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Gaizauskaite Z, Zvirdauskiene R, Svazas M, Basinskiene L, Zadeike D. Optimised Degradation of Lignocelluloses by Edible Filamentous Fungi for the Efficient Biorefinery of Sugar Beet Pulp. Polymers (Basel) 2024; 16:1178. [PMID: 38732647 PMCID: PMC11085495 DOI: 10.3390/polym16091178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 04/17/2024] [Accepted: 04/18/2024] [Indexed: 05/13/2024] Open
Abstract
The degradation of the complex structure of lignocellulosic biomass is important for its further biorefinery to value-added bioproducts. The use of effective fungal species for the optimised degradation of biomass can promote the effectiveness of the biorefinery of such raw material. In this study, the optimisation of processing parameters (temperature, time, and s/w ratio) for cellulase activity and reducing sugar (RS) production through the hydrolysis of sugar beet pulp (SBP) by edible filamentous fungi of Aspergillus, Fusarium, Botrytis, Penicillium, Rhizopus, and Verticillium spp. was performed. The production of RS was analysed at various solid/water (s/w) ratios (1:10-1:20), different incubation temperatures (20-35 °C), and processing times (60-168 h). The Aspergillus niger CCF 3264 and Penicillium oxalicum CCF 3438 strains showed the most effective carboxymethyl cellulose (CMC) degrading activity and also sugar recovery (15.9-44.8%) from SBP biomass in the one-factor experiments. Mathematical data evaluation indicated that the highest RS concentration (39.15 g/100 g d.w.) and cellulolytic activity (6.67 U/g d.w.) could be achieved using A. niger CCF 3264 for the degradation of SBP at 26 °C temperature with 136 h of processing time and a 1:15 solid/water ratio. This study demonstrates the potential of fungal degradation to be used for SBP biorefining.
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Affiliation(s)
- Zydrune Gaizauskaite
- Department of Food Science and Technology, Faculty of Chemical Technology, Kaunas University of Technology, 50254 Kaunas, Lithuania; (R.Z.); (L.B.)
- Food Institute, Kaunas University of Technology, 50254 Kaunas, Lithuania
| | - Renata Zvirdauskiene
- Department of Food Science and Technology, Faculty of Chemical Technology, Kaunas University of Technology, 50254 Kaunas, Lithuania; (R.Z.); (L.B.)
| | - Mantas Svazas
- Department of Applied Economics, Finance and Accounting, Agriculture Academy of Vytautas Magnus University, 53361 Kaunas, Lithuania;
| | - Loreta Basinskiene
- Department of Food Science and Technology, Faculty of Chemical Technology, Kaunas University of Technology, 50254 Kaunas, Lithuania; (R.Z.); (L.B.)
| | - Daiva Zadeike
- Department of Food Science and Technology, Faculty of Chemical Technology, Kaunas University of Technology, 50254 Kaunas, Lithuania; (R.Z.); (L.B.)
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Chen Y, Wang J, Wang M, Han A, Zhao X, Wang W, Wei D. Engineering the metabolism and morphology of the filamentous fungus Trichoderma reesei for efficient L-malic acid production. BIORESOURCE TECHNOLOGY 2023; 387:129629. [PMID: 37558099 DOI: 10.1016/j.biortech.2023.129629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 07/27/2023] [Accepted: 08/03/2023] [Indexed: 08/11/2023]
Abstract
L-malic acid (MA) is a vital platform chemical with huge market demand because of its broad industrial applications. A cell factory for MA production was engineered by strengthening the intrinsic pathway without inserting foreign genes into Trichoderma reesei. The native MA transporter gene in the T. reesei genome was characterized (trmae1), and its overexpression significantly improved MA production, which increased from 2 to 56.24 g/L. Native pyruvate carboxylase, malate dehydrogenase, malic enzyme, and glucose transporter were overexpressed further to improve the titer and yield of MA production. Fungal morphology was adapted to produce MA in the fermenter by deleting gul1. A titer of 235.8 g/L MA was produced from the final engineered strain in a 5-L fermenter with a yield of 1.48 mol of MA per mol of glucose and productivity of 1.23 g/L/h. This study provides novel insights for understanding and remodeling the MA synthesis pathway.
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Affiliation(s)
- Yumeng Chen
- State Key Lab of Bioreactor Engineering, 130 Meilong Road, Shanghai, China; Luhua Suo, East China University of Science and Technology, Shanghai 200237, China
| | - Jiajia Wang
- State Key Lab of Bioreactor Engineering, 130 Meilong Road, Shanghai, China; Luhua Suo, East China University of Science and Technology, Shanghai 200237, China
| | - Meng Wang
- State Key Lab of Bioreactor Engineering, 130 Meilong Road, Shanghai, China
| | - Ao Han
- State Key Lab of Bioreactor Engineering, 130 Meilong Road, Shanghai, China
| | | | - Wei Wang
- State Key Lab of Bioreactor Engineering, 130 Meilong Road, Shanghai, China; Luhua Suo, East China University of Science and Technology, Shanghai 200237, China.
| | - Dongzhi Wei
- State Key Lab of Bioreactor Engineering, 130 Meilong Road, Shanghai, China; Luhua Suo, East China University of Science and Technology, Shanghai 200237, China
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Luu XC, Shida Y, Suzuki Y, Kuwahara D, Fujimoto T, Takahashi Y, Sato N, Nakamura A, Ogasawara W. Ultrahigh-throughput screening of Trichoderma reesei strains capable of carbon catabolite repression release and cellulase hyperproduction using a microfluidic droplet platform. Biosci Biotechnol Biochem 2023; 87:1393-1406. [PMID: 37550222 DOI: 10.1093/bbb/zbad108] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 07/28/2023] [Indexed: 08/09/2023]
Abstract
Trichoderma reesei is the most well-known cellulase producer in the biorefinery industry. Its cellulase biosynthesis is repressed by glucose via carbon catabolite repression (CCR), making CCR-releasing strains with cellulase hyperproduction desirable. Here, we employed a microfluidic droplet platform to culture and screen T. reesei mutants capable of CCR release and cellulase overproduction from extensive mutagenesis libraries. With 3 mutagenesis rounds, about 6.20 × 103 droplets were sorted from a population of 1.51 × 106 droplets in a period of 4.4 h; 76 recovery mutants were screened on flask fermentation, and 2 glucose uptake retarded mutants, MG-9-3 and MG-9-3-30, were eventually isolated. We also generated a hypercellulase producer, M-5, with CCR release via a single mutagenesis round. The hyphal morphology and molecular mechanisms in the mutants were analyzed. This versatile approach combined with a comprehensive understanding of CCR release mechanisms will provide innovative and effective strategies for low-cost cellulase production.
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Affiliation(s)
- Xuan Chinh Luu
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Yosuke Shida
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Yoshiyuki Suzuki
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Daiki Kuwahara
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Takeshi Fujimoto
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Yuka Takahashi
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Naomi Sato
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Akihiro Nakamura
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Wataru Ogasawara
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
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Dey P, Chakrabortty S, Haldar D, Rangarajan V, Ashok S. On-site enriched production of cellulase enzyme using rice straw waste and its hydrolytic performance evaluation through systematic dynamic modeling. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:36710-36727. [PMID: 36562976 DOI: 10.1007/s11356-022-24797-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
The application of on-site produced cellulolytic enzymes in place of commercial enzymes towards hydrolytic preparations of reducing sugars using inexpensive lignocellulosic wastes is considered the most efficient strategy to accomplish a cost-effective biofuel production process. Along with improved production, intrinsic and systematic performance evaluation of the produced enzyme during the hydrolysis process through kinetic intervention remains a crucial requirement for achieving the improved performance of the process. With this motivation, the present study primarily deals with the nutritionally optimized production strategy of cellulases from rice straw (RS) waste using Trichoderma reesei (MTCC 164). The highest cellulase production was obtained 8.09 ± 0.32 g/l in batch mode at optimized combinations of 3.5% (w/v) RS inducer, 3.0% (w/v) lactose, and 1.5% (w/v) peptone. Production was further improved through pH-regulated (pH 5.5 to 6.5) fed-batch fermentations. The enzyme produced at pH 6 was considered for hydrolysis studies at 4 to 10% (w/w) solid loading due to reasonable exoglucanase, endoglucanase, and maximum β-glucosidase activity levels of 9.3 U/ml, 3.87 U/ml, and 2.65 U/ml respectively. Multi-reaction systematic kinetic modeling was implemented to evaluate enzyme performance during hydrolysis, and the values of inhibitory kinetic parameters (K2r = 7.1 < K1r = 18.5 < K3r = 276.6) suggested that sequential conversion of cellulose to glucose by existing enzyme components was more dominant over direct conversion.
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Affiliation(s)
- Pinaki Dey
- Department of Biotechnology, Karunya Institute of Technology and Sciences, Coimbatore, Tamil Nadu, 641114, India.
| | - Sankha Chakrabortty
- School of Chemical Engineering, Kalinga Institute of Industrial Technology, Bhubaneswar, 751024, India
| | - Dibyajyoti Haldar
- Department of Biotechnology, Karunya Institute of Technology and Sciences, Coimbatore, Tamil Nadu, 641114, India
| | - Vivek Rangarajan
- Department of Chemical Engineering, BITS Pilani, KK Birla Goa Campus, Pilani, Goa, 403726, India
| | - Sowmya Ashok
- Department of Biotechnology, Karunya Institute of Technology and Sciences, Coimbatore, Tamil Nadu, 641114, India
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Wang H, Pang AP, Li B, Huo L, Wu FG, Lin F. Intracellular Sugar Transporters Facilitate Cellulase Synthesis in Trichoderma reesei Using Lactose. Biomolecules 2023; 13:biom13020295. [PMID: 36830663 PMCID: PMC9953249 DOI: 10.3390/biom13020295] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/28/2022] [Accepted: 01/31/2023] [Indexed: 02/09/2023] Open
Abstract
Sugar transporters play an important role in the cellulase production of lignocellulose-degrading fungi. Nevertheless, the role and function of these transporters are still unclear. Here we first report intracellular sugar transporters assisting cellulase production in Trichoderma reesei (T. reesei) using lactose. The mRNA levels of sugar transporter genes mfs, gst, and lac1 were substantially upregulated in T. reesei cultivated on lactose, with the most abundant mRNA levels at 24 h as compared to glucose. Moreover, the individual deletion of these sugar transporters significantly inhibited cellulase production, solid cell growth, and sporulation of T. reesei, suggesting they play a supporting role in cellulase production when grown in lactose. Surprisingly, MFS, GST, and LAC1 were mainly localized in the cytoplasm, with MFS and LAC1 in the endoplasmic reticulum (ER), representing the first discovery of intracellular sugar transporters involved in cellulase biosynthesis in lactose culture. The absence of the gene lac1 noticeably inhibited most of the crucial genes related to cellulase production, including cellulase-encoding genes, transcription factors, and sugar transporters, at 24 h, which was fully relieved at 48 h or 72 h, indicating that lac1 affects cellulase production more at the early step. This research advances the understanding of the function of intracellular sugar transporters in fungi, particularly for fungal cellulase production.
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Affiliation(s)
- Haiyan Wang
- State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Tianjin 300453, China
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Ai-Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Bingzhi Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Liujie Huo
- Helmholtz International Laboratory, State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Fu-Gen Wu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Fengming Lin
- State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Tianjin 300453, China
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
- Correspondence:
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Castro-Ochoa LD, Hernández-Leyva SR, Medina-Godoy S, Gómez-Rodríguez J, Aguilar-Uscanga MG, Castro-Martínez C. Integration of agricultural residues as biomass source to saccharification bioprocess and for the production of cellulases from filamentous fungi. 3 Biotech 2023; 13:43. [PMID: 36643402 PMCID: PMC9834466 DOI: 10.1007/s13205-022-03444-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 12/17/2022] [Indexed: 01/13/2023] Open
Abstract
The production of second-generation bioethanol has several challenges, among them finding cheap and efficient enzymes for a sustainable process. In this work, we analyzed two native fungi, Cladosporium cladosporioides and Penicillium funiculosum, as a source of cellulolytic enzyme production, and corn stover, wheat bran, chickpeas, and bean straw as a carbon source in two fermentation systems: submerged and solid fermentation. Corn stover was selected for cellulase production in both fermentation systems, because we found the highest enzymatic activities when carboxymethyl cellulase activity (CMCase) was assessed using CMC as substrate. C. cladosporioides showed the highest CMCase activity (1.6 U/mL), while P. funiculosum had the highest filter paper activity (Fpase) (0.39 U/mL). The ß-glucosidase activities produced by both fungi were similar in submerged fermentation using corn stover as substrate. Through in-gel zymography, three polypeptides with cellulolytic activities were identified in each fungus: with molecular weights of ~ 38, 45 and 70 kDa in C. cladosporioides and ~ 21, 63 and 100 kDa in P. funiculosum. The best results for saccharification (10.11 g/L of reducing sugars) of diluted acid pretreated corn stover were obtained after 36 h of the hydrolytic process at pH 5 and 50 °C using the enzyme extract of P. funiculosum. This is the first report of cellulase identification in C. cladosporioides and the saccharification of corn stover using enzymes of this fungus. Enzymatic extracts of C. cladosporioides and P. funiculosum obtained from low-cost lignocellulosic biomass have great potential for use in the production of second-generation bioethanol.
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Affiliation(s)
- Lelie Denise Castro-Ochoa
- Departamento de Biotecnología Agrícola, Instituto Politécnico Nacional, CIIDIR Sinaloa, Blvd. Juan de Dios Bátiz Paredes No. 250. Col. San Joachin, CP 81101 Guasave, Sinaloa México
| | - Sandy Rocío Hernández-Leyva
- Departamento de Biotecnología Agrícola, Instituto Politécnico Nacional, CIIDIR Sinaloa, Blvd. Juan de Dios Bátiz Paredes No. 250. Col. San Joachin, CP 81101 Guasave, Sinaloa México
| | - Sergio Medina-Godoy
- Departamento de Biotecnología Agrícola, Instituto Politécnico Nacional, CIIDIR Sinaloa, Blvd. Juan de Dios Bátiz Paredes No. 250. Col. San Joachin, CP 81101 Guasave, Sinaloa México
| | - Javier Gómez-Rodríguez
- Tecnológico Nacional de México, Instituto Tecnológico de Veracruz, Unidad de Investigación y Desarrollo de Alimentos (UNIDA), H. Veracruz, México
| | - María Guadalupe Aguilar-Uscanga
- Tecnológico Nacional de México, Instituto Tecnológico de Veracruz, Unidad de Investigación y Desarrollo de Alimentos (UNIDA), H. Veracruz, México
| | - Claudia Castro-Martínez
- Departamento de Biotecnología Agrícola, Instituto Politécnico Nacional, CIIDIR Sinaloa, Blvd. Juan de Dios Bátiz Paredes No. 250. Col. San Joachin, CP 81101 Guasave, Sinaloa México
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Patel VK, Das A, Kumari R, Kajla S. In silico Analysis of Diverse Endo-β-1,4-glucanases Reveals Their Molecular Evolution. J EVOL BIOCHEM PHYS+ 2023. [DOI: 10.1134/s0022093023010088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
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Cai W, Chen Y, Zhang L, Fang X, Wang W. A three-gene cluster in Trichoderma reesei reveals a potential role of dmm2 in DNA repair and cellulase production. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:34. [PMID: 35351200 PMCID: PMC8966179 DOI: 10.1186/s13068-022-02132-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 03/19/2022] [Indexed: 12/03/2022]
Abstract
Background The ascomycete Trichoderma reesei is one of the most efficient industrial producers of cellulase. Gene targeting by homologous recombination is a key technique for improving strains and constructing mutants. In T. reesei, tku70 (homologous to human KU70) was deleted to block non-homologous end-joining, which led to 95% of transformants exhibiting homologous recombination. Results Two genes located in close proximity to tku70 were identified: the ferrochelatase gene hem8 (tre78582, homologous to Aspergillus niger hemH and Cryptococcus neoformans HEM15) and a putative DNA methylation modulator-2 gene dmm2 (tre108087, homologous to Neurospora crassa dmm-2). Genome-wide surveys of 324 sequenced fungal genomes revealed that the homologues of the three genes of interest are encoded in tandem in most Sordariomycetes. The expression of this three-gene cluster is regulated by blue light. The roles of these three genes were analyzed via deletion and complementation tests. The gene hem8 was originally described as a novel and highly distinct auxotrophic marker in T. reesei and we found that the product protein, HEM8, catalyzes the final step in heme biosynthesis from highly photoreactive porphyrins. The lethal phenotype of the hem8 deletion could be overcome by hematin supplementation. We also studied the functions of tku70 and dmm2 in DNA repair using mutagen sensitivity experiments. We found that the Δtku70 strain showed increased sensitivity to bleomycin, which induces DNA double-strand breaks, and that the Δdmm2 strain was sensitive to bleomycin, camptothecin (an inhibitor of type I topoisomerases), and hydroxyurea (a deoxynucleotide synthesis inhibitor). The double-mutant Δtku70&dmm2 showed higher sensitivity to hydroxyurea, camptothecin, and bleomycin than either of the single mutants. Knockout of dmm2 significantly increased cellulase production. Conclusions Our data show, for the first time, that ferrochelatase encoded by hem8 catalyzes the final step in heme biosynthesis from highly photoreactive porphyrins and that dmm2 encodes a putative DNA methylation modulator-2 protein related to DNA repair and cellulase expression in T. reesei. Our data provide important insights into the roles of this three-gene cluster in T. reesei and other Sordariomycetes and show that the DNA methylation modulator DMM2 affects cellulase gene expression in T. reesei. Supplementary Information The online version contains supplementary material available at 10.1186/s13068-022-02132-y.
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Wang H, Pang AP, Wang W, Li B, Li C, Wu FG, Lin F. Discovery of ER-localized sugar transporters for cellulase production with lac1 being essential. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:132. [PMID: 36443855 PMCID: PMC9706901 DOI: 10.1186/s13068-022-02230-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 11/12/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND In the process of cellulose hydrolysis, carbohydrate hydrolysates are transported into cells through membrane transporters, and then affect the expression of cellulase-encoding genes. Sugar transporters play a crucial role in cellulase production in lignocellulolytic fungi, of which relatively few have been functionally validated to date and are all reported to be on cell membrane. RESULT Through transcriptome analysis and qRT-PCR, three putative MFS sugar transporters GST, MFS, and LAC1 were found to display significantly higher mRNA levels in T. reesei grown on cellulose than on glucose. The individual deletion of these three genes compromised cellulase production and delayed sugar absorption by 24 h in T. reesei. Nevertheless, they transported pretty low level of sugars, including galactose, lactose, and mannose, and did not transport glucose, when expressed in yeast system. Meanwhile, all three transporters were unexpectedly found to be intracellular, being located in endoplasmic reticulum (ER). Particularly, the knockout of lac1 almost abolished cellulase production, and significantly inhibited biomass generation regardless of sugar types, indicating that lac1 is essential for cellulase production and biomass formation. The absence of lac1 upregulated genes involved in ribosome biogenesis, while downregulated genes in cellulase production, protein processing in ER (particularly protein glycosylation), and lipid biosynthesis. The inhibition of lac1 deletion on the transcriptional levels of genes related to cellulase biosynthesis was restored after 72 h, but the cellulase production was still inhibited, indicating lac1 might pose a post-transcription regulation on cellulase production that are independent on the known cellulase regulation mediated by CRT1 and XYR1. CONCLUSION For the first time, intracellular sugar transporters (mfs, gst, and lac1) facilitating cellulase production were identified, which was distributed in ER. Their sugar transporting ability was very weak, indicating that they might be related to sugar utilization inside cells rather than the cellular sugar uptake. More importantly, sugar transporter lac1 is first found to be essential for cellulase production and biomass formation by affecting protein processing in ER (particularly protein glycosylation) and lipid biosynthesis. The effect of LAC1 on cellulase production seems to be post-transcriptional at late stage of cellulase production, independent on the well-known cellulase regulation mediated by CRT1 and XYR1. These findings improve the understanding of intracellular sugar transporters in fungi and their important role in cellulase synthesis.
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Affiliation(s)
- Haiyan Wang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Ai-Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Wei Wang
- State Key Lab of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai, China
| | - Bingzhi Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Chengcheng Li
- School of Light Ind. & Food Sci. and Joint International Research Lab of Lignocellulosic Functional Materials, Nanjing Forestry University, Nanjing, 210037, China
| | - Fu-Gen Wu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Fengming Lin
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China.
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Borin GP, Oliveira JVDC. Assessing the intracellular primary metabolic profile of Trichoderma reesei and Aspergillus niger grown on different carbon sources. FRONTIERS IN FUNGAL BIOLOGY 2022; 3:998361. [PMID: 37746225 PMCID: PMC10512294 DOI: 10.3389/ffunb.2022.998361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 08/29/2022] [Indexed: 09/26/2023]
Abstract
Trichoderma reesei and Aspergillus niger are efficient biological platforms for the production of various industrial products, including cellulases and organic acids. Nevertheless, despite the extensive research on these fungi, integrated analyses of omics-driven approaches are still missing. In this study, the intracellular metabolic profile of T. reesei RUT-C30 and A. niger N402 strains grown on glucose, lactose, carboxymethylcellulose (CMC), and steam-exploded sugarcane bagasse (SEB) as carbon sources for 48 h was analysed by proton nuclear magnetic resonance. The aim was to verify the changes in the primary metabolism triggered by these substrates and use transcriptomics data from the literature to better understand the dynamics of the observed alterations. Glucose and CMC induced higher fungal growth whereas fungi grown on lactose showed the lowest dry weight. Metabolic profile analysis revealed that mannitol, trehalose, glutamate, glutamine, and alanine were the most abundant metabolites in both fungi regardless of the carbon source. These metabolites are of particular interest for the mobilization of carbon and nitrogen, and stress tolerance inside the cell. Their concomitant presence indicates conserved mechanisms adopted by both fungi to assimilate carbon sources of different levels of recalcitrance. Moreover, the higher levels of galactose intermediates in T. reesei suggest its better adaptation in lactose, whereas glycolate and malate in CMC might indicate activation of the glyoxylate shunt. Glycerol and 4-aminobutyrate accumulated in A. niger grown on CMC and lactose, suggesting their relevant role in these carbon sources. In SEB, a lower quantity and diversity of metabolites were identified compared to the other carbon sources, and the metabolic changes and higher xylanase and pNPGase activities indicated a better utilization of bagasse by A. niger. Transcriptomic analysis supported the observed metabolic changes and pathways identified in this work. Taken together, we have advanced the knowledge about how fungal primary metabolism is affected by different carbon sources, and have drawn attention to metabolites still unexplored. These findings might ultimately be considered for developing more robust and efficient microbial factories.
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Affiliation(s)
- Gustavo Pagotto Borin
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), São Paulo, Brazil
- Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Juliana Velasco de Castro Oliveira
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), São Paulo, Brazil
- Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), São Paulo, Brazil
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Kinetic model supported improved and optimized submerged production strategy of cellulase enzyme from newspaper waste biomass. Bioprocess Biosyst Eng 2022; 45:1281-1295. [PMID: 35750867 DOI: 10.1007/s00449-022-02741-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Accepted: 06/03/2022] [Indexed: 11/02/2022]
Abstract
A systematic evaluation of microorganism's potential towards biosynthesis of cellulases from inexpensive lignocellulosic feedstock through appropriate kinetic modelling facilitates understanding, optimization and designing of an effective industrial cellulase enzyme production process. The present study aims to optimize a submerged fungal cultivation strategy for cellulase production from abundantly available newspaper wastes (NPW). A combined pretreatment strategy consisting diluted, 1% (v v-1) H2SO4 followed by 2% (w v-1) NaOH treatment was highly effective to convert newspaper waste to an effective cellulose-enriched inducer for the production of cellulase. In addition, the composition of the most influential nutrient components like peptone and lactose was optimized with the help of response surface methodology for enhanced cellulase production with maximum activity levels. Maximum cellulase production of 8.64 g L-1 with 7.82 FPU mL-1 total activity levels was achieved from optimized composition of pretreated NPW 3.29% (w v-1), lactose 2.94% (w v-1) and peptone 1.53% (w v-1). To analyse intrinsic inhibition effect of the substrate concentration on cellulase production, modified Luedeking-Piret model simulated experiments were further conducted with 1.5% (w/v), 3.29% (w/v) and 4% (w/v) NPW concentrations. The developed kinetic model perfectly captured the trends of biomass production, substrate consumption and adsorption characteristic of cellulase enzyme on its activity during production. The rate constant for cellulase synthesis was evaluated to be increased to 0.040 IU g-1 h -1 at 3.29% (w v-1) of NPW concentration; however, it was further reduced to 0.024 IU g-1 h -1 at higher NPW concentration of 4% (w v-1).
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Pang AP, Luo Y, Hu X, Zhang F, Wang H, Gao Y, Durrani S, Li C, Shi X, Wu FG, Li BZ, Lu Z, Lin F. Transmembrane transport process and endoplasmic reticulum function facilitate the role of gene cel1b in cellulase production of Trichoderma reesei. Microb Cell Fact 2022; 21:90. [PMID: 35590356 PMCID: PMC9118834 DOI: 10.1186/s12934-022-01809-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 04/30/2022] [Indexed: 11/16/2022] Open
Abstract
Background A total of 11 β-glucosidases are predicted in the genome of Trichoderma reesei, which are of great importance for regulating cellulase biosynthesis. Nevertheless, the relevant function and regulation mechanism of each β-glucosidase remained unknown. Results We evidenced that overexpression of cel1b dramatically decreased cellulase synthesis in T. reesei RUT-C30 both at the protein level and the mRNA level. In contrast, the deletion of cel1b did not noticeably affect cellulase production. Protein CEL1B was identified to be intracellular, being located in vacuole and cell membrane. The overexpression of cel1b reduced the intracellular pNPGase activity and intracellular/extracellular glucose concentration without inducing carbon catabolite repression. On the other hand, RNA-sequencing analysis showed the transmembrane transport process and endoplasmic reticulum function were affected noticeably by overexpressing cel1b. In particular, some important sugar transporters were notably downregulated, leading to a compromised cellular uptake of sugars including glucose and cellobiose. Conclusions Our data suggests that the cellulase inhibition by cel1b overexpression was not due to the β-glucosidase activity, but probably the dysfunction of the cellular transport process (particularly sugar transport) and endoplasmic reticulum (ER). These findings advance the knowledge of regulation mechanism of cellulase synthesis in filamentous fungi, which is the basis for rationally engineering T. reesei strains to improve cellulase production in industry. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01809-1.
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Affiliation(s)
- Ai-Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Yongsheng Luo
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Xin Hu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Funing Zhang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Haiyan Wang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Yichen Gao
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Samran Durrani
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Chengcheng Li
- International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, China
| | - Xiaotong Shi
- International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, China
| | - Fu-Gen Wu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Bing-Zhi Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Zuhong Lu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China.
| | - Fengming Lin
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China.
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Yang Z, Hu X, Zhang F, Durrani S, Zhang J, Pang AP, Gao Y, Wu FG, Lin F. Chitosan-modified fluorescent dye for simple, fast, and in-situ measurement of fungal cell growth in the presence of insoluble compounds. FEMS Microbiol Lett 2022; 369:6884137. [PMID: 36481926 DOI: 10.1093/femsle/fnac118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/24/2022] [Accepted: 12/02/2022] [Indexed: 12/13/2022] Open
Abstract
The measurement of fungal cell growth in submerged culture systems containing insoluble compounds is essential yet difficult due to the interferences from the insoluble compounds like biopolymers. Here, we developed a fluorescent strategy based on chitosan-modified fluorescein isothiocyanate (GC-FITC) to monitor the cell growth of lignocellulosic fungi cultivated on biopolymers. GC-FITC could stain only lignocellulosic fungi (Tricoderma reesei, Penicillium oxalicum, Aspergillus nidulans, and Neurospora crassa), but not biopolymers (cellulose, xylan, pectin, or lignin), excluding the interferences from these insoluble biopolymer. Moreover, a linear relationship was observed between the fluorescence intensity of GC-FITC absorbed by lignocellulosic fungi and the biomass of lignocellulosic fungi. Therefore, GC-FITC was leveraged to monitor the cell growth of lignocellulosic fungi when using biopolymers like cellulose as the carbon sources, which is faster, more convenient, time-saving, and cost-effective than the existing methods using protein/DNA content measurement. GC-FITC offers a powerful tool to detect fungal growth in culture systems with insoluble materials.
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Affiliation(s)
- Zihuayuan Yang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Xin Hu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Funing Zhang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Samran Durrani
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Jie Zhang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Ai-Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Yichen Gao
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Fu-Gen Wu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Fengming Lin
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
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Yan S, Xu Y, Yu XW. From induction to secretion: a complicated route for cellulase production in Trichoderma reesei. BIORESOUR BIOPROCESS 2021; 8:107. [PMID: 38650205 PMCID: PMC10991602 DOI: 10.1186/s40643-021-00461-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 10/16/2021] [Indexed: 11/10/2022] Open
Abstract
The filamentous fungus Trichoderma reesei has been widely used for cellulase production that has extensive applications in green and sustainable development. Increasing costs and depletion of fossil fuels provoke the demand for hyper-cellulase production in this cellulolytic fungus. To better manipulate T. reesei for enhanced cellulase production and to lower the cost for large-scale fermentation, it is wise to have a comprehensive understanding of the crucial factors and complicated biological network of cellulase production that could provide new perspectives for further exploration and modification. In this review, we summarize recent progress and give an overview of the cellular process of cellulase production in T. reesei, including the carbon source-dependent cellulase induction, complicated transcriptional regulation network, and efficient protein assembly and trafficking. Among that, the key factors involved in cellulase production were emphasized, shedding light on potential perspectives for further engineering.
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Affiliation(s)
- Su Yan
- Lab of Brewing Microbiology and Applied Enzymology, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China
| | - Yan Xu
- Lab of Brewing Microbiology and Applied Enzymology, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China
| | - Xiao-Wei Yu
- Lab of Brewing Microbiology and Applied Enzymology, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China.
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China.
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Pang AP, Zhang F, Hu X, Luo Y, Wang H, Durrani S, Wu FG, Li BZ, Zhou Z, Lu Z, Lin F. Glutamine involvement in nitrogen regulation of cellulase production in fungi. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:199. [PMID: 34645509 PMCID: PMC8513308 DOI: 10.1186/s13068-021-02046-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 09/23/2021] [Indexed: 05/27/2023]
Abstract
BACKGROUND Cellulase synthesized by fungi can environment-friendly and sustainably degrades cellulose to fermentable sugars for producing cellulosic biofuels, biobased medicine and fine chemicals. Great efforts have been made to study the regulation mechanism of cellulase biosynthesis in fungi with the focus on the carbon sources, while little attention has been paid to the impact and regulation mechanism of nitrogen sources on cellulase production. RESULTS Glutamine displayed the strongest inhibition effect on cellulase biosynthesis in Trichoderma reesei, followed by yeast extract, urea, tryptone, ammonium sulfate and L-glutamate. Cellulase production, cell growth and sporulation in T. reesei RUT-C30 grown on cellulose were all inhibited with the addition of glutamine (a preferred nitrogen source) with no change for mycelium morphology. This inhibition effect was attributed to both L-glutamine itself and the nitrogen excess induced by its presence. In agreement with the reduced cellulase production, the mRNA levels of 44 genes related to the cellulase production were decreased severely in the presence of glutamine. The transcriptional levels of genes involved in other nitrogen transport, ribosomal biogenesis and glutamine biosynthesis were decreased notably by glutamine, while the expression of genes relevant to glutamate biosynthesis, amino acid catabolism, and glutamine catabolism were increased noticeably. Moreover, the transcriptional level of cellulose signaling related proteins ooc1 and ooc2, and the cellular receptor of rapamycin trFKBP12 was increased remarkably, whose deletion exacerbated the cellulase depression influence of glutamine. CONCLUSION Glutamine may well be the metabolite effector in nitrogen repression of cellulase synthesis, like the role of glucose plays in carbon catabolite repression. Glutamine under excess nitrogen condition repressed cellulase biosynthesis significantly as well as cell growth and sporulation in T. reesei RUT-C30. More importantly, the presence of glutamine notably impacted the transport and metabolism of nitrogen. Genes ooc1, ooc2, and trFKBP12 are associated with the cellulase repression impact of glutamine. These findings advance our understanding of nitrogen regulation of cellulase production in filamentous fungi, which would aid in the rational design of strains and fermentation strategies for cellulase production in industry.
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Affiliation(s)
- Ai-Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Funing Zhang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Xin Hu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Yongsheng Luo
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Haiyan Wang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Samran Durrani
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Fu-Gen Wu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Bing-Zhi Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Zhihua Zhou
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Zuhong Lu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Fengming Lin
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
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Chen Y, Wang W, Liu P, Lin A, Fan X, Wu C, Li N, Wei L, Wei D. The novel repressor Rce2 competes with Ace3 to regulate cellulase gene expression in the filamentous fungus Trichoderma reesei. Mol Microbiol 2021; 116:1298-1314. [PMID: 34608686 DOI: 10.1111/mmi.14825] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/22/2021] [Accepted: 09/27/2021] [Indexed: 11/29/2022]
Abstract
The filamentous fungus Trichoderma reesei is widely used for industrial cellulase production. In T. reesei, cellulase gene expression is tightly controlled by a regulatory network involving multiple transcription factors. Here, we isolated a novel protein, Rce2, using a pull-down assay and mass spectrometry analysis, from a partial carbon catabolite de-repression mutant, T. reesei Rut-C30, cultured under glucose-repressing conditions. Deletion and overexpression of Rce2 in T. reesei wild-type QM6a and mutant Rut-C30 revealed that Rce2 acts as a repressor of cellulase gene expression. DNase I footprinting assays, electrophoretic mobility shift assays, and chromatin immunoprecipitation assays revealed that Rce2 was located in the nucleus and bound to the consensus sequences 5'-(T/A)NNNNCCG-3' and 5'-CGGNNNN(T/A)-3' in the promoters of cellulase-related genes to repress their transcription. Additionally, Rce2 antagonized Ace3 binding to the cbh1 promoter to repress its transcription. However, Rce2 was not involved in Cre1-mediated carbon catabolite repression. These results demonstrate the mechanism through which Rce2 represses the expression of cellulase genes and provide novel insights into the regulatory system of cellulases and methods that can be used for the regulation of gene expression in T. reesei.
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Affiliation(s)
- Yumeng Chen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Wei Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Pei Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Aibo Lin
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Xingjia Fan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Chuan Wu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Ni Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Liujing Wei
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Dongzhi Wei
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
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Fang H, Li C, Zhao J, Zhao C. Biotechnological Advances and Trends in Engineering Trichoderma reesei towards Cellulase Hyperproducer. BIOTECHNOL BIOPROC E 2021. [DOI: 10.1007/s12257-020-0243-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Li Y, Yu J, Zhang P, Long T, Mo Y, Li J, Li Q. Comparative transcriptome analysis of Trichoderma reesei reveals different gene regulatory networks induced by synthetic mixtures of glucose and β-disaccharide. BIORESOUR BIOPROCESS 2021; 8:57. [PMID: 38650287 PMCID: PMC10991369 DOI: 10.1186/s40643-021-00411-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/26/2021] [Indexed: 11/10/2022] Open
Abstract
The mixture of glucose and β-disaccharide (MGD) synthesized by transglycosylation of glucose as a low-cost soluble carbon source can efficiently induce cellulase production in Trichoderma reesei, which holds potential for the biorefining of lignocellulosic biomass. However, it is not yet fully understood how MGD induces T. reesei cellulase. In this study, transcriptomic analyses were conducted to investigate the molecular basis of MGD for lignocellulose-degrading enzyme production of T. reesei Rut C30 compared with that on lactose. Particular attention was paid to CAZymes, transcription factors, transporters and other protein processing pathways related to lignocellulose degradation. As a result, MGD can elicit transcription of GH5-, GH6- and GH7-encoding cellulases that is up to 1.4-fold higher than that induced by lactose, but GH11- and GH74-encoding xylanases are downregulated by 1.7- and 4.4-fold, respectively. Gene expression profiles suggest that the transcription activators xyr1 and vib1 are significantly upregulated and that the mitogen-activated protein kinase pathway is strengthened compared to the case of lactose induction. In addition, hac1-encoding UPR-specific transcription factors are significantly upregulated by MGD, which may be enhanced due to proper folding and processing of nascent proteins. These findings provide a theoretical basis for further understanding the characterization of efficient cellulase production using MGD as an inducer in T. reesei and offer potential strategies for strain improvement.
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Affiliation(s)
- Yonghao Li
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China.
| | - Jingze Yu
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Peng Zhang
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Tingting Long
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Yi Mo
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Jianghong Li
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Qian Li
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
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Ammonium Ions Induce Cellulase Synthesis in Trichoderma koningii. Curr Microbiol 2021; 78:3201-3211. [PMID: 34213616 DOI: 10.1007/s00284-021-02568-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 06/02/2021] [Indexed: 10/21/2022]
Abstract
Cellulase plays an important role in addressing the issue of the energy crisis. However, the yield and degradation efficiency of cellulase remain a major challenge. In the present study, we aimed to verify whether ammonium ion (NH4+) could induce cellulase synthesis from T. koningii AS3.2774 and to explore new functional genes related to the cellulase production. Our results indicated that NH4+ induces cellulase production in a way different from nitrogen sources. NH4+-mediated mycelia displayed a significant increase in transport vesicles. Under NH4+ mediation, CBHI, CBHII, glycoside hydrolase family 5 proteins, Hap2/3/5 complexes, "ribosome biogenesis", and "heme binding" were significantly up-regulated, and differentially expressed genes (DEGs) were mainly involved in "Metabolism". Collectively, our findings illustrated that NH4+ induced the cellulase production at morphological and gene expression levels, which might be related to the Hap2/3/5 complex, ribosomes, and genes involved in various amino acid metabolism, pyruvate metabolism, and glycolysis/gluconeogenesis. Taken together, our results provided valuable insights into the regulatory network of cellulase gene expression in filamentous fungi.
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Droplet-based microfluidic platform for high-throughput screening of Streptomyces. Commun Biol 2021; 4:647. [PMID: 34059751 PMCID: PMC8166820 DOI: 10.1038/s42003-021-02186-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 05/05/2021] [Indexed: 12/20/2022] Open
Abstract
Streptomyces are one of the most important industrial microorganisms for the production of proteins and small-molecule drugs. Previously reported flow cytometry-based screening methods can only screen spores or protoplasts released from mycelium, which do not represent the filamentous stationary phase Streptomyces used in industrial cultivation. Here we show a droplet-based microfluidic platform to facilitate more relevant, reliable and rapid screening of Streptomyces mycelium, and achieved an enrichment ratio of up to 334.2. Using this platform, we rapidly characterized a series of native and heterologous constitutive promoters in Streptomyces lividans 66 in droplets, and efficiently screened out a set of engineered promoter variants with desired strengths from two synthetic promoter libraries. We also successfully screened out several hyperproducers of cellulases from a random S. lividans 66 mutant library, which had 69.2–111.4% greater cellulase production than the wild type. Our method provides a fast, simple, and powerful solution for the industrial engineering and screening of Streptomyces in more industry-relevant conditions. Streptomyces are an important filamentous bacterium genus in industry, but most of the high-throughput techniques so far can only separate spores or protoplasts. Tu et al. develop an encapsulating method that allows screening of Streptomyces in the filamentous, stationary phase.
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Buffo MM, Ferreira ALZ, Almeida RMRG, Farinas CS, Badino AC, Ximenes EA, Ladisch MR. Cellulolytic enzymes production guided by morphology engineering. Enzyme Microb Technol 2021; 149:109833. [PMID: 34311878 DOI: 10.1016/j.enzmictec.2021.109833] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/11/2021] [Accepted: 05/19/2021] [Indexed: 11/26/2022]
Abstract
Endoglucanase and xylanase are critical enzymes for liquefaction and enzyme hydrolysis of high solids lignocellulosic biomass to facilitate its transport and production of desired derived products. Here is reported how combinations of different spore concentrations and pH influence microbial morphology, and how this may be used to direct expression and secretion of enzymes by Aspergillus niger. While xylanase production is not affected by A. niger morphology changes, endoglucanase production is enhanced under conditions of lower stress and by morphology that results in pellets. β-glucosidase production is enhanced under dispersed morphology, which results in up to fourfold increase of this enzyme production under the tested experimental conditions. A morphologic scale (Y) is proposed based on a form factor that considers the size and frequency of each morphology class, and that points to conditions that result in high selectivity for either endoglucanase or β-glucosidase production. An equation proposed to relate enzyme activity to morphology provides a useful tool for tuning enzyme production of A. niger, where morphology is a first indication of relative enzyme activities in a fermentation broth.
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Affiliation(s)
- Mariane M Buffo
- Federal University of São Carlos, São Carlos, SP, 13565-905, Brazil
| | | | | | - Cristiane S Farinas
- Federal University of São Carlos, São Carlos, SP, 13565-905, Brazil; Embrapa Instrumentation, Rua XV de Novembro 1452, São Carlos, SP, 13560-970, Brazil
| | - Alberto C Badino
- Federal University of São Carlos, São Carlos, SP, 13565-905, Brazil.
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Abstract
Trichoderma reesei has 11 putative β-glucosidases in its genome, playing key parts in the induction and production of cellulase. Nevertheless, the reason why the T. reesei genome encodes so many β-glucosidases and the distinct role each β-glucosidase plays in cellulase production remain unknown. In the present study, the cellular function and distribution of 10 known β-glucosidases (CEL3B, CEL3E, CEL3F, CEL3H, CEL3J, CEL1A, CEL3C, CEL1B, CEL3G, and CEL3D) were explored in T. reesei, leaving out BGL1 (CEL3A), which has been well investigated. We found that the overexpression of cel3b or cel3g significantly enhanced extracellular β-glucosidase production, whereas the overexpression of cel1b severely inhibited cellulase production by cellulose, resulting in nearly no growth of T. reesei. Four types of cellular distribution patterns were observed for β-glucosidases in T. reesei: (i) CEL3B, CEL3E, CEL3F, and CEL3G forming clearly separated protein secretion vesicles in the cytoplasm; (ii) CEL3H and CEL3J diffusing the whole endomembrane as well as the cell membrane with protein aggregation, like a reticular network; (iii) CEL1A and CEL3D in vacuoles; (iv) and CEL3C in the nucleus. β-glucosidases CEL1A, CEL3B, CEL3E, CEL3F, CEL3G, CEL3H, and CEL3J were identified as extracellular, CEL3C and CEL3D as intracellular, and CEL1B as unknown. The extracellular β-glucosidases CEL3B, CEL3E, CEL3F, CEL3H, and CEL3G were secreted through a tip-directed conventional secretion pathway, and CEL1A, via a vacuole-mediated pathway that was achieved without any signal peptide, while CEL3J was secreted via an unconventional protein pathway bypassing the endoplasmic reticulum (ER) and Golgi.
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Yan S, Xu Y, Yu XW. Rational engineering of xylanase hyper-producing system in Trichoderma reesei for efficient biomass degradation. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:90. [PMID: 33832521 PMCID: PMC8033665 DOI: 10.1186/s13068-021-01943-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 03/27/2021] [Indexed: 05/27/2023]
Abstract
BACKGROUND Filamentous fungus Trichoderma reesei has been widely used as a workhorse for cellulase and xylanase productions. Xylanase has been reported as the crucial accessory enzyme in the degradation of lignocellulose for higher accessibility of cellulase. In addition, the efficient hydrolysis of xylan needs the co-work of multiple xylanolytic enzymes, which rise an increasing demand for the high yield of xylanase for efficient biomass degradation. RESULTS In this study, a xylanase hyper-producing system in T. reesei was established by tailoring two transcription factors, XYR1 and ACE1, and homologous overexpression of the major endo-xylanase XYNII. The expressed xylanase cocktail contained 5256 U/mL xylanase activity and 9.25 U/mL β-xylosidase (pNPXase) activity. Meanwhile, the transcription level of the xylanolytic genes in the strain with XYR1 overexpressed was upregulated, which was well correlated with the amount of XYR1-binding sites. In addition, the higher expression of associated xylanolytic enzymes would result in more efficient xylan hydrolysis. Besides, 2310-3085 U/mL of xylanase activities were achieved using soluble carbon source, which was more efficient and economical than the traditional strategy of xylan induction. Unexpectedly, deletion of ace1 in C30OExyr1 did not give any improvement, which might be the result of the disturbed function of the complex formed between ACE1 and XYR1. The enzymatic hydrolysis of alkali pretreated corn stover using the crude xylanase cocktails as accessory enzymes resulted in a 36.64% increase in saccharification efficiency with the ratio of xylanase activity vs FPase activity at 500, compared to that using cellulase alone. CONCLUSIONS An efficient and economical xylanase hyper-producing platform was developed in T. reesei RUT-C30. The novel platform with outstanding ability for crude xylanase cocktail production would greatly fit in biomass degradation and give a new perspective of further engineering in T. reesei for industrial purposes.
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Affiliation(s)
- Su Yan
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China
| | - Yan Xu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China
| | - Xiao-Wei Yu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China.
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Pang AP, Wang H, Zhang F, Hu X, Wu FG, Zhou Z, Wang W, Lu Z, Lin F. High-dose rapamycin exerts a temporary impact on T. reesei RUT-C30 through gene trFKBP12. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:77. [PMID: 33771193 PMCID: PMC8004424 DOI: 10.1186/s13068-021-01926-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 03/11/2021] [Indexed: 05/15/2023]
Abstract
BACKGROUND Knowledge with respect to regulatory systems for cellulase production is prerequisite for exploitation of such regulatory networks to increase cellulase production, improve fermentation efficiency and reduce the relevant production cost. The target of rapamycin (TOR) signaling pathway is considered as a central signaling hub coordinating eukaryotic cell growth and metabolism with environmental inputs. However, how and to what extent the TOR signaling pathway and rapamycin are involved in cellulase production remain elusive. RESULT At the early fermentation stage, high-dose rapamycin (100 μM) caused a temporary inhibition effect on cellulase production, cell growth and sporulation of Trichoderma reesei RUT-C30 independently of the carbon sources, and specifically caused a tentative morphology defect in RUT-C30 grown on cellulose. On the contrary, the lipid content of T. reesei RUT-C30 was not affected by rapamycin. Accordingly, the transcriptional levels of genes involved in the cellulase production were downregulated notably with the addition of rapamycin. Although the mRNA levels of the putative rapamycin receptor trFKBP12 was upregulated significantly by rapamycin, gene trTOR (the downstream effector of the rapamycin-FKBP12 complex) and genes associated with the TOR signaling pathways were not changed markedly. With the deletion of gene trFKBP12, there is no impact of rapamycin on cellulase production, indicating that trFKBP12 mediates the observed temporary inhibition effect of rapamycin. CONCLUSION Our study shows for the first time that only high-concentration rapamycin induced a transient impact on T. reesei RUT-C30 at its early cultivation stage, demonstrating T. reesei RUT-C30 is highly resistant to rapamycin, probably due to that trTOR and its related signaling pathways were not that sensitive to rapamycin. This temporary influence of rapamycin was facilitated by gene trFKBP12. These findings add to our knowledge on the roles of rapamycin and the TOR signaling pathways play in T. reesei.
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Affiliation(s)
- Ai-Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Haiyan Wang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Funing Zhang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Xin Hu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Fu-Gen Wu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Zhihua Zhou
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Wei Wang
- State Key Lab of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai, China
| | - Zuhong Lu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Fengming Lin
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
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Chen Y, Fan X, Zhao X, Shen Y, Xu X, Wei L, Wang W, Wei D. cAMP activates calcium signalling via phospholipase C to regulate cellulase production in the filamentous fungus Trichoderma reesei. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:62. [PMID: 33685506 PMCID: PMC7941909 DOI: 10.1186/s13068-021-01914-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 02/21/2021] [Indexed: 05/15/2023]
Abstract
BACKGROUND The filamentous fungus Trichoderma reesei is one of the best producers of cellulase and has been widely studied for the production of cellulosic ethanol and bio-based products. We previously reported that Mn2+ and N,N-dimethylformamide (DMF) can stimulate cellulase overexpression via Ca2+ bursts and calcium signalling in T. reesei under cellulase-inducing conditions. To further understand the regulatory networks involved in cellulase overexpression in T. reesei, we characterised the Mn2+/DMF-induced calcium signalling pathway involved in the stimulation of cellulase overexpression. RESULTS We found that Mn2+/DMF stimulation significantly increased the intracellular levels of cAMP in an adenylate cyclase (ACY1)-dependent manner. Deletion of acy1 confirmed that cAMP is crucial for the Mn2+/DMF-stimulated cellulase overexpression in T. reesei. We further revealed that cAMP elevation induces a cytosolic Ca2+ burst, thereby initiating the Ca2+ signal transduction pathway in T. reesei, and that cAMP signalling causes the Ca2+ signalling pathway to regulate cellulase production in T. reesei. Furthermore, using a phospholipase C encoding gene plc-e deletion strain, we showed that the plc-e gene is vital for cellulase overexpression in response to stimulation by both Mn2+ and DMF, and that cAMP induces a Ca2+ burst through PLC-E. CONCLUSIONS The findings of this study reveal the presence of a signal transduction pathway in which Mn2+/DMF stimulation produces cAMP. Increase in the levels of cAMP activates the calcium signalling pathway via phospholipase C to regulate cellulase overexpression under cellulase-inducing conditions. These findings provide insights into the molecular mechanism of the cAMP-PLC-calcium signalling pathway underlying cellulase expression in T. reesei and highlight the potential applications of signal transduction in the regulation of gene expression in fungi.
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Affiliation(s)
- Yumeng Chen
- 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
| | - Xingjia Fan
- 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
| | - Xinqing Zhao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yaling Shen
- 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
| | - Xiangyang Xu
- Zaozhuang Jie Nuo Enzyme Co. Ltd., Shandong, China
| | - Liujing 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
| | - 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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Alarcón E, Hernández C, García G, Ziarelli F, Gutiérrez-Rivera B, Musule R, Vázquez-Marrufo G, Gardner TG. Changes in chemical and structural composition of sugarcane bagasse caused by alkaline pretreatments [Ca(OH)2 and NaOH] modify the amount of endoglucanase and β-glucosidase produced by Aspergillus niger in solid-state fermentation. CHEM ENG COMMUN 2021. [DOI: 10.1080/00986445.2021.1881777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Enrique Alarcón
- Instituto de Biotecnología y Ecología Aplicada (INBIOTECA), Universidad Veracruzana, Xalapa, Mexico
| | - Christian Hernández
- Instituto de Biotecnología y Ecología Aplicada (INBIOTECA), Universidad Veracruzana, Xalapa, Mexico
| | - Gabriela García
- Instituto de Biotecnología y Ecología Aplicada (INBIOTECA), Universidad Veracruzana, Xalapa, Mexico
| | - Fabio Ziarelli
- Faculty of Science and Technology of Saint-Jérôme, Aix Marseille University, Marseille, France
| | | | - Ricardo Musule
- Escuela Nacional de Estudios Superiores, Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Mexico
| | - Gerardo Vázquez-Marrufo
- Centro Multidisciplinario de Estudios en Biotecnología (CMEB), Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Michoacán, Mexico
| | - Terrence G. Gardner
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, USA
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Shibata N, Kakeshita H, Igarashi K, Takimura Y, Shida Y, Ogasawara W, Koda T, Hasunuma T, Kondo A. Disruption of alpha-tubulin releases carbon catabolite repression and enhances enzyme production in Trichoderma reesei even in the presence of glucose. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:39. [PMID: 33557925 PMCID: PMC7869464 DOI: 10.1186/s13068-021-01887-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 01/19/2021] [Indexed: 05/05/2023]
Abstract
BACKGROUND Trichoderma reesei is a filamentous fungus that is important as an industrial producer of cellulases and hemicellulases due to its high secretion of these enzymes and outstanding performance in industrial fermenters. However, the reduction of enzyme production caused by carbon catabolite repression (CCR) has long been a problem. Disruption of a typical transcriptional regulator, Cre1, does not sufficiently suppress this reduction in the presence of glucose. RESULTS We found that deletion of an α-tubulin (tubB) in T. reesei enhanced both the amount and rate of secretory protein production. Also, the tubulin-disrupted (ΔtubB) strain had high enzyme production and the same enzyme profile even if the strain was cultured in a glucose-containing medium. From transcriptome analysis, the ΔtubB strain exhibited upregulation of both cellulase and hemicellulase genes including some that were not originally induced by cellulose. Moreover, cellobiose transporter genes and the other sugar transporter genes were highly upregulated, and simultaneous uptake of glucose and cellobiose was also observed in the ΔtubB strain. These results suggested that the ΔtubB strain was released from CCR. CONCLUSION Trichoderma reesei α-tubulin is involved in the transcription of cellulase and hemicellulase genes, as well as in CCR. This is the first report of overcoming CCR by disrupting α-tubulin gene in T. reesei. The disruption of α-tubulin is a promising approach for creating next-generation enzyme-producing strains of T. reesei.
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Affiliation(s)
- Nozomu Shibata
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640-8580, Japan
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, Hyogo, 657-8501, Japan
| | - Hiroshi Kakeshita
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640-8580, Japan
| | - Kazuaki Igarashi
- Biological Science Research, Kao Corporation, 2606 Akabane, Ichikai, Haga, Tochigi, 321-3497, Japan
| | - Yasushi Takimura
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640-8580, Japan
| | - Yosuke Shida
- Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Wataru Ogasawara
- Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Tohru Koda
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, Hyogo, 657-8501, Japan
| | - Tomohisa Hasunuma
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, Hyogo, 657-8501, Japan.
- Engineering Biology Research Center, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, Hyogo, 657-8501, Japan.
| | - Akihiko Kondo
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, Hyogo, 657-8501, Japan
- Engineering Biology Research Center, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, Hyogo, 657-8501, Japan
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501, Japan
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29
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Papzan Z, Kowsari M, Javan-Nikkhah M, Gohari AM, Limón MC. Strain improvement of Trichoderma spp. through two-step protoplast fusion for cellulase production enhancement. Can J Microbiol 2020; 67:406-414. [PMID: 33226848 DOI: 10.1139/cjm-2020-0438] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Fungal protoplast fusion is an approach to introduce novel characteristics into industrially important strains. Cellulases, essential enzymes with a wide range of biotechnological applications, are produced by many species of the filamentous fungi Trichoderma. In this study, a collection of 60 natural isolates were screened for Avicel and carboxymethyl cellulose degradation, and two cellulase producers of Trichoderma virens and Trichoderma harzianum were used for protoplast fusion. One of the resulting hybrids with improved cellulase activity, C1-3, was fused with the hyperproducer Trichoderma reesei Rut-C30. A new selected hybrid, F7, was increased in cellulase activity 1.8 and 5 times in comparison with Rut-C30 and C1-3, respectively. The increases in enzyme activity correlated with an upregulation of the cellulolytic genes cbh1, cbh2, egl3, and bgl1 in the parents. The amount of mRNA of cbh1 and cbh2 in F7 resembled that of Rut-C30 while the bgl1 mRNA level was similar to that of C1-3. AFLP (amplified fragment length polymorphism) fingerprinting and GC-MS (gas chromatography - mass spectrometry) analysis represented variations in parental strains and fusants. In conclusion, the results demonstrate that a 3-interspecific hybrid strain was isolated, with improved characteristics for cellulase degradation and showing genetic polymorphisms and differences in the volatile profile, suggesting reorganizations at the genetic level.
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Affiliation(s)
- Zahra Papzan
- Department of Biotechnology, Faculty of Agricultural Sciences and Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.,Department of Genetics, Faculty of Biology, University of Seville, Seville 41012, Spain
| | - Mojegan Kowsari
- Microbial Biotechnology Department, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research, Education and Extension Organization (AREEO), Shahid Fahmideh Boulevard, P.O. Box 31535-1897, Karaj, Iran
| | - Mohammad Javan-Nikkhah
- Department of Plant Pathology, Faculty of Agricultural Sciences and Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Amir Mirzadi Gohari
- Department of Plant Pathology, Faculty of Agricultural Sciences and Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - M Carmen Limón
- Department of Genetics, Faculty of Biology, University of Seville, Seville 41012, Spain
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Zheng F, Yang R, Cao Y, Zhang W, Lv X, Meng X, Zhong Y, Chen G, Zhou Q, Liu W. Engineering Trichoderma reesei for Hyperproduction of Cellulases on Glucose to Efficiently Saccharify Pretreated Corncobs. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:12671-12682. [PMID: 33140639 DOI: 10.1021/acs.jafc.0c04663] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The filamentous fungus Trichoderma reesei (teleomorph Hypocrea jecorina) is widely used as a cellulase producer in the industry. Herein, we describe the rational engineering of the publicly available T. reesei QM9414 strain to achieve a remarkable high-level production of cellulase on glucose. Overexpression of the key cellulase regulator XYR1 by the copper-repressible promoter Ptcu1 was first implemented to achieve a full cellulase production in the context of catabolite repression (CCR) while eliminating the requirement of inducing sugars for enzyme production. The T. reesei bgl1 gene was further overexpressed to compensate for its low β-glucosidase activity on glucose. This overexpression resulted in a 102% increase in FPase activity compared with the CCR-released RUT-C30 strain cultured on Avicel. Moreover, the saccharification efficiency toward pretreated corncob residues by crude enzymes from the engineered strain on glucose increased by 85% compared with that treated by enzymes from RUT-C30 cultivated on Avicel. The engineered T. reesei strain thus shows great potential as a viable alternative to deliver commercial cellulases after further optimization for efficient saccharification of agricultural waste.
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Affiliation(s)
- Fanglin Zheng
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, No.72 Binhai Road, Qingdao, Shandong 266237, P. R. China
| | - Renfei Yang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, No.72 Binhai Road, Qingdao, Shandong 266237, P. R. China
| | - Yanli Cao
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, No.72 Binhai Road, Qingdao, Shandong 266237, P. R. China
| | - Weixin Zhang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, No.72 Binhai Road, Qingdao, Shandong 266237, P. R. China
| | - Xinxing Lv
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, No.72 Binhai Road, Qingdao, Shandong 266237, P. R. China
| | - Xiangfeng Meng
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, No.72 Binhai Road, Qingdao, Shandong 266237, P. R. China
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, No.72 Binhai Road, Qingdao, Shandong 266237, P. R. China
| | - Guanjun Chen
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, No.72 Binhai Road, Qingdao, Shandong 266237, P. R. China
| | - Qingxin Zhou
- Shandong Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing Technology of Shandong Province/Key Laboratory of Novel Food Resources Processing, Ministry of Agriculture and Rural Affairs, Institute of Agro-Food Science and Technology, No.202 Gongye North Road, Jinan 250100, P. R. China
- College of Life Science, Shandong Normal University, No.88 Wenhua East Road, Jinan 250014, P. R. China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, No.72 Binhai Road, Qingdao, Shandong 266237, P. R. China
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Buffo MM, Esperança MN, Farinas CS, Badino AC. Relation between pellet fragmentation kinetics and cellulolytic enzymes production by Aspergillus niger in conventional bioreactor with different impellers. Enzyme Microb Technol 2020; 139:109587. [DOI: 10.1016/j.enzmictec.2020.109587] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 04/07/2020] [Accepted: 04/24/2020] [Indexed: 10/24/2022]
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Quantitative Proteome Profiling Reveals Cellobiose-Dependent Protein Processing and Export Pathways for the Lignocellulolytic Response in Neurospora crassa. Appl Environ Microbiol 2020; 86:AEM.00653-20. [PMID: 32471912 DOI: 10.1128/aem.00653-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/12/2020] [Indexed: 12/22/2022] Open
Abstract
Filamentous fungi are intensively used for producing industrial enzymes, including lignocellulases. Employing insoluble cellulose to induce the production of lignocellulases causes some drawbacks, e.g., a complex fermentation operation, which can be overcome by using soluble inducers such as cellobiose. Here, a triple β-glucosidase mutant of Neurospora crassa, which prevents rapid turnover of cellobiose and thus allows the disaccharide to induce lignocellulases, was applied to profile the proteome responses to cellobiose and cellulose (Avicel). Our results revealed a shared proteomic response to cellobiose and Avicel, whose elements included lignocellulases and cellulolytic product transporters. While the cellulolytic proteins showed a correlated increase in protein and mRNA levels, only a moderate correlation was observed on a proteomic scale between protein and mRNA levels (R 2 = 0.31). Ribosome biogenesis and rRNA processing were significantly overrepresented in the protein set with increased protein but unchanged mRNA abundances in response to Avicel. Ribosome biogenesis, as well as protein processing and protein export, was also enriched in the protein set that showed increased abundance in response to cellobiose. NCU05895, a homolog of yeast CWH43, is potentially involved in transferring a glycosylphosphatidylinositol (GPI) anchor to nascent proteins. This protein showed increased abundance but no significant change in mRNA levels. Disruption of CWH43 resulted in a significant decrease in cellulase activities and secreted protein levels in cultures grown on Avicel, suggesting a positive regulatory role for CWH43 in cellulase production. The findings should have an impact on a systems engineering approach for strain improvement for the production of lignocellulases.IMPORTANCE Lignocellulases are important industrial enzymes for sustainable production of biofuels and bio-products. Insoluble cellulose has been commonly used to induce the production of lignocellulases in filamentous fungi, which causes a difficult fermentation operation and enzyme loss due to adsorption to cellulose. The disadvantages can be overcome by using soluble inducers, such as the disaccharide cellobiose. Quantitative proteome profiling of the model filamentous fungus Neurospora crassa revealed cellobiose-dependent pathways for cellulase production, including protein processing and export. A protein (CWH43) potentially involved in protein processing was found to be a positive regulator of lignocellulase production. The cellobiose-dependent mechanisms provide new opportunities to improve the production of lignocellulases in filamentous fungi.
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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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Mazzoli R. Metabolic engineering strategies for consolidated production of lactic acid from lignocellulosic biomass. Biotechnol Appl Biochem 2020; 67:61-72. [DOI: 10.1002/bab.1869] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 12/05/2019] [Indexed: 01/04/2023]
Affiliation(s)
- Roberto Mazzoli
- Structural and Functional BiochemistryLaboratory of Proteomics and Metabolic Engineering of ProkaryotesDepartment of Life Sciences and Systems BiologyUniversity of Torino Torino Italy
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Chen Y, Wu C, Fan X, Zhao X, Zhao X, Shen T, Wei D, Wang W. Engineering of Trichoderma reesei for enhanced degradation of lignocellulosic biomass by truncation of the cellulase activator ACE3. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:62. [PMID: 32266008 PMCID: PMC7110754 DOI: 10.1186/s13068-020-01701-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 03/24/2020] [Indexed: 05/07/2023]
Abstract
BACKGROUND The filamentous fungus Trichoderma reesei is a major workhorse employed to produce cellulase, which hydrolyzes lignocellulosic biomass for the production of cellulosic ethanol and bio-based products. However, the economic efficiency of biorefineries is still low. RESULTS In this study, the truncation of cellulase activator ACE3 was identified and characterized in T. reesei classical mutant NG14 and its direct descendants for the first time. We demonstrated that the truncated ACE3 is the crucial cause of cellulase hyper-production in T. reesei NG14 branch. Replacing the native ACE3 with truncated ACE3 in other T. reesei strains remarkably improves cellulase production. By truncating ACE3, we engineered a T. reesei mutant, PC-3-7-A723, capable of producing more cellulase than other strains. In a 30-L fermenter, fed-batch fermentation with PC-3-7-A723 drastically increased the maximum cellulase titer (FPase) to 102.63 IU/mL at 240 h, which constitutes a 20-30% improvement to that of the parental strain PC-3-7. CONCLUSIONS This work characterized the function of truncated ACE3 and demonstrated that analysis of classical mutants allows rational engineering of mutant strains with improved cellulase production necessary to process lignocellulosic biomass. Our rational engineering strategy might be useful for enhancing the production of other bio-based products.
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Affiliation(s)
- Yumeng Chen
- 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
- State Key Lab of Bioreactor Engineering, East China University of Science and Technology, P.O.B. 311, 130 Meilong Road, Shanghai, 200237 China
| | - Xingjia Fan
- State Key Lab of Bioreactor Engineering, East China University of Science and Technology, P.O.B. 311, 130 Meilong Road, Shanghai, 200237 China
| | - Xinqing Zhao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240 China
| | - Xihua Zhao
- College of Life Science, Jiangxi Normal University, Nanchang, 330022 China
| | - Tao Shen
- Sunson Industry Group Co, Ltd,, Beijing, China
| | - Dongzhi Wei
- 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
- 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 X, Ma B, Liu J, Chen X, Li S, Su E, Gao L, Li H. β-Glucosidase genes differentially expressed during composting. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:174. [PMID: 33088344 PMCID: PMC7570026 DOI: 10.1186/s13068-020-01813-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 10/07/2020] [Indexed: 05/06/2023]
Abstract
BACKGROUND Cellulose degradation by cellulase is brought about by complex communities of interacting microorganisms, which significantly contribute to the cycling of carbon on a global scale. β-Glucosidase (BGL) is the rate-limiting enzyme in the cellulose degradation process. Thus, analyzing the expression of genes involved in cellulose degradation and regulation of BGL gene expression during composting will improve the understanding of the cellulose degradation mechanism. Based on our previous research, we hypothesized that BGL-producing microbial communities differentially regulate the expression of glucose-tolerant BGL and non-glucose-tolerant BGL to adapt to the changes in cellulose degradation conditions. RESULTS To confirm this hypothesis, the structure and function of functional microbial communities involved in cellulose degradation were investigated by metatranscriptomics and a DNA library search of the GH1 family of BGLs involved in natural and inoculated composting. Under normal conditions, the group of non-glucose-tolerant BGL genes exhibited higher sensitivity to regulation than the glucose-tolerant BGL genes, which was suppressed during the composting process. Compared with the expression of endoglucanase and exoglucanase, the functional microbial communities exhibited a different transcriptional regulation of BGL genes during the cooling phase of natural composting. BGL-producing microbial communities upregulated the expression of glucose-tolerant BGL under carbon catabolite repression due to the increased glucose concentration, whereas the expression of non-glucose-tolerant BGL was suppressed. CONCLUSION Our results support the hypothesis that the functional microbial communities use multiple strategies of varying effectiveness to regulate the expression of BGL genes to facilitate adaptation to environmental changes.
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Affiliation(s)
- Xinyue Zhang
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Bo Ma
- School of Animal Medicine, Northeast Agricultural University, Harbin, 150030 China
- Northeastern Science Inspection Station, China Ministry of Agriculture Key Laboratory of Animal Pathogen Biology, Harbin, 150030 China
| | - Jiawen Liu
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Xiehui Chen
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Shanshan Li
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Erlie Su
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Liyuan Gao
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Hongtao Li
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
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Xue Y, Han J, Li Y, Liu J, Gan L, Long M. Promoting cellulase and hemicellulase production from Trichoderma orientalis EU7-22 by overexpression of transcription factors Xyr1 and Ace3. BIORESOURCE TECHNOLOGY 2020; 296:122355. [PMID: 31711906 DOI: 10.1016/j.biortech.2019.122355] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 10/29/2019] [Accepted: 10/30/2019] [Indexed: 05/07/2023]
Abstract
The construction of hyper-production strains of cellulase is the prerequisite for the production of biofuels or biochemicals. Trichoderma orientalis EU7-22 with complete cellulase system shows the potential for cellulase production in industrial scale. To improve the cellulase production, two crucial transcription activators Xyr1 and Ace3 were constitutively overexpressed in EU7-22 strain. Cellulase, xylanase and protein secretion were significantly improved in the recombinant strain dxyA-8 under inducing culture, which were 2.34, 0.68 and 1.06 folds higher than those of EU7-22, respectively. Moreover, the FPase and CMCase activities were up to 2.55 IU/mL and 90.38 IU/mL with glucose as carbon source, which were 2.12 and 1.95 folds higher than those of EU7-22 under inducing condition, respectively. Reducing sugar released from pretreated spartina that hydrolyzed by crude enzyme from dxyA-8 had achieved 24% improvement. Therefore, overexpression of these transcription factors effectively promotes the production of cellulase and hemicellulase of Trichoderma orientalis EU7-22.
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Affiliation(s)
- Yong Xue
- College of Energy, Xiamen University, Xiamen 361005, PR China
| | - Jiang Han
- College of Energy, Xiamen University, Xiamen 361005, PR China
| | - Yuyu Li
- College of Energy, Xiamen University, Xiamen 361005, PR China
| | - Jian Liu
- College of Energy, Xiamen University, Xiamen 361005, PR China; Xiamen Key Laboratory of High-valued Conversion Technology of Agricultural Biomass, Xiamen University, Xiamen, PR China.
| | - Lihui Gan
- College of Energy, Xiamen University, Xiamen 361005, PR China; Xiamen Key Laboratory of High-valued Conversion Technology of Agricultural Biomass, Xiamen University, Xiamen, PR China.
| | - Minnan Long
- College of Energy, Xiamen University, Xiamen 361005, PR China; Fujian Vocational College of Bioengineering, Fuzhou, PR China.
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Ramamoorthy NK, T R S, Sahadevan R. Assessment of fed-batch strategies for enhanced cellulase production from a waste lignocellulosic mixture. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.107387] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Zhang J, Chen Y, Wu C, Liu P, Wang W, Wei D. The transcription factor ACE3 controls cellulase activities and lactose metabolism via two additional regulators in the fungus Trichoderma reesei. J Biol Chem 2019; 294:18435-18450. [PMID: 31501242 PMCID: PMC6885621 DOI: 10.1074/jbc.ra119.008497] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 08/23/2019] [Indexed: 12/15/2022] Open
Abstract
Fungi of the genus Trichoderma are a rich source of enzymes, such as cellulases and hemicellulases, that can degrade lignocellulosic biomass and are therefore of interest for biotechnological approaches seeking to optimize biofuel production. The essential transcription factor ACE3 is involved in cellulase production in Trichoderma reesei; however, the mechanism by which ACE3 regulates cellulase activities is unknown. Here, we discovered that the nominal ace3 sequence in the T. reesei genome available through the Joint Genome Institute is erroneously annotated. Moreover, we identified the complete ace3 sequence, the ACE3 Zn(II)2Cys6 domain, and the ACE3 DNA-binding sites containing a 5'-CGGAN(T/A)3-3' consensus. We found that in addition to its essential role in cellulase production, ace3 is required for lactose assimilation and metabolism in T. reesei Transcriptional profiling with RNA-Seq revealed that ace3 deletion down-regulates not only the bulk of the major cellulase, hemicellulase, and related transcription factor genes, but also reduces the expression of lactose metabolism-related genes. Additionally, we demonstrate that ACE3 binds the promoters of many cellulase genes, the cellulose response transporter gene crt1, and transcription factor-encoding genes, including xyr1 We also observed that XYR1 dimerizes to facilitate cellulase production and that ACE3 interacts with XYR1. Together, these findings uncover how two essential transcriptional activators mediate cellulase gene expression in T. reesei On the basis of these observations, we propose a model of how the interactions between ACE3, Crt1, and XYR1 control cellulase expression and lactose metabolism in T. reesei.
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Affiliation(s)
- Jiajia Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Yumeng Chen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Chuan Wu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Pei Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Wei Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Dongzhi Wei
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
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Li C, Pang AP, Yang H, Lv R, Zhou Z, Wu FG, Lin F. Tracking localization and secretion of cellulase spatiotemporally and directly in living Trichoderma reesei. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:200. [PMID: 31452681 PMCID: PMC6700804 DOI: 10.1186/s13068-019-1538-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 08/04/2019] [Indexed: 05/28/2023]
Abstract
BACKGROUND Filamentous fungi secret hydrolytic enzymes like cellulase and hemicellulase outside the cells, serving as important scavengers of plant biomass in nature and workhorses in the enzyme industry. Unlike the extensive study on the mechanism of cellulase production in fungi, research on spatiotemporal distribution and secretion of cellulase in fungi is lacking, retarding the deeper understanding of the molecular mechanism behind the fungal cellulase production. RESULT Recombinant Trichoderma reesei strains RBGL, RCBH, and RCMC were successfully constructed from T. reesei RUT-C30, expressing red fluorescent protein DsRed-tagged versions of β-glucosidase (BGL), cellobiohydrolase (CBH), and endoglucanase (CMC), respectively. With the assistance of these strains, we found that all three cellulase components BGL, CBH, and CMC diffused throughout the whole fungal mycelium with major accumulation at the hyphal apexes. These enzymes located in ER, Golgi, vacuoles and cell membrane/wall, but not septum, and secreted abundantly into the culture medium. Moreover, the major secretion of CBH and CMC started more early than that of BGL. Brefeldin A (BFA) completely blocked cellulase expression and secretion in T. reesei. CONCLUSION Based on recombinant T. reesei RBGL, RCBH, and RCMC expressing DsRed-fused versions of BGL, CBH, and CMC, respectively, the distribution and secretion of cellulase production in T. reesei were first visualized directly in a dynamic way, preliminarily mapping the location and secretion of T. reesei cellulase and providing evidence for revealing the secretion pathways of cellulase in T. reesei. The obtained results suggest that cellulase excretion majorly occurs via the conventional ER-Golgi secretory pathway, and might be assisted through unconventional protein secretion pathways.
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Affiliation(s)
- Chengcheng Li
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, 37 Jinxianghe Road, Xuanwu District, Nanjing, 210096 Jiangsu China
| | - Ai-Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, 37 Jinxianghe Road, Xuanwu District, Nanjing, 210096 Jiangsu China
| | - Hang Yang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, 37 Jinxianghe Road, Xuanwu District, Nanjing, 210096 Jiangsu China
| | - Roujing Lv
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, 37 Jinxianghe Road, Xuanwu District, Nanjing, 210096 Jiangsu China
| | - Zhihua Zhou
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Fu-Gen Wu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, 37 Jinxianghe Road, Xuanwu District, Nanjing, 210096 Jiangsu China
| | - Fengming Lin
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, 37 Jinxianghe Road, Xuanwu District, Nanjing, 210096 Jiangsu China
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Chen Y, Wu C, Shen Y, Ma Y, Wei D, Wang W. N, N-dimethylformamide induces cellulase production in the filamentous fungus Trichoderma reesei. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:36. [PMID: 30820246 PMCID: PMC6380019 DOI: 10.1186/s13068-019-1375-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 02/08/2019] [Indexed: 05/04/2023]
Abstract
BACKGROUND The filamentous fungus Trichoderma reesei produces cellulase enzymes that are widely studied for lignocellulose bioconversion to biofuel. N,N-dimethylformamide (DMF) is a versatile organic solvent used in large quantities in industries. RESULTS In this study, we serendipitously found that biologically relevant concentrations of extracellular DMF-induced cellulase production in the T. reesei hyper-cellulolytic mutant Rut-C30 and wild-type strain QM6a. Next, by transcriptome analysis, we determined that plc-e encoding phospholipase C was activated by DMF and revealed that cytosolic Ca2+ plays a vital role in the response of T. reesei to DMF. Using EGTA (a putative extracellular Ca2+ chelator) and LaCl3 (a plasma membrane Ca2+ channel blocker), we demonstrated that DMF induced a cytosolic Ca2+ burst via extracellular Ca2+ and Ca2+ channels in T. reesei, and that the cytosolic Ca2+ burst induced by DMF-mediated overexpression of cellulase through calcium signaling. Deletion of crz1 confirmed that calcium signaling plays a dominant role in DMF-induced cellulase production. Additionally, 0.5-2% DMF increases the permeability of T. reesei mycelia for cellulase release. Simultaneous supplementation with 1% DMF and 10 mM Mn2+ to T. reesei Rut-C30 increased cellulase activity approximately fourfold compared to that without treatment and was also more than that observed in response to either treatment alone. CONCLUSIONS Our results reveal that DMF-induced cellulase production via calcium signaling and permeabilization. Our results also provide insight into the role of calcium signaling in enzyme production for enhanced cellulase production and the development of novel inducers of cellulase.
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Affiliation(s)
- Yumeng Chen
- State Key Lab of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237 China
| | - Chuan Wu
- State Key Lab of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237 China
| | - Yaling Shen
- State Key Lab of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O.B. 311, Shanghai, 200237 China
| | - Yushu Ma
- State Key Lab of Bioreactor Engineering, 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, 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, 130 Meilong Road, P.O.B. 311, Shanghai, 200237 China
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Zhang F, Bunterngsook B, Li JX, Zhao XQ, Champreda V, Liu CG, Bai FW. Regulation and production of lignocellulolytic enzymes from Trichoderma reesei for biofuels production. ADVANCES IN BIOENERGY 2019. [DOI: 10.1016/bs.aibe.2019.03.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Li C, Lin F, Sun W, Yuan S, Zhou Z, Wu FG, Chen Z. Constitutive hyperproduction of sorbicillinoids in Trichoderma reesei ZC121. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:291. [PMID: 30386428 PMCID: PMC6202828 DOI: 10.1186/s13068-018-1296-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 10/16/2018] [Indexed: 05/28/2023]
Abstract
BACKGROUND In addition to its outstanding cellulase production ability, Trichoderma reesei produces a wide variety of valuable secondary metabolites, the production of which has not received much attention to date. Among them, sorbicillinoids, a large group of hexaketide secondary metabolites derived from polyketides, are drawing a growing interest from researchers because they exhibit a variety of important biological functions, including anticancer, antioxidant, antiviral, and antimicrobial properties. The development of fungi strains with constitutive, hyperproduction of sorbicillinoids is thus desired for future industry application but is not well-studied. Moreover, although T. reesei has been demonstrated to produce sorbicillinoids with the corresponding gene cluster and biosynthesis pathway proposed, the underlying molecular mechanism governing sorbicillinoid biosynthesis remains unknown. RESULTS Recombinant T. reesei ZC121 was constructed from strain RUT-C30 by the insertion of the gene 12121-knockout cassette at the telomere of T. reesei chromosome IV in consideration of the off-target mutagenesis encountered during the unsuccessful deletion of gene 121121. Strain ZC121, when grown on cellulose, showed a sharp reduction of cellulase production, but yet a remarkable enhancement of sorbicillinoids production as compared to strain RUT-C30. The hyperproduction of sorbicillinoids is a constitutive process, independent of culture conditions such as carbon source, light, pH, and temperature. To the best of our knowledge, strain ZC121 displays record sorbicillinoid production levels when grown on both glucose and cellulose. Sorbicillinol and bisvertinolone are the two major sorbicillinoid compounds produced. ZC121 displayed a different morphology and markedly reduced sporulation compared to RUT-C30 but had a similar growth rate and biomass. Transcriptome analysis showed that most genes involved in cellulase production were downregulated significantly in ZC121 grown on cellulose, whereas remarkably all genes in the sorbicillinoid gene cluster were upregulated on both cellulose and glucose. CONCLUSION A constitutive sorbicillinoid-hyperproduction strain T. reesei ZC121 was obtained by off-target mutagenesis, displaying an overwhelming shift from cellulase production to sorbicillinoid production on cellulose, leading to a record for sorbicillinoid production. For the first time, T. reesei degraded cellulose to produce platform chemical compounds other than protein in high yield. We propose that the off-target mutagenesis occurring at the telomere region might cause chromosome remodeling and subsequently alter the cell structure and the global gene expression pattern of strain ZC121, as shown by phenotype profiling and comparative transcriptome analysis of ZC121. Overall, T. reesei ZC121 holds great promise for the industrial production of sorbicillinoids and serves as a good model to explore the regulation mechanism of sorbicillinoids' biosynthesis.
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Affiliation(s)
- Chengcheng Li
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 China
| | - Fengming Lin
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 China
- Nanjing, China
| | - Wei Sun
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 China
| | - Shaoxun Yuan
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 China
| | - Zhihua Zhou
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Fu-Gen Wu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 China
| | - Zhan Chen
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, MI 48109 USA
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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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Xia Y, Yang L, Xia L. Preparation of a novel soluble inducer by cellobiase-release microcapsules and its application in cellulase production. J Biotechnol 2018; 279:22-26. [DOI: 10.1016/j.jbiotec.2018.05.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 04/03/2018] [Accepted: 05/02/2018] [Indexed: 01/05/2023]
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Xia Y, Yang L, Xia L. High-level production of a fungal β-glucosidase with application potentials in the cost-effective production of Trichoderma reesei cellulase. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.03.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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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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Wang L, Zheng F, Zhang W, Zhong Y, Chen G, Meng X, Liu W. A copper-controlled RNA interference system for reversible silencing of target genes in Trichoderma reesei. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:33. [PMID: 29449881 PMCID: PMC5806297 DOI: 10.1186/s13068-018-1038-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 02/01/2018] [Indexed: 05/25/2023]
Abstract
BACKGROUND Trichoderma reesei is a primary lignocellulosic enzyme producer in industry. However, the mechanisms underlying cellulase synthesis as well as other physiological processes are insufficiently understood partly due to the sophisticated process for its genetic manipulation. Target gene knockdown by RNA interference (RNAi) is a powerful tool for genetic research and biotechnology in eukaryotes including filamentous fungi. Previously reported RNAi system in T. reesei was either uncontrollable or only applicable in certain nutrition state. RESULTS In the present study, we incorporated the copper-responsive tcu1 promoter into an RNAi-mediated silencing system to develop a controllable RNAi-mediated silencing system in T. reesei. As the proof-of-concept, a prototrophic pyr4 gene, highly expressed cel7a and xyr1 genes induced by Avicel and a fab1 gene, whose knockout has proved to be intractable, were successfully knocked down in the absence of copper when the respective RNAi fragment was expressed. Importantly, the phenotype of RNAi strains was shown to be reversed easily to mimic the complementation for excluding any unwanted effects resulted from the random integration of the hpRNA cassette by adding copper in the media. Thus, this controllable RNAi-mediated silencing system can be turned on and turned off only depending on the absence and presence of copper ions in the media, respectively, and not on the nutritional states. CONCLUSIONS The copper-controlled RNA interference system represents an effective tool for reversible silencing of target genes in T. reesei. This reported strategy to conditionally knock down or turn off genes will contribute to our understanding of T. reesei gene functions, especially those that are difficult to be knocked out due to various reasons. In addition, this simple and cost-effective method holds great potential for the application in synthetic biology and genetic engineering of T. reesei.
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Affiliation(s)
- Lei Wang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No.27 Shanda South Road, Jinan, 250100 Shandong People’s Republic of China
| | - Fanglin Zheng
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No.27 Shanda South Road, Jinan, 250100 Shandong People’s Republic of China
| | - Weixin Zhang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No.27 Shanda South Road, Jinan, 250100 Shandong People’s Republic of China
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No.27 Shanda South Road, Jinan, 250100 Shandong People’s Republic of China
| | - Guanjun Chen
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No.27 Shanda South Road, Jinan, 250100 Shandong People’s Republic of China
| | - Xiangfeng Meng
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No.27 Shanda South Road, Jinan, 250100 Shandong People’s Republic of China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No.27 Shanda South Road, Jinan, 250100 Shandong People’s Republic of China
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