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[PMID]:28466260
[Au] Autor:Singh SB; Wilson M; Ritz N; Lin HC
[Ad] Endereço:Section of Gastroenterology, Medicine Service, New Mexico VA Health Care System, 1501 San Pedro SE, Albuquerque, NM, 87108, USA.
[Ti] Título:Autophagy Genes of Host Responds to Disruption of Gut Microbial Community by Antibiotics.
[So] Source:Dig Dis Sci;62(6):1486-1497, 2017 06.
[Is] ISSN:1573-2568
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Defective autophagic machinery, such as that in Crohn's disease patients homozygous for ATG16L1 risk allele, is associated with alteration of resident gut bacterial communities. However, whether or not host autophagy responds to changes in the resident gut microbial community is not known. Here, we investigated the effect of antibiotic-induced disruption of the gut microbiome (dysbiosis) on autophagy gene expression and the expression of antimicrobial peptides/protein (AMP) over time. AIM: To test the hypothesis that antibiotic treatment may cause time-dependent changes in gut bacterial density, autophagy genes, and antimicrobial protein/peptide gene expression. METHODS: Mice (n = 8 per group) were treated with antibiotic cocktail and sacrificed at different intervals of recovery (days 3, 7, 10, 14, 21, 28, 35, and 42) post-antibiotics. DNA and RNA were extracted from small intestinal tissues. Bacterial density, expression of host autophagy genes, and AMP genes were analyzed by relative quantitative PCR. Fold change difference in comparison with untreated control group was calculated using 2 method. Statistical analysis was performed using nonparametric Mann-Whitney test. RESULTS: Gut bacterial density changed in a time-dependent fashion in response to antibiotic treatment. These changes were concurrent with upregulation of autophagy genes and antimicrobial peptide/protein gene expression. We further showed that an oral gavage of a resident microbe Desulfovibrio, which bloomed in antibiotic-treated animals, induced Atg5 and lysozyme (Lyz) gene expression. CONCLUSION: Autophagy genes respond to dysbiosis induced by antibiotics. This response may be a host mechanism to detect and possibly correct dysbiosis by activating antimicrobial peptides/proteins that control the microbial load in the gut.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Peptídeos Catiônicos Antimicrobianos/genética
Autofagia/genética
Disbiose/microbiologia
Microbioma Gastrointestinal/efeitos dos fármacos
RNA Ribossômico 16S/análise
[Mh] Termos MeSH secundário: Animais
Proteína 5 Relacionada à Autofagia/genética
Proteínas Relacionadas à Autofagia/genética
Bacteroidetes
Células Cultivadas
Desulfovibrio
Desulfovibrio vulgaris
Disbiose/induzido quimicamente
Disbiose/genética
Células Epiteliais/efeitos dos fármacos
Feminino
Firmicutes
Expressão Gênica
Intestino Delgado/citologia
Intestino Delgado/microbiologia
Macrófagos/efeitos dos fármacos
Camundongos
Camundongos Endogâmicos C57BL
Muramidase/genética
Proteínas Associadas a Pancreatite
Proteínas/genética
Fatores de Tempo
Regulação para Cima
alfa-Defensinas/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Antimicrobial Cationic Peptides); 0 (Atg5 protein, mouse); 0 (Autophagy-Related Protein 5); 0 (Autophagy-Related Proteins); 0 (Pancreatitis-Associated Proteins); 0 (Proteins); 0 (RNA, Ribosomal, 16S); 0 (Reg3g protein, mouse); 0 (alpha-Defensins); 0 (cryptdin 4, mouse); EC 3.2.1.17 (Muramidase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171213
[Lr] Data última revisão:
171213
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1007/s10620-017-4589-8


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[PMID]:28874410
[Au] Autor:Zeng L; Wooton E; Stahl DA; Walian PJ
[Ad] Endereço:Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA.
[Ti] Título:Identification and Characterization of the Major Porin of Desulfovibrio vulgaris Hildenborough.
[So] Source:J Bacteriol;199(23), 2017 Dec 01.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Due in large part to their ability to facilitate the diffusion of a diverse range of solutes across the outer membrane (OM) of Gram-negative bacteria, the porins represent one of the most prominent and important bacterial membrane protein superfamilies. Notably, for the Gram-negative bacterium Hildenborough, a model organism for studies of sulfate-reducing bacteria, no genes for porins have been identified or proposed in its annotated genome. Results from initial biochemical studies suggested that the product of the DVU0799 gene, which is one of the most abundant proteins of the Hildenborough OM and purified as a homotrimeric complex, was a strong porin candidate. To investigate this possibility, this protein was further characterized biochemically and biophysically. Structural analyses via electron microscopy of negatively stained protein identified trimeric particles with stain-filled depressions and structural modeling suggested a ß-barrel structure for the monomer, motifs common among the known porins. Functional studies were performed in which crude OM preparations or purified DVU0799 was reconstituted into proteoliposomes and the proteoliposomes were examined for permeability against a series of test solutes. The results obtained establish DVU0799 to be a pore-forming protein with permeability properties similar to those observed for classical bacterial porins, such as those of Taken together, these findings identify this highly abundant OM protein to be the major porin of Hildenborough. Classification of DVU0799 in this model organism expands the database of functionally characterized porins and may also extend the range over which sequence analysis strategies can be used to identify porins in other bacterial genomes. Porins are membrane proteins that form transmembrane pores for the passive transport of small molecules across the outer membranes of Gram-negative bacteria. The present study identified and characterized the major porin of the model sulfate-reducing bacterium Hildenborough, observing its preference for anionic sugars over neutral ones. Its predicted architecture appears to be novel for a classical porin, as its core ß-barrel structure is of a type typically found in solute-specific channels. Broader use of the methods employed here, such as assays for channel permeability and electron microscopy of purified samples, is expected to help expand the database of confirmed porin sequences and improve the range over which sequence analysis-based strategies can be used to identify porins in other Gram-negative bacteria. Functional characterization of these critical gatekeeping proteins from divergent species should offer an improved understanding of the physiological features that determine their habitat range and supporting activities.
[Mh] Termos MeSH primário: Proteínas da Membrana Bacteriana Externa/metabolismo
Proteínas de Bactérias/metabolismo
Desulfovibrio vulgaris/metabolismo
Porinas/metabolismo
[Mh] Termos MeSH secundário: Transporte Biológico/fisiologia
Escherichia coli/metabolismo
Proteolipídeos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Bacterial Proteins); 0 (Porins); 0 (Proteolipids); 0 (proteoliposomes)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171119
[Lr] Data última revisão:
171119
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170907
[St] Status:MEDLINE


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[PMID]:28615449
[Au] Autor:Hoben JP; Lubner CE; Ratzloff MW; Schut GJ; Nguyen DMN; Hempel KW; Adams MWW; King PW; Miller AF
[Ad] Endereço:From the Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506.
[Ti] Título:Equilibrium and ultrafast kinetic studies manipulating electron transfer: A short-lived flavin semiquinone is not sufficient for electron bifurcation.
[So] Source:J Biol Chem;292(34):14039-14049, 2017 Aug 25.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Flavin-based electron transfer bifurcation is emerging as a fundamental and powerful mechanism for conservation and deployment of electrochemical energy in enzymatic systems. In this process, a pair of electrons is acquired at intermediate reduction potential ( intermediate reducing power), and each electron is passed to a different acceptor, one with lower and the other with higher reducing power, leading to "bifurcation." It is believed that a strongly reducing semiquinone species is essential for this process, and it is expected that this species should be kinetically short-lived. We now demonstrate that the presence of a short-lived anionic flavin semiquinone (ASQ) is not sufficient to infer the existence of bifurcating activity, although such a species may be necessary for the process. We have used transient absorption spectroscopy to compare the rates and mechanisms of decay of ASQ generated photochemically in bifurcating NADH-dependent ferredoxin-NADP oxidoreductase and the non-bifurcating flavoproteins nitroreductase, NADH oxidase, and flavodoxin. We found that different mechanisms dominate ASQ decay in the different protein environments, producing lifetimes ranging over 2 orders of magnitude. Capacity for electron transfer among redox cofactors charge recombination with nearby donors can explain the range of ASQ lifetimes that we observe. Our results support a model wherein efficient electron propagation can explain the short lifetime of the ASQ of bifurcating NADH-dependent ferredoxin-NADP oxidoreductase I and can be an indication of capacity for electron bifurcation.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Flavina-Adenina Dinucleotídeo/análogos & derivados
Flavodoxina/metabolismo
Modelos Moleculares
Complexos Multienzimáticos/metabolismo
NADH NADPH Oxirredutases/metabolismo
Nitrorredutases/metabolismo
Oxirredutases/metabolismo
[Mh] Termos MeSH secundário: Apoenzimas/química
Apoenzimas/genética
Apoenzimas/metabolismo
Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Ácido Benzoico/química
Ácido Benzoico/metabolismo
Biocatálise
Desulfovibrio vulgaris/enzimologia
Transporte de Elétrons
Enterobacter cloacae/enzimologia
Flavina-Adenina Dinucleotídeo/química
Flavina-Adenina Dinucleotídeo/metabolismo
Flavodoxina/química
Flavodoxina/genética
Holoenzimas/química
Holoenzimas/genética
Holoenzimas/metabolismo
Complexos Multienzimáticos/química
Complexos Multienzimáticos/genética
NADH NADPH Oxirredutases/química
NADH NADPH Oxirredutases/genética
Nitrorredutases/química
Nitrorredutases/genética
Oxirredução
Oxirredutases/química
Oxirredutases/genética
Pyrococcus furiosus/enzimologia
Proteínas Recombinantes de Fusão/química
Proteínas Recombinantes de Fusão/metabolismo
Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
Mutação Silenciosa
Thermus thermophilus/enzimologia
ortoaminobenzoatos/química
ortoaminobenzoatos/metabolismo
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Apoenzymes); 0 (Bacterial Proteins); 0 (Flavodoxin); 0 (Holoenzymes); 0 (Multienzyme Complexes); 0 (Recombinant Fusion Proteins); 0 (Recombinant Proteins); 0 (ortho-Aminobenzoates); 0YS975XI6W (anthranilic acid); 146-14-5 (Flavin-Adenine Dinucleotide); 35919-91-6 (flavin semiquinone); 8SKN0B0MIM (Benzoic Acid); 952VN06WBB (fenamic acid); EC 1.- (Oxidoreductases); EC 1.18.1.3 (ferredoxin-NAD+ reductase); EC 1.6.- (NADH oxidase); EC 1.6.- (NADH, NADPH Oxidoreductases); EC 1.7.- (Nitroreductases)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170912
[Lr] Data última revisão:
170912
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170616
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.794214


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[PMID]:28436827
[Au] Autor:Zhou C; Zhou Y; Rittmann BE
[Ad] Endereço:Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, USA. Electronic address: zhou_SCEB@asu.edu.
[Ti] Título:Reductive precipitation of sulfate and soluble Fe(III) by Desulfovibrio vulgaris: Electron donor regulates intracellular electron flow and nano-FeS crystallization.
[So] Source:Water Res;119:91-101, 2017 Aug 01.
[Is] ISSN:1879-2448
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Fully understanding the metabolism of SRB provides fundamental guidelines for allowing the microorganisms to provide more beneficial services in water treatment and resource recovery. The electron-transfer pathway of sulfate respiration by Desulfovibrio vulgaris is well studied, but still partly unresolved. Here we provide deeper insight by comprehensively monitoring metabolite changes during D. vulgaris metabolism with two electron donors, lactate and pyruvate, in presence or absence of citrate-chelated soluble Fe as an additional competing electron acceptor. H was produced from lactate oxidation to pyruvate, but pyruvate oxidation produced mostly formate. Accumulation of lactate-originated H during lag phases inhibited pyruvate transformation to acetate. Sulfate reduction was initiated by lactate-originated H , but MQ-mediated e flow initiated sulfate reduction without delay when pyruvate was the donor. When H -induced electron flow gave priority to Fe reduction over sulfate reduction, the long lag phase before sulfate reduction shortened the time for iron-sulfide crystallite growth and led to smaller mackinawite (Fe S) nanocrystallites. Synthesizing all the results, we propose that electron flow from lactate or pyruvate towards SO reduction to H S are through at least three routes that are regulated by the e donor (lactate or pyruvate) and the presence or absence of another e acceptor (Fe here). These routes are not competing, but complementary: e.g., H or formate production and oxidation were necessary for sulfite and disulfide/trisulfide reduction to sulfide. Our study suggests that the e donor provides a practical tool to regulate and optimize SRB-predominant bioremediation systems.
[Mh] Termos MeSH primário: Desulfovibrio vulgaris
Compostos Férricos/química
Sulfatos/química
[Mh] Termos MeSH secundário: Cristalização
Desulfovibrio
Elétrons
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ferric Compounds); 0 (Sulfates)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170425
[St] Status:MEDLINE


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[PMID]:28320772
[Au] Autor:Turkarslan S; Raman AV; Thompson AW; Arens CE; Gillespie MA; von Netzer F; Hillesland KL; Stolyar S; López García de Lomana A; Reiss DJ; Gorman-Lewis D; Zane GM; Ranish JA; Wall JD; Stahl DA; Baliga NS
[Ad] Endereço:Institute for Systems Biology, Seattle, WA, USA.
[Ti] Título:Mechanism for microbial population collapse in a fluctuating resource environment.
[So] Source:Mol Syst Biol;13(3):919, 2017 Mar 20.
[Is] ISSN:1744-4292
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Managing trade-offs through gene regulation is believed to confer resilience to a microbial community in a fluctuating resource environment. To investigate this hypothesis, we imposed a fluctuating environment that required the sulfate-reducer to undergo repeated ecologically relevant shifts between retaining metabolic independence (active capacity for sulfate respiration) and becoming metabolically specialized to a mutualistic association with the hydrogen-consuming Strikingly, the microbial community became progressively less proficient at restoring the environmentally relevant physiological state after each perturbation and most cultures collapsed within 3-7 shifts. Counterintuitively, the collapse phenomenon was prevented by a single regulatory mutation. We have characterized the mechanism for collapse by conducting RNA-seq analysis, proteomics, microcalorimetry, and single-cell transcriptome analysis. We demonstrate that the collapse was caused by conditional gene regulation, which drove precipitous decline in intracellular abundance of essential transcripts and proteins, imposing greater energetic burden of regulation to restore function in a fluctuating environment.
[Mh] Termos MeSH primário: Desulfovibrio vulgaris/crescimento & desenvolvimento
Mathanococcus/crescimento & desenvolvimento
Biologia de Sistemas/métodos
[Mh] Termos MeSH secundário: Desulfovibrio vulgaris/genética
Evolução Molecular Direcionada
Perfilação da Expressão Gênica
Mathanococcus/genética
Oxirredução
Fenótipo
Proteômica
Análise de Sequência de RNA
Análise de Célula Única
Sulfatos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Sulfates)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170731
[Lr] Data última revisão:
170731
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170322
[St] Status:MEDLINE
[do] DOI:10.15252/msb.20167058


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[PMID]:28319099
[Au] Autor:Marques MC; Tapia C; Gutiérrez-Sanz O; Ramos AR; Keller KL; Wall JD; De Lacey AL; Matias PM; Pereira IAC
[Ad] Endereço:Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal.
[Ti] Título:The direct role of selenocysteine in [NiFeSe] hydrogenase maturation and catalysis.
[So] Source:Nat Chem Biol;13(5):544-550, 2017 May.
[Is] ISSN:1552-4469
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Hydrogenases are highly active enzymes for hydrogen production and oxidation. [NiFeSe] hydrogenases, in which selenocysteine is a ligand to the active site Ni, have high catalytic activity and a bias for H production. In contrast to [NiFe] hydrogenases, they display reduced H inhibition and are rapidly reactivated after contact with oxygen. Here we report an expression system for production of recombinant [NiFeSe] hydrogenase from Desulfovibrio vulgaris Hildenborough and study of a selenocysteine-to-cysteine variant (Sec489Cys) in which, for the first time, a [NiFeSe] hydrogenase was converted to a [NiFe] type. This modification led to severely reduced Ni incorporation, revealing the direct involvement of this residue in the maturation process. The Ni-depleted protein could be partly reconstituted to generate an enzyme showing much lower activity and inactive states characteristic of [NiFe] hydrogenases. The Ni-Sec489Cys variant shows that selenium has a crucial role in protection against oxidative damage and the high catalytic activities of the [NiFeSe] hydrogenases.
[Mh] Termos MeSH primário: Biocatálise
Desulfovibrio vulgaris/enzimologia
Hidrogenase/química
Hidrogenase/metabolismo
Selenocisteína/metabolismo
[Mh] Termos MeSH secundário: Desulfovibrio vulgaris/metabolismo
Ligantes
Modelos Moleculares
Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
Selenocisteína/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ligands); 0 (Recombinant Proteins); 0CH9049VIS (Selenocysteine); EC 1.12.- (nickel-iron-selenium hydrogenase); EC 1.12.7.2 (Hydrogenase)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170425
[Lr] Data última revisão:
170425
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170321
[St] Status:MEDLINE
[do] DOI:10.1038/nchembio.2335


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[PMID]:28192203
[Au] Autor:Sugimoto Y; Kitazumi Y; Shirai O; Nishikawa K; Higuchi Y; Yamamoto M; Kano K
[Ad] Endereço:Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
[Ti] Título:Electrostatic roles in electron transfer from [NiFe] hydrogenase to cytochrome c from Desulfovibrio vulgaris Miyazaki F.
[So] Source:Biochim Biophys Acta;1865(5):481-487, 2017 05.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Electrostatic interactions between proteins are key factors that govern the association and reaction rate. We spectroscopically determine the second-order reaction rate constant (k) of electron transfer from [NiFe] hydrogenase (H ase) to cytochrome (cyt) c at various ionic strengths (I). The k value decreases with I. To analyze the results, we develop a semi-analytical formula for I dependence of k based on the assumptions that molecules are spherical and the reaction proceeds via a transition state. Fitting of the formula to the experimental data reveals that the interaction occurs in limited regions with opposite charges and with radii much smaller than those estimated from crystal structures. This suggests that local charges in H ase and cyt c play important roles in the reaction. Although the crystallographic data indicate a positive electrostatic potential over almost the entire surface of the proteins, there exists a small region with negative potential on H ase at which the electron transfer from H ase to cyt c may occur. This local negative potential region is identical to the hypothetical interaction sphere predicted by the analysis. Furthermore, I dependence of k is predicted by the Adaptive Poisson-Boltzmann Solver considering all charges of the amino acids in the proteins and the configuration of H ase/cyt c complex. The calculation reproduces the experimental results except at extremely low I. These results indicate that the stabilization derived from the local electrostatic interaction in the H ase/cyt c complex overcomes the destabilization derived from the electrostatic repulsion of the overall positive charge of both proteins.
[Mh] Termos MeSH primário: Grupo dos Citocromos c/química
Desulfovibrio vulgaris/enzimologia
Hidrogenase/química
Modelos Moleculares
Conformação Proteica
[Mh] Termos MeSH secundário: Respiração Celular
Grupo dos Citocromos c/metabolismo
Transporte de Elétrons
Elétrons
Hidrogenase/metabolismo
Cinética
Concentração Osmolar
Oxirredução
Mapas de Interação de Proteínas
Eletricidade Estática
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Cytochrome c Group); 9035-44-3 (cytochrome c(3)); EC 1.12.- (nickel-iron hydrogenase); EC 1.12.7.2 (Hydrogenase)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170718
[Lr] Data última revisão:
170718
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170214
[St] Status:MEDLINE


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[PMID]:27852449
[Au] Autor:Liu J; Zhou L; Dong F; Hudson-Edwards KA
[Ad] Endereço:The Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, Southwest University of Science and Technology, Mianyang, 621010, China.
[Ti] Título:Enhancing As(V) adsorption and passivation using biologically formed nano-sized FeS coatings on limestone: Implications for acid mine drainage treatment and neutralization.
[So] Source:Chemosphere;168:529-538, 2017 Feb.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The iron-reducing bacterium Acidiphilium cryputum JF-5 and a sulfate reducing bacterium (SRB) collected and purified from the mine drainage of a copper mine in the northwest of Sichuan Province, China, were used to biologically synthesize nano-sized FeS-coated limestone to remove As(V) from solution. The adsorption efficiency of As(V) is improved from 6.64 µg/g with limestone alone to 187 µg/g with the FeS coated limestone in both batch and column experiments. The hydraulic conductivity of the columns are also improved by the presence of the nano-sized FeS coatings, but the solution neutralization performance of the limestone can be reduced by passivation by gypsum and Fe(III) precipitates. Calculations for FeS-coated limestone dissolution experiments show that the process can be described as n = At - n . The results suggest that FeS-coated limestone may be an effective medium for remediating As(V)-bearing solutions such as acid mine drainage in systems such as Permeable Reactive Barriers.
[Mh] Termos MeSH primário: Arsenicais/isolamento & purificação
Carbonato de Cálcio/química
Compostos Ferrosos/química
Mineração
Nanopartículas/química
Poluentes Químicos da Água/isolamento & purificação
Purificação da Água/métodos
[Mh] Termos MeSH secundário: Acidiphilium/crescimento & desenvolvimento
Adsorção
Biodegradação Ambiental
China
Desulfovibrio vulgaris/crescimento & desenvolvimento
Água Subterrânea/química
Água Subterrânea/microbiologia
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Arsenicals); 0 (Ferrous Compounds); 0 (Water Pollutants, Chemical); H0G9379FGK (Calcium Carbonate); TH5J4TUX6S (ferrous sulfide)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170119
[Lr] Data última revisão:
170119
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161118
[St] Status:MEDLINE


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[PMID]:27486032
[Au] Autor:Lobo SA; Videira MA; Pacheco I; Wass MN; Warren MJ; Teixeira M; Matias PM; Romão CV; Saraiva LM
[Ad] Endereço:Instituto de Tecnologia Química e Biológica NOVA, Avenida da República (EAN), Oeiras, 2780-157, Portugal.
[Ti] Título:Desulfovibrio vulgaris CbiK cobaltochelatase: evolution of a haem binding protein orchestrated by the incorporation of two histidine residues.
[So] Source:Environ Microbiol;19(1):106-118, 2017 Jan.
[Is] ISSN:1462-2920
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The sulfate-reducing bacteria of the Desulfovibrio genus make three distinct modified tetrapyrroles, haem, sirohaem and adenosylcobamide, where sirohydrochlorin acts as the last common biosynthetic intermediate along the branched tetrapyrrole pathway. Intriguingly, D. vulgaris encodes two sirohydrochlorin chelatases, CbiK and CbiK , that insert cobalt/iron into the tetrapyrrole macrocycle but are thought to be distinctly located in the periplasm and cytoplasm respectively. Fusing GFP onto the C-terminus of CbiK confirmed that the protein is transported to the periplasm. The structure-function relationship of CbiK was studied by constructing eleven site-directed mutants and determining their chelatase activities, oligomeric status and haem binding abilities. Residues His154 and His216 were identified as essential for metal-chelation of sirohydrochlorin. The tetrameric form of the protein is stabilized by Arg54 and Glu76, which form hydrogen bonds between two subunits. His96 is responsible for the binding of two haem groups within the main central cavity of the tetramer. Unexpectedly, CbiK is shown to bind two additional haem groups through interaction with His103. Thus, although still retaining cobaltochelatase activity, the presence of His96 and His103 in CbiK , which are absent from all other known bacterial cobaltochelatases, has evolved CbiK a new function as a haem binding protein permitting it to act as a potential haem chaperone or transporter.
[Mh] Termos MeSH primário: Proteínas de Bactérias/genética
Desulfovibrio vulgaris/enzimologia
Desulfovibrio vulgaris/genética
Heme/análogos & derivados
Liases/genética
Tetrapirróis/metabolismo
Uroporfirinas/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Transporte/genética
Desulfovibrio vulgaris/metabolismo
Ferroquelatase/genética
Ferroquelatase/metabolismo
Heme/metabolismo
Hemeproteínas/genética
Histidina/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Carrier Proteins); 0 (Hemeproteins); 0 (Tetrapyrroles); 0 (Uroporphyrins); 0 (heme-binding protein); 42VZT0U6YR (Heme); 4QD397987E (Histidine); 52553-42-1 (siroheme); 65207-12-7 (sirohydrochlorin); EC 4.- (Lyases); EC 4.99.1.- (cobaltochelatase); EC 4.99.1.1 (Ferrochelatase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170908
[Lr] Data última revisão:
170908
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160804
[St] Status:MEDLINE
[do] DOI:10.1111/1462-2920.13479


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[PMID]:27686721
[Au] Autor:Barca C; Ranava D; Bauzan M; Ferrasse JH; Giudici-Orticoni MT; Soric A
[Ad] Endereço:Aix Marseille Univ, CNRS, Centrale Marseille, M2P2, Marseille, France.
[Ti] Título:Fermentative hydrogen production in an up-flow anaerobic biofilm reactor inoculated with a co-culture of Clostridium acetobutylicum and Desulfovibrio vulgaris.
[So] Source:Bioresour Technol;221:526-533, 2016 Dec.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Dark fermentation systems often show low H yields and unstable H production, as the result of the variability of microbial dynamics and metabolic pathways. Recent batch investigations have demonstrated that an artificial consortium of two anaerobic bacteria, Clostridium acetobutylicum and Desulfovibrio vulgaris Hildenborough, may redirect metabolic fluxes and improve H yields. This study aimed at evaluating the scale-up from batch to continuous H production in an up-flow anaerobic packed-bed reactor (APBR) continuously fed with a glucose-medium. The effects of various parameters, including void hydraulic retention time (HRTv), pH, and alkalinity, on H production performances and metabolic pathways were investigated. The results demonstrated that a stable H production was reached after 3-4days of operation. H production rates increased significantly with decreasing HRTv from 4 to 2h. Instead, H yields remained almost stable despite the change in HRTv, indicating that the decrease in HRTv did not affect the global metabolism.
[Mh] Termos MeSH primário: Biofilmes
Reatores Biológicos/microbiologia
Clostridium acetobutylicum/metabolismo
Desulfovibrio vulgaris/metabolismo
Hidrogênio/metabolismo
[Mh] Termos MeSH secundário: Anaerobiose
Bactérias Anaeróbias/metabolismo
Técnicas de Cocultura
Fermentação
Glucose/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
7YNJ3PO35Z (Hydrogen); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170923
[Lr] Data última revisão:
170923
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161001
[St] Status:MEDLINE



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