Resistance of Moderately Thermophilic Acidophilic Microorganisms to Ferric Iron Ions

Abstract:

Resistance of microorganisms predominating in biohydrometallurgical processes including bacteria of the genus Sulfobaсillus and archaea of the genus Acidiplasma to ferric iron ions was studied. Capabilities of the strains for growth and ferrous iron oxidation in the media containing high concentrations of ferric iron ions (of 250 to 1000 mM) were evaluated. Ferric iron ions significantly inhibited oxidative activity and growth of the studied microorganisms. It was revealed that bacteria of the genus Sulfobacillus were not able to oxidize ferrous iron actively when ferric iron concentration exceeded 500 mM, whereas archaea of the genus Acidiplasma completely oxidized ferrous iron in the medium containing 1000 mM of Fe³⁺. Growth of the microorganisms was inhibited by relatively low concentrations of ferric iron. Microorganisms did not grow in the medium containing more than 750 mM of Fe³⁺ and cells of all studied strains lysed in presence of high concentrations of ferric iron. It was shown, that archaea of the genus Acidiplasma of the family Ferroplasmaceae were more resistant to high concentrations of ferric iron than bacteria of the genus Sulfobacillus. The results obtained are important for understanding of the regularities of the formation of microbial communities performing technological processes.

• Periodical: Solid State Phenomena (Volume 262)
• Pages: 471-475
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.262.471
• Online since: August 2017
• Authors: Aleksandr Bulaev*
• Keywords: Acidiplasma, Acidophilic Microorganisms, Biohydrometallurgy, Ferric Sulfate, Sulfobacillus

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