title: Molecular insight into extreme copper resistance in the extremophilic archaeon 'Ferroplasma acidarmanus' Fer1.
abstract: 'Ferroplasma acidarmanus' strain Fer1 is an extremely acidophilic archaeon involved in the genesis of acid mine drainage, and was isolated from copper-contaminated mine solutions at Iron Mountain, CA, USA. Here, the initial proteomic and molecular investigation of Cu(2+) resistance in this archaeon is presented. Analysis of Cu(2+) toxicity via batch growth experiments and inhibition of oxygen uptake in the presence of ferrous iron demonstrated that Fer1 can grow and respire in the presence of 20 g Cu(2+) l(-1). The Fer1 copper resistance (cop) loci [originally detected by Ettema, T. J. G., Huynen, M. A., de Vos, W. M. & van der Oost, J. Trends Biochem Sci 28, 170-173 (2003)] include genes encoding a putative transcriptional regulator (copY), a putative metal-binding chaperone (copZ) and a putative copper-transporting P-type ATPase (copB). Transcription analyses demonstrated that copZ and copB are co-transcribed, and transcript levels were increased significantly in response to exposure to high levels of Cu(2+), suggesting that the transport system is operating for copper efflux. Proteomic analysis of Fer1 cells exposed to Cu(2+) revealed the induction of stress proteins associated with protein folding and DNA repair (including RadA, thermosome and DnaK homologues), suggesting that 'Ferroplasma acidarmanus' Fer1 uses multiple mechanisms for resistance to high levels of copper.
authors.affiliation: School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
authors.forename: Craig
authors.initials: C
authors.lastname: Baker-Austin
authors.affiliation: School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Dopson
authors.affiliation: School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
authors.forename: Margaret
authors.initials: M
authors.lastname: Wexler
authors.affiliation: Department of Molecular Microbiology, John Innes Centre, Norwich NR4 7UH, UK.
authors.forename: R Gary
authors.initials: RG
authors.lastname: Sawers
authors.affiliation: Centre for Ecology, Evolution and Conservation, University of East Anglia, Norwich NR4 7TJ, UK.|School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
authors.forename: Philip L
authors.initials: PL
authors.lastname: Bond
mesh_terms: D003300:Copper / Q000494:pharmacology*; D019641:DNA, Archaeal / Q000235:genetics; D004352:Drug Resistance, Microbial; D019766:Genes, Archaeal; D008826:Microbial Sensitivity Tests; D019603:Thermoplasmales / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism
chemical_list: D019641:DNA, Archaeal; D003300:Copper