Abstract
The effects of temperature, initial pH, and the concentrations of ammonium, phosphate, and heavy metals on the oxidation of thiosalts by an authentic strain of Thiobacillus thiooxidans (ATCC 8085) and by a mixed culture isolated from a base metal-processing mill effluent pond were studied. The optimum temperature was 30°C and the optimum initial pH was 3.75 for both cultures using thiosulfate and for the mixed culture using tetrathionate. T. thiooxidans ATCC 8085 did not oxidize tetrathionate. For a thiosalt concentration of 2,000 ppm (2,000 mg/liter), maximal rates of destruction occurred at concentrations of ammonium ion above 2 mg/liter and in the presence of 1 mg of phosphate per liter. Under optimal conditions, the rate of thiosulfate oxidation by the pure culture was 55 ± 3 mg/liter per h; the mixed culture oxidized thiosulfate at the rate of 40 ± 1 mg/liter per h and tetrathionate at the rate of 50 ± 2 mg/liter per h. Metal ions caused normal inhibition kinetics in the oxidation of thiosulfate by T. thiooxidans ATCC 8085. Ki values were calculated for cadmium (16 mg/liter), copper (0.46 mg/liter), lead (2 mg/liter), silver (3.1 mg/liter), and zinc (33 mg/liter). Only a slight additive effect was apparent in the presence of all of these metal ions. The mixed culture of thiosalt-oxidizing bacteria was less sensitive to heavy metal inhibition; the order of inhibition of thiosulfate oxidation was Cd < Zn < Pb < Ag < Cu, and that of tetrathionate oxidation was Zn < Cd < Pb < Ag < Cu.
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Selected References
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- Eccleston M., Kelly D. P. Oxidation kinetics and chemostat growth kinetics of Thiobacillus ferrooxidans on tetrathionate and thiosulfate. J Bacteriol. 1978 Jun;134(3):718–727. doi: 10.1128/jb.134.3.718-727.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LONDON J., RITTENBERG S. C. PATH OF SULFUR IN SULFIDE AND THIOSULFATE OXIDATION BY THIOBACILLI. Proc Natl Acad Sci U S A. 1964 Nov;52:1183–1190. doi: 10.1073/pnas.52.5.1183. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lundgren D. G., Silver M. Ore leaching by bacteria. Annu Rev Microbiol. 1980;34:263–283. doi: 10.1146/annurev.mi.34.100180.001403. [DOI] [PubMed] [Google Scholar]
- Silver M. Oxidation of elemental sulfur and sulfur compounds and CO2 fixation by Ferrobacillus ferrooxidans (Thiobacillus ferrooxidans). Can J Microbiol. 1970 Sep;16(9):845–849. doi: 10.1139/m70-142. [DOI] [PubMed] [Google Scholar]
- Tuovinen O. H., Kelly D. P. Studies on the growth of Thiobacillus ferrooxidans. V. Factors affecting growth in liquid culture and development of colonies on solid media containing inorganic sulphur compounds. Arch Microbiol. 1974 Jul 22;98(4):351–364. doi: 10.1007/BF00425295. [DOI] [PubMed] [Google Scholar]