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Pesquisa : B03.300.390.400.810.768.125 [Categoria DeCS]
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[PMID]:27836763
[Au] Autor:Angelakis E
[Ad] Endereço:Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes: URMITE CNRS-IRD 198 UMR 6236, Aix Marseille Université, Faculté de Médecine, 27 Bd Jean Moulin, 13385, Marseille, France.
[Ti] Título:Weight gain by gut microbiota manipulation in productive animals.
[So] Source:Microb Pathog;106:162-170, 2017 May.
[Is] ISSN:1096-1208
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Antibiotics, prebiotics and probiotics are widely used as growth promoters in agriculture. In the 1940s, use of Streptomyces aureofaciens probiotics resulted in weight gain in animals, which led to the discovery of chlortetracycline. Tetracyclines, macrolides, avoparcin and penicillins have been commonly used in livestock agriculture to promote growth through increased food intake, weight gain, and improved herd health. Prebiotic supplements including oligosaccharides, fructooligosaccharides, and galactosyl-lactose improve the growth performance of animals. Probiotics used in animal feed are mainly bacterial strains of Gram-positive bacteria and have been effectively used for weight gain in chickens, pigs, ruminants and in aquaculture. Antibiotics, prebiotics and probiotics all modify the gut microbiota and the effect of a probiotic species on the digestive flora is probably determined by bacteriocin production. Regulations governing the introduction of novel probiotics and prebiotics vary by geographical region and bias is very common in industry-funded studies. Probiotic and prebiotic foods have been consumed for centuries, either as natural components of food, or as fermented foods and it is possible to cause the same weight gain effects in humans as in animals. This review presents the use of growth promoters in food-producing animals to influence food intake and weight gain.
[Mh] Termos MeSH primário: Antibacterianos
Microbioma Gastrointestinal
Prebióticos
Probióticos
Ganho de Peso
[Mh] Termos MeSH secundário: Ração Animal/microbiologia
Animais
Antibacterianos/uso terapêutico
Aquicultura
Galinhas/crescimento & desenvolvimento
Ingestão de Alimentos
Fermentação
Microbiologia de Alimentos
Glicopeptídeos/uso terapêutico
Bactérias Gram-Positivas
Substâncias de Crescimento
História do Século XX
História do Século XXI
Seres Humanos
Lactobacillus
Macrolídeos/uso terapêutico
Obesidade
Oligossacarídeos/metabolismo
Penicilinas/uso terapêutico
Aves Domésticas/crescimento & desenvolvimento
Probióticos/história
Probióticos/uso terapêutico
Ruminantes/crescimento & desenvolvimento
Streptomyces aureofaciens
Suínos/crescimento & desenvolvimento
Tetraciclinas/uso terapêutico
[Pt] Tipo de publicação:HISTORICAL ARTICLE; JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Glycopeptides); 0 (Growth Substances); 0 (Macrolides); 0 (Oligosaccharides); 0 (Penicillins); 0 (Prebiotics); 0 (Tetracyclines); 0 (fructooligosaccharide); WJ13O9MNTI (avoparcin)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171108
[Lr] Data última revisão:
171108
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161113
[St] Status:MEDLINE


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[PMID]:27449215
[Au] Autor:Farkasovská J; Godány A
[Ad] Endereço:Institute of Molecular Biology, Laboratory of Prokaryotic Biology, Slovak Academy of Sciences, Bratislava, Slovakia. jarmila.farkasovska@savba.sk.
[Ti] Título:Characterization of the N-Terminal Catalytic Domain of Lytµ1/6, an Endolysin from Streptomyces aureofaciens Phage µ1/6.
[So] Source:Curr Microbiol;73(4):602-10, 2016 Oct.
[Is] ISSN:1432-0991
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Previous characterization of Lytµ1/6, an endolysin from Streptomyces aureofaciens phage µ1/6, suggested that the N-terminal domain is responsible for the catalytic activity of Lytµ1/6. Mutational analyses (deletions and site-directed mutagenesis) demonstrated that lytic activity of Lytµ1/6 relies on the N-terminal part of about 200 amino acid residues. Various C-terminally truncated versions of Lytµ1/6 failed to cause lysis, indicating the necessity of the CBD for full enzyme activity. Functional analysis of the point mutants suggested that the residues K27, H31, E109, H176, and D184 were essential for lytic activity of the µ1/6 endolysin. Further characterization of the purified Lytµ1/6 revealed that this endolysin is an N-acetylmuramoyl-L-alanine amidase which seems to be unrelated to any of the known conserved catalytic domains of phage endolysins or bacterial autolysins.
[Mh] Termos MeSH primário: Bacteriófagos/enzimologia
Endopeptidases/química
Endopeptidases/metabolismo
Streptomyces aureofaciens/virologia
Proteínas Virais/química
Proteínas Virais/metabolismo
[Mh] Termos MeSH secundário: Motivos de Aminoácidos
Sequência de Aminoácidos
Bacteriófagos/química
Bacteriófagos/genética
Domínio Catalítico
Endopeptidases/genética
Dados de Sequência Molecular
Mutação Puntual
Alinhamento de Sequência
Proteínas Virais/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Viral Proteins); EC 3.4.- (Endopeptidases); EC 3.4.99.- (endolysin)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160725
[St] Status:MEDLINE
[do] DOI:10.1007/s00284-016-1100-2


  3 / 290 MEDLINE  
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[PMID]:26976746
[Au] Autor:Eng CH; Yuzawa S; Wang G; Baidoo EE; Katz L; Keasling JD
[Ad] Endereço:Synthetic Biology Engineering Research Center , 5885 Hollis Street, Emeryville, California 94608, United States.
[Ti] Título:Alteration of Polyketide Stereochemistry from anti to syn by a Ketoreductase Domain Exchange in a Type I Modular Polyketide Synthase Subunit.
[So] Source:Biochemistry;55(12):1677-80, 2016 Mar 29.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Polyketide natural products have broad applications in medicine. Exploiting the modular nature of polyketide synthases to alter stereospecificity is an attractive strategy for obtaining natural product analogues with altered pharmaceutical properties. We demonstrate that by retaining a dimerization element present in LipPks1+TE, we are able to use a ketoreductase domain exchange to alter α-methyl group stereochemistry with unprecedented retention of activity and simultaneously achieve a novel alteration of polyketide product stereochemistry from anti to syn. The substrate promiscuity of LipPks1+TE further provided a unique opportunity to investigate the substrate dependence of ketoreductase activity in a polyketide synthase module context.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Policetídeo Sintases/química
Subunidades Proteicas/química
[Mh] Termos MeSH secundário: Proteínas de Bactérias/metabolismo
Policetídeo Sintases/metabolismo
Estrutura Terciária de Proteína/fisiologia
Subunidades Proteicas/metabolismo
Estereoisomerismo
Streptomyces aureofaciens/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Protein Subunits); 79956-01-7 (Polyketide Synthases)
[Em] Mês de entrada:1608
[Cu] Atualização por classe:160329
[Lr] Data última revisão:
160329
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160316
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.6b00129


  4 / 290 MEDLINE  
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[PMID]:26685675
[Au] Autor:Bekeova C; Rehakova A; Feckova L; Vlckova S; Novakova R; Mingyar E; Kormanec J
[Ad] Endereço:Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, 845 51, Bratislava, Slovak Republic.
[Ti] Título:Characterisation of the genes involved in the biosynthesis and attachment of the aminodeoxysugar D-forosamine in the auricin gene cluster of Streptomyces aureofaciens CCM3239.
[So] Source:Appl Microbiol Biotechnol;100(7):3177-95, 2016 Apr.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:We previously identified the aur1 gene cluster which produces the angucycline antibiotic auricin. Preliminary characterisation of auricin revealed that it is modified by a single aminodeoxysugar, D-forosamine. Here we characterise the D-forosamine-specific genes. The four close tandem genes, aur1TQSV, encoding enzymes involved in the initial steps of the deoxysugar biosynthesis, were located on a large operon with other core auricin biosynthetic genes. Deleting these genes resulted in the absence of auricin and the production of deglycosylated auricin intermediates. The two final D-forosamine biosynthetic genes, sa59, an NDP-hexose aminotransferase, and sa52, an NDP-aminohexose N-dimethyltransferase, are located in a region rather distant from the core auricin genes. A deletion analysis of these genes confirmed their role in D-forosamine biosynthesis. The Δsa59 mutant had a phenotype similar to that of the cluster deletion mutant, while the Δsa52 mutant produced an auricin with a demethylated D-forosamine. Although auricin contains a single deoxyhexose, two glycosyltransferase genes were found to participate in the attachment of D-forosamine to the auricin aglycon. An analysis of the expression of the D-forosamine biosynthesis genes revealed that the initial D-forosamine biosynthetic genes aur1TQSV are regulated together with the other auricin core genes by the aur1Ap promoter under the control of the auricin-specific activator Aur1P. The expression of the other D-forosamine genes, however, is governed by promoters differentially dependent upon the two SARP family auricin-specific activators Aur1PR3 and Aur1PR4. These promoters contain direct repeats similar to the SARP consensus sequence and are involved in the interaction with both regulators.
[Mh] Termos MeSH primário: Antibacterianos/biossíntese
Regulação Bacteriana da Expressão Gênica
Hexosaminas/biossíntese
Macrolídeos/metabolismo
Streptomyces aureofaciens/genética
Transaminases/genética
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Sequência de Bases
Deleção de Genes
Família Multigênica
Óperon
Regiões Promotoras Genéticas
Metabolismo Secundário/genética
Alinhamento de Sequência
Streptomyces aureofaciens/metabolismo
Transaminases/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Proteins); 0 (Hexosamines); 0 (Macrolides); 0 (auricin); 18423-27-3 (forosamine); EC 2.6.1.- (Transaminases)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151222
[St] Status:MEDLINE
[do] DOI:10.1007/s00253-015-7214-9


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[PMID]:26710788
[Au] Autor:Mitkevich VA; Pace CN; Koschinski A; Makarov AA; Ilinskaya ON
[Ad] Endereço:Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991 Russia;
[Ti] Título:[Cytotoxicity mechanism of the RNase Sa cationic mutants involves inhibition of potassium current through Ca2+-activated channels].
[So] Source:Mol Biol (Mosk);49(6):1041-7, 2015 Nov-Dec.
[Is] ISSN:0026-8984
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:Bacterial ribonucleases (RNases) are considered to be potential anticancer agents. One of most important determinants of RNase cytotoxicity is the net charge of the molecule. In this work a set of mutants of the RNase from Streptomyces aureofaciens (RNase Sa), differing in the net charge of the protein molecules (from -7 to +6) and localization of additional positive charge at the N- or C-terminus of the molecule is used to study inhibition of cell growth. It has been found that the mutants of RNase with increased cationicity most effectively inhibit the growth of HEKhSK4 cells. Additional positive charge at the C-terminus of the molecule also increases the cytotoxic properties of RNases. It has been shown that RNase cytotoxicity correlated with the level of inhibition of the K+-current in cells.
[Mh] Termos MeSH primário: Mutação
Potássio/metabolismo
Ribonucleases/toxicidade
Canais de Potássio Ativados por Cálcio de Condutância Baixa/metabolismo
[Mh] Termos MeSH secundário: Sobrevivência Celular/efeitos dos fármacos
Células HEK293
Seres Humanos
Transporte de Íons
Estrutura Terciária de Proteína
Ribonucleases/química
Ribonucleases/genética
Eletricidade Estática
Streptomyces aureofaciens/enzimologia
[Pt] Tipo de publicação:ENGLISH ABSTRACT; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Small-Conductance Calcium-Activated Potassium Channels); EC 3.1.- (Ribonucleases); RWP5GA015D (Potassium)
[Em] Mês de entrada:1602
[Cu] Atualização por classe:151229
[Lr] Data última revisão:
151229
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151230
[St] Status:MEDLINE
[do] DOI:10.7868/S0026898415060191


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[PMID]:26323354
[Au] Autor:Jiang W; Zhao X; Gabrieli T; Lou C; Ebenstein Y; Zhu TF
[Ad] Endereço:School of Life Sciences, Center for Synthetic and Systems Biology, MOE Key Laboratory of Bioinformatics, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Tsinghua University, Beijing 100084, China.
[Ti] Título:Cas9-Assisted Targeting of CHromosome segments CATCH enables one-step targeted cloning of large gene clusters.
[So] Source:Nat Commun;6:8101, 2015 Sep 01.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The cloning of long DNA segments, especially those containing large gene clusters, is of particular importance to synthetic and chemical biology efforts for engineering organisms. While cloning has been a defining tool in molecular biology, the cloning of long genome segments has been challenging. Here we describe a technique that allows the targeted cloning of near-arbitrary, long bacterial genomic sequences of up to 100 kb to be accomplished in a single step. The target genome segment is excised from bacterial chromosomes in vitro by the RNA-guided Cas9 nuclease at two designated loci, and ligated to the cloning vector by Gibson assembly. This technique can be an effective molecular tool for the targeted cloning of large gene clusters that are often expensive to synthesize by gene synthesis or difficult to obtain directly by traditional PCR and restriction-enzyme-based methods.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Cromossomos Bacterianos/genética
Clonagem Molecular/métodos
DNA Bacteriano/genética
Endonucleases/metabolismo
Família Multigênica/genética
[Mh] Termos MeSH secundário: Bacillus subtilis/genética
RNA Polimerases Dirigidas por DNA/metabolismo
Escherichia coli/genética
Vetores Genéticos
Genoma Bacteriano/genética
Streptomyces/genética
Streptomyces aureofaciens/genética
Proteínas Virais/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (DNA, Bacterial); 0 (Viral Proteins); EC 2.7.7.- (bacteriophage T7 RNA polymerase); EC 2.7.7.6 (DNA-Directed RNA Polymerases); EC 3.1.- (Cas9 endonuclease Streptococcus pyogenes); EC 3.1.- (Endonucleases)
[Em] Mês de entrada:1604
[Cu] Atualização por classe:170922
[Lr] Data última revisão:
170922
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150902
[St] Status:MEDLINE
[do] DOI:10.1038/ncomms9101


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[PMID]:26033926
[Au] Autor:Yamada R; Higo T; Yoshikawa C; China H; Yasuda M; Ogino H
[Ad] Endereço:Dept. of Chemical Engineering, Osaka Prefecture University, Sakai, Osaka, 599-8531,, Japan.
[Ti] Título:Random mutagenesis and selection of organic solvent-stable haloperoxidase from Streptomyces aureofaciens.
[So] Source:Biotechnol Prog;31(4):917-24, 2015 Jul-Aug.
[Is] ISSN:1520-6033
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Haloperoxidases are useful oxygenases involved in halogenation of a range of water-insoluble organic compounds and can be used without additional high-cost cofactors. In particular, organic solvent-stable haloperoxidases are desirable for enzymatic halogenations in the presence of organic solvents. In this study, we adopted a directed evolution approach by error-prone polymerase chain reaction to improve the organic solvent-stability of the homodimeric BPO-A1 haloperoxidase from Streptomyces aureofaciens. Among 1,000 mutant BPO-A1 haloperoxidases, an organic solvent-stable mutant OST48 with P123L and P241A mutations and a high active mutant OST959 with H53Y and G162R mutations were selected. The residual activity of mutant OST48 after incubation in 40% (v/v) 1-propanol for 1 h was 1.8-fold higher than that of wild-type BPO-A1. In addition, the OST48 mutant showed higher stability in methanol, ethanol, dimethyl sulfoxide, and N,N-dimethylformamide than wild-type BPO-A1 haloperoxidase. Moreover, after incubation at 80°C for 1 h, the residual activity of mutant OST959 was 4.6-fold higher than that of wild-type BPO-A1. Based on the evaluation of single amino acid-substituted mutant models, stabilization of the hydrophobic core derived from P123L mutation and increased numbers of hydrogen bonds derived from G162R mutation led to higher organic solvent-stability and thermostability, respectively.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Peroxidases/química
Peroxidases/genética
Streptomyces aureofaciens/enzimologia
Streptomyces aureofaciens/genética
[Mh] Termos MeSH secundário: Proteínas de Bactérias/metabolismo
Estabilidade Enzimática
Evolução Molecular
Mutagênese
Peroxidases/metabolismo
Solventes
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Solvents); EC 1.11.1.- (Peroxidases)
[Em] Mês de entrada:1605
[Cu] Atualização por classe:150811
[Lr] Data última revisão:
150811
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150603
[St] Status:MEDLINE
[do] DOI:10.1002/btpr.2117


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[PMID]:25801098
[Au] Autor:Knirschova R; Novakova R; Mingyar E; Bekeova C; Homerova D; Kormanec J
[Ad] Endereço:Institute of Molecular Biology, Slovak Academy of Sciences, 845 51 Bratislava, Slovak Republic.
[Ti] Título:Utilization of a reporter system based on the blue pigment indigoidine biosynthetic gene bpsA for detection of promoter activity and deletion of genes in Streptomyces.
[So] Source:J Microbiol Methods;113:1-3, 2015 Jun.
[Is] ISSN:1872-8359
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The integrative promoter-probe plasmid pBPSA1 was constructed using a promoterless Streptomyces aureofaciens CCM3239 bpsA gene encoding a non-ribosomal peptide synthase for the biosynthesis of a blue pigment, indigoidine. bpsA was also used to prepare pAMR4 plasmid for the deletion of genes in Streptomyces with facile identification of double crossover recombination.
[Mh] Termos MeSH primário: Genes Bacterianos
Genes Reporter
Piperidonas/metabolismo
Regiões Promotoras Genéticas
Deleção de Sequência
Streptomyces aureofaciens/genética
[Mh] Termos MeSH secundário: Peptídeo Sintases/genética
Plasmídeos
Recombinação Genética
Streptomyces aureofaciens/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Piperidones); 2435-59-8 (indigoidine); EC 6.3.2.- (Peptide Synthases); EC 6.3.2.- (non-ribosomal peptide synthase)
[Em] Mês de entrada:1602
[Cu] Atualização por classe:150513
[Lr] Data última revisão:
150513
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150325
[St] Status:MEDLINE


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[PMID]:25658510
[Au] Autor:Eshelli M; Harvey L; Edrada-Ebel R; McNeil B
[Ad] Endereço:Food Science and Technology Department, Faculty of Agriculture, University of Tripoli, Tripoli, Libya. m.eshelli@hotmail.com.
[Ti] Título:Metabolomics of the bio-degradation process of aflatoxin B1 by actinomycetes at an initial pH of 6.0.
[So] Source:Toxins (Basel);7(2):439-56, 2015 Feb 04.
[Is] ISSN:2072-6651
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Contamination of food and feed by Aflatoxin B1 (AFB1) is a cause of serious economic and health problems. Different processes have been used to degrade AFB1. In this study, biological degradation of AFB1 was carried out using three Actinomycete species, Rhodococcus erythropolis ATCC 4277, Streptomyces lividans TK 24, and S. aureofaciens ATCC 10762, in liquid cultures. Biodegradation of AFB1 was optimised under a range of temperatures from 25 to 40 °C and pH values of 4.0 to 8.0. An initial concentration of 20 µg/mL of AFB1 was used in this study. The amount of AFB1 remaining was measured against time by thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC), coupled with UV and mass spectrometry (LC-MS). All species were able to degrade the AFB1, and no significant difference was found between them. AFB1 remained in the liquid culture for R. erythropolis, S. lividans and S. aureofaciens were 0.81 µg/mL, 2.41 µg/mL and 2.78 µg/mL respectively, at the end of the first 24 h. Degradation occurred at all incubation temperatures and the pH with the optimal conditions for R. erythropolis was achieved at 30 °C and pH 6, whereas for S. lividans and S. aureofaciens the optimum conditions for degradation were 30 °C and pH 5. Analysis of the degradative route indicated that each microorganism has a different way of degrading AFB1. The metabolites produced by R. erythropolis were significantly different from the other two microorganisms. Products of degradation were identified through metabolomic studies by utilizing high-resolution mass spectral data. Mass spectrometric analysis indicated that the degradation of AFB1 was associated with the appearance of a range of lower molecular weight compounds. The pathway of degradation or chemical alteration of AFB1 was followed by means of high resolution Fourier transform mass spectrometry (HR-FTMS) analysis as well as through the MS2 fragmentation to unravel the degradative pathway for AFB1. AFB1 bio-degradation was coupled with the accumulation of intermediates of fatty acid metabolism and glycolysis. A plausible mechanism of degradation of AFB1 by Rhodococcus was hypothesized.
[Mh] Termos MeSH primário: Aflatoxina B1/metabolismo
Contaminação de Alimentos/prevenção & controle
Metabolômica/métodos
Rhodococcus/metabolismo
Streptomyces aureofaciens/metabolismo
Streptomyces lividans/metabolismo
[Mh] Termos MeSH secundário: Biodegradação Ambiental
Temperatura Alta
Concentração de Íons de Hidrogênio
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
9N2N2Y55MH (Aflatoxin B1)
[Em] Mês de entrada:1510
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150207
[St] Status:MEDLINE
[do] DOI:10.3390/toxins7020439


  10 / 290 MEDLINE  
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[PMID]:25219533
[Au] Autor:Mingyar E; Feckova L; Novakova R; Bekeova C; Kormanec J
[Ad] Endereço:Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska Cesta 21, 845 51, Bratislava, Slovak Republic.
[Ti] Título:A γ-butyrolactone autoregulator-receptor system involved in the regulation of auricin production in Streptomyces aureofaciens CCM 3239.
[So] Source:Appl Microbiol Biotechnol;99(1):309-25, 2015 Jan.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:The γ-butyrolactone (GBL) autoregulator-receptor systems play a role in controlling secondary metabolism and/or morphological differentiation in many Streptomyces species. We previously identified the aur1 gene cluster, located on the Streptomyces aureofaciens CCM 3239 large linear plasmid pSA3239, which is responsible for the production of the angucycline antibiotic auricin. Here, we describe the characterisation of two genes, sagA and sagR, encoding GBL autoregulatory signalling homologues, which lie in the upstream part of the aur1 cluster. SagA was similar to GBL synthases and SagR to GBL receptors. The expression of each gene is directed by its own promoter, sagAp for sagA and sagRp for sagR. Both genes were active mainly during the exponential phase, and their transcription was interdependent. The disruption of sagA abolished auricin production, while the disruption of sagR resulted in precocious but dramatically reduced auricin production. Transcription from the aur1Pp and aur1Rp promoters, which direct the expression of auricin-specific cluster-situated regulators (CSRs), was also precocious and increased in the sagR mutant strain. In addition, SagR was also shown to specifically bind both promoters in vitro. These results indicated that the SagA-SagR GBL system regulates auricin production. Unlike many other GBL receptors, SagR does not bind its own promoter, but Aur1R, an auricin-specific repressor from the family of pseudo GBL receptors, does bind both sagAp and sagRp promoters. Moreover, the expression of both promoters was deregulated in an aur1R mutant, indicating that the SagA-SagR GBL system is regulated by a feedback mechanism involving the auricin-specific CSR Aur1R, which regulates downstream.
[Mh] Termos MeSH primário: Antibacterianos/metabolismo
Regulação Bacteriana da Expressão Gênica
Macrolídeos/metabolismo
Streptomyces aureofaciens/genética
Streptomyces aureofaciens/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Perfilação da Expressão Gênica
Transcrição Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Proteins); 0 (Macrolides); 0 (auricin)
[Em] Mês de entrada:1509
[Cu] Atualização por classe:150108
[Lr] Data última revisão:
150108
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140916
[St] Status:MEDLINE
[do] DOI:10.1007/s00253-014-6057-0



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