Premium
Glutathione serves an extracellular defence function to decrease arsenite accumulation and toxicity in yeast
Author(s) -
Thorsen Michael,
Jacobson Therese,
Vooijs Riet,
Navarrete Clara,
Bliek Tijs,
Schat Henk,
Tamás Markus J.
Publication year - 2012
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/j.1365-2958.2012.08085.x
Subject(s) - arsenite , glutathione , extracellular , biology , yeast , saccharomyces cerevisiae , arsenic , arsenic toxicity , detoxification (alternative medicine) , biochemistry , toxicity , microbiology and biotechnology , chemistry , enzyme , medicine , alternative medicine , organic chemistry , pathology
Summary 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.