GLUTATHIONE METABOLISM AND HEAVY-METAL DETOXIFICATION IN SCHIZOSACCHAROMYCES-POMBE - ISOLATION AND CHARACTERIZATION OF GLUTATHIONE-DEFICIENT, CADMIUM-SENSITIVE MUTANTS
GLUTATHIONE METABOLISM AND HEAVY-METAL DETOXIFICATION IN SCHIZOSACCHAROMYCES-POMBE - ISOLATION AND CHARACTERIZATION OF GLUTATHIONE-DEFICIENT, CADMIUM-SENSITIVE MUTANTS
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DOI：
10.1007/bf00336488
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发表时间：
1991-01-01
期刊：
影响因子：
2.5
通讯作者：
WOLF, K
中科院分区：
文献类型：
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作者：
GLAESER, H;COBLENZ, A;WOLF, K
通过对n -甲基-n′-硝基-n -亚硝基胍（MNNG）的抗性和对重金属镉（Cd）的敏感性，分离出60株谷胱甘肽缺乏突变体（gsh-）。53个突变体的谷胱甘肽含量低于野生型的5%。剩余谷胱甘肽含量与对MNNG的抗性、对Cd的敏感性和在最小培养基中的生长速率有关。gsh-、Cd敏感（Cd(s)）突变体也表现出对其他重金属的敏感性。野生型菌株，而不是gsh突变株，能够排出重金属，很可能是一种含硫化物的化合物。突变体不能排泄Cd和其他重金属，导致gsh突变体与野生型相比Cd积累增加。在60%的突变体中，谷胱甘肽缺乏很可能是由于谷胱甘肽合成酶（GS）的缺乏，另外40%的突变体似乎缺乏γ -谷氨酰半胱氨酸合成酶（GCS）。
Sixty glutathione-deficient mutants (gsh-) of Schizosaccharomyces pombe have been isolated by their resistance towards the mutagen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and their sensitivity to the heavy metal Cadmium (Cd). Fifty-three mutants show glutathione contents of less than 5% compared with the wild-type. The residual glutathione contents correlate with the resistance to MNNG, with the sensitivity to Cd and with the growth rate in minimal medium. The gsh-, Cd-sensitive (Cd(s)) mutants also show sensitivity to other heavy metals. Wild-type strains, but not the gsh- mutants, are able to excrete the heavy metal, very likely as a sulfide-containing compound. This inability of the mutants to excrete Cd and other heavy metals causes an increase in Cd accumulation in the gsh- mutants versus the wild-type. In 60% of the mutants the glutathione deficiency is very likely due to a deficiency in the enzyme glutathione synthetase (GS), the other 40% appear to be deficient in gamma-glutamyl-cysteine synthetase (GCS).