Base de dados : MEDLINE
Pesquisa : D05.500.890 [Categoria DeCS]
Referências encontradas : 24 [refinar]
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[PMID]:28802041
[Au] Autor:Bausewein T; Mills DJ; Langer JD; Nitschke B; Nussberger S; Kühlbrandt W
[Ad] Endereço:Department of Structural Biology, Max-Planck-Institute of Biophysics, Max-von-Laue-Str. 3, 60438 Frankfurt am Main, Germany.
[Ti] Título:Cryo-EM Structure of the TOM Core Complex from Neurospora crassa.
[So] Source:Cell;170(4):693-700.e7, 2017 Aug 10.
[Is] ISSN:1097-4172
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The TOM complex is the main entry gate for protein precursors from the cytosol into mitochondria. We have determined the structure of the TOM core complex by cryoelectron microscopy (cryo-EM). The complex is a 148 kDa symmetrical dimer of ten membrane protein subunits that create a shallow funnel on the cytoplasmic membrane surface. In the core of the dimer, the ß-barrels of the Tom40 pore form two identical preprotein conduits. Each Tom40 pore is surrounded by the transmembrane segments of the α-helical subunits Tom5, Tom6, and Tom7. Tom22, the central preprotein receptor, connects the two Tom40 pores at the dimer interface. Our structure offers detailed insights into the molecular architecture of the mitochondrial preprotein import machinery.
[Mh] Termos MeSH primário: Proteínas de Transporte/química
Proteínas Fúngicas/química
Neurospora crassa/enzimologia
Sistemas de Translocação de Proteínas/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Transporte/genética
Proteínas de Transporte/ultraestrutura
Microscopia Crioeletrônica
Proteínas Fúngicas/genética
Proteínas Fúngicas/ultraestrutura
Espectrometria de Massas
Proteínas de Transporte da Membrana Mitocondrial/química
Proteínas de Transporte da Membrana Mitocondrial/genética
Proteínas de Transporte da Membrana Mitocondrial/ultraestrutura
Membranas Mitocondriais/enzimologia
Modelos Moleculares
Conformação Proteica em Folha beta
Sistemas de Translocação de Proteínas/genética
Sistemas de Translocação de Proteínas/ultraestrutura
Proteínas de Saccharomyces cerevisiae/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Carrier Proteins); 0 (Fungal Proteins); 0 (Mitochondrial Membrane Transport Proteins); 0 (Protein Translocation Systems); 0 (Saccharomyces cerevisiae Proteins); 0 (TOM translocase)
[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:170813
[St] Status:MEDLINE


  2 / 24 MEDLINE  
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[PMID]:28328943
[Au] Autor:Niesen MJ; Wang CY; Van Lehn RC; Miller TF
[Ad] Endereço:Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, United States of America.
[Ti] Título:Structurally detailed coarse-grained model for Sec-facilitated co-translational protein translocation and membrane integration.
[So] Source:PLoS Comput Biol;13(3):e1005427, 2017 Mar.
[Is] ISSN:1553-7358
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We present a coarse-grained simulation model that is capable of simulating the minute-timescale dynamics of protein translocation and membrane integration via the Sec translocon, while retaining sufficient chemical and structural detail to capture many of the sequence-specific interactions that drive these processes. The model includes accurate geometric representations of the ribosome and Sec translocon, obtained directly from experimental structures, and interactions parameterized from nearly 200 µs of residue-based coarse-grained molecular dynamics simulations. A protocol for mapping amino-acid sequences to coarse-grained beads enables the direct simulation of trajectories for the co-translational insertion of arbitrary polypeptide sequences into the Sec translocon. The model reproduces experimentally observed features of membrane protein integration, including the efficiency with which polypeptide domains integrate into the membrane, the variation in integration efficiency upon single amino-acid mutations, and the orientation of transmembrane domains. The central advantage of the model is that it connects sequence-level protein features to biological observables and timescales, enabling direct simulation for the mechanistic analysis of co-translational integration and for the engineering of membrane proteins with enhanced membrane integration efficiency.
[Mh] Termos MeSH primário: Bicamadas Lipídicas/química
Simulação de Dinâmica Molecular
Sistemas de Translocação de Proteínas/química
Sistemas de Translocação de Proteínas/ultraestrutura
Canais de Translocação SEC/química
Canais de Translocação SEC/ultraestrutura
[Mh] Termos MeSH secundário: Sítios de Ligação
Membrana Celular/química
Membrana Celular/ultraestrutura
Modelos Químicos
Movimento (Física)
Ligação Proteica
Conformação Proteica
Dobramento de Proteína
Transporte Proteico
Ribossomos/química
Ribossomos/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lipid Bilayers); 0 (Protein Translocation Systems); 0 (SEC Translocation Channels)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170619
[Lr] Data última revisão:
170619
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170323
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pcbi.1005427


  3 / 24 MEDLINE  
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[PMID]:28119513
[Au] Autor:Xu H; Denny TP
[Ad] Endereço:College of Plant Protection, Shandong Agricultural University, Tai'an, Shandong 271018, P.R. China.
[Ti] Título:Native and Foreign Proteins Secreted by the Type II System and an Alternative Mechanism.
[So] Source:J Microbiol Biotechnol;27(4):791-807, 2017 Apr 28.
[Is] ISSN:1738-8872
[Cp] País de publicação:Korea (South)
[La] Idioma:eng
[Ab] Resumo:The type II secretion system (T2SS), which transports selected periplasmic proteins across the outer membrane, has rarely been studied in nonpathogens or in organisms classified as Betaproteobacteria. Therefore, we studied ( ), a facultative chemilithoautotroph. Gel analysis of extracellular proteins revealed no remarkable differences between the wild type and the T2SS mutants. However, enzyme assays revealed that native extracellular alkaline phosphatase is a T2SS substrate, because activity was 10-fold greater for the wild type than a T2SS mutant. In engineered to produce three ( ) exoenzymes, at least 95% of their total activities were extracellular, but unexpectedly high percentages of these exoenzymes remained extracellular in T2SS mutants cultured in rich broth. These conditions appear to permit an alternative secretion process, because neither cell lysis nor periplasmic leakage was observed when produced a exoenzyme, and wild-type cultured in minimal medium secreted 98% of polygalacturonase, but 92% of this exoenzyme remained intracellular in T2SS mutants. We concluded that has a functional T2SS despite lacking any abundant native T2SS substrates. The efficient secretion of three foreign exoenzymes by is remarkable, but so too is the indication of an alternative secretion process in rich culture conditions. When not transiting the T2SS, we suggest that exoenzymes are probably selectively packaged into outer membrane vesicles. Phylogenetic analysis of T2SS proteins supports the existence of at least three T2SS subfamilies, and we propose that , as a representative of the Betaproteobacteria, could become a new useful model system for studying T2SS substrate specificity.
[Mh] Termos MeSH primário: Proteínas de Bactérias/secreção
Cupriavidus/enzimologia
Cupriavidus/metabolismo
Sistemas de Secreção Tipo II/metabolismo
Sistemas de Secreção Tipo II/fisiologia
[Mh] Termos MeSH secundário: Fosfatase Alcalina/genética
Fosfatase Alcalina/secreção
Sequência de Aminoácidos
Proteínas de Bactérias/genética
Transporte Biológico
Hidrolases de Éster Carboxílico/genética
Hidrolases de Éster Carboxílico/secreção
Celulase/genética
Celulase/secreção
Cupriavidus/genética
DNA Bacteriano
Ensaios Enzimáticos
Escherichia coli/genética
Regulação Bacteriana da Expressão Gênica
Genes Bacterianos
Família Multigênica/genética
Mutação
Pectobacterium carotovorum/enzimologia
Filogenia
Poligalacturonase/genética
Poligalacturonase/secreção
Domínios Proteicos
Estrutura Secundária de Proteína
Sistemas de Translocação de Proteínas/classificação
Sistemas de Translocação de Proteínas/genética
Sistemas de Translocação de Proteínas/metabolismo
Sistemas de Translocação de Proteínas/fisiologia
Ralstonia solanacearum/enzimologia
Alinhamento de Sequência
Sistemas de Secreção Tipo II/classificação
Sistemas de Secreção Tipo II/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (DNA, Bacterial); 0 (Protein Translocation Systems); 0 (Type II Secretion Systems); EC 3.1.1.- (Carboxylic Ester Hydrolases); EC 3.1.1.11 (pectinesterase); EC 3.1.3.1 (Alkaline Phosphatase); EC 3.2.1.15 (Polygalacturonase); EC 3.2.1.4 (Cellulase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171006
[Lr] Data última revisão:
171006
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170126
[St] Status:MEDLINE
[do] DOI:10.4014/jmb.1611.11002


  4 / 24 MEDLINE  
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[PMID]:28115202
[Au] Autor:Das D; Krantz BA
[Ad] Endereço:Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, 650 W. Baltimore Street, Baltimore, MD 21201, USA.
[Ti] Título:Secondary Structure Preferences of the Anthrax Toxin Protective Antigen Translocase.
[So] Source:J Mol Biol;429(5):753-762, 2017 Mar 10.
[Is] ISSN:1089-8638
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In order for many proteins to move across hydrophobic membrane bilayers, they must be unfolded and translocated by a membrane-embedded channel. These translocase channels interact with the substrate proteins they translocate via hydrophobic pore loops and cleft structures called clamps. The molecular basis for how clamps facilitate unfolding and translocation is poorly understood. Anthrax toxin is composed of three proteins, a translocase channel-forming subunit, called protective antigen (PA), and two substrate proteins, called lethal factor (LF) and edema factor. Oligomeric PA forms a large channel that contains three types of polypeptide clamp sites: an α clamp, a phenylalanine clamp, and a charge clamp. Currently, it is thought that these clamp sites operate allosterically and promote translocation via an allosteric helix compression mechanism. Here, we report on the substrate secondary structure dependence of the PA channel. Peptides derived from regions of LF with high α-helical content bound cooperatively, but those derived from ß-sheet regions in LF did not, suggesting that an allosteric site preferentially recognizes α-helical structure over ß-sheet structure. Peptides derived from helical sites in LF showed increasingly longer single-channel blockades as a function of peptide concentration, a result that was consistent with stronger clamping behavior and reduced backsliding. Moreover, peptides derived from helical regions of LF translocated more efficiently than peptides derived from ß-sheet regions of LF. Overall, in support of the allosteric helix compression model, we find that the channel prefers α-helical sequences over ß-sheet sequences.
[Mh] Termos MeSH primário: Antígenos de Bactérias/química
Bacillus anthracis/química
Toxinas Bacterianas/química
Canais Iônicos/química
Sistemas de Translocação de Proteínas/química
[Mh] Termos MeSH secundário: Concentração de Íons de Hidrogênio
Interações Hidrofóbicas e Hidrofílicas
Modelos Moleculares
Conformação Proteica em alfa-Hélice
Conformação Proteica em Folha beta
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antigens, Bacterial); 0 (Bacterial Toxins); 0 (Ion Channels); 0 (Protein Translocation Systems); 0 (anthrax toxin)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170731
[Lr] Data última revisão:
170731
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170125
[St] Status:MEDLINE


  5 / 24 MEDLINE  
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[PMID]:28019693
[Au] Autor:Scanlan E; Ardill L; Whelan MV; Shortt C; Nally JE; Bourke B; Ó Cróinín T
[Ad] Endereço:School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Dublin 4, Ireland.
[Ti] Título:Relaxation of DNA supercoiling leads to increased invasion of epithelial cells and protein secretion by Campylobacter jejuni.
[So] Source:Mol Microbiol;104(1):92-104, 2017 04.
[Is] ISSN:1365-2958
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Invasion of intestinal epithelial cells by Campylobacter jejuni is a critical step during infection of the intestine by this important human pathogen. In this study we investigated the role played by DNA supercoiling in the regulation of invasion of epithelial cells and the mechanism by which this could be mediated. A significant correlation between more relaxed DNA supercoiling and an increased ability of C. jejuni strains to penetrate human epithelial cells was demonstrated. Directly inducing relaxation of DNA supercoiling in C. jejuni was shown to significantly increase invasion of epithelial cells. Mutants in the fibronectin binding proteins CadF and FlpA still displayed an increased invasion after treatment with novobiocin suggesting these proteins were not essential for the observed phenotype. However, a large increase in protein secretion from multiple C. jejuni strains upon relaxation of DNA supercoiling was demonstrated. This increase in protein secretion was not mediated by outer membrane vesicles and appeared to be dependent on an intact flagellar structure. This study identifies relaxation of DNA supercoiling as playing a key role in enhancing C. jejuni pathogenesis during infection of the human intestine and identifies proteins present in a specific invasion associated secretome induced by relaxation of DNA supercoiling.
[Mh] Termos MeSH primário: Campylobacter jejuni/metabolismo
DNA Super-Helicoidal/genética
DNA Super-Helicoidal/metabolismo
[Mh] Termos MeSH secundário: Aderência Bacteriana/fisiologia
Proteínas da Membrana Bacteriana Externa/genética
Proteínas da Membrana Bacteriana Externa/metabolismo
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Infecções por Campylobacter/metabolismo
Infecções por Campylobacter/microbiologia
Campylobacter jejuni/genética
Proteínas de Transporte/genética
Proteínas de Transporte/metabolismo
Linhagem Celular
Movimento Celular/genética
DNA/metabolismo
Células Epiteliais/microbiologia
Fibronectinas/metabolismo
Seres Humanos
Intestinos/metabolismo
Novobiocina/metabolismo
Sistemas de Translocação de Proteínas
Transporte Proteico
Fatores de Transcrição/genética
Fatores de Transcrição/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Bacterial Proteins); 0 (CadF protein, Campylobacter jejuni); 0 (Carrier Proteins); 0 (DNA, Superhelical); 0 (Fibronectins); 0 (FlpA protein, bacteria); 0 (Protein Translocation Systems); 0 (Transcription Factors); 17EC19951N (Novobiocin); 9007-49-2 (DNA)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161227
[St] Status:MEDLINE
[do] DOI:10.1111/mmi.13614


  6 / 24 MEDLINE  
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[PMID]:27807044
[Au] Autor:Villeneuve J; Duran J; Scarpa M; Bassaganyas L; Van Galen J; Malhotra V
[Ad] Endereço:Cell and Developmental Biology Department, Centre for Genomic Regulation, Barcelona Institute for Science and Technology, 08003 Barcelona, Spain.
[Ti] Título:Golgi enzymes do not cycle through the endoplasmic reticulum during protein secretion or mitosis.
[So] Source:Mol Biol Cell;28(1):141-151, 2017 Jan 01.
[Is] ISSN:1939-4586
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Golgi-specific sialyltransferase (ST) expressed as a chimera with the rapamycin-binding domain of mTOR, FRB, relocates to the endoplasmic reticulum (ER) in cells exposed to rapamycin that also express invariant chain (Ii)-FKBP in the ER. This result has been taken to indicate that Golgi-resident enzymes cycle to the ER constitutively. We show that ST-FRB is trapped in the ER even without Ii-FKBP upon rapamycin addition. This is because ER-Golgi-cycling FKBP proteins contain a C-terminal KDEL-like sequence, bind ST-FRB in the Golgi, and are transported together back to the ER by KDEL receptor-mediated retrograde transport. Moreover, depletion of KDEL receptor prevents trapping of ST-FRB in the ER by rapamycin. Thus ST-FRB cycles artificially by binding to FKBP domain-containing proteins. In addition, Golgi-specific O-linked glycosylation of a resident ER protein occurs only upon artificial fusion of Golgi membranes with ER. Together these findings support the consensus view that there is no appreciable mixing of Golgi-resident enzymes with ER under normal conditions.
[Mh] Termos MeSH primário: Retículo Endoplasmático/metabolismo
Complexo de Golgi/metabolismo
Transporte Proteico/fisiologia
[Mh] Termos MeSH secundário: Animais
Transporte Biológico
Células COS
Cercopithecus aethiops
Complexo de Golgi/fisiologia
Células HeLa
Seres Humanos
Membranas Intracelulares/metabolismo
Mitose/fisiologia
Domínios Proteicos
Sistemas de Translocação de Proteínas
Receptores de Peptídeos/metabolismo
Sialiltransferases/metabolismo
Sirolimo
Serina-Treonina Quinases TOR
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (KDEL receptor); 0 (Protein Translocation Systems); 0 (Receptors, Peptide); EC 2.4.99.- (Sialyltransferases); EC 2.7.1.1 (TOR Serine-Threonine Kinases); W36ZG6FT64 (Sirolimus)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170921
[Lr] Data última revisão:
170921
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161104
[St] Status:MEDLINE
[do] DOI:10.1091/mbc.E16-08-0560


  7 / 24 MEDLINE  
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[PMID]:27550988
[Au] Autor:Kido K; Ato S; Yokokawa T; Makanae Y; Sato K; Fujita S
[Ad] Endereço:Faculty of Sport and Health Science, Ritsumeikan University, Kusatsu, Japan.
[Ti] Título:Acute resistance exercise-induced IGF1 expression and subsequent GLUT4 translocation.
[So] Source:Physiol Rep;4(16), 2016 Aug.
[Is] ISSN:2051-817X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Acute aerobic exercise (AE) is a major physiological stimulus for skeletal muscle glucose uptake through activation of 5' AMP-activated protein kinase (AMPK). However, the regulation of glucose uptake by acute resistance exercise (RE) remains unclear. To investigate the intracellular regulation of glucose uptake after acute RE versus acute AE, male Sprague-Dawley rats were divided into three groups: RE, AE, or nonexercise control. After fasting for 12 h overnight, the right gastrocnemius muscle in the RE group was exercised at maximum isometric contraction via percutaneous electrical stimulation (3 × 10 sec, 5 sets). The AE group ran on a treadmill (25 m/min, 60 min). Muscle samples were taken 0, 1, and 3 h after completion of the exercises. AMPK, Ca(2+)/calmodulin-dependent protein kinase II, and TBC1D1 phosphorylation were increased immediately after both forms of exercise and returned to baseline levels by 3 h. Muscle IGF1 expression was increased by RE but not AE, and maintained until 3 h after RE Additionally, Akt and AS160 phosphorylation were sustained for 3 h after RE, whereas they returned to baseline levels by 3 h after AE Similarly, GLUT4 translocation remained elevated 3 h after RE, although it returned to the baseline level by 3 h after AE Overall, this study showed that AMPK/TBC1D1 and IGF1/Akt/AS160 signaling were enhanced by acute RE, and that GLUT4 translocation after acute RE was more prolonged than after acute AE These results suggest that acute RE-induced increases in intramuscular IGF1 expression might be a distinct regulator of GLUT4 translocation.
[Mh] Termos MeSH primário: Anormalidades Múltiplas/metabolismo
Transportador de Glucose Tipo 4/genética
Transtornos do Crescimento/metabolismo
Músculo Esquelético/metabolismo
Condicionamento Físico Animal/fisiologia
Sistemas de Translocação de Proteínas/metabolismo
[Mh] Termos MeSH secundário: Proteínas Quinases Ativadas por AMP/metabolismo
Animais
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo
Proteínas Ativadoras de GTPase/metabolismo
Glucose/análise
Glucose/metabolismo
Fator de Crescimento Insulin-Like I/metabolismo
Masculino
Músculo Esquelético/citologia
Fosforilação/genética
Fosforilação/fisiologia
Condicionamento Físico Animal/efeitos adversos
Proteínas/metabolismo
Ratos
Ratos Sprague-Dawley
Transdução de Sinais/fisiologia
Estimulação Elétrica Nervosa Transcutânea/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (GTPase-Activating Proteins); 0 (Glucose Transporter Type 4); 0 (LOC686547 protein, rat); 0 (Protein Translocation Systems); 0 (Proteins); 0 (TBC1D1 protein, rat); 0 (insulin-like growth factor-1, rat); 67763-96-6 (Insulin-Like Growth Factor I); EC 2.7.11.17 (Calcium-Calmodulin-Dependent Protein Kinase Type 2); EC 2.7.11.31 (AMP-Activated Protein Kinases); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160824
[St] Status:MEDLINE


  8 / 24 MEDLINE  
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[PMID]:27446813
[Au] Autor:Amer AA; Gurung JM; Costa TR; Ruuth K; Zavialov AV; Forsberg Å; Francis MS
[Ad] Endereço:Department of Molecular Biology, Umeå UniversityUmeå, Sweden; Umeå Centre for Microbial Research, Umeå UniversityUmeå, Sweden.
[Ti] Título:YopN and TyeA Hydrophobic Contacts Required for Regulating Ysc-Yop Type III Secretion Activity by Yersinia pseudotuberculosis.
[So] Source:Front Cell Infect Microbiol;6:66, 2016.
[Is] ISSN:2235-2988
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Yersinia bacteria target Yop effector toxins to the interior of host immune cells by the Ysc-Yop type III secretion system. A YopN-TyeA heterodimer is central to controlling Ysc-Yop targeting activity. A + 1 frameshift event in the 3-prime end of yopN can also produce a singular secreted YopN-TyeA polypeptide that retains some regulatory function even though the C-terminal coding sequence of this YopN differs greatly from wild type. Thus, this YopN C-terminal segment was analyzed for its role in type III secretion control. Bacteria producing YopN truncated after residue 278, or with altered sequence between residues 279 and 287, had lost type III secretion control and function. In contrast, YopN variants with manipulated sequence beyond residue 287 maintained full control and function. Scrutiny of the YopN-TyeA complex structure revealed that residue W279 functioned as a likely hydrophobic contact site with TyeA. Indeed, a YopN W279G mutant lost all ability to bind TyeA. The TyeA residue F8 was also critical for reciprocal YopN binding. Thus, we conclude that specific hydrophobic contacts between opposing YopN and TyeA termini establishes a complex needed for regulating Ysc-Yop activity.
[Mh] Termos MeSH primário: Proteínas da Membrana Bacteriana Externa/química
Proteínas de Bactérias/química
Proteínas de Transporte/química
Interações Hidrofóbicas e Hidrofílicas
Proteínas de Membrana/química
Domínios e Motivos de Interação entre Proteínas
Sistemas de Secreção Tipo III/secreção
Yersinia pseudotuberculosis/metabolismo
[Mh] Termos MeSH secundário: Animais
Proteínas da Membrana Bacteriana Externa/genética
Proteínas de Bactérias/genética
Proteínas de Bactérias/secreção
Transporte Biológico
Cálcio/química
Proteínas de Transporte/genética
Linhagem Celular
DNA Bacteriano
Regulação Bacteriana da Expressão Gênica
Genes Bacterianos/genética
Macrófagos/microbiologia
Proteínas de Membrana/genética
Camundongos
Modelos Moleculares
Mutagênese Sítio-Dirigida
Estabilidade Proteica
Sistemas de Translocação de Proteínas
Análise de Sequência
Deleção de Sequência
Temperatura Ambiente
Técnicas do Sistema de Duplo-Híbrido
Sistemas de Secreção Tipo III/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Bacterial Proteins); 0 (Carrier Proteins); 0 (DNA, Bacterial); 0 (Membrane Proteins); 0 (Protein Translocation Systems); 0 (TyeA protein, Yersinia); 0 (Type III Secretion Systems); 138341-76-1 (YopN protein, Yersinia); SY7Q814VUP (Calcium)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160723
[St] Status:MEDLINE
[do] DOI:10.3389/fcimb.2016.00066


  9 / 24 MEDLINE  
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[PMID]:27374802
[Au] Autor:de Koning-Ward TF; Dixon MW; Tilley L; Gilson PR
[Ad] Endereço:School of Medicine, Deakin University, Waurn Ponds, Victoria 3216, Australia.
[Ti] Título:Plasmodium species: master renovators of their host cells.
[So] Source:Nat Rev Microbiol;14(8):494-507, 2016 08.
[Is] ISSN:1740-1534
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Plasmodium parasites, the causative agents of malaria, have developed elaborate strategies that they use to survive and thrive within different intracellular environments. During the blood stage of infection, the parasite is a master renovator of its erythrocyte host cell, and the changes in cell morphology and function that are induced by the parasite promote survival and contribute to the pathogenesis of severe malaria. In this Review, we discuss how Plasmodium parasites use the protein trafficking motif Plasmodium export element (PEXEL), protease-mediated polypeptide processing, a novel translocon termed the Plasmodium translocon of exported proteins (PTEX) and exomembranous structures to export hundreds of proteins to discrete subcellular locations in the host erythrocytes, which enables the parasite to gain access to vital nutrients and to evade the immune defence mechanisms of the host.
[Mh] Termos MeSH primário: Eritrócitos/parasitologia
Interações Hospedeiro-Patógeno
Malária Falciparum/parasitologia
Malária/parasitologia
Plasmodium falciparum/fisiologia
Transporte Proteico
Proteínas de Protozoários/metabolismo
[Mh] Termos MeSH secundário: Motivos de Aminoácidos
Animais
Eritrócitos/fisiologia
Seres Humanos
Evasão da Resposta Imune
Plasmodium berghei/genética
Plasmodium berghei/patogenicidade
Plasmodium berghei/fisiologia
Plasmodium falciparum/genética
Plasmodium falciparum/patogenicidade
Sinais Direcionadores de Proteínas
Sistemas de Translocação de Proteínas/metabolismo
Proteínas de Protozoários/química
Proteínas de Protozoários/genética
Vesículas Transportadoras
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Protein Sorting Signals); 0 (Protein Translocation Systems); 0 (Protozoan Proteins)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170606
[Lr] Data última revisão:
170606
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160705
[St] Status:MEDLINE
[do] DOI:10.1038/nrmicro.2016.79


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[PMID]:27313204
[Au] Autor:Chen C; Cui X; Beausang JF; Zhang H; Farrell I; Cooperman BS; Goldman YE
[Ad] Endereço:Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6085; Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6083;
[Ti] Título:Elongation factor G initiates translocation through a power stroke.
[So] Source:Proc Natl Acad Sci U S A;113(27):7515-20, 2016 07 05.
[Is] ISSN:1091-6490
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:During the translocation step of prokaryotic protein synthesis, elongation factor G (EF-G), a guanosine triphosphatase (GTPase), binds to the ribosomal PRE-translocation (PRE) complex and facilitates movement of transfer RNAs (tRNAs) and messenger RNA (mRNA) by one codon. Energy liberated by EF-G's GTPase activity is necessary for EF-G to catalyze rapid and precise translocation. Whether this energy is used mainly to drive movements of the tRNAs and mRNA or to foster EF-G dissociation from the ribosome after translocation has been a long-lasting debate. Free EF-G, not bound to the ribosome, adopts quite different structures in its GTP and GDP forms. Structures of EF-G on the ribosome have been visualized at various intermediate steps along the translocation pathway, using antibiotics and nonhydolyzable GTP analogs to block translocation and to prolong the dwell time of EF-G on the ribosome. However, the structural dynamics of EF-G bound to the ribosome have not yet been described during normal, uninhibited translocation. Here, we report the rotational motions of EF-G domains during normal translocation detected by single-molecule polarized total internal reflection fluorescence (polTIRF) microscopy. Our study shows that EF-G has a small (∼10°) global rotational motion relative to the ribosome after GTP hydrolysis that exerts a force to unlock the ribosome. This is followed by a larger rotation within domain III of EF-G before its dissociation from the ribosome.
[Mh] Termos MeSH primário: Guanosina Trifosfato/metabolismo
Fator G para Elongação de Peptídeos/metabolismo
Ribossomos/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Dados de Sequência Molecular
Sistemas de Translocação de Proteínas
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Peptide Elongation Factor G); 0 (Protein Translocation Systems); 86-01-1 (Guanosine Triphosphate)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170724
[Lr] Data última revisão:
170724
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160618
[St] Status:MEDLINE
[do] DOI:10.1073/pnas.1602668113



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