is energetically advantageous compared to smelting and purifying. It also produces fewer toxic byproducts. Studies have shown that the inclusion of Ferroplasma thermophilum along with the bacteria Acidithiobacillus caldus and Leptospirillum ferriphilum can bioaugment the leaching process of chalcopyrite and increase the rate at which copper is recovered. Isolated Species Ferroplasma acidiphilum Ferroplasma acidiphilum has been shown to grow as a chemomixotroph and to grow synergistically with the acidophilic bacteria Leptospirillum ferriphilum. The strain Ferroplasma acidiphilum YT is a facultative anaerobe with all the required genes for arginine fermentation. Although it is unclear whether Ferroplasma acidiphilum YT uses its arginine fermentation pathway, the pathway itself is an ancient metabolism that traces back to the last universal common ancestor (LUCA) of the three domains of life. Ferroplasma acidarmanus Ferroplasma acidarmanus Fer1 was isolated from mine samples collected at Iron Mountain, California. Iron Mountain (CA) is a former mine that is known for its acid mine drainage (AMD) and heavy metal contamination. In addition to being acidophilic, F. acidarmanus Fer1 is highly resistant to both copper and arsenic. Ferroplasma cupricumulans (formerly Ferroplasma cyprexacervatum) In 2006 Ferroplasma cupricumulans was isolated from leachate solution collected from the Myanmar Ivanhoe Copper company (MICCL) mining site in Myanmar. It was noted to be the first slightly thermophilic member of the genus Ferroplasma. However, in 2009 a new genus of acidophilic, thermophilic archaea, Acidiplasma, was identified. It was proposed that, based on 16S rRNA similarity and DNA-DNA hybridization, be transferred to the genus Acidiplasma and renamed Acidiplasma cupricumulans. Ferroplasma thermophilum In 2008, Zhou, et al. described the isolation of the organism Ferroplasma thermophilum L1T from a chalcopyrite column reactor that was inoculated with acid mine drainage (AMD) from the Daye copper mine in China’s Hubei province. In aerobic conditions with low concentrations of yeast extract F. thermophilum grows by oxidizing ferrous iron. However, in anaerobic conditions F. thermophilum reduces ferric iron and sulfate. This makes F. thermophilum ecologically important for iron and sulfur cycling at pyrite-rich mine sites. See also List of Archaea genera References Further reading External links Archaea genera Metallotolerants Acidophiles Euryarchaeota