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Pesquisa : D08.811.682.180 [Categoria DeCS]
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[PMID]:28245268
[Au] Autor:Liang D; Zhu T; Ni Z; Lin L; Tang Y; Wang Z; Wang X; Wang J; Lv X; Xia H
[Ad] Endereço:Institute of Pomology and Olericulture, Sichuan Agricultural University, Chengdu, Sichuan, China.
[Ti] Título:Ascorbic acid metabolism during sweet cherry (Prunus avium) fruit development.
[So] Source:PLoS One;12(2):e0172818, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:To elucidate metabolism of ascorbic acid (AsA) in sweet cherry fruit (Prunus avium 'Hongdeng'), we quantified AsA concentration, cloned sequences involved in AsA metabolism and investigated their mRNA expression levels, and determined the activity levels of selected enzymes during fruit development and maturation. We found that AsA concentration was highest at the petal-fall period (0 days after anthesis) and decreased progressively during ripening, but with a slight increase at maturity. AsA did nevertheless continue to accumulate over time because of the increase in fruit fresh weight. Full-length cDNAs of 10 genes involved in the L-galactose pathway of AsA biosynthesis and 10 involved in recycling were obtained. Gene expression patterns of GDP-L-galactose phosphorylase (GGP2), L-galactono-1, 4-lactone dehydrogenase (GalLDH), ascorbate peroxidase (APX3), ascorbate oxidase (AO2), glutathione reductase (GR1), and dehydroascorbate reductase (DHAR1) were in accordance with the AsA concentration pattern during fruit development, indicating that genes involved in ascorbic acid biosynthesis, degradation, and recycling worked in concert to regulate ascorbic acid accumulation in sweet cherry fruit.
[Mh] Termos MeSH primário: Ácido Ascórbico/metabolismo
Frutas/metabolismo
Prunus avium/metabolismo
[Mh] Termos MeSH secundário: Ascorbato Oxidase/genética
Ascorbato Oxidase/metabolismo
Ascorbato Peroxidases/genética
Ascorbato Peroxidases/metabolismo
Metabolismo dos Carboidratos/genética
Metabolismo dos Carboidratos/fisiologia
DNA Complementar/genética
Frutas/enzimologia
Frutas/genética
Regulação da Expressão Gênica de Plantas/genética
Glutationa Redutase/genética
Glutationa Redutase/metabolismo
Monoéster Fosfórico Hidrolases/genética
Monoéster Fosfórico Hidrolases/metabolismo
Proteínas de Plantas/genética
Proteínas de Plantas/metabolismo
Prunus avium/enzimologia
Prunus avium/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Complementary); 0 (Plant Proteins); EC 1.10.3.3 (Ascorbate Oxidase); EC 1.11.1.11 (Ascorbate Peroxidases); EC 1.8.1.7 (Glutathione Reductase); EC 3.1.3.2 (Phosphoric Monoester Hydrolases); PQ6CK8PD0R (Ascorbic Acid)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170828
[Lr] Data última revisão:
170828
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170301
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0172818


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[PMID]:26725933
[Au] Autor:Lai W; Wei Q; Xu M; Zhuang J; Tang D
[Ad] Endereço:State Key Laboratory of Photocatalysis on Energy and Environment, Key Laboratory of Analysis and Detection for Food Safety (Fujian Province & MOE), Institute of Nanomedicine and Nanobiosensing, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China.
[Ti] Título:Enzyme-controlled dissolution of MnO nanoflakes with enzyme cascade amplification for colorimetric immunoassay.
[So] Source:Biosens Bioelectron;89(Pt 1):645-651, 2017 Mar 15.
[Is] ISSN:1873-4235
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A new colorimetric immunosensing platform accompanying enzyme cascade amplification strategy was fabricated for quantitative screening of small-molecular mycotoxins (aflatoxin B , AFB used in this case) coupling with enzyme-controlled dissolution of MnO nanoflakes. The visual colored assay was executed by high-efficient MnO -3,3',5,5'-tetramethylbenzidine (TMB) system (blue). In the presence of ascorbic acid, MnO nanoflakes were dissolved into Mn ions, thus resulting in a perceptible color change from blue to colorless. The reaction could be weakened through ascorbate oxidase to catalyze ascorbic acid into dehydroascorbic acid, which indirectly depended on the concentration of ascorbate oxidase. By using ascorbate oxidase/ anti-AFB antibody-labeled gold nanoparticles, a novel competitive-type colorimetric enzyme immunoassay was developed for detection of AFB on AFB -bovine serum albumin (BSA)-conjugated magnetic beads. Upon addition of target AFB , the analyte competed with the conjugated AFB -BSA on the magnetic beads for the labeled anti-AFB antibody on the gold nanoparticles. Under optimal conditions, the absorbance decreased with increasing target AFB within the dynamic range of 0.05-150ngmL with a detection limit of 6.5pgmL at the 3S level. The precision and specificity of the MnO -TMB-based immunosensing system were acceptable. In addition, method accuracy was further validated for monitoring spiked peanut samples, giving results matched well with those obtained from commercialized AFB ELISA kit.
[Mh] Termos MeSH primário: Aflatoxina B1/análise
Arachis/microbiologia
Técnicas Biossensoriais/métodos
Contaminação de Alimentos/análise
Compostos de Manganês/química
Nanoestruturas/química
Óxidos/química
[Mh] Termos MeSH secundário: Animais
Anticorpos Imobilizados/química
Arachis/química
Ascorbato Oxidase/química
Aspergillus flavus/química
Benzidinas/química
Bovinos
Colorimetria/métodos
Microbiologia de Alimentos
Ouro/química
Imunoensaio/métodos
Limite de Detecção
Nanopartículas Metálicas/química
Nanopartículas Metálicas/ultraestrutura
Nanoestruturas/ultraestrutura
Soroalbumina Bovina/química
Solubilidade
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Immobilized); 0 (Benzidines); 0 (Manganese Compounds); 0 (Oxides); 27432CM55Q (Serum Albumin, Bovine); 3B3T5CB8EO (3,3',5,5'-tetramethylbenzidine); 7440-57-5 (Gold); 9N2N2Y55MH (Aflatoxin B1); EC 1.10.3.3 (Ascorbate Oxidase); TF219GU161 (manganese dioxide)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160105
[St] Status:MEDLINE


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[PMID]:27597995
[Au] Autor:Xin S; Tao C; Li H
[Ad] Endereço:College of life sciences, Key laboratory of Agrobiotechnology, Shihezi University, Shihezi, Xinjiang, China.
[Ti] Título:Cloning and Functional Analysis of the Promoter of an Ascorbate Oxidase Gene from Gossypium hirsutum.
[So] Source:PLoS One;11(9):e0161695, 2016.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Apoplastic ascorbate oxidase (AO) plays significant roles in plant cell growth. However, the mechanism of underlying the transcriptional regulation of AO in Gossypium hirsutum remains unclear. Here, we obtained a 1,920-bp promoter sequence from the Gossypium hirsutum ascorbate oxidase (GhAO1) gene, and this GhAO1 promoter included a number of known cis-elements. Promoter activity analysis in overexpressing pGhAO1::GFP-GUS tobacco (Nicotiana benthamiana) showed that the GhAO1 promoter exhibited high activity, driving strong reporter gene expression in tobacco trichomes, leaves and roots. Promoter 5'-deletion analysis demonstrated that truncated GhAO1 promoters with serial 5'-end deletions had different GUS activities. A 360-bp fragment was sufficient to activate GUS expression. The P-1040 region had less GUS activity than the P-720 region, suggesting that the 320-bp region from nucleotide -720 to -1040 might include a cis-element acting as a silencer. Interestingly, an auxin-responsive cis-acting element (TGA-element) was uncovered in the promoter. To analyze the function of the TGA-element, tobacco leaves transformed with promoters with different 5' truncations were treated with indole-3-acetic acid (IAA). Tobacco leaves transformed with the promoter regions containing the TGA-element showed significantly increased GUS activity after IAA treatment, implying that the fragment spanning nucleotides -1760 to -1600 (which includes the TGA-element) might be a key component for IAA responsiveness. Analyses of the AO promoter region and AO expression pattern in Gossypium arboreum (Ga, diploid cotton with an AA genome), Gossypium raimondii (Gr, diploid cotton with a DD genome) and Gossypium hirsutum (Gh, tetraploid cotton with an AADD genome) indicated that AO promoter activation and AO transcription were detected together only in D genome/sub-genome (Gr and Gh) cotton. Taken together, these results suggest that the 1,920-bp GhAO1 promoter is a functional sequence with a potential effect on fiber cell development, mediated by TGA-element containing sequences, via the auxin-signaling pathway.
[Mh] Termos MeSH primário: Ascorbato Oxidase/genética
Gossypium/genética
Ácidos Indolacéticos/metabolismo
Regiões Promotoras Genéticas/genética
[Mh] Termos MeSH secundário: Ascorbato Oxidase/biossíntese
Ascorbato Oxidase/química
Ascorbato Oxidase/isolamento & purificação
Clonagem Molecular
Regulação Enzimológica da Expressão Gênica
Gossypium/enzimologia
Plantas Geneticamente Modificadas/genética
Plantas Geneticamente Modificadas/crescimento & desenvolvimento
Transdução de Sinais/genética
Tabaco/enzimologia
Tabaco/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Indoleacetic Acids); EC 1.10.3.3 (Ascorbate Oxidase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170801
[Lr] Data última revisão:
170801
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160907
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0161695


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[PMID]:27459340
[Au] Autor:Zhang X; Yu HJ; Zhang XM; Yang XY; Zhao WC; Li Q; Jiang WJ
[Ad] Endereço:Key Laboratory of Horticultural Crops Genetic Improvement (Ministry of Agriculture), Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
[Ti] Título:Effect of nitrogen deficiency on ascorbic acid biosynthesis and recycling pathway in cucumber seedlings.
[So] Source:Plant Physiol Biochem;108:222-230, 2016 Nov.
[Is] ISSN:1873-2690
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:L-Ascorbic acid (AsA, ascorbate) is one of the most abundant natural antioxidants, and it is an important factor in the nutritional quality of cucumber. In this work, key enzymes involved in the ascorbic acid biosynthesis and recycling pathway in cucumber seedlings under nitrogen deficiency were investigated at the levels of transcription and enzyme activity. The activities of myo-inositol oxygenase (MIOX) and transcript levels of MIOXs increased dramatically, while the activities of ascorbate oxidase (AO) and glutathione reductase (GR) and transcript levels of AOs and GR2 decreased significantly in N-limited leaves, as did the ascorbate concentration, in nitrogen-deficient cucumber seedlings. The activities of other enzymes and transcript levels of other genes involved in the ascorbate recycling pathway and ascorbate synthesis pathways decreased or remained unchanged under nitrogen deficiency. These results indicate that nitrogen deficiency induced genes involved in the ascorbate-glutathione recycling and myo-inositol pathway in cucumber leaves. Thus, the AO, GR and MIOX involved in the pathways might play roles in AsA accumulation.
[Mh] Termos MeSH primário: Ácido Ascórbico/metabolismo
Cucumis sativus/metabolismo
Nitrogênio/deficiência
Plântulas/metabolismo
[Mh] Termos MeSH secundário: Ascorbato Oxidase/genética
Ascorbato Oxidase/metabolismo
Ácido Ascórbico/biossíntese
Regulação da Expressão Gênica de Plantas
Glutationa Redutase/genética
Glutationa Redutase/metabolismo
Nitrogênio/metabolismo
Folhas de Planta/metabolismo
Plântulas/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
EC 1.10.3.3 (Ascorbate Oxidase); EC 1.8.1.7 (Glutathione Reductase); N762921K75 (Nitrogen); PQ6CK8PD0R (Ascorbic Acid)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170813
[Lr] Data última revisão:
170813
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160727
[St] Status:MEDLINE


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[PMID]:27236140
[Au] Autor:Bi H; Duarte CM; Brito M; Vilas-Boas V; Cardoso S; Freitas P
[Ad] Endereço:International Iberian Nanotechnology Laboratory (INL), Av. Mestre José Veiga, 4715-330 Braga, Portugal. Electronic address: hongyan.bi@inl.int.
[Ti] Título:Performance enhanced UV/vis spectroscopic microfluidic sensor for ascorbic acid quantification in human blood.
[So] Source:Biosens Bioelectron;85:568-572, 2016 Nov 15.
[Is] ISSN:1873-4235
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Quantitative analysis of antioxidants in a fast, simple and accurate manner is of great importance in the view of real-time monitoring the health of individuals. Recently, we have developed a UV/vis spectroscopic microfluidic sensor to specifically quantify ascorbic acid based on the immobilization of ascorbate oxidase, a relatively unstable enzyme. In this work, three different strategies for the immobilization of the unstable enzyme, including alumina sol-gel encapsulation, physisorption to PDMS channels with, and without alumina xerogel modification, were compared to build a microsensor. We found that the loading amount of the enzyme is not the determinative factor for the performance of the microfluidic biosensor but the retained activity of the enzyme and diffusion in the microfluidic channel. Taking into account of the two factors, the protocol of adsorbing enzymes to alumina (Al2O3) xerogel modified PDMS surface was demonstrated to be the best for preparing the microfluidic sensor among the utilized protocols. The microsensor prepared under the optimized protocol was further used to quantify ascorbic acid in human blood, where only dozens of microliters of blood (few drops) was required, demonstrating its potential application in clinical diagnosis. The developed strategy is featured with optimized enzymatic activity, simple process of microfluidic platform, low sample consumption, and straightforward spectrophotometry based detection.
[Mh] Termos MeSH primário: Ácido Ascórbico/sangue
Técnicas Biossensoriais/métodos
Técnicas Analíticas Microfluídicas/métodos
Espectrofotometria Ultravioleta/métodos
[Mh] Termos MeSH secundário: Adsorção
Óxido de Alumínio/química
Ascorbato Oxidase/química
Ascorbato Oxidase/metabolismo
Ácido Ascórbico/metabolismo
Dimetilpolisiloxanos/química
Enzimas Imobilizadas/química
Enzimas Imobilizadas/metabolismo
Seres Humanos
Limite de Detecção
Transição de Fase
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Dimethylpolysiloxanes); 0 (Enzymes, Immobilized); 63148-62-9 (baysilon); EC 1.10.3.3 (Ascorbate Oxidase); LMI26O6933 (Aluminum Oxide); PQ6CK8PD0R (Ascorbic Acid)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170809
[Lr] Data última revisão:
170809
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160529
[St] Status:MEDLINE


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[PMID]:26709272
[Au] Autor:Nah H; Yim J; Lee SG; Lim JB; Kim JH
[Ad] Endereço:Department of Laboratory Medicine, Severance Hospital, Yonsei University College of Medicine, Korea.
[Ti] Título:Ascorbate Oxidase Minimizes Interference by High-Concentration Ascorbic Acid in Total Cholesterol Assays.
[So] Source:Ann Lab Med;36(2):188-90, 2016 Mar.
[Is] ISSN:2234-3814
[Cp] País de publicação:Korea (South)
[La] Idioma:eng
[Mh] Termos MeSH primário: Ascorbato Oxidase/metabolismo
Ácido Ascórbico/química
Colesterol/sangue
Colorimetria
[Mh] Termos MeSH secundário: Idoso de 80 Anos ou mais
Ácido Ascórbico/administração & dosagem
Ácido Ascórbico/sangue
Neoplasias da Mama/patologia
Ensaios Enzimáticos
Feminino
Seres Humanos
Injeções Intravenosas
Intestino Delgado/cirurgia
Rim/fisiopatologia
Masculino
Meia-Idade
Cuidados Paliativos
Recidiva
[Pt] Tipo de publicação:CASE REPORTS; LETTER
[Nm] Nome de substância:
97C5T2UQ7J (Cholesterol); EC 1.10.3.3 (Ascorbate Oxidase); PQ6CK8PD0R (Ascorbic Acid)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170110
[Lr] Data última revisão:
170110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151229
[St] Status:MEDLINE
[do] DOI:10.3343/alm.2016.36.2.188


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[PMID]:26452908
[Au] Autor:Talalak K; Noiphung J; Songjaroen T; Chailapakul O; Laiwattanapaisal W
[Ad] Endereço:Clinical Biochemistry and Molecular Medicine, Faculty of Allied Health Sciences, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand.
[Ti] Título:A facile low-cost enzymatic paper-based assay for the determination of urine creatinine.
[So] Source:Talanta;144:915-21, 2015 Nov 01.
[Is] ISSN:1873-3573
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Creatinine is one of many markers used to investigate kidney function. This paper describes a low-cost enzymatic paper-based analytical device (enz-PAD) for determining urine creatinine. The disposable dead volumes of creatinine enzyme reagents from an automatic analyser cassette were utilised. Whatman No. 3 paper was cut into long rectangular shapes (4×40 mm(2)) on which the enzyme reagents, R1 and R2, were adsorbed in two consecutive regions. The assay was performed by immersing test strips into urine samples contained in microwells to allow creatinine in the sample to react with immobilised active ingredients and, then, traverse via capillary action to the detection area where chromogen products accumulated. The method is based on hydrogen peroxide (H2O2) formation via creatinine conversion using creatininase, creatinase, and sarcosine oxidase. The liberated H2O2 reacts with 4-aminophenazone and 2,4,6-triiodo-3-hydroxybenzoic acid to form quinoneimine with a pink-red colour at the detection zone. The linear range of the creatinine assay was 2.5-25 mg dL(-1) (r(2)=0.983), and the detection limit was 2.0 mg dL(-1). The colorimetric enz-PAD for the creatinine assay was highly correlated with a conventional alkaline picrate method when real urine samples were evaluated (r(2)=0.977; n=40). This simple and nearly zero-cost paper-based device provides a novel alternative method for screening urinary creatinine and will be highly beneficial for developing countries.
[Mh] Termos MeSH primário: Creatinina/urina
Ensaios Enzimáticos/métodos
Papel
[Mh] Termos MeSH secundário: Ascorbato Oxidase/química
Catalase/química
Colorimetria/métodos
Custos e Análise de Custo
Creatinina/química
Ensaios Enzimáticos/economia
Seres Humanos
Peroxidase/química
Sarcosina Oxidase/química
Ureo-Hidrolases/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
AYI8EX34EU (Creatinine); EC 1.10.3.3 (Ascorbate Oxidase); EC 1.11.1.6 (Catalase); EC 1.11.1.7 (Peroxidase); EC 1.5.3.1 (Sarcosine Oxidase); EC 3.5.3.- (Ureohydrolases); EC 3.5.3.3 (creatinase)
[Em] Mês de entrada:1607
[Cu] Atualização por classe:151010
[Lr] Data última revisão:
151010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151011
[St] Status:MEDLINE


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[PMID]:26244894
[Au] Autor:Joshi T; Graham B; Spiccia L
[Ad] Endereço:†School of Chemistry, Monash University, Victoria 3800, Australia.
[Ti] Título:Macrocyclic metal complexes for metalloenzyme mimicry and sensor development.
[So] Source:Acc Chem Res;48(8):2366-79, 2015 Aug 18.
[Is] ISSN:1520-4898
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Examples of proteins that incorporate one or more metal ions within their structure are found within a broad range of classes, including oxidases, oxidoreductases, reductases, proteases, proton transport proteins, electron transfer/transport proteins, storage proteins, lyases, rusticyanins, metallochaperones, sporulation proteins, hydrolases, endopeptidases, luminescent proteins, iron transport proteins, oxygen storage/transport proteins, calcium binding proteins, and monooxygenases. The metal coordination environment therein is often generated from residues inherent to the protein, small exogenous molecules (e.g., aqua ligands) and/or macrocyclic porphyrin units found, for example, in hemoglobin, myoglobin, cytochrome C, cytochrome C oxidase, and vitamin B12. Thus, there continues to be considerable interest in employing macrocyclic metal complexes to construct low-molecular weight models for metallobiosites that mirror essential features of the coordination environment of a bound metal ion without inclusion of the surrounding protein framework. Herein, we review and appraise our research exploring the application of the metal complexes formed by two macrocyclic ligands, 1,4,7-triazacyclononane (tacn) and 1,4,7,10-tetraazacyclododecane (cyclen), and their derivatives in biological inorganic chemistry. Taking advantage of the kinetic inertness and thermodynamic stability of their metal complexes, these macrocyclic scaffolds have been employed in the development of models that aid the understanding of metal ion-binding natural systems, and complexes with potential applications in biomolecule sensing, diagnosis, and therapy. In particular, the focus has been on "coordinatively unsaturated" metal complexes that incorporate a kinetically inert and stable metal-ligand moiety, but which also contain one or more weakly bound ligands, allowing for the reversible binding of guest molecules via the formation and dissociation of coordinate bonds. With regards to mimicking metallobiosites, examples are presented from our work on tacn-based complexes developed as simplified structural models for multimetallic enzyme sites. In particular, structural comparisons are made between multinuclear copper(II) complexes formed by such ligands and multicopper enzymes featuring type-2 and type-3 copper centers, such as ascorbate oxidase (AO) and laccase (Lc). Likewise, with the aid of relevant examples, we highlight the importance of cooperativity between either multiple metal centers or a metal center and a proximal auxiliary unit appended to the macrocyclic ligand in achieving efficient phosphate ester cleavage. Finally, the critical importance of the Zn(II)-imido and Zn(II)-phosphate interactions in Zn-cyclen-based systems for delivering highly sensitive electrochemical and fluorescent chemosensors is also showcased. The Account additionally highlights some of the factors that limit the performance of these synthetic nucleases and the practical application of the biosensors, and then identifies some avenues for the development of more effective macrocyclic constructs in the future.
[Mh] Termos MeSH primário: Materiais Biocompatíveis/química
Complexos de Coordenação/química
Metais/química
[Mh] Termos MeSH secundário: Ascorbato Oxidase/química
Ascorbato Oxidase/metabolismo
Materiais Biocompatíveis/metabolismo
Técnicas Biossensoriais
Complexos de Coordenação/metabolismo
Compostos Heterocíclicos/química
Lacase/química
Lacase/metabolismo
Ligantes
Conformação Molecular
Ribonucleases/química
Ribonucleases/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Biocompatible Materials); 0 (Coordination Complexes); 0 (Heterocyclic Compounds); 0 (Ligands); 0 (Metals); 4730-54-5 (1,4,7-triazacyclononane); 964584YO2O (cyclen); EC 1.10.3.2 (Laccase); EC 1.10.3.3 (Ascorbate Oxidase); EC 3.1.- (Ribonucleases)
[Em] Mês de entrada:1602
[Cu] Atualização por classe:161125
[Lr] Data última revisão:
161125
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150806
[St] Status:MEDLINE
[do] DOI:10.1021/acs.accounts.5b00142


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[PMID]:26220952
[Au] Autor:Ueda Y; Siddique S; Frei M
[Ad] Endereço:Institute of Crop Science and Resource Conservation, Plant Nutrition (Y.U., M.F.) and Molecular Phytomedicine (S.S.), University of Bonn, 53115 Bonn, Germany.
[Ti] Título:A Novel Gene, OZONE-RESPONSIVE APOPLASTIC PROTEIN1, Enhances Cell Death in Ozone Stress in Rice.
[So] Source:Plant Physiol;169(1):873-89, 2015 Sep.
[Is] ISSN:1532-2548
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A novel protein, OZONE-RESPONSIVE APOPLASTIC PROTEIN1 (OsORAP1), was characterized, which was previously suggested as a candidate gene underlying OzT9, a quantitative trait locus for ozone stress tolerance in rice (Oryza sativa). The sequence of OsORAP1 was similar to that of ASCORBATE OXIDASE (AO) proteins. It was localized in the apoplast, as shown by transient expression of an OsORAP1/green fluorescent protein fusion construct in Nicotiana benthamiana leaf epidermal and mesophyll cells, but did not possess AO activity, as shown by heterologous expression of OsORAP1 in Arabidopsis (Arabidopsis thaliana) mutants with reduced background AO activity. A knockout rice line of OsORAP1 showed enhanced tolerance to ozone stress (120 nL L(-1) average daytime concentration, 20 d), as demonstrated by less formation of leaf visible symptoms (i.e. cell death), less lipid peroxidation, and lower NADPH oxidase activity, indicating reduced active production of reactive oxygen species. In contrast, the effect of ozone on chlorophyll content was not significantly different among the lines. These observations suggested that OsORAP1 specifically induced cell death in ozone stress. Significantly enhanced expression of jasmonic acid-responsive genes in the knockout line implied the involvement of the jasmonic acid pathway in symptom mitigation. Sequence analysis revealed extensive polymorphisms in the promoter region of OsORAP1 between the ozone-susceptible cv Nipponbare and the ozone-tolerant cv Kasalath, the OzT9 donor variety, which could be responsible for the differential regulation of OsORAP1 reported earlier. These pieces of evidence suggested that OsORAP1 enhanced cell death in ozone stress, and its expression levels could explain the effect of a previously reported quantitative trait locus.
[Mh] Termos MeSH primário: Genes de Plantas
Oryza/citologia
Oryza/genética
Ozônio/farmacologia
Proteínas de Plantas/metabolismo
[Mh] Termos MeSH secundário: Ascorbato Oxidase/metabolismo
Sequência de Bases
Morte Celular/efeitos dos fármacos
Biologia Computacional
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
Técnicas de Inativação de Genes
Variação Genética
Modelos Biológicos
Dados de Sequência Molecular
Oryza/efeitos dos fármacos
Estresse Oxidativo/efeitos dos fármacos
Reguladores de Crescimento de Planta/metabolismo
Estômatos de Plantas/efeitos dos fármacos
Estômatos de Plantas/fisiologia
Transporte Proteico/efeitos dos fármacos
Locos de Características Quantitativas/genética
Transdução de Sinais/efeitos dos fármacos
Estresse Fisiológico/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Plant Growth Regulators); 0 (Plant Proteins); 66H7ZZK23N (Ozone); EC 1.10.3.3 (Ascorbate Oxidase)
[Em] Mês de entrada:1606
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150730
[St] Status:MEDLINE
[do] DOI:10.1104/pp.15.00956


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[PMID]:26051011
[Au] Autor:Zhang Z; Hao J; Xiao T; Yu P; Mao L
[Ad] Endereço:Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences (CAS), Beijing 100190, China. lqmao@iccas.ac.cn.
[Ti] Título:Online electrochemical systems for continuous neurochemical measurements with low-potential mediator-based electrochemical biosensors as selective detectors.
[So] Source:Analyst;140(15):5039-47, 2015 Aug 07.
[Is] ISSN:1364-5528
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:This study demonstrates a new strategy to develop online electrochemical systems (OECSs) for continuously monitoring neurochemicals by efficiently integrating in vivo microdialysis with an oxidase-based electrochemical biosensor with low-potential electron mediators to shuttle the electron transfer of the oxidases. By using thionine and xanthine oxidase (XOD) as examples of low-potential mediators and oxidases, respectively, we demonstrate that the use of low-potential mediators to shuttle the electron transfer of oxidases would offer a new approach to the development of oxidase-based biosensors with theoretical and technical simplicity. To construct the XOD-based biosensor, thionine was adsorbed onto carbon nanotubes and used to shuttle the electron transfer of XOD. The XOD-based biosensor was positioned into an electrochemical cell that was directly coupled with in vivo microdialysis to form an online electrochemical system (OECS) for continuous and selective measurements of the substrate of XOD (with hypoxanthine as an example). The OECS based on the low-potential mediators is highly selective against the species endogenously existing in the brain system, which is attributed to the low operation potential benefited from the low redox potentials of the mediators. Moreover, the OECS demonstrated here is stable and reproducible and could thus be envisaged to find some interesting applications in physiological and pathological investigations. This study essentially offers a new strategy to develop online electrochemical systems, which is of great importance in understanding the molecular basis of physiological and pathological events.
[Mh] Termos MeSH primário: Técnicas Biossensoriais/instrumentação
Química Encefálica
Enzimas Imobilizadas/metabolismo
Hipoxantina/análise
Dispositivos Lab-On-A-Chip
Xantina Oxidase/metabolismo
[Mh] Termos MeSH secundário: Adsorção
Animais
Ascorbato Oxidase/metabolismo
Cucurbita/enzimologia
Desenho de Equipamento
Microdiálise/instrumentação
Nanotubos de Carbono/química
Sistemas On-Line
Oxirredução
Fenotiazinas/metabolismo
Ratos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Enzymes, Immobilized); 0 (Nanotubes, Carbon); 0 (Phenothiazines); 2TN51YD919 (Hypoxanthine); EC 1.10.3.3 (Ascorbate Oxidase); EC 1.17.3.2 (Xanthine Oxidase); VTT2SAT5H0 (thionine)
[Em] Mês de entrada:1601
[Cu] Atualização por classe:150713
[Lr] Data última revisão:
150713
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150609
[St] Status:MEDLINE
[do] DOI:10.1039/c5an00593k



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