Kashevskii AV, Bulaev AG, Stom DI, Kalashnikova OB, Ramonova AA, Alferov SV, Topchiy IA, Zhdanova GO, Kupchinsky AB, Tolstoy MY, Petrova YY. Electrochemical Characteristics of the Oxidation of Sulfur- and Iron-Containing Compounds by Acidophilic Microorganisms.
Indian J Microbiol 2022;
62:558-568. [PMID:
36458215 PMCID:
PMC9705681 DOI:
10.1007/s12088-022-01034-9]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 07/26/2022] [Indexed: 11/05/2022] Open
Abstract
The electrochemical features of the interactions of sulfur- and iron-containing compounds (ferrous sulfate, elemental sulfur, pyrite tailings, cysteine, sodium thiosulfate) with a model acidophilic consortium, including the genera Leptospirillum, Sulfobacillus, Acidithiobacillus, Ferroplasma, and Acidiplasma, were studied. The method of cyclic voltammetry recorded redox processes at the electrode/solution interface in the presence of the studied sulfur- and iron-containing compounds. In general, the modeling consortium led to the intensification of these processes. The characteristics of the diffuse layer near the electrode/solution interface were studied using electrochemical impedance spectroscopy. The introduction of microorganisms and/or substrates into the supporting electrolyte led to a decrease in the slope and can be interpreted as evidence of their effect on the diffusion part of the double layer. Its contribution decreases in favor of ion transport. All this, in general, does not contradict the assumption of cell adsorption on the electrode surface. Confocal laser scanning microscopy confirmed this assumption and showed cell adhesion to the surface. The data obtained confirm the importance of bioelectrochemical processes of the studied group of microorganisms in biotechnological processes associated with the leaching of metals from sulfide ores.
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