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Kim IJ, Jeong D, Kim SR. Upstream processes of citrus fruit waste biorefinery for complete valorization. BIORESOURCE TECHNOLOGY 2022; 362:127776. [PMID: 35970501 DOI: 10.1016/j.biortech.2022.127776] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
Citrus fruit waste (CW) is a useful biomass and its valorization into fuels and biochemicals has received much attention. For economic feasibility, increased efficiency of the preceding extraction and enzyme saccharification processes is necessary. However, at present, there is a lack of systematic reviews addressing these two integral upstream processes in concert for CW biorefinery. Here, the state-of-the-art advancements in enzyme extraction and saccharification processes-using which relevant essential oils, flavonoids, and sugars can be obtained-are reviewed. Specifically, the extraction options for two commercially available CW-derived products, essential oils and pectin, are discussed. With respect to enzyme saccharification, the use of an undefined commercial mixture routinely results in suboptimal sugar production. In this respect, applicable strategies for enzyme mixture customization are suggested for maximizing the hydrolytic efficiency of CW. The enzyme degradation system for CW-derived carbohydrates and its extensive application for sugar production are also discussed.
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Affiliation(s)
- In Jung Kim
- Department of Applied Biosciences, Graduate School, Kyungpook National University, Daegu 41566, Korea
| | - Deokyeol Jeong
- School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Korea
| | - Soo Rin Kim
- School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Korea; Research Institute of Tailored Food Technology, Kyungpook National University, Daegu 41566, Korea.
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2
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Procópio DP, Kendrick E, Goldbeck R, Damasio ARDL, Franco TT, Leak DJ, Jin YS, Basso TO. Xylo-Oligosaccharide Utilization by Engineered Saccharomyces cerevisiae to Produce Ethanol. Front Bioeng Biotechnol 2022; 10:825981. [PMID: 35242749 PMCID: PMC8886126 DOI: 10.3389/fbioe.2022.825981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/18/2022] [Indexed: 11/26/2022] Open
Abstract
The engineering of xylo-oligosaccharide-consuming Saccharomyces cerevisiae strains is a promising approach for more effective utilization of lignocellulosic biomass and the development of economic industrial fermentation processes. Extending the sugar consumption range without catabolite repression by including the metabolism of oligomers instead of only monomers would significantly improve second-generation ethanol production This review focuses on different aspects of the action mechanisms of xylan-degrading enzymes from bacteria and fungi, and their insertion in S. cerevisiae strains to obtain microbial cell factories able of consume these complex sugars and convert them to ethanol. Emphasis is given to different strategies for ethanol production from both extracellular and intracellular xylo-oligosaccharide utilization by S. cerevisiae strains. The suitability of S. cerevisiae for ethanol production combined with its genetic tractability indicates that it can play an important role in xylan bioconversion through the heterologous expression of xylanases from other microorganisms.
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Affiliation(s)
- Dielle Pierotti Procópio
- Department of Chemical Engineering, Escola Politécnica, University of São Paulo, São Paulo, Brazil
| | - Emanuele Kendrick
- Department of Biology and Biochemistry, Faculty of Sciences, University of Bath, Bath, United Kingdom
| | - Rosana Goldbeck
- School of Food Engineering, University of Campinas, Campinas, Brazil
| | | | - Telma Teixeira Franco
- Interdisciplinary Center of Energy Planning, University of Campinas, Campinas, Brazil
- School of Chemical Engineering, University of Campinas, Campinas, Brazil
| | - David J. Leak
- Department of Biology and Biochemistry, Faculty of Sciences, University of Bath, Bath, United Kingdom
| | - Yong-Su Jin
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Department of Food Science and Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Thiago Olitta Basso
- Department of Chemical Engineering, Escola Politécnica, University of São Paulo, São Paulo, Brazil
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Neis A, da Silva Pinto L. Glycosyl hydrolases family 5, subfamily 5: Relevance and structural insights for designing improved biomass degrading cocktails. Int J Biol Macromol 2021; 193:980-995. [PMID: 34666133 DOI: 10.1016/j.ijbiomac.2021.10.062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 09/29/2021] [Accepted: 10/05/2021] [Indexed: 10/20/2022]
Abstract
Endoglucanases are carbohydrate-degrading enzymes widely used for bioethanol production as part of the enzymatic cocktail. However, family 5 subfamily 5 (GH5_5) endoglucanases are still poorly explored in depth. The Trichoderma reesei representative is the most studied enzyme, presenting catalytic activity in acidic media and mild temperature conditions. Though biochemically similar, its modular structure and synergy with other components vary greatly compared to other GH5_5 members and there is still a lack of specific studies regarding their interaction with other cellulases and application on novel and better mixtures. In this regard, the threedimensional structure elucidation is a highly valuable tool to both uncover basic catalytic mechanisms and implement engineering techniques, proved by the high success rate GH5_5 endoglucanases show. GH5_5 enzymes must be carefully evaluated to fully uncover their potential in biomass-degrading cocktails: the optimal industrial conditions, synergy with other cellulases, structural studies, and enzyme engineering approaches. We aimed to provide the current understanding of these main topics, collecting all available information about characterized GH5_5 endoglucanases function, structure, and bench experiments, in order to suggest future directions to a better application of these enzymes in the industry.
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Affiliation(s)
- Alessandra Neis
- Laboratório de Bioinformática e Proteômica (BioPro Lab), Centro de Desenvolvimento Tecnológico, Campus Universitário, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, Caixa Postal 96010-900, Brazil.
| | - Luciano da Silva Pinto
- Laboratório de Bioinformática e Proteômica (BioPro Lab), Centro de Desenvolvimento Tecnológico, Campus Universitário, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, Caixa Postal 96010-900, Brazil.
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Chandrakant Khaire K, Suryakant Moholkar V, Goyal A. Alkaline pretreatment and response surface methodology based recombinant enzymatic saccharification and fermentation of sugarcane tops. BIORESOURCE TECHNOLOGY 2021; 341:125837. [PMID: 34461408 DOI: 10.1016/j.biortech.2021.125837] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 08/20/2021] [Accepted: 08/21/2021] [Indexed: 06/13/2023]
Abstract
In present study, the water-soluble extractives removal prior to alkali pretreatment of sugarcane tops (SCT) was carried out. The solid alkali pretreated SCT (apSCT) recovered on Field-emission scanning electron microscopy (FE-SEM) analysis showed exposure of cellulosic fibres as compared with raw SCT. The analyses of apSCT by Fourier Transform Infrared (FT-IR) Spectroscopy, X-ray diffraction (XRD) and High performance liquid chromatography (HPLC) analysis also confirmed the enhanced cellulose content in apSCT. Optimum conditions for response surface methodology based saccharification of apSCT at 40 °C, 150 rpm were 2.14% (w/v) apSCT loading in citrate-phosphate buffer (50 mM, pH 6.0), recombinant hydrolytic enzymes (from Clostridium/Hungateiclostridium thermocellum) loading for endo-1,4-β-glucanase (CtCel8A) = 213.2 U/g, cellobiohydrolase (CtCBH5A) = 272.5 U/g and β-glucosidase (HtBg1) = 299.8 U/g for 49.2 h. Under optimized saccharification conditions, the total reducing sugar yield was 265 mg/g (glucose 214 mg/g) of apSCT. Fermentation of produced glucose by S. cerevisiae gave 0.19 g/g glucose of bioethanol.
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Affiliation(s)
- Kaustubh Chandrakant Khaire
- School of Energy Science and Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Vijayanand Suryakant Moholkar
- School of Energy Science and Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India; Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Arun Goyal
- School of Energy Science and Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India; Carbohydrate Enzyme Biotechnology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
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Gao W, Li Z, Liu T, Wang Y. Production of high-concentration fermentable sugars from lignocellulosic biomass by using high solids fed-batch enzymatic hydrolysis. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108186] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Lan Q, Duan Y, Wu P, Li X, Yu Y, Shi B, Zhou J, Lu H. Coordinately express hemicellulolytic enzymes in Kluyveromyces marxianus to improve the saccharification and ethanol production from corncobs. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:220. [PMID: 34809677 PMCID: PMC8607645 DOI: 10.1186/s13068-021-02070-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 11/10/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Hemicellulose acts as one factor contributing to the recalcitrance of lignocellulose that prevents cellulases to degrade the cellulose efficiently even in low quantities. Supplement of hemicellulases can enhance the performance of commercial cellulases in the enzymatic hydrolyses of lignocellulose. Kluyveromyce marxianus is an attractive yeast for cellulosic ethanol fermentation, as well as a promising host for heterologous protein production, since it has remarkable thermotolerance, high growth rate, and broad substrate spectrum etc. In this study, we attempted to coordinately express multiple hemicellulases in K. marxianus through a 2A-mediated ribosome skipping to self-cleave polyproteins, and investigated their capabilities for saccharification and ethanol production from corncobs. RESULTS Two polycistronic genes IMPX and IMPαX were constructed to test the self-cleavage of P2A sequence from the Foot-and-Mouth Disease virus (FMDV) in K. marxianus. The IMPX gene consisted of a β-mannanase gene M330 (without the stop codon), a P2A sequence and a β-xylanase gene Xyn-CDBFV in turn. In the IMPαX gene, there was an additional α-factor signal sequence in frame with the N-terminus of Xyn-CDBFV. The extracellular β-mannanase activities of the IMPX and IMPαX strains were 21.34 and 15.50 U/mL, respectively, but the extracellular β-xylanase activity of IMPαX strain was much higher than that of the IMPX strain, which was 136.17 and 42.07 U/mL, respectively. Subsequently, two recombinant strains, the IXPαR and IMPαXPαR, were constructed to coordinately and secretorily express two xylantic enzymes, Xyn-CDBFV and β-D-xylosidase RuXyn1, or three hemicellulolytic enzymes including M330, Xyn-CDBFV and RuXyn1. In fed-batch fermentation, extracellular activities of β-xylanase and β-xylosidase in the IXPαR strain were 1664.2 and 0.90 U/mL. Similarly, the IMPαXPαR strain secreted the three enzymes, β-mannanase, β-xylanase, and β-xylosidase, with the activities of 159.8, 2210.5, and 1.25 U/mL, respectively. Hemicellulolases of both strains enhanced the yields of glucose and xylose from diluted acid pretreated (DAP) corncobs when acted synergistically with commercial cellulases. In hybrid saccharification and fermentation (HSF) of DAP corncobs, hemicellulases of the IMPαXPαR strain increased the ethanol yield by 8.7% at 144 h compared with the control. However, both ethanol and xylose yields were increased by 12.7 and 18.2%, respectively, at 120 h in HSF of aqueous ammonia pretreated (AAP) corncobs with this strain. Our results indicated that coordinate expression of hemicellulolytic enzymes in K. marxianus promoted the saccharification and ethanol production from corncobs. CONCLUSIONS The FMDV P2A sequence showed high efficiency in self-cleavage of polyproteins in K. marxianus and could be used for secretory expression of multiple enzymes in the presence of their signal sequences. The IMPαXPαR strain coexpressed three hemicellulolytic enzymes improved the saccharification and ethanol production from corncobs, and could be used as a promising strain for ethanol production from lignocelluloses.
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Affiliation(s)
- Qing Lan
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
| | - Yitong Duan
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
| | - Pingping Wu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
| | - Xueyin Li
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
| | - Yao Yu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
| | - Bo Shi
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, 12 Zhongguancun South Street, Beijing, 100081, People's Republic of China
| | - Jungang Zhou
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China.
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China.
| | - Hong Lu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China.
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China.
- Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, People's Republic of China.
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Filiatrault-Chastel C, Heiss-Blanquet S, Margeot A, Berrin JG. From fungal secretomes to enzymes cocktails: The path forward to bioeconomy. Biotechnol Adv 2021; 52:107833. [PMID: 34481893 DOI: 10.1016/j.biotechadv.2021.107833] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 12/17/2022]
Abstract
Bioeconomy is seen as a way to mitigate the carbon footprint of human activities by reducing at least part of the fossil resources-based economy. In this new paradigm of sustainable development, the use of enzymes as biocatalysts will play an increasing role to provide services and goods. In industry, most of multicomponent enzyme cocktails are of fungal origin. Filamentous fungi secrete complex enzyme sets called "secretomes" that can be utilized as enzyme cocktails to valorize different types of bioresources. In this review, we highlight recent advances in the study of fungal secretomes using improved computational and experimental secretomics methods, the progress in the understanding of industrially important fungi, and the discovery of new enzymatic mechanisms and interplays to degrade renewable resources rich in polysaccharides (e.g. cellulose). We review current biotechnological applications focusing on the benefits and challenges of fungal secretomes for industrial applications with some examples of commercial cocktails of fungal origin containing carbohydrate-active enzymes (CAZymes) and we discuss future trends.
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Affiliation(s)
- Camille Filiatrault-Chastel
- INRAE, Aix Marseille Univ., Biodiversité et Biotechnologie Fongiques, UMR1163, Marseille, France; IFP Energies nouvelles, 1 et 4 avenue de Bois-Préau, 92852 Rueil-Malmaison, France.
| | - Senta Heiss-Blanquet
- IFP Energies nouvelles, 1 et 4 avenue de Bois-Préau, 92852 Rueil-Malmaison, France.
| | - Antoine Margeot
- IFP Energies nouvelles, 1 et 4 avenue de Bois-Préau, 92852 Rueil-Malmaison, France.
| | - Jean-Guy Berrin
- INRAE, Aix Marseille Univ., Biodiversité et Biotechnologie Fongiques, UMR1163, Marseille, France.
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8
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Biorefinery Gets Hot: Thermophilic Enzymes and Microorganisms for Second-Generation Bioethanol Production. Processes (Basel) 2021. [DOI: 10.3390/pr9091583] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
To mitigate the current global energy and the environmental crisis, biofuels such as bioethanol have progressively gained attention from both scientific and industrial perspectives. However, at present, commercialized bioethanol is mainly derived from edible crops, thus raising serious concerns given its competition with feed production. For this reason, lignocellulosic biomasses (LCBs) have been recognized as important alternatives for bioethanol production. Because LCBs supply is sustainable, abundant, widespread, and cheap, LCBs-derived bioethanol currently represents one of the most viable solutions to meet the global demand for liquid fuel. However, the cost-effective conversion of LCBs into ethanol remains a challenge and its implementation has been hampered by several bottlenecks that must still be tackled. Among other factors related to the challenging and variable nature of LCBs, we highlight: (i) energy-demanding pretreatments, (ii) expensive hydrolytic enzyme blends, and (iii) the need for microorganisms that can ferment mixed sugars. In this regard, thermophiles represent valuable tools to overcome some of these limitations. Thus, the aim of this review is to provide an overview of the state-of-the-art technologies involved, such as the use of thermophilic enzymes and microorganisms in industrial-relevant conditions, and to propose possible means to implement thermophiles into second-generation ethanol biorefineries that are already in operation.
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Phytase and carbohydrase inclusion strategies to explore synergy within low-energy diets to optimize 56-day male broiler performance and processing. J APPL POULTRY RES 2020. [DOI: 10.1016/j.japr.2020.09.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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10
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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: 64] [Impact Index Per Article: 16.0] [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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Jain L, Kurmi AK, Kumar A, Narani A, Bhaskar T, Agrawal D. Exploring the flexibility of cellulase cocktail obtained from mutant UV-8 of Talaromyces verruculosus IIPC 324 in depolymerising multiple agro-industrial lignocellulosic feedstocks. Int J Biol Macromol 2020; 154:538-544. [PMID: 32194122 DOI: 10.1016/j.ijbiomac.2020.03.133] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/27/2020] [Accepted: 03/14/2020] [Indexed: 11/17/2022]
Abstract
Effective management and the valorization of agro-industrial lignocellulosic feedstocks can only be realized if a versatile cellulase cocktail is developed that can release glucose at affordable cost irrespective of biomass type. In the present study the flexibility of using cellulase cocktail obtained from mutant UV-8 of Talaromyces verruculosus IIPC 324 in depolymerizing multiple agro-industrial lignocellulosic feedstocks was explored. Five different dilute acid pretreated biomasses were evaluated and cellulase loading was done at 25 mg protein/g cellulose content. After 72 h of hydrolysis at 55 °C and pH 4.5, corn cob and rice straw emerged as the easiest and toughest substrates with saccharification yield of 83.9 ± 1.17 and 35.5 ± 1.16% respectively from their cellulose fraction. Addition of PEG 6000 could retain >65% of all mono-component enzymes present in cellulase cocktail. Structural elucidation of biomasses gave an insight about key features responsible for variable recalcitrance in the different agro-industrial feedstock. Cellulose hydrolysis showed a significant negative correlation in the order of Cr I > S/G ratio > ash content. The chemical composition of lignin had a major impact on enzyme-lignin interactions. Higher H lignin content and lower S/G ratio promoted enzyme desorption, thereby increasing the likelihood of their recycling and reuse.
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Affiliation(s)
- Lavika Jain
- Materials Resource Efficiency Division, CSIR- Indian Institute of Petroleum, Mohkampur, Dehradun 248005, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-HRDC Campus, Ghaziabad 201002, India
| | - Akhilesh Kumar Kurmi
- Materials Resource Efficiency Division, CSIR- Indian Institute of Petroleum, Mohkampur, Dehradun 248005, India
| | - Avnish Kumar
- Materials Resource Efficiency Division, CSIR- Indian Institute of Petroleum, Mohkampur, Dehradun 248005, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-HRDC Campus, Ghaziabad 201002, India
| | - Anand Narani
- Materials Resource Efficiency Division, CSIR- Indian Institute of Petroleum, Mohkampur, Dehradun 248005, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-HRDC Campus, Ghaziabad 201002, India
| | - Thallada Bhaskar
- Materials Resource Efficiency Division, CSIR- Indian Institute of Petroleum, Mohkampur, Dehradun 248005, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-HRDC Campus, Ghaziabad 201002, India
| | - Deepti Agrawal
- Materials Resource Efficiency Division, CSIR- Indian Institute of Petroleum, Mohkampur, Dehradun 248005, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-HRDC Campus, Ghaziabad 201002, India.
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12
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Zhang R. Functional characterization of cellulose-degrading AA9 lytic polysaccharide monooxygenases and their potential exploitation. Appl Microbiol Biotechnol 2020; 104:3229-3243. [PMID: 32076777 DOI: 10.1007/s00253-020-10467-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Revised: 12/25/2019] [Accepted: 02/12/2020] [Indexed: 01/05/2023]
Abstract
Cellulose-degrading auxiliary activity family 9 (AA9) lytic polysaccharide monooxygenases (LPMOs) are known to be widely distributed among filamentous fungi and participate in the degradation of lignocellulose via the oxidative cleavage of celluloses, cello-oligosaccharides, or hemicelluloses. AA9 LPMOs have been reported to have extensive interactions with not only cellulases but also oxidases. The addition of AA9 LPMOs can greatly reduce the amount of cellulase needed for saccharification and increase the yield of glucose. The discovery of AA9 LPMOs has greatly changed our understanding of how fungi degrade cellulose. In this review, apart from summarizing the recent discoveries related to their catalytic reaction, functional diversity, and practical applications, the stability, expression system, and protein engineering of AA9 LPMOs are reviewed for the first time. This review may provide a reference value to further broaden the substrate range of AA9 LPMOs, expand the scope of their practical applications, and realize their customization for industrial utilization.Key Points• The stability and expression system of AA9 LPMOs are reviewed for the first time.• The protein engineering of AA9 LPMOs is systematically summarized for the first time.• The latest research results on the catalytic mechanism of AA9 LPMOs are summarized.• The application of AA9 LPMOs and their relationship with other enzymes are reviewed.
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Affiliation(s)
- Ruiqin Zhang
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China.
- Department of Bioengineering, Huainan Normal University, No. 278 Xueyuannan Road, Huainan, 232038, China.
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13
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Ávila PF, Franco Cairo JPL, Damasio A, Forte MB, Goldbeck R. Xylooligosaccharides production from a sugarcane biomass mixture: Effects of commercial enzyme combinations on bagasse/straw hydrolysis pretreated using different strategies. Food Res Int 2020; 128:108702. [DOI: 10.1016/j.foodres.2019.108702] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 09/19/2019] [Accepted: 09/21/2019] [Indexed: 11/29/2022]
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14
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Zhu L, Xu A, Zhang H, Lu Y, Liu S, Chen X, Chen H. Lignin Reactions and Structural Alternations under Typical Biomass Pretreatment Methods. CURR ORG CHEM 2019. [DOI: 10.2174/1385272823666190806100747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The utilization of biomass in the production of renewable bioenergy and biomaterials has been a popular topic since the past decades as they are rich in carbohydrates. Most biomasses, such as wood, monocotyledons, and agriculture residues, need to be pretreated before the conversion of carbohydrates in order to break down the recalcitrant cell wall structure and increase the fiber accessibility. To date, a variety of pretreatment methods have been developed that vary from physical to chemical and biological methods. Pretreatment processes affect the cell wall physical structure as well as the chemical structure of the cell wall constituents. Comparing to the studies of the cellulose and hemicelluloses structural changes during pretreatment, such studies on lignin are relatively limited. On the other hand, in order to utilize the part of lignin from biorefinery processes, the understanding of the lignin structural changes during the refining process becomes important. In this study, typical pretreatment methods such as hydrothermal pretreatment, alkaline pretreatment, biodegradation, and oxidative pretreatment are introduced and their corresponding impacts on the lignin structures are reviewed.
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Affiliation(s)
- Linjiang Zhu
- Fermentation Technology Institute, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Anjie Xu
- Fermentation Technology Institute, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Hui Zhang
- Fermentation Technology Institute, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Yuele Lu
- Fermentation Technology Institute, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Shijie Liu
- Department of Paper and Bioprocess Engineering, SUNY-College of Environmental Science and Forestry, Syracuse, NY, 13210, United States
| | - Xiaolong Chen
- Fermentation Technology Institute, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Hanchi Chen
- Fermentation Technology Institute, Zhejiang University of Technology, Hangzhou, 310014, China
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15
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Mohapatra S, Mishra SS, Bhalla P, Thatoi H. Engineering grass biomass for sustainable and enhanced bioethanol production. PLANTA 2019; 250:395-412. [PMID: 31236698 DOI: 10.1007/s00425-019-03218-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Accepted: 06/18/2019] [Indexed: 06/09/2023]
Abstract
Bioethanol from lignocellulosic biomass is a promising step for the future energy requirements. Grass is a potential lignocellulosic biomass which can be utilised for biorefinery-based bioethanol production. Grass biomass is a suitable feedstock for bioethanol production due to its all the year around production, requirement of less fertile land and noninterference with food system. However, the processes involved, i.e. pretreatment, enzymatic hydrolysis and fermentation for bioethanol production from grass biomass, are both time consuming and costly. Developing the grass biomass in planta for enhanced bioethanol production is a promising step for maximum utilisation of this valuable feedstock and, thus, is the focus of the present review. Modern breeding techniques and transgenic processes are attractive methods which can be utilised for development of the feedstock. However, the outcomes are not always predictable and the time period required for obtaining a robust variety is generation dependent. Sophisticated genome editing technologies such as synthetic genetic circuits (SGC) or clustered regularly interspaced short palindromic repeats (CRISPR) systems are advantageous for induction of desired traits/heritable mutations in a foreseeable genome location in the 1st mutant generation. Although, its application in grass biomass for bioethanol is limited, these sophisticated techniques are anticipated to exhibit more flexibility in engineering the expression pattern for qualitative and qualitative traits. Nevertheless, the fundamentals rendered by the genetics of the transgenic crops will remain the basis of such developments for obtaining biorefinery-based bioethanol concepts from grass biomass. Grasses which are abundant and widespread in nature epitomise attractive lignocellulosic feedstocks for bioethanol production. The complexity offered by the grass cell wall in terms of lignin recalcitrance and its binding to polysaccharides forms a barricade for its commercialization as a biofuel feedstock. Inspired by the possibilities for rewiring the genetic makeup of grass biomass for reduced lignin and lignin-polysaccharide linkages along with increase in carbohydrates, innovative approaches for in planta modifications are forging ahead. In this review, we highlight the progress made in the field of transgenic grasses for bioethanol production and focus our understanding on improvements of simple breeding techniques and post-harvest techniques for development in shortening of lignin-carbohydrate and carbohydrate-carbohydrate linkages. Further, we discuss about the designer lignins which are aimed for qualitable lignins and also emphasise on remodelling of polysaccharides and mixed-linkage glucans for enhancing carbohydrate content and in planta saccharification efficiency. As a final point, we discuss the role of synthetic genetic circuits and CRISPR systems in targeted improvement of cell wall components without compromising the plant growth and health. It is anticipated that this review can provide a rational approach towards a better understanding of application of in planta genetic engineering aspects for designing synthetic genetic circuits which can promote grass feedstocks for biorefinery-based bioethanol concepts.
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Affiliation(s)
- Sonali Mohapatra
- Department of Biotechnology, College of Engineering and Technology, Biju Patnaik University of Technology, Bhubaneswar, 751003, India.
| | - Suruchee Samparana Mishra
- Department of Biotechnology, College of Engineering and Technology, Biju Patnaik University of Technology, Bhubaneswar, 751003, India
| | - Prerna Bhalla
- Bhupat and Jyoti Mehta School of Biosciences Building, Indian Institute of Technology Madras, Chennai, India
| | - Hrudayanath Thatoi
- Department of Biotechnology, North Orissa University, Sriram Chandra Vihar, Takatpur, Baripada, 757003, Odisha, India
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16
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Tang S, Liu W, Huang C, Lai C, Fan Y, Yong Q. Improving the enzymatic hydrolysis of larch by coupling water pre-extraction with alkaline hydrogen peroxide post-treatment and adding enzyme cocktail. BIORESOURCE TECHNOLOGY 2019; 285:121322. [PMID: 30965281 DOI: 10.1016/j.biortech.2019.121322] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/02/2019] [Accepted: 04/03/2019] [Indexed: 06/09/2023]
Abstract
Soluble arabinogalactan (AG) in larch leads to reagent waste during its biorefining using oxidative pretreatment strategies. A two-stage pretreatment of water pre-extraction followed by alkaline hydrogen peroxide (AHP) pretreatment was investigated to more efficiently convert larch cellulose into glucose, while also obtaining a value-added AG product stream. The results showed that water pre-extraction increases the lignin selectivity of both NaOH and H2O2 reagents, translating to improved lignin removal and enzymatic hydrolysis yields. This was found to be related to cellulose accessibility alongside the effective consumption of the reagents. Moreover, the addition of mannanase also significantly enhanced enzymatic digestibility of pretreated solid from 81.0% to 97.7% (4% H2O2 charge and 180 °C) when 40 U/g mannanase was supplemented with 20 FPU/g cellulase. In all, it was demonstrated that coupling mannanase with cellulase could improve larch's enzymatic digestibility and overall viability for biorefining processes.
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Affiliation(s)
- Shuo Tang
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China
| | - Wanying Liu
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China
| | - Caoxing Huang
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China
| | - Chenhuan Lai
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China
| | - Yimin Fan
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China
| | - Qiang Yong
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China.
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17
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Hydrolysis of plant biomass at different growth stages using enzyme cocktails for increased fermentable hydrolysates. SCIENTIFIC AFRICAN 2019. [DOI: 10.1016/j.sciaf.2019.e00077] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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18
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Badhan A, Huang J, Wang Y, Abbott DW, Di Falco M, Tsang A, McAllister T. Saccharification efficiencies of multi-enzyme complexes produced by aerobic fungi. N Biotechnol 2018; 46:1-6. [PMID: 29803771 DOI: 10.1016/j.nbt.2018.05.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 05/08/2018] [Accepted: 05/09/2018] [Indexed: 11/16/2022]
Abstract
In the present study, we have characterized high molecular weight multi-enzyme complexes in two commercial enzymes produced by Trichoderma reesei (Spezyme CP) and Penicillium funiculosum (Accellerase XC). We successfully identified 146-1000 kDa complexes using Blue native polyacrylamide gel electrophoresis (BN-PAGE) to fractionate the protein profile in both preparations. Identified complexes dissociated into lower molecular weight constituents when loaded on SDS PAGE. Unfolding of the secondary structure of multi-enzyme complexes with trimethylamine (pH >10) suggested that they were not a result of unspecific protein aggregation. Cellulase (CMCase) profiles of extracts of BN-PAGE fractionated protein bands confirmed cellulase activity within the multi-enzyme complexes. A microassay was used to identify protein bands that promoted high levels of glucose release from barley straw. Those with high saccharification yield were subjected to LC-MS analysis to identify the principal enzymatic activities responsible. The results suggest that secretion of proteins by aerobic fungi leads to the formation of high molecular weight multi-enzyme complexes that display activity against carboxymethyl cellulose and barley straw.
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Affiliation(s)
- Ajay Badhan
- Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta, Canada
| | - Jiangli Huang
- Institute of Biological Resources, Jiangxi Academy of Sciences, Nanchang, 330096, China
| | - Yuxi Wang
- Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta, Canada
| | - D Wade Abbott
- Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta, Canada
| | - Marcos Di Falco
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Quebec, H4B 1R6, Canada
| | - Adrian Tsang
- Institute of Biological Resources, Jiangxi Academy of Sciences, Nanchang, 330096, China
| | - Tim McAllister
- Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta, Canada.
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19
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Li J, Lu M, Guo X, Zhang H, Li Y, Han L. Insights into the improvement of alkaline hydrogen peroxide (AHP) pretreatment on the enzymatic hydrolysis of corn stover: Chemical and microstructural analyses. BIORESOURCE TECHNOLOGY 2018; 265:1-7. [PMID: 29860078 DOI: 10.1016/j.biortech.2018.05.082] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 05/21/2018] [Accepted: 05/22/2018] [Indexed: 06/08/2023]
Abstract
The alkaline hydrogen peroxide (AHP) pretreatment (0.5 g H2O2/g corn stover, 30 °C, 24 h) removed 91.53% of the initial lignin and 55.77% of the initial hemicellulose in corn stover and afforded a considerable glucose yield (88.34%) through enzymatic hydrolysis. A combination of chemical and microstructural analyses was used to illustrate the mechanism of the effect of AHP pretreatment on enzymatic hydrolysis. During pretreatment, H2O2-derived radicals effectively spread into and destroyed the cell wall of various parts (vascular bundle sheath, xylem vessels, tracheid, phloem, and parenchyma) of corn stover to remove most of the lignin, acetyl group, and partial hemicellulose. They destroyed the compact structure of the cellulose-hemicellulose-lignin network, increased the cellulase-accessible pore volume by 6 times, doubled the area of exposed cellulose, and decreased the unproductive adsorption of enzymes onto lignin. Combining all the effects, AHP pretreatment effectively improved the cellulose accessibility to enhance the subsequent enzymatic hydrolysis efficiency.
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Affiliation(s)
- Junbao Li
- College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Hai-Dian District, Beijing 100083, PR China
| | - Minsheng Lu
- College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Hai-Dian District, Beijing 100083, PR China
| | - Xiaomiao Guo
- College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Hai-Dian District, Beijing 100083, PR China
| | - Haiyan Zhang
- College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Hai-Dian District, Beijing 100083, PR China
| | - Yaping Li
- College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Hai-Dian District, Beijing 100083, PR China
| | - Lujia Han
- College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Hai-Dian District, Beijing 100083, PR China.
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20
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Conway JM, Crosby JR, McKinley BS, Seals NL, Adams MWW, Kelly RM. Parsing in vivo and in vitro contributions to microcrystalline cellulose hydrolysis by multidomain glycoside hydrolases in theCaldicellulosiruptor besciisecretome. Biotechnol Bioeng 2018; 115:2426-2440. [DOI: 10.1002/bit.26773] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 05/21/2018] [Accepted: 06/21/2018] [Indexed: 01/08/2023]
Affiliation(s)
- Jonathan M. Conway
- Department of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleigh NC
| | - James R. Crosby
- Department of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleigh NC
| | - Bennett S. McKinley
- Department of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleigh NC
| | - Nathaniel L. Seals
- Department of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleigh NC
| | - Michael W. W. Adams
- Department of Biochemistry and Molecular BiologyUniversity of GeorgiaAthens GA
| | - Robert M. Kelly
- Department of Chemical and Biomolecular EngineeringNorth Carolina State UniversityRaleigh NC
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21
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Badhan A, Ribeiro GO, Jones DR, Wang Y, Abbott DW, Di Falco M, Tsang A, McAllister TA. Identification of novel enzymes to enhance the ruminal digestion of barley straw. BIORESOURCE TECHNOLOGY 2018; 260:76-84. [PMID: 29621684 DOI: 10.1016/j.biortech.2018.03.086] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 03/15/2018] [Accepted: 03/17/2018] [Indexed: 06/08/2023]
Abstract
Crude enzyme extracts typically contain a broad spectrum of enzyme activities, most of which are redundant to those naturally produced by the rumen microbiome. Identification of enzyme activities that are synergistic to those produced by the rumen microbiome could enable formulation of enzyme cocktails that improve fiber digestion in ruminants. Compared to untreated barley straw, Viscozyme® increased gas production, dry matter digestion (P < 0.01) and volatile fatty acid production (P < 0.001) in ruminal batch cultures. Fractionation of Viscozyme® by Blue Native PAGE and analyses using a microassay and mass-spectrometry revealed a GH74 endoglucanase, GH71 α-1,3-glucanase, GH5 mannanase, GH7 cellobiohydrolase, GH28 pectinase, and esterases from Viscozyme® contributed to enhanced saccharification of barley straw by rumen mix enzymes. Grouping of these identified activities with their carbohydrate active enzymes (CAZy) counterparts enabled selection of similar CAZymes for downstream production and screening. Mining of these specific activities from other biological systems could lead to high value enzyme formulations for ruminants.
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Affiliation(s)
- Ajay Badhan
- Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta T1J 4P4, Canada
| | - Gabriel O Ribeiro
- Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta T1J 4P4, Canada
| | - Darryl R Jones
- Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta T1J 4P4, Canada
| | - Yuxi Wang
- Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta T1J 4P4, Canada
| | - D Wade Abbott
- Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta T1J 4P4, Canada
| | - Marcos Di Falco
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Adrian Tsang
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Tim A McAllister
- Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta T1J 4P4, Canada.
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22
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Meier KK, Jones SM, Kaper T, Hansson H, Koetsier MJ, Karkehabadi S, Solomon EI, Sandgren M, Kelemen B. Oxygen Activation by Cu LPMOs in Recalcitrant Carbohydrate Polysaccharide Conversion to Monomer Sugars. Chem Rev 2018; 118:2593-2635. [PMID: 29155571 PMCID: PMC5982588 DOI: 10.1021/acs.chemrev.7b00421] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Natural carbohydrate polymers such as starch, cellulose, and chitin provide renewable alternatives to fossil fuels as a source for fuels and materials. As such, there is considerable interest in their conversion for industrial purposes, which is evidenced by the established and emerging markets for products derived from these natural polymers. In many cases, this is achieved via industrial processes that use enzymes to break down carbohydrates to monomer sugars. One of the major challenges facing large-scale industrial applications utilizing natural carbohydrate polymers is rooted in the fact that naturally occurring forms of starch, cellulose, and chitin can have tightly packed organizations of polymer chains with low hydration levels, giving rise to crystalline structures that are highly recalcitrant to enzymatic degradation. The topic of this review is oxidative cleavage of carbohydrate polymers by lytic polysaccharide mono-oxygenases (LPMOs). LPMOs are copper-dependent enzymes (EC 1.14.99.53-56) that, with glycoside hydrolases, participate in the degradation of recalcitrant carbohydrate polymers. Their activity and structural underpinnings provide insights into biological mechanisms of polysaccharide degradation.
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Affiliation(s)
- Katlyn K. Meier
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Stephen M. Jones
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Thijs Kaper
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, California 94304, United States
| | - Henrik Hansson
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Martijn J. Koetsier
- DuPont Industrial Biosciences, Netherlands, Nieuwe Kanaal 7-S, 6709 PA Wageningen, The Netherlands
| | - Saeid Karkehabadi
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Edward I. Solomon
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Mats Sandgren
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Bradley Kelemen
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, California 94304, United States
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Horta MAC, Filho JAF, Murad NF, de Oliveira Santos E, Dos Santos CA, Mendes JS, Brandão MM, Azzoni SF, de Souza AP. Network of proteins, enzymes and genes linked to biomass degradation shared by Trichoderma species. Sci Rep 2018; 8:1341. [PMID: 29358662 PMCID: PMC5778038 DOI: 10.1038/s41598-018-19671-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 01/05/2018] [Indexed: 12/16/2022] Open
Abstract
Understanding relationships between genes responsible for enzymatic hydrolysis of cellulose and synergistic reactions is fundamental for improving biomass biodegradation technologies. To reveal synergistic reactions, the transcriptome, exoproteome, and enzymatic activities of extracts from Trichoderma harzianum, Trichoderma reesei and Trichoderma atroviride under biodegradation conditions were examined. This work revealed co-regulatory networks across carbohydrate-active enzyme (CAZy) genes and secreted proteins in extracts. A set of 80 proteins and respective genes that might correspond to a common system for biodegradation from the studied species were evaluated to elucidate new co-regulated genes. Differences such as one unique base pair between fungal genomes might influence enzyme-substrate binding sites and alter fungal gene expression responses, explaining the enzymatic activities specific to each species observed in the corresponding extracts. These differences are also responsible for the different architectures observed in the co-expression networks.
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Affiliation(s)
| | - Jaire Alves Ferreira Filho
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - Natália Faraj Murad
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, SP, Brazil
| | | | - Clelton Aparecido Dos Santos
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - Juliano Sales Mendes
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - Marcelo Mendes Brandão
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - Sindelia Freitas Azzoni
- Bioethanol Science and Technology Laboratory (CTBE), Brazilian Center of Research in Energy and Materials (CNPEM), Campinas, SP, Brazil
| | - Anete Pereira de Souza
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, SP, Brazil. .,Department of Plant Biology, Biology Institute, University of Campinas (UNICAMP), Campinas, SP, Brazil.
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24
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Song B, Li B, Wang X, Shen W, Park S, Collings C, Feng A, Smith SJ, Walton JD, Ding SY. Real-time imaging reveals that lytic polysaccharide monooxygenase promotes cellulase activity by increasing cellulose accessibility. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:41. [PMID: 29467819 PMCID: PMC5815216 DOI: 10.1186/s13068-018-1023-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 01/11/2018] [Indexed: 05/08/2023]
Abstract
BACKGROUND The high cost of enzymes is one of the key technical barriers that must be overcome to realize the economical production of biofuels and biomaterials from biomass. Supplementation of enzyme cocktails with lytic polysaccharide monooxygenase (LPMO) can increase the efficiency of these cellulase mixtures for biomass conversion. The previous studies have revealed that LPMOs cleave polysaccharide chains by oxidization of the C1 and/or C4 carbons of the monomeric units. However, how LPMOs enhance enzymatic degradation of lignocellulose is still poorly understood. RESULTS In this study, we combined enzymatic assays and real-time imaging using atomic force microscopy (AFM) to study the molecular interactions of an LPMO [TrAA9A, formerly known as TrCel61A) from Trichoderma reesei] and a cellobiohydrolase I (TlCel7A from T. longibrachiatum) with bacterial microcrystalline cellulose (BMCC) as a substrate. Cellulose conversion by TlCel7A alone was enhanced from 46 to 54% by the addition of TrAA9A. Conversion by a mixture of TlCel7A, endoglucanase, and β-glucosidase was increased from 79 to 87% using pretreated BMCC with TrAA9A for 72 h. AFM imaging demonstrated that individual TrAA9A molecules exhibited intermittent random movement along, across, and penetrating into the ribbon-like microfibril structure of BMCC, which was concomitant with the release of a small amount of oxidized sugars and the splitting of large cellulose ribbons into fibrils with smaller diameters. The dividing effect of the cellulose microfibril occurred more rapidly when TrAA9A and TlCel7A were added together compared to TrAA9A alone; TlCel7A alone caused no separation. CONCLUSIONS TrAA9A increases the accessible surface area of BMCC by separating large cellulose ribbons, and thereby enhances cellulose hydrolysis yield. By providing the first direct observation of LPMO action on a cellulosic substrate, this study sheds new light on the mechanisms by which LPMO enhances biomass conversion.
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Affiliation(s)
- Bo Song
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| | - Bingyao Li
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824 USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824 USA
| | - Xiaoyan Wang
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| | - Wei Shen
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824 USA
| | - Sungjin Park
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| | - Cynthia Collings
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824 USA
| | - Anran Feng
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| | - Steve J. Smith
- Nanoscience and Nanoengineering Program, South Dakota School of Mines and Technology, Rapid City, SD 57701 USA
| | - Jonathan D. Walton
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824 USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824 USA
| | - Shi-You Ding
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824 USA
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25
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Kumar D, Murthy GS. Development and validation of a stochastic molecular model of cellulose hydrolysis by action of multiple cellulase enzymes. BIORESOUR BIOPROCESS 2017. [DOI: 10.1186/s40643-017-0184-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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26
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Malgas S, Chandra R, Van Dyk JS, Saddler JN, Pletschke BI. Formulation of an optimized synergistic enzyme cocktail, HoloMix, for effective degradation of various pre-treated hardwoods. BIORESOURCE TECHNOLOGY 2017; 245:52-65. [PMID: 28892706 DOI: 10.1016/j.biortech.2017.08.186] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/25/2017] [Accepted: 08/29/2017] [Indexed: 06/07/2023]
Abstract
In this study, two selected hardwoods were subjected to sodium chlorite delignification and steam explosion, and the impact of pre-treatments on synergistic enzymatic saccharification evaluated. A cellulolytic core-set, CelMix, and a xylanolytic core-set, XynMix, optimised for glucose and xylose release, respectively, were used to formulate HoloMix cocktail for optimal saccharification of various pre-treated hardwoods. For delignified biomass, the optimized HoloMix consisted of 75%:25% protein dosage, CelMix: XynMix, while for untreated and steam exploded biomass the HoloMix consisted of 93.75%:6.25% protein dosage. Saccharification by HoloMix (27.5mgprotein/gbiomass) for 24h achieved 70-100% sugar yields. Pre-treatment of the hardwoods (especially those with a higher proportion of lignin) with a laccase, improved saccharification by HoloMix. This study provided insights into enzymatic hydrolysis of various pre-treated hardwood substrates and showed the same lignocellulolytic cocktail comparable to/if not better than commercial enzyme preparations can be used to efficiently hydrolyse different hardwood species.
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Affiliation(s)
- S Malgas
- Enzyme Science Programme (ESP), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown 6140, Eastern Cape, South Africa
| | - R Chandra
- Forest Products Biotechnology Group, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T1Z4, Canada
| | - J S Van Dyk
- Forest Products Biotechnology Group, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T1Z4, Canada
| | - J N Saddler
- Forest Products Biotechnology Group, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T1Z4, Canada
| | - B I Pletschke
- Enzyme Science Programme (ESP), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown 6140, Eastern Cape, South Africa.
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27
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Ye Y, Li X, Cao Y, Du J, Chen S, Zhao J. A β-xylosidase hyper-production Penicillium oxalicum mutant enhanced ethanol production from alkali-pretreated corn stover. BIORESOURCE TECHNOLOGY 2017; 245:734-742. [PMID: 28917109 DOI: 10.1016/j.biortech.2017.08.155] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 08/23/2017] [Accepted: 08/24/2017] [Indexed: 05/09/2023]
Abstract
β-Xylosidase activity is deficient in most cellulase enzymes secreted by filamentous fungi, which limits effective enzymatic hydrolysis of hemicellulose in lignocellulose materials and resulted in accumulation of xylo-oligosaccharides that inhibit the cellulase and xylanase activitives. An endogenous β-xylosidase gene, xyl3A, was overexpressed using two types of promoters in cellulolytic P. oxalicum RE-10. The mutants RXyl, RGXyl-1 and RGXyl-2 displayed higher β-xylosidase production than native strain RE-10 besides higher cellulase and xylanase activities, especially RGXyl-1, showing the highest β-xylosidase activity of 15.05±1.79IU/mL, about 29 folds higher than native strain, more than the highest level reported by literature. Enzymatic hydrolysis results indicated the cellulase RGXyl-1 not only increased glucose and xylose yields and thus resulted in high ethanol yield during the simultaneous saccharification and fermentation, but decreased the total enzyme loading compared to starting RE-10, which indicated a good prospect of industrial application in bioconversion of lignocellulose.
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Affiliation(s)
- Yanxin Ye
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China
| | - Xuezhi Li
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China
| | - Yuan Cao
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China
| | - Jian Du
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China
| | - Shicheng Chen
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China.
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28
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Qian Y, Zhong L, Gao J, Sun N, Wang Y, Sun G, Qu Y, Zhong Y. Production of highly efficient cellulase mixtures by genetically exploiting the potentials of Trichoderma reesei endogenous cellulases for hydrolysis of corncob residues. Microb Cell Fact 2017; 16:207. [PMID: 29162107 PMCID: PMC5696804 DOI: 10.1186/s12934-017-0825-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Accepted: 11/14/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Trichoderma reesei is one of the most important fungi utilized for cellulase production. However, its cellulase system has been proven to be present in suboptimal ratio for deconstruction of lignocellulosic substrates. Although previous enzymatic optimization studies have acquired different types of in vitro synthetic mixtures for efficient lignocellulose hydrolysis, production of in vivo optimized cellulase mixtures by industrial strains remains one of the obstacles to reduce enzyme cost in the biofuels production from lignocellulosic biomass. RESULTS In this study, we used a systematic genetic strategy based on the pyrG marker to overexpress the major cellulase components in a hypercellulolytic T. reesei strain and produce the highly efficient cellulase mixture for saccharification of corncob residues. We found that overexpression of CBH2 exhibited a 32-fold increase in the transcription level and a comparable protein level to CBH1, the most abundant secreted protein in T. reesei, but did not contribute much to the cellulolytic ability. However, when EG2 was overexpressed with a 46-fold increase in the transcription level and a comparable protein level to CBH2, the engineered strain QPE36 showed a 1.5-fold enhancement in the total cellulase activity (up to 5.8 U/mL FPA) and a significant promotion of saccharification efficiency towards differently pretreated corncob residues. To assist the following genetic manipulations, the marker pyrG was successfully excised by homologous recombination based on resistance to 5-FOA. Furthermore, BGL1 was overexpressed in the EG2 overexpression strain QE51 (pyrG-excised) and a 11.6-fold increase in BGL activity was obtained. The EG2-BGL1 double overexpression strain QEB4 displayed a remarkable enhancement of cellulolytic ability on pretreated corncob residues. Especially, a nearly complete cellulose conversion (94.2%) was found for the delignified corncob residues after 48 h enzymatic saccharification. CONCLUSIONS These results demonstrate that genetically exploiting the potentials of T. reesei endogenous cellulases to produce highly efficient cellulase mixtures is a powerful strategy to promote the saccharification efficiency, which will eventually facilitate cost reduction for lignocellulose-based biofuels.
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Affiliation(s)
- Yuanchao Qian
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China
| | - Lixia Zhong
- Shandong Institute for Food and Drug Control, Jinan, 250101, People's Republic of China
| | - Jia Gao
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China
| | - Ningning Sun
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China
| | - Yifan Wang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China
| | - Guoyong Sun
- Anaesthesiology Department of the Second Hospital of Shandong University, Jinan, 250100, People's Republic of China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China.
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29
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Hansson H, Karkehabadi S, Mikkelsen N, Douglas NR, Kim S, Lam A, Kaper T, Kelemen B, Meier KK, Jones SM, Solomon EI, Sandgren M. High-resolution structure of a lytic polysaccharide monooxygenase from Hypocrea jecorina reveals a predicted linker as an integral part of the catalytic domain. J Biol Chem 2017; 292:19099-19109. [PMID: 28900033 DOI: 10.1074/jbc.m117.799767] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 08/29/2017] [Indexed: 12/17/2022] Open
Abstract
For decades, the enzymes of the fungus Hypocrea jecorina have served as a model system for the breakdown of cellulose. Three-dimensional structures for almost all H. jecorina cellulose-degrading enzymes are available, except for HjLPMO9A, belonging to the AA9 family of lytic polysaccharide monooxygenases (LPMOs). These enzymes enhance the hydrolytic activity of cellulases and are essential for cost-efficient conversion of lignocellulosic biomass. Here, using structural and spectroscopic analyses, we found that native HjLPMO9A contains a catalytic domain and a family-1 carbohydrate-binding module (CBM1) connected via a linker sequence. A C terminally truncated variant of HjLPMO9A containing 21 residues of the predicted linker was expressed at levels sufficient for analysis. Here, using structural, spectroscopic, and biochemical analyses, we found that this truncated variant exhibited reduced binding to and activity on cellulose compared with the full-length enzyme. Importantly, a 0.95-Å resolution X-ray structure of truncated HjLPMO9A revealed that the linker forms an integral part of the catalytic domain structure, covering a hydrophobic patch on the catalytic AA9 module. We noted that the oxidized catalytic center contains a Cu(II) coordinated by two His ligands, one of which has a His-brace in which the His-1 terminal amine group also coordinates to a copper. The final equatorial position of the Cu(II) is occupied by a water-derived ligand. The spectroscopic characteristics of the truncated variant were not measurably different from those of full-length HjLPMO9A, indicating that the presence of the CBM1 module increases the affinity of HjLPMO9A for cellulose binding, but does not affect the active site.
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Affiliation(s)
- Henrik Hansson
- From the Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Saeid Karkehabadi
- From the Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Nils Mikkelsen
- From the Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | | | - Steve Kim
- DuPont Industrial Biosciences, Palo Alto, California 94304, and
| | - Anna Lam
- DuPont Industrial Biosciences, Palo Alto, California 94304, and
| | - Thijs Kaper
- DuPont Industrial Biosciences, Palo Alto, California 94304, and
| | - Brad Kelemen
- DuPont Industrial Biosciences, Palo Alto, California 94304, and
| | - Katlyn K Meier
- the Department of Chemistry, Stanford University, Stanford, California 94305
| | - Stephen M Jones
- the Department of Chemistry, Stanford University, Stanford, California 94305
| | - Edward I Solomon
- the Department of Chemistry, Stanford University, Stanford, California 94305
| | - Mats Sandgren
- From the Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden,
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30
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Affiliation(s)
- Yifei Zhang
- Department of Biomedical
Engineering, Columbia University, New York, New York 10027, United States
| | - Henry Hess
- Department of Biomedical
Engineering, Columbia University, New York, New York 10027, United States
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31
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Malgas S, Thoresen M, van Dyk JS, Pletschke BI. Time dependence of enzyme synergism during the degradation of model and natural lignocellulosic substrates. Enzyme Microb Technol 2017; 103:1-11. [DOI: 10.1016/j.enzmictec.2017.04.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 04/18/2017] [Accepted: 04/21/2017] [Indexed: 10/19/2022]
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32
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Kim IJ, Lee HJ, Kim KH. Pure enzyme cocktails tailored for the saccharification of sugarcane bagasse pretreated by using different methods. Process Biochem 2017. [DOI: 10.1016/j.procbio.2017.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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33
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Microplate-Based Evaluation of the Sugar Yield from Giant Reed, Giant Miscanthus and Switchgrass after Mild Chemical Pre-Treatments and Hydrolysis with Tailored Trichoderma Enzymatic Blends. Appl Biochem Biotechnol 2017; 183:876-892. [DOI: 10.1007/s12010-017-2470-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 03/29/2017] [Indexed: 11/26/2022]
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34
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Chylenski P, Forsberg Z, Ståhlberg J, Várnai A, Lersch M, Bengtsson O, Sæbø S, Horn SJ, Eijsink VGH. Development of minimal enzyme cocktails for hydrolysis of sulfite-pulped lignocellulosic biomass. J Biotechnol 2017; 246:16-23. [PMID: 28219736 DOI: 10.1016/j.jbiotec.2017.02.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 01/26/2017] [Accepted: 02/13/2017] [Indexed: 01/02/2023]
Abstract
Despite recent progress, saccharification of lignocellulosic biomass is still a major cost driver in biorefining. In this study, we present the development of minimal enzyme cocktails for hydrolysis of Norway spruce and sugarcane bagasse, which were pretreated using the so-called BALI™ process, which is based on sulfite pulping technology. Minimal enzyme cocktails were composed using several glycoside hydrolases purified from the industrially relevant filamentous fungus Trichoderma reesei and a purified commercial β-glucosidase from Aspergillus niger. The contribution of in-house expressed lytic polysaccharide monooxygenases (LPMOs) was also tested, since oxidative cleavage of cellulose by such LPMOs is known to be beneficial for conversion efficiency. We show that the optimized cocktails permit efficient saccharification at reasonable enzyme loadings and that the effect of the LPMOs is substrate-dependent. Using a cocktail comprising only four enzymes, glucan conversion for Norway spruce reached >80% at enzyme loadings of 8mg/g glucan, whereas almost 100% conversion was achieved at 16mg/g.
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Affiliation(s)
- Piotr Chylenski
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Zarah Forsberg
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Jerry Ståhlberg
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Anikó Várnai
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | | | | | - Solve Sæbø
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Svein Jarle Horn
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Vincent G H Eijsink
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway.
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35
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Functional diversity for biomass deconstruction in family 5 subfamily 5 (GH5_5) of fungal endo-β1,4-glucanases. Appl Microbiol Biotechnol 2017; 101:4093-4101. [PMID: 28197688 DOI: 10.1007/s00253-017-8168-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 01/25/2017] [Accepted: 01/27/2017] [Indexed: 12/21/2022]
Abstract
Endo-β1,4-glucanases in glycosyl hydrolase family 5 (GH5) are ubiquitous enzymes in the multicellular fungi and are common components of enzyme cocktails for biomass conversion. We recently showed that an endo-glucanase of subfamily 5 of GH5 (GH5_5) from Sporotrichum thermophile (StCel5A) was more effective at releasing glucose from pretreated corn stover, when part of an eight-component synthetic enzyme mixture, compared to its closely related counterpart from Trichoderma reesei, TrCel5A. StCel5A and TrCel5A belong to different clades of GH5_5 (GH5_5_1 and GH5_5_2, respectively). To test whether the superior activity of StCel5A was a general property of all enzymes in the GH5_5_2 clade, StCel5A, TrCel5A, and two additional members of each subfamily were expressed in a common host that had been engineered to suppress its native cellulases (T. reesei Δxyr1) and compared against each other alone on pure substrates, in synthetic mixtures on pure substrates, and against each other in synthetic mixtures on real biomass. The results indicated that superiority is a unique property of StCel5A and not of GH5_5_2 generally. The six Cel5A enzymes had significant differences in relative activities on different substrates, in specific activities, and in sensitivities to mannan inhibition. Importantly, the behavior of the six endo-glucanases on pure cellulose substrates did not predict their behavior in combination with other cellulolytic enzymes on a real lignocellulosic biomass substrate.
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36
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Kim IJ, Seo N, An HJ, Kim JH, Harris PV, Kim KH. Type-dependent action modes of TtAA9E and TaAA9A acting on cellulose and differently pretreated lignocellulosic substrates. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:46. [PMID: 28250814 PMCID: PMC5322634 DOI: 10.1186/s13068-017-0721-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 02/02/2017] [Indexed: 05/15/2023]
Abstract
BACKGROUND Lytic polysaccharide monooxygenase (LPMO) is a group of recently identified proteins that catalyze oxidative cleavage of the glycosidic linkages of cellulose and other polysaccharides. By utilizing the oxidative mode of action, LPMOs are able to enhance the efficiency of cellulase in the hydrolysis of cellulose. Particularly, auxiliary activity family 9 (AA9) is a group of fungal LPMOs that show a type-dependent regioselectivity on cellulose in which Types 1, 2, and 3 hydroxylate at C1, C4, and C1 and C4 positions, respectively. In this study, we investigated comparative characteristics of TtAA9E from Thielavia terrestris belonging to Type 1 and TaAA9A from Thermoascus aurantiacus belonging to Type 3 on cellulose and pretreated lignocellulose. RESULTS From product analysis, TtAA9E dominantly generated oligosaccharides with an aldonic acid form, which is an evidence of C1 oxidation, while TaAA9A generated oligosaccharides with both aldonic acid and 4-ketoaldose forms, which is evidence of C1 and C4 oxidations, respectively. For hydrolysis of cellulose (Avicel) by cellulase, higher synergism was observed for TtAA9E than for TaAA9A. For hydrolysis of pretreated lignocellulose using rice straw, synergistic behaviors of TtAA9E and TaAA9A were different depending on the pretreatment of rice straw. Specifically, on acid-pretreated rice straw, TtAA9E showed a higher synergism than TaAA9A while on alkali-pretreated rice straw, TaAA9A showed a higher synergism than TtAA9E. CONCLUSIONS We show type-dependent action modes of TtAA9E and TaAA9A for cellulose oxidation together with substrate-dependent synergistic hydrolysis of cellulosic substrates. The results obtained from this study indicate the different behaviors of AA9s on cellulose and pretreated lignocellulose, suggesting a selection of AA9 proteins specific to substrates is required for industrial utilization.
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Affiliation(s)
- In Jung Kim
- Department of Biotechnology, Korea University, Graduate School, Seoul, 02841 South Korea
| | - Nari Seo
- Graduate School of Analytical Science & Technology and Asia-Pacific Glycomics Reference Site, Chungnam National University, Daejeon, 34134 South Korea
| | - Hyun Joo An
- Graduate School of Analytical Science & Technology and Asia-Pacific Glycomics Reference Site, Chungnam National University, Daejeon, 34134 South Korea
| | - Jae-Han Kim
- Department of Food and Nutrition, Chungnam National University, Daejeon, 34134 South Korea
| | | | - Kyoung Heon Kim
- Department of Biotechnology, Korea University, Graduate School, Seoul, 02841 South Korea
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37
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Goldbeck R, Gonçalves TA, Damásio AR, Brenelli LB, Wolf LD, Paixão DA, Rocha GJ, Squina FM. Effect of hemicellulolytic enzymes to improve sugarcane bagasse saccharification and xylooligosaccharides production. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.molcatb.2016.05.013] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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38
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Comparative Community Proteomics Demonstrates the Unexpected Importance of Actinobacterial Glycoside Hydrolase Family 12 Protein for Crystalline Cellulose Hydrolysis. mBio 2016; 7:mBio.01106-16. [PMID: 27555310 PMCID: PMC4999548 DOI: 10.1128/mbio.01106-16] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Glycoside hydrolases (GHs) are key enzymes in the depolymerization of plant-derived cellulose, a process central to the global carbon cycle and the conversion of plant biomass to fuels and chemicals. A limited number of GH families hydrolyze crystalline cellulose, often by a processive mechanism along the cellulose chain. During cultivation of thermophilic cellulolytic microbial communities, substantial differences were observed in the crystalline cellulose saccharification activities of supernatants recovered from divergent lineages. Comparative community proteomics identified a set of cellulases from a population closely related to actinobacterium Thermobispora bispora that were highly abundant in the most active consortium. Among the cellulases from T. bispora, the abundance of a GH family 12 (GH12) protein correlated most closely with the changes in crystalline cellulose hydrolysis activity. This result was surprising since GH12 proteins have been predominantly characterized as enzymes active on soluble polysaccharide substrates. Heterologous expression and biochemical characterization of the suite of T. bispora hydrolytic cellulases confirmed that the GH12 protein possessed the highest activity on multiple crystalline cellulose substrates and demonstrated that it hydrolyzes cellulose chains by a predominantly random mechanism. This work suggests that the role of GH12 proteins in crystalline cellulose hydrolysis by cellulolytic microbes should be reconsidered. Cellulose is the most abundant organic polymer on earth, and its enzymatic hydrolysis is a key reaction in the global carbon cycle and the conversion of plant biomass to biofuels. The glycoside hydrolases that depolymerize crystalline cellulose have been primarily characterized from isolates. In this study, we demonstrate that adapting microbial consortia from compost to grow on crystalline cellulose generated communities whose soluble enzymes exhibit differential abilities to hydrolyze crystalline cellulose. Comparative proteomics of these communities identified a protein of glycoside hydrolase family 12 (GH12), a family of proteins previously observed to primarily hydrolyze soluble substrates, as a candidate that accounted for some of the differences in hydrolytic activities. Heterologous expression confirmed that the GH12 protein identified by proteomics was active on crystalline cellulose and hydrolyzed cellulose by a random mechanism, in contrast to most cellulases that act on the crystalline polymer in a processive mechanism.
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39
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Bischof RH, Ramoni J, Seiboth B. Cellulases and beyond: the first 70 years of the enzyme producer Trichoderma reesei. Microb Cell Fact 2016; 15:106. [PMID: 27287427 PMCID: PMC4902900 DOI: 10.1186/s12934-016-0507-6] [Citation(s) in RCA: 299] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 06/01/2016] [Indexed: 11/10/2022] Open
Abstract
More than 70 years ago, the filamentous ascomycete Trichoderma reesei was isolated on the Solomon Islands due to its ability to degrade and thrive on cellulose containing fabrics. This trait that relies on its secreted cellulases is nowadays exploited by several industries. Most prominently in biorefineries which use T. reesei enzymes to saccharify lignocellulose from renewable plant biomass in order to produce biobased fuels and chemicals. In this review we summarize important milestones of the development of T. reesei as the leading production host for biorefinery enzymes, and discuss emerging trends in strain engineering. Trichoderma reesei has very recently also been proposed as a consolidated bioprocessing organism capable of direct conversion of biopolymeric substrates to desired products. We therefore cover this topic by reviewing novel approaches in metabolic engineering of T. reesei.
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Affiliation(s)
- Robert H Bischof
- Austrian Centre of Industrial Biotechnology (ACIB) GmbH c/o Institute of Chemical Engineering, TU Wien, Gumpendorferstraße 1a, 1060, Vienna, Austria
| | - Jonas Ramoni
- Molecular Biotechnology, Research Area Biochemical Technology, Institute of Chemical Engineering, TU Wien, Gumpendorferstraße 1a, 1060, Vienna, Austria
| | - Bernhard Seiboth
- Austrian Centre of Industrial Biotechnology (ACIB) GmbH c/o Institute of Chemical Engineering, TU Wien, Gumpendorferstraße 1a, 1060, Vienna, Austria. .,Molecular Biotechnology, Research Area Biochemical Technology, Institute of Chemical Engineering, TU Wien, Gumpendorferstraße 1a, 1060, Vienna, Austria.
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40
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Park SH, Ong RG, Sticklen M. Strategies for the production of cell wall-deconstructing enzymes in lignocellulosic biomass and their utilization for biofuel production. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:1329-44. [PMID: 26627868 PMCID: PMC5063159 DOI: 10.1111/pbi.12505] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 10/23/2015] [Accepted: 11/02/2015] [Indexed: 05/18/2023]
Abstract
Microbial cell wall-deconstructing enzymes are widely used in the food, wine, pulp and paper, textile, and detergent industries and will be heavily utilized by cellulosic biorefineries in the production of fuels and chemicals. Due to their ability to use freely available solar energy, genetically engineered bioenergy crops provide an attractive alternative to microbial bioreactors for the production of cell wall-deconstructing enzymes. This review article summarizes the efforts made within the last decade on the production of cell wall-deconstructing enzymes in planta for use in the deconstruction of lignocellulosic biomass. A number of strategies have been employed to increase enzyme yields and limit negative impacts on plant growth and development including targeting heterologous enzymes into specific subcellular compartments using signal peptides, using tissue-specific or inducible promoters to limit the expression of enzymes to certain portions of the plant or certain times, and fusion of amplification sequences upstream of the coding region to enhance expression. We also summarize methods that have been used to access and maintain activity of plant-generated enzymes when used in conjunction with thermochemical pretreatments for the production of lignocellulosic biofuels.
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Affiliation(s)
- Sang-Hyuck Park
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA
| | - Rebecca Garlock Ong
- Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, Lansing, MI, USA
- Department of Chemical Engineering, Michigan Technological University, Houghton, MI, USA
| | - Mariam Sticklen
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA
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41
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Katsimpouras C, Dimarogona M, Petropoulos P, Christakopoulos P, Topakas E. A thermostable GH26 endo-β-mannanase from Myceliophthora thermophila capable of enhancing lignocellulose degradation. Appl Microbiol Biotechnol 2016; 100:8385-97. [PMID: 27193267 DOI: 10.1007/s00253-016-7609-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 04/24/2016] [Accepted: 05/01/2016] [Indexed: 10/21/2022]
Abstract
The endomannanase gene em26a from the thermophilic fungus Myceliophthora thermophila, belonging to the glycoside hydrolase family 26, was functionally expressed in the methylotrophic yeast Pichia pastoris. The putative endomannanase, dubbed MtMan26A, was purified to homogeneity (60 kDa) and subsequently characterized. The optimum pH and temperature for the enzymatic activity of MtMan26A were 6.0 and 60 °C, respectively. MtMan26A showed high specific activity against konjac glucomannan and carob galactomannan, while it also exhibited high thermal stability with a half-life of 14.4 h at 60 °C. Thermostability is of great importance, especially in industrial processes where harsh conditions are employed. With the aim of better understanding its structure-function relationships, a homology model of MtMan26A was constructed, based on the crystallographic structure of a close homologue. Finally, the addition of MtMan26A as a supplement to the commercial enzyme mixture Celluclast® 1.5 L and Novozyme® 188 resulted in enhanced enzymatic hydrolysis of pretreated beechwood sawdust, improving the release of total reducing sugars and glucose by 13 and 12 %, respectively.
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Affiliation(s)
- Constantinos Katsimpouras
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens, 15780, Greece
| | - Maria Dimarogona
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens, 15780, Greece
| | - Pericles Petropoulos
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens, 15780, Greece
| | - Paul Christakopoulos
- Biochemical and Chemical Process Engineering, Division of Sustainable Process Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187, Luleå, Sweden
| | - Evangelos Topakas
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens, 15780, Greece.
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Lima MS, Damasio ARDL, Crnkovic PM, Pinto MR, da Silva AM, da Silva JCR, Segato F, de Lucas RC, Jorge JA, Polizeli MDLTDM. Co-cultivation of Aspergillus nidulans Recombinant Strains Produces an Enzymatic Cocktail as Alternative to Alkaline Sugarcane Bagasse Pretreatment. Front Microbiol 2016; 7:583. [PMID: 27199917 PMCID: PMC4848300 DOI: 10.3389/fmicb.2016.00583] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 04/11/2016] [Indexed: 11/13/2022] Open
Abstract
Plant materials represent a strategic energy source because they can give rise to sustainable biofuels through the fermentation of their carbohydrates. A clear example of a plant-derived biofuel resource is the sugar cane bagasse exhibiting 60-80% of fermentable sugars in its composition. However, the current methods of plant bioconversion employ severe and harmful chemical/physical pretreatments raising biofuel cost production and environmental degradation. Replacing these methods with co-cultivated enzymatic cocktails is an alternative. Here we propose a pretreatment for sugarcane bagasse using a multi-enzymatic cocktail from the co-cultivation of four Aspergillus nidulans recombinant strains. The co-cultivation resulted in the simultaneous production of GH51 arabinofuranosidase (AbfA), GH11 endo-1,4-xylanase (XlnA), GH43 endo-1,5-arabinanase (AbnA) and GH12 xyloglucan specific endo-β-1,4-glucanase (XegA). This core set of recombinant enzymes was more efficient than the alternative alkaline method in maintaining the cellulose integrity and exposing this cellulose to the following saccharification process. Thermogravimetric and differential thermal analysis revealed residual byproducts on the alkali pretreated biomass, which were not found in the enzymatic pretreatment. Therefore, the enzymatic pretreatment was residue-free and seemed to be more efficient than the applied alkaline method, which makes it suitable for bioethanol production.
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Affiliation(s)
- Matheus S Lima
- Department of Biology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo São Paulo, Brazil
| | - André R de L Damasio
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas São Paulo, Brazil
| | - Paula M Crnkovic
- Department of Mechanical Engineering, University of São Paulo São Paulo, Brazil
| | - Marcelo R Pinto
- Laboratory of Biopathology and Molecular Biology, Uberaba University Uberaba, Brazil
| | | | - Jean C R da Silva
- Federal Institute of Education, Science and Technology of São Paulo São Paulo, Brazil
| | - Fernando Segato
- Department of Biotechnology, Engineering School of Lorena, University of São Paulo São Paulo, Brazil
| | - Rosymar C de Lucas
- Department of Biology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São PauloSão Paulo, Brazil; Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São PauloSão Paulo, Brazil
| | - João A Jorge
- Department of Biology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo São Paulo, Brazil
| | - Maria de L T de M Polizeli
- Department of Biology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo São Paulo, Brazil
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Aguilar-Pontes MV, Zhou M, van der Horst S, Theelen B, de Vries RP, van den Brink J. Sexual crossing of thermophilic fungus Myceliophthora heterothallica improved enzymatic degradation of sugar beet pulp. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:41. [PMID: 26900400 PMCID: PMC4761134 DOI: 10.1186/s13068-016-0460-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/10/2016] [Indexed: 05/21/2023]
Abstract
BACKGROUND Enzymatic degradation of plant biomass requires a complex mixture of many different enzymes. Like most fungi, thermophilic Myceliophthora species therefore have a large set of enzymes targeting different linkages in plant polysaccharides. The majority of these enzymes have not been functionally characterized, and their role in plant biomass degradation is unknown. The biotechnological challenge is to select the right set of enzymes to efficiently degrade a particular biomass. This study describes a strategy using sexual crossing and screening with the thermophilic fungus Myceliophthora heterothallica to identify specific enzymes associated with improved sugar beet pulp saccharification. RESULTS Two genetically diverse M. heterothallica strains CBS 203.75 and CBS 663.74 were used to generate progenies with improved growth on sugar beet pulp. One progeny, named SBP.F1.2.11, had a different genetic pattern from the parental strains and had improved saccharification activity after the growth on 3 % sugar beet pulp. The improved SBP saccharification was not explained by altered activities of the major (hemi-)cellulases. Exo-proteome analysis of progeny and parental strains after 7-day growth on sugar beet pulp showed that only 17 of the 133 secreted CAZy enzymes were more abundant in progeny SBP.F1.2.11. Particularly one enzyme belonging to the carbohydrate esterase family 5 (CE5) was more abundant in SBP.F1.2.11. This CE5-CBM1 enzyme, named as Axe1, was phylogenetically related to acetyl xylan esterases. Biochemical characterization of Axe1 confirmed de-acetylation activity with optimal activities at 75-85 °C and pH 5.5-6.0. Supplementing Axe1 to CBS 203.75 enzyme set improved release of xylose and glucose from sugar beet pulp. CONCLUSIONS This study identified beneficial enzymes for sugar beet pulp saccharification by selecting progeny with improved growth on this particular substrate. Saccharification of sugar beet pulp was improved by supplementing enzyme mixtures with a previously uncharacterized CE5-CBM1 acetyl xylan esterase. This shows that sexual crossing and selection of M. heterothallica are the successful strategy to improve the composition of enzyme mixtures for efficient plant biomass degradation.
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Affiliation(s)
- Maria Victoria Aguilar-Pontes
- />Fungal Physiology, CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands
- />Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Miaomiao Zhou
- />Fungal Physiology, CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands
- />Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Sjors van der Horst
- />Fungal Physiology, CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands
- />Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Bart Theelen
- />Yeast and Basidiomycete Research, CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands
| | - Ronald P. de Vries
- />Fungal Physiology, CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands
- />Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Joost van den Brink
- />Fungal Physiology, CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands
- />Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
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Karnaouri A, Matsakas L, Topakas E, Rova U, Christakopoulos P. Development of Thermophilic Tailor-Made Enzyme Mixtures for the Bioconversion of Agricultural and Forest Residues. Front Microbiol 2016; 7:177. [PMID: 26909078 PMCID: PMC4754399 DOI: 10.3389/fmicb.2016.00177] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/01/2016] [Indexed: 11/13/2022] Open
Abstract
Even though the main components of all lignocellulosic feedstocks include cellulose, hemicellulose, as well as the protective lignin matrix, there are some differences in structure, such as in hardwoods and softwoods, which may influence the degradability of the materials. Under this view, various types of biomass might require a minimal set of enzymes that has to be tailor-made. Partially defined complex mixtures that are currently commercially used are not adapted to efficiently degrade different materials, so novel enzyme mixtures have to be customized. Development of these cocktails requires better knowledge about the specific activities involved, in order to optimize hydrolysis. The role of filamentous fungus Myceliophthora thermophila and its complete enzymatic repertoire for the bioconversion of complex carbohydrates has been widely proven. In this study, four core cellulases (MtCBH7, MtCBH6, MtEG5, and MtEG7), in the presence of other four "accessory" enzymes (mannanase, lytic polyssacharide monooxygenase MtGH61, xylanase, MtFae1a) and β-glucosidase MtBGL3, were tested as a nine-component cocktail against one model substrate (phosphoric acid swollen cellulose) and four hydrothermally pretreated natural substrates (wheat straw as an agricultural waste, birch, and spruce biomass, as forest residues). Synergistic interactions among different enzymes were determined using a suitable design of experiments methodology. The results suggest that for the hydrolysis of the pure substrate (PASC), high proportions of MtEG7 are needed for efficient yields. MtCBH7 and MtEG7 are enzymes of major importance during the hydrolysis of pretreated wheat straw, while MtCBH7 plays a crucial role in case of spruce. Cellobiohydrolases MtCBH6 and MtCBH7 act in combination and are key enzymes for the hydrolysis of the hardwood (birch). Optimum combinations were predicted from suitable statistical models which were able to further increase hydrolysis yields, suggesting that tailor-made enzyme mixtures targeted toward a particular residual biomass can help maximize hydrolysis yields. The present work demonstrates the change from "one cocktail for all" to "tailor-made cocktails" that are needed for the efficient saccharification of targeted feed stocks prior to the production of biobased products through the biorefinery concept.
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Affiliation(s)
- Anthi Karnaouri
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Leonidas Matsakas
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Evangelos Topakas
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of TechnologyLuleå, Sweden; Biotechnology Laboratory, Department of Synthesis and Development of Industrial Processes, School of Chemical Engineering, National Technical University of AthensAthens, Greece
| | - Ulrika Rova
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
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Classification, mode of action and production strategy of xylanase and its application for biofuel production from water hyacinth. Int J Biol Macromol 2016; 82:1041-54. [DOI: 10.1016/j.ijbiomac.2015.10.086] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 10/26/2015] [Accepted: 10/27/2015] [Indexed: 01/07/2023]
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Chatzifragkou A, Kosik O, Prabhakumari PC, Lovegrove A, Frazier RA, Shewry PR, Charalampopoulos D. Biorefinery strategies for upgrading Distillers’ Dried Grains with Solubles (DDGS). Process Biochem 2015. [DOI: 10.1016/j.procbio.2015.09.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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47
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Xie C, Luo W, Li Z, Yan L, Zhu Z, Wang J, Hu Z, Peng Y. Secretome analysis of Pleurotus eryngii reveals enzymatic composition for ramie stalk degradation. Electrophoresis 2015; 37:310-20. [PMID: 26525014 DOI: 10.1002/elps.201500312] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Revised: 08/27/2015] [Accepted: 10/18/2015] [Indexed: 11/07/2022]
Abstract
Pleurotus eryngii (P. eryngii) can secrete large amount of hydrolytic and oxidative enzymes to degrade lignocellulosic biomass. In spite of several researches on the individual lignolytic enzymes, a direct deconstruction of lignocellulose by enzyme mixture is not yet possible. Identifying more high-performance enzymes or enzyme complexes will lead to efficient in vitro lignocelluloses degradation. In this report, secretomic analysis was used to search for the new or interesting enzymes for lignocellulose degradation. Besides, the utilization ability of P. eryngii to ramie stalk substrate was evaluated from the degradation of cellulose, hemicellulose, and lignin in medium and six extracellular enzymes activities during different growth stages were discussed. The results showed that a high biological efficiency of 71% was obtained; cellulose, hemicelluloses, and lignin decomposition rates of P. eryngii were 29.2, 26.0, and 51.2%, respectively. Enzyme activity showed that carboxymethyl cellulase, xylanase, laccase, and peroxidase activity peaks appeared at the primordial initiation stage. In addition, we profiled a global view of the secretome of P. eryngii cultivated in ramie stalk media to understand the mechanism behind lignocellulosic biomass hydrolysis. Eighty-seven nonredundant proteins were identified and a diverse group of enzymes, including cellulases, hemicellulases, pectinase, ligninase, protease, peptidases, and phosphatase implicated in lignocellulose degradation were found. In conclusion, the information in this report will be helpful to better understand the lignocelluloses degradation mechanisms of P. eryngii.
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Affiliation(s)
- Chunliang Xie
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, P. R. China
| | - Wei Luo
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, P. R. China
| | - Zhimin Li
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, P. R. China
| | - Li Yan
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, P. R. China
| | - Zuohua Zhu
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, P. R. China
| | - Jing Wang
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, P. R. China
| | - Zhenxiu Hu
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, P. R. China
| | - Yuande Peng
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, P. R. China
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48
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Research Progress Concerning Fungal and Bacterial β-Xylosidases. Appl Biochem Biotechnol 2015; 178:766-95. [DOI: 10.1007/s12010-015-1908-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 10/22/2015] [Indexed: 01/08/2023]
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49
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Deng K, Guenther JM, Gao J, Bowen BP, Tran H, Reyes-Ortiz V, Cheng X, Sathitsuksanoh N, Heins R, Takasuka TE, Bergeman LF, Geertz-Hansen H, Deutsch S, Loqué D, Sale KL, Simmons BA, Adams PD, Singh AK, Fox BG, Northen TR. Development of a High Throughput Platform for Screening Glycoside Hydrolases Based on Oxime-NIMS. Front Bioeng Biotechnol 2015; 3:153. [PMID: 26528471 PMCID: PMC4603251 DOI: 10.3389/fbioe.2015.00153] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 09/21/2015] [Indexed: 12/26/2022] Open
Abstract
Cost-effective hydrolysis of biomass into sugars for biofuel production requires high-performance low-cost glycoside hydrolase (GH) cocktails that are active under demanding process conditions. Improving the performance of GH cocktails depends on knowledge of many critical parameters, including individual enzyme stabilities, optimal reaction conditions, kinetics, and specificity of reaction. With this information, rate- and/or yield-limiting reactions can be potentially improved through substitution, synergistic complementation, or protein engineering. Given the wide range of substrates and methods used for GH characterization, it is difficult to compare results across a myriad of approaches to identify high performance and synergistic combinations of enzymes. Here, we describe a platform for systematic screening of GH activities using automatic biomass handling, bioconjugate chemistry, robotic liquid handling, and nanostructure-initiator mass spectrometry (NIMS). Twelve well-characterized substrates spanning the types of glycosidic linkages found in plant cell walls are included in the experimental workflow. To test the application of this platform and substrate panel, we studied the reactivity of three engineered cellulases and their synergy of combination across a range of reaction conditions and enzyme concentrations. We anticipate that large-scale screening using the standardized platform and substrates will generate critical datasets to enable direct comparison of enzyme activities for cocktail design.
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Affiliation(s)
- Kai Deng
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Sandia National Laboratories , Livermore, CA , USA
| | - Joel M Guenther
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Sandia National Laboratories , Livermore, CA , USA
| | - Jian Gao
- Lawrence Berkeley National Laboratory , Berkeley, CA , USA
| | | | - Huu Tran
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Sandia National Laboratories , Livermore, CA , USA
| | - Vimalier Reyes-Ortiz
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Lawrence Berkeley National Laboratory , Berkeley, CA , USA
| | - Xiaoliang Cheng
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Lawrence Berkeley National Laboratory , Berkeley, CA , USA
| | - Noppadon Sathitsuksanoh
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Lawrence Berkeley National Laboratory , Berkeley, CA , USA
| | - Richard Heins
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Sandia National Laboratories , Livermore, CA , USA
| | - Taichi E Takasuka
- US Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin , Madison, WI , USA
| | - Lai F Bergeman
- US Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin , Madison, WI , USA
| | | | - Samuel Deutsch
- Lawrence Berkeley National Laboratory , Berkeley, CA , USA ; Joint Genome Institute , Walnut Creek, CA , USA
| | - Dominique Loqué
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Lawrence Berkeley National Laboratory , Berkeley, CA , USA
| | - Kenneth L Sale
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Sandia National Laboratories , Livermore, CA , USA
| | - Blake A Simmons
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Sandia National Laboratories , Livermore, CA , USA
| | - Paul D Adams
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Lawrence Berkeley National Laboratory , Berkeley, CA , USA ; Department of Bioengineering, University of California Berkeley , Berkeley, CA , USA
| | - Anup K Singh
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Sandia National Laboratories , Livermore, CA , USA
| | - Brian G Fox
- US Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin , Madison, WI , USA ; Department of Biochemistry, University of Wisconsin , Madison, WI , USA
| | - Trent R Northen
- US Department of Energy Joint BioEnergy Institute , Emeryville, CA , USA ; Lawrence Berkeley National Laboratory , Berkeley, CA , USA
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50
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Improvement in Saccharification Yield of Mixed Rumen Enzymes by Identification of Recalcitrant Cell Wall Constituents Using Enzyme Fingerprinting. BIOMED RESEARCH INTERNATIONAL 2015; 2015:562952. [PMID: 26180803 PMCID: PMC4477221 DOI: 10.1155/2015/562952] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 01/15/2015] [Accepted: 01/16/2015] [Indexed: 11/17/2022]
Abstract
Identification of recalcitrant factors that limit digestion of forages and the development of enzymatic approaches that improve hydrolysis could play a key role in improving the efficiency of meat and milk production in ruminants. Enzyme fingerprinting of barley silage fed to heifers and total tract indigestible fibre residue (TIFR) collected from feces was used to identify cell wall components resistant to total tract digestion. Enzyme fingerprinting results identified acetyl xylan esterases as key to the enhanced ruminal digestion. FTIR analysis also suggested cross-link cell wall polymers as principal components of indigested fiber residues in feces. Based on structural information from enzymatic fingerprinting and FTIR, enzyme pretreatment to enhance glucose yield from barley straw and alfalfa hay upon exposure to mixed rumen-enzymes was developed. Prehydrolysis effects of recombinant fungal fibrolytic hydrolases were analyzed using microassay in combination with statistical experimental design. Recombinant hemicellulases and auxiliary enzymes initiated degradation of plant structural polysaccharides upon application and improved the in vitro saccharification of alfalfa and barley straw by mixed rumen enzymes. The validation results showed that microassay in combination with statistical experimental design can be successfully used to predict effective enzyme pretreatments that can enhance plant cell wall digestion by mixed rumen enzymes.
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