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Genome Announcements Oct 2017Here, we report the draft genome of the Gram-negative, sulfate-reducing bacterium strain G11. Isolated from a rumen fluid enrichment, this culture has been a model...
Here, we report the draft genome of the Gram-negative, sulfate-reducing bacterium strain G11. Isolated from a rumen fluid enrichment, this culture has been a model syntrophic partner due to its metabolic flexibility. The assembly yielded a single circular chromosome of 3,414,943 bp and a 57% G+C content.
PubMed: 29074670
DOI: 10.1128/genomeA.01207-17 -
Scientific Reports Aug 2015The microbiome of dental clinic wastewater and its impact on mercury methylation remains largely unknown. Waste generated during dental procedures enters the sewer...
The microbiome of dental clinic wastewater and its impact on mercury methylation remains largely unknown. Waste generated during dental procedures enters the sewer system and contributes a significant fraction of the total mercury (tHg) and methyl mercury (MeHg) load to wastewater treatment facilities. Investigating the influence of geochemical factors and microbiome structure is a critical step linking the methylating microorganisms in dental wastewater (DWW) ecosystems. DWW samples from a dental clinic were collected over eight weeks and analyzed for geochemical parameters, tHg, MeHg and bacterio-toxic heavy metals. We employed bacterial fingerprinting and pyrosequencing for microbiome analysis. High concentrations of tHg, MeHg and heavy metals were detected in DWW. The microbiome was dominated by Proteobacteria, Actinobacteria, Bacteroidetes, Chloroflexi and many unclassified bacteria. Significant correlations were found between the bacterial community, Hg levels and geochemical factors including pH and the predicted total amount (not fraction) of neutral Hg-sulfide species. The most prevalent known methylators included Desulfobulbus propionicus, Desulfovibrio desulfuricans, Desulfovibrio magneticus and Geobacter sulfurreducens. This study is the first to investigate the impact of high loads of Hg, MeHg and other heavy metals on the dental clinic wastewater microbiome, and illuminates the role of many known and unknown sulfate-reducing bacteria in Hg methylation.
Topics: Dental Waste; Medical Waste Disposal; Methylation; Methylmercury Compounds; Microbiota; Mouth; Wastewater
PubMed: 26271452
DOI: 10.1038/srep12872 -
Journal of Biomedical Materials... Jul 2016Titanium and its aluminum and vanadium-free alloys have especially great potential for medical applications. Electrochemical surface modification improves their surface...
Titanium and its aluminum and vanadium-free alloys have especially great potential for medical applications. Electrochemical surface modification improves their surface bioactivity and stimulates osseointegration process. In this work, the effect of plasma electrolytic oxidation of the β-type alloy Ti-15Mo surface on its bioactivity is presented. Bioactivity of the modified alloy was investigated by immersion in simulated body fluid (SBF). Biocompatibility of the modified alloys were tested using human bone marrow stromal cells (hBMSC) and wild intestinal strains (DV/A, DV/B, DV/I/1) of Desulfovibrio desulfuricans bacteria. The particles of apatite were formed on the anodized samples. Human BMSC cells adhered well on all the examined surfaces and expressed ALP, collagen, and produced mineralized matrix as determined after 10 and 21 days of culture. When the samples were inoculated with D. desulfuricans bacteria, only single bacteria were visible on selected samples. There were no obvious changes in surface morphology among samples. Colonization and bacterial biofilm formation was observed on as-ground sample. In conclusion, the surface modification improved the Ti-15Mo alloy bioactivity and biocompatibility and protected surface against colonization of the bacteria. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 903-913, 2016.
Topics: Aged; Alloys; Bone Marrow Cells; Cell Adhesion; Desulfovibrio desulfuricans; Electrochemical Techniques; Female; Humans; Male; Materials Testing; Middle Aged; Stromal Cells; Surface Properties
PubMed: 25952109
DOI: 10.1002/jbm.b.33442 -
Chemosphere Jul 2023Heap leaching ionic rare earth tailings might be prone to nourish sulfate reducing bacteria (SRB), but the SRB community in terrestrial ecosystems, such as tailings, has...
Heap leaching ionic rare earth tailings might be prone to nourish sulfate reducing bacteria (SRB), but the SRB community in terrestrial ecosystems, such as tailings, has never been studied. This work was conducted to investigate the SRB communities in revegetated and bare tailings in Dingnan county, Jiangxi province, China, incorporating with indoor experiments to isolate SRB strain in bioremediation of Cd contamination. Significant increases in richness, accompanied by reductions in evenness and diversity, were found in the SRB community in revegetated tailings compared to bare tailings. At genus taxonomic level, two distinct dominant SRB were observed in samples from bare and revegetated tailings, with Desulfovibrio dominating in the former and Streptomyces dominating in the latter, respectively. A single SRB strain was screened out from the bare tailings (REO-01). The cell of REO-01 was rod-shaped and belonged to family Desulfuricans and genus Desulfovibrio. The Cd resistance of the strain was further examined, no changes in cell morphology were observed at 0.05 mM Cd, additionally, the atomic ratios of S, Cd, and Fe changed with the increase in Cd dosages, indicating FeS and CdS were produced simultaneously, XRD results further confirmed the production changed gradually from FeS to CdS with increasing Cd dosages from 0.05 to 0.2 mM. FT-IR analysis showed that functional groups containing amide, polysaccharide glycosidic linkage, hydroxyl, carboxy, methyl, phosphodiesters and sulfhydryl groups in extracellular polymeric substances (EPS) of REO-01 might have affinity with Cd. This study demonstrated the potential of a single SRB strain isolated from ionic rare earth tailings in bioremediation of Cd contamination.
Topics: Cadmium; Biodegradation, Environmental; Ecosystem; Spectroscopy, Fourier Transform Infrared; Sulfates; Desulfovibrio; Metals, Rare Earth
PubMed: 37023895
DOI: 10.1016/j.chemosphere.2023.138615 -
Materials (Basel, Switzerland) Jan 2019Biocides are frequently used to control sulfate-reducing bacteria (SRB) in biofouling. The increasing restrictions of environmental regulations and growing safety...
Biocides are frequently used to control sulfate-reducing bacteria (SRB) in biofouling. The increasing restrictions of environmental regulations and growing safety concerns on the use of biocides result in efforts to minimize the amount of biocide use and develop environmentally friendly biocides. In this study, the antimicrobial activity and corrosion inhibition effect of a low-toxic alternative biocide, benzyldimethyldodecylammonium chloride (BDMDAC), on a 304 stainless steel substrate immersed in a ()-inoculated medium was examined. Potentiodynamic polarization curves were used to analyze corrosion behavior. Biofilm formation and corrosion products on the surfaces of 304 stainless steel coupons were examined using scanning electron microscopy (SEM), energy-dispersive X-ray spectrum, and confocal laser scanning microscopy (CLSM). Results demonstrated that this compound exhibited satisfactory results against microbial corrosion by . The corrosion current density and current densities in the anodic region were lower in the presence of BDMDAC in the -inoculated medium. SEM and CLSM analyses revealed that the presence of BDMDAC mitigated formation of biofilm by .
PubMed: 30669421
DOI: 10.3390/ma12020307 -
Journal of Hazardous Materials Oct 2023This paper describes a unique molecular mechanism for the EPS-mediated synthesis of CdS QDs by sulfate-reducing bacteria (SRB) under carbon source-induced reinforcement....
This paper describes a unique molecular mechanism for the EPS-mediated synthesis of CdS QDs by sulfate-reducing bacteria (SRB) under carbon source-induced reinforcement. Under the induced by carbon sources (HCOONa, CHCOONa and CHO), there was a significant increase in EPS production of SRB, particularly in protein, and the capacity of Cd(II) adsorption was further enhanced. CdS QDs were extracellularly synthesized by adding S after Cd(II) adsorption. The results showed that CdS QDs were wrapped or adhered by EPS, and the most significant increase in Arg and Lys among basic amino acids in EPS after HCOONa-induced was 133.34% and 63.89%, respectively. This may serve as a biological template for QD synthesis, producing protein gels with a large number of microcavities and controlling the nucleation of CdS QDs. The highest yield of HCOONa-CdS was achieved after induction, with 23.59 g/g biomass per unit strain, which was 447.34% higher than that before induction and was at a high level in previous studies. The synthesized CdS QDs were uniform in size distribution and had higher luminescence activity and a larger specific surface area than those synthesized by the chemical synthesis route, provides a new idea for EPS treatment of heavy metal wastewater and metal biorecovery.
Topics: Cadmium; Desulfovibrio desulfuricans; Carbon; Metals, Heavy; Desulfovibrio
PubMed: 37499495
DOI: 10.1016/j.jhazmat.2023.132146 -
Revista Argentina de Microbiologia 2022Desulfovibrio spp. are strict anaerobes that are ubiquitous in nature. They can reside in the human or animal gastrointestinal tract and, as they are also environmental...
Desulfovibrio spp. are strict anaerobes that are ubiquitous in nature. They can reside in the human or animal gastrointestinal tract and, as they are also environmental bacteria, may be present in soil and water. They can persist asymptomatically in the intestine or behave as opportunistic pathogens associated with primary bacteremia and intraabdominal infections. Several Desulfovibrio spp. infections may be underestimated due to their slow growth rate and because many laboratories do not routinely perform anaerobic cultures. Simple tests such as motility detection on a fresh subculture, Gram stain to confirm cell morphology, presence of HS in SIM agar and production of a red fluorescence in alkaline pH under UV light would be indicative of Desulfovibrio spp. Here we report the case of Desulfovibrio desulfuricans bacteremia in a woman with clinical picture of abdominal sepsis due to gangrenous appendicitis with multiple organ failure.
Topics: Female; Humans; Desulfovibrio desulfuricans; Bacteremia; Intraabdominal Infections
PubMed: 35688718
DOI: 10.1016/j.ram.2022.05.002 -
Journal of the American Chemical Society Oct 2017[FeFe] hydrogenases catalyze proton reduction and hydrogen oxidation displaying high rates at low overpotential. Their active site is a complex cofactor consisting of a...
[FeFe] hydrogenases catalyze proton reduction and hydrogen oxidation displaying high rates at low overpotential. Their active site is a complex cofactor consisting of a unique [2Fe] subcluster ([2Fe]) covalently bound to a canonical [4Fe-4S] cluster ([4Fe-4S]). The [FeFe] hydrogenase from Desulfovibrio desulfuricans is exceptionally active and bidirectional. This enzyme features two accessory [4Fe-4S] clusters for exchanging electrons with the protein surface. A thorough understanding of the mechanism of this efficient enzyme will facilitate the development of synthetic molecular catalysts for hydrogen conversion. Here, it is demonstrated that the accessory clusters influence the catalytic properties of the enzyme through a strong redox interaction between the proximal [4Fe-4S] cluster and the [4Fe-4S] subcluster of the H-cluster. This interaction enhances proton-coupled electronic rearrangement within the H-cluster increasing the apparent pK of its one electron reduced state. This may help to sustain H production at high pH values. These results may apply to all [FeFe] hydrogenases containing accessory clusters.
Topics: Catalytic Domain; Desulfovibrio desulfuricans; Electron Spin Resonance Spectroscopy; Electrons; Hydrogen; Hydrogen-Ion Concentration; Hydrogenase; Iron; Iron-Sulfur Proteins; Oxidation-Reduction; Protons
PubMed: 28910086
DOI: 10.1021/jacs.7b08193 -
Chinese Medicine Oct 2022As a first-line chemotherapeutic agent, 5-fluorouracil (5-FU) exhibits many side effects, weakening its efficacy in cancer treatment. In this study, we hypothesize that...
BACKGROUND
As a first-line chemotherapeutic agent, 5-fluorouracil (5-FU) exhibits many side effects, weakening its efficacy in cancer treatment. In this study, we hypothesize that Poria cocos polysaccharides (PCP), a traditional Chinese herbal medicine with various bioactivities and prebiotic effects, might improve the therapeutic effect of 5-FU by restoring the homeostasis of the gut microenvironment and the commensal gut microflora.
METHODS
Apc mice were employed to evaluate the anti-cancer effect of 5-FU in conjunction with PCP treatment. Body weight and food consumption were monitored weekly. Polyp count was used to assess the anti-cancer effect of PCP and 5-FU. Expressions of mucosal cytokines and gut epithelial junction molecules were measured using qRT-PCR. 16S rRNA gene sequencing of fecal DNAs was used to evaluate the compositional changes of gut microbiota (GM). Transplantation of Lactobacillus johnsonii and Bifidobacterium animalis were performed to verify the prebiotic effects of PCP in improving the efficacy of 5-FU.
RESULTS
The results showed that PCP treatment alleviated the weight loss caused by 5-FU treatment and reduced the polyp burden in Apc mice. Additionally, PCP treatment eased the cytotoxic effects of 5-FU by reducing the expressions of pro-inflammatory cytokines, increasing the anti-inflammatory cytokines; and significantly improving the gut barriers by enhancing the tight junction proteins and associated adhesion molecules. Furthermore, 16S rRNA gene sequencing data showed that PCP alone or with 5-FU could stimulate the growth of probiotic bacteria (Bacteroides acidifaciens, Bacteroides intestinihominis, Butyricicoccus pullicaecorum, and the genera Lactobacillus, Bifidobacterium, Eubacterium). At the same time, it inhibited the growth of potential pathogens (e.g., Alistipes finegoldii, Alistipes massiliensis, Alistipes putredinis., Citrobacter spp., Desulfovibrio spp., and Desulfovibrio desulfuricans). Moreover, the results showed that transplantation of L.johnsonii and B.animalis effectively reduced the polyp burden in Apc mice being treated with 5-FU.
CONCLUSION
Our study showed that PCP could effectively improve the anti-cancer effect of 5-FU by attenuating its side effects, modulating intestinal inflammation, improving the gut epithelial barrier, and modulating the gut microbiota of Apc mice.
PubMed: 36192796
DOI: 10.1186/s13020-022-00667-8 -
Chemical Biology & Drug Design Feb 2021The development of gut microbiota-targeted small molecules represents a promising platform for the identification of new therapeutics based on the implication of human...
The development of gut microbiota-targeted small molecules represents a promising platform for the identification of new therapeutics based on the implication of human gut bacteria with different diseases. Bacterial trimethylamine (TMA)-lyase (CutC) is expressed in gut bacteria and catalyzes the conversion of choline to TMA. The association of elevated TMA production with various disorders has directed research efforts toward identification of CutC inhibitors. Herein, we introduce peptidomimetics as a promising toolbox for the discovery of CutC inhibitors. Our approach starts with screening a library of peptidomimetics for intestinal metabolic stability followed by in vitro CutC inhibition. Compound 5 was identified from this screening platform with IC value of 5.9 ± 0.6 μM for CutC inhibition. Unlike previously reported CutC inhibitors, compound 5 possessed universal CutC inhibitory activity in different bacterial strains. Molecular dynamics simulations suggested a plausible binding site and inhibition mechanism for compound 5. Therefore, compound 5 is a promising lead for further structural optimization in the search for CutC-targeted small molecules.
Topics: Bacteria; Bacterial Proteins; Binding Sites; Desulfovibrio desulfuricans; Enzyme Inhibitors; Gastrointestinal Microbiome; Humans; Inhibitory Concentration 50; Kinetics; Lyases; Methylamines; Molecular Docking Simulation; Peptidomimetics
PubMed: 32772476
DOI: 10.1111/cbdd.13775