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  1 / 694 MEDLINE  
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[PMID]:28873987
[Au] Autor:Goswami S; Das S; Datta S
[Ad] Endereço:Protein Engineering Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research, Mohanpur 741246, India.
[Ti] Título:Understanding the role of residues around the active site tunnel towards generating a glucose-tolerant ß-glucosidase from Agrobacterium tumefaciens 5A.
[So] Source:Protein Eng Des Sel;30(7):523-530, 2017 Jul 01.
[Is] ISSN:1741-0134
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Most ß-glucosidases are subjected to inhibition by the final hydrolysis product glucose resulting in the accumulation of cellobiose and oligosaccharides. This accumulated cellobiose and oligosaccharides further inhibit the activities of endoglucanase and cellobiohydrolases, resulting in the inhibition of cellulose degradation and a more expensive biofuel. To elucidate the mechanism(s) of glucose tolerance, we designed and characterised six mutations of a moderately glucose-tolerant ß-glucosidase (H0HC94) from the mesophilic bacterium Agrobacterium tumefaciens 5A. The hydrophobicity and steric were varied across non-conserved residues in specific regions of the active site tunnel. In contrast to the uncompetitive inhibition of WT enzyme by glucose, C174V and H229S are competitively inhibited pointing towards a possible glucose-binding site in the protein at these positions. Increasing hydrophobicity at the +1 subsite and increasing hydrophobicity and steric at +2 subsites seemed to be critical for glucose tolerance for this BG. Additionally, in L178E, specific activity was 1.8 times higher on the natural substrate cellobiose while both W127F and L178E mutants showed an enhancement in thermostability. The kinetic stability of W127F, V176A, L178A and L178E also increased between 2- and 3-folds compared to WT. Our results indicate that while the structure between subsites +1 and +2 is critical for the glucose tolerance, the specific residues may not be identical across such enzymes.
[Mh] Termos MeSH primário: Agrobacterium tumefaciens/enzimologia
Glucose/química
beta-Glucosidase/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Sítios de Ligação
Celobiose/química
Celulose/química
Celulose 1,4-beta-Celobiosidase/química
Celulose 1,4-beta-Celobiosidase/genética
Hidrólise
Cinética
Especificidade por Substrato
beta-Glucosidase/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
16462-44-5 (Cellobiose); 9004-34-6 (Cellulose); EC 3.2.1.21 (beta-Glucosidase); EC 3.2.1.91 (Cellulose 1,4-beta-Cellobiosidase); IY9XDZ35W2 (Glucose)
[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:170907
[St] Status:MEDLINE
[do] DOI:10.1093/protein/gzx039


  2 / 694 MEDLINE  
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[PMID]:28873985
[Au] Autor:Badino SF; Bathke JK; Sørensen TH; Windahl MS; Jensen K; Peters GHJ; Borch K; Westh P
[Ad] Endereço:Research Unit for Functional Biomaterials, Department of Science and Environment, INM, Roskilde University, 1 Universitetsvej, Build. 28 C, DK-4000, Roskilde, Denmark.
[Ti] Título:The influence of different linker modifications on the catalytic activity and cellulose affinity of cellobiohydrolase Cel7A from Hypocrea jecorina.
[So] Source:Protein Eng Des Sel;30(7):495-501, 2017 Jul 01.
[Is] ISSN:1741-0134
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Various cellulases consist of a catalytic domain connected to a carbohydrate-binding module (CBM) by a flexible linker peptide. The linker if often strongly O-glycosylated and typically has a length of 20-50 amino acid residues. Functional roles, other than connecting the two folded domains, of the linker and its glycans, have been widely discussed, but experimental evidence remains sparse. One of the most studied cellulose degrading enzymes is the multi-domain cellobiohydrolase Cel7A from Hypocrea jecorina. Here, we designed variants of Cel7A with mutations in the linker region to elucidate the role of the linker. We found that moderate modification of the linker could result in significant changes in substrate affinity and catalytic efficacy. These changes were quite different for different linker variants. Thus, deletion of six residues near the catalytic domain had essentially no effects on enzyme function. Conversely, a substitution of four glycosylation sites near the middle of the linker reduced substrate affinity and increased maximal turnover. The observation of weaker binding provides some support of recent suggestions that linker glycans may be directly involved in substrate interactions. However, a variant with several inserted glycosylation sites near the CBM also showed lower affinity for the substrate compared to the wild-type, and we suggest that substrate interactions of the glycans depend on their exact location as well as other factors such as changes in structure and dynamics of the linker peptide.
[Mh] Termos MeSH primário: Catálise
Celulose 1,4-beta-Celobiosidase/química
Hypocrea/enzimologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos/genética
Celulase/química
Celulose/química
Celulose 1,4-beta-Celobiosidase/genética
Cinética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9004-34-6 (Cellulose); EC 3.2.1.4 (Cellulase); EC 3.2.1.91 (Cellulose 1,4-beta-Cellobiosidase)
[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:170907
[St] Status:MEDLINE
[do] DOI:10.1093/protein/gzx036


  3 / 694 MEDLINE  
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[PMID]:28860192
[Au] Autor:Goedegebuur F; Dankmeyer L; Gualfetti P; Karkehabadi S; Hansson H; Jana S; Huynh V; Kelemen BR; Kruithof P; Larenas EA; Teunissen PJM; Ståhlberg J; Payne CM; Mitchinson C; Sandgren M
[Ad] Endereço:From DuPont Industrial Biosciences, Archimedesweg 30, Leiden 2333CN, The Netherlands, frits.goedegebuur@dupont.com.
[Ti] Título:Improving the thermal stability of cellobiohydrolase Cel7A from by directed evolution.
[So] Source:J Biol Chem;292(42):17418-17430, 2017 Oct 20.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Secreted mixtures of cellulases are able to efficiently degrade cellulosic biomass to fermentable sugars at large, commercially relevant scales. Cel7A, cellobiohydrolase I, from glycoside hydrolase family 7, is the workhorse enzyme of the process. However, the thermal stability of Cel7A limits its use to processes where temperatures are no higher than 50 °C. Enhanced thermal stability is desirable to enable the use of higher processing temperatures and to improve the economic feasibility of industrial biomass conversion. Here, we enhanced the thermal stability of Cel7A through directed evolution. Sites with increased thermal stability properties were combined, and a Cel7A variant (FCA398) was obtained, which exhibited a 10.4 °C increase in and a 44-fold greater half-life compared with the wild-type enzyme. This Cel7A variant contains 18 mutated sites and is active under application conditions up to at least 75 °C. The X-ray crystal structure of the catalytic domain was determined at 2.1 Å resolution and showed that the effects of the mutations are local and do not introduce major backbone conformational changes. Molecular dynamics simulations revealed that the catalytic domain of wild-type Cel7A and the FCA398 variant exhibit similar behavior at 300 K, whereas at elevated temperature (475 and 525 K), the FCA398 variant fluctuates less and maintains more native contacts over time. Combining the structural and dynamic investigations, rationales were developed for the stabilizing effect at many of the mutated sites.
[Mh] Termos MeSH primário: Celulose 1,4-beta-Celobiosidase
Proteínas Fúngicas
Temperatura Alta
Hypocrea
[Mh] Termos MeSH secundário: Celulose 1,4-beta-Celobiosidase/química
Celulose 1,4-beta-Celobiosidase/genética
Cristalografia por Raios X
Evolução Molecular Direcionada
Estabilidade Enzimática/genética
Proteínas Fúngicas/química
Proteínas Fúngicas/genética
Hypocrea/enzimologia
Hypocrea/genética
Simulação de Dinâmica Molecular
Domínios Proteicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fungal Proteins); EC 3.2.1.91 (Cellulose 1,4-beta-Cellobiosidase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171027
[Lr] Data última revisão:
171027
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170902
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.803270


  4 / 694 MEDLINE  
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[PMID]:28847086
[Au] Autor:Yao L; Yang H; Yoo CG; Meng X; Li M; Pu Y; Ragauskas AJ; Sykes RW
[Ad] Endereço:School of Pulp & Paper Engineering, Hubei University of Technology, Wuhan 430068, China; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China; Department of Chemical and Biomolecular Engineering, The University of Tennessee, Knoxville,
[Ti] Título:Adsorption of cellobiohydrolases I onto lignin fractions from dilute acid pretreated Broussonetia papyrifera.
[So] Source:Bioresour Technol;244(Pt 1):957-962, 2017 Nov.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Broussonetia papyrifera, known as paper mulberry, is a potential feed stock for bioethanol production because of its cellulose-rich composition. Lignin in dilute acid pretreated Broussonetia papyrifera was fractionated to three different fractions, and their physiochemical properties were determined by FT-IR, GPC and NMR analyses. Different structural characteristics were observed from each lignin fraction. Cellobiohydrolases I (CBH) adsorption to each lignin was understood by the lignin properties. The results showed that aliphatic hydroxyl groups in lignin showed positive correlations with the maximum binding ability of CBH onto lignin samples. Also, the contents of phenolic compounds such as p-hydroxyphenyl benzoate (PB), syringyl (S) and guaiacyl (G) units in the lignin influenced their CBH binding.
[Mh] Termos MeSH primário: Broussonetia
Celulose 1,4-beta-Celobiosidase
[Mh] Termos MeSH secundário: Adsorção
Celulase
Hidrólise
Lignina
Espectroscopia de Infravermelho com Transformada de Fourier
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9005-53-2 (Lignin); EC 3.2.1.4 (Cellulase); EC 3.2.1.91 (Cellulose 1,4-beta-Cellobiosidase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171023
[Lr] Data última revisão:
171023
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170830
[St] Status:MEDLINE


  5 / 694 MEDLINE  
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[PMID]:28494147
[Au] Autor:Chaffey PK; Guan X; Chen C; Ruan Y; Wang X; Tran AH; Koelsch TN; Cui Q; Feng Y; Tan Z
[Ad] Endereço:Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado , Boulder, Colorado 80303, United States.
[Ti] Título:Structural Insight into the Stabilizing Effect of O-Glycosylation.
[So] Source:Biochemistry;56(23):2897-2906, 2017 Jun 13.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Protein glycosylation has been shown to have a variety of site-specific and glycan-specific effects, but so far, the molecular logic that leads to such observations has been elusive. Understanding the structural changes that occur and being able to correlate those with the physical properties of the glycopeptide are valuable steps toward being able to predict how specific glycosylation patterns will affect the stability of glycoproteins. By systematically comparing the structural features of the O-glycosylated carbohydrate-binding module of a Trichoderma reesei-derived Family 7 cellobiohydrolase, we were able to develop a better understanding of the influence of O-glycan structure on the molecule's physical stability. Our results indicate that the previously observed stabilizing effects of O-glycans come from the introduction of new bonding interactions to the structure and increased rigidity, while the decreased stability seemed to result from the impaired interactions and increased conformational flexibility. This type of knowledge provides a powerful and potentially general mechanism for improving the stability of proteins through glycoengineering.
[Mh] Termos MeSH primário: Celulose 1,4-beta-Celobiosidase/metabolismo
Proteínas Fúngicas/metabolismo
Glicoproteínas/metabolismo
Glicosídeo Hidrolases/metabolismo
Modelos Moleculares
Processamento de Proteína Pós-Traducional
Trichoderma/enzimologia
[Mh] Termos MeSH secundário: Substituição de Aminoácidos
Sítios de Ligação
Celulose 1,4-beta-Celobiosidase/química
Estabilidade Enzimática
Proteínas Fúngicas/química
Glicoproteínas/química
Glicosídeo Hidrolases/química
Glicosilação
Mutação
Ressonância Magnética Nuclear Biomolecular
Conformação Proteica
Dobramento de Proteína
Desdobramento de Proteína
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fungal Proteins); 0 (Glycoproteins); EC 3.2.1.- (Glycoside Hydrolases); EC 3.2.1.91 (Cellulose 1,4-beta-Cellobiosidase)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170706
[Lr] Data última revisão:
170706
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170512
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00195


  6 / 694 MEDLINE  
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[PMID]:28486197
[Au] Autor:Li Y; Zhang X; Xiong L; Mehmood MA; Zhao X; Bai F
[Ad] Endereço:State Key Laboratory of Microbial Metabolism & School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116023, China. Electronic address: yonghaoli@sjtu.edu.cn.
[Ti] Título:On-site cellulase production and efficient saccharification of corn stover employing cbh2 overexpressing Trichoderma reesei with novel induction system.
[So] Source:Bioresour Technol;238:643-649, 2017 Aug.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Although on-site cellulase production offers cost-effective saccharification of lignocellulosic biomass, low enzyme titer is still a barrier for achieving robustness. In the present study, a strain of T. reesei was developed for enhanced production of cellulase via overexpression of Cellobiohydrolase II. Furthermore, optimum enzyme production was achieved using a novel inducer mixture containing synthesized glucose-sophorose (MGD) and alkali pre-treated corn stover (APCS). Within 60h, a remarkably higher cellulase productivity and activity were achieved in the fed-batch fermentation using the optimized ratio of MGD and APCS in the inducer mixture, compared to those reported using cellulosic biomass as the sole inducer. After the enzyme production, APCS was added directly into the fermentation broth at 20% solid loading, which produced 122.5g/L glucose and 40.21g/L xylose, leading to the highest yield reported so far. The improved enzyme titers during on-site cellulase production would benefit cost-competitive saccharification of lignocellulosic biomass.
[Mh] Termos MeSH primário: Celulase
Trichoderma
Zea mays
[Mh] Termos MeSH secundário: Celulose 1,4-beta-Celobiosidase
Fermentação
Hidrólise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
EC 3.2.1.4 (Cellulase); EC 3.2.1.91 (Cellulose 1,4-beta-Cellobiosidase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171023
[Lr] Data última revisão:
171023
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170510
[St] Status:MEDLINE


  7 / 694 MEDLINE  
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[PMID]:28378498
[Au] Autor:Cao Y; Zheng F; Wang L; Zhao G; Chen G; Zhang W; Liu W
[Ad] Endereço:State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No. 27 Shanda South Road, Jinan, Shandong, 250100, P. R. China.
[Ti] Título:Rce1, a novel transcriptional repressor, regulates cellulase gene expression by antagonizing the transactivator Xyr1 in Trichoderma reesei.
[So] Source:Mol Microbiol;105(1):65-83, 2017 07.
[Is] ISSN:1365-2958
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Cellulase gene expression in the model cellulolytic fungus Trichoderma reesei is supposed to be controlled by an intricate regulatory network involving multiple transcription factors. Here, we identified a novel transcriptional repressor of cellulase gene expression, Rce1. Disruption of the rce1 gene not only facilitated the induced expression of cellulase genes but also led to a significant delay in terminating the induction process. However, Rce1 did not participate in Cre1-mediated catabolite repression. Electrophoretic mobility shift (EMSA) and DNase I footprinting assays in combination with chromatin immunoprecipitation (ChIP) demonstrated that Rce1 could bind directly to a cbh1 (cellobiohydrolase 1-encoding) gene promoter region containing a cluster of Xyr1 binding sites. Furthermore, competitive binding assays revealed that Rce1 antagonized Xyr1 from binding to the cbh1 promoter. These results indicate that intricate interactions exist between a variety of transcription factors to ensure tight and energy-efficient regulation of cellulase gene expression in T. reesei. This study also provides important clues regarding increased cellulase production in T. reesei.
[Mh] Termos MeSH primário: Celulase/genética
Trichoderma/genética
[Mh] Termos MeSH secundário: Sítios de Ligação/genética
Celulase/metabolismo
Celulose 1,4-beta-Celobiosidase/genética
Celulose 1,4-beta-Celobiosidase/metabolismo
Pegada de DNA/métodos
Proteínas Fúngicas/metabolismo
Expressão Gênica
Regulação Fúngica da Expressão Gênica/genética
Regiões Promotoras Genéticas/genética
Ligação Proteica/genética
Elementos Reguladores de Transcrição/genética
Transativadores/metabolismo
Fatores de Transcrição/metabolismo
Trichoderma/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Fungal Proteins); 0 (Trans-Activators); 0 (Transcription Factors); EC 3.2.1.4 (Cellulase); EC 3.2.1.91 (Cellulose 1,4-beta-Cellobiosidase)
[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:170406
[St] Status:MEDLINE
[do] DOI:10.1111/mmi.13685


  8 / 694 MEDLINE  
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[PMID]:28319763
[Au] Autor:Toyosawa Y; Ikeo M; Taneda D; Okino S
[Ad] Endereço:JGC Corporation, 2205, Narita-cho, Oarai-machi, Higashiibaraki-gun, Ibaraki Pref. 311-1313, Japan.
[Ti] Título:Quantitative analysis of adsorption and desorption behavior of individual cellulase components during the hydrolysis of lignocellulosic biomass with the addition of lysozyme.
[So] Source:Bioresour Technol;234:150-157, 2017 Jun.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The effect of non-catalytic protein addition on the adsorption/desorption behavior of individual cellulase components on/from substrates during the hydrolysis of microcrystalline cellulose and steam exploded sugarcane bagasse (SEB) were investigated. The addition of non-catalytic protein enhanced the enzymatic hydrolysis of SEB, but did not enhance the hydrolysis of microcrystalline cellulose. During the hydrolysis of SEB, adsorption of beta-glucosidase (BGL) was prevented in the presence of non-catalytic protein. Cellobiohydrolase I (CBH I) and endoglucanase I (EG I) desorbed from the substrate after temporary adsorption in the presence of non-catalytic protein during SEB hydrolysis. This suggested that reduction of the non-specific adsorption of cellulase components, CBH I, EG I, and BGL, on lignin in SEB led to the improving of enzymatic hydrolysis.
[Mh] Termos MeSH primário: Biomassa
Muramidase
[Mh] Termos MeSH secundário: Adsorção
Celulase/metabolismo
Celulose/química
Celulose 1,4-beta-Celobiosidase
Hidrólise
Lignina/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9004-34-6 (Cellulose); 9005-53-2 (Lignin); EC 3.2.1.17 (Muramidase); EC 3.2.1.4 (Cellulase); EC 3.2.1.91 (Cellulose 1,4-beta-Cellobiosidase)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170606
[Lr] Data última revisão:
170606
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170321
[St] Status:MEDLINE


  9 / 694 MEDLINE  
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[PMID]:28287708
[Au] Autor:Pereira A; Hoeger IC; Ferrer A; Rencoret J; Del Rio JC; Kruus K; Rahikainen J; Kellock M; Gutiérrez A; Rojas OJ
[Ad] Endereço:Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida de la Reina Mercedes, 10, E-41012 Sevilla, Spain.
[Ti] Título:Lignin Films from Spruce, Eucalyptus, and Wheat Straw Studied with Electroacoustic and Optical Sensors: Effect of Composition and Electrostatic Screening on Enzyme Binding.
[So] Source:Biomacromolecules;18(4):1322-1332, 2017 Apr 10.
[Is] ISSN:1526-4602
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Lignins were isolated from spruce, wheat straw, and eucalyptus by using the milled wood lignin (MWL) method. Functional groups and compositional analyses were assessed via 2D NMR and P NMR to realize their effect on enzyme binding. Films of the lignins were fabricated and ellipsometry, atomic force microscopy, and water contact angle measurements were used for their characterization and to reveal the changes upon enzyme adsorption. Moreover, lignin thin films were deposited on quartz crystal microgravimetry (QCM) and surface plasmon (SPR) resonance sensors and used to gain further insights into the lignin-cellulase interactions. For this purpose, a commercial multicomponent enzyme system and a monocomponent Trichoderma reesei exoglucanase (CBH-I) were considered. Strong enzyme adsorption was observed on the various lignins but compared to the multicomponent cellulases, CBH-I displayed lower surface affinity and higher binding reversibility. This resolved prevalent questions related to the affinity of this enzyme with lignin. Remarkably, a strong correlation between enzyme binding and the syringyl/guaiacyl (S/G) ratio was found for the lignins, which presented a similar hydroxyl group content ( P NMR): higher protein affinity was determined on isolated spruce lignin (99% G units), while the lowest adsorption occurred on isolated eucalyptus lignin (70% S units). The effect of electrostatic interactions in enzyme adsorption was investigated by SPR, which clearly indicated that the screening of charges allowed more extensive protein adsorption. Overall, this work furthers our understanding of lignin-cellulase interactions relevant to biomass that has been subjected to no or little pretreatment and highlights the widely contrasting effects of the nature of lignin, which gives guidance to improve lignocellulosic saccharification and related processes.
[Mh] Termos MeSH primário: Celulose 1,4-beta-Celobiosidase/química
Eucalyptus/química
Lignina/química
Picea/química
Triticum/química
[Mh] Termos MeSH secundário: Adsorção
Ligações de Hidrogênio
Interações Hidrofóbicas e Hidrofílicas
Lignina/isolamento & purificação
Microscopia de Força Atômica
Caules de Planta/química
Ligação Proteica
Técnicas de Microbalança de Cristal de Quartzo
Eletricidade Estática
Ressonância de Plasmônio de Superfície
Propriedades de Superfície
Trichoderma/enzimologia
Madeira/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9005-53-2 (Lignin); EC 3.2.1.91 (Cellulose 1,4-beta-Cellobiosidase)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171110
[Lr] Data última revisão:
171110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170314
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biomac.7b00071


  10 / 694 MEDLINE  
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[PMID]:28231536
[Au] Autor:Kellock M; Rahikainen J; Marjamaa K; Kruus K
[Ad] Endereço:VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, 02044 VTT, Finland. Electronic address: miriam.kellock@vtt.fi.
[Ti] Título:Lignin-derived inhibition of monocomponent cellulases and a xylanase in the hydrolysis of lignocellulosics.
[So] Source:Bioresour Technol;232:183-191, 2017 May.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Non-productive enzyme binding onto lignin is the major inhibitory mechanism, which reduces hydrolysis rates and yields and prevents efficient enzyme recycling in the hydrolysis of lignocellulosics. The detailed mechanisms of binding are still poorly understood. Enzyme-lignin interactions were investigated by comparing the structural properties and binding behaviour of fungal monocomponent enzymes, cellobiohydrolases TrCel7A and TrCel6A, endoglucanases TrCel7B and TrCel5A, a xylanase TrXyn11 and a ß-glucosidase AnCel3A, onto lignins isolated from steam pretreated spruce and wheat straw. The enzymes exhibited decreasing affinity onto lignin model films in the following order: TrCel7B>TrCel6A>TrCel5A>AnCel3A>TrCel7A>TrXyn11. As analysed in Avicel hydrolysis, TrCel6A and TrCel7B were most inhibited by lignin isolated from pretreated spruce. This could be partially explained by adsorption of the enzyme onto the lignin surface. Enzyme properties, such as enzyme surface charge, thermal stability or surface hydrophobicity could not alone explain the adsorption behaviour.
[Mh] Termos MeSH primário: Celulases/antagonistas & inibidores
Glicosídeo Hidrolases/antagonistas & inibidores
Lignina/farmacologia
[Mh] Termos MeSH secundário: Adsorção
Celulase/antagonistas & inibidores
Celulase/metabolismo
Celulases/metabolismo
Celulose/química
Celulose/metabolismo
Celulose 1,4-beta-Celobiosidase/antagonistas & inibidores
Celulose 1,4-beta-Celobiosidase/metabolismo
Glicosídeo Hidrolases/metabolismo
Hidrólise/efeitos dos fármacos
Interações Hidrofóbicas e Hidrofílicas
Lignina/química
Vapor
Triticum/metabolismo
beta-Glucosidase/antagonistas & inibidores
beta-Glucosidase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Steam); 9004-34-6 (Cellulose); 9005-53-2 (Lignin); EC 3.2.1.- (Cellulases); EC 3.2.1.- (Glycoside Hydrolases); EC 3.2.1.21 (beta-Glucosidase); EC 3.2.1.4 (Cellulase); EC 3.2.1.91 (Cellulose 1,4-beta-Cellobiosidase)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170512
[Lr] Data última revisão:
170512
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170224
[St] Status:MEDLINE



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