title: Nickel resistance in fission yeast associated with the magnesium transport system.
abstract: We isolated and characterized a nickel (Ni2+)-resistant mutant (GA1) of Schizosaccharomyces pombe. This mutant strain displayed resistance to both Ni2+ and Zn2+, but not to Cd2+, Co2+, and Cu2+. The growth rate of GA1 increased proportionally with increasing Mg2+ concentrations until 50 mM Mg2+. The GA1 mutation phenotype suggests a defect in Mg2+ uptake. Sequence analysis of the GA1 open reading frame (ORF) O13779, which is homologous to the prokaryotic and eukaryotic CorA Mg2+ transport systems, revealed a point mutation at codon 153 (ccc to acc) resulting in a Pro153Thr substitution in the N-terminus of the CorA domain. Our results provide novel genetic information about Ni2+ resistance in fission yeast. Specifically, that reducing Mg2+ influx through the CorA Mg2+ transport membrane protein confers Ni2+ resistance in S. pombe. We also report that Ni2+ ion detoxification of the fission yeast is related to histidine metabolism and pH.
authors.affiliation: Istanbul University, Faculty of Science, Department of Moleuclar Biology and Genetics, and Instanbul University Research and Application Center for Biotechnology and Genetic Engineering, 34118 Vezneciler, Istanbul, Turkey. atopal@Istanbul.edu.tr
authors.forename: Aysegul Topal
authors.initials: AT
authors.lastname: Sarikaya
authors.forename: Gokhan
authors.initials: G
authors.lastname: Akman
authors.forename: Guler
authors.initials: G
authors.lastname: Temizkan
mesh_terms: D001693:Biological Transport, Active; D001709:Biotechnology / Q000379:methods*; D004352:Drug Resistance, Microbial / Q000235:genetics; D008274:Magnesium / Q000378:metabolism*; D009532:Nickel / Q000378:metabolism / Q000494:pharmacology*; D012568:Schizosaccharomyces / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development
chemical_list: D009532:Nickel; D008274:Magnesium