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Liu J, Dong Y, Lin H. Effects of microcystin-LR on purification efficiency of simulating drinking water source by Hydrocharis dubia (Bl.) backer. Toxicon 2024; 241:107654. [PMID: 38368956 DOI: 10.1016/j.toxicon.2024.107654] [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: 01/02/2024] [Revised: 02/10/2024] [Accepted: 02/16/2024] [Indexed: 02/20/2024]
Abstract
The safety of drinking water source directly affects human health. Microcystin-LR (MC-LR), a toxic and common pollutant in drinking water source, is released by algae and can impede the in-situ remediation effect of aquatic plant. Finding out the effect mechanism of MC-LR on the purification of drinking water by aquatic plant is the key to its application. This study aims to explore the performance and mechanism of MC-LR on drinking water source purification by Hydrocharis dubia (Bl.) backer. The optimum removal efficiency of NH4+-N, TP and COD were 90.7%, 93.2% and 77.3% at MC-LR concentration of 0.5 μg L-1, respectively. With the increase of MC-LR concentration, the pollutants removal rate was obviously inhibited causing by concentration-dependent. Furthermore, the growth and development of the Hydrocharis dubia (Bl.) backer roots were significantly promoted at the concentration of 0.1 μg L-1. The length, tips, surface area, and average diameter of the root increased by 71.3%, 271.4%, 265.5%, and 113.0%, respectively. Chlorophyll contents under low-concentration MC-LR show a 14.5%-15.7% promoting effect compared with the control group. The activities of POD and CAT were also stimulated with the MC-LR increasing (<1.0 μg L-1). Notably, the MDA contents increased with increasing MC-LR concentration (p < 0.01). This study indicates the effect mechanism of MC-LR on Hydrocharis dubia (Bl.) backer purification performance relies on the increased growth and enzyme activity of Hydrocharis dubia (Bl.) backer.
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Affiliation(s)
- Junfei Liu
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants, Beijing, 100083, China; Shunde Innovation School, University of Science and Technology Beijing, Shunde, 528399, China.
| | - Yingbo Dong
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants, Beijing, 100083, China
| | - Hai Lin
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants, Beijing, 100083, China.
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2
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Miles CO, Strand DA, Rusch JC, Ballot A, Haande S, Løvberg KLE, Vrålstad T, Samdal IA. Microcystin profiles in European noble crayfish Astacus astacus and water in Lake Steinsfjorden, Norway. ENVIRONMENTAL RESEARCH 2024; 242:117623. [PMID: 37956753 DOI: 10.1016/j.envres.2023.117623] [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: 08/24/2023] [Revised: 10/18/2023] [Accepted: 11/07/2023] [Indexed: 11/15/2023]
Abstract
Lake Steinsfjorden, an important noble crayfish (Astacus astacus) habitat, is often affected by blooms of Planktothrix spp. that produce microcystins (MCs). A poor correlation between MCs by ELISA in the water and in crayfish tissue in a study in 2015 prompted further investigation by LC-HRMS. LC-HRMS analyses of filters from water samples and on selected crayfish tissue extracts from the 2015 study revealed the presence of known and previously unreported MCs. Crayfish samples from May and June 2015 were dominated by MCs from the Planktothrix bloom, whereas in September novel MCs that appeared to be metabolites of MC-LR were dominant, even though neither these nor MC-LR were detected in the water in 2015. A water sample from October 2016 also showed MCs typical of Planktothrix (i.e., [d-Asp3]- and [d-Asp3,Dhb7]MC-RR and -LR), but low levels of MC-RR and MC-LR were detected in the lake water for the first time. In late summer and autumn, the MC profiles of crayfish were dominated by the homonorvaline (Hnv) variant MC-LHnv, a putative metabolite of MC-LR. Taken together, ELISA, LC-HRMS and previous PCR analyses showed that although Planktothrix was part of the crayfish diet, it was not the sole source of MCs in the crayfish. Possibly, crayfish in Lake Steinsfjorden may be ingesting MCs from benthic cyanobacteria or from contaminated prey. Therefore, information on the cyanobacterial or MC content in the water column cannot safely be used to make predictions about MC concentrations in the crayfish in Lake Steinsfjorden. Interestingly, the results also show that targeted LC-MS analysis of the crayfish would at times have underestimated their MC content by nearly an order of magnitude, even if all previously reported MC variants had been included in the analysis.
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Affiliation(s)
- Christopher O Miles
- Norwegian Veterinary Institute, Elizabeth Stephansens vei 1, 1433, Ås, Norway; National Research Council Canada, Halifax, Nova Scotia, B3H 3Z1, Canada
| | - David A Strand
- Norwegian Veterinary Institute, Elizabeth Stephansens vei 1, 1433, Ås, Norway
| | - Johannes C Rusch
- Norwegian Veterinary Institute, Elizabeth Stephansens vei 1, 1433, Ås, Norway
| | - Andreas Ballot
- Norwegian Institute for Water Research, Økernveien 94, 0579, Oslo, Norway
| | - Sigrid Haande
- Norwegian Institute for Water Research, Økernveien 94, 0579, Oslo, Norway
| | - Kjersti L E Løvberg
- Norwegian Veterinary Institute, Elizabeth Stephansens vei 1, 1433, Ås, Norway
| | - Trude Vrålstad
- Norwegian Veterinary Institute, Elizabeth Stephansens vei 1, 1433, Ås, Norway
| | - Ingunn A Samdal
- Norwegian Veterinary Institute, Elizabeth Stephansens vei 1, 1433, Ås, Norway.
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Premathilaka SH, Westrick JA, Isailovic D. Identification of Serine-Containing Microcystins by UHPLC-MS/MS Using Thiol and Sulfoxide Derivatizations and Detection of Novel Neutral Losses. Anal Chem 2024; 96:775-786. [PMID: 38170221 DOI: 10.1021/acs.analchem.3c04047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Microcystins (MCs) are hepatotoxic cyclic heptapeptides produced by cyanobacteria, and their structural diversity has led to the discovery of more than 300 congeners to date. However, with known amino acid combinations, many more MC congeners are theoretically possible, suggesting many remain unidentified. Herein, two novel serine (Ser)-containing MCs were putatively identified in a Lake Erie cyanobacterial harmful algal bloom (cyanoHAB), using high-resolution UHPLC-MS as well as thiol and sulfoxide derivatization procedures. These MCs contain an α,β-unsaturated carbonyl on methyl dehydroalanine (Mdha) residue that undergoes Michael addition to produce a thiol-derivatized MC. Derivatization reactions using various thiolation reagents were followed by MS/MS, and two Python codes were used for data analysis and structural elucidation of MCs. Two novel MCs containing Ser at position 1 (i.e., next to Mdha) were putatively identified as [Ser1]MC-RR and [Ser1]MC-YR. Using thiol- and sulfoxide-modified [Ser1]MCs, identifications were confirmed by the observation of specific neutral losses of the oxidized thiols or sulfoxides in CID-MS/MS spectra in both positive and negative electrospray ionization (ESI) modes. These novel neutral losses are unique for MCs with Mdha and an adjacent Ser residue. Data suggest that a gas-phase reaction occurs between oxygen from adjacent Ser residue and sulfur of the Mdha-bonded thiol or sulfoxide, which leads to the formation and detection of stable cyclic MC ions in MS/MS spectra at m/z values corresponding to the loss of oxidized thiols or oxidized sulfoxides from Ser1-containing MCs.
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Affiliation(s)
- Sanduni H Premathilaka
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, Ohio 43606, United States
| | - Judy A Westrick
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Dragan Isailovic
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, Ohio 43606, United States
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4
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Bouteiller P, Lance E, Guérin T, Biré R. Analysis of Total-Forms of Cyanotoxins Microcystins in Biological Matrices: A Methodological Review. Toxins (Basel) 2022; 14:toxins14080550. [PMID: 36006212 PMCID: PMC9416067 DOI: 10.3390/toxins14080550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/22/2022] [Accepted: 08/09/2022] [Indexed: 11/16/2022] Open
Abstract
Microcystins (MCs) are cyclic heptapeptidic toxins produced by many cyanobacteria. Microcystins can be accumulated in various matrices in two forms: a free cellular fraction and a covalently protein-bound form. To detect and quantify the concentration of microcystins, a panel of techniques on various matrices (water, sediments, and animal tissues) is available. The analysis of MCs can concern the free or the total (free plus covalently bound) fractions. Free-form analyses of MCs are the most common and easiest to detect, whereas total-form analyses are much less frequent and more complex to achieve. The objective of this review is to summarize the different methods of extraction and analysis that have been developed for total forms. Four extraction methods were identified: MMPB (2-methyl-3-methoxy-4-phenylbutyric acid) method, deconjugation at basic pH, ozonolysis, and laser irradiation desorption. The study of the bibliography on the methods of extraction and analysis of the total forms of MCs showed that the reference method for the subject remains the MMPB method even if alternative methods and, in particular, deconjugation at basic pH, showed results encouraging the continuation of the methodological development on different matrices and on naturally-contaminated samples.
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Affiliation(s)
- Pierre Bouteiller
- Université de Reims Champagne-Ardenne, UMR-I 02 INERIS-URCA-ULH SEBIO, Unité Stress Environnementaux et BIOsurveillance des Milieux Aquatiques (SEBIO), BP 1039, CEDEX 2, F-51687 Reims, France
- Laboratory for Food Safety, ANSES, F-94701 Maisons-Alfort, France
| | - Emilie Lance
- Université de Reims Champagne-Ardenne, UMR-I 02 INERIS-URCA-ULH SEBIO, Unité Stress Environnementaux et BIOsurveillance des Milieux Aquatiques (SEBIO), BP 1039, CEDEX 2, F-51687 Reims, France
- UMR MNHN/CNRS MCAM, Muséum National d’Histoire Naturelle, F-75005 Paris, France
- Correspondence:
| | - Thierry Guérin
- Strategy and Programs Department, ANSES, F-94701 Maisons-Alfort, France
| | - Ronel Biré
- Laboratory for Food Safety, ANSES, F-94701 Maisons-Alfort, France
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Johnson RE, van der Zalm JM, Chen A, Bell IJ, Van Raay TJ, Al-Abdul-Wahid MS, Manderville RA. Unraveling the Chemosensing Mechanism by the 7-(Diethylamino)coumarin-hemicyanine Hybrid: A Ratiometric Fluorescent Probe for Hydrogen Peroxide. Anal Chem 2022; 94:11047-11054. [PMID: 35894588 DOI: 10.1021/acs.analchem.2c01852] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The hemicyanine hybrid containing the 7-(diethylamino)coumarin (ACou) donor attached to the cationic indolenium (Ind) acceptor through a vinyl linkage (ACou-Ind) represents a classic ratiometric fluorescent probe for detecting nucleophilic analytes, such as cyanide and reactive sulfur species (RSS), through addition reactions that disrupt dye conjugation to turn off red internal charge transfer (ICT) fluorescence and turn on blue coumarin emission. The chemosensing mechanism for RSS detection by ACou-Ind suggested in the literature has now been revised. Our studies demonstrate that thiolates react with ACou-Ind through conjugate addition to afford C4-SR adducts that lack coumarin fluorescence due to photoinduced electron transfer quenching by the electron-rich enamine intermediate. Thus, ACou-Ind serves as a turn-off probe through loss of red ICT fluorescence upon RSS addition. The literature also suggests that blue coumarin emission of thiolate adducts is enhanced in the presence of reactive oxygen species (ROS) due to ROS-mediated cellular changes. Our studies predict that such a scenario is unlikely and that thiolate adducts undergo oxidative deconjugation in the presence of H2O2, the pervasive ROS. Under basic conditions, H2O2 also reacts directly with ACou-Ind to generate intense coumarin fluorescence through an epoxidation process. The relevance of our chemosensing mechanism for ACou-Ind was assessed within live zebrafish, and implications for the utility of ACou-Ind for unraveling the interplay between RSS and ROS are discussed.
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Affiliation(s)
- Ryan E Johnson
- Departments of Chemistry and Toxicology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Joshua M van der Zalm
- Departments of Chemistry and Toxicology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Aicheng Chen
- Departments of Chemistry and Toxicology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Ian J Bell
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Terence J Van Raay
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | | | - Richard A Manderville
- Departments of Chemistry and Toxicology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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Uhlig S, Ivanova L, Miles CO. Oxidative Release of Thiol-Conjugated Forms of the Mycotoxin 4-Deoxynivalenol. Chem Res Toxicol 2020; 33:515-521. [PMID: 31867960 DOI: 10.1021/acs.chemrestox.9b00385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Deoxynivalenol (DON) is a trichothecene mycotoxin that is produced by several species of Fusarium, which may infect grain crops. DON, as well as other type-B trichothecenes, contain an α,β-unsaturated carbonyl group that may react with sulfhydryl groups in, for example, amino acids and peptides. Such conjugates have been shown to occur in plants. Nucleophilic addition of thiols to the conjugated double bond in DON afforded several isomeric reaction products, and the thermodynamically favored isomers of DON-10-cysteine and DON-10-glutathione have been prepared and characterized previously. This study reports the preparation and characterization of the kinetically favored DON-10-cysteine isomer. We subsequently studied and compared the rate of the deconjugation reaction of the two DON-10-cysteine isomers and the thermodynamically favored DON-10-glutathione adduct. The deconjugation rate of the thermodynamically favored thiol conjugates was slow with half-lives of weeks even at pH 10.7, while the kinetically favored DON-10-cysteine isomer deconjugated within a few hours, affording free DON. We adapted a simple and rapid oxidation protocol in which the sulfide linkage was oxidized to a sulfoxide or sulfone that, when treated with the base, rapidly eliminated the adducted thiol as its sulfenate or sulfinate to afford free DON. The deconjugation reactions of the sulfoxides and sulfones of thermodynamically favored DON-10-thiols were complete within hours or minutes at pH 10.7, respectively. The increase in deconjugation rates for the kinetically favored DON-10-cysteine were less dramatic. Oxidation of sulfides to sulfoxides is known to occur in vivo, and thus, our data show that thiol-conjugated DON might become bioavailable via sulfide oxidation followed by elimination to regenerate DON. The oxidation-elimination approach could also be useful for the indirect quantification of DON-10-thiol conjugates in plant and animal tissues.
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Affiliation(s)
- Silvio Uhlig
- Toxinology Research Group , Norwegian Veterinary Institute , Ullevålsveien 68 , 0454 Oslo , Norway
| | - Lada Ivanova
- Toxinology Research Group , Norwegian Veterinary Institute , Ullevålsveien 68 , 0454 Oslo , Norway
| | - Christopher O Miles
- Biotoxin Metrology , National Research Council , 1411 Oxford Street , Halifax , NS B3H 3Z1 , Canada
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Bouaïcha N, Miles CO, Beach DG, Labidi Z, Djabri A, Benayache NY, Nguyen-Quang T. Structural Diversity, Characterization and Toxicology of Microcystins. Toxins (Basel) 2019; 11:toxins11120714. [PMID: 31817927 PMCID: PMC6950048 DOI: 10.3390/toxins11120714] [Citation(s) in RCA: 206] [Impact Index Per Article: 41.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/02/2019] [Accepted: 12/04/2019] [Indexed: 11/22/2022] Open
Abstract
Hepatotoxic microcystins (MCs) are the most widespread class of cyanotoxins and the one that has most often been implicated in cyanobacterial toxicosis. One of the main challenges in studying and monitoring MCs is the great structural diversity within the class. The full chemical structure of the first MC was elucidated in the early 1980s and since then, the number of reported structural analogues has grown steadily and continues to do so, thanks largely to advances in analytical methodology. The structures of some of these analogues have been definitively elucidated after chemical isolation using a combination of techniques including nuclear magnetic resonance, amino acid analysis, and tandem mass spectrometry (MS/MS). Others have only been tentatively identified using liquid chromatography-MS/MS without chemical isolation. An understanding of the structural diversity of MCs, the genetic and environmental controls for this diversity and the impact of structure on toxicity are all essential to the ongoing study of MCs across several scientific disciplines. However, because of the diversity of MCs and the range of approaches that have been taken for characterizing them, comprehensive information on the state of knowledge in each of these areas can be challenging to gather. We have conducted an in-depth review of the literature surrounding the identification and toxicity of known MCs and present here a concise review of these topics. At present, at least 279 MCs have been reported and are tabulated here. Among these, about 20% (55 of 279) appear to be the result of chemical or biochemical transformations of MCs that can occur in the environment or during sample handling and extraction of cyanobacteria, including oxidation products, methyl esters, or post-biosynthetic metabolites. The toxicity of many MCs has also been studied using a range of different approaches and a great deal of variability can be observed between reported toxicities, even for the same congener. This review will help clarify the current state of knowledge on the structural diversity of MCs as a class and the impacts of structure on toxicity, as well as to identify gaps in knowledge that should be addressed in future research.
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Affiliation(s)
- Noureddine Bouaïcha
- Écologie, Systématique et Évolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91405 Orsay, France; (A.D.); (N.Y.B.)
- Correspondence: ; Tel.: +33-(01)69154990; Fax: +33-(0)169155696
| | - Christopher O. Miles
- Biotoxin Metrology, National Research Council Canada, 1411 Oxford St, Halifax, NS B3H 3Z1, Canada; (C.O.M.); (D.G.B.)
| | - Daniel G. Beach
- Biotoxin Metrology, National Research Council Canada, 1411 Oxford St, Halifax, NS B3H 3Z1, Canada; (C.O.M.); (D.G.B.)
| | - Zineb Labidi
- Laboratoire Biodiversité et Pollution des Écosystèmes, Faculté des Sciences de la Nature et de la Vie, Université Chadli Bendjedid d’El Taref, 36000 El Taref, Algeria;
| | - Amina Djabri
- Écologie, Systématique et Évolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91405 Orsay, France; (A.D.); (N.Y.B.)
- Laboratoire Biodiversité et Pollution des Écosystèmes, Faculté des Sciences de la Nature et de la Vie, Université Chadli Bendjedid d’El Taref, 36000 El Taref, Algeria;
| | - Naila Yasmine Benayache
- Écologie, Systématique et Évolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91405 Orsay, France; (A.D.); (N.Y.B.)
| | - Tri Nguyen-Quang
- Biofluids and Biosystems Modeling (BBML), Faculty of Agriculture, Dalhousie University, 39 Cox Road, Truro, B2N 5E3 Nova Scotia, Canada;
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Simultaneous Detection of 14 Microcystin Congeners from Tissue Samples Using UPLC- ESI-MS/MS and Two Different Deuterated Synthetic Microcystins as Internal Standards. Toxins (Basel) 2019; 11:toxins11070388. [PMID: 31269739 PMCID: PMC6669509 DOI: 10.3390/toxins11070388] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 06/21/2019] [Accepted: 06/28/2019] [Indexed: 02/02/2023] Open
Abstract
Cyanobacterial microcystins (MCs), potent serine/threonine-phosphatase inhibitors, pose an increasing threat to humans. Current detection methods are optimised for water matrices with only a few MC congeners simultaneously detected. However, as MC congeners are known to differ in their toxicity, methods are needed that simultaneously quantify the congeners present, thus allowing for summary hazard and risk assessment. Moreover, detection of MCs should be expanded to complex matrices, e.g., blood and tissue samples, to verify in situ MC concentrations, thus providing for improved exposure assessment and hazard interpretation. To achieve this, we applied two synthetic deuterated MC standards and optimised the tissue extraction protocol for the simultaneous detection of 14 MC congeners in a single ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) run. This procedure was validated using plasma and liver homogenates of mice (male and female) spiked with deuterated MC standards. For proof of concept, tissue and plasma samples from mice i.p. injected with MC-LR and MC-LF were analysed. While MC-LF was detected in all tissue samples of both sexes, detection of MC-LR was restricted to liver samples of male mice, suggesting different toxicokinetics in males, e.g., transport, conjugation or protein binding. Thus, deconjugation/-proteinisation steps should be employed to improve detection of bound MC.
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10
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Foss AJ, Miles CO, Samdal IA, Løvberg KE, Wilkins AL, Rise F, Jaabæk JAH, McGowan PC, Aubel MT. Analysis of free and metabolized microcystins in samples following a bird mortality event. HARMFUL ALGAE 2018; 80:117-129. [PMID: 30502804 DOI: 10.1016/j.hal.2018.10.006] [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: 05/14/2018] [Revised: 09/28/2018] [Accepted: 10/15/2018] [Indexed: 06/09/2023]
Abstract
In the summer of 2012, over 750 dead and dying birds were observed at the Paul S. Sarbanes Ecosystem Restoration Project at Poplar Island, Maryland, USA (Chesapeake Bay). Clinical signs suggested avian botulism, but an ongoing dense Microcystis bloom was present in an impoundment on the island. Enzyme-linked immunosorbent assay (ELISA) analysis of a water sample indicated 6000 ng mL-1 of microcystins (MCs). LC-UV/MS analysis confirmed the presence of MC-LR and a high concentration of an unknown MC congener (m/z 1037.5). The unknown MC was purified and confirmed to be [D-Leu1]MC-LR using NMR spectroscopy, LC-HRMS and LC-MS2, which slowly converted to [D-Leu1,Glu(OMe)6]MC-LR during storage in MeOH. Lyophilized algal material from the bloom was further characterized using LC-HRMS and LC-MS2 in combination with chemical derivatizations, and an additional 24 variants were detected, including MCs conjugated to Cys, GSH and γ-GluCys and their corresponding sulfoxides. Mallard (Anas platyrhynchos) livers were tested to confirm MC exposure. Two broad-specificity MC ELISAs and LC-MS2 were used to measure free MCs, while 'total' MCs were estimated by both MMPB (3-methoxy-2-methyl-4-phenylbutyric acid) and thiol de-conjugation techniques. Free microcystins in the livers (63-112 ng g-1) accounted for 33-41% of total microcystins detected by de-conjugation and MMPB techniques. Free [D-Leu1]MC-LR was quantitated in tissues at 25-67 ng g-1 (LC-MS2). The levels of microcystin varied based on analytical method used, highlighting the need to develop a comprehensive analysis strategy to elucidate the etiology of bird mortality events when microcystin-producing HABs are present.
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Affiliation(s)
- Amanda J Foss
- GreenWater Laboratories/CyanoLab, 205 Zeagler Drive, Palatka, FL, 32177, United States.
| | - Christopher O Miles
- Norwegian Veterinary Institute, P. O. Box 750 Sentrum, N-0106, Oslo, Norway; Measurement Science and Standards, National Research Council, 1411 Oxford Street, Halifax, NS, B3H 3Z1, Canada
| | - Ingunn A Samdal
- Norwegian Veterinary Institute, P. O. Box 750 Sentrum, N-0106, Oslo, Norway
| | - Kjersti E Løvberg
- Norwegian Veterinary Institute, P. O. Box 750 Sentrum, N-0106, Oslo, Norway
| | - Alistair L Wilkins
- Norwegian Veterinary Institute, P. O. Box 750 Sentrum, N-0106, Oslo, Norway; Chemistry Department, University of Waikato, Private Bag 3105, 3240, Hamilton, New Zealand
| | - Frode Rise
- Department of Chemistry, University of Oslo, P.O. Box 1033, N-0315, Oslo, Norway
| | - J Atle H Jaabæk
- Department of Chemistry, University of Oslo, P.O. Box 1033, N-0315, Oslo, Norway
| | - Peter C McGowan
- U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, Annapolis, MD, United States
| | - Mark T Aubel
- GreenWater Laboratories/CyanoLab, 205 Zeagler Drive, Palatka, FL, 32177, United States
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11
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Li L, Wang Q, Lyu R, Yu L, Su S, Du FS, Li ZC. Synthesis of a ROS-responsive analogue of poly(ε-caprolactone) by the living ring-opening polymerization of 1,4-oxathiepan-7-one. Polym Chem 2018. [DOI: 10.1039/c8py00798e] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A well-defined ROS-responsive block amphiphilic diblock copolymer PEO-b-POTO was synthesized to elucidate the oxidative degradation mechanism in assemblies.
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Affiliation(s)
- Linggao Li
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key Laboratory of Polymer Chemistry & Physics of Ministry of Education
- Department of Polymer Science & Engineering
- College of Chemistry and Molecular Engineering
- Center for Soft Matter Science & Engineering
| | - Qiyuan Wang
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key Laboratory of Polymer Chemistry & Physics of Ministry of Education
- Department of Polymer Science & Engineering
- College of Chemistry and Molecular Engineering
- Center for Soft Matter Science & Engineering
| | - Ruiliang Lyu
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key Laboratory of Polymer Chemistry & Physics of Ministry of Education
- Department of Polymer Science & Engineering
- College of Chemistry and Molecular Engineering
- Center for Soft Matter Science & Engineering
| | - Li Yu
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key Laboratory of Polymer Chemistry & Physics of Ministry of Education
- Department of Polymer Science & Engineering
- College of Chemistry and Molecular Engineering
- Center for Soft Matter Science & Engineering
| | - Shan Su
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key Laboratory of Polymer Chemistry & Physics of Ministry of Education
- Department of Polymer Science & Engineering
- College of Chemistry and Molecular Engineering
- Center for Soft Matter Science & Engineering
| | - Fu-Sheng Du
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key Laboratory of Polymer Chemistry & Physics of Ministry of Education
- Department of Polymer Science & Engineering
- College of Chemistry and Molecular Engineering
- Center for Soft Matter Science & Engineering
| | - Zi-Chen Li
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key Laboratory of Polymer Chemistry & Physics of Ministry of Education
- Department of Polymer Science & Engineering
- College of Chemistry and Molecular Engineering
- Center for Soft Matter Science & Engineering
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