Advances in Oceanography and Limnology最新文献

{"title":"Biodiversity ecosystem functioning research in freshwater phytoplankton: A comprehensive review of trait-based studies","authors":"P. Venail","doi":"10.4081/AIOL.2017.7207","DOIUrl":"https://doi.org/10.4081/AIOL.2017.7207","url":null,"abstract":"In an effort to reach a clearer mechanistic understanding of the influence of biological diversity on ecosystem functioning, research in the field is increasingly applying a trait-based approach. In this comprehensive review, I searched for and analyzed studies that focused on the relationship between biodiversity and ecosystem functioning (BEF) using a trait-based approach in freshwater phytoplankton from lentic systems (lakes, ponds, reservoirs). I found that this type of studies is very rare and included a plethora of traits, diversity metrics, statistical analyses and study locations that contributed to the high variability in the results they obtained. Overall, trait-based diversity is not a very good predictor of ecosystem functioning in freshwater lentic ecosystems. Null relationships between trait-based diversity and ecosystem functioning in freshwater lentic systems were the more frequent outcome. When significant, the amount of variation in ecosystem functioning explained by trait-based diversity was small. Still, trait-based research remains a promising approach to increase the mechanistic understanding of BEF relationships. For this purpose, studies directly testing the underlying mechanistic rationale, exploring diversity effects on the temporal stability of ecosystem functions, including multiple functions at a time, focusing more in cell size and shape and confirming the relative importance of individual trait variation for ecosystem functioning are needed.","PeriodicalId":37306,"journal":{"name":"Advances in Oceanography and Limnology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4081/AIOL.2017.7207","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45320402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In memoriam of Peppe Morabito","authors":"M. Manca","doi":"10.4081/AIOL.2017.7209","DOIUrl":"https://doi.org/10.4081/AIOL.2017.7209","url":null,"abstract":"“Lightly we passed on Earth” is the title of a novel by Sergio Atzeni, published in 1996, one year after his untimely death by drowning in the Tyrrhenian sea. The author is referring to the levity of water. «Lightly we passed on Earth”…. “like the water that flows, jumps from the hollow spring, winds between mosses and ferns up to the roots of almond and cork trees or rolls over the stones from mountains and hills toward the plain, from stream to river, slowing down on the way to the swamps and the sea, transmuted by the sun in steam, in clouds moved by the wind, and in blissful rain…”","PeriodicalId":37306,"journal":{"name":"Advances in Oceanography and Limnology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4081/AIOL.2017.7209","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45060269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Foreword to the Themed Issue “Cyanobacteria”","authors":"T. Kaloudis, J. Meriluoto, L. Bláha","doi":"10.4081/AIOL.2017.6674","DOIUrl":"https://doi.org/10.4081/AIOL.2017.6674","url":null,"abstract":"COST (European Cooperation in Science and Technology) is a pan-European intergovernmental framework. Its mission is to enable break-through scientific and technological developments leading to new concepts and products and thereby contribute to strengthening Europe’s research and innovation capacities. It allows researchers, engineers and scholars to jointly develop their own ideas and take new initiatives across all fields of science and technology, while promoting multi- and interdisciplinary approaches. COST aims at fostering a better integration of less research-intensive countries to the knowledge hubs of the European Research Area. The COST Association, an International Not-for-profit Association under Belgian Law, integrates all management, governing and administrative functions necessary for the operation of the framework. The COST Association has currently 36 Member Countries. www.cost.eu","PeriodicalId":37306,"journal":{"name":"Advances in Oceanography and Limnology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4081/AIOL.2017.6674","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43892340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cyanobacteria and microcystin contamination in untreated and treated drinking water in Ghana","authors":"G. Addico, J. Hardege, J. Kohoutek, K. deGraft-Johnson, P. Babica","doi":"10.4081/AIOL.2017.6323","DOIUrl":"https://doi.org/10.4081/AIOL.2017.6323","url":null,"abstract":"Although cyanobacterial blooms and cyanotoxins represent a worldwide-occurring phenomenon, there are large differences among different countries in cyanotoxin-related human health risk assessment, management practices and policies. While national standards, guideline values and detailed regulatory frameworks for effective management of cyanotoxin risks have been implemented in many industrialized countries, the extent of cyanobacteria occurrence and cyanotoxin contamination in certain geographical regions is under-reported and not very well understood. Such regions include major parts of tropical West and Central Africa, a region constisting of more than 25 countries occupying an area of 12 million km 2 , with a total population of 500 milion people. Only few studies focusing on cyanotoxin occurrence in this region have been published so far, and reports dealing specifically with cyanotoxin contamination in drinking water are extremely scarce. In this study, we report seasonal data on cyanobacteria and microcystin (MC) contamination in drinking water reservoirs and adjacent treatment plants located in Ghana, West Africa. During January-June 2005, concentrations of MCs were monitored in four treatment plants supplying drinking water to major metropolitan areas in Ghana: the treatment plants Barekese and Owabi, which serve Kumasi Metropolitan Area, and the plants Kpong and Weija, providing water for Accra-Tema Metropolitan Area. HPLC analyses showed that 65% samples of raw water at the intake of the treatment plants contained intracellular MCs (maximal detected concentration was 8.73 µg L -1 ), whereas dissolved toxins were detected in 33% of the samples. Significant reduction of cyanobacterial cell counts and MC concentrations was achieved during the entire monitoring period by the applied conventional water treatment methods (alum flocculation, sedimentation, rapid sand filtration and chlorination), and MC concentration in the final treated water never exceeded 1 µg L -1 (WHO guideline limit for MCs in drinking water). However, cyanobacterial cells (93-3,055 cell mL -1 ) were frequently found in the final treated water and intracellular MCs were detected in 17% of the samples (maximal concentration 0.61 µg L -1 ), while dissolved MCs were present in 14% of the final treated water samples (maximal concentration 0.81 µg L -1 ). It indicates a borderline efficiency of the water treatment, thus MC concentrations in drinking water might exceed the WHO guideline limit if the treatment efficiency gets compromised. In addition, MC concentrations found in the raw water intake might represent significant human health risks for people living in areas with only a limited access to the treated or underground drinking water.","PeriodicalId":37306,"journal":{"name":"Advances in Oceanography and Limnology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4081/AIOL.2017.6323","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42779221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comparative study of the metabolic profiles of common nuisance cyanobacteria in southern perialpine lakes","authors":"L. Cerasino, C. Capelli, N. Salmaso","doi":"10.4081/AIOL.2017.6381","DOIUrl":"https://doi.org/10.4081/AIOL.2017.6381","url":null,"abstract":"This work allowed the comparison of the metabolic profiles of the most important cyanobacteria species in southern perialpine lakes, namely Aphanizomenon flos-aquae , Dolichospermum lemmermannii, Microcystis aeruginosa, Planktothrix rubescens , and Tychonema bourrellyi. Monospecific cultures were obtained from samples of 3 different natural lakes (Garda, Idro, and Caldonazzo). LC-MS/MS analyses were conducted on strains. A first set of experiments was aimed at assessing the presence of the best known toxins (microcystins, nodularins, (homo)anatoxin-a, cylindrospermopsins, paralytic shellfish poisons) in the cultures. Results of this screening study revealed that M. aeruginosa and P. rubescens produced toxic peptides (microcystins), T. bourrellyi produced toxic alkaloids (anatoxin-a and possibly some paralytic shellfish toxins), Aph. flos-aquae and D. lemmermannii did not produce any of the analyzed toxins. M. aeruginosa and P. rubescens showed typical microcystin production with LR form dominant in the former, and RRdm form dominant in the latter. A second set of experiments was aimed at comparing the capability of the 5 cyanobacterial species to produce peptidic secondary metabolites. For this purpose, an untargeted peptidomic analysis was conducted on the strains. The analysis allowed revealing globally 328 metabolites, spanning in a mass range between 400 and 2000 Da. The majority of compounds with masses in the 500-1200 Da range (corresponding to the majority of peptidic secondary metabolites) resulted to be produced by M. aeruginosa and P. rubescens strains, thus indicating a higher ability of these species to produce non-ribosomal peptides compared to the others. 27 metabolites out of 328 could be putatively assigned to specific classes of compounds: microcystins, aeruginosins and anabaenopeptins were the most represented classes of compounds, and were mostly found in M. aeruginosa and P. rubescens strains.","PeriodicalId":37306,"journal":{"name":"Advances in Oceanography and Limnology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4081/AIOL.2017.6381","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41777819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular detection of hepatotoxic cyanobacteria in inland water bodies of the Marmara Region, Turkey","authors":"Latife Köker, R. Akçaalan, Meriç Albay, B. Neilan","doi":"10.4081/AIOL.2017.6394","DOIUrl":"https://doi.org/10.4081/AIOL.2017.6394","url":null,"abstract":"Blooms of cyanobacteria are an increasingly frequent phenomenon in freshwater ecosystems worldwide as a result of eutrophication. Many species can produce hepatotoxins that cause severe health hazards to humans. The aim of this study was to identify the bloom forming cyanobacteria species by molecular methods and to amplify genes responsible for hepatotoxin biosynthesis from the environmental samples and isolated strains of cyanobacteria from Kucukcekmece Lagoon, Sapanca, Iznik, Manyas and Taskisi Lakes. A total of 10 bloom samples and 11 isolated strains were examined and Microcystis spp., Planktothrix spp., Nodularia spumigena , Anabaenopsis elenkinii , Sphaerospermopsis aphanizomenoides , Cylindrospermopsis raciborskii were identified. Hepatotoxin genes were detected in 60% of the bloom samples and 45% of the strains. Two Microcystis strains were obtained from Kucukcekmece Lagoon. While the strain assigned to Microcystis flosaquae was non-toxic, Microcystis aeruginosa strain produced microcystin. According to PCR results, the M. aeruginosa and Planktothrix agardhii bloom samples of Kucukcekmece Lagoon contained the microcystin synthetase gene E (mcyE) indicative of microcystin production, however, no microcystin was detected by HPLC. The mcyE gene was also found in Microcystis wesenbergii isolated from Taskisi Lake, and in all Planktothrix rubescens bloom samples from Sapanca Lake. To our knowledge, this is the first detailed study for identifiying different toxic cyanobacteria species and their hepatotoxin production from several waterbodies in Turkey using molecular methods.","PeriodicalId":37306,"journal":{"name":"Advances in Oceanography and Limnology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4081/AIOL.2017.6394","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48185906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rare occurrence of nine Microcystis species (Chroococcales, Cyanobacteria) in a single lake (Lake Dojran, fYR Macedonia)","authors":"S. Krstic, Boris Alesovski, J. Komárek","doi":"10.4081/aiol.2017.6236","DOIUrl":"https://doi.org/10.4081/aiol.2017.6236","url":null,"abstract":"Investigations carried out on Lake Dojran, fYR Macedonia, during the spring-autumn seasons in 2015 have been focused on detecting the degree of eutrophication in the lake, successive algal flora changes in the plankton communities and eventual presence of cyanotoxins (free microcystins) in the water. The obtained results revealed a co-existence of nine Microcystis species in the lake ( M. aeruginosa, M. botrys, M. flos-aquae, M. ichthyoblabe, M. novacekii, M. protocystis, M. smithii, M. viridis and M. wesenbergii ), with domination of the pan and neo-tropical species M. protocystis , again confirmed in a European lake. Results also corroborate the necessity to change the accepted morphospecies concept into separation of Microcystis taxa as distinct species which are clearly delimited according to their constant morphological features. Toxicity analyses demand for a specific and targeted investigation, since the toxin production and presence depends on many factors, and the toxin dynamics including the highest peaks may be easily overlooked if other issues are in the focus of the performed monitoring. Detected values for free microcystins in the water reached 2.84 µg L -1 microcystin-LR equivalents.","PeriodicalId":37306,"journal":{"name":"Advances in Oceanography and Limnology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4081/aiol.2017.6236","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44319144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cyanobacterial dynamics and toxins concentrations in Lake Alto Flumendosa, Sardinia, Italy","authors":"M. Stefanelli, Simona Scardala, P. Cabras, A. Orrù, S. Vichi, E. Testai, E. Funari, M. Manganelli","doi":"10.4081/AIOL.2017.6352","DOIUrl":"https://doi.org/10.4081/AIOL.2017.6352","url":null,"abstract":"Seasonal blooms of cyanobacteria (CB) are a typical feature of Lake Alto Flumendosa (Sardinia, Italy). The waters of this lake are used for drinking water supply, for agricultural and industrial uses, and fish farming activities. Since cyanotoxins are not monitored in edible organisms, diet could be a relevant route of human exposure. CB also represent a threat for the health of wild and domestic animals that use lake water for beverage. Therefore, to characterize the CB community and assess the risk for human and animal population, CB dynamic, mcy B + fraction, and microcystins (MCs) concentration have been followed monthly for 18 months, in three stations. Results confirmed the presence of several toxigenic species. Planktothrix rubescens dominated between August 2011 and April 2012 (3.5×10 6 cells L -1 ), alternating with Woronichinia naegeliana (8×10 6 cells L -1 ) and Microcystis botrys (9×10 5 cells L -1 ). Dolichospermum planctonicum was always present at low densities (10 4 cells L -1 ). MCs were detected, at values well below the 1 µg L -1 threshold of WHO for drinking water. The molecular analysis of mcy B gene for P. rubescens indicated the presence of a persistent toxic population (average 0.45 mcy B/16S rDNA). Highly significant linear regressions were found between P. rubescens and the sum of the demethylated MC variants, and between M. botrys and the sum of MC-LR and MC-LA, also when co-occurring, suggesting that these two species were responsible for different MC patterns production. The regression lines indicated a quite stable MC cell quota. However, in some spotted samples very different values were obtained for both MC concentrations and cell quota (from 10-fold lower to 30-40-fold higher than the ‘average’) showing an unexpected significant variability in the rate of toxin production. The relatively low cell densities during the monitoring period is consistent with the low-to absent MC contamination level found in trout muscle; however, the analytical method was affected by low recovery, probably due to MC-protein binding. Our results show that, during the study period, no risk of exposure for the human and animal population occurred. However, the persistence of a complex CB community characterised by a significant toxic fraction suggests the need for periodic monitoring activity. Particularly, the hidden deep summer P. rubescens blooms, located where water is taken for drinking water supply, and M. botrys , able to produce the most toxic MC variants with high cell quota, should be kept under control. The documentation and interpretation of sudden changes in toxins concentrations deserve special attention. This is particularly relevant in proximity of fish farming plants and water catchment sites.","PeriodicalId":37306,"journal":{"name":"Advances in Oceanography and Limnology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4081/AIOL.2017.6352","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42912076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Monitoring a newly re-born patient: water quality and cyanotoxin occurrence in a reconstructed shallow Mediterranean lake","authors":"S. Gkelis, M. Panou, I. Chronis, Sevasti-Kiriaki Zervou, C. Christophoridis, Korina Manolidi, Chrysoula Ntislidou, T. Triantis, T. Kaloudis, A. Hiskia, I. Kagalou, M. Lazaridou","doi":"10.4081/AIOL.2017.6350","DOIUrl":"https://doi.org/10.4081/AIOL.2017.6350","url":null,"abstract":"Lake Karla (Central Greece) is a unique example - at European scale - of a shallow lake ecosystem that was dried in the 1960s and in 2009 started to be restored. The lake is listed in the network of the Greek protected areas as it is considered a vital aquatic ecosystem, in terms of biodiversity. It has, however, already been adversely affected by both agricultural and industrial land uses in the surrounding area, leading to eutrophication and shifting algal community towards bloom-forming toxic cyanobacterial species. After repeated heavy-blooms, cyanotoxin occurrence and mass fish kills, the local ecosystem management authority has implemented a water quality monitoring program (July 2013 - July 2015) to assess environmental pressures and the response of aquatic biota in the lake. Microscopic, immunological, and molecular techniques combined with physico-chemical parameters, complemented by liquid chromatography tandem mass spectrometry (LC-MS/MS), were used to monitor cyanobacteria blooms and the associated cyanotoxin production from three different sites in Lake Karla and from the adjacent Kalamaki Reservoir. Water quality was also assessed by the structure of benthic invertebrate community on the sediment. Cyanobacteria were the main phytoplankton component, representing more than 70% of the total phytoplankton abundance; dominant taxa belonged to Cylindrospermopsis raciborskii , Limnothrix redekei , Anabaenopsis elenkinii , and Microcystis spp. Euglenophytes ( Euglena ), diatoms ( Nitzschia ), and chlorophytes ( Scenedesmus ) were also important phytoplankton constituents. LC-MS/MS confirmed the co-occurrence of microcystins, cylindrospermopsin, saxitoxin, neo-saxitoxin and anatoxin-a. The occurrence of cyanotoxins in relation to the persistent and dominant cyanobacteria and the impact of cyanobacterial harmful algal blooms on the newly constructed lake along with the land uses and the emergent mitigation measures are discussed.","PeriodicalId":37306,"journal":{"name":"Advances in Oceanography and Limnology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4081/AIOL.2017.6350","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43803046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report of cyanobacterial paralytic shellfish toxin biosynthesis genes and paralytic shellfish toxin production in Polish freshwater lakes","authors":"H. Savela, L. Spoof, Niina Höysniemi, M. Vehniäinen, J. Mankiewicz-Boczek, T. Jurczak, M. Kokociński, J. Meriluoto","doi":"10.4081/AIOL.2017.6319","DOIUrl":"https://doi.org/10.4081/AIOL.2017.6319","url":null,"abstract":"In central and southern Europe, Aphanizomenon spp., A. gracile Lemmermann in particular, have been associated with paralytic shellfish toxin (PST) production. In western Poland, A. gracile is very common, and Cylindrospermopsis raciborskii (Woloszynska) Seenayya & Subba Raju, another potentially PST-producing species, is often found as well. To date it is, however, unknown if the cyanobacterial populations in this area harbour the genetic capability to produce PSTs, and to what extent toxin biosynthesis occurs. The objective of this study was to survey the prevalence of potentially PST-producing cyanobacteria by measuring paralytic shellfish toxin biosynthesis gene sxtB copy numbers, sxtA , sxtG and sxtS gene presence, and PST concentrations in Polish freshwater lakes. In total, 34 lakes in western Poland were sampled twice during summer 2010. The presence of PST biosynthesis genes sxtA , sxtG and sxtS was determined using conventional qualitative PCR. Quantitative PCR (qPCR) was used to measure sxtB copy numbers, and the samples were analysed for PSTs using ion-pair high performance liquid chromatography with post-column oxidation and fluorescence detection (HPLC-FLD). Cyanobacteria carrying the sxtB gene were present in 23.5% of all samples (n=16) and in 14 lakes of the studied 34. Gene copy numbers ranged from 8.2×10 4 to 5.1×10 7 sxtB copies L -1 (mean 3.8×10 6 ). The median was 4.5×10 5 sxtB gene copies L -1 and the majority of results clustered at the lower end of the sxtB qPCR linear range. In 12 out of the 16 samples positive for sxtB the gene co-occurred with the other three targeted PST biosynthesis genes sxtA , sxtG and sxtS . However, five additional samples lacked one or two of the targeted four genes. Thirteen samples contained PSTs, of which 12 samples at levels <0.072 µg L -1 , i.e. , close to or below the quantitative detection limit of the HPLC-FLD method (0.01 µg L -1 ). One sample contained 0.57 µg L -1 saxitoxin, co-occurring with all four sxt genes studied. No correlation between PST and sxt gene occurrence or copy numbers was observed. A. gracile and C. raciborskii occurred in 92% and 50% of samples, respectively, containing PSTs, sxt genes or both. In conclusion, the results confirm that potential PST producers constitute an established subpopulation of cyanobacteria in Polish freshwater lakes. However, none of the sxt genes targeted in this study could serve as a reliable marker for active PST biosynthesis.","PeriodicalId":37306,"journal":{"name":"Advances in Oceanography and Limnology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4081/AIOL.2017.6319","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43437612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}