Glutathione serves an extracellular defence function to decrease arsenite accumulation and toxicity in yeast.
Journal article, 2012
Arsenic is an environmental toxin and a worldwide health hazard. Since this metalloid is ubiquitous in nature, virtually all living organisms require systems for detoxification and tolerance acquisition. Here, we show that during chronic exposure to arsenite [As(III)], Saccharomyces cerevisiae (budding yeast) exports and accumulates the low-molecular-weight thiol molecule glutathione (GSH) outside of cells. Extracellular accumulation of the arsenite triglutathione complex As(GS)₃ was also detected and direct transport assays demonstrate that As(GS)₃ does not readily enter cells. Yeast cells with increased extracellular GSH levels accumulate less arsenic and display improved growth when challenged with As(III). Conversely, cells defective in export and extracellular accumulation of GSH are As(III) sensitive. Taken together, our data are consistent with a novel detoxification mechanism in which GSH is exported to protect yeast cells from arsenite toxicity by preventing its uptake.
drug effects
metabolism
growth & development
antagonists & inhibitors
Saccharomyces cerevisiae
Drug
antagonists & inhibitors
Arsenites
Antifungal Agents
Metabolic Detoxication
metabolism
metabolism
metabolism
Glutathione
Author
Michael Thorsen
University of Gothenburg
Therese Jacobson
University of Gothenburg
Riet Vooijs
Clara Navarrete Roman
University of Gothenburg
Tijs Bliek
Henk Schat
Markus J. Tamás
University of Gothenburg
Molecular Microbiology
0950-382X (ISSN) 1365-2958 (eISSN)
Vol. 84 6 1177-88Subject Categories
Biochemistry and Molecular Biology
Microbiology
DOI
10.1111/j.1365-2958.2012.08085.x
PubMed
22554109