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Zhang S, Zheng T, Zhou M, Niu B, Li Y. Exposure to the mixotrophic dinoflagellate Lepidodinium sp. and its cues increase toxin production of Pseudo-nitzschia multiseries. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 914:169812. [PMID: 38181942 DOI: 10.1016/j.scitotenv.2023.169812] [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: 10/19/2023] [Revised: 12/28/2023] [Accepted: 12/29/2023] [Indexed: 01/07/2024]
Abstract
The present study examined the defense responses of toxigenic Pseudo-nitzschia species (P. multiseries) to a mixotrophic dinoflagellate, Lepidodinium sp., and its associated cues. We evaluated their responses to different predation risks, including direct physical contact and indirect interactions facilitated by cues from Lepidodinium sp. during active feeding on heterospecific prey (Rhodonomas salina), limited feeding on conspecific prey (P. multiseries) and non-feeding (autotrophic growth in f/2 medium) states. This study is the first investigation of these trophic interactions. Our results demonstrated a significant increase in cellular domoic acid (cDA) in P. multiseries when exposed to Lepidodinium sp. and its associated cues, which was 1.38 to 2.42 times higher than the non-induced group. Notably, this increase was observed regardless of Lepidodinium sp. feeding on this toxic diatom and nutritional modes. However, the most significant increase occurred when they directly interacted. These findings suggest that P. multiseries evaluates predation risk and increases cDA production as a defensive strategy against potential grazing threats. No morphological changes were observed in P. multiseries in response to Lepidodinium sp. or its cues. P. multiseries cultured in flasks of Group L+P-P showed a decrease in growth, but Group L-P and Group L+R-P did not exhibit any decrease. These results suggest a lack of consistent trade-offs between the defense response and growth, thus an increase in cDA production may be a sustainable and efficient defense strategy for P. multiseries. Furthermore, our findings indicate that P. multiseries had no significant impact on the fitness (cell size, growth and/or grazing) of Lepidodinium sp. and R. salina, which suggests no evident toxic or allelopathic impacts on these two phytoplankton species. This study enhances our understanding of the trophic interactions between toxic diatoms and mixotrophic dinoflagellates and helps elucidate the dynamics of Harmful Algal Blooms, toxin transmission, and their impact on ecosystem health.
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Affiliation(s)
- Shuwen Zhang
- Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, South China Normal University, Guangzhou 510631, PR China
| | - Tingting Zheng
- Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, South China Normal University, Guangzhou 510631, PR China
| | - Muyao Zhou
- Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, South China Normal University, Guangzhou 510631, PR China
| | - Biaobiao Niu
- Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, South China Normal University, Guangzhou 510631, PR China
| | - Yang Li
- Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, South China Normal University, Guangzhou 510631, PR China.
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Cadaillon AM, Mattera B, Albizzi A, Montoya N, Maldonado S, Raya Rey A, Riccialdelli L, Almandoz GO, Schloss IR. Multispecies mass mortality in the Beagle Channel associated with paralytic shellfish toxins. HARMFUL ALGAE 2024; 132:102581. [PMID: 38331545 DOI: 10.1016/j.hal.2024.102581] [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: 09/06/2023] [Revised: 12/06/2023] [Accepted: 01/10/2024] [Indexed: 02/10/2024]
Abstract
The Beagle Channel is a Subantarctic semi-estuarine environment at the southern tip of South America, where intoxication events associated with harmful algal blooms have been reported since 1886, including a world record in toxicity due to Alexandrium catenella in 1992. Toxic algae affect public health and ecosystem services, particularly mussel aquaculture and fisheries management. During the austral summer of 2022, an intense bloom of A. catenella (5 × 104 cells L-1) occurred in the Beagle Channel, leading to the second most toxic event in the area, with mussel toxicity reaching 197,266 µg STXeq kg-1. This event was synchronous with the mortality of marine organisms from different trophic levels and terrestrial fauna, i.e., two Fuegian red foxes and a southern caracara. Stomach content and liver samples from dead kelp gulls (Larus dominicanus), Magellanic penguins (Spheniscus magellanicus), papua penguins (Pygoscelis papua), and imperial cormorants (Leucocarbo atriceps), presented variable paralytic shellfish toxins (PST) levels (up to 3427 µg STXeq kg-1) as measured by high performance liquid chromatography (HPLC), suggesting that deaths were associated with high PST toxicity level. The different toxin profiles found in phytoplankton, zooplankton, squat lobsters (Grimothea gregaria), Fuegian sprat (Sprattus fuegensis), and seabirds evidenced possible toxin transformation along the food web and the possible transfer vectors. The unexpected detection of PST in terrestrial fauna (up to 2707 µg STXeq kg-1) suggested intoxication by scavenging on squat lobsters, which had high toxicity (26,663 µg STXeq kg-1). PST trace levels were also detected in a liver sample of a dead false killer whale (Pseudorca crassidens), an oceanic odontocete stranded on the coast during the bloom. Overall, our results denote the exceptional nature of the toxic, multispecies mortality event and that toxins may propagate to several levels of the food web in this Subantarctic environment.
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Affiliation(s)
- A M Cadaillon
- Centro Austral de Investigaciones Científicas (CADIC) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bernardo Houssay 200, Ushuaia, Argentina; Instituto de Desarrollo Económico e Innovación (IDEI), Universidad Nacional de Tierra del Fuego, Antártida e Islas del Atlántico Sur (UNTDF), Yrigoyen 879, Ushuaia 9410, Argentina.
| | - B Mattera
- Instituto Nacional de Investigación y Desarrollo Pesquero, Paseo Victoria Ocampo N°1, Mar del Plata 7600, Argentina
| | - A Albizzi
- Centro Austral de Investigaciones Científicas (CADIC) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bernardo Houssay 200, Ushuaia, Argentina
| | - N Montoya
- Instituto Nacional de Investigación y Desarrollo Pesquero, Paseo Victoria Ocampo N°1, Mar del Plata 7600, Argentina
| | - S Maldonado
- Dirección General de Laboratorio de Toxinas y Microbiología, Secretaría de Pesca y Acuicultura, Ministerio de Produccion y Ambiente. Gobierno de la Provincia de Tierra del Fuego, Antártida e Islas del Atlántico Sur, Argentina
| | - A Raya Rey
- Centro Austral de Investigaciones Científicas (CADIC) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bernardo Houssay 200, Ushuaia, Argentina; Instituto de Ciencias Polares, Ambiente y Recursos Naturales (ICPA), UNTDF, Yrigoyen 879, Ushuaia 9410, Argentina; Wildlife Conservation Society, Amenábar 1595, Office 19, C1426AKC CABA, Buenos Aires, Argentina
| | - L Riccialdelli
- Centro Austral de Investigaciones Científicas (CADIC) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bernardo Houssay 200, Ushuaia, Argentina
| | - G O Almandoz
- División Ficología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, B1900FWA La Plata, Argentina; CONICET, Godoy Cruz 2290 (C1425FQB), Ciudad Autónoma de Buenos Aires, Argentina
| | - I R Schloss
- Centro Austral de Investigaciones Científicas (CADIC) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bernardo Houssay 200, Ushuaia, Argentina; Instituto de Ciencias Polares, Ambiente y Recursos Naturales (ICPA), UNTDF, Yrigoyen 879, Ushuaia 9410, Argentina; Instituto Antártico Argentino, Buenos Aires, Argentina
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3
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Kiørboe T. Predation in a Microbial World: Mechanisms and Trade-Offs of Flagellate Foraging. ANNUAL REVIEW OF MARINE SCIENCE 2024; 16:361-381. [PMID: 37368955 DOI: 10.1146/annurev-marine-020123-102001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/29/2023]
Abstract
Heterotrophic nanoflagellates are the main consumers of bacteria and picophytoplankton in the ocean and thus play a key role in ocean biogeochemistry. They are found in all major branches of the eukaryotic tree of life but are united by all being equipped with one or a few flagella that they use to generate a feeding current. These microbial predators are faced with the challenges that viscosity at this small scale impedes predator-prey contact and that their foraging activity disturbs the ambient water and thus attracts their own flow-sensing predators. Here, I describe some of the diverse adaptations of the flagellum to produce sufficient force to overcome viscosity and of the flagellar arrangement to minimize fluid disturbances, and thus of the various solutions to optimize the foraging-predation risk trade-off. I demonstrate how insights into this trade-off can be used to develop robust trait-based models of microbial food webs.
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Affiliation(s)
- Thomas Kiørboe
- Centre for Ocean Life, DTU Aqua, Technical University of Denmark, Kongens Lyngby, Denmark;
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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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Nwankwegu AS, Zhang L, Xie D, Ohore OE, Li Y, Yang G, Yao X, Song Z, Yang Q. Metabolites dynamics exacerbated by external nutrients inputs into a Ceratium hirundinella-dominated bloom in the Pengxi River, Three Gorges Reservoir, China. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2023; 258:106507. [PMID: 36965430 DOI: 10.1016/j.aquatox.2023.106507] [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: 11/01/2022] [Revised: 03/20/2023] [Accepted: 03/21/2023] [Indexed: 06/18/2023]
Abstract
Secondary metabolites (toxins) production during harmful algal blooms (HABs) further increases the public health risks associated with water quality deterioration from anthropogenic eutrophication. In the present study, the dynamic pattern in the production of metabolites under different nutrient conditions in Ceratium-dominated spring HABs was investigated in Pengxi River, China. Results revealed five (5) important toxins all attributable to the Dinophyceae including azaspiracid 2&4, okadaic acid, tetrodotoxin, brevetoxin, and saxitoxin, each exhibiting certain levels of specificity to the ecosystem enrichments. In effect, while the production of azaspiracid 2 and okadaic acid was N-driven, azaspiracid 4 and tetrodotoxin were enhanced by Ca enrichment. The ambient HABs community structure shows absolute ecosystem dominance by a dinoflagellate, Ceratium hirundinella with relative abundance ((RA = 78.81%, p ˂ 0.05). However, P enrichment triggered a slight shift (p ≥ 0.05) in the HABs species structure within the cyanobacteria strictly represented by Chroococcus minor (RA = 26.60%) and Dolichospermum circinalis (RA = 23.91%) initiating possible emergency dominance. The effect of nutrient addition on biomass production as chlorophyll-a (Chl-a) confirmed a P-limited ecosystem juxtaposed by a secondary limitation by Ca. The significant stimulation on biomass as Chl-a from day 3 through day 4 by N and the multiple enrichments designated as NPFeCa was attributed to luxury consumption rather than limitation following N repletion thus delaying biomass accumulation. The study, therefore, offers useful insights into the dynamic pattern of toxins during spring HABs while it also provides comprehensive knowledge of the HABs impact predictions in the TGR.
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Affiliation(s)
- Amechi S Nwankwegu
- College of Resources and Environment, Southwest University, 1 Tiansheng Road, Beibei District, Chongqing 400716 China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in Three Gorges Reservoir Region, Chongqing 400716 China; College of Environment, Hohai University, No. 1 Xikang Road, Gulou District, Nanjing 210098, China
| | - Lei Zhang
- College of Resources and Environment, Southwest University, 1 Tiansheng Road, Beibei District, Chongqing 400716 China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in Three Gorges Reservoir Region, Chongqing 400716 China.
| | - Deti Xie
- College of Resources and Environment, Southwest University, 1 Tiansheng Road, Beibei District, Chongqing 400716 China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in Three Gorges Reservoir Region, Chongqing 400716 China.
| | - Okugbe E Ohore
- Institute of Marine Sciences, Shantou University, Shantou 515063, China
| | - Yiping Li
- College of Environment, Hohai University, No. 1 Xikang Road, Gulou District, Nanjing 210098, China
| | - Guanglang Yang
- College of Resources and Environment, Southwest University, 1 Tiansheng Road, Beibei District, Chongqing 400716 China
| | - Xuexing Yao
- College of Resources and Environment, Southwest University, 1 Tiansheng Road, Beibei District, Chongqing 400716 China
| | - Zenghui Song
- College of Resources and Environment, Southwest University, 1 Tiansheng Road, Beibei District, Chongqing 400716 China
| | - Qing Yang
- College of Resources and Environment, Southwest University, 1 Tiansheng Road, Beibei District, Chongqing 400716 China
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Berry O, Briand E, Bagot A, Chaigné M, Meslet-Cladière L, Wang J, Grovel O, Jansen JJ, Ruiz N, du Pont TR, Pouchus YF, Hess P, Bertrand S. Deciphering interactions between the marine dinoflagellate Prorocentrum lima and the fungus Aspergillus pseudoglaucus. Environ Microbiol 2023; 25:250-267. [PMID: 36333915 PMCID: PMC10100339 DOI: 10.1111/1462-2920.16271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 10/28/2022] [Indexed: 11/07/2022]
Abstract
The comprehension of microbial interactions is one of the key challenges in marine microbial ecology. This study focused on exploring chemical interactions between the toxic dinoflagellate Prorocentrum lima and a filamentous fungal species, Aspergillus pseudoglaucus, which has been isolated from the microalgal culture. Such interspecies interactions are expected to occur even though they were rarely studied. Here, a co-culture system was designed in a dedicated microscale marine-like condition. This system allowed to explore microalgal-fungal physical and metabolic interactions in presence and absence of the bacterial consortium. Microscopic observation showed an unusual physical contact between the fungal mycelium and dinoflagellate cells. To delineate specialized metabolome alterations during microalgal-fungal co-culture metabolomes were monitored by high-performance liquid chromatography coupled to high-resolution mass spectrometry. In-depth multivariate statistical analysis using dedicated approaches highlighted (1) the metabolic alterations associated with microalgal-fungal co-culture, and (2) the impact of associated bacteria in microalgal metabolome response to fungal interaction. Unfortunately, only a very low number of highlighted features were fully characterized. However, an up-regulation of the dinoflagellate toxins okadaic acid and dinophysistoxin 1 was observed during co-culture in supernatants. Such results highlight the importance to consider microalgal-fungal interactions in the study of parameters regulating toxin production.
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Affiliation(s)
- Olivier Berry
- Institut des Substances et Organismes de la Mer, ISOMer, Nantes Université, UR 2160, Nantes, France
| | | | - Alizé Bagot
- Institut des Substances et Organismes de la Mer, ISOMer, Nantes Université, UR 2160, Nantes, France
- IFREMER, PHYTOX, Nantes, France
| | - Maud Chaigné
- Institut des Substances et Organismes de la Mer, ISOMer, Nantes Université, UR 2160, Nantes, France
- IFREMER, PHYTOX, Nantes, France
| | - Laurence Meslet-Cladière
- Univ Brest, INRAE, Laboratoire Universitaire de Biodiversité et Écologie Microbienne, Plouzané, France
| | - Julien Wang
- Institut des Substances et Organismes de la Mer, ISOMer, Nantes Université, UR 2160, Nantes, France
| | - Olivier Grovel
- Institut des Substances et Organismes de la Mer, ISOMer, Nantes Université, UR 2160, Nantes, France
| | - Jeroen J Jansen
- Radboud University, Institute for Molecules and Materials, Nijmegen, The Netherlands
| | - Nicolas Ruiz
- Institut des Substances et Organismes de la Mer, ISOMer, Nantes Université, UR 2160, Nantes, France
| | - Thibaut Robiou du Pont
- Institut des Substances et Organismes de la Mer, ISOMer, Nantes Université, UR 2160, Nantes, France
| | - Yves François Pouchus
- Institut des Substances et Organismes de la Mer, ISOMer, Nantes Université, UR 2160, Nantes, France
| | | | - Samuel Bertrand
- Institut des Substances et Organismes de la Mer, ISOMer, Nantes Université, UR 2160, Nantes, France
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Hwang J, Kang HW, Moon SJ, Hyung JH, Lee ES, Park J. Metagenomic Analysis of the Species Composition and Seasonal Distribution of Marine Dinoflagellate Communities in Four Korean Coastal Regions. Microorganisms 2022; 10:microorganisms10071459. [PMID: 35889179 PMCID: PMC9320301 DOI: 10.3390/microorganisms10071459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 07/14/2022] [Accepted: 07/18/2022] [Indexed: 12/10/2022] Open
Abstract
Biomonitoring of dinoflagellate communities in marine ecosystems is essential for efficient water quality management and limiting ecosystem disturbances. Current identification and monitoring of toxic dinoflagellates, which cause harmful algal blooms, primarily involves light or scanning electron microscopy; however, these techniques are limited in their ability to monitor dinoflagellates and plankton, leaving an incomplete analysis. In this study, we analyzed the species composition and seasonal distribution of the dinoflagellate communities in four Korean coastal regions using 18S rRNA amplicon sequencing. The results showed significantly high diversity in the dinoflagellate communities in all regions and seasons. Furthermore, we found seasonally dominant species and causative species of harmful algal blooms (Cochlodinium sp., Alexandrium sp., Dinophysis sp., and Gymnodinium sp.). Moreover, dominant species were classified by region and season according to the difference in geographical and environmental parameters. The molecular analysis of the dinoflagellate community based on metagenomics revealed more diverse species compositions that could not be identified by microscopy and revealed potentially harmful or recently introduced dinoflagellate species. In conclusion, metagenomic analysis of dinoflagellate communities was more precise and obtained results faster than microscopic analysis, and could improve the existing monitoring techniques for community analysis.
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Affiliation(s)
- Jinik Hwang
- West Sea Fisheries Research Institute, National Institute of Fisheries Science, Incheon 22383, Korea; (J.H.); (H.W.K.)
| | - Hee Woong Kang
- West Sea Fisheries Research Institute, National Institute of Fisheries Science, Incheon 22383, Korea; (J.H.); (H.W.K.)
| | - Seung Joo Moon
- Environment and Resource Convergence Center, Advanced Institute of Convergence Technology, Suwon 16229, Korea; (S.J.M.); (J.-H.H.); (E.S.L.)
| | - Jun-Ho Hyung
- Environment and Resource Convergence Center, Advanced Institute of Convergence Technology, Suwon 16229, Korea; (S.J.M.); (J.-H.H.); (E.S.L.)
| | - Eun Sun Lee
- Environment and Resource Convergence Center, Advanced Institute of Convergence Technology, Suwon 16229, Korea; (S.J.M.); (J.-H.H.); (E.S.L.)
| | - Jaeyeon Park
- Environment and Resource Convergence Center, Advanced Institute of Convergence Technology, Suwon 16229, Korea; (S.J.M.); (J.-H.H.); (E.S.L.)
- Correspondence: ; Tel.: +82-31-888-9042; Fax: +82-31-888-9040
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Tang Z, Qiu J, Wang G, Ji Y, Hess P, Li A. Development of an Efficient Extraction Method for Harvesting Gymnodimine-A from Large-Scale Cultures of Karenia selliformis. Toxins (Basel) 2021; 13:793. [PMID: 34822577 PMCID: PMC8621799 DOI: 10.3390/toxins13110793] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 11/23/2022] Open
Abstract
Gymnodimine-A (GYM-A) is a fast-acting microalgal toxin and its production of certified materials requires an efficient harvesting technology from the large-scale cultures of toxigenic microalgae. In this study the recoveries of GYM-A were compared between several liquid-liquid extraction (LLE) treatments including solvents, ratios and stirring times to optimize the LLE technique for harvesting GYM-A from Karenia selliformis cultures, of which the dichloromethane was selected as the extractant and added to microalgal cultures at the ratio 55 mL L-1 (5.5%, v/v). The recovery of GYM-A obtained by the LLE technique was also compared with filtration and centrifugation methods. The stability of GYM-A in culture media were also tested under different pH conditions. Results showed that both the conventional filter filtration and centrifugation methods led to fragmentation of microalgal cells and loss of GYM-A in the harvesting processes. A total of 5.1 µg of GYM-A were obtained from 2 L of K. selliformis cultures with a satisfactory recovery of 88%. Interestingly, GYM-A obviously degraded in the culture media with the initial pH 8.2 and the adjusted pH of 7.0 after 7 days, but there was no obvious degradation in the acidic medium at pH 5.0. Therefore, the LLE method developed here permits the collection of large-volume cultures of K. selliformis and the high-efficiency extraction of GYM-A. This work provides a simple and valuable technique for harvesting toxins from large-scale cultures of GYM-producing microalgae.
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Affiliation(s)
- Zhixuan Tang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; (Z.T.); (J.Q.); (G.W.); (Y.J.)
- Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao 266100, China
| | - Jiangbing Qiu
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; (Z.T.); (J.Q.); (G.W.); (Y.J.)
- Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao 266100, China
| | - Guixiang Wang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; (Z.T.); (J.Q.); (G.W.); (Y.J.)
- Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao 266100, China
| | - Ying Ji
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; (Z.T.); (J.Q.); (G.W.); (Y.J.)
- Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao 266100, China
| | - Philipp Hess
- Ifremer, DYNECO, Phycotoxins Laboratory, F-44000 Nantes, France;
| | - Aifeng Li
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; (Z.T.); (J.Q.); (G.W.); (Y.J.)
- Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao 266100, China
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Vilar MCP, da Costa Pena Rodrigues TF, da Silva Ferrão-Filho A, de Oliveira E Azevedo SMF. Grazer-Induced Chemical Defense in a Microcystin-Producing Microcystis aeruginosa (Cyanobacteria) Exposed to Daphnia gessneri Infochemicals. J Chem Ecol 2021; 47:847-858. [PMID: 34569003 DOI: 10.1007/s10886-021-01315-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/09/2021] [Accepted: 09/14/2021] [Indexed: 10/20/2022]
Abstract
Cyanobacteria are photosynthetic microorganisms that compose phytoplankton and therefore have a trophic relationship with zooplankton, which represent an important link for energy flux in aquatic food webs. Several species can form blooms and produce bioactive metabolites known as cyanotoxins. However, the ecological and adaptative role of these toxins are still under debate. Many studies have addressed the cyanotoxins' function in defense against herbivory when grazing pressure by zooplankton plays a role in phytoplankton top-down control. Thus, the present study evaluated the ecophysiological responses of the cyanobacterial strain Microcystis aeruginosa NPLJ-4 underlying the chemical induced defense against the cladoceran Daphnia gessneri. Exposure to predator infochemicals consisted of cultures established in ASM-1 medium prepared in a filtrate from a culture of adults of D. gessneri at an environmentally relevant density. Daphnia infochemicals promoted a significant increase in toxin production by M. aeruginosa. However, no differences in growth were observed, despite a significant increase in both maximum photosynthetic efficiency and electron transport rate in response to zooplankton. Additionally, there was no significant variation in the production of exopolysaccharides. Overall, although a grazer-induced defense response was demonstrated, there were no effects on M. aeruginosa fitness, which maintained its growth in the presence of Daphnia alarm cues.
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Affiliation(s)
- Mauro Cesar Palmeira Vilar
- Laboratory of Ecophysiology and Toxicology of Cyanobacteria, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, 21949-902, Brazil.
| | - Thiago Ferreira da Costa Pena Rodrigues
- Laboratory of Ecophysiology and Toxicology of Cyanobacteria, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, 21949-902, Brazil
| | - Aloysio da Silva Ferrão-Filho
- Laboratory of Evaluation and Promotion of Environmental Health, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, RJ, 21040-360, Brazil
| | - Sandra Maria Feliciano de Oliveira E Azevedo
- Laboratory of Ecophysiology and Toxicology of Cyanobacteria, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, 21949-902, Brazil
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10
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Insights into Alexandrium minutum Nutrient Acquisition, Metabolism and Saxitoxin Biosynthesis through Comprehensive Transcriptome Survey. BIOLOGY 2021; 10:biology10090826. [PMID: 34571703 PMCID: PMC8465370 DOI: 10.3390/biology10090826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/12/2021] [Accepted: 08/13/2021] [Indexed: 11/17/2022]
Abstract
Simple Summary Alexandrium minutum is one of the causing organisms for the occurrence of harmful algae bloom (HABs) in marine ecosystems. This species produces saxitoxin, one of the deadliest neurotoxins which can cause human mortality. However, molecular information such as genes and proteins catalog on this species is still lacking. Therefore, this study has successfully characterized several new molecular mechanisms regarding A. minutum environmental adaptation and saxitoxin biosynthesis. Ultimately, this study provides a valuable resource for facilitating future dinoflagellates’ molecular response to environmental changes. Abstract The toxin-producing dinoflagellate Alexandrium minutum is responsible for the outbreaks of harmful algae bloom (HABs). It is a widely distributed species and is responsible for producing paralytic shellfish poisoning toxins. However, the information associated with the environmental adaptation pathway and toxin biosynthesis in this species is still lacking. Therefore, this study focuses on the functional characterization of A. minutum unigenes obtained from transcriptome sequencing using the Illumina Hiseq 4000 sequencing platform. A total of 58,802 (47.05%) unigenes were successfully annotated using public databases such as NCBI-Nr, UniprotKB, EggNOG, KEGG, InterPRO and Gene Ontology (GO). This study has successfully identified key features that enable A. minutum to adapt to the marine environment, including several carbon metabolic pathways, assimilation of various sources of nitrogen and phosphorus. A. minutum was found to encode homologues for several proteins involved in saxitoxin biosynthesis, including the first three proteins in the pathway of saxitoxin biosynthesis, namely sxtA, sxtG and sxtB. The comprehensive transcriptome analysis presented in this study represents a valuable resource for understanding the dinoflagellates molecular metabolic model regarding nutrient acquisition and biosynthesis of saxitoxin.
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11
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Gummaa NR, Dwaish AS, Hamzah IH. Molecular detection of some toxogenic cyanobacteria in Tigris River in Baghdad-Iraq. Mol Biol Rep 2021; 48:5393-5397. [PMID: 34283333 DOI: 10.1007/s11033-021-06538-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/30/2021] [Indexed: 11/29/2022]
Abstract
Cyanobacteria and their pollution are being increasingly commonly reported worldwide that cause a serious hazard to environmental and human health. Cyanotoxin was the most algal toxin reported to be produced by several orders of cyanobacteria. This study aimed to provide a technique to detect cylindrosprmopsin and saxitoxin biosynthesis genes in the river. In November, December 2019, and January 2020. Cyanobacteria were isolated from freshwater of Tigris River and identified by compound microscope also conventional PCR. Five isolates of cyanobacteria that successfully amplified a gene fragment from the phycocyanin were found in all cyanobacteria (Microcystis flosaquae, Microcystis sp, anabaena circinalis, nostoc commune and westiellopsis prolifica) and all isolates successfully amplified aoaC gene to detecting the cylidrospemopsin and the saxitoxin. Our results concluded that PCR assay can be used for early detection of cylidrospemopsin and the saxitoxin producing cyanobacteria in river water that useful to stations responsible for the preparation of drinking water to public.
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Affiliation(s)
- Noor Redha Gummaa
- Biology Department, College of Science, Mustansiriyah University, Baghdad, Iraq
| | - Ahmed Sahi Dwaish
- Biology Department, College of Science, Mustansiriyah University, Baghdad, Iraq
| | - Israa Hussein Hamzah
- Biology Department, College of Science, Mustansiriyah University, Baghdad, Iraq.
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12
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Ryderheim F, Selander E, Kiørboe T. Predator-induced defence in a dinoflagellate generates benefits without direct costs. THE ISME JOURNAL 2021; 15:2107-2116. [PMID: 33580210 PMCID: PMC8245491 DOI: 10.1038/s41396-021-00908-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 01/19/2021] [Accepted: 01/21/2021] [Indexed: 01/31/2023]
Abstract
Inducible defences in phytoplankton are often assumed to come at a cost to the organism, but trade-offs have proven hard to establish experimentally. A reason for this may be that some trade-off costs only become evident under resource-limiting conditions. To explore the effect of nutrient limitation on trade-offs in toxin-producing dinoflagellates, we induced toxin production in Alexandrium minutum by chemical cues from copepods under different levels of nitrogen limitation. The effects were both nitrogen- and grazer-concentration dependent. Induced cells had higher cellular toxin content and a larger fraction of the cells was rejected by a copepod, demonstrating the clear benefits of toxin production. Induced cells also had a higher carbon and nitrogen content, despite up to 25% reduction in cell size. Unexpectedly, induced cells seemed to grow faster than controls, likely owing to a higher specific nutrient affinity due to reduced size. We thus found no clear trade-offs, rather the opposite. However, indirect ecological costs that do not manifest under laboratory conditions may be important. Inducing appropriate defence traits in response to threat-specific warning signals may also prevent larger cumulative costs from expressing several defensive traits simultaneously.
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Affiliation(s)
- Fredrik Ryderheim
- Centre for Ocean Life, DTU Aqua, Technical University of Denmark, Lyngby, Denmark.
| | - Erik Selander
- Department of Marine Sciences, University of Gothenburg, Göteborg, Sweden
| | - Thomas Kiørboe
- Centre for Ocean Life, DTU Aqua, Technical University of Denmark, Lyngby, Denmark
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13
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Śliwińska-Wilczewska S, Wiśniewska K, Konarzewska Z, Cieszyńska A, Barreiro Felpeto A, Lewandowska AU, Latała A. The current state of knowledge on taxonomy, modulating factors, ecological roles, and mode of action of phytoplankton allelochemicals. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 773:145681. [PMID: 33940759 DOI: 10.1016/j.scitotenv.2021.145681] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 01/09/2021] [Accepted: 02/03/2021] [Indexed: 06/12/2023]
Abstract
Allelopathy is widespread in marine, brackish, and freshwater habitats. Literature data indicate that allelopathy could offer a competitive advantage for some phytoplankton species by reducing the growth of competitors. It is also believed that allelopathy may affect species succession. Thus, allelopathy may play a role in the development of blooms. Over the past few decades, the world's coastal waters have experienced increases in the numbers of cyanobacterial and microalgal blooming events. Understanding how allelopathy is implicated with other biological and environmental factors as a bloom-development mechanism is an important topic for future research. This review focuses on a taxonomic overview of allelopathic cyanobacteria and microalgae, the biological and environmental factors that affect allelochemical production, their role in ecological dynamics, and their physiological modes of action, as well as potential industrial applications of allelopathic compounds.
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Affiliation(s)
- Sylwia Śliwińska-Wilczewska
- Division of Marine Ecosystems Functioning, Institute of Oceanography, University of Gdańsk, Av. Piłsudskiego 46, 81-378 Gdynia, Poland.
| | - Kinga Wiśniewska
- Division of Marine Chemistry and Environmental Protection, Institute of Oceanography, University of Gdańsk, Av. Piłsudskiego 46, 81-378 Gdynia, Poland
| | - Zofia Konarzewska
- Division of Marine Ecosystems Functioning, Institute of Oceanography, University of Gdańsk, Av. Piłsudskiego 46, 81-378 Gdynia, Poland
| | - Agata Cieszyńska
- Institute of Oceanology Polish Academy of Sciences, Department of Marine Physics, Marine Biophysics Laboratory, Sopot, Poland
| | - Aldo Barreiro Felpeto
- Interdisciplinary Center of Marine and Environmental Research-CIMAR/CIIMAR, University of Porto, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal
| | - Anita U Lewandowska
- Division of Marine Chemistry and Environmental Protection, Institute of Oceanography, University of Gdańsk, Av. Piłsudskiego 46, 81-378 Gdynia, Poland
| | - Adam Latała
- Division of Marine Ecosystems Functioning, Institute of Oceanography, University of Gdańsk, Av. Piłsudskiego 46, 81-378 Gdynia, Poland
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14
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Park G, Dam HG. Cell-growth gene expression reveals a direct fitness cost of grazer-induced toxin production in red tide dinoflagellate prey. Proc Biol Sci 2021; 288:20202480. [PMID: 33563117 DOI: 10.1098/rspb.2020.2480] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Induced prey defences against consumers are conspicuous in microbes, plants and animals. In toxigenic prey, a defence fitness cost should result in a trade-off between defence expression and individual growth. Yet, previous experimental work has failed to detect such induced defence cost in toxigenic phytoplankton. We measured a potential direct fitness cost of grazer-induced toxin production in a red tide dinoflagellate prey using relative gene expression (RGE) of a mitotic cyclin gene (cyc), a marker that correlates to cell growth. This approach disentangles the reduction in cell growth from the defence cost from the mortality by consumers. Treatments where the dinoflagellate Alexandrium catenella were exposed to copepod grazers significantly increased toxin production while decreasing RGE of cyc, indicating a defence-growth trade-off. The defence fitness cost represents a mean decrease of the cell growth rate of 32%. Simultaneously, we estimate that the traditional method to measure mortality loss by consumers is overestimated by 29%. The defence appears adaptive as the prey population persists in quasi steady state after the defence is induced. Our approach provides a novel framework to incorporate the fitness cost of defence in toxigenic prey-consumer interaction models.
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Affiliation(s)
- Gihong Park
- Department of Marine Sciences, University of Connecticut, 1080 Shennecossett Road, Groton, CT 06340, USA
| | - Hans G Dam
- Department of Marine Sciences, University of Connecticut, 1080 Shennecossett Road, Groton, CT 06340, USA
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15
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Cusick KD, Widder EA. Bioluminescence and toxicity as driving factors in harmful algal blooms: Ecological functions and genetic variability. HARMFUL ALGAE 2020; 98:101850. [PMID: 33129462 DOI: 10.1016/j.hal.2020.101850] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 05/29/2020] [Accepted: 06/02/2020] [Indexed: 06/11/2023]
Abstract
Dinoflagellates are an ecologically important group of marine microbial eukaryotes with a remarkable array of adaptive strategies. It is ironic that two of the traits for which dinoflagellates are best known, toxin production and bioluminescence, are rarely linked when considering the ecological significance of either. Although dinoflagellate species that form some of the most widespread and frequent harmful algal blooms (HABs) are bioluminescent, the molecular and eco-evolutionary associations between these two traits has received little attention. Here, the major themes of biochemistry and genetics, ecological functions, signaling mechanisms, and evolution are addressed, with parallels and connections drawn between the two. Of the 17 major classes of dinoflagellate toxins, only two are produced by bioluminescent species: saxitoxin (STX) and yessotoxin. Of these, STX has been extensively studied, including the identification of the STX biosynthetic genes. While numerous theories have been put forward as to the eco-evolutionary roles of both bioluminescence and toxicity, a general consensus is that both function as grazing deterrents. Thus, both bioluminescence and toxicity may aid in HAB initiation as they alleviate grazing pressure on the HAB species. A large gap in our understanding is the genetic variability among natural bloom populations, as both toxic and non-toxic strains have been isolated from the same geographic location. The same applies to bioluminescence, as there exist both bioluminescent and non-bioluminescent strains of the same species. Recent evidence demonstrating that blooms are not monoclonal events necessitates a greater level of understanding as to the genetic variability of these traits among sub-populations as well as the mechanisms by which cells acquire or lose the trait, as sequence analysis of STX+ and STX- species indicate the key gene required for toxicity is lost rather than gained. While the extent of genetic variability for both bioluminescence and toxicity among natural HAB sub-populations remains unknown, it is an area that needs to be explored in order to gain greater insights into the molecular mechanisms and environmental parameters driving HAB evolution.
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Affiliation(s)
- Kathleen D Cusick
- University of Maryland Baltimore County, Department of Biological Sciences, 1000 Hilltop Circle, Baltimore, MD 21250, United States.
| | - Edith A Widder
- Ocean Research and Conservation Association, 1420 Seaway Dr, Fort Pierce, FL 34949, United States.
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16
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Matthews B, Jokela J, Narwani A, Räsänen K, Pomati F, Altermatt F, Spaak P, Robinson CT, Vorburger C. On biological evolution and environmental solutions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 724:138194. [PMID: 32251887 PMCID: PMC7118648 DOI: 10.1016/j.scitotenv.2020.138194] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 03/23/2020] [Accepted: 03/23/2020] [Indexed: 05/22/2023]
Abstract
Drawing insights from multiple disciplines is essential for finding integrative solutions that are required to tackle complex environmental problems. Human activities are causing unprecedented influence on global ecosystems, culminating in the loss of species and fundamental changes in the selective environments of organisms across the tree of life. Our collective understanding about biological evolution can help identify and mitigate many of the environmental problems in the Anthropocene. To this end, we propose a stronger integration of environmental sciences with evolutionary biology.
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Affiliation(s)
- Blake Matthews
- EAWAG, Department of Fish Ecology and Evolution, Center for Ecology, Evolution, and Biogeochemistry, Seestrasse 79, 6047 Kastanienbaum, Switzerland; EAWAG, Department of Aquatic Ecology, Überlandstr. 133, 8600 Dübendorf, Switzerland; Institute of Integrative Biology, ETH-Zurich, Zurich, Switzerland.
| | - Jukka Jokela
- EAWAG, Department of Aquatic Ecology, Überlandstr. 133, 8600 Dübendorf, Switzerland; Institute of Integrative Biology, ETH-Zurich, Zurich, Switzerland
| | - Anita Narwani
- EAWAG, Department of Aquatic Ecology, Überlandstr. 133, 8600 Dübendorf, Switzerland; Institute of Integrative Biology, ETH-Zurich, Zurich, Switzerland
| | - Katja Räsänen
- EAWAG, Department of Aquatic Ecology, Überlandstr. 133, 8600 Dübendorf, Switzerland; Institute of Integrative Biology, ETH-Zurich, Zurich, Switzerland
| | - Francesco Pomati
- EAWAG, Department of Aquatic Ecology, Überlandstr. 133, 8600 Dübendorf, Switzerland; Institute of Integrative Biology, ETH-Zurich, Zurich, Switzerland
| | - Florian Altermatt
- EAWAG, Department of Aquatic Ecology, Überlandstr. 133, 8600 Dübendorf, Switzerland; Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Piet Spaak
- EAWAG, Department of Aquatic Ecology, Überlandstr. 133, 8600 Dübendorf, Switzerland; Institute of Integrative Biology, ETH-Zurich, Zurich, Switzerland
| | | | - Christoph Vorburger
- EAWAG, Department of Aquatic Ecology, Überlandstr. 133, 8600 Dübendorf, Switzerland; Institute of Integrative Biology, ETH-Zurich, Zurich, Switzerland.
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17
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Effects of Nutrient Limitation on the Synthesis of N-Rich Phytoplankton Toxins: A Meta-Analysis. Toxins (Basel) 2020; 12:toxins12040221. [PMID: 32244741 PMCID: PMC7232484 DOI: 10.3390/toxins12040221] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 03/11/2020] [Accepted: 03/12/2020] [Indexed: 11/21/2022] Open
Abstract
Eutrophication has played a major role in the worldwide increase of harmful algal blooms (HABs). Higher input of key nutrients, such as nitrogen (N) and phosphorus (P), can stimulate the growth of harmful algal species in freshwater, estuarine, and coastal marine ecosystems. Some HAB-forming taxa, particularly several cyanobacteria and dinoflagellate species, are harmful through the production of N-rich toxins that have detrimental effects on the environment and human health. Here, we test how changes in nutrient availability affect N-rich toxin synthesis in cyanobacteria and dinoflagellates using a meta-analysis approach. Overall, N-rich toxin content showed an increase with P limitation, while it tended to decrease with N limitation, but we also observed substantial variation in responses both within and across genera and toxin groups. For instance, in response to N limitation, microcystin content varied from a 297% decrease up to a 273% increase, and paralytic shellfish poisoning (PSP) toxin content varied from a 204% decrease to an 82% increase. Cylindrospermopsin, produced by N2-fixing cyanobacteria, showed no clear direction in response to nutrient limitation, and cellular contents of this compound may thus vary independently of nutrient fluctuations. Our results confirm earlier reported stoichiometric regulation of N-rich phytoplankton toxins, showing increased toxin content with an increase in cellular N:P ratios, and vice versa. Thus, changes in N-rich toxin content largely follow the changes in relative cellular N content. Consequently, although nutrient limitation may limit bloom biomass and thereby bloom toxicity, our results warn that P limitation can cause accumulation of cellular toxins and thus lead to unexpected increases in bloom toxicity.
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18
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Blossom HE, Markussen B, Daugbjerg N, Krock B, Norlin A, Hansen PJ. The Cost of Toxicity in Microalgae: Direct Evidence From the Dinoflagellate Alexandrium. Front Microbiol 2019; 10:1065. [PMID: 31178832 PMCID: PMC6538772 DOI: 10.3389/fmicb.2019.01065] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 04/26/2019] [Indexed: 11/13/2022] Open
Abstract
Empirical evidence of the cost of producing toxic compounds in harmful microalgae is completely lacking. Yet costs are often assumed to be high, implying substantial ecological benefits with adaptive significance exist. To study potential fitness costs of toxin production, 16 strains including three species of the former Alexandrium tamarense species complex were grown under both carbon limitation and unlimited conditions. Growth rates, levels of intracellular paralytic shellfish toxins (PSTs), and effects of lytic compounds were measured to provide trade-off curves of toxicity for both PST and lytic toxicity under high light (300 μmol photons m-2 s-1) and under low light (i.e., carbon limited; 20 μmol photons m-2 s-1). Fitness costs in terms of reduced growth rates with increasing PST content were only evident under unlimited conditions, but not under carbon limitation, in which case PST production was positively correlated with growth. The cost of production of lytic compounds was detected both under carbon limitation and unlimited conditions, but only in strains producing PST. The results may direct future research in understanding the evolutionary role and ecological function of algal toxins. The intrinsic growth rate costs should be accounted for in relation to quantifying benefits such as grazer avoidance or toxin-mediated prey capture in natural food web settings.
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Affiliation(s)
- Hannah E Blossom
- Marine Biological Section, Department of Biology, University of Copenhagen, Elsinore, Denmark
| | - Bo Markussen
- Department of Mathematical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Niels Daugbjerg
- Marine Biological Section, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Bernd Krock
- Alfred-Wegener Institut für Polar-und Meeresforschung, Bremerhaven, Germany
| | - Andreas Norlin
- Marine Biological Section, Department of Biology, University of Copenhagen, Elsinore, Denmark
| | - Per Juel Hansen
- Marine Biological Section, Department of Biology, University of Copenhagen, Elsinore, Denmark
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19
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Griffin JE, Park G, Dam HG. Relative importance of nitrogen sources, algal alarm cues and grazer exposure to toxin production of the marine dinoflagellate Alexandrium catenella. HARMFUL ALGAE 2019; 84:181-187. [PMID: 31128802 DOI: 10.1016/j.hal.2019.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 03/27/2019] [Accepted: 04/09/2019] [Indexed: 06/09/2023]
Abstract
Dinoflagellate paralytic shellfish toxin (PST) production is mediated by several abiotic and biotic factors. This study compared the relative importance of nitrogen source and concentration, prey alarm cues and grazer presence on toxin production of the marine dinoflagellate Alexandrium catenella (Group I, strain BF-5). In separate assays run under either nutrient-replete (F/2 medium) or nutrient-depleted (filtered seawater) conditions, PST production of A. catenella was measured as a function of varying concentrations of added nitrogen sources (ammonium and urea), alarm cues from lysed conspecific (A. catenella Group I strains) and interspecific (the diatom, Thalassiosira weissflogii, and the green flagellate, Tetraselmis sp.) algae, and the presence of a grazer (the copepod Acartia hudsonica). Results showed that addition of ammonium or urea did not increase PST production. Unexpectedly, interspecific alarm cues increased toxin production but conspecific ones did not. Grazer presence dramatically induced PST production in A. catenella, irrespective of nutrient conditions, and this effect was an order of magnitude greater than any of the other variables tested. These results corroborate previous studies on grazer-induced PST production, and support the hypothesis that grazer-induced toxin production is not an experimental artifact, but rather a prey defense mechanism.
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Affiliation(s)
- Jessica E Griffin
- University of Connecticut, Department of Marine Sciences, 1080 Shennecossett Road, Groton, CT, 06340, USA.
| | - Gihong Park
- University of Connecticut, Department of Marine Sciences, 1080 Shennecossett Road, Groton, CT, 06340, USA.
| | - Hans G Dam
- University of Connecticut, Department of Marine Sciences, 1080 Shennecossett Road, Groton, CT, 06340, USA.
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20
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Cadier M, Andersen KH, Visser AW, Kiørboe T. Competition–defense tradeoff increases the diversity of microbial plankton communities and dampens trophic cascades. OIKOS 2019. [DOI: 10.1111/oik.06101] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Mathilde Cadier
- Centre for Ocean Life, DTU Aqua, Technical Univ. of Denmark 2800 Kgs. Lyngby Denmark
| | - Ken H. Andersen
- Centre for Ocean Life, DTU Aqua, Technical Univ. of Denmark 2800 Kgs. Lyngby Denmark
| | - Andre W. Visser
- Centre for Ocean Life, DTU Aqua, Technical Univ. of Denmark 2800 Kgs. Lyngby Denmark
| | - Thomas Kiørboe
- Centre for Ocean Life, DTU Aqua, Technical Univ. of Denmark 2800 Kgs. Lyngby Denmark
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