title: Isolation and characterization of Ferroplasma thermophilum sp. nov., a novel extremely acidophilic, moderately thermophilic archaeon and its role in bioleaching of chalcopyrite.
abstract: OBJECTIVE
  To isolate Ferroplasma thermophilum L1(T) from a low pH environment and to understand its role in bioleaching of chalcopyrite.
  
  
  RESULTS
  Using serial dilution method, a moderately thermophilic and acidophilic ferrous iron-oxidizing archaeon, named L1(T), was isolated from a chalcopyrite-leaching bioreactor. The morphological, biochemical and physiological characteristics of strain L1(T) and its role in bioleaching of chalcopyrite were studied. Strain L1(T) was a nonmotile coccus that lacked cell wall. Strain L1(T) had a temperature optimum of 45 degrees C and the optimum pH for growth was 1.0. Strain L1(T) was capable of chemomixotrophic growth on ferrous iron and yeast extract. Results of fatty acid analysis, DNA-DNA hybridization, G+C content, and analysis based on 16S rRNA gene sequence indicated that strain L1(T) should be grouped in the genus Ferroplasma, and represented a new species, Ferroplasma thermophilum. Ferroplasma thermophilum in combination with Acidithiobacillus caldus and Leptospirillum ferriphilum could improve the copper dissolution in bioleaching of chalcopyrite.
  
  
  CONCLUSIONS
  A novel extremely acidophilic, moderately thermophilic archaeon isolated from a bioleaching reactor has been identified as F. thermophilum that played an important role in bioleaching of chalcopyrite at low pH.
  
  
  CONCLUSIONS
  This study contributes to understand the characteristics of F. thermophilum L1(T) and its role in bioleaching of sulfide ores.
authors.affiliation: School of Minerals Processing and Bioengineering, Central South University, Changsha, PR China.
authors.forename: H
authors.initials: H
authors.lastname: Zhou
authors.forename: R
authors.initials: R
authors.lastname: Zhang
authors.forename: P
authors.initials: P
authors.lastname: Hu
authors.forename: W
authors.initials: W
authors.lastname: Zeng
authors.forename: Y
authors.initials: Y
authors.lastname: Xie
authors.forename: C
authors.initials: C
authors.lastname: Wu
authors.forename: G
authors.initials: G
authors.lastname: Qiu
mesh_terms: D001105:Archaea / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D019149:Bioreactors; D052837:Chemoautotrophic Growth; D003300:Copper; D005798:Genes, Bacterial; D007218:Industrial Microbiology; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D010802:Phylogeny; D013045:Species Specificity
chemical_list: C012819:chalcopyrite; D003300:Copper