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Two high-mass polar compounds were observed in aqueous side-fractions from the purification of okadaic acid (1) and dinophysistoxin-2 (2) from Dinophysis blooms in Spain and Norway. These were isolated and shown to be 24-O-β-d-glucosides of 1 and 2 (4 and 5, respectively) by nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, and enzymatic hydrolysis. These, together with standards of 1, 2, dinophysistoxin-1 (3), and a synthetic specimen of 7-deoxy-1 (7), combined with an understanding of their mass spectrometric fragmentation patterns, were then used to identify 1–5, the 24-O-β-d-glucoside of dinophysistoxin-1 (6), 7, 7-deoxy-2 (8), and 7-deoxy-3 (9) in a range of extracts from Dinophysis blooms, Dinophysis cultures, and contaminated shellfish from Spain, Norway, Ireland, Canada, and New Zealand. A range of Prorocentrumlima cultures was also examined by liquid chromatography–high resolution tandem mass spectrometry (LC–HRMS/MS) and was found to contain 1, 3, 7, and 9. However, although 4–6 were not detected in these cultures, low levels of putative glycosides with the same exact masses as 4 and 6 were present. The potential implications of these findings for the toxicology, metabolism, and biosynthesis of the okadaic acid group of marine biotoxins are briefly discussed.
Alistair L. Wilkins; Thomas Rundberget; Morten Sandvik; Frode Rise; Brent K. Knudsen; Jane Kilcoyne; Beatriz Reguera; Pilar Rial; Elliott J. Wright; Sabrina D. Giddings; Michael J. Boundy; Cheryl Rafuse; Christopher O. Miles. Identification of 24-O-β-d-Glycosides and 7-Deoxy-Analogues of Okadaic Acid and Dinophysistoxin-1 and -2 in Extracts from Dinophysis Blooms, Dinophysis and Prorocentrum Cultures, and Shellfish in Europe, North America and Australasia. Toxins 2021, 13, 510 .
AMA StyleAlistair L. Wilkins, Thomas Rundberget, Morten Sandvik, Frode Rise, Brent K. Knudsen, Jane Kilcoyne, Beatriz Reguera, Pilar Rial, Elliott J. Wright, Sabrina D. Giddings, Michael J. Boundy, Cheryl Rafuse, Christopher O. Miles. Identification of 24-O-β-d-Glycosides and 7-Deoxy-Analogues of Okadaic Acid and Dinophysistoxin-1 and -2 in Extracts from Dinophysis Blooms, Dinophysis and Prorocentrum Cultures, and Shellfish in Europe, North America and Australasia. Toxins. 2021; 13 (8):510.
Chicago/Turabian StyleAlistair L. Wilkins; Thomas Rundberget; Morten Sandvik; Frode Rise; Brent K. Knudsen; Jane Kilcoyne; Beatriz Reguera; Pilar Rial; Elliott J. Wright; Sabrina D. Giddings; Michael J. Boundy; Cheryl Rafuse; Christopher O. Miles. 2021. "Identification of 24-O-β-d-Glycosides and 7-Deoxy-Analogues of Okadaic Acid and Dinophysistoxin-1 and -2 in Extracts from Dinophysis Blooms, Dinophysis and Prorocentrum Cultures, and Shellfish in Europe, North America and Australasia." Toxins 13, no. 8: 510.
Dinoflagellates belonging to the genus Gambierdiscus produce ciguatoxins (CTXs), which are metabolized in fish to more toxic forms and subsequently cause ciguatera fish poisoning (CFP) in humans. Five species of Gambierdiscus have been described from the Canary Islands, where CTXs in fish have been reported since 2004. Here we present new data on the distribution of Gambierdiscus species in the Canary archipelago and specifically from two islands, La Palma and La Gomera, where the genus had not been previously reported. Gambierdiscus spp. concentrations were low, with maxima of 88 and 29 cells·g−1 wet weight in samples from La Gomera and La Palma, respectively. Molecular analysis (LSUrRNA gene sequences) revealed differences in the species distribution between the two islands: only G. excentricus was detected at La Palma whereas four species, G. australes, G. caribaeus, G. carolinianus, and G. excentricus, were identified from La Gomera. Morphometric analyses of cultured cells of the five Canary Islands species and of field specimens from La Gomera included cell size and a characterization of three thecal arrangement traits: (1) the shape of the 2′ plate, (2) the position of Po in the anterior suture of the 2′ plate, and (3) the length–width relationship of the 2″″ plate. Despite the wide morphological variability within the culture and field samples, the use of two or more variables allowed the discrimination of two species in the La Gomera samples: G. cf. excentricus and G. cf. silvae. A comparison of the molecular data with the morphologically based classification demonstrated important coincidences, such as the dominance of G. excentricus, but also differences in the species composition of Gambierdiscus, as G. caribaeus was detected in the study area only by using molecular methods.
Isabel Bravo; Francisco Rodriguez; Isabel Ramilo; Pilar Rial; Santiago Fraga. Ciguatera-Causing Dinoflagellate Gambierdiscus spp. (Dinophyceae) in a Subtropical Region of North Atlantic Ocean (Canary Islands): Morphological Characterization and Biogeography. Toxins 2019, 11, 423 .
AMA StyleIsabel Bravo, Francisco Rodriguez, Isabel Ramilo, Pilar Rial, Santiago Fraga. Ciguatera-Causing Dinoflagellate Gambierdiscus spp. (Dinophyceae) in a Subtropical Region of North Atlantic Ocean (Canary Islands): Morphological Characterization and Biogeography. Toxins. 2019; 11 (7):423.
Chicago/Turabian StyleIsabel Bravo; Francisco Rodriguez; Isabel Ramilo; Pilar Rial; Santiago Fraga. 2019. "Ciguatera-Causing Dinoflagellate Gambierdiscus spp. (Dinophyceae) in a Subtropical Region of North Atlantic Ocean (Canary Islands): Morphological Characterization and Biogeography." Toxins 11, no. 7: 423.
Kleptoplastic mixotrophic species of the genus Dinophysis are cultured by feeding with the ciliate Mesodinium rubrum, itself a kleptoplastic mixotroph, that in turn feeds on cryptophytes of the Teleaulax/Plagioselmis/Geminigera (TPG) clade. Optimal culture media for phototrophic growth of D. acuminata and D. acuta from the Galician Rías (northwest Spain) and culture media and cryptophyte prey for M. rubrum from Huelva (southwest Spain) used to feed Dinophysis, were investigated. Phototrophic growth rates and yields were maximal when D. acuminata and D. acuta were grown in ammonia-containing K(-Si) medium versus f/2(-Si) or L1(-Si) media. Dinophysis acuminata cultures were scaled up to 18 L in a photobioreactor. Large differences in cell toxin quota were observed in the same Dinophysis strains under different experimental conditions. Yields and duration of exponential growth were maximal for M. rubrum from Huelva when fed Teleaulax amphioxeia from the same region, versus T. amphioxeia from the Galician Rías or T. minuta and Plagioselmis prolonga. Limitations for mass cultivation of northern Dinophysis strains with southern M. rubrum were overcome using more favorable (1:20) Dinophysis: Mesodinium ratios. These subtleties highlight the ciliate strain-specific response to prey and its importance to mass production of M. rubrum and Dinophysis cultures.
Jorge Hernández-Urcera; Pilar Rial; María García-Portela; Patricia Lourés; Jane Kilcoyne; Francisco Rodríguez; Amelia Fernández-Villamarín; Beatriz Reguera. Notes on the Cultivation of Two Mixotrophic Dinophysis Species and Their Ciliate Prey Mesodinium rubrum. Toxins 2018, 10, 505 .
AMA StyleJorge Hernández-Urcera, Pilar Rial, María García-Portela, Patricia Lourés, Jane Kilcoyne, Francisco Rodríguez, Amelia Fernández-Villamarín, Beatriz Reguera. Notes on the Cultivation of Two Mixotrophic Dinophysis Species and Their Ciliate Prey Mesodinium rubrum. Toxins. 2018; 10 (12):505.
Chicago/Turabian StyleJorge Hernández-Urcera; Pilar Rial; María García-Portela; Patricia Lourés; Jane Kilcoyne; Francisco Rodríguez; Amelia Fernández-Villamarín; Beatriz Reguera. 2018. "Notes on the Cultivation of Two Mixotrophic Dinophysis Species and Their Ciliate Prey Mesodinium rubrum." Toxins 10, no. 12: 505.
11 pages, 5 figures, 1 table.The asexual and sexual reproduction of Ostreopsis cf. ovata was studied in the field and in cultures isolated from two locations in the Mediterranean Sea. Asexual division took place in the motile stage by the sharing of theca (desmoschisis). High cell-size variability and differences in division capability were detected in the cultures. Thecal analyses and nuclear division patterns allowed characterization of the different phases of dividing cells obtained during an in situ cell-cycle sampling performed off Llavaneres beach (Northeast Spain). During the 45-h cycle, binucleated cells accounted for 2.6% of the population. Division was initiated with the onset of dusk and reached a maximum 3–4 h before dawn. No dividing cells were detected after 09:00 AM. Sexuality occurred both in cultures and in natural populations of O. cf. ovata. Mating gamete pairs were the only sexual stages that could be distinguished from vegetative stages. The differences between these pairs and dividing cells are described herein. None of the individually isolated gamete pairs underwent fusion nor encystment, instead, in most of them one member of the gamete pair divided. Rather than plasmogamy, there was evidence of nuclear migration from one gamete to the other. Pellicle cysts, thin-walled cysts, and thecate cysts were also identified and studied. These cysts, embedded in abundant mucilage in a bloom-derived incubated sample, were able to germinate for as long as 6 months after their formation. Our results suggest that they constitute the overwintering population that causes recurrent blooms of O. cf. ovata in some areas of the Mediterranean Sea.This work was supported by the Spanish national project EBITOX (CTQ2008-06754-C04-04). We also thank the CCVIEO-Microalgae Culture Collection of Instituto Español de Oceanografía for providing culture strains.[SS]Peer reviewe
Isabel Bravo; Magda Vila; Silvia Casabianca; Francisco Rodriguez; Pilar Rial; Pilar Riobó; Antonella Penna. Life cycle stages of the benthic palytoxin-producing dinoflagellate Ostreopsis cf. ovata (Dinophyceae). Harmful Algae 2012, 18, 24 -34.
AMA StyleIsabel Bravo, Magda Vila, Silvia Casabianca, Francisco Rodriguez, Pilar Rial, Pilar Riobó, Antonella Penna. Life cycle stages of the benthic palytoxin-producing dinoflagellate Ostreopsis cf. ovata (Dinophyceae). Harmful Algae. 2012; 18 ():24-34.
Chicago/Turabian StyleIsabel Bravo; Magda Vila; Silvia Casabianca; Francisco Rodriguez; Pilar Rial; Pilar Riobó; Antonella Penna. 2012. "Life cycle stages of the benthic palytoxin-producing dinoflagellate Ostreopsis cf. ovata (Dinophyceae)." Harmful Algae 18, no. : 24-34.
8 páginas, 1 apéndice, 6 figurasDinophysis tripos (Gourret, 1883) exhibits marked morphological variability and its small and intermediate forms may get confused with those of Dinophysis caudata when their blooms co-occur. D. tripos has been included in the list of toxin-producing Dinophysis spp. based on one single analysis by liquid chromatography with fluorescence detection (LC–FLD). After many years of absence, a D. tripos bloom occurred in the Galician Rias Baixas that was not associated with harvesting closures. Morphological, toxicological and genetic characteristics of D. tripos were described from cultures fed with the ciliate Myrionecta rubra grown on a cryptophyte (Teleaulax amphioxeia). Toxin analyses (LC–MS) of plankton concentrates rich in D. tripos and cultures of the same species confirmed the presence of pectenotoxin-2 (PTX-2). Small and intermediate forms of D. tripos appeared in culture and allowed a good description of morphological features that differentiate them from those of D. caudata/Dinophysis diegensis. Phylogenetic analyses based on the ITS/5.8S rDNA region placed D. tripos in a subclade including D. caudata, Dinophysis fortii and Dinophysis infundibulus. Identical ITS/5.8S rDNA sequences were obtained for normal and small cells of D. tripos. This is the first report of the presence of PTX2 in D. tripos and of the establishment of mixotrophic cultures of this species.This work was funded by coordinated project DIGEDINO (CTM2009-12988-C02-01) and by EU FP7 project MIDTALPeer reviewe
Francisco Rodríguez; Laura Escalera; Beatriz Reguera; Pilar Rial; Pilar Riobó; Themis De Jesús Da Silva. Morphological variability, toxinology and genetics of the dinoflagellate Dinophysis tripos (Dinophysiaceae, Dinophysiales). Harmful Algae 2012, 13, 26 -33.
AMA StyleFrancisco Rodríguez, Laura Escalera, Beatriz Reguera, Pilar Rial, Pilar Riobó, Themis De Jesús Da Silva. Morphological variability, toxinology and genetics of the dinoflagellate Dinophysis tripos (Dinophysiaceae, Dinophysiales). Harmful Algae. 2012; 13 ():26-33.
Chicago/Turabian StyleFrancisco Rodríguez; Laura Escalera; Beatriz Reguera; Pilar Rial; Pilar Riobó; Themis De Jesús Da Silva. 2012. "Morphological variability, toxinology and genetics of the dinoflagellate Dinophysis tripos (Dinophysiaceae, Dinophysiales)." Harmful Algae 13, no. : 26-33.