Base de dados : MEDLINE
Pesquisa : D12.776.097.120 [Categoria DeCS]
Referências encontradas : 19043 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 1905 ir para página                         

  1 / 19043 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28453834
[Au] Autor:Sánchez-Encinales V; Álvarez-Marín R; Pachón-Ibáñez ME; Fernández-Cuenca F; Pascual A; Garnacho-Montero J; Martínez-Martínez L; Vila J; Tomás MM; Cisneros JM; Bou G; Rodríguez-Baño J; Pachón J; Smani Y
[Ad] Endereço:Clinic Unit of Infectious Diseases, Microbiology and Preventive Medicine, Institute of Biomedicine of Seville, IBiS, University Hospital Virgen del Rocío/CSIC/University of Seville, Spain.
[Ti] Título:Overproduction of Outer Membrane Protein A by Acinetobacter baumannii as a Risk Factor for Nosocomial Pneumonia, Bacteremia, and Mortality Rate Increase.
[So] Source:J Infect Dis;215(6):966-974, 2017 03 15.
[Is] ISSN:1537-6613
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Background: Outer membrane protein A (OmpA) is a porin involved in Acinetobacter baumannii pathogenesis. However, OmpA clinical implication in hospital-acquired infections remains unknown. We aimed to determine whether OmpA overproduction was a risk factor associated with pneumonia, bacteremia, and mortality. Methods: We analyzed demographic, microbiological, and clinical data from 100 patients included in a unicenter cohort and 246 included in a unicenter cohort and a multicenter cohort. Representative isolates were classified into 2 groups: (1) isolates from patients colonized by A. baumannii (16 from the unicenter and 20 from the multicenter cohort) and (2) isolates from bacteremic or nonbacteremic patients with pneumonia (PP) caused by A. baumannii (13 from the unicenter and 23 from the multicenter cohort) Expression of ompA was determined with quantitative reverse-transcription polymerase chain reaction. Results: Isolates from PP overexpressed more ompA than those from colonized patients from the unicenter (ratio, 1.76 vs 0.36; P < .001) and the multicenter (1.36 vs 0.91; P = .03) cohorts. Among isolates from PP, those from bacteremic patients overexpressed nonsignificantly more ompA than those from nonbacteremic patients in the unicenter (ratio, 2.37 vs 1.43; P = .06) and the multicenter (2.03 vs 0.91; P = .14) cohorts. Multivariate analysis in both cohorts together showed ompA overexpression as independent risk factor for pneumonia (P < .001), bacteremia (P = .005), and death (P = .049). Conclusions: These data suggest that ompA overexpression is an associated factor for pneumonia, bacteremia, and death due to A. baumannii.
[Mh] Termos MeSH primário: Acinetobacter baumannii/genética
Bacteriemia/epidemiologia
Proteínas da Membrana Bacteriana Externa/genética
Infecção Hospitalar/epidemiologia
Pneumonia Bacteriana/epidemiologia
Sepse/mortalidade
[Mh] Termos MeSH secundário: Acinetobacter baumannii/isolamento & purificação
Adolescente
Adulto
Idoso
Idoso de 80 Anos ou mais
Animais
Infecção Hospitalar/microbiologia
Modelos Animais de Doenças
Feminino
Seres Humanos
Masculino
Camundongos
Camundongos Endogâmicos C57BL
Testes de Sensibilidade Microbiana
Meia-Idade
Análise Multivariada
Fatores de Risco
Índice de Gravidade de Doença
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE; MULTICENTER STUDY
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 149024-69-1 (OMPA outer membrane proteins)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1093/infdis/jix010


  2 / 19043 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29335469
[Au] Autor:Aunkham A; Zahn M; Kesireddy A; Pothula KR; Schulte A; Baslé A; Kleinekathöfer U; Suginta W; van den Berg B
[Ad] Endereço:Biochemistry-Electrochemistry Research Unit, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand.
[Ti] Título:Structural basis for chitin acquisition by marine Vibrio species.
[So] Source:Nat Commun;9(1):220, 2018 01 15.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Chitin, an insoluble polymer of N-acetylglucosamine, is one of the most abundant biopolymers on Earth. By degrading chitin, chitinolytic bacteria such as Vibrio harveyi are critical for chitin recycling and maintenance of carbon and nitrogen cycles in the world's oceans. A decisive step in chitin degradation is the uptake of chito-oligosaccharides by an outer membrane protein channel named chitoporin (ChiP). Here, we report X-ray crystal structures of ChiP from V. harveyi in the presence and absence of chito-oligosaccharides. Structures without bound sugar reveal a trimeric assembly with an unprecedented closing of the transport pore by the N-terminus of a neighboring subunit. Substrate binding ejects the pore plug to open the transport channel. Together with molecular dynamics simulations, electrophysiology and in vitro transport assays our data provide an explanation for the exceptional affinity of ChiP for chito-oligosaccharides and point to an important role of the N-terminal gate in substrate transport.
[Mh] Termos MeSH primário: Carbono/metabolismo
Quitina/metabolismo
Nitrogênio/metabolismo
Vibrio/metabolismo
[Mh] Termos MeSH secundário: Acetilglucosamina/metabolismo
Proteínas da Membrana Bacteriana Externa/química
Proteínas da Membrana Bacteriana Externa/genética
Proteínas da Membrana Bacteriana Externa/metabolismo
Ciclo do Carbono
Cristalografia por Raios X
Modelos Moleculares
Ciclo do Nitrogênio
Oceanos e Mares
Oligossacarídeos/metabolismo
Porinas/química
Porinas/genética
Porinas/metabolismo
Conformação Proteica
Água do Mar/química
Água do Mar/microbiologia
Vibrio/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Oligosaccharides); 0 (Porins); 1398-61-4 (Chitin); 7440-44-0 (Carbon); N762921K75 (Nitrogen); V956696549 (Acetylglucosamine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180306
[Lr] Data última revisão:
180306
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180117
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02523-y


  3 / 19043 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29197577
[Au] Autor:Liew CW; Hynson RM; Ganuelas LA; Shah-Mohammadi N; Duff AP; Kojima S; Homma M; Lee LK
[Ad] Endereço:School of Medical Sciences, The University of New South Wales, Australia.
[Ti] Título:Solution structure analysis of the periplasmic region of bacterial flagellar motor stators by small angle X-ray scattering.
[So] Source:Biochem Biophys Res Commun;495(2):1614-1619, 2018 01 08.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The bacterial flagellar motor drives the rotation of helical flagellar filaments to propel bacteria through viscous media. It consists of a dynamic population of mechanosensitive stators that are embedded in the inner membrane and activate in response to external load. This entails assembly around the rotor, anchoring to the peptidoglycan layer to counteract torque from the rotor and opening of a cation channel to facilitate an influx of cations, which is converted into mechanical rotation. Stator complexes are comprised of four copies of an integral membrane A subunit and two copies of a B subunit. Each B subunit includes a C-terminal OmpA-like peptidoglycan-binding (PGB) domain. This is thought to be linked to a single N-terminal transmembrane helix by a long unstructured peptide, which allows the PGB domain to bind to the peptidoglycan layer during stator anchoring. The high-resolution crystal structures of flagellar motor PGB domains from Salmonella enterica (MotB ) and Vibrio alginolyticus (PomB ) have previously been elucidated. Here, we use small-angle X-ray scattering (SAXS). We show that unlike MotB , the dimeric conformation of the PomB in solution differs to its crystal structure, and explore the functional relevance by characterising gain-of-function mutants as well as wild-type constructs of various lengths. These provide new insight into the conformational diversity of flagellar motor PGB domains and experimental verification of their overall topology.
[Mh] Termos MeSH primário: Proteínas da Membrana Bacteriana Externa/química
Proteínas de Bactérias/química
Flagelos/química
Proteínas Motores Moleculares/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas da Membrana Bacteriana Externa/genética
Proteínas de Bactérias/genética
Modelos Moleculares
Proteínas Motores Moleculares/genética
Domínios Proteicos
Estrutura Quaternária de Proteína
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Salmonella enterica/química
Salmonella enterica/genética
Espalhamento a Baixo Ângulo
Homologia de Sequência de Aminoácidos
Soluções
Vibrio alginolyticus/química
Vibrio alginolyticus/genética
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Bacterial Proteins); 0 (Molecular Motor Proteins); 0 (MotB protein, Bacteria); 0 (PomB protein, bacteria); 0 (Recombinant Proteins); 0 (Solutions)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171204
[St] Status:MEDLINE


  4 / 19043 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29254479
[Au] Autor:Sekizuka T; Nai E; Yoshida T; Endo S; Hamajima E; Akiyama S; Ikuta Y; Obana N; Kawaguchi T; Hayashi K; Noda M; Sumita T; Kokaji M; Katori T; Hashino M; Oba K; Kuroda M
[Ad] Endereço:Pathogen Genomics Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku, Tokyo, 162-8640, Japan.
[Ti] Título:Streptococcal toxic shock syndrome caused by the dissemination of an invasive emm3/ST15 strain of Streptococcus pyogenes.
[So] Source:BMC Infect Dis;17(1):774, 2017 12 18.
[Is] ISSN:1471-2334
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Streptococcus pyogenes (group A Streptococcus [GAS]) is a major human pathogen that causes a wide spectrum of clinical manifestations. Although invasive GAS (iGAS) infections are relatively uncommon, emm3/ST15 GAS is a highly virulent, invasive, and pathogenic strain. Global molecular epidemiology analysis has suggested that the frequency of emm3 GAS has been recently increasing. CASE PRESENTATION: A 14-year-old patient was diagnosed with streptococcal toxic shock syndrome and severe pneumonia, impaired renal function, and rhabdomyolysis. GAS was isolated from a culture of endotracheal aspirates and designated as KS030. Comparative genome analysis suggested that KS030 is classified as emm3 (emm-type) and ST15 (multilocus sequencing typing [MLST]), which is similar to iGAS isolates identified in the UK (2013) and Switzerland (2015). CONCLUSIONS: We conclude that the global dissemination of emm3/ST15 GAS strain has the potential to cause invasive disease.
[Mh] Termos MeSH primário: Choque Séptico/microbiologia
Infecções Estreptocócicas/microbiologia
Streptococcus pyogenes/isolamento & purificação
[Mh] Termos MeSH secundário: Antígenos de Bactérias/genética
Proteínas da Membrana Bacteriana Externa/genética
Seres Humanos
Epidemiologia Molecular
Tipagem de Sequências Multilocus
Choque Séptico/epidemiologia
Infecções Estreptocócicas/epidemiologia
Streptococcus pyogenes/classificação
Streptococcus pyogenes/genética
Suíça/epidemiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Antigens, Bacterial); 0 (Bacterial Outer Membrane Proteins)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180214
[Lr] Data última revisão:
180214
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171220
[St] Status:MEDLINE
[do] DOI:10.1186/s12879-017-2870-2


  5 / 19043 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28746830
[Au] Autor:Gilardi A; Bhamidimarri SP; Brönstrup M; Bilitewski U; Marreddy RKR; Pos KM; Benier L; Gribbon P; Winterhalter M; Windshügel B
[Ad] Endereço:Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Department Screening Port, Schnackenburgallee 114, 22525 Hamburg, Germany; Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany.
[Ti] Título:Biophysical characterization of E. coli TolC interaction with the known blocker hexaamminecobalt.
[So] Source:Biochim Biophys Acta;1861(11 Pt A):2702-2709, 2017 11.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The tripartite efflux pump AcrAB-TolC in E. coli is involved in drug resistance by transporting antibiotics out of the cell. The outer membrane protein TolC can be blocked by various cations, including hexaamminecobalt, thereby TolC represents a potential target for reducing antimicrobial resistance as its blockage may improve efficacy of antibiotics. METHODS: We utilized single channel electrophysiology measurements for studying TolC conductance in the absence and presence of the known TolC blocker hexaamminecobalt. Association and dissociation constants of hexaamminecobalt were determined using surface plasmon resonance measurements. Minimum inhibitory concentration (MIC) assays in the absence and presence of antibiotics were carried out for investigating the antibacterial effect of hexaamminecobalt and its potential to reduce MICs. RESULTS: TolC gating in the absence of any ligand is voltage dependent and asymmetric at high applied voltages. Hexaamminecobalt binds to TolC with high affinity and kinetic data revealed fast association and dissociation rates. Despite potent binding to TolC, hexaamminecobalt does not possess an intrinsic antimicrobial activity against E. coli nor does it reduce MIC values of antibiotics erythromycin and fusidic acid. CONCLUSIONS: TolC opening can be effectively blocked by small molecules. More potent channel blockers are needed in order to investigate the eligibility of TolC as drug target. GENERAL SIGNIFICANCE: TolC, a potentially interesting pharmaceutical target can be addressed by small molecules, blocking the channel. Biophysical characterization of the binding processes will support future identification and optimisation of more potent TolC blockers in order to validate TolC as a pharmaceutical target.
[Mh] Termos MeSH primário: Proteínas da Membrana Bacteriana Externa/química
Farmacorresistência Bacteriana Múltipla/genética
Proteínas de Escherichia coli/química
Escherichia coli/efeitos dos fármacos
Proteínas de Membrana Transportadoras/química
[Mh] Termos MeSH secundário: Proteínas da Membrana Bacteriana Externa/antagonistas & inibidores
Proteínas da Membrana Bacteriana Externa/efeitos dos fármacos
Proteínas da Membrana Bacteriana Externa/genética
Fenômenos Biofísicos
Cobalto/farmacologia
Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos
Escherichia coli/genética
Proteínas de Escherichia coli/antagonistas & inibidores
Proteínas de Escherichia coli/genética
Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos
Proteínas de Membrana Transportadoras/genética
Ressonância de Plasmônio de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Escherichia coli Proteins); 0 (Membrane Transport Proteins); 0 (tolC protein, E coli); 15365-75-0 (hexaamminecobalt(II)); 3G0H8C9362 (Cobalt)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180208
[Lr] Data última revisão:
180208
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE


  6 / 19043 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29298355
[Au] Autor:Liu Y; Zhou X; Liu W; Xiong X; Lv C; Zhou X; Miao W
[Ad] Endereço:Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China.
[Ti] Título:Functional regions of HpaXm as elicitors with specific heat tolerance induce the hypersensitive response or plant growth promotion in nonhost plants.
[So] Source:PLoS One;13(1):e0188788, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:HpaXm produced by the cotton leaf blight bacterium Xanthomonas citri subsp. malvacearum is a novel harpin elicitor of the induced hypersensitive response (HR) in tobacco. We investigated whether fragments of HpaXm, compared with fragments of Hpa1Xoo, are sufficient for HR or plant growth promotion (PGP) elicitation using four synthetic peptides (HpaXm35-51, HpaXm10-39, Hpa1Xoo36-52 and Hpa1Xoo10-40). We also heated the fragments to determine the heat tolerance of the functional fragments. HpaXm35-51 and Hpa1Xoo36-52 induced hypersensitive response (HR). Bursts of reactive oxygen intermediates (ROI) induced by HpaXm35-51 and Hpa1Xoo36-52 were earlier and stronger than those induced by HpaXm and Hpa1Xoo. In plants treated with HpaXm35-51 or Hpa1Xoo36-52, the expression of the HR marker genes Hin1 and Hsr203J and the active oxygen metabolism related gene AOX were significantly upregulated. These findings suggest that the predicted α-helical structures of the HpaXm35-51 and Hpa1Xoo36-52 fragments are crucial for HR. PGP result by soaking seeds in unheated/heated HpaXm10-39 or Hpa1Xoo10-40 solution prior to transfer, which obviously enhances root growth and the aerial parts of plants. The PGP related gene NtEXP6 was greatly enhanced when plants were sprayed with a solution of HpaXm10-39 or Hpa1Xoo10-40; heated fragment treatments induced higher levels of NtEXP6 expression than unheated HpaXm fragments. In addition, HR marker genes induced by the heated fragments had lower expression levels than when induced with unheated HpaXm fragments. Moreover, the expression levels of HR marker genes and PGP related genes induced by treatment with Hpa1Xoo fragments before or after heating were the opposite of those induced by HpaXm fragments. Different functional fragments of harpin and different harpins with the same functional region have different degrees of heat tolerance. Therefore, the heat resistance of harpin is conservative, but the degree of heat tolerance of the functional fragments is specific.
[Mh] Termos MeSH primário: Adaptação Fisiológica
Temperatura Alta
Desenvolvimento Vegetal
Xanthomonas/fisiologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas da Membrana Bacteriana Externa/química
Proteínas da Membrana Bacteriana Externa/genética
Espécies Reativas de Oxigênio
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Reactive Oxygen Species)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180206
[Lr] Data última revisão:
180206
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180104
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0188788


  7 / 19043 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28467715
[Au] Autor:Boags A; Hsu PC; Samsudin F; Bond PJ; Khalid S
[Ad] Endereço:School of Chemistry, University of Southampton , Southampton, United Kingdom , SO17 1BJ.
[Ti] Título:Progress in Molecular Dynamics Simulations of Gram-Negative Bacterial Cell Envelopes.
[So] Source:J Phys Chem Lett;8(11):2513-2518, 2017 Jun 01.
[Is] ISSN:1948-7185
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacteria are protected by complex molecular architectures known as the cell envelope. The cell envelope is composed of regions with distinct chemical compositions and physical properties, namely, membranes and a cell wall. To develop novel antibiotics to combat pathogenic bacteria, molecular level knowledge of the structure, dynamics, and interplay between the chemical components of the cell envelope that surrounds bacterial cells is imperative. In addition, conserved molecular patterns associated with the bacterial envelope are recognized by receptors as part of the mammalian defensive response to infection, and an improved understanding of bacteria-host interactions would facilitate the search for novel immunotherapeutics. This Perspective introduces an emerging area of computational biology: multiscale molecular dynamics simulations of chemically complex models of bacterial lipids and membranes. We discuss progress to date, and identify areas for future development that will enable the study of aspects of the membrane components that are as yet unexplored by computational methods.
[Mh] Termos MeSH primário: Antibacterianos
Proteínas da Membrana Bacteriana Externa/química
Membrana Celular/química
Bactérias Gram-Negativas
Simulação de Dinâmica Molecular
[Mh] Termos MeSH secundário: Parede Celular
Infecções por Bactérias Gram-Negativas/tratamento farmacológico
Modelos Moleculares
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Outer Membrane Proteins)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180205
[Lr] Data última revisão:
180205
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jpclett.7b00473


  8 / 19043 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28745311
[Au] Autor:Chen F; Cui G; Wang S; Nair MKM; He L; Qi X; Han X; Zhang H; Zhang JR; Su J
[Ad] Endereço:Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
[Ti] Título:Outer membrane vesicle-associated lipase FtlA enhances cellular invasion and virulence in Francisella tularensis LVS.
[So] Source:Emerg Microbes Infect;6(7):e66, 2017 Jul 26.
[Is] ISSN:2222-1751
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Francisella tularensis is a highly infectious intracellular pathogen that infects a wide range of host species and causes fatal pneumonic tularemia in humans. ftlA was identified as a potential virulence determinant of the F. tularensis live vaccine strain (LVS) in our previous transposon screen, but its function remained undefined. Here, we show that an unmarked deletion mutant of ftlA was avirulent in a pneumonia mouse model with a severely impaired capacity to infect host cells. Consistent with its sequence homology with GDSL lipase/esterase family proteins, the FtlA protein displayed lipolytic activity in both E. coli and F. tularensis with a preference for relatively short carbon-chain substrates. FtlA thus represents the first F. tularensis lipase to promote bacterial infection of host cells and in vivo fitness. As a cytoplasmic protein, we found that FtlA was secreted into the extracellular environment as a component of outer membrane vesicles (OMVs). Further confocal microscopy analysis revealed that the FtlA-containing OMVs isolated from F. tularensis LVS attached to the host cell membrane. Finally, the OMV-associated FtlA protein complemented the genetic deficiency of the ΔftlA mutant in terms of host cell infection when OMVs purified from the parent strain were co-incubated with the mutant bacteria. These lines of evidence strongly suggest that the FtlA lipase promotes F. tularensis adhesion and internalization by modifying bacterial and/or host molecule(s) when it is secreted as a component of OMVs.
[Mh] Termos MeSH primário: Proteínas da Membrana Bacteriana Externa/metabolismo
Francisella tularensis/enzimologia
Francisella tularensis/patogenicidade
Lipase/metabolismo
Macrófagos/microbiologia
[Mh] Termos MeSH secundário: Células A549
Animais
Aderência Bacteriana
Carga Bacteriana
Proteínas da Membrana Bacteriana Externa/química
Proteínas da Membrana Bacteriana Externa/isolamento & purificação
Linhagem Celular
Modelos Animais de Doenças
Células Epiteliais/microbiologia
Escherichia coli/metabolismo
Francisella tularensis/genética
Francisella tularensis/fisiologia
Deleção de Genes
Seres Humanos
Fígado/microbiologia
Pulmão/citologia
Camundongos
Mutação
Células RAW 264.7
Baço/microbiologia
Tularemia/microbiologia
Virulência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); EC 3.1.1.3 (Lipase)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180118
[Lr] Data última revisão:
180118
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.1038/emi.2017.53


  9 / 19043 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29284249
[Au] Autor:Schreterova E; Bhide M; Potocnakova L; Borszekova Pulzova L
[Ad] Endereço:Laboratory of Biomedical Microbiology and Immunology, Department of Microbiology and Immunology, University of Veterinary Medicine and Pharmacy, 041 81 Kosice, Slovakia. eva.kendrovska@gmail.com.
[Ti] Título:Design, construction and evaluation of multi-epitope antigens for diagnosis of Lyme disease.
[So] Source:Ann Agric Environ Med;24(4):696-701, 2017 Dec 23.
[Is] ISSN:1898-2263
[Cp] País de publicação:Poland
[La] Idioma:eng
[Ab] Resumo:INTRODUCTION: Introduction and objective. Lyme disease (LD) is the most common vector-borne disease in the temperate zone of the Northern Hemisphere. Diagnosis of LD is mainly based on clinical symptoms supported with serology (detection of anti-Borrelia antibodies) and is often misdiagnosed in areas of endemicity. MATERIAL AND METHODS: In this study, the chimeric proteins (A/C-2, A/C-4 and A/C-7.1) consisting of B-cell epitopes of outer surface proteins OspA and OspC from Borrelia genospecies prevalent in Eastern Slovakia, were designed, over-expressed in E. coli, and used to detect specific anti-Borrelia antibodies in serologically characterized sera from patients with Lyme-like symptoms to evaluate their diagnostic potential. RESULTS: Results showed that chimeras vary in their immuno-reactivity when tested with human sera. Compared with the results obtained from a two-tier test, the application of recombinant multi-epitope chimeric proteins as diagnosis antigens, produced fair agreement in the case of A/C-2 (0.20<κ<0.40) and good agreement (0.60<κ<0.80) when A/C-7.1 was used as capture antigen. Chimera A/C-4 were excluded from further study due to loss of reactivity with OspA-specific antibodies. CONCLUSIONS: The combination of specific B-cell epitopes from OspA and OspC proteins may improve the diagnostic accuracy of serologic assays, but further studies are required to address this hypothesis.
[Mh] Termos MeSH primário: Borrelia burgdorferi/isolamento & purificação
Ensaio de Imunoadsorção Enzimática/métodos
Epitopos de Linfócito B/análise
Doença de Lyme/diagnóstico
[Mh] Termos MeSH secundário: Anticorpos Antibacterianos/análise
Anticorpos Antibacterianos/imunologia
Antígenos de Superfície/análise
Antígenos de Superfície/genética
Antígenos de Superfície/imunologia
Proteínas da Membrana Bacteriana Externa/análise
Proteínas da Membrana Bacteriana Externa/genética
Proteínas da Membrana Bacteriana Externa/imunologia
Vacinas Bacterianas/análise
Vacinas Bacterianas/genética
Vacinas Bacterianas/imunologia
Borrelia burgdorferi/genética
Borrelia burgdorferi/imunologia
Epitopos de Linfócito B/imunologia
Seres Humanos
Lipoproteínas/análise
Lipoproteínas/genética
Lipoproteínas/imunologia
Doença de Lyme/imunologia
Doença de Lyme/microbiologia
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Bacterial); 0 (Antigens, Surface); 0 (Bacterial Outer Membrane Proteins); 0 (Bacterial Vaccines); 0 (Epitopes, B-Lymphocyte); 0 (Lipoproteins); 0 (OspA protein)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180105
[Lr] Data última revisão:
180105
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171230
[St] Status:MEDLINE


  10 / 19043 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29223157
[Au] Autor:Sidorin EV; Khomenko VA; Kim NY; Dmitrenok PS; Stenkova AM; Novikova OD; Solov'eva TF
[Ad] Endereço:Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Vladivostok, 690022, Russia. sev1972@mail.ru.
[Ti] Título:Self-Organization of Recombinant Membrane Porin OmpF from Yersinia pseudotuberculosis in Aqueous Environments.
[So] Source:Biochemistry (Mosc);82(11):1304-1313, 2017 Nov.
[Is] ISSN:1608-3040
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Recombinant porin OmpF (an integral protein of bacterial outer membrane) from Yersinia pseudotuberculosis was synthesized in Escherichia coli cells as inclusion bodies. By combining the methods of anion-exchange and gel filtration chromatographies, recombinant OmpF (rOmpF) was isolated as an individual protein in its denatured state, and its characteristic properties (molecular mass, N-terminal amino acid sequence, and hydrodynamic radius of the protein in 8 M urea solution) were determined. According to the data of gel filtration, dynamic light scattering, optical spectroscopy, and binding of the hydrophobic fluorescent probe 8-anilino-1-naphthalenesulfonic acid, the rOmpF is fully unfolded in 8 M urea and exists in random coil conformation. In aqueous solutions, rOmpF undergoes conformational changes, reversible self-association, and aggregation. When transferred from 8 M urea into water, PBS (containing 0.15 M NaCl, pH 7.4), or buffer containing 0.8 M urea (pH 8.0), fully unfolded rOmpF forms relatively compact monomeric intermediates prone to self-association with formation of multimers. The oligomeric intermediates have high content of native protein-like secondary structure and pronounced tertiary structure. In acidic media (pH 5.0, close to the protein isoelectric point), rOmpF undergoes rapid irreversible aggregation. Therefore, we found that medium composition significantly affects both porin folding and processes of its self-association and aggregation.
[Mh] Termos MeSH primário: Porinas/química
Yersinia pseudotuberculosis/química
[Mh] Termos MeSH secundário: Proteínas da Membrana Bacteriana Externa
Proteínas de Bactérias
Escherichia coli/genética
Escherichia coli/metabolismo
Corpos de Inclusão
Porinas/biossíntese
Porinas/isolamento & purificação
Conformação Proteica
Desnaturação Proteica/efeitos dos fármacos
Dobramento de Proteína/efeitos dos fármacos
Multimerização Proteica/efeitos dos fármacos
Renaturação Proteica/efeitos dos fármacos
Proteínas Recombinantes
Soluções/química
Soluções/farmacologia
Água
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Bacterial Proteins); 0 (OmpF protein); 0 (Porins); 0 (Recombinant Proteins); 0 (Solutions); 059QF0KO0R (Water)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180103
[Lr] Data última revisão:
180103
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171211
[St] Status:MEDLINE
[do] DOI:10.1134/S0006297917110086



página 1 de 1905 ir para página                         
   


Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde