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Chaudhari YB, Várnai A, Sørlie M, Horn SJ, Eijsink VGH. Engineering cellulases for conversion of lignocellulosic biomass. Protein Eng Des Sel 2023; 36:gzad002. [PMID: 36892404 PMCID: PMC10394125 DOI: 10.1093/protein/gzad002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 02/13/2023] [Accepted: 02/24/2023] [Indexed: 03/10/2023] Open
Abstract
Lignocellulosic biomass is a renewable source of energy, chemicals and materials. Many applications of this resource require the depolymerization of one or more of its polymeric constituents. Efficient enzymatic depolymerization of cellulose to glucose by cellulases and accessory enzymes such as lytic polysaccharide monooxygenases is a prerequisite for economically viable exploitation of this biomass. Microbes produce a remarkably diverse range of cellulases, which consist of glycoside hydrolase (GH) catalytic domains and, although not in all cases, substrate-binding carbohydrate-binding modules (CBMs). As enzymes are a considerable cost factor, there is great interest in finding or engineering improved and robust cellulases, with higher activity and stability, easy expression, and minimal product inhibition. This review addresses relevant engineering targets for cellulases, discusses a few notable cellulase engineering studies of the past decades and provides an overview of recent work in the field.
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Affiliation(s)
- Yogesh B Chaudhari
- Faculty of Chemistry, Biotechnology, and Food Science, NMBU-Norwegian University of Life Sciences, P.O. Box 5003, 1432 Ås, Norway
| | - Anikó Várnai
- Faculty of Chemistry, Biotechnology, and Food Science, NMBU-Norwegian University of Life Sciences, P.O. Box 5003, 1432 Ås, Norway
| | - Morten Sørlie
- Faculty of Chemistry, Biotechnology, and Food Science, NMBU-Norwegian University of Life Sciences, P.O. Box 5003, 1432 Ås, Norway
| | - Svein J Horn
- Faculty of Chemistry, Biotechnology, and Food Science, NMBU-Norwegian University of Life Sciences, P.O. Box 5003, 1432 Ås, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology, and Food Science, NMBU-Norwegian University of Life Sciences, P.O. Box 5003, 1432 Ås, Norway
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A Combined Study on Optimization, In Silico Modeling, and Genetic Modification of Large Scale Microbial Cellulase Production. Biochem Res Int 2022; 2022:4598937. [PMID: 36589721 PMCID: PMC9797302 DOI: 10.1155/2022/4598937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/28/2022] [Accepted: 11/29/2022] [Indexed: 12/24/2022] Open
Abstract
Cellulase is a biocatalyst that hydrolyzes cellulosic biomass and is considered a major group of industrial enzymes for its applications. Extensive work has been done on microbial cellulase but fungi are considered a novel strain for their maximum cellulase production. Production cost and novel microbial strains are major challenges for its improvement where cheap agro wastes can be essential sources of cellulose as substrates. The researcher searches for more cellulolytic microbes from natural sources but the production level of isolated strains is comparatively low. So genetic modification or mutation can be employed for large-scale cellulase production before optimization. After genetic modification than in silico molecular modeling can be evaluated for substrate molecule's binding affinity. In this review, we focus not only on the conventional methods of cellulase production but also on modern biotechnological approaches applied to cellulase production by a sequential study on common cellulase-producing microbes, modified microbes, culture media, carbon sources, substrate pretreatment process, and the importance of optimum pH and temperature on fermentation. In this review, we also compare different cellulase activity determination methods. As a result, this review provides insights into the interrelationship between the characteristics of optimizing different culture conditions, genetic modification, and in silico enzyme modeling for the production of cellulase enzymes, which may aid in the advancement of large-scale integrated enzyme manufacturing of substrate-specific enzymes.
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Cellulolytic and Xylanolytic Enzymes from Yeasts: Properties and Industrial Applications. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27123783. [PMID: 35744909 PMCID: PMC9229053 DOI: 10.3390/molecules27123783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 06/08/2022] [Accepted: 06/09/2022] [Indexed: 11/17/2022]
Abstract
Lignocellulose, the main component of plant cell walls, comprises polyaromatic lignin and fermentable materials, cellulose and hemicellulose. It is a plentiful and renewable feedstock for chemicals and energy. It can serve as a raw material for the production of various value-added products, including cellulase and xylanase. Cellulase is essentially required in lignocellulose-based biorefineries and is applied in many commercial processes. Likewise, xylanases are industrially important enzymes applied in papermaking and in the manufacture of prebiotics and pharmaceuticals. Owing to the widespread application of these enzymes, many prokaryotes and eukaryotes have been exploited to produce cellulase and xylanases in good yields, yet yeasts have rarely been explored for their plant-cell-wall-degrading activities. This review is focused on summarizing reports about cellulolytic and xylanolytic yeasts, their properties, and their biotechnological applications.
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Zhang Y, Kang X, Zhen F, Wang Z, Kong X, Sun Y. Assessment of enzyme addition strategies on the enhancement of lipid yield from microalgae. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2021.108198] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Degradation of Lignocelluloses Cocoa Shell (Theobroma cacao L.) by Various Types of Mould Treatments. J FOOD QUALITY 2021. [DOI: 10.1155/2021/6127029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Lignocellulose can be degraded by lignocellulolytic microorganisms such as moulds. The purpose of the study was to obtain the right type of moulds in degrading lignocellulose on the cocoa shell powder. The study used a completely randomized design method using four treatments of different types of mould (Trichoderma viride, Neurospora sitophila, Aspergillus niger, and Rhizopus oryzae) towards cocoa shell powder fermentation. Solid fermentation of cocoa shell powder was carried out for 5 days in an incubator with a temperature of 30°C for T. viride, N. sitophila, and R. oryzae, while A. niger of 35°C. The fermented substrate was then dried in a cabinet oven with a temperature of 50°C for 4 days. Tests of lignin, cellulose, and hemicellulose were performed towards the treatments by the Chesson method, while the moisture content test was performed using the AOAC method. Degradation of fermented cocoa shell powder has shown a significant effect on moisture, lignin, cellulose, and hemicellulose contents. Trichoderma viride resulted in the highest lignocellulose degradation compared with the other treatments. The percentage decrease of lignin content is up to 46.69 wt%; while cellulose of 22.59 wt%; and hemicellulose is about 19.41 wt% from the initial lignin weight.
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Bhardwaj N, Kumar B, Agrawal K, Verma P. Current perspective on production and applications of microbial cellulases: a review. BIORESOUR BIOPROCESS 2021; 8:95. [PMID: 38650192 PMCID: PMC10992179 DOI: 10.1186/s40643-021-00447-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 09/21/2021] [Indexed: 12/27/2022] Open
Abstract
The potential of cellulolytic enzymes has been widely studied and explored for bioconversion processes and plays a key role in various industrial applications. Cellulase, a key enzyme for cellulose-rich waste feedstock-based biorefinery, has increasing demand in various industries, e.g., paper and pulp, juice clarification, etc. Also, there has been constant progress in developing new strategies to enhance its production, such as the application of waste feedstock as the substrate for the production of individual or enzyme cocktails, process parameters control, and genetic manipulations for enzyme production with enhanced yield, efficiency, and specificity. Further, an insight into immobilization techniques has also been presented for improved reusability of cellulase, a critical factor that controls the cost of the enzyme at an industrial scale. In addition, the review also gives an insight into the status of the significant application of cellulase in the industrial sector, with its techno-economic analysis for future applications. The present review gives a complete overview of current perspectives on the production of microbial cellulases as a promising tool to develop a sustainable and greener concept for industrial applications.
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Affiliation(s)
- Nisha Bhardwaj
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India
- Department of Chemical Engineering, Institute of Chemical Technology, Nathalal Parekh Marg, Matunga, Mumbai, Maharashtra, 400019, India
| | - Bikash Kumar
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India
| | - Komal Agrawal
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India
| | - Pradeep Verma
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India.
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Tingley JP, Low KE, Xing X, Abbott DW. Combined whole cell wall analysis and streamlined in silico carbohydrate-active enzyme discovery to improve biocatalytic conversion of agricultural crop residues. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:16. [PMID: 33422151 PMCID: PMC7797155 DOI: 10.1186/s13068-020-01869-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 12/24/2020] [Indexed: 05/08/2023]
Abstract
The production of biofuels as an efficient source of renewable energy has received considerable attention due to increasing energy demands and regulatory incentives to reduce greenhouse gas emissions. Second-generation biofuel feedstocks, including agricultural crop residues generated on-farm during annual harvests, are abundant, inexpensive, and sustainable. Unlike first-generation feedstocks, which are enriched in easily fermentable carbohydrates, crop residue cell walls are highly resistant to saccharification, fermentation, and valorization. Crop residues contain recalcitrant polysaccharides, including cellulose, hemicelluloses, pectins, and lignin and lignin-carbohydrate complexes. In addition, their cell walls can vary in linkage structure and monosaccharide composition between plant sources. Characterization of total cell wall structure, including high-resolution analyses of saccharide composition, linkage, and complex structures using chromatography-based methods, nuclear magnetic resonance, -omics, and antibody glycome profiling, provides critical insight into the fine chemistry of feedstock cell walls. Furthermore, improving both the catalytic potential of microbial communities that populate biodigester reactors and the efficiency of pre-treatments used in bioethanol production may improve bioconversion rates and yields. Toward this end, knowledge and characterization of carbohydrate-active enzymes (CAZymes) involved in dynamic biomass deconstruction is pivotal. Here we overview the use of common "-omics"-based methods for the study of lignocellulose-metabolizing communities and microorganisms, as well as methods for annotation and discovery of CAZymes, and accurate prediction of CAZyme function. Emerging approaches for analysis of large datasets, including metagenome-assembled genomes, are also discussed. Using complementary glycomic and meta-omic methods to characterize agricultural residues and the microbial communities that digest them provides promising streams of research to maximize value and energy extraction from crop waste streams.
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Affiliation(s)
- Jeffrey P Tingley
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, 5403-1st Avenue South, Lethbridge, AB, T1J 4B1, Canada
- Department of Biochemistry, University of Lethbridge, Lethbridge, AB, T1K 6T5, Canada
| | - Kristin E Low
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, 5403-1st Avenue South, Lethbridge, AB, T1J 4B1, Canada
| | - Xiaohui Xing
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, 5403-1st Avenue South, Lethbridge, AB, T1J 4B1, Canada
| | - D Wade Abbott
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, 5403-1st Avenue South, Lethbridge, AB, T1J 4B1, Canada.
- Department of Biochemistry, University of Lethbridge, Lethbridge, AB, T1K 6T5, Canada.
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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: 63] [Impact Index Per Article: 15.8] [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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Haske-Cornelius O, Hartmann A, Brunner F, Pellis A, Bauer W, Nyanhongo GS, Guebitz GM. Effects of enzymes on the refining of different pulps. J Biotechnol 2020; 320:1-10. [PMID: 32553829 DOI: 10.1016/j.jbiotec.2020.06.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 05/29/2020] [Accepted: 06/09/2020] [Indexed: 11/30/2022]
Abstract
Comparative studies of the effects of two commercial enzyme formulations on fiber refining were conducted. Extensive basic characterisation of the enzymes involved, assessment of their hydrolytic activities on different model substrates as well as on different pulps (softwood sulfate, softwood sulfite, hardwood sulfate) were evaluated. Both enzyme formulations showed endoglucanase as well as some xylanase and β-glucosidase activity. In addition, Enzyme A reached a CMC end viscosity of 19.5 mPa compared to 11.1 mPa for Enzyme B. Reducing sugar release almost doubled from 695 μmol mL-1 for hardwood sulfate pulp to 1300 μmol mL-1 for softwood sulfite pulp with Enzyme B under the same conditions. Enzyme A increased the degree of refining even under non-ideal conditions from 23 °SR to up to 50 °SR. Further characterization of hand sheets, made from enzyme pre-treated and refined cellulose fibers with Enzyme A and B, showed that Enzyme A had the best effects leading to hand sheets with increased tensile strength and low air permeability. In summary, the increase in the degree of refining seen for Enzyme A correlated to higher xylanase and β-glucosidase activity and lower endoglucanase activity.
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Affiliation(s)
- Oskar Haske-Cornelius
- Institute of Environmental Biotechnology, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria
| | - Alexandra Hartmann
- Graz University of Technology, Institute of Paper, Pulp and Fiber Technology, Inffeldgasse 23, Graz, 8010, Austria
| | - Florian Brunner
- Institute of Environmental Biotechnology, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria
| | - Alessandro Pellis
- Institute of Environmental Biotechnology, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria
| | - Wolfgang Bauer
- Graz University of Technology, Institute of Paper, Pulp and Fiber Technology, Inffeldgasse 23, Graz, 8010, Austria
| | - Gibson S Nyanhongo
- Institute of Environmental Biotechnology, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria.
| | - Georg M Guebitz
- Institute of Environmental Biotechnology, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria; Austrian Centre of Industrial Biotechnology, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria
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Ren M, Wang Y, Liu G, Zuo B, Zhang Y, Wang Y, Liu W, Liu X, Zhong Y. The effects of deletion of cellobiohydrolase genes on carbon source-dependent growth and enzymatic lignocellulose hydrolysis in Trichoderma reesei. J Microbiol 2020; 58:687-695. [PMID: 32524344 DOI: 10.1007/s12275-020-9630-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 04/22/2020] [Accepted: 05/04/2020] [Indexed: 10/24/2022]
Abstract
The saprophytic fungus Trichoderma reesei has long been used as a model to study microbial degradation of lignocellulosic biomass. The major cellulolytic enzymes of T. reesei are the cellobiohydrolases CBH1 and CBH2, which constitute more than 70% of total proteins secreted by the fungus. However, their physiological functions and effects on enzymatic hydrolysis of cellulose substrates are not sufficiently elucidated. Here, the cellobiohydrolase-encoding genes cbh1 and cbh2 were deleted, individually or combinatively, by using an auxotrophic marker-recycling technique in T. reesei. When cultured on media with different soluble carbon sources, all three deletion strains (Δcbh1, Δcbh2, and Δcbh1Δcbh2) exhibited no dramatic variation in morphological phenotypes, but their growth rates increased apparently when cultured on soluble cellulase-inducing carbon sources. In addition, Δcbh1 showed dramatically reduced growth and Δcbh1Δcbh2 could hardly grew on microcrystalline cellulose (MCC), whereas all strains grew equally on sodium carboxymethyl cellulose (CMC-Na), suggesting that the influence of the CBHs on growth was carbon source-dependent. Moreover, five representative cellulose substrates were used to analyse the influence of the absence of CBHs on saccharification efficiency. CBH1 deficiency significantly affected the enzymatic hydrolysis rates of various cellulose substrates, where acid pre-treated corn stover (PCS) was influenced the least. CBH2 deficiency reduced the hydrolysis of MCC, PCS, and acid pre-treated and delignified corncob but improved the hydrolysis ability of filter paper. These results demonstrate the specific contributions of CBHs to the hydrolysis of different types of biomass, which could facilitate the development of tailor-made strains with highly efficient hydrolysis enzymes for certain biomass types in the biofuel industry.
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Affiliation(s)
- Meibin Ren
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China
| | - Yifan Wang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China
| | - Guoxin Liu
- Zibo Center Hospital, Zi Bo, 255036, P. R. China
| | - Bin Zuo
- Leling Shengli New Energy Co., Ltd., Leling, 253600, P. R. China
| | - Yuancheng Zhang
- Leling Shengli New Energy Co., Ltd., Leling, 253600, P. R. China
| | - Yunhe Wang
- Leling Shengli New Energy Co., Ltd., Leling, 253600, P. R. China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China
| | - Xiangmei Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China.
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China.
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Akram F, Haq IU. Overexpression and characterization of TnCel12B, a hyperthermophilic GH12 endo-1,4-β-glucanase cloned from Thermotoga naphthophila RKU-10 T. Anal Biochem 2020; 599:113741. [PMID: 32339490 DOI: 10.1016/j.ab.2020.113741] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 04/08/2020] [Accepted: 04/14/2020] [Indexed: 11/26/2022]
Abstract
A putative cellulolytic gene (825 bp) from Thermotoga naphthophila RKU-10T was overexpressed as an active soluble endo-1,4-β-glucanase (TnCel12B), belongs to glycoside hydrolase family 12 (GH12), in a mesophilic expression host. Heterologous expression and engineered bacterial cell mass was improved through specific strategies (induction and cultivation). Hence, intracellular activity of TnCel12B was enhanced in ZYBM9 modified medium (pH 7.0) by 8.38 and 6.25 fold with lactose (200 mM) and IPTG (0.5 mM) induction, respectively; and 6.95 fold was increased in ZYP-5052 auto-inducing medium after 8 h incubation at 26 °C (200 rev min-1). Purified TnCel12B with a molecular weight of ~32 kDa, was optimally active at 90 °C and pH 6.0; and exhibited prodigious stability over a wide range of temperature (50-85 °C) and pH (5.0-9.0) for 8 h TnCel12B displayed great resistance towards different chemical modulators, though activity was improved by Mg2+, Zn2+, Pb2+ and Ca2+. Purified TnCel12B had affinity with various substrates but peak activity was observed toward barley β-glucan (1664 U mg-1) and carboxymethyl cellulose (736 U mg-1). The values of Km, Vmax, kcat, and kcatKm-1 were found to be 4.63 mg mL-1, 916 μmol mg-1min-1, 1326.7 s-1 and 286.54 mL mg-1 s-1, respectively using CMC substrate. All noteworthy features of TnCel12B make it an appropriate industrial candidate for bioethanol production and various other potential applications.
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Affiliation(s)
- Fatima Akram
- Institute of Industrial Biotechnology, GC University, Lahore, 54000, Pakistan.
| | - Ikram Ul Haq
- Institute of Industrial Biotechnology, GC University, Lahore, 54000, Pakistan.
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12
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Aliyu H, Gorte O, Zhou X, Neumann A, Ochsenreither K. In silico Proteomic Analysis Provides Insights Into Phylogenomics and Plant Biomass Deconstruction Potentials of the Tremelalles. Front Bioeng Biotechnol 2020; 8:226. [PMID: 32318549 PMCID: PMC7147457 DOI: 10.3389/fbioe.2020.00226] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 03/05/2020] [Indexed: 01/27/2023] Open
Abstract
Basidiomycetes populate a wide range of ecological niches but unlike ascomycetes, their capabilities to decay plant polymers and their potential for biotechnological approaches receive less attention. Particularly, identification and isolation of CAZymes is of biotechnological relevance and has the potential to improve the cache of currently available commercial enzyme cocktails toward enhanced plant biomass utilization. The order Tremellales comprises phylogenetically diverse fungi living as human pathogens, mycoparasites, saprophytes or associated with insects. Here, we have employed comparative genomics approaches to highlight the phylogenomic relationships among thirty-five Tremellales and to identify putative enzymes of biotechnological interest encoded on their genomes. Evaluation of the predicted proteomes of the thirty-five Tremellales revealed 6,918 putative carbohydrate-active enzymes (CAZYmes) and 7,066 peptidases. Two soil isolates, Saitozyma podzolica DSM 27192 and Cryptococcus sp. JCM 24511, show higher numbers harboring an average of 317 compared to a range of 267-121 CAZYmes for the rest of the strains. Similarly, the proteomes of the two soil isolates along with two plant associated strains contain higher number of peptidases sharing an average of 234 peptidases compared to a range of 226-167 for the rest of the strains. Despite these huge differences and the apparent enrichment of these enzymes among the soil isolates, the data revealed a diversity of the various enzyme families that does not reflect specific habitat type. Growth experiment on various carbohydrates to validate the predictions provides support for this view. Overall, the data indicates that the Tremellales could serve as a rich source of both CAZYmes and peptidases with wide range of potential biotechnological relevance.
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Affiliation(s)
- Habibu Aliyu
- Institute of Process Engineering in Life Science 2: Technical Biology, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Olga Gorte
- Institute of Process Engineering in Life Science 2: Technical Biology, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Xinhai Zhou
- Institute of Process Engineering in Life Science 2: Technical Biology, Karlsruhe Institute of Technology, Karlsruhe, Germany
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Anke Neumann
- Institute of Process Engineering in Life Science 2: Technical Biology, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Katrin Ochsenreither
- Institute of Process Engineering in Life Science 2: Technical Biology, Karlsruhe Institute of Technology, Karlsruhe, Germany
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Hossain A, Rahaman MS, Lee D, Phung TK, Canlas CG, Simmons BA, Renneckar S, Reynolds W, George A, Tulaphol S, Sathitsuksanoh N. Enhanced Softwood Cellulose Accessibility by H 3PO 4 Pretreatment: High Sugar Yield without Compromising Lignin Integrity. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b05873] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Anwar Hossain
- Department of Chemical Engineering, University of Louisville, Louisville, Kentucky 40292, United States
| | - Mohammad Shahinur Rahaman
- Department of Chemical Engineering, University of Louisville, Louisville, Kentucky 40292, United States
| | - David Lee
- Joint BioEnergy Institute, 5885 Hollis St, Emeryville, California 94608, United States
| | - Thanh Khoa Phung
- Department of Chemical Engineering, University of Louisville, Louisville, Kentucky 40292, United States
| | - Christian G. Canlas
- King Abdullah University of Science and Technology (KAUST), Core Laboratories, Thuwal, 23955-6900 Saudi Arabia
- College of Chemistry, University of California at Berkeley, Berkeley, California 94720, United States
| | - Blake A. Simmons
- Joint BioEnergy Institute, 5885 Hollis St, Emeryville, California 94608, United States
- Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, California 94720, United States
| | - Scott Renneckar
- Faculty of Forestry, University of British Columbia, Vancouver, Canada
| | - William Reynolds
- Department of Materials Science & Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Anthe George
- Joint BioEnergy Institute, 5885 Hollis St, Emeryville, California 94608, United States
- Sandia National Laboratories, 7011 East Ave, Livermore, California 94551, United States
| | - Sarttrawut Tulaphol
- Department of Chemical Engineering, University of Louisville, Louisville, Kentucky 40292, United States
- Department of Chemistry, King Mongkut’s University of Technology Thonburi, Bangkok 10140, Thailand
| | - Noppadon Sathitsuksanoh
- Department of Chemical Engineering, University of Louisville, Louisville, Kentucky 40292, United States
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Molecular simulation of PcCel45A protein expressed from Aspergillus nidulans to understand its structure, dynamics, and thermostability. J Mol Model 2019; 25:317. [PMID: 31598788 DOI: 10.1007/s00894-019-4175-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 08/19/2019] [Indexed: 10/25/2022]
Abstract
PACS and mathematical subject classification numbers as needed. Molecular dynamic simulation is a very usable tool to understand various factors, including structure temperature dependence, dynamics, and stability for protein structure. The three main components, namely endoglucanase, exoglucanase, and β-glucosidase, effectively convert lignocellulosic biomass into fermentable sugar. Cellulose is the major component of plant cell walls and is the most abundant organic compound on the earth. Somewhat organisms can use cellulose as a food source, possessing cellulases (cellobiohydrolases and endoglucanases) that can catalyze the hydrolysis of the β-(1,4) glycosidic bonds. In this work, we investigated conformational and structural properties of PcCel45A protein by changing at temperatures with 300 K, 333 K, and 352 K. We found that the ASN92 residue was the major contributor to the stability of structure; some other residues correlated significantly with thermal stability. We also compared the theoretical results of the current study with the experimental ones published in previous studies.
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Fortune B, Mhlongo S, van Zyl LJ, Huddy R, Smart M, Trindade M. Characterisation of three novel α-L-arabinofuranosidases from a compost metagenome. BMC Biotechnol 2019; 19:22. [PMID: 30999885 PMCID: PMC6472066 DOI: 10.1186/s12896-019-0510-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 03/13/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The importance of the accessory enzymes such as α-L-arabinofuranosidases (AFases) in synergistic interactions within cellulolytic mixtures has introduced a paradigm shift in the search for hydrolytic enzymes. The aim of this study was to characterize novel AFase genes encoding enzymes with differing temperature optima and thermostabilities for use in hydrolytic cocktails. RESULTS Three fosmids, pFos-H4, E3 and D3 were selected from the cloned metagenome of high temperature compost, expressed in Escherichia coli and subsequently purified to homogeneity from cell lysate. All the AFases were clustered within the GH51 AFase family and shared a homo-hexameric structure. Both AFase-E3 and H4 showed optimal activity at 60 °C while AFase-D3 had unique properties as it showed optimal activity at 25 °C as well as the ability to maintain substantial activity at temperatures as high as 90 °C. However, AFase-E3 was the most thermostable amongst the three AFases showing full activity even at 70 °C. The maximum activity was observed at a pH profile between pH 4.0-6.0 for all three AFases with optimal activity for AFase H4, D3 and E3 at pH 5.0, 4.5 and 4.0, respectively. All the AFases showed KM range between 0.31 mM and 0.43 mM, Kcat range between 131 s- 1 and 219 s- 1 and the specific activity for AFase-H4, AFases-E3 and was 143, 228 and 175 U/mg, respectively. AFases-E3 and D3 displayed activities against pNP-β-L-arabinopyranoside and pNP-β-L-mannopyranoside respectively, and both hydrolysed pNP-β-D-glucopyranoside. CONCLUSION All three AFases displayed different biochemical characteristics despite all showing conserved overall structural similarity with typical domains of AFases belonging to GH51 family. The hydrolysis of cellobiose by a GH51 family AFase is demonstrated for the first time in this study.
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Affiliation(s)
- Brent Fortune
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Bellville, South Africa
| | - Sizwe Mhlongo
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Bellville, South Africa
| | - Leonardo Joaquim van Zyl
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Bellville, South Africa
| | - Robert Huddy
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Bellville, South Africa.,Centre for Bioprocess Engineering Research, University of Cape Town, Cape Town, Western Cape, South Africa
| | - Mariette Smart
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Bellville, South Africa.,Centre for Bioprocess Engineering Research, University of Cape Town, Cape Town, Western Cape, South Africa
| | - Marla Trindade
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Bellville, South Africa.
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An Insight into Fungal Cellulases and Their Industrial Applications. Fungal Biol 2019. [DOI: 10.1007/978-3-030-14726-6_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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17
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Du J, Zhang X, Li X, Zhao J, Liu G, Gao B, Qu Y. The cellulose binding region in Trichoderma reesei cellobiohydrolase I has a higher capacity in improving crystalline cellulose degradation than that of Penicillium oxalicum. BIORESOURCE TECHNOLOGY 2018; 266:19-25. [PMID: 29940438 DOI: 10.1016/j.biortech.2018.06.050] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 06/16/2018] [Accepted: 06/18/2018] [Indexed: 06/08/2023]
Abstract
Commercial cellulase preparations for lignocellulose bioconversion are mainly produced by the fungus Trichoderma reesei. The maximum cellulose conversion of T. reesei cellulase mixture was 15%-20% higher than that of Penicillium oxalicum in the hydrolysis of corncob residue and Avicel. Nevertheless, both preparations hydrolyzed more than 92% of cellulose in NaOH-mercerized Avicel. When added to Avicel hydrolysis residue that was less reactive to P. oxalicum cellulases, cellobiohydrolase I (CBH I) from T. reesei resulted in a higher cellulose conversion than its homologous proteins from P. oxalicum and Aspergillus niger at the same protein loadings. Further domain exchange experiment attributed the high hydrolytic efficiency of T. reesei CBH I to its inter-domain linker and cellulose-binding domain. The results in part explained the superior performance of T. reesei cellulases on the degradation of native crystalline cellulose, and highlighted the important role of cellulose-binding region in determining the degree of hydrolysis by cellulases.
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Affiliation(s)
- Jian Du
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, Shandong, PR China
| | - Xiu Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, Shandong, PR China
| | - Xuezhi Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, Shandong, PR China
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, Shandong, PR China
| | - Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, Shandong, PR China; Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, Shandong, PR China.
| | - Baoyu Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, Shandong, PR China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, Shandong, PR China; National Glycoengineering Research Center, Shandong University, Qingdao 266237, Shandong, PR China
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Birhade S, Pednekar M, Sagwal S, Odaneth A, Lali A. Preparation of cellulase concoction using differential adsorption phenomenon. Prep Biochem Biotechnol 2017; 47:520-529. [PMID: 28045609 DOI: 10.1080/10826068.2016.1275009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Controlled depolymerization of cellulose is essential for the production of valuable cellooligosaccharides and cellobiose from lignocellulosic biomass. However, enzymatic cellulose hydrolysis involves multiple synergistically acting enzymes, making difficult to control the depolymerization process and generate desired product. This work exploits the varying adsorption properties of the cellulase components to the cellulosic substrate and aims to control the enzyme activity. Cellulase adsorption was favored on pretreated cellulosic biomass as compared to synthetic cellulose. Preferential adsorption of exocellulases was observed over endocellulase, while β-glucosidases remained unadsorbed. Adsorbed enzyme fraction with bound exocellulases when used for hydrolysis generated cellobiose predominantly, while the unadsorbed enzymes in the liquid fraction produced cellooligosaccharides majorly, owing to its high endocellulases activity. Thus, the differential adsorption phenomenon of the cellulase components can be used for the controlling cellulose hydrolysis for the production of an array of sugars.
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Affiliation(s)
- Sachinkumar Birhade
- a DBT-ICT Centre of Energy Biosciences , Institute of Chemical Technology, Nathalal Parikh Marg, Matunga , Mumbai , Maharashtra , India
| | - Mukesh Pednekar
- a DBT-ICT Centre of Energy Biosciences , Institute of Chemical Technology, Nathalal Parikh Marg, Matunga , Mumbai , Maharashtra , India
| | - Shilpa Sagwal
- a DBT-ICT Centre of Energy Biosciences , Institute of Chemical Technology, Nathalal Parikh Marg, Matunga , Mumbai , Maharashtra , India
| | - Annamma Odaneth
- a DBT-ICT Centre of Energy Biosciences , Institute of Chemical Technology, Nathalal Parikh Marg, Matunga , Mumbai , Maharashtra , India
| | - Arvind Lali
- a DBT-ICT Centre of Energy Biosciences , Institute of Chemical Technology, Nathalal Parikh Marg, Matunga , Mumbai , Maharashtra , India
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19
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Jain KK, Kumar S, Deswal D, Kuhad RC. Improved Production of Thermostable Cellulase from Thermoascus aurantiacus RCKK by Fermentation Bioprocessing and Its Application in the Hydrolysis of Office Waste Paper, Algal Pulp, and Biologically Treated Wheat Straw. Appl Biochem Biotechnol 2016; 181:784-800. [DOI: 10.1007/s12010-016-2249-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 09/13/2016] [Indexed: 12/15/2022]
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20
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Moraïs S, Stern J, Kahn A, Galanopoulou AP, Yoav S, Shamshoum M, Smith MA, Hatzinikolaou DG, Arnold FH, Bayer EA. Enhancement of cellulosome-mediated deconstruction of cellulose by improving enzyme thermostability. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:164. [PMID: 27493686 PMCID: PMC4973527 DOI: 10.1186/s13068-016-0577-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Accepted: 07/27/2016] [Indexed: 05/25/2023]
Abstract
BACKGROUND The concerted action of three complementary cellulases from Clostridium thermocellum, engineered to be stable at elevated temperatures, was examined on a cellulosic substrate and compared to that of the wild-type enzymes. Exoglucanase Cel48S and endoglucanase Cel8A, both key elements of the natural cellulosome from this bacterium, were engineered previously for increased thermostability, either by SCHEMA, a structure-guided, site-directed protein recombination method, or by consensus-guided mutagenesis combined with random mutagenesis using error-prone PCR, respectively. A thermostable β-glucosidase BglA mutant was also selected from a library generated by error-prone PCR that will assist the two cellulases in their methodic deconstruction of crystalline cellulose. The effects of a thermostable scaffoldin versus those of a largely mesophilic scaffoldin were also examined. By improving the stability of the enzyme subunits and the structural component, we aimed to improve cellulosome-mediated deconstruction of cellulosic substrates. RESULTS The results demonstrate that the combination of thermostable enzymes as free enzymes and a thermostable scaffoldin was more active on the cellulosic substrate than the wild-type enzymes. Significantly, "thermostable" designer cellulosomes exhibited a 1.7-fold enhancement in cellulose degradation compared to the action of conventional designer cellulosomes that contain the respective wild-type enzymes. For designer cellulosome formats, the use of the thermostabilized scaffoldin proved critical for enhanced enzymatic performance under conditions of high temperatures. CONCLUSIONS Simple improvement in the activity of a given enzyme does not guarantee its suitability for use in an enzyme cocktail or as a designer cellulosome component. The true merit of improvement resides in its ultimate contribution to synergistic action, which can only be determined experimentally. The relevance of the mutated thermostable enzymes employed in this study as components in multienzyme systems has thus been confirmed using designer cellulosome technology. Enzyme integration via a thermostable scaffoldin is critical to the ultimate stability of the complex at higher temperatures. Engineering of thermostable cellulases and additional lignocellulosic enzymes may prove a determinant parameter for development of state-of-the-art designer cellulosomes for their employment in the conversion of cellulosic biomass to soluble sugars.Graphical abstractConversion of conventional designer cellulosomes into thermophilic designer cellulosomes.
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Affiliation(s)
- Sarah Moraïs
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Johanna Stern
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Amaranta Kahn
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Anastasia P. Galanopoulou
- Microbiology Group, Faculty of Biology, National and Kapodistrian University of Athens, Zografou Campus, 15784 Athens, Greece
| | - Shahar Yoav
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
- Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, P.O. Box 12, 76100 Rehovot, Israel
| | - Melina Shamshoum
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Matthew A. Smith
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | - Dimitris G. Hatzinikolaou
- Microbiology Group, Faculty of Biology, National and Kapodistrian University of Athens, Zografou Campus, 15784 Athens, Greece
| | - Frances H. Arnold
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | - Edward A. Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
- Department of Biological Chemistry, The Weizmann Institute of Science, 76100 Rehovot, Israel
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21
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Singh B, Poças-Fonseca MJ, Johri BN, Satyanarayana T. Thermophilic molds: Biology and applications. Crit Rev Microbiol 2016; 42:985-1006. [DOI: 10.3109/1040841x.2015.1122572] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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22
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Gomes E, de Souza AR, Orjuela GL, Da Silva R, de Oliveira TB, Rodrigues A. Applications and Benefits of Thermophilic Microorganisms and Their Enzymes for Industrial Biotechnology. Fungal Biol 2016. [DOI: 10.1007/978-3-319-27951-0_21] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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23
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Nag A, Sprague MA, Griggs AJ, Lischeske JJ, Stickel JJ, Mittal A, Wang W, Johnson DK. Parameter determination and validation for a mechanistic model of the enzymatic saccharification of cellulose-Iβ. Biotechnol Prog 2015; 31:1237-48. [PMID: 26081044 DOI: 10.1002/btpr.2122] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/08/2015] [Indexed: 11/08/2022]
Affiliation(s)
- Ambarish Nag
- Computational Science Center; National Renewable Energy Laboratory; 15013 Denver West Parkway Golden CO 80401
| | - Michael A. Sprague
- Computational Science Center; National Renewable Energy Laboratory; 15013 Denver West Parkway Golden CO 80401
| | - Andrew J. Griggs
- National Bioenergy Center; National Renewable Energy Laboratory; 15013 Denver West Parkway Golden CO 80401
| | - James J. Lischeske
- National Bioenergy Center; National Renewable Energy Laboratory; 15013 Denver West Parkway Golden CO 80401
| | - Jonathan J. Stickel
- National Bioenergy Center; National Renewable Energy Laboratory; 15013 Denver West Parkway Golden CO 80401
| | - Ashutosh Mittal
- Biosciences Center; National Renewable Energy Laboratory; 15013 Denver West Parkway Golden CO 80401
| | - Wei Wang
- Biosciences Center; National Renewable Energy Laboratory; 15013 Denver West Parkway Golden CO 80401
| | - David K. Johnson
- Biosciences Center; National Renewable Energy Laboratory; 15013 Denver West Parkway Golden CO 80401
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24
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Zoglowek M, Lübeck PS, Ahring BK, Lübeck M. Heterologous expression of cellobiohydrolases in filamentous fungi – An update on the current challenges, achievements and perspectives. Process Biochem 2015. [DOI: 10.1016/j.procbio.2014.12.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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25
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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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Production of thermostable hydrolases (cellulases and xylanase) from Thermoascus aurantiacus RCKK: a potential fungus. Bioprocess Biosyst Eng 2014; 38:787-96. [DOI: 10.1007/s00449-014-1320-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 10/26/2014] [Indexed: 10/24/2022]
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Rahikainen JL, Evans JD, Mikander S, Kalliola A, Puranen T, Tamminen T, Marjamaa K, Kruus K. Cellulase–lignin interactions—The role of carbohydrate-binding module and pH in non-productive binding. Enzyme Microb Technol 2013; 53:315-21. [DOI: 10.1016/j.enzmictec.2013.07.003] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 07/04/2013] [Accepted: 07/08/2013] [Indexed: 11/17/2022]
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Structural characterization of a unique marine animal family 7 cellobiohydrolase suggests a mechanism of cellulase salt tolerance. Proc Natl Acad Sci U S A 2013; 110:10189-94. [PMID: 23733951 DOI: 10.1073/pnas.1301502110] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Nature uses a diversity of glycoside hydrolase (GH) enzymes to convert polysaccharides to sugars. As lignocellulosic biomass deconstruction for biofuel production remains costly, natural GH diversity offers a starting point for developing industrial enzymes, and fungal GH family 7 (GH7) cellobiohydrolases, in particular, provide significant hydrolytic potential in industrial mixtures. Recently, GH7 enzymes have been found in other kingdoms of life besides fungi, including in animals and protists. Here, we describe the in vivo spatial expression distribution, properties, and structure of a unique endogenous GH7 cellulase from an animal, the marine wood borer Limnoria quadripunctata (LqCel7B). RT-quantitative PCR and Western blot studies show that LqCel7B is expressed in the hepatopancreas and secreted into the gut for wood degradation. We produced recombinant LqCel7B, with which we demonstrate that LqCel7B is a cellobiohydrolase and obtained four high-resolution crystal structures. Based on a crystallographic and computational comparison of LqCel7B to the well-characterized Hypocrea jecorina GH7 cellobiohydrolase, LqCel7B exhibits an extended substrate-binding motif at the tunnel entrance, which may aid in substrate acquisition and processivity. Interestingly, LqCel7B exhibits striking surface charges relative to fungal GH7 enzymes, which likely results from evolution in marine environments. We demonstrate that LqCel7B stability and activity remain unchanged, or increase at high salt concentration, and that the L. quadripunctata GH mixture generally contains cellulolytic enzymes with highly acidic surface charge compared with enzymes derived from terrestrial microbes. Overall, this study suggests that marine cellulases offer significant potential for utilization in high-solids industrial biomass conversion processes.
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A simple and fast method for the determination of endo- and exo-cellulase activity in cellulase preparations using filter paper. Enzyme Microb Technol 2012; 51:280-5. [DOI: 10.1016/j.enzmictec.2012.07.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Revised: 06/22/2012] [Accepted: 07/23/2012] [Indexed: 11/17/2022]
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30
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Komor RS, Romero PA, Xie CB, Arnold FH. Highly thermostable fungal cellobiohydrolase I (Cel7A) engineered using predictive methods. Protein Eng Des Sel 2012; 25:827-33. [PMID: 22961332 DOI: 10.1093/protein/gzs058] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Building on our previous efforts to generate thermostable chimeric fungal cellobiohydrolase I (CBH I, also known as Cel7A) cellulases by structure-guided recombination, we used FoldX and a 'consensus' sequence approach to identify individual mutations present in the five homologous parent CBH I enzymes which further stabilize the chimeras. Using the FoldX force field, we calculated the effect on ΔG(Folding) of each candidate mutation in a number of CBH I structures and chose those predicted to be stabilizing in multiple structures. With an alignment of 41 CBH I sequences, we also used amino acid frequencies at each candidate position to calculate predicted effects on ΔG(Folding). A combination of mutations chosen using these methods increased the T(50) of the most thermostable chimera by an additional 4.7°C, to yield a CBH I with T(50) of 72.1°C, which is 9.2°C higher than that of the most stable native CBH I, from Talaromyces emersonii. This increased stability resulted in a 10°C increase in the optimal temperature for activity, to 65°C, and a 50% increase in total sugar production from crystalline cellulose at the optimal temperature, compared with native T.emersonii CBH I.
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Affiliation(s)
- Russell S Komor
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
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Thompson AJ, Heu T, Shaghasi T, Benyamino R, Jones A, Friis EP, Wilson KS, Davies GJ. Structure of the catalytic core module of theChaetomium thermophilumfamily GH6 cellobiohydrolase Cel6A. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2012; 68:875-82. [DOI: 10.1107/s0907444912016496] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Accepted: 04/16/2012] [Indexed: 11/11/2022]
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Zou G, Shi S, Jiang Y, van den Brink J, de Vries RP, Chen L, Zhang J, Ma L, Wang C, Zhou Z. Construction of a cellulase hyper-expression system in Trichoderma reesei by promoter and enzyme engineering. Microb Cell Fact 2012; 11:21. [PMID: 22314137 PMCID: PMC3342899 DOI: 10.1186/1475-2859-11-21] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Accepted: 02/08/2012] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Trichoderma reesei is the preferred organism for producing industrial cellulases. However, a more efficient heterologous expression system for enzymes from different organism is needed to further improve its cellulase mixture. The strong cbh1 promoter of T. reesei is frequently used in heterologous expression, however, the carbon catabolite repressor CREI may reduce its strength by binding to the cbh1 promoter at several binding sites. Another crucial point to enhance the production of heterologous enzymes is the stability of recombinant mRNA and the prevention of protein degradation within the endoplasmic reticulum, especially for the bacteria originated enzymes.In this study, the CREI binding sites within the cbh1 promoter were replaced with the binding sites of transcription activator ACEII and the HAP2/3/5 complex to improve the promoter efficiency. To further improve heterologous expression efficiency of bacterial genes within T. reesei, a flexible polyglycine linker and a rigid α-helix linker were tested in the construction of fusion genes between cbh1 from T. reesei and e1, encoding an endoglucanase from Acidothermus cellulolyticus. RESULTS The modified promoter resulted in an increased expression level of the green fluorescent protein reporter by 5.5-fold in inducing culture medium and 7.4-fold in repressing culture medium. The fusion genes of cbh1 and e1 were successfully expressed in T. reesei under the control of promoter pcbh1m2. The higher enzyme activities and thermostability of the fusion protein with rigid linker indicated that the rigid linker might be more suitable for the heterologous expression system in T. reesei. Compared to the parent strain RC30-8, the FPase and CMCase activities of the secreted enzyme mixture from the corresponding transformant R1 with the rigid linker increased by 39% and 30% at 60°C, respectively, and the reduced sugar concentration in the hydrolysate of pretreated corn stover (PCS) was dramatically increased by 40% at 55°C and 169% at 60°C when its enzyme mixture was used in the hydrolysis. CONCLUSIONS This study shows that optimizations of the promoter and linker for hybrid genes can dramatically improve the efficiency of heterologous expression of cellulase genes in T. reesei.
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Affiliation(s)
- Gen Zou
- Chinese Academy of Sciences, Shanghai, China.
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Li DC, Li AN, Papageorgiou AC. Cellulases from thermophilic fungi: recent insights and biotechnological potential. Enzyme Res 2011; 2011:308730. [PMID: 22145076 PMCID: PMC3226318 DOI: 10.4061/2011/308730] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 09/05/2011] [Accepted: 09/07/2011] [Indexed: 11/24/2022] Open
Abstract
Thermophilic fungal cellulases are promising enzymes in protein engineering efforts aimed at optimizing industrial processes, such as biomass degradation and biofuel production. The cloning and expression in recent years of new cellulase genes from thermophilic fungi have led to a better understanding of cellulose degradation in these species. Moreover, crystal structures of thermophilic fungal cellulases are now available, providing insights into their function and stability. The present paper is focused on recent progress in cloning, expression, regulation, and structure of thermophilic fungal cellulases and the current research efforts to improve their properties for better use in biotechnological applications.
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Affiliation(s)
- Duo-Chuan Li
- Department of Environmental Biology, Shandong Agricultural University, Taian, Shandong 271018, China
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Alternatives to Trichoderma reesei in biofuel production. Trends Biotechnol 2011; 29:419-25. [DOI: 10.1016/j.tibtech.2011.04.004] [Citation(s) in RCA: 201] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 04/07/2011] [Accepted: 04/12/2011] [Indexed: 10/18/2022]
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Wang CP, Wu JZ, Sun HW, Wang T, Liu HB, Chang Y. Adsorption of Pb(II) Ion from Aqueous Solutions by Tourmaline as a Novel Adsorbent. Ind Eng Chem Res 2011. [DOI: 10.1021/ie102520w] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- C. P. Wang
- MOE Key Laboratory of Pollution Process and Environmental Criteria, College of Environment Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - J. Z. Wu
- MOE Key Laboratory of Pollution Process and Environmental Criteria, College of Environment Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - H. W. Sun
- MOE Key Laboratory of Pollution Process and Environmental Criteria, College of Environment Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - T. Wang
- MOE Key Laboratory of Pollution Process and Environmental Criteria, College of Environment Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - H. B. Liu
- MOE Key Laboratory of Pollution Process and Environmental Criteria, College of Environment Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - Y. Chang
- MOE Key Laboratory of Pollution Process and Environmental Criteria, College of Environment Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
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Ng IS, Tsai SW, Ju YM, Yu SM, Ho THD. Dynamic synergistic effect on Trichoderma reesei cellulases by novel β-glucosidases from Taiwanese fungi. BIORESOURCE TECHNOLOGY 2011; 102:6073-81. [PMID: 21377353 DOI: 10.1016/j.biortech.2010.12.110] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Revised: 12/28/2010] [Accepted: 12/30/2010] [Indexed: 05/02/2023]
Abstract
Dynamic synergistic effects in cellulosic bioconversion have been revealed between Trichoderma reesei cellulases and β-glucosidases (BGLs) from six Taiwanese fungi. A high level of synergy (8.9-fold) was observed with the addition of Chaetomella raphigera BGL to T. reesei cellulases. In addition, the C. raphigera BGL possessed the highest activity (V(max)/K(m)=46.6 U/mg mM) and lowest glucose inhibition (Ki=4.6mM) with the substrate 4-nitrophenyl β-d-glucopyranoside. For the natural cellobiose substrate, however, the previously isolated Aspergillus niger BGL Novo-188 had the highest V(max)/K(m) (0.72 U/mg mM) and lowest Ki (59.5mM). The demonstrated dynamic synergistic effects between some BGLs and the T. reesei cellulase system suggest that BGLs not only prevent the inhibition by cellobiose, but also enhance activities of endo- and exo-cellulases in cellulosic bioconversion. Comparisons of kinetic parameters and synergism analyses between BGLs and T. reesei cellulases can be used for further optimization of the cellulosic bioconversion process.
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Affiliation(s)
- I-Son Ng
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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37
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Park S, Baker JO, Himmel ME, Parilla PA, Johnson DK. Cellulose crystallinity index: measurement techniques and their impact on interpreting cellulase performance. BIOTECHNOLOGY FOR BIOFUELS 2010; 3:10. [PMID: 20497524 PMCID: PMC2890632 DOI: 10.1186/1754-6834-3-10] [Citation(s) in RCA: 1148] [Impact Index Per Article: 82.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Accepted: 05/24/2010] [Indexed: 05/02/2023]
Abstract
Although measurements of crystallinity index (CI) have a long history, it has been found that CI varies significantly depending on the choice of measurement method. In this study, four different techniques incorporating X-ray diffraction and solid-state 13C nuclear magnetic resonance (NMR) were compared using eight different cellulose preparations. We found that the simplest method, which is also the most widely used, and which involves measurement of just two heights in the X-ray diffractogram, produced significantly higher crystallinity values than did the other methods. Data in the literature for the cellulose preparation used (Avicel PH-101) support this observation. We believe that the alternative X-ray diffraction (XRD) and NMR methods presented here, which consider the contributions from amorphous and crystalline cellulose to the entire XRD and NMR spectra, provide a more accurate measure of the crystallinity of cellulose. Although celluloses having a high amorphous content are usually more easily digested by enzymes, it is unclear, based on studies published in the literature, whether CI actually provides a clear indication of the digestibility of a cellulose sample. Cellulose accessibility should be affected by crystallinity, but is also likely to be affected by several other parameters, such as lignin/hemicellulose contents and distribution, porosity, and particle size. Given the methodological dependency of cellulose CI values and the complex nature of cellulase interactions with amorphous and crystalline celluloses, we caution against trying to correlate relatively small changes in CI with changes in cellulose digestibility. In addition, the prediction of cellulase performance based on low levels of cellulose conversion may not include sufficient digestion of the crystalline component to be meaningful.
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Affiliation(s)
- Sunkyu Park
- Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA
- Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA
| | - John O Baker
- Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA
| | - Michael E Himmel
- Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA
| | - Philip A Parilla
- National Center for Photovoltaics, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA
| | - David K Johnson
- Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA
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Yeoman CJ, Han Y, Dodd D, Schroeder CM, Mackie RI, Cann IKO. Thermostable enzymes as biocatalysts in the biofuel industry. ADVANCES IN APPLIED MICROBIOLOGY 2010; 70:1-55. [PMID: 20359453 DOI: 10.1016/s0065-2164(10)70001-0] [Citation(s) in RCA: 173] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Lignocellulose is the most abundant carbohydrate source in nature and represents an ideal renewable energy source. Thermostable enzymes that hydrolyze lignocellulose to its component sugars have significant advantages for improving the conversion rate of biomass over their mesophilic counterparts. We review here the recent literature on the development and use of thermostable enzymes for the depolymerization of lignocellulosic feedstocks for biofuel production. Furthermore, we discuss the protein structure, mechanisms of thermostability, and specific strategies that can be used to improve the thermal stability of lignocellulosic biocatalysts.
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Affiliation(s)
- Carl J Yeoman
- Institute for Genomic Biology, University of Illinois, Urbana, Illinois, USA
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Hall M, Bansal P, Lee JH, Realff MJ, Bommarius AS. Cellulose crystallinity - a key predictor of the enzymatic hydrolysis rate. FEBS J 2010; 277:1571-82. [DOI: 10.1111/j.1742-4658.2010.07585.x] [Citation(s) in RCA: 408] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Bansal P, Hall M, Realff MJ, Lee JH, Bommarius AS. Modeling cellulase kinetics on lignocellulosic substrates. Biotechnol Adv 2009; 27:833-848. [DOI: 10.1016/j.biotechadv.2009.06.005] [Citation(s) in RCA: 302] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Revised: 06/19/2009] [Accepted: 06/20/2009] [Indexed: 11/15/2022]
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A family of thermostable fungal cellulases created by structure-guided recombination. Proc Natl Acad Sci U S A 2009; 106:5610-5. [PMID: 19307582 DOI: 10.1073/pnas.0901417106] [Citation(s) in RCA: 170] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
SCHEMA structure-guided recombination of 3 fungal class II cellobiohydrolases (CBH II cellulases) has yielded a collection of highly thermostable CBH II chimeras. Twenty-three of 48 genes sampled from the 6,561 possible chimeric sequences were secreted by the Saccharomyces cerevisiae heterologous host in catalytically active form. Five of these chimeras have half-lives of thermal inactivation at 63 degrees C that are greater than the most stable parent, CBH II enzyme from the thermophilic fungus Humicola insolens, which suggests that this chimera collection contains hundreds of highly stable cellulases. Twenty-five new sequences were designed based on mathematical modeling of the thermostabilities for the first set of chimeras. Ten of these sequences were expressed in active form; all 10 retained more activity than H. insolens CBH II after incubation at 63 degrees C. The total of 15 validated thermostable CBH II enzymes have high sequence diversity, differing from their closest natural homologs at up to 63 amino acid positions. Selected purified thermostable chimeras hydrolyzed phosphoric acid swollen cellulose at temperatures 7 to 15 degrees C higher than the parent enzymes. These chimeras also hydrolyzed as much or more cellulose than the parent CBH II enzymes in long-time cellulose hydrolysis assays and had pH/activity profiles as broad, or broader than, the parent enzymes. Generating this group of diverse, thermostable fungal CBH II chimeras is the first step in building an inventory of stable cellulases from which optimized enzyme mixtures for biomass conversion can be formulated.
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