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[PMID]:28286022
[Au] Autor:Alonso BL; Irigoyen von Sierakowski A; Sáez Nieto JA; Rosel AB
[Ad] Endereço:Centro de salud de Vinaroz, c/ Arcipreste Bono 22, Vinaroz, Castellon, Spain. Electronic address: lopez_a2@hotmail.com.
[Ti] Título:First report of human infection by Christensenella minuta, a gram-negative, strickly anaerobic rod that inhabits the human intestine.
[So] Source:Anaerobe;44:124-125, 2017 Apr.
[Is] ISSN:1095-8274
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Christensenella minuta is a Gram-negative strictly anaerobic short rod that inhabits the human gut. This bacterium was isolated in a mixed infection with Desulfovibrio desulfuricansfrom the blood of a patient with a diagnosis of acute appendicitis. The strain was identified by 16S rRNA sequence analysis. As far as we know, this is the first time C.minuta has been isolated from a human clinical specimen.
[Mh] Termos MeSH primário: Apendicite/diagnóstico
Bacteriemia/diagnóstico
Clostridiales/isolamento & purificação
Coinfecção/diagnóstico
Infecções por Bactérias Gram-Positivas/diagnóstico
[Mh] Termos MeSH secundário: Adolescente
Apendicite/complicações
Apendicite/microbiologia
Bacteriemia/microbiologia
Bacteriemia/patologia
Clostridiales/classificação
Clostridiales/genética
Coinfecção/microbiologia
Coinfecção/patologia
DNA Bacteriano/química
DNA Bacteriano/genética
DNA Ribossômico/química
DNA Ribossômico/genética
Desulfovibrio desulfuricans/classificação
Desulfovibrio desulfuricans/genética
Desulfovibrio desulfuricans/isolamento & purificação
Infecções por Desulfovibrionaceae/diagnóstico
Infecções por Desulfovibrionaceae/microbiologia
Infecções por Desulfovibrionaceae/patologia
Infecções por Bactérias Gram-Positivas/microbiologia
Infecções por Bactérias Gram-Positivas/patologia
Seres Humanos
Masculino
RNA Ribossômico 16S/genética
Análise de Sequência de DNA
[Pt] Tipo de publicação:CASE REPORTS; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (DNA, Ribosomal); 0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170424
[Lr] Data última revisão:
170424
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170314
[St] Status:MEDLINE


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[PMID]:27993064
[Au] Autor:Liu YR; Lu X; Zhao L; An J; He JZ; Pierce EM; Johs A; Gu B
[Ad] Endereço:State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China.
[Ti] Título:Effects of Cellular Sorption on Mercury Bioavailability and Methylmercury Production by Desulfovibrio desulfuricans ND132.
[So] Source:Environ Sci Technol;50(24):13335-13341, 2016 Dec 20.
[Is] ISSN:1520-5851
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Microbial conversion of inorganic mercury (IHg) to methylmercury (MeHg) is a significant environmental concern because of the bioaccumulation and biomagnification of toxic MeHg in the food web. Laboratory incubation studies have shown that, despite the presence of large quantities of IHg in cell cultures, MeHg biosynthesis often reaches a plateau or a maximum within hours or a day by an as yet unexplained mechanism. Here we report that mercuric Hg(II) can be taken up rapidly by cells of Desulfovibrio desulfuricans ND132, but a large fraction of the Hg(II) is unavailable for methylation because of strong cellular sorption. Thiols, such as cysteine, glutathione, and penicillamine, added either simultaneously with Hg(II) or after cells have been exposed to Hg(II), effectively desorb or mobilize the bound Hg(II), leading to a substantial increase in MeHg production. The amount of thiol-desorbed Hg(II) is strongly correlated to the amount of MeHg produced (r = 0.98). However, cells do not preferentially take up Hg(II)-thiol complexes, but Hg(II)-ligand exchange between these complexes and the cell-associated proteins likely constrains Hg(II) uptake and methylation. We suggest that, aside from aqueous chemical speciation of Hg(II), binding and exchange of Hg(II) between cells and complexing ligands such as thiols and naturally dissolved organics in solution is an important controlling mechanism of Hg(II) bioavailability, which should be considered when predicting MeHg production in the environment.
[Mh] Termos MeSH primário: Desulfovibrio desulfuricans/metabolismo
Mercúrio/química
[Mh] Termos MeSH secundário: Disponibilidade Biológica
Compostos de Metilmercúrio/metabolismo
Compostos de Sulfidrila/metabolismo
Poluentes Químicos da Água/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Methylmercury Compounds); 0 (Sulfhydryl Compounds); 0 (Water Pollutants, Chemical); FXS1BY2PGL (Mercury)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170608
[Lr] Data última revisão:
170608
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161221
[St] Status:MEDLINE


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[PMID]:27671526
[Au] Autor:Cadby IT; Ibrahim SA; Faulkner M; Lee DJ; Browning D; Busby SJ; Lovering AL; Stapleton MR; Green J; Cole JA
[Ad] Endereço:Institute of Microbiology & Infection, School of Biosciences, University of Birmingham, Birmingham, B15 2TT, UK.
[Ti] Título:Regulation, sensory domains and roles of two Desulfovibrio desulfuricans ATCC27774 Crp family transcription factors, HcpR1 and HcpR2, in response to nitrosative stress.
[So] Source:Mol Microbiol;102(6):1120-1137, 2016 Dec.
[Is] ISSN:1365-2958
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In silico analyses identified a Crp/Fnr family transcription factor (HcpR) in sulfate-reducing bacteria that controls expression of the hcp gene, which encodes the hybrid cluster protein and contributes to nitrosative stress responses. There is only one hcpR gene in the model sulfate-reducing bacterium Desulfovibrio vulgaris Hildenborough, but two copies in Desulfovibrio desulfuricans 27774, which can use nitrate as an alternative electron acceptor to sulfate. Structures of the D. desulfuricans hcpR1, hcpR2 and hcp operons are reported. We present evidence that hcp expression is regulated by HcpR2, not by HcpR1, and that these two regulators differ in both their DNA-binding site specificity and their sensory domains. HcpR1 is predicted to be a b-type cytochrome. HcpR1 binds upstream of the hcpR1 operon and its synthesis is regulated coordinately with hcp in response to NO. In contrast, hcpR2 expression was not induced by nitrate, nitrite or NO. HcpR2 is an iron-sulfur protein that reacts with NO and O . We propose that HcpR1 and HcpR2 use different sensory mechanisms to regulate subsets of genes required for defense against NO-induced nitrosative stress, and that diversification of signal perception and DNA recognition by these two proteins is a product of D. desulfuricans adaptation to its particular environmental niche.
[Mh] Termos MeSH primário: Desulfovibrio desulfuricans/metabolismo
Nitratos/metabolismo
Fatores de Transcrição/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Bactérias/metabolismo
Biologia Computacional
Simulação por Computador
Desulfovibrio desulfuricans/genética
Proteínas com Ferro-Enxofre/metabolismo
Nitritos/metabolismo
Nitrosação/fisiologia
Óperon
Fatores de Transcrição/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Iron-Sulfur Proteins); 0 (Nitrates); 0 (Nitrites); 0 (Transcription Factors)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170811
[Lr] Data última revisão:
170811
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160928
[St] Status:MEDLINE
[do] DOI:10.1111/mmi.13540


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[PMID]:27502834
[Au] Autor:Courtney J; Deplanche K; Rees NV; Macaskie LE
[Ad] Endereço:School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK.
[Ti] Título:Biomanufacture of nano-Pd(0) by Escherichia coli and electrochemical activity of bio-Pd(0) made at the expense of H and formate as electron donors.
[So] Source:Biotechnol Lett;38(11):1903-1910, 2016 Nov.
[Is] ISSN:1573-6776
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: Palladised cells of Desulfovibrio desulfuricans and Shewanella oneidensis have been reported as fuel cell electrocatalysts but growth at scale may be unattractive/costly; we have evaluated the potential of using E. coli, using H /formate for Pd-nanoparticle manufacture. RESULTS: Using 'bio-Pd' made under H (20 wt%) cyclic voltammograms suggested electrochemical activity of bio-NPs in a native state, attributed to proton adsorption/desorption. Bio-Pd prepared using formate as the electron donor gave smaller, well separated NPs; this material showed no electrochemical properties, and hence little potential for fuel cell use using a simple preparation technique. Bio-Pd on S. oneidensis gave similar results to those obtained using E. coli. CONCLUSION: Bio-Pd is sufficiently conductive to make an E. coli-derived electrochemically active material on intact, unprocessed bacterial cells if prepared at the expense of H , showing potential for fuel cell applications using a simple one-step preparation method.
[Mh] Termos MeSH primário: Escherichia coli/crescimento & desenvolvimento
Formiatos/química
Hidrogênio/química
Paládio/química
[Mh] Termos MeSH secundário: Fontes de Energia Bioelétrica
Desulfovibrio desulfuricans/metabolismo
Eletroquímica
Elétrons
Escherichia coli/metabolismo
Formiatos/metabolismo
Hidrogênio/metabolismo
Nanoestruturas/química
Paládio/metabolismo
Shewanella/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Formates); 0YIW783RG1 (formic acid); 5TWQ1V240M (Palladium); 7YNJ3PO35Z (Hydrogen)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160810
[St] Status:MEDLINE


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[PMID]:27058913
[Au] Autor:Zhang M; Wang H; Han X
[Ad] Endereço:School of Resources and Environment, University of Jinan, Jinan 250022, China. Electronic address: stu_zhangml@ujn.edu.cn.
[Ti] Título:Preparation of metal-resistant immobilized sulfate reducing bacteria beads for acid mine drainage treatment.
[So] Source:Chemosphere;154:215-223, 2016 Jul.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Novel immobilized sulfate-reducing bacteria (SRB) beads were prepared for the treatment of synthetic acid mine drainage (AMD) containing high concentrations of Fe, Cu, Cd and Zn using up-flow anaerobic packed-bed bioreactor. The tolerance of immobilized SRB beads to heavy metals was significantly enhanced compared with that of suspended SRB. High removal efficiencies of sulfate (61-88%) and heavy metals (>99.9%) as well as slightly alkaline effluent pH (7.3-7.8) were achieved when the bioreactor was fed with acidic influent (pH 2.7) containing high concentrations of multiple metals (Fe 469 mg/L, Cu 88 mg/L, Cd 92 mg/L and Zn 128 mg/L), which showed that the bioreactor filled with immobilized SRB beads had tolerance to AMD containing high concentrations of heavy metals. Partially decomposed maize straw was a carbon source and stabilizing agent in the initial phase of bioreactor operation but later had to be supplemented by a soluble carbon source such as sodium lactate. The microbial community in the bioreactor was characterized by denaturing gradient gel electrophoresis (DGGE) and sequencing of partial 16S rDNA genes. Synergistic interaction between SRB (Desulfovibrio desulfuricans) and co-existing fermentative bacteria could be the key factor for the utilization of complex organic substrate (maize straw) as carbon and nutrients source for sulfate reduction.
[Mh] Termos MeSH primário: Bacteroides/metabolismo
Reatores Biológicos/microbiologia
Clostridiales/metabolismo
Desulfovibrio desulfuricans/metabolismo
Metais Pesados/química
Sulfatos/química
Águas Residuais/química
[Mh] Termos MeSH secundário: Ácidos/química
Carbono/química
Fermentação
Consórcios Microbianos
Mineração/métodos
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acids); 0 (Metals, Heavy); 0 (Sulfates); 0 (Waste Water); 7440-44-0 (Carbon)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:170801
[Lr] Data última revisão:
170801
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160409
[St] Status:MEDLINE


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[PMID]:26818576
[Au] Autor:Eaktasang N; Kang CS; Lim H; Kwean OS; Cho S; Kim Y; Kim HS
[Ad] Endereço:Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701 Republic of Korea.
[Ti] Título:Production of electrically-conductive nanoscale filaments by sulfate-reducing bacteria in the microbial fuel cell.
[So] Source:Bioresour Technol;210:61-7, 2016 Jun.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:This study reports that the obligate anaerobic microorganism, Desulfovibrio desulfuricans, a predominant sulfate-reducing bacterium (SRB) in soils and sediments, can produce nanoscale bacterial appendages for extracellular electron transfer. These nanofilaments were electrically-conductive (5.81S·m(-1)) and allowed SRBs to directly colonize the surface of insoluble or solid electron acceptors. Thus, the direct extracellular electron transfer to the insoluble electrode in the microbial fuel cell (MFC) was possible without inorganic electron-shuttling mediators. The production of nanofilaments was stimulated when only insoluble electron acceptors were available for cellular respiration. These results suggest that when availability of a soluble electron acceptor for SRBs (SO4(2-)) is limited, D. desulfuricans initiates the production of conductive nanofilaments as an alternative strategy to transfer electrons to insoluble electron acceptors. The findings of this study contribute to understanding of the role of SRBs in the biotransformation of various substances in soils and sediments and in the MFC.
[Mh] Termos MeSH primário: Fontes de Energia Bioelétrica/microbiologia
Desulfovibrio desulfuricans/metabolismo
Condutividade Elétrica
Nanopartículas/química
Sulfatos/metabolismo
[Mh] Termos MeSH secundário: Desulfovibrio desulfuricans/crescimento & desenvolvimento
Eletrodos
Elétrons
Microscopia de Força Atômica
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Sulfates)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160129
[St] Status:MEDLINE


  7 / 184 MEDLINE  
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[PMID]:26699472
[Au] Autor:Pagnier A; Martin L; Zeppieri L; Nicolet Y; Fontecilla-Camps JC
[Ad] Endereço:Metalloproteins Unit, Institut de Biologie Structurale Commissariat à l'Energie Atomique et aux Energies Renouvelables-Centre National de la Recherche Scientifique-Université Grenoble Alpes, 38044 Grenoble Cedex 9, France.
[Ti] Título:CO and CN- syntheses by [FeFe]-hydrogenase maturase HydG are catalytically differentiated events.
[So] Source:Proc Natl Acad Sci U S A;113(1):104-9, 2016 Jan 05.
[Is] ISSN:1091-6490
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The synthesis and assembly of the active site [FeFe] unit of [FeFe]-hydrogenases require at least three maturases. The radical S-adenosyl-l-methionine HydG, the best characterized of these proteins, is responsible for the synthesis of the hydrogenase CO and CN(-) ligands from tyrosine-derived dehydroglycine (DHG). We speculated that CN(-) and the CO precursor (-):CO2H may be generated through an elimination reaction. We tested this hypothesis with both wild type and HydG variants defective in second iron-sulfur cluster coordination by measuring the in vitro production of CO, CN(-), and (-):CO2H-derived formate. We indeed observed formate production under these conditions. We conclude that HydG is a multifunctional enzyme that produces DHG, CN(-), and CO at three well-differentiated catalytic sites. We also speculate that homocysteine, cysteine, or a related ligand could be involved in Fe(CO)x(CN)y transfer to the HydF carrier/scaffold.
[Mh] Termos MeSH primário: Monóxido de Carbono/síntese química
Cianetos/síntese química
Hidrogenase/química
Proteínas com Ferro-Enxofre/química
[Mh] Termos MeSH secundário: Catálise
Domínio Catalítico
Cisteína/química
Desulfovibrio desulfuricans/enzimologia
Homocisteína/química
Hidrogenase/genética
Proteínas com Ferro-Enxofre/genética
Ligantes
Estrutura Secundária de Proteína
S-Adenosilmetionina/química
Tirosina/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Cyanides); 0 (Iron-Sulfur Proteins); 0 (Ligands); 0LVT1QZ0BA (Homocysteine); 42HK56048U (Tyrosine); 7LP2MPO46S (S-Adenosylmethionine); 7U1EE4V452 (Carbon Monoxide); EC 1.12.- (iron hydrogenase); EC 1.12.7.2 (Hydrogenase); K848JZ4886 (Cysteine)
[Em] Mês de entrada:1605
[Cu] Atualização por classe:160705
[Lr] Data última revisão:
160705
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151225
[St] Status:MEDLINE
[do] DOI:10.1073/pnas.1515842113


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[PMID]:26722748
[Au] Autor:Slater JW; Shafaat HS
[Ad] Endereço:Department of Chemistry and Biochemistry and Ohio State Biochemistry Program, The Ohio State University , 100 W 18th Avenue, Columbus, Ohio 43210, United States.
[Ti] Título:Nickel-Substituted Rubredoxin as a Minimal Enzyme Model for Hydrogenase.
[So] Source:J Phys Chem Lett;6(18):3731-6, 2015 Sep 17.
[Is] ISSN:1948-7185
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A simple, functional mimic of [NiFe] hydrogenases based on a nickel-substituted rubredoxin (NiRd) protein is reported. NiRd is capable of light-initiated and solution-phase hydrogen production and demonstrates high electrocatalytic activity using protein film voltammetry. The catalytic voltammograms are modeled using analytical expressions developed for hydrogenase enzymes, revealing maximum turnover frequencies of approximately 20-100 s(-1) at 4 °C with an overpotential of 540 mV. These rates are directly comparable to those observed for [NiFe] hydrogenases under similar conditions. Like the native enzymes, the proton reduction activity of NiRd is strongly inhibited by carbon monoxide. This engineered rubredoxin-based enzyme is chemically and thermally robust, easily accessible, and highly tunable. These results have implications for understanding the enzymatic mechanisms of native hydrogenases, and, using NiRd as a scaffold, it will be possible to optimize this catalyst for application in sustainable fuel generation.
[Mh] Termos MeSH primário: Hidrogenase/metabolismo
Níquel/metabolismo
Rubredoxinas/metabolismo
[Mh] Termos MeSH secundário: Biocatálise
Monóxido de Carbono/farmacologia
Desulfovibrio desulfuricans/enzimologia
Desulfovibrio vulgaris/enzimologia
Hidrogenase/química
Modelos Moleculares
Níquel/química
Engenharia de Proteínas
Rubredoxinas/antagonistas & inibidores
Rubredoxinas/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Rubredoxins); 7OV03QG267 (Nickel); 7U1EE4V452 (Carbon Monoxide); EC 1.12.- (nickel-iron hydrogenase); EC 1.12.7.2 (Hydrogenase)
[Em] Mês de entrada:1609
[Cu] Atualização por classe:160102
[Lr] Data última revisão:
160102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160102
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jpclett.5b01750


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[PMID]:26509703
[Au] Autor:Cerqueira NM; Gonzalez PJ; Fernandes PA; Moura JJ; Ramos MJ
[Ad] Endereço:REQUIMTE/UCIBIO, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , Rua do Campo Alegre s/n, 4169-007 Porto, Portugal.
[Ti] Título:Periplasmic nitrate reductase and formate dehydrogenase: similar molecular architectures with very different enzymatic activities.
[So] Source:Acc Chem Res;48(11):2875-84, 2015 Nov 17.
[Is] ISSN:1520-4898
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:It is remarkable how nature has been able to construct enzymes that, despite sharing many similarities, have simple but key differences that tune them for completely different functions in living cells. Periplasmic nitrate reductase (Nap) and formate dehydrogenase (Fdh) from the DMSOr family are representative examples of this. Both enzymes share almost identical three-dimensional protein foldings and active sites, in terms of coordination number, geometry and nature of the ligands. The substrates of both enzymes (nitrate and formate) are polyatomic anions that also share similar charge and stereochemistry. In terms of the catalytic mechanism, both enzymes have a common activation mechanism (the sulfur-shift mechanism) that ensures a constant coordination number around the metal ion during the catalytic cycle. In spite of these similarities, they catalyze very different reactions: Nap abstracts an oxygen atom from nitrate releasing nitrite, whereas FdH catalyzes a hydrogen atom transfer from formate and releases carbon dioxide. In this Account, a critical analysis of structure, function, and catalytic mechanism of the molybdenum enzymes periplasmic nitrate reductase (Nap) and formate dehydrogenase (Fdh) is presented. We conclude that the main structural driving force that dictates the type of reaction, catalyzed by each enzyme, is a key difference on one active site residue that is located in the top region of the active sites of both enzymes. In both enzymes, the active site is centered on the metal ion of the cofactor (Mo in Nap and Mo or W in Fdh) that is coordinated by four sulfur atoms from two pyranopterin guanosine dinucleotide (PGD) molecules and by a sulfido. However, while in Nap there is a Cys directly coordinated to the Mo ion, in FdH there is a SeCys instead. In Fdh there is also an important His that interacts very closely with the SeCys, whereas in Nap the same position is occupied by a Met. The role of Cys in Nap and SeCys in FdH is similar in both enzymes; however, Met and His have different roles. His participates directly on catalysis, and it is therefore detrimental for the catalytic cycle of FdH. Met only participates in substrate binding. We concluded that this small but key difference dictates the type of reaction that is catalyzed by each enzyme. In addition, it allows explaining why formate can bind in the Nap active site in the same way as the natural substrate (nitrate), but the reaction becomes stalled afterward.
[Mh] Termos MeSH primário: Proteínas de Escherichia coli/química
Proteínas de Escherichia coli/ultraestrutura
Formiato Desidrogenases/química
Formiato Desidrogenases/ultraestrutura
Hidrogenase/química
Hidrogenase/ultraestrutura
Complexos Multienzimáticos/química
Complexos Multienzimáticos/ultraestrutura
Nitrato Redutase/química
Nitrato Redutase/ultraestrutura
[Mh] Termos MeSH secundário: Desulfovibrio desulfuricans
Modelos Químicos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Escherichia coli Proteins); 0 (Multienzyme Complexes); EC 1.12.7.2 (Hydrogenase); EC 1.2.1.2 (Formate Dehydrogenases); EC 1.2.1.2 (formate hydrogenlyase); EC 1.7.99.4 (Nitrate Reductase)
[Em] Mês de entrada:1605
[Cu] Atualização por classe:151120
[Lr] Data última revisão:
151120
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151029
[St] Status:MEDLINE
[do] DOI:10.1021/acs.accounts.5b00333


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[PMID]:26210529
[Au] Autor:Yue ZB; Li Q; Li CC; Chen TH; Wang J
[Ad] Endereço:School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui 230009, China.
[Ti] Título:Component analysis and heavy metal adsorption ability of extracellular polymeric substances (EPS) from sulfate reducing bacteria.
[So] Source:Bioresour Technol;194:399-402, 2015 Oct.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Extracellular polymeric substances (EPS) play an important role in the treatment of acid mine drainage (AMD) by sulfate-reducing bacteria (SRB). In this paper, Desulfovibrio desulfuricans was used as the test strain to explore the effect of heavy metals on the components and adsorption ability of EPS. Fourier-transform infrared (FTIR) spectroscopy analysis results showed that heavy metals did not influence the type of functional groups of EPS. Potentiometric titration results indicated that the acidic constants (pKa) of the EPS fell into three ranges of 3.5-4.0, 5.9-6.7, and 8.9-9.8. The adsorption site concentrations of the surface functional groups also increased. Adsorption results suggested that EPS had a specific binding affinity for the dosed heavy metal, and that EPS extracted from the Zn(2+)-dosed system had a higher binding affinity for all heavy metals. Additionally, Zn(2+) decreased the inhibitory effects of Cd(2+) and Cu(2+) on the SRB.
[Mh] Termos MeSH primário: Cádmio/química
Cobre/química
Desulfovibrio desulfuricans/metabolismo
Metais Pesados/química
Polímeros/química
Zinco/química
[Mh] Termos MeSH secundário: Ácidos
Adsorção
Carbono/química
Concentração de Íons de Hidrogênio
Fosfatos/química
Potenciometria
Espectroscopia de Infravermelho com Transformada de Fourier
Sulfatos/química
Propriedades de Superfície
Poluentes Químicos da Água/química
Purificação da Água
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Acids); 0 (Metals, Heavy); 0 (Phosphates); 0 (Polymers); 0 (Sulfates); 0 (Water Pollutants, Chemical); 00BH33GNGH (Cadmium); 7440-44-0 (Carbon); 789U1901C5 (Copper); J41CSQ7QDS (Zinc)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150727
[St] Status:MEDLINE



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