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Pesquisa : B03.300.390.400 [Categoria DeCS]
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[PMID]:26825066
[Au] Autor:Gau JS; Lin WP; Kuo LC; Hu MK
[Ti] Título:Nitazoxanide Analogues as Antimicrobial Agents Against Nosocomial Pathogens.
[So] Source:Med Chem;12(6):544-52, 2016.
[Is] ISSN:1875-6638
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The frequent use of antibacterial agents and the exposure of the patients to lifesaving intervention processes are consistently associated with the increased chance of nosocomial infections and the emergence of multidrug resistant microorganisms in the hospital environment. Thus, new antimicrobial agents are of unmet need to treat the severe nosocomial infections caused by these putative pathogens resistant to currently available agents. METHOD: Design, synthesis, and biological evaluation of analogues of nitazoxanide (NTZ), an FDA approved thiazolide antiparasitic, as new antimicrobial agents against nosocomial pathogens were described. The NTZ analogues were rationally explored on the basis of either increasing the electronic resonance effects at the nitrothiazolide moiety or improving the anionic form of the whole NTZ structure. RESULTS: The MICs and MBCs values of these NTZ analogues against prevalent nosocomial pathogens were measured. The benzologous analogues 3a and 4a and p-chlorobenzenesulfonamides 8d and 9d exhibited tremendous antimicrobial activities, which were 100- to 2000-fold more potent than NTZ and ciprofloxacin. CONCLUSION: The results demonstrated that delicate manipulation of the NTZ core structure could lead to promising antimicrobial agents against the nosocomial pathogens.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Tiazóis/farmacologia
[Mh] Termos MeSH secundário: Antibacterianos/síntese química
Ciprofloxacino/farmacologia
Infecção Hospitalar/microbiologia
Bactérias Gram-Negativas/efeitos dos fármacos
Bacilos Gram-Positivos Formadores de Endosporo/efeitos dos fármacos
Testes de Sensibilidade Microbiana
Ftalimidas/síntese química
Ftalimidas/farmacologia
Relação Estrutura-Atividade
Sulfonamidas/síntese química
Sulfonamidas/farmacologia
Tiazóis/síntese química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Phthalimides); 0 (Sulfonamides); 0 (Thiazoles); 5E8K9I0O4U (Ciprofloxacin); SOA12P041N (nitazoxanide)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170704
[Lr] Data última revisão:
170704
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160131
[St] Status:MEDLINE


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[PMID]:26125075
[Au] Autor:Guglielmetti S; Riso P
[Ti] Título:Reply to Conlon et al.
[So] Source:J Nutr;145(5):1031-2, 2015 May.
[Is] ISSN:1541-6100
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Ácido Butírico/química
Fezes/química
Fezes/microbiologia
Bacilos Gram-Positivos Formadores de Endosporo/isolamento & purificação
Lactobacillus
[Mh] Termos MeSH secundário: Feminino
Seres Humanos
Masculino
[Pt] Tipo de publicação:COMMENT; LETTER
[Nm] Nome de substância:
107-92-6 (Butyric Acid)
[Em] Mês de entrada:1506
[Cu] Atualização por classe:150629
[Lr] Data última revisão:
150629
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150701
[St] Status:MEDLINE


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[PMID]:25934666
[Au] Autor:Conlon MA; Bird AR; Clarke JM; Le Leu RK; Christophersen CT; Lockett TJ; Topping DL
[Ad] Endereço:From the CSIRO Food and Nutrition Flagship, Adelaide, Australia (MAC, e-mail: michael.conlon@csiro.au; ARB, JMC, RKLL, CTC, TJL, and DLT).
[Ti] Título:Lowering of large bowel butyrate levels in healthy populations is unlikely to be beneficial.
[So] Source:J Nutr;145(5):1030-1, 2015 May.
[Is] ISSN:1541-6100
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Ácido Butírico/química
Fezes/química
Fezes/microbiologia
Bacilos Gram-Positivos Formadores de Endosporo/isolamento & purificação
Lactobacillus
[Mh] Termos MeSH secundário: Feminino
Seres Humanos
Masculino
[Pt] Tipo de publicação:COMMENT; LETTER
[Nm] Nome de substância:
107-92-6 (Butyric Acid)
[Em] Mês de entrada:1506
[Cu] Atualização por classe:150502
[Lr] Data última revisão:
150502
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150503
[St] Status:MEDLINE
[do] DOI:10.3945/jn.114.209460


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[PMID]:25799047
[Au] Autor:Chung D; Young J; Bomble YJ; Vander Wall TA; Groom J; Himmel ME; Westpheling J
[Ad] Endereço:Department of Genetics, University of Georgia, Athens, Georgia, United States of America; The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America.
[Ti] Título:Homologous expression of the Caldicellulosiruptor bescii CelA reveals that the extracellular protein is glycosylated.
[So] Source:PLoS One;10(3):e0119508, 2015.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Members of the bacterial genus Caldicellulosiruptor are the most thermophilic cellulolytic microbes described with ability to digest lignocellulosic biomass without conventional pretreatment. The cellulolytic ability of different species varies dramatically and correlates with the presence of the multimodular cellulase CelA, which contains both a glycoside hydrolase family 9 endoglucanase and a glycoside hydrolase family 48 exoglucanase known to be synergistic in their activity, connected by three cellulose-binding domains via linker peptides. This architecture exploits the cellulose surface ablation driven by its general cellulase processivity as well as excavates cavities into the surface of the substrate, revealing a novel paradigm for cellulase activity. We recently reported that a deletion of celA in C. bescii had a significant effect on its ability to utilize complex biomass. To analyze the structure and function of CelA and its role in biomass deconstruction, we constructed a new expression vector for C. bescii and were able, for the first time, to express significant quantities of full-length protein in vivo in the native host. The protein, which contains a Histidine tag, was active and excreted from the cell. Expression of CelA protein with and without its signal sequence allowed comparison of protein retained intracellularly to protein transported extracellularly. Analysis of protein in culture supernatants revealed that the extracellular CelA protein is glycosylated whereas the intracellular CelA is not, suggesting that either protein transport is required for this post-translational modification or that glycosylation is required for protein export. The mechanism and role of protein glycosylation in bacteria is poorly understood and the ability to express CelA in vivo in C. bescii will allow the study of the mechanism of protein glycosylation in this thermophile. It will also allow the study of glycosylation of CelA itself and its role in the structure and function of this important enzyme in biomass deconstruction.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Celulase/metabolismo
Celulose/metabolismo
Bacilos Gram-Positivos Formadores de Endosporo/enzimologia
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/isolamento & purificação
Biomassa
Celulase/genética
Celulase/isolamento & purificação
Glicosídeo Hidrolases/metabolismo
Glicosilação
Hidrólise
Processamento de Proteína Pós-Traducional
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Bacterial Proteins); 9004-34-6 (Cellulose); EC 3.2.1.- (Glycoside Hydrolases); EC 3.2.1.4 (CelA endoglucanase); EC 3.2.1.4 (Cellulase)
[Em] Mês de entrada:1602
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150324
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0119508


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Romanha, Alvaro José
Zani, Carlos L
PubMed Central Texto completo
Texto completo SciELO Brasil
[PMID]:25742265
[Au] Autor:Campos FF; Sales Junior PA; Romanha AJ; Araújo MS; Siqueira EP; Resende JM; Alves TM; Martins-Filho OA; Santos VL; Rosa CA; Zani CL; Cota BB
[Ad] Endereço:Departamento de Ciências Biológicas e da Saúde, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, MG, Brasil.
[Ti] Título:Bioactive endophytic fungi isolated from Caesalpinia echinata Lam. (Brazilwood) and identification of beauvericin as a trypanocidal metabolite from Fusarium sp.
[So] Source:Mem Inst Oswaldo Cruz;110(1):65-74, 2015 Feb.
[Is] ISSN:1678-8060
[Cp] País de publicação:Brazil
[La] Idioma:eng
[Ab] Resumo:Aiming to identify new sources of bioactive secondary metabolites, we isolated 82 endophytic fungi from stems and barks of the native Brazilian tree Caesalpinia echinata Lam. (Fabaceae). We tested their ethyl acetate extracts in several in vitro assays. The organic extracts from three isolates showed antibacterial activity against Staphylococcus aureus and Escherichia coli [minimal inhibitory concentration (MIC) 32-64 µg/mL]. One isolate inhibited the growth of Salmonella typhimurium (MIC 64 µg/mL) and two isolates inhibited the growth of Klebsiella oxytoca (MIC 64 µg/mL), Candida albicans and Candida tropicalis (MIC 64-128 µg/mL). Fourteen extracts at a concentration of 20 µg/mL showed antitumour activities against human breast cancer and human renal cancer cells, while two isolates showed anti-tumour activities against human melanoma cancer cells. Six extracts were able to reduce the proliferation of human peripheral blood mononuclear cells, indicating some degree of selective toxicity. Four isolates were able to inhibit Leishmania (Leishmania) amazonensis and one isolate inhibited Trypanosoma cruzi by at least 40% at 20 µg/mL. The trypanocidal extract obtained from Fusarium sp. [KF611679] culture was subjected to bioguided fractionation, which revealed beauvericin as the compound responsible for the observed toxicity of Fusarium sp. to T. cruzi. This depsipeptide showed a half maximal inhibitory concentration of 1.9 µg/mL (2.43 µM) in a T. cruzi cellular culture assay.
[Mh] Termos MeSH primário: Caesalpinia/microbiologia
Depsipeptídeos/farmacologia
Endófitos/isolamento & purificação
Fusarium/isolamento & purificação
Tripanossomicidas/farmacologia
Trypanosoma cruzi/efeitos dos fármacos
[Mh] Termos MeSH secundário: Anti-Infecciosos/isolamento & purificação
Anti-Infecciosos/farmacologia
Candida albicans/efeitos dos fármacos
Linhagem Celular Tumoral/efeitos dos fármacos
Fracionamento Químico
Misturas Complexas
Primers do DNA
Depsipeptídeos/isolamento & purificação
Endófitos/classificação
Enterobacteriaceae/efeitos dos fármacos
Fusarium/metabolismo
Bacilos Gram-Positivos Formadores de Endosporo/efeitos dos fármacos
Seres Humanos
Leishmania/efeitos dos fármacos
Leucócitos Mononucleares/efeitos dos fármacos
Testes de Sensibilidade Microbiana
Pseudomonas aeruginosa/efeitos dos fármacos
Tripanossomicidas/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Infective Agents); 0 (Complex Mixtures); 0 (DNA Primers); 0 (Depsipeptides); 0 (Trypanocidal Agents); 26S048LS2R (beauvericin)
[Em] Mês de entrada:1509
[Cu] Atualização por classe:151119
[Lr] Data última revisão:
151119
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150306
[St] Status:MEDLINE


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[PMID]:25609678
[Au] Autor:Wang Y; Song J; Zhai Y; Zhang C; Gerritsen J; Wang H; Chen X; Li Y; Zhao B; Zhao B; Ruan Z
[Ad] Endereço:Key Laboratory of Microbial Resources (Ministry of Agriculture, PR China), Institute of Agricultural Resources and Regional Planning, CAAS, Beijing 100081, PR China.
[Ti] Título:Romboutsia sedimentorum sp. nov., isolated from an alkaline-saline lake sediment and emended description of the genus Romboutsia.
[So] Source:Int J Syst Evol Microbiol;65(Pt 4):1193-8, 2015 Apr.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A Gram-stain-positive, spore-forming, obligately anaerobic bacterium, designated LAM201(T), was isolated from sediment samples from an alkaline-saline lake located in Daqing oilfield, Daqing City, PR China. Cells of strain LAM201(T) were non-motile and straight or spiral rod-shapes. Strain LAM201(T) was able to utilize glucose, fructose, maltose, trehalose and sorbitol as the sole carbon source. Acetic acid, ethanol, iso-butanoic acid and iso-valeric acid were the main products of glucose fermentation. The major fatty acids of LAM201(T) were C(16 : 0) (26.7%) and C(18 : 0) (11.2%). The main polar lipids were four unknown glycolipids and five unknown phospholipids. The predominant cell-wall sugars were ribose and galactose. The cell-wall peptidoglycan of strain LAM201(T) contained alanine, glycine, glutamic acid and aspartic acid. Sodium sulfite was used as the electron acceptor. The G+C content of the genomic DNA was 32±0.8 mol%, as determined by the T(m) method. Analysis of the 16S rRNA gene sequence indicated that the isolate belonged to the genus Romboutsia and was most closely related to Romboutsia lituseburensis DSM 797(T) and Romboutsia ilealis CRIB(T) with 97.3% and 97.2% similarities, respectively. The DNA-DNA hybridization values between strain LAM201(T) and the two reference strains were 37% and 31%, respectively. On the basis of its phenotypic, phylogenetic and chemotaxonomic characteristics, strain LAM201(T) is suggested to represent a novel species within the genus Romboutsia , for which the name Romboutsia sedimentorum sp. nov. is proposed. The type strain is LAM201(T) ( = ACCC 00717(T) = JCM 19607(T)).
[Mh] Termos MeSH primário: Bacilos Gram-Positivos Formadores de Endosporo/classificação
Lagos/microbiologia
Filogenia
[Mh] Termos MeSH secundário: Bactérias Anaeróbias/classificação
Bactérias Anaeróbias/genética
Bactérias Anaeróbias/isolamento & purificação
Técnicas de Tipagem Bacteriana
Composição de Bases
China
DNA Bacteriano/genética
Ácidos Graxos/química
Sedimentos Geológicos/microbiologia
Glicolipídeos/química
Bacilos Gram-Positivos Formadores de Endosporo/genética
Bacilos Gram-Positivos Formadores de Endosporo/isolamento & purificação
Dados de Sequência Molecular
Hibridização de Ácido Nucleico
Peptidoglicano/química
Fosfolipídeos/química
RNA Ribossômico 16S/genética
Salinidade
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Fatty Acids); 0 (Glycolipids); 0 (Peptidoglycan); 0 (Phospholipids); 0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1510
[Cu] Atualização por classe:150508
[Lr] Data última revisão:
150508
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150123
[St] Status:MEDLINE
[do] DOI:10.1099/ijs.0.000079


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[PMID]:25844469
[Au] Autor:Duda VI; Suzina NE; Polivtseva VN; Gafarov AB; Shorokhova AP; Machulin AV
[Ti] Título:[transversion of cell polarity from Bi- to multipolarity is the mechanism determining multiple spore formation in Anaerobacter polyendosporus PS-1T].
[So] Source:Mikrobiologiia;83(5):575-82, 2014 Sep-Oct.
[Is] ISSN:0026-3656
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:The number of spores formed in a single cell ofAnaerobacterpolyendosporus PS-1T is significantly influenced by the composition of nutrient media. Depending on carbohydrate concentration in synthetic medium, the number of spores may vary from one-two to five-seven. Investigation of spore formation by fluorescence and electron microscopy revealed that on media with 0.5-1.0% glucose or galactose most of the vegetative cells remained rod-shaped after cessation of cell division in the culture. Their nucleoids were localized at cell poles close to the polar site of the cytoplasmic membrane. Forespores were formed at one or both of these poles. A satellite nucleoid (operator) was detected close to each forespore. In the variant with bipolar organization of mother cells only one or two spores per cell were formed. In the second variant of cultivation, when the cells grew at low galactose concentrations (0.1-0.3%), most of the vegetative cells increased in volume and became oval or spherical after cessation of cell division in the culture. Epifluorescence microscopy with nucleic acids-specific fluorochromes (DAPI and acridine orange) revealed the presence of multiple (six to nine) nucleoids in these cells. The nucleoids were located at the cell periphery in close contact with the cytoplasmic membrane. These nucleoids became the centers (poles) for forespore formation. Thus, in the early stationary phase transversion from bipolar to multipolar cells occurred during the early stationary phase. Cessation of cell division combined with continuing replication of the nucleoids resulted in formation on multinuclear cells. The multiplicity of nucleoides and multipolarity of these cells were prerequisites determining endogenous polysporogenesis, occurring as synchronous formation of three to seven twin spores in a number of the oval and spherical cells.
[Mh] Termos MeSH primário: Divisão Celular/fisiologia
Membrana Celular/metabolismo
Galactose/farmacologia
Bacilos Gram-Positivos Formadores de Endosporo/fisiologia
[Mh] Termos MeSH secundário: Membrana Celular/ultraestrutura
Galactose/metabolismo
Bacilos Gram-Positivos Formadores de Endosporo/ultraestrutura
Esporos Bacterianos/crescimento & desenvolvimento
[Pt] Tipo de publicação:ENGLISH ABSTRACT; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
X2RN3Q8DNE (Galactose)
[Em] Mês de entrada:1504
[Cu] Atualização por classe:150406
[Lr] Data última revisão:
150406
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150407
[St] Status:MEDLINE


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[PMID]:25511286
[Au] Autor:Justice NB; Norman A; Brown CT; Singh A; Thomas BC; Banfield JF
[Ad] Endereço:Department of Earth and Planetary Science, University of California, Berkeley, CA 94720, USA. njustice@berkeley.edu.
[Ti] Título:Comparison of environmental and isolate Sulfobacillus genomes reveals diverse carbon, sulfur, nitrogen, and hydrogen metabolisms.
[So] Source:BMC Genomics;15:1107, 2014 Dec 15.
[Is] ISSN:1471-2164
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Bacteria of the genus Sulfobacillus are found worldwide as members of microbial communities that accelerate sulfide mineral dissolution in acid mine drainage environments (AMD), acid-rock drainage environments (ARD), as well as in industrial bioleaching operations. Despite their frequent identification in these environments, their role in biogeochemical cycling is poorly understood. RESULTS: Here we report draft genomes of five species of the Sulfobacillus genus (AMDSBA1-5) reconstructed by cultivation-independent sequencing of biofilms sampled from the Richmond Mine (Iron Mountain, CA). Three of these species (AMDSBA2, AMDSBA3, and AMDSBA4) have no cultured representatives while AMDSBA1 is a strain of S. benefaciens, and AMDSBA5 a strain of S. thermosulfidooxidans. We analyzed the diversity of energy conservation and central carbon metabolisms for these genomes and previously published Sulfobacillus genomes. Pathways of sulfur oxidation vary considerably across the genus, including the number and type of subunits of putative heterodisulfide reductase complexes likely involved in sulfur oxidation. The number and type of nickel-iron hydrogenase proteins varied across the genus, as does the presence of different central carbon pathways. Only the AMDSBA3 genome encodes a dissimilatory nitrate reducatase and only the AMDSBA5 and S. thermosulfidooxidans genomes encode assimilatory nitrate reductases. Within the genus, AMDSBA4 is unusual in that its electron transport chain includes a cytochrome bc type complex, a unique cytochrome c oxidase, and two distinct succinate dehydrogenase complexes. CONCLUSIONS: Overall, the results significantly expand our understanding of carbon, sulfur, nitrogen, and hydrogen metabolism within the Sulfobacillus genus.
[Mh] Termos MeSH primário: Genoma Bacteriano
Bacilos Gram-Positivos Formadores de Endosporo/genética
[Mh] Termos MeSH secundário: Proteínas de Bactérias/classificação
Proteínas de Bactérias/genética
Carbono/metabolismo
Metabolismo Energético/genética
Bacilos Gram-Positivos Formadores de Endosporo/isolamento & purificação
Hidrogênio/metabolismo
Nitrogênio/metabolismo
Oxirredução
Filogenia
RNA Ribossômico 16S/química
RNA Ribossômico 16S/genética
Proteínas Ribossômicas/classificação
Proteínas Ribossômicas/genética
Análise de Sequência de RNA
Enxofre/metabolismo
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (RNA, Ribosomal, 16S); 0 (Ribosomal Proteins); 70FD1KFU70 (Sulfur); 7440-44-0 (Carbon); 7YNJ3PO35Z (Hydrogen); N762921K75 (Nitrogen)
[Em] Mês de entrada:1602
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:141217
[St] Status:MEDLINE
[do] DOI:10.1186/1471-2164-15-1107


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[PMID]:25359777
[Au] Autor:Little DJ; Bamford NC; Pokrovskaya V; Robinson H; Nitz M; Howell PL
[Ad] Endereço:From the Program in Molecular Structure and Function, Research Institute, The Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada, Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
[Ti] Título:Structural basis for the De-N-acetylation of Poly-ß-1,6-N-acetyl-D-glucosamine in Gram-positive bacteria.
[So] Source:J Biol Chem;289(52):35907-17, 2014 Dec 26.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Exopolysaccharides are required for the development and integrity of biofilms produced by a wide variety of bacteria. In staphylococci, partial de-N-acetylation of the exopolysaccharide poly-ß-1,6-N-acetyl-d-glucosamine (PNAG) by the extracellular protein IcaB is required for biofilm formation. To understand the molecular basis for PNAG de-N-acetylation, the structure of IcaB from Ammonifex degensii (IcaBAd) has been determined to 1.7 Å resolution. The structure of IcaBAd reveals a (ß/α)7 barrel common to the family four carbohydrate esterases (CE4s) with the canonical motifs circularly permuted. The metal dependence of IcaBAd is similar to most CE4s showing the maximum rates of de-N-acetylation with Ni(2+), Co(2+), and Zn(2+). From docking studies with ß-1,6-GlcNAc oligomers and structural comparison to PgaB from Escherichia coli, the Gram-negative homologue of IcaB, we identify Arg-45, Tyr-67, and Trp-180 as key residues for PNAG binding during catalysis. The absence of these residues in PgaB provides a rationale for the requirement of a C-terminal domain for efficient deacetylation of PNAG in Gram-negative species. Mutational analysis of conserved active site residues suggests that IcaB uses an altered catalytic mechanism in comparison to other characterized CE4 members. Furthermore, we identified a conserved surface-exposed hydrophobic loop found only in Gram-positive homologues of IcaB. Our data suggest that this loop is required for membrane association and likely anchors IcaB to the membrane during polysaccharide biosynthesis. The work presented herein will help guide the design of IcaB inhibitors to combat biofilm formation by staphylococci.
[Mh] Termos MeSH primário: Amidoidrolases/química
Proteínas de Bactérias/química
Bacilos Gram-Positivos Formadores de Endosporo/enzimologia
beta-Glucanas/química
[Mh] Termos MeSH secundário: Acetilação
Sequência de Aminoácidos
Domínio Catalítico
Sequência Conservada
Cristalografia por Raios X
Interações Hidrofóbicas e Hidrofílicas
Simulação de Acoplamento Molecular
Dados de Sequência Molecular
Ligação Proteica
Estrutura Secundária de Proteína
Zinco/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (beta-Glucans); 0 (poly-N-acetyl-1-6-glucosamine); EC 3.5.- (Amidohydrolases); EC 3.5.1.- (polysaccharide deacetylase); J41CSQ7QDS (Zinc)
[Em] Mês de entrada:1504
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:141101
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M114.611400


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[PMID]:25332478
[Au] Autor:Ferrario C; Taverniti V; Milani C; Fiore W; Laureati M; De Noni I; Stuknyte M; Chouaia B; Riso P; Guglielmetti S
[Ad] Endereço:Department of Food, Environmental and Nutritional Sciences (DeFENS), Università degli Studi di Milano, Milan, Italy;
[Ti] Título:Modulation of fecal Clostridiales bacteria and butyrate by probiotic intervention with Lactobacillus paracasei DG varies among healthy adults.
[So] Source:J Nutr;144(11):1787-96, 2014 Nov.
[Is] ISSN:1541-6100
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The modulation of gut microbiota is considered to be the first target to establish probiotic efficacy in a healthy population. OBJECTIVE: This study was conducted to determine the impact of a probiotic on the intestinal microbial ecology of healthy volunteers. METHODS: High-throughput 16S ribosomal RNA gene sequencing was used to characterize the fecal microbiota in healthy adults (23-55 y old) of both sexes, before and after 4 wk of daily consumption of a capsule containing at least 24 billion viable Lactobacillus paracasei DG cells, according to a randomized, double-blind, crossover placebo-controlled design. RESULTS: Probiotic intake induced an increase in Proteobacteria (P = 0.006) and in the Clostridiales genus Coprococcus (P = 0.009), whereas the Clostridiales genus Blautia (P = 0.036) was decreased; a trend of reduction was also observed for Anaerostipes (P = 0.05) and Clostridium (P = 0.06). We also found that the probiotic effect depended on the initial butyrate concentration. In fact, participants with butyrate >100 mmol/kg of wet feces had a mean butyrate reduction of 49 ± 21% and a concomitant decrease in the sum of 6 Clostridiales genera, namely Faecalibacterium, Blautia, Anaerostipes, Pseudobutyrivibrio, Clostridium, and Butyrivibrio (P = 0.021), after the probiotic intervention. In contrast, in participants with initial butyrate concentrations <25 mmol/kg of wet feces, the probiotic contributed to a 329 ± 255% (mean ± SD) increment in butyrate concomitantly with an ∼55% decrease in Ruminococcus (P = 0.016) and a 150% increase in an abundantly represented unclassified Bacteroidales genus (P = 0.05). CONCLUSIONS: The intake of L. paracasei DG increased the Blautia:Coprococcus ratio, which, according to the literature, can potentially confer a health benefit on the host. The probiotic impact on the microbiota and on short-chain fatty acids, however, seems to strictly depend on the initial characteristics of the intestinal microbial ecosystem. In particular, fecal butyrate concentrations could represent an important biomarker for identifying subjects who may benefit from probiotic treatment. This trial was registered at www.controlled-trials.com/isrctn as ISRCTN56945491.
[Mh] Termos MeSH primário: Ácido Butírico/química
Fezes/química
Fezes/microbiologia
Bacilos Gram-Positivos Formadores de Endosporo/isolamento & purificação
Lactobacillus
[Mh] Termos MeSH secundário: Adulto
Ácido Butírico/metabolismo
Método Duplo-Cego
Feminino
Bacilos Gram-Positivos Formadores de Endosporo/classificação
Seres Humanos
Masculino
Meia-Idade
Probióticos
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
107-92-6 (Butyric Acid)
[Em] Mês de entrada:1412
[Cu] Atualização por classe:150629
[Lr] Data última revisão:
150629
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:141022
[St] Status:MEDLINE
[do] DOI:10.3945/jn.114.197723



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