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Biessy L, Pearman JK, Mertens KN, Réveillon D, Savar V, Hess P, Hampton H, Thompson L, Lebrun L, Terre-Terrillon A, Smith KF. Sudden peak in tetrodotoxin in French oysters during the summer of 2021: Source investigation using microscopy, metabarcoding and droplet digital PCR. Toxicon 2024; 243:107721. [PMID: 38636612 DOI: 10.1016/j.toxicon.2024.107721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 04/10/2024] [Accepted: 04/12/2024] [Indexed: 04/20/2024]
Abstract
Tetrodotoxin (TTX) is a potent neurotoxin causing human intoxications from contaminated seafood worldwide and is of emerging concern in Europe. Shellfish have been shown to contain varying TTX concentrations globally, with concentrations typically higher in Pacific oysters Crassostrea gigas in Europe. Despite many decades of research, the source of TTX remains unknown, with bacterial or algal origins having been suggested. The aim of this study was to identify potential source organisms causing TTX contamination in Pacific oysters in French coastal waters, using three different techniques. Oysters were deployed in cages from April to September 2021 in an estuary where TTX was previously detected. Microscopic analyses of water samples were used to investigate potential microalgal blooms present prior or during the peak in TTX. Differences in the bacterial communities from oyster digestive glands (DG) and remaining flesh were explored using metabarcoding, and lastly, droplet digital PCR assays were developed to investigate the presence of Cephalothrix sp., one European TTX-bearing species in the DG of toxic C. gigas. Oysters analysed by liquid chromatography-tandem mass spectrometry contained quantifiable levels of TTX over a three-week period (24 June-15 July 2021), with concentrations decreasing in the DG from 424 μg/kg for the first detection to 101 μg/kg (equivalent to 74 to 17 μg/kg of total flesh), and trace levels being detected until August 13, 2021. These concentrations are the first report of the European TTX guidance levels being exceeded in French shellfish. Microscopy revealed that some microalgae bloomed during the TTX peak, (e.g., Chaetoceros spp., reaching 40,000 cells/L). Prokaryotic metabarcoding showed increases in abundance of Rubritaleaceae (genus Persicirhabdus) and Neolyngbya, before and during the TTX peak. Both phyla have previously been described as possible TTX-producers and should be investigated further. Droplet digital PCR analyses were negative for the targeted TTX-bearing genus Cephalothrix.
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Affiliation(s)
- Laura Biessy
- Cawthron Institute, Private Bag 2, Nelson, 7010, New Zealand.
| | - John K Pearman
- Cawthron Institute, Private Bag 2, Nelson, 7010, New Zealand
| | - Kenneth Neil Mertens
- Ifremer, LITTORAL Unit, Place de la Croix, BP40537, 29900, Concarneau CEDEX, France
| | | | | | | | - Hannah Hampton
- Cawthron Institute, Private Bag 2, Nelson, 7010, New Zealand
| | - Lucy Thompson
- Cawthron Institute, Private Bag 2, Nelson, 7010, New Zealand
| | - Luc Lebrun
- Ifremer, LITTORAL Unit, Place de la Croix, BP40537, 29900, Concarneau CEDEX, France
| | | | - Kirsty F Smith
- Cawthron Institute, Private Bag 2, Nelson, 7010, New Zealand
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Barbosa M, Lefler FW, Berthold DE, Gettys LA, Leary JK, Laughinghouse HD. Macrophyte coverage drives microbial community structure and interactions in a shallow sub-tropical lake. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 923:171414. [PMID: 38442760 DOI: 10.1016/j.scitotenv.2024.171414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 02/27/2024] [Accepted: 02/29/2024] [Indexed: 03/07/2024]
Abstract
Shallow lakes are typically dominated by macrophytes, which have important functional roles regulating trophic conditions and creating biological habitat. Macrophytes have been shown to strongly influence water chemistry and shape microbial communities in shallow lakes. In Florida, many large, shallow lakes are dominated by alien invasive, submersed macrophytes, such as hydrilla (Hydrilla verticillata [L.F.] Royle) and are intensively managed to reduce infestations and contain the spread of these alien invasive macrophytes. In this study, we investigated the effects of large (40 ha) herbicidal and mechanical control treatments on a large lake located in Central Florida that resulted in the reduction of Hydrilla and concomitant changes in water chemistry and microbial communities (both bacteria and protists [microbial eukaryotes]). We observed a considerable decrease in macrophyte coverage associated with plant control treatments as well as a temporal change in macrophyte coverage in Lake Tohopekaliga. We found that changes in macrophyte coverage, regardless of treatment type, significantly affected the water chemistry of the lake, resulting in a sharp increase of chlorophyll a concentration as well as an increase in turbidity with the decrease of macrophyte coverage. Moreover, the decline in macrophytes led to decreases in microbial community diversity with over-representation of phototrophic functional groups. Specifically, we observed an increase in cyanobacteria with the decrease in macrophyte coverage. Our study highlights the advantages and disadvantages of macrophyte control. Although there was an initial decrease in macrophyte coverage associated with the chemical and mechanical control of aquatic plants, after a few months, we found a considerable increase in coverage. In addition, the increase of cyanobacterial relative abundance demonstrates the possible consequences of aquatic plant control such as cyanobacterial blooms if there is a continued decline of macrophytes.
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Affiliation(s)
- Maximiliano Barbosa
- Agronomy Department, Ft. Lauderdale Research and Education Center, University of Florida, IFAS, 3205 College Avenue, Davie, FL 33314, USA
| | - Forrest W Lefler
- Agronomy Department, Ft. Lauderdale Research and Education Center, University of Florida, IFAS, 3205 College Avenue, Davie, FL 33314, USA
| | - David E Berthold
- Agronomy Department, Ft. Lauderdale Research and Education Center, University of Florida, IFAS, 3205 College Avenue, Davie, FL 33314, USA
| | - Lyn A Gettys
- Agronomy Department, Ft. Lauderdale Research and Education Center, University of Florida, IFAS, 3205 College Avenue, Davie, FL 33314, USA
| | - James K Leary
- UF/IFAS Center of Aquatic and Invasive Plants, University of Florida, 7922 NW 71 St, Gainesville, FL 32653, USA
| | - H Dail Laughinghouse
- Agronomy Department, Ft. Lauderdale Research and Education Center, University of Florida, IFAS, 3205 College Avenue, Davie, FL 33314, USA.
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3
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Lefler FW, Barbosa M, Berthold DE, Roten R, Bishop WM, Laughinghouse HD. Microbial Community Response to Granular Peroxide-Based Algaecide Treatment of a Cyanobacterial Harmful Algal Bloom in Lake Okeechobee, Florida (USA). Toxins (Basel) 2024; 16:206. [PMID: 38787058 PMCID: PMC11125911 DOI: 10.3390/toxins16050206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/19/2024] [Accepted: 04/20/2024] [Indexed: 05/25/2024] Open
Abstract
Cyanobacterial harmful algal blooms (cyanoHABs) occur in fresh water globally. These can degrade water quality and produce toxins, resulting in ecological and economic damages. Thus, short-term management methods (i.e., algaecides) are necessary to rapidly mitigate the negative impacts of cyanoHABs. In this study, we assess the efficacy of a hydrogen peroxide-based algaecide (PAK® 27) on a Microcystis dominated bloom which occurred within the Pahokee Marina on Lake Okeechobee, Florida, USA. We observed a significant reduction in chlorophyll a (96.81%), phycocyanin (93.17%), and Microcystis cell counts (99.92%), and a substantial reduction in microcystins (86.7%) 48 h after treatment (HAT). Additionally, there was a significant shift in bacterial community structure 48 HAT, which coincided with an increase in the relative abundance of photosynthetic protists. These results indicate that hydrogen peroxide-based algaecides are an effective treatment method for cyanoHAB control and highlight their effects on non-target microorganisms (i.e., bacteria and protists).
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Affiliation(s)
- Forrest W. Lefler
- Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL 33314, USA; (F.W.L.); (M.B.); (D.E.B.)
| | - Maximiliano Barbosa
- Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL 33314, USA; (F.W.L.); (M.B.); (D.E.B.)
| | - David E. Berthold
- Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL 33314, USA; (F.W.L.); (M.B.); (D.E.B.)
| | - Rory Roten
- SePRO Research and Technology Campus, 16013 Watson Seed Farm Road, Whitakers, NC 27891, USA; (R.R.); (W.M.B.)
| | - West M. Bishop
- SePRO Research and Technology Campus, 16013 Watson Seed Farm Road, Whitakers, NC 27891, USA; (R.R.); (W.M.B.)
| | - H. Dail Laughinghouse
- Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL 33314, USA; (F.W.L.); (M.B.); (D.E.B.)
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Bishop SL, Solonenka JT, Giebelhaus RT, Bakker DTR, Li ITS, Murch SJ. Microbial Diversity Impacts Non-Protein Amino Acid Production in Cyanobacterial Bloom Cultures Collected from Lake Winnipeg. Toxins (Basel) 2024; 16:169. [PMID: 38668594 PMCID: PMC11053616 DOI: 10.3390/toxins16040169] [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: 02/14/2024] [Revised: 03/10/2024] [Accepted: 03/20/2024] [Indexed: 04/29/2024] Open
Abstract
Lake Winnipeg in Manitoba, Canada is heavily impacted by harmful algal blooms that contain non-protein amino acids (NPAAs) produced by cyanobacteria: N-(2-aminoethyl)glycine (AEG), β-aminomethyl-L-alanine (BAMA), β-N-methylamino-L-alanine (BMAA), and 2,4-diaminobutyric acid (DAB). Our objective was to investigate the impact of microbial diversity on NPAA production by cyanobacteria using semi-purified crude cyanobacterial cultures established from field samples collected by the Lake Winnipeg Research Consortium between 2016 and 2021. NPAAs were detected and quantified by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) using validated analytical methods, while Shannon and Simpson alpha diversity scores were determined from 16S rRNA metagenomic sequences. Alpha diversity in isolate cultures was significantly decreased compared to crude cyanobacterial cultures (p < 0.001), indicating successful semi-purification. BMAA and AEG concentrations were higher in crude compared to isolate cultures (p < 0.0001), and AEG concentrations were correlated to the alpha diversity in cultures (r = 0.554; p < 0.0001). BAMA concentrations were increased in isolate cultures (p < 0.05), while DAB concentrations were similar in crude and isolate cultures. These results demonstrate that microbial community complexity impacts NPAA production by cyanobacteria and related organisms.
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Affiliation(s)
- Stephanie L. Bishop
- Department of Chemistry, University of British Columbia, Syilx Okanagan Nation Territory, Kelowna, BC V1V 1V7, Canada; (J.T.S.); (R.T.G.); (D.T.R.B.); (I.T.S.L.); (S.J.M.)
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Julia T. Solonenka
- Department of Chemistry, University of British Columbia, Syilx Okanagan Nation Territory, Kelowna, BC V1V 1V7, Canada; (J.T.S.); (R.T.G.); (D.T.R.B.); (I.T.S.L.); (S.J.M.)
| | - Ryland T. Giebelhaus
- Department of Chemistry, University of British Columbia, Syilx Okanagan Nation Territory, Kelowna, BC V1V 1V7, Canada; (J.T.S.); (R.T.G.); (D.T.R.B.); (I.T.S.L.); (S.J.M.)
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2N4, Canada
- The Metabolomics Innovation Centre, Edmonton, AB T6G 2N4, Canada
| | - David T. R. Bakker
- Department of Chemistry, University of British Columbia, Syilx Okanagan Nation Territory, Kelowna, BC V1V 1V7, Canada; (J.T.S.); (R.T.G.); (D.T.R.B.); (I.T.S.L.); (S.J.M.)
| | - Isaac T. S. Li
- Department of Chemistry, University of British Columbia, Syilx Okanagan Nation Territory, Kelowna, BC V1V 1V7, Canada; (J.T.S.); (R.T.G.); (D.T.R.B.); (I.T.S.L.); (S.J.M.)
| | - Susan J. Murch
- Department of Chemistry, University of British Columbia, Syilx Okanagan Nation Territory, Kelowna, BC V1V 1V7, Canada; (J.T.S.); (R.T.G.); (D.T.R.B.); (I.T.S.L.); (S.J.M.)
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5
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Cameron ES, Krishna A, Emelko MB, Müller KM. Sporadic diurnal fluctuations of cyanobacterial populations in oligotrophic temperate systems can prevent accurate characterization of change and risk in aquatic systems. WATER RESEARCH 2024; 252:121199. [PMID: 38330712 DOI: 10.1016/j.watres.2024.121199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 01/12/2024] [Accepted: 01/23/2024] [Indexed: 02/10/2024]
Abstract
Cyanobacteria increasingly threaten recreational water use and drinking water resources globally. They require dynamic monitoring to account for variability in their distribution arising from diel cycles associated with oscillatory vertical migration. While this has been discussed in marine and eutrophic freshwater contexts, reports of diurnal vertical migration of cyanobacteria in oligotrophic freshwater lakes are scant. Typical monitoring protocols do not reflect these dynamics and frequently focus only on surface water sampling approaches, and either ignore sampling time or recommend large midday timeframes (e.g., 10AM-3PM), thereby preventing accurate characterization of cyanobacterial community dynamics. To evaluate the impact of diurnal migrations and water column stratification on cyanobacterial abundance and composition, communities were characterized in a shallow well-mixed lake interconnected to a thermally stratified lake in the Turkey Lakes Watershed (Ontario, Canada) using amplicon sequencing of the 16S rRNA gene across a multi-time point sampling series in 2018 and 2022. This work showed that cyanobacteria are present in oligotrophic lakes and their community structure varies (i) diurnally, (ii) across the depth of the water column, (iii) interannually within the same lake and (iv) between different lakes that are closely interconnected within the same watershed. It underscored the need for integrating multi-timepoint, multi-depth discrete sampling guidance into lake and reservoir monitoring programs to describe cyanobacteria community dynamics and signal change to inform risk management associated with the potential for cyanotoxin production. Ignoring variability in cyanobacterial community dynamics (such as that reported herein) and reducing sample numbers can lead to a false sense of security and missed opportunities to identify and mitigate changes in trophic status and associated risks such as toxin or taste and odor production, especially in sensitive, oligotrophic systems.
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Affiliation(s)
- Ellen S Cameron
- Department of Biology, University of Waterloo, 200 University Ave. W, Waterloo, Ontario, N2L 3G1, Canada
| | - Anjali Krishna
- Department of Biology, University of Waterloo, 200 University Ave. W, Waterloo, Ontario, N2L 3G1, Canada
| | - Monica B Emelko
- Department of Civil & Environmental Engineering, University of Waterloo, 200 University Ave. W, Waterloo, Ontario, N2L 3G1, Canada
| | - Kirsten M Müller
- Department of Biology, University of Waterloo, 200 University Ave. W, Waterloo, Ontario, N2L 3G1, Canada.
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6
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Fray D, McGovern CA, Casamatta DA, Biddanda BA, Hamsher SE. Metabarcoding reveals unique microbial mat communities and evidence of biogeographic influence in low-oxygen, high-sulfur sinkholes and springs. Ecol Evol 2024; 14:e11162. [PMID: 38529029 PMCID: PMC10961586 DOI: 10.1002/ece3.11162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 02/16/2024] [Accepted: 03/05/2024] [Indexed: 03/27/2024] Open
Abstract
High-sulfur, low-oxygen environments formed by underwater sinkholes and springs create unique habitats populated by microbial mat communities. To explore the diversity and biogeography of these mats, samples were collected from three sites in Alpena, Michigan, one site in Monroe, Michigan, and one site in Palm Coast, Florida. Our study investigated previously undescribed eukaryotic diversity in these habitats and further explored their bacterial communities. Mat samples and water parameters were collected from sulfur spring sites during the spring, summer, and fall of 2022. Cyanobacteria and diatoms were cultured from mat subsamples to create a culture-based DNA reference library. Remaining mat samples were used for metabarcoding of the 16S and rbcL regions to explore bacterial and diatom diversity, respectively. Analyses of water chemistry, alpha diversity, and beta diversity articulated a range of high-sulfur, low-oxygen habitats, each with distinct microbial communities. Conductivity, pH, dissolved oxygen, temperature, sulfate, and chloride had significant influences on community composition but did not describe the differences between communities well. Chloride concentration had the strongest correlation with microbial community structure. Mantel tests revealed that biogeography contributed to differences between communities as well. Our results provide novel information on microbial mat composition and present evidence that both local conditions and biogeography influence these unique communities.
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Affiliation(s)
- Davis Fray
- Annis Water Resources InstituteGrand Valley State UniversityMuskegonMichiganUSA
| | | | - Dale A. Casamatta
- Department of BiologyUniversity of North FloridaJacksonvilleFloridaUSA
| | - Bopaiah A. Biddanda
- Annis Water Resources InstituteGrand Valley State UniversityMuskegonMichiganUSA
| | - Sarah E. Hamsher
- Annis Water Resources InstituteGrand Valley State UniversityMuskegonMichiganUSA
- Department of BiologyGrand Valley State UniversityAllendaleMichiganUSA
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7
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Wheeler C, Pearman JK, Howarth JD, Vandergoes MJ, Holt K, Trewick SA, Li X, Thompson L, Thomson-Laing G, Picard M, Moy C, Mckay NP, Moody A, Shepherd C, van den Bos V, Steiner K, Wood SA. A paleoecological investigation of recent cyanobacterial blooms and their drivers in two contrasting lakes. HARMFUL ALGAE 2024; 131:102563. [PMID: 38212085 DOI: 10.1016/j.hal.2023.102563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/17/2023] [Accepted: 12/18/2023] [Indexed: 01/13/2024]
Abstract
Cyanobacterial blooms are one of the most significant threats to global water security and freshwater biodiversity. Interactions among multiple stressors, including habitat degradation, species invasions, increased nutrient runoff, and climate change, are key drivers. However, assessing the role of anthropogenic activity on the onset of cyanobacterial blooms and exploring response variation amongst lakes of varying size and depth is usually limited by lack of historical records. In the present study we applied molecular, paleolimnological (trace metal, Itrax-µ-XRF and hyperspectral scanning, chronology), paleobotanical (pollen) and historical data to reconstruct cyanobacterial abundance and community composition and anthropogenic impacts in two dune lakes over a period of up to 1200 years. Metabarcoding and droplet digital PCR results showed very low levels of picocyanobacteria present in the lakes prior to about CE 1854 (1839-1870 CE) in the smaller shallow Lake Alice and CE 1970 (1963-1875 CE) in the larger deeper Lake Wiritoa. Hereafter bloom-forming cyanobacteria were detected and increased notably in abundance post CE 1984 (1982-1985 CE) in Lake Alice and CE 1997 (1990-2007 CE) in Lake Wiritoa. Currently, the magnitude of blooms is more pronounced in Lake Wiritoa, potentially attributable to hypoxia-induced release of phosphorus from sediment, introducing an additional source of nutrients. Generalized linear modelling was used to investigate the contribution of nutrients (proxy = bacterial functions), temperature, redox conditions (Mn:Fe), and erosion (Ti:Inc) in driving the abundance of cyanobacteria (ddPCR). In Lake Alice nutrients and erosion had a statistically significant effect, while in Lake Wiritoa nutrients and redox conditions were significant.
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Affiliation(s)
- Caitlin Wheeler
- Massey University, Tennent Drive, Palmerston North 4410, Aotearoa, New Zealand
| | - John K Pearman
- Cawthron Institute, Private Bag 2 Aotearoa, Nelson 7042, New Zealand
| | - Jamie D Howarth
- School of Geography, Environment and Earth Sciences, Victoria University of Wellington, PO Box 600 Aotearoa, Wellington 6012, New Zealand
| | | | - Katherine Holt
- Massey University, Tennent Drive, Palmerston North 4410, Aotearoa, New Zealand
| | - Steven A Trewick
- Massey University, Tennent Drive, Palmerston North 4410, Aotearoa, New Zealand
| | - Xun Li
- School of Geography, Environment and Earth Sciences, Victoria University of Wellington, PO Box 600 Aotearoa, Wellington 6012, New Zealand
| | - Lucy Thompson
- Cawthron Institute, Private Bag 2 Aotearoa, Nelson 7042, New Zealand
| | | | - Mailys Picard
- Cawthron Institute, Private Bag 2 Aotearoa, Nelson 7042, New Zealand; Department of Ecology and Environmental Science, Umeå Universitet, Linnaeus väg 4-6, Umeå 907 36, Sweden
| | - Chris Moy
- Department of Geology, University of Otago, 360 Leith Street Aotearoa, North Dunedin, Dunedin 9054, New Zealand
| | - Nicholas P Mckay
- School of Earth and Sustainability, Northern Arizona University, Flagstaf, AZ, United States
| | - Adelaine Moody
- School of Geography, Environment and Earth Sciences, Victoria University of Wellington, PO Box 600 Aotearoa, Wellington 6012, New Zealand
| | - Claire Shepherd
- GNS Science, 1 Fairway Drive Aotearoa, Avalon, Lower Hutt 5011, New Zealand
| | | | - Konstanze Steiner
- Cawthron Institute, Private Bag 2 Aotearoa, Nelson 7042, New Zealand
| | - Susanna A Wood
- Massey University, Tennent Drive, Palmerston North 4410, Aotearoa, New Zealand.
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Lefler FW, Barbosa M, Zimba PV, Smyth AR, Berthold DE, Laughinghouse HD. Spatiotemporal diversity and community structure of cyanobacteria and associated bacteria in the large shallow subtropical Lake Okeechobee (Florida, United States). Front Microbiol 2023; 14:1219261. [PMID: 37711696 PMCID: PMC10499181 DOI: 10.3389/fmicb.2023.1219261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 08/14/2023] [Indexed: 09/16/2023] Open
Abstract
Lake Okeechobee is a large eutrophic, shallow, subtropical lake in south Florida, United States. Due to decades of nutrient loading and phosphorus rich sediments, the lake is eutrophic and frequently experiences cyanobacterial harmful algal blooms (cyanoHABs). In the past, surveys of the phytoplankton community structure in the lake have been conducted by morphological studies, whereas molecular based studies have been seldom employed. With increased frequency of cyanoHABs in Lake Okeechobee (e.g., 2016 and 2018 Microcystis-dominated blooms), it is imperative to determine the diversity of cyanobacterial taxa that exist within the lake and the limnological parameters that drive bloom-forming genera. A spatiotemporal study of the lake was conducted over the course of 1 year to characterize the (cyano)bacterial community structure, using 16S rRNA metabarcoding, with coincident collection of limnological parameters (e.g., nutrients, water temperature, major ions), and cyanotoxins. The objectives of this study were to elucidate spatiotemporal trends of community structure, identify drivers of community structure, and examine cyanobacteria-bacterial relationships within the lake. Results indicated that cyanobacterial communities within the lake were significantly different between the wet and dry season, but not between periods of nitrogen limitation and co-nutrient limitation. Throughout the year, the lake was primarily dominated by the picocyanobacterium Cyanobium. The bloom-forming genera Cuspidothrix, Dolichospermum, Microcystis, and Raphidiopsis were highly abundant throughout the lake and had disparate nutrient requirements and niches within the lake. Anatoxin-a, microcystins, and nodularins were detected throughout the lake across both seasons. There were no correlated (cyano)bacteria shared between the common bloom-forming cyanobacteria Dolichospermum, Microcystis, and Raphidiopsis. This study is the first of its kind to use molecular based methods to assess the cyanobacterial community structure within the lake. These data greatly improve our understanding of the cyanobacterial community structure within the lake and the physiochemical parameters which may drive the bloom-forming taxa within Lake Okeechobee.
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Affiliation(s)
- Forrest W. Lefler
- Agronomy Department, Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL, United States
| | - Maximiliano Barbosa
- Agronomy Department, Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL, United States
| | - Paul V. Zimba
- Rice Rivers Center, Virginia Commonwealth University, Charles City, VA, United States
| | - Ashley R. Smyth
- Soil, Water and Ecosystem Sciences Department, Tropical Research and Education Center, University of Florida—IFAS, Homestead, FL, United States
| | - David E. Berthold
- Agronomy Department, Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL, United States
| | - H. Dail Laughinghouse
- Agronomy Department, Fort Lauderdale Research and Education Center, University of Florida—IFAS, Davie, FL, United States
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9
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Gabyshev VA, Sidelev SI, Chernova EN, Vilnet AA, Davydov DA, Barinova S, Gabysheva OI, Zhakovskaya ZA, Voronov IV. Year-Round Presence of Microcystins and Toxin-Producing Microcystis in the Water Column and Ice Cover of a Eutrophic Lake Located in the Continuous Permafrost Zone (Yakutia, Russia). Toxins (Basel) 2023; 15:467. [PMID: 37505736 PMCID: PMC10467126 DOI: 10.3390/toxins15070467] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 07/11/2023] [Accepted: 07/18/2023] [Indexed: 07/29/2023] Open
Abstract
This study aimed to test the hypothesis of the year-round presence of toxigenic Microcystis and cyanotoxins in the water and ice of the shallow eutrophic Lake Ytyk-Kyuyol located in the continuous permafrost zone. Three independent approaches-mass-spectrometry, molecular methods and light microscopy-were applied in the study. The cyanobacterial biomass ranged from 1.0 × 10-4 to 4.8 mg L-1. Microcystis flos-aquae and M. aeruginosa were the dominant morphospecies in plankton throughout the observation. In environmental DNA, the presence of M. aeruginosa was supported and mcy gene regions responsible for microcystin biosynthesis were detected through a BLAST (Basic Local Alignment Search Tool) search and phylogenetic estimation based on newly obtained 16S rRNA, 16S-23S ITS rRNA, mcyA and mcyE nucleotide sequences. The intracellular microcystin concentration ranged from <0.1 to 803 ng L-1, and the microcystin quota in the Microcystis biomass was extremely low. For the first time, it was shown that Microcystis cells containing mcy genes and microcystins presented permanently in the water column, both during the ice-free period and under ice, as well as inside thick ice covers within 7 months of severe winter. We hypothesized that minor pelagic and ice populations of Microcystis could participate in increasing cell density in the spring. However, further studies are needed to confirm the viability of the overwintering Microcystis colonies in the water and inside the ice of Lake Ytyk-Kyuyol.
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Affiliation(s)
- Viktor A. Gabyshev
- Institute for Biological Problems of Cryolithozone, Siberian Branch, Russian Academy of Sciences, Yakutsk 677980, Russia; (V.A.G.); (O.I.G.); (I.V.V.)
| | - Sergey I. Sidelev
- Faculty of Biology and Ecology, Yaroslavl State University, Yaroslavl 150057, Russia;
- Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Yaroslavl 152742, Russia
| | - Ekaterina N. Chernova
- Scientific Research Centre for Ecological Safety, St. Petersburg Federal Research Center, Russian Academy of Sciences, St. Petersburg 197110, Russia; (E.N.C.); (Z.A.Z.)
| | - Anna A. Vilnet
- Polar-Alpine Botanic Garden-Institute—Subdivision of the Federal Research Centre “Kola Science Centre”, Apatity 184209, Russia; (A.A.V.); (D.A.D.)
| | - Denis A. Davydov
- Polar-Alpine Botanic Garden-Institute—Subdivision of the Federal Research Centre “Kola Science Centre”, Apatity 184209, Russia; (A.A.V.); (D.A.D.)
- Institute of North Industrial Ecology Problems—Subdivision of the Federal Research Center “Kola Science Center”, Apatity 184209, Russia
| | - Sophia Barinova
- Institute of Evolution, University of Haifa, Mount Carmel, 199 Abba Khoushi Ave., Haifa 3498838, Israel
| | - Olga I. Gabysheva
- Institute for Biological Problems of Cryolithozone, Siberian Branch, Russian Academy of Sciences, Yakutsk 677980, Russia; (V.A.G.); (O.I.G.); (I.V.V.)
| | - Zoya A. Zhakovskaya
- Scientific Research Centre for Ecological Safety, St. Petersburg Federal Research Center, Russian Academy of Sciences, St. Petersburg 197110, Russia; (E.N.C.); (Z.A.Z.)
| | - Ivan V. Voronov
- Institute for Biological Problems of Cryolithozone, Siberian Branch, Russian Academy of Sciences, Yakutsk 677980, Russia; (V.A.G.); (O.I.G.); (I.V.V.)
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