1
|
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.
Collapse
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
| |
Collapse
|
2
|
Deknock A, Pasmans F, van Leeuwenberg R, Van Praet S, De Troyer N, Goessens T, Lammens L, Bruneel S, Lens L, Martel A, Croubels S, Goethals P. Impact of heavy metal exposure on biological control of a deadly amphibian pathogen by zooplankton. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 823:153800. [PMID: 35150694 DOI: 10.1016/j.scitotenv.2022.153800] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 02/07/2022] [Accepted: 02/07/2022] [Indexed: 06/14/2023]
Abstract
Despite devastating effects on global biodiversity, efficient mitigation strategies against amphibian chytridiomycosis are lacking. Since the free-living pathogenic zoospores of Batrachochytrium dendrobatidis (Bd), the infective stage of this disease, can serve as a nutritious food source for components of zooplankton communities, these groups may act as biological control agents by eliminating zoospores from the aquatic environment. Such pathogen-predator interaction is, however, embedded in the aquatic food web structure and is therefore affected by abiotic factors interfering with these networks. Heavy metals, released from both natural and anthropogenic sources, are widespread contaminants of aquatic ecosystems and may interfere with planktonic communities and thus pathogen elimination rates. We investigated the interaction between zooplankton communities and chytridiomycosis infections in a Flemish agricultural region. Moreover, we also investigated the impact of heavy metal contamination, that was previously investigated in the region and presented in recent work, on zooplankton assemblages and chytridiomycosis infections. Finally, we tested the effect of sublethal concentrations of copper and zinc on Bd removal rates by Daphnia magna in a laboratory assay. Although zinc, copper, nickel and chromium were widely abundant pollutants, heavy metals were no driving force for zooplankton assemblages at our study locations. Moreover, our field survey did not reveal indirect effects of zooplankton assemblages on chytridiomycosis infections. However, sampling occasions testing negative for Bd showed a higher degree of copper contamination compared to positive sampling occasions, indicating a potential inhibitory effect of copper on Bd prevalence. Finally, whereas D. magna significantly reduced zoospore densities in its environment, sublethal concentrations of copper and zinc showed no interference with pathogen removal in the laboratory assay. Our results provide perspectives for further research on such a biological control strategy against chytridiomycosis by optimizing environmental conditions for pathogen predation.
Collapse
Affiliation(s)
- Arne Deknock
- Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Building F, B-9000 Ghent, Belgium.
| | - Frank Pasmans
- Department of Pathobiology, Pharmacology and Zoological Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, D9, B-9820 Merelbeke, Belgium
| | - Robby van Leeuwenberg
- Department of Pathobiology, Pharmacology and Zoological Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, D9, B-9820 Merelbeke, Belgium
| | - Sarah Van Praet
- Department of Pathobiology, Pharmacology and Zoological Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, D9, B-9820 Merelbeke, Belgium
| | - Niels De Troyer
- Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Building F, B-9000 Ghent, Belgium
| | - Tess Goessens
- Department of Pathobiology, Pharmacology and Zoological Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, D9, B-9820 Merelbeke, Belgium
| | - Leni Lammens
- Department of Pathobiology, Pharmacology and Zoological Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, D9, B-9820 Merelbeke, Belgium
| | - Stijn Bruneel
- Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Building F, B-9000 Ghent, Belgium
| | - Luc Lens
- Department of Biology, Faculty of Sciences, Ghent University, K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium
| | - An Martel
- Department of Pathobiology, Pharmacology and Zoological Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, D9, B-9820 Merelbeke, Belgium
| | - Siska Croubels
- Department of Pathobiology, Pharmacology and Zoological Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, D9, B-9820 Merelbeke, Belgium
| | - Peter Goethals
- Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Building F, B-9000 Ghent, Belgium
| |
Collapse
|
3
|
Sarkar P, Stefi Raju V, Kuppusamy G, Rahman MA, Elumalai P, Harikrishnan R, Arshad A, Arockiaraj J. Pathogenic fungi affecting fishes through their virulence molecules. AQUACULTURE 2022; 548:737553. [DOI: 10.1016/j.aquaculture.2021.737553] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2023]
|
4
|
De Troyer N, Bruneel S, Lock K, Greener MS, Facq E, Deknock A, Martel A, Pasmans F, Goethals P. Ratio-dependent functional response of two common Cladocera present in farmland ponds to Batrachochytrium dendrobatidis. FUNGAL ECOL 2021. [DOI: 10.1016/j.funeco.2021.101089] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
5
|
Deknock A, Pasmans F, van Leeuwenberg R, Van Praet S, Bruneel S, Lens L, Croubels S, Martel A, Goethals P. Alternative food sources interfere with removal of a fungal amphibian pathogen by zooplankton. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.14018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Arne Deknock
- Department of Animal Sciences and Aquatic Ecology Faculty of Bioscience Engineering Ghent University Ghent Belgium
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Poultry Diseases Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - Robby van Leeuwenberg
- Department of Pathology, Bacteriology and Poultry Diseases Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - Sarah Van Praet
- Department of Pathology, Bacteriology and Poultry Diseases Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - Stijn Bruneel
- Department of Animal Sciences and Aquatic Ecology Faculty of Bioscience Engineering Ghent University Ghent Belgium
| | - Luc Lens
- Department of Biology Faculty of Sciences Ghent University Ghent Belgium
| | - Siska Croubels
- Department of Pharmacology Toxicology and Biochemistry Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - An Martel
- Department of Pathology, Bacteriology and Poultry Diseases Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - Peter Goethals
- Department of Animal Sciences and Aquatic Ecology Faculty of Bioscience Engineering Ghent University Ghent Belgium
| |
Collapse
|
6
|
Farthing HN, Jiang J, Henwood AJ, Fenton A, Garner TWJ, Daversa DR, Fisher MC, Montagnes DJS. Microbial Grazers May Aid in Controlling Infections Caused by the Aquatic Zoosporic Fungus Batrachochytrium dendrobatidis. Front Microbiol 2021; 11:592286. [PMID: 33552011 PMCID: PMC7858660 DOI: 10.3389/fmicb.2020.592286] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 12/16/2020] [Indexed: 11/13/2022] Open
Abstract
Free-living eukaryotic microbes may reduce animal diseases. We evaluated the dynamics by which micrograzers (primarily protozoa) apply top-down control on the chytrid Batrachochytrium dendrobatidis (Bd) a devastating, panzootic pathogen of amphibians. Although micrograzers consumed zoospores (∼3 μm), the dispersal stage of chytrids, not all species grew monoxenically on zoospores. However, the ubiquitous ciliate Tetrahymena pyriformis, which likely co-occurs with Bd, grew at near its maximum rate (r = 1.7 d-1). A functional response (ingestion vs. prey abundance) for T. pyriformis, measured using spore-surrogates (microspheres) revealed maximum ingestion (I max ) of 1.63 × 103 zoospores d-1, with a half saturation constant (k) of 5.75 × 103 zoospores ml-1. Using these growth and grazing data we developed and assessed a population model that incorporated chytrid-host and micrograzer dynamics. Simulations using our data and realistic parameters obtained from the literature suggested that micrograzers could control Bd and potentially prevent chytridiomycosis (defined as 104 sporangia host-1). However, simulated inferior micrograzers (0.7 × I max and 1.5 × k) did not prevent chytridiomycosis, although they ultimately reduced pathogen abundance to below levels resulting in disease. These findings indicate how micrograzer responses can be applied when modeling disease dynamics for Bd and other zoosporic fungi.
Collapse
Affiliation(s)
- Hazel N. Farthing
- Shanghai Universities Key Laboratory of Marine Animal Taxonomy and Evolution, Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
- Department of Evolution, Ecology and Behaviour, Biosciences Building, University of Liverpool, Liverpool, United Kingdom
| | - Jiamei Jiang
- Shanghai Universities Key Laboratory of Marine Animal Taxonomy and Evolution, Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Alexandra J. Henwood
- Department of Evolution, Ecology and Behaviour, Biosciences Building, University of Liverpool, Liverpool, United Kingdom
| | - Andy Fenton
- Department of Evolution, Ecology and Behaviour, Biosciences Building, University of Liverpool, Liverpool, United Kingdom
| | - Trent W. J. Garner
- Institute of Zoology, Zoological Society of London, London, United Kingdom
| | - David R. Daversa
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, United Kingdom
| | - Matthew C. Fisher
- Department of Evolution, Ecology and Behaviour, Biosciences Building, University of Liverpool, Liverpool, United Kingdom
- Institute of Zoology, Zoological Society of London, London, United Kingdom
| | - David J. S. Montagnes
- Department of Evolution, Ecology and Behaviour, Biosciences Building, University of Liverpool, Liverpool, United Kingdom
| |
Collapse
|
7
|
Towards a food web based control strategy to mitigate an amphibian panzootic in agricultural landscapes. Glob Ecol Conserv 2020. [DOI: 10.1016/j.gecco.2020.e01314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
|
8
|
Frenken T, Miki T, Kagami M, Van de Waal DB, Van Donk E, Rohrlack T, Gsell AS. The potential of zooplankton in constraining chytrid epidemics in phytoplankton hosts. Ecology 2019; 101:e02900. [PMID: 31544240 PMCID: PMC7003484 DOI: 10.1002/ecy.2900] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 07/18/2019] [Accepted: 08/26/2019] [Indexed: 11/10/2022]
Abstract
Fungal diseases threaten natural and man‐made ecosystems. Chytridiomycota (chytrids) infect a wide host range, including phytoplankton species that form the basis of aquatic food webs and produce roughly half of Earth's oxygen. However, blooms of large or toxic phytoplankton form trophic bottlenecks, as they are inedible to zooplankton. Chytrids infecting inedible phytoplankton provide a trophic link to zooplankton by producing edible zoospores of high nutritional quality. By grazing chytrid zoospores, zooplankton may induce a trophic cascade, as a decreased zoospore density will reduce new infections. Conversely, fewer infections will not produce enough zoospores to sustain long‐term zooplankton growth and reproduction. This intricate balance between zoospore density necessary for zooplankton energetic demands (growth/survival), and the loss in new infections (and thus new zoospores) because of grazing was tested empirically. To this end, we exposed a cyanobacterial host (Planktothrix rubescens) infected by a chytrid (Rizophydium megarrhizum) to a grazer density gradient (the rotifer Keratella cf. cochlearis). Rotifers survived and reproduced on a zoospore diet, but the Keratella population growth was limited by the amount of zoospores provided by chytrid infections, resulting in a situation where zooplankton survived but were restricted in their ability to control disease in the cyanobacterial host. We subsequently developed and parameterized a dynamical food‐chain model using an allometric relationship for clearance rate to assess theoretically the potential of different‐sized zooplankton groups to restrict disease in phytoplankton hosts. Our model suggests that smaller‐sized zooplankton may have a high potential to reduce chytrid infections on inedible phytoplankton. Together, our results point out the complexity of three‐way interactions between hosts, parasites, and grazers and highlight that trophic cascades are not always sustainable and may depend on the grazer's energetic demand.
Collapse
Affiliation(s)
- Thijs Frenken
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, Wageningen, 6708 PB, The Netherlands.,Department of Ecosystem Research, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301, Berlin, 12587, Germany
| | - Takeshi Miki
- Department of Environmental Solution Technology, Faculty of Science and Technology, Ryukoku University, 1-5 Yokotani, Seta Oe-cho, Otsu, 520-2194, Japan.,Institute of Oceanography, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 107, Taiwan
| | - Maiko Kagami
- Graduate School of Environment and Information Sciences, Yokohama National University, 79-7, Tokiwadai, Hodogaya-ku, 240-8501, Japan
| | - Dedmer B Van de Waal
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, Wageningen, 6708 PB, The Netherlands
| | - Ellen Van Donk
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, Wageningen, 6708 PB, The Netherlands.,Institute of Environmental Biology, University of Utrecht, P.O. Box 80.056, Utrecht, 3508 TB, The Netherlands
| | - Thomas Rohrlack
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, Ås, NO-1432, Norway
| | - Alena S Gsell
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, Wageningen, 6708 PB, The Netherlands
| |
Collapse
|