Base de dados : MEDLINE
Pesquisa : A11.284.430.214.190.875.811.870.700.700 [Categoria DeCS]
Referências encontradas : 170 [refinar]
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  1 / 170 MEDLINE  
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[PMID]:28977617
[Au] Autor:Yang K; Chang JY; Cui Z; Li X; Meng R; Duan L; Thongchol J; Jakana J; Huwe CM; Sacchettini JC; Zhang J
[Ad] Endereço:Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA.
[Ti] Título:Structural insights into species-specific features of the ribosome from the human pathogen Mycobacterium tuberculosis.
[So] Source:Nucleic Acids Res;45(18):10884-10894, 2017 Oct 13.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Ribosomes from Mycobacterium tuberculosis (Mtb) possess species-specific ribosomal RNA (rRNA) expansion segments and ribosomal proteins (rProtein). Here, we present the near-atomic structures of the Mtb 50S ribosomal subunit and the complete Mtb 70S ribosome, solved by cryo-electron microscopy. Upon joining of the large and small ribosomal subunits, a 100-nt long expansion segment of the Mtb 23S rRNA, named H54a or the 'handle', switches interactions from with rRNA helix H68 and rProtein uL2 to with rProtein bS6, forming a new intersubunit bridge 'B9'. In Mtb 70S, bridge B9 is mostly maintained, leading to correlated motions among the handle, the L1 stalk and the small subunit in the rotated and non-rotated states. Two new protein densities were discovered near the decoding center and the peptidyl transferase center, respectively. These results provide a structural basis for studying translation in Mtb as well as developing new tuberculosis drugs.
[Mh] Termos MeSH primário: Mycobacterium tuberculosis/química
Ribossomos/química
[Mh] Termos MeSH secundário: Microscopia Crioeletrônica
Modelos Moleculares
Movimento (Física)
Mycobacterium smegmatis/química
Inibidores da Síntese de Proteínas
Proteínas Ribossômicas/química
Subunidades Ribossômicas Maiores de Bactérias/química
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Protein Synthesis Inhibitors); 0 (Ribosomal Proteins)
[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:171005
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkx785


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[PMID]:28786986
[Au] Autor:Wu J; Ma YB; Congdon C; Brett B; Chen S; Xu Y; Ouyang Q; Mao Y
[Ad] Endereço:State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, Institute of Condensed Matter Physics, School of Physics, Center for Quantitative Biology, Peking University, Beijing, China.
[Ti] Título:Massively parallel unsupervised single-particle cryo-EM data clustering via statistical manifold learning.
[So] Source:PLoS One;12(8):e0182130, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Structural heterogeneity in single-particle cryo-electron microscopy (cryo-EM) data represents a major challenge for high-resolution structure determination. Unsupervised classification may serve as the first step in the assessment of structural heterogeneity. However, traditional algorithms for unsupervised classification, such as K-means clustering and maximum likelihood optimization, may classify images into wrong classes with decreasing signal-to-noise-ratio (SNR) in the image data, yet demand increased computational costs. Overcoming these limitations requires further development of clustering algorithms for high-performance cryo-EM data processing. Here we introduce an unsupervised single-particle clustering algorithm derived from a statistical manifold learning framework called generative topographic mapping (GTM). We show that unsupervised GTM clustering improves classification accuracy by about 40% in the absence of input references for data with lower SNRs. Applications to several experimental datasets suggest that our algorithm can detect subtle structural differences among classes via a hierarchical clustering strategy. After code optimization over a high-performance computing (HPC) environment, our software implementation was able to generate thousands of reference-free class averages within hours in a massively parallel fashion, which allows a significant improvement on ab initio 3D reconstruction and assists in the computational purification of homogeneous datasets for high-resolution visualization.
[Mh] Termos MeSH primário: Microscopia Crioeletrônica
Processamento de Imagem Assistida por Computador/métodos
Aprendizado de Máquina não Supervisionado
[Mh] Termos MeSH secundário: Análise por Conglomerados
Simulação por Computador
Microscopia Crioeletrônica/métodos
Escherichia coli
Imagem Tridimensional/métodos
Inflamassomos/ultraestrutura
Análise Multivariada
Análise de Componente Principal
Complexo de Endopeptidases do Proteassoma/ultraestrutura
Subunidades Ribossômicas Maiores de Bactérias/ultraestrutura
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Inflammasomes); EC 3.4.25.1 (Proteasome Endopeptidase Complex); EC 3.4.99.- (ATP dependent 26S protease)
[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:170809
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0182130


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[PMID]:28573789
[Au] Autor:Choi W; Yamaguchi Y; Lee JW; Jang KM; Inouye M; Kim SG; Yoon MH; Park JH
[Ad] Endereço:Bio-Evaluation Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju, South Korea.
[Ti] Título:Translation-dependent mRNA cleavage by YhaV in Escherichia coli.
[So] Source:FEBS Lett;591(13):1853-1861, 2017 Jul.
[Is] ISSN:1873-3468
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Many bacteria have toxin-antitoxin (TA) systems, where toxin gene expression inhibits their own cell growth. mRNA is one of the well-known targets of the toxins in the type II toxin-antitoxin systems. Here, we examined the ribosome dependency of the endoribonuclease activity of YhaV, one of the toxins in type II TA systems, on mRNA in vitro and in vivo. A polysome profiling assay revealed that YhaV is bound to the 70S ribosomes and 50S ribosomal subunits. Moreover, we found that while YhaV cleaves ompF and lpp mRNAs in a translation-dependent manner, they did not cleave the 5' untranslated region in primer extension experiments. From these results, we conclude that YhaV is a ribosome-dependent toxin that cleaves mRNA in a translation-dependent manner.
[Mh] Termos MeSH primário: Toxinas Bacterianas/metabolismo
Proteínas de Escherichia coli/metabolismo
Escherichia coli/genética
Escherichia coli/metabolismo
Biossíntese de Proteínas
Clivagem do RNA
[Mh] Termos MeSH secundário: Proteínas da Membrana Bacteriana Externa/genética
Escherichia coli/citologia
Proteínas de Escherichia coli/genética
Lipoproteínas/genética
Porinas/genética
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
Subunidades Ribossômicas Maiores de Bactérias/metabolismo
Ribossomos/metabolismo
[Pt] Tipo de publicação:LETTER
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Bacterial Toxins); 0 (Escherichia coli Proteins); 0 (Lipoproteins); 0 (Lpp protein, E coli); 0 (OmpF protein); 0 (Porins); 0 (RNA, Messenger); 0 (yhaV protein, E coli)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170603
[St] Status:MEDLINE
[do] DOI:10.1002/1873-3468.12705


  4 / 170 MEDLINE  
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[PMID]:28114288
[Au] Autor:van de Waterbeemd M; Fort KL; Boll D; Reinhardt-Szyba M; Routh A; Makarov A; Heck AJ
[Ad] Endereço:Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, the Netherlands.
[Ti] Título:High-fidelity mass analysis unveils heterogeneity in intact ribosomal particles.
[So] Source:Nat Methods;14(3):283-286, 2017 Mar.
[Is] ISSN:1548-7105
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Investigation of the structure, assembly and function of protein-nucleic acid macromolecular machines requires multidimensional molecular and structural biology approaches. We describe modifications to an Orbitrap mass spectrometer, enabling high-resolution native MS analysis of 0.8- to 2.3-MDa prokaryotic 30S, 50S and 70S ribosome particles and the 9-MDa Flock House virus. The instrument's improved mass range and sensitivity readily exposes unexpected binding of the ribosome-associated protein SRA.
[Mh] Termos MeSH primário: Escherichia coli/citologia
Espectrometria de Massas/métodos
Nodaviridae/ultraestrutura
RNA Longo não Codificante/metabolismo
Subunidades Ribossômicas Maiores de Bactérias/ultraestrutura
Subunidades Ribossômicas Menores de Bactérias/ultraestrutura
[Mh] Termos MeSH secundário: Espectrometria de Massas/instrumentação
Nodaviridae/genética
Ligação Proteica/fisiologia
Subunidades Ribossômicas Maiores de Bactérias/genética
Subunidades Ribossômicas Menores de Bactérias/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Long Noncoding); 0 (steroid receptor RNA activator)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170626
[Lr] Data última revisão:
170626
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170124
[St] Status:MEDLINE
[do] DOI:10.1038/nmeth.4147


  5 / 170 MEDLINE  
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[PMID]:28099529
[Au] Autor:Das D; Samanta D; Bhattacharya A; Basu A; Das A; Ghosh J; Chakrabarti A; Das Gupta C
[Ad] Endereço:Department of Biophysics, Molecular Biology and Bioinformatics, University College of Science, University of Calcutta, Kolkata, India.
[Ti] Título:A Possible Role of the Full-Length Nascent Protein in Post-Translational Ribosome Recycling.
[So] Source:PLoS One;12(1):e0170333, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Each cycle of translation initiation in bacterial cell requires free 50S and 30S ribosomal subunits originating from the post-translational dissociation of 70S ribosome from the previous cycle. Literature shows stable dissociation of 70S from model post-termination complexes by the concerted action of Ribosome Recycling Factor (RRF) and Elongation Factor G (EF-G) that interact with the rRNA bridge B2a/B2b joining 50S to 30S. In such experimental models, the role of full-length nascent protein was never considered seriously. We observed relatively slow release of full-length nascent protein from 50Sof post translation ribosome, and in that process, its toe prints on the rRNA in vivo and in in vitro translation with E.coli S30 extract. We reported earlier that a number of chemically unfolded proteins like bovine carbonic anhydrase (BCA), lactate dehydrogenase (LDH), malate dehydrogenase (MDH), lysozyme, ovalbumin etc., when added to free 70Sin lieu of the full length nascent proteins, also interact with identical RNA regions of the 23S rRNA. Interestingly the rRNA nucleotides that slow down release of the C-terminus of full-length unfolded protein were found in close proximity to the B2a/B2b bridge. It indicated a potentially important chemical reaction conserved throughout the evolution. Here we set out to probe that conserved role of unfolded protein conformation in splitting the free or post-termination 70S. How both the RRF-EFG dependent and the plausible nascent protein-EFG dependent ribosome recycling pathways might be relevant in bacteria is discussed here.
[Mh] Termos MeSH primário: Escherichia coli/metabolismo
Iniciação Traducional da Cadeia Peptídica/fisiologia
Terminação Traducional da Cadeia Peptídica/fisiologia
Biossíntese de Proteínas/fisiologia
Subunidades Ribossômicas Maiores de Bactérias/metabolismo
Subunidades Ribossômicas Menores de Bactérias/metabolismo
[Mh] Termos MeSH secundário: Animais
Anidrases Carbônicas/metabolismo
Bovinos
Embrião de Galinha
Escherichia coli/genética
L-Lactato Desidrogenase/metabolismo
Malato Desidrogenase/metabolismo
Muramidase/metabolismo
Ovalbumina/metabolismo
Fator G para Elongação de Peptídeos/metabolismo
Dobramento de Proteína
Proteínas Ribossômicas/metabolismo
Suínos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Peptide Elongation Factor G); 0 (Ribosomal Proteins); 0 (ribosome releasing factor); 9006-59-1 (Ovalbumin); EC 1.1.1.27 (L-Lactate Dehydrogenase); EC 1.1.1.37 (Malate Dehydrogenase); EC 3.2.1.17 (Muramidase); EC 4.2.1.1 (Carbonic Anhydrases)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170816
[Lr] Data última revisão:
170816
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170119
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0170333


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[PMID]:28068600
[Au] Autor:Gao ML; Zeng J; Fang X; Luo J; Jin Z; Liu YH; Tang YZ
[Ad] Endereço:Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
[Ti] Título:Design, synthesis and antibacterial evaluation of novel pleuromutilin derivatives possessing piperazine linker.
[So] Source:Eur J Med Chem;127:286-295, 2017 Feb 15.
[Is] ISSN:1768-3254
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:A series of pleuromutilin derivatives bearing piperazine ring have been reported. The in vitro antibacterial activities of the synthetic derivatives against MRSA (ATCC 43300), Staphylococcus aureus (ATCC 29213), Enterococcus faecalis (ATCC 29212), Enterococcus faecium (ATCC35667) and Escherichia coli (ATCC25922) were evaluated by the broth dilution method. Most of the synthesized derivatives displayed potent activities. Compounds 11c, 12a and 12c were found to be the most active antibacterial derivatives against MRSA (minimum inhibitory concentration = 0.015 µg/mL). The binding of compounds 11c, 12a and 12c to the 50s ribosome were investigated by molecular modeling. Compound 11c possessed lower binding free energy compared with compounds 12a and 12c. Compound 11c was further evaluated in MRSA systemic infection model and displayed superior in vivo efficacy to that of tiamulin.
[Mh] Termos MeSH primário: Antibacterianos/síntese química
Antibacterianos/farmacologia
Desenho de Drogas
Piperazinas/química
[Mh] Termos MeSH secundário: Antibacterianos/química
Antibacterianos/metabolismo
Técnicas de Química Sintética
Diterpenos/síntese química
Diterpenos/química
Diterpenos/metabolismo
Diterpenos/farmacologia
Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos
Testes de Sensibilidade Microbiana
Conformação Molecular
Simulação de Acoplamento Molecular
Subunidades Ribossômicas Maiores de Bactérias/química
Subunidades Ribossômicas Maiores de Bactérias/metabolismo
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Diterpenes); 0 (Piperazines); 125-65-5 (pleuromutilin); 1RTM4PAL0V (piperazine)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170228
[Lr] Data última revisão:
170228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170110
[St] Status:MEDLINE


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[PMID]:27986852
[Au] Autor:López-Alonso JP; Fabbretti A; Kaminishi T; Iturrioz I; Brandi L; Gil-Carton D; Gualerzi CO; Fucini P; Connell SR
[Ad] Endereço:Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, 48160 Derio, Bizkaia, Spain.
[Ti] Título:Structure of a 30S pre-initiation complex stalled by GE81112 reveals structural parallels in bacterial and eukaryotic protein synthesis initiation pathways.
[So] Source:Nucleic Acids Res;45(4):2179-2187, 2017 Feb 28.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In bacteria, the start site and the reading frame of the messenger RNA are selected by the small ribosomal subunit (30S) when the start codon, typically an AUG, is decoded in the P-site by the initiator tRNA in a process guided and controlled by three initiation factors. This process can be efficiently inhibited by GE81112, a natural tetrapeptide antibiotic that is highly specific toward bacteria. Here GE81112 was used to stabilize the 30S pre-initiation complex and obtain its structure by cryo-electron microscopy. The results obtained reveal the occurrence of changes in both the ribosome conformation and initiator tRNA position that may play a critical role in controlling translational fidelity. Furthermore, the structure highlights similarities with the early steps of initiation in eukaryotes suggesting that shared structural features guide initiation in all kingdoms of life.
[Mh] Termos MeSH primário: Iniciação Traducional da Cadeia Peptídica
RNA Mensageiro/genética
RNA de Transferência de Metionina/genética
Subunidades Ribossômicas Menores de Bactérias/metabolismo
[Mh] Termos MeSH secundário: Sítios de Ligação
Escherichia coli/genética
Escherichia coli/metabolismo
Células Eucarióticas/metabolismo
Modelos Moleculares
Conformação Molecular
Fatores de Iniciação em Procariotos/química
Fatores de Iniciação em Procariotos/metabolismo
Biossíntese de Proteínas/genética
RNA Mensageiro/química
RNA Mensageiro/metabolismo
RNA de Transferência de Metionina/química
RNA de Transferência de Metionina/metabolismo
Subunidades Ribossômicas Maiores de Bactérias/química
Subunidades Ribossômicas Maiores de Bactérias/metabolismo
Subunidades Ribossômicas Menores de Bactérias/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Prokaryotic Initiation Factors); 0 (RNA, Messenger); 0 (RNA, Transfer, Met)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171002
[Lr] Data última revisão:
171002
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161218
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkw1251


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[PMID]:27858985
[Au] Autor:Thoduka SG; Zaleski PA; Dabrowska Z; Równicki M; Strózecka J; Górska A; Olejniczak M; Trylska J
[Ad] Endereço:Centre of New Technologies, University of Warsaw, Warsaw, 02-097, Poland.
[Ti] Título:Analysis of ribosomal inter-subunit sites as targets for complementary oligonucleotides.
[So] Source:Biopolymers;107(4), 2017 Apr.
[Is] ISSN:1097-0282
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The bacterial ribosome has many functional ribosomal RNA (rRNA) sites. We have computationally analyzed the rRNA regions involved in the interactions between the 30S and 50S subunits. Various properties of rRNA such as solvent accessibility, opening energy, hydrogen bonding pattern, van der Waals energy, thermodynamic stability were determined. Based on these properties we selected rRNA targets for hybridization with complementary 2'-O-methyl oligoribonucleotides (2'-OMe RNAs). Further, the inhibition efficiencies of the designed ribosome-interfering 2'-OMe RNAs were tested using a ß-galactosidase assay in a translation system based on the E. coli extract. Several of the oligonucleotides displayed IC values below 1 µM, which were in a similar range as those determined for known ribosome inhibitors, tetracycline and pactamycin. The calculated opening and van der Waals stacking energies of the rRNA targets correlated best with the inhibitory efficiencies of 2'-OMe RNAs. Moreover, the binding affinities of several oligonucleotides to both 70S ribosomes and isolated 30S and 50S subunits were measured using a double-filter retention assay. Further, we applied heat-shock chemical transformation to introduce 2'-OMe RNAs to E. coli cells and verify inhibition of bacterial growth. We observed high correlation between IC in the cell-free extract and bacterial growth inhibition. Overall, the results suggest that the computational analysis of potential rRNA targets within the conformationally dynamic regions of inter-subunit bridges can help design efficient antisense oligomers to probe the ribosome function.
[Mh] Termos MeSH primário: Oligonucleotídeos/metabolismo
RNA Ribossômico/metabolismo
[Mh] Termos MeSH secundário: Sequência de Bases
Sítios de Ligação
Projeto Auxiliado por Computador
Escherichia coli/efeitos dos fármacos
Escherichia coli/genética
Escherichia coli/metabolismo
Conformação de Ácido Nucleico
Oligonucleotídeos/química
Pactamicina/química
Pactamicina/metabolismo
Pactamicina/farmacologia
Ligação Proteica
Biossíntese de Proteínas/efeitos dos fármacos
Estrutura Terciária de Proteína
RNA Ribossômico/antagonistas & inibidores
RNA Ribossômico/química
Subunidades Ribossômicas Maiores de Bactérias/química
Subunidades Ribossômicas Maiores de Bactérias/metabolismo
Subunidades Ribossômicas Menores de Bactérias/química
Subunidades Ribossômicas Menores de Bactérias/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Oligonucleotides); 0 (RNA, Ribosomal); 23668-11-3 (Pactamycin)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170207
[Lr] Data última revisão:
170207
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161119
[St] Status:MEDLINE
[do] DOI:10.1002/bip.23004


  9 / 170 MEDLINE  
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[PMID]:27830472
[Au] Autor:Roberts R; Pietersen G
[Ad] Endereço:Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, 0002, South Africa.
[Ti] Título:A novel subspecies of 'Candidatus Liberibacter africanus' found on native Teclea gerrardii (Family: Rutaceae) from South Africa.
[So] Source:Antonie Van Leeuwenhoek;110(3):437-444, 2017 Mar.
[Is] ISSN:1572-9699
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The phloem limited bacterium 'Candidatus Liberibacter africanus' is associated with citrus greening disease in South Africa. This bacterium has been identified solely from commercial citrus in Africa and the Mascarene islands, and its origin may lie within an indigenous rutaceous host from Africa. Recently, in determining whether alternative hosts of Laf exist amongst the indigenous rutaceous hosts of its triozid vector, Trioza erytreae, three novel subspecies of Laf were identified i.e. 'Candidatus Liberibacter africanus subsp. clausenae', 'Candidatus Liberibacter africanus subsp. vepridis' and 'Candidatus Liberibacter africanus subsp. zanthoxyli' in addition to the formerly identified 'Candidatus Liberibacter africanus subsp. capensis'. The current study expands upon the range of indigenous rutaceous tree species tested for liberibacters closely related to Laf and its subspecies. A collection of 121 samples of Teclea and Oricia species were sampled from Oribi Gorge and Umtamvunu nature reserves in KwaZulu Natal. Total DNA was extracted and the presence of liberibacters from these samples determined using a generic liberibacter TaqMan real-time PCR assay. Liberibacters from positive samples were further characterised through amplification and sequencing of the 16S rRNA, outer-membrane protein (omp) and 50S ribosomal protein L10 (rplJ) genes. A single Teclea gerrardii specimen tested positive for a liberibacter and, through phylogenetic analyses of the three genes sequenced, was shown to be unique, albeit closely related to 'Ca. L. africanus' and 'Ca. L. africanus subsp. zanthoxyli'. We propose that this newly identified liberibacter be named 'Candidatus Liberibacter africanus subsp. tecleae'.
[Mh] Termos MeSH primário: Citrus/microbiologia
Doenças das Plantas/microbiologia
Rhizobiaceae/classificação
Rhizobiaceae/isolamento & purificação
[Mh] Termos MeSH secundário: DNA Bacteriano/genética
Genes Bacterianos
Proteínas de Membrana/genética
Filogenia
RNA Ribossômico 16S/genética
Rhizobiaceae/genética
Rhizobiaceae/patogenicidade
Subunidades Ribossômicas Maiores de Bactérias/classificação
Subunidades Ribossômicas Maiores de Bactérias/genética
Análise de Sequência de DNA
África do Sul
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Membrane Proteins); 0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170328
[Lr] Data última revisão:
170328
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161111
[St] Status:MEDLINE
[do] DOI:10.1007/s10482-016-0799-x


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[PMID]:27912064
[Au] Autor:Davis JH; Tan YZ; Carragher B; Potter CS; Lyumkis D; Williamson JR
[Ad] Endereço:Department of Integrative Structural and Computational Biology, Department of Chemistry, and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
[Ti] Título:Modular Assembly of the Bacterial Large Ribosomal Subunit.
[So] Source:Cell;167(6):1610-1622.e15, 2016 Dec 01.
[Is] ISSN:1097-4172
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The ribosome is a complex macromolecular machine and serves as an ideal system for understanding biological macromolecular assembly. Direct observation of ribosome assembly in vivo is difficult, as few intermediates have been isolated and thoroughly characterized. Herein, we deploy a genetic system to starve cells of an essential ribosomal protein, which results in the accumulation of assembly intermediates that are competent for maturation. Quantitative mass spectrometry and single-particle cryo-electron microscopy reveal 13 distinct intermediates, which were each resolved to ∼4-5 Å resolution and could be placed in an assembly pathway. We find that ribosome biogenesis is a parallel process, that blocks of structured rRNA and proteins assemble cooperatively, and that the entire process is dynamic and can be "re-routed" through different pathways as needed. This work reveals the complex landscape of ribosome assembly in vivo and provides the requisite tools to characterize additional assembly pathways for ribosomes and other macromolecular machines.
[Mh] Termos MeSH primário: Escherichia coli/química
Escherichia coli/metabolismo
Subunidades Ribossômicas Maiores de Bactérias/química
Subunidades Ribossômicas Maiores de Bactérias/metabolismo
[Mh] Termos MeSH secundário: Microscopia Crioeletrônica
Espectrometria de Massas
Modelos Moleculares
Multimerização Proteica
RNA Bacteriano/metabolismo
RNA Ribossômico/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Bacterial); 0 (RNA, Ribosomal)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170509
[Lr] Data última revisão:
170509
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161203
[St] Status:MEDLINE



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