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Pesquisa : B03.353.750.737.872.260 [Categoria DeCS]
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[PMID]:28963931
[Au] Autor:Kim AR; Ahn KB; Kim HY; Seo HS; Kum KY; Yun CH; Han SH
[Ad] Endereço:Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 08826, Republic of Korea.
[Ti] Título:Streptococcus gordonii lipoproteins induce IL-8 in human periodontal ligament cells.
[So] Source:Mol Immunol;91:218-224, 2017 11.
[Is] ISSN:1872-9142
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Streptococcus gordonii, a Gram-positive oral bacterium, is a life-threatening pathogen that causes infective endocarditis. It is frequently isolated from the periapical lesions of patients with apical periodontitis and has thus been implicated in inflammatory responses. However, little is known about the virulence factors of S. gordonii responsible for the induction of inflammatory responses in the periapical areas. Here, we investigated the role of S. gordonii cell wall-associated virulence factors on interleukin (IL)-8 induction in human periodontal ligament (PDL) cells using ethanol-inactivated wild-type S. gordonii, a lipoteichoic acid (LTA)-deficient mutant (ΔltaS), and a lipoprotein-deficient mutant (Δlgt). Wild-type S. gordonii induced IL-8 expression at both the protein and mRNA levels in human PDL cells in a dose- and time-dependent manner. A transient transfection and reporter gene assay demonstrated that wild-type S. gordonii activated Toll-like receptor 2 (TLR2). Additionally, IL-8 production induced by wild-type S. gordonii was substantially inhibited by anti-TLR2-neutralizing antibodies. Both wild-type S. gordonii and the ΔltaS mutant induced IL-8 production; however, this response was not observed when cells were stimulated with the Δlgt mutant. Interestingly, lipoproteins purified from S. gordonii induced IL-8 production, whereas purified LTA did not. In addition, purified lipoproteins stimulated TLR2 more potently than LTA. Furthermore, S. gordonii-induced IL-8 expression was specifically inhibited by blocking p38 kinase, while lipoprotein-induced IL-8 expression was inhibited by blocking p38 kinase, ERK, or JNK. Of particular note, exogenous addition of purified S. gordonii lipoproteins enhanced Δlgt-induced IL-8 production in human PDL cells to an extent similar to that induced by the wild-type strain. Collectively, these results suggest that lipoproteins are an important component of S. gordonii for the induction of IL-8 production in human PDL cells through TLR2 activation. Therefore, lipoproteins potentially contribute to inflammatory apical periodontitis.
[Mh] Termos MeSH primário: Proteínas de Bactérias/imunologia
Interleucina-8/imunologia
Lipoproteínas/imunologia
Ligamento Periodontal/imunologia
Periodontite/imunologia
Streptococcus gordonii/imunologia
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Regulação da Expressão Gênica/imunologia
Células HEK293
Seres Humanos
Lipoproteínas/genética
Mutação
Ligamento Periodontal/patologia
Periodontite/genética
Periodontite/microbiologia
Periodontite/patologia
Streptococcus gordonii/genética
Receptor 2 Toll-Like/imunologia
Proteínas Quinases p38 Ativadas por Mitógeno/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (IL8 protein, human); 0 (Interleukin-8); 0 (Lipoproteins); 0 (TLR2 protein, human); 0 (Toll-Like Receptor 2); EC 2.7.11.24 (p38 Mitogen-Activated Protein Kinases)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171120
[Lr] Data última revisão:
171120
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171001
[St] Status:MEDLINE


  2 / 283 MEDLINE  
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[PMID]:28790818
[Au] Autor:Kalia P; Jain A; Radha Krishnan R; Demuth DR; Steinbach-Rankins JM
[Ad] Endereço:Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry.
[Ti] Título:Peptide-modified nanoparticles inhibit formation of biofilms with .
[So] Source:Int J Nanomedicine;12:4553-4562, 2017.
[Is] ISSN:1178-2013
[Cp] País de publicação:New Zealand
[La] Idioma:eng
[Ab] Resumo:PURPOSE: The interaction of g with commensal streptococci promotes colonization of the oral cavity. We previously showed that a synthetic peptide (BAR) derived from potently inhibited the formation of biofilms (IC =1.3 µM) and reduced virulence in a mouse model of periodontitis. Thus, BAR represents a novel therapeutic to control periodontitis by limiting colonization of the oral cavity. Here, we sought to develop drug-delivery vehicles for potential use in the oral cavity that comprise BAR-modified poly(lactic-co-glycolic)acid (PLGA) nanoparticles (NPs). METHODS: PLGA-NPs were initially modified with palmitylated avidin and subsequently conjugated with biotinylated BAR. The extent of BAR modification was quantified using a fluorescent-labeled peptide. Inhibition of adherence to by BAR-modified NPs was compared with free peptide using a two-species biofilm model. RESULTS: BAR-modified NPs exhibited an average size of 99±29 nm and a more positive surface charge than unmodified NPs (zeta potentials of -7 mV and -25 mV, respectively). Binding saturation occurred when 37 nmol BAR/mg of avidin-NPs was used, which resulted in a payload of 7.42 nmol BAR/mg NPs. BAR-modified NPs bound to in a dose-dependent manner and more potently inhibited adherence and biofilm formation relative to an equimolar amount of free peptide (IC of 0.2 µM versus 1.3 µM). BAR-modified NPs also disrupted the preformed biofilms more effectively than free peptide. Finally, we demonstrate that BAR-modified NPs promoted multivalent association with , providing an explanation for the increased effectiveness of NPs. CONCLUSION: These results indicate that BAR-modified NPs deliver a higher local dose of peptide and may represent a more effective therapeutic approach to limit colonization of the oral cavity compared to treatment with formulations of free peptide.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Nanopartículas/química
Peptídeos/farmacologia
Porphyromonas gingivalis/efeitos dos fármacos
Streptococcus gordonii/química
[Mh] Termos MeSH secundário: Antibacterianos/administração & dosagem
Antibacterianos/química
Aderência Bacteriana/efeitos dos fármacos
Proteínas de Bactérias/química
Biofilmes/efeitos dos fármacos
Sistemas de Liberação de Medicamentos/métodos
Ácido Láctico/química
Nanopartículas/administração & dosagem
Peptídeos/química
Ácido Poliglicólico/química
Porphyromonas gingivalis/fisiologia
Streptococcus gordonii/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Proteins); 0 (Peptides); 0 (polylactic acid-polyglycolic acid copolymer); 26009-03-0 (Polyglycolic Acid); 33X04XA5AT (Lactic Acid)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171030
[Lr] Data última revisão:
171030
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170810
[St] Status:MEDLINE
[do] DOI:10.2147/IJN.S139178


  3 / 283 MEDLINE  
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[PMID]:28736072
[Au] Autor:Sweidan A; Chollet-Krugler M; Sauvager A; van de Weghe P; Chokr A; Bonnaure-Mallet M; Tomasi S; Bousarghin L
[Ad] Endereço:U-1241 INSERM-INRA, Equipe CIMIAD, Univ. Rennes 1, Univ. Bretagne Loire, 2 Avenue du Pr. Léon Bernard, F-35043 Rennes, France; Laboratory of Microbiology, Department of Life and Earth Sciences, Faculty of Sciences I, Lebanese University, Hadath Campus, Beirut, Lebanon.
[Ti] Título:Antibacterial activities of natural lichen compounds against Streptococcus gordonii and Porphyromonas gingivalis.
[So] Source:Fitoterapia;121:164-169, 2017 Sep.
[Is] ISSN:1873-6971
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The oral bacteria not only infect the mouth and reside there, but also travel through the blood and reach distant body organs. If left untreated, the dental biofilm that can cause destructive inflammation in the oral cavity may result in serious medical complications. In dental biofilm, Streptococcus gordonii, a primary oral colonizer, constitutes the platform on which late pathogenic colonizers like Porphyromonas gingivalis, the causative agent of periodontal diseases, will bind. The aim of this study was to determine the antibacterial activity of eleven natural lichen compounds belonging to different chemical families and spanning from linear into cyclic and aromatic structures to uncover new antibiotics which can fight against the oral bacteria. The compounds were screened by broth microdilution assay. Three compounds were shown to have promising antibacterial activities where the depsidone core with certain functional groups constituted the best compound, psoromic acid, with the lowest MICs=11.72 and 5.86µg/mL against S. gordonii and P. gingivalis, respectively. The compounds screened had promising antibacterial activity which might be attributed to some important functional groups as discussed in our study. The best compounds did not induce the death of gingival epithelial carcinoma cells (Ca9-22). These results introduce new compounds having potent antibacterial activities against oral pathogens causing serious medical complications.
[Mh] Termos MeSH primário: Antibacterianos/química
Líquens/química
Porphyromonas gingivalis/efeitos dos fármacos
Streptococcus gordonii/efeitos dos fármacos
[Mh] Termos MeSH secundário: Antibacterianos/isolamento & purificação
Biofilmes/efeitos dos fármacos
Linhagem Celular Tumoral
Seres Humanos
Testes de Sensibilidade Microbiana
Estrutura Molecular
Boca/microbiologia
Doenças Periodontais/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170725
[St] Status:MEDLINE


  4 / 283 MEDLINE  
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[PMID]:28571487
[Au] Autor:Garcia SS; Blackledge MS; Michalek S; Su L; Ptacek T; Eipers P; Morrow C; Lefkowitz EJ; Melander C; Wu H
[Ad] Endereço:1 Department of Pediatric Dentistry, University of Alabama at Birmingham, Birmingham, AL, USA.
[Ti] Título:Targeting of Streptococcus mutans Biofilms by a Novel Small Molecule Prevents Dental Caries and Preserves the Oral Microbiome.
[So] Source:J Dent Res;96(7):807-814, 2017 Jul.
[Is] ISSN:1544-0591
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Dental caries is a costly and prevalent disease characterized by the demineralization of the tooth's enamel. Disease outcome is influenced by host factors, dietary intake, cariogenic bacteria, and other microbes. The cariogenic bacterial species Streptococcus mutans metabolizes sucrose to initiate biofilm formation on the tooth surface and consequently produces lactic acid to degrade the tooth's enamel. Persistence of S. mutans biofilms in the oral cavity can lead to tooth decay. To date, no anticaries therapies that specifically target S. mutans biofilms but do not disturb the overall oral microbiome are available. We screened a library of 2-aminoimidazole antibiofilm compounds with a biofilm dispersion assay and identified a small molecule that specifically targets S. mutans biofilms. At 5 µM, the small molecule annotated 3F1 dispersed 50% of the established S. mutans biofilm but did not disperse biofilms formed by the commensal species Streptococcus sanguinis or Streptococcus gordonii. 3F1 dispersed S. mutans biofilms independently of biofilm-related factors such as antigen I/II and glucosyltransferases. 3F1 treatment effectively prevented dental caries by controlling S. mutans in a rat caries model without perturbing the oral microbiota. Our study demonstrates that selective targeting of S. mutans biofilms by 3F1 was able to effectively reduce dental caries in vivo without affecting the overall oral microbiota shaped by the intake of dietary sugars, suggesting that the pathogenic biofilm-specific treatment is a viable strategy for disease prevention.
[Mh] Termos MeSH primário: Biofilmes/efeitos dos fármacos
Cárie Dentária/prevenção & controle
Imidazóis/farmacologia
Microbiota/efeitos dos fármacos
Streptococcus mutans/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Esmalte Dentário/efeitos dos fármacos
Microscopia Confocal
Reação em Cadeia da Polimerase
Ratos
Streptococcus gordonii/efeitos dos fármacos
Streptococcus sanguis/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Imidazoles); 7720-39-0 (2-aminoimidazole)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170828
[Lr] Data última revisão:
170828
[Sb] Subgrupo de revista:D; IM
[Da] Data de entrada para processamento:170603
[St] Status:MEDLINE
[do] DOI:10.1177/0022034517698096


  5 / 283 MEDLINE  
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[PMID]:28414782
[Au] Autor:Arrigucci R; Pozzi G
[Ad] Endereço:Public Health Research Institute, Rutgers, The State University of New Jersey, Newark, NJ, United States of America.
[Ti] Título:Identification of the chain-dispersing peptidoglycan hydrolase LytB of Streptococcus gordonii.
[So] Source:PLoS One;12(4):e0176117, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacterial cell division ends with the separation of the daughter cells, a process that requires peptidoglycan hydrolases (PGHs). Bacteria lacking cell separating PGHs are impaired in cell separation with the formation of long chains or clusters. We identified a gene in Streptococcus gordonii encoding for a putative glucosaminidase (lytB). The lytB isogenic mutant grew in long bacterial chains and resulted in impaired biofilm formation. Purified recombinant LytB showed a murolytic activity on Micrococcus lysodeikticus cell suspension and was able to disperse the long chains of the mutant, restoring the wild type diplococci/short chain phenotype. LytB protein was localized only in culture supernatant cell fraction of S. gordonii, and co-cultures of wild type and lytB mutant showed a significant reduction of bacterial chain length, indicating that LytB is a secreted enzyme. Our results demonstrate that LytB is a secreted peptidoglycan hydrolase required for S. gordonii cell separation.
[Mh] Termos MeSH primário: Proteínas de Bactérias/genética
N-Acetil-Muramil-L-Alanina Amidase/genética
Peptidoglicano/genética
Streptococcus gordonii/genética
[Mh] Termos MeSH secundário: Biofilmes
Divisão Celular/genética
Técnicas de Cocultura/métodos
Micrococcus/genética
Mutação/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Peptidoglycan); EC 3.5.1.- (LytB protein, Streptococcus); EC 3.5.1.28 (N-Acetylmuramoyl-L-alanine Amidase)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170505
[Lr] Data última revisão:
170505
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170418
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0176117


  6 / 283 MEDLINE  
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[PMID]:28253369
[Au] Autor:Martin B; Tamanai-Shacoori Z; Bronsard J; Ginguené F; Meuric V; Mahé F; Bonnaure-Mallet M
[Ad] Endereço:EA 1254 Microbiologie Risques infectieux, Université de Rennes 1, Université Européenne de Bretagne, Rennes, France.
[Ti] Título:A new mathematical model of bacterial interactions in two-species oral biofilms.
[So] Source:PLoS One;12(3):e0173153, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Periodontitis are bacterial inflammatory diseases, where the bacterial biofilms present on the tooth-supporting tissues switch from a healthy state towards a pathogenic state. Among bacterial species involved in the disease, Porphyromonas gingivalis has been shown to induce dysbiosis, and to induce virulence of otherwise healthy bacteria like Streptococcus gordonii. During biofilm development, primary colonizers such as S. gordonii first attach to the surface and allow the subsequent adhesion of periodontal pathogens such as P. gingivalis. Interactions between those two bacteria have been extensively studied during the adhesion step of the biofilm. The aim of the study was to understand interactions of both species during the growing phase of the biofilm, for which little knowledge is available, using a mathematical model. This two-species biofilm model was based on a substrate-dependent growth, implemented with damage parameters, and validated thanks to data obtained on experimental biofilms. Three different hypothesis of interactions were proposed and assayed using this model: independence, competition between both bacteria species, or induction of toxicity by one species for the other species. Adequacy between experimental and simulated biofilms were found with the last hypothetic mathematical model. This new mathematical model of two species bacteria biofilms, dependent on different substrates for growing, can be applied to any bacteria species, environmental conditions, or steps of biofilm development. It will be of great interest for exploring bacterial interactions in biofilm conditions.
[Mh] Termos MeSH primário: Biofilmes
Modelos Biológicos
Boca/microbiologia
Porphyromonas gingivalis/fisiologia
Streptococcus gordonii/fisiologia
[Mh] Termos MeSH secundário: Seres Humanos
Microscopia Eletrônica de Varredura
Porphyromonas gingivalis/crescimento & desenvolvimento
Porphyromonas gingivalis/patogenicidade
Streptococcus gordonii/crescimento & desenvolvimento
Streptococcus gordonii/patogenicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170907
[Lr] Data última revisão:
170907
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170303
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0173153


  7 / 283 MEDLINE  
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[PMID]:28167145
[Au] Autor:Martín-Galiano AJ
[Ad] Endereço:Instituto de Salud Carlos III, Centro Nacional de Microbiología, Carretera a Pozuelo, km 2.2, Majadahonda, 28220 Madrid, Spain. Electronic address: mgaliano@isciii.es.
[Ti] Título:The MiiA motif is a common marker present in polytopic surface proteins of oral and urinary tract invasive bacteria.
[So] Source:Infect Genet Evol;49:283-292, 2017 Apr.
[Is] ISSN:1567-7257
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Many surface virulence factors of bacterial pathogens show mosaicism and confounding phylogenetic origin. The Streptococcus gordonii platelet-binding GspB protein, the Streptococcus sanguinis SrpA adhesin and the Streptococcus pneumoniae DiiA protein, share an imperfect 27-residue motif. Given the disparate domain architectures of these proteins and its association to invasive disease, this motif was named MiiA from Multiarchitecture invasion-involved motif A. MiiA is predicted to adopt a beta-sheet folding, probably related to the Ig-like fold, with a symmetrical positioning of two conserved aspartic residues. A specific hidden Markov model profiling MiiA was built, which specifically detected the motif in proteins from 58 species, mainly in cell-wall proteins from Gram-positive bacteria. These proteins contained one to ten MiiA motifs, which were embedded within larger repeat units of 70-82 residues. MiiA motifs combined to other domains and elements such as coiled-coils and low-complexity regions. The species carrying MiiA-proteins included commensals from the urogenital tract and the oral cavity, which can cause opportunistic endocarditis and sepsis. Intra-protein MiiA repeats showed a complex mixture of orthologal, paralogal and inter-species relationships, suggestive of a multistep origin. Presence of these repeats in proteins involved in oligosaccharide recognition and lifestyle of species suggest a putative function for MiiA repeats in sugars binding, probably those present in receptors of epithelial and blood cells. MiiA modules appear to have been transferred horizontally between species co-habiting in the same niche to create their own MiiA-containing determinants. The present work provides a global study and a catalog of potential MiiA virulence factors that should be analyzed experimentally.
[Mh] Termos MeSH primário: Proteínas de Bactérias/genética
Sequência Conservada
Filogenia
Streptococcus gordonii/genética
Streptococcus pneumoniae/genética
Streptococcus sanguis/genética
[Mh] Termos MeSH secundário: Motivos de Aminoácidos
Proteínas de Bactérias/química
Expressão Gênica
Seres Humanos
Cadeias de Markov
Doenças da Boca/microbiologia
Streptococcus gordonii/classificação
Streptococcus gordonii/isolamento & purificação
Streptococcus pneumoniae/classificação
Streptococcus pneumoniae/isolamento & purificação
Streptococcus sanguis/classificação
Streptococcus sanguis/isolamento & purificação
Infecções Urinárias/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (serine-rich glycoprotein A, Streptococcus sanguis)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170208
[St] Status:MEDLINE


  8 / 283 MEDLINE  
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[PMID]:28038357
[Au] Autor:Kim HY; Baik JE; Ahn KB; Seo HS; Yun CH; Han SH
[Ad] Endereço:Department of Oral Microbiology and Immunology, DRI and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 08826, Republic of Korea.
[Ti] Título:Streptococcus gordonii induces nitric oxide production through its lipoproteins stimulating Toll-like receptor 2 in murine macrophages.
[So] Source:Mol Immunol;82:75-83, 2017 Feb.
[Is] ISSN:1872-9142
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Streptococcus gordonii, a Gram-positive commensal in the oral cavity, is an opportunistic pathogen that can cause endodontic and systemic infections resulting in infective endocarditis. Lipoteichoic acid (LTA) and lipoprotein are major virulence factors of Gram-positive bacteria that are preferentially recognized by Toll-like receptor 2 (TLR2) on immune cells. In the present study, we investigated the effect of S. gordonii LTA and lipoprotein on the production of the representative inflammatory mediator nitric oxide (NO) by the mouse macrophages. Heat-killed S. gordonii wild-type and an LTA-deficient mutant (ΔltaS) but not a lipoprotein-deficient mutant (Δlgt) induced NO production in mouse primary macrophages and the cell line, RAW 264.7. S. gordonii wild-type and ΔltaS also induced the expression of inducible NO synthase (iNOS) at the mRNA and protein levels. In contrast, the Δlgt mutant showed little effect under the same condition. Furthermore, S. gordonii wild-type and ΔltaS induced NF-κB activation, STAT1 phosphorylation, and IFN-ß expression, which are important for the induction of iNOS gene expression, with little activation by Δlgt. S. gordonii wild-type and ΔltaS showed an increased adherence and internalization to RAW 264.7 cells compared to Δlgt. In addition, S. gordonii wild-type and ΔltaS, but not Δlgt, substantially increased TLR2 activation while none of these induced NO production in TLR2-deficient macrophages. Triton X-114-extracted lipoproteins from S. gordonii were sufficient to induce NO production. Collectively, we suggest that lipoprotein is an essential cell wall component of S. gordonii to induce NO production in macrophages through TLR2 triggering NF-κB and STAT1 activation.
[Mh] Termos MeSH primário: Proteínas de Bactérias/imunologia
Lipoproteínas/imunologia
Macrófagos/imunologia
Infecções Estreptocócicas/imunologia
Receptor 2 Toll-Like/imunologia
[Mh] Termos MeSH secundário: Animais
Western Blotting
Modelos Animais de Doenças
Macrófagos/metabolismo
Camundongos
Óxido Nítrico/biossíntese
Células RAW 264.7
Reação em Cadeia da Polimerase Via Transcriptase Reversa
Transdução de Sinais/imunologia
Infecções Estreptocócicas/metabolismo
Streptococcus gordonii/imunologia
Receptor 2 Toll-Like/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Lipoproteins); 0 (Tlr2 protein, mouse); 0 (Toll-Like Receptor 2); 31C4KY9ESH (Nitric Oxide)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170911
[Lr] Data última revisão:
170911
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161231
[St] Status:MEDLINE


  9 / 283 MEDLINE  
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[PMID]:27920201
[Au] Autor:Back CR; Sztukowska MN; Till M; Lamont RJ; Jenkinson HF; Nobbs AH; Race PR
[Ad] Endereço:From the School of Oral and Dental Sciences, University of Bristol, Lower Maudlin Street, Bristol BS1 2LY, United Kingdom.
[Ti] Título:The Streptococcus gordonii Adhesin CshA Protein Binds Host Fibronectin via a Catch-Clamp Mechanism.
[So] Source:J Biol Chem;292(5):1538-1549, 2017 Feb 03.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Adherence of bacteria to biotic or abiotic surfaces is a prerequisite for host colonization and represents an important step in microbial pathogenicity. This attachment is facilitated by bacterial adhesins at the cell surface. Because of their size and often elaborate multidomain architectures, these polypeptides represent challenging targets for detailed structural and functional characterization. The multifunctional fibrillar adhesin CshA, which mediates binding to both host molecules and other microorganisms, is an important determinant of colonization by Streptococcus gordonii, an oral commensal and opportunistic pathogen of animals and humans. CshA binds the high-molecular-weight glycoprotein fibronectin (Fn) via an N-terminal non-repetitive region, and this protein-protein interaction has been proposed to promote S. gordonii colonization at multiple sites within the host. However, the molecular details of how these two proteins interact have yet to be established. Here we present a structural description of the Fn binding N-terminal region of CshA, derived from a combination of X-ray crystallography, small angle X-ray scattering, and complementary biophysical methods. In vitro binding studies support a previously unreported two-state "catch-clamp" mechanism of Fn binding by CshA, in which the disordered N-terminal domain of CshA acts to "catch" Fn, via formation of a rapidly assembled but also readily dissociable pre-complex, enabling its neighboring ligand binding domain to tightly clamp the two polypeptides together. This study presents a new paradigm for target binding by a bacterial adhesin, the identification of which will inform future efforts toward the development of anti-adhesive agents that target S. gordonii and related streptococci.
[Mh] Termos MeSH primário: Adesinas Bacterianas/metabolismo
Proteínas de Bactérias/metabolismo
Fibronectinas/metabolismo
Proteínas de Membrana/metabolismo
Streptococcus gordonii/metabolismo
[Mh] Termos MeSH secundário: Adesinas Bacterianas/química
Adesinas Bacterianas/genética
Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Cristalografia por Raios X
Fibronectinas/química
Fibronectinas/genética
Seres Humanos
Proteínas de Membrana/química
Proteínas de Membrana/genética
Ligação Proteica
Domínios Proteicos
Streptococcus gordonii/química
Streptococcus gordonii/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Adhesins, Bacterial); 0 (Bacterial Proteins); 0 (CshA protein, Streptococcus gordonii); 0 (Fibronectins); 0 (Membrane Proteins)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:171025
[Lr] Data última revisão:
171025
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161207
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M116.760975


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[PMID]:27616700
[Au] Autor:Haworth JA; Jenkinson HF; Petersen HJ; Back CR; Brittan JL; Kerrigan SW; Nobbs AH
[Ad] Endereço:School of Oral and Dental Sciences, University of Bristol, Bristol, UK.
[Ti] Título:Concerted functions of Streptococcus gordonii surface proteins PadA and Hsa mediate activation of human platelets and interactions with extracellular matrix.
[So] Source:Cell Microbiol;19(1), 2017 Jan.
[Is] ISSN:1462-5822
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A range of Streptococcus bacteria are able to interact with blood platelets to form a thrombus (clot). Streptococcus gordonii is ubiquitous within the human oral cavity and amongst the common pathogens isolated from subjects with infective endocarditis. Two cell surface proteins, Hsa and Platelet adherence protein A (PadA), in S. gordonii mediate adherence and activation of platelets. In this study, we demonstrate that PadA binds activated platelets and that an NGR (Asparagine-Glycine-Arginine) motif within a 657 amino acid residue N-terminal fragment of PadA is responsible for this, together with two other integrin-like recognition motifs RGT and AGD. PadA also acts in concert with Hsa to mediate binding of S. gordonii to cellular fibronectin and vitronectin, and to promote formation of biofilms. Evidence is presented that PadA and Hsa are each reliant on the other's active presentation on the bacterial cell surface, suggesting cooperativity in functions impacting both colonization and pathogenesis.
[Mh] Termos MeSH primário: Adesinas Bacterianas/metabolismo
Proteínas da Membrana Bacteriana Externa/metabolismo
Proteínas de Transporte/metabolismo
Matriz Extracelular/metabolismo
Interações Hospedeiro-Patógeno
Ativação Plaquetária
Streptococcus gordonii/patogenicidade
Fatores de Virulência/metabolismo
[Mh] Termos MeSH secundário: Aderência Bacteriana
Biofilmes/crescimento & desenvolvimento
Seres Humanos
Proteínas de Membrana/metabolismo
Streptococcus gordonii/crescimento & desenvolvimento
Streptococcus gordonii/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Adhesins, Bacterial); 0 (Bacterial Outer Membrane Proteins); 0 (Carrier Proteins); 0 (Membrane Proteins); 0 (PadA protein, Streptococcus gordonii); 0 (Virulence Factors); 0 (hsa protein, Streptococcus gordonii)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170919
[Lr] Data última revisão:
170919
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160913
[St] Status:MEDLINE
[do] DOI:10.1111/cmi.12667



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