Article
Microbiology
Paul M. D'Agostino, Anna C. Y. Yeung, Anne Poljak, Trevor David Waite, Brett A. Neilan
Summary: This study compares the proteomic responses of different toxic and non-toxic strains of Raphidiopsis raciborskii under reduced iron concentrations, revealing that the toxic strain is more competitive during the exponential growth phase, while the non-toxic strain shows reduced protein expression in multiple primary metabolism pathways.
ENVIRONMENTAL MICROBIOLOGY
(2021)
Article
Biotechnology & Applied Microbiology
Lais Albuquerque Giraldi, Sarah Regina Vargas, Paulo Vagner Santos, Alessandra Emanuele Tonietto, Flavia Vischi Winck, Maria do Carmo Calijuri
Summary: The study reveals that high Cu2+ concentrations can stimulate toxin synthesis in cyanobacteria and microalgae, particularly increasing saxitoxins (STXs) production in early growth stages. Although cell concentration and biovolume decrease in high Cu2+ conditions, cell volume increases, indicating the potential toxicity of Raphidiopsis raciborskii.
JOURNAL OF APPLIED PHYCOLOGY
(2021)
Article
Engineering, Environmental
Zhe Lu, Jinmei Ye, Zhijiang Chen, Lijuan Xiao, Lamei Lei, Bo-ping Han, Hans W. Paerl
Summary: Nutrient storage is a critical strategy for algae to adapt to changing nutrient supply. This study found that cyanophycin storage supports persistent dominance and blooms of cyanobacteria in tropical waters, particularly during nitrogen-deficient seasons.
Article
Environmental Sciences
Zakaria A. Mohamed, Saad Alamri, Mohamed Hashem, Yasser Mostafa
Summary: This study found that a yeast strain isolated from a lake can eliminate cyanobacteria and their toxin. The yeast removes the toxin by adsorption rather than degradation. The study also showed that heat-inactivated yeast has a higher removal capacity.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Microbiology
Laisa Correa Braga Marques, Joni Esrom Lima, Juliana da Silva Martins Pimentel, Alessandra Giani
Summary: This study investigated the response of cyanobacteria Raphidiopsis raciborskii to nitrogen limitation and its genetic background, shedding new light on heterocyte production and phylogeography. The findings suggest that heterocyte development in R. raciborskii is not regulated by nitrogen availability. Genetic analysis revealed differences between strains. The study also confirmed Raphidiopsis and Cylindrospermopsis as the same genus and proposed new hypotheses on the biogeography of the species.
FEMS MICROBIOLOGY ECOLOGY
(2022)
Article
Environmental Sciences
Zakaria Mohamed, Saad Alamri, Mohamed Hashem
Summary: This study found that a Bacillus flexus strain has the capability to bioremediate Cylindrospermopsis raciborskii and cylindrospermopsin (CYN) toxin, as well as inhibit the growth of cyanobacteria. The living bacterial cells and bacterial filtrate have significant effects on the growth of C. raciborskii and the degradation of CYN toxin.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Multidisciplinary Sciences
Vanessa Krauspe, Matthias Fahrner, Philipp Spat, Claudia Steglich, Nicole Frankenberg-Dinkel, Boris Macek, Oliver Schilling, Wolfgang R. Hess
Summary: The protein NblD plays a crucial role in the degradation of phycobilisomes in cyanobacteria under nitrogen-limited conditions. Studies have shown that NblD is essential for maintaining normal growth of cyanobacterial cells during nitrogen limitation.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Marine & Freshwater Biology
Tanise Klein Ramos, Luiza Dy Fonseca Costa, Joao Sarkis Yunes, Charrid Resgalla, Jose Bonomi Barufi, Eduardo de Oliveira Bastos, Paulo Antunes Horta, Leonardo Rubi Rorig
Summary: The study found that the STX-producing R. raciborskii has been present in the waters of Peri Lake in southern Brazil for years, posing potential risks to the local population's water supply. Experimental results showed that STX concentrations are particularly high in warmer months, even reaching the coastal zone. The experiments also indicated that R. raciborskii strains have varying tolerances to different salinities, which in turn affect STX production, while mussels feeding on R. raciborskii can absorb and accumulate STX.
Article
Marine & Freshwater Biology
Lucia Gonzalez-Madina, Paula Levrini, Paula de Tezanos Pinto, Maite Burwood, Carolina Crisci, Andrea Cardozo, Juan Jose Lagomarsino, Juan Pablo Pacheco, Claudia Fosalba, Gustavo Mendez, Lydia Garrido, Nestor Mazzeo
Summary: Laguna del Sauce in Uruguay is a eutrophic shallow lake and the second drinking water source, where recurrent blooms of toxic cyanobacteria Raphidiopsis raciborskii have been recorded from 2003 to 2020, impacting the drinking water supply. A monitoring program was established after the 2015 bloom, which improved the understanding of environmental drivers and led to adjustments in ecosystem management and water treatment strategies.
Article
Environmental Sciences
Leila dos Santos Machado, Fabiane Dorr, Felipe Augusto Dorr, Daniele Frascareli, Darllene S. Melo, Erik S. J. Gontijo, Kurt Friese, Ernani Pinto, Andre Henrique Rosa, Marcelo M. Pompeo, Viviane Moschini-Carlos
Summary: Toxic cyanobacteria blooms are a common issue in subtropical reservoirs and freshwater systems. This study investigated the presence of potentially toxic cyanobacteria and the environmental conditions associated with cyanotoxins in a Brazilian subtropical reservoir. Raphidiopsis raciborskii was found to be permanently present in the reservoir, with significant impact on the levels of Saxitoxin (STX) and Microcystin (MC). The study also revealed the sensitivity of R. raciborskii to thermal stratification and the potential production of STX under growth-restricting conditions.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Marine & Freshwater Biology
Fengjiao Tan, Peng Xiao, Jun R. Yang, Huihuang Chen, Lei Jin, Yigang Yang, Tsair-Fuh Lin, Anusuya Willis, Jun Yang
Summary: A duplex digital PCR monitoring approach was developed and validated for the detection of the abundance and toxin-producing potential of the toxic cyanobacterium, Raphidiopsis raciborskii. This method showed higher precision compared to traditional methods at low cell concentration and had the highest detection rate in over two hundred environmental samples.
Article
Marine & Freshwater Biology
Vanessa Virginia Barbosa, Ranielle Daiana dos Santos Silva, Juliana dos Santos Severiano, Mathias Ahii Chia, Jose Etham de Lucena Barbosa
Summary: Investigations on the influence of green microalgae associated with cyanobacteria exposure to macrophytes and the production of cyanotoxins have not been previously explored. The effects of the presence of live plants and extracts of the Egeria densa, on the growth and saxitoxin production of Raphidiopsis raciborskii were investigated in the presence and absence of Chlorella vulgaris. The physical presence of the macrophyte reduced the biovolume of the cyanobacterium and its production of saxitoxins, while cultures exposed to aqueous extract had elevated saxitoxin levels. The green microalgae also increased the amount of cyanotoxins, especially when the macrophyte biomass was low. These findings suggest that E. densa can inhibit the growth of R. raciborskii and the production of cyanotoxins and that the presence of C. vulgaris can alter these processes.
Article
Environmental Sciences
Michal Adamski, Eliza Zimolag, Ariel Kaminski, Justyna Drukala, Jan Bialczyk
Summary: Cyanotoxins produced by cyanobacteria pose significant threats to human keratinocytes, inhibiting proliferation and migration, and causing cytotoxic effects. Among them, CYN and its decomposition products exhibit strong inhibitory effects on keratinocytes, while ANTX-a shows lower toxicity, requiring higher concentrations and longer exposure. Further research on cyanotoxins should focus on their decomposition products and ecotoxicology in natural aquatic environments.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Marine & Freshwater Biology
M. A. Burford, H. Franklin, S. J. Faggotter, A. Chuang, J. B. Hayton, A. R. Carroll
Summary: The concentration of coloured terrestrial dissolved organic matter (tDOM) from vegetation is increasing in lakes, leading to brownification. The phytotoxic effects of tDOM on cyanobacterial blooms are not well understood. This study found that tDOM leachate from Eucalyptus leaves inhibited the photosynthesis and growth of cyanobacteria, even at lower densities, and the effect was more significant at higher tDOM input loads.
Article
Microbiology
Lamei Lei, Minting Lei, Nan Cheng, Zhijiang Chen, Lijuan Xiao, Bo-Ping Han, Qiuqi Lin
Summary: Raphidiopsis raciborskii has both toxic and non-toxic strains co-existing in natural water bodies, with the toxic strains having a competitive advantage in eutrophic environments, resulting in the production of more toxic blooms.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Food Science & Technology
Luis Puente, Antonio Vega-Galvez, Ivette Fuentes, Karina Stucken, Angela Rodriguez, Alexis Pasten
Summary: The study found that drying methods at high temperatures have positive effects on the physico-chemical properties, color, antioxidant capacity, tocopherol, and fatty acids content of physalis pulp. Different drying methods also significantly impact the chromatic parameters and hue angle of the pulp.
JOURNAL OF FOOD SCIENCE AND TECHNOLOGY-MYSORE
(2021)
Article
Microbiology
Cora Hoerstmann, Pier Luigi Buttigieg, Uwe John, Eric J. Raes, Dieter Wolf-Gladrow, Astrid Bracher, Anya M. Waite
Summary: This study investigated microbial diversity and primary productivity in the Atlantic Ocean between 50 degrees south and north, revealing distinct diversity patterns among different provinces. Samplewise productivity-specific length scales were calculated to provide key context for further analysis, linking diversity patterns to oceanographic transport through primary production.
ENVIRONMENTAL MICROBIOLOGY
(2022)
Article
Biodiversity Conservation
Alexandre Fellous, K. Mathias Wegner, Uwe John, Felix C. Mark, Lisa N. S. Shama
Summary: Our study revealed that parental acclimation to ocean warming results in dynamic and temperature-sensitive reprogramming of epigenetics and gene expression during offspring development in marine stickleback. Different warming scenarios led to significant changes in global methylation/hydroxymethylation and gene expression related to epigenetic modifications, suggesting potential 'windows of opportunity' for adaptive epigenetic responses under future climate change.
GLOBAL CHANGE BIOLOGY
(2022)
Correction
Ecology
Andreas Altenburger, Huimin Cai, Qiye Li, Kirstine Drumm, Miran Kim, Yuanzhen Zhu, Lydia Garcia-Cuetos, Xiaoyu Zhan, Per Juel Hansen, Uwe John, Shuaicheng Li, Nina Lundholm
Article
Biochemistry & Molecular Biology
Meike A. C. Latz, Vesna Grujcic, Sonia Brugel, Jenny Lycken, Uwe John, Bengt Karlson, Agneta Andersson, Anders F. Andersson
Summary: In this study, new primers targeting 18S and 28S rRNA were designed and evaluated in vitro and in vivo. The results showed that a new V6-V8 primer pair and the V4_Balzano primer pair performed well in short-read sequencing, while fewer differences were observed between long-read primer pairs. Long-read amplicons and ITS1 alone provided higher taxonomic resolution than V4. These findings provide a reference and guide for the selection of robust primers for research on and environmental monitoring of microbial eukaryotes.
MOLECULAR ECOLOGY RESOURCES
(2022)
Article
Environmental Sciences
Jon Lapeyra Martin, Uwe John, Colin Royer, Nathalie Gypens
Summary: Protists engaging in photo- and phago- mixotrophy are common in global plankton community and play important roles in carbon and nutrient cycling. This study investigated the diversity and temporal succession of mixoplankton in the Belgian Coastal Zone, revealing distinct seasonal patterns and major contributors to the mixoplankton community.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Marine & Freshwater Biology
Uwe John, Luka Supraha, Sandra Gran-Stadniczenko, Carina Bunse, Allan Cembella, Wenche Eikrem, Jan Janouskovec, Kerstin Klemm, Nancy Kuehne, Lars Naustvoll, Daniela Voss, Sylke Wohlrab, Bente Edvardsen
Summary: A bloom of the fish-killing haptophyte Chrysochromulina leadbeateri occurred in northern Norway in 2019, causing massive mortalities of farmed salmon. Studies have revealed that C. leadbeateri was the primary cause of fish mortalities. The distribution and cell abundance of C. leadbeateri were influenced by temperature, salinity, and nutrient concentrations. Multiple Chrysochromulina variants were identified.
Article
Marine & Freshwater Biology
Elena Alabarces Alvarez, Kerstin Klemm, Mona Hoppenrath, Allan Cembella, Uwe John, Bengt Karlson
Summary: This study investigated the biodiversity and distribution of potentially toxic epibenthic dinoflagellates along the west coast of Sweden, confirming the presence of two toxigenic species. The study found no significant temporal variation in cell densities of these species over two summers. The results suggest a potential risk of diarrhetic shellfish poisoning events caused by one of the species, highlighting the importance of monitoring and management in shellfish aquaculture.
Article
Marine & Freshwater Biology
Kerstin Klemm, Allan Cembella, Dave Clarke, Caroline Cusack, Lars Arneborg, Bengt Karlson, Ye Liu, Lars Naustvoll, Raffaele Siano, Sandra Gran-Stadniczenko, Uwe John
Summary: This article provides a comprehensive study on the marine dinoflagellate genus Alexandrium Halim, including species diversity, life history strategies, toxigenicity, biogeographical distribution, and the global consequences of harmful algal blooms (HABs). It also discusses the importance of human adaptive actions, climate change impacts, and effective adaptation strategies for Alexandrium blooms.
Review
Engineering, Marine
Cora Hoerstmann, Sylke Wohlrab, Uwe John
Summary: High-throughput sequencing technologies have advanced our understanding of microbial diversity in the oceans, but research on microbial eukaryotes (protists) lags behind. This review discusses the challenges and opportunities of high-throughput sequencing methods for studying the evolutionary, ecological, and functional aspects of oceanic protists. These approaches allow for a deeper understanding of the functional role of protists and the changes in marine ecosystems.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Genetics & Heredity
Antonia Ahme, Anabel Von Jackowski, Rebecca A. McPherson, Klara K. E. Wolf, Mario Hoppmann, Stefan Neuhaus, Uwe John
Summary: As new species intrude into Arctic microbial communities via Atlantification and ocean warming, the composition and function of the ecosystem may change. Our study found that increasing the temperature to 9 degrees C significantly reduces diversity and alters the composition, while a temperature of 6 degrees C has only minor effects. The abundance of different organisms varies with temperature, indicating a thermal limit between 6 degrees C and 9 degrees C for many Arctic species.
Article
Plant Sciences
Hisatake Ishida, Uwe John, Shauna A. Murray, Debashish Bhattacharya, Cheong Xin Chan
Summary: Dinoflagellates are diverse eukaryotic microbes found in aquatic environments, with various trophic strategies and the ability to produce bioactive secondary metabolites. They hold great potential for understanding evolutionary and genomic complexities discussed in this article, and the development of fit-to-purpose models that consider their diverse biology and ecology is necessary. The accessibility, tractability, resources, research support, and promise of dinoflagellates as model organisms are also highlighted.
JOURNAL OF PHYCOLOGY
(2023)
Article
Environmental Sciences
Luka Supraha, Kerstin Klemm, Sandra Gran-Stadniczenko, Cora Horstmann, Daniel Vaulot, Bente Edvardsen, Uwe John
Summary: Understanding the community structure of Arctic phytoplankton is crucial for predicting the response of Arctic ecosystems to ocean warming. This study investigated the diversity and biogeography of diatoms in the Svalbard area and found that they exhibit different biogeographic distribution types and are structured by local environmental gradients. The finer biogeographic patterns observed within certain genotypes suggest that they can serve as indicators of the influence of Atlantic waters on the phytoplankton community in the region.
ELEMENTA-SCIENCE OF THE ANTHROPOCENE
(2022)
Article
Environmental Sciences
Peter Stief, Clemens Schauberger, Marie B. Lund, Andreas Greve, Raeid M. M. Abed, Mohammad A. A. Al-Najjar, Karl Attard, Stefano Bonaglia, Jorg S. Deutzmann, Belen Franco-Cisterna, Emilio Garcia-Robledo, Moritz Holtappels, Uwe John, Adele Maciute, Michael J. Magee, Rie Pors, Tina Santl-Temkiv, Anja Scherwass, Duygu S. Sevilgen, Dirk de Beer, Ronnie N. Glud, Andreas Schramm, Anja Kamp
Summary: Diatoms play a crucial role in nitrogen cycling in aquatic ecosystems by storing and utilizing nitrate intracellularly, with a potentially significant impact on benthic nitrogen cycling.
COMMUNICATIONS EARTH & ENVIRONMENT
(2022)