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[PMID]:27770417
[Au] Autor:Roy I; Mukherjee J; Gupta MN
[Ad] Endereço:Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, Punjab, India.
[Ti] Título:Cross-Linked Enzyme Aggregates for Applications in Aqueous and Nonaqueous Media.
[So] Source:Methods Mol Biol;1504:109-123, 2017.
[Is] ISSN:1940-6029
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Extensive cross-linking of a precipitate of a protein by a cross-linking reagent (glutaraldehyde has been most commonly used) creates an insoluble enzyme preparation called cross-linked enzyme aggregates (CLEAs). CLEAs show high stability and performance in conventional aqueous as well as nonaqueous media. These are also stable at fairly high temperatures. CLEAs with more than one kind of enzyme activity can be prepared, and such CLEAs are called combi-CLEAs or multipurpose CLEAs. Extent of cross-linking often influences their morphology, stability, activity, and enantioselectivity.
[Mh] Termos MeSH primário: Reagentes para Ligações Cruzadas/química
Enzimas Imobilizadas/química
Glutaral/química
[Mh] Termos MeSH secundário: Animais
Aspergillus niger/enzimologia
Burkholderia cepacia/enzimologia
Candida/enzimologia
Bovinos
Estabilidade Enzimática
Enzimas Imobilizadas/metabolismo
Hidrolases/química
Hidrolases/metabolismo
Lipase/química
Lipase/metabolismo
Penicilina Amidase/química
Penicilina Amidase/metabolismo
Poligalacturonase/química
Poligalacturonase/metabolismo
Agregados Proteicos
Soroalbumina Bovina/metabolismo
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cross-Linking Reagents); 0 (Enzymes, Immobilized); 0 (Protein Aggregates); 27432CM55Q (Serum Albumin, Bovine); EC 3.- (Hydrolases); EC 3.1.1.3 (Lipase); EC 3.2.1.15 (Polygalacturonase); EC 3.5.1.11 (Penicillin Amidase); T3C89M417N (Glutaral)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180115
[Lr] Data última revisão:
180115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161023
[St] Status:MEDLINE


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[PMID]:28115011
[Au] Autor:Lakowitz A; Krull R; Biedendieck R
[Ad] Endereço:Institute of Biochemical Engineering, Technische Universität Braunschweig, Rebenring 56, 38106, Braunschweig, Germany.
[Ti] Título:Recombinant production of the antibody fragment D1.3 scFv with different Bacillus strains.
[So] Source:Microb Cell Fact;16(1):14, 2017 Jan 23.
[Is] ISSN:1475-2859
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Different strains of the genus Bacillus are versatile candidates for the industrial production and secretion of heterologous proteins. They can be cultivated quite easily, show high growth rates and are usually non-pathogenic and free of endo- and exotoxins. They have the ability to secrete proteins with high efficiency into the growth medium, which allows cost-effective downstream purification processing. Some of the most interesting and challenging heterologous proteins are recombinant antibodies and antibody fragments. They are important and suitable tools in medical research for analytics, diagnostics and therapy. The smallest conventional antibody fragment with high-affinity binding to an antigen is the single-chain fragment variable (scFv). Here, different strains of the genus Bacillus were investigated using diverse cultivation systems for their suitability to produce and secret a recombinant scFv. RESULTS: Extracellular production of lysozyme-specific scFv D1.3 was realized by constructing a plasmid with a xylose-inducible promoter optimized for Bacillus megaterium and the D1.3scFv gene fused to the coding sequence of the LipA signal peptide from B. megaterium. Functional scFv was successfully secreted with B. megaterium MS941, Bacillus licheniformis MW3 and the three Bacillus subtilis strains 168, DB431 and WB800N differing in the number of produced proteases. Starting with shake flasks (150 mL), the bioprocess was scaled down to microtiter plates (1250 µL) as well as scaled up to laboratory-scale bioreactors (2 L). The highest extracellular concentration of D1.3 scFv (130 mg L ) and highest space-time-yield (8 mg L h ) were accomplished with B. subtilis WB800N, a strain deficient in eight proteases. These results were reproduced by the production and secretion of a recombinant penicillin G acylase (Pac). CONCLUSIONS: The genus Bacillus provides high potential microbial host systems for the secretion of challenging heterologous proteins like antibody fragments and large proteins at high titers. In this study, the highest extracellular concentration and space-time-yield of a recombinant antibody fragment for a Gram-positive bacterium so far was achieved. The successful interspecies use of the here-designed plasmid originally optimized for B. megaterium was demonstrated by two examples, an antibody fragment and a penicillin G acylase in up to five different Bacillus strains.
[Mh] Termos MeSH primário: Bacillus megaterium/imunologia
Bacillus/imunologia
Proteínas Recombinantes/biossíntese
Anticorpos de Cadeia Única/biossíntese
Anticorpos de Cadeia Única/genética
[Mh] Termos MeSH secundário: Bacillus/classificação
Bacillus/genética
Bacillus/metabolismo
Bacillus megaterium/genética
Bacillus megaterium/metabolismo
Proteínas de Bactérias/genética
Reatores Biológicos
Meios de Cultura
Microbiologia Industrial/métodos
Penicilina Amidase/genética
Penicilina Amidase/metabolismo
Peptídeo Hidrolases/metabolismo
Plasmídeos
Regiões Promotoras Genéticas/genética
Proteínas Recombinantes/imunologia
Proteínas Recombinantes/metabolismo
Anticorpos de Cadeia Única/análise
Anticorpos de Cadeia Única/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Culture Media); 0 (LipA protein, Bacteria); 0 (Recombinant Proteins); 0 (Single-Chain Antibodies); EC 3.4.- (Peptide Hydrolases); EC 3.5.1.11 (Penicillin Amidase)
[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:170125
[St] Status:MEDLINE
[do] DOI:10.1186/s12934-017-0625-9


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[PMID]:28038956
[Au] Autor:Adediran SA; Pratt RF
[Ad] Endereço:Department of Chemistry, Wesleyan University, Middletown, CT 06459, USA.
[Ti] Título:Penicillin acylase and O-aryloxycarbonyl hydroxamates: Two acyl-enzymes, one leading to hydrolysis, the other to inactivation.
[So] Source:Arch Biochem Biophys;614:65-71, 2017 Jan 15.
[Is] ISSN:1096-0384
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:O-Aryloxycarbonyl hydroxamates have previously been shown to covalently inactivate serine/amine amidohydrolases such as class C ß-lactamases and a N-terminal hydrolase, the proteasome. We report here reactions between O-aryloxycarbonyl hydroxamates and another N-terminal hydrolase, penicillin acylase. O-Aryloxycarbonyl hydroxamates, as non-symmetric carbonates, have two different leaving groups attached to the reactive central carbonyl group. We propose that these compounds can bind to the active site in either of two orientations and that either leaving group can be displaced from either orientation. In the present case we detected from kinetics experiments two distinct acyl-enzymes, one of which is subject to normal hydrolysis and the other to inactivation. Non-symmetric carbonates therefore can be very versatile enzyme inactivators.
[Mh] Termos MeSH primário: Inibidores Enzimáticos/química
Ácidos Hidroxâmicos/química
Penicilina Amidase/química
[Mh] Termos MeSH secundário: Domínio Catalítico
Reagentes para Ligações Cruzadas/química
Escherichia coli/enzimologia
Concentração de Íons de Hidrogênio
Hidrólise
Cinética
Complexo de Endopeptidases do Proteassoma/química
Domínios Proteicos
Serina/química
Temperatura Ambiente
beta-Lactamases/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cross-Linking Reagents); 0 (Enzyme Inhibitors); 0 (Hydroxamic Acids); 452VLY9402 (Serine); EC 3.4.25.1 (Proteasome Endopeptidase Complex); EC 3.5.1.11 (Penicillin Amidase); EC 3.5.2.6 (beta-Lactamases)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170515
[Lr] Data última revisão:
170515
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170101
[St] Status:MEDLINE


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[PMID]:27933456
[Au] Autor:Sunder AV; Utari PD; Ramasamy S; van Merkerk R; Quax W; Pundle A
[Ad] Endereço:Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India.
[Ti] Título:Penicillin V acylases from gram-negative bacteria degrade N-acylhomoserine lactones and attenuate virulence in Pseudomonas aeruginosa.
[So] Source:Appl Microbiol Biotechnol;101(6):2383-2395, 2017 Mar.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Virulence pathways in gram-negative pathogenic bacteria are regulated by quorum sensing mechanisms, through the production and sensing of N-acylhomoserine lactone (AHL) signal molecules. Enzymatic degradation of AHLs leading to attenuation of virulence (quorum quenching) could pave the way for the development of new antibacterials. Penicillin V acylases (PVAs) belong to the Ntn hydrolase superfamily, together with AHL acylases. PVAs are exploited widely in the pharmaceutical industry, but their role in the natural physiology of their native microbes is not clearly understood. This report details the characterization of AHL degradation activity by homotetrameric PVAs from two gram-negative plant pathogenic bacteria, Pectobacterium atrosepticum (PaPVA) and Agrobacterium tumefaciens (AtPVA). Both the PVAs exhibited substrate specificity for degrading long-chain AHLs. Exogenous addition of these enzymes into Pseudomonas aeruginosa greatly diminished the production of elastase and pyocyanin and biofilm formation and increased the survival rate in an insect model of acute infection. Subtle structural differences in the PVA active site that regulate specificity for acyl chain length have been characterized, which could reflect the evolution of AHL-degrading acylases in relation to the environment of the bacteria that produce them and also provide strategies for enzyme engineering. The potential for using these enzymes as therapeutic agents in clinical applications and a few ideas about their possible significance in microbial physiology have also been discussed.
[Mh] Termos MeSH primário: Acil-Butirolactonas/química
Proteínas de Bactérias/química
Regulação Bacteriana da Expressão Gênica
Penicilina Amidase/química
Pseudomonas aeruginosa/genética
Pseudomonas aeruginosa/patogenicidade
[Mh] Termos MeSH secundário: Acil-Butirolactonas/metabolismo
Agrobacterium tumefaciens/enzimologia
Agrobacterium tumefaciens/genética
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Biofilmes/crescimento & desenvolvimento
Domínio Catalítico
Clonagem Molecular
Escherichia coli/genética
Escherichia coli/metabolismo
Hidrólise
Modelos Moleculares
Elastase Pancreática/biossíntese
Pectobacterium/enzimologia
Pectobacterium/genética
Penicilina Amidase/genética
Penicilina Amidase/metabolismo
Conformação Proteica
Pseudomonas aeruginosa/metabolismo
Piocianina/biossíntese
Percepção de Quorum
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Especificidade por Substrato
Virulência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acyl-Butyrolactones); 0 (Bacterial Proteins); 0 (Recombinant Proteins); 9OQM399341 (Pyocyanine); EC 3.4.21.36 (Pancreatic Elastase); EC 3.5.1.11 (Penicillin Amidase)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170307
[Lr] Data última revisão:
170307
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161210
[St] Status:MEDLINE
[do] DOI:10.1007/s00253-016-8031-5


  5 / 740 MEDLINE  
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[PMID]:27871384
[Au] Autor:Jiang Y; Sun W; Wang Y; Wang L; Zhou L; Gao J; He Y; Ma L; Zhang X
[Ad] Endereço:School of Chemical Engineering and Technology, Hebei University of Technology, Guangrong Road, Hongqiao District, Tianjin 300130, PR China.
[Ti] Título:Protein-based inverse opals: A novel support for enzyme immobilization.
[So] Source:Enzyme Microb Technol;96:42-46, 2017 Jan.
[Is] ISSN:1879-0909
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this study, protein-based inverse opals were prepared for the first time by using the colloidal crystal templating method. The preparation process involved three steps including filling the templates with protein molecules, crosslinking, and template removal. The obtained inverse opals were used to immobilize Penicillin G acylase (PGA) because of its intrinsic biocompatible property. The immobilization process was optimized and the properties of the immobilized PGA (PGA@IO) were investigated. PGA@IO exhibited improved thermal and pH stability compared with its free counterpart. After reusing nine times, it retained 70% of the initial activity. Besides, the PGA@IO retained high activity during the hydrolysis reactions in continuous catalysis in packed-bed reactor (PBR) after 15 days.
[Mh] Termos MeSH primário: Enzimas Imobilizadas
Proteínas/química
[Mh] Termos MeSH secundário: Animais
Biocatálise
Materiais Biocompatíveis/química
Reatores Biológicos
Biotecnologia
Bovinos
Coloides
Reagentes para Ligações Cruzadas
Cristalização
Estabilidade Enzimática
Enzimas Imobilizadas/metabolismo
Hidrólise
Penicilina Amidase/metabolismo
Soroalbumina Bovina/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biocompatible Materials); 0 (Colloids); 0 (Cross-Linking Reagents); 0 (Enzymes, Immobilized); 0 (Proteins); 27432CM55Q (Serum Albumin, Bovine); EC 3.5.1.11 (Penicillin Amidase)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161123
[St] Status:MEDLINE


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[PMID]:27817045
[Au] Autor:Liu K; Li S; Pang X; Xu Z; Li D; Xu H
[Ad] Endereço:State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, No. 30 South of Puzhu Road, Pukou District, 211800, Nanjing, China.
[Ti] Título:Enhanced Enzymatic Synthesis of a Cephalosporin, Cefadroclor, in the Presence of Organic Co-solvents.
[So] Source:Appl Biochem Biotechnol;182(1):29-40, 2017 May.
[Is] ISSN:1559-0291
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this study, we investigated the enzymatic synthesis of a semi-synthetic cephalosporin, cefadroclor, from 7-aminodesacetoxymethyl-3-chlorocephalosporanic acid (7-ACCA) and p-OH-phenylglycine methyl ester (D-HPGM) using immobilized penicillin G acylase (IPA) in organic co-solvents. Ethylene glycol (EG) was employed as a component of the reaction mixture to improve the yield of cefadroclor. EG was found to increase the yield of cefadroclor by 15-45%. An investigation of altered reaction parameters including type and concentration of organic solvents, pH of reaction media, reaction temperature, molar ratio of substrates, enzyme loading, and IPA recycling was carried out in the buffer mixture. The best result was a 76.5% conversion of 7-ACCA, which was obtained from the reaction containing 20% EG (v/v), D-HPGM to 7-ACCA molar ratio of 4:1 and pH 6.2, catalyzed by 16 IU mL IPA at 20 °C for 10 h. Under the optimum conditions, no significant loss of IPA activity was found after seven repeated reaction cycles. In addition, cefadroclor exhibited strong inhibitory activity against yeast, Bacillus subtilis NX-2, and Escherichia coli and weaker activity against Staphylococcus aureus and Pseudomonas aeruginosa. Cefadroclor is a potential antibiotic with activity against common pathogenic microorganisms.
[Mh] Termos MeSH primário: Cefalosporinas/biossíntese
Enzimas Imobilizadas/metabolismo
Etilenoglicol/química
Penicilina Amidase/metabolismo
Solventes/química
[Mh] Termos MeSH secundário: Anti-Infecciosos/química
Anti-Infecciosos/metabolismo
Anti-Infecciosos/farmacologia
Bacillus subtilis/efeitos dos fármacos
Bacillus subtilis/crescimento & desenvolvimento
Cefalosporinas/química
Cefalosporinas/farmacologia
Enzimas Imobilizadas/química
Escherichia coli/efeitos dos fármacos
Escherichia coli/crescimento & desenvolvimento
Glicina/análogos & derivados
Glicina/química
Glicina/metabolismo
Concentração de Íons de Hidrogênio
Penicilina Amidase/química
Pseudomonas aeruginosa/efeitos dos fármacos
Pseudomonas aeruginosa/crescimento & desenvolvimento
Saccharomyces cerevisiae/efeitos dos fármacos
Saccharomyces cerevisiae/crescimento & desenvolvimento
Staphylococcus aureus/efeitos dos fármacos
Staphylococcus aureus/crescimento & desenvolvimento
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Infective Agents); 0 (Cephalosporins); 0 (Enzymes, Immobilized); 0 (Solvents); 26682-99-5 (methyl phenylglycine); EC 3.5.1.11 (Penicillin Amidase); FC72KVT52F (Ethylene Glycol); TE7660XO1C (Glycine)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170619
[Lr] Data última revisão:
170619
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161107
[St] Status:MEDLINE
[do] DOI:10.1007/s12010-016-2308-0


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[PMID]:27557716
[Au] Autor:Tian Y; Huang X; Li Q; Zhu Y
[Ad] Endereço:Department of Chemical Engineering, Tsinghua University, Beijing, 100084, People's Republic of China.
[Ti] Título:Computational design of variants for cephalosporin C acylase from Pseudomonas strain N176 with improved stability and activity.
[So] Source:Appl Microbiol Biotechnol;101(2):621-632, 2017 Jan.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:In this report, redesigning cephalosporin C acylase from the Pseudomonas strain N176 revealed that the loss of stability owing to the introduced mutations at the active site can be recovered by repacking the nearby hydrophobic core regions. Starting from a quadruple mutant M31ßF/H57ßS/V68ßA/H70ßS, whose decrease in stability is largely owing to the mutation V68ßA at the active site, we employed a computational enzyme design strategy that integrated design both at hydrophobic core regions for stability enhancement and at the active site for activity improvement. Single-point mutations L154ßF, Y167ßF, L180ßF and their combinations L154ßF/L180ßF and L154ßF/Y167ßF/L180ßF were found to display improved stability and activity. The two-point mutant L154ßF/L180ßF increased the protein melting temperature (T ) by 11.7 °C and the catalytic efficiency V /K by 57 % compared with the values of the starting quadruple mutant. The catalytic efficiency of the resulting sixfold mutant M31ßF/H57ßS/V68ßA/H70ßS/L154ßF/L180ßF is recovered to become comparable to that of the triple mutant M31ßF/H57ßS/H70ßS, but with a higher T . Further experiments showed that single-point mutations L154ßF, L180ßF, and their combination contribute no stability enhancement to the triple mutant M31ßF/H57ßS/H70ßS. These results verify that the lost stability because of mutation V68ßA at the active site was recovered by introducing mutations L154ßF and L180ßF at hydrophobic core regions. Importantly, mutation V68ßA in the six-residue mutant provides more space to accommodate the bulky side chain of cephalosporin C, which could help in designing cephalosporin C acylase mutants with higher activities and the practical one-step enzymatic route to prepare 7-aminocephalosporanic acid at industrial-scale levels.
[Mh] Termos MeSH primário: Cefalosporinas/metabolismo
Penicilina Amidase/química
Penicilina Amidase/metabolismo
Engenharia de Proteínas/métodos
Pseudomonas/enzimologia
[Mh] Termos MeSH secundário: Estabilidade Enzimática
Cinética
Proteínas Mutantes/química
Proteínas Mutantes/genética
Proteínas Mutantes/metabolismo
Penicilina Amidase/genética
Mutação Puntual
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cephalosporins); 0 (Mutant Proteins); 3XIY7HJT5L (cephalosporin C); EC 3.5.1.11 (Penicillin Amidase); EC 3.5.1.11 (glutarylamidocephalosporanic acid acylase)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170117
[Lr] Data última revisão:
170117
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160826
[St] Status:MEDLINE
[do] DOI:10.1007/s00253-016-7796-x


  8 / 740 MEDLINE  
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[PMID]:26986755
[Au] Autor:Avinash VS; Chauhan PD; Gaikwad S; Pundle A
[Ad] Endereço:a Division of Biochemical Sciences , CSIR-National Chemical Laboratory , Pune , India.
[Ti] Título:Biotransformation of penicillin V to 6-aminopenicillanic acid using immobilized whole cells of E. coli expressing a highly active penicillin V acylase.
[So] Source:Prep Biochem Biotechnol;47(1):52-57, 2017 Jan 02.
[Is] ISSN:1532-2297
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The production of 6-aminopenicillanic acid (6-APA) is a key step in the manufacture of semisynthetic antibiotics in the pharmaceutical industry. The penicillin G acylase from Escherichia coli has long been utilized for this purpose. However, the use of penicillin V acylases (PVA) presents some advantages including better stability and higher conversion rates. The industrial application of PVAs has so far been limited due to the nonavailability of suitable bacterial strains and cost issues. In this study, whole-cell immobilization of a recombinant PVA enzyme from Pectobacterium atrosepticum expressed in E. coli was performed. Membrane permeabilization with detergent was used to enhance the cell-bound PVA activity, and the cells were encapsulated in calcium alginate beads and cross-linked with glutaraldehyde. Optimization of parameters for the biotransformation by immobilized cells showed that full conversion of pen V to 6-APA could be achieved within 1 hr at pH 5.0 and 35°C, till 4% (w/v) concentration of the substrate. The beads could be stored for 28 days at 4°C with minimal loss in activity and were reusable up to 10 cycles with 1-hr hardening in CaCl between each cycle. The high enzyme productivity of the PVA enzyme system makes a promising case for its application for 6-APA production in the industry.
[Mh] Termos MeSH primário: Biotransformação
Escherichia coli/genética
Ácido Penicilânico/análogos & derivados
Penicilina Amidase/metabolismo
Penicilina V/farmacocinética
[Mh] Termos MeSH secundário: Alginatos/química
Ácido Glucurônico/química
Ácidos Hexurônicos/química
Microscopia Eletrônica de Varredura
Ácido Penicilânico/metabolismo
Penicilina Amidase/genética
Permeabilidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alginates); 0 (Hexuronic Acids); 87-53-6 (Penicillanic Acid); 8A5D83Q4RW (Glucuronic Acid); 8C3Z4148WZ (alginic acid); EC 3.5.1.11 (Penicillin Amidase); QR0C4R7XVN (aminopenicillanic acid); Z61I075U2W (Penicillin V)
[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:160318
[St] Status:MEDLINE
[do] DOI:10.1080/10826068.2016.1163580


  9 / 740 MEDLINE  
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[PMID]:27494735
[Au] Autor:Nupur N; Ashish EY; Debnath M
[Ti] Título:Preparation and Biochemical Property of Penicillin G Amidase-Loaded Alginate and Alginate/Chitosan Hydrogel Beads.
[So] Source:Recent Pat Biotechnol;10(1):121-132, 2016.
[Is] ISSN:2212-4012
[Cp] País de publicação:United Arab Emirates
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Penicillin G amidase (PGA) (EC 3.5.1.11) are enzymes that are mainly involved in the synthesis of semi-synthetic }-lactam antibiotics. Soluble PGA is costly and lacks long term operational stability. We revised most of the patents related to Penicillin G amidase (PGA) immobilization in the section "Recent Patents on Immobilized Penicillin G Amidase". OBJECTIVE: The aim of this work was to study comparative biochemical property of PGA enzyme immobilized in two hydro-gel beads - Ca-alginate and alginate+chitosan hybrid and morphologically characterised by SEM. METHODS: PGA immobilized in alginate+chitosan hybrid bead shows high pH and thermal stability. Km, Vmax and Effectiveness factor (1) value of free PGA were 56.19 mg/ml, 1.786 U/ml and 1, respectively. These parameters for PGA immobilized alginate beads were 64.84 mg/ml, 0.781U/ml and 0.437, respectively and for PGA immobilized alginate+chitosan hybrid beads were 87.08 mg/ml, 0.622 U/ml and 0.348, respectively. RESULTS: Immobilized PGA on alginate+chitosan hybrid beads gave the highest thermal stability, reusability and storage stability than alginate immobilized PGA. CONCLUSION: The entrapment of PGA on alginate+chitosan hybrid beads revealed several advantages and could be used in 6APA (6- aminopenicillanic acid) production.
[Mh] Termos MeSH primário: Alginatos/química
Quitosana/química
Hidrogel de Polietilenoglicol-Dimetacrilato/química
Penicilina Amidase/química
Penicilina G/química
[Mh] Termos MeSH secundário: Ácido Glucurônico/química
Ácidos Hexurônicos/química
Concentração de Íons de Hidrogênio
Patentes como Assunto
Ácido Penicilânico/análogos & derivados
Ácido Penicilânico/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alginates); 0 (Hexuronic Acids); 25852-47-5 (Hydrogel, Polyethylene Glycol Dimethacrylate); 87-53-6 (Penicillanic Acid); 8A5D83Q4RW (Glucuronic Acid); 8C3Z4148WZ (alginic acid); 9012-76-4 (Chitosan); EC 3.5.1.11 (Penicillin Amidase); Q42T66VG0C (Penicillin G); QR0C4R7XVN (aminopenicillanic acid)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160806
[St] Status:MEDLINE


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[PMID]:27398443
[Au] Autor:Liu R; Fan J; Zhang Y; Wang P; Shen X
[Ti] Título:Immobilization and Characterization of Penicillin G Acylase (PGA) Immobilized on Magnetic Ni0.5Zn0.5Fe2O4 Nanoparticles.
[So] Source:J Nanosci Nanotechnol;16(1):182-8, 2016 Jan.
[Is] ISSN:1533-4880
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Magnetic Ni0.5Zn0.5Fe2O4 nanoparticles were prepared via the solution combustion process and their microstructure and magnetic properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The as-prepared magnetic Ni0.5Zn0.5Fe2O4 nanoparticles are characterized with average grain size of about 20 nm and magnetization of 90.3 Am²/kg. The surface of magnetic Ni0.5Zn0.5Fe2O4 nanoparticles was modified by use of sodium silicate and N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride, and the penicillin G acylase (PGA) was successfully immobilized on the surface-modified magnetic Ni0.5Zn0.5Fe2O4 nanoparticles. The results show that the activity for the immobilized PGA is affected less by pH and temperature than that for the free PGA, and the immobilized PGA exhibits a high effective activity, good stability of enzyme catalyst. This immobilized PGA on magnetic Ni0.5Zn0.5Fe2O4 nanoparticles can be separated from the solution by the external magnetic field for cyclic utilization, and they could retain about 70% of initial enzyme activity after 11 consecutive operations. The kinetic parameters (Km and Vmax) were determined, and the value of Km for the immobilized PGA (204.53 mmol/L) is higher than that of the free enzyme (3.50 mmol/L), while Vmax (1.93 mmol/min) is also larger than that of the free enzyme (0.838 mmol/min).
[Mh] Termos MeSH primário: Enzimas Imobilizadas/química
Compostos Férricos/química
Nanopartículas/química
Níquel/química
Penicilina Amidase/química
Zinco/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Enzymes, Immobilized); 0 (Ferric Compounds); 1K09F3G675 (ferric oxide); 7OV03QG267 (Nickel); EC 3.5.1.11 (Penicillin Amidase); J41CSQ7QDS (Zinc)
[Em] Mês de entrada:1608
[Cu] Atualização por classe:160711
[Lr] Data última revisão:
160711
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160712
[St] Status:MEDLINE



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