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  1 / 446 MEDLINE  
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[PMID]:27904965
[Au] Autor:Shahid F; Aman A; Nawaz MA; Karim A; Ul Qader SA
[Ad] Endereço:The Karachi Institute of Biotechnology and Genetic Engineering (KIBGE), University of Karachi, Karachi, 75270, Pakistan.
[Ti] Título:Chitosan hydrogel microspheres: an effective covalent matrix for crosslinking of soluble dextranase to increase stability and recycling efficiency.
[So] Source:Bioprocess Biosyst Eng;40(3):451-461, 2017 Mar.
[Is] ISSN:1615-7605
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Dextranase is a unique biocatalyst that has high specificity and stereo-selectivity towards a complex biopolymer known as dextran. Dextranase has wide industrial application, but most of the time harsh environmental conditions adversely affect the functionality and stability of the enzyme. To overcome this issue, a covalent cross-linking immobilization method was adapted in the current study utilizing a nontoxic and biocompatible matrix known as chitosan. Chitosan hydrogel microspheres were synthesized using chitosan which exhibited noteworthy physical and mechanical strength. After treatment with glutaraldehyde, chitosan hydrogel microspheres were used for immobilization of dextranase. The kinetic characteristics of immobilized dextranase were compared with that of the soluble enzyme. A shift in optimum pH and temperature from 7.0 to 7.5 and 50 to 60 °C was observed after immobilization, respectively. Recycling efficiency, thermal stability, and activation energy distinctly improved after immobilization, whereas anchoring of substrate at the active site of the soluble dextranase exhibited an increase in K with no change in V after crosslinking. This technique involves the reduction in the size of carrier molecules (microspheres) that provide a larger surface area for improved immobilization efficiency. Therefore, it is concluded that increased stability and reusability of this immobilized biocatalyst makes it a promising aspirant for the utilization at commercial level.
[Mh] Termos MeSH primário: Bacillus megaterium/metabolismo
Quitosana/química
Enzimas Imobilizadas/química
Microesferas
[Mh] Termos MeSH secundário: Reagentes para Ligações Cruzadas/química
Dextranase/química
Estabilidade Enzimática
Enzimas/química
Glutaral/química
Temperatura Alta
Hidrogéis/química
Concentração de Íons de Hidrogênio
Microbiologia Industrial
Cinética
Reprodutibilidade dos Testes
Especificidade por Substrato
Propriedades de Superfície
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cross-Linking Reagents); 0 (Enzymes); 0 (Enzymes, Immobilized); 0 (Hydrogels); 9012-76-4 (Chitosan); EC 3.2.1.11 (Dextranase); T3C89M417N (Glutaral)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170317
[Lr] Data última revisão:
170317
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161202
[St] Status:MEDLINE
[do] DOI:10.1007/s00449-016-1713-7


  2 / 446 MEDLINE  
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[PMID]:26969579
[Au] Autor:Pleszczynska M; Wiater A; Bachanek T; Szczodrak J
[Ad] Endereço:Department of Industrial Microbiology, Maria Curie-Sklodowska University, Lublin, Poland.
[Ti] Título:Enzymes in therapy of biofilm-related oral diseases.
[So] Source:Biotechnol Appl Biochem;64(3):337-346, 2017 May.
[Is] ISSN:1470-8744
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Biofilm-related infections of the oral cavity, including dental caries and periodontitis, represent the most prevalent health problems. For years, the treatment thereof was largely based on antibacterial chemical agents. Recently, however, there has been growing interest in the application of more preventive and minimally invasive biotechnological methods. This review focuses on the potential applications of enzymes in the treatment and prevention of oral diseases. Dental plaque is a microbial community that develops on the tooth surface, embedded in a matrix of extracellular polymeric substances of bacterial and host origin. Both cariogenic microorganisms and the key components of oral biofilm matrix may be the targets of the enzymes. Oxidative salivary enzymes inhibit or limit the growth of oral pathogens, thereby supporting the natural host defense system; polysaccharide hydrolases (mutanases and dextranases) degrade important carbohydrate components of the biofilm matrix, whereas proteases disrupt bacterial adhesion to oral surfaces or affect cell-cell interactions. The efficiency of the enzymes in in vitro and in vivo studies, advantages and limitations, as well as future perspectives for improving the enzymatic strategy are discussed.
[Mh] Termos MeSH primário: Antibacterianos/uso terapêutico
Bactérias/crescimento & desenvolvimento
Aderência Bacteriana/efeitos dos fármacos
Biofilmes/crescimento & desenvolvimento
Dextranase/uso terapêutico
Glicosídeo Hidrolases/uso terapêutico
Periodontite
[Mh] Termos MeSH secundário: Placa Dentária/tratamento farmacológico
Placa Dentária/microbiologia
Seres Humanos
Periodontite/tratamento farmacológico
Periodontite/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); EC 3.2.1.- (Glycoside Hydrolases); EC 3.2.1.11 (Dextranase); EC 3.2.1.84 (exo-1,3-alpha-glucanase)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170626
[Lr] Data última revisão:
170626
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160313
[St] Status:MEDLINE
[do] DOI:10.1002/bab.1490


  3 / 446 MEDLINE  
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[PMID]:27762637
[Au] Autor:Wang X; Cheng H; Lu M; Fang Y; Jiao Y; Li W; Zhao G; Wang S
[Ad] Endereço:a Marine Resources Development Institute of Jiangsu , Lianyungang , PR China.
[Ti] Título:Dextranase from Arthrobacter oxydans KQ11-1 inhibits biofilm formation by polysaccharide hydrolysis.
[So] Source:Biofouling;32(10):1223-1233, 2016 Nov.
[Is] ISSN:1029-2454
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Dental plaque is a biofilm of water-soluble and water-insoluble polysaccharides, produced primarily by Streptococcus mutans. Dextranase can inhibit biofilm formation. Here, a dextranase gene from the marine microorganism Arthrobacter oxydans KQ11-1 is described, and cloned and expressed using E. coli DH5α competent cells. The recombinant enzyme was then purified and its properties were characterized. The optimal temperature and pH were determined to be 60°C and 6.5, respectively. High-performance liquid chromatography data show that the final hydrolysis products were glucose, maltose, maltotriose, and maltotetraose. Thus, dextranase can inhibit the adhesive ability of S. mutans. The minimum biofilm inhibition and reduction concentrations (MBIC and MBRC ) of dextranase were 2 U ml and 5 U ml , respectively. Scanning electron microscopy and confocal laser scanning microscope (CLSM) observations confirmed that dextranase inhibited biofilm formation and removed previously formed biofilms.
[Mh] Termos MeSH primário: Arthrobacter/enzimologia
Biofilmes/efeitos dos fármacos
Placa Dentária/prevenção & controle
Dextranase/farmacologia
Polissacarídeos/química
Streptococcus mutans/fisiologia
[Mh] Termos MeSH secundário: Aderência Bacteriana/efeitos dos fármacos
Placa Dentária/microbiologia
Dextranase/química
Dextranase/genética
Escherichia coli/efeitos dos fármacos
Hidrólise
Proteínas Recombinantes
Streptococcus mutans/efeitos dos fármacos
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Polysaccharides); 0 (Recombinant Proteins); EC 3.2.1.11 (Dextranase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170816
[Lr] Data última revisão:
170816
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161021
[St] Status:MEDLINE


  4 / 446 MEDLINE  
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[PMID]:27170214
[Au] Autor:Gozu Y; Ishizaki Y; Hosoyama Y; Miyazaki T; Nishikawa A; Tonozuka T
[Ad] Endereço:a Department of Applied Biological Science , Tokyo University of Agriculture and Technology , Fuchu , Japan.
[Ti] Título:A glycoside hydrolase family 31 dextranase with high transglucosylation activity from Flavobacterium johnsoniae.
[So] Source:Biosci Biotechnol Biochem;80(8):1562-7, 2016 Aug.
[Is] ISSN:1347-6947
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Glycoside hydrolase family (GH) 31 enzymes exhibit various substrate specificities, although the majority of members are α-glucosidases. Here, we constructed a heterologous expression system of a GH31 enzyme, Fjoh_4430, from Flavobacterium johnsoniae NBRC 14942, using Escherichia coli, and characterized its enzymatic properties. The enzyme hydrolyzed dextran and pullulan to produce isomaltooligosaccharides and isopanose, respectively. When isomaltose was used as a substrate, the enzyme catalyzed disproportionation to form isomaltooligosaccharides. The enzyme also acted, albeit inefficiently, on p-nitrophenyl α-D-glucopyranoside, and p-nitrophenyl α-isomaltoside was the main product of the reaction. In contrast, Fjoh_4430 did not act on trehalose, kojibiose, nigerose, maltose, maltotriose, or soluble starch. The optimal pH and temperature were pH 6.0 and 60 °C, respectively. Our results indicate that Fjoh_4430 is a novel GH31 dextranase with high transglucosylation activity.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Dextranase/metabolismo
Dextranos/metabolismo
Escherichia coli/enzimologia
Flavobacterium/enzimologia
Glucosiltransferases/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Dextranase/genética
Dextranos/química
Escherichia coli/genética
Flavobacterium/genética
Glucanos/química
Glucanos/metabolismo
Glucosiltransferases/genética
Concentração de Íons de Hidrogênio
Hidrólise
Isomaltose/química
Isomaltose/metabolismo
Oligossacarídeos/química
Oligossacarídeos/metabolismo
Engenharia de Proteínas
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Especificidade por Substrato
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Dextrans); 0 (Glucans); 0 (Oligosaccharides); 0 (Recombinant Proteins); 0 (maltooligosaccharides); 67I334IX2M (Isomaltose); 8ZQ0AYU1TT (pullulan); EC 2.4.1.- (Glucosyltransferases); EC 3.2.1.11 (Dextranase)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170118
[Lr] Data última revisão:
170118
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160513
[St] Status:MEDLINE
[do] DOI:10.1080/09168451.2016.1182852


  5 / 446 MEDLINE  
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[PMID]:27130366
[Au] Autor:LeClair DA; Cranston ED; Xing Z; Thompson MR
[Ad] Endereço:Department of Chemical Engineering, McMaster University, Hamilton, Ontario L8S 4L7, Canada.
[Ti] Título:Evaluation of excipients for enhanced thermal stabilization of a human type 5 adenoviral vector through spray drying.
[So] Source:Int J Pharm;506(1-2):289-301, 2016 Jun 15.
[Is] ISSN:1873-3476
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:We have produced a thermally stable recombinant human type 5 adenoviral vector (AdHu5) through spray drying with three excipient formulations (l-leucine, lactose/trehalose and mannitol/dextran). Spray drying leads to immobilization of the viral vector which is believed to prevent viral protein unfolding, aggregation and inactivation. The spray dried powders were characterized by scanning electron microscopy, differential scanning calorimetry, Karl Fischer titrations, and X-ray diffraction to identify the effects of temperature and atmospheric moisture on the immobilizing matrix. Thermal stability of the viral vector was confirmed in vitro by infection of A549 lung epithelial cells. Mannitol/dextran powders showed the greatest improvement in thermal stability with almost no viral activity loss after storage at 20°C for 90days (0.7±0.3 log TCID50) which is a significant improvement over the current -80°C storage protocol. Furthermore, viral activity was retained over short term exposure (72h) to temperatures as high as 55°C. Conversely, all powders exhibited activity loss when subjected to moisture due to amplified molecular motion of the matrix. Overall, a straightforward method ideal for the production of thermally stable vaccines has been demonstrated through spray drying AdHu5 with a blend of mannitol and dextran and storing the powder under low humidity conditions.
[Mh] Termos MeSH primário: Adenovírus Humanos/genética
Excipientes/química
Vetores Genéticos/administração & dosagem
[Mh] Termos MeSH secundário: Células A549
Varredura Diferencial de Calorimetria
Dextranase
Vetores Genéticos/química
Seres Humanos
Umidade
Lactose/química
Leucina/química
Manitol/química
Microscopia Eletrônica de Varredura
Pós
Temperatura Ambiente
Fatores de Tempo
Trealose/química
Difração de Raios X
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Excipients); 0 (Powders); 3OWL53L36A (Mannitol); B8WCK70T7I (Trehalose); EC 3.2.1.11 (Dextranase); GMW67QNF9C (Leucine); J2B2A4N98G (Lactose)
[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:160501
[St] Status:MEDLINE


  6 / 446 MEDLINE  
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[PMID]:26907761
[Au] Autor:Ko JA; Nam SH; Kim D; Lee JH; Kim YM
[Ad] Endereço:Eco-Friendly Bio-material Research Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea.
[Ti] Título:Identification of Catalytic Amino Acid Residues by Chemical Modification in Dextranase.
[So] Source:J Microbiol Biotechnol;26(5):837-45, 2016 May 28.
[Is] ISSN:1738-8872
[Cp] País de publicação:Korea (South)
[La] Idioma:eng
[Ab] Resumo:A novel endodextranase isolated from Paenibacillus sp. was found to produce isomaltotetraose and small amounts of cycloisomaltooligosaccharides with a degree of polymerization of 7-14 from dextran. To determine the active site, the enzyme was modified with 1-ethyl-3-[3- (dimethylamino)-propyl]-carbodiimide (EDC) and α-epoxyalkyl α-glucosides (EAGs), an affinity labeling reagent. The inactivation followed pseudo first-order kinetics. Kinetic analysis and chemical modification using EDC and EAGs indicated that carboxyl groups are essential for the enzymatic activity. Three Asp and one Glu residues were identified as candidate catalytic amino acids, since these residues are completely conserved across the GH family of 66 enzymes. Replacement of Asp189, Asp340, or Glu412 completely abolished the enzyme activity, indicating that these residues are essential for catalytic activity.
[Mh] Termos MeSH primário: Aminoácidos/química
Dextranase/química
Paenibacillus/enzimologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Aminoácidos/metabolismo
Catálise
Domínio Catalítico
Cromatografia em Camada Delgada
Dextranase/metabolismo
Dextranos/química
Dextranos/metabolismo
Ativação Enzimática
Concentração de Íons de Hidrogênio
Cinética
Mutagênese Sítio-Dirigida
Paenibacillus/química
Conformação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids); 0 (Dextrans); EC 3.2.1.11 (Dextranase)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170406
[Lr] Data última revisão:
170406
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160225
[St] Status:MEDLINE
[do] DOI:10.4014/jmb.1601.01014


  7 / 446 MEDLINE  
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[PMID]:26744310
[Au] Autor:Walker GV; Heng NC; Carne A; Tagg JR; Wescombe PA
[Ad] Endereço:1​Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand.
[Ti] Título:Salivaricin E and abundant dextranase activity may contribute to the anti-cariogenic potential of the probiotic candidate Streptococcus salivarius JH.
[So] Source:Microbiology;162(3):476-86, 2016 Mar.
[Is] ISSN:1465-2080
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Dental caries is an infectious disease that is continuing to increase in prevalence, reducing the quality of life for millions worldwide as well as causing considerable expense, with an estimated US$108 billion spent on dental care in the USA each year. Oral probiotics are now being investigated to determine whether they could play a role in the prevention and treatment of this disease. Streptococcus salivarius strain JH is a potential probiotic candidate that produces multiple proteinaceous antimicrobials (bacteriocins), the inhibitory spectrum of which includes Streptococcus mutans, one of the principal causative agents of dental caries. The genome of strain JH has previously been shown to contain the biosynthetic loci for the bacteriocins salivaricin A3, streptin and streptococcin SA-FF22. Here we show that strain JH also produces salivaricin E, a 32 aa lantibiotic with a mass of 3565.9 Da, which is responsible for the inhibition of S. mutans growth. In addition, strain JH was shown to produce dextranase, an enzyme that hydrolyses (1 → 6)-α-D-glucosidic linkages, at levels higher than any other S. salivarius tested. In vitro testing showed that partial hydrolysis of the exopolymeric substances of S. mutans, using strain JH dextranase, improved the anti-S. mutans inhibitory activity of the lytic bacteriocin, zoocin A. The multiple bacteriocin and dextranase activities of strain JH support its candidature for development as an oral probiotic.
[Mh] Termos MeSH primário: Bacteriocinas/metabolismo
Dextranase/metabolismo
Probióticos/farmacologia
Streptococcus salivarius/enzimologia
Streptococcus salivarius/metabolismo
[Mh] Termos MeSH secundário: Bacteriocinas/química
Peso Molecular
Streptococcus mutans/efeitos dos fármacos
Streptococcus mutans/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacteriocins); EC 3.2.1.11 (Dextranase)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160109
[St] Status:MEDLINE
[do] DOI:10.1099/mic.0.000237


  8 / 446 MEDLINE  
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[PMID]:26513248
[Au] Autor:Villalba ML; Susana Sáez J; Del Monaco S; Lopes CA; Sangorrín MP
[Ad] Endereço:Grupo de Biodiversidad y Biotecnología de Levaduras, Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas (PROBIEN), Consejo Nacional de Investigaciones Científicas y Tecnológicas, Universidad Nacional del Comahue, Buenos Aires 1400, (8300) Neuquén
[Ti] Título:TdKT, a new killer toxin produced by Torulaspora delbrueckii effective against wine spoilage yeasts.
[So] Source:Int J Food Microbiol;217:94-100, 2016 Jan 18.
[Is] ISSN:1879-3460
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Microbiological spoilage is a major concern throughout the wine industry, and control tools are limited. This paper addresses the identification and partial characterization of a new killer toxin from Torulaspora delbrueckii with potential biocontrol activity of Brettanomyces bruxellensis, Pichia guilliermondii, Pichia manshurica and Pichia membranifaciens wine spoilage. A panel of 18 different wine strains of T. delbrueckii killer yeasts was analysed, and the strain T. delbrueckii NPCC 1033 (TdKT producer) showed a significant inhibitory effect on the growth of all different spoilage yeasts evaluated. The TdKT toxin was then subjected to a partial biochemical characterization. Its estimated molecular weight was N30 kDa and it showed glucanase and chitinase enzymatic activities. The killer activity was stable between pH 4.2 and 4.8 and inactivated at temperature above 40 °C. Pustulan and chitin ­ but not other cell wall polysaccharides ­ prevented sensitive yeast cells from being killed by TdKT, suggesting that those may be the first toxin targets in the cell wall. TdKT provoked an increase in necrosis cell death after 3 h treatment and apoptotic cell death after 24 h showing time dependence in its mechanisms of action. Killer toxin extracts were active at oenological conditions, confirming their potential use as a biocontrol tool in winemaking.
[Mh] Termos MeSH primário: Fatores Matadores de Levedura/farmacologia
Pichia/efeitos dos fármacos
Torulaspora/metabolismo
Vinho/microbiologia
[Mh] Termos MeSH secundário: Quitinases/metabolismo
Dextranase/metabolismo
Polissacarídeos Fúngicos/metabolismo
Fatores Matadores de Levedura/química
Fatores Matadores de Levedura/isolamento & purificação
Testes de Sensibilidade Microbiana
Temperatura Ambiente
Torulaspora/patogenicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Fungal Polysaccharides); 0 (Killer Factors, Yeast); EC 3.2.1.11 (Dextranase); EC 3.2.1.14 (Chitinases)
[Em] Mês de entrada:1607
[Cu] Atualização por classe:161126
[Lr] Data última revisão:
161126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151030
[St] Status:MEDLINE


  9 / 446 MEDLINE  
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[PMID]:26494689
[Au] Autor:Suzuki N; Kishine N; Fujimoto Z; Sakurai M; Momma M; Ko JA; Nam SH; Kimura A; Kim YM
[Ad] Endereço:Biomolecular Research Unit, National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba 305-8602, Japan; zui@affrc.go.jp u9897854@jnu.ac.kr.
[Ti] Título:Crystal structure of thermophilic dextranase from Thermoanaerobacter pseudethanolicus.
[So] Source:J Biochem;159(3):331-9, 2016 Mar.
[Is] ISSN:1756-2651
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The crystal structures of the wild type and catalytic mutant Asp-312→Gly in complex with isomaltohexaose of endo-1,6-dextranase from the thermophilic bacterium Thermoanaerobacter pseudethanolicus (TpDex), belonging to the glycoside hydrolase family 66, were determined. TpDex consists of three structural domains, a catalytic domain comprising an (ß/α)8-barrel and two ß-domains located at both N- and C-terminal ends. The isomaltohexaose-complex structure demonstrated that the isomaltohexaose molecule was bound across the catalytic site, showing that TpDex had six subsites (-4 to +2) in the catalytic cleft. Marked movement of the Trp-376 side-chain along with loop 6, which was the side wall component of the cleft at subsite +1, was observed to occupy subsite +1, indicating that it might expel the cleaved aglycone subsite after the hydrolysis reaction. Structural comparison with other mesophilic enzymes indicated that several structural features of TpDex, loop deletion, salt bridge and surface-exposed charged residue, may contribute to thermostability.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Dextranase/química
Oligossacarídeos/química
Thermoanaerobacter/enzimologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Bactérias/genética
Domínio Catalítico
Cristalografia por Raios X
Dextranase/genética
Estabilidade Enzimática
Hidrólise
Dados de Sequência Molecular
Mutagênese Sítio-Dirigida
Estrutura Secundária de Proteína
Homologia de Sequência de Aminoácidos
Especificidade por Substrato
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Oligosaccharides); 6175-02-6 (isomaltohexose); EC 3.2.1.11 (Dextranase)
[Em] Mês de entrada:1608
[Cu] Atualização por classe:160224
[Lr] Data última revisão:
160224
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151024
[St] Status:MEDLINE
[do] DOI:10.1093/jb/mvv104


  10 / 446 MEDLINE  
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[PMID]:24845476
[Au] Autor:Rai G; Yadav AK; Jain NK; Agrawal GP
[Ad] Endereço:a Pharmaceutics Research Laboratory, Department of Pharmaceutical Sciences , Dr. Hari Singh Gour University , Sagar , Madhya Pradesh , India.
[Ti] Título:Eudragit-coated dextran microspheres of 5-fluorouracil for site-specific delivery to colon.
[So] Source:Drug Deliv;23(1):328-37, 2016.
[Is] ISSN:1521-0464
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Objective of the present investigation was to prepare and evaluate the potential of enteric coated dextran microspheres for colon targeting of 5-fluorouracil (5-FU). Dextran microspheres were prepared by emulsification-crosslinking method and the formulation variables studied included different molecular weights of dextran, drug:polymer ratio, volume of crosslinking agent, stirring speed and time. Enteric coating (Eudragit S-100) of dextran microspheres was performed by oil-in-oil solvent evaporation method using different coat:core ratios (4:1 or 8:1). Uncoated and coated dextran microspheres were characterized by particle size, surface morphology, entrapment efficiency, DSC, in vitro drug release in the presence of dextranase and 2% rat cecal contents. The release study of 5-FU from coated dextran microspheres was pH dependent. No release was observed at acidic pH; however, the drug was released quickly where Eudragit starts solublizing there was continuous release of drug from the microspheres. Organ distribution study was suggested that coated dextran microspheres retard the release of drug in gastric and intestinal pH environment and released of drug from microspheres in colon due to the degradation of dextran by colonic enzymes.
[Mh] Termos MeSH primário: Antimetabólitos Antineoplásicos/administração & dosagem
Colo/efeitos dos fármacos
Colo/metabolismo
Fluoruracila/administração & dosagem
[Mh] Termos MeSH secundário: Animais
Antimetabólitos Antineoplásicos/farmacocinética
Química Farmacêutica
Reagentes para Ligações Cruzadas
Preparações de Ação Retardada
Dextranase/química
Dextranos
Sistemas de Liberação de Medicamentos
Excipientes
Fluoruracila/farmacocinética
Microesferas
Tamanho da Partícula
Ácidos Polimetacrílicos
Ratos
Solventes
Distribuição Tecidual
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antimetabolites, Antineoplastic); 0 (Cross-Linking Reagents); 0 (Delayed-Action Preparations); 0 (Dextrans); 0 (Excipients); 0 (Polymethacrylic Acids); 0 (Solvents); 25086-15-1 (methylmethacrylate-methacrylic acid copolymer); EC 3.2.1.11 (Dextranase); U3P01618RT (Fluorouracil)
[Em] Mês de entrada:1610
[Cu] Atualização por classe:170103
[Lr] Data última revisão:
170103
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140522
[St] Status:MEDLINE
[do] DOI:10.3109/10717544.2014.913733



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