Open AccessThe role of glutathione biosynthesis in heavy metal resistance in the fission yeast Schizosaccharomyces pombe
Author(s) -
Coblenz Anke,
Wolf Klaus
Publication year - 1994
Publication title -
fems microbiology reviews
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.91
H-Index - 212
eISSN - 1574-6976
pISSN - 0168-6445
DOI - 10.1111/j.1574-6976.1994.tb00103.x
Subject(s) - schizosaccharomyces pombe , glutathione , mutant , glutathione synthetase , biology , schizosaccharomyces , biochemistry , wild type , yeast , biosynthesis , mutagen , microbiology and biotechnology , enzyme , gene , dna
Plants and the fission yeast Schizosaccharomyces pombe synthesize small cadmium‐binding peptides, called phytochelatins, in response to cadmium. Derived from glutathione (GSH: λ‐Glu‐Cys‐Gly), they have the general structure (λ‐Glu‐Cys) n Gly, where n is 2–11. In order to study the biosynthesis of phytochelatins, we used the mutagen N ‐methyl‐ N ′‐nitro‐ N nitrosoguanidine (MNNG) to select mutants with a lowered GSH content. GSH‐deficient mutants show a Cd‐sensitive phenotype, whereas resistance to Cu is only slightly influenced. These Cd‐sensitive mutants contain 2–15% of the wild‐type GSH level. For three mutants a lowered activity of λ‐glutamylcysteine synthetase was measured. One of the mutants was transformed to Cd‐resistance and the complementing fragment was analyzed further. The complementing fragment hybridized with chromosome III. In the transformants, GSH content was restored up to wild‐type levels, whereas the activity of λ‐glutamylcysteine synthetase was significantly increased compared with the wild‐type. Possible mechanisms for Cd‐resistance in the transformants are discussed.