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1.
Copper dissolution from a sulfide ore (with covellite as the main copper phase) was investigated in cultures of Thiobacillus ferrooxidans or Thiobacillus thiooxidans and in abiotic controls. In unsupplemented media, T. ferrooxidans was more efficient than T. thiooxidans. In the presence of ferric iron, the dissolution of covellite was not significantly different in cultures inoculated with T. ferrooxidans or T. thiooxidans. However, the most extraction was found in T. thiooxidans cultures supplemented with ferrous sulfate. The first results were explained by the mechanism proposed by Schippers and Sand (Appl Envir Microbiol 65:319-321, 1999), which involves polysulfides and sulfur as intermediates. This mechanism was extended to explain the behavior of T. thiooxidans culture supplemented with ferrous iron. 相似文献
2.
Phenotypicpolymorphism of Thiobacillus ferrooxidansstrains isolated from various ecological niches was studied. The strains differed both in rates of growth and oxidation of Fe2+, S0, FeS2, and sulfide minerals contained in concentrate. Each strain, irrespective of its original environment, required a period of adaptation to a new substrate. Strains TFN-d, TFBk, TFO, and TFL-2, isolated from ores and concentrates rich in oxidizable substrates, showed an equal adaptation rate (five culture transfers) but differed in their adaptation efficiency. Strain TFV-1, isolated from low-grade ore and showing the lowest rates of growth and oxidation of all the substrates, required five culture transfers to adapt to S0and FeS2and seven culture transfers to adapt to the concentrate. It is concluded that the phenotypic properties of the strains correlate with their genotypic polymorphism and the environmental conditions under which their microevolution took place. 相似文献
3.
The cell envelope of a Sulfolobus-like microorganism has an arrayed hexagonal subunit structure, a double-layered cytoplasmic membrane, and a hollow periplasmic space between the plasma membrane and the outermost arrayed layer. A dense peptidoglycan layer outside the plasma membrane found in the case of Thiobacillus ferrooxidans was not seen. The cell envelope of a thermophile isolated from a leaching environment has a well-defined envelope with two well-stained layers distinclty seen. While the peptidoglycan layer is also not seen in this thermophile, a long flagellum similar to that in the case of T. ferrooxidans is present. The presence of pili in the Sulfolobus-like organism and its arrayed subunit cell envelope structure could account for the organism's selective attachment to sulfide phases in the leaching of low-grade ores. The observations of a well-defined cell envelope in the two thermophiles is consistent with the structure-function relationship previously established for T. ferrooxidans. 相似文献
4.
Summary In the presence of iron, which is always associated with natural sulphide ores, the percentages of copper dissolution in the bioleaching of covellite were 34 and 45 % when Thiobacillus thiooxidans and Thiobacillus ferrooxidans were used together and when an indirect bioleaching with attached bacteria was performed respectively. In the latter, the percentage of copper dissolution was still higher than the percentages obtained with pure cultures (36 % with a T. thiooxidans culture and 40 % with a T. ferrooxidans culture). 相似文献
5.
Beata Cwalina Tadeusz Wilczok Ludmila Weglarz Zofia Dzierżewicz 《Applied microbiology and biotechnology》1990,34(2):279-281
Summary The activities of enzymes involved in inorganic sulphur metabolism in crude, cell-free extracts of Thiobacillus ferrooxidans, strain F26-77 were determined during bacterial leaching of covellite and chalcopyrite. Increase in the specific activity of sulphide oxidase, thiosulphate oxidase and rhodanese during the leaching of both minerals was demonstrated. Simultaneously a decrease in the extraction rate of copper from the leached materials was observed.Offprint requests to: T. Wilczok 相似文献
6.
Summary The Ni2+ resistance of Thiobacillus ferrooxidans was enhanced by repeated culturing in medium containing Ni2+ and gradually increasing the Ni2+ concentration. The extraction of nickel sulfide was enhanced by the adapted strain following the direct leaching mechanism of the microorganism. 相似文献
7.
Bacterial leaching of a sulfide ore containing pyrite, chalcopyrite, and sphalerite was studied in shake flask experiments using Thiobacillus ferrooxidans and Thiobacillus thiooxidans strains isolated from mine sites. The Fe(2+)grown T. ferrooxidans isolates solubilized sphalerite preferentially over chalcopyrite leaching 7-10% Cu, 68-76% Zn, and 10-22% Fe from the ore in 18 days. The sulfur grown T. thiooxidans isolates leached Zn much more slowly and very little Fe, with a Cu-Zn extraction ratio twice the value obtained with T. ferrooxidans. The ore adapted T. ferrooxidans started solubilizing Cu and Zn without a lag period. The ore-adapted T. thiooxidans extracted Cu as well as T. ferrooxidans, but the extraction of Zn or Fe was still much slower in the low-phosphate medium, while in the high-phosphate medium it approached the value obtained with T. ferrooxidans. A high Cu-Zn extraction ratio of 0.34 was obtained with T. thiooxidans in the low phosphate medium. In the mixed-culture experiments with T. ferrooxidans and T. thiooxidans, the culture behaved as T. thiooxidans in the low-phosphate medium with a higher Cu-Zn extraction ratio and as T. ferrooxidans in the high-phosphate medium with a lower Cu-Zn extraction ratio. It is concluded that T. ferrooxidans and T. thiooxidans solubilize sulfide minerals by different mechanisms. 相似文献
8.
Beata Cwalina Ludmiła Węglarz Zofia Dzierzewicz Tadeusz Wilczok 《Applied microbiology and biotechnology》1988,28(1):100-102
Summary The leaching activity of five batches of Thiobacillus ferrooxidans, strain F26-77, cultivated under various conditions, towards elemental sulphur, ferrous ions, pyrite, covellite, chalcopyrite and sphalerite was studied. The activities of sulphite oxidase, thiosulphate oxidase and rhodanese were determined in crude, cell-free bacterial extracts. The effectiveness of leaching was directly correlated with the enzymic activity of the cultures. The results suggest that the activities of the enzymes metabolizing sulphur and its inorganic compounds in Thiobacillus ferrooxidans, or bacterial leaching activity on sulphur and sulphides, rather than the rate of oxidation of ferrous ions, should be taken as the criterion of usefulness for the leaching of sulphide minerals. 相似文献
9.
L. S. Gormely D. W. Duncan R. M. R. Branion K. L. Pinder 《Biotechnology and bioengineering》1975,17(1):31-49
A zinc sulfide concentrate was leached microbiologically by Thiobacillus ferrooxidans in a continuous stirred tank reactor. A model was developed to predict, the leaching kinetics when the bacterial growth rate was not limited by any substrate other than the zinc concentrate, and it was modified to explain the observed results. Stable steady sates were obtained over a range of dilution rates from 0.0171 to 0.1038 hr?1. Because a solid substrate was used, the specific growth rate of the bacaeria was not a unique function of the subastrate concentration, and conventional contnuous culture theory based on the Monod equation did not apply to this system. The leaching rates and bacterial growth rates were first order in mineral surface area cocentration. 相似文献
10.
The microbiological oxidation of ferrous iron in batch and continuous systems has been investigated in relation to uranium extraction from a low-grade ore by Thiobacillus ferrooxidans. The influence of the parameters, agitation, and aeration on oxygen saturation concentration, rate of oxygen mass transfer, and rate of ferrous iron oxidation was demonstrated. The kinetic values, Vmax and K were determined using an adapted Monod equation for different dilution rates and initial concentrations of ferrous iron. The power requirements for initial leaching conditions were also calculated. Uranium extraction as high as 68% has been realized during nine days of treatment. Regrinding the leach residue and its subsequent leaching yielded 87% uranium solubilization. 相似文献
11.
Mixotrophic growth of a Thiobacillus ferrooxidans strain is described. DNA moles percent guanine plus cytosine and homology determinations confirmed that the mixotrophically grown T. ferrooxidans cultures were not contaminated with heterotrophic Acidiphilium strains. 相似文献
12.
J. T. Pronk P. J. W. Meesters J. P. van Dijken P. Bos J. G. Kuenen 《Archives of microbiology》1990,153(4):392-398
Heterotrophic growth of the facultatively chemolithoautotrophic acidophile Thiobacillus acidophilus was studied in batch cultures and in carbon-limited chemostat cultures. The spectrum of carbon sources supporting heterotrophic growth in batch cultures was limited to a number of sugars and some other simple organic compounds. In addition to ammonium salts and urea, a number of amino acids could be used as nitrogen sources. Pyruvate served as a sole source of carbon and energy in chemostat cultures, but not in batch cultures. Apparently the low residual concentrations in the steady-state chemostat cultures prevented substrate inhibition that already was observed at 150 M pyruvate. Molar growth yields of T. acidophilus in heterotrophic chemostat cultures were low. The Y
max and maintenance coefficient of T. acidophilus grown under glucose limitation were 69 g biomass · mol–1 and 0.10 mmol · g–1 · h–1, respectively. Neither the Y
max nor the maintenance coefficient of glucose-limited chemostat cultures changed when the culture pH was increased from 3.0 to 4.3. This indicates that in T. acidophilus the maintenance of a large pH gradient is not a major energy-requiring process. Significant activities of ribulose-1,5-bisphosphate carboxylase were retained during heterotrophic growth on a variety of carbon sources, even under conditions of substrate excess. Also thiosulphate- and tetrathionate-oxidising activities were expressed under heterotrophic growth conditions. 相似文献
13.
A. Yokota M. Rodriguez Y. Yamada K. Imai D. Borowiak H. Mayer 《Archives of microbiology》1987,149(2):106-111
Lipopolysaccharides were isolated from two strains of Thiobacillus ferrooxidans and one strain each of Thiobacillus thiooxidans, Thiobacillus novellus and Thiobacillus sp. IFO 14570. Neutral sugars, 2-keto-3-deoxyoctonate, fatty acids and the rare 2,3-diamino-2,3-dideoxyglucose were detected in all lipopolysaccharides. Lipopolysaccharides of both T. ferrooxidans strains contained l-glycero-d-manno-heptose, whereas that of T. thiooxidans contained both l-glycero-d-manno-heptose and d-glycero-d-manno-heptose. On the other hand, heptoses were absent in lipopolysaccharides of T. novellus and Thiobacillus sp. IFO 14570. Lipid A of T. ferrooxidans and T. thiooxidans contained both glucosamine and 2,3-diamino-2,3-dideoxyglucose, in contrast, lipid A of T. novellus and the Thiobacillus sp. IFO 14570 most likely contain only 2,3-diamino-2,3-dideoxyglucose as backbone sugar. Deoxycholate polyacrylamide gel electrophoresis revealed S-type character for all lipopolysaccharides studied. The significance of the lipopolysaccharide composition for taxonomic and phylogenetic questions with regard to thiobacilli is discussed.Abbreviations DAG
2,3-diamino-2,3-dideoxyglucose
- DOC
sodium deoxycholate
- GC
gas-liquid chromatography
- GC/MS
gas-liquid chromatography/mass spectrometry
-
d,d-Heptose
d-glycero-d-manno-heptose
-
l,d-Heptose
l-glycero-d-manno-heptose
- KDO
2-keto-3-deoxyoctonate
- LPS
lipopolysaccharide
- 3-OH-14:0
3-hydroxy-tetradecanoic acid
- PAGE
polyacrylamide gel electrophoresis
- PCP
phenol-chloroform-petroleum ether 相似文献
14.
Rogier Meulenberg Jack T. Pronk Wim Hazeu Piet Bos J. Gijs Kuenen 《Archives of microbiology》1992,157(2):161-168
Oxidation of reduced sulphur compounds by Thiobacillus acidophilus was studied with cell suspensions from heterotrophic and mixotrophic chemostat cultures. Maximum substrate-dependent oxygen uptake rates and affinities observed with cell suspensions from mixotrophic cultures were higher than with heterotrophically grown cells. ph Optima for oxidation of sulphur compounds fell within the pH range for growth (pH 2–5), except for sulphite oxidation (optimum at pH 5.5). During oxidation of sulphide by cell suspensions, intermediary sulphur was formed. Tetrathionate was formed as an intermediate during aerobic incubation with thiosulphate and trithionate. Whether or not sulphite is an inter-mediate during sulphur compound oxidation by T. acidophilus remains unclear. Experiments with anaerobic cell suspensions of T. acidophilus revealed that trithionate metabolism was initiated by a hydrolytic cleavage yielding thiosulphate and sulphate. A hydrolytic cleavage was also implicated in the metabolism of tetrathionate. After anaerobic incubation of T. acidophilus with tetrathionate, the substrate was completely converted to equimolar amounts of thiosulphate, sulphur and sulphate. Sulphide- and sulphite oxidation were partly inhibited by the protonophore uncouplers 2,4-dinitrophenol (DNP) and carbonyl cyanide m-chlorophenylhydrazone (CCCP) and by the sulfhydryl-binding agent N-ethylmaleimide (NEM). Oxidation of elemental sulphur was completely inhibited by these compounds. Oxidation of thiosulphate, tetrathionate and trithionate was only slightly affected. The possible localization of the different enzyme systems involved in sulphur compound oxidation by T. acidophilus is discussed. 相似文献
15.
Thiobacillus acidophilus andT. ferrooxidans were separated by centrifugation on the basis of their cell density in Renografin gradients. For both species, growth history was the largest factor influencing cell density. Density was greatest forT. acidophilus andT. ferrooxidans grown with tetrathionate, followed byT. acidophilus grown with glucose.T. ferrooxidans grown with ferrous sulfate was the least dense.T. acidophilus was isolated from iron-grownT. ferrooxidans by separation in a Renografin gradient. Plasmid patterns ofT. acidophilus andT. ferrooxidans were used to confirm the separation of the two species in mixed gradients. 相似文献
16.
Abstract The purpose of the work was to characterize changes in surface textures of minerals during the biological leaching of a complex sulfide ore. The ore contained pyrrhotite (FeI_xS), pyrite (FeS2), sphalerite (ZnS), pentlandite [(Ni,Fe,Co)9S8], and chalcopyrite (CuFeS2). Several mixed cultures were initially screened using the ore material as the sole substrate. Shake flask leaching experiments showed no major differences among test cultures, which were all derived by enrichment techniques using environmental samples collected from a mine site. Leached pyrrhotite surfaces were invariably surrounded by a dark rim of elemental S. A reaction zone was also associated with leached sphalerite grains. Chemical analyses of leach solutions indicated that the relative ranking of biological leaching of the sulfide minerals was Zn > Ni > Co > Cu. Microscopic observations were in keeping with this rankin 相似文献
17.
Jörg Fischer Armin Quentmeier Susanne Kostka Regine Kraft C. G. Friedrich 《Archives of microbiology》1996,165(5):289-296
Hydrogenase of Thiobacillus ferrooxidans ATCC 19859 was purified from cells grown lithoautotrophically with 80% hydrogen, 8.6% carbon dioxide, and 11.4% air. Hydrogenase
was located in the 140,000 ×g supernatant in cell-free extracts. The enzyme was purified 7.3-fold after chromatography on Procion Red and Q-Sepharose with
a yield of 19%, resulting in an 85% pure preparation with a specific activity of 6.0 U (mg protein)–1. With native PAGE, a mol. mass of 100 and 200 kDa was determined. With SDS-PAGE, two subunits of 64 (HoxG) and of 34 kDa
(HoxK) were observed. Hydrogenase reacted with methylene blue and other artificial electron acceptors, but not with NAD. The
optimum of enzyme activity was at pH 9 and at 49° C. Hydrogenase contained 0.72 mol nickel and 6.02 mol iron per mol enzyme.
The relationship of the T. ferrooxidans hydrogenase to other proteins was examined. A 9.5-kb EcoRI fragment of T. ferrooxidans ATCC 19859 hybridized with a 2.2-kb XhoI fragment from Alcaligenes eutrophus encoding the membrane-bound hydrogenase. Antibodies against this enzyme did not react with the T. ferrooxidans hydrogenase in Western blot analysis. The N-terminal amino acid sequence (40 amino acids) of HoxK was 46% identical to that
of the hydrogen sensor HupU of Bradyrhizobium japonicum and 39% identical to that of the HupS subunit of the Desulfovibrio baculatus hydrogenase. The N-terminal sequence of 20 amino acids of HoxG of T. ferrooxidans was 83.3% identical to that of the 60-kDa subunit. HupL, of the hydrogenase of Anabaena sp. Sequences of ten internal peptides of HoxG were 50–100% identical to the respective sequences of HupL of the Anabaena sp. hydrogenase.
Received: 17 November 1995 / Accepted: 2 February 1996 相似文献
18.
Development of a Laboratory-Scale Leaching Plant for Metal Extraction from Fly Ash by Thiobacillus Strains 总被引:2,自引:0,他引:2
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Semicontinuous biohydrometallurgical processing of fly ash from municipal waste incineration was performed in a laboratory-scale leaching plant (LSLP) by using a mixed culture of Thiobacillus thiooxidans and Thiobacillus ferrooxidans. The LSLP consisted of three serially connected reaction vessels, reservoirs for a fly ash suspension and a bacterial stock culture, and a vacuum filter unit. The LSLP was operated with an ash concentration of 50 g liter−1, and the mean residence time was 6 days (2 days in each reaction vessel). The leaching efficiencies (expressed as percentages of the amounts applied) obtained for the economically most interesting metal, Zn, were up to 81%, and the leaching efficiencies for Al were up to 52%. Highly toxic Cd was completely solubilized (100%), and the leaching efficiencies for Cu, Ni, and Cr were 89, 64, and 12%, respectively. The role of T. ferrooxidans in metal mobilization was examined in a series of shake flask experiments. The release of copper present in the fly ash as chalcocite (Cu2S) or cuprite (Cu2O) was dependent on the metabolic activity of T. ferrooxidans, whereas other metals, such as Al, Cd, Cr, Ni, and Zn, were solubilized by biotically formed sulfuric acid. Chemical leaching with 5 N H2SO4 resulted in significantly increased solubilization only for Zn. The LSLP developed in this study is a promising first step toward a pilot plant with a high capacity to detoxify fly ash for reuse for construction purposes and economical recovery of valuable metals. 相似文献
19.
J. T. Pronk W. M. Meijer W. Hazeu J. P. van Dijken P. Bos J. G. Kuenen 《Applied microbiology》1991,57(7):2057-2062
A variety of acidophilic microorganisms were shown to be capable of oxidizing formate. These included Thiobacillus ferrooxidans ATCC 21834, which, however, could not grow on formate in normal batch cultures. However, the organism could be grown on formate when the substrate supply was growth limiting, e.g., in formate-limited chemostat cultures. The cell densities achieved by the use of the latter cultivation method were higher than cell densities reported for growth of T. ferrooxidans on ferrous iron or reduced sulfur compounds. Inhibition of formate oxidation by cell suspensions, but not cell extracts, of formate-grown T. ferrooxidans occurred at formate concentrations above 100 μM. This observation explains the inability of the organism to grow on formate in batch cultures. Cells grown in formate-limited chemostat cultures retained the ability to oxidize ferrous iron at high rates. Ribulose 1,5-bisphosphate carboxylase activities in cell extracts indicated that T. ferrooxidans employs the Calvin cycle for carbon assimilation during growth on formate. Oxidation of formate by cell extracts was NAD(P) independent. 相似文献
20.
Ferrous Iron and Sulfur Oxidation and Ferric Iron Reduction Activities of Thiobacillus ferrooxidans Are Affected by Growth on Ferrous Iron, Sulfur, or a Sulfide Ore 总被引:4,自引:3,他引:1
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Isamu Suzuki Travis L. Takeuchi Trin D. Yuthasastrakosol Jae Key Oh 《Applied microbiology》1990,56(6):1620-1626
Eight strains of Thiobacillus ferrooxidans (laboratory strains Tf-1 [= ATCC 13661] and Tf-2 [= ATCC 19859] and mine isolates SM-1, SM-2, SM-3, SM-4, SM-5, and SM-8) and three strains of Thiobacillus thiooxidans (laboratory strain Tt [= ATCC 8085] and mine isolates SM-6 and SM-7) were grown on ferrous iron (Fe2+), elemental sulfur (S0), or sulfide ore (Fe, Cu, and Zn). The cells were studied for their aerobic Fe2+ - and S0-oxidizing activities (O2 consumption) and anaerobic S0-oxidizing activity with ferric iron (Fe3+) (Fe2+ formation). Fe2+-grown T. ferrooxidans cells oxidized S0 aerobically at a rate of 2 to 4% of the Fe2+ oxidation rate. The rate of anaerobic S0 oxidation with Fe3+ was equal to the aerobic oxidation rate in SM-1, SM-3, SM-4, and SM-5, but was only one-half or less that in Tf-1, Tf-2, SM-2, and SM-8. Transition from growth on Fe2+ to that on S0 produced cells with relatively undiminished Fe2+ oxidation activities and increased S0 oxidation (both aerobic and anaerobic) activities in Tf-2, SM-4, and SM-5, whereas it produced cells with dramatically reduced Fe2+ oxidation and anaerobic S0 oxidation activities in Tf-1, SM-1, SM-2, SM-3, and SM-8. Growth on ore 1 of metal-leaching Fe2+-grown strains and on ore 2 of all Fe2+-grown strains resulted in very high yields of cells with high Fe2+ and S0 oxidation (both aerobic and anaerobic) activities with similar ratios of various activities. Sulfur-grown Tf-2, SM-1, SM-4, SM-6, SM-7, and SM-8 cultures leached metals from ore 3, and Tf-2 and SM-4 cells recovered showed activity ratios similar to those of other ore-grown cells. It is concluded that all the T. ferrooxidans strains studied have the ability to produce cells with Fe2+ and S0 oxidation and Fe3+ reduction activities, but their levels are influenced by growth substrates and strain differences. 相似文献