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Pesquisa : D08.811.913.400.450.460.100 [Categoria DeCS]
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[PMID]:28757093
[Au] Autor:Wychowski A; Bompard C; Grimaud F; Potocki-Véronèse G; D'Hulst C; Wattebled F; Roussel X
[Ad] Endereço:Univ. Lille, CNRS, UMR8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille, France.
[Ti] Título:Biochemical characterization of Arabidopsis thaliana starch branching enzyme 2.2 reveals an enzymatic positive cooperativity.
[So] Source:Biochimie;140:146-158, 2017 Sep.
[Is] ISSN:1638-6183
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:Starch Branching Enzymes (SBE) catalyze the formation of α(1 â†’ 6) branching points on starch polymers: amylopectin and amylose. SBEs are classified in two groups named type 1 and 2. Both types are present in the entire plant kingdom except in some species such as Arabidopsis thaliana that expresses two type 2 SBEs: BE2.1 and BE2.2. The present work describes in vitro enzymatic characterization of the recombinant BE2.2. The function of recombinant BE2.2 was characterized in vitro using spectrophotometry assay, native PAGE and HPAEC-PAD analysis. Size Exclusion Chromatography separation and SAXS experiments were used to identify the oligomeric state and for structural analysis of this enzyme. Optimal pH and temperature for BE2.2 activity were determined to be pH 7 and 25 °C. A glucosyl donor of at least 12 residues is required for BE2.2 activity. The reaction results in the transfer in an α(1 â†’ 6) position of a glucan preferentially composed of 6 glucosyl units. In addition, BE2.2, which has been shown to be monomeric in absence of substrate, is able to adopt different active forms in presence of branched substrates, which affect the kinetic parameters. BE2.2 has substrate specificity similar to those of the other type-2 BEs. We propose that the different conformations of the enzyme displaying more or less affinity toward its substrates would explain the adjustment of the kinetic data to the Hill equation. This work describes the enzymatic parameters of Arabidopsis BE2.2. It reveals for the first time conformational changes for a branching enzyme, leading to a positive cooperative binding process of this enzyme.
[Mh] Termos MeSH primário: Enzima Ramificadora de 1,4-alfa-Glucana
Proteínas de Arabidopsis
Arabidopsis
[Mh] Termos MeSH secundário: Enzima Ramificadora de 1,4-alfa-Glucana/biossíntese
Enzima Ramificadora de 1,4-alfa-Glucana/química
Enzima Ramificadora de 1,4-alfa-Glucana/genética
Enzima Ramificadora de 1,4-alfa-Glucana/isolamento & purificação
Arabidopsis/enzimologia
Arabidopsis/genética
Proteínas de Arabidopsis/biossíntese
Proteínas de Arabidopsis/química
Proteínas de Arabidopsis/genética
Proteínas de Arabidopsis/isolamento & purificação
Proteínas Recombinantes/biossíntese
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Arabidopsis Proteins); 0 (Recombinant Proteins); EC 2.4.1.18 (1,4-alpha-Glucan Branching Enzyme)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170915
[Lr] Data última revisão:
170915
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170801
[St] Status:MEDLINE


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[PMID]:28557456
[Au] Autor:Liu Y; Ban X; Li C; Gu Z; Cheng L; Hong Y; Li Z
[Ad] Endereço:School of Food Science and Technology, Jiangnan University , Wuxi 214122, China.
[Ti] Título:Met349 Mutations Enhance the Activity of 1,4-α-Glucan Branching Enzyme from Geobacillus thermoglucosidans STB02.
[So] Source:J Agric Food Chem;65(28):5674-5680, 2017 Jul 19.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:1,4-α-Glucan branching enzyme (GBE, EC 2.4.1.18) is used to increase the number of α-1,6 branch points in starch and glycogen. On the basis of a multiple sequence alignment of the GBEs from a variety of bacteria, residue 349 (Geobacillus thermoglucosidans STB02 numbering) in region III is generally methionine in bacteria with higher identity, while it is threonine or serine in bacteria with lower identity. Four mutants (M349T, M349S, M349H, and M349Y) were constructed by site-directed mutagenesis and characterized. M349T and M349S showed 24.5% and 21.1% increases in specific activity compared with that of wild-type GBE, respectively. In addition, M349T and M349S displayed 24.2% and 17.6% enhancements in the α-1,6-glycosidic linkage ratio of potato starch samples, respectively. However, M349Y displayed a significant reduction in activity. Moreover, the mutations at M349 have a negligible effect on substrate specificity. Thus, M349T and M349S are more suitable for industrial applications than wild-type GBE.
[Mh] Termos MeSH primário: Enzima Ramificadora de 1,4-alfa-Glucana/genética
Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Geobacillus/enzimologia
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Geobacillus/química
Geobacillus/genética
Glicogênio/metabolismo
Mutagênese Sítio-Dirigida
Mutação
Mutação de Sentido Incorreto
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 9005-79-2 (Glycogen); EC 2.4.1.18 (1,4-alpha-Glucan Branching Enzyme)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170728
[Lr] Data última revisão:
170728
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170531
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b01227


  3 / 427 MEDLINE  
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[PMID]:28163025
[Au] Autor:Na S; Park M; Jo I; Cha J; Ha NC
[Ad] Endereço:Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea.
[Ti] Título:Structural basis for the transglycosylase activity of a GH57-type glycogen branching enzyme from Pyrococcus horikoshii.
[So] Source:Biochem Biophys Res Commun;484(4):850-856, 2017 Mar 18.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Glycogen branching enzyme (GBE) catalyzes the formation of α-1,6-branching points during glycogenesis by cleaving α-1,4 bonds and making new α-1,6 bonds. Most GBEs belong to the glycoside hydrolase 13 family (GH13), but new GBEs in the GH57 family have been isolated from Archaea. Here, we determined the crystal structure of a GH57 GBE from the hyperthermophilic archaeon Pyrococcus horikoshii (PhGBE) at a resolution of 2.3 Å. PhGBE exhibits both α-1,6-branching activity and endo-α-1,4 hydrolytic activity. PhGBE has a central (ß/α) -barrel domain that contains an embedded helix domain and an α-helix-rich C-terminal domain. The active-site cleft is located at the interface of the central and C-terminal domains. Amino acid substitution at Trp22, which is separate from the catalytic nucleophilic residue, abolished both enzymatic activities, indicating that Trp22 might be responsible for substrate recognition. We also observed that shortening of the flexible loop near the catalytic residue changed branched chain lengths of the reaction products with increased hydrolytic activity. Taken together, our findings propose a molecular mechanism for how GH57 GBEs exhibit the two activities and where the substrate binds the enzyme.
[Mh] Termos MeSH primário: Enzima Ramificadora de 1,4-alfa-Glucana/química
Enzima Ramificadora de 1,4-alfa-Glucana/ultraestrutura
Glicogênio/química
Peptidoglicano Glicosiltransferase/química
Peptidoglicano Glicosiltransferase/ultraestrutura
Pyrococcus horikoshii/enzimologia
[Mh] Termos MeSH secundário: Sítios de Ligação
Ativação Enzimática
Ligação Proteica
Conformação Proteica
Relação Estrutura-Atividade
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9005-79-2 (Glycogen); EC 2.4.1.129 (Peptidoglycan Glycosyltransferase); EC 2.4.1.18 (1,4-alpha-Glucan Branching Enzyme)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:171120
[Lr] Data última revisão:
171120
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170207
[St] Status:MEDLINE


  4 / 427 MEDLINE  
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[PMID]:28122205
[Au] Autor:Ren J; Li Y; Li C; Gu Z; Cheng L; Hong Y; Li Z
[Ad] Endereço:School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
[Ti] Título:Pasting and thermal properties of waxy corn starch modified by 1,4-α-glucan branching enzyme.
[So] Source:Int J Biol Macromol;97:679-687, 2017 Apr.
[Is] ISSN:1879-0003
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Waxy corn starch was modified with the 1,4-α-glucan branching enzyme (GBE) from Geobacillus thermoglucosidans STB02. Incubating waxy corn starch with GBE increased the number of α-1,6 branch points and reduced the average chain length. Enzymatic modification also decreased the breakdown and setback values of Brabender viscosity curves, indicating that the modified starch had higher paste stability. Preheating the starch at 65°C for 30min before incubation with GBE could promote enzymatic modification of starch. Linear regression was used to describe the relationships between starch structure and its pasting and thermal properties. The setback value showed a negative linear correlation with the α-1,6 branch point content (R =0.9824) and a positive linear correlation with the average chain length (R =0.8954). Meanwhile, the gelatinization enthalpy was also linearly correlated to the α-1,6 branch point content (R =0.9326) and the average chain length (R =0.8567). These insights provide a useful reference for food processors.
[Mh] Termos MeSH primário: Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo
Amido/química
Temperatura Ambiente
Ceras/química
Zea mays/química
[Mh] Termos MeSH secundário: Geobacillus/enzimologia
Glicosídeos/química
Pomadas
Amido/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Glycosides); 0 (Ointments); 0 (Waxes); 9005-25-8 (Starch); EC 2.4.1.18 (1,4-alpha-Glucan Branching Enzyme)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170421
[Lr] Data última revisão:
170421
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170126
[St] Status:MEDLINE


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[PMID]:28082221
[Au] Autor:Liu Y; Li C; Gu Z; Xin C; Cheng L; Hong Y; Li Z
[Ad] Endereço:School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
[Ti] Título:Alanine 310 is important for the activity of 1,4-α-glucan branching enzyme from Geobacillus thermoglucosidans STB02.
[So] Source:Int J Biol Macromol;97:156-163, 2017 Apr.
[Is] ISSN:1879-0003
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:1,4-α-Glucan branching enzyme (GBE) catalyzes the formation of α-1,6 branch points in starch or glycogen by hydrolyzing α-1,4-glucosidic linkages and then synthesizing α-1,6-glucosidic linkages. In the GBE from Geobacillus thermoglucosidans STB02, alanine 310 (Ala310) is located in conserved region II. An analysis of the amino acid sequence shows that Ala310 is highly conserved in the prokaryotic GBE subfamily. Site-directed mutagenesis was used to determine the function of Ala310 in GBE. Replacement of Ala310 with glycine, aspartate, asparagine, isoleucine, glutamate, or glutamine resulted in mutant enzymes with less than 10% to 25% of wild-type activity when amylopectin or amylose was used as substrate. Studies using high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) showed that A310G mutant had no effect on the transfer pattern, but the branching activity had been repressed to a large extent. Kinetic analysis also showed that mutations of Ala310 had an effect on the K value that changed the preferred substrate from amylopectin to amylose. These results show that Ala310 is important for the catalytic activity of the GBE from G. thermoglucosidans STB02.
[Mh] Termos MeSH primário: Enzima Ramificadora de 1,4-alfa-Glucana/química
Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo
Alanina
Geobacillus/enzimologia
Mutagênese Sítio-Dirigida
[Mh] Termos MeSH secundário: Enzima Ramificadora de 1,4-alfa-Glucana/genética
Biocatálise
Modelos Moleculares
Mutação
Conformação Proteica
Análise de Sequência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
EC 2.4.1.18 (1,4-alpha-Glucan Branching Enzyme); OF5P57N2ZX (Alanine)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170410
[Lr] Data última revisão:
170410
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170114
[St] Status:MEDLINE


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[PMID]:27855897
[Au] Autor:Xu J; Kuang Q; Wang K; Zhou S; Wang S; Liu X; Wang S
[Ad] Endereço:Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science & Technology, Tianjin 300457, China; Institute of Food Science and Technology (IFST), Chinese Academy of Agricultural Science (CAAS), Beijing 100193, China.
[Ti] Título:Insights into molecular structure and digestion rate of oat starch.
[So] Source:Food Chem;220:25-30, 2017 Apr 01.
[Is] ISSN:0308-8146
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The in vitro digestibility of oat starch and its relationship with starch molecular structure was investigated. The in vitro digestion results showed that the first-order kinetic constant (k) of oat starches (OS-1 and OS-2) was lower than that of rice starch. The size of amylose chains, amylose content and degree of branching (DB) of amylopectin in oat starch were significantly higher than the corresponding parameters in rice starch. The larger molecular size of oat starch may account for its lower digestion rate. The fine structure of amylopectin showed that oat starch had less chains of DP 6-12 and DP>36, which may explain the small difference in digestion rate between oat and rice starch. The biosynthesis model from oat amylopectin fine structure data suggested a lower starch branching enzyme (SBE) activity and/or a higher starch synthase (SS) activity, which may decrease the DB of oat starch and increase its digestion rate.
[Mh] Termos MeSH primário: Amilose/química
Avena/química
Amido/química
[Mh] Termos MeSH secundário: Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo
Amilopectina/química
Cinética
Estrutura Molecular
Oryza/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9005-25-8 (Starch); 9005-82-7 (Amylose); 9037-22-3 (Amylopectin); EC 2.4.1.18 (1,4-alpha-Glucan Branching Enzyme)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:161231
[Lr] Data última revisão:
161231
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161119
[St] Status:MEDLINE


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[PMID]:27832700
[Au] Autor:Yi H; Zhang Q; Brooks ED; Yang C; Thurberg BL; Kishnani PS; Sun B
[Ad] Endereço:1 Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center , Durham, North Carolina.
[Ti] Título:Systemic Correction of Murine Glycogen Storage Disease Type IV by an AAV-Mediated Gene Therapy.
[So] Source:Hum Gene Ther;28(3):286-294, 2017 Mar.
[Is] ISSN:1557-7422
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Deficiency of glycogen branching enzyme (GBE) causes glycogen storage disease type IV (GSD IV), which is characterized by the accumulation of a less branched, poorly soluble form of glycogen called polyglucosan (PG) in multiple tissues. This study evaluates the efficacy of gene therapy with an adeno-associated viral (AAV) vector in a mouse model of adult form of GSD IV (Gbe1 ). An AAV serotype 9 (AAV9) vector containing a human GBE expression cassette (AAV-GBE) was intravenously injected into 14-day-old Gbe1 mice at a dose of 5 × 10 vector genomes per mouse. Mice were euthanized at 3 and 9 months of age. In the AAV-treated mice at 3 months of age, GBE enzyme activity was highly elevated in heart, which is consistent with the high copy number of the viral vector genome detected. GBE activity also increased significantly in skeletal muscles and the brain, but not in the liver. The glycogen content was reduced to wild-type levels in muscles and significantly reduced in the liver and brain. At 9 months of age, though GBE activity was only significantly elevated in the heart, glycogen levels were significantly reduced in the liver, brain, and skeletal muscles of the AAV-treated mice. In addition, the AAV treatment resulted in an overall decrease in plasma activities of alanine transaminase, aspartate transaminase, and creatine kinase, and a significant increase in fasting plasma glucose concentration at 9 months of age. This suggests an alleviation of damage and improvement of function in the liver and muscles by the AAV treatment. This study demonstrated a long-term benefit of a systemic injection of an AAV-GBE vector in Gbe1 mice.
[Mh] Termos MeSH primário: Enzima Ramificadora de 1,4-alfa-Glucana/genética
Dependovirus/genética
Terapia Genética
Vetores Genéticos/administração & dosagem
Doença de Depósito de Glicogênio Tipo IV/terapia
Glicogênio/metabolismo
[Mh] Termos MeSH secundário: Animais
Modelos Animais de Doenças
Doença de Depósito de Glicogênio Tipo IV/genética
Seres Humanos
Fígado/metabolismo
Masculino
Camundongos
Camundongos Endogâmicos C57BL
Músculo Esquelético/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9005-79-2 (Glycogen); EC 2.4.1.18 (1,4-alpha-Glucan Branching Enzyme)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170912
[Lr] Data última revisão:
170912
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161112
[St] Status:MEDLINE
[do] DOI:10.1089/hum.2016.099


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[PMID]:27416069
[Au] Autor:Ban X; Li C; Gu Z; Bao C; Qiu Y; Hong Y; Cheng L; Li Z
[Ad] Endereço:State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.
[Ti] Título:Expression and Biochemical Characterization of a Thermostable Branching Enzyme from Geobacillus thermoglucosidans.
[So] Source:J Mol Microbiol Biotechnol;26(5):303-11, 2016.
[Is] ISSN:1660-2412
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:The branching enzyme (EC 2.4.1.18) catalyzes the formation of α-1,6 branch points in starch. In this study, the Geobacillus thermoglucosidans gene-encoding branching enzyme was expressed in Escherichia coli BL21 (DE3) and the protein was isolated and characterized. G. thermoglucosidans branching enzyme is a thermostable enzyme with an optimal reaction temperature of nearly 60°C and a half-life at 65°C of approximately 1.1 h. The activity of the recombinant enzyme is optimal at pH 7.5, with broad stability between pH 5.5 and 9.0. Its thermostability, relatively broad pH stability and optimal temperature near the temperature at which starch begins to gelatinize may make it easy to use in industrial production. Furthermore, the enzyme is activated by Mg2+, Ba2+, K+ and Na+ in a concentration-dependent manner and dramatically inhibited by Ni2+ and Co2+. Its substrate dependence, using amylopectin as the substrate, could be adequately fitted using the Michaelis-Menten equation, yielding a Km of 0.99 mg/ml. High-performance anion exchange chromatography results showed that the chain length distribution of branching enzyme-treated waxy corn starch is indistinguishable from that of the branching enzyme-treated common corn starch. This enzyme may therefore be a promising tool for the enzymatic modification of starch.
[Mh] Termos MeSH primário: Enzima Ramificadora de 1,4-alfa-Glucana/isolamento & purificação
Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo
Geobacillus/enzimologia
Amido/metabolismo
[Mh] Termos MeSH secundário: Enzima Ramificadora de 1,4-alfa-Glucana/química
Enzima Ramificadora de 1,4-alfa-Glucana/genética
Clonagem Molecular
Ativadores de Enzimas
Inibidores Enzimáticos
Estabilidade Enzimática
Escherichia coli/genética
Escherichia coli/metabolismo
Expressão Gênica
Geobacillus/genética
Concentração de Íons de Hidrogênio
Íons
Cinética
Metais
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/isolamento & purificação
Proteínas Recombinantes/metabolismo
Temperatura Ambiente
Zea mays/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Enzyme Activators); 0 (Enzyme Inhibitors); 0 (Ions); 0 (Metals); 0 (Recombinant Proteins); 9005-25-8 (Starch); EC 2.4.1.18 (1,4-alpha-Glucan Branching Enzyme)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170508
[Lr] Data última revisão:
170508
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160715
[St] Status:MEDLINE
[do] DOI:10.1159/000446582


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[PMID]:27139627
[Au] Autor:Feng L; Fawaz R; Hovde S; Sheng F; Nosrati M; Geiger JH
[Ad] Endereço:Department of Chemistry, Michigan State University, 578 South Shaw Lane, East Lansing, MI 48824, USA.
[Ti] Título:Crystal structures of Escherichia coli branching enzyme in complex with cyclodextrins.
[So] Source:Acta Crystallogr D Struct Biol;72(Pt 5):641-7, 2016 05.
[Is] ISSN:2059-7983
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Branching enzyme (BE) is responsible for the third step in glycogen/starch biosynthesis. It catalyzes the cleavage of α-1,4 glucan linkages and subsequent reattachment to form α-1,6 branch points. These branches are crucial to the final structure of glycogen and starch. The crystal structures of Escherichia coli BE (EcBE) in complex with α-, ß- and γ-cyclodextrin were determined in order to better understand substrate binding. Four cyclodextrin-binding sites were identified in EcBE; they were all located on the surface of the enzyme, with none in the vicinity of the active site. While three of the sites were also identified as linear polysaccharide-binding sites, one of the sites is specific for cyclodextrins. In previous work three additional binding sites were identified as exclusively binding linear malto-oligosaccharides. Comparison of the binding sites shed light on this apparent specificity. Binding site IV is located in the carbohydrate-binding module 48 (CBM48) domain of EcBE and superimposes with the cyclodextrin-binding site found in the CBM48 domain of 5'-AMP-activated protein kinase (AMPK). Comparison of these sites shows the similarities and differences in the two binding modes. While some of the binding sites were found to be conserved between branching enzymes of different organisms, some are quite divergent, indicating both similarities and differences between oligosaccharide binding in branching enzymes from various sources.
[Mh] Termos MeSH primário: Enzima Ramificadora de 1,4-alfa-Glucana/química
Ciclodextrinas/química
Escherichia coli/química
Escherichia coli/enzimologia
[Mh] Termos MeSH secundário: Sítios de Ligação
Cristalografia por Raios X/métodos
Glicogênio/química
Modelos Moleculares
Conformação Proteica
Domínios Proteicos
Amido/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Cyclodextrins); 9005-25-8 (Starch); 9005-79-2 (Glycogen); EC 2.4.1.18 (1,4-alpha-Glucan Branching Enzyme)
[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:160504
[St] Status:MEDLINE
[do] DOI:10.1107/S2059798316003272


  10 / 427 MEDLINE  
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[PMID]:27083356
[Au] Autor:Jo AR; Kim HR; Choi SJ; Lee JS; Chung MN; Han SK; Park CS; Moon TW
[Ad] Endereço:Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea.
[Ti] Título:Preparation of slowly digestible sweet potato Daeyumi starch by dual enzyme modification.
[So] Source:Carbohydr Polym;143:164-71, 2016 Jun 05.
[Is] ISSN:1879-1344
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Sweet potato Daeyumi starch was dually modified using glycogen branching enzyme (BE) from Streptococcus mutans and amylosucrase (AS) from Neisseria polysaccharea to prepare slowly digestible starch (SDS). Dually modified starches had higher SDS and resistant starch (RS) contents than control starch. The branched chain length distributions of the BE-modified starches indicated an increase in short side-chains [degree of polymerization (DP)≤12] compared with native starch. AS treatment of the BE-modified starches decreased the proportion of short side-chains and increased the proportion of long side-chains (DP≥25) and molecular mass. It also resulted in a B-type X-ray diffraction pattern and an increased relative crystallinity. Regarding thermal properties, the BE-modified starches showed no endothermic peak, whereas the BEAS-modified starches had a broader melting temperature range and lower melting enthalpy compared to native starch. The combined enzymatic treatment resulted in novel glucan polymers with slow digestion properties.
[Mh] Termos MeSH primário: Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo
Amilopectina/metabolismo
Glucosiltransferases/metabolismo
Ipomoea batatas/química
[Mh] Termos MeSH secundário: Amilopectina/química
Amilopectina/isolamento & purificação
Animais
Digestão
Neisseria
Pancreatina/metabolismo
Streptococcus mutans
Suínos
Temperatura Ambiente
Termodinâmica
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
8049-47-6 (Pancreatin); 9037-22-3 (Amylopectin); EC 2.4.1.- (Glucosyltransferases); EC 2.4.1.18 (1,4-alpha-Glucan Branching Enzyme); EC 2.4.1.4 (amylosucrase)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170213
[Lr] Data última revisão:
170213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160417
[St] Status:MEDLINE



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