Base de dados : MEDLINE
Pesquisa : D08.811.682.047.150 [Categoria DeCS]
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  1 / 1159 MEDLINE  
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[PMID]:29199984
[Au] Autor:Law A; Stergioulis A; Halavaty AS; Minasov G; Anderson WF; Kuhn ML
[Ad] Endereço:Department of Chemistry and Biochemistry, San Francisco State University, USA.
[Ti] Título:Structure of the Bacillus anthracis dTDP-L-rhamnose-biosynthetic enzyme dTDP-4-dehydrorhamnose reductase (RfbD).
[So] Source:Acta Crystallogr F Struct Biol Commun;73(Pt 12):644-650, 2017 Dec 01.
[Is] ISSN:2053-230X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacillus anthracis is the causative agent of the deadly disease Anthrax. Its use in bioterrorism and its ability to re-emerge have brought renewed interest in this organism. B. anthracis is a Gram-positive bacterium that adds L-rhamnose to its cell-wall polysaccharides using the activated donor dTDP-ß-L-rhamnose. The enzymes involved in the biosynthesis of the activated donor are absent in humans, which make them ideal targets for therapeutic development to combat pathogens. Here, the 2.65 Šresolution crystal structure of the fourth enzyme in the dTDP-ß-L-rhamnose-biosynthetic pathway from B. anthracis, dTDP-4-dehydro-ß-L-rhamnose reductase (RfbD), is presented in complex with NADP . This enzyme catalyzes the reduction of dTDP-4-dehydro-ß-L-rhamnose to dTDP-ß-L-rhamnose. Although the protein was co-crystallized in the presence of Mg , the protein lacks the conserved residues that coordinate Mg .
[Mh] Termos MeSH primário: Bacillus anthracis/enzimologia
Proteínas de Bactérias/química
Desidrogenases de Carboidrato/química
Desidrogenases de Carboidrato/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Desidrogenases de Carboidrato/genética
Cristalografia por Raios X
Magnésio/metabolismo
Modelos Moleculares
NADP/química
NADP/metabolismo
Açúcares de Nucleosídeo Difosfato/metabolismo
Conformação Proteica
Multimerização Proteica
Homologia Estrutural de Proteína
Especificidade por Substrato
Nucleotídeos de Timina/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Nucleoside Diphosphate Sugars); 0 (Thymine Nucleotides); 2147-59-3 (thymidine diphosphate rhamnose); 53-59-8 (NADP); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.1.133 (dTDP-4-dehydrorhamnose reductase); I38ZP9992A (Magnesium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171205
[St] Status:MEDLINE
[do] DOI:10.1107/S2053230X17015746


  2 / 1159 MEDLINE  
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[PMID]:28751144
[Au] Autor:Yao F; Chen L; Fan Z; Teng F; Zhao Y; Guan F; Zhang M; Liu Y
[Ad] Endereço:Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
[Ti] Título:Interplay between H6PDH and 11ß-HSD1 implicated in the pathogenesis of type 2 diabetes mellitus.
[So] Source:Bioorg Med Chem Lett;27(17):4107-4113, 2017 09 01.
[Is] ISSN:1464-3405
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Extensive studies have been performed on the role of 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) in metabolic diseases. Our previous study reported glucose could directly regulate hexose-6-phosphate dehydrogenase (H6PDH) and 11ß-HSD1. Recently, we further investigated the interplay of H6PDH and 11ß-HSD1 and their roles in hepatic gluconeogenesis and insulin resistance to elucidate the importance of H6PDH and 11ß-HSD1 in pathogenesis of type 2 diabetes mellitus (T2DM). T2DM rats model and H6PDH or 11ß-HSD1 siRNA transfected in CBRH-7919 cells were used to explore the effect of H6PDH and 11ß-HSD1 in T2DM. The results showed that the expression and activity of H6PDH and 11ß-HSD1 in livers of diabetic rats were increased, with the expressions of PEPCK and G6Pase or liver corticosterone increased apparently. It also showed that H6PDH siRNA and 11ß-HSD1 siRNA could inhibit the protein expression and enzyme activity by each other. With H6PDH siRNA, the enhancement of gluconeogenesis was blocked and insulin resistance stimulated by corticosterone was reduced. H6PDH and 11ß-HSD1 might be the effective and prospective targets for T2DM and metabolic syndromes, based on the interplay between these two enzymes.
[Mh] Termos MeSH primário: 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo
Desidrogenases de Carboidrato/metabolismo
Diabetes Mellitus Experimental/enzimologia
Diabetes Mellitus Tipo 2/enzimologia
[Mh] Termos MeSH secundário: Animais
Linhagem Celular Tumoral
Corticosterona/análise
Corticosterona/farmacologia
Diabetes Mellitus Experimental/genética
Diabetes Mellitus Experimental/metabolismo
Diabetes Mellitus Tipo 2/genética
Diabetes Mellitus Tipo 2/metabolismo
Modelos Animais de Doenças
Glucose/metabolismo
Fígado/metabolismo
Ratos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.1.- (galactose-6-phosphate dehydrogenase); EC 1.1.1.146 (11-beta-Hydroxysteroid Dehydrogenase Type 1); IY9XDZ35W2 (Glucose); W980KJ009P (Corticosterone)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171125
[Lr] Data última revisão:
171125
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170729
[St] Status:MEDLINE


  3 / 1159 MEDLINE  
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[PMID]:28670679
[Au] Autor:Lugsanangarm K; Nueangaudom A; Pianwanit S; Kokpol S; Nunthaboot N; Tanaka F; Taniguchi S; Chosrowjan H
[Ad] Endereço:Program of Chemistry, Faculty of Science and Technology, Bansomdejchaopraya Rajabhat University, Bangkok, 10600, Thailand.
[Ti] Título:Dynamics of the protein structure of T169S pyranose 2-oxidase in solution: Molecular dynamics simulation.
[So] Source:Proteins;85(10):1913-1924, 2017 Oct.
[Is] ISSN:1097-0134
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Pyranose 2-oxidase (P2O) from Trametes multicolor contains FAD as cofactor, and forms a tetramer. The protein structure of a mutated P2O, T169S (Thr169 is replaced by Ser), in solution was studied by means of molecular dynamics simulation and analyses of photoinduced electron transfer (ET) from Trp168 to excited isoalloxazine (Iso*), and was compared with wild type (WT) P2O. Hydrogen bonding between Iso and nearby amino acids was very similar as between T169S and WT protein. Distances between Iso and Tyr456 were extremely heterogeneous among the subunits, 1.7 (1.5 in WT) in subunit A (Sub A), 0.97 (2.2 in WT) in Sub B, 1.3 (2.1 in WT) in Sub C, 1.3 nm (2.0 in WT) in Sub D. Mean values of root of mean square fluctuation over all residues were greater by four times than those in WT. This suggests that the protein structure of T169S is much more flexible than that of WT. Electrostatic (ES) energies between Iso anion in one subunit and ionic groups in the entire protein were evaluated. It was found that more than 50% of the total ES energy in each subunit is contributed from other subunits. Reported fluorescence decays were analyzed by a method as WT, previously reported. Electron affinities of Iso* in T169S were appreciably higher than those in WT. Static dielectric constants near Iso and Trp168 were also quite higher in T169S than those in WT.
[Mh] Termos MeSH primário: Aminoácidos/química
Desidrogenases de Carboidrato/química
Conformação Proteica
Soluções/química
[Mh] Termos MeSH secundário: Aminoácidos/genética
Ligações de Hidrogênio
Simulação de Dinâmica Molecular
Trametes/química
Trametes/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids); 0 (Solutions); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.3.10 (pyranose oxidase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170704
[St] Status:MEDLINE
[do] DOI:10.1002/prot.25345


  4 / 1159 MEDLINE  
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[PMID]:28293739
[Au] Autor:Ebert MB; Mülller MI; Marigo J; Valente ALS; Cremer MJ; da Silva RJ
[Ad] Endereço:Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, São Paulo, 18618-689, Brazil. mbe.bio@gmail.com.
[Ti] Título:A new Synthesium species (Digenea: Brachycladiidae) from the bottlenose dolphin Tursiops truncatus (Cetacea: Delphinidae) in Southwestern Atlantic waters.
[So] Source:Parasitol Res;116(5):1443-1452, 2017 May.
[Is] ISSN:1432-1955
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:A new species of Synthesium from the bottlenose dolphin Tursiops truncatus in South Brazilian waters is described. Morphological and molecular identification was performed, and phylogenetic analyses were carried out using the ribosomal small subunit and internal transcribed spacer 1 and the mitochondrial NDH dehydrogenase subunit 3 and cytochrome c oxidase subunit 1 genes. The main characteristics of the new species are the subterminal round-shaped oral sucker, the anterior distribution of vitellaria reaching the level of the ovary and the oval-shaped testes. The results obtained with the molecular markers supported the inclusion of the specimens into the genus Synthesium. The nucleotide divergence detected for the mitochondrial genes among the new species and others of the same genus supported the erection of a new species. This is the ninth species assigned to the genus and the third Synthesium species recorded in the South Atlantic Ocean.
[Mh] Termos MeSH primário: Golfinho Nariz-de-Garrafa/parasitologia
Trematódeos/classificação
Trematódeos/isolamento & purificação
Infecções por Trematódeos/veterinária
[Mh] Termos MeSH secundário: Animais
Oceano Atlântico
Brasil
Desidrogenases de Carboidrato/genética
DNA Intergênico/genética
Complexo IV da Cadeia de Transporte de Elétrons/genética
Feminino
Masculino
Filogenia
Subunidades Ribossômicas Menores/genética
Trematódeos/genética
Infecções por Trematódeos/parasitologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Intergenic); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.1.29 (Glycerate dehydrogenase); EC 1.9.3.1 (Electron Transport Complex IV)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171007
[Lr] Data última revisão:
171007
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170316
[St] Status:MEDLINE
[do] DOI:10.1007/s00436-017-5421-2


  5 / 1159 MEDLINE  
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[PMID]:28245812
[Au] Autor:Ma S; Preims M; Piumi F; Kappel L; Seiboth B; Record E; Kracher D; Ludwig R
[Ad] Endereço:Department of Food Sciences and Technology, Vienna Institute of Biotechnology, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria.
[Ti] Título:Molecular and catalytic properties of fungal extracellular cellobiose dehydrogenase produced in prokaryotic and eukaryotic expression systems.
[So] Source:Microb Cell Fact;16(1):37, 2017 Feb 28.
[Is] ISSN:1475-2859
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Cellobiose dehydrogenase (CDH) is an extracellular enzyme produced by lignocellulolytic fungi. cdh gene expression is high in cellulose containing media, but relatively low CDH concentrations are found in the supernatant of fungal cultures due to strong binding to cellulose. Therefore, heterologous expression of CDH in Pichia pastoris was employed in the last 15 years, but the obtained enzymes were over glycosylated and had a reduced specific activity. RESULTS: We compare the well-established CDH expression host P. pastoris with the less frequently used hosts Escherichia coli, Aspergillus niger, and Trichoderma reesei. The study evaluates the produced quantity and protein homogeneity of Corynascus thermophilus CDH in the culture supernatants, the purification, and finally compares the enzymes in regard to cofactor loading, glycosylation, catalytic constants and thermostability. CONCLUSIONS: Whereas E. coli could only express the catalytic dehydrogenase domain of CDH, all eukaryotic hosts could express full length CDH including the cytochrome domain. The CDH produced by T. reesei was most similar to the CDH originally isolated from the fungus C. thermophilus in regard to glycosylation, cofactor loading and catalytic constants. Under the tested experimental conditions the fungal expression hosts produce CDH of superior quality and uniformity compared to P. pastoris.
[Mh] Termos MeSH primário: Aspergillus niger/genética
Desidrogenases de Carboidrato/genética
Desidrogenases de Carboidrato/metabolismo
Escherichia coli/genética
Expressão Gênica
Trichoderma/genética
[Mh] Termos MeSH secundário: Aspergillus niger/enzimologia
Desidrogenases de Carboidrato/isolamento & purificação
Catálise
Meios de Cultura/química
Estabilidade Enzimática
Escherichia coli/enzimologia
Glicosilação
Cinética
Pichia/enzimologia
Pichia/genética
Proteínas Recombinantes/metabolismo
Sordariales/enzimologia
Temperatura Ambiente
Trichoderma/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Culture Media); 0 (Recombinant Proteins); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.99.18 (cellobiose-quinone oxidoreductase)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170420
[Lr] Data última revisão:
170420
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170302
[St] Status:MEDLINE
[do] DOI:10.1186/s12934-017-0653-5


  6 / 1159 MEDLINE  
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[PMID]:28236756
[Au] Autor:Lamberg P; Hamit-Eminovski J; Toscano MD; Eicher-Lorka O; Niaura G; Arnebrant T; Shleev S; Ruzgas T
[Ad] Endereço:Department of Chemistry, University of Rochester, 14611 Rochester, NY, USA. Electronic address: plamberg@ur.rochester.edu.
[Ti] Título:Electrical activity of cellobiose dehydrogenase adsorbed on thiols: Influence of charge and hydrophobicity.
[So] Source:Bioelectrochemistry;115:26-32, 2017 Jun.
[Is] ISSN:1878-562X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The interface between protein and material surface is of great research interest in applications varying from implants, tissue engineering to bioelectronics. Maintaining functionality of bioelements depends greatly on the immobilization process. In the present study direct electron transfer of cellobiose dehydrogenase from Humicola insolens (HiCDH), adsorbed on four different self-assembled monolayers (SAMs) formed by 5-6 chain length carbon thiols varying in terminal group structure was investigated. By using a combination of quartz crystal microbalance with dissipation, ellipsometry and electrochemistry the formation and function of the HiCDH film was studied. It was found that the presence of charged pyridinium groups was needed to successfully establish direct electron contact between the enzyme and electrode. SAMs formed from hydrophilic charged thiols achieved nearly two times higher current densities compared to hydrophobic charged thiols. Additionally, the results also indicated proportionality between HiCDH catalytic constant and water content of the enzyme film. Enzyme films on charged pyridine thiols had smaller variations in water content and viscoelastic properties than films adsorbed on the more hydrophobic thiols. This work highlights several perspectives on the underlying factors affecting performance of immobilized HiCDH.
[Mh] Termos MeSH primário: Desidrogenases de Carboidrato/química
Desidrogenases de Carboidrato/metabolismo
Compostos de Sulfidrila/química
[Mh] Termos MeSH secundário: Adsorção
Ascomicetos/enzimologia
Catálise
Elasticidade
Eletroquímica/métodos
Enzimas Imobilizadas/química
Enzimas Imobilizadas/metabolismo
Ouro/química
Interações Hidrofóbicas e Hidrofílicas
Técnicas de Microbalança de Cristal de Quartzo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Enzymes, Immobilized); 0 (Sulfhydryl Compounds); 7440-57-5 (Gold); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.99.18 (cellobiose-quinone oxidoreductase)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170321
[Lr] Data última revisão:
170321
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170226
[St] Status:MEDLINE


  7 / 1159 MEDLINE  
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[PMID]:28193332
[Au] Autor:Gonaus C; Maresch D; Schropp K; Ó Conghaile P; Leech D; Gorton L; Peterbauer CK
[Ad] Endereço:Department of Food Sciences and Technology, BOKU-University of Natural Resources and Life Sciences Vienna, Muthgasse 18, A-1190 Wien, Austria; Department of Analytical Chemistry/Biochemistry and Structural Biology, Lund University, PO Box 124, SE-221 00 Lund, Sweden.
[Ti] Título:Analysis of Agaricus meleagris pyranose dehydrogenase N-glycosylation sites and performance of partially non-glycosylated enzymes.
[So] Source:Enzyme Microb Technol;99:57-66, 2017 Apr.
[Is] ISSN:1879-0909
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Pyranose Dehydrogenase 1 from the basidiomycete Agaricus meleagris (AmPDH1) is an oxidoreductase capable of oxidizing a broad variety of sugars. Due to this and its ability of dioxidation of substrates and no side production of hydrogen peroxide, it is studied for use in enzymatic bio-fuel cells. In-vitro deglycosylated AmPDH1 as well as knock-out mutants of the N-glycosylation sites N and N , near the active site entrance, were previously shown to improve achievable current densities of graphite electrodes modified with AmPDH1 and an osmium redox polymer acting as a redox mediator, up to 10-fold. For a better understanding of the role of N-glycosylation of AmPDH1, a systematic set of N-glycosylation site mutants was investigated in this work, regarding expression efficiency, enzyme activity and stability. Furthermore, the site specific extend of N-glycosylation was compared between native and recombinant wild type AmPDH1. Knocking out the site N prevented the attachment of significantly extended N-glycan structures as detected on polyacrylamide gel electrophoresis, but did not significantly alter enzyme performance on modified electrodes. This suggests that not the molecule size but other factors like accessibility of the active site improved performance of deglycosylated AmPDH1/osmium redox polymer modified electrodes. A fourth N-glycosylation site of AmPDH1 could be confirmed by mass spectrometry at N , which appeared to be conserved in related fungal pyranose dehydrogenases but not in other members of the glucose-methanol-choline oxidoreductase structural family. This site was shown to be the only one that is essential for functional recombinant expression of the enzyme.
[Mh] Termos MeSH primário: Agaricus/enzimologia
Desidrogenases de Carboidrato/química
Desidrogenases de Carboidrato/metabolismo
Proteínas Fúngicas/química
Proteínas Fúngicas/metabolismo
[Mh] Termos MeSH secundário: Agaricus/genética
Substituição de Aminoácidos
Sítios de Ligação/genética
Desidrogenases de Carboidrato/genética
Domínio Catalítico/genética
Estabilidade Enzimática
Proteínas Fúngicas/genética
Glicosilação
Cinética
Modelos Moleculares
Mutagênese Sítio-Dirigida
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fungal Proteins); 0 (Recombinant Proteins); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.3.10 (pyranose oxidase)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170724
[Lr] Data última revisão:
170724
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170215
[St] Status:MEDLINE


  8 / 1159 MEDLINE  
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[PMID]:28062914
[Au] Autor:Tafoukt D; Soric A; Sigoillot JC; Ferrasse JH
[Ad] Endereço:Aix Marseille Univ, CNRS, Centrale Marseille, M2P2, Marseille, France.
[Ti] Título:Determination of kinetics and heat of hydrolysis for non-homogenous substrate by isothermal calorimetry.
[So] Source:Bioprocess Biosyst Eng;40(4):643-650, 2017 Apr.
[Is] ISSN:1615-7605
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:The competitiveness of the second-generation bioethanol by biotechnological process requires an effective and quantitative control of biochemical reactions. In this study, the potential of isothermal calorimetry technique to measure heat and kinetics of a non-homogeneous substrate enzymatic hydrolysis is intended. Using this technique, optimum temperature of the enzymes used for lignocellulosic molecules hydrolysis was determined. Thus, the amount of substrate-to-enzyme ratio was highlighted as an important parameter of the hydrolysis yield. Furthermore, a new enzymes' cocktail efficiency consisting of a mix of cellulases and cellobiose dehydrogenase (CDH) was qualified by this technique. The results showed that this cocktail allowed the production of a high amount of gluconic acid that could improve the attractiveness of these second-generation biofuels. From the set of experiments, the hydrolysis heat of wheat straw was derived and a meaningful value of -32.2 ± 3.2 J g (gram reducing sugars product) is calculated. Then, isothermal measurements were used to determine kinetic constants of the cellulases and CDH mix on wheat straw. Results showed that this enzyme cocktail has an optimal rate at 45 °C in the range of temperatures tested (40-55 °C).
[Mh] Termos MeSH primário: Biocombustíveis
Desidrogenases de Carboidrato/química
Celulase/química
Etanol/química
Temperatura Alta
Triticum/química
[Mh] Termos MeSH secundário: Calorimetria
Hidrólise
Cinética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biofuels); 3K9958V90M (Ethanol); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.99.18 (cellobiose-quinone oxidoreductase); EC 3.2.1.4 (Cellulase)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170428
[Lr] Data última revisão:
170428
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170108
[St] Status:MEDLINE
[do] DOI:10.1007/s00449-016-1728-0


  9 / 1159 MEDLINE  
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[PMID]:27995309
[Au] Autor:Graf MM; Weber S; Kracher D; Kittl R; Sygmund C; Ludwig R; Peterbauer C; Haltrich D
[Ad] Endereço:Food Biotechnology Laboratory, Department of Food Science and Technology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190, Vienna, Austria.
[Ti] Título:Characterization of three pyranose dehydrogenase isoforms from the litter-decomposing basidiomycete Leucoagaricus meleagris (syn. Agaricus meleagris).
[So] Source:Appl Microbiol Biotechnol;101(7):2879-2891, 2017 Apr.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Multigenicity is commonly found in fungal enzyme systems, with the purpose of functional compensation upon deficiency of one of its members or leading to enzyme isoforms with new functionalities through gene diversification. Three genes of the flavin-dependent glucose-methanol-choline (GMC) oxidoreductase pyranose dehydrogenase (AmPDH) were previously identified in the litter-degrading fungus Agaricus (Leucoagaricus) meleagris, of which only AmPDH1 was successfully expressed and characterized. The aim of this work was to study the biophysical and biochemical properties of AmPDH2 and AmPDH3 and compare them with those of AmPDH1. AmPDH1, AmPDH2 and AmPDH3 showed negligible oxygen reactivity and possess a covalently tethered FAD cofactor. All three isoforms can oxidise a range of different monosaccarides and oligosaccharides including glucose, mannose, galactose and xylose, which are the main constituent sugars of cellulose and hemicelluloses, and judging from the apparent steady-state kinetics determined for these sugars, the three isoforms do not show significant differences pertaining to their reaction with sugar substrates. They oxidize glucose both at C2 and C3 and upon prolonged reaction C2 and C3 double-oxidized glucose is obtained, confirming that the A. meleagris genes pdh2 (AY753308.1) and pdh3 (DQ117577.1) indeed encode CAZy class AA3_2 pyranose dehydrogenases. While reactivity with electron donor substrates was comparable for the three AmPDH isoforms, their kinetic properties differed significantly for the model electron acceptor substrates tested, a radical (the 2,2'-azino-bis[3-ethylbenzothiazoline-6-sulphonic acid] cation radical), a quinone (benzoquinone) and a complexed iron ion (the ferricenium ion). Thus, a possible explanation for this PDH multiplicity in A. meleagris could be that different isoforms react preferentially with structurally different electron acceptors in vivo.
[Mh] Termos MeSH primário: Agaricus/enzimologia
Desidrogenases de Carboidrato/química
Desidrogenases de Carboidrato/metabolismo
Celulose/metabolismo
Isoenzimas/química
Isoenzimas/metabolismo
[Mh] Termos MeSH secundário: Agaricus/genética
Agaricus/metabolismo
Desidrogenases de Carboidrato/genética
Desidrogenases de Carboidrato/isolamento & purificação
Domínio Catalítico/genética
Proteínas Fúngicas/genética
Galactose/metabolismo
Glucose/metabolismo
Concentração de Íons de Hidrogênio
Isoenzimas/genética
Isoenzimas/isolamento & purificação
Cinética
Família Multigênica/genética
Oxirredução
Especificidade por Substrato
Xilose/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fungal Proteins); 0 (Isoenzymes); 9004-34-6 (Cellulose); A1TA934AKO (Xylose); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.3.10 (pyranose oxidase); IY9XDZ35W2 (Glucose); X2RN3Q8DNE (Galactose)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170405
[Lr] Data última revisão:
170405
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161221
[St] Status:MEDLINE
[do] DOI:10.1007/s00253-016-8051-1


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[PMID]:27851982
[Au] Autor:Kadek A; Kavan D; Marcoux J; Stojko J; Felice AK; Cianférani S; Ludwig R; Halada P; Man P
[Ad] Endereço:BioCeV - Institute of Microbiology, The Czech Academy of Sciences, Prumyslova 595, 252 50 Vestec, Czech Republic; Department of Biochemistry, Faculty of Science, Charles University in Prague, Hlavova 8, 128 43 Prague, Czech Republic.
[Ti] Título:Interdomain electron transfer in cellobiose dehydrogenase is governed by surface electrostatics.
[So] Source:Biochim Biophys Acta;1861(2):157-167, 2017 02.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Cellobiose dehydrogenase (CDH) is a fungal extracellular oxidoreductase which fuels lytic polysaccharide monooxygenase with electrons during cellulose degradation. Interdomain electron transfer between the flavin and cytochrome domain in CDH, preceding the electron flow to lytic polysaccharide monooxygenase, is known to be pH dependent, but the exact mechanism of this regulation has not been experimentally proven so far. METHODS: To investigate the structural aspects underlying the domain interaction in CDH, hydrogen/deuterium exchange (HDX-MS) with improved proteolytic setup (combination of nepenthesin-1 with rhizopuspepsin), native mass spectrometry with ion mobility and electrostatics calculations were used. RESULTS: HDX-MS revealed pH-dependent changes in solvent accessibility and hydrogen bonding at the interdomain interface. Electrostatics calculations identified these differences to result from charge neutralization by protonation and together with ion mobility pointed at higher electrostatic repulsion between CDH domains at neutral pH. In addition, we uncovered extensive O-glycosylation in the linker region and identified the long-unknown exact cleavage point in papain-mediated domain separation. CONCLUSIONS: Transition of CDH between its inactive (open) and interdomain electron transfer-capable (closed) state is shown to be governed by changes in the protein surface electrostatics at the domain interface. Our study confirms that the interdomain electrostatic repulsion is the key factor modulating the functioning of CDH. GENERAL SIGNIFICANCE: The results presented in this paper provide experimental evidence for the role of charge repulsion in the interdomain electron transfer in cellobiose dehydrogenases, which is relevant for exploiting their biotechnological potential in biosensors and biofuel cells.
[Mh] Termos MeSH primário: Desidrogenases de Carboidrato/metabolismo
Celobiose/metabolismo
Transporte de Elétrons/fisiologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Citocromos/metabolismo
Deutério/metabolismo
Elétrons
Flavinas/metabolismo
Proteínas Fúngicas/metabolismo
Fungos/metabolismo
Glicosilação
Hidrogênio/metabolismo
Concentração de Íons de Hidrogênio
Oxigenases de Função Mista/metabolismo
Polissacarídeos/metabolismo
Domínios Proteicos
Proteólise
Eletricidade Estática
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Cytochromes); 0 (Flavins); 0 (Fungal Proteins); 0 (Polysaccharides); 16462-44-5 (Cellobiose); 7YNJ3PO35Z (Hydrogen); AR09D82C7G (Deuterium); EC 1.- (Mixed Function Oxygenases); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.99.18 (cellobiose-quinone oxidoreductase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161117
[St] Status:MEDLINE



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