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Wang S, Xue Y, Zhang P, Yan Q, Li Y, Jiang Z. CRISPR/Cas9 System-Mediated Multi-copy Expression of an Alkaline Serine Protease in Aspergillus niger for the Production of XOD-Inhibitory Peptides. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:15194-15203. [PMID: 37807677 DOI: 10.1021/acs.jafc.3c04138] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
CRISPR/Cas9 system-mediated multi-copy expression of an alkaline serine protease (AoproS8) from Aspergillus oryzae was successfully built in Aspergillus niger. Furthermore, AoproS8 was continuously knocked in the glaA, amyA, and aamy gene loci in A. niger to construct multi-copy expression strains. The yield of the AoproS8 3.0 strain was 2.1 times higher than that of the AoproS8 1.0 strain. Then, a high protease activity of 11,023.2 U/mL with a protein concentration of 10.8 mg/mL was obtained through fed-batch fermentation in a 5 L fermenter. This is the first report on the high-level expression of alkaline serine proteases in A. niger. AoproS8 showed optimal activity at pH 9.0 and 40 °C. It was used for the production of xanthine oxidase (XOD)-inhibitory peptides from eight food processing protein by-products. Among them, the duck hemoglobin hydrolysates showed the highest XOD-inhibitory activity with an IC50 value of 2.39 mg/mL. Thus, our work provides a useful way for efficient expression of proteases in A. niger and high-value utilization of protein by-products.
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Affiliation(s)
- Shounan Wang
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Yibin Xue
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Peng Zhang
- College of Engineering, China Agricultural University, Beijing 100083, China
| | - Qiaojuan Yan
- College of Engineering, China Agricultural University, Beijing 100083, China
| | - Yanxiao Li
- College of Engineering, China Agricultural University, Beijing 100083, China
| | - Zhengqiang Jiang
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
- Food Laboratory of Zhongyuan, Luohe City 462000, Henan Province, China
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Liu D, Garrigues S, de Vries RP. Heterologous protein production in filamentous fungi. Appl Microbiol Biotechnol 2023:10.1007/s00253-023-12660-8. [PMID: 37405433 PMCID: PMC10386965 DOI: 10.1007/s00253-023-12660-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 06/16/2023] [Accepted: 06/21/2023] [Indexed: 07/06/2023]
Abstract
Filamentous fungi are able to produce a wide range of valuable proteins and enzymes for many industrial applications. Recent advances in fungal genomics and experimental technologies are rapidly changing the approaches for the development and use of filamentous fungi as hosts for the production of both homologous and heterologous proteins. In this review, we highlight the benefits and challenges of using filamentous fungi for the production of heterologous proteins. We review various techniques commonly employed to improve the heterologous protein production in filamentous fungi, such as strong and inducible promoters, codon optimization, more efficient signal peptides for secretion, carrier proteins, engineering of glycosylation sites, regulation of the unfolded protein response and endoplasmic reticulum associated protein degradation, optimization of the intracellular transport process, regulation of unconventional protein secretion, and construction of protease-deficient strains. KEY POINTS: • This review updates the knowledge on heterologous protein production in filamentous fungi. • Several fungal cell factories and potential candidates are discussed. • Insights into improving heterologous gene expression are given.
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Affiliation(s)
- Dujuan Liu
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Sandra Garrigues
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
- Department of Food Biotechnology, Instituto de Agroquímica Y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands.
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Wang L, Xie Y, Chang J, Wang J, Liu H, Shi M, Zhong Y. A novel sucrose-inducible expression system and its application for production of biomass-degrading enzymes in Aspergillus niger. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:23. [PMID: 36782304 PMCID: PMC9926565 DOI: 10.1186/s13068-023-02274-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Accepted: 01/30/2023] [Indexed: 02/15/2023]
Abstract
BACKGROUND Filamentous fungi are extensively exploited as important enzyme producers due to the superior secretory capability. However, the complexity of their secretomes greatly impairs the titer and purity of heterologous enzymes. Meanwhile, high-efficient evaluation and production of bulk enzymes, such as biomass-degrading enzymes, necessitate constructing powerful expression systems for bio-refinery applications. RESULTS A novel sucrose-inducible expression system based on the host strain Aspergillus niger ATCC 20611 and the β-fructofuranosidase promoter (PfopA) was constructed. A. niger ATCC 20611 preferentially utilized sucrose for rapid growth and β-fructofuranosidase production. Its secretory background was relatively clean because β-fructofuranosidase, the key enzyme responsible for sucrose utilization, was essentially not secreted into the medium and the extracellular protease activity was low. Furthermore, the PfopA promoter showed a sucrose concentration-dependent induction pattern and was not subject to glucose repression. Moreover, the strength of PfopA was 7.68-fold higher than that of the commonly used glyceraldehyde-3-phosphate dehydrogenase promoter (PgpdA) with enhanced green fluorescence protein (EGFP) as a reporter. Thus, A. niger ATCC 20611 coupled with the PfopA promoter was used as an expression system to express a β-glucosidase gene (bgla) from A. niger C112, allowing the production of β-glucosidase at a titer of 17.84 U/mL. The crude β-glucosidase preparation could remarkably improve glucose yield in the saccharification of pretreated corncob residues when added to the cellulase mixture of Trichoderma reesei QM9414. The efficacy of this expression system was further demonstrated by co-expressing the T. reesei-derived chitinase Chi46 and β-N-acetylglucosaminidase Nag1 to obtain an efficient chitin-degrading enzyme cocktail, which could achieve the production of N-acetyl-D-glucosamine from colloidal chitin with a conversion ratio of 91.83%. Besides, the purity of the above-secreted biomass-degrading enzymes in the crude culture supernatant was over 86%. CONCLUSIONS This PfopA-driven expression system expands the genetic toolbox of A. niger and broadens the application field of the traditional fructo-oligosaccharides-producing strain A. niger ATCC 20611, advancing it to become a high-performing enzyme-producing cell factory. In particular, the sucrose-inducible expression system possessed the capacity to produce biomass-degrading enzymes at a high level and evade endogenous protein interference, providing a potential purification-free enzyme production platform for bio-refinery applications.
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Affiliation(s)
- Lu Wang
- grid.27255.370000 0004 1761 1174State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237 People’s Republic of China
| | - Yijia Xie
- Qingdao Academy, Qingdao, 266111 People’s Republic of China
| | - Jingjing Chang
- grid.27255.370000 0004 1761 1174State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237 People’s Republic of China
| | - Juan Wang
- grid.27255.370000 0004 1761 1174State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237 People’s Republic of China
| | - Hong Liu
- grid.27255.370000 0004 1761 1174State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237 People’s Republic of China
| | - Mei Shi
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China.
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China.
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Zhao Y, Hao Q, Zhang Q, Yang Y, Ran C, Xu Q, Wu C, Liu W, Li S, Zhang Z, Zhou Z. Nuclease treatment enhanced the ameliorative effect of yeast culture on epidermal mucus, hepatic lipid metabolism, inflammation response and gut microbiota in high-fat diet-fed zebrafish. FISH & SHELLFISH IMMUNOLOGY 2022; 131:1182-1191. [PMID: 36403702 DOI: 10.1016/j.fsi.2022.11.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 11/13/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
As a functional feed additive, yeast cultures are rich in nucleotides, and adding extra nuclease can significantly increase the content of nucleotides in yeast culture. In this experiment, the effects on growth, epidermal mucus, liver and intestinal health of zebrafish were evaluated by supplementing the yeast culture or nuclease-treated yeast culture with a high-fat diet (HFD). One-month-old zebrafish were fed four diets: normal diet (NORM), HFD, yeast culture diet (YC), and nuclease-treated yeast culture diet (YC (N)) for three weeks. Results showed that the complement 4 activity of the epidermal mucus in YC (N) group was significantly higher than those in HFD and YC groups (P < 0.05). The YC and YC (N) significantly reduced the content of hepatic triglyceride caused by HFD (P < 0.05). Moreover, compared with the YC group, the YC (N) significantly increased the expression of lipolysis genes, such as PPARα, PGC1α, ACOX3 (P < 0.05). Compared with the YC group, the YC (N) group significantly increased the expression of liver pro-inflammatory factors TNFα, IL-6, IL-1β and anti-inflammatory factors TGFβ, IL-10 (P < 0.05). The diet YC and YC (N) significantly improved the height of the intestinal villus (P < 0.05). Compared with the HFD group, the YC (N) group significantly increased the expression of intestinal pro-inflammatory factors TNFα, IL-6 and anti-inflammatory factors TGFβ, IL-10 (P < 0.05). The YC (N) group significantly decreased the abundance of intestinal Proteobacteria and Acinetobacter, and increased the abundance of intestinal Actinobacteria, Mycobacterium and Rhodobacter (P < 0.05). In conclusion, compared with the supplement of yeast culture, nuclease treated yeast culture can further alleviate the adverse effects of HFD on liver and intestinal health, and be used as feed additives for the nutritional and immune regulation of fish.
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Affiliation(s)
- Yajie Zhao
- College of Life Science, Huzhou University, Huzhou, China; China -Norway Joint Lab on Fish Gut Microbiota, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qiang Hao
- China -Norway Joint Lab on Fish Gut Microbiota, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China; Norway-China Joint Lab on Fish Gut Microbiota, Institute of Biology, Norwegian University of Science and Technology, Trondheim, 7491, Norway
| | - Qingshuang Zhang
- China -Norway Joint Lab on Fish Gut Microbiota, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yalin Yang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture and Rural Affairs, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Chao Ran
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture and Rural Affairs, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Qiyou Xu
- College of Life Science, Huzhou University, Huzhou, China
| | - Chenglong Wu
- College of Life Science, Huzhou University, Huzhou, China
| | - Wenshu Liu
- Institute of Animal Husbandry and Veterinary, Jiangxi Academy of Agricultural Science, Nanchang, 330200, Jiangxi, China
| | - Siming Li
- Institute of Animal Husbandry and Veterinary, Jiangxi Academy of Agricultural Science, Nanchang, 330200, Jiangxi, China
| | - Zhen Zhang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture and Rural Affairs, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Zhigang Zhou
- College of Life Science, Huzhou University, Huzhou, China; China -Norway Joint Lab on Fish Gut Microbiota, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China; Institute of Animal Husbandry and Veterinary, Jiangxi Academy of Agricultural Science, Nanchang, 330200, Jiangxi, China.
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Wang S, Zhang P, Xue Y, Yan Q, Li X, Jiang Z. Characterization of a Novel Aspartic Protease from Rhizomucor miehei Expressed in Aspergillus niger and Its Application in Production of ACE-Inhibitory Peptides. Foods 2021; 10:foods10122949. [PMID: 34945499 PMCID: PMC8701012 DOI: 10.3390/foods10122949] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 11/19/2021] [Accepted: 11/22/2021] [Indexed: 11/16/2022] Open
Abstract
Rhizomucor miehei is an important fungus that produces aspartic proteases suitable for cheese processing. In this study, a novel aspartic protease gene (RmproB) was cloned from R. miehei CAU432 and expressed in Aspergillus niger. The amino acid sequence of RmproB shared the highest identity of 58.2% with the saccharopepsin PEP4 from Saccharomyces cerevisiae. High protease activity of 1242.2 U/mL was obtained through high density fermentation in 5 L fermentor. RmproB showed the optimal activity at pH 2.5 and 40 °C, respectively. It was stable within pH 1.5-6.5 and up to 45 °C. RmproB exhibited broad substrate specificity and had Km values of 3.16, 5.88, 5.43, and 1.56 mg/mL for casein, hemoglobin, myoglobin, and bovine serum albumin, respectively. RmproB also showed remarkable milk-clotting activity of 3894.1 SU/mg and identified the cleavage of Lys21-Ile22, Leu32-Ser33, Lys63-Pro64, Leu79-Ser80, Phe105-Met106, and Asp148-Ser149 bonds in κ-casein. Moreover, duck hemoglobin was hydrolyzed by RmproB to prepare angiotensin-I-converting enzyme (ACE) inhibitory peptides with high ACE-inhibitory activity (IC50 of 0.195 mg/mL). The duck hemoglobin peptides were further produced at kilo-scale with a yield of 62.5%. High-level expression and favorable biochemical characterization of RmproB make it a promising candidate for cheese processing and production of ACE-inhibitory peptides.
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Affiliation(s)
- Shounan Wang
- Department of Nutrition and Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (S.W.); (Y.X.)
| | - Peng Zhang
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Engineering, China Agricultural University, Beijing 100083, China; (P.Z.); (X.L.)
| | - Yibin Xue
- Department of Nutrition and Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (S.W.); (Y.X.)
| | - Qiaojuan Yan
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Engineering, China Agricultural University, Beijing 100083, China; (P.Z.); (X.L.)
- Correspondence: (Q.Y.); (Z.J.); Tel.: +86-10-6273-7689 (Z.J.); Fax: +86-10-8238-8508 (Z.J.)
| | - Xue Li
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Engineering, China Agricultural University, Beijing 100083, China; (P.Z.); (X.L.)
| | - Zhengqiang Jiang
- Department of Nutrition and Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (S.W.); (Y.X.)
- Correspondence: (Q.Y.); (Z.J.); Tel.: +86-10-6273-7689 (Z.J.); Fax: +86-10-8238-8508 (Z.J.)
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Paulino BN, Sales A, Felipe LDO, Pastore GM, Molina G, Bicas JL. Biotechnological production of non-volatile flavor compounds. Curr Opin Food Sci 2021. [DOI: 10.1016/j.cofs.2021.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Jiang C, Lv G, Tu Y, Cheng X, Duan Y, Zeng B, He B. Applications of CRISPR/Cas9 in the Synthesis of Secondary Metabolites in Filamentous Fungi. Front Microbiol 2021; 12:638096. [PMID: 33643273 PMCID: PMC7905030 DOI: 10.3389/fmicb.2021.638096] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 01/18/2021] [Indexed: 12/19/2022] Open
Abstract
Filamentous fungi possess the capacity to produce a wide array of secondary metabolites with diverse biological activities and structures, such as lovastatin and swainsonine. With the advent of the post-genomic era, increasing amounts of cryptic or uncharacterized secondary metabolite biosynthetic gene clusters are continually being discovered. However, owing to the longstanding lack of versatile, comparatively simple, and highly efficient genetic manipulation techniques, the broader exploration of industrially important secondary metabolites has been hampered thus far. With the emergence of CRISPR/Cas9-based genome editing technology, this dilemma may be alleviated, as this advanced technique has revolutionized genetic research and enabled the exploitation and discovery of new bioactive compounds from filamentous fungi. In this review, we introduce the CRISPR/Cas9 system in detail and summarize the latest applications of CRISPR/Cas9-mediated genome editing in filamentous fungi. We also briefly introduce the specific applications of the CRISPR/Cas9 system and CRISPRa in the improvement of secondary metabolite contents and discovery of novel biologically active compounds in filamentous fungi, with specific examples noted. Additionally, we highlight and discuss some of the challenges and deficiencies of using the CRISPR/Cas9-based genome editing technology in research on the biosynthesis of secondary metabolites as well as future application of CRISPR/Cas9 strategy in filamentous fungi are highlighted and discussed.
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Affiliation(s)
- Chunmiao Jiang
- Jiangxi Key Laboratory of Bioprocess Engineering and Co-Innovation Center for In-Vitro Diagnostic Reagents and Devices of Jiangxi Province, College of Life Sciences, Jiangxi Science and Technology Normal University, Nanchang, China
| | - Gongbo Lv
- Jiangxi Key Laboratory of Bioprocess Engineering and Co-Innovation Center for In-Vitro Diagnostic Reagents and Devices of Jiangxi Province, College of Life Sciences, Jiangxi Science and Technology Normal University, Nanchang, China
| | - Yayi Tu
- Jiangxi Key Laboratory of Bioprocess Engineering and Co-Innovation Center for In-Vitro Diagnostic Reagents and Devices of Jiangxi Province, College of Life Sciences, Jiangxi Science and Technology Normal University, Nanchang, China
| | - Xiaojie Cheng
- College of Life Sciences, Sichuan Normal University, Chengdu, China
| | - Yitian Duan
- School of Information, Renmin University of China, Beijing, China
| | - Bin Zeng
- Jiangxi Key Laboratory of Bioprocess Engineering and Co-Innovation Center for In-Vitro Diagnostic Reagents and Devices of Jiangxi Province, College of Life Sciences, Jiangxi Science and Technology Normal University, Nanchang, China.,College of Pharmacy, Shenzhen Technology University, Shenzhen, China
| | - Bin He
- Jiangxi Key Laboratory of Bioprocess Engineering and Co-Innovation Center for In-Vitro Diagnostic Reagents and Devices of Jiangxi Province, College of Life Sciences, Jiangxi Science and Technology Normal University, Nanchang, China
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Alves EM, Souza JFD, Macieja S, Oliva Neto PD. 5'-Ribonucleotides production using 5'-phosphodiesterase from spent malt roots. BRAZILIAN JOURNAL OF FOOD TECHNOLOGY 2021. [DOI: 10.1590/1981-6723.24620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Abstract 5'-ribonucleotides are high value-added molecules widely used in the food and pharmaceutical industries because of their bioactive properties. The present work aims to produce a composition of 5’-ribonucleotides using spent brewer’s yeast as cheap source of RNA, and barley malt rootlets as cheap source of 5'-phosphodiesterase (5'-PDE). This is a very promising and innovative strategy because both spent yeast and malt rootles are residues of the brewing process and are closely linked in a cycle that until now is not yet commercially exploited due to lack of studies. Our results showed that extraction of 5’-PDE was mainly influenced by the fineness of the rootlets and amount of extraction solvent (water). The main molecules formed during RNA hydrolysis were 5’-ribonucleotides, which represented 85.86% of the total hydrolyzed molecules. Finally, the results of the proposed approach can generate a new perspective for the brewing industry regarding the management of its wastes, generating from them products of high added value and with a wide range of applications.
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Affiliation(s)
| | | | - Szymon Macieja
- Universidade Estadual Paulista Júlio de Mesquita Filho, Brasil
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Improving expression of thermostable trehalase from Myceliophthora sepedonium in Aspergillus niger mediated by the CRISPR/Cas9 tool and its purification, characterization. Protein Expr Purif 2020; 165:105482. [DOI: 10.1016/j.pep.2019.105482] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 08/21/2019] [Accepted: 08/21/2019] [Indexed: 12/30/2022]
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High-level expression of highly active and thermostable trehalase from Myceliophthora thermophila in Aspergillus niger by using the CRISPR/Cas9 tool and its application in ethanol fermentation. J Ind Microbiol Biotechnol 2019; 47:133-144. [PMID: 31786675 DOI: 10.1007/s10295-019-02252-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 11/13/2019] [Indexed: 01/04/2023]
Abstract
Trehalase catalyzes the hydrolysis of the non-reducing disaccharide trehalose. The highly active trehalase MthT from Myceliophthora thermophila was screened from the trehalase genes of six species of filamentous fungi. An ingenious multi-copy knock-in expression strategy mediated by the CRISPR/Cas9 tool and medium optimization were used to improve MthT production in Aspergillus niger, up to 1698.83 U/mL. The protein background was dramatically abated due to insertion. The recombinant MthT showed optimal activity at pH 5.5 and 60 °C, and exhibited prominent thermal stability between 50 and 60 °C under acid conditions (pH 4.5-6.5). The ethanol conversion rate (ethanol yield/total glucose) was significantly improved by addition of MthT (51.88%) compared with MthT absence (34.38%), using 30% starch saccharification liquid. The results of this study provided an effective strategy, established a convenient platform for heterologous expression in A. niger and showed a potential strategy to decrease production costs in industrial ethanol production.
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Strategies for gene disruption and expression in filamentous fungi. Appl Microbiol Biotechnol 2019; 103:6041-6059. [DOI: 10.1007/s00253-019-09953-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/24/2019] [Accepted: 05/28/2019] [Indexed: 02/02/2023]
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