title: Yeast as a biosensor for antioxidants: simple growth tests employing a Saccharomyces cerevisiae mutant defective in superoxide dismutase.
abstract: Mutants of Saccharomyces cerevisiae devoid of Cu,Zn-superoxide dismutase are hypersensitive to a range of oxidants, hyperbaric oxygen and hyperosmotic media, show lysine and methionine auxotrophy when grown under the atmosphere of air and have a shortened replicative life span when compared to the wild-type strain. Ascorbate and other antioxidants can ameliorate these defects, which may be a basis of simple tests sensing the presence of antioxidants. In particular, tests of growth on solid medium (colony formation) in the absence of methionine and/or lysine, or in the presence of 0.8 M NaCl can be useful for detection and semiquantitative estimation of compounds of antioxidant properties. Hypoxic atmosphere was found to increase the sensitivity of detection of antioxidants. The test of abolishment of lysine auxotrophy showed a concentration dependence of the antioxidant effects of cysteine and N-acetylcysteine which, however, lost their protective action at high concentration, in contrast to glutathione which was effective also at higher concentrations.
authors.affiliation: Department of Biochemistry and Cell Biology, University of Rzeszów, Rzeszów, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Zyracka
authors.forename: Renata
authors.initials: R
authors.lastname: Zadrag
authors.forename: Sabina
authors.initials: S
authors.lastname: Kozioł
authors.forename: Anna
authors.initials: A
authors.lastname: Krzepiłko
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Bartosz
authors.forename: Tomasz
authors.initials: T
authors.lastname: Biliński
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000388:Air; D000975:Antioxidants / Q000032:analysis*; D001272:Atmosphere; D015374:Biosensing Techniques / Q000379:methods*; D003545:Cysteine / Q000494:pharmacology; D008239:Lysine / Q000378:metabolism; D008715:Methionine / Q000378:metabolism; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000172:deficiency* / Q000378:metabolism
chemical_list: D000975:Antioxidants; D008715:Methionine; D013482:Superoxide Dismutase; D008239:Lysine; D003545:Cysteine; D000111:Acetylcysteine