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Ivan Kushkevych - One of the best experts on this subject based on the ideXlab platform.
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Intestinal sulfate-reducing bacteria under the effect ofsalicylamides derivatives
2020Co-Authors: Ivan Kushkevych, Monika Vítězová, Peter Kollar, Josef JampílekAbstract:Sulfate-reducing bacteria (SRB) are most likely involved in both the initiation and maintenance of the inflammatory bowel disease (IBD), unfortunately present antibacterial chemotherapeutics used in the treatment of IBD have been ineffective. Thus, the antimicrobial activity of salicylamide derivatives on two different genera of intestinal SRB, Desulfovibrio and Desulfomicrobium was investigated. Six 2-(phenylcarbamoyl)phenyl N-[(benzyloxy)carbonyl]alkanoatesand three 2-hydroxy-N-[(2S)-1-oxo-1-(phenylamino)alkan-2-yl]benzamides showed MIC values in the range from 0.22 to 0.35 microM against Desulfovibrio piger Vib-7 and in the range from 0.27 to 8.52 microM against Desulfomicrobium sp. Rod-9, which is by two orders of magnitude lower compared with ciprofloxacin.
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The diversity of sulfate-reducing bacteria in the seven bioreactors
Archives of Microbiology, 2018Co-Authors: Ivan Kushkevych, Monika Vítězová, Jozef Kováč, Tomáš Vítěz, Milan BartosAbstract:Anaerobic technology has a wide scope of application in different areas such as manufacturing, food industry, and agriculture. Nowadays, it is mainly used to produce electrical and thermal energy from crop processing, solid waste treatment or wastewater treatment. More intensively, trend nowadays is usage of this technology biodegradable and biomass waste processing and biomethane or hydrogen production. In this paper, the diversities of sulfate-reducing bacteria (SRB) under different imputed raw material to the bioreactors were characterized. These diversities at the beginning of sampling and after cultivation were compared. Desulfovibrio, Desulfobulbus, and Desulfomicrobium genus as dominant among sulfate reducers in the bioreactors were detected. The Desulfobulbus species were dominant among other SRB genera before cultivation, but these bacteria were detected only in three out of the seven bioreactors after cultivation dominant.
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Antimicrobial effect of salicylamide derivatives against intestinal sulfate-reducing bacteria
Journal of Applied Biomedicine, 2016Co-Authors: Ivan Kushkevych, Milan Bartos, Peter Kollar, Ana Luisa Ferreira, Diogo Palma, Aida Duarte, Maria Manuel Lopes, Karel Pauk, Ales Imramovsky, Josef JampílekAbstract:Abstract Sulfate-reducing bacteria (SRB) are most likely involved in both the initiation and maintenance of inflammatory bowel disease (IBD); unfortunately present antibacterial chemotherapeutics used in the treatment of IBD have been ineffective. Thus, the antimicrobial activity of salicylamide derivatives against two different genera of intestinal SRB, Desulfovibrio and Desulfomicrobium , was investigated. Six 2-(phenylcarbamoyl)phenyl N -[(benzyloxy)carbonyl]alkanoates and three 2-hydroxy- N -[(2 S )-1-oxo-1-(phenylamino)alkan-2-yl]benzamides showed MIC values in the range from 0.22 to 0.35 μM against Desulfovibrio piger Vib-7 and in the range from 0.27 to 8.52 μM against Desulfomicrobium sp. Rod-9, while MIC values of ciprofloxacin were 41.2 μM and 39.3 μM. The highest potency against the two strains was observed for 4-chloro- N -{(2 S )-1-[(3,4-dichlorophenyl)amino]-3-methyl-1-oxobutan-2-yl}-2-hydroxybenzamide (MIC 0.22 μM and 0.27 μM). 4-Chloro-2-[(4-nitrophenyl)carbamoyl]phenyl (2 S )-2-{[(benzyloxy)carbonyl]amino}-3-methylbutanoate showed high activity against D. piger Vib-7 (MIC = 0.26 μM), while 4-chloro-2-[(4-methylphenyl)carbamoyl]phenyl (2 S )-2-[( tert -butoxycarbonyl)amino]-3-(1 H -indol-2-yl)propanoate expressed high activity against Desulfomicrobium sp. Rod-9 (MIC = 0.31 μM). Structure–activity relationships are discussed.
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activity of na k activated mg2 dependent atp hydrolase in the cell free extracts of the sulfate reducing bacteria desulfovibrio piger vib 7 and Desulfomicrobium sp rod 9
Acta Veterinaria Brno, 2015Co-Authors: Ivan Kushkevych, R V Fafula, Tomas Parak, Milan BartosAbstract:The aim of our work was to study Na+/K+-activated Mg2+-dependent ATPase activity in cell-free extracts of the sulfate-reducing bacteria Desulfovibrio piger Vib-7 and Desulfomicrobium sp. Rod-9 isolated from the human large intestine, and to carry out the kinetic analysis of the enzyme reaction. The maximum ATPase activity for both bacterial strains at +35C was determined. The highest activities of the studied enzyme in the cell-free extracts of D. piger Vib-7 at pH 7.0 and Desulfomicrobium sp. Rod-9 at pH 6.5 were measured. Based on experimental data, the analysis of kinetic properties of the ATP-hydrolase reaction by the studied bacteria was carried out. The enzyme activity, initial (instantaneous) reaction rate (V0) and maximum rate of the ATPase reaction (Vmax) was significantly higher in D. piger Vib-7 cells than in Desulfomicrobium sp. Rod-9. Michaelis constants (Km) of the enzyme reaction for both bacterial strains were determined.
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Activity of Na+/K+-activated Mg2+-dependent ATP hydrolase in the cell-free extracts of the sulfate-reducing bacteria Desulfovibrio piger Vib-7 and Desulfomicrobium sp. Rod-9
Acta Veterinaria Brno, 2015Co-Authors: Ivan Kushkevych, R V Fafula, Tomas Parak, Milan BartosAbstract:The aim of our work was to study Na + /K + -activated Mg 2+ -dependent ATPase activity in cellfree extracts of the sulfate-reducing bacteria Desulfovibrio piger Vib-7 and Desulfomicrobium sp. Rod-9 isolated from the human large intestine, and to carry out the kinetic analysis of the enzyme reaction. The maximum ATPase activity for both bacterial strains at +35 oC was determined. The highest activities of the studied enzyme in the cell-free extracts of D. piger Vib-7 at pH 7.0 and Desulfomicrobium sp. Rod-9 at pH 6.5 were measured. Based on experimental data, the analysis of kinetic properties of the ATP-hydrolase reaction by the studied bacteria was carried out. The enzyme activity, initial (instantaneous) reaction rate (V 0 ) and maximum rate of the ATPase reaction (Vmax) was significantly higher in D. piger Vib-7 cells than in Desulfomicrobium sp. Rod9. Michaelis constants (K m ) of the enzyme reaction for both bacterial strains were determined. ATPase activity, hydrogen sulfide, intestinal microbiocenosis, bowel diseases, ulcerative colitis Sulfate-reducing bacteria carry out the dissimilatory sulfate reduction during anaerobic respiration (Barton and Hamilton 2007). The final product of the sulfate reduction in the human intestine is hydrogen sulfide which is carcinogenic to its cells, and can cause inhibition of cytochrome oxidase, colonocytes oxidation of butyrate, destruction of epithelial cells, development of ulcers, and inflammation with subsequent development of colon cancer (Pitcher and Cummings 1996; Gibson et al. 1991; Cummings et al. 2003). The transport of sulfate ions and organic compounds in the cytoplasm of the bacterial cells occurs through active transport using ATP energy (Barton and Hamilton 2007). In this regard, it is very important to study the mechanisms of sulfate ions transport, enzymatic activity and kinetic properties of other ATP-dependent enzymes of sulfatereducing bacteria from human intestine. Plentiful data are available on the functions of biological membranes including the integral membrane protein ATP-dependent systems of transport ions (Lodish et al. 2000; Yuan et al. 2005; Tian et al. 2006). However, the ATPase activity of the sulfate-reducing bacteria Desulfovibrio piger and Desulfomicrobium sp. isolated from the human large intestine has not been studied yet. A comprehensive study of the functioning and role of Na + /K + -pump as a system of energy-dependent transport of different ions in the regulation of the dissimilatory sulfate reduction and accumulation of hydrogen sulfide will enable to form a holistic view on the participation of these systems in maintaining ion homeostasis of the sulfate-reducing bacteria cells.
David L Turner - One of the best experts on this subject based on the ideXlab platform.
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proton assisted two electron transfer in natural variants of tetraheme cytochromes from Desulfomicrobium sp
Journal of Biological Chemistry, 2004Co-Authors: Ilidio J Correia, Catarina M Paquete, Ana Varela Coelho, Claudia C Almeida, Teresa Catarino, Ricardo O Louro, Carlos Frazao, Ligia M Saraiva, Maria Armenia Carrondo, David L TurnerAbstract:Abstract The tetraheme cytochrome c3 isolated from Desulfomicrobium baculatum (DSM 1743)(Dsmb) was cloned, and the sequence analysis showed that this cytochrome differs in just three amino acid residues from the cytochrome c3 isolated from Desulfomicrobium norvegicum (Dsmn): (DsmnXXDsmb) Thr-37 → Ser, Val-45 → Ala, and Phe-88 → Tyr. X-ray crystallography was used to determine the structure of cytochrome c3 from Dsmb, showing that it is very similar to the published structure of cytochrome c3 from Dsmn. A detailed thermodynamic and kinetic characterization of these two tetraheme cytochromes c3 was performed by using NMR and visible spectroscopy. The results obtained show that the network of cooperativities between the redox and protonic centers is consistent with a synergetic process to stimulate the hydrogen uptake activity of hydrogenase. This is achieved by increasing the affinity of the cytochrome for protons through binding electrons and, reciprocally, by favoring a concerted two-electron transfer assisted by the binding of proton(s). The data were analyzed within the framework of the differences in the primary and tertiary structures of the two proteins, showing that residue 88, close to heme I, is the main cause for the differences in the microscopic thermodynamic parameters obtained for these two cytochromes c3. This comparison reveals how replacement of a single amino acid can tune the functional properties of energy-transducing proteins, so that they can be optimized to suit the bioenergetic constraints of specific habitats.
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nmr studies and redox titration of the tetraheme cytochrome c3 from Desulfomicrobium baculatum identification of the low potential heme
FEBS Journal, 1995Co-Authors: Isabel B Coutinho, David L Turner, Jean Legall, Antonio V XavierAbstract:: The tetraheme cytochromes c3 isolated from two strains of Desulfomicrobium baculatum were studied by monitoring the spectral changes undergone during redox titrations followed by 1H NMR. The evolution of the three-protein intensity signals at low field allowed the partial identification of the heme methyl resonances in the spectrum of the fully oxidized state. The chemical shift variation shown by the protons of the aromatic sidechains as well as of the substituents of the higher-potential heme HIII [Coutinho, I. B., Turner, D. L., LeGall, J. & Xavier, A. V. (1993) Biochem. J. 294, 899-908] yielded the assignment of the lower midpoint redox potential to heme HII in the three-dimensional structure. This cross-assignment is achieved by comparing the chemical shifts of the resonances in the spectra obtained at intermediate oxidation levels with the pseudocontact shifts predicted to arise from the three lower-potential hemes. The cross-assignment for the cytochromes from these two strains is different from that of the cytochromes from Desulfovibrio vulgaris and Desulfovibrio gigas.
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nmr studies and redox titration of the tetraheme cytochrome c3 from Desulfomicrobium baculatum
FEBS Journal, 1995Co-Authors: Isabel B Coutinho, David L Turner, Jean Legall, Antonio V XavierAbstract:The tetraheme cytochromes c3 isolated from two strains of Desulfomicrobium baculatum were studied by monitoring the spectral changes undergone during redox titrations followed by 1H NMR. The evolution of the three-proton intensity signals at low field allowed the partial identification of the heme methyl resonances in the spectrum of the fully oxidized state. The chemical shift variation shown by the protons of the aromatic sidechains as well as of the substituents of the higher-potential heme HIII [Coutinho, I. B., Turner, D. L., LeGall, J. & Xavier, A. V. (1993) Biochem. J. 294, 899–908] yielded the assignment of the lower midpoint redox potential to heme HII in the three-dimensional structure. This cross-assignment is achieved by comparing the chemical shifts of the resonances in the spectra obtained at intermediate oxidation levels with the pseudocontact shifts predicted to arise from the three lower-potential hemes. The cross-assignment for the cytochromes from these two strains is different from that of the cytochromes from Desulfovibrio vulgaris and Desulfovibrio gigas.
Antonio V Xavier - One of the best experts on this subject based on the ideXlab platform.
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nmr studies and redox titration of the tetraheme cytochrome c3 from Desulfomicrobium baculatum identification of the low potential heme
FEBS Journal, 1995Co-Authors: Isabel B Coutinho, David L Turner, Jean Legall, Antonio V XavierAbstract:: The tetraheme cytochromes c3 isolated from two strains of Desulfomicrobium baculatum were studied by monitoring the spectral changes undergone during redox titrations followed by 1H NMR. The evolution of the three-protein intensity signals at low field allowed the partial identification of the heme methyl resonances in the spectrum of the fully oxidized state. The chemical shift variation shown by the protons of the aromatic sidechains as well as of the substituents of the higher-potential heme HIII [Coutinho, I. B., Turner, D. L., LeGall, J. & Xavier, A. V. (1993) Biochem. J. 294, 899-908] yielded the assignment of the lower midpoint redox potential to heme HII in the three-dimensional structure. This cross-assignment is achieved by comparing the chemical shifts of the resonances in the spectra obtained at intermediate oxidation levels with the pseudocontact shifts predicted to arise from the three lower-potential hemes. The cross-assignment for the cytochromes from these two strains is different from that of the cytochromes from Desulfovibrio vulgaris and Desulfovibrio gigas.
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nmr studies and redox titration of the tetraheme cytochrome c3 from Desulfomicrobium baculatum
FEBS Journal, 1995Co-Authors: Isabel B Coutinho, David L Turner, Jean Legall, Antonio V XavierAbstract:The tetraheme cytochromes c3 isolated from two strains of Desulfomicrobium baculatum were studied by monitoring the spectral changes undergone during redox titrations followed by 1H NMR. The evolution of the three-proton intensity signals at low field allowed the partial identification of the heme methyl resonances in the spectrum of the fully oxidized state. The chemical shift variation shown by the protons of the aromatic sidechains as well as of the substituents of the higher-potential heme HIII [Coutinho, I. B., Turner, D. L., LeGall, J. & Xavier, A. V. (1993) Biochem. J. 294, 899–908] yielded the assignment of the lower midpoint redox potential to heme HII in the three-dimensional structure. This cross-assignment is achieved by comparing the chemical shifts of the resonances in the spectra obtained at intermediate oxidation levels with the pseudocontact shifts predicted to arise from the three lower-potential hemes. The cross-assignment for the cytochromes from these two strains is different from that of the cytochromes from Desulfovibrio vulgaris and Desulfovibrio gigas.
Isabel B Coutinho - One of the best experts on this subject based on the ideXlab platform.
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nmr studies and redox titration of the tetraheme cytochrome c3 from Desulfomicrobium baculatum identification of the low potential heme
FEBS Journal, 1995Co-Authors: Isabel B Coutinho, David L Turner, Jean Legall, Antonio V XavierAbstract:: The tetraheme cytochromes c3 isolated from two strains of Desulfomicrobium baculatum were studied by monitoring the spectral changes undergone during redox titrations followed by 1H NMR. The evolution of the three-protein intensity signals at low field allowed the partial identification of the heme methyl resonances in the spectrum of the fully oxidized state. The chemical shift variation shown by the protons of the aromatic sidechains as well as of the substituents of the higher-potential heme HIII [Coutinho, I. B., Turner, D. L., LeGall, J. & Xavier, A. V. (1993) Biochem. J. 294, 899-908] yielded the assignment of the lower midpoint redox potential to heme HII in the three-dimensional structure. This cross-assignment is achieved by comparing the chemical shifts of the resonances in the spectra obtained at intermediate oxidation levels with the pseudocontact shifts predicted to arise from the three lower-potential hemes. The cross-assignment for the cytochromes from these two strains is different from that of the cytochromes from Desulfovibrio vulgaris and Desulfovibrio gigas.
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nmr studies and redox titration of the tetraheme cytochrome c3 from Desulfomicrobium baculatum
FEBS Journal, 1995Co-Authors: Isabel B Coutinho, David L Turner, Jean Legall, Antonio V XavierAbstract:The tetraheme cytochromes c3 isolated from two strains of Desulfomicrobium baculatum were studied by monitoring the spectral changes undergone during redox titrations followed by 1H NMR. The evolution of the three-proton intensity signals at low field allowed the partial identification of the heme methyl resonances in the spectrum of the fully oxidized state. The chemical shift variation shown by the protons of the aromatic sidechains as well as of the substituents of the higher-potential heme HIII [Coutinho, I. B., Turner, D. L., LeGall, J. & Xavier, A. V. (1993) Biochem. J. 294, 899–908] yielded the assignment of the lower midpoint redox potential to heme HII in the three-dimensional structure. This cross-assignment is achieved by comparing the chemical shifts of the resonances in the spectra obtained at intermediate oxidation levels with the pseudocontact shifts predicted to arise from the three lower-potential hemes. The cross-assignment for the cytochromes from these two strains is different from that of the cytochromes from Desulfovibrio vulgaris and Desulfovibrio gigas.
Sandra Baena - One of the best experts on this subject based on the ideXlab platform.
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Colombian Andean thermal springs: reservoir of thermophilic anaerobic bacteria producing hydrolytic enzymes
Extremophiles, 2019Co-Authors: Carolina Rubiano-labrador, Carolina Díaz-cárdenas, Gina Lopez, Javier Gómez, Sandra BaenaAbstract:Anaerobic cultivable microbial communities in thermal springs producing hydrolytic enzymes were studied. Thermal water samples from seven thermal springs located in the Andean volcanic belt, in the eastern and central mountain ranges of the Colombian Andes were used as inocula for the growth and isolation of thermophilic microorganisms using substrates such as starch, gelatin, xylan, cellulose, Tween 80, olive oil, peptone and casamino acids. These springs differed in temperature (50–70 °C) and pH (6.5–7.5). The predominant ion in eastern mountain range thermal springs was sulphate, whereas that in central mountain range springs was bicarbonate. A total of 40 anaerobic thermophilic bacterial strains that belonged to the genera Thermoanaerobacter, Caloramator, Anoxybacillus, Caloranaerobacter, Desulfomicrobium, Geotoga, Hydrogenophilus, Desulfacinum and Thermoanaerobacterium were isolated. To investigate the metabolic potential of these isolates, selected strains were analysed for enzymatic activities to identify strains than can produce hydrolytic enzymes. We demonstrated that these thermal springs contained diverse microbial populations of anaerobic thermophilic comprising different metabolic groups of bacteria including strains belonging to the genera Thermoanaerobacter, Caloramator, Anoxybacillus, Caloranaerobacter, Desulfomicrobium, Geotoga, Hydrogenophilus, Desulfacinum and Thermoanaerobacterium with amylases, proteases, lipases, esterases, xylanases and pectinases; therefore, the strains represent a promising source of enzymes with biotechnological potential.
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Desulfomicrobium thermophilum sp nov a novel thermophilic sulphate reducing bacterium isolated from a terrestrial hot spring in colombia
Extremophiles, 2007Co-Authors: Marielaure Fardeau, Bernard Ollivier, Catherine Joulian, Sandra BaenaAbstract:A moderately thermophilic, sulphate-reducing bacterium, designated strain P6-2T, was isolated from a terrestrial hot spring located at a height of 2,500 m in the Andean region, Colombia (5°43′69″N, 73°6′10″W). Cells of strain P6-2T were rod-shaped, stained Gram-negative and were motile by means of a single polar flagellum. The strain grew lithotrophically with H2 as the electron donor and organotrophically on lactate, pyruvate, ethanol, malate, fumarate, n-propanol and succinate in the presence of sulphate as the terminal electron acceptor. Fumarate and pyruvate was fermented. Strain P6-2T grew optimally at 55°C (range 37–60°C), pH 6.6 (range 5.8–8.8) in the presence of 0.5% NaCl (range 0–4.5%) with lactate and sulphate and produced acetate, CO2 and H2S as the major end-products. Sulphate, sulphite and thiosulphate could be used as electron acceptors but not elemental sulphur or nitrate. The G + C content of the genomic DNA was 58.7 mol%. The 16S rRNA sequence analysis indicated that strain P6-2T was a member of the class Deltaproteobacteria, domain Bacteria with Desulfomicrobium baculatum being the closest relative (similarity value of 94%). Phylogeny of genes encoding α- and β-subunits of the dissimilatory sulphite reductase (dsrAB genes) supported its affiliation to members of the genus Desulfomicrobium. On the basis of this evidence, we propose to assign strain P6-2T as new species of the genus Desulfomicrobium, D. thermophilum sp. nov., with strain P6-2T as the type strain (= DSM 16697T = CCUG 49732T).