|
|
|
|
|
| Briand, Enora; Reubrecht, Sébastien; Mondeguer, Florence; Sibat, Manoella; Hess, Philipp; Amzil, Zouher; Bormans, Myriam. |
| Freshwater cyanobacteria are known for their ability to produce bioactive compounds, some of which have been described as allelochemicals. Using a combined approach of co‐cultures and analyses of metabolic profiles, we investigated chemically mediated interactions between two cyanobacterial strains, Microcystis aeruginosa PCC7806 and Planktothrix agardhii PCC7805. More precisely, we evaluated changes in growth, morphology and metabolite production and release by both interacting species. Co‐culture of Microcystis with Planktothrix resulted in a reduction of the growth of Planktothrix together with a decrease of its trichome size and alterations in the morphology of its cells. The production of intracellular compounds by Planktothrix showed a slight... |
| Tipo: Text |
|
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00470/58152/60632.pdf |
| |
|
|
| Briand, Enora; Reubrech, Sébastien; Mondeguer, Florence; Sibat, Manoella; Hess, Philipp; Amzil, Zouher; Bormans, Myriam. |
| Freshwater cyanobacteria are well known for their ability to produce a wide variety of bioactive compounds, some of which have been described as allelochemicals. There is growing evidence that these secondary metabolites play an important role in shaping community composition through biotic interactions; however, for the most part, their biological role and mode of regulation of the production are poorly understood. In temperate eutrophic freshwaters, Microcystis and Planktothrix often co-occur, with Planktothrix being an early colonizer and Microcystis appearing subsequently. We tested if the production of a range of peptides by co-existing species could be regulated through interspecific interactions. Using a combined approach of co-cultures and analyses... |
| Tipo: Text |
|
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00374/48515/48794.pdf |
| |
|
|
| Bojadzija Savic, Gorenka; Bormans, Myriam; Edwards, Christine; Lawton, Linda; Briand, Enora; Wiegand, Claudia. |
| Due to eutrophication, freshwater ecosystems frequently experience cyanobacterial blooms, many of which produce bioactive metabolites that can affect vertebrates and invertebrates life traits. Zooplankton are able to develop tolerance as a physiological response to cyanobacteria and their bioactive compounds, however, this comes with energetic cost that in turn influence Daphnia life traits and may impair populations. Vice versa, it has been suggested that Daphnia are able to reduce cyanobacterial dominance until a certain cyanobacterial density; it remains unclear whether Daphnia metabolites alone influence the physiological state and bioactive metabolites production of cyanobacteria. Hence, this study investigates mutual physiological reactions of toxic... |
| Tipo: Text |
Palavras-chave: Zooplankton; Cyanobacteria; Secondary metabolites; PCC7806; Toxic; Oxidative stress. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00624/73653/76105.pdf |
| |
|
|
| Bojadzija Savic, Gorenka; Edwards, Christine; Briand, Enora; Lawton, Linda; Wiegand, Claudia; Bormans, Myriam. |
| While the intracellular function of many toxic and bioactive cyanobacterial metabolites is not yet known, microcystins have been suggested to have a protective role in the cyanobacterial metabolism, giving advantage to toxic over nontoxic strains under stress conditions. The zooplankton grazer Daphnia reduce cyanobacterial dominance until a certain density, which may be supported by Daphnia exudates, affecting the cyanobacterial physiological state and metabolites’ production. Therefore, we hypothesized that D. magna spent medium will impact the production of cyanobacterial bioactive metabolites and affect cyanobacterial photosynthetic activity in the nontoxic, but not the toxic strain. Microcystin (MC-LR and des-MC-LR) producing M. aeruginosa PCC7806 and... |
| Tipo: Text |
Palavras-chave: Cyanobacteria; Secondary metabolites; PCC7806; Toxic; Mutant; Infochemicals. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00507/61893/65980.pdf |
| |
|
|
| Georges Des Aulnois, Maxime; Roux, Pauline; Caruana, Amandine; Réveillon, Damien; Briand, Enora; Hervé, Fabienne; Savar, Veronique; Bormans, Myriam; Amzil, Zouher; Atomi, Haruyuki. |
| Proliferation of microcystin (MC)-producing Microcystis aeruginosa in brackish waters has been described in several locations and represents a new concern for public and environmental health. While the impact of a sudden salinity increase on M. aeruginosa physiology has been studied, less is known about the mechanisms involved in salt tolerance after acclimation. This study aims to compare the physiological responses of two strains of M. aeruginosa (PCC 7820 and PCC 7806), which were isolated from contrasted environments, to increasing salinities. After acclimation, growth and MC production rates were determined and metabolomic analyses were conducted. For both strains, salinity decreased the biovolume, growth, and MC production rates and induced the... |
| Tipo: Text |
Palavras-chave: Acclimation; Metabolomic; Microcystis; Salinity; Sucrose; Trehalose; Ecophysiology. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00588/70031/68012.pdf |
| |
|
|
| Mondeguer, Florence; Sibat, Manoella; Reubrecht, Sébastien; Amzil, Zouher; Bormans, Myriam; Hess, Philipp; Briand, Enora. |
| Cyanobacterial proliferation is one of the most harmful hazards, in both freshwater and marine ecosystems. Cyanobacteria are well known for their ability to produce a wide variety of bioactive compounds, some of which have been described as allelochemicals. There is growing evidence that these secondary metabolites play an important role in shaping community composition through biotic interactions; however, for the most part, their biological role and mode of regulation of the production are poorly understood. In temperate eutrophic freshwaters, Microcystis and Planktothrix often co-occur, with Planktothrix being an early colonizer and Microcystis appearing subsequently. By integrating LC-MS/MS molecular networking and an innovative experimental design, we... |
| Tipo: Text |
Palavras-chave: Cyanobacteria; Cyanotoxins; Plankton interactions; Co_culture; LC_HRMS; Molecular Network; Metabolomics. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00405/51666/52215.pdf |
| |
|
|
| Georges Des Aulnois, Maxime; Réveillon, Damien; Robert, Elise; Caruana, Amandine; Briand, Enora; Guljamow, Arthur; Dittmann, Elke; Amzil, Zouher; Bormans, Myriam. |
| The transfer of Microcystis aeruginosa from freshwater to estuaries has been described worldwide and salinity is reported as the main factor controlling the expansion of M. aeruginosa to coastal environments. Analyzing the expression levels of targeted genes and employing both targeted and non-targeted metabolomic approaches, this study investigated the e ect of a sudden salt increase on the physiological and metabolic responses of two toxic M. aeruginosa strains separately isolated from fresh and brackish waters, respectively, PCC 7820 and 7806. Supported by di erences in gene expressions and metabolic profiles, salt tolerance was found to be strain specific. An increase in salinity decreased the growth of M. aeruginosa with a lesser impact on the... |
| Tipo: Text |
Palavras-chave: Microcystis aeruginosa; Microcystin; Salt stress; Metabolomic; Transcript. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00615/72689/71692.pdf |
| |
|
|
|
