1
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Østby H, Hansen LD, Horn SJ, Eijsink VGH, Várnai A. Enzymatic processing of lignocellulosic biomass: principles, recent advances and perspectives. J Ind Microbiol Biotechnol 2020; 47:623-657. [PMID: 32840713 PMCID: PMC7658087 DOI: 10.1007/s10295-020-02301-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 07/30/2020] [Indexed: 02/06/2023]
Abstract
Efficient saccharification of lignocellulosic biomass requires concerted development of a pretreatment method, an enzyme cocktail and an enzymatic process, all of which are adapted to the feedstock. Recent years have shown great progress in most aspects of the overall process. In particular, increased insights into the contributions of a wide variety of cellulolytic and hemicellulolytic enzymes have improved the enzymatic processing step and brought down costs. Here, we review major pretreatment technologies and different enzyme process setups and present an in-depth discussion of the various enzyme types that are currently in use. We pay ample attention to the role of the recently discovered lytic polysaccharide monooxygenases (LPMOs), which have led to renewed interest in the role of redox enzyme systems in lignocellulose processing. Better understanding of the interplay between the various enzyme types, as they may occur in a commercial enzyme cocktail, is likely key to further process improvements.
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Affiliation(s)
- Heidi Østby
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Line Degn Hansen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Svein J Horn
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Anikó Várnai
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway.
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2
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Wantuch PL, Jella S, Duke JA, Mousa JJ, Henrissat B, Glushka J, Avci FY. Characterization of the β-glucuronidase Pn3Pase as the founding member of glycoside hydrolase family GH169. Glycobiology 2020; 31:266-274. [PMID: 32810871 DOI: 10.1093/glycob/cwaa070] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 07/20/2020] [Accepted: 07/21/2020] [Indexed: 12/25/2022] Open
Abstract
Paenibacillus sp. 32352 is a soil-dwelling bacterium capable of producing an enzyme, Pn3Pase that degrades the capsular polysaccharide of Streptococcus pneumoniae serotype 3 (Pn3P). Recent reports on Pn3Pase have demonstrated its initial characterization and potential for protection against highly virulent S. pneumoniae serotype 3 infections. Initial experiments revealed this enzyme functions as an exo-β1,4-glucuronidase cleaving the β(1,4) linkage between glucuronic acid and glucose. However, the catalytic mechanism of this enzyme is still unknown. Here, we report the detailed biochemical analysis of Pn3Pase. Pn3Pase shows no significant sequence similarity to known glycoside hydrolase (GH) families, thus this novel enzyme establishes a new carbohydrate-active enzyme (CAZy) GH family. Site-directed mutagenesis studies revealed two catalytic residues along with truncation mutants defining essential domains for function. Pn3Pase and its mutants were screened for activity, substrate binding and kinetics. Additionally, nuclear magnetic resonance spectroscopy analysis revealed that Pn3Pase acts through a retaining mechanism. This study exhibits Pn3Pase activity at the structural and mechanistic level to establish the new CAZy GH family GH169 belonging to the large GH-A clan. This study will also serve toward generating Pn3Pase derivatives with optimal activity and pharmacokinetics aiding in the use of Pn3Pase as a novel therapeutic approach against type 3 S. pneumoniae infections.
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Affiliation(s)
- Paeton L Wantuch
- Department of Biochemistry & Molecular Biology, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA.,Center for Molecular Medicine, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA
| | - Satya Jella
- Center for Molecular Medicine, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA
| | - Jeremy A Duke
- Department of Biochemistry & Molecular Biology, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA.,Center for Molecular Medicine, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA
| | - Jarrod J Mousa
- Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, 501 D.W. Brooks Dr Athens, Athens GA 30602, USA.,Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, 501 D.W. Brooks Dr Athens, Athens GA 30602, USA
| | - Bernard Henrissat
- Architecture et Fonction des Macromolécules Biologiques, CNRS, Aix-Marseille University, 163 Avenue de Luminy, Parc Scientifique et Technologique de Luminy, 13288 Marseille, France.,USC1408 Architecture et Fonction des Macromolécules Biologiques, Institut National de la Recherche Agronomique, 163 Avenue de Luminy, Parc Scientifique et Technologique de Luminy, 13288 Marseille, France.,Department of Biological Sciences, King Abdulaziz University, Al Jami`ah, Jeddah, 23218, Saudi Arabia
| | - John Glushka
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Rd, Athens GA 30602, USA
| | - Fikri Y Avci
- Department of Biochemistry & Molecular Biology, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA.,Center for Molecular Medicine, University of Georgia, 325 Riverbend Rd, Athens GA 30602, USA
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3
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Christensen SJ, Badino SF, Cavaleiro AM, Borch K, Westh P. Functional analysis of chimeric TrCel6A enzymes with different carbohydrate binding modules. Protein Eng Des Sel 2020; 32:401-409. [PMID: 32100026 DOI: 10.1093/protein/gzaa003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 01/10/2019] [Accepted: 01/13/2019] [Indexed: 11/14/2022] Open
Abstract
The glycoside hydrolase (GH) family 6 is an important group of enzymes that constitute an essential part of industrial enzyme cocktails used to convert lignocellulose into fermentable sugars. In nature, enzymes from this family often have a carbohydrate binding module (CBM) from the CBM family 1. These modules are known to promote adsorption to the cellulose surface and influence enzymatic activity. Here, we have investigated the functional diversity of CBMs found within the GH6 family. This was done by constructing five chimeric enzymes based on the model enzyme, TrCel6A, from the soft-rot fungus Trichoderma reesei. The natural CBM of this enzyme was exchanged with CBMs from other GH6 enzymes originating from different cellulose degrading fungi. The chimeric enzymes were expressed in the same host and investigated in adsorption and quasi-steady-state kinetic experiments. Our results quantified functional differences of these phylogenetically distant binding modules. Thus, the partitioning coefficient for substrate binding varied 4-fold, while the maximal turnover (kcat) showed a 2-fold difference. The wild-type enzyme showed the highest cellulose affinity on all tested substrates and the highest catalytic turnover. The CBM from Serendipita indica strongly promoted the enzyme's ability to form productive complexes with sites on the substrate surface but showed lower turnover of the complex. We conclude that the CBM plays an important role for the functional differences between GH6 wild-type enzymes.
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Affiliation(s)
- Stefan Jarl Christensen
- Research Unit for Functional Biomaterials, Department of Science and Environment, Roskilde University, building 28B, DK-4000, Roskilde, Denmark
| | - Silke Flindt Badino
- Research Unit for Functional Biomaterials, Department of Science and Environment, Roskilde University, building 28B, DK-4000, Roskilde, Denmark
| | - Ana Mafalda Cavaleiro
- Research Unit for Functional Biomaterials, Department of Science and Environment, Roskilde University, building 28B, DK-4000, Roskilde, Denmark.,Novozymes A/S, Department of Enzyme Discovery, Rævehøjvej 32A, DK-2800 Kgs. Lyngby, Denmark
| | - Kim Borch
- Novozymes A/S, Department of Enzyme Discovery, Rævehøjvej 32A, DK-2800 Kgs. Lyngby, Denmark
| | - Peter Westh
- Department of Biotechnology and Biomedicine, Technical University of Denmark, building 224, DK-2800, Kgs. Lyngby, Denmark
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4
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Voutilainen S, Paananen A, Lille M, Linder MB. Modular protein architectures for pH-dependent interactions and switchable assembly of nanocellulose. Int J Biol Macromol 2019; 137:270-276. [PMID: 31260762 DOI: 10.1016/j.ijbiomac.2019.06.227] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/17/2019] [Accepted: 06/28/2019] [Indexed: 11/27/2022]
Abstract
Protein engineering shows a wide range of possibilities for designing properties in novel materials. Following inspiration from natural systems we have studied how combinations or duplications of protein modules can be used to engineer their interactions and achieve functional properties. Here we used cellulose binding modules (CBM) coupled to spider silk N-terminal domains that dimerize in a pH-sensitive manner. We showed how the pH-sensitive switching into dimers affected cellulose binding affinity in relation to covalent coupling between CBMs. Finally, we showed how the pH-sensitive coupling could be used to assemble cellulose nanofibers in a dynamic pH-dependent way. The work shows how novel proteins can be designed by linking functional domains from widely different sources and thereby achieve new functions in the self-assembly of nanoscale materials.
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Affiliation(s)
- Sanni Voutilainen
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, Box 16100, 00076, Aalto, Espoo, Finland; VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, 02044 VTT Espoo, Finland
| | - Arja Paananen
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, 02044 VTT Espoo, Finland
| | - Martina Lille
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, 02044 VTT Espoo, Finland
| | - Markus B Linder
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, Box 16100, 00076, Aalto, Espoo, Finland.
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5
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Carbohydrate binding modules enhance cellulose enzymatic hydrolysis by increasing access of cellulases to the substrate. Carbohydr Polym 2019; 211:57-68. [DOI: 10.1016/j.carbpol.2019.01.108] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 01/24/2019] [Accepted: 01/30/2019] [Indexed: 11/22/2022]
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6
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Danneels B, Tanghe M, Desmet T. Structural Features on the Substrate-Binding Surface of Fungal Lytic Polysaccharide Monooxygenases Determine Their Oxidative Regioselectivity. Biotechnol J 2018; 14:e1800211. [PMID: 30238672 DOI: 10.1002/biot.201800211] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 08/15/2018] [Indexed: 01/15/2023]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that oxidatively cleave many of nature's most recalcitrant polysaccharides by acting on the C1- and/or C4-carbon of the glycosidic bond. Here, the results of an extensive mutagenesis study on three LPMO representatives, Phanerochaete chrysosporium LPMO9D (C1-oxidizer), Neurospora crassa LPMO9C (C4), and Hypocrea jecorina LPMO9A (C1/C4), are reported. Using a previously published indicator diagram, the authors demonstrate that several structural determinants of LPMOs play an important role in their oxidative regioselectivity. N-glycan removal and alterations of the aromatic residues on the substrate-binding surface are shown to alter C1/C4-oxidation ratios. Removing the carbohydrate binding module (CBM) is found not to alter the regioselectivity of HjLPMO9A, although the effect of mutational changes is shown to increase in a CBM-free context. The accessibility to the solvent-exposed axial position of the copper-site reveales not to be a major regioselectivity indicator, at least not in PcLPMO9D. Interestingly, a HjLPMO9A variant lacking two surface exposed aromatic residues combines decreased binding capacity with a 22% increase in synergetic efficiency. Similarly to recent LPMO10 findings, our results suggest a complex matrix of surface-interactions that enables LPMO9s not only to bind their substrate, but also to accurately direct their oxidative force.
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Affiliation(s)
- Barbara Danneels
- Department of Biotechnology, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Magali Tanghe
- Department of Biotechnology, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Tom Desmet
- Department of Biotechnology, Ghent University, Coupure links 653, 9000 Ghent, Belgium
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7
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Fang W, Paananen A, Vitikainen M, Koskela S, Westerholm-Parvinen A, Joensuu JJ, Landowski CP, Penttilä M, Linder MB, Laaksonen P. Elastic and pH-Responsive Hybrid Interfaces Created with Engineered Resilin and Nanocellulose. Biomacromolecules 2017; 18:1866-1873. [PMID: 28440631 DOI: 10.1021/acs.biomac.7b00294] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We investigated how a genetically engineered resilin fusion protein modifies cellulose surfaces. We characterized the pH-responsive behavior of a resilin-like polypeptide (RLP) having terminal cellulose binding modules (CBM) and showed its binding to cellulose nanofibrils (CNF). Characterization of the resilin fusion protein at different pHs revealed substantial conformational changes of the protein, which were observed as swelling and contraction of the protein layer bound to the nanocellulose surface. In addition, we showed that employment of the modified resilin in cellulose hydrogel and nanopaper increased their modulus of stiffness through a cross-linking effect.
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Affiliation(s)
- Wenwen Fang
- Department of Bioproducts and Biosystems, Aalto University , Espoo, FI-00076 Aalto, Finland
| | - Arja Paananen
- VTT Technical Research Centre of Finland Ltd., Espoo, FI-02044 VTT, Finland
| | - Marika Vitikainen
- VTT Technical Research Centre of Finland Ltd., Espoo, FI-02044 VTT, Finland
| | - Salla Koskela
- VTT Technical Research Centre of Finland Ltd., Espoo, FI-02044 VTT, Finland
| | | | - Jussi J Joensuu
- VTT Technical Research Centre of Finland Ltd., Espoo, FI-02044 VTT, Finland
| | | | - Merja Penttilä
- VTT Technical Research Centre of Finland Ltd., Espoo, FI-02044 VTT, Finland
| | - Markus B Linder
- Department of Bioproducts and Biosystems, Aalto University , Espoo, FI-00076 Aalto, Finland
| | - Päivi Laaksonen
- Department of Bioproducts and Biosystems, Aalto University , Espoo, FI-00076 Aalto, Finland
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8
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Arola S, Linder MB. Binding of cellulose binding modules reveal differences between cellulose substrates. Sci Rep 2016; 6:35358. [PMID: 27748440 PMCID: PMC5066208 DOI: 10.1038/srep35358] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 09/28/2016] [Indexed: 11/20/2022] Open
Abstract
The interaction between cellulase enzymes and their substrates is of central importance to several technological and scientific challenges. Here we report that the binding of cellulose binding modules (CBM) from Trichoderma reesei cellulases Cel6A and Cel7A show a major difference in how they interact with substrates originating from wood compared to bacterial cellulose. We found that the CBM from TrCel7A recognizes the two substrates differently and as a consequence shows an unexpected way of binding. We show that the substrate has a large impact on the exchange rate of the studied CBM, and moreover, CBM-TrCel7A seems to have an additional mode of binding on wood derived cellulose but not on cellulose originating from bacterial source. This mode is not seen in double CBM (DCBM) constructs comprising both CBM-TrCel7A and CBM-TrCel6A. The linker length of DCBMs affects the binding properties, and slows down the exchange rates of the proteins and thus, can be used to analyze the differences between the single CBM. These results have impact on the cellulase research and offer new understanding on how these industrially relevant enzymes act.
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Affiliation(s)
- Suvi Arola
- School of Science, Aalto University, P. O. Box 11100, FI-00076, Aalto, Finland
- School of Chemical Technology, Aalto University, P.O. Box 16100, FI-00076, Aalto, Finland
- VTT, Technical Research Centre of Finland, Bio and process technology, P.O.Box 1000, FIN–02044 VTT, Finland
| | - Markus B. Linder
- School of Chemical Technology, Aalto University, P.O. Box 16100, FI-00076, Aalto, Finland
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9
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Nakamura A, Tasaki T, Ishiwata D, Yamamoto M, Okuni Y, Visootsat A, Maximilien M, Noji H, Uchiyama T, Samejima M, Igarashi K, Iino R. Single-molecule Imaging Analysis of Binding, Processive Movement, and Dissociation of Cellobiohydrolase Trichoderma reesei Cel6A and Its Domains on Crystalline Cellulose. J Biol Chem 2016; 291:22404-22413. [PMID: 27609516 DOI: 10.1074/jbc.m116.752048] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 08/24/2016] [Indexed: 11/06/2022] Open
Abstract
Trichoderma reesei Cel6A (TrCel6A) is a cellobiohydrolase that hydrolyzes crystalline cellulose into cellobiose. Here we directly observed the reaction cycle (binding, surface movement, and dissociation) of single-molecule intact TrCel6A, isolated catalytic domain (CD), cellulose-binding module (CBM), and CBM and linker (CBM-linker) on crystalline cellulose Iα The CBM-linker showed a binding rate constant almost half that of intact TrCel6A, whereas those of the CD and CBM were only one-tenth of intact TrCel6A. These results indicate that the glycosylated linker region largely contributes to initial binding on crystalline cellulose. After binding, all samples showed slow and fast dissociations, likely caused by the two different bound states due to the heterogeneity of cellulose surface. The CBM showed much higher specificity to the high affinity site than to the low affinity site, whereas the CD did not, suggesting that the CBM leads the CD to the hydrophobic surface of crystalline cellulose. On the cellulose surface, intact molecules showed slow processive movements (8.8 ± 5.5 nm/s) and fast diffusional movements (30-40 nm/s), whereas the CBM-Linker, CD, and a catalytically inactive full-length mutant showed only fast diffusional movements. These results suggest that both direct binding and surface diffusion contribute to searching of the hydrolysable point of cellulose chains. The duration time constant for the processive movement was 7.7 s, and processivity was estimated as 68 ± 42. Our results reveal the role of each domain in the elementary steps of the reaction cycle and provide the first direct evidence of the processive movement of TrCel6A on crystalline cellulose.
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Affiliation(s)
- Akihiko Nakamura
- From the Okazaki Institute for Integrative Bioscience and.,the Department of Functional Molecular Science, School of Physical Sciences, Graduate University for Advanced Studies (SOKENDAI), Kanagawa 240-0193, Japan
| | - Tomoyuki Tasaki
- the Department of Applied Chemistry, Graduate School of Engineering, University of Tokyo, Tokyo 113-8656, Japan
| | - Daiki Ishiwata
- From the Okazaki Institute for Integrative Bioscience and
| | | | - Yasuko Okuni
- From the Okazaki Institute for Integrative Bioscience and
| | - Akasit Visootsat
- the Department of Biochemistry, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand
| | - Morice Maximilien
- the National Chemical Engineering Institute in Paris, Paris 75005, France
| | - Hiroyuki Noji
- the Department of Applied Chemistry, Graduate School of Engineering, University of Tokyo, Tokyo 113-8656, Japan
| | - Taku Uchiyama
- the Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-8657, Japan, and
| | - Masahiro Samejima
- the Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-8657, Japan, and
| | - Kiyohiko Igarashi
- the Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-8657, Japan, and.,the VTT Technical Research Centre of Finland, Espoo FI-02044 VTT, Finland
| | - Ryota Iino
- From the Okazaki Institute for Integrative Bioscience and .,the Department of Functional Molecular Science, School of Physical Sciences, Graduate University for Advanced Studies (SOKENDAI), Kanagawa 240-0193, Japan.,Institute for Molecular Science, National Institutes of Natural Sciences, Aichi 444-8787, Japan
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10
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Martinez T, Texier H, Nahoum V, Lafitte C, Cioci G, Heux L, Dumas B, O’Donohue M, Gaulin E, Dumon C. Probing the Functions of Carbohydrate Binding Modules in the CBEL Protein from the Oomycete Phytophthora parasitica. PLoS One 2015; 10:e0137481. [PMID: 26390127 PMCID: PMC4577117 DOI: 10.1371/journal.pone.0137481] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/17/2015] [Indexed: 11/29/2022] Open
Abstract
Oomycetes are microorganisms that are distantly related to true fungi and many members of this phylum are major plant pathogens. Oomycetes express proteins that are able to interact with plant cell wall polysaccharides, such as cellulose. This interaction is thought to be mediated by carbohydrate-binding modules that are classified into CBM family 1 in the CAZy database. In this study, the two CBMs (1–1 and 1–2) that form part of the cell wall glycoprotein, CBEL, from Phytophthora parasitica have been submitted to detailed characterization, first to better quantify their interaction with cellulose and second to determine whether these CBMs can be useful for biotechnological applications, such as biomass hydrolysis. A variety of biophysical techniques were used to study the interaction of the CBMs with various substrates and the data obtained indicate that CBEL’s CBM1-1 exhibits much greater cellulose binding ability than CBM1-2. Engineering of the family 11 xylanase from Talaromyces versatilis (TvXynB), an enzyme that naturally bears a fungal family 1 CBM, has produced two variants. The first one lacks its native CBM, whereas the second contains the CBEL CBM1-1. The study of these enzymes has revealed that wild type TvXynB binds to cellulose, via its CBM1, and that the substitution of its CBM by oomycetal CBM1-1 does not affect its activity on wheat straw. However, intriguingly the addition of CBEL during the hydrolysis of wheat straw actually potentiates the action of TvXynB variant lacking a CBM1. This suggests that the potentiating effect of CBM1-1 might not require the formation of a covalent linkage to TvXynB.
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Affiliation(s)
- Thomas Martinez
- Université Toulouse 3, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, F-31326, Castanet-Tolosan, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, F-31326, Castanet-Tolosan, France
- Université de Toulouse; INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France
- CNRS, UMR5504, F-31400 Toulouse, France
- INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France
| | - Hélène Texier
- Université de Toulouse; INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France
- CNRS, UMR5504, F-31400 Toulouse, France
- INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France
- Cinabio ADISSEO France SAS, Hall Gilbert Durand 3, 135 avenue de Rangueil, 31077 Toulouse, France
| | - Virginie Nahoum
- Université de Toulouse, UPS, IPBS, Toulouse, F-31077, France
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Centre National de la Recherche Scientifique (CNRS), Toulouse, F-31077, France
| | - Claude Lafitte
- Université Toulouse 3, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, F-31326, Castanet-Tolosan, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, F-31326, Castanet-Tolosan, France
| | - Gianluca Cioci
- Université de Toulouse; INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France
- CNRS, UMR5504, F-31400 Toulouse, France
- INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France
| | | | - Bernard Dumas
- Université Toulouse 3, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, F-31326, Castanet-Tolosan, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, F-31326, Castanet-Tolosan, France
| | - Michael O’Donohue
- Université de Toulouse; INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France
- CNRS, UMR5504, F-31400 Toulouse, France
- INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France
| | - Elodie Gaulin
- Université Toulouse 3, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, F-31326, Castanet-Tolosan, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, F-31326, Castanet-Tolosan, France
| | - Claire Dumon
- Université de Toulouse; INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France
- CNRS, UMR5504, F-31400 Toulouse, France
- INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France
- * E-mail:
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11
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Happs RM, Guan X, Resch MG, Davis MF, Beckham GT, Tan Z, Crowley MF. O-glycosylation effects on family 1 carbohydrate-binding module solution structures. FEBS J 2015; 282:4341-56. [PMID: 26307003 DOI: 10.1111/febs.13500] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 08/18/2015] [Accepted: 08/21/2015] [Indexed: 01/20/2023]
Abstract
UNLABELLED Family 1 carbohydrate-binding modules (CBMs) are ubiquitous components of multimodular fungal enzymes that degrade plant cell wall polysaccharides and bind specifically to cellulose. Native glycosylation of family 1 CBMs has been shown to substantially impact multiple physical properties, including thermal and proteolytic stability and cellulose binding affinity. To gain molecular insights into the changes in CBM properties upon glycosylation, solution structures of two glycoforms of a Trichoderma reesei family 1 CBM were studied by NMR spectroscopy: a glycosylated family 1 CBM with a mannose group attached to both Thr1 and Ser3 and a second family 1 CBM with single mannose groups attached to Thr1, Ser3 and Ser14. The structures clearly reveal that monosaccharides at both Ser3 and Ser14 on family 1 CBMs present additional cellulose binding platforms, similar to well-characterized aromatic residues at the binding interface, which align to the cellulose surface. These results are in agreement with previous experimental work demonstrating that glycans at Ser3 and Ser14 impart significant improvements in binding affinity. Additionally, detailed analysis of the NMR structures and molecular simulations indicates that the protein backbone of the CBM is not significantly altered by attachment of monosaccharides, and that the mannose attached to Ser14 may be more flexible than the mannose at Ser3. Overall, the present study reveals how family 1 CBM structures are affected by covalent attachment of monosaccharides, which are likely important post-translational modifications of these common subdomains of fungal plant cell wall degrading enzymes. DATABASE Structural data have been deposited in the RCSB Protein Data Bank (PDB codes: 2MWJ and 2MWK) and the BioMagRes Bank (BMRB codes: 25331 and 25332) for CBM_M2 and CBM_M3, respectively.
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Affiliation(s)
- Renee M Happs
- National Renewable Energy Laboratory, National Bioenergy Center, Golden, CO, USA
| | - Xiaoyang Guan
- Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, CO, USA
| | - Michael G Resch
- National Renewable Energy Laboratory, National Bioenergy Center, Golden, CO, USA
| | - Mark F Davis
- National Renewable Energy Laboratory, National Bioenergy Center, Golden, CO, USA
| | - Gregg T Beckham
- National Renewable Energy Laboratory, National Bioenergy Center, Golden, CO, USA
| | - Zhongping Tan
- Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, CO, USA
| | - Michael F Crowley
- National Renewable Energy Laboratory, Biosciences Center, Golden, CO, USA
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12
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Hamid SBA, Islam MM, Das R. Cellulase biocatalysis: key influencing factors and mode of action. CELLULOSE 2015; 22:2157-2182. [DOI: 10.1007/s10570-015-0672-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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13
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Payne CM, Knott BC, Mayes HB, Hansson H, Himmel ME, Sandgren M, Ståhlberg J, Beckham GT. Fungal Cellulases. Chem Rev 2015; 115:1308-448. [DOI: 10.1021/cr500351c] [Citation(s) in RCA: 533] [Impact Index Per Article: 59.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Christina M. Payne
- Department
of Chemical and Materials Engineering and Center for Computational
Sciences, University of Kentucky, 177 F. Paul Anderson Tower, Lexington, Kentucky 40506, United States
| | - Brandon C. Knott
- National
Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver
West Parkway, Golden, Colorado 80401, United States
| | - Heather B. Mayes
- Department
of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Henrik Hansson
- Department
of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala BioCenter, Almas allé 5, SE-75651 Uppsala, Sweden
| | - Michael E. Himmel
- Biosciences
Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, United States
| | - Mats Sandgren
- Department
of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala BioCenter, Almas allé 5, SE-75651 Uppsala, Sweden
| | - Jerry Ståhlberg
- Department
of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala BioCenter, Almas allé 5, SE-75651 Uppsala, Sweden
| | - Gregg T. Beckham
- National
Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver
West Parkway, Golden, Colorado 80401, United States
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14
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Nishijima H, Nozaki K, Mizuno M, Arai T, Amano Y. Extra tyrosine in the carbohydrate-binding module of Irpex lacteus Xyn10B enhances its cellulose-binding ability. Biosci Biotechnol Biochem 2015; 79:738-46. [PMID: 25560084 DOI: 10.1080/09168451.2014.996203] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The xylanase (Xyn10B) that strongly adsorbs on microcrystalline cellulose was isolated from Driselase. The Xyn10B contains a Carbohydrate-binding module family 1 (CBM1) (IrpCBMXyn10B) at N-terminus. The canonical essential aromatic residues required for cellulose binding were conserved in IrpCBMXyn10B; however, its adsorption ability was markedly higher than that typically observed for the CBM1 of an endoglucanase from Trametes hirsuta (ThCBMEG1). An analysis of the CBM-GFP fusion proteins revealed that the binding capacity to cellulose (7.8 μmol/g) and distribution coefficient (2.0 L/μmol) of IrpCBMXyn10B-GFP were twofold higher than those of ThCBMEG1-GFP (3.4 μmol/g and 1.2 L/μmol, respectively), used as a reference structure. Besides the canonical aromatic residues (W24-Y50-Y51) of typical CBM1-containing proteins, IrpCBMXyn10B had an additional aromatic residue (Y52). The mutation of Y52 to Ser (IrpCBMY52S-GFP) reduced these adsorption parameters to 4.4 μmol/g and 1.5 L/μmol, which were similar to those of ThCBMEG1-GFP. These results indicate that Y52 plays a crucial role in strong cellulose binding.
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Affiliation(s)
- Hiroto Nishijima
- a Department of Bioscience & Textile Technology, Interdisciplinary Graduate School of Science and Technology , Shinshu University , Nagano , Japan
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15
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Pellegrini VOA, Lei N, Kyasaram M, Olsen JP, Badino SF, Windahl MS, Colussi F, Cruys-Bagger N, Borch K, Westh P. Reversibility of substrate adsorption for the cellulases Cel7A, Cel6A, and Cel7B from Hypocrea jecorina. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:12602-12609. [PMID: 25322452 DOI: 10.1021/la5024423] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Adsorption of cellulases on the cellulose surface is an integral part of the catalytic mechanism, and a detailed description of the adsorption process is therefore required for a fundamental understanding of this industrially important class of enzymes. However, the mode of adsorption has proven intricate, and several key questions remain open. Perhaps most notably it is not clear whether the adsorbed enzyme is in dynamic equilibrium with the free population or irreversibly associated with no or slow dissociation. To address this, we have systematically investigated adsorption reversibility for two cellobiohydrolases (Cel7A and Cel6A) and one endoglucanase (Cel7B) on four types of pure cellulose substrates. Specifically, we monitored dilution-induced release of adsorbed enzyme in samples that had previously been brought to a steady state (constant concentration of free enzyme). In simple dilution experiments (without centrifugation), the results consistently showed full reversibility. In contrast to this, resuspension of enzyme-substrate pellets separated by centrifugation showed extensive irreversibility. We conclude that these enzymes are in a dynamic equilibrium between free and adsorbed states but suggest that changes in the physical properties of cellulose caused by compaction of the pellet hampers subsequent release of adsorbed enzyme. This latter effect may be pertinent to both previous controversies in the literature on adsorption reversibility and the development of enzyme recycling protocols in the biomass industry.
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Affiliation(s)
- Vanessa O A Pellegrini
- Research Unit for Functional Biomaterials, NSM, Roskilde University , 1 Universitetsvej, Build. 18.1, DK-4000 Roskilde, Denmark
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16
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Shang BZ, Chu JW. Kinetic Modeling at Single-Molecule Resolution Elucidates the Mechanisms of Cellulase Synergy. ACS Catal 2014. [DOI: 10.1021/cs500126q] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Barry Z. Shang
- Department
of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Jhih-Wei Chu
- Department
of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
- Department
of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan, ROC
- Institute
of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan, ROC
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17
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Zhao J, Chen H. Stimulation of Cellulases by Small Phenolic Compounds in Pretreated Stover. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:3223-3229. [PMID: 24564197 DOI: 10.1021/jf405046m] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The effect of small phenolic compounds in pretreated stover on celluase activity is crucial but has not yet been fully elucidated. This work investigated the effects of both phenolic acid and phenolic aldehyde on cellulase activity. The model substances of small phenolic compounds identified in steam exploded corn stover were used to examine their individual effects on cellulase activity. It was found that phenolic aldehyde significantly inhibited cellulase activity at 0.05-8 g/L. However, phenolic acids might have a concentration-dependent effect on cellulase activity: significant inhibition at 0.05 g/L and slight stimulation at 2-4 g/L. Small phenolic compounds mixture might also have a concentration-dependent effect on cellulase activity: significant stimulation at 2-8 g/L and slight inhibition at 0.05-1 g/L. The small phenolic compounds in pretreated stover were proven to be able to significantly stimulate enzymatic hydrolysis of stover. On the basis of these results, it is proposed that the concentration-dependent effects of small phenolic compounds on cellulase activity should be considered while removing them after pretreatment.
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Affiliation(s)
- Junying Zhao
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences , Beijing 100190, China
- Graduate University of Chinese Academy of Sciences , Beijing 100049, China
| | - Hongzhang Chen
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences , Beijing 100190, China
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18
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Hama S, Nakano K, Onodera K, Nakamura M, Noda H, Kondo A. Saccharification behavior of cellulose acetate during enzymatic processing for microbial ethanol production. BIORESOURCE TECHNOLOGY 2014; 157:1-5. [PMID: 24514162 DOI: 10.1016/j.biortech.2014.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 12/29/2013] [Accepted: 01/02/2014] [Indexed: 06/03/2023]
Abstract
This study was conducted to realize the potential application of cellulose acetate to enzymatic processing, followed by microbial ethanol fermentation. To eliminate the effect of steric hindrance of acetyl groups on the action of cellulase, cellulose acetate was subjected to deacetylation in the presence of 1N sodium hydroxide and a mixture of methanol/acetone, yielding 88.8-98.6% at 5-20% substrate loadings during a 48h saccharification at 50°C. Ethanol fermentation using Saccharomyces cerevisiae attained a high yield of 92.3% from the initial glucose concentration of 44.2g/L; however, a low saccharification yield was obtained at 35°C, decreasing efficiency during simultaneous saccharification and fermentation (SSF). Presaccharification at 50°C prior to SSF without increasing the total process time attained the ethanol titers of 19.8g/L (5% substrate), 38.0g/L (10% substrate), 55.9g/L (15% substrate), and 70.9g/L (20% substrate), which show a 12.0-16.2% improvement in ethanol yield.
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Affiliation(s)
- Shinji Hama
- Bio-energy Corporation, Research and Development Laboratory, 2-9-7 Minaminanamatsu, Amagasaki 660-0053, Japan
| | - Kohsuke Nakano
- Bio-energy Corporation, Research and Development Laboratory, 2-9-7 Minaminanamatsu, Amagasaki 660-0053, Japan
| | - Kaoru Onodera
- Bio-energy Corporation, Research and Development Laboratory, 2-9-7 Minaminanamatsu, Amagasaki 660-0053, Japan
| | - Masashi Nakamura
- Bio-energy Corporation, Research and Development Laboratory, 2-9-7 Minaminanamatsu, Amagasaki 660-0053, Japan
| | - Hideo Noda
- Bio-energy Corporation, Research and Development Laboratory, 2-9-7 Minaminanamatsu, Amagasaki 660-0053, Japan
| | - Akihiko Kondo
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan.
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19
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Wahlström R, Rahikainen J, Kruus K, Suurnäkki A. Cellulose hydrolysis and binding with Trichoderma reesei Cel5A and Cel7A and their core domains in ionic liquid solutions. Biotechnol Bioeng 2013; 111:726-33. [PMID: 24258388 DOI: 10.1002/bit.25144] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 09/26/2013] [Accepted: 10/28/2013] [Indexed: 11/06/2022]
Abstract
Ionic liquids (ILs) dissolve lignocellulosic biomass and have a high potential as pretreatment prior to total enzymatic hydrolysis. ILs are, however, known to inactivate cellulases. In this article, enzymatic hydrolysis of microcrystalline cellulose (MCC) and enzyme binding onto the cellulosic substrate were studied in the presence of cellulose-dissolving ILs. Two different ILs, 1,3-dimethylimidazolium dimethylphosphate ([DMIM]DMP) and 1-ethyl-3-methylimidazolium acetate ([EMIM]AcO), and two monocomponent cellulases, Trichoderma reesei cellobiohydrolase Cel7A and endoglucanase Cel5A, were used in the study. The role and IL sensitivity of the carbohydrate-binding module (CBM) were studied by performing hydrolysis and binding experiments with both the intact cellulases, and their respective core domains (CDs). Based on hydrolysis yields and substrate binding experiments for the intact enzymes and their CDs in the presence of ILs, the function of the CBM appeared to be very IL sensitive. Binding data suggested that the CBM was more important for the substrate binding of endoglucanase Cel5A than for the binding of cellobiohydrolase Cel7A. The CD of Cel7A was able to bind well to cellulose even without a CBM, whereas Cel5A CD had very low binding affinity. Hydrolysis also occurred with Cel5A CD even if this protein had very low binding affinity in all the studied matrices. Binding and hydrolysis were less affected by the studied ILs for Cel7A than for Cel5A. To our knowledge, this is the first systematic study of IL effects on cellulase substrate binding.
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Affiliation(s)
- Ronny Wahlström
- VTT - Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT, Espoo, Uusimaa, Finland.
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20
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Zhang M, Wang B, Xu B. Measurements of single molecular affinity interactions between carbohydrate-binding modules and crystalline cellulose fibrils. Phys Chem Chem Phys 2013; 15:6508-15. [PMID: 23532050 DOI: 10.1039/c3cp51072g] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Combining atomic force microscopy (AFM) recognition imaging and single molecule dynamic force spectroscopy (SMDFS), we studied the single molecule affinity interactions between the carbohydrate-binding module (CBM) and plant cell wall cellulose using the CBM3a (from Clostridium thermocellum) and CBM2a (from Cellvibrio japonicus) functionalized AFM tips. The binding efficiencies of the CBMs to the cellulose were determined by the binding areas on the crystalline cellulose fibrils surface using the recognition imaging. Several dynamic and kinetic parameters, such as the reconstructed free energy change, energy barrier and bond lifetime constant, were also obtained based on the measured single molecule unbinding forces, which are used to illuminate the affinity of the CBMs binding to the natural and single cellulose surface from a totally different aspect. It was found that CBM3a has a little higher binding efficiency and affinity than CBM2a to both natural and extracted cellulose surfaces and both the CBMs have higher affinities to the natural cell wall cellulose compared to the extracted single cellulose. The in-depth understanding of the binding mechanisms of the CBM-cellulose interactions of this study may pave the way for more efficient plant cell wall degradation and eventually facilitate biofuel production.
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Affiliation(s)
- Mengmeng Zhang
- Single Molecule Study Laboratory, College of Engineering and Nanoscale Science and Engineering Center, University of Georgia, Athens, GA 30602, USA
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21
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Molecular dynamics study of carbohydrate binding module mutants of fungal cellobiohydrolases. Carbohydr Res 2013; 374:96-102. [DOI: 10.1016/j.carres.2013.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 03/31/2013] [Accepted: 04/03/2013] [Indexed: 11/19/2022]
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22
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Guo J, Catchmark JM. Binding Specificity and Thermodynamics of Cellulose-Binding Modules from Trichoderma reesei Cel7A and Cel6A. Biomacromolecules 2013; 14:1268-77. [DOI: 10.1021/bm300810t] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Jing Guo
- Intercollege
Graduate Degree Program in Plant Biology, §Department of Agricultural and Biological
Engineering, ‡Center for NanoCellulosics, The Pennsylvania State University, University Park, Pennsylvania 16802,
United States
| | - Jeffrey M. Catchmark
- Intercollege
Graduate Degree Program in Plant Biology, §Department of Agricultural and Biological
Engineering, ‡Center for NanoCellulosics, The Pennsylvania State University, University Park, Pennsylvania 16802,
United States
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23
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Wu I, Arnold FH. Engineered thermostable fungal Cel6A and Cel7A cellobiohydrolases hydrolyze cellulose efficiently at elevated temperatures. Biotechnol Bioeng 2013; 110:1874-83. [PMID: 23404363 DOI: 10.1002/bit.24864] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Revised: 01/21/2013] [Accepted: 01/28/2013] [Indexed: 11/05/2022]
Abstract
Thermostability is an important feature in industrial enzymes: it increases biocatalyst lifetime and enables reactions at higher temperatures, where faster rates and other advantages ultimately reduce the cost of biocatalysis. Here we report the thermostabilization of a chimeric fungal family 6 cellobiohydrolase (HJPlus) by directed evolution using random mutagenesis and recombination of beneficial mutations. Thermostable variant 3C6P has a half-life of 280 min at 75°C and a T(50) of 80.1°C, a ~15°C increase over the thermostable Cel6A from Humicola insolens (HiCel6A) and a ~20°C increase over that from Hypocrea jecorina (HjCel6A). Most of the mutations also stabilize the less-stable HjCel6A, the wild-type Cel6A closest in sequence to 3C6P. During a 60-h Avicel hydrolysis, 3C6P released 2.4 times more cellobiose equivalents at its optimum temperature (T(opt)) of 75°C than HiCel6A at its T(opt) of 60°C. The total cellobiose equivalents released by HiCel6A at 60°C after 60 h is equivalent to the total released by 3C6P at 75°C after ~6 h, a 10-fold reduction in hydrolysis time. A binary mixture of thermostable Cel6A and Cel7A hydrolyzes Avicel synergistically and released 1.8 times more cellobiose equivalents than the wild-type mixture, both mixtures assessed at their respective T(opt). Crystal structures of HJPlus and 3C6P, determined at 1.5 and 1.2 Å resolution, indicate that the stabilization comes from improved hydrophobic interactions and restricted loop conformations by introduced proline residues.
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Affiliation(s)
- Indira Wu
- Division of Chemistry and Chemical Engineering, California Institute of Technology 210-41, Pasadena, CA 91125, USA
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24
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Larroque M, Barriot R, Bottin A, Barre A, Rougé P, Dumas B, Gaulin E. The unique architecture and function of cellulose-interacting proteins in oomycetes revealed by genomic and structural analyses. BMC Genomics 2012; 13:605. [PMID: 23140525 PMCID: PMC3532174 DOI: 10.1186/1471-2164-13-605] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 10/25/2012] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Oomycetes are fungal-like microorganisms evolutionary distinct from true fungi, belonging to the Stramenopile lineage and comprising major plant pathogens. Both oomycetes and fungi express proteins able to interact with cellulose, a major component of plant and oomycete cell walls, through the presence of carbohydrate-binding module belonging to the family 1 (CBM1). Fungal CBM1-containing proteins were implicated in cellulose degradation whereas in oomycetes, the Cellulose Binding Elicitor Lectin (CBEL), a well-characterized CBM1-protein from Phytophthora parasitica, was implicated in cell wall integrity, adhesion to cellulosic substrates and induction of plant immunity. RESULTS To extend our knowledge on CBM1-containing proteins in oomycetes, we have conducted a comprehensive analysis on 60 fungi and 7 oomycetes genomes leading to the identification of 518 CBM1-containing proteins. In plant-interacting microorganisms, the larger number of CBM1-protein coding genes is expressed by necrotroph and hemibiotrophic pathogens, whereas a strong reduction of these genes is observed in symbionts and biotrophs. In fungi, more than 70% of CBM1-containing proteins correspond to enzymatic proteins in which CBM1 is associated with a catalytic unit involved in cellulose degradation. In oomycetes more than 90% of proteins are similar to CBEL in which CBM1 is associated with a non-catalytic PAN/Apple domain, known to interact with specific carbohydrates or proteins. Distinct Stramenopile genomes like diatoms and brown algae are devoid of CBM1 coding genes. A CBM1-PAN/Apple association 3D structural modeling was built allowing the identification of amino acid residues interacting with cellulose and suggesting the putative interaction of the PAN/Apple domain with another type of glucan. By Surface Plasmon Resonance experiments, we showed that CBEL binds to glycoproteins through galactose or N-acetyl-galactosamine motifs. CONCLUSIONS This study provides insight into the evolution and biological roles of CBM1-containing proteins from oomycetes. We show that while CBM1s from fungi and oomycetes are similar, they team up with different protein domains, either in proteins implicated in the degradation of plant cell wall components in the case of fungi or in proteins involved in adhesion to polysaccharidic substrates in the case of oomycetes. This work highlighted the unique role and evolution of CBM1 proteins in oomycete among the Stramenopile lineage.
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Affiliation(s)
- Mathieu Larroque
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
| | - Roland Barriot
- Université de Toulouse, UPS, Laboratoire de Microbiologie et Génétique Moléculaire, Toulouse F-31000, France
- Centre National de la Recherche Scientifique; LMGM, Toulouse F-31000, France
| | - Arnaud Bottin
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
| | - Annick Barre
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
- Present address: Université de Toulouse, UPS, Laboratoire PHARMA-DEV IRD UMR 152, 35 Chemin des Maraîchers, Toulouse 31400, France
| | - Pierre Rougé
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
- Present address: Université de Toulouse, UPS, Laboratoire PHARMA-DEV IRD UMR 152, 35 Chemin des Maraîchers, Toulouse 31400, France
| | - Bernard Dumas
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
| | - Elodie Gaulin
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
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25
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Sugimoto N, Igarashi K, Samejima M. Cellulose affinity purification of fusion proteins tagged with fungal family 1 cellulose-binding domain. Protein Expr Purif 2012; 82:290-6. [PMID: 22305911 DOI: 10.1016/j.pep.2012.01.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 01/11/2012] [Accepted: 01/13/2012] [Indexed: 11/23/2022]
Abstract
N- or C-terminal fusions of red-fluorescent protein (RFP) with various fungal cellulose-binding domains (CBDs) belonging to carbohydrate binding module (CBM) family 1 were expressed in a Pichia pastoris expression system, and the resulting fusion proteins were used to examine the feasibility of large-scale affinity purification of CBD-tagged proteins on cellulose columns. We found that RFP fused with CBD from Trichoderma reesei CBHI (CBD(Tr)(CBHI)) was expressed at up to 1.2g/l in the culture filtrate, which could be directly injected into the cellulose column. The fusion protein was tightly adsorbed on the cellulose column in the presence of a sufficient amount of ammonium sulfate and was efficiently eluted with pure water. Bovine serum albumin (BSA) was not captured under these conditions, whereas both BSA and the fusion protein were adsorbed on a phenyl column, indicating that the cellulose column can be used for the purification of not only hydrophilic proteins but also for hydrophobic proteins. Recovery of various fusion proteins exceeded 80%. Our results indicate that protein purification by expression of a target protein as a fusion with a fungal family 1 CBD tag in a yeast expression system, followed by affinity purification on a cellulose column, is simple, effective and easily scalable.
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Affiliation(s)
- Naohisa Sugimoto
- Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Caparrós C, Lant N, Smets J, Cavaco-Paulo A. Effects of adsorption properties and mechanical agitation of two detergent cellulases towards cotton cellulose. BIOCATAL BIOTRANSFOR 2012. [DOI: 10.3109/10242422.2012.666840] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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27
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Cellulolytic Enzyme Production and Enzymatic Hydrolysis for Second-Generation Bioethanol Production. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2012; 128:1-24. [DOI: 10.1007/10_2011_131] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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28
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Abstract
Natural cellulolytic enzyme systems as well as leading commercial cellulase cocktails are dominated by enzymes that degrade cellulose chains in a processive manner. Despite the abundance of processivity among natural cellulases, the molecular basis as well as the biotechnological implications of this mechanism are only partly understood. One of the major limitations lies in the fact that it is not straightforward to measure and quantify processivity in what essentially are biphasic experimental systems. Here, we describe and discuss both well-established methods and newer methods for measuring cellulase processivity. In addition, we discuss recent insights from studies on chitinases that may help direct further studies on processivity in cellulases.
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Affiliation(s)
- Svein J Horn
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway
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29
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Novel family of carbohydrate-binding modules revealed by the genome sequence of Spirochaeta thermophila DSM 6192. Appl Environ Microbiol 2011; 77:5483-9. [PMID: 21685171 DOI: 10.1128/aem.00523-11] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Spirochaeta thermophila is a thermophilic, free-living, and cellulolytic anaerobe. The genome sequence data for this organism have revealed a high density of genes encoding enzymes from more than 30 glycoside hydrolase (GH) families and a noncellulosomal enzyme system for (hemi)cellulose degradation. Functional screening of a fosmid library whose inserts were mapped on the S. thermophila genome sequence allowed the functional annotation of numerous GH open reading frames (ORFs). Seven different GH ORFs from the S. thermophila DSM 6192 genome, all putative β-glycanase ORFs according to sequence similarity analysis, contained a highly conserved novel GH-associated module of unknown function at their C terminus. Four of these GH enzymes were experimentally verified as xylanase, β-glucanase, β-glucanase/carboxymethylcellulase (CMCase), and CMCase. Binding experiments performed with the recombinantly expressed and purified GH-associated module showed that it represents a new carbohydrate-binding module (CBM) that binds to microcrystalline cellulose and is highly specific for this substrate. In the course of this work, the new CBM type was only detected in Spirochaeta, but recently we found sequences with detectable similarity to the module in the draft genomes of Cytophaga fermentans and Mahella australiensis, both of which are phylogenetically very distant from S. thermophila and noncellulolytic, yet inhabit similar environments. This suggests a possibly broad distribution of the module in nature.
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30
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Jäger G, Wu Z, Garschhammer K, Engel P, Klement T, Rinaldi R, Spiess AC, Büchs J. Practical screening of purified cellobiohydrolases and endoglucanases with α-cellulose and specification of hydrodynamics. BIOTECHNOLOGY FOR BIOFUELS 2010; 3:18. [PMID: 20718965 PMCID: PMC2936879 DOI: 10.1186/1754-6834-3-18] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Accepted: 08/18/2010] [Indexed: 05/08/2023]
Abstract
BACKGROUND It is important to generate biofuels and society must be weaned from its dependency on fossil fuels. In order to produce biofuels, lignocellulose is pretreated and the resulting cellulose is hydrolyzed by cellulases such as cellobiohydrolases (CBH) and endoglucanases (EG). Until now, the biofuel industry has usually applied impractical celluloses to screen for cellulases capable of degrading naturally occurring, insoluble cellulose. This study investigates how these cellulases adsorb and hydrolyze insoluble α-cellulose - considered to be a more practical substrate which mimics the alkaline-pretreated biomass used in biorefineries. Moreover, this study investigates how hydrodynamics affects cellulase adsorption and activity onto α-cellulose. RESULTS First, the cellulases CBH I, CBH II, EG I and EG II were purified from Trichoderma reesei and CBH I and EG I were utilized in order to study and model the adsorption isotherms (Langmuir) and kinetics (pseudo-first-order). Second, the adsorption kinetics and cellulase activities were studied under different hydrodynamic conditions, including liquid mixing and particle suspension. Third, in order to compare α-cellulose with three typically used celluloses, the exact cellulase activities towards all four substrates were measured.It was found that, using α-cellulose, the adsorption models fitted to the experimental data and yielded parameters comparable to those for filter paper. Moreover, it was determined that higher shaking frequencies clearly improved the adsorption of cellulases onto α-cellulose and thus bolstered their activity. Complete suspension of α-cellulose particles was the optimal operating condition in order to ensure efficient cellulase adsorption and activity. Finally, all four purified cellulases displayed comparable activities only on insoluble α-cellulose. CONCLUSIONS α-Cellulose is an excellent substrate to screen for CBHs and EGs. This current investigation shows in detail, for the first time, the adsorption of purified cellulases onto α-cellulose, the effect of hydrodynamics on cellulase adsorption and the correlation between the adsorption and the activity of cellulases at different hydrodynamic conditions. Complete suspension of the substrate has to be ensured in order to optimize the cellulase attack. In the future, screenings should be conducted with α-cellulose so that proper cellulases are selected to best hydrolyze the real alkaline-pretreated biomass used in biorefineries.
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Affiliation(s)
- Gernot Jäger
- AVT-Aachener Verfahrenstechnik, Biochemical Engineering, RWTH Aachen University, Worringerweg 1, D-52074 Aachen, Germany
| | - Zhuojun Wu
- AVT-Aachener Verfahrenstechnik, Biochemical Engineering, RWTH Aachen University, Worringerweg 1, D-52074 Aachen, Germany
| | - Kerstin Garschhammer
- AVT-Aachener Verfahrenstechnik, Biochemical Engineering, RWTH Aachen University, Worringerweg 1, D-52074 Aachen, Germany
| | - Philip Engel
- AVT-Aachener Verfahrenstechnik, Biochemical Engineering, RWTH Aachen University, Worringerweg 1, D-52074 Aachen, Germany
| | - Tobias Klement
- AVT-Aachener Verfahrenstechnik, Biochemical Engineering, RWTH Aachen University, Worringerweg 1, D-52074 Aachen, Germany
| | - Roberto Rinaldi
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Antje C Spiess
- AVT-Aachener Verfahrenstechnik, Biochemical Engineering, RWTH Aachen University, Worringerweg 1, D-52074 Aachen, Germany
| | - Jochen Büchs
- AVT-Aachener Verfahrenstechnik, Biochemical Engineering, RWTH Aachen University, Worringerweg 1, D-52074 Aachen, Germany
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31
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Engineering of Clostridium phytofermentans Endoglucanase Cel5A for improved thermostability. Appl Environ Microbiol 2010; 76:4914-7. [PMID: 20511418 DOI: 10.1128/aem.00958-10] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A family 5 glycoside hydrolase from Clostridium phytofermentans was cloned and engineered through a cellulase cell surface display system in Escherichia coli. The presence of cell surface anchoring, a cellulose binding module, or a His tag greatly influenced the activities of wild-type and mutant enzymes on soluble and solid cellulosic substrates, suggesting the high complexity of cellulase engineering. The best mutant had 92%, 36%, and 46% longer half-lives at 60 degrees C on carboxymethyl cellulose, regenerated amorphous cellulose, and Avicel, respectively.
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32
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Ciolacu D, Kovac J, Kokol V. The effect of the cellulose-binding domain from Clostridium cellulovorans on the supramolecular structure of cellulose fibers. Carbohydr Res 2010; 345:621-30. [DOI: 10.1016/j.carres.2009.12.023] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Revised: 12/14/2009] [Accepted: 12/22/2009] [Indexed: 12/01/2022]
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33
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Liu Y, Yoshida M, Kurakata Y, Miyazaki T, Igarashi K, Samejima M, Fukuda K, Nishikawa A, Tonozuka T. Crystal structure of a glycoside hydrolase family 6 enzyme, CcCel6C, a cellulase constitutively produced by Coprinopsis cinerea. FEBS J 2010; 277:1532-42. [DOI: 10.1111/j.1742-4658.2010.07582.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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34
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Tu M, Zhang X, Paice M, MacFarlane P, Saddler JN. The potential of enzyme recycling during the hydrolysis of a mixed softwood feedstock. BIORESOURCE TECHNOLOGY 2009; 100:6407-6415. [PMID: 19632826 DOI: 10.1016/j.biortech.2009.06.108] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2008] [Revised: 03/19/2009] [Accepted: 06/27/2009] [Indexed: 05/28/2023]
Abstract
Despite recent improvement in cellulase enzymes properties, the high cost associated with the hydrolysis step remains a major impediment to the commercialization of full-scale lignocellulose-to-ethanol bioconversion process. As part of a research effort to develop a commercial process for bioconversion of softwood residues, we have examined the potential for recycling enzymes during the hydrolysis of mixed softwood substrate pretreated by organosolv process. We have used response surface methodology to determine the optimal temperature, pH, ionic strength, and surfactant (Tween 80) concentration for maximizing the recovery of bound protein and enzyme activity from the residual substrates after hydrolysis. Data analysis showed that the temperature, pH and surfactant concentration were the major factors governing enzyme desorption from residual substrate. The optimized conditions were temperature 44.4 degrees C, pH 5.3 and 0.5% Tween 80. The optimal conditions significantly increased the hydrolysis yield by 25% after three rounds of hydrolysis. This bound enzyme desorption combining with free enzyme re-adsorption is a potential method to recover cellulase enzymes and reduce the cost of enzymatic hydrolysis.
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Affiliation(s)
- Maobing Tu
- School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL 36849-5418, USA.
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35
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Kumar R, Wyman CE. Cellulase adsorption and relationship to features of corn stover solids produced by leading pretreatments. Biotechnol Bioeng 2009; 103:252-67. [PMID: 19195015 DOI: 10.1002/bit.22258] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Although essential to enzymatic hydrolysis of cellulosic biomass to sugars for fermentation to ethanol or other products, enzyme adsorption and its relationship to substrate features has received limited attention, and little data and insight have been developed on cellulase adsorption for promising pretreatment options, with almost no data available to facilitate comparisons. Therefore, adsorption of cellulase on Avicel, and of cellulase and xylanase on corn stover solids resulting from ammonia fiber expansion (AFEX), ammonia recycled percolation (ARP), controlled pH, dilute acid, lime, and sulfur dioxide (SO(2)) pretreatments were measured at 4 degrees C. Langmuir adsorption parameters were then estimated by non-linear regression using Polymath software, and cellulase accessibility to cellulose was estimated based on adsorption data for pretreated solids and lignin left after carbohydrate digestion. To determine the impact of delignification and deacetylation on cellulose accessibility, purified CBHI (Cel7A) adsorption at 4 degrees C and hydrolysis with whole cellulase were followed for untreated (UT) corn stover. In all cases, cellulase attained equilibrium in less than 2 h, and upon dilution, solids pretreated by controlled pH technology showed the greatest desorption followed by solids from dilute acid and SO(2) pretreatments. Surprisingly, the lowest desorption was measured for Avicel glucan followed by solids from AFEX pretreatment. The higher cellulose accessibility for AFEX and lime pretreated solids could account for the good digestion reported in the literature for these approaches. Lime pretreated solids had the greatest xylanase capacity and AFEX solids the least, showing pretreatment pH did not seem to be controlling. The 24 h glucan hydrolysis rate data had a strong relationship to cellulase adsorption capacities, while 24 h xylan hydrolysis rate data showed no relationship to xylanase adsorption capacities. Furthermore, delignification greatly enhanced enzyme effectiveness but had a limited effect on cellulose accessibility. And because delignification enhanced release of xylose more than glucose, it appears that lignin did not directly control cellulose accessibility but restricted xylan accessibility which in turn controlled access to cellulose. Reducing the acetyl content in corn stover solids significantly improved both cellulose accessibility and enzyme effectiveness.
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Affiliation(s)
- Rajeev Kumar
- Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire, USA
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36
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Xu F, Ding H, Osborn D, Tejirian A, Brown K, Albano W, Sheehy N, Langston J. Partition of enzymes between the solvent and insoluble substrate during the hydrolysis of lignocellulose by cellulases. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.molcatb.2007.10.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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37
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Josefsson P, Henriksson G, Wågberg L. The Physical Action of Cellulases Revealed by a Quartz Crystal Microbalance Study Using Ultrathin Cellulose Films and Pure Cellulases. Biomacromolecules 2007; 9:249-54. [PMID: 18163575 DOI: 10.1021/bm700980b] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Peter Josefsson
- Royal Institute of Technology, Fibre and Polymer Technology, Teknikringen 56, 100 44 Stockholm, Sweden
| | - Gunnar Henriksson
- Royal Institute of Technology, Fibre and Polymer Technology, Teknikringen 56, 100 44 Stockholm, Sweden
| | - Lars Wågberg
- Royal Institute of Technology, Fibre and Polymer Technology, Teknikringen 56, 100 44 Stockholm, Sweden
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38
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Filonova L, Kallas AM, Greffe L, Johansson G, Teeri TT, Daniel G. Analysis of the Surfaces of Wood Tissues and Pulp Fibers Using Carbohydrate-Binding Modules Specific for Crystalline Cellulose and Mannan. Biomacromolecules 2006; 8:91-7. [PMID: 17206793 DOI: 10.1021/bm060632z] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Carbohydrate binding modules (CBMs) are noncatalytic substrate binding domains of many enzymes involved in carbohydrate metabolism. Here we used fluorescent labeled recombinant CBMs specific for crystalline cellulose (CBM1(HjCel7A)) and mannans (CBM27(TmMan5) and CBM35(CjMan5C)) to analyze the complex surfaces of wood tissues and pulp fibers. The crystalline cellulose CBM1(HjCel7A) was found as a reliable marker of both bacterially produced and plant G-layer cellulose, and labeling of spruce pulp fibers with CBM1(HjCel7A) revealed a signal that increased with degree of fiber damage. The mannan-specific CBM27(TmMan5) and CBM35(CjMan5C) CBMs were found to be more specific reagents than a monoclonal antibody specific for (1-->4)-beta-mannan/galacto-(1-->4)-beta-mannan for mapping carbohydrates on native substrates. We have developed a quantitative fluorometric method for analysis of crystalline cellulose accumulation on fiber surfaces and shown a quantitative difference in crystalline cellulose binding sites in differently processed pulp fibers. Our results indicated that CBMs provide useful, novel tools for monitoring changes in carbohydrate content of nonuniform substrate surfaces, for example, during wood or pulping processes and possibly fiber biosynthesis.
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Affiliation(s)
- Lada Filonova
- Department of Wood Science, Swedish University of Agricultural Sciences, Uppsala, Sweden.
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39
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Shoseyov O, Shani Z, Levy I. Carbohydrate binding modules: biochemical properties and novel applications. Microbiol Mol Biol Rev 2006; 70:283-95. [PMID: 16760304 PMCID: PMC1489539 DOI: 10.1128/mmbr.00028-05] [Citation(s) in RCA: 351] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Polysaccharide-degrading microorganisms express a repertoire of hydrolytic enzymes that act in synergy on plant cell wall and other natural polysaccharides to elicit the degradation of often-recalcitrant substrates. These enzymes, particularly those that hydrolyze cellulose and hemicellulose, have a complex molecular architecture comprising discrete modules which are normally joined by relatively unstructured linker sequences. This structure is typically comprised of a catalytic module and one or more carbohydrate binding modules (CBMs) that bind to the polysaccharide. CBMs, by bringing the biocatalyst into intimate and prolonged association with its substrate, allow and promote catalysis. Based on their properties, CBMs are grouped into 43 families that display substantial variation in substrate specificity, along with other properties that make them a gold mine for biotechnologists who seek natural molecular "Velcro" for diverse and unusual applications. In this article, we review recent progress in the field of CBMs and provide an up-to-date summary of the latest developments in CBM applications.
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Affiliation(s)
- Oded Shoseyov
- The Institute of Plant Science and Genetics in Agriculture, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel.
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40
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Ximenes EA, Chen H, Kataeva IA, Cotta MA, Felix CR, Ljungdahl LG, Li XL. A mannanase, ManA, of the polycentric anaerobic fungus Orpinomyces sp. strain PC-2 has carbohydrate binding and docking modules. Can J Microbiol 2006; 51:559-68. [PMID: 16175204 PMCID: PMC6448567 DOI: 10.1139/w05-033] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The anaerobic fungus Orpinomyces sp. strain PC-2 produces a broad spectrum of glycoside hydrolases, most of which are components of a high molecular mass cellulosomal complex. Here we report about a cDNA (manA) having 1924 bp isolated from the fungus and found to encode a polypeptide of 579 amino acid residues. Analysis of the deduced sequence revealed that it had a mannanase catalytic module, a family 1 carbohydrate-binding module, and a noncatalytic docking module. The catalytic module was homologous to aerobic fungal mannanases belonging to family 5 glycoside hydrolases, but unrelated to the previously isolated mannanases (family 26) of the anaerobic fungus Piromyces. No mannanase activity could be detected in Escherichia coli harboring a manA-containing plasmid. The manA was expressed in Saccharomyces cerevisiae and ManA was secreted into the culture medium in multiple forms. The purified extracellular heterologous mannanase hydrolyzed several types of mannan but lacked activity against cellulose, chitin, or beta-glucan. The enzyme had high specific activity toward locust bean mannan and an extremely broad pH profile. It was stable for several hours at 50 degrees C, but was rapidly inactivated at 60 degrees C. The carbohydrate-binding module of the Man A produced separately in E. coli bound preferably to insoluble lignocellulosic substrates, suggesting that it might play an important role in the complex enzyme system of the fungus for lignocellulose degradation.
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Affiliation(s)
- Eduardo A. Ximenes
- Laboratorio De Enzimologia, Departmento De Biologia Celular, Universidade De Brasilia, Asa Norte, Brasilia-DF-Brazil 70910-900, Brazil
| | - Huizhong Chen
- Division of Microbiology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079-9502, USA
| | - Irina A. Kataeva
- Department of Biochemistry and Molecular Biology and Center for Biological Resource Recovery, The University of Georgia, Athens, GA 30602-7229, USA
| | - Michael A. Cotta
- Fermentation Biotechnology Research Unit, National Center for Agricultural Utilization Research, USDA/ARS, 1815 N. University Street, Peoria, IL 61604, USA
| | - Carlos R. Felix
- Laboratorio De Enzimologia, Departmento De Biologia Celular, Universidade De Brasilia, Asa Norte, Brasilia-DF-Brazil 70910-900, Brazil
| | - Lars G. Ljungdahl
- Department of Biochemistry and Molecular Biology and Center for Biological Resource Recovery, The University of Georgia, Athens, GA 30602-7229, USA
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41
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Li YH, Ding M, Wang J, Xu GJ, Zhao F. A novel thermoacidophilic endoglucanase, Ba-EGA, from a new cellulose-degrading bacterium, Bacillus sp.AC-1. Appl Microbiol Biotechnol 2005; 70:430-6. [PMID: 16142468 DOI: 10.1007/s00253-005-0075-x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2005] [Revised: 06/20/2005] [Accepted: 06/22/2005] [Indexed: 11/24/2022]
Abstract
A newly discovered bacterium, strain AC1, containing cellulase was isolated from the gastric juice of the mollusca, Ampullaria crosseans. Analysis of the 16S rDNA sequence and carbon sources revealed that the bacterium belonged to the genus Bacillus. A novel endoglucanase (Ba-EGA) was purified from culture supernatants of the bacterium growing in CMC-Na (low viscosity) induction medium. The cellulase was purified about 150-fold by ammonium sulfate fractionation, ion exchange, hydrophobic, and gel filtration chromatography, with a specific activity of 35.0 IU/mg. The molecular mass of the enzyme was 67 kDa. N-terminal amino acid sequencing revealed a sequence of SDYNYVEVLQKSILF, which had high homology with endoglucanases from the Bacillus and Clostridium species. The maximal activity of the enzyme with the substrate of CM-cellulose is at pH 4.5-6.5 and 70 degrees C, respectively. The studies on pH and temperature stability showed that the Ba-EGA is stable enough between pH 7.5 and 10.5 at 30 degrees C for 2 h, and more than 80% of the activity still remains when incubation was prolonged to 1 h at 50 degrees C. The activity of the enzyme was significantly inhibited by Fe(2+), Cu(2+) (5.0 mM of each), and sodium dodecyl sulfate (SDS) (0.5%) and obviously activated by Tween 20 and Triton X-100 (0.25% each). Binding studies revealed that the Ba-EGA had cellulose-binding domain.
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Affiliation(s)
- Yan-Hong Li
- Key Laboratory of Proteomics, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, China
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42
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Yoshida M, Igarashi K, Wada M, Kaneko S, Suzuki N, Matsumura H, Nakamura N, Ohno H, Samejima M. Characterization of carbohydrate-binding cytochrome b562 from the white-rot fungus Phanerochaete chrysosporium. Appl Environ Microbiol 2005; 71:4548-55. [PMID: 16085848 PMCID: PMC1183321 DOI: 10.1128/aem.71.8.4548-4555.2005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2004] [Accepted: 02/18/2005] [Indexed: 11/20/2022] Open
Abstract
cDNA encoding a hemoprotein similar to the cytochrome domain of extracellular flavocytochrome cellobiose dehydrogenase (CDH) was cloned from the white-rot fungus Phanerochaete chrysosporium. The deduced amino acid sequence implies that there is a two-domain structure consisting of an N-terminal cytochrome domain and a C-terminal family 1 carbohydrate-binding module (CBM1) but that the flavin-containing domain of CDH is not present. The gene transcripts were observed in cultures in cellulose medium but not in cultures in glucose medium, suggesting that there is regulation by carbon catabolite repression. The gene was successfully overexpressed in Pichia pastoris, and the recombinant protein was designated carbohydrate-binding cytochrome b562 (CBCyt. b562). The resonance Raman spectrum suggested that the heme of CBCyt. b562 is 6-coordinated in both the ferric and ferrous states. Moreover, the redox potential measured by cyclic voltammetry was similar to that of the cytochrome domain of CDH. These results suggest that the redox characteristics may be similar to those of the cytochrome domain of CDH, and so CBCyt. b562 may have an electron transfer function. In a binding study with various carbohydrates, CBCyt. b562 was adsorbed with high affinity on both cellulose and chitin. As far as we know, this is the first example of a CBM1 connected to a domain without apparent catalytic activity for carbohydrate; this CBM1 may play a role in localization of the redox protein on the surface of cellulose or on the fungal sheath in vivo.
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Affiliation(s)
- Makoto Yoshida
- Department of Biomaterials Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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43
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Mulakala C, Reilly PJ. Hypocrea jecorina (Trichoderma reesei) Cel7A as a molecular machine: A docking study. Proteins 2005; 60:598-605. [PMID: 16001418 DOI: 10.1002/prot.20547] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Hypocrea jecorina (formerly Trichoderma reesei) Cel7A has a catalytic domain (CD) and a cellulose-binding domain (CBD) separated by a highly glycosylated linker. Very little is known of how the 2 domains interact to degrade crystalline cellulose. Based on the interaction energies and forces on cello-oligosaccharides computationally docked to the CD and CBD, we propose a molecular machine model, where the CBD wedges itself under a free chain end on the crystalline cellulose surface and feeds it to the CD active site tunnel. Enzyme-substrate interactions produce the forces required to pull cellulose chains from the surface and also to help the enzyme move on the cellulose chain for processive hydrolysis. The energy to generate these forces is ultimately derived from the chemical energy of glycosidic bond breakage.
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Affiliation(s)
- Chandrika Mulakala
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011-2230, USA
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44
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Hildén L, Johansson G. Recent developments on cellulases and carbohydrate-binding modules with cellulose affinity. Biotechnol Lett 2005; 26:1683-93. [PMID: 15604820 DOI: 10.1007/s10529-004-4579-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
This review concerns basic research on cellulases and cellulose-specific carbohydrate-binding modules (CBMs). As a background, glycosyl hydrolases are also briefly reviewed. The nomenclature of cellulases and CBMs is discussed. The main cellulase-producing organisms and their cellulases are described. Synergy, enantioseparation, cellulases in plants, cellulosomes, cellulases and CBMs as analytical tools and cellulase-like enzymes are also briefly reviewed.
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Affiliation(s)
- Lars Hildén
- WURC, Department of Wood Science, Swedish University of Agricultural Sciences, Box 7008, Uppsala, 750 07, Sweden.
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45
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Zhang YHP, Lynd LR. Toward an aggregated understanding of enzymatic hydrolysis of cellulose: noncomplexed cellulase systems. Biotechnol Bioeng 2005; 88:797-824. [PMID: 15538721 DOI: 10.1002/bit.20282] [Citation(s) in RCA: 883] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Information pertaining to enzymatic hydrolysis of cellulose by noncomplexed cellulase enzyme systems is reviewed with a particular emphasis on development of aggregated understanding incorporating substrate features in addition to concentration and multiple cellulase components. Topics considered include properties of cellulose, adsorption, cellulose hydrolysis, and quantitative models. A classification scheme is proposed for quantitative models for enzymatic hydrolysis of cellulose based on the number of solubilizing activities and substrate state variables included. We suggest that it is timely to revisit and reinvigorate functional modeling of cellulose hydrolysis, and that this would be highly beneficial if not necessary in order to bring to bear the large volume of information available on cellulase components on the primary applications that motivate interest in the subject.
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Acosta-Rodríguez I, Piñón-Escobedo C, Zavala-Páramo MG, López-Romero E, Cano-Camacho H. Degradation of cellulose by the bean-pathogenic fungus Colletotrichum lindemuthianum. Production of extracellular cellulolytic enzymes by cellulose induction. Antonie van Leeuwenhoek 2005; 87:301-10. [PMID: 15928983 DOI: 10.1007/s10482-004-6422-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2004] [Accepted: 11/18/2004] [Indexed: 11/26/2022]
Abstract
Colletotrichum lindemuthianum was able to grow and produce extracellular cellulolytic activity in a defined medium containing cellulose as the main carbon substrate. As measured either by the hydrolysis of 4-methylumbelliferyl-beta-D -cellotrioside or the release of glucose from carboxymethylcellulose, activity reached a peak after 13 days of incubation and then declined whereas growth markedly increased afterwards. Detection of glucose in carboxymethylcellulose hydrolysates suggested the concerted operation of endo-1,4-beta-glucanase, cellobiohydrolase (exo-1,4-beta-glucanase) and beta-glucosidase activities. The highest levels of cellulolytic activity were obtained in media supplemented with cellulose and glutamate. Other carbon and nitrogen sources markedly influenced growth and enzyme production. Oligonucleotides homologous to specific regions of the cellobiohydrolase-encoding cbhII gene from Trichoderma reesei were used to isolate a C. lindemuthianum cbhII-DNA fragment whose sequence revealed homologies of 98% and 92% with the nucleotide and the deduced amino acid sequences of the corresponding cbhII-DNA of T. reesei, respectively. RT-PCR and Southern blot analyses of total RNA samples obtained from cellulose-grown but not from glucose-grown mycelium revealed the expression of the corresponding cbhII transcript. The cbhII-cDNA fragment was cloned and sequenced.
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Affiliation(s)
- Ismael Acosta-Rodríguez
- Facultad de Ciencias Químicas, Universidad Autónoma de San Luis Potosí, San Luis Potosí, S.L.P.78320, México
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Eklund M, Sandström K, Teeri TT, Nygren PA. Site-specific and reversible anchoring of active proteins onto cellulose using a cellulosome-like complex. J Biotechnol 2004; 109:277-86. [PMID: 15066765 DOI: 10.1016/j.jbiotec.2004.01.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2003] [Revised: 12/22/2003] [Accepted: 01/16/2004] [Indexed: 10/26/2022]
Abstract
Protein engineering strategies facilitating controlled and spontaneous assembly of macromolecular complexes are of great interest for the design of artificial multi-enzyme systems of pre-defined composition. Here we have combined affinity proteins from different sources to achieve specific and reversible anchoring of affinity domain-tagged reporter proteins to a cellulose-anchored fusion protein. The design principle mimics the architecture of macromolecular cellulosome complexes produced by some cellulolytic microbes. A fusion protein between a cellulose-binding module (CBM1Cel6A) of the Trichoderma reesei cellobiohydrolase Cel6A and a five-domain staphylococcal protein A (SPA) was constructed to serve as platform for docking of easily detectable reporter proteins onto cellulose surfaces. In turn, the reporter proteins were produced as fusions to two copies of a SPA-binding affinity protein (an affibody denoted Z(SPA-1)), selected from a phage display library constructed by combinatorial protein engineering. In a series of experiments, involving repeated washing and low pH elution, affinity-tagged Enhanced Green Fluorescent Protein (EGFP) and Fusarium solani pisi lipase cutinase reporter proteins were both found to be specifically directed from solution to the same region of a cellulose filter paper where SPA-CBM1Cel6A fusion protein had been previously applied. This showed that the SPA-CBM1Cel6A fusion protein had been stably anchored to the cellulose surface without loss of binding capacity and that the interaction between SPA and the Z(SPA-1) affibody domains was selective. The generality of this biospecificity-driven system for assembly applications is discussed.
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Affiliation(s)
- Malin Eklund
- Department of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Center, Roslagstullsbacken 21, SE-106 91 Stockholm, Sweden
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Pinto R, Moreira S, Mota M, Gama M. Studies on the cellulose-binding domains adsorption to cellulose. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:1409-13. [PMID: 15803726 DOI: 10.1021/la035611u] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Cellulose-binding domains (CBD) are modular peptides, present in many glycanases, which anchor these enzymes to the substrate. In this work, the effect of CBD adsorption on the surface properties of a model cellulose, Whatman CF11, was studied. The methods applied include inverse gas chromatography (IGC), ESCA, X-ray diffraction, and scanning electron microscopy (SEM). The CBD partition affinity (0.85 L/g) was calculated from adsorption isotherms. However, true adsorption equilibrium does not exist, since CBDs are apparently irreversibly adsorbed to the fibers. Both IGC and ESCA showed that fibers with adsorbed CBD have a lower acidic character and also a slightly higher affinity toward aliphatic molecules. This may however be a consequence of an increased surface area, a hypothesis that is supported by microscopic observations. The crystallinity index was not affected by CBD treatment.
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Affiliation(s)
- Ricardo Pinto
- Centro de Engenharia Biológica - CEB, Largo do Paço, Universidade do Minho, 4710-057 Braga, Portugal
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Comparison of domains function between cellobiohydrolase I and endoglucanase I from Trichoderma pseudokoningii S-38 by limited proteolysis. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1381-1177(03)00070-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Paldi T, Levy I, Shoseyov O. Glucoamylase starch-binding domain of Aspergillus niger B1: molecular cloning and functional characterization. Biochem J 2003; 372:905-10. [PMID: 12646045 PMCID: PMC1223447 DOI: 10.1042/bj20021527] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2002] [Revised: 03/13/2003] [Accepted: 03/19/2003] [Indexed: 11/17/2022]
Abstract
Carbohydrate-binding modules (CBMs) are protein domains located within a carbohydrate-active enzyme, with a discrete fold that can be separated from the catalytic domain. Starch-binding domains (SBDs) are CBMs that are usually found at the C-terminus in many amylolytic enzymes. The SBD from Aspergillus niger B1 (CMI CC 324262) was cloned and expressed in Escherichia coli as an independent domain and the recombinant protein was purified on starch. The A. niger B1 SBD was found to be similar to SBD from A. kawachii, A. niger var. awamori and A. shirusami (95-96% identity) and was classified as a member of the CBM family 20. Characterization of SBD binding to starch indicated that it is essentially irreversible and that its affinity to cationic or anionic starch, as well as to potato or corn starch, does not differ significantly. These observations indicate that the fundamental binding area on these starches is essentially the same. Natural and chemically modified starches are among the most useful biopolymers employed in the industry. Our study demonstrates that SBD binds effectively to both anionic and cationic starch.
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Affiliation(s)
- Tzur Paldi
- The Institute of Plant Science and Genetics in Agriculture, The Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel
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