Metabolic Response of the Yeast Candida utilis During Enrichment in Selenium

Marek Kieliszek , Katarzyna Bierla (1) , Javier Jiménez-Lamana (1) , Anna Maria Kot , Jaime Alcántara-Durán , Kamil Piwowarek , Stanisław Błażejak , Joanna Szpunar (1)

1 IPREM - Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux

Selenium (Se) was found to inhibit the growth of the yeast Candida utilis ATCC 9950. Cells cultured in 30 mg selenite/L supplemented medium could bind 1368 µg Se/g of dry weight in their structures. Increased accumulation of trehalose and glycogen was observed, which indicated cell response to stress conditions. The activity of antioxidative enzymes (glutathione peroxidase, glutathione reductase, thioredoxin reductase, and glutathione S-transferase) was significantly higher than that of the control without Se addition. Most Se was bound to water-insoluble protein fraction; in addition, the yeast produced 20-30 nm Se nanoparticles (SeNPs). Part of Se was metabolized to selenomethionine (10%) and selenocysteine (20%). The HPLC-ESI-Orbitrap MS analysis showed the presence of five Se compounds combined with glutathione in the yeast. The obtained results form the basis for further research on the mechanisms of Se metabolism in yeast cells.

Mots clés: selenium; Candida; yeast; antioxidant enzymes; selenium speciation

Domaines: Chimie

Marek Kieliszek, Katarzyna Bierla, Javier Jiménez-Lamana, Anna Maria Kot, Jaime Alcántara-Durán, et al.. Metabolic Response of the Yeast Candida utilis During Enrichment in Selenium. International Journal of Molecular Sciences, 2020, 21 (15), ⟨10.3390/ijms21155287⟩. ⟨hal-03133494⟩