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  1 / 1231 MEDLINE  
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[PMID]:29040307
[Au] Autor:Zhang K; Chen XL; Guo WC; Luo HJ; Gong ZJ; Li BW; Wu WF
[Ad] Endereço:School of Energy & Environment, Inner Mongolia University of Science & Technology, Baotou, Inner Mongolia Autonomous Region, China.
[Ti] Título:Effects of biomass reducing agent on magnetic properties and phase transformation of Baotou low-grade limonite during magnetizing-roasting.
[So] Source:PLoS One;12(10):e0186274, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Biomass was used as reducing agent to roast the Baotou low-grade limonite in a high temperature vacuum atmosphere furnace. The effect of calcination temperature, time and ratio of reducing agent on the magnetic properties of calcined ore was studied by VSM. The phase and microstructure changes of limonite before and after calcination were analyzed by XRD and SEM. The results show that in the roasting process the phase transition process of the ferrous material in limonite is first dehydrated at high temperature to formα-Fe2O3, and then it is converted into Fe3O4 by the reduction of biomass. With the increase of calcination temperature, the magnetic properties of the calcined ore first increase and then decrease. When the temperature is higher than 650°C, Fe3O4 will become Fe2SiO4, resulting in reduced the magnetic material in calcined ore and the magnetic weakened. The best magnetization effect was obtained when the roasting temperature is 550°C, the percentage of biomass was 15% and the roasting time was 30min. The saturation magnetization can reach 60.13emu·g-1, the recovery of iron was 72% and the grade of iron was 58%.
[Mh] Termos MeSH primário: Biomassa
Compostos Férricos/química
Magnetismo
Substâncias Redutoras/química
[Mh] Termos MeSH secundário: Temperatura Alta
Ferro/química
Microscopia Eletrônica de Varredura/métodos
Difração de Raios X/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ferric Compounds); 0 (Reducing Agents); 2UA751211N (ferric hydroxide); E1UOL152H7 (Iron)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171018
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0186274


  2 / 1231 MEDLINE  
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[PMID]:28902505
[Au] Autor:Matoba Y; Kihara S; Muraki Y; Bando N; Yoshitsu H; Kuroda T; Sakaguchi M; Kayama K; Tai H; Hirota S; Ogura T; Sugiyama M
[Ad] Endereço:Graduate School of Biomedical & Health Sciences, Hiroshima University , Kasumi 1-2-3, Minami-ku, Hiroshima 734-8551, Japan.
[Ti] Título:Activation Mechanism of the Streptomyces Tyrosinase Assisted by the Caddie Protein.
[So] Source:Biochemistry;56(41):5593-5603, 2017 Oct 17.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Tyrosinase (EC 1.14.18.1), which possesses two copper ions at the active center, catalyzes a rate-limiting reaction of melanogenesis, that is, the conversion of a phenol to the corresponding ortho-quinone. The enzyme from the genus Streptomyces is generated as a complex with a "caddie" protein that assists the transport of two copper ions into the active center. In this complex, the Tyr residue in the caddie protein was found to be accommodated in the pocket of the active center of tyrosinase, probably in a manner similar to that of l-tyrosine as a genuine substrate of tyrosinase. Under physiological conditions, the addition of the copper ion to the complex releases tyrosinase from the complex, in accordance with the aggregation of the caddie protein. The release of the copper-bound tyrosinase was found to be accelerated by adding reducing agents under aerobic conditions. Mass spectroscopic analysis indicated that the Tyr residue was converted to a reactive quinone, and resonance Raman spectroscopic analysis indicated that the conversion occurred through the formations of µ-η :η -peroxo-dicopper(II) and Cu(II)-semiquinone. Electron paramagnetic resonance analysis under anaerobic conditions and Fourier transform infrared spectroscopic analysis using CO as a structural probe under anaerobic conditions indicated that the copper transportation process to the active center is a reversible event in the tyrosinase/caddie complex. Aggregation of the caddie protein, which is triggered by the conversion of the Tyr residue to dopaquinone, may ensure the generation of fully activated tyrosinase.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Proteínas de Transporte/metabolismo
Cobre/metabolismo
Modelos Moleculares
Monofenol Mono-Oxigenase/metabolismo
Streptomyces/enzimologia
[Mh] Termos MeSH secundário: Substituição de Aminoácidos
Apoenzimas/química
Apoenzimas/genética
Apoenzimas/metabolismo
Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Benzoquinonas/química
Benzoquinonas/metabolismo
Sítios de Ligação
Proteínas de Transporte/química
Proteínas de Transporte/genética
Domínio Catalítico
Cobre/química
Di-Hidroxifenilalanina/análogos & derivados
Di-Hidroxifenilalanina/química
Di-Hidroxifenilalanina/metabolismo
Ativação Enzimática/efeitos dos fármacos
Monofenol Mono-Oxigenase/química
Monofenol Mono-Oxigenase/genética
Mutação
Oxirredução
Agregados Proteicos/efeitos dos fármacos
Multimerização Proteica/efeitos dos fármacos
Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
Substâncias Redutoras/química
Solubilidade
Tirosina/química
Tirosina/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Apoenzymes); 0 (Bacterial Proteins); 0 (Benzoquinones); 0 (Carrier Proteins); 0 (Protein Aggregates); 0 (Recombinant Proteins); 0 (Reducing Agents); 42HK56048U (Tyrosine); 63-84-3 (Dihydroxyphenylalanine); 789U1901C5 (Copper); 8F09Y50AX6 (dopaquinone); EC 1.14.18.1 (Monophenol Monooxygenase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170914
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00635


  3 / 1231 MEDLINE  
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[PMID]:28805389
[Au] Autor:Jiang S; Penner MH
[Ad] Endereço:Department of Food Science and Technology, Oregon State University , Corvallis, Oregon 97331-6602, United States.
[Ti] Título:Overcoming Reductant Interference in Peroxidase-Based Assays for Hydrogen Peroxide Quantification.
[So] Source:J Agric Food Chem;65(37):8213-8219, 2017 Sep 20.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A problem commonly encountered when using peroxidase-based methods for hydrogen peroxide quantification in biobased matrixes is interference due to the presence of endogenous reductants. Such assays are typically based on the generation of an oxidized reporter molecule in direct proportion to the amount of hydrogen peroxide reduced in the peroxidase-catalyzed reaction. Endogenous reductants confound such assays by reducing the oxidized reporter molecule, thus resulting in underestimates of hydrogen peroxide content. In the present work, we demonstrate how this problem can be circumvented by selectively oxidizing offending compounds by treatment with the oxidized reporter molecule prior to initiating the peroxidase reaction for hydrogen peroxide quantification. The approach is demonstrated using horseradish peroxidase, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), as the reporter molecule and a representative garlic paste as the hydrogen peroxide-containing biobased matrix. The approach is expected to be generally applicable to a wide range of peroxidase-based assays when applied to complex biobased systems.
[Mh] Termos MeSH primário: Peróxido de Hidrogênio/química
Peroxidase/química
Substâncias Redutoras/química
[Mh] Termos MeSH secundário: Catálise
Alho/química
Cinética
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Reducing Agents); BBX060AN9V (Hydrogen Peroxide); EC 1.11.1.7 (Peroxidase)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170815
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b02248


  4 / 1231 MEDLINE  
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[PMID]:28784660
[Au] Autor:Pence N; Tokmina-Lukaszewska M; Yang ZY; Ledbetter RN; Seefeldt LC; Bothner B; Peters JW
[Ad] Endereço:From the Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164.
[Ti] Título:Unraveling the interactions of the physiological reductant flavodoxin with the different conformations of the Fe protein in the nitrogenase cycle.
[So] Source:J Biol Chem;292(38):15661-15669, 2017 Sep 22.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Nitrogenase reduces dinitrogen (N ) to ammonia in biological nitrogen fixation. The nitrogenase Fe protein cycle involves a transient association between the reduced, MgATP-bound Fe protein and the MoFe protein and includes electron transfer, ATP hydrolysis, release of P , and dissociation of the oxidized, MgADP-bound Fe protein from the MoFe protein. The cycle is completed by reduction of oxidized Fe protein and nucleotide exchange. Recently, a kinetic study of the nitrogenase Fe protein cycle involving the physiological reductant flavodoxin reported a major revision of the rate-limiting step from MoFe protein and Fe protein dissociation to release of P Because the Fe protein cannot interact with flavodoxin and the MoFe protein simultaneously, knowledge of the interactions between flavodoxin and the different nucleotide states of the Fe protein is critically important for understanding the Fe protein cycle. Here we used time-resolved limited proteolysis and chemical cross-linking to examine nucleotide-induced structural changes in the Fe protein and their effects on interactions with flavodoxin. Differences in proteolytic cleavage patterns and chemical cross-linking patterns were consistent with known nucleotide-induced structural differences in the Fe protein and indicated that MgATP-bound Fe protein resembles the structure of the Fe protein in the stabilized nitrogenase complex structures. Docking models and cross-linking patterns between the Fe protein and flavodoxin revealed that the MgADP-bound state of the Fe protein has the most complementary docking interface with flavodoxin compared with the MgATP-bound state. Together, these findings provide new insights into the control mechanisms in protein-protein interactions during the Fe protein cycle.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Proteínas de Bactérias/metabolismo
Flavodoxina/metabolismo
Ferro/metabolismo
Nitrogenase/metabolismo
Substâncias Redutoras/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Azotobacter vinelandii/enzimologia
Simulação de Acoplamento Molecular
Nitrogenase/química
Ligação Proteica
Conformação Proteica
Proteólise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Flavodoxin); 0 (Reducing Agents); E1UOL152H7 (Iron); EC 1.18.6.1 (Nitrogenase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171009
[Lr] Data última revisão:
171009
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170809
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.801548


  5 / 1231 MEDLINE  
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[PMID]:28759456
[Au] Autor:Mohamed HD; Mansour B; Nasr-Eddine B
[Ad] Endereço:Laboratoire de Rhéologie, Transport et Traitement des Fluides Complexes (LRTTFC), Faculté d'Architecture et de Génie Civil, Département d'Hydraulique, Université des Sciences et de la Technologie d'Oran « Mohamed Boudiaf ¼, BP1505 El-M'naouar, Oran 31036, Algérie E-mail: hadji31med@gmail.com; mohamed.hadj@univ-usto.dz.
[Ti] Título:Experimental study of using wastewater sludge as a new drag reduction agent.
[So] Source:Water Sci Technol;76(3-4):739-746, 2017 Jul.
[Is] ISSN:0273-1223
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Siltation is considering as a huge risk to the life and security of dams. Forced to preserve their useful volumes, managers use sediment dredging operations through different techniques. The aim of our work is to investigate the wastewater sludge derived from wastewater treatment as a new natural lubricating instrument during transport of sediment in the pipes and to reduce head losses. From an economic and environmental point of view, this technique is more effective than the use of industrial polymers. The rheological study is done using an RS600 rheometer. Head losses and friction reducing are measured on three horizontal pipes (30, 50 and 80 mm). The mud from the dam and sludge are added at different volumes concentrations. The results revealed that the mud follows the Herschel-Bulkley model at 10-20% volume concentration, even after adding wastewater sludge proportions from 0.1- 0.4%. The mud flow head losses in pipes increase with increasing solids concentration. A maximum reduction in yield stress and frictional head loss are observed at 0.25 to 0.35% of sludge concentration, which can be the most effective choice.
[Mh] Termos MeSH primário: Esgotos
Águas Residuais
[Mh] Termos MeSH secundário: Substâncias Redutoras
Reologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Reducing Agents); 0 (Sewage); 0 (Waste Water)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170801
[St] Status:MEDLINE
[do] DOI:10.2166/wst.2017.233


  6 / 1231 MEDLINE  
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[PMID]:28473295
[Au] Autor:Sakurai T; Yamamoto M; Ikeno S; Kataoka K
[Ad] Endereço:Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan. Electronic address: tasakura@staff.kanazawa-u.ac.jp.
[Ti] Título:Amino acids located in the outer-sphere of the trinuclear copper center in a multicopper oxidase, CueO as the putative electron donor in the four-electron reduction of dioxygen.
[So] Source:Biochim Biophys Acta;1865(8):997-1003, 2017 08.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The reaction mechanism of multicopper oxidase (MCO) to reduce dioxygen to water has not been fully understood yet in spite of extensive studies including on the intermediate I (peroxide intermediate) and intermediate II (native intermediate with an O-centered structure at the trinuclear copper center (TNC)). We performed the Phe mutations at the four amino acids, Tyr69, Cys138, Trp139, and Tyr496 located in the outer-sphere of TNC in CueO at the aim of studying whether they play a role as the fourth electron donor to dioxygen or not. Spectral properties and enzymatic activities of CueO were sparingly affected or not affected by the mutations at these putative electron donors. Of the targeted four amino acids Trp139 is in a d-π interaction distance with one of T3Cus and drives stepwise formation and release of water molecules by making two T3Cus non-equivalent. However, contribution of a radical species derived from Trp139 has not been observed in the formation and decay processes of the reaction intermediates. The present study strongly suggests that the amino acids located in the outer-sphere of TNC are not utilized as electron donor in the reduction of dioxygen to water by the three-domain MCO, CueO, differing from cytochrome oxidase and SLAC, a two-domain MCO, in which reaction participation of an uncoordinated Tyr residue has been proposed. SUMMARY: We performed the Phe mutations at the four amino acids, Tyr69, Cys138, Trp139 and Tyr496 located in the outer-coordination sphere of the trinuclear copper center in a three-domain multicopper oxidase, CueO to ascertain whether they function as an electron donor or not in the four-electron reduction of dioxygen. Characterizations of the mutants and reactions did not suggest participation of the targeted amino acids, indicating that CueO follows a different reaction mechanism from that of a two-domain multicopper oxidase, SLAC, in which reaction participation of an uncoordinated Tyr has been suggested.
[Mh] Termos MeSH primário: Aminoácidos/metabolismo
Cobre/metabolismo
Oxirredutases/metabolismo
Oxigênio/metabolismo
Substâncias Redutoras/metabolismo
[Mh] Termos MeSH secundário: Sítios de Ligação/fisiologia
Elétrons
Escherichia coli/metabolismo
Proteínas de Escherichia coli/metabolismo
Modelos Moleculares
Mutação/genética
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Amino Acids); 0 (Escherichia coli Proteins); 0 (Reducing Agents); 789U1901C5 (Copper); EC 1.- (Oxidoreductases); EC 1.16.- (copper oxidase); S88TT14065 (Oxygen)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170506
[St] Status:MEDLINE


  7 / 1231 MEDLINE  
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[PMID]:28237574
[Au] Autor:Sivaranjana P; Nagarajan ER; Rajini N; Jawaid M; Rajulu AV
[Ad] Endereço:Department of Chemistry, Kalasalingam University, Krishnankoil 626126, Tamil Nadu, India.
[Ti] Título:Cellulose nanocomposite films with in situ generated silver nanoparticles using Cassia alata leaf extract as a reducing agent.
[So] Source:Int J Biol Macromol;99:223-232, 2017 Jun.
[Is] ISSN:1879-0003
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Cotton linters were dissolved in aq. (8% LiOH+15% urea) that was pre-cooled to -12.5°C. Using this solution cellulose gel films were prepared by regeneration method with ethyl alcohol as a coagulant. These wet films were diffused with 10wt% Cassia alata leaf extract that acted as a reducing agent. The leaf extract diffused cellulose wet films were used as the matrix. The wet matrix films were dipped individually in lower concentrated 1-5mM aq.AgNO source solutions in the presence of sunlight and allowed the solutions to react with the diffused leaf extract reducing agent which in situ generated the silver nanoparticles (AgNPs) inside the films as well as in the source solution. The AgNPs formed in the source solution were observed by transmission electron microscope (TEM) and scanning electron microscope (SEM) while those formed in situ the films were observed by SEM and the particle size distribution was determined. The cellulose/AgNP composite films showed good antibacterial activity against Escherichia coli bacteria. These nanocomposite films were also characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA) and tensile tests. At temperatures below 300°C, the thermal stability of the nanocomposite films was lower than that of the matrix due to the catalytic effect of AgNPs. The nanocomposite films also possessed good tensile properties. The ecofriendly cellulose/AgNP composite films with good antibacterial activity and tensile properties can be considered for medical applications like dressing materials.
[Mh] Termos MeSH primário: Cassia/química
Celulose/química
Nanopartículas Metálicas/química
Nanocompostos/química
Extratos Vegetais/química
Folhas de Planta/química
Prata/química
[Mh] Termos MeSH secundário: Antibacterianos/química
Antibacterianos/farmacologia
Celulose/farmacologia
Nanotecnologia
Substâncias Redutoras/química
Temperatura Ambiente
Resistência à Tração
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Plant Extracts); 0 (Reducing Agents); 3M4G523W1G (Silver); 9004-34-6 (Cellulose)
[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:170227
[St] Status:MEDLINE


  8 / 1231 MEDLINE  
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[PMID]:28212725
[Au] Autor:Gaschler MM; Stockwell BR
[Ad] Endereço:Department of Chemistry, Columbia University, 550 West 120th Street, Northwest Corner Building, MC 4846, New York, NY 10027, USA.
[Ti] Título:Lipid peroxidation in cell death.
[So] Source:Biochem Biophys Res Commun;482(3):419-425, 2017 Jan 15.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Disruption of redox homeostasis is a key phenotype of many pathological conditions. Though multiple oxidizing compounds such as hydrogen peroxide are widely recognized as mediators and inducers of oxidative stress, increasingly, attention is focused on the role of lipid hydroperoxides as critical mediators of death and disease. As the main component of cellular membranes, lipids have an indispensible role in maintaining the structural integrity of cells. Excessive oxidation of lipids alters the physical properties of cellular membranes and can cause covalent modification of proteins and nucleic acids. This review discusses the synthesis, toxicity, degradation, and detection of lipid peroxides in biological systems. Additionally, the role of lipid peroxidation is highlighted in cell death and disease, and strategies to control the accumulation of lipid peroxides are discussed.
[Mh] Termos MeSH primário: Morte Celular/fisiologia
Peroxidação de Lipídeos/fisiologia
[Mh] Termos MeSH secundário: Doença de Alzheimer/etiologia
Doença de Alzheimer/metabolismo
Animais
Morte Celular/efeitos dos fármacos
Seres Humanos
Peroxidação de Lipídeos/efeitos dos fármacos
Peróxidos Lipídicos/metabolismo
Peróxidos Lipídicos/toxicidade
Inibidores de Lipoxigenase/farmacologia
Redes e Vias Metabólicas
Oxirredução
Substâncias Redutoras/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Lipid Peroxides); 0 (Lipoxygenase Inhibitors); 0 (Reducing Agents)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170523
[Lr] Data última revisão:
170523
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170219
[St] Status:MEDLINE


  9 / 1231 MEDLINE  
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[PMID]:28130140
[Au] Autor:Retnoningrum DS; Arumsari S; Artarini A; Ismaya WT
[Ad] Endereço:Laboratory of Pharmaceutical Biotechnology, School of Pharmacy, Bandung Institute of Technology, Jalan Ganesa No. 10, Bandung, 40132, Indonesia. Electronic address: retnoningrum@indo.net.id.
[Ti] Título:Structure-activity relationship of a recombinant hybrid Manganese superoxide dismutase of Staphylococcus saprophyticus/S. equorum.
[So] Source:Int J Biol Macromol;98:222-227, 2017 May.
[Is] ISSN:1879-0003
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Recombinant hybrid Manganese superoxide dismutase from Staphyloccus saphropyticus/S. equorum (rMnSODSeq) exhibits stability at high temperatures. The enzyme occurs as a dimer that dissociates around 52°C prior to unfolding of the monomer around 64°C, demonstrating contribution of the dimeric form to stability. Here, structure - activity relationship of rMnSODSeq was evaluated on the basis of its activity and stability in the presence of inhibitors, NaCl, denaturants, detergents, reducing agents, and at different pH values. The activity was evaluated at both 37°C and 52°C, which the latter is the temperature for dissociation of the dimer. Dimer to monomer transition coincided with significant decrease in residual activity at 52°C. However, the activity assay results at 52°C and 37°C suggest spontaneous re-association of the monomer into dimer. Intriguingly, various new species with melting temperature (T ) values other than those of the dimer or monomer were observed. These species displayed medium to comparable level of residual activities to the native at 37°C. This report suggests that dimer to monomer transition may be not the only explanation for activity loss or decrease.
[Mh] Termos MeSH primário: Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
Staphylococcus saprophyticus/enzimologia
Superóxido Dismutase/química
Superóxido Dismutase/metabolismo
[Mh] Termos MeSH secundário: Detergentes/farmacologia
Inibidores Enzimáticos/farmacologia
Concentração de Íons de Hidrogênio
Desnaturação Proteica/efeitos dos fármacos
Substâncias Redutoras/farmacologia
Cloreto de Sódio/farmacologia
Relação Estrutura-Atividade
Superóxido Dismutase/antagonistas & inibidores
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Detergents); 0 (Enzyme Inhibitors); 0 (Recombinant Proteins); 0 (Reducing Agents); 451W47IQ8X (Sodium Chloride); EC 1.15.1.1 (Superoxide Dismutase)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170426
[Lr] Data última revisão:
170426
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170129
[St] Status:MEDLINE


  10 / 1231 MEDLINE  
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[PMID]:28054271
[Au] Autor:Naseem K; Begum R; Farooqi ZH
[Ad] Endereço:Institute of Chemistry, University of the Punjab, New Campus Lahore, Lahore, 54590, Pakistan.
[Ti] Título:Catalytic reduction of 2-nitroaniline: a review.
[So] Source:Environ Sci Pollut Res Int;24(7):6446-6460, 2017 Mar.
[Is] ISSN:1614-7499
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:2-nitroaniline (2-NA) is highly toxic and environmental contaminant. It is reduced to less toxic and environmental benign product o-phenylenediamine by using different reducing agents like sodium borohydride, potassium borohydride, or hydrazine hydrate in the presence of various catalytic systems. These catalytic systems have various advantages and drawbacks. Silica-supported gold nanoparticles are frequently reported catalyst for the reduction of 2-nitroaniline in aqueous medium. In this review article, different catalytic systems reported for reduction of o-nitroaniline under various reaction conditions have been discussed. The critical review of the recent research progress for development of novel catalysts used for the reduction of 2-nitroaniline has been provided here.
[Mh] Termos MeSH primário: Compostos de Anilina/química
Poluentes Ambientais/química
Substâncias Redutoras/química
[Mh] Termos MeSH secundário: Catálise
Recuperação e Remediação Ambiental
Seres Humanos
Nanopartículas Metálicas/química
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (2-nitroaniline); 0 (Aniline Compounds); 0 (Environmental Pollutants); 0 (Reducing Agents)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171104
[Lr] Data última revisão:
171104
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170106
[St] Status:MEDLINE
[do] DOI:10.1007/s11356-016-8317-2



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