Base de dados : MEDLINE
Pesquisa : D08.244 [Categoria DeCS]
Referências encontradas : 8373 [refinar]
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[PMID]:29351332
[Au] Autor:Grebenko A; Dremov V; Barzilovich P; Bubis A; Sidoruk K; Voeikova T; Gagkaeva Z; Chernov T; Korostylev E; Gorshunov B; Motovilov K
[Ad] Endereço:Moscow Institute of Physics and Technology, Institute lane 9, Dolgoprudny, Russian Federation.
[Ti] Título:Impedance spectroscopy of single bacterial nanofilament reveals water-mediated charge transfer.
[So] Source:PLoS One;13(1):e0191289, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:For decades respiratory chain and photosystems were the main firing field of the studies devoted to mechanisms of electron transfer in proteins. The concept of conjugated lateral electron and transverse proton transport during cellular respiration and photosynthesis, which was formulated in the beginning of 1960-s, has been confirmed by thousands of experiments. However, charge transfer in recently discovered bacterial nanofilaments produced by various electrogenic bacteria is regarded currently outside of electron and proton conjugation concept. Here we report the new study of charge transfer within nanofilaments produced by Shewanella oneidensis MR-1 conducted in atmosphere of different relative humidity (RH). We utilize impedance spectroscopy and DC (direct current) transport measurements to find out the peculiarities of conductivity and Raman spectroscopy to analyze the nanofilaments' composition. Data analysis demonstrates that apparent conductivity of nanofilaments has crucial sensitivity to humidity and contains several components including one with unusual behavior which we assign to electron transport. We demonstrate that in the case of Shewanella oneidensis MR-1 charge transfer within these objects is strongly mediated by water. Basing on current data analysis of conductivity we conclude that the studied filaments of Shewanella oneidensis MR-1 are capable of hybrid (conjugated) electron and ion conductivity.
[Mh] Termos MeSH primário: Shewanella/metabolismo
Água/metabolismo
[Mh] Termos MeSH secundário: Citocromos/química
Citocromos/metabolismo
Espectroscopia Dielétrica
Transporte de Elétrons
Heme/metabolismo
Umidade
Shewanella/citologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Cytochromes); 059QF0KO0R (Water); 42VZT0U6YR (Heme)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180120
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191289


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[PMID]:29235764
[Au] Autor:Marchenko MM; Ketsa OV; Shmarakov IO; Abutnaritsa KH
[Ti] Título:Monooxygenase system in Guerin's carcinoma of rats under conditions of ω-3 polyunsaturated fatty acids administration.
[So] Source:Ukr Biochem J;88(4):48-56, 2016 Jul-Aug.
[Is] ISSN:2409-4943
[Cp] País de publicação:Ukraine
[La] Idioma:eng
[Ab] Resumo:The aim of the study was to determine the variations of function in components of monooxygenase system (MOS) of rat Guerin's carcinoma under ω-3 polyunsaturated fatty acids (PUFAs) administration. The activity of Guerin's carcinoma microsomal NADH-cytochrome b5 reductase, the content and the rate of cytochrome b5 oxidation-reduction, the content and the rate of cytochrome Р450 oxidation-reduction have been investigated in rats with tumor under conditions of ω-3 PUFAs administration. ω-3 PUFAs supplementation before and after transplantation of Guerin's carcinoma resulted in the increase of NADH-cytochrome b5 reductase activity and decrease of cytochrome b5 level in the Guerin's carcinoma microsomal fraction in the logarithmic phases of carcinogenesis as compared to the tumor-bearing rats. Increased activity of NADH-cytochrome b5 reductase facilitates higher electron flow in redox-chain of MOS. Under decreased cytochrome b5 levels the electrons are transferred to oxygen, which leads to heightened generation of superoxide (O2•-) in comparison to control. It was shown, that the decrease of cytochrome P450 level in the Guerin's carcinoma microsomal fraction in the logarithmic phases of oncogenesis under ω-3 PUFAs administration may be associated with its transition into an inactive form ­ cytochrome P420. This decrease in cytochrome P450 coincides with increased generation of superoxide by MOS oxygenase chain.
[Mh] Termos MeSH primário: Carcinoma/tratamento farmacológico
Elétrons
Ácidos Graxos Ômega-3/farmacologia
Expressão Gênica/efeitos dos fármacos
Microssomos/efeitos dos fármacos
Substâncias Protetoras/farmacologia
[Mh] Termos MeSH secundário: Animais
Carcinoma/enzimologia
Carcinoma/patologia
Sistema Enzimático do Citocromo P-450/genética
Sistema Enzimático do Citocromo P-450/metabolismo
Citocromo-B(5) Redutase/genética
Citocromo-B(5) Redutase/metabolismo
Citocromos/genética
Citocromos/metabolismo
Citocromos b5/genética
Citocromos b5/metabolismo
Transporte de Elétrons/efeitos dos fármacos
Feminino
Membro Posterior
Injeções Subcutâneas
Microssomos/enzimologia
Transplante de Neoplasias
Oxirredução/efeitos dos fármacos
Estresse Oxidativo/efeitos dos fármacos
Ratos
Superóxidos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cytochromes); 0 (Fatty Acids, Omega-3); 0 (Protective Agents); 11062-77-4 (Superoxides); 9035-39-6 (Cytochromes b5); 9035-49-8 (cytochrome P420); 9035-51-2 (Cytochrome P-450 Enzyme System); EC 1.6.2.2 (Cytochrome-B(5) Reductase)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180116
[Lr] Data última revisão:
180116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171214
[St] Status:MEDLINE
[do] DOI:10.15407/ubj88.04.048


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[PMID]:28902850
[Au] Autor:Lavrov AV; Ustaeva OA; Adilgereeva EP; Smirnikhina SA; Chelysheva EY; Shukhov OA; Shatokhin YV; Mordanov SV; Turkina AG; Kutsev SI
[Ad] Endereço:Laboratory of Mutagenesis, Federal State Budgetary Institution Research Centre for Medical Genetics, Moscow, Russian Federation.
[Ti] Título:Copy number variation analysis in cytochromes and glutathione S-transferases may predict efficacy of tyrosine kinase inhibitors in chronic myeloid leukemia.
[So] Source:PLoS One;12(9):e0182901, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Chronic myeloid leukemia (CML) is a myeloproliferative disease characterized by the presence of BCR/ABL fusion gene in leukemic cells, which promotes uncontrolled cell proliferation. Up to 20% of CML patients show primary resistance or non-optimal response to tyrosine kinase inhibitor (TKI) therapy. We investigated the association between copy number variation (CNV) in glutathione S-transferases (GST) and cytochromes (CYP) and the response rate to TKI. We enrolled 47 patients with CML: 31 with an optimal response and 16 with failure at 6 months in accordance with European LeukemiaNet 2013 recommendations. CNV detection was performed using SALSA MLPA P128-C1 Cytochrome P450 probe mix. Patients with optimal response and with failure of TKI therapy showed different frequencies of wild type and mutated CYPs and GST (p<0.0013). Validation in the group of 15 patients proved high prognostic value (p = 0.02): positive and negative predictive value 83% and 78%; sensitivity and specificity 71% and 88%. Wild type genotypes of CYP and GST associate with a worse response to TKI treatment in CML patients. This test can be recommended for further clinical trials.
[Mh] Termos MeSH primário: Citocromos/genética
Variações do Número de Cópias de DNA
Resistência a Medicamentos Antineoplásicos/genética
Glutationa Transferase/genética
Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico
Leucemia Mielogênica Crônica BCR-ABL Positiva/genética
Inibidores de Proteínas Quinases/uso terapêutico
[Mh] Termos MeSH secundário: Adulto
Idoso
Biomarcadores Tumorais/genética
Estudos de Casos e Controles
Feminino
Seres Humanos
Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico
Masculino
Meia-Idade
Prognóstico
Resultado do Tratamento
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biomarkers, Tumor); 0 (Cytochromes); 0 (Protein Kinase Inhibitors); EC 2.5.1.18 (Glutathione Transferase)
[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:170914
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0182901


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[PMID]:28760851
[Au] Autor:Guest RL; Wang J; Wong JL; Raivio TL
[Ad] Endereço:Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
[Ti] Título:A Bacterial Stress Response Regulates Respiratory Protein Complexes To Control Envelope Stress Adaptation.
[So] Source:J Bacteriol;199(20), 2017 Oct 15.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The Cpx envelope stress response mediates adaptation to stresses that affect protein folding within the envelope of Gram-negative bacteria. Recent transcriptome analyses revealed that the Cpx response impacts genes that affect multiple cellular functions predominantly associated with the cytoplasmic membrane. In this study, we examined the connection between the Cpx response and the respiratory complexes NADH dehydrogenase I and cytochrome in enteropathogenic We found that the Cpx response directly represses the transcription of the and operons and that Cpx-mediated repression of these complexes confers adaptation to stresses that compromise envelope integrity. Furthermore, we found that the activity of the aerobic electron transport chain is reduced in lacking a functional Cpx response despite no change in the transcription of either the or the operon. Finally, we show that expression of NADH dehydrogenase I and cytochrome contributes to basal Cpx pathway activity and that overproduction of individual subunits can influence pathway activation. Our results demonstrate that the Cpx response gauges and adjusts the expression, and possibly the function, of inner membrane protein complexes to enable adaptation to envelope stress. Bacterial stress responses allow microbes to survive environmental transitions and conditions, such as those encountered during infection and colonization, that would otherwise kill them. Enteric microbes that inhabit or infect the gut are exposed to a plethora of stresses, including changes in pH, nutrient composition, and the presence of other bacteria and toxic compounds. Bacteria detect and adapt to many of these conditions by using envelope stress responses that measure the presence of stressors in the outermost compartment of the bacterium by monitoring its physiology. The Cpx envelope stress response plays a role in antibiotic resistance and host colonization, and we have shown that it regulates many functions at the bacterial inner membrane. In this report, we describe a novel role for the Cpx response in sensing and controlling the expression of large, multiprotein respiratory complexes at the cytoplasmic membrane of The significance of our research is that it will increase our understanding of how these stress responses are involved in antibiotic resistance and the mechanisms used by bacteria to colonize the gut.
[Mh] Termos MeSH primário: Adaptação Fisiológica
Membrana Celular/fisiologia
Citocromos/metabolismo
Complexo I de Transporte de Elétrons/metabolismo
Escherichia coli Enteropatogênica/fisiologia
Proteínas de Escherichia coli/metabolismo
Regulação Bacteriana da Expressão Gênica
Estresse Fisiológico
[Mh] Termos MeSH secundário: Aerobiose
Transporte de Elétrons
Óperon
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cytochromes); 0 (Escherichia coli Proteins); 0 (cytochrome bo3, E coli); EC 1.6.5.3 (Electron Transport Complex I)
[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:170802
[St] Status:MEDLINE


  5 / 8373 MEDLINE  
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[PMID]:28739829
[Au] Autor:Witola WH; Kim CY; Zhang X
[Ad] Endereço:Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA whwit35@illinois.edu.
[Ti] Título:Inherent Oxidative Stress in the Lewis Rat Is Associated with Resistance to Toxoplasmosis.
[So] Source:Infect Immun;85(10), 2017 Oct.
[Is] ISSN:1098-5522
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The course of infection in rats closely resembles that in humans. However, compared to the Brown Norway (BN) rat, the Lewis (LEW) rat is extremely resistant to infection. Thus, we performed RNA sequencing analysis of the LEW rat versus the BN rat, with or without infection, in order to unravel molecular factors directing robust and rapid early -killing mechanisms in the LEW rat. We found that compared to the uninfected BN rat, the uninfected LEW rat has inherently higher transcript levels of cytochrome enzymes (Cyp2d3, Cyp2d5, and Cybrd1, which catalyze generation of reactive oxygen species [ROS]), with concomitant higher levels of ROS. Interestingly, despite having higher levels of ROS, the LEW rat had lower transcript levels for antioxidant enzymes (lactoperoxidase, microsomal glutathione -transferase 2 and 3, glutathione -transferase peroxidase kappa 1, and glutathione peroxidase) than the BN rat, suggesting that the LEW rat maintains cellular oxidative stress that it tolerates. Corroboratively, we found that scavenging of superoxide anion by Mn(III) tetrakis (4-benzoic acid) porphyrin (MnTBAP) decreased the refractoriness of LEW rat peritoneal cells to infection, resulting in proliferation of parasites in LEW rat peritoneal cells which, in turn, led to augmented cell death in the infected cells. Together, our results indicate that the LEW rat maintains inherent cellular oxidative stress that contributes to resistance to invading , and they thus unveil new avenues for developing therapeutic agents targeting induction of host cell oxidative stress as a mechanism for killing .
[Mh] Termos MeSH primário: Resistência à Doença
Estresse Oxidativo
Toxoplasmose Animal/imunologia
[Mh] Termos MeSH secundário: Animais
Antioxidantes/metabolismo
Morte Celular
Sistema Enzimático do Citocromo P-450/genética
Sistema Enzimático do Citocromo P-450/metabolismo
Citocromos/genética
Glutationa Peroxidase/genética
Glutationa Peroxidase/metabolismo
Glutationa Transferase/genética
Glutationa Transferase/metabolismo
Lactoperoxidase/genética
Lactoperoxidase/metabolismo
Cavidade Peritoneal/parasitologia
Ratos
Ratos Endogâmicos BN
Ratos Endogâmicos Lew
Espécies Reativas de Oxigênio/metabolismo
Análise de Sequência de RNA/métodos
Toxoplasma/imunologia
Toxoplasma/fisiologia
Toxoplasmose Animal/metabolismo
Toxoplasmose Animal/parasitologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antioxidants); 0 (Cytochromes); 0 (Reactive Oxygen Species); 9035-51-2 (Cytochrome P-450 Enzyme System); EC 1.- (Cyp2d3 protein, rat); EC 1.11.1.- (Lactoperoxidase); EC 1.11.1.9 (Glutathione Peroxidase); EC 2.5.1.18 (Glutathione Transferase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170726
[St] Status:MEDLINE


  6 / 8373 MEDLINE  
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[PMID]:28659616
[Au] Autor:Barzi M; Pankowicz FP; Zorman B; Liu X; Legras X; Yang D; Borowiak M; Bissig-Choisat B; Sumazin P; Li F; Bissig KD
[Ad] Endereço:Center for Cell and Gene Therapy, Stem Cells and Regenerative Medicine Center, Baylor College of Medicine, Houston, TX-77030, USA.
[Ti] Título:A novel humanized mouse lacking murine P450 oxidoreductase for studying human drug metabolism.
[So] Source:Nat Commun;8(1):39, 2017 06 28.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Only one out of 10 drugs in development passes clinical trials. Many fail because experimental animal models poorly predict human xenobiotic metabolism. Human liver chimeric mice are a step forward in this regard, as the human hepatocytes in chimeric livers generate human metabolites, but the remaining murine hepatocytes contain an expanded set of P450 cytochromes that form the major class of drug-metabolizing enzymes. We therefore generated a conditional knock-out of the NADPH-P450 oxidoreductase (Por) gene combined with Il2rg /Rag2 /Fah (PIRF) mice. Here we show that homozygous PIRF mouse livers are readily repopulated with human hepatocytes, and when the murine Por gene is deleted (<5%), they predominantly use human cytochrome metabolism. When given the anticancer drug gefitinib or the retroviral drug atazanavir, the Por-deleted humanized PIRF mice develop higher levels of the major human metabolites than current models. Humanized, murine Por-deficient PIRF mice can thus predict human drug metabolism and should be useful for preclinical drug development.Human liver chimeric mice are increasingly used for drug testing in preclinical development, but express residual murine p450 cytochromes. Here the authors generate mice lacking the Por gene in the liver, and show that human cytochrome metabolism is used following repopulation with human hepatocytes.
[Mh] Termos MeSH primário: Sulfato de Atazanavir/metabolismo
Sistema Enzimático do Citocromo P-450/metabolismo
Quinazolinas/metabolismo
[Mh] Termos MeSH secundário: Animais
Antineoplásicos/metabolismo
Quimera
Sistema Enzimático do Citocromo P-450/genética
Citocromos/metabolismo
Feminino
Genótipo
Inibidores da Protease de HIV/metabolismo
Seres Humanos
Fígado/enzimologia
Fígado/metabolismo
Masculino
Camundongos
Camundongos Endogâmicos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Antineoplastic Agents); 0 (Cytochromes); 0 (HIV Protease Inhibitors); 0 (Quinazolines); 4MT4VIE29P (Atazanavir Sulfate); 9035-51-2 (Cytochrome P-450 Enzyme System); S65743JHBS (gefitinib)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171107
[Lr] Data última revisão:
171107
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170630
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-00049-x


  7 / 8373 MEDLINE  
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[PMID]:28634030
[Au] Autor:Li M; Khan S; Rong H; Tuma R; Hatzakis NS; Jeuken LJC
[Ad] Endereço:School of Biomedical Sciences, University of Leeds, LS2 9JT Leeds, UK.
[Ti] Título:Effects of membrane curvature and pH on proton pumping activity of single cytochrome bo enzymes.
[So] Source:Biochim Biophys Acta;1858(9):763-770, 2017 09.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The molecular mechanism of proton pumping by heme-copper oxidases (HCO) has intrigued the scientific community since it was first proposed. We have recently reported a novel technology that enables the continuous characterisation of proton transport activity of a HCO and ubiquinol oxidase from Escherichia coli, cytochrome bo , for hundreds of seconds on the single enzyme level (Li et al. J Am Chem Soc 137 (2015) 16055-16063). Here, we have extended these studies by additional experiments and analyses of the proton transfer rate as a function of proteoliposome size and pH at the N- and P-side of single HCOs. Proton transport activity of cytochrome bo was found to decrease with increased curvature of the membrane. Furthermore, proton uptake at the N-side (proton entrance) was insensitive to pH between pH6.4-8.4, while proton release at the P-side had an optimum pH of ~7.4, suggesting that the pH optimum is related to proton release from the proton exit site. Our previous single-enzyme experiments identified rare, long-lived conformation states of cytochrome bo where protons leak back under turn-over conditions. Here, we analyzed and found that ~23% of cytochrome bo proteoliposomes show ΔpH half-lives below 50s after stopping turnover, while only ~5% of the proteoliposomes containing a non-pumping mutant, E286C cytochrome bo exhibit such fast decays. These single-enzyme results confirm our model in which HCO exhibit heterogeneous pumping rates and can adopt rare leak states in which protons are able to rapidly flow back.
[Mh] Termos MeSH primário: Citocromos/metabolismo
Proteínas de Escherichia coli/metabolismo
Concentração de Íons de Hidrogênio
Proteolipídeos/metabolismo
Bombas de Próton/metabolismo
[Mh] Termos MeSH secundário: Transporte Biológico
Citocromos/genética
Técnicas Eletroquímicas/instrumentação
Transporte de Elétrons
Escherichia coli/enzimologia
Escherichia coli/ultraestrutura
Proteínas de Escherichia coli/genética
Corantes Fluorescentes
Lipossomos/metabolismo
Microscopia de Fluorescência
Oxirredução
Proteolipídeos/ultraestrutura
Bombas de Próton/genética
Prótons
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Cytochromes); 0 (Escherichia coli Proteins); 0 (Fluorescent Dyes); 0 (Liposomes); 0 (Proteolipids); 0 (Proton Pumps); 0 (Protons); 0 (cytochrome bo3, E coli); 0 (proteoliposomes)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171025
[Lr] Data última revisão:
171025
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170622
[St] Status:MEDLINE


  8 / 8373 MEDLINE  
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[PMID]:28235459
[Au] Autor:Choi SK; Lin MT; Ouyang H; Gennis RB
[Ad] Endereço:Center for Biophysics and Quantitative Biology, University of Illinois, Urbana, IL 61801, USA.
[Ti] Título:Searching for the low affinity ubiquinone binding site in cytochrome bo from Escherichia coli.
[So] Source:Biochim Biophys Acta;1858(5):366-370, 2017 05.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The cytochrome bo ubiquinol oxidase is one of three respiratory oxygen reductases in the aerobic respiratory chain of Escherichia coli. The generally accepted model of catalysis assumes that cyt bo contains two distinct ubiquinol binding sites: (i) a low affinity (Q ) site which is the traditional substrate binding site; and (ii) a high affinity (Q ) site where a "permanently" bound quinone acts as a cofactor, taking two electrons from the substrate quinol and passing them one-by-one to the heme b component of the enzyme which, in turn, transfers them to the heme o /Cu active site. Whereas the residues at the Q site are well defined, the location of the Q site remains unknown. The published X-ray structure does not contain quinone, and substantial amounts of the protein are missing as well. A recent bioinformatics study by Bossis et al. [Biochem J. (2014) 461, 305-314] identified a sequence motif G EFX GWX Y as the likely Q site in the family of related quinol oxidases. In the current work, this was tested by site-directed mutagenesis. The results show that these residues are not important for catalytic function and do not define the Q substrate binding site.
[Mh] Termos MeSH primário: Citocromos/metabolismo
Proteínas de Escherichia coli/metabolismo
Escherichia coli/enzimologia
Ubiquinona/metabolismo
[Mh] Termos MeSH secundário: Sítios de Ligação
Catálise
Citocromos/química
Citocromos/genética
Escherichia coli/genética
Proteínas de Escherichia coli/química
Proteínas de Escherichia coli/genética
Modelos Moleculares
Mutagênese Sítio-Dirigida
Mutação
Oxirredução
Ligação Proteica
Conformação Proteica
Relação Estrutura-Atividade
Ubiquinona/análogos & derivados
Ubiquinona/química
Água/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Cytochromes); 0 (Escherichia coli Proteins); 0 (cytochrome bo3, E coli); 059QF0KO0R (Water); 1339-63-5 (Ubiquinone); M9NL0C577Y (ubiquinol)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170824
[Lr] Data última revisão:
170824
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170226
[St] Status:MEDLINE


  9 / 8373 MEDLINE  
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[PMID]:28219973
[Au] Autor:Goddard-Borger ED; Williams SJ
[Ad] Endereço:ACRF Chemical Biology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia.
[Ti] Título:Sulfoquinovose in the biosphere: occurrence, metabolism and functions.
[So] Source:Biochem J;474(5):827-849, 2017 Feb 20.
[Is] ISSN:1470-8728
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The sulfonated carbohydrate sulfoquinovose (SQ) is produced in quantities estimated at some 10 billion tonnes annually and is thus a major participant in the global sulfur biocycle. SQ is produced by most photosynthetic organisms and incorporated into the sulfolipid sulfoquinovosyl diacylglycerol (SQDG), as well as within some archaea for incorporation into glycoprotein N-glycans. SQDG is found mainly within the thylakoid membranes of the chloroplast, where it appears to be important for membrane structure and function and for optimal activity of photosynthetic protein complexes. SQDG metabolism within the sulfur cycle involves complex biosynthetic and catabolic processes. SQDG biosynthesis is largely conserved within plants, algae and bacteria. On the other hand, two major sulfoglycolytic pathways have been discovered for SQDG degradation, the sulfo-Embden-Meyerhof-Parnas (sulfo-EMP) and sulfo-Entner-Doudoroff (sulfo-ED) pathways, which mirror the major steps in the glycolytic EMP and ED pathways. Sulfoglycolysis produces C3-sulfonates, which undergo biomineralization to inorganic sulfur species, completing the sulfur cycle. This review discusses the discovery and structural elucidation of SQDG and archaeal N-glycans, the occurrence, distribution, and speciation of SQDG, and metabolic pathways leading to the biosynthesis of SQDG and its catabolism through sulfoglycolytic and biomineralization pathways to inorganic sulfur.
[Mh] Termos MeSH primário: Glicolipídeos/metabolismo
Metilglucosídeos/metabolismo
Complexo de Proteínas do Centro de Reação Fotossintética/fisiologia
Enxofre/metabolismo
Tilacoides/metabolismo
[Mh] Termos MeSH secundário: Archaea/metabolismo
Cianobactérias/metabolismo
Citocromos/química
Citocromos/metabolismo
Glucosiltransferases/química
Glucosiltransferases/metabolismo
Glicolipídeos/química
Lipídeos/química
Redes e Vias Metabólicas
Metilglucosídeos/química
Modelos Moleculares
Fotossíntese/fisiologia
Complexo de Proteínas do Centro de Reação Fotossintética/química
Plantas/metabolismo
Tilacoides/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Cytochromes); 0 (Glycolipids); 0 (Lipids); 0 (Methylglucosides); 0 (Photosynthetic Reaction Center Complex Proteins); 0 (sulfolipids); 0 (sulfoquinovosyl diglyceride); 3458-06-8 (sulfoquinovose); 70FD1KFU70 (Sulfur); EC 2.4.1.- (Glucosyltransferases); EC 2.4.1.121 (UDP-sulfoquinovose synthase, Chlamydomonas reinhardtii)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170614
[Lr] Data última revisão:
170614
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170222
[St] Status:MEDLINE
[do] DOI:10.1042/BCJ20160508


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[PMID]:28184354
[Au] Autor:Hijazi S; Visca P; Frangipani E
[Ad] Endereço:Department of Science, Roma Tre University Rome, Italy.
[Ti] Título:Gallium-Protoporphyrin IX Inhibits Growth by Targeting Cytochromes.
[So] Source:Front Cell Infect Microbiol;7:12, 2017.
[Is] ISSN:2235-2988
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:is a challenging pathogen due to both innate and acquired resistance to antibiotics. It is capable of causing a variety of infections, including chronic lung infection in cystic fibrosis (CF) patients. Given the importance of iron in bacterial physiology and pathogenicity, iron-uptake and metabolism have become attractive targets for the development of new antibacterial compounds. can acquire iron from a variety of sources to fulfill its nutritional requirements both in the environment and in the infected host. The adaptation of to heme iron acquisition in the CF lung makes heme utilization pathways a promising target for the development of new anti- drugs. Gallium [Ga(III)] is an iron mimetic metal which inhibits growth by interfering with iron-dependent metabolism. The Ga(III) complex of the heme precursor protoporphyrin IX (GaPPIX) showed enhanced antibacterial activity against several bacterial species, although no inhibitory effect has been reported on . Here, we demonstrate that GaPPIX is indeed capable of inhibiting the growth of clinical strains under iron-deplete conditions, as those encountered by bacteria during infection, and that GaPPIX inhibition is reversed by iron. Using PAO1 as model organism, we show that GaPPIX enters cells through both the heme-uptake systems and , primarily the PhuR receptor which plays a crucial role in adaptation to the CF lung. We also demonstrate that intracellular GaPPIX inhibits the aerobic growth of by targeting cytochromes, thus interfering with cellular respiration.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Citocromos/antagonistas & inibidores
Gálio/farmacologia
Protoporfirinas/farmacologia
Pseudomonas aeruginosa/efeitos dos fármacos
[Mh] Termos MeSH secundário: Aerobiose
Transporte de Elétrons/efeitos dos fármacos
Testes de Sensibilidade Microbiana
Pseudomonas aeruginosa/enzimologia
Pseudomonas aeruginosa/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Cytochromes); 0 (Protoporphyrins); C2K325S808 (protoporphyrin IX); CH46OC8YV4 (Gallium)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170918
[Lr] Data última revisão:
170918
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170211
[St] Status:MEDLINE
[do] DOI:10.3389/fcimb.2017.00012



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