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Frontiers in Cellular and Infection... 2021Parkinson's disease (PD) is the most prevalent movement disorder known and predominantly affects the elderly. It is a progressive neurodegenerative disease wherein...
Parkinson's disease (PD) is the most prevalent movement disorder known and predominantly affects the elderly. It is a progressive neurodegenerative disease wherein α-synuclein, a neuronal protein, aggregates to form toxic structures in nerve cells. The cause of Parkinson's disease (PD) remains unknown. Intestinal dysfunction and changes in the gut microbiota, common symptoms of PD, are evidently linked to the pathogenesis of PD. Although a multitude of studies have investigated microbial etiologies of PD, the microbial role in disease progression remains unclear. Here, we show that Gram-negative sulfate-reducing bacteria of the genus may play a potential role in the development of PD. Conventional and quantitative real-time PCR analysis of feces from twenty PD patients and twenty healthy controls revealed that all PD patients harbored bacteria in their gut microbiota and these bacteria were present at higher levels in PD patients than in healthy controls. Additionally, the concentration of species correlated with the severity of PD. bacteria produce hydrogen sulfide and lipopolysaccharide, and several strains synthesize magnetite, all of which likely induce the oligomerization and aggregation of α-synuclein protein. The substances originating from bacteria likely take part in pathogenesis of PD. These findings may open new avenues for the treatment of PD and the identification of people at risk for developing PD.
Topics: Aged; Bacteria; Desulfovibrio; Humans; Neurodegenerative Diseases; Parkinson Disease; alpha-Synuclein
PubMed: 34012926
DOI: 10.3389/fcimb.2021.652617 -
Scientific Reports Aug 2017Microbial electrosynthesis is a renewable energy and chemical production platform that relies on microbial cells to capture electrons from a cathode and fix carbon. Yet...
Microbial electrosynthesis is a renewable energy and chemical production platform that relies on microbial cells to capture electrons from a cathode and fix carbon. Yet despite the promise of this technology, the metabolic capacity of the microbes that inhabit the electrode surface and catalyze electron transfer in these systems remains largely unknown. We assembled thirteen draft genomes from a microbial electrosynthesis system producing primarily acetate from carbon dioxide, and their transcriptional activity was mapped to genomes from cells on the electrode surface and in the supernatant. This allowed us to create a metabolic model of the predominant community members belonging to Acetobacterium, Sulfurospirillum, and Desulfovibrio. According to the model, the Acetobacterium was the primary carbon fixer, and a keystone member of the community. Transcripts of soluble hydrogenases and ferredoxins from Acetobacterium and hydrogenases, formate dehydrogenase, and cytochromes of Desulfovibrio were found in high abundance near the electrode surface. Cytochrome c oxidases of facultative members of the community were highly expressed in the supernatant despite completely sealed reactors and constant flushing with anaerobic gases. These molecular discoveries and metabolic modeling now serve as a foundation for future examination and development of electrosynthetic microbial communities.
Topics: Acetates; Acetobacterium; Bioelectric Energy Sources; Campylobacteraceae; Carbon Dioxide; Desulfovibrio; Electricity; Electrodes; Electron Transport; Gene Expression Profiling; Genome, Bacterial; Metabolic Networks and Pathways
PubMed: 28827682
DOI: 10.1038/s41598-017-08877-z -
FEMS Microbiology Ecology Feb 2022Despite hostile environmental conditions, microbial communities have been found in µL-sized water droplets enclosed in heavy oil of the Pitch Lake, Trinidad. Some...
Despite hostile environmental conditions, microbial communities have been found in µL-sized water droplets enclosed in heavy oil of the Pitch Lake, Trinidad. Some droplets showed high sulfate concentrations and surprisingly low relative abundances of sulfate-reducing bacteria in a previous study. Hence, we investigated here whether sulfate reduction might be inhibited naturally. Ion chromatography revealed very high formate concentrations around 2.37 mM in 21 out of 43 examined droplets. Since these concentrations were unexpectedly high, we performed growth experiments with the three sulfate-reducing type strains Desulfovibrio vulgaris, Desulfobacter curvatus, and Desulfococcus multivorans, and tested the effects of 2.5, 8, or 10 mM formate on sulfate reduction. Experiments demonstrated that 8 or 10 mM formate slowed down the growth rate of D. vulgaris and D. curvatus and the sulfate reduction rate of D. curvatus and D. multivorans. Increasing formate concentrations delayed the onsets of growth and sulfate reduction of D. multivorans, which were even inhibited completely while formate was added constantly. Contrary to previous studies, D. multivorans was the only organism capable of formate consumption. Our study suggests that formate accumulates in the natural environment of the water droplets dispersed in oil and that such levels are very likely inhibiting sulfate-reducing microorganisms.
Topics: Desulfovibrio; Formates; Microbiota; Oxidation-Reduction; Sulfates
PubMed: 35040992
DOI: 10.1093/femsec/fiac003 -
PLoS Genetics Feb 2020Many species of bacteria can manufacture materials on a finer scale than those that are synthetically made. These products are often produced within intracellular... (Review)
Review
Many species of bacteria can manufacture materials on a finer scale than those that are synthetically made. These products are often produced within intracellular compartments that bear many hallmarks of eukaryotic organelles. One unique and elegant group of organisms is at the forefront of studies into the mechanisms of organelle formation and biomineralization. Magnetotactic bacteria (MTB) produce organelles called magnetosomes that contain nanocrystals of magnetic material, and understanding the molecular mechanisms behind magnetosome formation and biomineralization is a rich area of study. In this Review, we focus on the genetics behind the formation of magnetosomes and biomineralization. We cover the history of genetic discoveries in MTB and key insights that have been found in recent years and provide a perspective on the future of genetic studies in MTB.
Topics: Bacterial Proteins; Biomineralization; DNA Transposable Elements; Desulfovibrio; Ferrosoferric Oxide; Genes, Bacterial; Magnetosomes; Magnetospirillum; Metal Nanoparticles; Mutagenesis; Mutation
PubMed: 32053597
DOI: 10.1371/journal.pgen.1008499 -
New Biotechnology Dec 2022A range of Desulfovibrio spp. can reduce metal ions to form metallic nanoparticles that remain attached to their surfaces. The bioreduction of palladium (Pd) has been...
A range of Desulfovibrio spp. can reduce metal ions to form metallic nanoparticles that remain attached to their surfaces. The bioreduction of palladium (Pd) has been given considerable attention due to its extensive use in areas of catalysis and electronics and other technological domains. In this study we report, for the first time, evidence for Pd(II) reduction by the highly corrosive Desulfovibrio ferrophilus IS5 strain to form surface attached Pd nanoparticles, as well as rapid formation of Pd(0) coated microbial nanowires. These filaments reached up to 8 µm in length and led to the formation of a tightly bound group of interconnected cells with enhanced ability to attach to a low carbon steel surface. Moreover, when supplied with high concentrations of Pd (≥ 100 mmol Pd(II) g dry cells), both Desulfovibrio desulfuricans and D. ferrophilus IS5 formed bacteria/Pd hybrid porous microstructures comprising millions of cells. These three-dimensional structures reached up to 3 mm in diameter with a dose of 1200 mmol Pd(II) g dry cells. Under suitable hydrodynamic conditions during reduction, two-dimensional nanosheets of Pd metal were formed that were up to several cm in length. Lower dosing of Pd(II) for promoting rapid synthesis of metal coated nanowires and enhanced attachment of cells onto metal surfaces could improve the efficiency of various biotechnological applications such as microbial fuel cells. Formation of biologically stimulated Pd microstructures could lead to a novel way to produce metal scaffolds or nanosheets for a wide variety of applications.
Topics: Palladium; Desulfovibrio desulfuricans; Desulfovibrio; Catalysis
PubMed: 36396027
DOI: 10.1016/j.nbt.2022.11.001 -
Research in Microbiology 2020Mercury methylation converts inorganic mercury into the toxic methylmercury, and the consequences of this transformation are worrisome for human health and the...
Mercury methylation converts inorganic mercury into the toxic methylmercury, and the consequences of this transformation are worrisome for human health and the environment. This process is performed by anaerobic microorganisms, such as several strains related to Pseudodesulfovibrio and Desulfovibrio genera. In order to provide new insights into the molecular mechanisms of mercury methylation, we performed a comparative genomic analysis on mercury methylators and non-methylators from (Pseudo)Desulfovibrio strains. Our results showed that (Pseudo)Desulfovibrio species are phylogenetically and metabolically distant and consequently, these genera should be divided into various genera. Strains able to perform methylation are affiliated with one branch of the phylogenetic tree, but, except for hgcA and hgcB genes, no other specific genetic markers were found among methylating strains. hgcA and hgcB genes can be found adjacent or separated, but proximity between those genes does not promote higher mercury methylation. In addition, close examination of the non-methylator Pseudodesulfovibrio piezophilus C1TLV30 strain, showed a syntenic structure that suggests a recombination event and may have led to hgcB depletion. The genomic analyses identify also arsR gene coding for a putative regulator upstream hgcA. Both genes are cotranscribed suggesting a role of ArsR in hgcA expression and probably a role in mercury methylation.
Topics: Bacterial Proteins; Desulfovibrio; Desulfovibrionaceae; Gene Expression Regulation, Bacterial; Genome, Bacterial; Mercury; Methylation; Phylogeny
PubMed: 31655199
DOI: 10.1016/j.resmic.2019.10.003 -
Molecules (Basel, Switzerland) May 2023A story going back almost 40 years is presented in this manuscript. This is a different and more challenging way of reporting my research and I hope it will be useful to... (Review)
Review
A story going back almost 40 years is presented in this manuscript. This is a different and more challenging way of reporting my research and I hope it will be useful to and target a wide-ranging audience. When preparing the manuscript and collecting references on the subject of this paper-aldehyde oxidoreductase from -I felt like I was travelling back in time (and space), bringing together the people that have contributed most to this area of research. I sincerely hope that I can give my collaborators the credit they deserve. This study is not presented as a chronologic narrative but as a grouping of topics, the development of which occurred over many years.
Topics: Humans; Aldehyde Oxidoreductases; Desulfovibrio gigas; Desulfovibrio; Molybdenum; Aldehyde Dehydrogenase
PubMed: 37241969
DOI: 10.3390/molecules28104229 -
Journal of Clinical Microbiology Aug 2005Seventeen human clinical isolates representing four species of Desulfovibrio were characterized using 16S rRNA gene sequences and tests for catalase, indole, nitrate,... (Comparative Study)
Comparative Study
Seventeen human clinical isolates representing four species of Desulfovibrio were characterized using 16S rRNA gene sequences and tests for catalase, indole, nitrate, bile, urease, formate-fumarate stimulation, desulfoviridin, motility, and hydrogen sulfide production, plus susceptibility to antimicrobial agents. Eighty additional strains representing 10 phenotypically similar genera (Bilophila, Selenomonas, Capnocytophaga, Campylobacter, Bacteroides, Sutterella, Anaerobiospirillum, Dialister, Veillonella, and Mobiluncus) were included for comparison. All Desulfovibrio species produced H2S and were desulfoviridin positive, and all Desulfovibrio species except D. piger were motile. The four Desulfovibrio species could be distinguished from each other using tests for catalase, indole, nitrate, urease, and growth on bile, with the following results (positive [+], negative [-], growth [G], and no growth [NG]): for D. piger, -, -, -, -, and G, respectively; for D. fairfieldensis, +, -, +, -, and G, respectively; for D. desulfuricans, -, -, +, +, and NG, respectively; and for D. vulgaris, -, +, -, -, and G, respectively. Resistance to the 10-microg colistin disk separated the Desulfovibrio species from most of the other genera, which were usually susceptible. These simple tests were useful for characterizing the Desulfovibrio species and differentiating them from other phenotypically similar genera.
Topics: Desulfovibrio; Humans; Microbial Sensitivity Tests; Phenotype
PubMed: 16081948
DOI: 10.1128/JCM.43.8.4041-4045.2005 -
ACS Chemical Biology Jul 2022Metal-dependent formate dehydrogenases are important enzymes due to their activity of CO reduction to formate. The tungsten-containing FdhAB formate dehydrogenase from...
Metal-dependent formate dehydrogenases are important enzymes due to their activity of CO reduction to formate. The tungsten-containing FdhAB formate dehydrogenase from Hildenborough is a good example displaying high activity, simple composition, and a notable structural and catalytic robustness. Here, we report the first spectroscopic redox characterization of FdhAB metal centers by EPR. Titration with dithionite or formate leads to reduction of three [4Fe-4S] clusters, and full reduction requires Ti(III)-citrate. The redox potentials of the four [4Fe-4S] centers range between -250 and -530 mV. Two distinct W signals were detected, W and W, which differ in only the -value. This difference can be explained by small variations in the twist angle of the two pyranopterins, as determined through DFT calculations of model compounds. The redox potential of W was determined to be -370 mV when reduced by dithionite and -340 mV when reduced by formate. The crystal structure of dithionite-reduced FdhAB was determined at high resolution (1.5 Å), revealing the same structural alterations as reported for the formate-reduced structure. These results corroborate a stable six-ligand W coordination in the catalytic intermediate W state of FdhAB.
Topics: Catalysis; Desulfovibrio; Desulfovibrio vulgaris; Dithionite; Electron Spin Resonance Spectroscopy; Formate Dehydrogenases; Formates; Metals; Oxidation-Reduction
PubMed: 35766974
DOI: 10.1021/acschembio.2c00336 -
Scientific Reports May 2020Sedimentary pyrite (FeS) is commonly thought to be a product of microbial sulfate reduction and hence may preserve biosignatures. However, proof that microorganisms are...
Sedimentary pyrite (FeS) is commonly thought to be a product of microbial sulfate reduction and hence may preserve biosignatures. However, proof that microorganisms are involved in pyrite formation is still lacking as only metastable iron sulfides are usually obtained in laboratory cultures. Here we show the rapid formation of large pyrite spherules through the sulfidation of Fe(III)-phosphate (FP) in the presence of a consortium of sulfur- and sulfate-reducing bacteria (SRB), Desulfovibrio and Sulfurospirillum, enriched from ferruginous and phosphate-rich Lake Pavin water. In biomineralization experiments inoculated with this consortium, pyrite formation occurred within only 3 weeks, likely enhanced by the local enrichment of polysulfides around SRB cells. During this same time frame, abiotic reaction of FP with sulfide led to the formation of vivianite (Fe(PO)·8HO) and mackinawite (FeS) only. Our results suggest that rates of pyritization vs. vivianite formation are regulated by SRB activity at the cellular scale, which enhances phosphate release into the aqueous phase by increased efficiency of iron sulfide precipitation, and thus that these microorganisms strongly influence biological productivity and Fe, S and P cycles in the environment.
Topics: Campylobacteraceae; Desulfovibrio; Iron; Lakes; Microbial Consortia; Oxidation-Reduction; Phosphates; Sulfates; Sulfides; Sulfur
PubMed: 32427954
DOI: 10.1038/s41598-020-64990-6