| Title: | Daphnia magna Exudates Impact Physiological and Metabolic Changes in Microcystis aeruginosa |
| Author(s): | Bojadzija Savic G; Edwards C; Briand E; Lawton L; Wiegand C; Bormans M; |
| Address: | "Univ Rennes, CNRS, ECOBIO-UMR 6553, F-35000 Rennes, France. gorenka.bojadzija@univ-rennes1.fr. School of Pharmacy and Life Sciences, Robert Gordon University, Aberdeen AB10 7GJ, UK. IFREMER, Phycotoxins Laboratory, F-44311 Nantes, France. Univ Rennes, CNRS, ECOBIO-UMR 6553, F-35000 Rennes, France" |
| ISSN/ISBN: | 2072-6651 (Electronic) 2072-6651 (Linking) |
| Abstract: | "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 its non-microcystin producing mutant were exposed to spent media of different D. magna densities and culture durations. D. magna spent medium of the highest density (200/L) cultivated for the shortest time (24 h) provoked the strongest effect. D.magna spent medium negatively impacted the photosynthetic activity of M. aeruginosa PCC7806, as well as the dynamics of intracellular and extracellular cyanobacterial metabolites, while its mutant was unaffected. In the presence of Daphnia medium, microcystin does not appear to have a protective role for the strain. On the contrary, extracellular cyanopeptolin A increased in M. aeruginosa PCC7806 although the potential anti-grazing role of this compound would require further studies" |
| Keywords: | Animals Daphnia/*chemistry Microcystins/metabolism Microcystis/*drug effects/physiology Photosynthesis Pcc7806 cyanobacteria infochemicals mutant secondary metabolites toxic; |
| Notes: | "MedlineBojadzija Savic, Gorenka Edwards, Christine Briand, Enora Lawton, Linda Wiegand, Claudia Bormans, Myriam eng Research Support, Non-U.S. Gov't Switzerland 2019/07/25 Toxins (Basel). 2019 Jul 19; 11(7):421. doi: 10.3390/toxins11070421" |
