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[PMID]:28840795
[Au] Autor:Hurtado-Ortiz R; Nazimoudine A; Criscuolo A; Hugon P; Mornico D; Brisse S; Bizet C; Clermont D
[Ad] Endereço:2​CRBIP-Centre de Ressources Biologiques, Institut Pasteur, Paris, France 1​CIP-Collection of Institut Pasteur, Institut Pasteur, Paris, France.
[Ti] Título:Psychrobacter pasteurii and Psychrobacter piechaudii sp. nov., two novel species within the genus Psychrobacter.
[So] Source:Int J Syst Evol Microbiol;67(9):3192-3197, 2017 Sep.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Six Gram-negative, non-motile, non-spore-forming, non-pigmented, oxidase- and catalase-positive bacterial strains were deposited in 1972, in the Collection of the Institut Pasteur (CIP), Paris, France. The strains, previously identified as members of the genus Moraxella on the basis of their phenotypic and biochemical characteristics, were placed within the genus Psychrobacter based on the results from comparative 16S rRNA gene sequence studies. Their closest phylogenetic relatives were Psychrobacter sanguinis CIP 110993T, Psychrobacter phenylpyruvicus CIP 82.27T and Psychrobacter lutiphocae CIP 110018T. The DNA G+C contents were between 42.1 and 42.7 mol%. The predominant fatty acids were C18 : 1ω9c, C16 : 0, C12 : 0 3-OH, and C18 : 0. Average nucleotide identity between the six strains and their closest phylogenetic relatives, as well as their phenotypic characteristics, supported the assignment of these strains to two novel species within the genus Psychrobacter. The proposed names for these strains are Psychrobacter pasteurii sp. nov., for which the type strain is A1019T (=CIP 110853T=CECT 9184T), and Psychrobacter piechaudii sp. nov., for which the type strain is 1232T (=CIP110854T=CECT 9185T).
[Mh] Termos MeSH primário: Filogenia
Psychrobacter/classificação
[Mh] Termos MeSH secundário: Técnicas de Tipagem Bacteriana
Composição de Bases
DNA Bacteriano/genética
DNA Ribossômico/genética
Ácidos Graxos/química
França
Psychrobacter/genética
Psychrobacter/isolamento & purificação
RNA Ribossômico 16S/genética
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (DNA, Ribosomal); 0 (Fatty Acids); 0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170920
[Lr] Data última revisão:
170920
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170826
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.002065


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[PMID]:28284313
[Au] Autor:Acevedo JP; Reetz MT; Asenjo JA; Parra LP
[Ad] Endereço:Facultad de Medicina y Facultad de Ingeniería y Ciencias Aplicadas, Universidad de los Andes, San Carlos de Apoquindo, 2200 Santiago, Chile.
[Ti] Título:One-step combined focused epPCR and saturation mutagenesis for thermostability evolution of a new cold-active xylanase.
[So] Source:Enzyme Microb Technol;100:60-70, 2017 May.
[Is] ISSN:1879-0909
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Enzymes active at low temperature are of great interest for industrial bioprocesses due to their high efficiency at a low energy cost. One of the particularities of naturally evolved cold-active enzymes is their increased enzymatic activity at low temperature, however the low thermostability presented in this type of enzymes is still a major drawback for their application in biocatalysis. Directed evolution of cold-adapted enzymes to a more thermostable version, appears as an attractive strategy to fulfill the stability and activity requirements for the industry. This paper describes the recombinant expression and characterization of a new and highly active cold-adapted xylanase from the GH-family 10 (Xyl-L), and the use of a novel one step combined directed evolution technique that comprises saturation mutagenesis and focused epPCR as a feasible semi-rational strategy to improve the thermostability. The Xyl-L enzyme was cloned from a marine-Antarctic bacterium, Psychrobacter sp. strain 2-17, recombinantly expressed in E. coli strain BL21(DE3) and characterized enzymatically. Molecular dynamic simulations using a homology model of the catalytic domain of Xyl-L were performed to detect flexible regions and residues, which are considered to be the possible structural elements that define the thermolability of this enzyme. Mutagenic libraries were designed in order to stabilize the protein introducing mutations in some of the flexible regions and residues identified. Twelve positive mutant clones were found to improve the T value of the enzyme, in some cases without affecting the activity at 25°C. The best mutant showed a 4.3°C increase in its T . The efficiency of the directed evolution approach can also be expected to work in the protein engineering of stereoselectivity.
[Mh] Termos MeSH primário: Evolução Molecular Direcionada/métodos
Endo-1,4-beta-Xilanases/genética
Endo-1,4-beta-Xilanases/metabolismo
Mutagênese
Reação em Cadeia da Polimerase/métodos
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Biocatálise
Clonagem Molecular
Temperatura Baixa
Endo-1,4-beta-Xilanases/química
Estabilidade Enzimática/genética
Genes Bacterianos
Modelos Moleculares
Simulação de Dinâmica Molecular
Engenharia de Proteínas/métodos
Psychrobacter/enzimologia
Psychrobacter/genética
Homologia Estrutural de Proteína
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); EC 3.2.1.8 (Endo-1,4-beta Xylanases)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170906
[Lr] Data última revisão:
170906
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170313
[St] Status:MEDLINE


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[PMID]:28092443
[Au] Autor:Stroek R; Ge Y; Talbot PD; Glok MK; Bernas KE; Thomson CM; Gould ER; Alphey MS; Liu H; Florence GJ; Naismith JH; da Silva RG
[Ad] Endereço:School of Engineering and Applied Science, Rotterdam University of Applied Science , G. J. de Jonghweg 4-6, 3015 GG Rotterdam, The Netherlands.
[Ti] Título:Kinetics and Structure of a Cold-Adapted Hetero-Octameric ATP Phosphoribosyltransferase.
[So] Source:Biochemistry;56(5):793-803, 2017 Feb 07.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Adenosine 5'-triphosphate phosphoribosyltransferase (ATPPRT) catalyzes the first step in histidine biosynthesis, the condensation of ATP and 5-phospho-α-d-ribosyl-1-pyrophosphate to generate N -(5-phospho-ß-d-ribosyl)-ATP and inorganic pyrophosphate. The enzyme is allosterically inhibited by histidine. Two forms of ATPPRT, encoded by the hisG gene, exist in nature, depending on the species. The long form, HisG , is a single polypeptide chain with catalytic and regulatory domains. The short form, HisG , lacks a regulatory domain and cannot bind histidine. HisG instead is found in complex with a regulatory protein, HisZ, constituting the ATPPRT holoenzyme. HisZ triggers HisG catalytic activity while rendering it sensitive to allosteric inhibition by histidine. Until recently, HisG was thought to be catalytically inactive without HisZ. Here, recombinant HisG and HisZ from the psychrophilic bacterium Psychrobacter arcticus were independently overexpressed and purified. The crystal structure of P. arcticus ATPPRT was determined at 2.34 Å resolution, revealing an equimolar HisG -HisZ hetero-octamer. Steady-state kinetics indicate that both the ATPPRT holoenzyme and HisG are catalytically active. Surprisingly, HisZ confers only a modest 2-4-fold increase in k . Reaction profiles for both enzymes cannot be distinguished by P nuclear magnetic resonance, indicating that the same reaction is catalyzed. The temperature dependence of k shows deviation from Arrhenius behavior at 308 K with the holoenzyme. Interestingly, such deviation is detected only at 313 K with HisG . Thermal denaturation by CD spectroscopy resulted in T 's of 312 and 316 K for HisZ and HisG , respectively, suggesting that HisZ renders the ATPPRT complex more thermolabile. This is the first characterization of a psychrophilic ATPPRT.
[Mh] Termos MeSH primário: ATP Fosforribosiltransferase/química
Aminoacil-tRNA Sintetases/química
Proteínas de Bactérias/química
Histidina/química
Proteínas de Transporte de Monossacarídeos/química
Psychrobacter/enzimologia
[Mh] Termos MeSH secundário: ATP Fosforribosiltransferase/genética
ATP Fosforribosiltransferase/metabolismo
Aclimatação
Trifosfato de Adenosina/análogos & derivados
Trifosfato de Adenosina/química
Trifosfato de Adenosina/metabolismo
Regulação Alostérica
Aminoacil-tRNA Sintetases/genética
Aminoacil-tRNA Sintetases/metabolismo
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Temperatura Baixa
Cristalografia por Raios X
Difosfatos/química
Difosfatos/metabolismo
Estabilidade Enzimática
Escherichia coli/genética
Escherichia coli/metabolismo
Expressão Gênica
Histidina/biossíntese
Isoenzimas/química
Isoenzimas/genética
Isoenzimas/metabolismo
Cinética
Modelos Moleculares
Proteínas de Transporte de Monossacarídeos/genética
Proteínas de Transporte de Monossacarídeos/metabolismo
Fosforribosil Pirofosfato/química
Fosforribosil Pirofosfato/metabolismo
Domínios Proteicos
Multimerização Proteica
Estrutura Secundária de Proteína
Psychrobacter/genética
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Termodinâmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Diphosphates); 0 (HisG protein, bacteria); 0 (Isoenzymes); 0 (Monosaccharide Transport Proteins); 0 (Recombinant Proteins); 1110-99-2 (phosphoribosyladenosine triphosphate); 4E862E7GRQ (diphosphoric acid); 4QD397987E (Histidine); 7540-64-9 (Phosphoribosyl Pyrophosphate); 8L70Q75FXE (Adenosine Triphosphate); EC 2.4.2.17 (ATP Phosphoribosyltransferase); EC 6.1.1.- (Amino Acyl-tRNA Synthetases)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170515
[Lr] Data última revisão:
170515
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170117
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.6b01138


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[PMID]:28062189
[Au] Autor:Makled SO; Hamdan AM; El-Sayed AM; Hafez EE
[Ad] Endereço:Oceanography Department, Faculty of Science, Alexandria University, 21511, Alexandria, Egypt.
[Ti] Título:Evaluation of marine psychrophile, Psychrobacter namhaensis SO89, as a probiotic in Nile tilapia (Oreochromis niloticus) diets.
[So] Source:Fish Shellfish Immunol;61:194-200, 2017 Feb.
[Is] ISSN:1095-9947
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Marine environment represents a promising source of new, unconventional bioactive compounds with health-promoting abilities, which can be used as food supplements. The present study was carried out to evaluate the efficacy of marine Psychrobacter namhaensis SO89 on growth performance and immune response of Nile tilapia (Oreochromis niloticus). P. namhaensis were isolated from marine environments and phylogenetically identified by 16S rRNA gene sequences. The bacterial isolate was incorporated in Nile tilapia diets (30% crude protein) at three concentrations (0.0, 0.5 and 1.0%; w/w) (designated as T , T and T , respectively), which were equivalent to 0.0, 2.8 × 10 and 5.6 × 10 CFU g diet, respectively. The diets were fed to Nile tilapia fingerlings (4.58 ± 0.14 g average weight) at a daily rate of 3% of their live body weights (BW), 3 times a day for 50 days. The best growth rates and feed utilization efficiency were obtained at 0.5% P. namhaensis SO89 concentration. Hematocrit (Ht%), hemoglobin (Hb%), erythrocytes (RBC) and total leukocyte (WBCs) values were significantly higher in P. namhaensis SO89- fed groups than in the control group. Similarly, immunoglobulin M (IgM), alternative complement hemolysis (ACH50), phagocytic and lysozyme activities significantly increased following dietary P. namhaensis SO89 supplementation at 0.5% concentration compared to the control group. The expression of IL-4 and IL-12 genes was also significantly up-regulated in P. namhaensis SO89-treated groups up to 0.5% concentration. Increasing bacterial concentration to 1% resulted in a significant decrease in fish performance and immune response. The present results suggest that marine psychrotolerant (Psychrobacter namhaensis) can be considered as a novel feed additive in Nile tilapia feeds.
[Mh] Termos MeSH primário: Ciclídeos/crescimento & desenvolvimento
Ciclídeos/imunologia
Imunidade Inata
Probióticos/farmacologia
Psychrobacter/química
[Mh] Termos MeSH secundário: Ração Animal/análise
Animais
Análise Química do Sangue/veterinária
Dieta/veterinária
Suplementos Nutricionais/análise
Relação Dose-Resposta a Droga
Testes Hematológicos/veterinária
Psychrobacter/classificação
Psychrobacter/genética
RNA Bacteriano/genética
RNA Bacteriano/metabolismo
RNA Ribossômico 16S/genética
RNA Ribossômico 16S/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Bacterial); 0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170410
[Lr] Data última revisão:
170410
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170108
[St] Status:MEDLINE


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[PMID]:27750393
[Au] Autor:Koh HY; Park H; Lee JH; Han SJ; Sohn YC; Lee SG
[Ad] Endereço:Unit of Polar Genomics Korea Polar Research Institute, Incheon, South Korea.
[Ti] Título:Proteomic and transcriptomic investigations on cold-responsive properties of the psychrophilic Antarctic bacterium Psychrobacter sp. PAMC 21119 at subzero temperatures.
[So] Source:Environ Microbiol;19(2):628-644, 2017 Feb.
[Is] ISSN:1462-2920
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Psychrobacter sp. PAMC 21119, isolated from Antarctic permafrost soil, grows and proliferates at subzero temperatures. However, its major mechanism of cold adaptation regulation remains poorly understood. We investigated the transcriptomic and proteomic responses of this species to cold temperatures by comparing profiles at -5°C and 20°C to understand how extreme microorganisms survive under subzero conditions. We found a total of 2,906 transcripts and 584 differentially expressed genes (≥ twofold, P <0.005) by RNA-seq. Genes for translation, ribosomal structure and biogenesis were upregulated, and lipid transport and metabolism was downregulated at low temperatures. A total of 60 protein spots (≥ 1.8 fold, P < 0.005) showed differential expression on two-dimensional gel electrophoresis and the proteins were identified by mass spectrometry. The most prominent upregulated proteins in response to cold were involved in metabolite transport, protein folding and membrane fluidity. Proteins involved in energy production and conversion, and heme protein synthesis were downregulated. Moreover, isoform exchange of cold-shock proteins was detected at both temperatures. Interestingly, pathways for acetyl-CoA metabolism, putrescine synthesis and amino acid metabolism were upregulated. This study highlights some of the strategies and different physiological states that Psychrobacter sp. PAMC 21119 has developed to adapt to the cold environment in Antarctica.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Proteínas e Peptídeos de Choque Frio/metabolismo
Temperatura Baixa
Proteômica
Psychrobacter/fisiologia
Transcriptoma
[Mh] Termos MeSH secundário: Acetilcoenzima A/metabolismo
Regiões Antárticas
Proteínas de Bactérias/genética
Proteínas e Peptídeos de Choque Frio/genética
Regulação Bacteriana da Expressão Gênica
Dobramento de Proteína
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Cold Shock Proteins and Peptides); 72-89-9 (Acetyl Coenzyme A)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161018
[St] Status:MEDLINE
[do] DOI:10.1111/1462-2920.13578


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[PMID]:27609593
[Au] Autor:Zachariah S; Kumari P; Das SK
[Ad] Endereço:Institute of Life Sciences, Department of Biotechnology, Nalco Square, Bhubaneswar-751 023, India.
[Ti] Título:Psychrobacter pocilloporae sp. nov., isolated from a coral, Pocillopora eydouxi.
[So] Source:Int J Syst Evol Microbiol;66(12):5091-5098, 2016 Dec.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Two closely related aerobic, Gram-stain-negative, rod-shaped bacteria (S6-60T and S6-67) were isolated from the mucus of the coral, Pocilloporaeydouxi, from the Andaman Sea, India. Heterotrophic growth on marine agar was observed at 4-37 °C and at pH 6.5-10.0; optimum growth occurred at 25-30 °C and at pH 7-9. 16S rRNA gene sequence analysis confirmed that the isolates belong to the genus Psychrobacter; the two isolates shared more than 99.5 % pairwise sequence similarity. Strain S6-60T showed a maximum 16S rRNA similarity of 98.92 % with Psychrobacter pacificensis DSM 23406T. DNA-DNA homology between the two isolates, S6-60T and S6-67, was above 90 %, whereas strain S6-60T showed less than 70 % homology with closely related type species. The DNA G+C content was 47.7 mol%. It contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and phospholipid as the major polar lipids. C10 : 0, C12 : 0 3OH, C16 : 0, C18 : 1ω9c, C17 : 1ω8c and C16 : 1ω7c were found to be the predominant fatty acids. Based on a polyphasic analysis, the isolates (S6-60T and S6-67) represent a novel species of the genus Psychrobacter for which the name Psychrobacter pocilloporae sp. nov. is proposed with S6-60T(=JCM 31058T=LMG 29157T) as the type strain.
[Mh] Termos MeSH primário: Antozoários/microbiologia
Filogenia
Psychrobacter/classificação
[Mh] Termos MeSH secundário: Animais
Técnicas de Tipagem Bacteriana
Composição de Bases
DNA Bacteriano/genética
Ácidos Graxos/química
Índia
Hibridização de Ácido Nucleico
Fosfolipídeos/química
Psychrobacter/genética
Psychrobacter/isolamento & purificação
RNA Ribossômico 16S/genética
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Fatty Acids); 0 (Phospholipids); 0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160910
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.001476


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[PMID]:27417227
[Au] Autor:Buonocore F; Bernini C; Coscia MR; Giacomelli S; de Pascale D; Randelli E; Stocchi V; Scapigliati G
[Ad] Endereço:Università della Tuscia, Dipartimento per l'Innovazione Biologica, Agroalimentare e Forestale, Viterbo, Italy.
[Ti] Título:Immune response of the Antarctic teleost Trematomus bernacchii to immunization with Psychrobacter sp. (TAD1).
[So] Source:Fish Shellfish Immunol;56:192-198, 2016 Sep.
[Is] ISSN:1095-9947
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Adult Trematomus bernacchii have been immunized intraperitoneally with heat-killed cells of the Antarctic marine bacterium Psychrobacter sp. (TAD1) up to 60 days. After immunizations and sampling at various times, fish sera were tested for specific IgM by ELISA, and different tissues (head kidney and spleen) were investigated for transcription of master genes of the acquired immune response (IgM, IgT, TRß, TRγ). Results from ELISA assays showed a time-dependent induction of specific serum anti-TAD1 IgM, and western blot analysis of TAD1 lysates probed with fish sera revealed enhanced immunoreactivity in immunized animals compared to controls. Quantitative PCR analysis of transcripts coding for IgM, IgT, TRß, TRγ was performed in T. bernacchii tissues to assess basal expression, and then on cDNAs of cells from head kidney and spleen of fish injected for 8, 24, and 72 h with inactivated TAD1. The results showed a differential basal expression of transcripts in the examined tissues, and a time-dependent strong up-regulation of IgT, TRß, TRγ genes upon in vivo stimulation with TAD1. These results represent a first in vivo study on the mounting of a specific immune response in an Antarctic teleost species.
[Mh] Termos MeSH primário: Doenças dos Peixes/imunologia
Imunidade Humoral
Imunização/veterinária
Infecções por Moraxellaceae/veterinária
Perciformes
Psychrobacter/imunologia
[Mh] Termos MeSH secundário: Animais
Anticorpos Antibacterianos/sangue
Ensaio de Imunoadsorção Enzimática/veterinária
Doenças dos Peixes/genética
Doenças dos Peixes/microbiologia
Proteínas de Peixes/genética
Proteínas de Peixes/metabolismo
Rim Cefálico/imunologia
Imunoglobulina M/sangue
Injeções Intraperitoneais/veterinária
Infecções por Moraxellaceae/genética
Infecções por Moraxellaceae/imunologia
Infecções por Moraxellaceae/microbiologia
Baço/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Bacterial); 0 (Fish Proteins); 0 (Immunoglobulin M)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170812
[Lr] Data última revisão:
170812
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160716
[St] Status:MEDLINE


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[PMID]:27128927
[Au] Autor:Tedesco P; Maida I; Palma Esposito F; Tortorella E; Subko K; Ezeofor CC; Zhang Y; Tabudravu J; Jaspars M; Fani R; de Pascale D
[Ad] Endereço:Institute of Protein Biochemistry, National Research Council, Via P. Castellino, 111, I-80131 Naples, Italy. p.tedesco@ibp.cnr.it.
[Ti] Título:Antimicrobial Activity of Monoramnholipids Produced by Bacterial Strains Isolated from the Ross Sea (Antarctica).
[So] Source:Mar Drugs;14(5), 2016 Apr 26.
[Is] ISSN:1660-3397
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Microorganisms living in extreme environments represent a huge reservoir of novel antimicrobial compounds and possibly of novel chemical families. Antarctica is one of the most extraordinary places on Earth and exhibits many distinctive features. Antarctic microorganisms are well known producers of valuable secondary metabolites. Specifically, several Antarctic strains have been reported to inhibit opportunistic human pathogens strains belonging to Burkholderia cepacia complex (Bcc). Herein, we applied a biodiscovery pipeline for the identification of anti-Bcc compounds. Antarctic sub-sea sediments were collected from the Ross Sea, and used to isolate 25 microorganisms, which were phylogenetically affiliated to three bacterial genera (Psychrobacter, Arthrobacter, and Pseudomonas) via sequencing and analysis of 16S rRNA genes. They were then subjected to a primary cell-based screening to determine their bioactivity against Bcc strains. Positive isolates were used to produce crude extracts from microbial spent culture media, to perform the secondary screening. Strain Pseudomonas BNT1 was then selected for bioassay-guided purification employing SPE and HPLC. Finally, LC-MS and NMR structurally resolved the purified bioactive compounds. With this strategy, we achieved the isolation of three rhamnolipids, two of which were new, endowed with high (MIC < 1 µg/mL) and unreported antimicrobial activity against Bcc strains.
[Mh] Termos MeSH primário: Antibacterianos/química
Antibacterianos/farmacologia
Lipídeos/química
Lipídeos/farmacologia
[Mh] Termos MeSH secundário: Regiões Antárticas
Arthrobacter/química
Arthrobacter/genética
Complexo Burkholderia cepacia/química
Complexo Burkholderia cepacia/genética
Genes Bacterianos/genética
Filogenia
Pseudomonas/química
Pseudomonas/genética
Psychrobacter/química
Psychrobacter/genética
RNA Ribossômico 16S/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Lipids); 0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170512
[Lr] Data última revisão:
170512
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160430
[St] Status:MEDLINE


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[PMID]:27033516
[Au] Autor:Hu W; Zhang Q; Tian T; Li D; Cheng G; Mu J; Wu Q; Niu F; An L; Feng H
[Ad] Endereço:Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China.
[Ti] Título:Characterization of the prokaryotic diversity through a stratigraphic permafrost core profile from the Qinghai-Tibet Plateau.
[So] Source:Extremophiles;20(3):337-49, 2016 May.
[Is] ISSN:1433-4909
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Permafrost on the Qinghai-Tibet Plateau is one of the most sensitive regions to climate warming, thus characterizing its microbial diversity and community composition may be important for understanding their potential responses to climate changes. Here, we investigated the prokaryotic diversity in a 10-m-long permafrost core from the Qinghai-Tibet Plateau by restriction fragment length polymorphism analysis targeting the 16S rRNA gene. We detected 191 and 17 bacterial and archaeal phylotypes representing 14 and 2 distinct phyla, respectively. Proteobacteria was the dominant bacterial phylum, while archaeal communities were characterized by a preponderance of Thaumarchaeota. Some of prokaryotic phylotypes were closely related to characterized species involved in carbon and nitrogen cycles, including nitrogen fixation, methane oxidation and nitrification. However, the majority of the phylotypes were only distantly related to known taxa at order or species level, suggesting the potential of novel diversity. Additionally, both bacterial α diversity and community composition changed significantly with sampling depth, where these communities mainly distributed according to core horizons. Arthrobacter-related phylotypes presented at high relative abundance in two active layer soils, while the deeper permafrost soils were dominated by Psychrobacter-related clones. Changes in bacterial community composition were correlated with most measured soil variables, such as carbon and nitrogen contents, pH, and conductivity.
[Mh] Termos MeSH primário: Microbiota
Pergelissolo/microbiologia
[Mh] Termos MeSH secundário: Archaea/genética
Archaea/isolamento & purificação
Archaea/metabolismo
Carbono/análise
Carbono/metabolismo
Nitrogênio/análise
Nitrogênio/metabolismo
Pergelissolo/química
Psychrobacter/genética
Psychrobacter/isolamento & purificação
Psychrobacter/metabolismo
RNA Ribossômico 16S/genética
Tibet
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Ribosomal, 16S); 7440-44-0 (Carbon); N762921K75 (Nitrogen)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:IM; S
[Da] Data de entrada para processamento:160402
[St] Status:MEDLINE
[do] DOI:10.1007/s00792-016-0825-y


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[PMID]:26879123
[Au] Autor:Moghadam MS; Albersmeier A; Winkler A; Cimmino L; Rise K; Hohmann-Marriott MF; Kalinowski J; Rückert C; Wentzel A; Lale R
[Ad] Endereço:Department of Biotechnology, PhotoSynLab, Faculty of Natural Sciences and Technology, NTNU Norwegian University of Science and Technology, N-7491, Trondheim, Norway. morteza.s.moghadam@ntnu.no.
[Ti] Título:Isolation and genome sequencing of four Arctic marine Psychrobacter strains exhibiting multicopper oxidase activity.
[So] Source:BMC Genomics;17:117, 2016 Feb 16.
[Is] ISSN:1471-2164
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Marine cold-temperature environments are an invaluable source of psychrophilic microbial life for new biodiscoveries. An Arctic marine bacterial strain collection was established consisting of 1448 individual isolates originating from biota, water and sediment samples taken at a various depth in the Barents Sea, North of mainland Norway, with an all year round seawater temperature of 4 °C. The entire collection was subjected to high-throughput screening for detection of extracellular laccase activity with guaiacol as a substrate. RESULTS: In total, 13 laccase-positive isolates were identified, all belonging to the Psychrobacter genus. From the most diverse four strains, based on 16S rRNA gene sequence analysis, all originating from the same Botryllus sp. colonial ascidian tunicate sample, genomic DNA was isolated and genome sequenced using a combined approach of whole genome shotgun and 8 kb mate-pair library sequencing on an Illumina MiSeq platform. The genomes were assembled and revealed genome sizes between 3.29 and 3.52 Mbp with an average G + C content of around 42%, with one to seven plasmids present in the four strains. Bioinformatics based genome mining was performed to describe the metabolic potential of these four strains and to identify gene candidates potentially responsible for the observed laccase-positive phenotype. Up to two different laccase-like multicopper oxidase (LMCO) encoding gene candidates were identified in each of the four strains. Heterologous expression of P11F6-LMCO and P11G5-LMCO2 in Escherichia coli BL21 (DE3) resulted in recombinant proteins exhibiting 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and guaiacol oxidizing activity. CONCLUSIONS: Thirteen Psychrobacter species with laccase-positive phenotype were isolated from a collection of Arctic marine bacteria. Four of the isolates were genome sequenced. The overall genome features were similar to other publicly available Psychrobacter genome sequences except for P11G5 harboring seven plasmids. However, there were differences at the pathway level as genes associated with degradation of phenolic compounds, nicotine, phenylalanine, styrene, ethylbenzene, and ethanolamine were detected only in the Psychrobacter strains reported in this study while they were absent among the other publicly available Psychrobacter genomes. In addition, six gene candidates were identified by genome mining and shown to possess T1, T2 and T3 copper binding sites as the main signature of the three-domain laccases. P11F6-LMCO and P11G5-LMCO2 were recombinantly expressed and shown to be active when ABTS and guaiacol were used as substrates.
[Mh] Termos MeSH primário: Genoma Bacteriano
Oxirredutases/metabolismo
Filogenia
Psychrobacter/classificação
[Mh] Termos MeSH secundário: Regiões Árticas
Técnicas de Tipagem Bacteriana
Composição de Bases
Sequência de Bases
Temperatura Baixa
DNA Bacteriano/genética
Dados de Sequência Molecular
Noruega
Psychrobacter/enzimologia
Psychrobacter/genética
Psychrobacter/isolamento & purificação
RNA Ribossômico 16S/genética
Água do Mar/microbiologia
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 (RNA, Ribosomal, 16S); EC 1.- (Oxidoreductases)
[Em] Mês de entrada:1610
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160217
[St] Status:MEDLINE
[do] DOI:10.1186/s12864-016-2445-4



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