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Journal of Applied Microbiology Nov 2006To study the influence of some metallic elements of stainless steel 304 (SS 304) on the development and activity of a sulfate-reducing bacterial biofilm, using as...
AIMS
To study the influence of some metallic elements of stainless steel 304 (SS 304) on the development and activity of a sulfate-reducing bacterial biofilm, using as comparison a reference nonmetallic material polymethylmethacrylate (PMMA).
METHODS AND RESULTS
Desulfovibrio desulfuricans biofilms were developed on SS 304 and on a reference nonmetallic material, PMMA, in a flow cell system. Steady-state biofilms were metabolically more active on SS 304 than on PMMA. Activity tests with bacteria from both biofilms at steady state also showed that the doubling time was lower for bacteria from SS 304 biofilms. The influence of chromium and nickel, elements of SS 304 composition, was also tested on a cellular suspension of Des. desulfuricans. Nickel decreased the bacterial doubling time, while chromium had no significant effect.
CONCLUSIONS
The following mechanism is hypothesized: a Des. desulfuricans biofilm grown on a SS 304 surface in anaerobic conditions leads to the weakening of the metal passive layer and to the dissolution in the bulk phase of nickel ions that have a positive influence on the sulfate-reducing bacteria metabolism. This phenomenon may enhance the biocorrosion process.
SIGNIFICANCE AND IMPACT OF THE STUDY
A better understanding of the interactions between metallic surfaces such as stainless steel and bacteria commonly implied in the corrosion phenomena which is primordial to fight biocorrosion.
Topics: Acetates; Bacterial Adhesion; Biofilms; Chromium; Corrosion; Desulfovibrio desulfuricans; Iron; Lactic Acid; Nickel; Polymethyl Methacrylate; Stainless Steel; Sulfates
PubMed: 17040232
DOI: 10.1111/j.1365-2672.2006.03001.x -
Transplantation Jul 2024Despite ongoing improvements to regimens preventing allograft rejection, most cardiac and other organ grafts eventually succumb to chronic vasculopathy, interstitial...
BACKGROUND
Despite ongoing improvements to regimens preventing allograft rejection, most cardiac and other organ grafts eventually succumb to chronic vasculopathy, interstitial fibrosis, or endothelial changes, and eventually graft failure. The events leading to chronic rejection are still poorly understood and the gut microbiota is a known driving force in immune dysfunction. We previously showed that gut microbiota dysbiosis profoundly influences the outcome of vascularized cardiac allografts and subsequently identified biomarker species associated with these differential graft outcomes.
METHODS
In this study, we further detailed the multifaceted immunomodulatory properties of protolerogenic and proinflammatory bacterial species over time, using our clinically relevant model of allogenic heart transplantation.
RESULTS
In addition to tracing longitudinal changes in the recipient gut microbiome over time, we observed that Bifidobacterium pseudolongum induced an early anti-inflammatory phenotype within 7 d, whereas Desulfovibrio desulfuricans resulted in a proinflammatory phenotype, defined by alterations in leukocyte distribution and lymph node (LN) structure. Indeed, in vitro results showed that B pseudolongum and D desulfuricans acted directly on primary innate immune cells. However, by 40 d after treatment, these 2 bacterial strains were associated with mixed effects in their impact on LN architecture and immune cell composition and loss of colonization within gut microbiota, despite protection of allografts from inflammation with B pseudolongum treatment.
CONCLUSIONS
These dynamic effects suggest a critical role for early microbiota-triggered immunologic events such as innate immune cell engagement, T-cell differentiation, and LN architectural changes in the subsequent modulation of protolerant versus proinflammatory immune responses in organ transplant recipients.
Topics: Heart Transplantation; Gastrointestinal Microbiome; Bifidobacterium; Graft Rejection; Animals; Male; Time Factors; Graft Survival; Dysbiosis; Mice, Inbred C57BL; Immunity, Innate; Immunomodulation; Phenotype; Probiotics; Lymph Nodes
PubMed: 38587506
DOI: 10.1097/TP.0000000000004939 -
Frontiers in Bioengineering and... 2022Sulfate-reducing bacteria (SRB) catalyse the dissimilatory reduction of sulfate to hydrogen sulfide using a wide range of small molecular weight organic compounds, and...
Sulfate-reducing bacteria (SRB) catalyse the dissimilatory reduction of sulfate to hydrogen sulfide using a wide range of small molecular weight organic compounds, and hydrogen, as electron donors. Here we report the effects of different combinations of small molecular weight alcohols on the performance and bacterial composition of a moderately low pH sulfidogenic bioreactor (pH 4.0-5.5) operated at 35°C in continuous flow mode. Ethanol alone and methanol or ethanol used in combination with glycerol were evaluated based on their equivalent amounts of carbon. Although evidenced that methanol was utilised as electron donor to fuel sulfidogenesis at pH 5.5, rates of sulfate reduction/sulfide production were negatively impacted when this alcohol was first introduced to the system, though these rates increased in subsequent phases as a result of adaptation of the microbial community. Further increased dosage of methanol again caused rates of sulfidogenesis to decrease. Methanol addition resulted in perturbations of the bioreactor microbial community, and species not previously detected were present in relatively large abundance, including the sulfate-reducer . Ethanol utilization was evidenced by the increase in rates of sulfidogenesis as the dosage of ethanol increased, with rates being highest when the bioreactor was fed with ethanol alone. Concentrations of acetate in the effluent liquor also increased (up to 8 mM) as a result of incomplete oxidation of ethanol. This alcohol continued to be used as the electron donor for sulfate reduction when the bioreactor pH was decreased incrementally (to pH 4.0), but rates of sulfidogenesis decreased. The relative abundance of diminished as the bioreactor pH was lowered, while that of the acidophilic increased. This study has shown that all three alcohols can be used to fuel microbial sulfidogenesis in moderately acidic liquors, though the cost-effectiveness, availability and toxicity to the microbial community will dictate the choice of substrate.
PubMed: 36032724
DOI: 10.3389/fbioe.2022.937987 -
European Journal of Biochemistry Dec 1984A soluble hydrogenase has been isolated from Desulfovibrio desulfuricans (strain Norway 4) grown on Postgate's medium. The enzyme differs significantly from a...
A soluble hydrogenase has been isolated from Desulfovibrio desulfuricans (strain Norway 4) grown on Postgate's medium. The enzyme differs significantly from a membrane-bound hydrogenase previously purified from the same organism grown on Starkey's medium. The enzyme consisted of two subunits of 56 kDa and 29 kDa compared with masses of 60 kDa and 27 kDa for the membrane-bound enzyme. Analysis of preparations of the soluble enzyme by various methods gave values of 5-10 iron atoms, 6 labile sulphur atoms and 0.45-0.8 nickel atom per molecule. The enzyme was unusual in that it contained selenium, in quantities equivalent to nickel. The highly purified active enzyme produced no electron-spin-resonance (ESR) signals in the oxidized state. ESR signals due to a [3Fe-xS] cluster and nickel were observed only in some of the less active fractions of the enzyme, demonstrating that neither of these ESR-detectable components is a prerequisite for hydrogenase activity. Treatment of D. desulfuricans (Norway) cells with EDTA released a minor fraction with hydrogenase activity, which might indicate the presence of a periplasmic enzyme.
Topics: Amino Acids; Chemical Phenomena; Chemistry; Chromatography, Gel; Desulfovibrio; Electron Spin Resonance Spectroscopy; Electrophoresis, Polyacrylamide Gel; Hydrogenase; Iron; Molecular Weight; Nickel; Selenium; Solubility
PubMed: 6096145
DOI: 10.1111/j.1432-1033.1984.tb08604.x -
Journal of Bacteriology Nov 1962Baker, F. D. (Western Reserve University, Cleveland, Ohio), H. R. Papiska, and L. Leon Campbell. Choline fermentation by Desulfovibrio desulfuricans. J. Bacteriol....
Baker, F. D. (Western Reserve University, Cleveland, Ohio), H. R. Papiska, and L. Leon Campbell. Choline fermentation by Desulfovibrio desulfuricans. J. Bacteriol. 84:973-978. 1962-Hayward and Stadtman pointed out that the organism they described as Vibrio cholinicus is closely related to Desulfovibrio desulfuricans. We have established that some strains of D. desulfuricans carry out the same fermentation of choline as does V. cholinicus. We have also shown that V. cholinicus carries out the sulfate-linked fermentation of lactate identical with that of D. desulfuricans. Both organisms have identical reduced cytochrome spectra, with peaks at 417 to 420, 525, and 553 mmu. V. cholinicus also contains the green pigment desulfoviridin, characteristic of D. desulfuricans, which in alkaline solution gives a red fluorescence at 365 mmu. Immunological data from cross-agglutination and absorption tests show that the two organisms have similar antigenic properties. Morphological, cultural, and biochemical studies have also demonstrated that V. cholinicus is indistinguishable from D. desulfuricans. Therefore, V. cholinicus should be regarded taxonomically as a strain of D. desulfuricans.
Topics: Antigens; Choline; Cytochromes; Desulfovibrio; Desulfovibrio desulfuricans; Fermentation; Hydrogensulfite Reductase; Nucleotidyltransferases; Sulfates; Sulfur; Transferases; Vibrio
PubMed: 13969140
DOI: 10.1128/jb.84.5.973-978.1962 -
Journal of Bacteriology Jul 1968The l-alanine dehydrogenase from cell-free extracts of Desulfovibrio desulfuricans was purified approximately 56-fold. The Michaelis constants for the substrates of the...
The l-alanine dehydrogenase from cell-free extracts of Desulfovibrio desulfuricans was purified approximately 56-fold. The Michaelis constants for the substrates of the amination reaction and the pH optima for the reactions catalyzed by this enzyme closely agree with those reported for other l-alanine dehydrogenases. Pyruvate was found to inhibit the amination reaction. The enzyme was absolutely specific for l-alanine and nicotinamide adenine dinucleotide. Its sensitivity to para-chloromecuribenzoate suggests that sulfhydryl groups may be necessary for enzymatic activity. These extracts also contained a nicotinamide adenine dinucleotide phosphate-specific glutamic dehydrogenase which was separated from the l-alanine dehydrogenase during purification.
Topics: Alanine; Amino Acid Oxidoreductases; Cell-Free System; Chemistry Techniques, Analytical; Chloromercuribenzoates; Chromatography; Desulfovibrio; Dialysis; Hydrogen-Ion Concentration; Kinetics; NAD; Pyruvates
PubMed: 4298732
DOI: 10.1128/jb.96.1.55-60.1968 -
Applied and Environmental Microbiology Sep 1996A comparison of cellular fatty acid profiles of Desulfovibrio desulfuricans DSM 642 and 14 wild strains of this species, isolated from two completely different...
A comparison of cellular fatty acid profiles of Desulfovibrio desulfuricans DSM 642 and 14 wild strains of this species, isolated from two completely different environments, soil and the human intestine, was carried out. All the D. desulfuricans strains grown on lactate and sulfate indicated the presence of considerable amounts of i-C15:0, i-C17:1 and C16:0. Although differences in the quantities of individual fatty acids present in each strain were clear in the group of soil strains (similarity, 67.6%), in contrast to almost identical fatty acid patterns (similarity, near 100%) in the intestinal strains, the results were variable within the limits acceptable for species demonstration. The higher similarity of the fatty acid profiles of intestinal strains may be a result of the similarity of biocenoses in the human digestive tract. The coefficients of variability of i-C17:1 and i-C15:0 (the major branched-chain fatty acids), as well as clustering of the investigated strains compared with strains described in the literature after plotting percentages of i-C17:1 fatty acid against i-C15:0 fatty acid, confirmed a certain heterogeneity of cellular fatty acid profiles within the group of soil strains, in contrast to almost ideal homogeneity within the group of intestinal isolates. Intestinal strains contained a higher ratio of saturated to unsaturated fatty acids (2.2 +/- 0.14) than did soil strains (1.6 +/- 0.2; in one case, 2.7). We propose that intestinal D. desulfovibrio bacteria should be assumed to be a highly homogeneous group and should be represented by the strain D. desulfuricans subsp. intestinus in collections of microbial cultures.
Topics: Desulfovibrio; Fatty Acids; Humans; Intestines; Soil Microbiology; Species Specificity
PubMed: 8795227
DOI: 10.1128/aem.62.9.3360-3365.1996 -
Applied Microbiology Jul 1966Growth of Desulfovibrio desulfuricans (API strain) was found to take place in an atmosphere of hydrogen on the agar surface of complex media, including yeast extract...
Growth of Desulfovibrio desulfuricans (API strain) was found to take place in an atmosphere of hydrogen on the agar surface of complex media, including yeast extract (Difco), and Trypticase Soy Agar (BBL) without any added reducing agents. For growth on a 2% yeast extract-agar surface in the absence of hydrogen (nitrogen atmosphere), sodium lactate was required in the medium. Growth on the surface of Trypticase Soy Agar (TSA) under nitrogen took place readily in the absence of an added hydrogen donor. A medium (TSA plus salts) is described based upon the addition of sodium lactate (4 ml per liter), magnesium sulfate (2 g per liter), and ferrous ammonium sulfate (0.05%) to TSA, which appears suitable for the isolation and growth of Desulfovibrio on the surface of agar plates in an atmosphere of hydrogen. Sodium lactate does not appear to be essential in this medium for good growth and sulfate reduction in a hydrogen atmosphere, but is essential in a nitrogen atmosphere. Growth of Desulfovibrio (hydrogen atmosphere) on the agar surface of media commonly used for its cultivation as well as on an inorganic medium containing bicarbonate as a source of carbon is poor and erratic unless inoculated (Desulfovibrio) plates of TSA plus salts are incubated in the same container with plates of these media. This stimulatory effect of incubation with inoculated plates of TSA plus salts medium appears to be due to as yet unidentified volatile material produced by D. desulfuricans when growing on this medium. Another volatile material, or possibly the identical material, appears to act similarly to a hydrogen donor.
Topics: Acetates; Agar; Bicarbonates; Culture Media; Desulfovibrio; Hydrogen; Iron; Magnesium; Nitrogen; Sulfates
PubMed: 5955798
DOI: 10.1128/am.14.4.529-534.1966 -
Applied and Environmental Microbiology Jul 1996High concentrations of total barium, ranging from 0.42 to 1.58 mg(middot)g(sup-1) (dry weight) were found in sludges of two sewage treatment plants near Florence, Italy....
High concentrations of total barium, ranging from 0.42 to 1.58 mg(middot)g(sup-1) (dry weight) were found in sludges of two sewage treatment plants near Florence, Italy. Barium concentrations in the suspended matter decreased as redox potential values changed from negative to positive. An anoxic sewage sludge sample was aerated, and 30% of the total barium was removed in 24 h. To demonstrate that barium was solubilized from barite by sulfate-reducing bacteria, a strain of Desulfovibrio desulfuricans was used to study the solubilization of barium from barite under laboratory conditions. During cell growth with different concentrations of barite from 0.01 to 0.3 g(middot)liter(sup-1) (the latter is the MIC) as the only source of sulfates in the cultures, the D. desulfuricans strain accumulated barium up to 0.58 (mu)g(middot)mg(sup-1) (dry weight). Three times the quantity of barium was dissolved by bacteria than in the uninoculated medium (control). The unexpectedly low concentration of soluble barium (1.2 mg of Ba(middot)liter(sup-1)) with respect to the quantity expected (109 mg of Ba(middot)liter(sup-1)), calculated on the basis of the free H(inf2)S evolved from the dissimilatory reduction of sulfate from barite, was probably due to the formation of other barium compounds, such as witherite (BaCO(inf3)) and the transient species barium sulfide (BaS). The D. desulfuricans strain, growing on barite, formed visible aggregates. Confocal microscopy analysis showed that aggregates consisted of bacteria and barite. After 3 days of incubation, several autofluorescent crystals surrounded by a dissolution halo were observed. The crystals were identified as BaS by comparison with the commercial compound.
PubMed: 16535353
DOI: 10.1128/aem.62.7.2398-2404.1996 -
Applied and Environmental Microbiology Feb 2000To explore the physiological role of tetraheme cytochrome c(3) in the sulfate-reducing bacterium Desulfovibrio desulfuricans G20, the gene encoding the preapoprotein was...
To explore the physiological role of tetraheme cytochrome c(3) in the sulfate-reducing bacterium Desulfovibrio desulfuricans G20, the gene encoding the preapoprotein was cloned, sequenced, and mutated by plasmid insertion. The physical analysis of the DNA from the strain carrying the integrated plasmid showed that the insertion was successful. The growth rate of the mutant on lactate with sulfate was comparable to that of the wild type; however, mutant cultures did not achieve the same cell densities. Pyruvate, the oxidation product of lactate, served as a poor electron source for the mutant. Unexpectedly, the mutant was able to grow on hydrogen-sulfate medium. These data support a role for tetraheme cytochrome c(3) in the electron transport pathway from pyruvate to sulfate or sulfite in D. desulfuricans G20.
Topics: Amino Acid Sequence; Base Sequence; Cloning, Molecular; Conjugation, Genetic; Cytochrome c Group; Desulfovibrio; Molecular Sequence Data; Mutation; Periplasm; Plasmids; Reverse Transcriptase Polymerase Chain Reaction; Sequence Analysis, DNA; Transcription, Genetic
PubMed: 10653734
DOI: 10.1128/AEM.66.2.671-677.2000