Harmful Algae最新文献

{"title":"Divergent responses of an armored and an unarmored dinoflagellate to ocean acidification","authors":"Wei-Ping Zhang ,&nbsp;Shuo-Yu Zhang ,&nbsp;Yang Zhou ,&nbsp;Wen-Jing Sun ,&nbsp;Shu-Feng Zhang ,&nbsp;Jae-Seong Lee ,&nbsp;Minghua Wang ,&nbsp;Da-Zhi Wang","doi":"10.1016/j.hal.2024.102772","DOIUrl":"10.1016/j.hal.2024.102772","url":null,"abstract":"<div><div>Dinoflagellates, both armored and unarmored, with distinct cell wall difference, are being affected by elevated CO₂-induced ocean acidification (OA). However, their specific responses to OA are not well understood. In this study, we investigated the physiological and molecular response of the armored species <em>Prorocentrum obtusidens</em> and the unarmored species <em>Karenia mikimotoi</em> to OA over a 28-day period. The results show that the two species responded differently to OA. Cell growth rate, particulate organic carbon (POC) content, and the activities of C₄ pathway enzymes decreased in <em>P. obtusidens</em> under future acidified ocean condition (pH 7.8, 1000 μatm <em>p</em>CO₂), but the activities of carbonic anhydrase (CA), ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO), and superoxide dismutase (SOD) increased. Whereas cell growth rate, contents of Chl <em>a</em> and PON, and SOD activity altered insignificantly in <em>K. mikimotoi</em>, but contents of POC and total carbohydrate, and the activity of RubisCO increased while the activities of CA and C₄ pathway enzymes decreased. Transcriptomic analysis indicates that genes associated with antioxidative response, heat shock protein, proteasome, signal transduction, ribosome, and pH regulation were up-regulated in <em>P. obtusidens</em> but down-regulated in <em>K. mikimotoi</em>. Notably, the synthesis of soluble organic matter (i.e., spermidine and trehalose) was enhanced in <em>K. mikimotoi</em>, thereby regulating intracellular pH and improving stress resistance. This study highlights the divergent response of the armored and unarmored dinoflagellates to OA, with the unarmored dinoflagellate exhibiting a higher ability to withstand this stressor. Therefore, caution should be exercised when predicting the behavior and the eventual fate of dinoflagellates in the future acidified ocean.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"141 ","pages":"Article 102772"},"PeriodicalIF":5.5,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Target-oriented element activation and functional group synthesis lead to high quality modified clay for Prorocentrum donghaiense control","authors":"Xihua Cao ,&nbsp;Mingjiao Wang ,&nbsp;Fan Liu ,&nbsp;Xiuxian Song ,&nbsp;Zhiming Yu","doi":"10.1016/j.hal.2024.102770","DOIUrl":"10.1016/j.hal.2024.102770","url":null,"abstract":"<div><div>Single source with series modifications (SSSM) is a new method to modify clay surfaces by activating clay mineral resources for harmful algal blooms control. In this study, the optimal preparation conditions for this method were obtained using response surface methodology. Based on the material analysis, an important way to obtain modified clay (MC) with the excellent <em>Prorocentrum donghaiense</em> removal performance was explored and the optimum preparation conditions were as follows: calcination temperature 750 °C, alkali neutralization pH 3.7 and clay supplementation ratio 1.3:1. Under these conditions, the calcination treatment can effectively activate the aluminum element in the clay lattice and obtain the largest amount of highly active Al ^IV and Al ^V, which are readily released from the lattice as activated aluminum. When the alkali neutralization pH was adjusted to 3.7, the activated aluminum was hydrolyzed and induced into highly positively charged polyhydroxyaluminum compounds. The supplemented kaolin increased the yield of the MC product by surface convergence of the activated aluminum in the system. As a result, the optimized MC can form large particle size flocs with good regeneration and stability during the algal removal process, which greatly improved its ability to coagulate and sediment algal cells. Overall, the MC prepared by the SSSM method achieved high algal removal efficiency through targeted element activation and functional group shaping.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"141 ","pages":"Article 102770"},"PeriodicalIF":5.5,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metabolic transformation of paralytic shellfish toxins in the mussel Mytilus galloprovincialis under different exposure modes","authors":"Guanchao Zheng ,&nbsp;Hanyu Che ,&nbsp;Haiyan Wu ,&nbsp;Yuxiang Deng ,&nbsp;Mengmeng Guo ,&nbsp;Jixing Peng ,&nbsp;Qianqian Geng ,&nbsp;Zhijun Tan","doi":"10.1016/j.hal.2024.102771","DOIUrl":"10.1016/j.hal.2024.102771","url":null,"abstract":"<div><div><em>Gymnodinium catenatum</em> is a widely distributed toxic marine dinoflagellate that produces paralytic shellfish toxins (PSTs). It is prone to causing algal blooms and poses a serious threat to the shellfish industry and human health. Previous studies have shown that when algal blooms occur, shellfish can accumulate PSTs in their bodies due to filtration. In this study, mussels (<em>Mytilus galloprovincialis</em>) were fed with <em>G. catenatum</em> at different fixed or varied cell density over time, with the latter designed to mimic the changes in algal cell density over time in the wild. The PST concentration in the mussels was positively correlated with the number of algal cells, and PSTs rapidly accumulated in the mussels under both feeding modes. Compared with constant feeding in the low feeding group, variable cell density feeding over time was more conducive to the accumulation of PSTs in <em>M. galloprovincialis</em>. An obvious toxin transformation process was also detected in the mussels, which transformed the less toxic gonyautoxins-5 and -6 and <em>N</em>-sulfocarbamoyl gonyautoxin-3 ingested from <em>G. catenatum</em> into the more toxic decarbamoyl gonyautoxin-2, decarbamoyl saxitoxin, and decarbamoyl neosaxitoxin. The ratio of epimer pairs, α:β, tended to stabilize when the toxin concentration was highest, and it increased rapidly after mussels stopped consuming toxigenic algae. These results suggested that the formation of α-stable toxoids mainly occurred during the process of toxin depuration. Toxins were also transformed from low to high toxicity, and α-stable toxoids were formed mainly in the hepatopancreas. These results provided basic data for better understanding of the laws governing metabolic transformation of PSTs in bivalves during algal blooms.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"141 ","pages":"Article 102771"},"PeriodicalIF":5.5,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intraspecific genetic diversity with unrestricted gene flow in the domoic acid-producing diatom Nitzschia navis-varingica (Bacillariophyceae) from the Western Pacific","authors":"Suh Nih Tan ,&nbsp;Yuichi Kotaki ,&nbsp;Sing Tung Teng ,&nbsp;Hong Chang Lim ,&nbsp;Chunlei Gao ,&nbsp;Nina Lundholm ,&nbsp;Matthias Wolf ,&nbsp;Haifeng Gu ,&nbsp;Po Teen Lim ,&nbsp;Chui Pin Leaw","doi":"10.1016/j.hal.2024.102769","DOIUrl":"10.1016/j.hal.2024.102769","url":null,"abstract":"<div><div>The benthic pennate diatom <em>Nitzschia navis</em>-<em>varingica</em>, known for producing domoic acid (DA) and its isomers, is widely distributed in the Western Pacific (WP) region. To investigate the genetic differentiation and gene flow patterns among the populations in the WP, the genetic diversity of 354 strains of <em>N. navis-varingica</em> was analysed using two nuclear-encoded rDNA loci: the large subunit rDNA (LSU rDNA) and the internal transcribed spacer 2 (ITS2). Frustule morphology of each strain was examined by TEM. The LSU rDNA phylogeny revealed a monophyletic lineage encompassing all strains, with sequence divergences of &lt;0.9 %. Phylogenetic and population genetic analyses of ITS2 identified eight distinct clades (designated as Groups A to H) with moderate to high genetic heterogeneity (0.5–19.7 %). The low genetic differentiations between the geographically separated populations (pairwise <em>F_ST</em> of &lt;0.03) suggested high gene flow and lack of spatial genetic structuring. Molecular clock analysis of the ITS2 phylogeny traced the evolutionary history of <em>N. navis-varingica</em> to the Eocene Epoch, and the split between clades likely occurred from the mid-Miocene to Pleistocene Epochs (10.8–1.2 Ma). The population dispersal in the WP were likely influenced by historical events like the Quarternary glacial cycles during the period, contributing to its homogenous distributions in the region.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"141 ","pages":"Article 102769"},"PeriodicalIF":5.5,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microcystins bioaccumulate but do not biomagnify in an experimental aquatic food chain","authors":"Dani Glidewell,&nbsp;Jessica E. Beyer,&nbsp;K. David Hambright","doi":"10.1016/j.hal.2024.102768","DOIUrl":"10.1016/j.hal.2024.102768","url":null,"abstract":"<div><div>Microcystins—common hepatotoxins produced by cyanobacteria—have been detected in a wide range of organisms, though research examining the trophic transfer of microcystins and whether microcystins bioaccumulate or biomagnify in food webs has generated contradictory results. Here, we explored the trophic transfer of microcystins from the herbivorous water flea, <em>Daphnia pulex</em>, to the predatory larvae of a damselfly, <em>Enallagma</em> sp. We tested the hypotheses that microcystins transfer from the tissue of herbivorus zooplankton to that of predatory invertebrates and that these toxins biomagnify across trophic levels. We also assessed the relative contribution of toxin transfer from the gut and tissue of <em>Daphnia pulex</em> to <em>Enallagma</em> sp. We found that microcystins are effectively sequestered in the tissue of <em>Daphnia pulex</em>, and that these sequestered toxins are then transferred to the tissue of <em>Enallagma</em> sp. The contribution of gut contents to toxin transfer was negligible. Contrary to the pattern predicted by biomagnification, we found that the concentration of microcystins decreased with increasing trophic levels. Our results support the hypothesis that microcystins can be transferred trophically, but do not support the hypothesis that microcystins biomagnify from lower to higher trophic levels. Conversly, we observe biodilution in this system. These results have consequences for the impact of microcystins across trophic levels in a changing world with increasing intensity and duration of harmful algal blooms.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"141 ","pages":"Article 102768"},"PeriodicalIF":5.5,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gonyaulax montresoriae sp. nov. (Dinophyceae) from the Adriatic Sea produces predominantly yessotoxin","authors":"Shuning Huang ,&nbsp;Kenneth Neil Mertens ,&nbsp;Amélie Derrien ,&nbsp;Ophélie David ,&nbsp;Hyeon Ho Shin ,&nbsp;Zhun Li ,&nbsp;Xiuyun Cao ,&nbsp;Marina Cabrini ,&nbsp;Daniela Klisarova ,&nbsp;Haifeng Gu","doi":"10.1016/j.hal.2024.102761","DOIUrl":"10.1016/j.hal.2024.102761","url":null,"abstract":"<div><div>Yessotoxin is one of the shellfish toxins leading to mussel farm closures in the Adriatic Sea of Italy. Two putative <em>Gonyaulax spinifera</em> strains GSA0501 and GSA0602 are known as yessotoxins producers, but their identities have remained elusive since 2005. To address this gap, we established five <em>Gonyaulax</em> strains by incubating sediments from the Adriatic Sea and subsequently isolating single cells. Both cyst and theca morphology were examined using light and scanning electron microscopy. In addition, LSU and/or SSU rRNA gene sequences were obtained for all strains. Two strains produce cysts resembling <em>Spiniferites mirabilis</em> and one strain was related to <em>S. scabratus.</em> The other two strains are described as <em>Gonyaulax montresoriae</em> sp. nov., characterized by a high cingular displacement and overhang, along with two unequal antapical spines. Cysts of <em>G. montresoriae</em> are pear-shaped, showing a smooth surface and exclusively gonal processes with perforations at the base, the latter similar to <em>S. lazus</em>. LSU rRNA gene sequence comparison suggests that the <em>G. spinifera</em> strain GSA0501 isolated from the Adriatic Sea in 2005 should also be identified as <em>G. montresoriae.</em> Maximum likelihood and Bayesian inference analyses based on LSU and SSU rRNA gene sequences reveal that <em>G. montresoriae</em> is monophyletic, and close to several toxic strains of presumable <em>Gonyaulax spinifera</em> from the Adriatic Sea and New Zealand, whose taxonomic positions are uncertain. One strain of <em>G. montresoriae</em> was examined for yessotoxin production using LC-MS/MS, and found to produce predominantly yessotoxin at a concentration of 3.0 pg cell^-1. Our results highlight the rich diversity and risks associated with <em>Gonyaulax</em> species in the Mediterranean Sea.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"141 ","pages":"Article 102761"},"PeriodicalIF":5.5,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142721836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of nitrate and salinity on growth and toxin production of Prymnesium parvum","authors":"Wenhui Yan ,&nbsp;Guixiang Wang ,&nbsp;Ying Ji ,&nbsp;Jiangbing Qiu ,&nbsp;Chengxu Zhou ,&nbsp;Aifeng Li","doi":"10.1016/j.hal.2024.102760","DOIUrl":"10.1016/j.hal.2024.102760","url":null,"abstract":"<div><div>Fish-killing events caused by haptophyte <em>Prymnesium parvum</em> have been reported in aquatic environments worldwide. This haptophyte could produce diverse prymnesins (PRMs) that harm to aquatic organisms like fishes. In this study, the components of prymnesins in the strain of <em>P. parvum</em> (NMBjih029) isolated from the coast of Ningbo city, China, were elucidated by a high-resolution mass spectrometer (HRMS), and the influence of nitrate levels and salinity on growth and toxin production of <em>P. parvum</em> were also explored. Results showed that the <em>P. parvum</em> produced C-type prymnesins with structure variations in saturation, chlorination, and sugar modifications. The growth and toxin production were significantly affected by nitrate levels in the batch cultures. At the lowest level of nitrate (N:P = 4:1), growth of <em>P. parvum</em> was inhibited but toxin quotas per cell increased up to approximately 4 times of that in control group (N:P = 16:1) during the exponential growth stage. Growth of <em>P. parvum</em> was not obviously affected by different salinities, but the biosynthesis of prymnesins increased with decreasing salinity from 32 to 14 in the culture media. The proportion of high chlorination of prymnesins (tetrachloride) increased in <em>P. parvum</em> under nitrogen limitation stress and low salinity. And the toxin quotas per cell also markedly increased with the extension of culture period in <em>P. parvum</em> under nitrogen limitation and different salinity conditions. This study provides some important cues for toxin profile and environmental impacts on the biosynthesis of prymnesins in the strain of <em>P. parvum</em> isolated from Chinese aquatic environments.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"140 ","pages":"Article 102760"},"PeriodicalIF":5.5,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Species and genetic diversity of notorious dinoflagellates Pfiesteria piscicida, Luciella masanensis, and relatives in marine sediments of China","authors":"Zhe Tao ,&nbsp;Xiaohan Liu ,&nbsp;Xiaoying Song ,&nbsp;Yunyan Deng ,&nbsp;Lixia Shang ,&nbsp;Zhaoyang Chai ,&nbsp;Zhangxi Hu ,&nbsp;Yuyang Liu ,&nbsp;Ying Zhong Tang","doi":"10.1016/j.hal.2024.102746","DOIUrl":"10.1016/j.hal.2024.102746","url":null,"abstract":"<div><div>The dinoflagellate genus <em>Pfiesteria</em>, encompassing <em>Pfiesteria piscicida</em> and <em>P. shumwayae</em>, became a hot topic in HABs research in the early 2000s due to numerous but controversial reports regarding life cycle and toxicity. While <em>Pfiesteria</em> presence has been reported from all continents, surprisingly, there has been no documented presence in China to date. Here, we report our findings on the presence, species, and genetic diversity of <em>Pfiesteria</em> and its phylogenetic relatives (particularly <em>Luciella masanensis</em>) using a combined approach. First, we demonstrated the presence of <em>P. piscicida</em> and <em>L. masanensis</em> using metabarcoding analysis of &gt;320 sediment samples. <em>Pfiesteria piscicida</em> was identified in 32 sampling sites across all four seas of China, with rDNA sequences exhibiting considerable differences from the type strain (up to 3.83 %), while <em>Luciella masanensis</em> presented in 212 sites from all four seas and included only ribotypes 1 and 3 among the four known ribotypes. Second, based on the metabarcoding detections, our application of FISH with species-specific probes and subsequent single-cyst PCR sequencing to the “positive” sediments confirmed, both morphologically and molecularly, the existence of <em>P. piscicida</em> and <em>L. masanensis</em> cysts in the sediments. Finally, individual cysts were isolated using the sodium polytungstate protocol and sequenced targeting 28S rDNA D1–D6 domains. Phylogenetic analysis revealed that 35 resting cysts were relatives of <em>Pfiesteria</em>, likely belonging to either new species or novel genera and family because they formed at least two distinct clades in the phylogenetic tree. <em>Pfiesteria shumwayae</em> was not detected from any sample, suggesting its absence in Chinese waters. We believe this work provides important factual basis for the global biogeography of these species and future HABs monitoring of in China.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"140 ","pages":"Article 102746"},"PeriodicalIF":5.5,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular investigation of harmful cyanobacteria reveals hidden risks and niche partitioning in Kenyan Lakes","authors":"Brittany N. Zepernick ,&nbsp;Lauren N. Hart ,&nbsp;Emily E. Chase ,&nbsp;Kaela E. Natwora ,&nbsp;Julia A. Obuya ,&nbsp;Mark Olokotum ,&nbsp;Katelyn A. Houghton ,&nbsp;E. Anders Kiledal","doi":"10.1016/j.hal.2024.102757","DOIUrl":"10.1016/j.hal.2024.102757","url":null,"abstract":"<div><div>Despite the global expansion of cyanobacterial harmful algal blooms (cHABs), research is biased to temperate systems within the global north, such as the Laurentian Great Lakes. This lack of diversity represents a significant gap in the field and jeopardizes the health of those who reside along at-risk watersheds in the global south. The African Great Lake, Lake Victoria, is understudied despite serving as the second largest lake by surface area and demonstrating year-round cHABs. Here, we address this knowledge gap by performing a molecular survey of cHAB communities in three anthropogenically and ecologically important freshwater systems of Victoria's Kenyan watershed: Winam Gulf (Lake Victoria), Lake Simbi and Lake Naivasha. We identified a bloom of non-toxic <em>Dolichospermum</em> and toxic <em>Microcystis</em> in the Winam Gulf, with data suggesting sulfur limitation shapes competition dynamics between these two bloom-formers. Though we did not detect a bloom in Naivasha, it contained the largest diversity of cHAB genera amongst the three lakes. In turn, our results indicated methane metabolism may allow non-toxic picoplankton to outcompete cHAB genera, while suggesting <em>Synechococcus</em> spp. serves as a methane source and sink in this system. Lake Simbi exhibited a non-toxic <em>Limnospira</em> bloom at the time of sampling with very low abundances of cHAB genera present. Subsequently, these results were employed to design a cHAB screening and risk assessment framework for local stakeholders. Cumulatively, this work serves to increase cHAB research efforts on the international scale while serving as an impetus for cHAB monitoring on the local scale.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"140 ","pages":"Article 102757"},"PeriodicalIF":5.5,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of temperature, salinity and CO2 concentration on growth and toxin production of the harmful algal bloom species Alexandrium pseudogonyaulax (Dinophyceae) from the Danish Limfjord","authors":"Simon Tulatz ,&nbsp;Bernd Krock ,&nbsp;Urban Tillmann ,&nbsp;Cédric Leo Meunier","doi":"10.1016/j.hal.2024.102756","DOIUrl":"10.1016/j.hal.2024.102756","url":null,"abstract":"<div><div>The marine dinoflagellate <em>Alexandrium pseudogonyaulax</em> is a widely distributed Harmful Algal Bloom (HAB) species that produces the macrocyclic polyketide goniodomin A (GDA). Occurrences in northern European waters are increasing and a spreading of the species along a salinity gradient into the Baltic Sea has been observed. As GDA is suspected to lead to invertebrate mortality, the spreading is of concern for the environment and possibly human health. In order to assess the potential of <em>A. pseudogonyaulax</em> to adapt to the environmental conditions in the Baltic Sea and the risk of future harmful blooms of that species, we quantified the influence of bottom-up factors on the growth and toxin content of three strains of <em>A. pseudogonyaulax</em> from the Danish Limfjord. Specifically, we exposed these strains to salinities ranging from 5 to 50, temperatures in the range of 10 – 30 °C and to three different CO₂ concentrations of 250, 400 and 1000 µatm. All strains tolerated a broad range of salinities and temperatures, resulting in positive growth rates ranging from 0.06 to 0.33 d^-1 between temperatures of 12 and 27 °C and between salinities of 10 and 40. The highest cell quotas of GDA were measured at low temperatures. For two strains, GDA amounts were almost unaffected by salinity, while the cell quota of the third strain decreased about 20-fold when salinity increased above 30. Different CO₂ concentrations had no effect on growth or GDA production. In summary, these findings show a high ecological tolerance towards a wide range of temperatures and salinities of the Limfjord population of <em>A. pseudogonyaulax</em>, together with distinct intraspecific physiological differences within the population. Our results also suggest that a further spreading into the Baltic Sea might be possible.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"140 ","pages":"Article 102756"},"PeriodicalIF":5.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}