Base de dados : MEDLINE
Pesquisa : células and procarióticas [Palavras]
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  1 / 2543 MEDLINE  
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[PMID]:29253874
[Au] Autor:Martynov A; Severinov K; Ispolatov I
[Ad] Endereço:Center for Data-Intensive Biomedicine and Biotechnology, Skolkovo Institute of Science and Technology, Moscow, Russia.
[Ti] Título:Optimal number of spacers in CRISPR arrays.
[So] Source:PLoS Comput Biol;13(12):e1005891, 2017 12.
[Is] ISSN:1553-7358
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Prokaryotic organisms survive under constant pressure of viruses. CRISPR-Cas system provides its prokaryotic host with an adaptive immune defense against viruses that have been previously encountered. It consists of two components: Cas-proteins that cleave the foreign DNA and CRISPR array that suits as a virus recognition key. CRISPR array consists of a series of spacers, short pieces of DNA that originate from and match the corresponding parts of viral DNA called protospacers. Here we estimate the number of spacers in a CRISPR array of a prokaryotic cell which maximizes its protection against a viral attack. The optimality follows from a competition between two trends: too few distinct spacers make host vulnerable to an attack by a virus with mutated corresponding protospacers, while an excessive variety of spacers dilutes the number of the CRISPR complexes armed with the most recent and thus most useful spacers. We first evaluate the optimal number of spacers in a simple scenario of an infection by a single viral species and later consider a more general case of multiple viral species. We find that depending on such parameters as the concentration of CRISPR-Cas interference complexes and its preference to arm with more recently acquired spacers, the rate of viral mutation, and the number of viral species, the predicted optimal number of spacers lies within a range that agrees with experimentally-observed values.
[Mh] Termos MeSH primário: Sistemas CRISPR-Cas
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética
[Mh] Termos MeSH secundário: Imunidade Adaptativa/genética
Archaea/genética
Archaea/imunologia
Archaea/virologia
Bactérias/genética
Bactérias/imunologia
Bactérias/virologia
Biologia Computacional
Simulação por Computador
DNA Intergênico/genética
DNA Viral/genética
Modelos Genéticos
Modelos Imunológicos
Mutação
Células Procarióticas/imunologia
Células Procarióticas/virologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Intergenic); 0 (DNA, Viral)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180123
[Lr] Data última revisão:
180123
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pcbi.1005891


  2 / 2543 MEDLINE  
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[PMID]:29292687
[Au] Autor:Chun J; Oren A; Ventosa A; Christensen H; Arahal DR; da Costa MS; Rooney AP; Yi H; Xu XW; De Meyer S; Trujillo ME
[Ad] Endereço:1​Department of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 08826, Republic of Korea.
[Ti] Título:Proposed minimal standards for the use of genome data for the taxonomy of prokaryotes.
[So] Source:Int J Syst Evol Microbiol;68(1):461-466, 2018 Jan.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Advancement of DNA sequencing technology allows the routine use of genome sequences in the various fields of microbiology. The information held in genome sequences proved to provide objective and reliable means in the taxonomy of prokaryotes. Here, we describe the minimal standards for the quality of genome sequences and how they can be applied for taxonomic purposes.
[Mh] Termos MeSH primário: Genômica/normas
Filogenia
Células Procarióticas/classificação
Análise de Sequência de DNA/normas
[Mh] Termos MeSH secundário: Terminologia como Assunto
[Pt] Tipo de publicação:JOURNAL ARTICLE
[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:180103
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.002516


  3 / 2543 MEDLINE  
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[PMID]:28886378
[Au] Autor:Umen J; Goodenough U; Heitman J
[Ad] Endereço:Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA.
[Ti] Título:Eukaryotic Sexual Reproduction Evoked "with a Little Help from My Friends".
[So] Source:Cell;170(6):1059-1061, 2017 09 07.
[Is] ISSN:1097-4172
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacteria and eukaryotes interact in many ways-from the microbiome that educates the mammalian immune system and enhances nutrition to relationships that are commensal, symbiotic, or parasitic. Now in an unexpected twist, King and colleagues have expanded the repertoire of prokaryotic influence over eukaryotic physiology to include mating.
[Mh] Termos MeSH primário: Eucariotos
Células Eucarióticas
Sistema Imunitário/fisiologia
[Mh] Termos MeSH secundário: Animais
Bactérias
Mamíferos
Células Procarióticas
Reprodução
[Pt] Tipo de publicação:JOURNAL ARTICLE; COMMENT
[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:170909
[St] Status:MEDLINE


  4 / 2543 MEDLINE  
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[PMID]:28750056
[Au] Autor:Sun Y; Li Y; Wu Y; Xiong L; Li C; Wang C; Li D; Lan J; Zhang Z; Jing B; Gu X; Xie Y; Lai W; Peng X; Yang G
[Ad] Endereço:Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.
[Ti] Título:Fatty-binding protein and galectin of Baylisascaris schroederi: Prokaryotic expression and preliminary evaluation of serodiagnostic potential.
[So] Source:PLoS One;12(7):e0182094, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Baylisascaris schroederi is a common parasite of captive giant pandas. The diagnosis of this ascariasis is normally carried out by a sedimentation-floatation method or PCR to detect eggs in feces, but neither method is suitable for early diagnosis. Fatty acid-binding protein (FABP) and galectin (GAL) exist in various animals and participate in important biology of parasites. Because of their good immunogenicity, they are seen as potential antigens for the diagnosis of parasitic diseases. In this study, we cloned and expressed recombinant FABP and GAL from B. schroederi (rBs-FABP and rBs-GAL) and developed indirect enzyme-linked immunosorbent assays (ELISAs) to evaluate their potential for diagnosing ascariasis in giant pandas. Immunolocalization showed that Bs-FABP and Bs-GAL were widely distributed in adult worms. The ELISA based on rBs-FABP showed sensitivity of 95.8% (23/24) and specificity of 100% (12/12), and that based on rBs-GAL had sensitivity of 91.7% (22/24) and specificity of 100% (12/12).
[Mh] Termos MeSH primário: Ascaridoidea/metabolismo
Proteínas de Ligação a Ácido Graxo/metabolismo
Galectinas/metabolismo
Células Procarióticas/metabolismo
Testes Sorológicos/métodos
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
Western Blotting
Clonagem Molecular
Ensaio de Imunoadsorção Enzimática
Proteínas de Ligação a Ácido Graxo/química
Feminino
Galectinas/química
Immunoblotting
Masculino
Camundongos Endogâmicos ICR
Filogenia
Coelhos
Proteínas Recombinantes/isolamento & purificação
Proteínas Recombinantes/metabolismo
Sensibilidade e Especificidade
Alinhamento de Sequência
Análise de Sequência de DNA
Ursidae/parasitologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fatty Acid-Binding Proteins); 0 (Galectins); 0 (Recombinant 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:170728
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0182094


  5 / 2543 MEDLINE  
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[PMID]:28639931
[Au] Autor:Lee I; Chalita M; Ha SM; Na SI; Yoon SH; Chun J
[Ad] Endereço:1​School of Biological Sciences & Institute of Molecular Biology & Genetics, Seoul National University, Seoul 151-742, Republic of Korea.
[Ti] Título:ContEst16S: an algorithm that identifies contaminated prokaryotic genomes using 16S RNA gene sequences.
[So] Source:Int J Syst Evol Microbiol;67(6):2053-2057, 2017 Jun.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Thanks to the recent advancement of DNA sequencing technology, the cost and time of prokaryotic genome sequencing have been dramatically decreased. It has repeatedly been reported that genome sequencing using high-throughput next-generation sequencing is prone to contaminations due to its high depth of sequencing coverage. Although a few bioinformatics tools are available to detect potential contaminations, these have inherited limitations as they only use protein-coding genes. Here we introduce a new algorithm, called ContEst16S, to detect potential contaminations using 16S rRNA genes from genome assemblies. We screened 69 745 prokaryotic genomes from the NCBI Assembly Database using ContEst16S and found that 594 were contaminated by bacteria, human and plants. Of the predicted contaminated genomes, 8 % were not predicted by the existing protein-coding gene-based tool, implying that both methods can be complementary in the detection of contaminations. A web-based service of the algorithm is available at www.ezbiocloud.net/tools/contest16s.
[Mh] Termos MeSH primário: Algoritmos
Biologia Computacional/métodos
Células Procarióticas
[Mh] Termos MeSH secundário: Bactérias
Seres Humanos
Plantas
RNA Ribossômico 16S/genética
Análise de Sequência de RNA/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170825
[Lr] Data última revisão:
170825
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170623
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.001872


  6 / 2543 MEDLINE  
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[PMID]:28604769
[Au] Autor:Da Cunha V; Gaia M; Gadelle D; Nasir A; Forterre P
[Ad] Endereço:Institut Pasteur, Unité de Biologie Moléculaire du Gène chez les Extrêmophiles (BMGE), Département de Microbiologie Paris, France.
[Ti] Título:Lokiarchaea are close relatives of Euryarchaeota, not bridging the gap between prokaryotes and eukaryotes.
[So] Source:PLoS Genet;13(6):e1006810, 2017 Jun.
[Is] ISSN:1553-7404
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The eocyte hypothesis, in which Eukarya emerged from within Archaea, has been boosted by the description of a new candidate archaeal phylum, "Lokiarchaeota", from metagenomic data. Eukarya branch within Lokiarchaeota in a tree reconstructed from the concatenation of 36 universal proteins. However, individual phylogenies revealed that lokiarchaeal proteins sequences have different evolutionary histories. The individual markers phylogenies revealed at least two subsets of proteins, either supporting the Woese or the Eocyte tree of life. Strikingly, removal of a single protein, the elongation factor EF2, is sufficient to break the Eukaryotes-Lokiarchaea affiliation. Our analysis suggests that the three lokiarchaeal EF2 proteins have a chimeric organization that could be due to contamination and/or homologous recombination with patches of eukaryotic sequences. A robust phylogenetic analysis of RNA polymerases with a new dataset indicates that Lokiarchaeota and related phyla of the Asgard superphylum are sister group to Euryarchaeota, not to Eukarya, and supports the monophyly of Archaea with their rooting in the branch leading to Thaumarchaeota.
[Mh] Termos MeSH primário: Eucariotos/genética
Euryarchaeota/genética
Evolução Molecular
Filogenia
[Mh] Termos MeSH secundário: Proteínas Arqueais/genética
Células Procarióticas
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Archaeal Proteins)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170726
[Lr] Data última revisão:
170726
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170613
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pgen.1006810


  7 / 2543 MEDLINE  
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[PMID]:28569210
[Au] Autor:Zhang J; Gao Q; Zhang Q; Wang T; Yue H; Wu L; Shi J; Qin Z; Zhou J; Zuo J; Yang Y
[Ad] Endereço:State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 10084, China.
[Ti] Título:Bacteriophage-prokaryote dynamics and interaction within anaerobic digestion processes across time and space.
[So] Source:Microbiome;5(1):57, 2017 May 31.
[Is] ISSN:2049-2618
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Bacteriophage-prokaryote dynamics and interaction are believed to be important in governing microbiome composition and ecosystem functions, yet our limited knowledge of the spatial and temporal variation in phage and prokaryotic community compositions precludes accurate assessment of their roles and impacts. Anaerobic digesters are ideal model systems to examine phage-host interaction, owing to easy access, stable operation, nutrient-rich environment, and consequently enormous numbers of phages and prokaryotic cells. RESULTS: Equipped with high-throughput, cutting-edge environmental genomics techniques, we examined phage and prokaryotic community composition of four anaerobic digesters in full-scale wastewater treatment plants across China. Despite the relatively stable process performance in biogas production, phage and prokaryotic groups fluctuated monthly over a year of study period, showing significant correlations between those two groups at the α- and ß-diversity levels. Strikingly, phages explained 40.6% of total variations of the prokaryotic community composition, much higher than the explanatory power by abiotic factors (14.5%). Consequently, phages were significantly (P < 0.010) linked to parameters related to process performance including biogas production and volatile solid concentrations. Association network analyses showed phage-prokaryote pairs were shallowly conserved since they were detected only within small viral clades. CONCLUSIONS: Those results collectively demonstrate phages as a major biotic factor in controlling prokaryotic composition and process performance. Therefore, phages may play a larger role in shaping prokaryotic community dynamics and process performance of anaerobic digesters than currently appreciated.
[Mh] Termos MeSH primário: Bacteriófagos/fisiologia
Biocombustíveis/microbiologia
Células Procarióticas/fisiologia
Águas Residuais/microbiologia
[Mh] Termos MeSH secundário: Anaerobiose
Bacteriófagos/classificação
Biocombustíveis/virologia
Filogenia
Células Procarióticas/classificação
Estações do Ano
Análise de Sequência de DNA/métodos
Águas Residuais/virologia
Purificação da Água
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biofuels); 0 (Waste Water)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170920
[Lr] Data última revisão:
170920
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170602
[St] Status:MEDLINE
[do] DOI:10.1186/s40168-017-0272-8


  8 / 2543 MEDLINE  
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[PMID]:28426242
[Au] Autor:Oikonomou CM; Jensen GJ
[Ad] Endereço:Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125; email: coiko@caltech.edu , jensen@caltech.edu.
[Ti] Título:Cellular Electron Cryotomography: Toward Structural Biology In Situ.
[So] Source:Annu Rev Biochem;86:873-896, 2017 Jun 20.
[Is] ISSN:1545-4509
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Electron cryotomography (ECT) provides three-dimensional views of macromolecular complexes inside cells in a native frozen-hydrated state. Over the last two decades, ECT has revealed the ultrastructure of cells in unprecedented detail. It has also allowed us to visualize the structures of macromolecular machines in their native context inside intact cells. In many cases, such machines cannot be purified intact for in vitro study. In other cases, the function of a structure is lost outside the cell, so that the mechanism can be understood only by observation in situ. In this review, we describe the technique and its history and provide examples of its power when applied to cell biology. We also discuss the integration of ECT with other techniques, including lower-resolution fluorescence imaging and higher-resolution atomic structure determination, to cover the full scale of cellular processes.
[Mh] Termos MeSH primário: Microscopia Crioeletrônica/métodos
Tomografia com Microscopia Eletrônica/métodos
Fímbrias Bacterianas/ultraestrutura
Poro Nuclear/química
Imagem Óptica/métodos
Células Procarióticas/ultraestrutura
[Mh] Termos MeSH secundário: Archaea/metabolismo
Archaea/ultraestrutura
Bactérias/metabolismo
Bactérias/ultraestrutura
Sistemas de Secreção Bacterianos/metabolismo
Sistemas de Secreção Bacterianos/ultraestrutura
Microscopia Crioeletrônica/história
Microscopia Crioeletrônica/instrumentação
Tomografia com Microscopia Eletrônica/história
Tomografia com Microscopia Eletrônica/instrumentação
Fímbrias Bacterianas/metabolismo
Flagelos/metabolismo
Flagelos/ultraestrutura
História do Século XX
História do Século XXI
Modelos Moleculares
Poro Nuclear/metabolismo
Poro Nuclear/ultraestrutura
Imagem Óptica/história
Imagem Óptica/instrumentação
Células Procarióticas/metabolismo
Domínios Proteicos
Estrutura Secundária de Proteína
[Pt] Tipo de publicação:HISTORICAL ARTICLE; JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Bacterial Secretion Systems)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170714
[Lr] Data última revisão:
170714
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170421
[St] Status:MEDLINE
[do] DOI:10.1146/annurev-biochem-061516-044741


  9 / 2543 MEDLINE  
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[PMID]:28420737
[Au] Autor:Kim JS; Wood TK
[Ad] Endereço:Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania, USA.
[Ti] Título:Tolerant, Growing Cells from Nutrient Shifts Are Not Persister Cells.
[So] Source:MBio;8(2), 2017 Apr 18.
[Is] ISSN:2150-7511
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:There is much controversy about the metabolic state of cells that are tolerant to antibiotics, known as persister cells. In this opinion piece, we offer an explanation for the discrepancy seen: some laboratories are studying metabolically active and growing cell populations (e.g., as a result of nutrient shifts) and attributing the phenotypes that they discern to persister cells while other labs are studying dormant cells. We argue here that the metabolically active cell population should more accurately be considered tolerant cells, while the dormant cells are the true persister population.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Tolerância a Medicamentos
Células Procarióticas/efeitos dos fármacos
Células Procarióticas/fisiologia
[Mh] Termos MeSH secundário: Células Procarióticas/classificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170502
[Lr] Data última revisão:
170502
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170420
[St] Status:MEDLINE


  10 / 2543 MEDLINE  
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[PMID]:28409190
[Au] Autor:Salah Ud-Din AIM; Roujeinikova A
[Ad] Endereço:Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, VIC, Australia.
[Ti] Título:Methyl-accepting chemotaxis proteins: a core sensing element in prokaryotes and archaea.
[So] Source:Cell Mol Life Sci;74(18):3293-3303, 2017 Sep.
[Is] ISSN:1420-9071
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Chemotaxis is the directed motility by means of which microbes sense chemical cues and relocate towards more favorable environments. Methyl-accepting chemotaxis proteins (MCPs) are the most common receptors in bacteria and archaea. They are arranged as trimers of dimers that, in turn, form hexagonal arrays in the cytoplasmic membrane or in the cytoplasm. Several different classes of MCPs have been identified according to their ligand binding region and membrane topology. MCPs have been further classified based on the length and sequence conservation of their cytoplasmic domains. Clusters of membrane-embedded MCPs often localize to the poles of the cell, whereas cytoplasmic MCPs can be targeted to the poles or distributed throughout the cell body. MCPs play an important role in cell survival, pathogenesis, and biodegradation. Bacterial adaptation to diverse environmental conditions promotes diversity among the MCPs. This review summarizes structure, classification, and structure-activity relationship of the known MCP receptors, with a brief overview of the signal transduction mechanisms in bacteria and archaea.
[Mh] Termos MeSH primário: Archaea/metabolismo
Proteínas Quimiotáticas Aceptoras de Metil/metabolismo
Células Procarióticas/metabolismo
[Mh] Termos MeSH secundário: Archaea/classificação
Quimiotaxia
Proteínas de Membrana/química
Proteínas de Membrana/metabolismo
Proteínas Quimiotáticas Aceptoras de Metil/química
Células Procarióticas/classificação
Domínios Proteicos
Transdução de Sinais
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Membrane Proteins); 0 (Methyl-Accepting Chemotaxis Proteins)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170415
[St] Status:MEDLINE
[do] DOI:10.1007/s00018-017-2514-0



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