1
|
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.
Collapse
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
| |
Collapse
|
3
|
Ding L, Bar-Shalom R, Aharonovich D, Kurisawa N, Patial G, Li S, He S, Yan X, Iwasaki A, Suenaga K, Zhu C, Luo H, Tian F, Fares F, Naman CB, Luzzatto-Knaan T. Metabolomic Characterization of a cf. Neolyngbya Cyanobacterium from the South China Sea Reveals Wenchangamide A, a Lipopeptide with In Vitro Apoptotic Potential in Colon Cancer Cells. Mar Drugs 2021; 19:md19070397. [PMID: 34356822 PMCID: PMC8307421 DOI: 10.3390/md19070397] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 12/17/2022] Open
Abstract
Metabolomics can be used to study complex mixtures of natural products, or secondary metabolites, for many different purposes. One productive application of metabolomics that has emerged in recent years is the guiding direction for isolating molecules with structural novelty through analysis of untargeted LC-MS/MS data. The metabolomics-driven investigation and bioassay-guided fractionation of a biomass assemblage from the South China Sea dominated by a marine filamentous cyanobacteria, cf. Neolyngbya sp., has led to the discovery of a natural product in this study, wenchangamide A (1). Wenchangamide A was found to concentration-dependently cause fast-onset apoptosis in HCT116 human colon cancer cells in vitro (24 h IC50 = 38 μM). Untargeted metabolomics, by way of MS/MS molecular networking, was used further to generate a structural proposal for a new natural product analogue of 1, here coined wenchangamide B, which was present in the organic extract and bioactive sub-fractions of the biomass examined. The wenchangamides are of interest for anticancer drug discovery, and the characterization of these molecules will facilitate the future discovery of related natural products and development of synthetic analogues.
Collapse
Affiliation(s)
- Lijian Ding
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, Department of Marine Pharmacy, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315800, China; (L.D.); (G.P.); (S.L.); (S.H.); (X.Y.)
- Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa 31905, Israel;
| | - Rinat Bar-Shalom
- Department of Human Biology, Faculty of Life Sciences, University of Haifa, Haifa 31905, Israel; (R.B.-S.); (F.F.)
| | - Dikla Aharonovich
- Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa 31905, Israel;
| | - Naoaki Kurisawa
- Department of Chemistry, Keio University, 3-14-1, Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan; (N.K.); (A.I.); (K.S.)
| | - Gaurav Patial
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, Department of Marine Pharmacy, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315800, China; (L.D.); (G.P.); (S.L.); (S.H.); (X.Y.)
| | - Shuang Li
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, Department of Marine Pharmacy, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315800, China; (L.D.); (G.P.); (S.L.); (S.H.); (X.Y.)
| | - Shan He
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, Department of Marine Pharmacy, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315800, China; (L.D.); (G.P.); (S.L.); (S.H.); (X.Y.)
| | - Xiaojun Yan
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, Department of Marine Pharmacy, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315800, China; (L.D.); (G.P.); (S.L.); (S.H.); (X.Y.)
| | - Arihiro Iwasaki
- Department of Chemistry, Keio University, 3-14-1, Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan; (N.K.); (A.I.); (K.S.)
- Key Laboratory of Medicinal and Edible Plant Resources of Hainan Province, Hainan Vocational University of Science and Technology, Haikou 571126, China; (C.Z.); (H.L.); (F.T.)
| | - Kiyotake Suenaga
- Department of Chemistry, Keio University, 3-14-1, Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan; (N.K.); (A.I.); (K.S.)
- Key Laboratory of Medicinal and Edible Plant Resources of Hainan Province, Hainan Vocational University of Science and Technology, Haikou 571126, China; (C.Z.); (H.L.); (F.T.)
| | - Chengcong Zhu
- Key Laboratory of Medicinal and Edible Plant Resources of Hainan Province, Hainan Vocational University of Science and Technology, Haikou 571126, China; (C.Z.); (H.L.); (F.T.)
| | - Haixi Luo
- Key Laboratory of Medicinal and Edible Plant Resources of Hainan Province, Hainan Vocational University of Science and Technology, Haikou 571126, China; (C.Z.); (H.L.); (F.T.)
| | - Fuli Tian
- Key Laboratory of Medicinal and Edible Plant Resources of Hainan Province, Hainan Vocational University of Science and Technology, Haikou 571126, China; (C.Z.); (H.L.); (F.T.)
| | - Fuad Fares
- Department of Human Biology, Faculty of Life Sciences, University of Haifa, Haifa 31905, Israel; (R.B.-S.); (F.F.)
| | - C. Benjamin Naman
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, Department of Marine Pharmacy, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315800, China; (L.D.); (G.P.); (S.L.); (S.H.); (X.Y.)
- Key Laboratory of Medicinal and Edible Plant Resources of Hainan Province, Hainan Vocational University of Science and Technology, Haikou 571126, China; (C.Z.); (H.L.); (F.T.)
- Correspondence: (C.B.N.); (T.L.-K.)
| | - Tal Luzzatto-Knaan
- Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa 31905, Israel;
- Correspondence: (C.B.N.); (T.L.-K.)
| |
Collapse
|
4
|
Lefler FW, Berthold DE, Laughinghouse HD. The occurrence of Affixifilum gen. nov. and Neolyngbya (Oscillatoriaceae) in South Florida (USA), with the description of A. floridanum sp. nov. and N. biscaynensis sp. nov. JOURNAL OF PHYCOLOGY 2021; 57:92-110. [PMID: 32853414 DOI: 10.1111/jpy.13065] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 07/02/2020] [Accepted: 07/20/2020] [Indexed: 06/11/2023]
Abstract
South Florida (USA) has a subtropical to tropical climate with an extensive and diverse coastline that supports the growth of benthic cyanobacterial mats (BCMs). These BCMs are widespread and potentially house numerous bioactive compounds; however, the extent of the cyanobacterial diversity within these mats remains largely unknown. To elucidate this diversity, BCMs from select locations in South Florida were sampled and isolated into unicyanobacterial cultures for morphological and molecular studies. Phylogenetic relationships of isolated taxa were assessed using the markers 16S rRNA and 16S-23S rRNA ITS by both maximum likelihood and Bayesian inference. We propose Affixifilum gen. nov. based on morphological characteristics and the 16S rRNA phylogeny. Two species are included: Affixifilum granulosum comb nov. (=Neolyngbya granulosa) found in Brazil and Florida (USA) and A. floridanum sp. nov. Several other features, including pair-wise distance of 16S rRNA and 16S-23S rRNA ITS, 16S-23S rRNA ITS secondary structure, morphology, and ecology, provide support for Affixifilum. We also propose the transfer of Lyngbya regalis to Neolyngbya as N. regalis comb. nov. and include the description of one novel species, N. biscaynensis sp. nov.
Collapse
Affiliation(s)
- Forrest W Lefler
- Agronomy Department, Fort Lauderdale Research and Education Center, University of Florida / IFAS, Davie, Florida, 33314, USA
| | - David E Berthold
- Agronomy Department, Fort Lauderdale Research and Education Center, University of Florida / IFAS, Davie, Florida, 33314, USA
| | - H Dail Laughinghouse
- Agronomy Department, Fort Lauderdale Research and Education Center, University of Florida / IFAS, Davie, Florida, 33314, USA
| |
Collapse
|
5
|
Untangling filamentous marine cyanobacterial diversity from the coast of South Florida with the description of Vermifilaceae fam. nov. and three new genera: Leptochromothrix gen. nov., Ophiophycus gen. nov., and Vermifilum gen. nov. Mol Phylogenet Evol 2020; 160:107010. [PMID: 33186689 DOI: 10.1016/j.ympev.2020.107010] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 10/14/2020] [Accepted: 11/04/2020] [Indexed: 11/24/2022]
Abstract
Benthic cyanobacterial mats are an integral component of aquatic communities in tropical marine waters. These mats can develop into massive nuisances at risk of expansion due to climate change. The extent of diversity occurring within these mats, still remains largely unexplored, especially in Florida. To reveal this diversity, coastal environments of South Florida were sampled and subsequently processed for isolation and systematic identification. Three new genera are proposed based on the molecular phylogeny, morphology, and ecology. These new genera are characterized by discoid cells and homocytous, unbranched filaments without sheaths. Individual genus morphological differences include either rounded bent, rounded, or conical rounded apical cells. A unique molecular fingerprint including a base pair insert within the 16S rRNA gene sequence and genetic similarities facilitates the delimitation of a novel family Vermifilaceae. Using the polyphasic approach, our research presents three new genera and four new species of marine cyanobacteria inhabiting coastal ecosystems of South Florida.
Collapse
|