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Referências encontradas : 686 [refinar]
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[PMID]:28591599
[Au] Autor:Chow E; Skolnick J
[Ad] Endereço:School of Computational Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia. Electronic address: echow@cc.gatech.edu.
[Ti] Título:DNA Internal Motion Likely Accelerates Protein Target Search in a Packed Nucleoid.
[So] Source:Biophys J;112(11):2261-2270, 2017 Jun 06.
[Is] ISSN:1542-0086
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Transcription factors must diffuse through densely packed and coiled DNA to find their binding sites. Using a coarse-grained model of DNA and lac repressor (LacI) in the Escherichia coli nucleoid, simulations were performed to examine how LacI diffuses in such a space. Despite the canonical picture of LacI diffusing rather freely, in reality the DNA is densely packed, is not rigid but highly mobile, and the dynamics of DNA dictates to a great extent the LacI motion. A possibly better picture of unbound LacI motion is that of gated diffusion, where DNA confines LacI in a cage, but LacI can move between cages when hindering DNA strands move out of the way. Three-dimensional diffusion constants for unbound LacI computed from simulations closely match those for unbound LacI in vivo reported in the literature. The internal motions of DNA appear to be governed by strong internal forces arising from being crowded into the small space of the nucleoid. A consequence of the DNA internal motion is that protein target search may be accelerated.
[Mh] Termos MeSH primário: DNA Bacteriano
Proteínas de Escherichia coli/metabolismo
Repressores Lac/metabolismo
Movimento (Física)
[Mh] Termos MeSH secundário: Simulação por Computador
DNA Bacteriano/química
Difusão
Escherichia coli
Proteínas de Escherichia coli/química
Hidrodinâmica
Repressores Lac/química
Modelos Genéticos
Modelos Moleculares
Conformação de Ácido Nucleico
Eletricidade Estática
Temperatura Ambiente
Viscosidade
Água/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; VIDEO-AUDIO MEDIA
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Escherichia coli Proteins); 0 (Lac Repressors); 059QF0KO0R (Water)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170814
[Lr] Data última revisão:
170814
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170608
[St] Status:MEDLINE


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[PMID]:28445507
[Au] Autor:Zygiel EM; Noren KA; Adamkiewicz MA; Aprile RJ; Bowditch HK; Carroll CL; Cerezo MAS; Dagher AM; Hebert CR; Hebert LE; Mahame GM; Milne SC; Silvestri KM; Sutherland SE; Sylvia AM; Taveira CN; VanValkenburgh DJ; Noren CJ; Hall MF
[Ad] Endereço:Department of Chemistry, Stonehill College, Easton, Massachusetts, United States of America.
[Ti] Título:Various mutations compensate for a deleterious lacZα insert in the replication enhancer of M13 bacteriophage.
[So] Source:PLoS One;12(4):e0176421, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:M13 and other members of the Ff class of filamentous bacteriophages have been extensively employed in myriad applications. The Ph.D. series of phage-displayed peptide libraries were constructed from the M13-based vector M13KE. As a direct descendent of M13mp19, M13KE contains the lacZα insert in the intergenic region between genes IV and II, where it interrupts the replication enhancer of the (+) strand origin. Phage carrying this 816-nucleotide insert are viable, but propagate in E. coli at a reduced rate compared to wild-type M13 phage, presumably due to a replication defect caused by the insert. We have previously reported thirteen compensatory mutations in the 5'-untranslated region of gene II, which encodes the replication initiator protein gIIp. Here we report several additional mutations in M13KE that restore a wild-type propagation rate. Several clones from constrained-loop variable peptide libraries were found to have ejected the majority of lacZα gene in order to reconstruct the replication enhancer, albeit with a small scar. In addition, new point mutations in the gene II 5'-untranslated region or the gene IV coding sequence have been spontaneously observed or synthetically engineered. Through phage propagation assays, we demonstrate that all these genetic modifications compensate for the replication defect in M13KE and restore the wild-type propagation rate. We discuss the mechanisms by which the insertion and ejection of the lacZα gene, as well as the mutations in the regulatory region of gene II, influence the efficiency of replication initiation at the (+) strand origin. We also examine the presence and relevance of fast-propagating mutants in phage-displayed peptide libraries.
[Mh] Termos MeSH primário: Bacteriófago M13/genética
DNA Viral/metabolismo
Repressores Lac/genética
[Mh] Termos MeSH secundário: Regiões 5' não Traduzidas
Sequência de Bases
Clonagem Molecular
DNA Viral/genética
Elementos Facilitadores Genéticos
Escherichia coli/virologia
Genoma Viral
Repressores Lac/metabolismo
Mutagênese Sítio-Dirigida
Conformação de Ácido Nucleico
Biblioteca de Peptídeos
Replicação Viral/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (5' Untranslated Regions); 0 (DNA, Viral); 0 (Lac Repressors); 0 (Peptide Library)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170907
[Lr] Data última revisão:
170907
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170427
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0176421


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[PMID]:28402875
[Au] Autor:Garza de Leon F; Sellars L; Stracy M; Busby SJ; Kapanidis AN
[Ad] Endereço:Gene Machines Group, Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, United Kingdom.
[Ti] Título:Tracking Low-Copy Transcription Factors in Living Bacteria: The Case of the lac Repressor.
[So] Source:Biophys J;112(7):1316-1327, 2017 Apr 11.
[Is] ISSN:1542-0086
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Transcription factors control the expression of genes by binding to specific sites in DNA and repressing or activating transcription in response to stimuli. The lac repressor (LacI) is a well characterized transcription factor that regulates the ability of bacterial cells to uptake and metabolize lactose. Here, we study the intracellular mobility and spatial distribution of LacI in live bacteria using photoactivated localization microscopy combined with single-particle tracking. Since we track single LacI molecules in live cells by stochastically photoactivating and observing fluorescent proteins individually, there are no limitations on the copy number of the protein under study; as a result, we were able to study the behavior of LacI in bacterial strains containing the natural copy numbers (∼40 monomers), as well as in strains with much higher copy numbers due to LacI overexpression. Our results allowed us to determine the relative abundance of specific, near-specific, and non-specific DNA binding modes of LacI in vivo, showing that all these modes are operational inside living cells. Further, we examined the spatial distribution of LacI in live cells, confirming its specific binding to lac operator regions on the chromosome; we also showed that mobile LacI molecules explore the bacterial nucleoid in a way similar to exploration by other DNA-binding proteins. Our work also provides an example of applying tracking photoactivated localization microscopy to studies of low-copy-number proteins in living bacteria.
[Mh] Termos MeSH primário: Escherichia coli/metabolismo
Dosagem de Genes
Repressores Lac/metabolismo
Viabilidade Microbiana
Fatores de Transcrição/metabolismo
[Mh] Termos MeSH secundário: Rastreamento de Células
Cromossomos Bacterianos/metabolismo
Difusão
Fluorescência
Loci Gênicos
Microscopia
Proteínas Recombinantes de Fusão/metabolismo
Frações Subcelulares/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lac Repressors); 0 (Recombinant Fusion Proteins); 0 (Transcription Factors)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170424
[Lr] Data última revisão:
170424
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170414
[St] Status:MEDLINE


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[PMID]:28295806
[Au] Autor:Vörös Z; Yan Y; Kovari DT; Finzi L; Dunlap D
[Ad] Endereço:Department of Physics, Emory University, Atlanta, Georgia, 30322.
[Ti] Título:Proteins mediating DNA loops effectively block transcription.
[So] Source:Protein Sci;26(7):1427-1438, 2017 Jul.
[Is] ISSN:1469-896X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Loops are ubiquitous topological elements formed when proteins simultaneously bind to two noncontiguous DNA sites. While a loop-mediating protein may regulate initiation at a promoter, the presence of the protein at the other site may be an obstacle for RNA polymerases (RNAP) transcribing a different gene. To test whether a DNA loop alters the extent to which a protein blocks transcription, the lac repressor (LacI) was used. The outcome of in vitro transcription along templates containing two LacI operators separated by 400 bp in the presence of LacI concentrations that produced both looped and unlooped molecules was visualized with scanning force microscopy (SFM). An analysis of transcription elongation complexes, moving for 60 s at an average of 10 nt/s on unlooped DNA templates, revealed that they more often surpassed LacI bound to the lower affinity O2 operator than to the highest affinity Os operator. However, this difference was abrogated in looped DNA molecules where LacI became a strong roadblock independently of the affinity of the operator. Recordings of transcription elongation complexes, using magnetic tweezers, confirmed that they halted for several minutes upon encountering a LacI bound to a single operator. The average pause lifetime is compatible with RNAP waiting for LacI dissociation, however, the LacI open conformation visualized in the SFM images also suggests that LacI could straddle RNAP to let it pass. Independently of the mechanism by which RNAP bypasses the LacI roadblock, the data indicate that an obstacle with looped topology more effectively interferes with transcription.
[Mh] Termos MeSH primário: DNA Bacteriano/química
RNA Polimerases Dirigidas por DNA/química
Proteínas de Escherichia coli/química
Escherichia coli/química
Óperon Lac
Repressores Lac/química
Conformação de Ácido Nucleico
Transcrição Genética
[Mh] Termos MeSH secundário: DNA Bacteriano/metabolismo
RNA Polimerases Dirigidas por DNA/metabolismo
Escherichia coli/metabolismo
Proteínas de Escherichia coli/metabolismo
Repressores Lac/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Escherichia coli Proteins); 0 (Lac Repressors); 0 (LacI protein, E coli); EC 2.7.7.6 (DNA-Directed RNA Polymerases)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170807
[Lr] Data última revisão:
170807
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170316
[St] Status:MEDLINE
[do] DOI:10.1002/pro.3156


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[PMID]:28257493
[Au] Autor:Gebhardt MJ; Jacobson RK; Shuman HA
[Ad] Endereço:Department of Microbiology, University of Chicago, Chicago, Illinois, United States of America.
[Ti] Título:Seeing red; the development of pON.mCherry, a broad-host range constitutive expression plasmid for Gram-negative bacteria.
[So] Source:PLoS One;12(3):e0173116, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The development of plasmid-mediated gene expression control in bacteria revolutionized the field of bacteriology. Many of these expression control systems rely on the addition of small molecules, generally metabolites or non-metabolized analogs thereof, to the growth medium to induce expression of the genes of interest. The paradigmatic example of an expression control system is the lac system from Escherichia coli, which typically relies on the Ptac promoter and the Lac repressor, LacI. In many cases, however, constitutive gene expression is desired, and other experimental approaches require the coordinated control of multiple genes. While multiple systems have been developed for use in E. coli and its close relatives, the utility and/or functionality of these tools does not always translate to other species. For example, for the Gram-negative pathogen, Legionella pneumophila, a causative agent of Legionnaires' Disease, the aforementioned Ptac system represents the only well-established expression control system. In order to enhance the tools available to study bacterial gene expression in L. pneumophila, we developed a plasmid, pON.mCherry, which confers constitutive gene expression from a mutagenized LacI binding site. We demonstrate that pON.mCherry neither interferes with other plasmids harboring an intact LacI-Ptac expression system nor alters the growth of Legionella species during intracellular growth. Furthermore, the broad-host range plasmid backbone of pON.mCherry allows constitutive gene expression in a wide variety of Gram-negative bacterial species, making pON.mCherry a useful tool for the greater research community.
[Mh] Termos MeSH primário: Escherichia coli/genética
Regulação Bacteriana da Expressão Gênica
Legionella pneumophila/genética
Proteínas Luminescentes/genética
Plasmídeos/química
[Mh] Termos MeSH secundário: Escherichia coli/metabolismo
Escherichia coli/ultraestrutura
Engenharia Genética
Repressores Lac/genética
Repressores Lac/metabolismo
Legionella pneumophila/metabolismo
Legionella pneumophila/ultraestrutura
Proteínas Luminescentes/metabolismo
Biologia Molecular/métodos
Mutação
Plasmídeos/metabolismo
Regiões Promotoras Genéticas
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lac Repressors); 0 (Luminescent Proteins); 0 (red fluorescent protein)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170828
[Lr] Data última revisão:
170828
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170304
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0173116


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[PMID]:28160597
[Au] Autor:Hao N; Sneppen K; Shearwin KE; Dodd IB
[Ad] Endereço:Department of Molecular and Cellular Biology, University of Adelaide, North Terrace, Adelaide SA 5005, Australia.
[Ti] Título:Efficient chromosomal-scale DNA looping in Escherichia coli using multiple DNA-looping elements.
[So] Source:Nucleic Acids Res;45(9):5074-5085, 2017 May 19.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Genes are frequently regulated by interactions between proteins that bind to the DNA near the gene and proteins that bind to DNA sites located far away, with the intervening DNA looped out. But it is not understood how efficient looping can occur when the sites are very far apart. We develop a simple theoretical framework that relates looping efficiency to the energetic cost and benefit of looping, allowing prediction of the efficiency of single or multiple nested loops at different distances. Measurements of absolute loop efficiencies for Lac repressor and λ CI using gene expression reporters in Escherichia coli cells show that, as predicted by the model, long-range DNA looping between a pair of sites can be strongly enhanced by the use of nested DNA loops or by the use of additional protein-binding sequences. A combination of these approaches was able to generate efficient DNA looping at a 200 kb distance.
[Mh] Termos MeSH primário: DNA Bacteriano
Escherichia coli/genética
Conformação de Ácido Nucleico
[Mh] Termos MeSH secundário: Cromossomos Bacterianos
DNA Bacteriano/química
DNA Bacteriano/metabolismo
Proteínas de Ligação a DNA/metabolismo
Escherichia coli/química
Escherichia coli/metabolismo
Proteínas de Escherichia coli/metabolismo
Repressores Lac/metabolismo
Modelos Genéticos
Ligação Proteica
Proteínas Repressoras/metabolismo
Proteínas Virais/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (DNA-Binding Proteins); 0 (Escherichia coli Proteins); 0 (Lac Repressors); 0 (LacI protein, E coli); 0 (Repressor Proteins); 0 (Viral Proteins); 0 (repressor protein C1, bacteriophage)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170829
[Lr] Data última revisão:
170829
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170205
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkx069


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[PMID]:27836746
[Au] Autor:Higa M; Kushiyama T; Kurashige S; Kohmon D; Enokitani K; Iwahori S; Sugimoto N; Yoshida K; Fujita M
[Ad] Endereço:Department of Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
[Ti] Título:TRF2 recruits ORC through TRFH domain dimerization.
[So] Source:Biochim Biophys Acta;1864(1):191-201, 2017 01.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Telomeres are specialized chromatin structures that prevent the degradation and instability of the ends of linear chromosomes. While telomerase maintains long stretches of the telomeric repeat, the majority of telomeric DNA is duplicated by conventional DNA replication. A fundamental step in eukaryotic DNA replication involves chromatin binding of the origin recognition complex (ORC). In human cells, telomeric repeat binding factor 2 (TRF2) is thought to play a role in the recruitment of ORC onto telomeres. To better understand the mechanism of TRF2-mediated ORC recruitment, we utilized a lacO-LacI protein tethering system in U2OS cells and found that ectopically targeted TRF2, but not TRF1, can recruit ORC onto the lacO array. We further found that the TRF homology (TRFH) dimerization domain of TRF2, but not its mutant defective in dimerization, is sufficient for ORC and minichromosome maintenance (MCM) recruitment. Mutations impairing the dimerization also compromised ORC recruitment by full-length TRF2. Similar results were obtained using immunoprecipitation and GST pull-down assays. Together, these results suggest that dimerized TRF2 recruits ORC and stimulates pre-replication complex (pre-RC) formation at telomeres through the TRFH domain.
[Mh] Termos MeSH primário: Cromatina/química
Proteínas de Manutenção de Minicromossomo/metabolismo
Complexo de Reconhecimento de Origem/metabolismo
Telômero/metabolismo
Proteína 2 de Ligação a Repetições Teloméricas/metabolismo
[Mh] Termos MeSH secundário: Linhagem Celular Tumoral
Cromatina/metabolismo
Replicação do DNA
Proteínas de Escherichia coli/genética
Proteínas de Escherichia coli/metabolismo
Expressão Gênica
Células HEK293
Células HeLa
Seres Humanos
Repressores Lac/genética
Repressores Lac/metabolismo
Proteínas de Manutenção de Minicromossomo/genética
Mutação
Complexo de Reconhecimento de Origem/genética
Osteoblastos/citologia
Osteoblastos/metabolismo
Domínios Proteicos
Multimerização Proteica
Transdução de Sinais
Telômero/ultraestrutura
Proteína 1 de Ligação a Repetições Teloméricas/genética
Proteína 1 de Ligação a Repetições Teloméricas/metabolismo
Proteína 2 de Ligação a Repetições Teloméricas/química
Proteína 2 de Ligação a Repetições Teloméricas/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Chromatin); 0 (Escherichia coli Proteins); 0 (Lac Repressors); 0 (LacI protein, E coli); 0 (Origin Recognition Complex); 0 (TERF2 protein, human); 0 (Telomeric Repeat Binding Protein 1); 0 (Telomeric Repeat Binding Protein 2); EC 3.6.4.12 (Minichromosome Maintenance Proteins)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171004
[Lr] Data última revisão:
171004
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161113
[St] Status:MEDLINE


  8 / 686 MEDLINE  
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[PMID]:27598336
[Au] Autor:Richards DH; Meyer S; Wilson CJ
[Ad] Endereço:Department of Molecular Biophysics & Biochemistry, Yale University , New Haven, Connecticut 06520, United States.
[Ti] Título:Fourteen Ways to Reroute Cooperative Communication in the Lactose Repressor: Engineering Regulatory Proteins with Alternate Repressive Functions.
[So] Source:ACS Synth Biol;6(1):6-12, 2017 01 20.
[Is] ISSN:2161-5063
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The lactose repressor (LacI) is a classic genetic switch that has been used as a fundamental component in a host of synthetic genetic networks. To expand the function of LacI for use in the development of novel networks and other biotechnological applications, we engineered alternate communication in the LacI scaffold via laboratory evolution. Here we produced 14 new regulatory elements based on the LacI topology that are responsive to isopropyl ß-d-1-thiogalactopyranoside (IPTG) with variation in repression strengths and ligand sensitivities-on solid media. The new variants exhibit repressive as well as antilac (i.e., inverse-repression + IPTG) functions and variations in the control of gene output upon exposure to different concentrations of IPTG. In addition, examination of this collection of variants in solution results in the controlled output of a canonical florescent reporter, demonstrating the utility of this collection of new regulatory proteins under standard conditions.
[Mh] Termos MeSH primário: Repressores Lac/genética
Engenharia de Proteínas
[Mh] Termos MeSH secundário: Regulação Alostérica/efeitos dos fármacos
Escherichia coli/genética
Escherichia coli/metabolismo
Expressão Gênica/efeitos dos fármacos
Genes Reporter
Isopropiltiogalactosídeo/farmacologia
Repressores Lac/química
Repressores Lac/metabolismo
Mutação Puntual
Reação em Cadeia da Polimerase
Domínios Proteicos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Lac Repressors); 367-93-1 (Isopropyl Thiogalactoside)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170216
[Lr] Data última revisão:
170216
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160907
[St] Status:MEDLINE
[do] DOI:10.1021/acssynbio.6b00048


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[PMID]:27425413
[Au] Autor:Lee JW; Gyorgy A; Cameron DE; Pyenson N; Choi KR; Way JC; Silver PA; Del Vecchio D; Collins JJ
[Ad] Endereço:Institute for Medical Engineering & Science, Department of Biological Engineering, and Synthetic Biology Center, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA.
[Ti] Título:Creating Single-Copy Genetic Circuits.
[So] Source:Mol Cell;63(2):329-336, 2016 Jul 21.
[Is] ISSN:1097-4164
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Synthetic biology is increasingly used to develop sophisticated living devices for basic and applied research. Many of these genetic devices are engineered using multi-copy plasmids, but as the field progresses from proof-of-principle demonstrations to practical applications, it is important to develop single-copy synthetic modules that minimize consumption of cellular resources and can be stably maintained as genomic integrants. Here we use empirical design, mathematical modeling, and iterative construction and testing to build single-copy, bistable toggle switches with improved performance and reduced metabolic load that can be stably integrated into the host genome. Deterministic and stochastic models led us to focus on basal transcription to optimize circuit performance and helped to explain the resulting circuit robustness across a large range of component expression levels. The design parameters developed here provide important guidance for future efforts to convert functional multi-copy gene circuits into optimized single-copy circuits for practical, real-world use.
[Mh] Termos MeSH primário: Escherichia coli/genética
Dosagem de Genes
Engenharia Genética/métodos
Genoma Bacteriano
Modelos Genéticos
Plasmídeos/genética
Biologia Sintética/métodos
Transcrição Genética
[Mh] Termos MeSH secundário: Metabolismo Energético
Escherichia coli/crescimento & desenvolvimento
Escherichia coli/metabolismo
Proteínas de Escherichia coli/genética
Proteínas de Escherichia coli/metabolismo
Regulação Bacteriana da Expressão Gênica
Repressores Lac/genética
Repressores Lac/metabolismo
Proteínas Luminescentes/genética
Proteínas Luminescentes/metabolismo
Plasmídeos/metabolismo
Processos Estocásticos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Escherichia coli Proteins); 0 (Lac Repressors); 0 (LacI protein, E coli); 0 (Luminescent Proteins); 0 (TetR(B) protein, E coli)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170921
[Lr] Data última revisão:
170921
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160719
[St] Status:MEDLINE


  10 / 686 MEDLINE  
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[PMID]:27193534
[Au] Autor:Wollman AJ; Syeda AH; McGlynn P; Leake MC
[Ad] Endereço:Department of Physics and Biology, Biological Physical Sciences Institute, University of York, York, YO10 5DD, UK. adam.wollman@york.ac.uk.
[Ti] Título:Single-Molecule Observation of DNA Replication Repair Pathways in E. coli.
[So] Source:Adv Exp Med Biol;915:5-16, 2016.
[Is] ISSN:0065-2598
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The method of action of many antibiotics is to interfere with DNA replication-quinolones trap DNA gyrase and topoisomerase proteins onto DNA while metronidazole causes single- and double-stranded breaks in DNA. To understand how bacteria respond to these drugs, it is important to understand the repair processes utilised when DNA replication is blocked. We have used tandem lac operators inserted into the chromosome bound by fluorescently labelled lac repressors as a model protein block to replication in E. coli. We have used dual-colour, alternating-laser, single-molecule narrowfield microscopy to quantify the amount of operator at the block and simultaneously image fluorescently labelled DNA polymerase. We anticipate use of this system as a quantitative platform to study replication stalling and repair proteins.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Replicação do DNA/efeitos dos fármacos
DNA Bacteriano/efeitos dos fármacos
Infecções por Escherichia coli/tratamento farmacológico
Escherichia coli/efeitos dos fármacos
Microscopia de Fluorescência
Imagem Molecular/métodos
[Mh] Termos MeSH secundário: Animais
DNA Bacteriano/biossíntese
DNA Bacteriano/genética
DNA Polimerase Dirigida por DNA/genética
DNA Polimerase Dirigida por DNA/metabolismo
Escherichia coli/genética
Escherichia coli/crescimento & desenvolvimento
Escherichia coli/metabolismo
Infecções por Escherichia coli/imunologia
Infecções por Escherichia coli/microbiologia
Proteínas de Escherichia coli/genética
Proteínas de Escherichia coli/metabolismo
Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos
Genes Reporter
Seres Humanos
Processamento de Imagem Assistida por Computador
Óperon Lac
Repressores Lac/genética
Repressores Lac/metabolismo
Proteínas Luminescentes/genética
Proteínas Luminescentes/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (DNA, Bacterial); 0 (Escherichia coli Proteins); 0 (Lac Repressors); 0 (LacI protein, E coli); 0 (Luminescent Proteins); EC 2.7.7.7 (DNA-Directed DNA Polymerase)
[Em] Mês de entrada:1609
[Cu] Atualização por classe:161109
[Lr] Data última revisão:
161109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160520
[St] Status:MEDLINE
[do] DOI:10.1007/978-3-319-32189-9_2



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