Base de dados : MEDLINE
Pesquisa : D08.811.682.047.150.270.500 [Categoria DeCS]
Referências encontradas : 524 [refinar]
Mostrando: 1 .. 10   no formato [Longo]

página 1 de 53 ir para página                         

  1 / 524 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
PMID:27770423
Autor:Milton RD
Endereço:Department of Chemistry, University of Utah, 315 S 1400 E, Rm 2020, Salt Lake City, UT, 84112, USA. rm7745@hotmail.co.uk.
Título:FAD-Dependent Glucose Dehydrogenase Immobilization and Mediation Within a Naphthoquinone Redox Polymer.
Fonte:Methods Mol Biol; 1504:193-202, 2017.
ISSN:1940-6029
País de publicação:United States
Idioma:eng
Resumo:Electrochemically-active polymers (redox polymers) are useful tools for simultaneous immobilization and electron transfer of enzymes at electrode surfaces, which also serve to increase the localized concentration of the biocatalyst. The properties of the employed redox couple must be compatible with the target biocatalyst from both an electrochemical (potential) and biochemical standpoint. This chapter details the synthesis of a naphthoquinone-functionalized redox polymer (NQ-LPEI) that is used to immobilize and electronically communicate with flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH), yielding an enzymatic bioanode that is able to deliver large catalytic current densities for glucose oxidation at a relatively low associated potential.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Enzymes, Immobilized); 0 (Naphthoquinones); 0 (Polymers); 146-14-5 (Flavin-Adenine Dinucleotide); EC 1.1.1.47 (Glucose 1-Dehydrogenase); IY9XDZ35W2 (Glucose)


  2 / 524 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
PMID:28832942
Autor:Marpani F; Sárossy Z; Pinelo M; Meyer AS
Endereço:Department of Chemical and Biochemical Engineering, Center for BioProcess Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark.
Título:Kinetics based reaction optimization of enzyme catalyzed reduction of formaldehyde to methanol with synchronous cofactor regeneration.
Fonte:Biotechnol Bioeng; 114(12):2762-2770, 2017 Dec.
ISSN:1097-0290
País de publicação:United States
Idioma:eng
Resumo:Enzymatic reduction of carbon dioxide (CO ) to methanol (CH OH) can be accomplished using a designed set-up of three oxidoreductases utilizing reduced pyridine nucleotide (NADH) as cofactor for the reducing equivalents electron supply. For this enzyme system to function efficiently a balanced regeneration of the reducing equivalents during reaction is required. Herein, we report the optimization of the enzymatic conversion of formaldehyde (CHOH) to CH OH by alcohol dehydrogenase, the final step of the enzymatic redox reaction of CO to CH OH, with kinetically synchronous enzymatic cofactor regeneration using either glucose dehydrogenase (System I) or xylose dehydrogenase (System II). A mathematical model of the enzyme kinetics was employed to identify the best reaction set-up for attaining optimal cofactor recycling rate and enzyme utilization efficiency. Targeted process optimization experiments were conducted to verify the kinetically modeled results. Repetitive reaction cycles were shown to enhance the yield of CH OH, increase the total turnover number (TTN) and the biocatalytic productivity rate (BPR) value for both system I and II whilst minimizing the exposure of the enzymes to high concentrations of CHOH. System II was found to be superior to System I with a yield of 8 mM CH OH, a TTN of 160 and BPR of 24 µmol CH OH/U · h during 6 hr of reaction. The study demonstrates that an optimal reaction set-up could be designed from rational kinetics modeling to maximize the yield of CH OH, whilst simultaneously optimizing cofactor recycling and enzyme utilization efficiency.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Coenzymes); 1HG84L3525 (Formaldehyde); EC 1.1.- (Alcohol Oxidoreductases); EC 1.1.1.1 (Alcohol Dehydrogenase); EC 1.1.1.175 (D-xylose dehydrogenase); EC 1.1.1.47 (Glucose 1-Dehydrogenase); Y4S76JWI15 (Methanol)


  3 / 524 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
PMID:28722796
Autor:Roth S; Präg A; Wechsler C; Marolt M; Ferlaino S; Lüdeke S; Sandon N; Wetzl D; Iding H; Wirz B; Müller M
Endereço:Institut für Pharmazeutische Wissenschaften, Albert-Ludwigs-Universität Freiburg, Albertstrasse 25, 79104, Freiburg, Germany.
Título:Extended Catalytic Scope of a Well-Known Enzyme: Asymmetric Reduction of Iminium Substrates by Glucose Dehydrogenase.
Fonte:Chembiochem; 18(17):1703-1706, 2017 Sep 05.
ISSN:1439-7633
País de publicação:Germany
Idioma:eng
Resumo:NADP(H)-dependent imine reductases (IREDs) are of interest in biocatalytic research due to their ability to generate chiral amines from imine/iminium substrates. In reaction protocols involving IREDs, glucose dehydrogenase (GDH) is generally used to regenerate the expensive cofactor NADPH by oxidation of d-glucose to gluconolactone. We have characterized different IREDs with regard to reduction of a set of bicyclic iminium compounds and have utilized H NMR and GC analyses to determine degree of substrate conversion and product enantiomeric excess (ee). All IREDs reduced the tested iminium compounds to the corresponding chiral amines. Blank experiments without IREDs also showed substrate conversion, however, thus suggesting an iminium reductase activity of GDH. This unexpected observation was confirmed by additional experiments with GDHs of different origin. The reduction of C=N bonds with good levels of conversion (>50 %) and excellent enantioselectivity (up to >99 % ee) by GDH represents a promiscuous catalytic activity of this enzyme.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Imines); 53-59-8 (NADP); EC 1.1.1.47 (Glucose 1-Dehydrogenase); IY9XDZ35W2 (Glucose)


  4 / 524 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
PMID:28243985
Autor:Chen J; Yan M; Xu L
Endereço:College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No.30 Puzhu Road, Nanjing, 211816, People's Republic of China.
Título:Efficient synthesis of (S)-N-Boc-3-hydroxypiperidine using an (R)-specific carbonyl reductase from Candida parapsilosis.
Fonte:World J Microbiol Biotechnol; 33(3):61, 2017 Mar.
ISSN:1573-0972
País de publicação:Germany
Idioma:eng
Resumo:(S)-N-Boc-3-hydroxypiperidine (S-NBHP) is a critical chiral intermediate in the synthesis of pharmaceuticals, including ibrutinib, the active pharmaceutical ingredient of the new drug Imbruvica approved for the treatment of lymphoma. An (R)-specific carbonyl reductase from Candida parapsilosis (CprCR, also known as R-specific alcohol dehydrogenase) that catalyzes asymmetric reduction to produce (S)-N-Boc-3-hydroxypiperidine (S-NBHP) was identified for the first time. When co-expressed with a glucose dehydrogenase from Bacillus megaterium in Escherichia coli Rosetta (DE3), recombinant crude enzyme exhibited an activity of 9 U/mg with N-Boc-3-piperidone as the substrate and 12 U/mg with glucose as the substrate. The biocatalysis of N-Boc-3-piperidone to S-NBHP using recombinant whole-cell biocatalysts was processed in a water/butyl acetate system as well as an aqueous monophasic system without extra NAD /NADH. This process showed great commercial potential, with a 100 g/l substrate concentration and a whole cells loading (w/v) of 10%, with the conversion of 97.8% and an e.e. of 99.8% in an aqueous monophasic system.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Fungal Proteins); 0 (Piperidines); 0 (Recombinant Proteins); EC 1.1.1.1 (Alcohol Dehydrogenase); EC 1.1.1.47 (Glucose 1-Dehydrogenase)


  5 / 524 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
PMID:28092733
Autor:Liu ZQ; Dong SC; Yin HH; Xue YP; Tang XL; Zhang XJ; He JY; Zheng YG
Endereço:Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, PR China.
Título:Enzymatic synthesis of an ezetimibe intermediate using carbonyl reductase coupled with glucose dehydrogenase in an aqueous-organic solvent system.
Fonte:Bioresour Technol; 229:26-32, 2017 Apr.
ISSN:1873-2976
País de publicação:England
Idioma:eng
Resumo:(4S)-3-[(5S)-5-(4-Fluorophenyl)-5-hydroxypentanoyl]-4-phenyl-1,3-oxazolidin-2-one ((S)-ET-5) is an important chiral intermediate in the synthesis of chiral side chain of ezetimibe. Recombinant Escherichia coli expressing carbonyl reductase (CBR) was successfully constructed in this study. The total E. coli biomass and the specific activity of recombinant CBR in 5L fermenter culture were 10.9gDCWL and 14900.3Ug DCW, respectively. The dual-enzyme coupled biocatalytic process in an aqueous-organic biphasic solvent system was first constructed using p-xylene as the optimal organic phase under optimized reaction conditions, and 150gL (4S)-3-[5-(4-fluorophenyl)-1,5-dioxophentyl]-4-phenyl-1,3-oxazolidin-2-one (ET-4) was successfully converted to (S)-ET-5 with a conversion of 99.1% and diastereomeric excess of 99% after 24-h, which are the highest values reported to date for the production of (S)-ET-5.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Buffers); 0 (Recombinant Proteins); 0 (Solvents); 059QF0KO0R (Water); 53-59-8 (NADP); EC 1.1.- (Alcohol Oxidoreductases); EC 1.1.1.47 (Glucose 1-Dehydrogenase); EOR26LQQ24 (Ezetimibe); IY9XDZ35W2 (Glucose)


  6 / 524 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
PMID:28011130
Autor:Cui ZM; Zhang JD; Fan XJ; Zheng GW; Chang HH; Wei WL
Endereço:Department of Biological and Pharmaceutical Engineering, College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan, Shanxi, 030024, PR China.
Título:Highly efficient bioreduction of 2-hydroxyacetophenone to (S)- and (R)-1-phenyl-1,2-ethanediol by two substrate tolerance carbonyl reductases with cofactor regeneration.
Fonte:J Biotechnol; 243:1-9, 2017 Feb 10.
ISSN:1873-4863
País de publicação:Netherlands
Idioma:eng
Resumo:Optically pure 1-phenyl-1,2-ethanediol is a very important chiral building block and intermediate in fine chemical and pharmaceutical industries. Reduction of 2-hydroxyacetophenone provides a straightforward approach to access these important compounds. In this study, two enantiocomplementary carbonyl reductases, BDHA (2,3-butanediol dehydrogenase from Bacillus subtilis) and GoSCR (polyol dehydrogenase from Gluconobacter oxydans) were discovered for the first time to convert 2-hydroxyacetophenone (2-HAP) to (R)-1-phenyl-1,2-ethanediol ((R)-PED) and (S)-1-phenyl-1,2-ethanediol ((S)-PED) with excellent stereochemical selectivity, respectively. The two enzymes were purified and characterized. In vitro bioreduction of 2-HAP catalyzed by BDHA and GoSCR coupled with glucose dehydrogenase (GDH) from Bacillus subtilis for cofactor regeneration were demonstrated, affording both (R)-PED and (S)-PED in>99% ee and 99% conversion. Recombinant Escherichia coli whole cells co-expressing both GDH and BDHA or GoSCR genes were used to asymmetric reduction of 2-HAP to (R)-PED or (S)-PED. Under the optimized conditions, the bioreduction of 400mM (54g/L) substrate was proceeded smoothly without the external addition of cofactor, and the product (R)-PED and (S)-PED were obtained with 99% yield, >99% ee and 18.0g/L/h volumetric productivity. These results offer a practical biocatalytic method for the preparation of both (R)-PED and (S)-PED with high volumetric productivity.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Acetophenones); 0 (Butylene Glycols); 0 (Escherichia coli Proteins); 0 (Ethylene Glycols); 0 (Molecular Chaperones); 2ZAC511UK8 (styrene glycol); 3E533Z76W0 (2'-hydroxyacetophenone); 45427ZB5IJ (2,3-butylene glycol); EC 1.1.- (Alcohol Oxidoreductases); EC 1.1.1.14 (L-Iditol 2-Dehydrogenase); EC 1.1.1.47 (Glucose 1-Dehydrogenase)


  7 / 524 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
PMID:27838320
Autor:Hu X; Liu L; Chen D; Wang Y; Zhang J; Shao L
Endereço:State Key Laboratory of New Drug and Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, 285 Gebaini Rd., Shanghai 200040, China; School of Engineering, China Pharmaceutical University, Nanjing 210009, China.
Título:Co-expression of the recombined alcohol dehydrogenase and glucose dehydrogenase and cross-linked enzyme aggregates stabilization.
Fonte:Bioresour Technol; 224:531-535, 2017 Jan.
ISSN:1873-2976
País de publicação:England
Idioma:eng
Resumo:As the key chiral precursor of Crizotinib (S)-1-(2,6-dichloro-3-fluorophenyl) phenethyl alcohol can be prepared from 1-(2,6-dichloro-3-fluorophenyl) acetophenone by the reductive coupling reactions of alcohol dehydrogenase (ADH) and glucose dehydrogenases (GDH). In this work the heterologous expression plasmids harbouring the encoding genes of ADH and GDH were constructed respectively and co-expressed in the same E. coli strain. After optimization, a co-cross-linked enzyme aggregates (co-CLEAs) of both ADH and GDH were prepared from crude enzyme extracts by cross-linking with the mass ratio of Tween 80, glutaraldehyde and total protein (0.6:1:2) which rendered immobilized biocatalysts that retained 81.90% (ADH) and 40.29% (GDH) activity retention. The ADH/GDH co-CLEAs show increased thermal stability and pH stability compared to both enzymes. The ADH/GDH co-CLEAs also show 80% (ADH) and 87% (GDH) residual activity after seven cycles of repeated use. These results make the ADH/GDH co-CLEAs a potential biocatalyst for the industrial preparation of (S)-1-(2,6-dichloro-3-fluorophenyl) phenethyl alcohol.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Cross-Linking Reagents); 0 (Enzymes, Immobilized); 0 (Polysorbates); 0 (Pyrazoles); 0 (Pyridines); 0 (Recombinant Proteins); 53AH36668S (crizotinib); EC 1.1.1.1 (Alcohol Dehydrogenase); EC 1.1.1.47 (Glucose 1-Dehydrogenase); ML9LGA7468 (Phenylethyl Alcohol); T3C89M417N (Glutaral)


  8 / 524 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
PMID:27825524
Autor:González-Guerrero MJ; Del Campo FJ; Esquivel JP; Leech D; Sabaté N
Endereço:Instituto de Microelectrónica de Barcelona, IMB-CNM (CSIC), Campus de la Universidad Autónoma de Barcelona (Esfera UAB), Bellaterra, 08193 Barcelona, España. Electronic address: mariajose.gonzalez@imb-cnm.csic.es.
Título:Paper-based microfluidic biofuel cell operating under glucose concentrations within physiological range.
Fonte:Biosens Bioelectron; 90:475-480, 2017 Apr 15.
ISSN:1873-4235
País de publicação:England
Idioma:eng
Resumo:This work addresses the development of a compact paper-based enzymatic microfluidic glucose/O fuel cell that can operate using a very limited sample volume (≈35µl) and explores the energy generated by glucose at concentrations typically found in blood samples at physiological conditions (pH 7.4). Carbon paper electrodes combined with a paper sample absorption substrate all contained within a plastic microfluidic casing are used to construct the paper-based fuel cell. The anode catalysts consist of glucose dehydrogenase and [Os(4,4'-dimethoxy-2,2'-bipyridine) (poly-vinylimidazole) Cl] as mediator, while the cathode catalysts were bilirubin oxidase and [Os(2,2'-bipyridine) (poly-vinylimidazole) Cl] as mediator. The fuel cell delivered a linear power output response to glucose over the range of 2.5-30mM, with power densities ranging from 20 to 90µWcm . The quantification of the available electrical power as well as the energy density extracted from small synthetic samples allows planning potential uses of this energy to power different sensors and analysis devices in a wide variety of in-vitro applications.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Enzymes, Immobilized); 0 (Imidazoles); 7440-44-0 (Carbon); EC 1.1.1.47 (Glucose 1-Dehydrogenase); EC 1.10.3.2 (Laccase); IY9XDZ35W2 (Glucose); S88TT14065 (Oxygen)


  9 / 524 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
PMID:27743864
Autor:Lee I; Sode T; Loew N; Tsugawa W; Lowe CR; Sode K
Endereço:Department of Industrial Technology and Innovation, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, Japan.
Título:Continuous operation of an ultra-low-power microcontroller using glucose as the sole energy source.
Fonte:Biosens Bioelectron; 93:335-339, 2017 Jul 15.
ISSN:1873-4235
País de publicação:England
Idioma:eng
Resumo:An ultimate goal for those engaged in research to develop implantable medical devices is to develop mechatronic implantable artificial organs such as artificial pancreas. Such devices would comprise at least a sensor module, an actuator module, and a controller module. For the development of optimal mechatronic implantable artificial organs, these modules should be self-powered and autonomously operated. In this study, we aimed to develop a microcontroller using the BioCapacitor principle. A direct electron transfer type glucose dehydrogenase was immobilized onto mesoporous carbon, and then deposited on the surface of a miniaturized Au electrode (7mm ) to prepare a miniaturized enzyme anode. The enzyme fuel cell was connected with a 100 µF capacitor and a power boost converter as a charge pump. The voltage of the enzyme fuel cell was increased in a stepwise manner by the charge pump from 330mV to 3.1V, and the generated electricity was charged into a 100µF capacitor. The charge pump circuit was connected to an ultra-low-power microcontroller. Thus prepared BioCapacitor based circuit was able to operate an ultra-low-power microcontroller continuously, by running a program for 17h that turned on an LED every 60s. Our success in operating a microcontroller using glucose as the sole energy source indicated the probability of realizing implantable self-powered autonomously operated artificial organs, such as artificial pancreas.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:EC 1.1.1.47 (Glucose 1-Dehydrogenase); IY9XDZ35W2 (Glucose)


  10 / 524 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
Texto completo
PMID:27666367
Autor:Lee J; Yoshida W; Abe K; Nakabayashi K; Wakeda H; Hata K; Marquette CA; Blum LJ; Sode K; Ikebukuro K
Endereço:Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16 Naka-Cho, Koganei, Tokyo 184-8588, Japan.
Título:Development of an electrochemical detection system for measuring DNA methylation levels using methyl CpG-binding protein and glucose dehydrogenase-fused zinc finger protein.
Fonte:Biosens Bioelectron; 93:118-123, 2017 Jul 15.
ISSN:1873-4235
País de publicação:England
Idioma:eng
Resumo:DNA methylation level at a certain gene region is considered as a new type of biomarker for diagnosis and its miniaturized and rapid detection system is required for diagnosis. Here we have developed a simple electrochemical detection system for DNA methylation using methyl CpG-binding domain (MBD) and a glucose dehydrogenase (GDH)-fused zinc finger protein. This analytical system consists of three steps: (1) methylated DNA collection by MBD, (2) PCR amplification of a target genomic region among collected methylated DNA, and (3) electrochemical detection of the PCR products using a GDH-fused zinc finger protein. With this system, we have successfully measured the methylation levels at the promoter region of the androgen receptor gene in 10 copies of genomic DNA extracted from PC3 and TSU-PR1 cancer cell lines. Since no sequence analysis or enzymatic digestion is required for this detection system, DNA methylation levels can be measured within 3h with a simple procedure.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (DNA-Binding Proteins); 9007-49-2 (DNA); EC 1.1.1.47 (Glucose 1-Dehydrogenase)



página 1 de 53 ir para página                         
   


Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde