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1

Peroxidase activity in the sulfate-reducing bacterium Desulfotomaculum acetoxidans DSM 771

100%
Pawlowska-Cwiek L.
Polish Journal of Microbiology
|
2010
|
tom 59
|
nr 4
Earlier research demonstrated the secretion of benzoate, which must be oxygenated to its 4-hydroxy derivative in order to be included in further sulfate uptake processes. The present study on Desulfotomaculum acetoxidans DSM 771 was designed to determine the activity and catalytic specificity of the enzyme (most probably peroxidase) catalyzing the hydroxylation of secreted benzoate. Peroxidase activity measured with ABTS (2,2'-azino-bis (3-ethylbenzathiazoline-6-sulfonic acid) during cultivation indicated the greatest activity on the third and thirteen days (3.4 and 2.3 nkat per ml sample respectively). The highest (0.7979) correlation coefficient was calculated between peroxidase activity and hydrogen peroxide levels. The cell walls from 3- and 13-day cultures were subjected to an isolation procedure, PIPES (piperazine-N,N'-bis (2-ethane-sulfonic acid) extract followed by preparative electrophoresis. The extracts of a~30 kDa band on the gel were analyzed by Western blotting and the membrane was stained with TMB (3,3',5,5'-tetramethylbenzidine-specific for the presence of peroxidase). This same protein was incubated for 6 h with benzoate, H₂O₂ Na₂SO₄. The product formed a complex with Fe³⁺ whose maximum absorption spectra (501.7 nm) corresponded with a ferric complex of synthetic 4-hydroxy-3-sulfo-benzoate. The H₂S level during the cultivation was higher in culture grown with 15.5 mM 4-hydroxy-3-sulfo-benzoate than in culture with lactate supplemented with 15.5 mM sulfate. The role of peroxidase in oxygen utilization and sulfate uptake is discussed.
2

Biotransformation of phosphogypsum in petroleum-refining wastewaters

88%
Wolicka D., Kowalski W.
Polish Journal of Environmental Studies
|
2006
|
tom 15
|
nr 2
Eleven isolates of sulphate-reducing bacteria (SRB) were isolated from soil contaminated with crude oil derivatives and petroleum-refining wastewaters and used to investigate the effectiveness of carbon reduction and biotransformation of phosphogypsum. One of the isolates (culture no. 10) was found to be very effective with 90% carbon reduction (measured as COD) and the simultaneous biotransformation of approximately 2.65g phosphogypsum/L in industrial petroleum-refining wastewaters.
3

Utilization of different carbon compounds by sulphate-reducing bacteria in mediums with phosphogypsum

88%
Wolicka D., Kowalski W.
Archiwum Ochrony Środowiska
|
2005
|
tom 31
|
nr 2
4

Sulphate-reducing bacteria, their properties and methods of elimination from groundwater

75%
Wargin A., Olanczuk-Neyman K., Skucha M.
Polish Journal of Environmental Studies
|
2007
|
tom 16
|
nr 4
639-644
In the Gdańsk region urban development and intensive take off have caused an increase in water ex­ploitation. As a consequence of the changes of hydrogeological conditions, a deterioration of chemical and bacteriological quality of water has been observed. Routine bacteriological quality control does not include some specific bacteria which are characteristic for the groundwater environment and can have negative in­fluence on the physical and chemical properties of water. Among such bacteria there are sulphate-reducing bacteria (SRB). In the paper frequency of SRB occurrence in raw water from Cretaceous and Quaternary formations and in treated water has been described. It has been proved that bacterial consortium isolated from groundwater show preference to sodium lactate as a main source of carbon and energy. SRB have a negative influence on organoleptic properties of water quality and the technical condition of distribution net, the water should be disinfected. It has been proved that non-reagent methods, like UV radiation and microfiltration, are effective for SRB elimination from groundwater.
5

Biotransformation of phosphogypsum on distillery decoctions [preliminary results]

75%
Wolicka D., Kowalski W.
Polish Journal of Microbiology
|
2006
|
tom 55
|
nr 2
The paper presents the activity of anaerobic bacterial communities isolated from soil polluted by aircraft fuel on distillery decoctions with phosphogypsum. The microorganisms were selected using the microcosms method, and then enriched on Postgate medium with ethanol. The isolated communities became the inoculum to establish a culture on potato and rye distillery decoctions. The obtained results show that a simultaneous removal of two industrial wastes such as phosphogypsum and distillery decoctions is possible. The introduction of a inoculation comprising a selected anaerobic bacterial community into the culture does not influence the increase of the biotransformation process efficiency.
6

Growth and antioxidant activity of Desulfotomaculum acetoxidans DSM 771 cultivated in acetate or lactate containing media

75%
Pawlowska-Cwiek L., Pado R.
Polish Journal of Microbiology
|
2007
|
tom 56
|
nr 3
Three independent 28 or 32-day stationary cultures of Desulfotomaculum acetoxidans DSM 771 strain were carried out under anoxic conditions in acetate or lactate-containing media. The acids were the sole carbon and energy sources in these media. During cultivation the turbidity (for calculation of cell division index) and hydrogen sulfide contents were determined in culture broth and reduced glutathione and protein concentrations were assayed in culture broth supernatant. In these three successive cultures, the bacterium initially grew much faster on lactate than on acetate. However, after two weeks of culture this difference disappeared and in fact the growth rate was higher on acetate than on lactate. The level of H₂S formed (product of the dissimilatory pathway of sulfate reduction) demonstrated that this pathway was more effective when lactate was a carbon source and the average H₂S concentration was from over 3-fold to about 9-fold greater in lactate than in acetate cultures. Also GSH (glutathione, product of the assimilatory sulfate reduction pathway) average level was about 2-fold higher in lactate-grown cultures. The high negative values of the correlation coefficients between GSH and O, levels, especially during the first 4 days of cultivation, indicate that GSH is a very important antioxidizing extracellular agent of D. acetoxidans. The rapid increase in GSH level, preceding the release of H₂S, indicates the metabolic priority of the assimilation pathway of sulfate reduction. For both carbon sources the highest coefficient of correlation was found between protein and H₂S levels. These results suggest that hydrogen sulfide is bound by proteins (which contain cysteinyl residues) secreted by D. acetoxidans cells. Indicated way of H,S bounding could result in its acccumulation. This coefficient of correlation increased gradually in the successive cultures. The ratio of H₂S concentration to protein concentration increased gradually in the successive cultures, too.
7

Geomicrobiological aspects of the oxidation of reduced sulfur compounds by photosynthesizing bacteria

75%
Borkowski A., Wolicka D.
Polish Journal of Microbiology
|
2007
|
tom 56
|
nr 1
The activity of photosynthesizing sulfur bacteria in a continuous culture was studied. The bacteria were isolated from the natural environment with the use of the Winogradski column. Isolated bacteria were cultured in synthetic medium and in the effluent from the column containig HS-. Sulphides, the main product of reduction of sulfates in phosphogypsum, were used by green sulfur bacteria in the photosynthetic column. Almost 70% reduction of the concentration of sulfides was observed. After the experiment, diffractometric methods where employed to analyze the sediment from the column.
8

Biotransformation of phosphogypsum by bacteria isolated from petroleum-refining wastewaters

75%
Wolicka D., Kowalski W., Boszczyk-Maleszak H.
Polish Journal of Microbiology
|
2005
|
tom 54
|
nr 2
The biotransformation of phosphogypsum in cultures of sulfate-reducing bacteria (SRB) isolated from crude petroleum-refining wastewaters or purified using activated sludge method was studied. Selection was with the microcosms method on Postgate and minimal medium with different carbon sources, Emerson medium and petroleum-refining wastewaters. Highest hydrogen sulfide production, in excess of 500 mg/L, was observed in culture of microorganisms isolated from purified petroleum-refining wastewaters in Postgate medium with phenol as sole carbon source. 76% phenol reduction with simultaneous biotransformation of 2.7g phosphogypsum/L (1350 mg SO₄/L) was obtained. The results regarding post-culture sediment indicated 66% utilization of phosphogypsum introduced into the culture (5 g/L), which reflects the active biotransformation of phosphogypsum by the community selected from the wastewaters.
9

Biotransformation of phosphogypsum by sulphate-reducing bacteria in media containing different zinc salts

75%
Rzeczycka M., Suszek A., Blaszczyk M.
Polish Journal of Environmental Studies
|
2004
|
tom 13
|
nr 2
The effect of zinc on the biotransformation of phosphogypsum, COD reduction and growth rate (μmax day-1) of an SRB community and Desulfotomaculum ruminis in media with sodium lactate or ethanol was examined. Depending on the form of zinc (Zn3(PO4)2 x 4H2O, ZnSO4 x7H2O, ZnCl2, Zn(NO3)2 x 6H2O) and its initial concentration (0-80 mg Zn2+/l) lower sulphate reduction and COD reduction was observed. The effect of Zn2+ also depended on the composition of the studied populations and carbon source in the medium. The lowest inhibition of specific growth rate was determined in cultures of the pure strain and in medium with zinc phosphate (with lactate or ethanol IC50=63 or 75 mg Zn2+/l, respectively) and the highest in cultures of sulphate-reducing bacterial communities in medium with zinc nitrate (with lactate or ethanol IC50= 35 or 20 mg Zn2+/l, respectively).
10

Simultaneous degradation of waste phosphogypsum and liquid manure from industrial pig farm by a mixed community of sulfate-reducing bacteria

63%
Rzeczycka M., Miernik A., Markiewicz Z.
Polish Journal of Microbiology
|
2010
|
tom 59
|
nr 4
The utilization of pig manure as a source of nutrients for the dissimilatory reduction of sulfates present in phosphogypsum was investigated. In both types of media used (synthetic medium and raw pig manure) increased utilization of sulfates with growing COD/SO₄²⁻ ratio in the medium was observed. The percent of sulfate reduction obtained in synthetic medium was from 18 to 99%, whereas the value for cultures set up in raw liquid manure was from 12% (at COD/SO₄²⁻ of 0.3) up to as high as 98% (at COD/SO₄²⁻ equal 3.80). Even with almost complete reduction of sulfates the percent of COD reduction did not exceed 55%. Based on the results obtained it was concluded that the effectiveness of removal of sulfates and organic matter by sulfate-reducing bacteria (SRB) depends to a considerable degree on the proportion between organic matter and sulfates in the purified wastewaters. The optimal COD/SO₄²⁻ ratio for the removal of organic matter was between 0.6 and 1.2 whereas the optimal ratio for the removal of sulfates was between 2.4 and 4.8.
11

Biotransformation of phosphogypsum in media containing different forms of nitrogen

63%
Rzeczycka M., Mycielski R., Kowalski W., Galazka M.
Acta Microbiologica Polonica
|
2001
|
tom 50
|
nr 3-4
281-289
12

The role of benzoate secreted by Desulfotomaculum acetoxidans DSM 771 in sulfate uptake

63%
Pawlowska-Cwiek L., Pado R.
Acta Biochimica Polonica
|
2005
|
tom 52
|
nr 4
This work was designed to find the cause of the delay in hydrogen sulfide dissimilation in Desulfotomaculum acetoxidans DSM 771, which is dependent on the sulfate uptake. This bacterium grown without addition of any aromatic compound was shown by spectrum analysis with the methylene method to contain hydroxy-benzoate derivatives. The presence of these compounds was confirmed by HPLC in fractions obtained from cell walls after 15 days of culture. The test with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt seemed to indicate the presence of peroxidase, which probably oxidized benzoate to its hydroxy derivatives. The test with 5-sulfo-salicylic acid proved the ability of the investigated strain to utilize arylsulfates and to reduce sulfate group to hydrogen sulfide. On the basis of the above data, we propose the following sequence of reactions: 1, benzoate secretion; 2, benzoate hydroxylation; 3, sulfonation of hydroxy-benzoate derivatives.
13

Participation of sulphate-reducing bacteria in biodegradation of organic matter in soils contaminated with petroleum products

63%
Wolicka D., Borkowski A.
Archiwum Ochrony Środowiska
|
2007
|
tom 33
|
nr 2
14

Isolation and evaluation of susceptibility to sulphasalazine of Desulfovibrio desulfuricans strains from the human digestive tract

63%
Dzierzewicz Z., Cwalina B., Gawlik B., Wilczok T., Gonciarz Z.
Acta Microbiologica Polonica
|
1997
|
tom 46
|
nr 2
15
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Microbially derived toxic gases as a possible cause of an episode of ill health in forestry

63%
Crook B., Cocker J., Gillanders E. M., Redmayne A. C., Jones K.
Annals of Agricultural and Environmental Medicine
|
1997
|
tom 04
|
nr 2
16
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

The occurrence and activity of sulphate-reducing bacteria in the bottom sediments of the Gulf of Gdańsk

63%
Mudryk Z. J., Podgorska B., Ameryk A., Bolalek J.
Oceanologia
|
2000
|
tom 42
|
nr 1
The paper presents the results of investigations concerning the number, distribution and physiological activity of sulphate-reducing bacteria (SRB) inhabiting the bottom sediments of the Gulf of Gdańsk. The numbers of this group of bacteria range between 0.76 × 103 and 1.27 × 104 cells per g wet sediment. The bacterial sulphate reduction rate in bottom sediments of this area of the Baltic Sea varies from 1.89 to 31.6 nM SO2− 4 g−1 24 h−1. The numbers of SRB and their physiological activity were subject to considerable seasonal fluctuations, maximum values being noted in summer (June) and minima in spring (April). A direct relationship has been found between the number of SRB and hydrogen sulphide concentrations; there is, however, no such relationship with reference to sulphate concentrations. The numbers and distributions of SRB demonstrated considerable variation in a depth profile of bottom sediments. SRB inhabiting the bottom sediments of the Gulf of Gdańsk were able to use three different organic substrates (lactate, acetate, propionate) as electron donors and as carbon and energy sources.
17

Effect of endotoxins isolated from Desulfovibrio desulfuricans soil and intestinal strain on the secretion of TNF-alpha by human mononuclear cells

63%
Weglarz L., Parfiniewicz B., Mertas A., Kondera-Anasz Z., Jaworska-Kik M., Dzierzewicz Z., Swiatkowska L.
Polish Journal of Environmental Studies
|
2006
|
tom 15
|
nr 4
Mononuclear cells play an important role in the regulation of microbe-induced inflammation, in part through their ability to secrete cytokines in response to microorganisms and their products. To evaluate the effects of Desulfovibrio desulfuricans-derived endotoxins on TNF-a induction, lipopolysaccharides (LPSs) isolated from soil and intestinal strain were used to stimulate peripheral blood mononuclear cells. The effect of these LPSs was assessed in comparison to that of LPSs from Escherichia coli, Salmonella minnesota and of lipid A from Salmonella minnesota. Level of TNF-a was measured by enzyme-linked immunosor­bent assay. D. desulfuricans LPSs at the highest dose (1000 ng/ml) displayed greater biological potency in inducing TNF-a secretion than other endotoxins used which indicates that these LPSs may act as a critical regulatory factor in bacteremia caused by these microorganisms.
18

Growth and activity of sulphate-reducing bacteria in media containing phosphogypsum and different sources of carbon

63%
Rzeczycka M., Blaszczyk M.
Polish Journal of Environmental Studies
|
2005
|
tom 14
|
nr 6
The possibility of using a mixed community of sulphate-reducing bacteria (SRB) for the biotransformation of phosphogypsum was examined. The greatest reduction of phosphogypsum (g/l) was determined in cultures with lactate (3.3), ethanol or casein (2.7), almost two-fold less in media with glucose or lactose and threefold less in medium with acetate. In media with lactate or ethanol growth inhibition (I = μ (μ max) was slight (I = 0.80 or 0.79) but much higher in the case of cultures with lactose (I=0.41), glucose (I=0.54), acetate or casein (I=0.62). In those cultures in which the concentration of sulphides was very high (about 600 mg HS⁻/l) and the concentration of acetic acid did not exceed 10 mg/l (e. g. in cultures with glucose), inhibition of SRB was mainly caused by H₂S. In cultures with transient low pH value (e. g. containing lactose or acetate) the factor causing stronger growth inhibition was acetic acid. A condition for obtaining high SRB activity in media with phosphogypsum and fermentable carbon sources is constant monitoring of the reaction of the medium and/or counteracting the accumulation of toxic concentrations of hydrogen sulphide and acetic acid.
19

Restriction profiles of plasmid DNA from wild strains of Desulfovibrio desulfuricans

63%
Dzierzewicz Z., Cwalina B., Szczerba J., Bednarek I., Mazurek U., Wilczok T.
Acta Biologica Cracoviensia. Series Botanica
|
2001
|
tom 43
One of many strategies of bacteria survival in a contaminated environment is plasmid-encoded resistance to toxic substances. D. desulfuricans wild strains isolated from soil and mud samples taken from contaminated sites were studied to identify plasmids in these bacteria and to examine their restriction profiles. The presence of plasmid DNA in all tested strains was demonstrated. Using B.stEII-digested DNA of phage λ. as the molecular standard, plasmid size was established at ~2.3 kbp. The restriction fragments obtained after cutting plasmid DNA with endonuclease HaeIII or AluI were better separated on gradient polyacrylamide gel than on homogeneous gel. Very high similarity between the fragment profiles was demonstrated, despite the different origins of the strains tested.
20

The uptake and accumulation of iron by the intestinal bacterium Desulfotomaculum acetoxidans DSM 771

51%
Pado R., Pawlowska-Cwiek L.
Folia Biologica
|
2005
|
tom 53
|
nr 1-2
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