Nickel resistance in fission yeast associated with the magnesium transport system.
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.
Sarikaya
Aysegul Topal
AT
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
Akman
Gokhan
G
Temizkan
Guler
G
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
D009532:Nickel; D008274:Magnesium