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Pesquisa : D08.811.682.494 [Categoria DeCS]
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[PMID]:29269293
[Au] Autor:Tajima K; Akanuma S; Matsumoto-Akanuma A; Yamanaka D; Ishibashi KI; Adachi Y; Ohno N
[Ad] Endereço:Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
[Ti] Título:Activation of macrophages by a laccase-polymerized polyphenol is dependent on phosphorylation of Rac1.
[So] Source:Biochem Biophys Res Commun;495(3):2209-2213, 2018 01 15.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Various physiologically active effects of polymerized polyphenols have been reported. In this study, we synthesized a polymerized polyphenol (mL2a-pCA) by polymerizing caffeic acid using mutant Agaricus brasiliensis laccase and analyzed its physiological activity and mechanism of action. We found that mL2a-pCA induced morphological changes and the production of cytokines and chemokines in C3H/HeN mouse-derived resident peritoneal macrophages in vitro. The mechanisms of action of polymerized polyphenols on in vitro mouse resident peritoneal cells have not been characterized in detail previously. Herein, we report that the mL2a-pCA-induced production of interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1) in C3H/HeN mouse-derived resident peritoneal cells was inhibited by treatment with the Rac1 inhibitor NSC23766 trihydrochloride. In addition, we found that mL2a-pCA activated the phosphorylation Rac1. Taken together, the results show that mL2a-pCA induced macrophage activation via Rac1 phosphorylation-dependent pathways.
[Mh] Termos MeSH primário: Lacase/química
Ativação de Macrófagos/imunologia
Macrófagos/imunologia
Macrófagos/patologia
Neuropeptídeos/imunologia
Polifenóis/administração & dosagem
Polifenóis/química
Proteínas rac1 de Ligação ao GTP/imunologia
[Mh] Termos MeSH secundário: Animais
Células Cultivadas
Relação Dose-Resposta a Droga
Ativação Enzimática
Ativação de Macrófagos/efeitos dos fármacos
Macrófagos/efeitos dos fármacos
Masculino
Camundongos
Camundongos Endogâmicos C3H
Fosforilação/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Neuropeptides); 0 (Polyphenols); 0 (Rac1 protein, mouse); EC 1.10.3.2 (Laccase); EC 3.6.5.2 (rac1 GTP-Binding Protein)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180213
[Lr] Data última revisão:
180213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171223
[St] Status:MEDLINE


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[PMID]:27770413
[Au] Autor:Stine KJ; Jefferson K; Shulga OV
[Ad] Endereço:Department of Chemistry and Biochemistry, Center for Nanoscience, University of Missouri-Saint Louis, One University Boulevard, Saint Louis, MO, 63121-4400, USA. kstine@umsl.edu.
[Ti] Título:Nanoporous Gold for Enzyme Immobilization.
[So] Source:Methods Mol Biol;1504:37-60, 2017.
[Is] ISSN:1940-6029
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Nanoporous gold (NPG) is a material of emerging interest for immobilization of biomolecules, especially enzymes. The material provides a high surface area form of gold that is suitable for physisorption or for covalent modification by self-assembled monolayers. The material can be used as a high surface area electrode and with immobilized enzymes can be used for amperometric detection schemes. NPG can be prepared in a variety of formats from alloys containing between 20 and 50 % atomic composition of gold and less noble element(s) by dealloying procedures. Materials resembling NPG can be prepared by hydrothermal and electrodeposition methods. Related high surface area gold structures have been prepared using templating approaches. Covalent enzyme immobilization can be achieved by first forming a self-assembled monolayer on NPG bearing a terminal reactive functional group followed by conjugation to the enzyme through amide linkages to lysine residues. Enzymes can also be entrapped by physisorption or immobilized by electrostatic interactions.
[Mh] Termos MeSH primário: Enzimas Imobilizadas/química
Ouro/química
Nanoporos/ultraestrutura
[Mh] Termos MeSH secundário: Acetilcolinesterase/química
Animais
Técnicas Biossensoriais
Técnicas Eletroquímicas
Eletrodos
Estabilidade Enzimática
Glucose Oxidase/química
Peroxidase do Rábano Silvestre/química
Seres Humanos
Imunoconjugados/química
Lacase/química
Complexo de Proteína do Fotossistema I/química
Porosidade
Spinacia oleracea/enzimologia
Eletricidade Estática
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Enzymes, Immobilized); 0 (Immunoconjugates); 0 (Photosystem I Protein Complex); 7440-57-5 (Gold); EC 1.1.3.4 (Glucose Oxidase); EC 1.10.3.2 (Laccase); EC 1.11.1.- (Horseradish Peroxidase); EC 3.1.1.7 (Acetylcholinesterase)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180115
[Lr] Data última revisão:
180115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161023
[St] Status:MEDLINE


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[PMID]:29174924
[Au] Autor:Liang D; Tatomer DC; Luo Z; Wu H; Yang L; Chen LL; Cherry S; Wilusz JE
[Ad] Endereço:Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
[Ti] Título:The Output of Protein-Coding Genes Shifts to Circular RNAs When the Pre-mRNA Processing Machinery Is Limiting.
[So] Source:Mol Cell;68(5):940-954.e3, 2017 Dec 07.
[Is] ISSN:1097-4164
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Many eukaryotic genes generate linear mRNAs and circular RNAs, but it is largely unknown how the ratio of linear to circular RNA is controlled or modulated. Using RNAi screening in Drosophila cells, we identify many core spliceosome and transcription termination factors that control the RNA outputs of reporter and endogenous genes. When spliceosome components were depleted or inhibited pharmacologically, the steady-state levels of circular RNAs increased while expression of their associated linear mRNAs concomitantly decreased. Upon inhibiting RNA polymerase II termination via depletion of the cleavage/polyadenylation machinery, circular RNA levels were similarly increased. This is because readthrough transcripts now extend into downstream genes and are subjected to backsplicing. In total, these results demonstrate that inhibition or slowing of canonical pre-mRNA processing events shifts the steady-state output of protein-coding genes toward circular RNAs. This is in part because nascent RNAs become directed into alternative pathways that lead to circular RNA production.
[Mh] Termos MeSH primário: Proteínas de Drosophila/genética
Drosophila melanogaster/genética
Precursores de RNA/biossíntese
Processamento de RNA
RNA Mensageiro/biossíntese
RNA/biossíntese
Spliceossomos/genética
Transcrição Genética
[Mh] Termos MeSH secundário: Animais
Linhagem Celular
Proteínas de Drosophila/biossíntese
Drosophila melanogaster/metabolismo
Lacase/biossíntese
Lacase/genética
RNA/genética
Interferência de RNA
RNA Polimerase II/metabolismo
Precursores de RNA/genética
Fatores de Processamento de RNA/genética
Fatores de Processamento de RNA/metabolismo
Estabilidade de RNA
RNA Mensageiro/genética
Ribonucleoproteínas Nucleolares Pequenas/genética
Ribonucleoproteínas Nucleolares Pequenas/metabolismo
Spliceossomos/metabolismo
Terminação da Transcrição Genética
Transfecção
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Drosophila Proteins); 0 (RNA Precursors); 0 (RNA Splicing Factors); 0 (RNA, Messenger); 0 (RNA, circular); 0 (Ribonucleoproteins, Small Nucleolar); 0 (ribonucleoprotein, U3 small nucleolar); 63231-63-0 (RNA); EC 1.10.3.2 (Laccase); EC 2.7.7.- (RNA Polymerase II)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171226
[Lr] Data última revisão:
171226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171128
[St] Status:MEDLINE


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[PMID]:28463583
[Au] Autor:Yang SO; Sodaneath H; Lee JI; Jung H; Choi JH; Ryu HW; Cho KS
[Ad] Endereço:a Department of Environmental Science and Engineering , Ewha Womans University , Seoul , Republic of Korea.
[Ti] Título:Decolorization of acid, disperse and reactive dyes by Trametes versicolor CBR43.
[So] Source:J Environ Sci Health A Tox Hazard Subst Environ Eng;52(9):862-872, 2017 Jul 29.
[Is] ISSN:1532-4117
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The mycoremediation has been considered as a promising method for decolorizing dye wastewater. To explore new bioresource for mycoremediation, a new white-rot fungus that could decolorize various dyes commonly used in textile industries was isolated, and its ligninolytic enzyme activity and decolorization capacity were characterized. The isolated CBR43 was identified as Trametes versicolor based on the morphological properties of its fruit body and spores, as well as through partial 18S rDNA gene sequences. Isolated CBR43 displayed high activities of laccase and Mn-dependent peroxidase, whereas its lignin peroxidase activity was relatively low. These ligninolytic enzyme activities in potato dextrose broth (PDB) medium were enhanced by the addition of yeast extract (1-10 g L ). In particular, lignin peroxidase activity was increased more than 5 times in the PDB medium amended with 10 g L of yeast extract. The CBR43 decolorized more than 90% of 200 mg L acid dyes (red 114, blue 62 and black 172) and reactive dyes (red 120, blue 4, orange 16 and black 5) within 6 days in the PDB medium. CBR43 decolorized 67% of 200 mg L acid orange 7 within 9 days. The decolorization efficiencies for disperse dyes (red 1, orange 3 and black 1) were 51-80% within 9 days. The CBR43 could effectively decolorize high concentrations of acid blue 62 and acid black 172 (500-700 mg L ). The maximum dye decolorization rate was obtained at 28°C, pH 5, and 150 rpm in the PDB medium. T. versicolor CBR43 had high laccase and Mn-dependent peroxidase activities, and could decolorize a wide variety of dyes such as acid, disperse and reactive textile dyes. This fungus had decolorizing activities of azo-type dyes as well as anthraquinone-type dyes. T. versicolor CBR43 is one of promising bioresources for the decolorization of textile wastewater including various dyes.
[Mh] Termos MeSH primário: Compostos Azo/análise
Benzenossulfonatos/análise
Complexos de Coordenação/análise
Naftalenossulfonatos/análise
Trametes/crescimento & desenvolvimento
Poluentes Químicos da Água/análise
Purificação da Água/métodos
[Mh] Termos MeSH secundário: Biodegradação Ambiental
Lacase/metabolismo
Peroxidases/metabolismo
Indústria Têxtil
Trametes/enzimologia
Águas Residuais/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Azo Compounds); 0 (Benzenesulfonates); 0 (Coordination Complexes); 0 (Naphthalenesulfonates); 0 (Waste Water); 0 (Water Pollutants, Chemical); 0 (acid black 172); EC 1.10.3.2 (Laccase); EC 1.11.1.- (Peroxidases); EC 1.11.1.13 (manganese peroxidase); Q1LIY3BO0U (2-naphthol orange)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE
[do] DOI:10.1080/10934529.2017.1316164


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[PMID]:29020076
[Au] Autor:Callejón S; Sendra R; Ferrer S; Pardo I
[Ad] Endereço:ENOLAB-Estructura de Recerca Interdisciplinar BioTecMed and Departament de Microbiologia i Ecologia. Universitat de València, c/ Dr. Moliner 50, Burjassot, Spain.
[Ti] Título:Recombinant laccase from Pediococcus acidilactici CECT 5930 with ability to degrade tyramine.
[So] Source:PLoS One;12(10):e0186019, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Biogenic amines degradation by bacterial laccases is little known, so we have cloned and heterologously expressed, in E. coli, a new laccase from Pediococcus acidilactici CECT 5930 (Lpa5930), a lactic acid bacterium commonly found in foods able to degrade tyramine. The recombinant enzyme has been characterized by physical and biochemical assays. Here we report the optimization of expression and purification procedures of this laccase. DNA encoding sequence of laccase from P. acidilactici was amplified by PCR and cloned into the expression plasmid pET28a for induction by isopropyl-ß-D-thiogalactoipyranoside. Protein expression was performed in E. coli BL21(DE3) harboring pGro7 plasmid expressing a chaperone folding assistant induced by arabinose. Purification was performed by column metal-chelating chromatography on Ni-NTA-agarose. The laccase enzyme obtained has an apparent molecular mass of ∼60 kDa, an optimum temperature activity toward 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) of 28°C, and was quickly inactivated at temperatures higher than 70°C. The apparent Km value for ABTS was 1.7 mM and the Vmax obtained was 24 U/mg. In addition to ABTS, recombinant Lpa5930 laccase degraded the biogenic amine tyramine at pH 9.5 and pH 4.0 with or without ABTS as a mediator. Tyramine degradation by laccases could solve the problems generated in food due to the presence of this toxic compound.
[Mh] Termos MeSH primário: Lacase/metabolismo
Pediococcus acidilactici/enzimologia
Proteínas Recombinantes/isolamento & purificação
Tiramina/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Bactérias/química
Sequência de Bases
Benzotiazóis/metabolismo
Clonagem Molecular
Eletroforese em Gel de Poliacrilamida
Concentração de Íons de Hidrogênio
Oxirredução
Proteínas Recombinantes/metabolismo
Análise de Sequência de DNA
Espectrofotometria Ultravioleta
Especificidade por Substrato
Ácidos Sulfônicos/metabolismo
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Benzothiazoles); 0 (Recombinant Proteins); 0 (Sulfonic Acids); 28752-68-3 (2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid); EC 1.10.3.2 (Laccase); X8ZC7V0OX3 (Tyramine)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171012
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0186019


  6 / 2885 MEDLINE  
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[PMID]:28803111
[Au] Autor:Schroyen M; Van Hulle SWH; Holemans S; Vervaeren H; Raes K
[Ad] Endereço:Department of Industrial Biological Sciences, Faculty of Bioscience Engineering, Ghent University, Campus Kortrijk, Graaf Karel de Goedelaan 5, 8500 Kortrijk, Belgium.
[Ti] Título:Laccase enzyme detoxifies hydrolysates and improves biogas production from hemp straw and miscanthus.
[So] Source:Bioresour Technol;244(Pt 1):597-604, 2017 Nov.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The impact of various phenolic compounds, vanillic acid, ferulic acid, p-coumaric acid and 4-hydroxybenzoic acid on anaerobic digestion of lignocellulosic biomass (hemp straw and miscanthus) was studied. Such phenolic compounds have been known to inhibit biogas production during anaerobic digestion. The different phenolic compounds were added in various concentrations: 0, 100, 500, 1000 and 2000mg/L. A difference in inhibition of biomethane production between the phenolic compounds was noted. Hydrolysis rate, during anaerobic digestion of miscanthus was inhibited up to 50% by vanillic acid, while vanillic acid had no influence on the initial rate of biogas production during the anaerobic digestion of hemp straw. Miscanthus has a higher lignin concentration (12-30g/100gDM) making it less accessible for degradation, and in combination with phenolic compounds released after harsh pretreatments, it can cause severe inhibition levels during the anaerobic digestion, lowering biogas production. To counter the inhibition, lignin degrading enzymes can be used to remove or degrade the inhibitory phenolic compounds. The interaction of laccase and versatile peroxidase individually with the different phenolic compounds was studied to have insight in the polymerization of inhibitory compounds or breakdown of lignocellulose. Hemp straw and miscanthus were incubated with 0, 100 and 500mg/L of the different phenolic compounds for 0, 6 and 24h and pretreated with the lignin degrading enzymes. A laccase pretreatment successfully detoxified the substrate, while versatile peroxidase however was inhibited by 100mg/L of each of the individual phenolic compounds. Finally a combination of enzymatic detoxification and subsequent biogas production showed that a decrease in phenolic compounds by laccase treatment can considerably lower the inhibition levels of the biogas production.
[Mh] Termos MeSH primário: Biocombustíveis
Cannabis/química
Lacase
[Mh] Termos MeSH secundário: Ácidos Cumáricos
Lignina
Parabenos
Propionatos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biofuels); 0 (Coumaric Acids); 0 (Parabens); 0 (Propionates); 9005-53-2 (Lignin); EC 1.10.3.2 (Laccase); IBS9D1EU3J (trans-3-(4'-hydroxyphenyl)-2-propenoic acid)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170814
[St] Status:MEDLINE


  7 / 2885 MEDLINE  
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[PMID]:28780270
[Au] Autor:Naresh Kumar M; Ravikumar R; Thenmozhi S; Kirupa Sankar M
[Ad] Endereço:Bioenergy Research Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Erode 638401, TN, India.
[Ti] Título:Development of natural cellulase inhibitor mediated intensified biological pretreatment technology using Pleurotus florida for maximum recovery of cellulose from paddy straw under solid state condition.
[So] Source:Bioresour Technol;244(Pt 1):353-361, 2017 Nov.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Inhibitor mediated intensified bio-pretreatment (IMBP) technology using natural cellulase inhibitor (NCI) for maximum cellulose recovery from paddy straw was studied. Pretreatment was carried out under solid state condition. Supplementation of 8% NCI in pretreatment medium improves cellulose recovery and delignification by 1.2 and 1.5-fold respectively, compared to conventional bio-pretreatment due to inhibition of 61% of cellulase activity in IMBP. Further increase in NCI concentration showed negative effect on Pleurotus florida growth and suppress the laccase productivity by 1.1-fold. Laccase activity in IMBP was found to be 2.0U/mL on 19 day, which is higher than (1.5U/mL) conventional bio-pretreatment. Physico-chemical modifications in paddy straw before and after pretreatment were analysed by SEM, ATR-FTIR, XRD and TGA. According to these findings, the IMBP technology can be a viable eco-friendly technology for sustainable production of bioethanol with maximum cellulose recovery.
[Mh] Termos MeSH primário: Celulase
Celulose
Pleurotus
[Mh] Termos MeSH secundário: Lacase
Lignina
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9004-34-6 (Cellulose); 9005-53-2 (Lignin); EC 1.10.3.2 (Laccase); EC 3.2.1.4 (Cellulase)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171106
[Lr] Data última revisão:
171106
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170807
[St] Status:MEDLINE


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[PMID]:28763958
[Au] Autor:de Oliveira Neto JR; Rezende SG; Lobón GS; Garcia TA; Macedo IYL; Garcia LF; Alves VF; Torres IMS; Santiago MF; Schmidt F; de Souza Gil E
[Ad] Endereço:Faculdade de Farmácia, Universidade Federal de Goiás, Goiânia, Brazil.
[Ti] Título:Electroanalysis and laccase-based biosensor on the determination of phenolic content and antioxidant power of honey samples.
[So] Source:Food Chem;237:1118-1123, 2017 Dec 15.
[Is] ISSN:0308-8146
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Honey is a functional food widely consumed. Thus, the evaluation of honey samples to determine its phenolic content and antioxidant capacity (AOC) is relevant to determine its quality. Usually AOC is performed by spectrophotometric methods, which lacks reproducibility and practicality. In this context, the electroanalytical methods offer higher simplicity and accuracy. Hence, the aim of this work was to use of electroanalytical tools and laccase based biosensor on the evaluation of AOC and total phenol content (TPC) of honey samples from different countries. The antioxidant power established by electrochemical index presented good correlation with the spectrophotometric FRAP (Ferric Reducing Ability of Plasma) and DPPH (2,2-Diphenyl-1-Picrylhydrazyl) radical scavenging assays. Also, TPC results obtained by the biosensor agreed with the Folin-Ciocalteu (FC) assay. In addition to the semi quantitative results, the electroanalysis offered qualitative parameters, which were useful to indicate the nature of major phenolic compounds.
[Mh] Termos MeSH primário: Técnicas Biossensoriais
Mel/análise
[Mh] Termos MeSH secundário: Antioxidantes
Lacase
Fenóis
Reprodutibilidade dos Testes
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antioxidants); 0 (Phenols); EC 1.10.3.2 (Laccase)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171101
[Lr] Data última revisão:
171101
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170803
[St] Status:MEDLINE


  9 / 2885 MEDLINE  
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[PMID]:28726849
[Au] Autor:Lewis DM; Blatchley MR; Park KM; Gerecht S
[Ad] Endereço:Department of Chemical and Biomolecular Engineering, Johns Hopkins Physical Sciences-Oncology Center and Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland, USA.
[Ti] Título:O -controllable hydrogels for studying cellular responses to hypoxic gradients in three dimensions in vitro and in vivo.
[So] Source:Nat Protoc;12(8):1620-1638, 2017 Aug.
[Is] ISSN:1750-2799
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Oxygen (O ) acts as a potent upstream regulator of cell function. In both physiological and pathophysiological microenvironments, the O concentration is not uniformly distributed but instead follows a gradient that depends on distance from oxygen-carrying blood vessels. Such gradients have a particularly important role in development, tissue regeneration, and tumor growth. In this protocol, we describe how to use our previously reported gelatin-based O -controllable hydrogels that can provide hypoxic microenvironments in vitro. The hydrogel polymeric network is formed via a laccase-mediated cross-linking reaction. In this reaction, laccase catalyzes diferulic acid (diFA) formation to form hydrogels with an O -consuming reaction. Cells, such as cancer or endothelial cells, as well as tumor/tissue grafts, can be encapsulated in the hydrogels during hydrogel formation and then analyzed for cellular responses to 3D hypoxic gradients and to elucidate the underlying mechanisms governing these responses. Importantly, oxygen gradients can be precisely controlled in standard cell/tissue culture conditions and in vivo. This platform has been applied to study vascular morphogenesis in response to hypoxia and to understand how oxygen gradients mediate cancer cell behavior. Herein, we describe the means to validate the assay from polymer synthesis and characterization-which take 1-2 weeks and include verification of ferulic acid (FA) conjugation, rheological measurements, and O monitoring-to the study of cellular responses and use in rodent models. Time courses for biological experiments using this hydrogel are variable, and thus they may range from hours to weeks, depending on the application and user end goal.
[Mh] Termos MeSH primário: Técnicas de Cultura de Células/métodos
Técnicas Citológicas/métodos
Hidrogéis
Hipóxia/metabolismo
Oxigênio/metabolismo
Estresse Fisiológico
[Mh] Termos MeSH secundário: Animais
Células Cultivadas
Ácidos Cumáricos/metabolismo
Gelatina
Lacase/metabolismo
Camundongos Endogâmicos C57BL
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Coumaric Acids); 0 (Hydrogels); 0 (diferulic acid); 9000-70-8 (Gelatin); EC 1.10.3.2 (Laccase); S88TT14065 (Oxygen)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170731
[Lr] Data última revisão:
170731
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170721
[St] Status:MEDLINE
[do] DOI:10.1038/nprot.2017.059


  10 / 2885 MEDLINE  
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[PMID]:28651974
[Au] Autor:Behrens CJ; Linke D; Allister AB; Zelena K; Berger RG
[Ad] Endereço:Gottfried Wilhelm Leibniz Universität Hannover, Institut für Lebensmittelchemie, Callinstraße 5, 30167 Hannover, Germany. Electronic address: Christoph.Behrens@lci.uni-hannover.de.
[Ti] Título:Variants of PpuLcc, a multi-dye decolorizing laccase from Pleurotus pulmonarius expressed in Pichia pastoris.
[So] Source:Protein Expr Purif;137:34-42, 2017 Sep.
[Is] ISSN:1096-0279
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A laccase of the basidiomycete Pleurotus pulmonarius (PpuLcc) possessed strong decolorizing abilities towards artificial and natural dyes. The PpuLcc was purified from the culture supernatant via FPLC, and the corresponding gene cloned and expressed in Pichia pastoris GS115. To examine the impact of the C-terminal tail region and the signal peptide on the recombinant expression of PpuLcc, a non-modified version or different truncations (-2, -5, -13 AA) of the target protein were combined with different secretion signals. Heterologous expression of codon optimized constructs resulted in extracellular activities of the PpuLcc variants of up to 7000 U L (substrate ABTS) which was six times higher than non-codon optimized constructs. In contrast to previous works, altering the C-terminal end of the protein did not influence kinetic parameters or the rate of expression. The His-Tag purified enzymes showed high temperature optima (50-70 °C) and thermo stability. All of the recombinant variants degraded triarylmethane and azo dyes. Rapid bleaching of ß-carotene (E 160a) and the polyene acid norbixin (E 160b) using a laccase was found for the first time. Thus, the enzyme may be useful in decolorizing unwanted polyene pigments, for example from the processing of cheese, bakery, desserts, ice cream or coloured casings.
[Mh] Termos MeSH primário: Corantes/química
Proteínas Fúngicas
Lacase
Pichia/metabolismo
Pleurotus/genética
[Mh] Termos MeSH secundário: Carotenoides/química
Proteínas Fúngicas/biossíntese
Proteínas Fúngicas/química
Proteínas Fúngicas/genética
Proteínas Fúngicas/isolamento & purificação
Lacase/biossíntese
Lacase/química
Lacase/genética
Lacase/isolamento & purificação
Pichia/química
Pichia/genética
Pleurotus/enzimologia
Proteínas Recombinantes/biossíntese
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/isolamento & purificação
beta Caroteno/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Coloring Agents); 0 (Fungal Proteins); 0 (Recombinant Proteins); 01YAE03M7J (beta Carotene); 36-88-4 (Carotenoids); E8M59E17AI (norbixin); EC 1.10.3.2 (Laccase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170807
[Lr] Data última revisão:
170807
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170628
[St] Status:MEDLINE



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