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Salmaso N, Cerasino L, Pindo M, Boscaini A. Taxonomic and functional metagenomic assessment of a Dolichospermum bloom in a large and deep lake south of the Alps. FEMS Microbiol Ecol 2024; 100:fiae117. [PMID: 39227168 PMCID: PMC11412076 DOI: 10.1093/femsec/fiae117] [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: 04/03/2024] [Revised: 08/19/2024] [Accepted: 09/02/2024] [Indexed: 09/05/2024] Open
Abstract
Untargeted genetic approaches can be used to explore the high metabolic versatility of cyanobacteria. In this context, a comprehensive metagenomic shotgun analysis was performed on a population of Dolichospermum lemmermannii collected during a surface bloom in Lake Garda in the summer of 2020. Using a phylogenomic approach, the almost complete metagenome-assembled genome obtained from the analysis allowed to clarify the taxonomic position of the species within the genus Dolichospermum and contributed to frame the taxonomy of this genus within the ADA group (Anabaena/Dolichospermum/Aphanizomenon). In addition to common functional traits represented in the central metabolism of photosynthetic cyanobacteria, the genome annotation uncovered some distinctive and adaptive traits that helped define the factors that promote and maintain bloom-forming heterocytous nitrogen-fixing Nostocales in oligotrophic lakes. In addition, genetic clusters were identified that potentially encode several secondary metabolites that were previously unknown in the populations evolving in the southern Alpine Lake district. These included geosmin, anabaenopetins, and other bioactive compounds. The results expanded the knowledge of the distinctive competitive traits that drive algal blooms and provided guidance for more targeted analyses of cyanobacterial metabolites with implications for human health and water resource use.
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Affiliation(s)
- Nico Salmaso
- Research and Innovation Centre, Fondazione Edmund Mach, Via Edmund Mach, 1, 38098 San Michele all'Adige, Italy
- NBFC, National Biodiversity Future Center, Palermo 90133, Italy
| | - Leonardo Cerasino
- Research and Innovation Centre, Fondazione Edmund Mach, Via Edmund Mach, 1, 38098 San Michele all'Adige, Italy
| | - Massimo Pindo
- Research and Innovation Centre, Fondazione Edmund Mach, Via Edmund Mach, 1, 38098 San Michele all'Adige, Italy
| | - Adriano Boscaini
- Research and Innovation Centre, Fondazione Edmund Mach, Via Edmund Mach, 1, 38098 San Michele all'Adige, Italy
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2
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Junier P, Cailleau G, Fatton M, Udriet P, Hashmi I, Bregnard D, Corona-Ramirez A, Francesco ED, Kuhn T, Mangia N, Zhioua S, Hunkeler D, Bindschedler S, Sieber S, Gonzalez D. A cohesive Microcoleus strain cluster causes benthic cyanotoxic blooms in rivers worldwide. WATER RESEARCH X 2024; 24:100252. [PMID: 39308956 PMCID: PMC11416633 DOI: 10.1016/j.wroa.2024.100252] [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: 03/23/2024] [Revised: 08/21/2024] [Accepted: 08/27/2024] [Indexed: 09/25/2024]
Abstract
Over the last two decades, proliferations of benthic cyanobacteria producing derivatives of anatoxin-a have been reported in rivers worldwide. Here, we follow up on such a toxigenic event happening in the Areuse river in Switzerland and investigate the diversity and genomics of major bloom-forming riverine benthic cyanobacteria. We show, using 16S rRNA-based community profiling, that benthic communities are dominated by Oscillatoriales. We correlate the detection of one Microcoleus sequence variant matching the Microcoleus anatoxicus species with the presence of anatoxin-a derivatives and use long-read metagenomics to assemble complete circular genomes of the strain. The main dihydro-anatoxin-a-producing strain in the Areuse is distinct from strains isolated in New Zealand, the USA, and Canada, but forms a monophyletic strain cluster with them with average nucleotide identity values close to the species threshold. Compared to the rest of the Microcoleus genus, the toxin-producing strains encode a 15 % smaller genome, lacking genes for the synthesis of some essential vitamins. Toxigenic mats harbor a distinct microbiome dominated by proteobacteria and bacteroidetes, which may support cyanobacterial growth by providing them with essential nutrients. We recommend that strains closely related to M. anatoxicus be monitored internationally in order to help predict and mitigate similar cyanotoxic events.
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Affiliation(s)
- Pilar Junier
- Laboratory of Microbiology, University of Neuchâtel, Switzerland
| | | | - Mathilda Fatton
- Laboratory of Microbiology, University of Neuchâtel, Switzerland
| | - Pauline Udriet
- Laboratory of Microbiology, University of Neuchâtel, Switzerland
| | - Isha Hashmi
- Laboratory of Microbiology, University of Neuchâtel, Switzerland
| | - Danae Bregnard
- Laboratory of Microbiology, University of Neuchâtel, Switzerland
| | | | - Eva di Francesco
- Laboratory of Microbiology, University of Neuchâtel, Switzerland
| | - Thierry Kuhn
- Laboratory of Microbiology, University of Neuchâtel, Switzerland
| | - Naïma Mangia
- Laboratory of Microbiology, University of Neuchâtel, Switzerland
| | - Sami Zhioua
- Laboratory of Microbiology, University of Neuchâtel, Switzerland
| | - Daniel Hunkeler
- Centre for Hydrogeology and Geothermics, University of Neuchâtel, Switzerland
| | | | - Simon Sieber
- Department of Chemistry, University of Zürich, Switzerland
| | - Diego Gonzalez
- Laboratory of Microbiology, University of Neuchâtel, Switzerland
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3
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Chen Y, Jiang Y, He Z, Gao J, Li R, Yu G. First report of PST-producing Microseira wollei from China reveals its novel toxin profile. HARMFUL ALGAE 2024; 137:102655. [PMID: 39003021 DOI: 10.1016/j.hal.2024.102655] [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: 01/16/2024] [Revised: 04/26/2024] [Accepted: 05/21/2024] [Indexed: 07/15/2024]
Abstract
Microseira wollei, a globally distributed freshwater bloom-forming benthic cyanobacterium, is known for its production of cyanotoxins and taste and odor (T&O). While CYN (Cylindrospermopsin)-producing populations of M. wollei are confined to Australia, PST (Paralytic shellfish toxins)-producing populations have been exclusively documented in North America. In this study, four benthic cyanobacterial strains, isolated from West Lake in China, were identified as M. wollei based on morphological and phylogenetic analyses. Detection of sxtA gene and UPLC-MS/MS analysis conclusively confirmed the PST-producing capability of M. wollei CHAB5998. In the phylogenetic tree of 16S rDNA, M. wollei strains formed a monophyletic group with two subclades. Notably, non-PST-producing Chinese strains clustered with Australian strains in Clade II, while all other strains, including PST-producing ones, clustered in Clade I. Additionally, CHAB5998 contains ten PST variants, of which STX, NEO, GTX2, GTX3, GTX5 and C1 were identified for the first time in M. wollei. Sequence analysis of PST biosynthetic gene cluster (sxt) genes indicated potential base variations, gene rearrangements, insertions, and deletions in the strain CHAB5998. Also, sxt gene has a longer evolutionary history in M. wollei than that in cyanobacteria from Nostocales. Multiple recombination breakpoints detected in sxt genes and the inconsistency in the topology of the phylogenetic trees between sxt and 16S rDNA suggested that multiple horizontal gene transfers (HGT) have occurred. Overall, the present study marks the first documented occurrence of PST-producing M. wollei outside of North America and identifies it as the first toxic freshwater benthic cyanobacterium in China. This revelation implies that benthic cyanobacteria may pose a higher environmental risk in China than previously acknowledged.
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Affiliation(s)
- Youxin Chen
- CAS Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Yongguang Jiang
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Zhongshi He
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD, 21202, USA
| | - Jin Gao
- CAS Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Renhui Li
- Zhejiang Provincial Key Laboratory for Subtropical Water Environment and Marine Biological Resources Protection, Wenzhou University, Wenzhou, 325035, China; National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou, Zhejiang, 325035, China
| | - Gongliang Yu
- CAS Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
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Jablonska M, Cerasino L, Boscaini A, Capelli C, Greco C, Krivograd Klemenčič A, Mischke U, Salmaso N, Kurmayer R. Distribution of toxigenic cyanobacteria in Alpine lakes and rivers as revealed by molecular screening. WATER RESEARCH 2024; 258:121783. [PMID: 38805870 DOI: 10.1016/j.watres.2024.121783] [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: 03/01/2024] [Revised: 05/09/2024] [Accepted: 05/13/2024] [Indexed: 05/30/2024]
Abstract
The increasing frequency of cyanobacteria blooms in waterbodies caused by ecosystem eutrophication could endanger human health. This risk can be mitigated by effective monitoring incorporating molecular methods. To date, most molecular studies on toxigenic cyanobacteria have been limited to microcystins (MCs), disregarding other cyanotoxins, to freshwater planktic habitats while ignoring benthic habitats, and to limited geographic areas (usually one or a few specific waterbodies). In this study, we used PCR-based methods including PCR product sequencing and chemical-analytical methods (LC-MS/MS) to screen many plankton (n = 123) and biofilm samples (n = 113) originating from 29 Alpine lakes and 18 rivers for their cyanotoxin production potential. Both mcyE (indicating MC synthesis) and anaC (indicating anatoxin (ATX) synthesis) gene fragments were able to qualitatively predict MC or ATX occurrence. The abundance of mcyE gene fragments was significantly related to MC concentrations in plankton samples (R2 = 0.61). mcyE gene fragments indicative of MC synthesis were most abundant in planktic samples (65 %) and were assigned to the genera Planktothrix and Microcystis. However, mcyE rarely occurred in biofilms of lakes and rivers, i.e., 4 % and 5 %, respectively, and were assigned to Microcystis, Planktothrix, and Nostoc. In contrast, anaC gene fragments occurred frequently in planktic samples (14 % assigned to Tychonema, Phormidium (Microcoleus), and Oscillatoria), but also in biofilms of lakes (49 %) and rivers (18 %) and were assigned to the genera Phormidium, Oscillatoria, and Nostocales. The cyrJ gene fragment indicating cylindrospermopsin synthesis occurred only once in plankton (assigned to Dolichospermum), while saxitoxin synthesis potential was not detected. For plankton samples, monomictic and less eutrophic conditions were positively related to mcyE/MC occurrence frequency, while oligomictic conditions were related to anaC/ATX frequency. The anaC/ATX frequency in biofilm was related to the lake habitats generally showing higher biodiversity as revealed from metabarcoding in a parallel study.
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Affiliation(s)
- Maša Jablonska
- National Institute of Biology, Večna pot 121, 1000 Ljubljana, Slovenia; University of Ljubljana, Slovenia; Research Department for Limnology, Universität Innsbruck, Mondseestrasse 9, 5310 Mondsee, Austria.
| | - Leonardo Cerasino
- Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Italy
| | - Adriano Boscaini
- Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Italy
| | - Camilla Capelli
- Institute of Earth Sciences, University of Applied Sciences and Arts of Southern Switzerland (SUPSI), Mendrisio, Switzerland
| | - Claudia Greco
- Italian Institute for Environmental Protection and Research (ISPRA), Ozzano dell'Emilia, Bologna, Italy
| | | | - Ute Mischke
- Bavarian Environment Agency, Ref. 83, Wielenbach, Germany
| | - Nico Salmaso
- Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Italy; NBFC, National Biodiversity Future Center, Palermo, Italy
| | - Rainer Kurmayer
- Research Department for Limnology, Universität Innsbruck, Mondseestrasse 9, 5310 Mondsee, Austria; Universität Innsbruck, Innrain 52, 6020 Innsbruck, Austria.
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5
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Guden RM, Haegeman A, Ruttink T, Moens T, Derycke S. Nematodes alter the taxonomic and functional profiles of benthic bacterial communities: A metatranscriptomic approach. Mol Ecol 2024; 33:e17331. [PMID: 38533629 DOI: 10.1111/mec.17331] [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: 06/21/2023] [Revised: 02/25/2024] [Accepted: 03/18/2024] [Indexed: 03/28/2024]
Abstract
Marine sediments cover 70% of the Earth's surface, and harbour diverse bacterial communities critical for marine biogeochemical processes, which affect climate change, biodiversity and ecosystem functioning. Nematodes, the most abundant and species-rich metazoan organisms in marine sediments, in turn, affect benthic bacterial communities and bacterial-mediated ecological processes, but the underlying mechanisms by which they affect biogeochemical cycles remain poorly understood. Here, we demonstrate using a metatranscriptomic approach that nematodes alter the taxonomic and functional profiles of benthic bacterial communities. We found particularly strong stimulation of nitrogen-fixing and methane-oxidizing bacteria in the presence of nematodes, as well as increased functional activity associated with methane metabolism and degradation of various carbon compounds. This study provides empirical evidence that the presence of nematodes results in taxonomic and functional shifts in active bacterial communities, indicating that nematodes may play an important role in benthic ecosystem processes.
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Affiliation(s)
- Rodgee Mae Guden
- Marine Biology Unit, Department of Biology, Ghent University, Ghent, Belgium
| | - Annelies Haegeman
- Plant Sciences Unit, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Melle, Belgium
| | - Tom Ruttink
- Plant Sciences Unit, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Melle, Belgium
| | - Tom Moens
- Marine Biology Unit, Department of Biology, Ghent University, Ghent, Belgium
| | - Sofie Derycke
- Marine Biology Unit, Department of Biology, Ghent University, Ghent, Belgium
- Aquatic Environment and Quality, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Oostende, Belgium
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Purker M, Dobrovolny S, Kreuml M, Hufnagl P, Indra A, Kurmayer R. Quantitative relationships among high-throughput sequencing, cyanobacteria toxigenic genotype abundance and microcystin occurrence in bathing waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 901:165934. [PMID: 37543325 DOI: 10.1016/j.scitotenv.2023.165934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 07/29/2023] [Accepted: 07/29/2023] [Indexed: 08/07/2023]
Abstract
Toxin-producing cyanobacteria pose significant threats to human and animal health if exposed during recreational activities in bathing waters. To better safeguard public health and reduce health risks during the bathing season, an effective monitoring and management strategy is required. Molecular tools used to monitor toxigenic cyanobacteria have been evaluated on the basis of the efficiency and applicability of the method used to (i) establish an early-warning monitoring strategy for EU bathing water sites using both targeted quantitative polymerase chain reaction (qPCR) and non-targeted high-throughput sequencing (HTS) genotype analysis and (ii) to compare the toxigenic potential of cyanobacteria with actual microcystin (MC) occurrence and concentrations. For this purpose, 16 bathing water sites were monitored according to the bathing water directive (BWD) of the European Union (EU) during the bathing season of the summer of 2020 in eastern Austria. The cyanobacterial community composition was analyzed through HTS and qPCR by targeting the microcystin synthetase B gene (mcyB), which indicates MC synthesis within the genera Microcystis and Planktothrix. Within the genus Microcystis, which was identified as the primary MC producer, the mcyB genotypes formed stable subpopulations that increased linearly in correlation with the total Microcystis population. Notably, the HTS cell equivalents assigned to Microcystis and Planktothrix correlated with the corresponding qPCR estimates of genotype abundance, which serves as a confirmation of the suitability of (semi)-quantitative sequencing through HTS. In addition to the elevated trophic state, reduced transparency, increasing water temperatures, as well as cyanobacterial HTS read numbers and Microcystis cell number equivalents per mL estimated through qPCR, were associated with positive MC samples. Therefore, in combination with the monitoring of standard environmental parameters, the use of HTS and qPCR techniques is considered highly useful to ensure the timely identification of health risks to recreational users, as mandated by the BWD.
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Affiliation(s)
- Magdalena Purker
- Austrian Agency for Health and Food Safety, Institute for Medical Microbiology and Hygiene - Center for Anthropogenic Infections, Department of Clinical Molecular Biology, Währinger Straße 25a, 1090 Vienna, Austria; Austrian Agency for Health and Food Safety, Institute for Medical Microbiology and Hygiene - Center for Anthropogenic Infections, Department of Water and Hygiene, Währinger Straße 25a, 1090 Vienna, Austria; Universität Innsbruck, Research Department for Limnology, Mondseestrasse 9, 5310 Mondsee, Austria and Universität Innsbruck, Innrain 52, 6020 Innsbruck.
| | - Stefanie Dobrovolny
- Austrian Agency for Health and Food Safety, Institute for Food Safety, Department of Molecular Biology and Microbiology, Spargelfeldstraße 191, 1220 Vienna, Austria
| | - Michaela Kreuml
- Austrian Agency for Health and Food Safety, Institute for Hydroanalytics, Wieningerstraße 8, 4020 Linz, Austria
| | - Peter Hufnagl
- Austrian Agency for Health and Food Safety, Institute for Medical Microbiology and Hygiene - Center for Anthropogenic Infections, Department of Clinical Molecular Biology, Währinger Straße 25a, 1090 Vienna, Austria
| | - Alexander Indra
- Austrian Agency for Health and Food Safety, Institute for Medical Microbiology and Hygiene, Währinger Straße 25a, 1090 Vienna, Austria
| | - Rainer Kurmayer
- Universität Innsbruck, Research Department for Limnology, Mondseestrasse 9, 5310 Mondsee, Austria and Universität Innsbruck, Innrain 52, 6020 Innsbruck
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Salmaso N, Boscaini A, Cerasino L, Pindo M, Pinto F, Segata N, Donati C. Draft genome sequence of the anatoxin-a producing cyanobacterium Tychonema bourrellyi B0820 isolated from the epilimnion of the deep Alpine Lake Garda. Microbiol Resour Announc 2023; 12:e0084423. [PMID: 37855624 PMCID: PMC10652907 DOI: 10.1128/mra.00844-23] [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: 09/07/2023] [Accepted: 09/18/2023] [Indexed: 10/20/2023] Open
Abstract
We report the draft genome sequence of strain B0820 of the cyanobacterium Tychonema bourrellyi isolated from the epilimnion of Lake Garda and assembled from a metagenome of a non-axenic culture. The strain analyzed was shown to produce anatoxin-a, a potent neurotoxin that can cause fatal intoxication in exposed organisms.
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Affiliation(s)
- Nico Salmaso
- Research and Innovation Centre, Fondazione Edmund Mach , San Michele all'Adige, Italy
- NBFC, National Biodiversity Future Center , Palermo, Italy
| | - Adriano Boscaini
- Research and Innovation Centre, Fondazione Edmund Mach , San Michele all'Adige, Italy
| | - Leonardo Cerasino
- Research and Innovation Centre, Fondazione Edmund Mach , San Michele all'Adige, Italy
| | - Massimo Pindo
- Research and Innovation Centre, Fondazione Edmund Mach , San Michele all'Adige, Italy
| | - Federica Pinto
- Department of Cellular, Computational and Integrative Biology, University of Trento , Trento, Italy
| | - Nicola Segata
- Department of Cellular, Computational and Integrative Biology, University of Trento , Trento, Italy
| | - Claudio Donati
- Research and Innovation Centre, Fondazione Edmund Mach , San Michele all'Adige, Italy
- NBFC, National Biodiversity Future Center , Palermo, Italy
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Stoyneva-Gärtner M, Stefanova K, Uzunov B, Radkova M, Gärtner G. Cuspidothrix Is the First Genetically Proved Anatoxin A Producer in Bulgarian Lakes and Reservoirs. Toxins (Basel) 2022; 14:toxins14110778. [PMID: 36356028 PMCID: PMC9696308 DOI: 10.3390/toxins14110778] [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: 10/14/2022] [Revised: 11/01/2022] [Accepted: 11/08/2022] [Indexed: 11/12/2022] Open
Abstract
The paper presents the first proof of planktonic cyanoprokaryote genus Cuspidothrix as an anatoxin A (ATX) producer in Bulgarian wetlands. The results from polymerase chain reaction (PCR) obtained from two summer sampling campaigns in 26 selected lakes and reservoirs demonstrated presence of the anaC gene, responsible for ATX production in 21 strains of the genus. They were found in three waterbodies sampled in 2018 (coastal lake Vaya, coastal reservoir Poroy, inland reservoir Sinyata Reka) and in four waterbodies sampled in 2019 (inland reservoirs Duvanli, Koprinka, Plachidol 2, Sinyata Reka). The detected genetic diversity generally corresponds to the observations conducted by conventional light microscopy, by which we distinguished three species of Cuspidothrix (Cuspidothrix issatschenkoi, Cuspidothrix elenkinii and Cuspidothrix tropicalis, the latter considered alien in the country). Eleven strains showed high similarity to two sequences of C. issatschenkoi available from the National Centre for Biotechnology Information (NCBI). Ten other strains assembled in a group, which-in lack of available from NCBI genetic sequences-were presumed related to C. tropicalis and C. elenkinii after comparison with the results from light microscopy. Cuspidothrix strains found in Bulgarian waterbodies showed high genetic similarity to those isolated and sequenced from Asia (Japan, China) and Northern Europe (Norway, Finland).
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Affiliation(s)
| | - Katerina Stefanova
- AgroBio Institute, Bulgarian Agricultural Academy, BG-1164 Sofia, Bulgaria
| | - Blagoy Uzunov
- Faculty of Biology, Department of Botany, Sofia University, BG-1164 Sofia, Bulgaria
- Correspondence:
| | - Mariana Radkova
- AgroBio Institute, Bulgarian Agricultural Academy, BG-1164 Sofia, Bulgaria
| | - Georg Gärtner
- Institute of Botany, Innsbruck University, A-6020 Innsbruck, Austria
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Schwarzenberger A. Negative Effects of Cyanotoxins and Adaptative Responses of Daphnia. Toxins (Basel) 2022; 14:770. [PMID: 36356020 PMCID: PMC9694520 DOI: 10.3390/toxins14110770] [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: 10/04/2022] [Revised: 11/02/2022] [Accepted: 11/05/2022] [Indexed: 11/10/2022] Open
Abstract
The plethora of cyanobacterial toxins are an enormous threat to whole ecosystems and humans. Due to eutrophication and increases in lake temperatures from global warming, changes in the distribution of cyanobacterial toxins and selection of few highly toxic species/ strains are likely. Globally, one of the most important grazers that controls cyanobacterial blooms is Daphnia, a freshwater model organism in ecology and (eco)toxicology. Daphnia-cyanobacteria interactions have been studied extensively, often focusing on the interference of filamentous cyanobacteria with Daphnia's filtering apparatus, or on different nutritional constraints (the lack of essential amino acids or lipids) and grazer toxicity. For a long time, this toxicity only referred to microcystins. Currently, the focus shifts toward other deleterious cyanotoxins. Still, less than 10% of the total scientific output deals with cyanotoxins that are not microcystins; although these other cyanotoxins can occur just as frequently and at similar concentrations as microcystins in surface water. This review discusses the effects of different cyanobacterial toxins (hepatotoxins, digestive inhibitors, neurotoxins, and cytotoxins) on Daphnia and provides an elaborate and up-to-date overview of specific responses and adaptations of Daphnia. Furthermore, scenarios of what we can expect for the future of Daphnia-cyanobacteria interactions are described by comprising anthropogenic threats that might further increase toxin stress in Daphnia.
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Affiliation(s)
- Anke Schwarzenberger
- Limnological Institute, University Konstanz, Mainaustr. 252, 78464 Konstanz, Germany
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10
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Spatio-Temporal Monitoring of Benthic Anatoxin-a-Producing Tychonema sp. in the River Lech, Germany. Toxins (Basel) 2022; 14:toxins14050357. [PMID: 35622603 PMCID: PMC9144322 DOI: 10.3390/toxins14050357] [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: 05/03/2022] [Revised: 05/16/2022] [Accepted: 05/19/2022] [Indexed: 11/16/2022] Open
Abstract
Incidents with toxic benthic cyanobacteria blooms have been increasing recently. In 2019, several dogs were poisoned in the river Lech (Germany) by the benthic anatoxin-a-producing genus Tychonema. To characterize spatial and temporal distribution of potentially toxic Tychonema in this river, a systematic monitoring was carried out in 2020, focusing on the occurrence of the genus, its toxin production and habitat requirements. Tychonema and cyanobacterial community composition in benthic mats and pelagic samples were identified using a combined approach of microscopy and DNA sequencing of the 16S rRNA gene. In addition, anatoxin-a concentrations of selected samples were measured using the ELISA method. The habitat was characterized to assess the ecological requirements and growth conditions of Tychonema. Tychonema mats and anatoxin-a were detected at several sampling sites throughout the entire study period. Toxin concentrations increased with the progression of the vegetation period and with flow direction, reaching values between 0 and 220.5 µg/L. Community composition differed among pelagic and benthic samples, with life zone and substrate condition being the most important factors. The results of this study highlight the importance of monitoring and understanding the factors determining occurrence and toxin production of both pelagic and benthic cyanobacteria due to their relevance for the health of humans and aquatic ecosystems.
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Sundaravadivelu D, Sanan TT, Venkatapathy R, Mash H, Tettenhorst D, DAnglada L, Frey S, Tatters AO, Lazorchak J. Determination of Cyanotoxins and Prymnesins in Water, Fish Tissue, and Other Matrices: A Review. Toxins (Basel) 2022; 14:toxins14030213. [PMID: 35324710 PMCID: PMC8949488 DOI: 10.3390/toxins14030213] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/10/2022] [Accepted: 03/13/2022] [Indexed: 12/10/2022] Open
Abstract
Harmful algal blooms (HABs) and their toxins are a significant and continuing threat to aquatic life in freshwater, estuarine, and coastal water ecosystems. Scientific understanding of the impacts of HABs on aquatic ecosystems has been hampered, in part, by limitations in the methodologies to measure cyanotoxins in complex matrices. This literature review discusses the methodologies currently used to measure the most commonly found freshwater cyanotoxins and prymnesins in various matrices and to assess their advantages and limitations. Identifying and quantifying cyanotoxins in surface waters, fish tissue, organs, and other matrices are crucial for risk assessment and for ensuring quality of food and water for consumption and recreational uses. This paper also summarizes currently available tissue extraction, preparation, and detection methods mentioned in previous studies that have quantified toxins in complex matrices. The structural diversity and complexity of many cyanobacterial and algal metabolites further impede accurate quantitation and structural confirmation for various cyanotoxins. Liquid chromatography–triple quadrupole mass spectrometer (LC–MS/MS) to enhance the sensitivity and selectivity of toxin analysis has become an essential tool for cyanotoxin detection and can potentially be used for the concurrent analysis of multiple toxins.
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Affiliation(s)
| | - Toby T. Sanan
- Office of Research and Development, Center for Environmental Solutions and Emergency Response, U.S. EPA, Cincinnati, OH 45268, USA; (H.M.); (D.T.)
- Correspondence: (T.T.S.); (J.L.); Tel.: +1-513-569-7076 (J.L.)
| | | | - Heath Mash
- Office of Research and Development, Center for Environmental Solutions and Emergency Response, U.S. EPA, Cincinnati, OH 45268, USA; (H.M.); (D.T.)
| | - Dan Tettenhorst
- Office of Research and Development, Center for Environmental Solutions and Emergency Response, U.S. EPA, Cincinnati, OH 45268, USA; (H.M.); (D.T.)
| | - Lesley DAnglada
- Office of Water, Science and Technology, U.S. EPA, Washington, DC 20004, USA; (L.D.); (S.F.)
| | - Sharon Frey
- Office of Water, Science and Technology, U.S. EPA, Washington, DC 20004, USA; (L.D.); (S.F.)
| | - Avery O. Tatters
- Center for Environmental Measurement and Modeling, U.S. EPA, Gulf Breeze, FL 32561, USA;
| | - James Lazorchak
- Center for Environmental Measurement and Modeling, U.S. EPA, Cincinnati, OH 45268, USA
- Correspondence: (T.T.S.); (J.L.); Tel.: +1-513-569-7076 (J.L.)
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Ahari H, Nowruzi B, Anvar AA, Porzani SJ. The Toxicity Testing of Cyanobacterial Toxins In Vivo and In Vitro by Mouse Bioassay: A Review. Mini Rev Med Chem 2021; 22:1131-1151. [PMID: 34720080 DOI: 10.2174/1389557521666211101162030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 07/26/2021] [Accepted: 08/21/2021] [Indexed: 11/22/2022]
Abstract
Different biological methods based on bioactivity are available to detect cyanotoxins, including neurotoxicity, immunological interactions, hepatotoxicity, cytotoxicity, and enzymatic activity. The mouse bioassay is the first test employed in laboratory cultures, cell extracts, and water bloom materials to detect toxins. It is also used as a traditional method to estimate the LD50. Concerning the ease of access and low cost, it is the most common method for this purpose. In this method, a sample is injected intraperitoneally into adult mice, and accordingly, they are assayed and monitored for about 24 hours for toxic symptoms. The toxin can be detected using this method from minutes to a few hours; its type, e.g., hepatotoxin, neurotoxin, etc., can also be determined. However, this method is nonspecific, fails to detect low amounts, and cannot distinguish between homologues. Although the mouse bioassay is gradually replaced with new chemical and immunological methods, it is still the main technique to detect the bioactivity and efficacy of cyanotoxins using LD50 determined based on the survival time of animals exposed to the toxin. In addition, some countries oppose animal use in toxicity studies. However, high cost, ethical considerations, low-sensitivity, non-specificity, and prolonged processes persuade researchers to employ chemical and functional analysis techniques. The qualitative and quantitative analyses, as well as high specificity and sensitivity, are among the advantages of cytotoxicity tests to investigate cyanotoxins. The present study aimed at reviewing the results obtained from in-vitro and in-vivo investigations of the mouse bioassay to detect cyanotoxins, including microcystins, cylindrospermopsin, saxitoxins, etc.
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Affiliation(s)
- Hamed Ahari
- Department of Food Science and Technology, Science and Research Branch, Islamic Azad University, Tehran. Iran
| | - Bahareh Nowruzi
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran. Iran
| | - Amir Ali Anvar
- Department of Food Hygiene, Science and Research Branch, Islamic Azad University, Tehran. Iran
| | - Samaneh Jafari Porzani
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran. Iran
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13
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Schwarzenberger A, Martin-Creuzburg D. Daphnia's Adaptive Molecular Responses to the Cyanobacterial Neurotoxin Anatoxin-α Are Maternally Transferred. Toxins (Basel) 2021; 13:toxins13050326. [PMID: 33946510 PMCID: PMC8147185 DOI: 10.3390/toxins13050326] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/27/2021] [Accepted: 04/29/2021] [Indexed: 11/16/2022] Open
Abstract
Cyanobacterial blooms are an omnipresent and well-known result of eutrophication and climate change in aquatic systems. Cyanobacteria produce a plethora of toxic secondary metabolites that affect humans, animals and ecosystems. Many cyanotoxins primarily affect the grazers of phytoplankton, e.g., Daphnia. The neurotoxin anatoxin-α has been reported world-wide; despite its potency, anatoxin-α and its effects on Daphnia have not been thoroughly investigated. Here, we investigated the effects of the anatoxin-α-producing Tychonema on life-history parameters and gene expression of nicotine-acetylcholine receptors (NAR), the direct targets of anatoxin-α, using several D. magna clones. We used juvenile somatic growth rates as a measure of fitness and analyzed gene expression by qPCR. Exposure to 100% Tychonema reduced the clones' growth rates and caused an up-regulation of NAR gene expression. When 50% of the food consisted of Tychonema, none of the clones were reduced in growth and only one of them showed an increase in NAR gene expression. We demonstrate that this increased NAR gene expression can be maternally transferred and that offspring from experienced mothers show a higher growth rate when treated with 50% Tychonema compared with control offspring. However, the addition of further (anthropogenic) stressors might impair Daphnia's adaptive responses to anatoxin-α. Especially the presence of certain pollutants (i.e., neonicotinoids), which also target NARs, might reduce Daphnia's capability to cope with anatoxin-α.
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14
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Wang Y, Fan H, Keung Wong P, Wu Y, Rittmann B. Biodegradation of tetracycline using hybrid material (UCPs-TiO 2) coupled with biofilms under visible light. BIORESOURCE TECHNOLOGY 2021; 323:124638. [PMID: 33418351 DOI: 10.1016/j.biortech.2020.124638] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/25/2020] [Accepted: 12/26/2020] [Indexed: 06/12/2023]
Abstract
To develop a more green and effective method for tetracycline (TC) removal, a hybrid material (conversion phosphors-TiO2, UCPs-TiO2) was coupled with a biofilm to achieve enhanced removal of TC. The removal of TC by biofilm coupled with UCPs-TiO2 under visible light reached 82%, which was 35% higher than that in treatment using only the biofilm. Extracellular polymeric substance (EPS) promoted the production of hydroxyl radicals by UCPs-TiO2, as the EPS acted as an electron transfer medium and accelerated the TC mineralization. Biofilm in the coupled system tolerated TC stress by regulating its antibiotic resistance genes (ARG) and superoxidedismutase (SOD), and allowed it to maintain stable and efficient removal of TC. This study documents a method to couple a hybrid material with microbial aggregates, creating a promising system for removing refractory organics, such as TC, from water. The study also offers insight into the mechanisms underlying TC removal by microbial aggregates combined with new functional materials.
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Affiliation(s)
- Yu Wang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China; Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, School of Environmental & Chemical Engineering, Nanchang University, Nanchang 330031, China
| | - Hua Fan
- Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, School of Environmental & Chemical Engineering, Nanchang University, Nanchang 330031, China
| | - Po Keung Wong
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong Special Administrative Region
| | - Yonghong Wu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China.
| | - Bruce Rittmann
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, AZ 85287-5701, USA
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15
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Colas S, Marie B, Lance E, Quiblier C, Tricoire-Leignel H, Mattei C. Anatoxin-a: Overview on a harmful cyanobacterial neurotoxin from the environmental scale to the molecular target. ENVIRONMENTAL RESEARCH 2021; 193:110590. [PMID: 33307089 DOI: 10.1016/j.envres.2020.110590] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 11/06/2020] [Accepted: 12/02/2020] [Indexed: 06/12/2023]
Abstract
Anatoxin-a (ATX-a) is a neurotoxic alkaloid, produced by several freshwater planktonic and benthic cyanobacteria (CB). Such CB have posed human and animal health issues for several years, as this toxin is able to cause neurologic symptoms in humans following food poisoning and death in wild and domestic animals. Different episodes of animal intoxication have incriminated ATX-a worldwide, as confirmed by the presence of ATX-a-producing CB in the consumed water or biofilm, or the observation of neurotoxic symptoms, which match experimental toxicity in vivo. Regarding toxicity parameters, toxicokinetics knowledge is currently incomplete and needs to be improved. The toxin can passively cross biological membranes and act rapidly on nicotinic receptors, its main molecular target. In vivo and in vitro acute effects of ATX-a have been studied and make possible to draw its mode of action, highlighting its deleterious effects on the nervous systems and its effectors, namely muscles, heart and vessels, and the respiratory apparatus. However, very little is known about its putative chronic toxicity. This review updates available data on ATX-a, from the ecodynamic of the toxin to its physiological and molecular targets.
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Affiliation(s)
- Simon Colas
- UMR 7245 CNRS/MNHN "Molécules de Communication et Adaptations des Micro-organismes", Muséum National d'Histoire Naturelle, Paris, France; Mitochondrial and Cardiovascular Pathophysiology - MITOVASC, UMR CNRS 6015, INSERM U1083, UBL/Angers University, Angers, France
| | - Benjamin Marie
- UMR 7245 CNRS/MNHN "Molécules de Communication et Adaptations des Micro-organismes", Muséum National d'Histoire Naturelle, Paris, France
| | - Emilie Lance
- UMR 7245 CNRS/MNHN "Molécules de Communication et Adaptations des Micro-organismes", Muséum National d'Histoire Naturelle, Paris, France
| | - Catherine Quiblier
- UMR 7245 CNRS/MNHN "Molécules de Communication et Adaptations des Micro-organismes", Muséum National d'Histoire Naturelle, Paris, France; Université de Paris - Paris Diderot, 5 rue Thomas Mann, Paris, France
| | - Hélène Tricoire-Leignel
- Mitochondrial and Cardiovascular Pathophysiology - MITOVASC, UMR CNRS 6015, INSERM U1083, UBL/Angers University, Angers, France.
| | - César Mattei
- Mitochondrial and Cardiovascular Pathophysiology - MITOVASC, UMR CNRS 6015, INSERM U1083, UBL/Angers University, Angers, France.
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16
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Plaas HE, Paerl HW. Toxic Cyanobacteria: A Growing Threat to Water and Air Quality. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:44-64. [PMID: 33334098 DOI: 10.1021/acs.est.0c06653] [Citation(s) in RCA: 103] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The global expansion of harmful cyanobacterial blooms (CyanoHABs) poses an increasing threat to public health. CyanoHABs are characterized by the production of toxic metabolites known as cyanotoxins. Human exposure to cyanotoxins is challenging to forecast, and perhaps the least understood exposure route is via inhalation. While the aerosolization of toxins from marine harmful algal blooms (HABs) has been well documented, the aerosolization of cyanotoxins in freshwater systems remains understudied. In recent years, spray aerosol (SA) produced in the airshed of the Laurentian Great Lakes (United States and Canada) has been characterized, suggesting that freshwater systems may impact atmospheric aerosol loading more than previously understood. Therefore, further investigation regarding the impact of CyanoHABs on human respiratory health is warranted. This review examines current research on the incorporation of cyanobacterial cells and cyanotoxins into SA of aquatic ecosystems which experience HABs. We present an overview of cyanotoxin fate in the environment, biological incorporation into SA, existing data on cyanotoxins in SA, relevant collection methods, and adverse health outcomes associated with cyanotoxin inhalation.
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Affiliation(s)
- Haley E Plaas
- University of North Carolina at Chapel Hill, Gillings School of Global Public Health, Chapel Hill, NC 27599, United States
- University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC 28557, United States
| | - Hans W Paerl
- University of North Carolina at Chapel Hill, Gillings School of Global Public Health, Chapel Hill, NC 27599, United States
- University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC 28557, United States
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17
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Mass Occurrence of Anatoxin-a- and Dihydroanatoxin-a-Producing Tychonema sp. in Mesotrophic Reservoir Mandichosee (River Lech, Germany) as a Cause of Neurotoxicosis in Dogs. Toxins (Basel) 2020; 12:toxins12110726. [PMID: 33233760 PMCID: PMC7699839 DOI: 10.3390/toxins12110726] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/17/2020] [Accepted: 11/17/2020] [Indexed: 12/25/2022] Open
Abstract
In August 2019, three dogs died after bathing in or drinking from Mandichosee, a mesotrophic reservoir of the River Lech (Germany). The dogs showed symptoms of neurotoxic poisoning and intoxication with cyanotoxins was considered. Surface blooms were not visible at the time of the incidents. Benthic Tychonema sp., a potential anatoxin-a (ATX)-producing cyanobacterium, was detected in mats growing on the banks, as biofilm on macrophytes and later as aggregations floating on the lake surface. The dogs' pathological examinations showed lung and liver lesions. ATX and dihydroanatoxin-a (dhATX) were detected by LC-MS/MS in the stomachs of two dogs and reached concentrations of 563 and 1207 µg/L, respectively. Anatoxins (sum of ATX and dhATX, ATXs) concentrations in field samples from Mandichosee ranged from 0.1 µg/L in the open water to 68,000 µg/L in samples containing a large amount of mat material. Other (neuro)toxic substances were not found. A molecular approach was used to detect toxin genes by PCR and to reveal the cyanobacterial community composition by sequencing. Upstream of Mandichosee, random samples were taken from other Lech reservoirs, uncovering Tychonema and ATXs at several sampling sites. Similar recent findings emphasize the importance of focusing on the investigation of benthic toxic cyanobacteria and applying appropriate monitoring strategies in the future.
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18
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Understanding the Differences in the Growth and Toxin Production of Anatoxin-Producing Cuspidothrix issatschenkoi Cultured with Inorganic and Organic N Sources from a New Perspective: Carbon/Nitrogen Metabolic Balance. Toxins (Basel) 2020; 12:toxins12110724. [PMID: 33228063 PMCID: PMC7699347 DOI: 10.3390/toxins12110724] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/14/2020] [Accepted: 11/17/2020] [Indexed: 11/22/2022] Open
Abstract
Cyanotoxins are the underlying cause of the threat that globally pervasive Cyanobacteria Harmful algal blooms (CyanoHABs) pose to humans. Major attention has been focused on the cyanobacterial hepatotoxin microcystins (MCs); however, there is a dearth of studies on cyanobacterial neurotoxin anatoxins. In this study, we explored how an anatoxin-producing Cuspidothrix issatschenkoi strain responded to culture with inorganic and organic nitrogen sources in terms of growth and anatoxins production. The results of our study revealed that ʟ- alanine could greatly boost cell growth, and was associated with the highest cell productivity, while urea significantly stimulated anatoxin production with the maximum anatoxin yield reaching 25.86 μg/mg dry weight, which was 1.56-fold higher than that in the control group (BG11). To further understand whether the carbon/nitrogen balance in C. issatschenkoi would affect anatoxin production, we explored growth and toxin production in response to different carbon/nitrogen ratios (C/N). Anatoxin production was mildly promoted when the C/N ratio was within low range, and significantly inhibited when the C/N ratio was within high range, showing approximately a three-fold difference. Furthermore, the transcriptional profile revealed that anaC gene expression was significantly up-regulated over 2–24 h when the C/N ratio was increased, and was significantly down-regulated after 96 h. Overall, our results further enriched the evidence that urea can stimulate cyanotoxin production, and ʟ-alanine could boost C. issatschenkoi proliferation, thus providing information for better management of aquatic systems. Moreover, by focusing on the intracellular C/N metabolic balance, this study explained the anatoxin production dynamics in C. issatschenkoi in response to different N sources.
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19
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Weisbrod B, Riehle E, Helmer M, Martin-Creuzburg D, Dietrich DR. Can toxin warfare against fungal parasitism influence short-term Dolichospermum bloom dynamics? - A field observation. HARMFUL ALGAE 2020; 99:101915. [PMID: 33218440 DOI: 10.1016/j.hal.2020.101915] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 08/20/2020] [Accepted: 10/04/2020] [Indexed: 06/11/2023]
Abstract
Cyanobacterial blooms often consist of numerous co-existing cyanobacterial species, with predominant taxa dynamically varying intra-annually. Parasitism by fungi (chytrids) has come into focus as an important factor driving short-term bloom dynamics. Using microscopic analysis, Illumina sequencing and cyanobacterial toxin analyses, we monitored the seasonal succession of Dolichospermum blooms in a reservoir along with environmental parameters. We identified two consecutive Dolichospermum blooms that were characterized by a straight and a coiled morphotype, separated by a complete bloom collapse. Phylotyping provided evidence for three putative Dolichospermum amplicon sequence variants (ASVs); i.e. Dolichospermum1 & 2 in the first bloom (straight filaments) and Dolichospermum3 in the second bloom (coiled filaments). Morphotype succession as well as total filament concentration did not correlate with any of the measured environmental parameters. Fungal parasitism by the chytrid Rhizosiphon crassum occurred in straight Dolichospermum filaments only. Coiled filaments showed no infection despite ambient presence of chytrids, deduced from fungal ASVs, throughout the entire observation period. Toxin concentrations (microcystins (MCs) and anabaenopeptins) correlated significantly with the abundance of the straight Dolichospermum morphotype. Enhanced cyanotoxin biosynthesis in the straight Dolichospermum morphotype, interpreted as a defensive reaction to fungal parasitism, appeared to come at the expense of lowered competitiveness with the co-occurring coiled morphotype. Our findings support the hypothesis that selective parasitism by chytrids is an important factor driving short-term morphotype and toxin dynamics within cyanobacterial blooms.
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Affiliation(s)
- B Weisbrod
- Human and Environmental Toxicology, University of Konstanz, Universitätsstrasse 10, 78464 Konstanz, Germany.
| | - E Riehle
- Human and Environmental Toxicology, University of Konstanz, Universitätsstrasse 10, 78464 Konstanz, Germany
| | - M Helmer
- Limnological Institute, University of Konstanz, Mainaustrasse 252, 78464 Konstanz, Germany
| | - D Martin-Creuzburg
- Limnological Institute, University of Konstanz, Mainaustrasse 252, 78464 Konstanz, Germany
| | - D R Dietrich
- Human and Environmental Toxicology, University of Konstanz, Universitätsstrasse 10, 78464 Konstanz, Germany
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20
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Christensen VG, Khan E. Freshwater neurotoxins and concerns for human, animal, and ecosystem health: A review of anatoxin-a and saxitoxin. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 736:139515. [PMID: 32485372 DOI: 10.1016/j.scitotenv.2020.139515] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 05/15/2020] [Accepted: 05/16/2020] [Indexed: 05/06/2023]
Abstract
Toxic cyanobacteria are a concern worldwide because they can adversely affect humans, animals, and ecosystems. However, neurotoxins produced by freshwater cyanobacteria are understudied relative to microcystin. Thus, the objective of this critical review was to provide a comprehensive examination of the modes of action, production, fate, and occurrence of the freshwater neurotoxins anatoxin-a and saxitoxin as they relate to human, animal, and ecosystem health. Literature on freshwater anatoxin-a and saxitoxin was obtained and reviewed for both laboratory and field studies. Current (2020) research identifies as many as 41 anatoxin-a producing species and 15 saxitoxin-producing species of freshwater cyanobacteria. Field studies indicate that anatoxin-a and saxitoxin have widespread distribution, and examples are given from every continent except Antarctica. Human and animal health concerns can range from acute to chronic. However, few researchers studied chronic or sublethal effects of freshwater exposures to anatoxin-a or saxitoxin. Ecosystem health also is a concern, as the effects of toxicity may be far reaching and include consequences throughout the food web. Several gaps in knowledge were identified for anatoxin-a and saxitoxin, including triggers of production and release, environmental fate and degradation, primary and secondary exposure routes, diel variation, food web effects, effects of cyanotoxin mixtures, and sublethal health effects on individual organisms and populations. Despite the gaps, this critical review facilitates our current understanding of freshwater neurotoxins and thus can serve to `` guide future research on anatoxin-a, saxitoxin, and other cyanotoxins.
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Affiliation(s)
- Victoria G Christensen
- U.S. Geological Survey, Upper Midwest Water Science Center, Mounds View, MN, USA; North Dakota State University, Environmental and Conservation Sciences Program, Fargo, ND, USA.
| | - Eakalak Khan
- Civil and Environmental Engineering and Construction Department, University of Nevada - Las Vegas, Las Vegas, NV, USA
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21
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Conklin KY, Stancheva R, Otten TG, Fadness R, Boyer GL, Read B, Zhang X, Sheath RG. Molecular and morphological characterization of a novel dihydroanatoxin-a producing Microcoleus species (cyanobacteria) from the Russian River, California, USA. HARMFUL ALGAE 2020; 93:101767. [PMID: 32307065 DOI: 10.1016/j.hal.2020.101767] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 01/22/2020] [Accepted: 01/28/2020] [Indexed: 06/11/2023]
Abstract
Reports of anatoxins poisoning of wildlife and domestic animals by toxigenic cyanobacteria in streams and rivers are increasing globally. Little is known about the taxonomy, morphology and genomics of anatoxins producing species, limiting our knowledge about their environmental preferences. We isolated three benthic non-heterocystous filamentous cyanobacterial strains from the Russian River in Northern California (USA), which produce anatoxin-a and dihydroanatoxin-a. Both 16S rRNA and protein sequence phylogenetic analyses showed that the strains represent a distinct new member of the cyanobacterial genus Microcoleus (Oscillatoriales). A novel species, Microcoleus anatoxicus is described and accompanied with light microscope photomicrographs, toxin profiles and the complete anatoxin-a gene cassette with the first description of the anaK gene in Microcoleus.
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Affiliation(s)
- Kimberly Y Conklin
- California State University San Marcos, 333 S. Twin Oaks Valley Rd., San Marcos, CA, 92096, USA
| | - Rosalina Stancheva
- California State University San Marcos, 333 S. Twin Oaks Valley Rd., San Marcos, CA, 92096, USA.
| | - Timothy G Otten
- Bend Genetics, 87 Scripps Dr Ste 301, Sacramento, CA, 95825, USA
| | - Rich Fadness
- North Coast Regional Water Quality Control Board, 5550 Skylane Blvd, Ste A, Santa Rosa, CA, 95403, USA
| | - Gregory L Boyer
- State University of New York - College of Environmental Science and Forestry, 1 Forestry Dr., Syracuse, NY, 13210, USA
| | - Betsy Read
- California State University San Marcos, 333 S. Twin Oaks Valley Rd., San Marcos, CA, 92096, USA
| | - Xiaoyu Zhang
- California State University San Marcos, 333 S. Twin Oaks Valley Rd., San Marcos, CA, 92096, USA
| | - Robert G Sheath
- California State University San Marcos, 333 S. Twin Oaks Valley Rd., San Marcos, CA, 92096, USA
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22
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Bownik A, Pawlik-Skowrońska B. Early indicators of behavioral and physiological disturbances in Daphnia magna (Cladocera) induced by cyanobacterial neurotoxin anatoxin-a. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 695:133913. [PMID: 31756843 DOI: 10.1016/j.scitotenv.2019.133913] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/30/2019] [Accepted: 08/12/2019] [Indexed: 05/23/2023]
Abstract
The majority of reports on the toxic effect of cyanobacterial metabolites on the freshwater invertebrates is based on determination of two endpoints: mortality or immobilization. However, detection of sub-lethal effects requires more sensitive indicators The aim of the present study was to evaluate the applicability of digital-video analysis for determination of early behavioral and physiological responses in the assessment of effects caused by the cyanobacterial neurotoxin, anatoxin-a (ANTX) at a broad range of its concentration (0.5-50 μg/mL). Swimming speed (SS), heart rate (HR), oxygen consumption (OC), thoracic limb activity (TLA) and abdominal claw movement (ACM) of Daphnia magna were evaluated. Swimming speed and abdominal claw movements were determined by digital analysis of video clips by Tracker® software; OC by Oxygraph Plus System® while HR, TLA and ACM by digital frame-by-frame analysis of video clips of microscopic view with the use of a media player software. The experimental study showed a concentration- and time-dependent decrease of SS, HR, OC, TLA and ACM. SS was inhibited as early as after 10 s of the exposure of Daphnia magna to ANTX, and the other physiological responses after 2 h. Further inhibition of these parameters was also noted after 24 h of the exposure. On the other hand, stimulation of ACM was noted at the lower (0.5 and 2.5 μg/mL) ANTX concentrations after both 2 h and 24 h of exposure. The results indicated that some behavioral and physiological biomarkers measured by video analysis may be a valuable tool for an early determination of toxic effects induced by cyanobacterial metabolites in zooplankters.
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Affiliation(s)
- Adam Bownik
- Department of Hydrobiology and Protection of Ecosystems, University of Life Sciences in Lublin, Dobrzańskiego 37, 20-262, Lublin, Poland.
| | - Barbara Pawlik-Skowrońska
- Department of Hydrobiology and Protection of Ecosystems, University of Life Sciences in Lublin, Dobrzańskiego 37, 20-262, Lublin, Poland
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23
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Salmaso N. Effects of Habitat Partitioning on the Distribution of Bacterioplankton in Deep Lakes. Front Microbiol 2019; 10:2257. [PMID: 31636614 PMCID: PMC6788347 DOI: 10.3389/fmicb.2019.02257] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 09/17/2019] [Indexed: 12/04/2022] Open
Abstract
In deep lakes, many investigations highlighted the existence of exclusive groups of bacteria adapted to deep oxygenated and hypoxic and anoxic hypolimnia. Nevertheless, the extent of bacterial strain diversity has been much less scrutinized. This aspect is essential for an unbiased estimation of genetic variation, biodiversity, and population structure, which are essential for studying important research questions such as biogeographical patterns, temporal and spatial variability and the environmental factors affecting this variability. This study investigated the bacterioplankton community in the epilimnetic layers and in the oxygenated and hypoxic/anoxic hypolimnia of five large and deep lakes located at the southern border of the Alps using high throughput sequencing (HTS) analyses (16S rDNA) and identification of amplicon sequence variants (ASVs) resolving reads differing by as little as one nucleotide. The study sites, which included two oligomictic (Garda and Como) and three meromictic lakes (Iseo, Lugano, and Idro) with maximum depths spanning from 124 to 410 m, were chosen among large lakes to represent an oxic-hypoxic gradient. The analyses showed the existence of several unique ASVs in the three layers of the five lakes. In the case of cyanobacteria, this confirmed previous analyses made at the level of strains or based on oligotyping methods. As expected, the communities in the hypoxic/anoxic monimolimnia showed a strong differentiation from the oxygenated layer, with the exclusive presence in single lakes of several unique ASVs. In the meromictic lakes, results supported the hypothesis that the formation of isolated monimolimnia sustained the development of highly diversified bacterial communities through ecological selection, leading to the establishment of distinctive biodiversity zones. The genera identified in these layers are well-known to activate a wide range of redox reactions at low O2 conditions. As inferred from 16S rDNA data, the highly diversified and coupled processes sustained by the monimolimnetic microbiota are essential ecosystem services that enhance mineralization of organic matter and formation of reduced compounds, and also abatement of undesirable greenhouse gasses.
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Affiliation(s)
- Nico Salmaso
- Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Italy
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The Diversity of Cyanobacterial Toxins on Structural Characterization, Distribution and Identification: A Systematic Review. Toxins (Basel) 2019; 11:toxins11090530. [PMID: 31547379 PMCID: PMC6784007 DOI: 10.3390/toxins11090530] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 09/06/2019] [Accepted: 09/09/2019] [Indexed: 11/19/2022] Open
Abstract
The widespread distribution of cyanobacteria in the aquatic environment is increasing the risk of water pollution caused by cyanotoxins, which poses a serious threat to human health. However, the structural characterization, distribution and identification techniques of cyanotoxins have not been comprehensively reviewed in previous studies. This paper aims to elaborate the existing information systematically on the diversity of cyanotoxins to identify valuable research avenues. According to the chemical structure, cyanotoxins are mainly classified into cyclic peptides, alkaloids, lipopeptides, nonprotein amino acids and lipoglycans. In terms of global distribution, the amount of cyanotoxins are unbalanced in different areas. The diversity of cyanotoxins is more obviously found in many developed countries than that in undeveloped countries. Moreover, the threat of cyanotoxins has promoted the development of identification and detection technology. Many emerging methods have been developed to detect cyanotoxins in the environment. This communication provides a comprehensive review of the diversity of cyanotoxins, and the detection and identification technology was discussed. This detailed information will be a valuable resource for identifying the various types of cyanotoxins which threaten the environment of different areas. The ability to accurately identify specific cyanotoxins is an obvious and essential aspect of cyanobacterial research.
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John N, Baker L, Ansell BRE, Newham S, Crosbie ND, Jex AR. First report of anatoxin-a producing cyanobacteria in Australia illustrates need to regularly up-date monitoring strategies in a shifting global distribution. Sci Rep 2019; 9:10894. [PMID: 31350418 PMCID: PMC6659621 DOI: 10.1038/s41598-019-46945-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 07/03/2019] [Indexed: 11/09/2022] Open
Abstract
Routine monitoring of toxic cyanobacteria depends on up-to-date epidemiological information about their distribution. In Australia, anatoxin producing cyanobacteria are not regularly tested for and thought to be rare if not absent from the continent. Our study investigated the presence of anatoxin-a (ATX-a) producing cyanobacteria in surface water samples (n = 226 from 67 sampling locations) collected from 2010 to 2017 across the state of Victoria, Australia. We (1) detected the presence and distribution of anaC (anatoxin-a synthetase C) gene sequences previously associated with various cyanobacteria, including Cuspidothrix issatschenkoi, Aphanizomenon sp., D. circinale, Anabaena sp., and Oscillatoria sp., from 31 sampling locations, and (2) determined the concentration of ATX-a in samples tested using ELISA, in two instances detected at >4 µg · L-1. These data present the first confirmation of ATX-a producers in Australia. Our study indicates that ATX-a should be included in regular testing of cyanobacterial blooms in Australia and highlights the importance of regular investigation of the distributions of toxic cyanobacteria worldwide, particularly amid the known expanding distribution of many cyanobacterial taxa in a period of increased eutrophication and rising surface water temperatures.
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Affiliation(s)
- Nijoy John
- Department of Veterinary Biosciences, The University of Melbourne, Parkville, Victoria, 3010, Australia.
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia.
| | - Louise Baker
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia
| | - Brendan R E Ansell
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia
| | - Steven Newham
- Goulburn Valley Water, Shepparton, Victoria, 3630, Australia
| | - Nicholas D Crosbie
- Melbourne Water, Docklands, Victoria, 3008, Australia
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Aaron R Jex
- Department of Veterinary Biosciences, The University of Melbourne, Parkville, Victoria, 3010, Australia
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia
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Svirčev Z, Lalić D, Bojadžija Savić G, Tokodi N, Drobac Backović D, Chen L, Meriluoto J, Codd GA. Global geographical and historical overview of cyanotoxin distribution and cyanobacterial poisonings. Arch Toxicol 2019; 93:2429-2481. [DOI: 10.1007/s00204-019-02524-4] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 07/18/2019] [Indexed: 10/26/2022]
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Ballot A, Scherer PI, Wood SA. Variability in the anatoxin gene clusters of Cuspidothrix issatschenkoi from Germany, New Zealand, China and Japan. PLoS One 2018; 13:e0200774. [PMID: 30024929 PMCID: PMC6053186 DOI: 10.1371/journal.pone.0200774] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 07/03/2018] [Indexed: 11/18/2022] Open
Abstract
Anatoxin-a and homoanatoxin-a are neurotoxic cyanotoxins produced by benthic and planktonic cyanobacteria worldwide. These toxins are produced by the cyanobacterial genera Dolichospermum, Cuspidothrix, Phormidium, Oscillatoria, Tychonema and Cylindrospermum. In the present study the ana gene clusters (anaA-anaG; c. 21.1 kilobases) of two anatoxin producing Cuspidothrix issatschenkoi strains from Germany: (NIVA-CYA 711) and New Zealand (CAWBG02) were sequenced and compared with the ana gene clusters of two C. issatschenkoi strains from Japan (RM-6 and LBRI48) and one from China (CHABD3). All five ana gene clusters are characterized by the same gene order for anaA-anaG. Similarities were highest (99.56–99.57%) between German (NIVA-CYA 711), New Zealand (CAWBG02) and Chinese (CHABD3) strains. Similarities were lower (91.40–91.67%) when compared to the Japanese strains (RM-6 and LBRI48). Collectively, 2,037 variable sites (328 single nucleotide polymorphisms and 9 insertions/deletions, comprising 1,709 nucleotides) were found in the ana gene clusters of the German, New Zealand and Japanese strains compared to the Chinese strain (CHABD3). The ana gene clusters of the German (NIVA-CYA 711), New Zealand (CAWBG02) and Japanese (RM-6 and LBRI48) strains were characterized by 83, 84, 255 and 231 SNP’s compared to the Chinese strain (CHABD3), respectively. The anaE and anaF genes showed the highest variability in all five strains and are recommended as the best genetic markers for further phylogenetic studies of the ana gene cluster from C. issatschenkoi.
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Affiliation(s)
- Andreas Ballot
- Norwegian Institute for Water Research, Oslo, Norway
- * E-mail:
| | - Pia I. Scherer
- Limnological Research Station Iffeldorf, Technical University of Munich, Munich, Germany
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Salmaso N, Albanese D, Capelli C, Boscaini A, Pindo M, Donati C. Diversity and Cyclical Seasonal Transitions in the Bacterial Community in a Large and Deep Perialpine Lake. MICROBIAL ECOLOGY 2018; 76:125-143. [PMID: 29192335 DOI: 10.1007/s00248-017-1120-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Accepted: 11/22/2017] [Indexed: 06/07/2023]
Abstract
High-throughput sequencing (HTS) was used to analyze the seasonal variations in the bacterioplankton community composition (BCC) in the euphotic layer of a large and deep lake south of the Alps (Lake Garda). The BCC was analyzed throughout two annual cycles by monthly samplings using the amplification and sequencing of the V3-V4 hypervariable region of the 16S rRNA gene by the MiSeq Illumina platform. The dominant and most diverse bacterioplankton phyla were among the more frequently reported in freshwater ecosystems, including the Proteobacteria, Cyanobacteria, Bacteroidetes, Verrucomicrobia, Actinobacteria, and Planctomycetes. As a distinctive feature, the development of the BCC showed a cyclical temporal pattern in the two analyzed years and throughout the euphotic layer. The recurring temporal development was controlled by the strong seasonality in water temperature and thermal stratification, and by cyclical temporal changes in nutrients and, possibly, by the remarkable annual cyclical development of cyanobacteria and eukaryotic phytoplankton hosting bacterioplankton that characterizes Lake Garda. Further downstream analyses of operational taxonomic units associated to cyanobacteria allowed confirming the presence of the most abundant taxa previously identified by microscopy and/or phylogenetic analyses, as well as the presence of other small Synechococcales/Chroococcales and rare Nostocales never identified so far in the deep lakes south of the Alps. The implications of the high diversity and strong seasonality are relevant, opening perspectives for the definition of common and discriminating patterns characterizing the temporal and spatial distribution in the BCC, and for the application of the new sequencing technologies in the monitoring of water quality in large and deep lakes.
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Affiliation(s)
- Nico Salmaso
- Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010, San Michele all'Adige, Italy.
| | - Davide Albanese
- Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010, San Michele all'Adige, Italy
| | - Camilla Capelli
- Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010, San Michele all'Adige, Italy
| | - Adriano Boscaini
- Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010, San Michele all'Adige, Italy
| | - Massimo Pindo
- Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010, San Michele all'Adige, Italy
| | - Claudio Donati
- Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010, San Michele all'Adige, Italy
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Foss AJ, Butt J, Aubel MT. Benthic periphyton from Pennsylvania, USA is a source for both hepatotoxins (microcystins/nodularin) and neurotoxins (anatoxin-a/homoanatoxin-a). Toxicon 2018; 150:13-16. [PMID: 29746979 DOI: 10.1016/j.toxicon.2018.05.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 05/01/2018] [Accepted: 05/02/2018] [Indexed: 11/27/2022]
Abstract
In 2016, the Pennsylvania Department of Environmental Protection conducted a limited survey of streams in the Susquehanna River basin in Pennsylvania, USA, to screen for microcystins/nodularins, anatoxin-a (ATX) and homoanatoxin-a (HTX). Testing revealed the presence of HTX in samples collected from the Pine Creek basin, with ATX present at lower levels. Microcystins/nodularins (MCs/NODs) were also tested and found to be concomitant, with NOD-R confirmed present by LC-MS/MS.
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Affiliation(s)
- Amanda J Foss
- GreenWater Laboratories/CyanoLab, 205 Zeagler Drive, Palatka, FL 32177, USA.
| | - Jeffery Butt
- Pennsylvania Department of Environmental Protection, Bureau of Clean Water, Rachel Carson State Office Building, 400 Market Street, Harrisburg, PA 17101, USA.
| | - Mark T Aubel
- GreenWater Laboratories/CyanoLab, 205 Zeagler Drive, Palatka, FL 32177, USA
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Fastner J, Beulker C, Geiser B, Hoffmann A, Kröger R, Teske K, Hoppe J, Mundhenk L, Neurath H, Sagebiel D, Chorus I. Fatal Neurotoxicosis in Dogs Associated with Tychoplanktic, Anatoxin-a Producing Tychonema sp. in Mesotrophic Lake Tegel, Berlin. Toxins (Basel) 2018; 10:toxins10020060. [PMID: 29385106 PMCID: PMC5848161 DOI: 10.3390/toxins10020060] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 01/19/2018] [Accepted: 01/22/2018] [Indexed: 11/27/2022] Open
Abstract
In May 2017, at least 12 dogs showed signs of acute neurotoxicosis after swimming in or drinking from Lake Tegel, a mesotrophic lake in Berlin, Germany, and several of the affected dogs died shortly afterwards despite intensive veterinary treatment. Cyanobacterial blooms were not visible at the water surface or the shorelines. However, detached and floating water moss (Fontinalis antipyretica) with high amounts of Tychonema sp., a potential anatoxin-a (ATX) producing cyanobacterium, was found near the beaches where the dogs had been swimming and playing. Necropsies of two of the dogs revealed no specific lesions beside the anamnestic neurotoxicosis. ATX was detected in concentrations up to 8700 µg L−1 in the stomach contents, while other (neuro)toxic substances were not found. In the aqueous fraction of Fontinalis/Tychonema clumps sampled after the casualties, ATX was found in concentrations up to 1870 µg L−1. This is the first report of a dense population of Tychonema sp. in stands of Fontinalis resulting in high ATX contents. This case emphasizes the need for further investigation of potentially toxic, non-bloom forming cyanobacteria in less eutrophic water bodies and underlines the novel challenge of developing appropriate surveillance schemes for respective bathing sites.
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Affiliation(s)
- Jutta Fastner
- German Environment Agency, Corrensplatz 1, 14195 Berlin, Germany.
| | - Camilla Beulker
- Berlin Brandenburg State Laboratory Abt. IV, Invalidenstr. 60, 10557 Berlin, Germany.
| | | | - Anja Hoffmann
- Berlin Brandenburg State Laboratory Abt. IV, Invalidenstr. 60, 10557 Berlin, Germany.
| | - Roswitha Kröger
- State Office for Health & Social Affairs (LAGeSo), Working Group Water Hygiene & Environmental Health, Postfach 31-09-29, 10639 Berlin, Germany.
| | - Kinga Teske
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Strasse 15, 14163 Berlin, Germany.
| | - Judith Hoppe
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Strasse 15, 14163 Berlin, Germany.
| | - Lars Mundhenk
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Strasse 15, 14163 Berlin, Germany.
| | - Hartmud Neurath
- Toxicological Laboratory, Medical University Center, 37075 Göttingen, Germany.
| | - Daniel Sagebiel
- State Office for Health & Social Affairs (LAGeSo), Working Group Water Hygiene & Environmental Health, Postfach 31-09-29, 10639 Berlin, Germany.
| | - Ingrid Chorus
- German Environment Agency, Corrensplatz 1, 14195 Berlin, Germany.
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31
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Belykh OI, Fedorova GA, Kuzmin AV, Tikhonova IV, Timoshkin OA, Sorokovikova EG. Microcystins in Cyanobacterial Biofilms from the Littoral Zone of Lake Baikal. ACTA ACUST UNITED AC 2018. [DOI: 10.3103/s0096392517040022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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32
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Interspecific Relationship and Ecological Requirements of Two Potentially Harmful Cyanobacteria in a Deep South-Alpine Lake (L. Iseo, I). WATER 2017. [DOI: 10.3390/w9120993] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Qian ZY, Ma J, Sun CL, Li ZG, Xian QM, Gong TT, Xu B. Using stable isotope labeling to study the nitrogen metabolism in Anabaena flos-aquae growth and anatoxin biosynthesis. WATER RESEARCH 2017; 127:223-229. [PMID: 29055827 DOI: 10.1016/j.watres.2017.09.060] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 09/25/2017] [Accepted: 09/30/2017] [Indexed: 06/07/2023]
Abstract
Freshwater resources are under stress around the world due to rapid urbanization and excessive water consumption. Cyanobacterial blooms have occurred frequently in surface waters, which produced toxic secondary metabolites causing a potential harm to aquatic ecosystems and humans. In this study, the relationship between different types of nitrogen source and the algal growth of Anabaena flos-aquae, which was isolated from Dianchi Lake in southern China, was investigated. Experiments were accomplished by using four types of isotope tracers including 15N-ammonium chloride, 15N-sodium nitrate, 15N-urea, 15N-l-alanine in culture medium to characterize the biosynthesis of 15N-anatoxin-a (ATX-A), which is a major algal toxin from A. flos-aquae, through liquid chromatography-tandem mass spectrometry (LC-MS/MS). The results showed that all these four types of nitrogen can be incorporated into algal cells. The ATX-A production with urea as the nitrogen source was much higher than that with the other three types of nitrogen. The 15N labeling experiments further demonstrated that the uptake of organic nitrogen nutrients was significantly greater than that of inorganic nitrogen. These results provide new evidence and deeper insight to explore the biosynthesis of ATX-A in the specific strain of A. flos-aquae.
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Affiliation(s)
- Zong-Yao Qian
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China; Institute of Agricultural Quality Standards and Testing Technology Research, Xinjiang Academy of Agricultural Science, Xinjiang 830091, PR China
| | - Jian Ma
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Chun-Lei Sun
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Zhi-Gang Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Qi-Ming Xian
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China.
| | - Ting-Ting Gong
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China.
| | - Bin Xu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
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Draft Genome Sequence of the Planktic Cyanobacterium Tychonema bourrellyi, Isolated from Alpine Lentic Freshwater. GENOME ANNOUNCEMENTS 2017; 5:5/47/e01294-17. [PMID: 29167244 PMCID: PMC5701469 DOI: 10.1128/genomea.01294-17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We describe here the draft genome sequence of the cyanobacterium Tychonema bourrellyi, assembled from a metagenome of a nonaxenic culture. The strain (FEM_GT703) was isolated from a freshwater sample taken from Lake Garda, Italy. The draft genome sequence represents the first assembled T. bourrellyi strain.
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Funari E, Manganelli M, Buratti FM, Testai E. Cyanobacteria blooms in water: Italian guidelines to assess and manage the risk associated to bathing and recreational activities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 598:867-880. [PMID: 28458204 DOI: 10.1016/j.scitotenv.2017.03.232] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 03/23/2017] [Accepted: 03/25/2017] [Indexed: 06/07/2023]
Abstract
Cyanobacteria thrive in many aquatic environments, where they can produce cyanotoxins with different toxicological profile. Anthropic pressure and climate changes are causing the expansion in terms of time and space of their blooms, increasing the concerns for human health in several exposure scenarios. Here the update of the Italian guidelines for the management of cyanobacterial blooms in bathing water is presented. A risk-based approach has been developed according to the current scientific knowledge on cyanobacteria distribution in the Italian Lakes and on chemical, toxicological and epidemiological aspects of different cyanotoxins, summarized in the first part of the paper. Oral, dermal and inhalation exposure to cyanotoxins, during recreational activities, are individually examined, to develop a framework of thresholds and actions aimed at preventing harmful effects for bathers. Guidelines, also by comparing international guidance values and/or guidelines, provide criteria to plan environmental monitoring activities, health surveillance and public communication systems. Finally the still important scientific gaps and research needs are highlighted.
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Affiliation(s)
- Enzo Funari
- Istituto Superiore di Sanità, Dept. of Environment and Health, Viale Regina Elena 299, 00161 Rome, Italy.
| | - Maura Manganelli
- Istituto Superiore di Sanità, Dept. of Environment and Health, Viale Regina Elena 299, 00161 Rome, Italy.
| | - Franca M Buratti
- Istituto Superiore di Sanità, Dept. of Environment and Health, Viale Regina Elena 299, 00161 Rome, Italy.
| | - Emanuela Testai
- Istituto Superiore di Sanità, Dept. of Environment and Health, Viale Regina Elena 299, 00161 Rome, Italy.
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Capelli C, Ballot A, Cerasino L, Papini A, Salmaso N. Biogeography of bloom-forming microcystin producing and non-toxigenic populations of Dolichospermum lemmermannii (Cyanobacteria). HARMFUL ALGAE 2017; 67:1-12. [PMID: 28755712 DOI: 10.1016/j.hal.2017.05.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 03/17/2017] [Accepted: 05/06/2017] [Indexed: 06/07/2023]
Abstract
In the last decades, the cyanobacterium Dolichospermum lemmermannii showed an increasing spread to Southern Europe, raising serious concerns due to its ability to produce cyanotoxins. The widening of its geographic distribution and the observation of strains showing high optimum temperature underline its ecological heterogeneity, suggesting the existence of different ecotypes. To investigate its biogeography, new isolates from different European water bodies, together with strains maintained by the Norwegian Institute for Water Research Culture Collection of Algae, were genetically characterised for the 16S rRNA gene and compared with strains obtained from public repositories. Geographic distance highly influenced the differentiation of genotypes, further suggesting the concurrent role of geographic isolation, physical barriers and environmental factors in promoting the establishment of phylogenetic lineages adapted to specific habitats. Differences among populations were also examined by morphological analysis and evaluating the toxic potential of single strains, which revealed the exclusive ability of North European strains to produce microcystins, whereas the populations in Southern Europe tested negative for a wide range of cyanotoxins. The high dispersion ability and the existence of toxic genotypes indicate the possible spread of harmful blooms in other temperate regions.
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Affiliation(s)
- Camilla Capelli
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all'Adige, TN, Italy; Department of Biology, University of Florence, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Firenze, Italy.
| | - Andreas Ballot
- Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349 Oslo, Norway
| | - Leonardo Cerasino
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all'Adige, TN, Italy
| | - Alessio Papini
- Department of Biology, University of Florence, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Firenze, Italy
| | - Nico Salmaso
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all'Adige, TN, Italy
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Shunmugam S, Gayathri M, Prasannabalaji N, Thajuddin N, Muralitharan G. Unraveling the presence of multi-class toxins from Trichodesmium bloom in the Gulf of Mannar region of the Bay of Bengal. Toxicon 2017; 135:43-50. [PMID: 28606423 DOI: 10.1016/j.toxicon.2017.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 05/23/2017] [Accepted: 06/06/2017] [Indexed: 12/23/2022]
Abstract
Trichodesmium is an enigmatic bloom forming, non-heterocystous cyanobacterium reported most frequently in the coastal waters of India. However, the toxigenic potential of this globally significant N2 fixing cyanobacterium has not been characterized. In this study, we report for the first time the presence of potent multi-class neurotoxins such as Anatoxin-a, Saxitoxins, Gonyautoxin and hepatotoxins like MC-LR, MC-YA from a bloom material of Trichodesmium sp. MBDU 524 collected at the Gulf of Mannar region. Toxins were determined using liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) analysis of HPLC purified aqueous and solvent fractions. Molecular phylogenetic analysis through 16S rRNA gene sequencing showed the close relationship with Trichodesmium erythraeum clade. The toxigenic potential was validated through brine shrimp toxicity assay and showed 100% mortality after 48 h of incubation. The results suggest the potential toxigenic and environmental impacts of Trichodesmium bloom sample from the Gulf of Mannar region.
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Affiliation(s)
- Sumathy Shunmugam
- Department of Microbiology, Centre of Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli, 620024, Tamilnadu, India
| | - Manickam Gayathri
- Department of Microbiology, Centre of Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli, 620024, Tamilnadu, India
| | - Nainangu Prasannabalaji
- Department of Microbiology, Centre of Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli, 620024, Tamilnadu, India
| | - Nooruddin Thajuddin
- Department of Microbiology, Centre of Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli, 620024, Tamilnadu, India
| | - Gangatharan Muralitharan
- Department of Microbiology, Centre of Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli, 620024, Tamilnadu, India.
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Buratti FM, Manganelli M, Vichi S, Stefanelli M, Scardala S, Testai E, Funari E. Cyanotoxins: producing organisms, occurrence, toxicity, mechanism of action and human health toxicological risk evaluation. Arch Toxicol 2017; 91:1049-1130. [DOI: 10.1007/s00204-016-1913-6] [Citation(s) in RCA: 258] [Impact Index Per Article: 36.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 12/13/2016] [Indexed: 12/11/2022]
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Affiliation(s)
- Junguo Ma
- College of Life Science, Henan Normal University, Xinxiang, China
| | - Xiaoyu Li
- College of Life Science, Henan Normal University, Xinxiang, China
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40
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Legrand B, Lesobre J, Colombet J, Latour D, Sabart M. Molecular tools to detect anatoxin-a genes in aquatic ecosystems: Toward a new nested PCR-based method. HARMFUL ALGAE 2016; 58:16-22. [PMID: 28073454 DOI: 10.1016/j.hal.2016.07.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 07/11/2016] [Accepted: 07/12/2016] [Indexed: 06/06/2023]
Abstract
Over the last few decades, cyanobacterial mass occurrence has become a recurrent feature of aquatic ecosystems. This has led to ecosystem exposure and health hazards associated with cyanotoxin production. The neurotoxin anatoxin-a and its homologs can be synthesized by benthic cyanobacterial species in lotic systems, but also by planktonic lacustrine species such as Dolichospermum (also known as Anabaena). However, only a few studies have focused on anatoxin-a occurrence and its biosynthesis genes in freshwater lakes. The initial aim of this study was to evaluate the molecular tools available in the literature to detect anatoxin-a biosynthesis genes in lacustrine environments. Having tested different sets of PCR primers, we found that that some sets of primers, such as anxC, were too specific and did not amplify anatoxin-a biosynthesis genes in all producing strains. On the other hand, some sets of primers, such as atxoa, seemed not to be specific enough, amplifying numerous non-specific bands in environmental samples, especially those from sediments. Furthermore, anaC and anaF amplification exhibited different band intensities during electrophoresis, suggesting a high variation in number of gene copies between samples. As a result, we proposed a new nested PCR-based method which considerably improved the amplification of the anaC gene in our environmental samples, eliminating non-specific bands and weak detections. Using this tool, our study also highlighted that anatoxin-a genes are widely distributed throughout freshwater lakes. This suggests the need for further ecological investigations into anatoxin-a in these ecosystems.
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Affiliation(s)
- Benjamin Legrand
- Université Clermont Auvergne, Université Blaise Pascal, LMGE, BP 10448, Clermont-Ferrand F-63000, France; CNRS, UMR 6023, LMGE, Campus Universitaire des Cézeaux, France; Athos-Environnement, 112 Avenue du Brézet, Clermont-Ferrand F-63100, France.
| | - Jerome Lesobre
- Université Clermont Auvergne, Université Blaise Pascal, LMGE, BP 10448, Clermont-Ferrand F-63000, France; CNRS, UMR 6023, LMGE, Campus Universitaire des Cézeaux, France
| | - Jonathan Colombet
- Université Clermont Auvergne, Université Blaise Pascal, LMGE, BP 10448, Clermont-Ferrand F-63000, France; CNRS, UMR 6023, LMGE, Campus Universitaire des Cézeaux, France
| | - Delphine Latour
- Université Clermont Auvergne, Université Blaise Pascal, LMGE, BP 10448, Clermont-Ferrand F-63000, France; CNRS, UMR 6023, LMGE, Campus Universitaire des Cézeaux, France
| | - Marion Sabart
- Université Clermont Auvergne, Université Blaise Pascal, LMGE, BP 10448, Clermont-Ferrand F-63000, France; CNRS, UMR 6023, LMGE, Campus Universitaire des Cézeaux, France
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Salmaso N, Cerasino L, Boscaini A, Capelli C. PlankticTychonema(Cyanobacteria) in the large lakes south of the Alps: phylogenetic assessment and toxigenic potential. FEMS Microbiol Ecol 2016; 92:fiw155. [DOI: 10.1093/femsec/fiw155] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/08/2016] [Indexed: 12/24/2022] Open
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Kurmayer R, Deng L, Entfellner E. Role of toxic and bioactive secondary metabolites in colonization and bloom formation by filamentous cyanobacteria Planktothrix. HARMFUL ALGAE 2016; 54:69-86. [PMID: 27307781 PMCID: PMC4892429 DOI: 10.1016/j.hal.2016.01.004] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 01/15/2016] [Accepted: 01/15/2016] [Indexed: 05/22/2023]
Abstract
Bloom-forming cyanobacteria Planktothrix agardhii and P. rubescens are regularly involved in the occurrence of cyanotoxin in lakes and reservoirs. Besides microcystins (MCs), which inhibit eukaryotic protein phosphatase 1 and 2A, several families of bioactive peptides are produced, thereby resulting in impressive secondary metabolite structural diversity. This review will focus on the current knowledge of the phylogeny, morphology, and ecophysiological adaptations of Planktothrix as well as the toxins and bioactive peptides produced. The relatively well studied ecophysiological adaptations (buoyancy, shade tolerance, nutrient storage capacity) can partly explain the invasiveness of this group of cyanobacteria that bloom within short periods (weeks to months). The more recent elucidation of the genetic basis of toxin and bioactive peptide synthesis paved the way for investigating its regulation both in the laboratory using cell cultures as well as under field conditions. The high frequency of several toxin and bioactive peptide synthesis genes observed within P. agardhii and P. rubescens, but not for other Planktothrix species (e.g. P. pseudagardhii), suggests a potential functional linkage between bioactive peptide production and the colonization potential and possible dominance in habitats. It is hypothesized that, through toxin and bioactive peptide production, Planktothrix act as a niche constructor at the ecosystem scale, possibly resulting in an even higher ability to monopolize resources, positive feedback loops, and resilience under stable environmental conditions. Thus, refocusing harmful algal bloom management by integrating ecological and phylogenetic factors acting on toxin and bioactive peptide synthesis gene distribution and concentrations could increase the predictability of the risks originating from Planktothrix blooms.
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Affiliation(s)
- Rainer Kurmayer
- University of Innsbruck, Research Institute for Limnology, Mondseestrasse 9, 5310 Mondsee, Austria.
| | - Li Deng
- Helmholtz Zentrum München, Institute of Groundwater Ecology, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Elisabeth Entfellner
- University of Innsbruck, Research Institute for Limnology, Mondseestrasse 9, 5310 Mondsee, Austria
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Testai E, Scardala S, Vichi S, Buratti FM, Funari E. Risk to human health associated with the environmental occurrence of cyanobacterial neurotoxic alkaloids anatoxins and saxitoxins. Crit Rev Toxicol 2016; 46:385-419. [PMID: 26923223 DOI: 10.3109/10408444.2015.1137865] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Cyanobacteria are ubiquitous photosynthetic micro-organisms forming blooms and scums in surface water; among them some species can produce cyanotoxins giving rise to some concern for human health and animal life. To date, more than 65 cyanobacterial neurotoxins have been described, of which the most studied are the groups of anatoxins and saxitoxins (STXs), comprising many different variants. In freshwaters, the hepatotoxic microcystins represent the most frequently detected cyanotoxin: on this basis, it could appear that neurotoxins are less relevant, but the low frequency of detection may partially reflect an a priori choice of target analytes, the low method sensitivity and the lack of certified standards. Cyanobacterial neurotoxins target cholinergic synapses or voltage-gated ion channels, blocking skeletal and respiratory muscles, thus leading to death by respiratory failure. This review reports and analyzes the available literature data on environmental occurrence of cyanobacterial neurotoxic alkaloids, namely anatoxins and STXs, their biosynthesis, toxicology and epidemiology, derivation of guidance values and action limits. These data are used as the basis to assess the risk posed to human health, identify critical exposure scenarios and highlight the major data gaps and research needs.
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Affiliation(s)
- Emanuela Testai
- a Environment and Primary Prevention Department , Istituto Superiore di Sanità , Rome , Italy
| | - Simona Scardala
- a Environment and Primary Prevention Department , Istituto Superiore di Sanità , Rome , Italy
| | - Susanna Vichi
- a Environment and Primary Prevention Department , Istituto Superiore di Sanità , Rome , Italy
| | - Franca M Buratti
- a Environment and Primary Prevention Department , Istituto Superiore di Sanità , Rome , Italy
| | - Enzo Funari
- a Environment and Primary Prevention Department , Istituto Superiore di Sanità , Rome , Italy
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Bao T, Chen T, Wille ML, Chen D, Wu W, Frost RL. Performance and characterization of a non-sintered zeolite porous filter for the simultaneous removal of nitrogen and phosphorus in a biological aerated filter (BAF). RSC Adv 2016. [DOI: 10.1039/c6ra05417j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A novel non-sintered zeolite porous filter (ZPF) and commercially available ceramsite (CAC) are used to investigate the simultaneous removal of nitrogen and phosphorus from city wastewater treated by biological aerated filter (BAF) reactors.
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Affiliation(s)
- Teng Bao
- Laboratory for Nanominerals and Environmental Material
- School of Resource and Environmental Engineering
- Hefei University of Technology
- China
- School of Chemistry
| | - Tianhu Chen
- Laboratory for Nanominerals and Environmental Material
- School of Resource and Environmental Engineering
- Hefei University of Technology
- China
| | - Marie-Luise Wille
- Institute of Health & Biomedical Innovation
- Queensland University of Technology
- Brisbane
- Australia
| | - Dong Chen
- Laboratory for Nanominerals and Environmental Material
- School of Resource and Environmental Engineering
- Hefei University of Technology
- China
| | - Wentao Wu
- Laboratory for Nanominerals and Environmental Material
- School of Resource and Environmental Engineering
- Hefei University of Technology
- China
| | - Ray L. Frost
- School of Chemistry
- Physics and Mechanical Engineering
- Science and Engineering Faculty
- Queensland University of Technology
- Australia
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Wang S, Zhu L, Li Q, Li G, Li L, Song L, Gan N. Distribution and population dynamics of potential anatoxin-a-producing cyanobacteria in Lake Dianchi, China. HARMFUL ALGAE 2015; 48:63-68. [PMID: 29724477 DOI: 10.1016/j.hal.2015.07.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 07/07/2015] [Accepted: 07/07/2015] [Indexed: 06/08/2023]
Abstract
The occurrence of cyanobacterial blooms is often accompanied by a variety of toxic secondary metabolites known as cyanotoxins. Anatoxin-a (ATX-a) is a highly toxic cyanobacterial neurotoxin synthesized by numerous species (e.g., Aphanizomenon, Anabaena and Oscillatoria) that has received much public attention. In this study, we used molecular methods (PCR and qPCR) to track the presence and dynamics of ATX-a-producing cyanobacteria, Aphanizomenon and Anabaena in Lake Dianchi, China based on the anaC and cpcBA-IGS genes over a 23-month period (from June 2010 to April 2012). Results revealed that Aphanizomenon was the major potential ATX-a producer in Lake Dianchi and that they were most abundant in early spring and least abundant in summer, coinciding with observed Aphanizomenon blooms. It was found that the proportion of ATX-a toxigenic cells was lower in the northern part of the lake (2.1%) than the middle (16.7%) and southern parts (19.2%). The information on the spatio-temporal distributions of ATX-a-producing cyanobacteria obtained in this study will help to build management strategies to improve water quality for public health.
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Affiliation(s)
- Suqin Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Lin Zhu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Qi Li
- Wuhan Foreign Language School, Wansongyuan Road 48, Wuhan 430022, PR China
| | - Genbao Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, PR China.
| | - Lin Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Lirong Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Nanqin Gan
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, PR China.
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