Gut microbiome of Oryzias latipes expose to 4 Microcystis strains of cyanobacteria

The present study seeks to gain insight into the diversity of the toxic mechanisms of freshwater cyanobacteria by investigating the effect of extracts and cultures of selected French Microcystis strains belonging to distinct genotypes on the embryos and the adults of the Medaka fish Oryzias latipes. Four selected strains were previously initially characterized to determine the genuine potentially bioactive metabolites they produce according to combined genome mining and metabolomic investigations. Based on the implementation of a comprehensive battery of bioassays performed on both toxic, developmental, molecular and microbiota levels, this study provides new insights into the complexity of toxic potencies of four different Microcystis genotypes been known to produce yet recognized toxins, such as microcystins, or not. Overall, this work reveals the diversity of the cause of concern molecules produced by these different Microcystis strains and the corresponding large spectra of alterations they may induce on fish fitness.