptomic data revealed metabolic changes in the mutant strain during growth at 19 °C, which included increased electron sinks and non-photochemical quenching. Increased gene expression was observed for a glutathione-dependent peroxiredoxin during cold treatment, suggesting compensatory mechanisms to defend against reactive oxygen species are employed in the absence of microcystin in the mutant. Our observations highlight the potential selective advantages of a longer-term defensive strategy in management of oxidative stress (i.e., making microcystin) vs the shorter-term proactive strategy of producing cellular components to actively dissipate or degrade oxidative stress agents.
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Affiliation(s)
- Gwendolyn F Stark
- Department of Microbiology, The University of Tennessee, Knoxville, TN, USA
| | - Robbie M Martin
- Department of Microbiology, The University of Tennessee, Knoxville, TN, USA
| | - Laura E Smith
- Department of Microbiology, The University of Tennessee, Knoxville, TN, USA
| | - Bofan Wei
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, Syracuse, NY, USA
| | - Ferdi L Hellweger
- Water Quality Engineering, Technical University of Berlin, Berlin, Germany
| | - George S Bullerjahn
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, USA
| | - R Michael L McKay
- Great Lakes Institute for Environmental Research, The University of Windsor, Windsor, ON, Canada
| | - Gregory L Boyer
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, Syracuse, NY, USA
| | - Steven W Wilhelm
- Department of Microbiology, The University of Tennessee, Knoxville, TN, USA.
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24
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Collart L, Jiang D, Halsey KH. The volatilome reveals microcystin concentration, microbial composition, and oxidative stress in a critical Oregon freshwater lake. mSystems 2023; 8:e0037923. [PMID: 37589463 PMCID: PMC10654074 DOI: 10.1128/msystems.00379-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 07/03/2023] [Indexed: 08/18/2023] Open
Abstract
IMPORTANCE Harmful algal blooms are among the most significant threats to drinking water safety. Blooms dominated by cyanobacteria can produce potentially harmful toxins and, despite intensive research, toxin production remains unpredictable. We measured gaseous molecules in Upper Klamath Lake, Oregon, over 2 years and used them to predict the presence and concentration of the cyanotoxin, microcystin, and microbial community composition. Subsets of gaseous compounds were identified that are associated with microcystin production during oxidative stress, pointing to ecosystem-level interactions leading to microcystin contamination. Our approach shows potential for gaseous molecules to be harnessed in monitoring critical waterways.
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Affiliation(s)
- Lindsay Collart
- Department of Microbiology, Oregon State University, Corvallis, Oregon, USA
| | - Duo Jiang
- Department of Statistics, Oregon State University, Corvallis, Oregon, USA
| | - Kimberly H. Halsey
- Department of Microbiology, Oregon State University, Corvallis, Oregon, USA
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25
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Sim ZY, Goh KC, He Y, Gin KYH. Present and future potential role of toxin-producing Synechococcus in the tropical region. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 896:165230. [PMID: 37400026 DOI: 10.1016/j.scitotenv.2023.165230] [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: 05/16/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/05/2023]
Abstract
As anthropogenic induced temperature rises and nutrient loadings increase in fresh and brackish environments, the ecological function of the phytoplankton community is expected to favour the picocyanobacteria, of the genus Synechococcus. Synechococcus is already a ubiquitous cyanobacterium found in both freshwater and marine environments, notwithstanding that the toxigenic species still remains unexplored in many freshwaters. Their fast growth rate and their ability to produce toxins make Synechococcus a potential dominant player in harmful algal blooms under climate change scenarios. This study examines the responses of a novel toxin-producing Synechococcus (i.e., one belonging to a freshwater clade; the other belonging to a brackish clade) to environmental changes that reflect climate change effects. We conducted a series of controlled experiments under present and predicted future temperatures, as well as under various N and P nutrients loadings. Our findings highlight how Synechococcus can be altered by the differing reactions to increasing temperature and nutrients, which resulted in considerable variations in cell abundance, growth rate, death rate, cellular stoichiometry and toxin production. Synechococcus had the highest growth observed at 28 °C, and further increases in temperature resulted in a decline for both fresh and brackish waters. Cellular stoichiometry was also altered, where more nitrogen (N) per cell was required, and the plasticity of N:P was more severe for the brackish clade. However, Synechococcus become more toxic under future scenario. Anatoxin-a (ATX) saw the greatest spike when temperature was at 34 °C especially under P-enrichment conditions. In contrast, Cylindrospermopsin (CYN) was promoted at the lowest tested temperature (25 °C) and under N-limitation. Overall, both temperature and external nutrients are the dominant control over Synechococcus toxins production. A model was also created to assess Synechococcus toxicity to zooplankton grazing. Zooplankton grazing was reduced by two folds under nutrient limitation, but temperature accounted for very insignificant change.
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Affiliation(s)
- Zhi Yang Sim
- National University of Singapore Environmental Research Institute, National University of Singapore, 1 Create Way, #15-02, Singapore 138602, Singapore
| | - Kwan Chien Goh
- National University of Singapore Environmental Research Institute, National University of Singapore, 1 Create Way, #15-02, Singapore 138602, Singapore
| | - Yiliang He
- National University of Singapore Center for Eco-Environment Research, Nanjing Hydraulic Research Institute, Nanjing 210098, China
| | - K Y H Gin
- National University of Singapore Environmental Research Institute, National University of Singapore, 1 Create Way, #15-02, Singapore 138602, Singapore; Department of Civil and Environmental Engineering, National University of Singapore, Blk E1A-07-03, 1 Engineering Drive 2, Singapore 117576, Singapore.
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26
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Chen Q, Wang Z, Wei H, Wang J, Zhou W, Zhou P, Li D. Environmental concentrations of anionic surfactants in lake surface microlayers enhance the toxicity of Microcystis blooms: Insight from photosynthesis, interspecies competition, and MC production. WATER RESEARCH 2023; 244:120430. [PMID: 37678037 DOI: 10.1016/j.watres.2023.120430] [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: 06/06/2023] [Revised: 07/25/2023] [Accepted: 07/27/2023] [Indexed: 09/09/2023]
Abstract
Anionic surfactants represented by linear alkylbenzene sulfonate (LAS) exhibit vertical heterogeneity of concentrations in aquatic environments owing to their amphiphilic structure. Field investigations showed that the concentration of anionic surfactants (mainly LAS) in the water surface microlayer (SML) of Lake Taihu reached 580 μg/L, higher than that in the lower layer. Floating Microcystis blooms overlap in space with the high concentration of anionic surfactants in SML. However, few studies have focused on the effects of anionic surfactants (e.g., LAS) on the interspecies competition between toxic and nontoxic Microcystis. In this study, coculture and monoculture experiments were conducted with both toxic and nontoxic Microcystis species to explore how the environmental concentration of LAS regulates the dominance of toxic Microcystis and toxicity from the perspective of photosynthesis, species dominance, and MC production. The results showed that LAS concentrations above 0.267 or 0.431 mg/L (depending on light conditions) selectively promoted the photosynthetic competitive advantage of toxic Microcystis, leading to its higher population proportion in the community. Additionally, LAS concentrations above 0.5 mg/L induced the synthesis and release of microcystins (MCs). The results of chlorophyll fluorescence analysis, electron microscopy and transcriptome sequencing suggested that compared with nontoxic Microcystis, toxic Microcystis can better resist LAS stress by dissipating excess light, maintaining an intact membrane structure and maintaining cellular homeostasis. Transcriptome sequencing revealed that the photosynthetic damage of nontoxic Microcystis might be attributed to the impacts of LAS on the absorption and assimilation of nitrogen, which finally resulted in the degradation of phycobilisomes. This study can provide novel insight for establishing standards and safety management of wastewater discharge.
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Affiliation(s)
- Qinyi Chen
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P.R. China; University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Zhicong Wang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P.R. China.
| | - Hui Wei
- Yulin Municipal Ecology and Environment Emergency and Technical Service Center, Yulin 537000, P.R. China
| | - Jinglong Wang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P.R. China; University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Weicheng Zhou
- School of Chemistry and Environmental Science, Xiangnan University, Chenzhou 423000, P.R. China
| | - Panpan Zhou
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P.R. China; University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Dunhai Li
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P.R. China
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27
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D'ors A, Sánchez-Fortún A, Cortés-Téllez AA, Fajardo C, Mengs G, Nande M, Martín C, Costa G, Martín M, Bartolomé MC, Sánchez-Fortún S. Adverse effects of iron-based nanoparticles on freshwater phytoplankton Scenedesmus armatus and Microcystis aeruginosa strains. CHEMOSPHERE 2023; 339:139710. [PMID: 37532199 DOI: 10.1016/j.chemosphere.2023.139710] [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: 06/19/2023] [Revised: 07/29/2023] [Accepted: 07/31/2023] [Indexed: 08/04/2023]
Abstract
Zero-valent nano-iron particles (nZVI) are increasingly present in freshwater aquatic environments due to their numerous applications in environmental remediation. However, despite the broad benefits associated with the use and development of nZVI nanoparticles, the potential risks of introducing them into the aquatic environment need to be considered. Special attention should be focused on primary producer organisms, the basal trophic level, whose impact affects the rest of the food web. Although there are numerous acute studies on the acute effects of these nanoparticles on photosynthetic primary producers, few studies focus on long-term exposures. The present study aimed at assessing the effects of nZVI on growth rate, photosynthesis activity, and reactive oxygen activity (ROS) on the freshwater green algae Scenedesmus armatus and the cyanobacteria Microcystis aeruginosa. Moreover, microcystin production was also evaluated. These parameters were assessed on both organisms singly exposed to 72 h-effective nZVI concentration for 10% maximal response for 28 days. The results showed that the cell growth rate of S. armatus was initially significantly altered and progressively reached control-like values at 28 days post-exposure, while M. aeruginosa did not show any significant difference concerning control values at any time. In both strains dark respiration (R) increased, unlike net photosynthesis (Pn), while gross photosynthesis (Pg) only slightly increased at 7 days of exposure and then became equal to control values at 28 days of exposure. The nZVI nanoparticles generated ROS progressively during the 28 days of exposure in both strains, although their formation was significantly higher on green algae than on cyanobacteria. These data can provide additional information to further investigate the potential risks of nZVI and ultimately help decision-makers make better informed decisions regarding the use of nZVI for environmental remediation.
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Affiliation(s)
- A D'ors
- Dpt. of Pharmacology and Toxicology, Universidad Complutense de Madrid (UCM), w/n Puerta de Hierro Ave, 28040, Madrid, Spain
| | - A Sánchez-Fortún
- Dpt. of Pharmacology and Toxicology, Universidad Complutense de Madrid (UCM), w/n Puerta de Hierro Ave, 28040, Madrid, Spain
| | - A A Cortés-Téllez
- Environmental Toxicology Laboratory, Faculty of Chemistry-Pharmacobiology, Universidad Michoacana de San Nicolás de Hidalgo, 403 Santiago Tapia St, 58000, Morelia, (Michoacán), Mexico
| | - C Fajardo
- Dpt. of Biomedicine and Biotechnology, Universidad de Alcalá (UAH), w/n San Diego Sq, 28801, Alcalá de Henares, Spain
| | - G Mengs
- Technical and R&D Department, Ecotoxilab SL, 10 Juan XXIII, 28550, Tielmes, Spain
| | - M Nande
- Dpt. of Biochemistry and Molecular Biology, Complutense University, w/n Puerta de Hierro Ave, 28040, Madrid, Spain
| | - C Martín
- Dpt. of Biotechnology-Plant Biology, Universidad Politécnica de Madrid (UPM), 3 Complutense Ave, 28040, Madrid, Spain
| | - G Costa
- Department of Animal Physiology, Faculty of Veterinary Sciences, Complutense University, w/n Puerta de Hierro Ave, 28040, Madrid, Spain
| | - M Martín
- Dpt. of Biochemistry and Molecular Biology, Complutense University, w/n Puerta de Hierro Ave, 28040, Madrid, Spain
| | - M C Bartolomé
- Environmental Toxicology Laboratory, Faculty of Chemistry-Pharmacobiology, Universidad Michoacana de San Nicolás de Hidalgo, 403 Santiago Tapia St, 58000, Morelia, (Michoacán), Mexico.
| | - S Sánchez-Fortún
- Dpt. of Pharmacology and Toxicology, Universidad Complutense de Madrid (UCM), w/n Puerta de Hierro Ave, 28040, Madrid, Spain.
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Qin H, Sandrini G, Piel T, Slot PC, Huisman J, Visser PM. The harmful cyanobacterium Microcystis aeruginosa PCC7806 is more resistant to hydrogen peroxide at elevated CO 2. HARMFUL ALGAE 2023; 128:102482. [PMID: 37714576 DOI: 10.1016/j.hal.2023.102482] [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: 03/01/2023] [Revised: 07/28/2023] [Accepted: 07/28/2023] [Indexed: 09/17/2023]
Abstract
Rising atmospheric CO2 can intensify harmful cyanobacterial blooms in eutrophic lakes. Worldwide, these blooms are an increasing environmental concern. Low concentrations of hydrogen peroxide (H2O2) have been proposed as a short-term but eco-friendly approach to selectively mitigate cyanobacterial blooms. However, sensitivity of cyanobacteria to H2O2 can vary depending on the available resources. To find out how cyanobacteria respond to H2O2 under elevated CO2, Microcystis aeruginosa PCC 7806 was cultured in chemostats with nutrient-replete medium under C-limiting and C-replete conditions (150 ppm and 1500 ppm CO2, respectively). Microcystis chemostats exposed to high CO2 showed higher cell densities, biovolumes, and microcystin contents, but a lower photosynthetic efficiency and pH compared to the cultures grown under low CO2. Subsamples of the chemostats were treated with different concentrations of H2O2 (0-10 mg·L-1 H2O2) in batch cultures under two different light intensities (15 and 100 μmol photons m-2·s-1) and the response in photosynthetic vitality was monitored during 24 h. Results showed that Microcystis was more resistant to H2O2 at elevated CO2 than under carbon-limited conditions. Both low and high CO2-adapted cells were more sensitive to H2O2 at high light than at low light. Microcystins (MCs) leaked out of the cells of cultures exposed to 2-10 mg·L-1 H2O2, while the sum of intra- and extracellular MCs decreased. Although both H2O2 and CO2 concentrations in lakes vary in response to many factors, these results imply that it may become more difficult to suppress cyanobacterial blooms in eutrophic lakes when atmospheric CO2 concentrations continue to rise.
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Affiliation(s)
- Hongjie Qin
- Guangdong Provincial Key Lab of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, PO Box 94240, 1090 GE Amsterdam, The Netherlands; Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Giovanni Sandrini
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, PO Box 94240, 1090 GE Amsterdam, The Netherlands; Department of Technology & Sources, Evides Water Company, Rotterdam, The Netherlands
| | - Tim Piel
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, PO Box 94240, 1090 GE Amsterdam, The Netherlands
| | - Pieter C Slot
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, PO Box 94240, 1090 GE Amsterdam, The Netherlands
| | - Jef Huisman
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, PO Box 94240, 1090 GE Amsterdam, The Netherlands
| | - Petra M Visser
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, PO Box 94240, 1090 GE Amsterdam, The Netherlands.
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29
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Guo Y, Meng H, Zhao S, Wang Z, Zhu L, Deng D, Liu J, He H, Xie W, Wang G, Zhang L. How does Microcystis aeruginosa respond to elevated temperature? THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 889:164277. [PMID: 37211116 DOI: 10.1016/j.scitotenv.2023.164277] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 05/05/2023] [Accepted: 05/15/2023] [Indexed: 05/23/2023]
Abstract
Cyanobacteria and their toxins widely exist in freshwater ecosystems. Microcystis aeruginosa is among dominant bloom-forming cyanobacteria. Water temperature is a key factor influencing the life cycle of M. aeruginosa. We simulated elevated temperature (4-35 °C) experiment and cultured M. aeruginosa during the overwintering, recruitment and rapid growth phases. The results showed that M. aeruginosa recovered growth after overwintering at 4-8 °C and recruited at 16 °C. The total extracellular polymeric substance (TEPS) concentration increased rapidly at 15 °C. The actual quantum yield of photosystem II (Fv'/Fm') peaked at 20 °C during the rapid growth phase, and the optimum temperature of M. aeruginosa growth was 20-25 °C. Additionally, TEPS and microcystins (MCs) secretion peaked at 20-25 °C. The cell density accumulated rapidly from 26 °C to 35 °C. Furthermore, enzymes of RuBisCO and FBA related to photosynthetic activity were confirmed to contribute to the metabolism, as well as mcyB gene was affected by elevated temperature. Our results provide insights of the physiological effects and metabolic activity during annual cycle of M. aeruginosa. And it is predicted that global warming may promote the earlier recruitment of M. aeruginosa, extend the optimum growth period, enhance the toxicity, and finally intensify M. aeruginosa blooms.
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Affiliation(s)
- Yongqi Guo
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, 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, China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing 210023, China
| | - Sichuan Zhao
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, 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, China
| | - Lin Zhu
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China
| | - Dailan Deng
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China
| | - Jine Liu
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, 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, 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, China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing 210023, China
| | - Guoxiang Wang
- School of Environment, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, 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, China; Green Economy Development Institute, Nanjing University of Finance and Economics, Nanjing 210023, China.
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30
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Roy S, Guljamow A, Dittmann E. Impact of temperature on the temporal dynamics of microcystin in Microcystis aeruginosa PCC7806. Front Microbiol 2023; 14:1200816. [PMID: 37720143 PMCID: PMC10500830 DOI: 10.3389/fmicb.2023.1200816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 08/17/2023] [Indexed: 09/19/2023] Open
Abstract
Cyanobacterial blooms pose a serious threat to water quality and human health due to the production of the potent hepatotoxin microcystin. In microcystin-producing strains of the widespread genus Microcystis, the toxin is largely constitutively produced, but there are fluctuations between the cellular and extracellular pool and between free microcystin and protein-bound microcystin. Here we addressed the question of how different temperatures affect the growth and temporal dynamics of secondary metabolite production in the strain Microcystis aeruginosa PCC7806 and its microcystin-deficient ΔmcyB mutant. While the wild-type strain showed pronounced growth advantages at 20°C, 30°C, and 35°C, respectively, the ΔmcyB mutant was superior at 25°C. We further show that short-term incubations at 25°C-35°C result in lower amounts of freely soluble microcystin than incubations at 20°C and that microcystin congener ratios differ at the different temperatures. Subsequent assessment of the protein-bound microcystin pool by dot blot analysis and subcellular localization of microcystin using immunofluorescence microscopy showed re-localization of microcystin into the protein-bound pool combined with an enhanced condensation at the cytoplasmic membrane at temperatures above 25°C. This temperature threshold also applies to the condensate formation of the carbon-fixing enzyme RubisCO thereby likely contributing to reciprocal growth advantages of wild type and ΔmcyB mutant at 20°C and 25°C. We discuss these findings in the context of the environmental success of Microcystis at higher temperatures.
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Affiliation(s)
| | | | - Elke Dittmann
- Department of Microbiology, Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
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31
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Stark GF, Martin RM, Smith LE, Wei B, Hellweger FL, Bullerjahn GS, McKay RML, Boyer GL, Wilhelm SW. Cool temperature acclimation in toxigenic Microcystis aeruginosa PCC 7806 and its non-toxigenic mutant. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.28.555099. [PMID: 37693631 PMCID: PMC10491114 DOI: 10.1101/2023.08.28.555099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
For Microcystis aeruginosa PCC 7806, temperature decreases from 26° C to 19° C double the microcystin quota per cell during growth in continuous culture. Here we tested whether this increase in microcystin provided M. aeruginosa PCC 7806 with a fitness advantage during colder-temperature growth by comparing cell concentration, cellular physiology, and the transcriptomics-inferred metabolism to a non-toxigenic mutant strain M. aeruginosa PCC 7806 ΔmcyB. Photo-physiological data combined with transcriptomic data revealed metabolic changes in the mutant strain during growth at 19° C, which included increased electron sinks and non-photochemical quenching. Increased gene expression was observed for a glutathione-dependent peroxiredoxin during cold treatment, suggesting compensatory mechanisms to defend against reactive oxygen species are employed in the absence of microcystin in the mutant. Our observations highlight the potential selective advantages of a longer-term defensive strategy in management of oxidative stress (i.e., making microcystin) vs the shorter-term proactive strategy of producing cellular components to actively dissipate or degrade oxidative stress agents.
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Affiliation(s)
- Gwendolyn F Stark
- Department of Microbiology, The University of Tennessee, Knoxville, TN, USA
| | - Robbie M Martin
- Department of Microbiology, The University of Tennessee, Knoxville, TN, USA
| | - Laura E Smith
- Department of Microbiology, The University of Tennessee, Knoxville, TN, USA
| | - Bofan Wei
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, Syracuse, NY, USA
| | - Ferdi L Hellweger
- Water Quality Engineering, Technical University of Berlin, Berlin, Germany
| | - George S Bullerjahn
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, USA
| | - R Michael L McKay
- Great Lakes Institute for Environmental Research, The University of Windsor, Windsor, ON, Canada
| | - Gregory L Boyer
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, Syracuse, NY, USA
| | - Steven W Wilhelm
- Department of Microbiology, The University of Tennessee, Knoxville, TN, USA
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32
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de Lima Pinheiro MM, Temponi Santos BL, Vieira Dantas Filho J, Perez Pedroti V, Cavali J, Brito dos Santos R, Oliveira Carreira Nishiyama AC, Guedes EAC, de Vargas Schons S. First monitoring of cyanobacteria and cyanotoxins in freshwater from fish farms in Rondônia state, Brazil. Heliyon 2023; 9:e18518. [PMID: 37520970 PMCID: PMC10374934 DOI: 10.1016/j.heliyon.2023.e18518] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/07/2023] [Accepted: 07/19/2023] [Indexed: 08/01/2023] Open
Abstract
The main aimed of this study was to evaluate the physicochemical parameters, abundance and density of cyanobacteria, determine their blooms and the ecotoxicological risk of their cyanotoxins in fish ponds water. This study was conducted out in 20 fish farms in Rondônia state (Brazilian Amazon), samplings were carried out in the rainy and dry seasons. The experiment was developed in a completely randomized factorial design 20 × 3 x 3 (20 fish farms, 3 ponds and 3 replications). Regarding the composition of qualitative samples, horizontal and vertical hauls were carried out on the water surface, quantitative samples was obtained using a plankton net (50 μm mesh opening). Meanwhile, with the use of a multiparametric probe, physicochemical analyzes in fish ponds water were carried out. Furthermore, the cyanobacteria found were classified taxonomically and its blooms were recorded. Finally, blood was collected from 60 Colossoma macropomum. Concerning the higher averages in the rainy season 6.13 mg L⁻1 of dissolved oxygen, 40.02 cm of transparency, 0.35 NO31⁻ of nitrate, 0.15 NO21⁻ of nitrite, 44.55 mg L⁻1 CaCO3 of alkalinity and 50.10 mg L⁻1 CaCO3 of hardness, while higher averages of pH, phosphate and phosphorus were found in the dry season. A total of 15 families and 29 species of cyanobacteria were identified in the different seasons. The families that showed the highest densities (rainy and dry seasons) were Microcystaceae (356 and 760 cells mL⁻1), Leptolyngbyaceae (126 and 287 cells mL⁻1) and Microcoleaceae (111 and 405 cells mL⁻1). The species that showed the highest densities were Microcystis aeruginosa (356 and 697 cells mL⁻1), Planktolyngbya limnetica (98 and 257 cells mL⁻1) and Planktothrix sp. (111 and 239 cells mL⁻1). There were significant Pearson's correlations (r > 0.85; p < 0.05) between family abundances and cyanotoxin volume between physicochemical water variables and seasonality. A total of 20 cyanobacteria blooms were recorded, all of which in the dry season showed an ecotoxicological risk. Concerning the assessment mutagenicity in fish blood cells, a total of 78 abnormalities per slide were observed. In the dry season, the expected volume of cyanotoxins in the ponds from fish farms F1 and F4 were above the quantification limit (>QL). Abundance and density of cyanobacteria and their blooms and cyanotoxins can be used as bioindicators of eutrophication and/or water quality and ecotoxicological risk in fish ponds.
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Affiliation(s)
| | | | | | - Vinícius Perez Pedroti
- Programa de Pós-Graduação Em Ciências Ambientais, Universidade Federal de Rondônia, Rolim de Moura, RO, Brazil
| | - Jucilene Cavali
- Programa de Pós-Graduação Em Sanidade e Produção Animal Sustentável Na Amazônia Ocidental, Universidade Federal Do Acre, Rio Branco, AC, Brazil
| | | | | | - Elica Amara Cecilia Guedes
- Centro de Ciências Agrárias e Instituto de Ciências Biológicas e da Saúde, Universidade Federal de Alagoas, Maceió, AL, Brazil
| | - Sandro de Vargas Schons
- Programa de Pós-Graduação Em Ciências Ambientais, Universidade Federal de Rondônia, Rolim de Moura, RO, Brazil
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Bashir F, Bashir A, Bouaïcha N, Chen L, Codd GA, Neilan B, Xu WL, Ziko L, Rajput VD, Minkina T, Arruda RS, Ganai BA. Cyanotoxins, biosynthetic gene clusters, and factors modulating cyanotoxin biosynthesis. World J Microbiol Biotechnol 2023; 39:241. [PMID: 37394567 DOI: 10.1007/s11274-023-03652-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 05/17/2023] [Indexed: 07/04/2023]
Abstract
Cyanobacterial harmful algal blooms (CHABs) are a global environmental concern that encompasses public health issues, water availability, and water quality owing to the production of various secondary metabolites (SMs), including cyanotoxins in freshwater, brackish water, and marine ecosystems. The frequency, extent, magnitude, and duration of CHABs are increasing globally. Cyanobacterial species traits and changing environmental conditions, including anthropogenic pressure, eutrophication, and global climate change, together allow cyanobacteria to thrive. The cyanotoxins include a diverse range of low molecular weight compounds with varying biochemical properties and modes of action. With the application of modern molecular biology techniques, many important aspects of cyanobacteria are being elucidated, including aspects of their diversity, gene-environment interactions, and genes that express cyanotoxins. The toxicological, environmental, and economic impacts of CHABs strongly advocate the need for continuing, extensive efforts to monitor cyanobacterial growth and to understand the mechanisms regulating species composition and cyanotoxin biosynthesis. In this review, we critically examined the genomic organization of some cyanobacterial species that lead to the production of cyanotoxins and their characteristic properties discovered to date.
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Affiliation(s)
- Fahim Bashir
- Department of Environmental Science, University of Kashmir, Srinagar, Jammu and Kashmir, 190006, India
| | - Arif Bashir
- Department of Clinical Biochemistry and Biotechnology, Government College for Women, Nawa-Kadal, Srinagar, Jammu & Kashmir, India
| | - Noureddine Bouaïcha
- Laboratory Ecology, Systematic, and Evolution, UMR 8079 Univ. Paris-Sud, CNRS, AgroParisTech, University Paris-Saclay, 91190, Gif-sur-Yvette, France.
| | - Liang Chen
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science (SEES), Yunnan University (YNU), 650500, Kunming, China.
- Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology (IHB), Chinese Academy of Sciences (CAS), Wuhan, 430072, China.
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Faculty of Water Resources and Hydroelectric Engineering, Xi'an University of Technology, Xi'an, 710048, China.
| | - Geoffrey A Codd
- Biological and Environmental Sciences, University of Stirling, Stirling, FK9 4LA, Scotland, UK
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, UK
| | - Brett Neilan
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW, Australia
| | - Wen-Li Xu
- Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology (IHB), Chinese Academy of Sciences (CAS), Wuhan, 430072, China
| | - Laila Ziko
- School of Life and Medical Sciences, University of Hertfordshire Hosted By Global Academic Foundation, Cairo, Egypt
- Biology Department, School of Sciences and Engineering, The American University in Cairo, New Cairo, 11835, Egypt
| | - Vishnu D Rajput
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-On-Don, Russia
| | - Tatiana Minkina
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-On-Don, Russia
| | - Renan Silva Arruda
- Laboratory of Ecology and Physiology of Phytoplankton, Department of Plant Biology, University of Rio de Janeiro State, Rio de Janeiro, Brazil
| | - Bashir Ahmad Ganai
- Center of Research for Development (CORD), University of Kashmir, Srinagar, Jammu and Kashmir, 190006, India.
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Urakawa H, Steele JH, Hancock TL, Dahedl EK, Schroeder ER, Sereda JV, Kratz MA, García PE, Armstrong RA. Interaction among spring phytoplankton succession, water discharge patterns, and hydrogen peroxide dynamics in the Caloosahatchee River in southwest Florida. HARMFUL ALGAE 2023; 126:102434. [PMID: 37290882 DOI: 10.1016/j.hal.2023.102434] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/30/2023] [Accepted: 04/05/2023] [Indexed: 06/10/2023]
Abstract
Phytoplankton communities are major primary producers in the aquatic realm and are responsible for shaping aquatic ecosystems. The dynamics of algal blooms could be determined by a succession of variable taxonomic groups, which are altered based on complex environmental factors such as nutrient availability and hydraulic factors. In-river structures potentially increase the occurrence of harmful algal blooms (HABs) by increasing water residence time and deteriorating water quality. How flowing water stimulates cell growth and affects the population dynamics of phytoplankton communities is a prioritized question that needs to be addressed for water management tactics. The goal of this study was to determine if an interaction between water flow and water chemistry is present, furthermore, to determine the relationship among phytoplankton community successions in the Caloosahatchee River, a subtropical river strongly influenced by human-controlled water discharge patterns from Lake Okeechobee. Particularly we focused on how phytoplankton community shifts influence the natural abundance of hydrogen peroxide, the most stable reactive oxygen species and a byproduct of oxidative photosynthesis. High-throughput amplicon sequencing using universal primers amplify 23S rRNA gene in cyanobacteria and eukaryotic algal plastids revealed that Synechococcus and Cyanobium were the dominant cyanobacterial genera and their relative abundance ranged between 19.5 and 95.3% of the whole community throughout the monitoring period. Their relative abundance declined when the water discharge increased. On the contrary, the relative abundance of eukaryotic algae sharply increased after water discharge increased. As water temperature increased in May, initially dominant Dolichospermum decreased as Microcystis increased. When Microcystis declined other filamentous cyanobacteria such as Geitlerinema, Pseudanabaena, and Prochlorothreix increased in their relative abundances. Interestingly, a peak of extracellular hydrogen peroxide was observed when Dolichospermum dominance was ended, and M. aeruginosa numbers increased. Overall, phytoplankton communities were strongly impacted by human-induced water discharge patterns.
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Affiliation(s)
- Hidetoshi Urakawa
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL 33965, USA; School of Geosciences, University of South Florida, Tampa, FL 33620, USA.
| | - Jacob H Steele
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL 33965, USA
| | - Taylor L Hancock
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL 33965, USA; School of Geosciences, University of South Florida, Tampa, FL 33620, USA
| | - Elizabeth K Dahedl
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL 33965, USA
| | - Elizabeth R Schroeder
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL 33965, USA
| | - Julia V Sereda
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL 33965, USA
| | - Michael A Kratz
- Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL 33965, USA
| | - Patricia E García
- Grupo de Ecología de Sistemas Acuáticos a escala de Paisaje (GESAP), INIBIOMA, Universidad Nacional del Comahue, CONICET, Quintral 1250, CP8400 San Carlos de Bariloche, Argentina
| | - Rick A Armstrong
- Lee County Environmental Laboratory, Fort Myers, FL 33907, United States of America
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Yancey CE, Yu F, Tripathi A, Sherman DH, Dick GJ. Expression of Microcystis Biosynthetic Gene Clusters in Natural Populations Suggests Temporally Dynamic Synthesis of Novel and Known Secondary Metabolites in Western Lake Erie. Appl Environ Microbiol 2023; 89:e0209222. [PMID: 37070981 PMCID: PMC10231183 DOI: 10.1128/aem.02092-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 03/02/2023] [Indexed: 04/19/2023] Open
Abstract
Microcystis spp. produce diverse secondary metabolites within freshwater cyanobacterial harmful algal blooms (cyanoHABs) around the world. In addition to the biosynthetic gene clusters (BGCs) encoding known compounds, Microcystis genomes harbor numerous BGCs of unknown function, indicating a poorly understood chemical repertoire. While recent studies show that Microcystis produces several metabolites in the lab and field, little work has focused on analyzing the abundance and expression of its broader suite of BGCs during cyanoHAB events. Here, we use metagenomic and metatranscriptomic approaches to track the relative abundance of Microcystis BGCs and their transcripts throughout the 2014 western Lake Erie cyanoHAB. The results indicate the presence of several transcriptionally active BGCs that are predicted to synthesize both known and novel secondary metabolites. The abundance and expression of these BGCs shifted throughout the bloom, with transcript abundance levels correlating with temperature, nitrate, and phosphorus concentrations and the abundance of co-occurring predatory and competitive eukaryotic microorganisms, suggesting the importance of both abiotic and biotic controls in regulating expression. This work highlights the need for understanding the chemical ecology and potential risks to human and environmental health posed by secondary metabolites that are produced but often unmonitored. It also indicates the prospects for identifying pharmaceutical-like molecules from cyanoHAB-derived BGCs. IMPORTANCE Microcystis spp. dominate cyanobacterial harmful algal blooms (cyanoHABs) worldwide and pose significant threats to water quality through the production of secondary metabolites, many of which are toxic. While the toxicity and biochemistry of microcystins and several other compounds have been studied, the broader suite of secondary metabolites produced by Microcystis remains poorly understood, leaving gaps in our understanding of their impacts on human and ecosystem health. We used community DNA and RNA sequences to track the diversity of genes encoding synthesis of secondary metabolites in natural Microcystis populations and assess patterns of transcription in western Lake Erie cyanoHABs. Our results reveal the presence of both known gene clusters that encode toxic secondary metabolites as well as novel ones that may encode cryptic compounds. This research highlights the need for targeted studies of the secondary metabolite diversity in western Lake Erie, a vital freshwater source to the United States and Canada.
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Affiliation(s)
- Colleen E. Yancey
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, Michigan, USA
| | - Fengan Yu
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA
| | - Ashootosh Tripathi
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA
- Natural Products Discovery Core, University of Michigan, Ann Arbor, Michigan, USA
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - David H. Sherman
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan, USA
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
| | - Gregory J. Dick
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, Michigan, USA
- Cooperative Institute for Great Lakes Research (CIGLR), University of Michigan, Ann Arbor, Michigan, USA
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Wu D, Deng L, Wang T, Du W, Yin Y, Guo H. Aging process does not necessarily enhance the toxicity of polystyrene microplastics to Microcystis aeruginosa. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 882:163608. [PMID: 37087009 DOI: 10.1016/j.scitotenv.2023.163608] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 04/15/2023] [Accepted: 04/16/2023] [Indexed: 05/03/2023]
Abstract
Microplastic (MP) pollution in aquatic systems has attracted increasing attention in recent years. MPs will inevitably encounter aging process in the environment. However, research on the effects of aged MPs on freshwater ecosystems remains limited. This study compared the properties of pristine and aged polystyrene (PS) MPs of different sizes (20 nm, 200 nm, 2000 nm) and determined the effects of aging on the toxicity of PS MPs to typical freshwater cyanobacteria, Microcystis aeruginosa. Aging process induced significant changes to the properties of the MPs, especially their microstructures and surface functional groups. Aging process also influenced zeta potential, which could further affect stability and toxicity of PS MPs. After 96 h exposure, increase of algal growth and photosynthetic activity was observed in the treatment of pristine 200 nm, aged 20 nm and aged 200 nm PS MPs. In addition, pristine 20 nm, pristine 200 nm, pristine 2000 nm, aged 20 nm and aged 200 nm PS MPs were adsorbed on algal cell surface, which could influence the cell permeability. Pristine PS MPs promoted microcystin synthesis and release, which could do harm to drinking water safety and freshwater ecosystems. However, there was no significant increase in aged PS MPs treatments. Furthermore, the increased 13C content of algal cells in all pristine PS MPs treatments indicated that M. aeruginosa assimilated more CO2 and generate more energy to resist the stress of pristine PS MPs when compared with aged PS MPs. These results indicate that aging process did not necessarily enhance the toxicity and biological risk of PS MPs to freshwater ecosystems. Findings of this study fill the knowledge gap in understanding the effects and risks of aged MPs on freshwater ecosystems.
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Affiliation(s)
- Di Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Lin Deng
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Ting Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Wenchao Du
- School of Environment, Nanjing Normal University, Nanjing 210023, China
| | - Ying Yin
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China; Joint International Research Centre for Critical Zone Science-University of Leeds and Nanjing University, Nanjing University, Nanjing 210023, China.
| | - Hongyan Guo
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China; Joint International Research Centre for Critical Zone Science-University of Leeds and Nanjing University, Nanjing University, Nanjing 210023, China
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Li J, Chen Y, Wan Q, Zhang M. Phosphorus level impacts luteolin effect on Microcystis aeruginosa growth and microcystin-pollution risk - Novel perspective from correlation between exopolymers substances fractions and microcystin-production/release. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 255:114794. [PMID: 36948014 DOI: 10.1016/j.ecoenv.2023.114794] [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: 12/23/2022] [Revised: 03/03/2023] [Accepted: 03/14/2023] [Indexed: 06/18/2023]
Abstract
Luteolin as a phytogenic algicide can inhibit the growth and microcystins (MCs) release of Microcystis, a dominant genus during cyanobacterial blooms, but how phosphorus (P) level impacts luteolin effect on its growth and MC-pollution risk is unclear. By employing Microcystis aeruginosa as test alga, this study addressed this concern and explored response mechanisms from novel insights of relationship between extracellular polysaccharide (ex-poly) and protein (ex-pro) contents and MC-production/release. At each P level (0.05-5 mg/L), rising luteolin dose more greatly inhibited Microcystis growth and MC-pollution risk, with growth inhibition ratio of around 10%-30%, 20%-50% and 40%-90% for 3, 6 and 12 mg/L luteolin, respectively, but almost increasingly enhanced cellular ability of MC-production/conservation and total and bound ex-poly/ex-pro production. Rising P level promoted Microcystis growth and intracellular/extracellular MCs content (IMC, EMC) in test system at each luteolin dose, thus higher P level weakened algicidal and MC-removal effects of luteolin, indicating that P-decrease was required for stronger application outcome of luteolin. Total and bound ex-poly/ex-pro amount were positively correlated with cellular MC-production/conservation ability, IMC and EMC, which constituted cooperative stress-defense of Microcystis at each P level. Besides, rising luteolin dose posed stronger algicidal effect by inactivating gene expression involving peroxidase synthesis (especially at P-limitation), photosynthesis and P acquisition, while rising P level alleviated algicidal and MC-pollution inhibition effects of luteolin by enhancing gene expression involving N acquisition and peroxidase synthesis. This study shed novel insights for P-dependent effect and mechanisms of luteolin on toxigenic Microcystis growth and MC-pollution control, which guided to mitigating toxigenic Microcystis-dominated cyanobacterial blooms in different P-level water areas.
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Affiliation(s)
- Jieming Li
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China.
| | - Yanran Chen
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Qianruo Wan
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Mingxia Zhang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
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Guo Y, Zhao X, Yao Z, Qian Z, Wang Y, Xian Q. The effects of exogenous amino acids on production of microcystin variants in Microcystis aeruginosa. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2023; 259:106525. [PMID: 37087861 DOI: 10.1016/j.aquatox.2023.106525] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 03/25/2023] [Accepted: 04/05/2023] [Indexed: 05/03/2023]
Abstract
Dissolved free amino acids are a significant component of dissolved organic nitrogen (DON) in natural waterbodies. The effects of four amino acids (glutamic acid, phenylalanine, leucine, and arginine) on the growth and microcystins (MCs) production of Microcystis aeruginosa were studied in batch culture. The profiles of five MCs variants and the expression levels of target genes involved in MCs biosynthesis and nitrogen metabolism were measured. When amino acids were used as the sole nitrogen source instead of nitrate at different levels (0.5, 2.0 and 8.0 mg/L based on N) in BG-11 medium, algal cell growth and intracellular MCs quotas were inhibited slightly by the treatments with glutamic acid and arginine. The treatments with phenylalanine and leucine, on the other hand, had a strong inhibitory effect on algal cell growth and MCs production. Moreover, the concentrations of Chlorophyll a, phycocyanin and allophycocyanin in cells cultured in glutamic acid, leucine and phenylalanine were lower than those in the control group with nitrate as nitrogen source. The existence of leucine or phenylalanine can lead to a significant increase in the relative abundance of MCs variants structured with the corresponding amino acids. The expression of microcystin-producing gene mcyD was downregulated while the gene pipX associated with nitrogen metabolism was upregulated during the cultivation of M. aeruginosa with amino acids as sole nitrogen source. M. aeruginosa undergoes significant alterations due to exogenous amino acids and exhibits advanced strategies for MCs production.
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Affiliation(s)
- Yaxin Guo
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Xiating Zhao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Zongcheng Yao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Zongyao Qian
- Guangxi Key Laboratory of Karst Ecological Processes and Services, Huanjiang Observation and Research Station for Karst Ecosystems, Chinese Academy of Sciences, Huanjiang 547100, China
| | - Yuting Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Qiming Xian
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
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Wiśniewska KA, Lewandowska AU, Śliwińska-Wilczewska S, Staniszewska M, Budzałek G. The Ability of Airborne Microalgae and Cyanobacteria to Survive and Transfer the Carcinogenic Benzo(a)pyrene in Coastal Regions. Cells 2023; 12:cells12071073. [PMID: 37048146 PMCID: PMC10093748 DOI: 10.3390/cells12071073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 03/23/2023] [Accepted: 03/30/2023] [Indexed: 04/05/2023] Open
Abstract
Air pollution has been a significant problem threatening human health for years. One commonly reported air pollutant is benzo(a)pyrene, a dangerous compound with carcinogenic properties. Values which exceed normative values for benzo(a)pyrene concentration in the air are often noted in many regions of the world. Studies on the worldwide spread of COVID-19 since 2020, as well as avian flu, measles, and SARS, have proven that viruses and bacteria are more dangerous to human health when they occur in polluted air. Regarding cyanobacteria and microalgae, little is known about their relationship with benzo(a)pyrene. The question is whether these microorganisms can pose a threat when present in poor quality air. We initially assessed whether cyanobacteria and microalgae isolated from the atmosphere are sensitive to changes in PAH concentrations and whether they can accumulate or degrade PAHs. The presence of B(a)P has significantly affected both the quantity of cyanobacteria and microalgae cells as well as their chlorophyll a (chl a) content and their ability to fluorescence. For many cyanobacteria and microalgae, an increase in cell numbers was observed after the addition of B(a)P. Therefore, even slight air pollution with benzo(a)pyrene is likely to facilitate the growth of airborne cyanobacteria and microalgae. The results provided an assessment of the organisms that are most susceptible to cellular stress following exposure to benzo(a)pyrene, as well as the potential consequences for the environment. Additionally, the results indicated that green algae have the greatest potential for degrading PAHs, making their use a promising bioremediation approach. Kirchneriella sp. demonstrated the highest average degradation of B(a)P, with the above-mentioned research indicating it can even degrade up to 80% of B(a)P. The other studied green algae exhibited a lower, yet still significant, B(a)P degradation rate exceeding 50% when compared to cyanobacteria and diatoms.
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Affiliation(s)
- Kinga A. Wiśniewska
- Institute of Oceanography, Department of Chemical Oceanography and Marine Geology, University of Gdansk, Av. M. Piłsudskiego 46, 81-378 Gdynia, Poland
| | - Anita U. Lewandowska
- Institute of Oceanography, Department of Chemical Oceanography and Marine Geology, University of Gdansk, Av. M. Piłsudskiego 46, 81-378 Gdynia, Poland
| | - Sylwia Śliwińska-Wilczewska
- Department of Biology, Mount Allison University, 62 York St., Sackville, NB E4L 1E2, Canada
- Institute of Oceanography, Division of Marine Ecosystems Functioning, University of Gdansk, Al. M. Piłsudskiego 46, 81-378 Gdynia, Poland
| | - Marta Staniszewska
- Institute of Oceanography, Department of Chemical Oceanography and Marine Geology, University of Gdansk, Av. M. Piłsudskiego 46, 81-378 Gdynia, Poland
| | - Gracjana Budzałek
- Institute of Oceanography, Division of Marine Ecosystems Functioning, University of Gdansk, Al. M. Piłsudskiego 46, 81-378 Gdynia, Poland
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40
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Lusty MW, Gobler CJ. Repeated hydrogen peroxide dosing briefly reduces cyanobacterial blooms and microcystin while increasing fecal bacteria indicators in a eutrophic pond. J Environ Sci (China) 2023; 124:522-543. [PMID: 36182161 DOI: 10.1016/j.jes.2021.11.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 06/16/2023]
Abstract
This study explored the effects of H2O2 on Cyanobacteria and non-target microbes using fluorometry, microscopy, flow cytometry, and high throughput DNA sequencing of the 16S rRNA gene during a series of mesocosm and whole-ecosystem experiments in a eutrophic pond in NY, USA. The addition of H2O2 (8 mg/L) significantly reduced Cyanobacteria concentrations during a majority of experiments (66%; 6 of 9) and significantly increased eukaryotic green and unicellular brown algae in 78% and 45% of experiments, respectively. While heterotrophic bacteria declined significantly following H2O2 addition in all experiments, bacteria indicative of potential fecal contamination (Escherichia coli, Enterococcus, fecal coliform bacteria) consistently and significantly increased in response to H2O2, evidencing a form of 'pollution swapping'. H2O2 more effectively reduced Cyanobacteria in enclosed mesocosms compared to whole-ecosystem applications. Ten whole-pond H2O2 applications over a two-year period temporarily reduced cyanobacterial levels but never reduced concentrations below bloom thresholds and populations always rebounded in two weeks or less. The bacterial phyla of Cyanobacteria, Actinobacteria, and Planctomycetes were the most negatively impacted by H2O2. Microcystis was always reduced by H2O2, as was the toxin microcystin, but Microcystis remained dominant even after repeated H2O2 treatments. Although H2O2 favored the growth of eukaryotic algae over potentially harmful Cyanobacteria, the inability of H2O2 to end cyanobacterial blooms in this eutrophic waterbody suggests it is a non-ideal mitigation approach in high biomass ecosystems and should be used judiciously due to potential negative impacts on non-target organisms and promotion of bacteria indicative of fecal contamination.
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Affiliation(s)
- Mark W Lusty
- School of Marine and Atmospheric Sciences, Stony Brook University, Southampton, NY 11968, USA
| | - Christopher J Gobler
- School of Marine and Atmospheric Sciences, Stony Brook University, Southampton, NY 11968, USA.
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Osburn FS, Wagner ND, Taylor RB, Chambliss CK, Brooks BW, Scott JT. The effects of salinity and N:P on N-rich toxins by both an N-fixing and non-N-fixing cyanobacteria. LIMNOLOGY AND OCEANOGRAPHY LETTERS 2023; 8:162-172. [PMID: 36777312 PMCID: PMC9915339 DOI: 10.1002/lol2.10234] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 12/08/2021] [Indexed: 06/18/2023]
Abstract
Freshwater ecosystems are experiencing increased salinization. Adaptive management of harmful algal blooms (HABs) contribute to eutrophication/salinization interactions through the hydrologic transport of blooms to coastal environments. We examined how nutrients and salinity interact to affect growth, elemental composition, and cyanotoxin production/release in two common HAB genera. Microcystis aeruginosa (non-nitrogen (N)-fixer and microcystin-LR producer; MC-LR) and Aphanizomenon flos-aquae (N-fixer and cylindrospermopsin producer; CYN) were grown in N:phosphorus (N:P) 4 and 50 (by atom) for 21 and 33 days, respectively, then dosed with a salinity gradient (0 - 10.5 g L-1). Both total MC-LR and CYN were correlated with particulate N. We found Microcystis MC-LR production and release was affected by salinity only in the N:P 50 treatment. However, Aphanizomenon CYN production and release was affected by salinity regardless of N availability. Our results highlight how cyanotoxin production and release across the freshwater - marine continuum are controlled by eco-physiological differences between N-acquisition traits.
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Affiliation(s)
- Felicia S. Osburn
- Department of Biology, Baylor University, Waco TX USA
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco TX USA
| | - Nicole D. Wagner
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco TX USA
| | - Raegyn B. Taylor
- Department of Chemistry and Biochemistry, Baylor University, Waco TX USA
| | - C. Kevin Chambliss
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco TX USA
- Department of Chemistry and Biochemistry, Baylor University, Waco TX USA
- The Institute for Ecological, Earth, and Environmental Sciences, Baylor University, Waco TX USA
| | - Bryan W. Brooks
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco TX USA
- The Institute for Ecological, Earth, and Environmental Sciences, Baylor University, Waco TX USA
- Department of Environmental Science, Baylor University, Waco TX USA
- Institute of Biomedical Studies, Baylor University, Waco TX USA
| | - J. Thad Scott
- Department of Biology, Baylor University, Waco TX USA
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco TX USA
- The Institute for Ecological, Earth, and Environmental Sciences, Baylor University, Waco TX USA
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Wagner ND, Osburn FS, Taylor RB, Back JA, Chambliss CK, Brooks BW, Scott JT. Diazotrophy modulates cyanobacteria stoichiometry through functional traits that determine bloom magnitude and toxin production. LIMNOLOGY AND OCEANOGRAPHY 2023; 68:348-360. [PMID: 36819961 PMCID: PMC9937718 DOI: 10.1002/lno.12273] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 11/10/2022] [Indexed: 06/18/2023]
Abstract
Harmful cyanobacterial blooms are an increasing threat to water quality. The interactions between two eco-physiological functional traits of cyanobacteria, diazotrophy (nitrogen (N)-fixation) and N-rich cyanotoxin synthesis, have never been examined in a stoichiometric explicit manner. We explored how a gradient of resource N:phosphorus (P) affects the biomass, N, P stoichiometry, light-harvesting pigments, and cylindrospermopsin production in a N-fixing cyanobacterium, Aphanizomenon. Low N:P Aphanizomenon cultures produced the same biomass as populations grown in high N:P cultures. The biomass accumulation determined by carbon, indicated low N:P Aphanizomenon cultures did not have a N-fixation growth tradeoff, in contrast to some other diazotrophs that maintain stoichiometric N homeostasis at the expense of growth. However, N-fixing Aphanizomenon populations produced less particulate cylindrospermopsin and had undetectable dissolved cylindrospermopsin compared to non-N-fixing populations. The pattern of low to high cyanotoxin cell quotas across an N:P gradient in the diazotrophic cylindrospermopsin producer is similar to the cyanotoxin cell quota response in non-diazotrophic cyanobacteria. We suggest that diazotrophic cyanobacteria may be characterized into two broad functional groups, the N-storage-strategists and the growth-strategists, which use N-fixation differently and may determine patterns of bloom magnitude and toxin production in nature.
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Affiliation(s)
- Nicole D Wagner
- Department of Biological Sciences, Oakland University, Rochester MI, 48326, USA
- Center for Reservoir and Aquatic System Research, Baylor University, Waco TX, 76798, USA
| | - Felicia S Osburn
- Center for Reservoir and Aquatic System Research, Baylor University, Waco TX, 76798, USA
- Department of Biology, Baylor University, Waco TX, 76798, USA
- Department of Biology, University of Central Arkansas, Conway AR, 72035, USA
| | - Raegyn B Taylor
- Center for Reservoir and Aquatic System Research, Baylor University, Waco TX, 76798, USA
- Department of Chemistry and Biochemistry, Baylor University, Waco TX, 76798, USA
- United States Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Wyndmoor, PA, 19038, USA
| | - Jeffrey A Back
- Center for Reservoir and Aquatic System Research, Baylor University, Waco TX, 76798, USA
| | - C Kevin Chambliss
- Center for Reservoir and Aquatic System Research, Baylor University, Waco TX, 76798, USA
- Department of Chemistry and Biochemistry, Baylor University, Waco TX, 76798, USA
| | - Bryan W Brooks
- Center for Reservoir and Aquatic System Research, Baylor University, Waco TX, 76798, USA
- Department of Environmental Science, Baylor University, Waco TX, 76798, USA
| | - J Thad Scott
- Center for Reservoir and Aquatic System Research, Baylor University, Waco TX, 76798, USA
- Department of Biology, Baylor University, Waco TX, 76798, USA
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Cai H, McLimans CJ, Beyer JE, Krumholz LR, Hambright KD. Microcystis pangenome reveals cryptic diversity within and across morphospecies. SCIENCE ADVANCES 2023; 9:eadd3783. [PMID: 36638170 PMCID: PMC9839332 DOI: 10.1126/sciadv.add3783] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 12/09/2022] [Indexed: 06/17/2023]
Abstract
Microcystis, a common harmful algal bloom (HAB) taxon, threatens water supplies and human health, yet species delimitation is contentious in this taxon, leading to challenges in research and management of this threat. Historical and common morphology-based classifications recognize multiple morphospecies, most with variable and diverse ecologies, while DNA sequence-based classifications indicate a single species with multiple ecotypes. To better delimit Microcystis species, we conducted a pangenome analysis of 122 genomes. Core- and non-core gene phylogenetic analyses placed 113 genomes into 23 monophyletic clusters containing at least two genomes. Overall, genome-related indices revealed that Microcystis contains at least 16 putative genospecies. Fifteen genospecies included at least one Microcystis aeruginosa morphospecies, and 10 genospecies included two or more morphospecies. This classification system will enable consistent taxonomic identification of Microcystis and thereby aid in resolving some of the complexities and controversies that have long characterized eco-evolutionary research and management of this important HAB taxon.
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Affiliation(s)
- Haiyuan Cai
- Plankton Ecology and Limnology Laboratory, Department of Biology, University of Oklahoma, Norman, OK, USA
| | - Christopher J. McLimans
- Plankton Ecology and Limnology Laboratory, Department of Biology, University of Oklahoma, Norman, OK, USA
- Program in Ecology and Evolutionary Biology, Department of Biology, University of Oklahoma, Norman, OK, USA
| | - Jessica E. Beyer
- Plankton Ecology and Limnology Laboratory, Department of Biology, University of Oklahoma, Norman, OK, USA
- Program in Ecology and Evolutionary Biology, Department of Biology, University of Oklahoma, Norman, OK, USA
| | - Lee R. Krumholz
- Department of Microbiology and Plant Biology and Institute for Energy and the Environment, University of Oklahoma, Norman, OK, USA
| | - K. David Hambright
- Plankton Ecology and Limnology Laboratory, Department of Biology, University of Oklahoma, Norman, OK, USA
- Program in Ecology and Evolutionary Biology, Department of Biology, University of Oklahoma, Norman, OK, USA
- Geographical Ecology, Department of Biology, University of Oklahoma, Norman, OK, USA
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Turner AD, Beach DG, Foss A, Samdal IA, Løvberg KLE, Waack J, Edwards C, Lawton LA, Dean KJ, Maskrey BH, Lewis AM. A Feasibility Study into the Production of a Mussel Matrix Reference Material for the Cyanobacterial Toxins Microcystins and Nodularins. Toxins (Basel) 2022; 15:27. [PMID: 36668847 PMCID: PMC9867187 DOI: 10.3390/toxins15010027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/15/2022] [Accepted: 12/23/2022] [Indexed: 01/03/2023] Open
Abstract
Microcystins and nodularins, produced naturally by certain species of cyanobacteria, have been found to accumulate in aquatic foodstuffs such as fish and shellfish, resulting in a risk to the health of the seafood consumer. Monitoring of toxins in such organisms for risk management purposes requires the availability of certified matrix reference materials to aid method development, validation and routine quality assurance. This study consequently targeted the preparation of a mussel tissue reference material incurred with a range of microcystin analogues and nodularins. Nine targeted analogues were incorporated into the material as confirmed through liquid chromatography with tandem mass spectrometry (LC-MS/MS), with an additional 15 analogues detected using LC coupled to non-targeted high resolution mass spectrometry (LC-HRMS). Toxins in the reference material and additional source tissues were quantified using LC-MS/MS, two different enzyme-linked immunosorbent assay (ELISA) methods and with an oxidative-cleavage method quantifying 3-methoxy-2-methyl-4-phenylbutyric acid (MMPB). Correlations between the concentrations quantified using the different methods were variable, likely relating to differences in assay cross-reactivities and differences in the abilities of each method to detect bound toxins. A consensus concentration of total soluble toxins determined from the four independent test methods was 2425 ± 575 µg/kg wet weight. A mean 43 ± 9% of bound toxins were present in addition to the freely extractable soluble form (57 ± 9%). The reference material produced was homogenous and stable when stored in the freezer for six months without any post-production stabilization applied. Consequently, a cyanotoxin shellfish reference material has been produced which demonstrates the feasibility of developing certified seafood matrix reference materials for a large range of cyanotoxins and could provide a valuable future resource for cyanotoxin risk monitoring, management and mitigation.
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Affiliation(s)
- Andrew D. Turner
- Centre for Environment Fisheries and Aquaculture Science, Barrack Road, Weymouth DT4 8UB, UK
| | - Daniel G. Beach
- Biotoxin Metrology, National Research Council Canada, Halifax, NS B3H 3Z1, Canada
| | - Amanda Foss
- Greenwater Laboratories, 205 Zeagler Drive, Suite 302, Palatka, FL 32177, USA
| | | | | | - Julia Waack
- Centre for Environment Fisheries and Aquaculture Science, Barrack Road, Weymouth DT4 8UB, UK
- CyanoSol, School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen AB10 7GJ, UK
| | - Christine Edwards
- CyanoSol, School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen AB10 7GJ, UK
| | - Linda A. Lawton
- CyanoSol, School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen AB10 7GJ, UK
| | - Karl J. Dean
- Centre for Environment Fisheries and Aquaculture Science, Barrack Road, Weymouth DT4 8UB, UK
| | - Benjamin H. Maskrey
- Centre for Environment Fisheries and Aquaculture Science, Barrack Road, Weymouth DT4 8UB, UK
| | - Adam M. Lewis
- Centre for Environment Fisheries and Aquaculture Science, Barrack Road, Weymouth DT4 8UB, UK
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45
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Facey JA, Violi JP, King JJ, Sarowar C, Apte SC, Mitrovic SM. The Influence of Micronutrient Trace Metals on Microcystis aeruginosa Growth and Toxin Production. Toxins (Basel) 2022; 14:toxins14110812. [PMID: 36422986 PMCID: PMC9694995 DOI: 10.3390/toxins14110812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/14/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022] Open
Abstract
Microcystis aeruginosa is a widespread cyanobacteria capable of producing hepatotoxic microcystins. Understanding the environmental factors that influence its growth and toxin production is essential to managing the negative effects on freshwater systems. Some micronutrients are important cofactors in cyanobacterial proteins and can influence cyanobacterial growth when availability is limited. However, micronutrient requirements are often species specific, and can be influenced by substitution between metals or by luxury uptake. In this study, M. aeruginosa was grown in modified growth media that individually excluded some micronutrients (cobalt, copper, iron, manganese, molybdenum) to assess the effect on growth, toxin production, cell morphology and iron accumulation. M. aeruginosa growth was limited when iron, cobalt and manganese were excluded from the growth media, whereas the exclusion of copper and molybdenum had no effect on growth. Intracellular microcystin-LR concentrations were variable and were at times elevated in treatments undergoing growth limitation by cobalt. Intracellular iron was notably higher in treatments grown in cobalt-deplete media compared to other treatments possibly due to inhibition or competition for transporters, or due to irons role in detoxifying reactive oxygen species (ROS).
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Affiliation(s)
- Jordan A. Facey
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2000, Australia
- Correspondence:
| | - Jake P. Violi
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2000, Australia
| | - Josh J. King
- CSIRO Land and Water, Lucas Heights, Sydney, NSW 2234, Australia
| | - Chowdhury Sarowar
- Prince of Wales Clinical School, University of New South Wales, Kensington, NSW 2052, Australia
| | - Simon C. Apte
- CSIRO Land and Water, Lucas Heights, Sydney, NSW 2234, Australia
| | - Simon M. Mitrovic
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2000, Australia
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Huisman J, Dittmann E, Fastner J, Schuurmans JM, Scott JT, Van de Waal DB, Visser PM, Welker M, Chorus I. Comment on “Models predict planned phosphorus load reduction will make Lake Erie more toxic”. Science 2022; 378:eadd9959. [DOI: 10.1126/science.add9959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Hellweger
et al
. (Reports, 27 May 2022, pp. 1001) predict that phosphorus limitation will increase concentrations of cyanobacterial toxins in lakes. However, several molecular, physiological, and ecological mechanisms assumed in their models are poorly supported or contradicted by other studies. We conclude that their take-home message that phosphorus load reduction will make Lake Erie more toxic is seriously flawed.
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Affiliation(s)
- Jef Huisman
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240, 1090 GE Amsterdam, Netherlands
| | - Elke Dittmann
- Department of Microbiology, Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24/25, 14476 Potsdam-Golm, Germany
| | - Jutta Fastner
- Department of Drinking Water and Swimming Pool Hygiene, German Environment Agency, Berlin, Germany
| | - J. Merijn Schuurmans
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240, 1090 GE Amsterdam, Netherlands
| | - J. Thad Scott
- Department of Biology, Center for Reservoir and Aquatic Systems Research, Baylor University, One Bear Place #97388, Waco, Texas, USA
| | - Dedmer B. Van de Waal
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240, 1090 GE Amsterdam, Netherlands
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, Netherlands
| | - Petra M. Visser
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240, 1090 GE Amsterdam, Netherlands
| | | | - Ingrid Chorus
- Department of Drinking Water and Swimming Pool Hygiene, German Environment Agency, Berlin, Germany
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An G, Li J, Lu H, Guo Z. Nitrogen-dependent luteolin effect on Microcystis growth and microcystin-pollution risk - Novel mechanism insights unveiled by comparative proteomics and gene expression. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 311:119848. [PMID: 35948113 DOI: 10.1016/j.envpol.2022.119848] [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: 04/07/2022] [Revised: 06/19/2022] [Accepted: 07/21/2022] [Indexed: 06/15/2023]
Abstract
Phytogenic allelochemical luteolin has potential to mitigate Microcystis-dominated cyanobacterial blooms (MCBs), but its algicidal effect against toxigenic Microcystis may be impacted by natural factors, especially nitrogen (N) level in waters. This study innovatively explored N-dependent effect of luteolin on Microcystis growth and its microcystins (MCs) production/release, and elucidated underlying mechanisms from proteomics and gene expression views. Generally, at each N level, rising luteolin dose progressively inhibited Microcystis growth by inhibiting proteins syntheses and genes expression involving light-capturing, photosynthetic electron transfer, Calvin cycle and phosphorus (P) acquisition, according to comparative proteomics and gene expression. At higher luteolin dose and lower N level, Microcystis cell tended to increase microcystins (MCs) production and conservation ability, with the highest increase degree observed at 12 mg/L luteolin and 0.5 mg/L N on day 10, reaching 1.96 and 2.68 folds of luteolin-free control, respectively, but decrease MC-release as extracellular MCs content (EMC), with inhibition ratio of 72.86%, 73.57%, 74.45% and 40.58%, 45.28%, 60.00% at rising N level under 12 mg/L luteolin stress on day 10 and 16, respectively. These enabled cellular defensive response of Microcystis to stronger stress and N limitation. Under luteolin stress, higher N level more strongly up-regulated numerous processes (e.g., oxidoreductase activity, ATP binding and transmembrane transport, oxidative phosphorylation, tricarboxylic acid cycle, fatty acid biosynthesis, glycolysis/gluconeogenesis, pyruvate, amino acids metabolism, metal ion-binding, P acquisition) as compensative protective responses to progressively down-regulated photosynthetic and ribosomal processes at higher N level, thus causing faster Microcystis growth than lower N level. This study provided novel insights for N-dependent effect and mechanisms of luteolin on MCBs mitigation and MCs risk control, and guided algicidal application of luteolin in different eutrophic-degree waters.
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Affiliation(s)
- Guangqi An
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China
| | - Jieming Li
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China.
| | - Haifeng Lu
- College of Water Resources and Civil Engineering, China Agricultural University, Beijing, 100083, China
| | - Zhonghui Guo
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China
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48
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Agha R, Gerphagnon M, Schampera C, Rohrlack T, Fastner J, Wolinska J. Fate of hepatotoxin microcystin during infection of cyanobacteria by fungal chytrid parasites. HARMFUL ALGAE 2022; 118:102288. [PMID: 36195431 DOI: 10.1016/j.hal.2022.102288] [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: 03/11/2022] [Revised: 06/08/2022] [Accepted: 07/04/2022] [Indexed: 06/16/2023]
Abstract
Chytrid parasites are increasingly recognized as ubiquitous and potent control agents of phytoplankton, including bloom-forming toxigenic cyanobacteria. In order to explore the fate of the cyanobacterial toxin microcystins (MCs) and assess potential upregulation of their production under parasite attack, a laboratory experiment was conducted to evaluate short- and long-term variation in extracellular and intracellular MC in the cyanobacteria Planktothrix agardhii and P. rubescens, both under chytrid infection and in the presence of lysates of previously infected cyanobacteria. MCs release under parasite infection was limited and not different to uninfected cyanobacteria, with extracellular toxin shares never exceeding 10%, substantially below those caused by mechanical lysis induced by a cold-shock. Intracellular MC contents in P. rubescens under infection were not significantly different from uninfected controls, whereas infected P. agardhii showed a 1.5-fold increase in intracellular MC concentrations, but this was detected within the first 48 hours after parasite inoculation and not later, indicating no substantial MC upregulation in cells being infected. The presence of lysates of previously infected cyanobacteria did not elicit higher intracellular MC contents in exposed cyanobacteria, speaking against a putative upregulation of toxin production induced via quorum sensing in response to parasite attack. These results indicate that chytrid epidemics can constitute a bloom decay mechanism that is not accompanied by massive release of toxins into the medium.
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Affiliation(s)
- Ramsy Agha
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany.
| | - Mélanie Gerphagnon
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Charlotte Schampera
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany; Water Quality Engineering, Technical University of Berlin, Berlin, Germany
| | - Thomas Rohrlack
- Norwegian University of LifeSciences (NMBU), Department of Environmental Sciences, Ås, Norway
| | - Jutta Fastner
- German Environment Agency, Section Protection of Drinking Water Resources, Schichauweg 58, 12307 Berlin
| | - Justyna Wolinska
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany; Department of Biology, Chemistry, Pharmacy, Institute of Biology, Freie Universität Berlin, Berlin, Germany
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Kim Tiam S, Comte K, Dalle C, Delagrange M, Djediat C, Ducos B, Duval C, Feilke K, Hamlaoui S, Le Manach S, Setif P, Yéprémian C, Marie B, Kirilovsky D, Gugger M, Bernard C. The success of the bloom-forming cyanobacteria Planktothrix: Genotypes variability supports variable responses to light and temperature stress. HARMFUL ALGAE 2022; 117:102285. [PMID: 35944963 DOI: 10.1016/j.hal.2022.102285] [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: 02/01/2022] [Revised: 05/05/2022] [Accepted: 06/28/2022] [Indexed: 06/15/2023]
Abstract
Cyanobacterial blooms can modify the dynamic of aquatic ecosystems and have harmful consequences for human activities. Moreover, cyanobacteria can produce a variety of cyanotoxins, including microcystins, but little is known about the role of environmental factors on the prevalence of microcystin producers in the cyanobacterial bloom dynamics. This study aimed to better understand the success of Planktothrix in various environments by unveiling the variety of strategies governing cell responses to sudden changes in light intensity and temperature. The cellular responses (photosynthesis, photoprotection, heat shock response and metabolites synthesis) of four Planktothrix strains to high-light or high-temperature were studied, focusing on how distinct ecotypes (red- or green-pigmented) and microcystin production capability affect cyanobacteria's ability to cope with such abiotic stimuli. Our results showed that high-light and high-temperature impact different cellular processes and that Planktothrix responses are heterogeneous, specific to each strain and thus, to genotype. The ability of cyanobacteria to cope with sudden increase in light intensity and temperature was not related to red- or green-pigmented ecotype or microcystin production capability. According to our results, microcystin producers do not cope better to high-light or high-temperature and microcystin content does not increase in response to such stresses.
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Affiliation(s)
- Sandra Kim Tiam
- UMR 7245 Molécules de Communication et Adaptations des Microorganismes (MCAM), Muséum National d'Histoire Naturelle, CNRS, CP 39, 57 rue Cuvier, Paris, 75005, France.
| | - Katia Comte
- UMR 7245 Molécules de Communication et Adaptations des Microorganismes (MCAM), Muséum National d'Histoire Naturelle, CNRS, CP 39, 57 rue Cuvier, Paris, 75005, France
| | - Caroline Dalle
- Institut Pasteur, Université Paris Cité, Collection of Cyanobacteria, Paris, F-75015, France
| | - Marine Delagrange
- Laboratoire de Physique Statistique, École Normale Supérieure, PSL Research University, Université Paris Diderot Sorbonne Paris-Cité, Sorbonne Université UPMC Paris 06, CNRS, High Throughput qPCR Core Facility of the ENS, IBENS, 46 rue d'Ulm, Paris,, 75005 France
| | - Chakib Djediat
- UMR 7245 Molécules de Communication et Adaptations des Microorganismes (MCAM), Muséum National d'Histoire Naturelle, CNRS, CP 39, 57 rue Cuvier, Paris, 75005, France
| | - Bertrand Ducos
- Laboratoire de Physique Statistique, École Normale Supérieure, PSL Research University, Université Paris Diderot Sorbonne Paris-Cité, Sorbonne Université UPMC Paris 06, CNRS, High Throughput qPCR Core Facility of the ENS, IBENS, 46 rue d'Ulm, Paris,, 75005 France
| | - Charlotte Duval
- UMR 7245 Molécules de Communication et Adaptations des Microorganismes (MCAM), Muséum National d'Histoire Naturelle, CNRS, CP 39, 57 rue Cuvier, Paris, 75005, France
| | - Kathleen Feilke
- Institute for Integrative Biology of the Cell (I2BC), CNRS, CEA, Université Paris-Sud, Université Paris-Saclay, Gif sur Yvette, 91198, France
| | - Sahima Hamlaoui
- UMR 7245 Molécules de Communication et Adaptations des Microorganismes (MCAM), Muséum National d'Histoire Naturelle, CNRS, CP 39, 57 rue Cuvier, Paris, 75005, France
| | - Séverine Le Manach
- UMR 7245 Molécules de Communication et Adaptations des Microorganismes (MCAM), Muséum National d'Histoire Naturelle, CNRS, CP 39, 57 rue Cuvier, Paris, 75005, France
| | - Pierre Setif
- Institute for Integrative Biology of the Cell (I2BC), CNRS, CEA, Université Paris-Sud, Université Paris-Saclay, Gif sur Yvette, 91198, France
| | - Claude Yéprémian
- UMR 7245 Molécules de Communication et Adaptations des Microorganismes (MCAM), Muséum National d'Histoire Naturelle, CNRS, CP 39, 57 rue Cuvier, Paris, 75005, France
| | - Benjamin Marie
- UMR 7245 Molécules de Communication et Adaptations des Microorganismes (MCAM), Muséum National d'Histoire Naturelle, CNRS, CP 39, 57 rue Cuvier, Paris, 75005, France
| | - Diana Kirilovsky
- Institute for Integrative Biology of the Cell (I2BC), CNRS, CEA, Université Paris-Sud, Université Paris-Saclay, Gif sur Yvette, 91198, France
| | - Muriel Gugger
- Institut Pasteur, Université Paris Cité, Collection of Cyanobacteria, Paris, F-75015, France.
| | - Cécile Bernard
- UMR 7245 Molécules de Communication et Adaptations des Microorganismes (MCAM), Muséum National d'Histoire Naturelle, CNRS, CP 39, 57 rue Cuvier, Paris, 75005, France.
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50
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Entfellner E, Li R, Jiang Y, Ru J, Blom J, Deng L, Kurmayer R. Toxic/Bioactive Peptide Synthesis Genes Rearranged by Insertion Sequence Elements Among the Bloom-Forming Cyanobacteria Planktothrix. Front Microbiol 2022; 13:901762. [PMID: 35966708 PMCID: PMC9366434 DOI: 10.3389/fmicb.2022.901762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 06/23/2022] [Indexed: 11/28/2022] Open
Abstract
It has been generally hypothesized that mobile elements can induce genomic rearrangements and influence the distribution and functionality of toxic/bioactive peptide synthesis pathways in microbes. In this study, we performed in depth genomic analysis by completing the genomes of 13 phylogenetically diverse strains of the bloom-forming freshwater cyanobacteria Planktothrix spp. to investigate the role of insertion sequence (IS) elements in seven pathways. Chromosome size varied from 4.7–4.8 Mbp (phylogenetic Lineage 1 of P. agardhii/P. rubescens thriving in shallow waterbodies) to 5.4–5.6 Mbp (Lineage 2 of P. agardhii/P. rubescens thriving in deeper physically stratified lakes and reservoirs) and 6.3–6.6 Mbp (Lineage 3, P. pseudagardhii/P. tepida including planktic and benthic ecotypes). Although the variation in chromosome size was positively related to the proportion of IS elements (1.1–3.7% on chromosome), quantitatively, IS elements and other paralogs only had a minor share in chromosome size variation. Thus, the major part of genomic variation must have resulted from gene loss processes (ancestor of Lineages 1 and 2) and horizontal gene transfer (HGT). Six of seven peptide synthesis gene clusters were found located on the chromosome and occurred already in the ancestor of P. agardhii/P. rubescens, and became partly lost during evolution of Lineage 1. In general, no increased IS element frequency in the vicinity of peptide synthesis gene clusters was observed. We found a higher proportion of IS elements in ten breaking regions related to chromosomal rearrangements and a tendency for colocalization of toxic/bioactive peptide synthesis gene clusters on the chromosome.
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Affiliation(s)
| | - Ruibao Li
- Research Department for Limnology, University of Innsbruck, Mondsee, Austria
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
- Department of Ecology and Institute of Hydrobiology, Jinan University, Guangzhou, China
| | - Yiming Jiang
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| | - Jinlong Ru
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| | - Jochen Blom
- Bioinformatics and Systems Biology, Justus-Liebig-University, Giessen, Germany
| | - Li Deng
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| | - Rainer Kurmayer
- Research Department for Limnology, University of Innsbruck, Mondsee, Austria
- *Correspondence: Rainer Kurmayer,
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