Article
Engineering, Environmental
Ziru Lian, Fang Li, Xiuping He, Junhui Chen, Ren-Cheng Yu
Summary: Increasing levels of CO2 can promote the growth and toxicity of toxic dinoflagellate Alexandrium minutum, leading to an increase in paralytic shellfish toxins (PSTs) production. This study highlights the potential risk of ocean acidification on the formation and evolution of harmful algal blooms.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Food Science & Technology
Epaminondas D. Christou, Ioanna Varkitzi, Isabel Maneiro, Soultana Zervoudaki, Kalliopi Pagou
Summary: Researchers conducted a series of experiments to study the effects of toxic dinoflagellate on the feeding, reproduction, and toxin excretion of copepods. They found that the toxicity of the dinoflagellate affected the reproduction, toxin excretion, and feeding behavior of the copepods, indicating the significant impact of toxins on copepods.
Article
Marine & Freshwater Biology
Massimo C. Pernice, Daniel Closa, Esther Garces
Summary: Extracellular Vesicles (EVs) are believed to be an important method of transport and communication in the marine microbial community. However, isolating and characterizing EVs from axenic cultures of microbial eukaryotes remains a technological challenge. This study successfully isolated EVs from a near-axenic culture of the toxic dinoflagellate Alexandrium minutum using Cryo TEM. The EVs were classified into five major groups based on their morphotype and were found to have an average diameter of 0.36 μm. This descriptive work aims to be the first step in studying the potential role of EVs in the toxicity of dinoflagellates.
Article
Ecology
Jeonghoon Han, Joon Sang Park, Jihoon Lee, Yeun Park, Hyeon Ho Shin, Young-Ung Choi, Kyun-Woo Lee
Summary: The study assessed the acute toxicity and swimming behavior of the marine copepod Tigriopus japonicus in response to the toxic dinoflagellate Alexandrium minutum, finding no significant changes in survival and swimming behavior, but significant modulation of detoxification-related genes (CYPs and GSTs) expression levels. This indicates that CYP and GST genes may play crucial roles in detoxification mechanisms in T. japonicus, leading to no significant changes in survival and swimming behavior in response to A. minutum exposure.
JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY
(2021)
Article
Biotechnology & Applied Microbiology
Quynh Thi Nhu Bui, Han-Sol Kim, Jang-Seu Ki
Summary: This study evaluated the effect of low salinity on the toxic dinoflagellate Alexandrium pacificum. The results showed that low salinity led to a decrease in cell density, an increase in cell size, and a decrease in photosynthesis efficiency. Additionally, low salinity induced cellular oxidative stress and affected the antioxidant systems in the toxic dinoflagellates.
JOURNAL OF APPLIED PHYCOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Quynh Thi Nhu Bui, Hansol Kim, Hui Wang, Jang-Seu Ki
Summary: By studying the sxtA gene sequences of two toxic dinoflagellates, it was found that there are differences in their gene coding structure and evolutionary history. The evolution of sxtA in Alexandrium may involve acquiring specific domains, which significantly affect toxin biosynthesis.
MOLECULAR PHYLOGENETICS AND EVOLUTION
(2022)
Article
Environmental Sciences
Quynh Thi Nhu Bui, Jang-Seu Ki
Summary: This study characterized the structural features and phylogenetic affiliations of two novel CuZnSOD and MnSOD genes from the toxic marine dinoflagellate Alexandrium pacificum. The study also examined the gene expression and reactive oxygen species (ROS) levels after exposure to heavy metals. The results showed that ApCuZnSOD clustered with other dinoflagellates, while ApMnSOD formed a clade with green algae and plants. Increased SOD expression levels and ROS production were observed after exposure to lead and copper.
Article
Microbiology
Solene Geffroy, Marc-Marie Lechat, Mickael Le Gac, Georges-Augustin Rovillon, Dominique Marie, Estelle Bigeard, Florent Malo, Zouher Amzil, Laure Guillou, Amandine M. N. Caruana
Summary: This study explored the relationship between toxin production and gene structure in dinoflagellates, particularly focusing on the sxtA4 gene copy number and genome size. It was found that there is a significant correlation between the sxtA4 gene copy number and toxin content, as well as a moderate positive correlation between the sxtA4 gene copy number and genome size. Additionally, toxic and non-toxic strains exhibited differential expression and specific allelic forms of the sxtA4 gene, supporting the hypothesis of genetic determinism in toxin synthesis by A. minutum.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Oceanography
Changyou Wang, Ping Zheng, Haifeng Gu, Zhaohe Luo, Zhuhua Luo, Longjiang Mao, Yuanzhi Zhang
Summary: This study predicts the potential distribution of Alexandrium minutum in the China Sea using maximum entropy modeling. The results show highly suitable areas in the southwest of the Yellow Sea, Laizhou Bay, and north of Haizhou Bay, while the coast of the South China Sea is predicted as low-suitability and the coast of the East China Sea as unsuitable. The presence of A. minutum is influenced by mean temperature of the coldest month, nitrate concentration, and annual mean temperature. Low phosphate concentration and N_P_ratio favor the occurrence of A. minutum.
JOURNAL OF OCEAN UNIVERSITY OF CHINA
(2023)
Article
Biochemistry & Molecular Biology
Yujue Wang, Moli Li, Jiarun Lou, Xiaogang Xun, Lirong Chang, Yangrui Wang, Quanqi Zhang, Longfei Lu, Huizhen Wang, Jingjie Hu, Zhenmin Bao, Xiaoli Hu
Summary: This study provides insights into the molecular mechanism of bivalve resistance to paralytic shellfish toxins (PST) by examining the gene set involved in PST accumulation in scallop gills. Transcriptomic analysis revealed different response mechanisms of scallop to PST-producing dinoflagellate at different stages of exposure. The study also found that PST exposure affects nervous system development, xenobiotic metabolism, substance transport, and immune functions, ultimately leading to apoptosis.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Environmental Sciences
Justine Castrec, Caroline Fabioux, Nelly Le Goic, Myrina Boulais, Philippe Soudant, Helene Hegaret
Summary: The study revealed that the bioactive extracellular compounds produced by Alexandrium minutum have significant cellular toxicity on oyster gametes, leading to reduced viability and fertilization capacity when exposed to high densities of A. minutum. Specifically, the strain producing BEC showed stronger inhibitory effects on sperm motility and ROS production in oocytes, resulting in decreased fertilization at concentrations as low as 2.5 x 103 cells mL-1.
MARINE ENVIRONMENTAL RESEARCH
(2021)
Article
Environmental Sciences
Eyal Rahav, Barak Herut
Summary: Experiments have shown that increasing temperature and triazine-type herbicides pollution can make toxic dinoflagellate Alexandrium minutum more susceptible to pollution, leading to a decrease in abundance and photosynthetic activity, as well as an increase in saxitoxin gene expression. This suggests that saxitoxin poisoning may occur in warming polluted coastal areas even without a massive bloom.
MARINE POLLUTION BULLETIN
(2023)
Article
Biotechnology & Applied Microbiology
Hui Wang, Hansol Kim, Jang-Seu Ki
Summary: The study characterized the transcriptome of marine dinoflagellate Alexandrium pacificum under various stresses, revealing numerous stress-responsive genes with potential diverse origins. Specifically, genes related to antioxidant enzymes, heat shock proteins, carotenoid biosynthesis, and other stress-responsive genes were identified. The findings suggest that A. pacificum possesses a range of stress-resistant genes that may aid in adaptation to new environments.
JOURNAL OF APPLIED PHYCOLOGY
(2021)
Article
Environmental Sciences
Leilen L. Gracia Villalobos, Leandro N. Getino Mamet, Nuria Vazquez, Gaspar Soria, Rodrigo J. Goncalves
Summary: The effects of the toxic dinoflagellate Alexandrium catenella on the Tehuelche scallop Aequipecten tehuelchus were investigated. The study found that exposure to A. catenella reduced larvae survival and impacted growth rates. Histopathological effects were also observed in spat exposed to the dinoflagellate.
MARINE ENVIRONMENTAL RESEARCH
(2023)
Article
Chemistry, Medicinal
Cheng-Zhe Ren, Hui-Min Gao, Jun Dai, Wen-Zhuo Zhu, Fei-Fei Xu, Yun Ye, Xiao-Ling Zhang, Qiao Yang
Summary: This study isolated a new bacterial strain LZ-28 from a harmful algal bloom-forming dinoflagellate and revealed its symbiotic relationship with the algal strain. The strain LZ-28 showed high production ability for bioflocculant exopolysaccharides (EPS), with glucose and fucose contributing to its bioflocculant capacity. Comparative genomic analysis also revealed the similarities among selected M. alba strains. This research highlights the potential applications of the active EPS produced by the Mameliella alba strain LZ-28.
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
Genetics & Heredity
Bardya Djahanschiri, Gisela Di Venanzio, Jesus Distel, Jennifer F. Breisch, Marius Alfred Dieckmann, Alexander Goesmann, Beate Averhoff, Stephan Goettig, Gottfried Wilharm, Mario Feldman, Ingo Ebersberger
Summary: This study investigates the genetic basis of human-pathogen interaction in Acinetobacter calcoaceticus-baumannii (ACB) complex, a group of multi-drug resistant bacteria. By analyzing over 3,000 Acinetobacter genomes, the researchers identify evolutionarily stable gene clusters (ESGCs) that are associated with the pathogenic phenotype. These clusters reveal the metabolic pathways, transcriptional regulators, and carbon source utilization that allow the pathogens to adapt to their human host. The study also demonstrates that the ACB clade has the unique ability to utilize kynurenine, a substance produced by humans as part of the immune response. This research provides valuable insights for the development of novel therapeutic strategies.
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
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.
Article
Biotechnology & Applied Microbiology
Katharina Doll-Nikutta, Andreas Winkel, Ines Yang, Anna Josefine Grote, Nils Meier, Mosaieb Habib, Henning Menzel, Peter Behrens, Meike Stiesch
Summary: This study provides insights into the initial adhesion of oral bacteria and supports the development of infection-resistant implant materials in the future.
BIOENGINEERING-BASEL
(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
Microbiology
Celine M. Riyanti, Celine M. Zumkeller, Marius Spohn, Sanja Mihajlovic, Oliver Schwengers, Alexander Goesmann, Riviani Riviani, Maria D. N. F. Meinita, Till F. Schaeberle, Harwoko Harwoko
Summary: Sinomicrobium sp. strain PAP.21 (EXT111902) was isolated from the coast of Cenderawasih Bay National Park in West Papua, Indonesia. Its genome was assembled into 151 contigs with a total size of 5.439 Mbp, enabling the prediction of its specialized metabolite production capacity.
MICROBIOLOGY RESOURCE ANNOUNCEMENTS
(2023)
Article
Microbiology
Celine M. Riyanti, Celine Zumkeller, Marius Spohn, Sanja Mihajlovic, Oliver Schwengers, Alexander A. Goesmann, Nur F. Choironi, Till Schaberle, Harwoko Harwoko
Summary: In this study, we report the draft genome sequences of two strains, Algoriphagus sp. strain PAP.12 (EXT111900) and Roseivirga sp. strain PAP.19 (EXT111901), isolated from marine samples. We also evaluated their specialized metabolite production capacity. Genome-based analysis suggests that Algoriphagus sp. strain PAP.12 represents a candidate new species.
MICROBIOLOGY RESOURCE ANNOUNCEMENTS
(2023)
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)