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Pesquisa : A11.284.149 [Categoria DeCS]
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  1 / 162429 MEDLINE  
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[PMID]:29346419
[Au] Autor:Holcomb J; Doughan M; Spellmon N; Lewis B; Perry E; Zhang Y; Nico L; Wan J; Chakravarthy S; Shang W; Miao Q; Stemmler T; Yang Z
[Ad] Endereço:Department of Biochemistry and Molecular Biology, Wayne State University School of Medicine, Detroit, Michigan, United States of America.
[Ti] Título:SAXS analysis of a soluble cytosolic NgBR construct including extracellular and transmembrane domains.
[So] Source:PLoS One;13(1):e0191371, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The Nogo-B receptor (NgBR) is involved in oncogenic Ras signaling through directly binding to farnesylated Ras. It recruits farnesylated Ras to the non-lipid-raft membrane for interaction with downstream effectors. However, the cytosolic domain of NgBR itself is only partially folded. The lack of several conserved secondary structural elements makes this domain unlikely to form a complete farnesyl binding pocket. We find that inclusion of the extracellular and transmembrane domains that contain additional conserved residues to the cytosolic region results in a well folded protein with a similar size and shape to the E.coli cis-isoprenyl transferase (UPPs). Small Angle X-ray Scattering (SAXS) analysis reveals the radius of gyration (Rg) of our NgBR construct to be 18.2 Å with a maximum particle dimension (Dmax) of 61.0 Å. Ab initio shape modeling returns a globular molecular envelope with an estimated molecular weight of 23.0 kD closely correlated with the calculated molecular weight. Both Kratky plot and pair distribution function of NgBR scattering reveal a bell shaped peak which is characteristic of a single globularly folded protein. In addition, circular dichroism (CD) analysis reveals that our construct has the secondary structure contents similar to the UPPs. However, this result does not agree with the currently accepted topological orientation of NgBR which might partition this construct into three separate domains. This discrepancy suggests another possible NgBR topology and lends insight into a potential molecular basis of how NgBR facilitates farnesylated Ras recruitment.
[Mh] Termos MeSH primário: Receptores de Superfície Celular/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Sítios de Ligação
Membrana Celular/metabolismo
Dicroísmo Circular
Citosol/metabolismo
Peso Molecular
Estrutura Secundária de Proteína
Receptores de Superfície Celular/metabolismo
Espalhamento a Baixo Ângulo
Homologia de Sequência de Aminoácidos
Solubilidade
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (NUS1 protein, human); 0 (Receptors, Cell Surface)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180119
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191371


  2 / 162429 MEDLINE  
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[PMID]:29402931
[Au] Autor:Bianchi F; Syga L; Moiset G; Spakman D; Schavemaker PE; Punter CM; Seinen AB; van Oijen AM; Robinson A; Poolman B
[Ad] Endereço:Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9700AB, Groningen, The Netherlands.
[Ti] Título:Steric exclusion and protein conformation determine the localization of plasma membrane transporters.
[So] Source:Nat Commun;9(1):501, 2018 02 05.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The plasma membrane (PM) of Saccharomyces cerevisiae contains membrane compartments, MCC/eisosomes and MCPs, named after the protein residents Can1 and Pma1, respectively. Using high-resolution fluorescence microscopy techniques we show that Can1 and the homologous transporter Lyp1 are able to diffuse into the MCC/eisosomes, where a limited number of proteins are conditionally trapped at the (outer) edge of the compartment. Upon addition of substrate, the immobilized proteins diffuse away from the MCC/eisosomes, presumably after taking a different conformation in the substrate-bound state. Our data indicate that the mobile fraction of all integral plasma membrane proteins tested shows extremely slow Brownian diffusion through most of the PM. We also show that proteins with large cytoplasmic domains, such as Pma1 and synthetic chimera of Can1 and Lyp1, are excluded from the MCC/eisosomes. We hypothesize that the distinct localization patterns found for these integral membrane proteins in S. cerevisiae arises from a combination of slow lateral diffusion, steric exclusion, and conditional trapping in membrane compartments.
[Mh] Termos MeSH primário: Sistemas de Transporte de Aminoácidos Básicos/química
Membrana Celular/metabolismo
ATPases Translocadoras de Prótons/química
Proteínas de Saccharomyces cerevisiae/química
Saccharomyces cerevisiae/metabolismo
[Mh] Termos MeSH secundário: Sistemas de Transporte de Aminoácidos Básicos/metabolismo
Membrana Celular/ultraestrutura
Difusão
Recuperação de Fluorescência Após Fotodegradação
Cinética
Microdomínios da Membrana
Conformação Proteica
Transporte Proteico
ATPases Translocadoras de Prótons/metabolismo
Saccharomyces cerevisiae/ultraestrutura
Proteínas de Saccharomyces cerevisiae/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Amino Acid Transport Systems, Basic); 0 (CAN1 protein, S cerevisiae); 0 (LYP1 protein, S cerevisiae); 0 (Saccharomyces cerevisiae Proteins); EC 3.6.1.- (PMA1 protein, S cerevisiae); EC 3.6.3.14 (Proton-Translocating ATPases)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180307
[Lr] Data última revisão:
180307
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180207
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-018-02864-2


  3 / 162429 MEDLINE  
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[PMID]:28452328
[Au] Autor:Golafshan N; Gharibi H; Kharaziha M; Fathi M
[Ad] Endereço:Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
[Ti] Título:A facile one-step strategy for development of a double network fibrous scaffold for nerve tissue engineering.
[So] Source:Biofabrication;9(2):025008, 2017 04 28.
[Is] ISSN:1758-5090
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The aim of this study was to develop a novel double network scaffold composed of polycaprolactone fumarate (PCLF) and eggshell membrane (ESM) (ESM:PCLF) by using the vacuum infiltration method. Compared to ESM, the mechanical properties of double network scaffold were significantly improved, depending on the solvents applied for double network scaffold formation; acetic acid and dichloromethane. Noticeably, the toughness and strength of double network scaffold prepared using acetic acid were significantly improved compared to ESM (26.6 and 25 times, respectively) attributed to the existence of hydrophilic functional groups in acetic acid which made ESM flexible to absorb further PCLF solution. To assess the effect of double network formation on the biological behavior of ESM, the attachment, proliferation and spreading of PC12 cells cultured on the ESM:PCLF scaffolds were evaluated. Results revealed that the number of cells attached on double network ESM:PCLF scaffold were nearly similar to ESM and significantly higher than that of on the tissue culture plate (2.6 times) and PCLF film (1.7 times). It is envisioned that the offered ESM:PCLF double network scaffold might have great potential to develop the constructs for nerve regeneration.
[Mh] Termos MeSH primário: Tecido Nervoso/fisiologia
Engenharia Tecidual
Tecidos Suporte/química
[Mh] Termos MeSH secundário: Animais
Materiais Biocompatíveis/síntese química
Materiais Biocompatíveis/química
Materiais Biocompatíveis/farmacologia
Membrana Celular/química
Movimento Celular/efeitos dos fármacos
Proliferação Celular/efeitos dos fármacos
Sobrevivência Celular/efeitos dos fármacos
Casca de Ovo
Interações Hidrofóbicas e Hidrofílicas
Microscopia Eletrônica de Varredura
Regeneração Nervosa/efeitos dos fármacos
Células PC12
Poliésteres/química
Ratos
Espectroscopia de Infravermelho com Transformada de Fourier
Raios Ultravioleta
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biocompatible Materials); 0 (Polyesters); 0 (poly(caprolactone fumarate))
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1088/1758-5090/aa68ed


  4 / 162429 MEDLINE  
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[PMID]:29416037
[Au] Autor:Zabara A; Chong JTY; Martiel I; Stark L; Cromer BA; Speziale C; Drummond CJ; Mezzenga R
[Ad] Endereço:Department of Health Sciences and Technology, ETH Zurich, Schmelzbergstrasse 9 LFO E23, 8092, Zürich, Switzerland.
[Ti] Título:Design of ultra-swollen lipidic mesophases for the crystallization of membrane proteins with large extracellular domains.
[So] Source:Nat Commun;9(1):544, 2018 02 07.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In meso crystallization of membrane proteins from lipidic mesophases is central to protein structural biology but limited to membrane proteins with small extracellular domains (ECDs), comparable to the water channels (3-5 nm) of the mesophase. Here we present a strategy expanding the scope of in meso crystallization to membrane proteins with very large ECDs. We combine monoacylglycerols and phospholipids to design thermodynamically stable ultra-swollen bicontinuous cubic phases of double-gyroid (Ia3d), double-diamond (Pn3m), and double-primitive (Im3m) space groups, with water channels five times larger than traditional lipidic mesophases, and showing re-entrant behavior upon increasing hydration, of sequences Ia3d→Pn3m→Ia3d and Pn3m→Im3m→Pn3m, unknown in lipid self-assembly. We use these mesophases to crystallize membrane proteins with ECDs inaccessible to conventional in meso crystallization, demonstrating the methodology on the Gloeobacter ligand-gated ion channel (GLIC) protein, and show substantial modulation of packing, molecular contacts and activation state of the ensued proteins crystals, illuminating a general strategy in protein structural biology.
[Mh] Termos MeSH primário: Membrana Celular
Proteínas de Membrana/química
Fosfatidilgliceróis/química
[Mh] Termos MeSH secundário: Cristalização/métodos
Ácidos Graxos Monoinsaturados/química
Canais Iônicos
Transição de Fase
Domínios Proteicos
Termodinâmica
Água
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Fatty Acids, Monounsaturated); 0 (Ion Channels); 0 (Membrane Proteins); 0 (Phosphatidylglycerols); 059QF0KO0R (Water); 4271ZA8WXO (distearoyl phosphatidylglycerol)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180209
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-018-02996-5


  5 / 162429 MEDLINE  
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[PMID]:29407462
[Au] Autor:Zambrano P; Suwalsky M; Jemiola-Rzeminska M; Strzalka K
[Ad] Endereço:Faculty of Chemical Sciences, University of Concepción, Concepción, Chile. Electronic address: pzambranol@udec.cl.
[Ti] Título:Studies on the interaction of NMDA receptor antagonist memantine with cell membranes: A mini-review.
[So] Source:Chem Biol Interact;283:47-50, 2018 Mar 01.
[Is] ISSN:1872-7786
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:Memantine is an NMDA receptor antagonist clinically used for the treatment of moderate to severe Alzheimer's disease. Currently, it is the only NMDA receptor antagonist drug marketed against this disease. Despite the large number of publications regarding its clinical and therapeutic use, studies related to its mechanism of action are still inconclusive. Knowledge of drug interactions with cell membranes may lead to the development of novel drugs for neurodegenerative diseases. The present mini-review aims to give an overview of the latest findings regarding the interaction of memantine with cell membranes, specifically with that of the human erythrocyte.
[Mh] Termos MeSH primário: Membrana Celular/efeitos dos fármacos
Memantina/farmacologia
Receptores de N-Metil-D-Aspartato/antagonistas & inibidores
[Mh] Termos MeSH secundário: Doença de Alzheimer/tratamento farmacológico
Doença de Alzheimer/metabolismo
Doença de Alzheimer/patologia
Membrana Celular/metabolismo
Eritrócitos/citologia
Eritrócitos/efeitos dos fármacos
Eritrócitos/metabolismo
Seres Humanos
Memantina/química
Memantina/uso terapêutico
Microscopia Eletrônica de Varredura
Receptores de N-Metil-D-Aspartato/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Receptors, N-Methyl-D-Aspartate); W8O17SJF3T (Memantine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180207
[St] Status:MEDLINE


  6 / 162429 MEDLINE  
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[PMID]:29378162
[Au] Autor:Vila L; García-Rodríguez A; Cortés C; Velázquez A; Xamena N; Sampayo-Reyes A; Marcos R; Hernández A
[Ad] Endereço:Grup de Mutagènesi, Departament de Genètica i de Microbiologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, Spain.
[Ti] Título:Effects of cerium oxide nanoparticles on differentiated/undifferentiated human intestinal Caco-2 cells.
[So] Source:Chem Biol Interact;283:38-46, 2018 Mar 01.
[Is] ISSN:1872-7786
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:Since ingestion constitute one of the main routes of nanoparticles (NPs) exposure, intestinal cells seems to be a suitable choice to evaluate their potential harmful effects. Caco-2 cells, derived from a human colon adenocarcinoma, have the ability to differentiate forming consistent cell monolayer structures. For these reasons Caco-2 cells, both in their undifferentiated or differentiated state, are extendedly used. We have used well-structured monolayers of differentiated Caco-2 cells, as a model of intestinal barrier, to evaluate potential harmful effects associated to CeO NPs exposure via ingestion. Different parameters such as cell toxicity, monolayer integrity and permeability, cell internalization, translocation through the monolayer, and induction of DNA damage were evaluated. No toxic effects of CeO NPs were observed, independently of the differentiated state of the Caco-2 cells. In the same way, no effects on the monolayer integrity/permeability were observed. Although important cell uptake was demonstrated in undifferentiated cells (by using confocal microscopy), CeO NPs remained mostly attached to the apical membrane in the differentiated cells. In spite of this apparent lack of uptake in differentiated cells, translocation of CeO NPs to the basolateral chamber was observed by using confocal microscopy. Finally no genotoxic effects were observed when the comet assay was used, although decreases in the levels of oxidized bases were observed, supporting the antioxidant role of CeO NPs.
[Mh] Termos MeSH primário: Diferenciação Celular/efeitos dos fármacos
Cério/química
Nanopartículas Metálicas/toxicidade
[Mh] Termos MeSH secundário: Células CACO-2
Membrana Celular/efeitos dos fármacos
Membrana Celular/metabolismo
Permeabilidade da Membrana Celular/efeitos dos fármacos
Sobrevivência Celular/efeitos dos fármacos
Dano ao DNA/efeitos dos fármacos
Seres Humanos
Intestinos/citologia
Intestinos/metabolismo
Nanopartículas Metálicas/química
Microscopia Confocal
Tamanho da Partícula
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
30K4522N6T (Cerium); 619G5K328Y (ceric oxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180130
[St] Status:MEDLINE


  7 / 162429 MEDLINE  
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[PMID]:29362354
[Au] Autor:Garcia-Alai MM; Heidemann J; Skruzny M; Gieras A; Mertens HDT; Svergun DI; Kaksonen M; Uetrecht C; Meijers R
[Ad] Endereço:European Molecular Biology Laboratory (EMBL), Hamburg Outstation, Notkestrasse 85, 22607, Hamburg, Germany.
[Ti] Título:Epsin and Sla2 form assemblies through phospholipid interfaces.
[So] Source:Nat Commun;9(1):328, 2018 01 23.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In clathrin-mediated endocytosis, adapter proteins assemble together with clathrin through interactions with specific lipids on the plasma membrane. However, the precise mechanism of adapter protein assembly at the cell membrane is still unknown. Here, we show that the membrane-proximal domains ENTH of epsin and ANTH of Sla2 form complexes through phosphatidylinositol 4,5-bisphosphate (PIP2) lipid interfaces. Native mass spectrometry reveals how ENTH and ANTH domains form assemblies by sharing PIP2 molecules. Furthermore, crystal structures of epsin Ent2 ENTH domain from S. cerevisiae in complex with PIP2 and Sla2 ANTH domain from C. thermophilum illustrate how allosteric phospholipid binding occurs. A comparison with human ENTH and ANTH domains reveal only the human ENTH domain can form a stable hexameric core in presence of PIP2, which could explain functional differences between fungal and human epsins. We propose a general phospholipid-driven multifaceted assembly mechanism tolerating different adapter protein compositions to induce endocytosis.
[Mh] Termos MeSH primário: Proteínas Adaptadoras de Transporte Vesicular/química
Proteínas Fúngicas/química
Fosfatidilinositol 4,5-Difosfato/química
Domínios Proteicos
[Mh] Termos MeSH secundário: Proteínas Adaptadoras de Transporte Vesicular/genética
Proteínas Adaptadoras de Transporte Vesicular/metabolismo
Sequência de Aminoácidos
Sítios de Ligação/genética
Membrana Celular/metabolismo
Chaetomium/genética
Chaetomium/metabolismo
Cristalografia por Raios X
Endocitose
Proteínas Fúngicas/genética
Proteínas Fúngicas/metabolismo
Seres Humanos
Modelos Moleculares
Fosfatidilinositol 4,5-Difosfato/metabolismo
Ligação Proteica
Multimerização Proteica
Saccharomyces cerevisiae/genética
Saccharomyces cerevisiae/metabolismo
Homologia de Sequência de Aminoácidos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Adaptor Proteins, Vesicular Transport); 0 (Fungal Proteins); 0 (Phosphatidylinositol 4,5-Diphosphate); 0 (epsin)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180125
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02443-x


  8 / 162429 MEDLINE  
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[PMID]:29329092
[Au] Autor:Tian Z; Pang H; Zhang Q; Du S; Lu Y; Zhang L; Bai J; Li P; Li D; Zhao M; Chen X
[Ad] Endereço:School of Chinese Materia Medica, Beijing University of Chinese Medicine, 6#, WangjingZhonghuanNanlu, Chaoyang District, Beijing 100102, China; School of Pharmaceutical Science, Tsinghua University, Shuangqinglu, Beijing, China.
[Ti] Título:Effect of aspirin on the pharmacokinetics and absorption of panax notoginseng saponins.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1074-1075:25-33, 2018 Feb 01.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Panax notoginseng saponins, a traditional Chinese medicine extraction, and aspirin are both widely used to treat cerebral infarction in China. Good results in clinical practice have been achieved, when Panax notoginseng saponins was taken together with aspirin. METHODS: To investigate the interaction of the two drugs in vivo, the concentration of notoginsenoside R , ginsenoside Rg , Rb , Re and Rd. in blood were simultaneously measured by UPLC/MS/MS. Sample preparation was carried out by the protein precipitation technique with an internal standard saikosaponin A standard. The separation of six components was achieved by using an ACQUITY UPLC ®BEH C18 column (1.7µm 2.1×100mm) by gradient elution using water (containing 0.2% formic acid) and acetonitrile (containing 0.2% formic acid) as the mobile phase at a flow rate of 0.2mL/min. The pharmacokinetic parameters were determined using non-compartmental analysis. The transport of notoginsenoside R , ginsenoside Rg , Rb , Re and Rd. in MDCK -MDR1 cell monolayer was also used to verify the conclusion of pharmacokinetic drug-drug interaction and study the mechanism of drug interaction. RESULTS: The concentrations of the five components increased in a certain extent when the two drugs administered together in rats. The values of apparent permeability coefficients were significantly increased when the two drugs were used together. Aspirin and salicylic acid could destroy the tight junction protein and open the intercellular space to increase the absorption of Panax notoginseng saponins. CONCLUSION: Pharmacokinetic drug-drug interaction in vivo existed between Panax notoginseng saponins and aspirin. The drug-drug interaction mainly occurred in the process of absorption.
[Mh] Termos MeSH primário: Aspirina/farmacocinética
Medicamentos de Ervas Chinesas/farmacocinética
Panax notoginseng/química
Saponinas/sangue
Saponinas/farmacocinética
[Mh] Termos MeSH secundário: Animais
Aspirina/farmacologia
Membrana Celular/efeitos dos fármacos
Cães
Medicamentos de Ervas Chinesas/farmacologia
Interações Ervas-Drogas
Limite de Detecção
Modelos Lineares
Células Madin Darby de Rim Canino
Ratos
Ratos Sprague-Dawley
Reprodutibilidade dos Testes
Saponinas/química
Saponinas/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Drugs, Chinese Herbal); 0 (Saponins); R16CO5Y76E (Aspirin)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180113
[St] Status:MEDLINE


  9 / 162429 MEDLINE  
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[PMID]:29323112
[Au] Autor:Pflüger T; Hernández CF; Lewe P; Frank F; Mertens H; Svergun D; Baumstark MW; Lunin VY; Jetten MSM; Andrade SLA
[Ad] Endereço:Institute for Biochemistry, University of Freiburg, Albertstr. 21, Freiburg, 79104, Germany.
[Ti] Título:Signaling ammonium across membranes through an ammonium sensor histidine kinase.
[So] Source:Nat Commun;9(1):164, 2018 01 11.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Sensing and uptake of external ammonium is essential for anaerobic ammonium-oxidizing (anammox) bacteria, and is typically the domain of the ubiquitous Amt/Rh ammonium transporters. Here, we report on the structure and function of an ammonium sensor/transducer from the anammox bacterium "Candidatus Kuenenia stuttgartiensis" that combines a membrane-integral ammonium transporter domain with a fused histidine kinase. It contains a high-affinity ammonium binding site not present in assimilatory Amt proteins. The levels of phosphorylated histidine in the kinase are coupled to the presence of ammonium, as conformational changes during signal recognition by the Amt module are transduced internally to modulate the kinase activity. The structural analysis of this ammonium sensor by X-ray crystallography and small-angle X-ray-scattering reveals a flexible, bipartite system that recruits a large uptake transporter as a sensory module and modulates its functionality to achieve a mechanistic coupling to a kinase domain in order to trigger downstream signaling events.
[Mh] Termos MeSH primário: Compostos de Amônio/metabolismo
Proteínas de Bactérias/metabolismo
Membrana Celular/metabolismo
Histidina Quinase/metabolismo
Transdução de Sinais
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Compostos de Amônio/química
Bactérias/genética
Bactérias/metabolismo
Proteínas de Bactérias/genética
Sítios de Ligação/genética
Cristalografia por Raios X
Histidina Quinase/química
Histidina Quinase/genética
Proteínas de Membrana Transportadoras/química
Proteínas de Membrana Transportadoras/genética
Proteínas de Membrana Transportadoras/metabolismo
Modelos Moleculares
Oxirredução
Ligação Proteica
Domínios Proteicos
Espalhamento a Baixo Ângulo
Homologia de Sequência de Aminoácidos
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Ammonium Compounds); 0 (Bacterial Proteins); 0 (Membrane Transport Proteins); EC 2.7.13.1 (Histidine Kinase)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180112
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02637-3


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[PMID]:28748404
[Au] Autor:Scariot FJ; Jahn L; Delamare APL; Echeverrigaray S
[Ad] Endereço:Institute of Biotechnology, University of Caxias do Sul, Caxias do Sul, Rio Grande Do Sul, Brazil.
[Ti] Título:Necrotic and apoptotic cell death induced by Captan on Saccharomyces cerevisiae.
[So] Source:World J Microbiol Biotechnol;33(8):159, 2017 Aug.
[Is] ISSN:1573-0972
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Captan is one of the most widely used broad-spectrum fungicide applied to control several early and late diseases of grapes, apples, and other fruits and vegetables, and as other phthalimide fungicides is defined as a multisite compound with thiol-reactivity. Captan can affect non-target organisms as yeasts, modifying microbial populations and fermentation processes. In this study, we asked whether Captan thiol-reactivity and other mechanisms are involved in acute Captan-induced cell death on aerobic growing Saccharomyces cerevisiae. Thus for, we analyze cellular protein and non-protein thiols, cell membrane integrity, reactive oxygen species accumulation, phosphatidylserine externalization, and apoptotic mutants behavior. The results showed that when submitted to acute Captan treatment most cells lost their membrane integrity and died by necrosis due to Captan reaction with thiols. However, part of the cells, even maintaining their membrane integrity, lost their culture ability. These cells showed an apoptotic behavior that may be the result of non-protein thiol depletion and consequent increase of reactive oxygen species (ROS). ROS accumulation triggers a metacaspase-dependent apoptotic cascade, as shown by the higher viability of the yca1-deleted mutant. Together, necrosis and apoptosis are responsible for the high mortality detected after acute Captan treatment of aerobically growing cells of S. cerevisiae.
[Mh] Termos MeSH primário: Apoptose/efeitos dos fármacos
Captana/farmacologia
Morte Celular/efeitos dos fármacos
Saccharomyces cerevisiae/efeitos dos fármacos
[Mh] Termos MeSH secundário: Membrana Celular/efeitos dos fármacos
Fermentação
Fungicidas Industriais/farmacologia
Viabilidade Microbiana/efeitos dos fármacos
Mutação
Necrose
Espécies Reativas de Oxigênio/metabolismo
Saccharomyces cerevisiae/genética
Saccharomyces cerevisiae/crescimento & desenvolvimento
Proteínas de Saccharomyces cerevisiae/genética
Proteínas de Saccharomyces cerevisiae/metabolismo
Compostos de Sulfidrila/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fungicides, Industrial); 0 (Reactive Oxygen Species); 0 (Saccharomyces cerevisiae Proteins); 0 (Sulfhydryl Compounds); EOL5G26Q9F (Captan)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170728
[St] Status:MEDLINE
[do] DOI:10.1007/s11274-017-2325-3



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