Insight into sodium selenite-induced metabolic reprogramming in response to main seleno-amino acid enrichment in Saccharomyces cerevisiae using metabolomics

Conversion of inorganic selenium (Se) to its organic form by Saccharomyces cerevisiae (S. cerevisiae) has attracted significant attention, for organic Se has higher nutritional value with less negative effects. However, the mechanism of transformation and accumulation of organic Se at the metabolic level remains unclear. We investigated the metabolic response to sodium selenite supplementation in culture medium at 0, 5, 15, and 45 mg/L in two S. cerevisiae strains using an ultra-high performance liquid chromatography-high resolution mass spectrometry-based untargeted method. In total, 455 metabolites were detected, and a separation trend was clearly observed between Se-treated groups and controls. In depth, metabolic pathways involving amino acid, nucleotide metabolism and tricarboxylic acid cycle were significantly affected. Furthermore, high inorganic-Se supplementation effectively decreased the seleno-amino acid proportion in total Se, inhibited cell growth, and decreased glutathione levels. These results provide novel insights into the Se-enrichment process of S. cerevisiae.