title: Metals tolerance in moderately thermophilic isolates from a spent copper sulfide heap, closely related to Acidithiobacillus caldus, Acidimicrobium ferrooxidans and Sulfobacillus thermosulfidooxidans.
abstract: Selective enrichments enabled the recovery of moderately thermophilic isolates with copper bioleaching ability from a spent copper sulfide heap. Phylogenetic and physiological characterization revealed that the isolates were closely related to Sulfobacillus thermosulfidooxidans, Acidithiobacillus caldus and Acidimicrobium ferrooxidans. While isolates exhibited similar physiological characteristics to their corresponding type strains, in general they displayed similar or greater tolerance of high copper, zinc, nickel and cobalt concentrations. Considerable variation was found between species and between several strains related to S. thermosulfidooxidans. It is concluded that adaptation to metals present in the bioleaching heap from which they were isolated contributed to but did not entirely explain high metals tolerances. Higher metals tolerance did not confer stronger bioleaching performance, suggesting that a physical, mineralogical or chemical process is rate limiting for a specific ore or concentrate.
authors.affiliation: Parker Centre for Integrated Hydrometallurgy Solutions, School of Biomedical Sciences, Curtin University of Technology, Bentley, WA, 6845, Australia. E.Watkin@curtin.edu.au
authors.forename: E L J
authors.initials: EL
authors.lastname: Watkin
authors.forename: S E
authors.initials: SE
authors.lastname: Keeling
authors.forename: F A
authors.initials: FA
authors.lastname: Perrot
authors.forename: D W
authors.initials: DW
authors.lastname: Shiers
authors.forename: M-L
authors.initials: ML
authors.lastname: Palmer
authors.forename: H R
authors.initials: HR
authors.lastname: Watling
mesh_terms: D042763:Acidithiobacillus / Q000145:classification / Q000187:drug effects / Q000235:genetics; D039903:Actinobacteria / Q000145:classification / Q000187:drug effects / Q000235:genetics; D001419:Bacteria / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D003300:Copper; D004269:DNA, Bacterial / Q000032:analysis / Q000302:isolation & purification; D006358:Hot Temperature; D019216:Metals, Heavy / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012987:Soil / Q000032:analysis; D012988:Soil Microbiology; D013440:Sulfides
chemical_list: D004269:DNA, Bacterial; D019216:Metals, Heavy; D012336:RNA, Ribosomal, 16S; D012987:Soil; D013440:Sulfides; D003300:Copper