Base de dados : MEDLINE
Pesquisa : D08.244.300 [Categoria DeCS]
Referências encontradas : 99 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 10 ir para página                        

  1 / 99 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27999164
[Au] Autor:Jones-Carson J; Husain M; Liu L; Orlicky DJ; Vázquez-Torres A
[Ad] Endereço:Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, Colorado, USA.
[Ti] Título:Cytochrome bd-Dependent Bioenergetics and Antinitrosative Defenses in Salmonella Pathogenesis.
[So] Source:MBio;7(6), 2016 Dec 20.
[Is] ISSN:2150-7511
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In the course of an infection, Salmonella enterica occupies diverse anatomical sites with various concentrations of oxygen (O ) and nitric oxide (NO). These diatomic gases compete for binding to catalytic metal groups of quinol oxidases. Enterobacteriaceae express two evolutionarily distinct classes of quinol oxidases that differ in affinity for O and NO as well as stoichiometry of H translocated across the cytoplasmic membrane. The investigations presented here show that the dual function of bacterial cytochrome bd in bioenergetics and antinitrosative defense enhances Salmonella virulence. The high affinity of cytochrome bd for O optimizes respiratory rates in hypoxic cultures, and thus, this quinol oxidase maximizes bacterial growth under O -limiting conditions. Our investigations also indicate that cytochrome bd, rather than cytochrome bo, is an intrinsic component of the adaptive antinitrosative toolbox of Salmonella Accordingly, induction of cytochrome bd helps Salmonella grow and respire in the presence of inhibitory NO. The combined antinitrosative defenses of cytochrome bd and the flavohemoglobin Hmp account for a great part of the adaptations that help Salmonella recover from the antimicrobial activity of NO. Moreover, the antinitrosative defenses of cytochrome bd and flavohemoglobin Hmp synergize to promote Salmonella growth in systemic tissues. Collectively, our investigations indicate that cytochrome bd is a critical means by which Salmonella resists the nitrosative stress that is engendered in the innate response of mammalian hosts while it concomitantly allows for proper O utilization in tissue hypoxia. IMPORTANCE: It is becoming quite apparent that metabolism is critically important to the virulence potential of pathogenic microorganisms. Bacterial cells use a variety of terminal electron acceptors to power electron transport chains and metabolic processes. Of all the electron acceptors available to bacteria, utilization of O yields the most energy while diversifying the type of substrates that a pathogen can use. Recent investigations have demonstrated important roles for bd-type quinol oxidases with high affinity for O in bacterial pathogenesis. The investigations presented here have revealed that cytochrome bd potentiates virulence of a clinically relevant bacterial pathogen by fueling bioenergetics of prokaryotic cells while protecting the respiratory chain against NO toxicity. The adaptive antinitrosative defenses afforded by cytochrome bd synergize with other NO-detoxifying systems to preserve cellular bioenergetics, thereby promoting bacterial virulence in tissue hypoxia.
[Mh] Termos MeSH primário: Grupo dos Citocromos b/metabolismo
Grupo dos Citocromos d/metabolismo
Metabolismo Energético
Óxido Nítrico/metabolismo
Oxigênio/metabolismo
Salmonella enterica/metabolismo
Salmonella enterica/patogenicidade
[Mh] Termos MeSH secundário: Animais
Complexo de Proteínas da Cadeia de Transporte de Elétrons
Seres Humanos
Hipóxia
Imunidade Inata
Oxirredução
Oxirredutases/metabolismo
Consumo de Oxigênio
Salmonella enterica/crescimento & desenvolvimento
Estresse Fisiológico
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cytochrome b Group); 0 (Electron Transport Chain Complex Proteins); 31C4KY9ESH (Nitric Oxide); 9035-36-3 (Cytochrome d Group); EC 1.- (Oxidoreductases); EC 1.- (duroquinol oxidase); S88TT14065 (Oxygen)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170721
[Lr] Data última revisão:
170721
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161222
[St] Status:MEDLINE


  2 / 99 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27126043
[Au] Autor:Safarian S; Rajendran C; Müller H; Preu J; Langer JD; Ovchinnikov S; Hirose T; Kusumoto T; Sakamoto J; Michel H
[Ad] Endereço:Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Max-von-Laue-Straße 3, D-60438 Frankfurt/Main, Germany.
[Ti] Título:Structure of a bd oxidase indicates similar mechanisms for membrane-integrated oxygen reductases.
[So] Source:Science;352(6285):583-6, 2016 Apr 29.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The cytochrome bd oxidases are terminal oxidases that are present in bacteria and archaea. They reduce molecular oxygen (dioxygen) to water, avoiding the production of reactive oxygen species. In addition to their contribution to the proton motive force, they mediate viability under oxygen-related stress conditions and confer tolerance to nitric oxide, thus contributing to the virulence of pathogenic bacteria. Here we present the atomic structure of the bd oxidase from Geobacillus thermodenitrificans, revealing a pseudosymmetrical subunit fold. The arrangement and order of the heme cofactors support the conclusions from spectroscopic measurements that the cleavage of the dioxygen bond may be mechanistically similar to that in the heme-copper-containing oxidases, even though the structures are completely different.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Grupo dos Citocromos d/química
Citocromos b/química
Complexo IV da Cadeia de Transporte de Elétrons/química
Geobacillus/enzimologia
Oxigênio/química
[Mh] Termos MeSH secundário: Proteínas de Bactérias/ultraestrutura
Grupo dos Citocromos d/ultraestrutura
Citocromos b/ultraestrutura
Complexo IV da Cadeia de Transporte de Elétrons/ultraestrutura
Dobramento de Proteína
Estrutura Secundária de Proteína
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 9035-36-3 (Cytochrome d Group); 9035-37-4 (Cytochromes b); EC 1.9.3.1 (Electron Transport Complex IV); S88TT14065 (Oxygen)
[Em] Mês de entrada:1605
[Cu] Atualização por classe:170720
[Lr] Data última revisão:
170720
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160430
[St] Status:MEDLINE
[do] DOI:10.1126/science.aaf2477


  3 / 99 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27126025
[Au] Autor:Cook GM; Poole RK
[Ad] Endereço:Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago, Dunedin 9054, New Zealand. Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland 1042, New Zealand. greg.cook@otago.ac.nz.
[Ti] Título:BIOCHEMISTRY. A bacterial oxidase like no other?
[So] Source:Science;352(6285):518-9, 2016 Apr 29.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Grupo dos Citocromos d/química
Citocromos b/química
Complexo IV da Cadeia de Transporte de Elétrons/química
Geobacillus/enzimologia
Oxigênio/química
[Pt] Tipo de publicação:COMMENT; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 9035-36-3 (Cytochrome d Group); 9035-37-4 (Cytochromes b); EC 1.9.3.1 (Electron Transport Complex IV); S88TT14065 (Oxygen)
[Em] Mês de entrada:1605
[Cu] Atualização por classe:170720
[Lr] Data última revisão:
170720
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160430
[St] Status:MEDLINE
[do] DOI:10.1126/science.aaf5514


  4 / 99 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:20730594
[Au] Autor:Zhang H; Setubal JC; Zhan X; Zheng Z; Yu L; Wu J; Chen D
[Ad] Endereço:Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
[Ti] Título:Component identification of electron transport chains in curdlan-producing Agrobacterium sp. ATCC 31749 and its genome-specific prediction using comparative genome and phylogenetic trees analysis.
[So] Source:J Ind Microbiol Biotechnol;38(6):667-77, 2011 Jun.
[Is] ISSN:1476-5535
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Agrobacterium sp. ATCC 31749 (formerly named Alcaligenes faecalis var. myxogenes) is a non-pathogenic aerobic soil bacterium used in large scale biotechnological production of curdlan. However, little is known about its genomic information. DNA partial sequence of electron transport chains (ETCs) protein genes were obtained in order to understand the components of ETC and genomic-specificity in Agrobacterium sp. ATCC 31749. Degenerate primers were designed according to ETC conserved sequences in other reported species. DNA partial sequences of ETC genes in Agrobacterium sp. ATCC 31749 were cloned by the PCR method using degenerate primers. Based on comparative genomic analysis, nine electron transport elements were ascertained, including NADH ubiquinone oxidoreductase, succinate dehydrogenase complex II, complex III, cytochrome c, ubiquinone biosynthesis protein ubiB, cytochrome d terminal oxidase, cytochrome bo terminal oxidase, cytochrome cbb (3)-type terminal oxidase and cytochrome caa (3)-type terminal oxidase. Similarity and phylogenetic analyses of these genes revealed that among fully sequenced Agrobacterium species, Agrobacterium sp. ATCC 31749 is closest to Agrobacterium tumefaciens C58. Based on these results a comprehensive ETC model for Agrobacterium sp. ATCC 31749 is proposed.
[Mh] Termos MeSH primário: Rhizobium/genética
beta-Glucanas/metabolismo
[Mh] Termos MeSH secundário: Grupo dos Citocromos d/genética
Transporte de Elétrons/genética
Complexo IV da Cadeia de Transporte de Elétrons/genética
Genes Bacterianos
Genoma Bacteriano
Genômica
Oxirredutases/genética
Filogenia
Rhizobium/classificação
Rhizobium/enzimologia
Succinato Desidrogenase/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (beta-Glucans); 6930DL209R (curdlan); 9035-36-3 (Cytochrome d Group); EC 1.- (Oxidoreductases); EC 1.3.99.1 (Succinate Dehydrogenase); EC 1.9.3.- (cytochrome o oxidase); EC 1.9.3.1 (Electron Transport Complex IV)
[Em] Mês de entrada:1108
[Cu] Atualização por classe:171014
[Lr] Data última revisão:
171014
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:100824
[St] Status:MEDLINE
[do] DOI:10.1007/s10295-010-0810-x


  5 / 99 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:20541114
[Au] Autor:Kishikawa J; Kabashima Y; Kurokawa T; Sakamoto J
[Ad] Endereço:Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, Kawazu 680-4, Iizuka, Fukuoka, 820-8502, Japan.
[Ti] Título:The cytochrome bcc-aa3-type respiratory chain of Rhodococcus rhodochrous.
[So] Source:J Biosci Bioeng;110(1):42-7, 2010 Jul.
[Is] ISSN:1347-4421
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Rhodococcus rhodochrous is an active soil bacterium belonging to the Nocardia group of high GC gram-positive bacteria. It is rich in various enzymes and thus important in the industrial production of chemicals and bioremediation. In this work, the respiratory chain of this aerobic organism was investigated and characterized. Grown under highly aerobic conditions, the membrane fraction of R. rhodochrous cells only contained a-, b- and c-type cytochromes, suggesting that it is the cytochrome bcc-aa(3)-type pathway that mainly operates under these conditions. In contrast, the d-type cytochrome was also present under microaerobic conditions, indicating that the alternative pathway of the bd-type oxidase works in these circumstances. In addition, the results of H(+)/O ratio measurements indicate that these two pathways have different energy efficiencies.
[Mh] Termos MeSH primário: Complexo IV da Cadeia de Transporte de Elétrons/metabolismo
Rhodococcus/enzimologia
[Mh] Termos MeSH secundário: Aerobiose/fisiologia
Membrana Celular/química
Grupo dos Citocromos c/metabolismo
Grupo dos Citocromos d/metabolismo
Citocromos/análise
Citocromos/metabolismo
Transporte de Elétrons/fisiologia
Complexo IV da Cadeia de Transporte de Elétrons/química
Metabolismo Energético/fisiologia
Inibidores Enzimáticos/farmacologia
Concentração de Íons de Hidrogênio
Oxirredução
Oxirredutases/metabolismo
Oxigênio/metabolismo
Rhodococcus/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cytochrome c Group); 0 (Cytochromes); 0 (Enzyme Inhibitors); 9035-36-3 (Cytochrome d Group); EC 1.- (Oxidoreductases); EC 1.9.3.1 (Electron Transport Complex IV); S88TT14065 (Oxygen)
[Em] Mês de entrada:1008
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:100615
[St] Status:MEDLINE
[do] DOI:10.1016/j.jbiosc.2009.12.006


  6 / 99 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
PubMed Central Texto completo
Texto completo
[PMID]:20392690
[Au] Autor:Shepherd M; Sanguinetti G; Cook GM; Poole RK
[Ad] Endereço:Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom.
[Ti] Título:Compensations for diminished terminal oxidase activity in Escherichia coli: cytochrome bd-II-mediated respiration and glutamate metabolism.
[So] Source:J Biol Chem;285(24):18464-72, 2010 Jun 11.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Escherichia coli possesses cytochrome bo' (CyoABCDE), cytochrome bd-I (CydAB), and cytochrome bd-II (AppBC) quinol oxidases, all of which can catalyze the terminal step in the aerobic respiratory chain, the reduction of oxygen by ubiquinol. Although CydAB has a role in the generation of DeltapH, AppBC has been proposed to alleviate the accumulation of electrons in the quinone pool during respiratory stress via electroneutral ubiquinol oxidation. A cydB mutant strain exhibited lower respiration rates while maintaining a wild type growth rate. Transcriptomic analysis revealed a dramatic up-regulation of AppBC in the cydB strain, accompanied by the induction of genes involved in glutamate/gamma-aminobutyric acid (GABA) antiport, the GABA shunt, the glyoxylate shunt, respiration (including appBC), motility, and osmotic stress. Transcription factor modeling suggests that the underpinning regulation is largely controlled by H-NS, GadX, FlhDC, and AppY. The transcriptional adaptations imply that cydB cells contribute to the proton motive force via consumption of intracellular protons and glutamate/GABA antiport. Indeed, supplementation of culture medium with l-glutamate stimulates growth in a cydB strain. Phenotype analyses of the cydB strain confirm decreased motility and elevated acid resistance and also an elevated cytochrome d spectroscopic signal in cells grown at low pH. We propose a mechanism via which E. coli can compensate for the loss of cytochrome bd-I activity; cytochrome bd-II-mediated quinol oxidation prevents the accumulation of NADH, whereas GABA synthesis/antiport maintains the proton motive force for ATP production.
[Mh] Termos MeSH primário: Grupo dos Citocromos d/genética
Citocromos b/genética
Escherichia coli/enzimologia
Ácido Glutâmico/metabolismo
Consumo de Oxigênio
[Mh] Termos MeSH secundário: Movimento Celular
Respiração Celular
Eletrodos
Regulação Bacteriana da Expressão Gênica
Glutamatos/química
Concentração de Íons de Hidrogênio
Cinética
Modelos Estatísticos
Oxigênio/química
Espectrofotometria/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Glutamates); 3KX376GY7L (Glutamic Acid); 9035-36-3 (Cytochrome d Group); 9035-37-4 (Cytochromes b); S88TT14065 (Oxygen)
[Em] Mês de entrada:1006
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:100416
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M110.118448


  7 / 99 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
PubMed Central Texto completo
Texto completo
[PMID]:19897650
[Au] Autor:Alvarez AF; Malpica R; Contreras M; Escamilla E; Georgellis D
[Ad] Endereço:Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Mexico, Mexico.
[Ti] Título:Cytochrome d but not cytochrome o rescues the toluidine blue growth sensitivity of arc mutants of Escherichia coli.
[So] Source:J Bacteriol;192(2):391-9, 2010 Jan.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The Arc (anoxic redox control) two-component signal transduction system, consisting of the ArcB sensor kinase and the ArcA response regulator, allows adaptive responses of Escherichia coli to changes of O(2) availability. The arcA gene was previously known as the dye gene because null mutants were growth sensitive to the photosensitizer redox dyes toluidine blue and methylene blue, a phenotype whose molecular basis still remains elusive. In this study we report that the toluidine blue O (TBO) effect on the arc mutants is light independent and observed only during aerobic growth conditions. Moreover, 16 suppressor mutants with restored growth were generated and analyzed. Thirteen of those possessed insertion elements upstream of the cydAB operon, rendering its expression ArcA independent. Also, it was found that, in contrast to cythocrome d, cythocrome o was not able to confer toluidine blue resistance to arc mutants, thereby representing an intriguing difference between the two terminal oxidases. Finally, a mechanism for TBO sensitivity and resistance is discussed.
[Mh] Termos MeSH primário: Proteínas da Membrana Bacteriana Externa/genética
Grupo dos Citocromos b/metabolismo
Grupo dos Citocromos d/metabolismo
Citocromos/metabolismo
Proteínas de Escherichia coli/metabolismo
Escherichia coli/efeitos dos fármacos
Escherichia coli/crescimento & desenvolvimento
Proteínas Repressoras/genética
Cloreto de Tolônio/farmacologia
[Mh] Termos MeSH secundário: Anaerobiose
Proteínas da Membrana Bacteriana Externa/metabolismo
Sequência de Bases
Carotenoides/metabolismo
Catalase/metabolismo
Corantes/farmacologia
Grupo dos Citocromos b/genética
Grupo dos Citocromos d/genética
Citocromos/genética
Escuridão
Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética
Escherichia coli/genética
Escherichia coli/metabolismo
Proteínas de Escherichia coli/genética
Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos
Regulação Bacteriana da Expressão Gênica/genética
Regulação Bacteriana da Expressão Gênica/efeitos da radiação
Glucose/farmacologia
Luz
Dados de Sequência Molecular
Mutação/genética
Oxirredutases/genética
Regiões Promotoras Genéticas/genética
Espécies Reativas de Oxigênio/metabolismo
Proteínas Repressoras/metabolismo
Homologia de Sequência do Ácido Nucleico
Superóxido Dismutase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Coloring Agents); 0 (Cytochrome b Group); 0 (Cytochromes); 0 (Electron Transport Chain Complex Proteins); 0 (Escherichia coli Proteins); 0 (Reactive Oxygen Species); 0 (Repressor Proteins); 0 (arcA protein, E coli); 15XUH0X66N (Tolonium Chloride); 36-88-4 (Carotenoids); 9035-36-3 (Cytochrome d Group); 9035-48-7 (cytochrome bo, E coli); EC 1.- (Oxidoreductases); EC 1.11.1.6 (Catalase); EC 1.15.1.1 (Superoxide Dismutase); EC 1.9.3.- (cytochrome bd terminal oxidase complex, E coli); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1001
[Cu] Atualização por classe:141204
[Lr] Data última revisão:
141204
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:091110
[St] Status:MEDLINE
[do] DOI:10.1128/JB.00881-09


  8 / 99 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:18457966
[Au] Autor:Santana M
[Ad] Endereço:ICAT-Instituto de Ciência Aplicada e Tecnologia, Campo Grande, 1749-016 Lisboa, Portugal. msantana@irnase.csic.es
[Ti] Título:Presence and expression of terminal oxygen reductases in strictly anaerobic sulfate-reducing bacteria isolated from salt-marsh sediments.
[So] Source:Anaerobe;14(3):145-56, 2008 Jun.
[Is] ISSN:1075-9964
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In the anaerobic sulfate-reducing bacterium Desulfovibrio vulgaris Hildenborough genes were found encoding membrane terminal oxygen reductases of two types: a cytochrome c oxidase and a cytochrome bd oxidase, both enzymes are terminal oxidases typical of facultative or aerobic microorganisms (Heidelberg JF, et al., The genome sequence of the anaerobic, sulfate-reducing bacterium D. vulgaris Hildenborough. Nat Biotechnol 2004; 22: 554-9). To apprehend the presence of both oxidases in other sulfate-reducing bacteria (SRB), several assays were performed on isolates recovered from salt-marsh sediments in Portugal, representative of the different phylogenetic groups identified. Hybridization and PCR experiments for DNA sequencing were performed on the chosen isolates. Primers were selected to amplify conserved regions of cytochrome c oxidases and cytochrome bd oxidases taking into consideration alignment of corresponding subunit I sequences. The results showed that both oxidase genes are present on the chromosome of several isolates characterized as Desulfovibrio. These genes were shown to be transcribed, as demonstrated by Reverse Transcriptase-PCR experiments on total RNA. In order to assess the relative contribution of each oxidase to oxygen consumption, oxygen uptake was measured for each isolate and further characterized by the effect of cyanide on oxygen consumption. It was concluded that cytochrome bd oxidase was the terminal membrane oxygen reductase allowing oxygen consumption. In addition, it was observed that isolates containing cytochrome bd oxidase had higher resistance to air exposure, suggesting an important role of this enzyme in survival to air exposure. The pattern for the presence of oxygen reductase genes was compared to the physiological pattern of substrate use, which was determined for each isolate. Salinity tolerance, pH and temperature growth of each isolate were also analyzed.
[Mh] Termos MeSH primário: Desulfovibrio vulgaris/enzimologia
Sedimentos Geológicos/microbiologia
Oxirredutases/metabolismo
Oxigênio/metabolismo
Água do Mar/microbiologia
Bactérias Redutoras de Enxofre/enzimologia
[Mh] Termos MeSH secundário: Anaerobiose
Grupo dos Citocromos d/genética
Grupo dos Citocromos d/metabolismo
Citocromos b/genética
Citocromos b/metabolismo
Desulfovibrio vulgaris/genética
Desulfovibrio vulgaris/crescimento & desenvolvimento
Desulfovibrio vulgaris/isolamento & purificação
Complexo IV da Cadeia de Transporte de Elétrons/genética
Complexo IV da Cadeia de Transporte de Elétrons/metabolismo
Dados de Sequência Molecular
Oxirredutases/genética
Oxigênio/farmacologia
Consumo de Oxigênio
Filogenia
Portugal
Análise de Sequência de DNA
Bactérias Redutoras de Enxofre/genética
Bactérias Redutoras de Enxofre/crescimento & desenvolvimento
Bactérias Redutoras de Enxofre/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
9035-36-3 (Cytochrome d Group); 9035-37-4 (Cytochromes b); EC 1.- (Oxidoreductases); EC 1.9.3.1 (Electron Transport Complex IV); S88TT14065 (Oxygen)
[Em] Mês de entrada:0808
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:080507
[St] Status:MEDLINE
[do] DOI:10.1016/j.anaerobe.2008.03.001


  9 / 99 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:18420022
[Au] Autor:Gong H; Tang Y; Wang J; Wen X; Zhang L; Lu C
[Ad] Endereço:Photosynthesis Research Center, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
[Ti] Título:Characterization of photosystem II in salt-stressed cyanobacterial Spirulina platensis cells.
[So] Source:Biochim Biophys Acta;1777(6):488-95, 2008 Jun.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:PSII activity was inhibited after Spirulina platensis cells were incubated with different salt concentrations (0-0.8 M NaCl) for 12 h. Flash-induced fluorescence kinetics showed that in the absence of DCMU, the half time of the fast and slow components decreased while that of the middle component increased considerably with increasing salt concentration. In the presence of DCMU, fluorescence relaxation was dominated by a 0.6s component in control cells. After salt stress, this was partially replaced by a faster new component with half time of 20-50 ms. Thermoluminescence measurements revealed that S(2)Q(A)(-) and S(2)Q(B)(-) recombinations were shifted to higher temperatures in parallel and the intensities of the thermoluminescence emissions were significantly reduced in salt-stressed cells. The period-four oscillation of the thermoluminescence B band was highly damped. There were no significant changes in contents of CP47, CP43, cytochrome c550, and D1 proteins. However, content of the PsbO protein in thylakoid fraction decreased but increased significantly in soluble fraction. The results suggest that salt stress leads to a modification of the Q(B) niche at the acceptor side and an increase in the stability of the S(2) state at the donor side, which is associated with a dissociation of the PsbO protein.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Grupo dos Citocromos c/metabolismo
Grupo dos Citocromos d/metabolismo
Complexos de Proteínas Captadores de Luz/metabolismo
Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo
Complexo de Proteína do Fotossistema II/metabolismo
Cloreto de Sódio/farmacologia
Spirulina/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Grupo dos Citocromos c/química
Grupo dos Citocromos d/química
Fluorescência
Temperatura Alta
Cinética
Complexos de Proteínas Captadores de Luz/química
Pressão Osmótica
Complexo de Proteínas do Centro de Reação Fotossintética/química
Complexo de Proteína do Fotossistema II/química
Spirulina/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Cytochrome c Group); 0 (Light-Harvesting Protein Complexes); 0 (Photosynthetic Reaction Center Complex Proteins); 0 (Photosystem II Protein Complex); 0 (photosystem II, chlorophyll binding protein, CP-43); 127137-94-4 (photosystem II, chlorophyll-binding protein, CP-47); 451W47IQ8X (Sodium Chloride); 9035-36-3 (Cytochrome d Group); 9064-80-6 (cytochrome C-550)
[Em] Mês de entrada:0807
[Cu] Atualização por classe:161126
[Lr] Data última revisão:
161126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:080419
[St] Status:MEDLINE
[do] DOI:10.1016/j.bbabio.2008.03.018


  10 / 99 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
[PMID]:17784736
[Au] Autor:Belevich I; Borisov VB; Bloch DA; Konstantinov AA; Verkhovsky MI
[Ad] Endereço:Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, PB 65 (Viikinkaari 1), 00014, Helsinki, Finland.
[Ti] Título:Cytochrome bd from Azotobacter vinelandii: evidence for high-affinity oxygen binding.
[So] Source:Biochemistry;46(39):11177-84, 2007 Oct 02.
[Is] ISSN:0006-2960
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Cytochrome bd from Azotobacter vinelandii is a respiratory quinol oxidase that is highly efficient in reducing intracellular oxygen concentration, thus enabling nitrogen fixation under ambient aerobic conditions. Equilibrium measurements of O2 binding to ferrous heme d in the one-electron-reduced form of the A. vinelandii enzyme give Kd(O2) = 0.5 microM, close to the value for the Escherichia coli cytochrome bd (ca. 0.3 microM); thus, both enzymes have similar, high affinity for oxygen. The reaction of the A. vinelandii cytochrome bd in the one-electron-reduced and fully reduced states with O2 is extremely fast approaching the diffusion-controlled limit in water. In the fully reduced state, the rate of O2 binding depends linearly on the oxygen concentration consistently with a simple, single-step process. In contrast, in the one-electron-reduced state the rate of oxygen binding is hyperbolic, implying a more complex binding pattern. Two possible explanations for the saturation kinetics are considered: (A) There is a spectroscopically silent prebinding of oxygen to an unidentified low-affinity saturatable site followed by the oxygen transfer to heme d. (B) Oxygen binding to heme d requires an "activated" state of the enzyme in which an oxygen channel connecting heme d to the bulk is open. This channel is permanently open in the fully reduced enzyme (hence no saturation behavior) but flickers between the open and closed states in the one-electron-reduced enzyme.
[Mh] Termos MeSH primário: Azotobacter vinelandii/metabolismo
Proteínas de Bactérias/metabolismo
Citocromos/metabolismo
Oxigênio/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Ligação Competitiva
Grupo dos Citocromos b/química
Grupo dos Citocromos b/metabolismo
Grupo dos Citocromos d/química
Grupo dos Citocromos d/metabolismo
Citocromos/química
Heme/análogos & derivados
Heme/química
Cinética
Oxirredução
Oxigênio/química
Ligação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Cytochrome b Group); 0 (Cytochromes); 42VZT0U6YR (Heme); 60318-31-2 (heme d); 9035-36-3 (Cytochrome d Group); S88TT14065 (Oxygen)
[Em] Mês de entrada:0712
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:070906
[St] Status:MEDLINE



página 1 de 10 ir para página                        
   


Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde