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Dr. Isabel Bravo
Instituto Español de Oceanografía (IEO), Centro Oceanográfico de Vigo, 36390, Vigo, Spain

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0 Harmful Algae
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0 Harmful dinoflagellates
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Review
Published: 29 June 2021 in Toxins
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Marine biotoxins have been frequently implicated in morbidity and mortality events in numerous species of birds worldwide. Nevertheless, their effects on seabirds have often been overlooked and the associated ecological impact has not been extensively studied. On top of that, the number of published studies confirming by analyses the presence of marine biotoxins from harmful algal blooms (HABs) in seabirds, although having increased in recent years, is still quite low. This review compiles information on studies evidencing the impact of HAB toxins on marine birds, with a special focus on the effects of paralytic and amnesic shellfish toxins (PSTs and ASTs). It is mainly centered on studies in which the presence of PSTs and/or ASTs in seabird samples was demonstrated through analyses. The analytical techniques commonly employed, the tissues selected and the adjustments done in protocols for processing seabird matrixes are summarized. Other topics covered include the role of different vectors in the seabird intoxications, information on clinical signs in birds affected by PSTs and ASTs, and multifactorial causes which could aggravate the syndromes. Close collaboration between seabird experts and marine biotoxins researchers is needed to identify and report the potential involvement of HABs and their toxins in the mortality events. Future studies on the PSTs and ASTs pharmacodynamics, together with the establishment of lethal doses in various seabird species, are also necessary. These studies would aid in the selection of the target organs for toxins analyses and in the postmortem intoxication diagnoses.

ACS Style

Begoña Ben-Gigirey; Lucía Soliño; Isabel Bravo; Francisco Rodríguez; María Casero. Paralytic and Amnesic Shellfish Toxins Impacts on Seabirds, Analyses and Management. Toxins 2021, 13, 454 .

AMA Style

Begoña Ben-Gigirey, Lucía Soliño, Isabel Bravo, Francisco Rodríguez, María Casero. Paralytic and Amnesic Shellfish Toxins Impacts on Seabirds, Analyses and Management. Toxins. 2021; 13 (7):454.

Chicago/Turabian Style

Begoña Ben-Gigirey; Lucía Soliño; Isabel Bravo; Francisco Rodríguez; María Casero. 2021. "Paralytic and Amnesic Shellfish Toxins Impacts on Seabirds, Analyses and Management." Toxins 13, no. 7: 454.

Journal article
Published: 12 November 2020 in Journal of Marine Science and Engineering
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The relationship between the ciguatoxin-producer benthic dinoflagellate Gambierdiscus and other epibenthic dinoflagellates in the Canary Islands was examined in macrophyte samples obtained from two locations of Fuerteventura Island in September 2016. The genera examined included Coolia, Gambierdiscus, Ostreopsis, Prorocentrum, Scrippsiella, Sinophysis, and Vulcanodinium. Distinct assemblages among these benthic dinoflagellates and preferential macroalgal communities were observed. Vulcanodinium showed the highest cell concentrations (81.6 × 103 cells gr−1 wet weight macrophyte), followed by Ostreopsis (25.2 × 103 cells gr−1 wet weight macrophyte). These two species were most represented at a station (Playitas) characterized by turfy Rhodophytes. In turn, Gambierdiscus (3.8 × 103 cells gr−1 wet weight macrophyte) and Sinophysis (2.6 × 103 cells gr−1 wet weight macrophyte) were mostly found in a second station (Cotillo) dominated by Rhodophytes and Phaeophytes. The influence of macrophyte’s thallus architecture on the abundance of dinoflagellates was observed. Filamentous morphotypes followed by macroalgae arranged in entangled clumps presented more richness of epiphytic dinoflagellates. Morphometric analysis was applied to Gambierdiscus specimens. By large, G. excentricus was the most abundant species and G. australes occupied the second place. The toxigenic potential of some of the genera/species distributed in the benthic habitats of the Canary coasts, together with the already known presence of ciguatera in the region, merits future studies on possible transmission of their toxins in the marine food chain.

ACS Style

Isabel Bravo; Francisco Rodríguez; Isabel Ramilo; Julio Afonso-Carrillo. Epibenthic Harmful Marine Dinoflagellates from Fuerteventura (Canary Islands), with Special Reference to the Ciguatoxin-Producing Gambierdiscus. Journal of Marine Science and Engineering 2020, 8, 909 .

AMA Style

Isabel Bravo, Francisco Rodríguez, Isabel Ramilo, Julio Afonso-Carrillo. Epibenthic Harmful Marine Dinoflagellates from Fuerteventura (Canary Islands), with Special Reference to the Ciguatoxin-Producing Gambierdiscus. Journal of Marine Science and Engineering. 2020; 8 (11):909.

Chicago/Turabian Style

Isabel Bravo; Francisco Rodríguez; Isabel Ramilo; Julio Afonso-Carrillo. 2020. "Epibenthic Harmful Marine Dinoflagellates from Fuerteventura (Canary Islands), with Special Reference to the Ciguatoxin-Producing Gambierdiscus." Journal of Marine Science and Engineering 8, no. 11: 909.

Journal article
Published: 16 September 2020 in Harmful Algae
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Chromosomal markers of the diversity and evolution of dinoflagellates are scarce because the genomes of these organisms are unique among eukaryotes in terms of their base composition and chromosomal structure. Similarly, a lack of appropriate tools has hindered studies of the chromosomal localization of 5S ribosomal DNA (rDNA) in the nucleosome-less chromosomes of dinoflagellates. In this study, we isolated and cloned 5S rDNA sequences from various toxin-producing species of the genus Alexandrium and developed a fluorescence in situ hybridization (FISH) probe that allows their chromosomal localization. Our results can be summarized as follows: 1) The 5S rDNA unit is composed of a highly conserved 122-bp coding region and an intergenic spacer (IGS), the length and sequence of which are variable even within strains. 2) Three different IGS types, one containing the U6 small nuclear RNA (snRNA) gene, were found among four of the studied species (A. minutum, A. tamarense, A. catenella and A. pacificum). 3) In all strains investigated by FISH (A. minutum, A. tamarense, A. pacificum, A. catenella, A. andersonii and A. ostenfeldii), 5S rDNA gene arrays were separate from the nucleolar organizer region, which contains the genes for the large 45S pre-ribosomal RNA. 4) One to three 5S rDNA sites per haploid genome were detected, depending on the strains/species. Intraspecific variability in the number of 5S rDNA sites was determined among strains of A. minutum and A. pacificum. 5) 5S rDNA is a useful chromosomal marker of mitosis progression and can be employed to differentiate vegetative (haploid) vs. planozygotes (diploid) cells. Thus, the FISH probe (oligo-Dino5Smix5) developed in this study facilitates analyses of the diversity, cell cycle and life stages of the genus Alexandrium.

ACS Style

Alfredo de Bustos; Rosa I Figueroa; Marta Sixto; Isabel Bravo; Ángeles Cuadrado. The 5S rRNA genes in Alexandrium: their use as a FISH chromosomal marker in studies of the diversity, cell cycle and sexuality of dinoflagellates. Harmful Algae 2020, 98, 101903 .

AMA Style

Alfredo de Bustos, Rosa I Figueroa, Marta Sixto, Isabel Bravo, Ángeles Cuadrado. The 5S rRNA genes in Alexandrium: their use as a FISH chromosomal marker in studies of the diversity, cell cycle and sexuality of dinoflagellates. Harmful Algae. 2020; 98 ():101903.

Chicago/Turabian Style

Alfredo de Bustos; Rosa I Figueroa; Marta Sixto; Isabel Bravo; Ángeles Cuadrado. 2020. "The 5S rRNA genes in Alexandrium: their use as a FISH chromosomal marker in studies of the diversity, cell cycle and sexuality of dinoflagellates." Harmful Algae 98, no. : 101903.

Journal article
Published: 21 February 2020 in Toxins
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In the last decade, several outbreaks of ciguatera fish poisoning (CFP) have been reported in the Canary Islands (central northeast Atlantic Ocean), confirming ciguatera as an emerging alimentary risk in this region. Five Gambierdiscus species, G. australes, G. excentricus, G. silvae, G. carolinianus and G. caribaeus, have been detected in macrophytes from this area and are known to produce the ciguatoxins (CTXs) that cause CFP. A characterization of the toxicity of these species is the first step in identifying locations in the Canary Islands at risk of CFP. Therefore, in this study the toxicity of 63 strains of these five Gambierdiscus species were analysed using the erythrocyte lysis assay to evaluate their maitotoxin (MTX) content. In addition, 20 of the strains were also analysed in a neuroblastoma Neuro-2a (N2a) cytotoxicity assay to determine their CTX-like toxicity. The results allowed the different species to be grouped according to their ratios of CTX-like and MTX-like toxicity. MTX-like toxicity was especially high in G. excentricus and G. australes but much lower in the other species and lowest in G. silvae. CTX-like toxicity was highest in G. excentricus, which produced the toxin in amounts ranging between 128.2 ± 25.68 and 510.6 ± 134.2 fg CTX1B equivalents (eq) cell−1 (mean ± SD). In the other species, CTX concentrations were as follows: G. carolinianus (100.84 ± 18.05 fg CTX1B eq cell−1), G. australes (31.1 ± 0.56 to 107.16 ± 21.88 fg CTX1B eq cell−1), G. silvae (12.19 ± 0.62 to 76.79 ± 4.97 fg CTX1B eq cell−1) and G. caribaeus (

ACS Style

Araceli E. Rossignoli; Angels Tudó; Isabel Bravo; Patricio A. Díaz; Jorge Diogène; Pilar Riobó. Toxicity Characterisation of Gambierdiscus Species from the Canary Islands. Toxins 2020, 12, 134 .

AMA Style

Araceli E. Rossignoli, Angels Tudó, Isabel Bravo, Patricio A. Díaz, Jorge Diogène, Pilar Riobó. Toxicity Characterisation of Gambierdiscus Species from the Canary Islands. Toxins. 2020; 12 (2):134.

Chicago/Turabian Style

Araceli E. Rossignoli; Angels Tudó; Isabel Bravo; Patricio A. Díaz; Jorge Diogène; Pilar Riobó. 2020. "Toxicity Characterisation of Gambierdiscus Species from the Canary Islands." Toxins 12, no. 2: 134.

Journal article
Published: 19 July 2019 in Toxins
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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.

ACS Style

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 Style

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 (7):423.

Chicago/Turabian Style

Isabel 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.

Original article
Published: 05 July 2019 in Cytometry Part A
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Scrippsiella is a cosmopolitan dinoflagellate genus that is able to form Harmful Algal Blooms in coastal waters. The large physiological, morphological, and genetic variability that characterizes this genus suggest the existence of cryptic species. In this study, flow cytometric analyses were carried out to compare the cell cycle and life cycle of two Scrippsiella strains from two different species: Scrippsiella ramonii (VGO1053) and Scrippsiella acuminata (S3V). Both species were also investigated by internally transcribed spacer rDNA sequencing and high‐performance liquid chromatography‐based pigment analyses. The reddish‐brown color of S. acuminata and yellowish‐green hue of S. ramonii were consistent with the quantitative differences determined in their pigment profiles. Our results indicate that the cell cycle is light‐controlled and that it differs in the two species. S‐phase was detected during the light period in both, whereas the G2/M phase occurred during the light period in S. ramonii but under dark conditions in S. acuminata. The detection of 4C stages, mobile zygotes (planozygotes), and resting cysts in S. ramonii (nonclonal) provided convincing evidence of sexuality in this species. Sexual related processes were not found in the clonal S. acuminata strain, suggesting its heterothallic behavior (i.e., the need for outcrossing). The differences in the genome size of these species were examined as well. © 2019 International Society for Advancement of Cytometry

ACS Style

Elena Fagín; Isabel Bravo; José Luis Garrido; Francisco Rodríguez; Rosa Figueroa. Scrippsiella acuminata versus Scrippsiella ramonii : A Physiological Comparison. Cytometry Part A 2019, 95, 985 -996.

AMA Style

Elena Fagín, Isabel Bravo, José Luis Garrido, Francisco Rodríguez, Rosa Figueroa. Scrippsiella acuminata versus Scrippsiella ramonii : A Physiological Comparison. Cytometry Part A. 2019; 95 (9):985-996.

Chicago/Turabian Style

Elena Fagín; Isabel Bravo; José Luis Garrido; Francisco Rodríguez; Rosa Figueroa. 2019. "Scrippsiella acuminata versus Scrippsiella ramonii : A Physiological Comparison." Cytometry Part A 95, no. 9: 985-996.

Journal article
Published: 14 January 2019 in Toxins
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Blooms of Dinophysis acuminata occur every year in Galicia (northwest Spain), between spring and autumn. These blooms contaminate shellfish with lipophilic toxins and cause lengthy harvesting bans. They are often followed by short-lived blooms of Dinophysis acuta, associated with northward longshore transport, at the end of the upwelling season. During the summers of 1989 and 1990, dense blooms of D. acuta developed in situ, initially co-occurring with D. acuminata and later with the paralytic shellfish toxin-producer Gymnodinium catenatum. Unexplored data from three cruises carried out before, during, and following autumn blooms (13–14, 27–28 September and 11–12 October) in 1990 showed D. acuta distribution in shelf waters within the 50 m and 130 m isobaths, delimited by the upwelling front. A joint review of monitoring data from Galicia and Portugal provided a mesoscale view of anomalies in SST and other hydroclimatic factors associated with a northward displacement of the center of gravity of D. acuta populations. At the microscale, re-examination of the vertical segregation of cell maxima in the light of current knowledge, improved our understanding of niche differentiation between the two species of Dinophysis. Results here improve local transport models and forecast of Dinophysis events, the main cause of shellfish harvesting bans in the most important mussel production area in Europe.

ACS Style

Patricio A. Díaz; Beatriz Reguera; Teresa Moita; Isabel Bravo; Manuel Ruiz-Villarreal; Santiago Fraga. Mesoscale Dynamics and Niche Segregation of Two Dinophysis Species in Galician-Portuguese Coastal Waters. Toxins 2019, 11, 37 .

AMA Style

Patricio A. Díaz, Beatriz Reguera, Teresa Moita, Isabel Bravo, Manuel Ruiz-Villarreal, Santiago Fraga. Mesoscale Dynamics and Niche Segregation of Two Dinophysis Species in Galician-Portuguese Coastal Waters. Toxins. 2019; 11 (1):37.

Chicago/Turabian Style

Patricio A. Díaz; Beatriz Reguera; Teresa Moita; Isabel Bravo; Manuel Ruiz-Villarreal; Santiago Fraga. 2019. "Mesoscale Dynamics and Niche Segregation of Two Dinophysis Species in Galician-Portuguese Coastal Waters." Toxins 11, no. 1: 37.

Regular article
Published: 01 December 2017 in Journal of Phycology
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The family Ceratocoryaceae includes the genera Ceratocorys, Protoceratium, and Schuettiella, whose phylogenetic relationships are poorly known. Here, the new non‐yessotoxin‐producing species of the genus Ceratocorys, Ceratocorys mariaovidiorum sp. nov., previously reported as the toxic Protoceratium reticulatum, is described from examinations by light and scanning electron microscopy, molecular phylogeny, and toxin analyses. The species description is made from culture samples of strains CCMP1740 and CCMP404 from USA waters. Ceratocorys mariaovidiorum is globular and has thick and strongly reticulated plates with one pore within each reticule, just like P. reticulatum, but the key difference between the two species is the presence of five precingular plates in C. mariaovidiorum instead of six as in P. reticulatum. The thecal plate formula is Po, 4′, 0a, 5″, 6c, ~7s, 5‴, 0p, 2′′′′. The apical pore plate is oval with a λ‐shaped pore. The first apical plate is narrow with a ventral pore on the right anterior side; it contacts the apical pore plate and its contact with the anterior sulcal plate is slight or absent. The fourth precingular plate of other Gonyaulacales is absent. Ceratocorys mariaovidiorum may have small spines on the second antapical plate. A phylogenetic study based on internal transcribed spacer/5.8SrDNA supports the morphological classification of C. mariaovidiorum as a new species of Ceratocorys and in a different clade from P. reticulatum.

ACS Style

Pablo Salgado; Santiago Fraga; Francisco Rodríguez; Pilar Riobó; Isabel Bravo. Ceratocorys mariaovidiorum sp. nov. (Gonyaulacales), a new dinoflagellate species previously reported as Protoceratium reticulatum. Journal of Phycology 2017, 54, 126 -137.

AMA Style

Pablo Salgado, Santiago Fraga, Francisco Rodríguez, Pilar Riobó, Isabel Bravo. Ceratocorys mariaovidiorum sp. nov. (Gonyaulacales), a new dinoflagellate species previously reported as Protoceratium reticulatum. Journal of Phycology. 2017; 54 (1):126-137.

Chicago/Turabian Style

Pablo Salgado; Santiago Fraga; Francisco Rodríguez; Pilar Riobó; Isabel Bravo. 2017. "Ceratocorys mariaovidiorum sp. nov. (Gonyaulacales), a new dinoflagellate species previously reported as Protoceratium reticulatum." Journal of Phycology 54, no. 1: 126-137.

Regular article
Published: 01 December 2017 in Journal of Phycology
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A planktonic‐benthic relationship has been described for many dinoflagellate species as part of their ecological strategy to overcome highly variable aquatic environments. Here, the phylogenetically and morphologically related marine dinoflagellates Protoceratium reticulatum and Ceratocorys mariaovidiorum were studied in relation to an unknown benthic life form. In vivo and fixed samples from cultures were analyzed in detail by light and scanning electron microscopy. In both species, a cell type with a morphology different from that of vegetative cells was observed in cultures grown until stationary phase. This cell type was always benthic, swimming sporadically only when it was disturbed. Its main feature included a strong dorsoventral compression. These cells originated from vegetative cells whose protoplasm underwent a progressive flattening, resulting in a gradual detachment of the reticulate and thick thecal plates and the formation of very thin non‐reticulated new plates with pores. When returned to fresh full‐strength medium, the cells recovered their spherical vegetative‐like morphology, including new reticulated thick plates and subsequent cell divisions. The kinetics of flattened cell formation showed that in both species, this cell type increased exponentially until the onset of the culture stationary phase and then decreased. The results of this study are discussed in the context of the planktonic–benthic coupling in dinoflagellate life cycles, including those newly appreciated to be well adapted to the benthic environment.

ACS Style

Pablo Salgado; Santiago Fraga; Francisco Rodriguez; Isabel Bravo. Benthic flattened cells of the phylogenetically related marine dinoflagellates Protoceratium reticulatum and Ceratocorys mariaovidiorum (Gonyaulacales): a new type of cyst? Journal of Phycology 2017, 54, 138 -149.

AMA Style

Pablo Salgado, Santiago Fraga, Francisco Rodriguez, Isabel Bravo. Benthic flattened cells of the phylogenetically related marine dinoflagellates Protoceratium reticulatum and Ceratocorys mariaovidiorum (Gonyaulacales): a new type of cyst? Journal of Phycology. 2017; 54 (1):138-149.

Chicago/Turabian Style

Pablo Salgado; Santiago Fraga; Francisco Rodriguez; Isabel Bravo. 2017. "Benthic flattened cells of the phylogenetically related marine dinoflagellates Protoceratium reticulatum and Ceratocorys mariaovidiorum (Gonyaulacales): a new type of cyst?" Journal of Phycology 54, no. 1: 138-149.

Journal article
Published: 01 September 2017 in Harmful Algae
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ACS Style

Pablo Salgado; Rosa I. Figueroa; Isabel Ramilo; Isabel Bravo. The life history of the toxic marine dinoflagellate Protoceratium reticulatum (Gonyaulacales) in culture. Harmful Algae 2017, 68, 67 -81.

AMA Style

Pablo Salgado, Rosa I. Figueroa, Isabel Ramilo, Isabel Bravo. The life history of the toxic marine dinoflagellate Protoceratium reticulatum (Gonyaulacales) in culture. Harmful Algae. 2017; 68 ():67-81.

Chicago/Turabian Style

Pablo Salgado; Rosa I. Figueroa; Isabel Ramilo; Isabel Bravo. 2017. "The life history of the toxic marine dinoflagellate Protoceratium reticulatum (Gonyaulacales) in culture." Harmful Algae 68, no. : 67-81.

Published erratum
Published: 01 September 2017 in Harmful Algae
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ACS Style

Francisco Rodríguez; Santiago Fraga; Isabel Ramilo; Pilar Rial; Rosa Isabel Figueroa; Pilar Riobó; Isabel Bravo. Corrigendum to ‘Canary Islands (NE Atlantic) as a biodiversity hotspot of Gambierdiscus: Implications for future trends of ciguatera in the area’. Harmful Algae 2017, 68, 273 .

AMA Style

Francisco Rodríguez, Santiago Fraga, Isabel Ramilo, Pilar Rial, Rosa Isabel Figueroa, Pilar Riobó, Isabel Bravo. Corrigendum to ‘Canary Islands (NE Atlantic) as a biodiversity hotspot of Gambierdiscus: Implications for future trends of ciguatera in the area’. Harmful Algae. 2017; 68 ():273.

Chicago/Turabian Style

Francisco Rodríguez; Santiago Fraga; Isabel Ramilo; Pilar Rial; Rosa Isabel Figueroa; Pilar Riobó; Isabel Bravo. 2017. "Corrigendum to ‘Canary Islands (NE Atlantic) as a biodiversity hotspot of Gambierdiscus: Implications for future trends of ciguatera in the area’." Harmful Algae 68, no. : 273.

Journal article
Published: 01 July 2017 in Harmful Algae
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In the present study the geographical distribution, abundance and composition of Gambierdiscus was described over a 600km longitudinal scale in the Canary Islands. Samples for cell counts, isolation and identification of Gambierdiscus were obtained from five islands (El Hierro, Tenerife, Gran Canaria, Fuerteventura and Lanzarote). Average densities of Gambierdiscus spp. between 0 and 2200cellsg(-1) blot dry weight of macrophyte were recorded. Morphological (light microscopy and SEM techniques) and molecular analyses (LSU and SSU rDNA sequencing of cultures and single cells from the field) of Gambierdiscus was performed. Five Gambierdiscus species (G. australes, G. caribaeus, G. carolinianus, G. excentricus and G. silvae), together with a new putative species (Gambierdiscus ribotype 3) were identified. These results suggest that some cases of CFP in the region could be associated with the accumulation of ciguatoxins in the marine food web acquired from local populations of Gambierdiscus. This unexpected high diversity of Gambierdiscus species in an area which a priori is not under risk of ciguatera, hints at an ancient settlement of Gambierdiscus populations, likely favored by warmer climate conditions in the Miocene Epoch (when oldest current Canary Islands were created), in contrast with cooler present ones. Currently, warming trends associated with climate change could contribute to extend favorable environmental conditions in the area for Gambierdiscus growth especially during winter months.

ACS Style

Francisco Rodríguez; Santiago Fraga; Isabel Ramilo; Pilar Rial; Rosa Isabel Figueroa; Pilar Riobó; Isabel Bravo. “Canary Islands (NE Atlantic) as a biodiversity ‘hotspot’ of Gambierdiscus: Implications for future trends of ciguatera in the area”. Harmful Algae 2017, 67, 131 -143.

AMA Style

Francisco Rodríguez, Santiago Fraga, Isabel Ramilo, Pilar Rial, Rosa Isabel Figueroa, Pilar Riobó, Isabel Bravo. “Canary Islands (NE Atlantic) as a biodiversity ‘hotspot’ of Gambierdiscus: Implications for future trends of ciguatera in the area”. Harmful Algae. 2017; 67 ():131-143.

Chicago/Turabian Style

Francisco Rodríguez; Santiago Fraga; Isabel Ramilo; Pilar Rial; Rosa Isabel Figueroa; Pilar Riobó; Isabel Bravo. 2017. "“Canary Islands (NE Atlantic) as a biodiversity ‘hotspot’ of Gambierdiscus: Implications for future trends of ciguatera in the area”." Harmful Algae 67, no. : 131-143.

Journal article
Published: 01 September 2016 in Harmful Algae
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A new benthic toxic dinoflagellate is described from the Celebes Sea. Gambierdiscus balechii sp. nov. was isolated from seaweeds growing in tidal ponds. Its morphology was studied by means of LM and SEM; G. balechii has a very ornamented theca, a hatchet shaped second apical plate, a narrow second antapical plate and an asymmetrical third precigular plate, a unique combination of characters among Gambierdiscus species. It has a very wide size range with widths from 36 to 88 μm. Phylogenetic analyses of two G. balechii strains, based on LSU rRNA (D8–D10) and partial SSUrRNA sequences confirmed that these clustererd in its’ own group, separated from the rest of Gambierdiscus species and with G. pacificus, G. belizeanus and G. scabrosus as its closest relatives. Thecate cysts are described from culture as non motile vegetative-like cells which germinated after being isolated and transferred to fresh medium. Mouse tests showed that this species is toxic and hence it is a potential cause of ciguatera in the Celebes Sea.

ACS Style

Santiago Fraga; Francisco Rodríguez; Pilar Riobó; Isabel Bravo. Gambierdiscus balechii sp. nov (Dinophyceae), a new benthic toxic dinoflagellate from the Celebes Sea (SW Pacific Ocean). Harmful Algae 2016, 58, 93 -105.

AMA Style

Santiago Fraga, Francisco Rodríguez, Pilar Riobó, Isabel Bravo. Gambierdiscus balechii sp. nov (Dinophyceae), a new benthic toxic dinoflagellate from the Celebes Sea (SW Pacific Ocean). Harmful Algae. 2016; 58 ():93-105.

Chicago/Turabian Style

Santiago Fraga; Francisco Rodríguez; Pilar Riobó; Isabel Bravo. 2016. "Gambierdiscus balechii sp. nov (Dinophyceae), a new benthic toxic dinoflagellate from the Celebes Sea (SW Pacific Ocean)." Harmful Algae 58, no. : 93-105.

Research article
Published: 04 December 2015 in PLOS ONE
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Alexandrium ostenfeldii is present in a wide variety of environments in coastal areas worldwide and is the only dinoflagellate known species that produces paralytic shellfish poisoning (PSP) toxins and two types of cyclic imines, spirolides (SPXs) and gymnodimines (GYMs). The increasing frequency of A. ostenfeldii blooms in the Baltic Sea has been attributed to the warming water in this region. To learn more about the optimal environmental conditions favoring the proliferation of A. ostenfeldii and its complex toxicity, the effects of temperature and salinity on the kinetics of both the growth and the net toxin production of this species were examined using a factorial design and a response-surface analysis (RSA). The results showed that the growth of Baltic A. ostenfeldii occurs over a wide range of temperatures and salinities (12.5–25.5°C and 5–21, respectively), with optimal growth conditions achieved at a temperature of 25.5°C and a salinity of 11.2. Together with the finding that a salinity > 21 was the only growth-limiting factor detected for this strain, this study provides important insights into the autecology and population distribution of this species in the Baltic Sea. The presence of PSP toxins, including gonyautoxin (GTX)-3, GTX-2, and saxitoxin (STX), and GYMs (GYM-A and GYM-B/-C analogues) was detected under all temperature and salinity conditions tested and in the majority of the cases was concomitant with both the exponential growth and stationary phases of the dinoflagellate’s growth cycle. Toxin concentrations were maximal at temperatures and salinities of 20.9°C and 17 for the GYM-A analogue and > 19°C and 15 for PSP toxins, respectively. The ecological implications of the optimal conditions for growth and toxin production of A. ostenfeldii in the Baltic Sea are discussed.

ACS Style

Pablo Salgado; Jose A. Vazquez; Pilar Riobo; José M. Franco; Rosa I. Figueroa; Anke Kremp; Isabel Bravo. A Kinetic and Factorial Approach to Study the Effects of Temperature and Salinity on Growth and Toxin Production by the Dinoflagellate Alexandrium ostenfeldii from the Baltic Sea. PLOS ONE 2015, 10, e0143021 .

AMA Style

Pablo Salgado, Jose A. Vazquez, Pilar Riobo, José M. Franco, Rosa I. Figueroa, Anke Kremp, Isabel Bravo. A Kinetic and Factorial Approach to Study the Effects of Temperature and Salinity on Growth and Toxin Production by the Dinoflagellate Alexandrium ostenfeldii from the Baltic Sea. PLOS ONE. 2015; 10 (12):e0143021.

Chicago/Turabian Style

Pablo Salgado; Jose A. Vazquez; Pilar Riobo; José M. Franco; Rosa I. Figueroa; Anke Kremp; Isabel Bravo. 2015. "A Kinetic and Factorial Approach to Study the Effects of Temperature and Salinity on Growth and Toxin Production by the Dinoflagellate Alexandrium ostenfeldii from the Baltic Sea." PLOS ONE 10, no. 12: e0143021.

Research article
Published: 23 November 2015 in PLOS ONE
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Dinoflagellates are haploid eukaryotic microalgae in which rapid proliferation causes dense blooms, with harmful health and economic effects to humans. The proliferation mode is mainly asexual, as the sexual cycle is believed to be rare and restricted to stressful environmental conditions. However, sexuality is key to explaining the recurrence of many dinoflagellate blooms because in many species the fate of the planktonic zygotes (planozygotes) is the formation of resistant cysts in the seabed (encystment). Nevertheless, recent research has shown that individually isolated planozygotes in the lab can enter other routes besides encystment, a behavior of which the relevance has not been explored at the population level. In this study, using imaging flow cytometry, cell sorting, and Fluorescence In Situ Hybridization (FISH), we followed DNA content and nuclear changes in a population of the toxic dinoflagellate Alexandrium minutum that was induced to encystment. Our results first show that planozygotes behave like a population with an “encystment-independent” division cycle, which is light-controlled and follows the same Light:Dark (L:D) pattern as the cycle governing the haploid mitosis. Resting cyst formation was the fate of just a small fraction of the planozygotes formed and was restricted to a period of strongly limited nutrient conditions. The diploid-haploid turnover between L:D cycles was consistent with two-step meiosis. However, the diel and morphological division pattern of the planozygote division also suggests mitosis, which would imply that this species is not haplontic, as previously considered, but biphasic, because individuals could undergo mitotic divisions in both the sexual (diploid) and the asexual (haploid) phases. We also report incomplete genome duplication processes. Our work calls for a reconsideration of the dogma of rare sex in dinoflagellates.

ACS Style

Rosa I. Figueroa; Carlos Dapena; Isabel Bravo; Angeles Cuadrado. The Hidden Sexuality of Alexandrium Minutum: An Example of Overlooked Sex in Dinoflagellates. PLOS ONE 2015, 10, e0142667 -e0142667.

AMA Style

Rosa I. Figueroa, Carlos Dapena, Isabel Bravo, Angeles Cuadrado. The Hidden Sexuality of Alexandrium Minutum: An Example of Overlooked Sex in Dinoflagellates. PLOS ONE. 2015; 10 (11):e0142667-e0142667.

Chicago/Turabian Style

Rosa I. Figueroa; Carlos Dapena; Isabel Bravo; Angeles Cuadrado. 2015. "The Hidden Sexuality of Alexandrium Minutum: An Example of Overlooked Sex in Dinoflagellates." PLOS ONE 10, no. 11: e0142667-e0142667.

Journal article
Published: 22 October 2015 in Aquatic Microbial Ecology
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Marta Turon; Elisabet Alacid; Rosa Figueroa; A Reñé; Isabel Ferrera; Isabel Bravo; I Ramilo; Esther Garcés. Genetic and phenotypic diversity characterization of natural populations of the parasitoid Parvilucifera sinerae. Aquatic Microbial Ecology 2015, 76, 117 -132.

AMA Style

Marta Turon, Elisabet Alacid, Rosa Figueroa, A Reñé, Isabel Ferrera, Isabel Bravo, I Ramilo, Esther Garcés. Genetic and phenotypic diversity characterization of natural populations of the parasitoid Parvilucifera sinerae. Aquatic Microbial Ecology. 2015; 76 (2):117-132.

Chicago/Turabian Style

Marta Turon; Elisabet Alacid; Rosa Figueroa; A Reñé; Isabel Ferrera; Isabel Bravo; I Ramilo; Esther Garcés. 2015. "Genetic and phenotypic diversity characterization of natural populations of the parasitoid Parvilucifera sinerae." Aquatic Microbial Ecology 76, no. 2: 117-132.

Journal article
Published: 01 September 2015 in Toxicon
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14 páginas, 7 figuras, 5 tablasAmong toxin-producing dinoflagellates of the genus Alexandrium, Alexandrium ostenfeldii is the only species able to produce paralytic shellfish poisoning (PSP) toxins, spirolides (SPXs) and gymnodimines (GYMs). In this study we characterized and compared three A. ostenfeldii strains isolated from the Baltic, Mediterranean, and southern Chile Seas with respect to their toxin profiles, morphology, and phylogeny. Toxin analyses by HPLC–FD and LC–HRMS revealed differences in the toxin profiles of the three strains. The PSP toxin profiles of the southern Chile and Baltic strains were largely the same and included gonyautoxin (GTX)-3, GTX-2, and saxitoxin (STX), although the total PSP toxin content of the Chilean strain (105.83 ± 72.15 pg cell−1) was much higher than that of the Baltic strain (4.04 ± 1.93 pg cell−1). However, the Baltic strain was the only strain that expressed detectable amounts of analogues of GYM-A and GYM-B/-C (48.27 ± 26.12 pg GYM-A equivalents cell−1). The only toxin expressed by the Mediterranean strain was 13-desmethyl SPX-C (13dMeC; 2.85 ± 4.76 pg cell−1). Phylogenetic analysis based on the LSU rRNA showed that the studied strains belonged to distinct molecular clades. The toxin profiles determined in this study provide further evidence of the taxonomic complexity of this speciesThis work is a contribution of Unidad Asociada “Microalgas Nocivas” (CSIC-IEO) and was carried out at the Instituto Español de Oceanografía (IEO) in Vigo and was financially supported by the CCVIEO project and CICAN-2013-40671-R (Ministry of Economy and Competitiveness). P. Salgado is a researcher at the IFOP, which provides financial support for his doctoral stayingPeer reviewe

ACS Style

Pablo Salgado; Pilar Riobó; Francisco Rodriguez; José M. Franco; Isabel Bravo. Differences in the toxin profiles of Alexandrium ostenfeldii (Dinophyceae) strains isolated from different geographic origins: Evidence of paralytic toxin, spirolide, and gymnodimine. Toxicon 2015, 103, 85 -98.

AMA Style

Pablo Salgado, Pilar Riobó, Francisco Rodriguez, José M. Franco, Isabel Bravo. Differences in the toxin profiles of Alexandrium ostenfeldii (Dinophyceae) strains isolated from different geographic origins: Evidence of paralytic toxin, spirolide, and gymnodimine. Toxicon. 2015; 103 ():85-98.

Chicago/Turabian Style

Pablo Salgado; Pilar Riobó; Francisco Rodriguez; José M. Franco; Isabel Bravo. 2015. "Differences in the toxin profiles of Alexandrium ostenfeldii (Dinophyceae) strains isolated from different geographic origins: Evidence of paralytic toxin, spirolide, and gymnodimine." Toxicon 103, no. : 85-98.

Journal article
Published: 01 February 2015 in Protist
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Elucidation of the cell cycle of dinoflagellates is essential to understand the processes leading to their massive proliferations, known as harmful algal blooms. In this study, we used imaging flow cytometry (IFC) to monitor the changes in DNA content and nuclear and cell morphology that occur during clonal growth of the toxic species Alexandrium minutum Halim. Our results indicate that the population was in S phase (C→2C DNA content) during the light period, whereas haploid cells with a C DNA content peaked only during a short interval of the dark period. The timing of the phases, identified based on the nuclear morphology and cytoplasmic-to-nuclear (CNR) ratio of the cells, suggests that the length of the G2/M phase is regulated by nutrient levels whereas the beginning of S phase is clock controlled. In addition we found that up to 7% of individual cells achieved a DNA content higher than 2C, indicative of either zygote formation and replication (homothallism), or of double-haploid cells able to divide (polyploid forms). Cells belonging to different cell cycle phases (G1-S-G2/M) could be readily discriminated based on nuclear size. Our study provides evidence of cell-cycle plasticity during clonal growth and unambiguously characterizes the cell-cycle phases of this dinoflagellate species.Postprin

ACS Style

Carlos Dapena; Isabel Bravo; Angeles Cuadrado; Rosa Isabel Figueroa. Nuclear and Cell Morphological Changes during the Cell Cycle and Growth of the Toxic Dinoflagellate Alexandrium minutum. Protist 2015, 166, 146 -160.

AMA Style

Carlos Dapena, Isabel Bravo, Angeles Cuadrado, Rosa Isabel Figueroa. Nuclear and Cell Morphological Changes during the Cell Cycle and Growth of the Toxic Dinoflagellate Alexandrium minutum. Protist. 2015; 166 (1):146-160.

Chicago/Turabian Style

Carlos Dapena; Isabel Bravo; Angeles Cuadrado; Rosa Isabel Figueroa. 2015. "Nuclear and Cell Morphological Changes during the Cell Cycle and Growth of the Toxic Dinoflagellate Alexandrium minutum." Protist 166, no. 1: 146-160.

Journal article
Published: 01 December 2014 in Harmful Algae
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Isabel Bravo; Rosa Figueroa; Santiago Fraga. Cellular and nuclear morphological variability within a single species of the toxigenic dinoflagellate genus Gambierdiscus: Relationship to life-cycle processes. Harmful Algae 2014, 40, 1 -8.

AMA Style

Isabel Bravo, Rosa Figueroa, Santiago Fraga. Cellular and nuclear morphological variability within a single species of the toxigenic dinoflagellate genus Gambierdiscus: Relationship to life-cycle processes. Harmful Algae. 2014; 40 ():1-8.

Chicago/Turabian Style

Isabel Bravo; Rosa Figueroa; Santiago Fraga. 2014. "Cellular and nuclear morphological variability within a single species of the toxigenic dinoflagellate genus Gambierdiscus: Relationship to life-cycle processes." Harmful Algae 40, no. : 1-8.

Journal article
Published: 03 January 2014 in Microorganisms
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The life cycle of many dinoflagellates includes at least one nonflagellated benthic stage (cyst). In the literature, the different types of dinoflagellate cysts are mainly defined based on morphological (number and type of layers in the cell wall) and functional (long- or short-term endurance) differences. These characteristics were initially thought to clearly distinguish pellicle (thin-walled) cysts from resting (double-walled) dinoflagellate cysts. The former were considered short-term (temporal) and the latter long-term (resting) cysts. However, during the last two decades further knowledge has highlighted the great intricacy of dinoflagellate life histories, the ecological significance of cyst stages, and the need to clarify the functional and morphological complexities of the different cyst types. Here we review and, when necessary, redefine the concepts of resting and pellicle cysts, examining both their structural and their functional characteristics in the context of the life cycle strategies of several dinoflagellate species.

ACS Style

I. (Isabel) Bravo; R.I. (Rosa Isabel) Figueroa. Towards an Ecological Understanding of Dinoflagellate Cyst Functions. Microorganisms 2014, 2, 11 -32.

AMA Style

I. (Isabel) Bravo, R.I. (Rosa Isabel) Figueroa. Towards an Ecological Understanding of Dinoflagellate Cyst Functions. Microorganisms. 2014; 2 (1):11-32.

Chicago/Turabian Style

I. (Isabel) Bravo; R.I. (Rosa Isabel) Figueroa. 2014. "Towards an Ecological Understanding of Dinoflagellate Cyst Functions." Microorganisms 2, no. 1: 11-32.