Browsing by Subject "anatoxin"

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  • Osterholm, Julia; Popin, Rafael V.; Fewer, David P.; Sivonen, Kaarina (2020)
    Cyanobacteria produce an array of toxins that pose serious health risks to humans and animals. The closely related diazotrophic genera, Anabaena, Dolichospermum and Aphanizomenon, frequently form poisonous blooms in lakes and brackish waters around the world. These genera form a complex now termed the Anabaena, Dolichospermum and Aphanizomenon (ADA) clade and produce a greater array of toxins than any other cyanobacteria group. However, taxonomic confusion masks the distribution of toxin biosynthetic pathways in cyanobacteria. Here we obtained 11 new draft genomes to improve the understanding of toxin production in these genera. Comparison of secondary metabolite pathways in all available 31 genomes for these three genera suggests that the ability to produce microcystin, anatoxin-a, and saxitoxin is associated with specific subgroups. Each toxin gene cluster was concentrated or even limited to a certain subgroup within the ADA clade. Our results indicate that members of the ADA clade encode a variety of secondary metabolites following the phylogenetic clustering of constituent species. The newly sequenced members of the ADA clade show that phylogenetic separation of planktonic Dolichospermum and benthic Anabaena is not complete. This underscores the importance of taxonomic revision of Anabaena, Dolichospermum and Aphanizomenon genera to reflect current phylogenomic understanding.
  • Mantzouki, Evanthia; Lurling, Miquel; Fastner, Jutta; Domis, Lisette de Senerpont; Wilk-Wozniak, Elzbieta; Koreiviene, Judita; Seelen, Laura; Teurlincx, Sven; Verstijnen, Yvon; Krzton, Wojciech; Walusiak, Edward; Karosiene, Jurate; Kasperoviciene, Jurate; Savadova, Ksenija; Vitonyte, Irma; Cillero-Castro, Carmen; Budzynska, Agnieszka; Goldyn, Ryszard; Kozak, Anna; Rosinska, Joanna; Szelag-Wasielewska, Elzbieta; Domek, Piotr; Jakubowska-Krepska, Natalia; Kwasizur, Kinga; Messyasz, Beata; Pelechata, Aleksandra; Pelechaty, Mariusz; Kokocinski, Mikolaj; Garcia-Murcia, Ana; Real, Monserrat; Romans, Elvira; Noguero-Ribes, Jordi; Parreno Duque, David; Fernandez-Moran, Elisabeth; Karakaya, Nusret; Haggqvist, Kerstin; Demir, Nilsun; Beklioglu, Meryem; Filiz, Nur; Levi, Eti E.; Iskin, Ugur; Bezirci, Gizem; Tavsanoglu, Ulku Nihan; Ozhan, Koray; Gkelis, Spyros; Panou, Manthos; Fakioglu, Ozden; Yang, Yang; Salmi, Pauliina; Arvola, Lauri (2018)
    Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.