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[PMID]:29391275
[Au] Autor:Yang X; Wang J; Bing G; Bie P; De Y; Lyu Y; Wu Q
[Ad] Endereço:Key Laboratory of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
[Ti] Título:Ortholog-based screening and identification of genes related to intracellular survival.
[So] Source:Gene;651:134-142, 2018 Apr 20.
[Is] ISSN:1879-0038
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Bioinformatics and comparative genomics analysis methods were used to predict unknown pathogen genes based on homology with identified or functionally clustered genes. In this study, the genes of common pathogens were analyzed to screen and identify genes associated with intracellular survival through sequence similarity, phylogenetic tree analysis and the λ-Red recombination system test method. The total 38,952 protein-coding genes of common pathogens were divided into 19,775 clusters. As demonstrated through a COG analysis, information storage and processing genes might play an important role intracellular survival. Only 19 clusters were present in facultative intracellular pathogens, and not all were present in extracellular pathogens. Construction of a phylogenetic tree selected 18 of these 19 clusters. Comparisons with the DEG database and previous research revealed that seven other clusters are considered essential gene clusters and that seven other clusters are associated with intracellular survival. Moreover, this study confirmed that clusters screened by orthologs with similar function could be replaced with an approved uvrY gene and its orthologs, and the results revealed that the usg gene is associated with intracellular survival. The study improves the current understanding of intracellular pathogens characteristics and allows further exploration of the intracellular survival-related gene modules in these pathogens.
[Mh] Termos MeSH primário: Bactérias/genética
Fenômenos Fisiológicos Bacterianos
Células/microbiologia
Genes Bacterianos
[Mh] Termos MeSH secundário: Animais
Proteínas de Bactérias/genética
Proteínas de Bactérias/fisiologia
Células Cultivadas
Genes Essenciais
Interações Hospedeiro-Patógeno
Camundongos
Família Multigênica
Filogenia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins)
[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:180203
[St] Status:MEDLINE


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[PMID]:29458668
[Au] Autor:Al-Ahmad A; Muzafferiy F; Anderson AC; Wölber JP; Ratka-Krüger P; Fretwurst T; Nelson K; Vach K; Hellwig E
[Ad] Endereço:1​Department of Operative Dentistry and Periodontology, Faculty of Medicine, Medical Center - University of Freiburg, Germany.
[Ti] Título:Shift of microbial composition of peri-implantitis-associated oral biofilm as revealed by 16S rRNA gene cloning.
[So] Source:J Med Microbiol;67(3):332-340, 2018 Mar.
[Is] ISSN:1473-5644
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:PURPOSE: Micro-organisms are important triggers of peri-implant inflammation and analysing their diversity is necessary for peri-implantitis treatment. This study aimed to analyse and compare the microbiota associated with individuals with peri-implantitis, as well as clinically healthy implant sites. METHODOLOGY: Subgingival biofilm samples were taken from 10 individuals with peri-implantitis and from at least 1 clinically healthy implant. DNA was extracted and bacterial 16S rRNA genes were amplified using universal primers. After cloning the PCR-products, amplified inserts of positive clones were digested using restriction endonucleases, and the chosen clones were sequenced. The 16S rDNA-sequences were compared to those from the public sequence databases GenBank, EMBL and DDBJ to determine the corresponding taxa. RESULTS: Differing distributions of taxa belonging to the phyla Firmicutes, Bacteroidetes, Fusobacteria, Actinobacteria, Proteobacteria, Synergistetes, Spirochaetae and TM 7 were detected in both the healthy implant (HI) and the peri-implantitis (PI) groups. A significantly higher relative abundance of phylum Bacteroidetes, as well as of the species Fusobacterium nucleatum, were found in the PI group (P<0.05). The putative periodontal red complex (Porphyromonas gingivalis, Tannerella forsythia) was also detected at significantly higher levels in the PI group (P<0.05), whereas the yellow group, as well as the species Veillonella dispar, tended to be associated with the HI group. CONCLUSION: A shift in the healthy subgingival microbiota was shown in peri-implantitis-associated biofilm. Anaerobic Gram-negative periopathogens, including P. gingivalis and T. forsythia, seem to play an important role in peri-implantitis development and should be considered in treatment and prevention strategies.
[Mh] Termos MeSH primário: Bactérias/isolamento & purificação
Biofilmes
Microbiota/genética
Peri-Implantite/microbiologia
RNA Ribossômico 16S/genética
[Mh] Termos MeSH secundário: Idoso
Idoso de 80 Anos ou mais
Bactérias/classificação
Bactérias/genética
Carga Bacteriana
Fenômenos Fisiológicos Bacterianos
Bacteroides/genética
Bacteroides/isolamento & purificação
Feminino
Fusobacterium nucleatum/genética
Fusobacterium nucleatum/isolamento & purificação
Genes de RNAr
Gengiva/microbiologia
Seres Humanos
Masculino
Meia-Idade
Porphyromonas gingivalis/genética
Porphyromonas gingivalis/isolamento & purificação
Prevotella intermedia/genética
Prevotella intermedia/isolamento & purificação
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180221
[St] Status:MEDLINE
[do] DOI:10.1099/jmm.0.000682


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[PMID]:28743239
[Au] Autor:Senneby A; Davies JR; Svensäter G; Neilands J
[Ad] Endereço:Department of Oral and Maxillofacial Radiology, Malmö University, Faculty of Odontology, 205 06, Malmö, SE, Sweden.
[Ti] Título:Acid tolerance properties of dental biofilms in vivo.
[So] Source:BMC Microbiol;17(1):165, 2017 Jul 25.
[Is] ISSN:1471-2180
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The ecological plaque hypothesis explains caries development as the result of the enrichment of acid tolerant bacteria in dental biofilms in response to prolonged periods of low pH. Acid production by an acid tolerant microflora causes demineralisation of tooth enamel and thus, individuals with a greater proportion of acid tolerant bacteria would be expected to be more prone to caries development. Biofilm acid tolerance could therefore be a possible biomarker for caries prediction. However, little is known about the stability of biofilm acid tolerance over time in vivo or the distribution throughout the oral cavity. Therefore the aim of this study was to assess intra-individual differences in biofilm acid-tolerance between different tooth surfaces and inter-individual variation as well as stability of acid tolerance over time. RESULTS: The majority of the adolescents showed low scores for biofilm acid tolerance. In 14 of 20 individuals no differences were seen between the three tooth sites examined. In the remaining six, acid-tolerance at the premolar site differed from one of the other sites. At 51 of 60 tooth sites, acid-tolerance at baseline was unchanged after 1 month. However, acid tolerance values changed over a 1-year period in 50% of the individuals. CONCLUSIONS: Biofilm acid tolerance showed short-term stability and low variation between different sites in the same individual suggesting that the acid tolerance could be a promising biological biomarker candidate for caries prediction. Further evaluation is however needed and prospective clinical trials are called for to evaluate the diagnostic accuracy.
[Mh] Termos MeSH primário: Ácidos/farmacologia
Biofilmes/efeitos dos fármacos
Placa Dentária/microbiologia
[Mh] Termos MeSH secundário: Adolescente
Bactérias/classificação
Bactérias/isolamento & purificação
Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos
Criança
Feminino
Seres Humanos
Masculino
Boca/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acids)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.1186/s12866-017-1074-7


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[PMID]:29302032
[Au] Autor:Mutlu A; Trauth S; Ziesack M; Nagler K; Bergeest JP; Rohr K; Becker N; Höfer T; Bischofs IB
[Ad] Endereço:BioQuant Center of the University of Heidelberg, 69120, Heidelberg, Germany.
[Ti] Título:Phenotypic memory in Bacillus subtilis links dormancy entry and exit by a spore quantity-quality tradeoff.
[So] Source:Nat Commun;9(1):69, 2018 01 04.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Some bacteria, such as Bacillus subtilis, withstand starvation by forming dormant spores that revive when nutrients become available. Although sporulation and spore revival jointly determine survival in fluctuating environments, the relationship between them has been unclear. Here we show that these two processes are linked by a phenotypic "memory" that arises from a carry-over of molecules from the vegetative cell into the spore. By imaging life histories of individual B. subtilis cells using fluorescent reporters, we demonstrate that sporulation timing controls nutrient-induced spore revival. Alanine dehydrogenase contributes to spore memory and controls alanine-induced outgrowth, thereby coupling a spore's revival capacity to the gene expression and growth history of its progenitors. A theoretical analysis, and experiments with signaling mutants exhibiting altered sporulation timing, support the hypothesis that such an intrinsically generated memory leads to a tradeoff between spore quantity and spore quality, which could drive the emergence of complex microbial traits.
[Mh] Termos MeSH primário: Bacillus subtilis/genética
Regulação Bacteriana da Expressão Gênica
Mutação
Esporos Bacterianos/genética
[Mh] Termos MeSH secundário: Alanina Desidrogenase/genética
Alanina Desidrogenase/metabolismo
Algoritmos
Bacillus subtilis/metabolismo
Bacillus subtilis/fisiologia
Fenômenos Fisiológicos Bacterianos/genética
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Modelos Genéticos
Esporos Bacterianos/crescimento & desenvolvimento
Esporos Bacterianos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); EC 1.4.1.1 (Alanine Dehydrogenase)
[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:180106
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02477-1


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[PMID]:29291459
[Au] Autor:Quijada NM; Mann E; Wagner M; Rodríguez-Lázaro D; Hernández M; Schmitz-Esser S
[Ad] Endereço:Institute for Milk Hygiene, University of Veterinary Medicine Vienna, Vienna, Austria; Laboratory of Molecular Biology and Microbiology, Instituto Tecnológico Agrario de Castilla y León, Valladolid, Spain.
[Ti] Título:Autochthonous facility-specific microbiota dominates washed-rind Austrian hard cheese surfaces and its production environment.
[So] Source:Int J Food Microbiol;267:54-61, 2018 Feb 21.
[Is] ISSN:1879-3460
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Cheese ripening involves the succession of complex microbial communities that are responsible for the organoleptic properties of the final products. The food processing environment can act as a source of natural microbial inoculation, especially in traditionally manufactured products. Austrian Vorarlberger Bergkäse (VB) is an artisanal washed-rind hard cheese produced in the western part of Austria without the addition of external ripening cultures. Here, the composition of the bacterial communities present on VB rinds and on different processing surfaces from two ripening cellars was assessed by near full length 16S rRNA gene amplification, cloning and sequencing. Non-inoculated aerobic bacteria dominated all surfaces in this study. VB production conditions (long ripening time, high salt concentration and low temperatures) favor the growth of psychro- and halotolerant bacteria. Several bacterial groups, such as coryneforms, Staphylococcus equorum and Halomonas dominated VB and were also found on most environmental surfaces. Analysis of OTUs shared between different surfaces suggests that VB rind bacteria are inoculated naturally during the ripening from the processing environment and that cheese surfaces exert selective pressure on these communities, as only those bacteria better adapted flourished on VB rinds. This study analyzed VB processing environment microbiota and its relationship with VB rinds for the first time, elucidating that the processing environment and the cheese microbiota should be considered as microbiologically linked ecosystems with the goal of better defining the events that take place during cheese maturation.
[Mh] Termos MeSH primário: Fenômenos Fisiológicos Bacterianos
Queijo/microbiologia
Microbiologia Ambiental
[Mh] Termos MeSH secundário: Áustria
Bactérias/genética
Manipulação de Alimentos
Microbiota/genética
Microbiota/fisiologia
RNA Ribossômico 16S/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Ribosomal, 16S)
[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:180102
[St] Status:MEDLINE


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[PMID]:29288907
[Au] Autor:Lytou AE; Nychas GE; Panagou EZ
[Ad] Endereço:Laboratory of Microbiology and Biotechnology of Foods, Department of Food Science and Human Nutrition, Faculty of Foods, Biotechnology and Development, Agricultural University of Athens, Iera Odos 75, Athens 11855, Greece.
[Ti] Título:Effect of pomegranate based marinades on the microbiological, chemical and sensory quality of chicken meat: A metabolomics approach.
[So] Source:Int J Food Microbiol;267:42-53, 2018 Feb 21.
[Is] ISSN:1879-3460
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Pomegranate juice is a product with enhanced functional properties that could be used as an alternative to traditional marination ingredients and effectively retard microbial growth along with providing an improved sensory result. In this study, two pomegranate based marinades were prepared for the marination of chicken breast fillets and the marinated samples were aerobically stored at 4 and 10°C for 9days. Raw, non-marinated chicken samples were used as control. Levels of total viable counts (TVC), Pseudomonas spp., Brochothrix thermosphacta, Enterobacteriaceae and lactic acid bacteria (LAB) were determined together with sensory assessment to evaluate the evolution of spoilage. The profile of organic acids and volatile compounds was also analyzed during storage. The shelf life of marinated samples was significantly extended compared to control samples at both storage temperatures (e.g., up to 5 and 6days for the pomegranate/lemon marinated samples stored at 4 and 10°C, respectively) as evaluated by both microbiological and sensory analyses. The profile of the organic acids and the volatilome of marinated and control samples were remarkably differentiated according to storage time, microbial load and sensory score. The findings of this study suggest that pomegranate juice could be used as a novel ingredient in marinades to improve the sensory attributes, while prolonging the shelf life of chicken meat.
[Mh] Termos MeSH primário: Conservação de Alimentos/normas
Carne/microbiologia
Metaboloma
Punicaceae/química
[Mh] Termos MeSH secundário: Animais
Bactérias/genética
Fenômenos Fisiológicos Bacterianos
Galinhas
Contagem de Colônia Microbiana
Armazenamento de Alimentos/normas
Seres Humanos
Carne/análise
Carne/normas
Metabolômica
Temperatura Ambiente
Compostos Orgânicos Voláteis/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Volatile Organic Compounds)
[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:171231
[St] Status:MEDLINE


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[PMID]:28449040
[Au] Autor:Yang QE; Walsh TR
[Ad] Endereço:Division of Infection and Immunity, Heath Park Hospital, Cardiff University, Cardiff CF14 4XN, UK.
[Ti] Título:Toxin-antitoxin systems and their role in disseminating and maintaining antimicrobial resistance.
[So] Source:FEMS Microbiol Rev;41(3):343-353, 2017 05 01.
[Is] ISSN:1574-6976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Toxin-antitoxin systems (TAs) are ubiquitous among bacteria and play a crucial role in the dissemination and evolution of antibiotic resistance, such as maintaining multi-resistant plasmids and inducing persistence formation. Generally, activities of the toxins are neutralised by their conjugate antitoxins. In contrast, antitoxins are more liable to degrade under specific conditions such as stress, and free active toxins interfere with essential cellular processes including replication, translation and cell-wall synthesis. TAs have also been shown to be responsible for plasmid maintenance, stress management, bacterial persistence and biofilm formation. We discuss here the recent findings of these multifaceted TAs (type I-VI) and in particular examine the role of TAs in augmenting the dissemination and maintenance of multi-drug resistance in bacteria.
[Mh] Termos MeSH primário: Bactérias/efeitos dos fármacos
Biofilmes/crescimento & desenvolvimento
Farmacorresistência Bacteriana/fisiologia
Plasmídeos/genética
Sistemas Toxina-Antitoxina/fisiologia
[Mh] Termos MeSH secundário: Antibacterianos/farmacologia
Bactérias/genética
Fenômenos Fisiológicos Bacterianos/genética
Toxinas Bacterianas/metabolismo
Parede Celular/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Toxins)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180227
[Lr] Data última revisão:
180227
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170428
[St] Status:MEDLINE
[do] DOI:10.1093/femsre/fux006


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[PMID]:29384621
[Au] Autor:Jasim R; Schneider EK; Han M; Azad MAK; Hussein M; Nowell C; Baker MA; Wang J; Li J; Velkov T
[Ti] Título:A Fresh Shine onCystic Fibrosis Inhalation Therapy: Antimicrobial Synergy of Polymyxin B in Combination with Silver Nanoparticles.
[So] Source:J Biomed Nanotechnol;13(4):447-57, 2017 Apr.
[Is] ISSN:1550-7033
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This in vitro study aimed to investigate the synergistic antibacterial activity of polymyxin B in combination with 2 nm silver nanoparticles (NPs) against Gram-negative pathogens commonly isolated from the cystic fibrosis (CF) lung. The in vitro synergistic activity of polymyxin B with silver NPs was assessed using the checkerboard assay against polymyxinsusceptible and polymyxin-resistant Pseudomonas aeruginosa isolates from the lungs of CF patients. The combination was also examined against the Gram-negative species Haemophilus influenzae, Burkholderia cepacia, Burkholderia pseudomallei, Stenotrophomonas maltophilia, Klebsiella pneumoniae and Acinetobacter baumannii that are less common in the CF lung. The killing kinetics of the polymyxin B-silver NPs combinations was assessed against P. aeruginosa by static time-kill assays over 24 h. Polymyxin B and silver NPs alone were not active against polymyxin-resistant (MIC ≥4 mg/L) P. aeruginosa. Whereas, the combination of a clinically-relevant concentration of polymyxin B (2 mg/L) with silver NPs (4 mg/L) successfully inhibited the growth of polymyxin-resistant P. aeruginosa isolates from CF patients as demonstrated by ≥2 log10 decrease in bacterial count (CFU/mL) after 24 h. Treatment of P. aeruginosa cells with the combination induced cytosolic GFP release and an increase of cellular reactive oxygen species. In the nitrocefin assay, the combination displayed a membrane permeabilizing activity superior to each of the drugs alone. The combination of polymyxin B and silver NPs displays excellent synergistic activity against highly polymyxin-resistant P. aeruginosa and is potentially of considerable clinical utility for the treatment of problematic CF lung infections.
[Mh] Termos MeSH primário: Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos
Fibrose Cística/tratamento farmacológico
Fibrose Cística/microbiologia
Nanopartículas Metálicas/administração & dosagem
Pneumonia Bacteriana/diagnóstico por imagem
Polimixina B/administração & dosagem
Prata/administração & dosagem
[Mh] Termos MeSH secundário: Administração por Inalação
Anti-Infecciosos/administração & dosagem
Anti-Infecciosos/química
Sobrevivência Celular/efeitos dos fármacos
Fibrose Cística/patologia
Difusão
Relação Dose-Resposta a Droga
Combinação de Medicamentos
Sinergismo Farmacológico
Seres Humanos
Nanopartículas Metálicas/química
Pneumonia Bacteriana/microbiologia
Polimixina B/química
Terapia Respiratória/métodos
Prata/química
Resultado do Tratamento
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Infective Agents); 0 (Drug Combinations); 1404-26-8 (Polymyxin B); 3M4G523W1G (Silver)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180201
[St] Status:MEDLINE


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[PMID]:29202309
[Au] Autor:Grimonprez A; Molza A; Laurent MCZ; Mansot JL; Gros O
[Ad] Endereço:Sorbonne Universités, UPMC Univ Paris 06, Univ Antilles Guyane, Univ Nice Sophia Antipolis, CNRS, Evolution Paris Seine-Institut de Biologie Paris Seine (EPS-IBPS), 75005 Paris, France. Electronic address: Adrien.Grimonprez@etu.univ-antilles.fr.
[Ti] Título:Thioautotrophic ectosymbiosis in Pseudovorticella sp., a peritrich ciliate species colonizing wood falls in marine mangrove.
[So] Source:Eur J Protistol;62:43-55, 2018 Feb.
[Is] ISSN:1618-0429
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Ciliates represent a diversified group of protists known to establish symbioses with prokaryotic micro-organisms. They are mainly phagotrophs and symbiotic relationships with bacteria can give them an important advantage in chemosynthetic environments. The aim of this study is to describe the thiotrophic association that occurs between the peritrich ciliate Pseudovorticella sp. and potential sulfur-oxidizing bacteria. Investigations at microscopic scale (LM, SEM, TEM) showed ectosymbiotic bacteria covering the surface of the body of Pseudovorticella sp. According to 16S rDNA phylogenetic analysis, these ectosymbiotic bacteria belong to γ-proteobacteria and are phylogenetically close to the symbiont of the recently described Zoothamnium ignavum, which inhabits shallow-water wood falls. FISH experiments, using symbiont specific probes, clearly indicate that these ectosymbiotic bacteria are also ingested into food vacuoles. Electron lucent granules observed in TEM in the cytoplasm of the ectosymbiotic bacteria have been identified as sulfur granules by Raman microspectrometry analyses. Raman microspectrometry analyses confirmed the thiotrophic nature of this relationship already suggested by the results obtained by TEM and phylogeny. A complete sulfur map was then performed to investigate the sulfur distribution in the zooid. Results show that the relationship between this protist and its bacterial partner is a thiotrophic ectosymbiosis.
[Mh] Termos MeSH primário: Organismos Aquáticos/fisiologia
Fenômenos Fisiológicos Bacterianos
Oligoimenóforos/microbiologia
Simbiose
[Mh] Termos MeSH secundário: Organismos Aquáticos/genética
Bactérias/genética
Bactérias/ultraestrutura
DNA Ribossômico/genética
Oligoimenóforos/genética
Oligoimenóforos/fisiologia
Oligoimenóforos/ultraestrutura
Filogenia
RNA Ribossômico 16S/genética
Madeira/microbiologia
Madeira/parasitologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Ribosomal); 0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171205
[St] Status:MEDLINE


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[PMID]:28457962
[Au] Autor:Khara JS; Obuobi S; Wang Y; Hamilton MS; Robertson BD; Newton SM; Yang YY; Langford PR; Ee PLR
[Ad] Endereço:Department of Pharmacy, National University of Singapore, 18 Science Drive 4, Singapore 117543, Singapore; Section of Paediatrics, Department of Medicine, St Mary's Campus, Imperial College London, London W2 1PG, United Kingdom; MRC Centre for Molecular Bacteriology and Infection, Department of Medi
[Ti] Título:Disruption of drug-resistant biofilms using de novo designed short α-helical antimicrobial peptides with idealized facial amphiphilicity.
[So] Source:Acta Biomater;57:103-114, 2017 Jul 15.
[Is] ISSN:1878-7568
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The escalating threat of antimicrobial resistance has increased pressure to develop novel therapeutic strategies to tackle drug-resistant infections. Antimicrobial peptides have emerged as a promising class of therapeutics for various systemic and topical clinical applications. In this study, the de novo design of α-helical peptides with idealized facial amphiphilicities, based on an understanding of the pertinent features of protein secondary structures, is presented. Synthetic amphiphiles composed of the backbone sequence (X Y Y X ) , where X and X are hydrophobic residues (Leu or Ile or Trp), Y and Y are cationic residues (Lys), and n is the number repeat units (2 or 2.5 or 3), demonstrated potent broad-spectrum antimicrobial activities against clinical isolates of drug-susceptible and multi-drug resistant bacteria. Live-cell imaging revealed that the most selective peptide, (LKKL) , promoted rapid permeabilization of bacterial membranes. Importantly, (LKKL) not only suppressed biofilm growth, but effectively disrupted mature biofilms after only 2h of treatment. The peptides (LKKL) and (WKKW) suppressed the production of LPS-induced pro-inflammatory mediators to levels of unstimulated controls at low micromolar concentrations. Thus, the rational design strategies proposed herein can be implemented to develop potent, selective and multifunctional α-helical peptides to eradicate drug-resistant biofilm-associated infections. STATEMENT OF SIGNIFICANCE: Antimicrobial peptides (AMPs) are increasingly explored as therapeutics for drug-resistant and biofilm-related infections to help expand the size and quality of the current antibiotic pipeline in the face of mounting antimicrobial resistance. Here, synthetic peptides rationally designed based upon principles governing the folding of natural α-helical AMPs, comprising the backbone sequence (X Y Y X ) , and which assemble into α-helical structures with idealized facial amphiphilicity, is presented. These multifunctional peptide amphiphiles demonstrate high bacterial selectivity, promote the disruption of pre-formed drug-resistant biofilms, and effectively neutralize endotoxins at low micromolar concentrations. Overall, the design strategies presented here could provide a useful tool for developing therapeutic peptides with broad-ranging clinical applications from the treatment and prevention of drug-resistant biofilms to the neutralization of bacterial endotoxins.
[Mh] Termos MeSH primário: Peptídeos Catiônicos Antimicrobianos/química
Bactérias/crescimento & desenvolvimento
Biofilmes
Farmacorresistência Bacteriana
Endotoxinas/química
[Mh] Termos MeSH secundário: Fenômenos Fisiológicos Bacterianos
Estrutura Secundária de Proteína
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antimicrobial Cationic Peptides); 0 (Endotoxins)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE



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