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Pesquisa : G05.360.340.024.742 [Categoria DeCS]
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[PMID]:28468910
[Au] Autor:Dapa T; Fleurier S; Bredeche MF; Matic I
[Ad] Endereço:INSERM U1001, Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine Paris Descartes, 75014, France.
[Ti] Título:The SOS and RpoS Regulons Contribute to Bacterial Cell Robustness to Genotoxic Stress by Synergistically Regulating DNA Polymerase Pol II.
[So] Source:Genetics;206(3):1349-1360, 2017 07.
[Is] ISSN:1943-2631
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Mitomycin C (MMC) is a genotoxic agent that induces DNA cross-links, DNA alkylation, and the production of reactive oxygen species (ROS). MMC induces the SOS response and RpoS regulons in SOS-encoded functions are required for DNA repair, whereas the RpoS regulon is typically induced by metabolic stresses that slow growth. Thus, induction of the RpoS regulon by MMC may be coincidental, because DNA damage slows growth; alternatively, the RpoS regulon may be an adaptive response contributing to cell survival. In this study, we show that the RpoS regulon is primarily induced by MMC-induced ROS production. We also show that RpoS regulon induction is required for the survival of MMC-treated growing cells. The major contributor to RpoS-dependent resistance to MMC treatment is DNA polymerase Pol II, which is encoded by the gene belonging to the SOS regulon. The observation that gene expression is controlled by the two major stress response regulons that are required to maximize survival and fitness further emphasizes the key role of this DNA polymerase as an important factor in genome stability.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Dano ao DNA
Proteínas de Escherichia coli/metabolismo
Resposta SOS (Genética)
Fator sigma/metabolismo
[Mh] Termos MeSH secundário: Antibacterianos/toxicidade
Proteínas de Bactérias/genética
Escherichia coli/efeitos dos fármacos
Escherichia coli/genética
Escherichia coli/metabolismo
Proteínas de Escherichia coli/genética
Mitomicina/toxicidade
Mutagênicos/toxicidade
Espécies Reativas de Oxigênio/metabolismo
Regulon
Fator sigma/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Proteins); 0 (Escherichia coli Proteins); 0 (Mutagens); 0 (Reactive Oxygen Species); 0 (Sigma Factor); 0 (polB protein, E coli); 0 (sigma factor KatF protein, Bacteria); 50SG953SK6 (Mitomycin)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171213
[Lr] Data última revisão:
171213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE
[do] DOI:10.1534/genetics.116.199471


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[PMID]:28965817
[Au] Autor:Hubstenberger A; Courel M; Bénard M; Souquere S; Ernoult-Lange M; Chouaib R; Yi Z; Morlot JB; Munier A; Fradet M; Daunesse M; Bertrand E; Pierron G; Mozziconacci J; Kress M; Weil D
[Ad] Endereço:UPMC Univ Paris 06, Institut de Biologie Paris-Seine (IBPS), CNRS UMR 7622, F-75005 Paris, France; Université Côte d'Azur, CNRS, Inserm, iBV, Nice, France. Electronic address: ahubsten@yahoo.fr.
[Ti] Título:P-Body Purification Reveals the Condensation of Repressed mRNA Regulons.
[So] Source:Mol Cell;68(1):144-157.e5, 2017 Oct 05.
[Is] ISSN:1097-4164
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Within cells, soluble RNPs can switch states to coassemble and condense into liquid or solid bodies. Although these phase transitions have been reconstituted in vitro, for endogenous bodies the diversity of the components, the specificity of the interaction networks, and the function of the coassemblies remain to be characterized. Here, by developing a fluorescence-activated particle sorting (FAPS) method to purify cytosolic processing bodies (P-bodies) from human epithelial cells, we identified hundreds of proteins and thousands of mRNAs that structure a dense network of interactions, separating P-body from non-P-body RNPs. mRNAs segregating into P-bodies are translationally repressed, but not decayed, and this repression explains part of the poor genome-wide correlation between RNA and protein abundance. P-bodies condense thousands of mRNAs that strikingly encode regulatory processes. Thus, we uncovered how P-bodies, by condensing and segregating repressed mRNAs, provide a physical substrate for the coordinated regulation of posttranscriptional mRNA regulons.
[Mh] Termos MeSH primário: Regulação da Expressão Gênica
Proteoma/genética
RNA Mensageiro/genética
Regulon
Ribonucleoproteínas/genética
[Mh] Termos MeSH secundário: Fracionamento Celular
Citoplasma/metabolismo
Grânulos Citoplasmáticos/química
Grânulos Citoplasmáticos/metabolismo
Ontologia Genética
Células HEK293
Células HeLa
Seres Humanos
Anotação de Sequência Molecular
Transição de Fase
Biossíntese de Proteínas
Proteoma/metabolismo
Estabilidade de RNA
RNA Mensageiro/metabolismo
Ribonucleoproteínas/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Proteome); 0 (RNA, Messenger); 0 (Ribonucleoproteins)
[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:171003
[St] Status:MEDLINE


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[PMID]:28950103
[Au] Autor:Pascual J; Jacobs J; Sansores-Garcia L; Natarajan M; Zeitlinger J; Aerts S; Halder G; Hamaratoglu F
[Ad] Endereço:Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland.
[Ti] Título:Hippo Reprograms the Transcriptional Response to Ras Signaling.
[So] Source:Dev Cell;42(6):667-680.e4, 2017 Sep 25.
[Is] ISSN:1878-1551
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Hyperactivating mutations in Ras signaling are hallmarks of carcinomas. Ras signaling mediates cell fate decisions as well as proliferation during development. It is not known what dictates whether Ras signaling drives differentiation versus proliferation. Here we show that the Hippo pathway is critical for this decision. Loss of Hippo switches Ras activation from promoting cellular differentiation to aggressive cellular proliferation. Transcriptome analysis combined with genetic tests show that this excessive proliferation depends on the synergistic induction of Ras target genes. Using ChIP-nexus, we find that Hippo signaling keeps Ras targets in check by directly regulating the expression of two key downstream transcription factors of Ras signaling: the ETS-domain transcription factor Pointed and the repressor Capicua. Our results highlight how independent signaling pathways can impinge on each other at the level of transcription factors, thereby providing a safety mechanism to keep proliferation in check under normal developmental conditions.
[Mh] Termos MeSH primário: Proteínas de Drosophila/metabolismo
Drosophila melanogaster/genética
Transdução de Sinais
Transcrição Genética
Proteínas ras/metabolismo
[Mh] Termos MeSH secundário: Animais
Diferenciação Celular/genética
Proliferação Celular/genética
Drosophila melanogaster/citologia
Drosophila melanogaster/metabolismo
Regulação da Expressão Gênica no Desenvolvimento
Genes de Insetos
Modelos Biológicos
Mutação/genética
Pupa/metabolismo
Receptor do Fator de Crescimento Epidérmico/metabolismo
Regulon/genética
Análise de Sequência de RNA
Fatores de Transcrição/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Drosophila Proteins); 0 (Transcription Factors); EC 2.7.10.1 (Receptor, Epidermal Growth Factor); EC 3.6.5.2 (ras Proteins)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171030
[Lr] Data última revisão:
171030
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170927
[St] Status:MEDLINE


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[PMID]:28898293
[Au] Autor:Lin HV; Massam-Wu T; Lin CP; Wang YA; Shen YC; Lu WJ; Hsu PH; Chen YH; Borges-Walmsley MI; Walmsley AR
[Ad] Endereço:Department of Food Science, National Taiwan Ocean University, Keelung, Taiwan.
[Ti] Título:The Vibrio cholerae var regulon encodes a metallo-ß-lactamase and an antibiotic efflux pump, which are regulated by VarR, a LysR-type transcription factor.
[So] Source:PLoS One;12(9):e0184255, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The genome sequence of V. cholerae O1 Biovar Eltor strain N16961 has revealed a putative antibiotic resistance (var) regulon that is predicted to encode a transcriptional activator (VarR), which is divergently transcribed relative to the putative resistance genes for both a metallo-ß-lactamase (VarG) and an antibiotic efflux-pump (VarABCDEF). We sought to test whether these genes could confer antibiotic resistance and are organised as a regulon under the control of VarR. VarG was overexpressed and purified and shown to have ß-lactamase activity against penicillins, cephalosporins and carbapenems, having the highest activity against meropenem. The expression of VarABCDEF in the Escherichia coli (ΔacrAB) strain KAM3 conferred resistance to a range of drugs, but most significant resistance was to the macrolide spiramycin. A gel-shift analysis was used to determine if VarR bound to the promoter regions of the resistance genes. Consistent with the regulation of these resistance genes, VarR binds to three distinct intergenic regions, varRG, varGA and varBC located upstream and adjacent to varG, varA and varC, respectively. VarR can act as a repressor at the varRG promoter region; whilst this repression was relieved upon addition of ß-lactams, these did not dissociate the VarR/varRG-DNA complex, indicating that the de-repression of varR by ß-lactams is indirect. Considering that the genomic arrangement of VarR-VarG is strikingly similar to that of AmpR-AmpC system, it is possible that V. cholerae has evolved a system for resistance to the newer ß-lactams that would prove more beneficial to the bacterium in light of current selective pressures.
[Mh] Termos MeSH primário: Antibacterianos/metabolismo
Regulação Bacteriana da Expressão Gênica
Proteínas de Membrana Transportadoras/genética
Regulon
Fatores de Transcrição/metabolismo
Vibrio cholerae/genética
beta-Lactamases/genética
[Mh] Termos MeSH secundário: Transportadores de Cassetes de Ligação de ATP/genética
Transportadores de Cassetes de Ligação de ATP/metabolismo
Antibacterianos/farmacologia
Sequência de Bases
DNA Intergênico
Farmacorresistência Bacteriana
Genes Bacterianos
Hidrólise
Cinética
Testes de Sensibilidade Microbiana
Regiões Promotoras Genéticas
Ligação Proteica
Transcrição Genética
Vibrio cholerae/efeitos dos fármacos
Vibrio cholerae/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (DNA, Intergenic); 0 (Membrane Transport Proteins); 0 (Transcription Factors); EC 3.5.2.6 (beta-Lactamases)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171018
[Lr] Data última revisão:
171018
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170913
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0184255


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[PMID]:28874407
[Au] Autor:Reichlen MJ; Leistikow RL; Scobey MS; Born SEM; Voskuil MI
[Ad] Endereço:Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA.
[Ti] Título:Anaerobic Mycobacterium tuberculosis Cell Death Stems from Intracellular Acidification Mitigated by the DosR Regulon.
[So] Source:J Bacteriol;199(23), 2017 Dec 01.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:is a strict aerobe capable of prolonged survival in the absence of oxygen. We investigated the ability of anaerobic to counter challenges to internal pH homeostasis in the absence of aerobic respiration, the primary mechanism of proton efflux for aerobic bacilli. Anaerobic populations were markedly impaired for survival under a mildly acidic pH relative to standard culture conditions. An acidic environmental pH greatly increased the susceptibilities of anaerobic bacilli to the collapse of the proton motive force by protonophores, to antimicrobial compounds that target entry into the electron transport system, and to small organic acids with uncoupling activity. However, anaerobic bacilli exhibited high tolerance against these challenges at a near-neutral pH. At a slightly alkaline pH, which was near the optimum intracellular pH, the addition of protonophores even improved the long-term survival of bacilli. Although anaerobic bacilli under acidic conditions maintained 40% lower ATP levels than those of bacilli under standard culture conditions, ATP loss alone could not explain the drop in viability. Protonophores decreased ATP levels by more than 90% regardless of the extracellular pH but were bactericidal only under acidic conditions, indicating that anaerobic bacilli could survive an extreme ATP loss provided that the external pH was within viable intracellular parameters. Acidic conditions drastically decreased the anaerobic survival of a DosR mutant, while an alkaline environment improved the survival of the DosR mutant. Together, these findings indicate that intracellular acidification is a primary challenge for the survival of anaerobic and that the DosR regulon plays a critical role in sustaining internal pH homeostasis. During infection, bacilli are prevalent in environments largely devoid of oxygen, yet the factors that influence the survival of these severely growth-limited and metabolically limited bacilli remain poorly understood. We determined how anaerobic bacilli respond to fluctuations in environmental pH and observed that these bacilli were highly susceptible to stresses that promoted internal acidic stress, whereas conditions that promoted an alkaline internal pH promoted long-term survival even during severe ATP depletion. The DosR regulon, a major regulator of general hypoxic stress, played an important role in maintaining internal pH homeostasis under anaerobic conditions. Together, these findings indicate that in the absence of aerobic respiration, protection from internal acidification is crucial for long-term survival.
[Mh] Termos MeSH primário: Bactérias Anaeróbias/metabolismo
Bactérias Anaeróbias/fisiologia
Proteínas de Bactérias/metabolismo
Morte Celular/fisiologia
Mycobacterium tuberculosis/metabolismo
Mycobacterium tuberculosis/fisiologia
Regulon/fisiologia
[Mh] Termos MeSH secundário: Trifosfato de Adenosina/metabolismo
Antibacterianos/farmacologia
Bacillus/metabolismo
Bacillus/fisiologia
Respiração Celular/fisiologia
Transporte de Elétrons/fisiologia
Homeostase/fisiologia
Concentração de Íons de Hidrogênio
Mycobacterium tuberculosis/efeitos dos fármacos
Oxigênio/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Proteins); 8L70Q75FXE (Adenosine Triphosphate); S88TT14065 (Oxygen)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171119
[Lr] Data última revisão:
171119
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170907
[St] Status:MEDLINE


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[PMID]:28857325
[Au] Autor:Magaña Vergara C; Kallenberg CJL; Rogasch M; Hübner CG; Song YH
[Ad] Endereço:Institute of Physics, University of Luebeck, Ratzeburger Allee 160, Luebeck, 23562, Germany.
[Ti] Título:A versatile vector for mycobacterial protein production with a functional minimized acetamidase regulon.
[So] Source:Protein Sci;26(11):2302-2311, 2017 Nov.
[Is] ISSN:1469-896X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Recombinant protein expression is a prerequisite for diverse investigations of proteins at the molecular level. For targets from Mycobacterium tuberculosis it is favorable to use M. smegmatis as an expression host, a species from the same genus. In the respective shuttle vectors, target gene expression is controlled by the complex tetra-cistronic acetamidase regulon. As a result, the size of those vectors is large, rendering them of limited use, especially when the target proteins are expressed from multi-cistronic operons. Therefore, in the current work we present a versatile new expression vector in which the acetamidase regulon has been minimized by deleting the two genes amiD and amiS. We assessed the functional properties of the resulting vector pMyCA and compared it with those of the existing vector pMyNT that contains the full-length acetamidase regulon. We analyzed the growth features and protein expression patterns of M. smegmatis cultures transformed with both vectors. In addition, we created mCherry expression constructs to spectroscopically monitor the expression properties of both vectors. Our experiments showed that the minimized vector exhibited several advantages over the pMyNT vector. First, the overall yield of expressed protein is higher due to the higher yield of bacterial mass. Second, the heterologous expression was regulated more tightly, offering an expression tool for diverse target proteins. Third, it is suitable for large multi-protein complexes that are expressed from multi-cistronic operons. Additionally, our results propose a new understanding of the regulation mechanism of the acetamidase regulon with the potential to construct more optimized vectors in the future.
[Mh] Termos MeSH primário: Amidoidrolases/genética
Proteínas de Bactérias/genética
Regulação Bacteriana da Expressão Gênica
Vetores Genéticos/química
Mycobacterium smegmatis/genética
Mycobacterium tuberculosis/genética
Regulon
[Mh] Termos MeSH secundário: Amidoidrolases/metabolismo
Proteínas de Bactérias/metabolismo
Sequência de Bases
Deleção de Genes
Genes Reporter
Vetores Genéticos/metabolismo
Proteínas Luminescentes/genética
Proteínas Luminescentes/metabolismo
Mycobacterium smegmatis/metabolismo
Mycobacterium tuberculosis/metabolismo
Óperon
Regiões Promotoras Genéticas
Proteínas Recombinantes/biossíntese
Proteínas Recombinantes/genética
Proteínas Recombinantes/isolamento & purificação
Transformação Bacteriana
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Luminescent Proteins); 0 (Recombinant Proteins); 0 (red fluorescent protein); EC 3.5.- (Amidohydrolases); EC 3.5.1.- (acetamidase)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171103
[Lr] Data última revisão:
171103
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170901
[St] Status:MEDLINE
[do] DOI:10.1002/pro.3288


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[PMID]:28827216
[Au] Autor:Chen Q; Ng V; Warfel JM; Merkel TJ; Stibitz S
[Ad] Endereço:Division of Bacterial, Parasitic, and Allergenic Products, Center for Biologics Evaluation and Research, FDA, Silver Spring, Maryland, USA qing.chen@fda.hhs.gov.
[Ti] Título:Activation of Bvg-Repressed Genes in Bordetella pertussis by RisA Requires Cross Talk from Noncooperonic Histidine Kinase RisK.
[So] Source:J Bacteriol;199(22), 2017 Nov 15.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The two-component response regulator RisA, encoded by open reading frame BP3554 in the Tohama I genomic sequence, is a known activator of genes, a set of genes whose expression is increased under the same environmental conditions (known as modulation) that result in repression of the virulence regulon. Here we demonstrate that RisA is phosphorylated and that RisA phosphorylation is required for activation of genes. An adjacent histidine kinase gene, , is truncated by frameshift mutation in but not in or Neither deletion of ' or nor phenotypic modulation with MgSO affected levels of phosphorylated RisA (RisA∼P) in However, RisA phosphorylation did require the histidine kinase encoded by BP3223, here named RisK (cognate histidine kinase of RisA). RisK was also required for expression of the genes. This requirement could be obviated by the introduction of the phosphorylation-mimicking RisA mutant, indicating that an active conformation of RisA, but not phosphorylation , is crucial for activation. Interestingly, expression of genes is still modulated by MgSO in cells harboring the RisA mutation, suggesting that the activated RisA senses additional signals to control expression in response to environmental stimuli. In , the BvgAS two-component system activates the expression of virulence genes by binding of BvgA∼P to their promoters. Expression of the reciprocally regulated genes requires RisA and is also repressed by the Bvg-activated BvgR. RisA is an OmpR-like response regulator, but RisA phosphorylation was not expected because the gene for its presumed, cooperonic, histidine kinase is inactivated by mutation. In this study, we demonstrate phosphorylation of RisA by a noncooperonic histidine kinase. We also show that RisA phosphorylation is necessary but not sufficient for activation but, importantly, is not affected by BvgAS status. Instead, we propose that expression is controlled by BvgAS through its regulation of BvgR, a cyclic di-GMP (c-di-GMP) phosphodiesterase.
[Mh] Termos MeSH primário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Bordetella pertussis/genética
Regulação Bacteriana da Expressão Gênica
Receptores de Superfície Celular/genética
Receptores de Superfície Celular/metabolismo
Transativadores/metabolismo
[Mh] Termos MeSH secundário: Bordetella bronchiseptica/genética
Bordetella pertussis/metabolismo
Bordetella pertussis/patogenicidade
Mutação da Fase de Leitura
Genes Reguladores
Histidina Quinase/metabolismo
Sulfato de Magnésio/metabolismo
Mutação
Fosforilação
Regiões Promotoras Genéticas
Regulon
Transdução de Sinais
Transativadores/genética
Virulência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Bvg accessory factor protein, Bordetella pertussis); 0 (Receptors, Cell Surface); 0 (RisA protein, Bordetella); 0 (Trans-Activators); 0 (vrg protein, Bordetella pertussis); 7487-88-9 (Magnesium Sulfate); EC 2.7.13.1 (Histidine Kinase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171030
[Lr] Data última revisão:
171030
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170823
[St] Status:MEDLINE


  8 / 2185 MEDLINE  
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[PMID]:28765283
[Au] Autor:Ebert M; Schweyen P; Bröring M; Laass S; Härtig E; Jahn D
[Ad] Endereço:From the Institute of Microbiology, Technische Universität Braunschweig, Spielmannstrasse 7, D-38106 Braunschweig.
[Ti] Título:Heme and nitric oxide binding by the transcriptional regulator DnrF from the marine bacterium increases promoter affinity.
[So] Source:J Biol Chem;292(37):15468-15480, 2017 Sep 15.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Under oxygen-limiting conditions, the marine bacterium DFL12 generates energy via denitrification, a respiratory process in which nitric oxide (NO) is an intermediate. Accumulation of NO may cause cytotoxic effects. The response to this nitrosative (NO-triggered) stress is controlled by the Crp/Fnr-type transcriptional regulator DnrF. We analyzed the response to NO and the mechanism of NO sensing by the DnrF regulator. Using reporter gene fusions and transcriptomics, here we report that DnrF selectively repressed nitrate reductase ( ) genes, preventing further NO formation. In addition, DnrF induced the expression of the NO reductase genes ( ), which promote NO consumption. We used UV-visible and EPR spectroscopy to characterize heme binding to DnrF and subsequent NO coordination. DnrF detects NO via its bound heme cofactor. We found that the dimeric DnrF bound one molecule of heme per subunit. Purified recombinant apo-DnrF bound its target promoter sequences ( , , , and ) in electromobility shift assays, and we identified a specific palindromic DNA-binding site 5'-TTGATN ATCAA-3' in these target sequences via mutagenesis studies. Most importantly, successive addition of heme as well as heme and NO to purified recombinant apo-DnrF protein increased affinity of the holo-DnrF for its specific binding motif in the promoter. On the basis of these results, we propose a model for the DnrF-mediated NO stress response of this marine bacterium.
[Mh] Termos MeSH primário: Organismos Aquáticos/fisiologia
Proteínas de Bactérias/metabolismo
Heme/metabolismo
Nitrato Redutase/metabolismo
Óxido Nítrico/metabolismo
Regiões Promotoras Genéticas
Rhodobacteraceae/fisiologia
Transativadores/metabolismo
[Mh] Termos MeSH secundário: Apoproteínas/química
Apoproteínas/genética
Apoproteínas/metabolismo
Organismos Aquáticos/enzimologia
Organismos Aquáticos/crescimento & desenvolvimento
Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Sítios de Ligação
Dimerização
Ensaio de Desvio de Mobilidade Eletroforética
Deleção de Genes
Regulação Bacteriana da Expressão Gênica
Genes Reporter
Heme/química
Sequências Repetidas Invertidas
Cinética
Família Multigênica
Mutação
Nitrato Redutase/química
Nitrato Redutase/genética
Óxido Nítrico/química
Oxirredutases/genética
Oxirredutases/metabolismo
Proteínas Recombinantes de Fusão/química
Proteínas Recombinantes de Fusão/metabolismo
Regulon
Rhodobacteraceae/enzimologia
Rhodobacteraceae/crescimento & desenvolvimento
Estresse Fisiológico
Transativadores/química
Transativadores/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Apoproteins); 0 (Bacterial Proteins); 0 (Recombinant Fusion Proteins); 0 (Trans-Activators); 31C4KY9ESH (Nitric Oxide); 42VZT0U6YR (Heme); EC 1.- (Oxidoreductases); EC 1.7.2.5 (nitric-oxide reductase); EC 1.7.99.4 (Nitrate Reductase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170927
[Lr] Data última revisão:
170927
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170803
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.798728


  9 / 2185 MEDLINE  
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[PMID]:28760827
[Au] Autor:Quintana J; Novoa-Aponte L; Argüello JM
[Ad] Endereço:From the Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts 01609.
[Ti] Título:Copper homeostasis networks in the bacterium .
[So] Source:J Biol Chem;292(38):15691-15704, 2017 Sep 22.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacterial copper (Cu ) homeostasis enables both precise metallation of diverse cuproproteins and control of variable metal levels. To this end, protein networks mobilize Cu to cellular targets with remarkable specificity. However, the understanding of these processes is rather fragmented. Here, we use genome-wide transcriptomic analysis by RNA-Seq to characterize the response of to external 0.5 mm CuSO , a condition that did not generate pleiotropic effects. Pre-steady-state (5-min) and steady-state (2-h) Cu fluxes resulted in distinct transcriptome landscapes. Cells quickly responded to Cu stress by slowing down metabolism. This was restored once steady state was reached. Specific Cu homeostasis genes were strongly regulated in both conditions. Our system-wide analysis revealed induction of three Cu efflux systems (a P -ATPase, a porin, and a resistance-nodulation-division (RND) system) and of a putative Cu -binding periplasmic chaperone and the unusual presence of two cytoplasmic CopZ proteins. Both CopZ chaperones could bind Cu with high affinity. Importantly, novel transmembrane transporters probably mediating Cu influx were among those largely repressed upon Cu stress. Compartmental Cu levels appear independently controlled; the cytoplasmic Cu sensor CueR controls cytoplasmic chaperones and plasma membrane transporters, whereas CopR/S responds to periplasmic Cu Analysis of Δ and Δ mutant strains revealed a CopR regulon composed of genes involved in periplasmic Cu homeostasis and its putative DNA recognition sequence. In conclusion, our study establishes a system-wide model of a network of sensors/regulators, soluble chaperones, and influx/efflux transporters that control the Cu levels in compartments.
[Mh] Termos MeSH primário: Cobre/metabolismo
Homeostase
Pseudomonas aeruginosa/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Transporte Biológico/efeitos dos fármacos
Membrana Celular/efeitos dos fármacos
Membrana Celular/metabolismo
Proliferação Celular/efeitos dos fármacos
Sulfato de Cobre/farmacologia
Relação Dose-Resposta a Droga
Perfilação da Expressão Gênica
Genômica
Homeostase/efeitos dos fármacos
Modelos Moleculares
Conformação Proteica
Pseudomonas aeruginosa/citologia
Pseudomonas aeruginosa/efeitos dos fármacos
Pseudomonas aeruginosa/genética
Regulon/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 789U1901C5 (Copper); LRX7AJ16DT (Copper Sulfate)
[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:170802
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.804492


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[PMID]:28739675
[Au] Autor:Gao X; Liu Y; Liu H; Yang Z; Liu Q; Zhang Y; Wang Q
[Ad] Endereço:State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China.
[Ti] Título:Identification of the Regulon of AphB and Its Essential Roles in LuxR and Exotoxin Asp Expression in the Pathogen Vibrio alginolyticus.
[So] Source:J Bacteriol;199(20), 2017 Oct 15.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In species, AphB is essential to activate virulence cascades by sensing low-pH and anaerobiosis signals; however, its regulon remains largely unknown. Here, AphB is found to be a key virulence regulator in , a pathogen for marine animals and humans. Chromatin immunoprecipitation followed by high-throughput DNA sequencing (ChIP-seq) enabled the detection of 20 loci in the genome that contained AphB-binding peaks. An AphB-specific binding consensus was confirmed by electrophoretic mobility shift assays (EMSAs), and the regulation of genes flanking such binding sites was demonstrated using quantitative real-time PCR analysis. AphB binds directly to its own promoter and positively controls its own expression in later growth stages. AphB also activates the expression of the exotoxin Asp by binding directly to the promoter regions of and the master quorum-sensing (QS) regulator DNase I footprinting analysis uncovered distinct AphB-binding sites (BBS) in these promoters. Furthermore, a BBS in the promoter region overlaps that of LuxR-binding site I, which mediates the positive control of promoter activity by AphB. This study provides new insights into the AphB regulon and reveals the mechanisms underlying AphB regulation of physiological adaptation and QS-controlled virulence in In this work, AphB is determined to play essential roles in the expression of genes associated with QS, physiology, and virulence in , a pathogen for marine animals and humans. AphB was found to bind directly to 20 genes and control their expression by a 17-bp consensus binding sequence. Among the 20 genes, the gene itself was identified to be positively autoregulated, and AphB also positively controlled and expression. Taken together, these findings improve our understanding of the roles of AphB in controlling physiological adaptation and QS-controlled virulence gene expression.
[Mh] Termos MeSH primário: Proteínas de Bactérias/biossíntese
Proteínas de Bactérias/metabolismo
Exotoxinas/biossíntese
Regulação Bacteriana da Expressão Gênica
Regulon
Proteínas Repressoras/biossíntese
Transativadores/biossíntese
Transativadores/metabolismo
Vibrio alginolyticus/genética
[Mh] Termos MeSH secundário: Sítios de Ligação
Imunoprecipitação da Cromatina
Pegada de DNA
DNA Bacteriano/metabolismo
Ensaio de Desvio de Mobilidade Eletroforética
Ligação Proteica
Reação em Cadeia da Polimerase em Tempo Real
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (AphB protein, Vibrio alginolyticus); 0 (Bacterial Proteins); 0 (DNA, Bacterial); 0 (Exotoxins); 0 (Repressor Proteins); 0 (Trans-Activators); 115038-68-1 (LuxR autoinducer binding proteins); EC 3.4.- (Asp exotoxin, Vibrio alginolyticus)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171015
[Lr] Data última revisão:
171015
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170726
[St] Status:MEDLINE



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