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Zhang T, Liu H, Lv B, Li C. Regulating Strategies for Producing Carbohydrate Active Enzymes by Filamentous Fungal Cell Factories. Front Bioeng Biotechnol 2020; 8:691. [PMID: 32733865 PMCID: PMC7360787 DOI: 10.3389/fbioe.2020.00691] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 06/03/2020] [Indexed: 12/17/2022] Open
Abstract
Filamentous fungi are important eukaryotic organisms crucial in substrate degradation and carbon cycle on the earth and have been harnessed as cell factories for the production of proteins and other high value-added products in recent decades. As cell factories, filamentous fungi play a crucial role in industrial protein production as both native hosts and heterologous hosts. In this review, the regulation strategies of carbohydrate active enzyme expression at both transcription level and protein level are introduced, and the transcription regulations are highlighted with induction mechanism, signaling pathway, and promoter and transcription factor regulation. Afterward, the regulation strategies in protein level including suitable posttranslational modification, protein secretion enhancement, and protease reduction are also presented. Finally, the challenges and perspectives in this field are discussed. In this way, a comprehensive knowledge regarding carbohydrate active enzyme production regulation at both transcriptional and protein levels is provided with the particular goal of aiding in the practical application of filamentous fungi for industrial protein production.
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Affiliation(s)
- Teng Zhang
- Institute for Synthetic Biosystem/Department of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, China
| | - Hu Liu
- Institute for Synthetic Biosystem/Department of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, China
| | - Bo Lv
- Institute for Synthetic Biosystem/Department of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, China
| | - Chun Li
- Institute for Synthetic Biosystem/Department of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Key Lab for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing, China
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Abdel-Azeem AM, Hasan GA, Mohesien MT. Biodegradation of Agricultural Wastes by Chaetomium Species. Fungal Biol 2020. [DOI: 10.1007/978-3-030-31612-9_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Liu G, Qu Y. Engineering of filamentous fungi for efficient conversion of lignocellulose: Tools, recent advances and prospects. Biotechnol Adv 2018; 37:519-529. [PMID: 30576717 DOI: 10.1016/j.biotechadv.2018.12.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 12/13/2018] [Accepted: 12/14/2018] [Indexed: 01/17/2023]
Abstract
Filamentous fungi, as the main producers of lignocellulolytic enzymes in industry, need to be engineered to improve the economy of large-scale lignocellulose conversion. Investigation of the cellular processes involved in lignocellulolytic enzyme production, as well as optimization of enzyme mixtures for higher hydrolysis efficiency, have provided effective targets for the engineering of lignocellulolytic fungi. Recently, the development of efficient genetic manipulation systems in several lignocellulolytic fungi opens up the possibility of systems engineering of these strains. Here, we review the recent progresses made in the engineering of lignocellulolytic fungi and highlight the research gaps in this area.
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Affiliation(s)
- Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China; Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, Qingdao 266237, China.
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Fang X, Qu Y. Metabolic Engineering of Fungal Strains for Efficient Production of Cellulolytic Enzymes. FUNGAL CELLULOLYTIC ENZYMES 2018:27-41. [PMCID: PMC7120360 DOI: 10.1007/978-981-13-0749-2_2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Filamentous fungi are widely used for production of cellulase and other cellulolytic enzymes. Metabolic engineering of filamentous fungal strains has been applied to improve enzyme production, and rapid progress has been made in the recent years. In this chapter, genetic tools and methods to develop superior enzyme producers are summarized, which includes establishment of genetic modification systems, selection and redesign of promoters, and metabolic engineering using either native transcription factors or artificial ones. In addition, enhancement of cellulase production through morphology engineering was also discussed. Emerging tools including CRISPR-Cas9-based genome editing and synthetic biology are highlighted, which are speeding up mechanisms elucidation and strain development, and will further facilitate economic cellulolytic enzyme production.
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Affiliation(s)
- Xu Fang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong China
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Zhang J, Wu C, Wang W, Wang W, Wei D. Construction of enhanced transcriptional activators for improving cellulase production in Trichoderma reesei RUT C30. BIORESOUR BIOPROCESS 2018; 5:40. [PMID: 32288986 PMCID: PMC7101855 DOI: 10.1186/s40643-018-0226-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 08/14/2018] [Indexed: 11/21/2022] Open
Abstract
Enhancing cellulase production in Trichoderma reesei is of great interest for an economical biorefinery. Artificial transcription factors are a potentially powerful molecular strategy for improving cellulase production in T. reesei. In this study, enhanced transcriptional activators XYR1VP, ACE2VP, and ACE1VP were constructed by linking the C terminus of XYR1, ACE2, or ACE1 with an activation domain of herpes simplex virus protein VP16. T. reesei transformants TXYR1VP, TACE2VP, and TACE1VP showed improved cellulase and/or xylanase production. TXYR1VP has a cellulase-free phenotype but with significantly elevated xylanase production. Xylanase I and xylanase II activities [U/(mg biomass)] increased by 51% and 80%, respectively, in TXYR1VP in comparison with parental strain RUT C30. The filter paper activity of TACE2VP in the Avicel-based medium increased by 52% compared to that of RUT C30. In the Avicel-based medium, TACE1VP manifested an 80% increase in FPase activity and a 50% increase in xylanase activity as compared to those of RUT C30. Additionally, when pretreated corn stover was hydrolyzed, crude enzymes produced from TACE1VP yielded a greater glucose release than did the enzymes produced by parental strain RUT C30.![]()
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Affiliation(s)
- Jiajia Zhang
- 1New World Institute of Biotechnology, State Key Lab of Bioreactor Engineering, East China University of Science and Technology, P.O.B. 311, 130 Meilong Road, Shanghai, 200237 China
| | - Chuan Wu
- 1New World Institute of Biotechnology, State Key Lab of Bioreactor Engineering, East China University of Science and Technology, P.O.B. 311, 130 Meilong Road, Shanghai, 200237 China
| | - Wei Wang
- 2State Key Lab of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237 China
| | - Wei Wang
- 1New World Institute of Biotechnology, State Key Lab of Bioreactor Engineering, East China University of Science and Technology, P.O.B. 311, 130 Meilong Road, Shanghai, 200237 China
| | - Dongzhi Wei
- 1New World Institute of Biotechnology, State Key Lab of Bioreactor Engineering, East China University of Science and Technology, P.O.B. 311, 130 Meilong Road, Shanghai, 200237 China
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Zhang J, Zhang G, Wang W, Wang W, Wei D. Enhanced cellulase production in Trichoderma reesei RUT C30 via constitution of minimal transcriptional activators. Microb Cell Fact 2018; 17:75. [PMID: 29773074 PMCID: PMC5956553 DOI: 10.1186/s12934-018-0926-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Accepted: 05/11/2018] [Indexed: 01/06/2023] Open
Abstract
Background Cellulase can convert lignocellulosic feedstocks into fermentable sugars, which can be used for the industrial production of biofuels and chemicals. The high cost of cellulase production remains a challenge for lignocellulose breakdown. Trichoderma reesei RUT C30 serves as a well-known industrial workhorse for cellulase production. Therefore, the enhancement of cellulase production by T. reesei RUT C30 is of great importance. Results Two sets of novel minimal transcriptional activators (DBDace2-VP16 and DBDcre1-VP16) were designed and expressed in T. reesei RUT C30. Expression of DBDace2-VP16 and DBDcre1-VP16 improved cellulase production under induction (avicel or lactose) and repression (glucose) conditions, respectively. The strain TMTA66 under avicel and TMTA139 under glucose with the highest cellulase activities outperformed other transformants and the parental strain under the corresponding conditions. For TMTA66 strains, the highest FPase activity was approximately 1.3-fold greater than that of the parental strain RUT C30 at 120 h of cultivation in a shake flask using avicel as the sole carbon source. The FPase activity (U/mg biomass) in TMTA139 strains was approximately 26.5-fold higher than that of the parental strain RUT C30 at 72 h of cultivation in a shake flask using glucose as the sole carbon source. Furthermore, the crude enzymes produced in the 7-L fermenter from TMTA66 and TMTA139 supplemented with commercial β-glucosidase hydrolyzed pretreated corn stover effectively. Conclusions These results show that replacing natural transcription factors with minimal transcriptional activators is a powerful strategy to enhance cellulase production in T. reesei. Our current study also offers an alternative genetic engineering strategy for the enhanced production of industrial products by other fungi. Electronic supplementary material The online version of this article (10.1186/s12934-018-0926-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jiajia Zhang
- State Key Lab of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China
| | - Guoxiu Zhang
- State Key Lab of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China
| | - Wei Wang
- State Key Lab of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Wei Wang
- State Key Lab of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China.
| | - Dongzhi Wei
- State Key Lab of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237, China
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Wu Y, Sun X, Xue X, Luo H, Yao B, Xie X, Su X. Overexpressing key component genes of the secretion pathway for enhanced secretion of an Aspergillus niger glucose oxidase in Trichoderma reesei. Enzyme Microb Technol 2017; 106:83-87. [DOI: 10.1016/j.enzmictec.2017.07.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 07/13/2017] [Accepted: 07/14/2017] [Indexed: 11/29/2022]
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Zhang X, Li Y, Zhao X, Bai F. Constitutive cellulase production from glucose using the recombinant Trichoderma reesei strain overexpressing an artificial transcription activator. BIORESOURCE TECHNOLOGY 2017; 223:317-322. [PMID: 27818160 DOI: 10.1016/j.biortech.2016.10.083] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 10/25/2016] [Accepted: 10/27/2016] [Indexed: 05/05/2023]
Abstract
The high cost of cellulase production presents biggest challenge in biomass deconstruction. Cellulase production by Trichoderma reesei using low cost carbon source is of great interest. In this study, an artificial transcription activator containing the Cre1 binding domain linked to the Xyr1 effector and binding domains was designed and constitutively overexpressed in T. reesei RUT C30. The recombinant strain T. reesei zxy-2 displayed constitutive cellulase production using glucose as a sole carbon source, and the production titer was 12.75-fold of that observed with T. reesei RUT C30 in shake flask culture. Moreover, FPase and xylanase titers of 2.63 and 108.72IU/mL, respectively, were achieved using glucose as sole carbon source within 48h in a 7-L fermenter by batch fermentation using T. reesei zxy-2. The crude enzyme obtained was used to hydrolyze alkali pretreated corn stover, and a high glucose yield of 99.18% was achieved.
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Affiliation(s)
- Xiaoyue Zhang
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116023, China
| | - Yonghao Li
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116023, China
| | - Xinqing Zhao
- State Key Laboratory of Microbial Metabolism & School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Fengwu Bai
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116023, China; State Key Laboratory of Microbial Metabolism & School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
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Liu G, Qin Y, Li Z, Qu Y. Development of highly efficient, low-cost lignocellulolytic enzyme systems in the post-genomic era. Biotechnol Adv 2013; 31:962-75. [PMID: 23507038 DOI: 10.1016/j.biotechadv.2013.03.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 03/09/2013] [Accepted: 03/10/2013] [Indexed: 11/19/2022]
Abstract
The current high cost of lignocellulolytic enzymes is a major bottleneck in the economic bioconversion of lignocellulosic biomass to fuels and chemicals. Fungal lignocellulolytic enzyme systems are secreted at high levels, making them the most promising starting points for further development of highly efficient lignocellulolytic enzyme systems. In this paper, recent advances in improvement of fungal lignocellulolytic enzyme systems are reviewed, with an emphasis on the achievements made using genomic approaches. A general strategy for lignocellulolytic enzyme system development is proposed, including the improvement of the hydrolysis efficiencies and productivities of current enzyme systems. The applications of genomic, transcriptomic and proteomic analysis methods in examining the composition of native enzyme systems, discovery of novel enzymes and synergistic proteins from natural sources, and understanding of regulatory mechanisms for lignocellulolytic enzyme biosynthesis are summarized. By combining systems biology and synthetic biology tools, engineered fungal strains are expected to produce high levels of optimized lignocellulolytic enzyme systems.
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Affiliation(s)
- Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China
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Cellulolytic Enzyme Production and Enzymatic Hydrolysis for Second-Generation Bioethanol Production. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2012; 128:1-24. [DOI: 10.1007/10_2011_131] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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