Bánszky Luca, Simonics Tibor, Maráz Anna
Department of Microbiology and Biotechnology, Faculty of Food Science, Budapest Corvinus University, H-1118 Budapest, Somlói ut 14-16, Hungary.
J Gen Appl Microbiol. 2003 Oct;49(5):271-8. doi: 10.2323/jgam.49.271.
Selenate-resistant mutants were obtained from several strains of Schizosaccharomyces pombe. The obtained mutants all belonged to the same genetic complementation group. They were low in sulphate uptake activity and in ATP sulphurylase activity. They grew on medium containing sulphite, thiosulphate, cysteine or glutathione but not methionine as the sole source of sulphur. From these results, the mutants were concluded to carry mutations in the ATP sulphurylase gene. Inability of the mutants to utilize methionine as a sulphur source is rationalized by the absence of the reverse transsulphurylation pathway in this organism; wild type strains must utilize methionine as a sulphur source after it is degraded to give rise to sulphate.
从几种粟酒裂殖酵母菌株中获得了抗亚硒酸盐突变体。所获得的突变体均属于同一遗传互补群。它们的硫酸盐摄取活性和ATP硫酸化酶活性较低。它们能在以亚硫酸盐、硫代硫酸盐、半胱氨酸或谷胱甘肽作为唯一硫源的培养基上生长，但不能在以蛋氨酸作为唯一硫源的培养基上生长。根据这些结果，得出结论：这些突变体在ATP硫酸化酶基因中发生了突变。该生物体中不存在反向转硫途径，这解释了突变体无法利用蛋氨酸作为硫源的现象；野生型菌株必须在蛋氨酸降解产生硫酸盐后才能将其用作硫源。
