Harmful Algae最新文献

{"title":"Unprecedented toxic blooms of Microcystis spp. in 2019 in the Chowan River, North Carolina","authors":"Emily Pierce ,&nbsp;Marco Valera ,&nbsp;Mark Vander Borgh ,&nbsp;Daniel Wiltsie ,&nbsp;Elizabeth Fensin ,&nbsp;Charlton Godwin ,&nbsp;Jill Paxson ,&nbsp;Gloria Putnam ,&nbsp;Colleen Karl ,&nbsp;Blake Schaeffer ,&nbsp;Astrid Schnetzer","doi":"10.1016/j.hal.2024.102747","DOIUrl":"10.1016/j.hal.2024.102747","url":null,"abstract":"<div><div>The Chowan River flows from southern Virginia through northeastern North Carolina and into the Albemarle Sound, a part of the second largest U.S. estuary. The Chowan, which serves as an important recreational area and provides critical nursery habitat for multiple vulnerable species, has garnered much attention in recent years due to recurrent cyanobacterial harmful algal blooms (cHABs) associated with microcystins (MCs). Here we document unprecedented toxic blooms of <em>Microcystis</em> spp. during summer and fall of 2019 with MC concentrations two to three orders above the recreational guidelines of the Environmental Protection Agency (EPA, 2019). Based on 16S sequencing results in this study and previously published reports, the genus <em>Microcystis</em> emerged as a primary concern within the region. Shifts in assemblage composition, including relative abundance of <em>Microcystis</em> spp. and contributions from potential MC-degraders, linked to overall toxin concentrations and bloom stage. Congeners of varying toxicity, mainly MC-RR and MC-LR, were the most prevalent, corroborating that congeners other than MC-LR should be considered as health risk guidelines are developed. Downstream toxin transport was indicated based on changes in accumulated dissolved MC within the western Albemarle Sound which matched toxin dynamics in the Chowan River. This study provides important novel data on bacterial community composition, MC dynamics, and spatial connectivity for the Chowan River region that can aid monitoring approaches and management strategies for the protection of public health along the Chowan River and within the western Albemarle Sound.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"140 ","pages":"Article 102747"},"PeriodicalIF":5.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700354","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":"Perturbations in a pelagic food web during the NE pacific large marine heatwave and persistent harmful diatom blooms","authors":"Rocio I. Ruiz-Cooley ,&nbsp;Clarissa Anderson ,&nbsp;Raphael Kudela ,&nbsp;Robin Dunkin ,&nbsp;John Field","doi":"10.1016/j.hal.2024.102743","DOIUrl":"10.1016/j.hal.2024.102743","url":null,"abstract":"<div><div>Unprecedented warm ocean conditions, driven by the Large Marine Heatwave (LMH) and the 2015–16 El Niño in the Northeast Pacific favored pervasive toxigenic <em>Pseudo-nitzschia</em> spp. blooms that caused widespread ecological impacts, but little is known about the magnitude to which marine food webs were altered. Here, we assessed the trophic transfer of domoic acid (DA; a neurotoxin) and changes in trophic position from multiple key species during the peak of the LMH and El Niño in 2015 in comparison with 2018, a reference non-anomalous warm year. DA and amino acid nitrogen isotopes (δ¹⁵N _AAs) were quantified using liquid and gas chromatography mass spectrometry, respectively. Our integrative approach revealed extremely high levels of DA in anchovy viscera (&gt;3000 μg/g) with contrasting baseline values (δ¹⁵N _Phe) for southern California fish. These results together with data from northern CA revealed an unforeseen latitudinal isotopic variation in key DA vectors along California, possibly driven by anomalous restructuring of water masses. At the regional level, the observed cross-shore differences in baseline isotope values and DA toxicity suggest distinct pathways for DA trophic transfer for nearshore vs. offshore sites. Given the high levels of environmental disturbance during the LMH and persistence of toxigenic <em>P. australis</em> blooms, our resultant higher trophic position proxies in 2015 compared to 2018 were particularly unexpected. Such results highlight complex trophic interactions, where the trophic status of some species increased while others decreased in response to changes in net primary productivity, and biodiversity, and abundance of forage species. Our study demonstrates the use of δ¹⁵N AAs to identify pathways of N and DA trophic transfer and to quantify shifts in animal trophic position, a critical facet of understanding the response of food webs to climate change and DA production.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"140 ","pages":"Article 102743"},"PeriodicalIF":5.5,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700353","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":"Corrigendum to “Defense against Paramecium predation via long filament morphology favors the survival of Raphidiopsis raciborskii populations” [Harmful Algae 137 (2024) 102678]","authors":"Zeshuang Wang ,&nbsp;Xiaoli Huang ,&nbsp;Yangyang Wu ,&nbsp;Xiang Hu ,&nbsp;Qihang Zhao ,&nbsp;Jun Zuo ,&nbsp;Peng Xiao ,&nbsp;Yao Cheng ,&nbsp;He Zhang ,&nbsp;Renhui Li","doi":"10.1016/j.hal.2024.102733","DOIUrl":"10.1016/j.hal.2024.102733","url":null,"abstract":"","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"139 ","pages":"Article 102733"},"PeriodicalIF":5.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142684068","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":"Response of heterocyst differentiation of Dolichospermum to different forms of nitrogen deficiency","authors":"Zichen Liu ,&nbsp;Fazhi Xie ,&nbsp;Liya Wang ,&nbsp;Li Yu ,&nbsp;Xiaoli Shi ,&nbsp;Zhen Yang ,&nbsp;Min Zhang","doi":"10.1016/j.hal.2024.102742","DOIUrl":"10.1016/j.hal.2024.102742","url":null,"abstract":"<div><div>In recent years, initiatives aimed at mitigating eutrophication have successfully reduced nitrogen and phosphorus concentrations in numerous lakes across China. Notably, the management of total nitrogen levels has prompted a shift in the dominant genera responsible for harmful algal blooms. Among these, <em>Dolichospermum</em>, a typical diazotrophic cyanobacterium, exhibits the ability to differentiate heterocysts for atmospheric N₂ fixation under nitrogen-limited conditions. However, the underlying mechanisms driving heterocyst differentiation in response to the absence of specific nitrogen compounds remain poorly understood. This study analyzed the driving factors influencing heterocyst frequency using field data from Lake Chaohu collected between January and June 2022. Furthermore, an experiment was conducted utilizing NH₄Cl, NaNO₃ and urea as nitrogen sources, with specific nitrogen deficiencies created to investigate the response mechanisms of <em>Dolichospermum</em> under these conditions. The results indicated significant monthly variations in heterocyst frequency in Lake Chaohu, which were associated with the interaction of multiple driving factors. Nutrient changes emerged as the most intuitive driving factor, with heterocyst frequency showing a significant negative correlation with total nitrogen and dissolved total nitrogen levels. Experimental results demonstrated that the absence of NO₃<img>N promoted both the biomass and heterocyst frequency of <em>Dolichospermum</em>. When NH_4<img>N was limited, the proliferation of <em>Dolichospermum</em> was inhibited, leading to an extended period of heterocyst development. Although a lack of urea eventually increased heterocyst frequency in <em>Dolichospermum</em>, there was no significant increase in biomass. The concentrations of the three nitrogen sources exhibited a negative correlation with heterocyst differentiation, with the effects of NO₃<img>N and urea deficiency on heterocyst differentiation being significantly stronger than those of NH₄<img>N. Moreover, heterocyst differentiation frequency was positively correlated with photosynthetic efficiency, which indicated that the acquisition and distribution of photosynthetic energy between heterocysts and vegetative cells also influence the differentiation process of heterocysts to some extent. The findings highlight the differing responses of heterocyst differentiation to various forms of nitrogen, emphasizing the importance of prioritizing NH₄<img>N removal in nutrient control. However, further research is needed to determine the key threshold concentrations of different nitrogen sources that trigger heterocyst differentiation.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"139 ","pages":"Article 102742"},"PeriodicalIF":5.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571861","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":"Identification of novel microcystins in algal extracts by a liquid chromatography–high-resolution mass spectrometry data analysis pipeline","authors":"Kirsten A. Cottrill ,&nbsp;Christopher O. Miles ,&nbsp;Logan C. Krajewski ,&nbsp;Brady R. Cunningham ,&nbsp;William Bragg ,&nbsp;Noelani R. Boise ,&nbsp;Kristin D. Victry ,&nbsp;David S. Wunschel ,&nbsp;Karen L. Wahl ,&nbsp;Elizabeth I. Hamelin","doi":"10.1016/j.hal.2024.102739","DOIUrl":"10.1016/j.hal.2024.102739","url":null,"abstract":"<div><h3>Background</h3><div>Microcystins are an emergent public health problem. These toxins are secondary metabolites of harmful cyanobacterial blooms, with blooms becoming more prevalent with eutrophication of water. Exposure to microcystins can result in sickness, liver damage, and even death. Over 300 microcystins have been identified to date, with differences in toxicity based on the specific amino acid composition. Because of this diversity in microcystins, as well as the likelihood of detecting as yet undiscovered microcystins, it is vital to establish a methodological workflow to identify any microcystin in a complex sample, regardless of the availability of a reference standard. Additionally, ascribing varying levels of confidence to these identifications is critical to effectively communicate discoveries.</div></div><div><h3>Methods</h3><div>A liquid-chromatography–high-resolution mass spectrometry method was utilized to identify microcystins present in cyanobacterial extracts from a strain of <em>Microcystis aeruginosa</em> and an <em>Aphanizomenon</em> sp. First, microcystin congeners with available standards were identified in the cyanobacterial extract. These known-unknown microcystins were considered to have the highest confidence identifications due to availability of accurate masses, retention times, and library spectra for comparison. Utilizing the spectra of these microcystins, relatively high-abundance diagnostic product-ions were identified and employed to screen the data for additional candidate microcystins. Microcystins without a standard that had an exact mass matching a microcystin published in CyanoMetDB were considered semi-known-unknown microcystins. The remaining microcystins were considered unknown-unknown microcystins. The identities of the microcystins determined herein were additionally supported by product-ion analysis, thiol reactivity, esterification reactions, neutral loss analysis, and literature contextualization.</div></div><div><h3>Results</h3><div>In total, utilizing the systematic workflow presented herein, 23 microcystins were identified in the <em>M. aeruginosa</em> culture, including two not published previously: [<span>d</span>-Asp³]MC-LCit and the incompletely identified MC-L(C₇H₁₁NO₃).</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"139 ","pages":"Article 102739"},"PeriodicalIF":5.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586526","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":"Connectivity of toxigenic Pseudo-nitzschia species assemblages between the Northeast U.S. continental shelf and an adjacent estuary","authors":"Katherine M. Roche ,&nbsp;Isabella N. Church ,&nbsp;Alexa R. Sterling ,&nbsp;Tatiana A. Rynearson ,&nbsp;Matthew J. Bertin ,&nbsp;Andrew M. Kim ,&nbsp;Riley D. Kirk ,&nbsp;Bethany D. Jenkins","doi":"10.1016/j.hal.2024.102738","DOIUrl":"10.1016/j.hal.2024.102738","url":null,"abstract":"<div><div><em>Pseudo-nitzschia</em> harmful algal blooms have recently caused elevated domoic acid in coastal environments of the Northeast United States. In 2017, the toxigenic species <em>P. australis</em> was observed in Narragansett Bay, Rhode Island, a temperate estuarine ecosystem, for the first time since 2009 when DNA monitoring for <em>Pseudo-nitzschia</em> species began. This highly toxic species likely contributed to toxin-related shellfish harvest closures and is hypothesized to have been introduced by an offshore source. Little is known about offshore <em>Pseudo-nitzschia</em> spp. populations in the Northeast Continental Shelf marine ecosystem or how often toxigenic species enter Narragansett Bay through physical processes. Here, we collected filtered biomass samples from multiple time series sites within Narragansett Bay and along the Northeast U.S. Shelf Long-Term Ecological Research transect in winter and summer to investigate the frequency and seasonality of potential <em>Pseudo-nitzschia</em> spp. inflow from the continental shelf to the estuary. Species were taxonomically identified using DNA sequencing of the ITS1 region and domoic acid concentrations were quantified by liquid chromatography with tandem mass spectrometry and multiple reaction monitoring. During six years of sampling, <em>Pseudo-nitzschia</em> species assemblages were more similar between Narragansett Bay and the Northeast shelf in winter than summer, suggesting greater ecosystem connectivity in winter. These winter assemblages were often accompanied by higher domoic acid. Several <em>Pseudo-nitzschia</em> species co-occurred most often with domoic acid and were likely responsible for toxin production in this region, including <em>P. pungens</em> var<em>. pungens, P. multiseries, P. calliantha, P. plurisecta, P. australis</em>, and <em>P. fraudulenta</em>. Domoic acid was detected during periods of relatively low macronutrient concentrations in both seasons, warmer sea surface temperatures in winter, and colder temperatures in summer within this dataset. This study represents some of the first domoic acid measurements on the offshore Northeast U.S. Continental Shelf, a region that supplies water to other coastal environments and could seed future harmful algal blooms. The elevated domoic acid and frequency of hypothesized inflow of toxigenic <em>Pseudo-nitzschia</em> spp. from the Northeast continental shelf to Narragansett Bay in winter indicate the need to monitor coastal and offshore environments for toxins and harmful algal bloom taxa during colder months.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"139 ","pages":"Article 102738"},"PeriodicalIF":5.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571860","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":"Light-driven differences in bacterial networks and organic matter decomposition: Insights from an analysis of the harmful cyanobacterium Microcystis aeruginosa PCC 7806","authors":"Yang Liu ,&nbsp;Xiding Wang ,&nbsp;Xudong Liu ,&nbsp;Fangru Nan ,&nbsp;Jie Wang ,&nbsp;Qi Liu ,&nbsp;Junping Lv ,&nbsp;Jia Feng ,&nbsp;Shulian Xie","doi":"10.1016/j.hal.2024.102740","DOIUrl":"10.1016/j.hal.2024.102740","url":null,"abstract":"<div><div>Freshwater systems are critical yet often underestimated components of global carbon cycling, functioning both as carbon sinks and sources. Cyanobacteria play a key role in this cycle by capturing atmospheric carbon dioxide through photosynthesis. The captured carbon is either released back into the atmosphere or sequestered in sediments following organismal decay. This study examines the pivotal role of cyanobacteria, specifically <em>Microcystis aeruginosa</em> PCC 7806, in the biogeochemical cycling of carbon in freshwater ecosystems, with a focus on how light influences the degradation of cyanobacteria-derived organic matter. Using a combination of 16S rDNA sequencing and excitation-emission matrix coupled with parallel factor (EEM-PARAFAC) analysis, we conducted a 50-day experiment to investigate the dynamics of dissolved organic matter (DOM) and lysate organic matter (LOM) derived from <em>M. aeruginosa</em> PCC 7806 under light and dark conditions. Our results demonstrate that light significantly impacts bacterial community composition, gene functionality, and the decomposition of organic matter. The findings emphasize the crucial role of light in facilitating microbial adaptation, stabilizing microbial networks and driving organic substrate transformation. These insights underscore the influence of light on microbial community dynamics and organic matter degradation, revealing shifts in microbial populations under varying light conditions. This suggests a strong link between photochemical processes and microbial activity, with significant ecological implications.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"139 ","pages":"Article 102740"},"PeriodicalIF":5.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142561082","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 mixotrophy on cell cycle phase duration and correlation of karlotoxin synthesis with light and G1 phase in Karlodinium veneficum","authors":"Erik L.J.E. Broemsen ,&nbsp;Jens Wira ,&nbsp;Allen R. Place ,&nbsp;Matthew W. Parrow","doi":"10.1016/j.hal.2024.102741","DOIUrl":"10.1016/j.hal.2024.102741","url":null,"abstract":"<div><div><em>Karlodinium veneficum</em> forms fish killing blooms in estuaries worldwide. The toxicity of these blooms is variable and thought to be connected to bloom stage and <em>in situ</em> growth rates. Methods for measuring <em>in situ</em> growth rates rely on the assumption that cell cycle progression is phased to the diel photocycle, which is true for phototrophically-growing <em>K. veneficum</em> cultures where G1 phase occurs during light and S and G2 + <em>M</em> phases occur during darkness. However, <em>K. veneficum</em> is a facultative mixotroph that also phagocytizes microalgal prey, and the effects of this mixotrophy on its cell cycle synchrony are unknown. Furthermore, toxicity in laboratory cultures is inversely related to growth rate and is light dependent, suggesting synchrony between the cell cycle (G1 phase) and karlotoxin synthesis. To test this, the cell cycle phase distribution and cellular toxin content for phototrophic and mixotrophic cultures of <em>K. veneficum</em> were monitored hourly for a full diel cycle. The results demonstrated that mixotrophic cultures maintained a synchronized cell cycle, despite increased growth rates. The faster growth rates were attributed to a shortened duration of G1 phase in mixotrophic cultures compared to phototrophic cultures (30.8 ± 9.2 h vs 69.4 ± 21.5 h, respectively). Meanwhile, toxin production was observed only during light hours, consistent with synthesis initiating with the photorespiratory byproduct glycolate. Cellular toxin content had a significant positive correlation with the percentage of G1 phase cells and a significant negative correlation with the percentage of S phase cells. These results indicate a clear role in mixotrophy increasing growth rates of <em>K. veneficum</em> and of the diel photocycle in synchronizing the cell and karlotoxin synthetic cycles.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"140 ","pages":"Article 102741"},"PeriodicalIF":5.5,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661257","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":"Discovery of novel and known viruses associated with toxigenic and non-toxigenic bloom forming diatoms from the Northern Adriatic Sea","authors":"Timotej Turk Dermastia ,&nbsp;Denis Kutnjak ,&nbsp;Ion Gutierrez-Aguirre ,&nbsp;Corina P.D. Brussaard ,&nbsp;Katarina Bačnik","doi":"10.1016/j.hal.2024.102737","DOIUrl":"10.1016/j.hal.2024.102737","url":null,"abstract":"<div><div>Algal blooms impact trophic interactions, community structure and element fluxes. Despite playing an important role in the demise of phytoplankton blooms, only few viruses infecting diatoms have been cultured. <em>Pseudo-nitzschia</em> is a widespread diatom genus that commonly blooms in coastal waters and contains toxin-producing species. This study describes the characterization of a novel virus infecting the toxigenic species <em>Pseudo-nitzschia galaxiae</em> isolated from the northern Adriatic Sea. The ssRNA virus PnGalRNAV has 29.5 nm ± 1.2 nm icosahedral virions and a genome size of 8.8 kb. It belongs to the picorna-like <em>Marnaviridae</em> family and shows high specificity for <em>P. galaxiae</em> infecting two genetically and morphologically distinct strains. We found two genetically distinct types of this virus and screening of the global virome database revealed matching sequences from the Mediterranean region and China, suggesting its global distribution. Another virus of similar shape and size infecting <em>Pseudo-nitzschia calliantha</em> was found, but its genome could not be determined. In addition, we have obtained and characterized a new virus that infects <em>Chaetoceros tenuissimus</em>. The replicase protein of this virus is very similar to the previously described ChTenDNAV type-II virus, but it has a unique genome and infection pattern. Our study is an important contribution to the collective diatom virus culture collection and will allow further investigation into how these viruses control diatom bloom termination, carbon export and toxin release in the case of <em>Pseudo-nitzschia</em>.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"139 ","pages":"Article 102737"},"PeriodicalIF":5.5,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533604","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":"Accumulation and depuration of 4,5-dihydro-KmTx2 from Karlodinium veneficum in the bivalves, Mercenaria mercenaria and Sinonovacula constricta","authors":"Yanrong Li ,&nbsp;Rong Chen ,&nbsp;Zhujun Zhu ,&nbsp;Tong Mu ,&nbsp;Zhaoshou Ran ,&nbsp;Jilin Xu ,&nbsp;Chengxu Zhou ,&nbsp;Xiaojun Yan","doi":"10.1016/j.hal.2024.102736","DOIUrl":"10.1016/j.hal.2024.102736","url":null,"abstract":"<div><div>Bivalves (e.g., clams, oysters, mussels, scallops) are a significant part of the global diet and are harvested for their nutritional value, but as filter feeders they are susceptible to the accumulation of toxins produced by certain species of phytoplankton. Karlotoxins (KmTxs) are a class of amphidinol-like compounds with hemolytic, ichthyotoxic, and cytotoxic properties that have been associated with harmful algal blooms, and the dinoflagellate <em>Karlodinium veneficum</em> uses KmTxs to facilitate prey capture and deter grazing by other organisms. In this work, we examined the accumulation and depuration of 4,5-dihydro-KmTx2, a karlotoxin previously isolated from <em>K. veneficum</em>, in two bivalves with different life habits, i.e., <em>Sinonovacula constricta</em> Lamarck and <em>Mercenaria mercenaria</em> Linnaeus. After both bivalves received <em>K. veneficum</em> GM5 in their feed for a long period of 10 days, 4,5-dihydro-KmTx2 was accumulated considerably in the visceral mass, but there was almost no toxin accumulation in the muscle. The accumulation was more severe for <em>M. mercenaria</em> than <em>S. constricta</em>. The toxin was cleared almost completely from the bivalves 5 days after <em>K. veneficum</em> GM5 was removed from the feed. For both bivalves, the bait microalgae <em>I. galbana</em> slowed both the accumulation and the depuration of the toxin.</div></div>","PeriodicalId":12897,"journal":{"name":"Harmful Algae","volume":"139 ","pages":"Article 102736"},"PeriodicalIF":5.5,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533010","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}