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  1 / 1320 MEDLINE  
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[PMID]:28981257
[Au] Autor:Schnicker NJ; Razzaghi M; Guha Thakurta S; Chakravarthy S; Dey M
[Ad] Endereço:Department of Chemistry, The University of Iowa , Iowa City, Iowa 52242, United States.
[Ti] Título:Bacillus anthracis Prolyl 4-Hydroxylase Interacts with and Modifies Elongation Factor Tu.
[So] Source:Biochemistry;56(43):5771-5785, 2017 Oct 31.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Prolyl hydroxylation is a very common post-translational modification and plays many roles in eukaryotes such as collagen stabilization, hypoxia sensing, and controlling protein transcription and translation. There is a growing body of evidence that suggests that prokaryotes contain prolyl 4-hydroxylases (P4Hs) homologous to the hypoxia-inducible factor (HIF) prolyl hydroxylase domain (PHD) enzymes that act on elongation factor Tu (EFTu) and are likely involved in the regulation of bacterial translation. Recent biochemical and structural studies with a PHD from Pseudomonas putida (PPHD) determined that it forms a complex with EFTu and hydroxylates a prolyl residue of EFTu. Moreover, while animal, plant, and viral P4Hs act on peptidyl proline, most prokaryotic P4Hs have been known to target free l-proline; the exceptions include PPHD and a P4H from Bacillus anthracis (BaP4H) that modifies collagen-like proline-rich peptides. Here we use biophysical and mass spectrometric methods to demonstrate that BaP4H recognizes full-length BaEFTu and a BaEFTu 9-mer peptide for site-specific proline hydroxylation. Using size-exclusion chromatography coupled small-angle X-ray scattering (SEC-SAXS) and binding studies, we determined that BaP4H forms a 1:1 heterodimeric complex with BaEFTu. The SEC-SAXS studies reveal dissociation of BaP4H dimeric subunits upon interaction with BaEFTu. While BaP4H is unusual within bacteria in that it is structurally and functionally similar to the animal PHDs and collagen P4Hs, respectively, this work provides further evidence of its promiscuous substrate recognition. It is possible that the enzyme might have evolved to hydroxylate a universally conserved protein in prokaryotes, similar to the PHDs, and implies a functional role in B. anthracis.
[Mh] Termos MeSH primário: Bacillus anthracis/metabolismo
Proteínas de Bactérias/metabolismo
Fator Tu de Elongação de Peptídeos/metabolismo
Prolil Hidroxilases/metabolismo
[Mh] Termos MeSH secundário: Bacillus anthracis/química
Bacillus anthracis/genética
Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Fator Tu de Elongação de Peptídeos/química
Fator Tu de Elongação de Peptídeos/genética
Prolil Hidroxilases/química
Prolil Hidroxilases/genética
Ligação Proteica
Domínios Proteicos
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); EC 1.14.11.- (Prolyl Hydroxylases); EC 3.6.1.- (Peptide Elongation Factor Tu)
[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:171006
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00601


  2 / 1320 MEDLINE  
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[PMID]:28865219
[Au] Autor:Xia XJ; Wang L; Cheng LK; Shen ZQ; Li SG; Wang JL
[Ad] Endereço:.
[Ti] Título:Expression and immunological evaluation of elongation factor Tu of Streptococcus suis serotype 2.
[So] Source:Pol J Vet Sci;20(2):277-284, 2017 Mar 01.
[Is] ISSN:1505-1773
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Streptococcus suis serotype 2 (SS2) is considered as a major pathogen that causes sepsis and meningitis in piglets and humans, but knowledge of its antigenic proteins remains limited so far. The surface-related proteins of pathogens often play significant roles in bacterium-host interactions and infection. Here, we obtained the elongation factor Tu (EF-Tu) gene of Streptococcus suis and constructed the recombinant expression plasmid successfully. The target recombinant plasmid was then expressed in Escherichia coli and the immuno-protection of the recombinant protein was subsequently evaluated as well. The EF-Tu gene of Streptococcus suis is 1197 bp in length, encodes 398 amino acids. The target recombinant EF-Tu (rEF-Tu) protein can recognize the antiserum of Streptococcus suis and can provoke obvious humoral immune responses in rabbits and conferred protection to rabbits against Streptococcus suis ear-vein challenge, implying that the EF-Tu may be used as an attractive candidate antigen for a component of subunit vaccine.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Regulação Bacteriana da Expressão Gênica/fisiologia
Fator Tu de Elongação de Peptídeos/metabolismo
Streptococcus suis/metabolismo
[Mh] Termos MeSH secundário: Animais
Anticorpos Antibacterianos/sangue
Proteínas de Bactérias/genética
Vacinas Bacterianas/imunologia
Clonagem Molecular
Fator Tu de Elongação de Peptídeos/genética
Coelhos
Sorogrupo
Infecções Estreptocócicas/microbiologia
Infecções Estreptocócicas/prevenção & controle
Streptococcus suis/genética
Streptococcus suis/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Bacterial); 0 (Bacterial Proteins); 0 (Bacterial Vaccines); EC 3.6.1.- (Peptide Elongation Factor Tu)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171106
[Lr] Data última revisão:
171106
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170903
[St] Status:MEDLINE


  3 / 1320 MEDLINE  
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[PMID]:28736082
[Au] Autor:Cha S; Shin DH; Seok JR; Myung JK
[Ad] Endereço:Department of Cancer Biomedical Science, National Cancer Centre Graduate School of Cancer Science and Policy, Goyang-si, Gyeonggi-do, Republic of Korea.
[Ti] Título:Differential proteome expression analysis of androgen-dependent and -independent pathways in LNCaP prostate cancer cells.
[So] Source:Exp Cell Res;359(1):215-225, 2017 Oct 01.
[Is] ISSN:1090-2422
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Prostate cancer (PC) is one of the leading causes of cancer death in men. It commonly develops in older males, but the number of younger men diagnosed with the disease has increased in recent years. Hormone therapies, such as chemical and surgical methods that inhibit androgen synthesis or androgen receptor (AR) activation, have been used for advanced disease. However, castration-resistant PC (CRPC), which exhibits androgen-independent mechanisms for activating AR, develops after a few years of such treatment and no therapy is available. In this study, we examined differences in the proteomes associated with the androgen-dependent (DHT treatment) and -independent (FSK, forskolin treatment) AR signaling conditions in LNCaP prostate cancer cells. Moreover, we used EPI-001, which inhibits AR-mediated transcriptional activity, to examine whether the observed differences in protein expression were directly affected by AR-mediated mechanisms. A total of 213 protein spots were matched in our 2-dimensional gel electrophoresis (2DE) analysis and 8 proteins with significant expression changes in our 5 different treatment groups were identified by mass spectrometry. Among these proteins, expression levels of PEPCK-M, catalase, tubulin alpha chain, alpha-enolase, and endoplasmic reticulum resident protein 29 were significantly altered by DHT and the levels of HSP 90 and EF-Tu were changed by FSK. These changes were blocked by EPI-001 in DHT-regulated proteins, PEPCK-M, catalase, and tubulin alpha chain and FSK-regulated EF-Tu protein. The results from our immunohistochemical analysis using in vivo xenograft models were consistent with the 2DE data. We therefore report the first identification of differences in proteins that are significantly regulated under androgen-dependent and -independent AR signaling conditions. Our findings could suggest a possible molecular mechanism through which AR is activated in the absence and/or presence of androgen, and might help explain the inhibitory action of EPI-001 on CRPC.
[Mh] Termos MeSH primário: Androgênios/farmacologia
Neoplasias da Próstata/metabolismo
Proteoma/metabolismo
Transdução de Sinais/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Compostos Benzidrílicos/farmacologia
Linhagem Celular Tumoral
Cloridrinas/farmacologia
Colforsina/farmacologia
Di-Hidrotestosterona/farmacologia
Eletroforese em Gel Bidimensional
Seres Humanos
Imuno-Histoquímica
Masculino
Camundongos
Fator Tu de Elongação de Peptídeos/metabolismo
Fosfoenolpiruvato Carboxiquinase (ATP)/metabolismo
Neoplasias da Próstata/patologia
Proteômica
Espectrometria de Massas em Tandem
Tubulina (Proteína)/metabolismo
Ensaios Antitumorais Modelo de Xenoenxerto
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Androgens); 0 (Benzhydryl Compounds); 0 (Chlorohydrins); 0 (EPI 001); 0 (Proteome); 0 (Tubulin); 08J2K08A3Y (Dihydrotestosterone); 1F7A44V6OU (Colforsin); EC 3.6.1.- (Peptide Elongation Factor Tu); EC 4.1.1.49 (PEPCK-M protein, mouse); EC 4.1.1.49 (Phosphoenolpyruvate Carboxykinase (ATP))
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170725
[St] Status:MEDLINE


  4 / 1320 MEDLINE  
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[PMID]:28645610
[Au] Autor:Wang B; Ao J; Yu D; Rao T; Ruan Y; Yao X
[Ad] Endereço:Department of Urology, The First People's Hospital of Jiangxia District Wuhan City, Wuhan 430200, China. Electronic address: Drskywang@163.com.
[Ti] Título:Inhibition of mitochondrial translation effectively sensitizes renal cell carcinoma to chemotherapy.
[So] Source:Biochem Biophys Res Commun;490(3):767-773, 2017 Aug 26.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The functional importance of mitochondrial protein translation has been recently documented in the context of various cancers but not renal cell carcinoma (RCC). In lines with these efforts, our work demonstrates that mitochondrial translation inhibition by tigecycline or depletion of EF-Tu mitochondrial translation factor effectively targets RCC and significantly sensitizes RCC response to chemotherapy. We show that antibiotic tigecycline inhibits multiple biological functions of RCC, including growth, colony formation and survival. It also significantly enhances in vitro and in vivo efficacy of paclitaxel in RCC. Tigecycline preferentially inhibits translation of mitochondrial DNA-encoded proteins, activities of mitochondrial respiratory complexes that contain mitochondrially encoded subunits. As a consequence of mitochondrial respiratory chain inhibition, decreased mitochondrial respiration is observed in RCC cells exposed to tigecycline. In contrast, tigecycline is ineffective in RCC ρ0 cells that lack mitochondrial DNA and subsequent mitochondrial respiration, further confirm mitochondrial translation inhibition as the mechanism of tigecycline's action in RCC. Importantly, genetic inhibition of mitochondrial translation by EF-Tu knockdown reproduced the inhibitory effects of tigecycline. Finally, we show the association between mitochondrial translation inhibition and suppression of PI3K/Akt/mTOR signaling pathway. Our work used pharmacological and genetic strategies to demonstrate the important roles of mitochondrial translation in RCC and emphasize the therapeutic value of sensitizing RCC to chemotherapy.
[Mh] Termos MeSH primário: Antibacterianos/uso terapêutico
Antineoplásicos Fitogênicos/uso terapêutico
Carcinoma de Células Renais/tratamento farmacológico
Neoplasias Renais/tratamento farmacológico
Rim/efeitos dos fármacos
Minociclina/análogos & derivados
Paclitaxel/uso terapêutico
Biossíntese de Proteínas/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Antibacterianos/farmacologia
Antineoplásicos Fitogênicos/farmacologia
Carcinoma de Células Renais/genética
Carcinoma de Células Renais/patologia
Linhagem Celular Tumoral
DNA Mitocondrial/genética
Seres Humanos
Rim/metabolismo
Rim/patologia
Neoplasias Renais/genética
Neoplasias Renais/patologia
Masculino
Camundongos Endogâmicos BALB C
Minociclina/farmacologia
Minociclina/uso terapêutico
Mitocôndrias/efeitos dos fármacos
Mitocôndrias/genética
Mitocôndrias/patologia
Paclitaxel/farmacologia
Fator Tu de Elongação de Peptídeos/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Antineoplastic Agents, Phytogenic); 0 (DNA, Mitochondrial); 70JE2N95KR (tigecycline); EC 3.6.1.- (Peptide Elongation Factor Tu); FYY3R43WGO (Minocycline); P88XT4IS4D (Paclitaxel)
[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:170625
[St] Status:MEDLINE


  5 / 1320 MEDLINE  
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[PMID]:28552981
[Au] Autor:Gzyl KE; Wieden HJ
[Ad] Endereço:Alberta RNA Research and Training Institute, Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, Alberta, Canada.
[Ti] Título:Tetracycline does not directly inhibit the function of bacterial elongation factor Tu.
[So] Source:PLoS One;12(5):e0178523, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Understanding the molecular mechanism of antibiotics that are currently in use is important for the development of new antimicrobials. The tetracyclines, discovered in the 1940s, are a well-established class of antibiotics that still have a role in treating microbial infections in humans. It is generally accepted that the main target of their action is the ribosome. The estimated affinity for tetracycline binding to the ribosome is relatively low compared to the actual potency of the drug in vivo. Therefore, additional inhibitory effects of tetracycline on the translation machinery have been discussed. Structural evidence suggests that tetracycline inhibits the function of the essential bacterial GTPase Elongation Factor (EF)-Tu through interaction with the bound nucleotide. Based on this, tetracycline has been predicted to impede the nucleotide-binding properties of EF-Tu. However, detailed kinetic studies addressing the effect of tetracycline on nucleotide binding have been prevented by the fluorescence properties of the antibiotic. Here, we report a fluorescence-based kinetic assay that minimizes the effect of tetracycline autofluorescence, enabling the detailed kinetic analysis of the nucleotide-binding properties of Escherichia coli EF-Tu. Furthermore, using physiologically relevant conditions, we demonstrate that tetracycline does not affect EF-Tu's intrinsic or ribosome-stimulated GTPase activity, nor the stability of the EF-Tu•GTP•Phe-tRNAPhe complex. We therefore provide clear evidence that tetracycline does not directly impede the function of EF-Tu.
[Mh] Termos MeSH primário: Bactérias/metabolismo
Fator Tu de Elongação de Peptídeos/antagonistas & inibidores
Tetraciclina/farmacologia
[Mh] Termos MeSH secundário: Cinética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
EC 3.6.1.- (Peptide Elongation Factor Tu); F8VB5M810T (Tetracycline)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170918
[Lr] Data última revisão:
170918
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170530
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0178523


  6 / 1320 MEDLINE  
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[PMID]:28538735
[Au] Autor:Loveland AB; Demo G; Grigorieff N; Korostelev AA
[Ad] Endereço:RNA Therapeutics Institute, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, Massachusetts 01605, USA.
[Ti] Título:Ensemble cryo-EM elucidates the mechanism of translation fidelity.
[So] Source:Nature;546(7656):113-117, 2017 06 01.
[Is] ISSN:1476-4687
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Gene translation depends on accurate decoding of mRNA, the structural mechanism of which remains poorly understood. Ribosomes decode mRNA codons by selecting cognate aminoacyl-tRNAs delivered by elongation factor Tu (EF-Tu). Here we present high-resolution structural ensembles of ribosomes with cognate or near-cognate aminoacyl-tRNAs delivered by EF-Tu. Both cognate and near-cognate tRNA anticodons explore the aminoacyl-tRNA-binding site (A site) of an open 30S subunit, while inactive EF-Tu is separated from the 50S subunit. A transient conformation of decoding-centre nucleotide G530 stabilizes the cognate codon-anticodon helix, initiating step-wise 'latching' of the decoding centre. The resulting closure of the 30S subunit docks EF-Tu at the sarcin-ricin loop of the 50S subunit, activating EF-Tu for GTP hydrolysis and enabling accommodation of the aminoacyl-tRNA. By contrast, near-cognate complexes fail to induce the G530 latch, thus favouring open 30S pre-accommodation intermediates with inactive EF-Tu. This work reveals long-sought structural differences between the pre-accommodation of cognate and near-cognate tRNAs that elucidate the mechanism of accurate decoding.
[Mh] Termos MeSH primário: Microscopia Crioeletrônica
Biossíntese de Proteínas
Ribossomos/metabolismo
Ribossomos/ultraestrutura
[Mh] Termos MeSH secundário: Anticódon/química
Anticódon/genética
Anticódon/ultraestrutura
Códon/química
Códon/genética
Códon/ultraestrutura
Escherichia coli/química
Escherichia coli/genética
Escherichia coli/ultraestrutura
GTP Fosfo-Hidrolases/metabolismo
GTP Fosfo-Hidrolases/ultraestrutura
Guanosina Trifosfato/metabolismo
Hidrólise
Modelos Moleculares
Fator Tu de Elongação de Peptídeos/metabolismo
Fator Tu de Elongação de Peptídeos/ultraestrutura
Domínios Proteicos
RNA Ribossômico 16S/genética
RNA Ribossômico 16S/metabolismo
RNA Ribossômico 16S/ultraestrutura
Aminoacil-RNA de Transferência/genética
Aminoacil-RNA de Transferência/metabolismo
Aminoacil-RNA de Transferência/ultraestrutura
Subunidades Ribossômicas/química
Subunidades Ribossômicas/metabolismo
Subunidades Ribossômicas/ultraestrutura
Ribossomos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anticodon); 0 (Codon); 0 (RNA, Ribosomal, 16S); 0 (RNA, Transfer, Amino Acyl); 86-01-1 (Guanosine Triphosphate); EC 3.6.1.- (GTP Phosphohydrolases); EC 3.6.1.- (Peptide Elongation Factor Tu)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171124
[Lr] Data última revisão:
171124
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170525
[St] Status:MEDLINE
[do] DOI:10.1038/nature22397


  7 / 1320 MEDLINE  
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[PMID]:28407488
[Au] Autor:Ding B; Zhang L; Li Z; Zhong Y; Tang Q; Qin Y; Chen M
[Ad] Endereço:State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, LuoJia Hill, Wuhan 430072, China.
[Ti] Título:The Matrix Protein of Human Parainfluenza Virus Type 3 Induces Mitophagy that Suppresses Interferon Responses.
[So] Source:Cell Host Microbe;21(4):538-547.e4, 2017 Apr 12.
[Is] ISSN:1934-6069
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Mitophagy is a form of autophagy that selectively removes damaged mitochondria. Impaired mitochondria can be tagged by the kinase PINK1, which triggers recruitment of the E3-ubiquitin ligase Parkin and subsequent mitochondrial sequestration within autophagosomes. We previously found that human parainfluenza virus type 3 (HPIV3) infection induces autophagy, but the type and mechanisms of autophagy induction remain unknown. Here, we show that matrix protein (M) of HPIV3 translocates to mitochondria and interacts with Tu translation elongation factor mitochondrial (TUFM). M-mediated mitophagy does not require the Parkin-PINK1 pathway but rather an interaction between M and the LC3 protein that mediates autophagosome formation. These interactions with both TUFM and LC3 are required for the induction of mitophagy and lead to inhibition of the type I interferon response. These results reveal that a viral protein is sufficient to induce mitophagy by bridging autophagosomes and mitochondria.
[Mh] Termos MeSH primário: Interações Hospedeiro-Patógeno
Imunossupressores/metabolismo
Interferons/secreção
Degradação Mitocondrial/efeitos dos fármacos
Vírus da Parainfluenza 3 Humana/patogenicidade
Fator Tu de Elongação de Peptídeos/metabolismo
Proteínas da Matriz Viral/metabolismo
[Mh] Termos MeSH secundário: Seres Humanos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Immunosuppressive Agents); 0 (Viral Matrix Proteins); 9008-11-1 (Interferons); EC 3.6.1.- (Peptide Elongation Factor Tu)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170428
[Lr] Data última revisão:
170428
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170414
[St] Status:MEDLINE


  8 / 1320 MEDLINE  
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[PMID]:28256783
[Au] Autor:Paulsson J; El Karoui M; Lindell M; Hughes D
[Ad] Endereço:Department of Systems Biology, Harvard University, Boston, MA, 02115, USA.
[Ti] Título:The processive kinetics of gene conversion in bacteria.
[So] Source:Mol Microbiol;104(5):752-760, 2017 Jun.
[Is] ISSN:1365-2958
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Gene conversion, non-reciprocal transfer from one homologous sequence to another, is a major force in evolutionary dynamics, promoting co-evolution in gene families and maintaining similarities between repeated genes. However, the properties of the transfer - where it initiates, how far it proceeds and how the resulting conversion tracts are affected by mismatch repair - are not well understood. Here, we use the duplicate tuf genes in Salmonella as a quantitatively tractable model system for gene conversion. We selected for conversion in multiple different positions of tuf, and examined the resulting distributions of conversion tracts in mismatch repair-deficient and mismatch repair-proficient strains. A simple stochastic model accounting for the essential steps of conversion showed excellent agreement with the data for all selection points using the same value of the conversion processivity, which is the only kinetic parameter of the model. The analysis suggests that gene conversion effectively initiates uniformly at any position within a tuf gene, and proceeds with an effectively uniform conversion processivity in either direction limited by the bounds of the gene.
[Mh] Termos MeSH primário: Bactérias/genética
Conversão Gênica
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Evolução Biológica
Reparo de Erro de Pareamento de DNA
Reparo do DNA
Cinética
Modelos Genéticos
Mutação
Fator Tu de Elongação de Peptídeos/genética
Salmonella/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); EC 3.6.1.- (Peptide Elongation Factor Tu)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171102
[Lr] Data última revisão:
171102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170304
[St] Status:MEDLINE
[do] DOI:10.1111/mmi.13661


  9 / 1320 MEDLINE  
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[PMID]:28233029
[Au] Autor:Kacar B; Ge X; Sanyal S; Gaucher EA
[Ad] Endereço:NASA Astrobiology Institute, Mountain View, CA, 94035, USA. kacar@fas.harvard.edu.
[Ti] Título:Experimental Evolution of Escherichia coli Harboring an Ancient Translation Protein.
[So] Source:J Mol Evol;84(2-3):69-84, 2017 Mar.
[Is] ISSN:1432-1432
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:The ability to design synthetic genes and engineer biological systems at the genome scale opens new means by which to characterize phenotypic states and the responses of biological systems to perturbations. One emerging method involves inserting artificial genes into bacterial genomes and examining how the genome and its new genes adapt to each other. Here we report the development and implementation of a modified approach to this method, in which phylogenetically inferred genes are inserted into a microbial genome, and laboratory evolution is then used to examine the adaptive potential of the resulting hybrid genome. Specifically, we engineered an approximately 700-million-year-old inferred ancestral variant of tufB, an essential gene encoding elongation factor Tu, and inserted it in a modern Escherichia coli genome in place of the native tufB gene. While the ancient homolog was not lethal to the cell, it did cause a twofold decrease in organismal fitness, mainly due to reduced protein dosage. We subsequently evolved replicate hybrid bacterial populations for 2000 generations in the laboratory and examined the adaptive response via fitness assays, whole genome sequencing, proteomics, and biochemical assays. Hybrid lineages exhibit a general adaptive strategy in which the fitness cost of the ancient gene was ameliorated in part by upregulation of protein production. Our results suggest that an ancient-modern recombinant method may pave the way for the synthesis of organisms that exhibit ancient phenotypes, and that laboratory evolution of these organisms may prove useful in elucidating insights into historical adaptive processes.
[Mh] Termos MeSH primário: Proteínas de Escherichia coli/genética
Escherichia coli/genética
Fator Tu de Elongação de Peptídeos/genética
Análise de Sequência/métodos
[Mh] Termos MeSH secundário: Evolução Biológica
DNA Antigo
Proteínas de Escherichia coli/metabolismo
Genes Bacterianos/genética
Genoma Bacteriano/genética
Óperon
Fator Tu de Elongação de Peptídeos/metabolismo
Alinhamento de Sequência/métodos
Análise de Sequência de Proteína/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Ancient); 0 (Escherichia coli Proteins); EC 3.6.1.- (Peptide Elongation Factor Tu); EC 3.6.1.- (tufB protein, E coli)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170530
[Lr] Data última revisão:
170530
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170225
[St] Status:MEDLINE
[do] DOI:10.1007/s00239-017-9781-0


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[PMID]:28130490
[Au] Autor:Sato A; Suematsu T; Aihara KK; Kita K; Suzuki T; Watanabe K; Ohtsuki T; Watanabe YI
[Ad] Endereço:Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
[Ti] Título:Duplication of mitochondrial EF-Tu: pre-adaptation to T-arm truncation and exclusion of bulky aminoacyl residues.
[So] Source:Biochem J;474(6):957-969, 2017 Mar 07.
[Is] ISSN:1470-8728
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Translation elongation factor Tu (EF-Tu) delivers aminoacyl-tRNA (aa-tRNA) to ribosomes in protein synthesis. EF-Tu generally recognizes aminoacyl moieties and acceptor- and T-stems of aa-tRNAs. However, nematode mitochondrial (mt) tRNAs frequently lack all or part of the T-arm that is recognized by canonical EF-Tu. We previously reported that two distinct EF-Tu species, EF-Tu1 and EF-Tu2, respectively, recognize mt tRNAs lacking T-arms and D-arms in the mitochondria of the chromadorean nematode EF-Tu2 specifically recognizes the seryl moiety of serylated D-armless tRNAs. Mitochondria of the enoplean nematode possess three structural types of tRNAs: T-armless tRNAs, D-armless tRNAs, and cloverleaf tRNAs with a short T-arm. mt EF-Tu1 binds to all three types and EF-Tu2 binds only to D-armless Ser-tRNAs, showing an evolutionary intermediate state from canonical EF-Tu to chromadorean nematode (e.g. ) EF-Tu species. We report here that two EF-Tu species also participate in mitochondria. Both EF-Tu1 and EF-Tu2 bound to cloverleaf and D-armless tRNAs. EF-Tu1 has the ability to recognize T-armless tRNAs that do not evidently exist in mitochondria, but do exist in related arthropod species. In addition, EF-Tu2 preferentially bound to aa-tRNAs carrying small amino acids, but not to aa-tRNAs carrying bulky amino acids. These results suggest that the mt translation system could be another intermediate state between the canonical and nematode mitochondria-type translation systems.
[Mh] Termos MeSH primário: Proteínas de Drosophila/química
Drosophila melanogaster/genética
Proteínas Mitocondriais/química
Fator Tu de Elongação de Peptídeos/química
Biossíntese de Proteínas
Aminoacil-RNA de Transferência/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
Evolução Biológica
Caenorhabditis elegans/genética
Caenorhabditis elegans/metabolismo
Clonagem Molecular
Proteínas de Drosophila/genética
Proteínas de Drosophila/metabolismo
Drosophila melanogaster/metabolismo
Escherichia coli/genética
Escherichia coli/metabolismo
Regulação da Expressão Gênica
Cinética
Mitocôndrias/genética
Mitocôndrias/metabolismo
Proteínas Mitocondriais/genética
Proteínas Mitocondriais/metabolismo
Conformação de Ácido Nucleico
Fator Tu de Elongação de Peptídeos/genética
Fator Tu de Elongação de Peptídeos/metabolismo
Isoformas de Proteínas/química
Isoformas de Proteínas/genética
Isoformas de Proteínas/metabolismo
Aminoacil-RNA de Transferência/genética
Aminoacil-RNA de Transferência/metabolismo
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Alinhamento de Sequência
Homologia de Sequência de Aminoácidos
Especificidade da Espécie
Trichinella/genética
Trichinella/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Drosophila Proteins); 0 (Mitochondrial Proteins); 0 (Protein Isoforms); 0 (RNA, Transfer, Amino Acyl); 0 (Recombinant Proteins); EC 3.6.1.- (Peptide Elongation Factor Tu)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170615
[Lr] Data última revisão:
170615
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170129
[St] Status:MEDLINE
[do] DOI:10.1042/BCJ20160929



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