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Liu X, Wang Y, Zhang R, Gao Y, Chen H, Dong S, Hu X. Insights into the transcriptomic mechanism and characterization of endoglucanases from Aspergillus terreus in cellulose degradation. Int J Biol Macromol 2024; 263:130340. [PMID: 38387642 DOI: 10.1016/j.ijbiomac.2024.130340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 02/12/2024] [Accepted: 02/19/2024] [Indexed: 02/24/2024]
Abstract
Filamentous fungi are the main industrial source of cellulases which are important in the process of converting cellulose to fermentable sugars. In this study, transcriptome analysis was conducted on Aspergillus terreus NEAU-7 cultivated using corn stover and glucose as carbon sources. Four putative endoglucanases (EG5A, EG7A, EG12A, and EG12C) from A. terreus NEAU-7 were efficiently expressed in Pichia pastoris. Among them, EG7A exhibited the highest enzyme activity (75.17 U/mg) with an optimal temperature of 40 °C and pH 5.0. EG5A and EG12A displayed specific activities of 19.92 U/mg and 14.62 U/mg, respectively, at 50 °C. EG12C showed acidophilic characteristics with an optimal pH of 3.0 and a specific activity of 12.21 U/mg at 40 °C. With CMC-Na as the substrate, the Km value of EG5A, EG7A, EG12A or, EG12C was, 11.08 ± 0.87 mg/mL, 6.82 ± 0.74 mg/mL, 7.26 ± 0.64 mg/mL, and 9.88 ± 0.86 mg/mL, with Vmax values of 1258.23 ± 51.62 μmol∙min-1∙mg-1, 842.65 ± 41.53 μmol∙min-1∙mg-1, 499.38 ± 20.42 μmol∙min-1∙mg-1, and 681.41 ± 30.08 μmol∙min-1∙mg-1, respectively. The co-treatment of EG7A with the commercial cellulase increased the yield of reducing sugar by 155.77 % (filter paper) and 130.49 % (corn stover). Molecular docking assay showed the interaction energy of EG7A with cellotetraose at -10.50 kcal/mol, surpassing EG12A (-10.43 kcal/mol), EG12C (-10.28 kcal/mol), and EG5A (-9.00 kcal/mol). Root Mean Square Deviation (RMSD) and Solvent Accessible Surface Area (SASA) values revealed that the presence of cellotetraose stabilized the molecular dynamics simulation of the cellotetraose-protein complex over a 100 ns time scale. This study provides valuable insights for developing recombinant enzymes and biomass degradation technologies.
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Affiliation(s)
- Xin Liu
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Yanbo Wang
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Rui Zhang
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Yunfei Gao
- Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China
| | - Heshu Chen
- Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China
| | | | - Xiaomei Hu
- College of Life Science, Northeast Agricultural University, Harbin 150030, China.
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2
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Nogueira KMV, Mendes V, Kamath KS, Cheruku A, Oshiquiri LH, de Paula RG, Carraro C, Pedersoli WR, Pereira LMS, Vieira LC, Steindorff AS, Amirkhani A, McKay MJ, Nevalainen H, Molloy MP, Silva RN. Proteome profiling of enriched membrane-associated proteins unraveled a novel sophorose and cello-oligosaccharide transporter in Trichoderma reesei. Microb Cell Fact 2024; 23:22. [PMID: 38229067 DOI: 10.1186/s12934-023-02279-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 12/18/2023] [Indexed: 01/18/2024] Open
Abstract
BACKGROUND Trichoderma reesei is an organism extensively used in the bioethanol industry, owing to its capability to produce enzymes capable of breaking down holocellulose into simple sugars. The uptake of carbohydrates generated from cellulose breakdown is crucial to induce the signaling cascade that triggers cellulase production. However, the sugar transporters involved in this process in T. reesei remain poorly identified and characterized. RESULTS To address this gap, this study used temporal membrane proteomics analysis to identify five known and nine putative sugar transporters that may be involved in cellulose degradation by T. reesei. Docking analysis pointed out potential ligands for the putative sugar transporter Tr44175. Further functional validation of this transporter was carried out in Saccharomyces cerevisiae. The results showed that Tr44175 transports a variety of sugar molecules, including cellobiose, cellotriose, cellotetraose, and sophorose. CONCLUSION This study has unveiled a transporter Tr44175 capable of transporting cellobiose, cellotriose, cellotetraose, and sophorose. Our study represents the first inventory of T. reesei sugar transportome once exposed to cellulose, offering promising potential targets for strain engineering in the context of bioethanol production.
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Affiliation(s)
- Karoline Maria Vieira Nogueira
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Vanessa Mendes
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Karthik Shantharam Kamath
- Department of Natural Sciences, Macquarie University, Sydney, NSW, Australia
- Australian Proteome Analysis Facility, Macquarie University, Sydney, NSW, Australia
| | - Anusha Cheruku
- Australian Proteome Analysis Facility, Macquarie University, Sydney, NSW, Australia
| | - Letícia Harumi Oshiquiri
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Renato Graciano de Paula
- Department of Physiological Sciences, Health Sciences Centre, Federal University of Espirito Santo, Vitoria, ES, 29047-105, Brazil
| | - Claudia Carraro
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Wellington Ramos Pedersoli
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Lucas Matheus Soares Pereira
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Luiz Carlos Vieira
- Department of Molecular and Cell Biology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Andrei Stecca Steindorff
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Ardeshir Amirkhani
- Australian Proteome Analysis Facility, Macquarie University, Sydney, NSW, Australia
| | - Matthew J McKay
- Australian Proteome Analysis Facility, Macquarie University, Sydney, NSW, Australia
| | - Helena Nevalainen
- Department of Natural Sciences, Macquarie University, Sydney, NSW, Australia
| | - Mark P Molloy
- Australian Proteome Analysis Facility, Macquarie University, Sydney, NSW, Australia
| | - Roberto N Silva
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto, SP, Brazil.
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3
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Li Z, Cai C, Huo X, Li X, Lin Z. Sucrose-nonfermenting 1 kinase activates histone acetylase GCN5 to promote cellulase production in Trichoderma. Appl Microbiol Biotechnol 2023:10.1007/s00253-023-12617-x. [PMID: 37318636 DOI: 10.1007/s00253-023-12617-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 05/18/2023] [Accepted: 05/24/2023] [Indexed: 06/16/2023]
Abstract
Trichoderma serves as the primary producer of cellulases and hemicellulases in industrial settings as it readily secretes a variety of cellulolytic enzymes. The protein kinase SNF1 (sucrose-nonfermenting 1) can enable cells to adapt to changes in carbon metabolism by phosphorylating key rate-limiting enzymes involved in the maintenance of energy homeostasis and carbon metabolism within cells. Histone acetylation is an important epigenetic regulatory mechanism that influences physiological and biochemical processes. GCN5 is a representative histone acetylase involved in promoter chromatin remodeling and associated transcriptional activation. Here, the TvSNF1 and TvGCN5 genes were identified in Trichoderma viride Tv-1511, which exhibits promising activity with respect to its ability to produce cellulolytic enzymes for biological transformation. The SNF1-mediated activation of the histone acetyltransferase GCN5 was herein found to promote cellulase production in T. viride Tv-1511 via facilitating changes in histone acetylation. These results demonstrated that cellulolytic enzyme activity and the expression of genes encoding cellulases and transcriptional activators were clearly enhanced in T. viride Tv-1511 mutants in which TvSNF1 and TvGCN5 were overexpressed, with concomitant changes in histone H3 acetylation levels associated with these genes. GCN5 was also found to be directly recruited to promoter regions to alter histone acetylation, while SNF1 functioned upstream as a transcriptional activator that promotes GCN5 upregulation at the mRNA and protein levels in the context of cellulase induction in T. viride Tv-1511. These findings underscore the important role that this SNF1-GCN5 cascade plays in regulating cellulase production in T. viride Tv-1511 by promoting altered histone acetylation, offering a theoretical basis for the optimization of T. viride in the context of industrial cellulolytic enzyme production. KEY POINTS: • SNF1 kinase and GCN5 acetylase promoted cellulase production in Trichoderma by increasing the expression of genes encoding cellulases and transcriptional activators • SNF1 and GCN5 promoted cellulase production by driving H3ac modifications, and GCN5 directly band to the promoter regions to catalyze distinct H3ac modifications • SNF1 acts upstream of GCN5 as a transcriptional activator in the cellulase production of Trichoderma.
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Affiliation(s)
- Zhe Li
- Biology Institute, Qilu University of Technology, Jinan, 250014, China.
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 10085, China.
| | - Chunjing Cai
- Biology Institute, Qilu University of Technology, Jinan, 250014, China
| | - Xuexue Huo
- Biology Institute, Qilu University of Technology, Jinan, 250014, China
| | - Xuan Li
- Biology Institute, Qilu University of Technology, Jinan, 250014, China
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 10085, China
| | - Zhong Lin
- Faculty of Chemistry and Environmental Science, Guangdong Ocean University, Zhanjiang, 524088, China.
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Arai T, Ichinose S, Shibata N, Kakeshita H, Kodama H, Igarashi K, Takimura Y. Inducer-free cellulase production system based on the constitutive expression of mutated XYR1 and ACE3 in the industrial fungus Trichoderma reesei. Sci Rep 2022; 12:19445. [PMID: 36376415 PMCID: PMC9663580 DOI: 10.1038/s41598-022-23815-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 11/07/2022] [Indexed: 11/16/2022] Open
Abstract
Trichoderma reesei is a widely used host for producing cellulase and hemicellulase cocktails for lignocellulosic biomass degradation. Here, we report a genetic modification strategy for industrial T. reesei that enables enzyme production using simple glucose without inducers, such as cellulose, lactose and sophorose. Previously, the mutated XYR1V821F or XYR1A824V was known to induce xylanase and cellulase using only glucose as a carbon source, but its enzyme composition was biased toward xylanases, and its performance was insufficient to degrade lignocellulose efficiently. Therefore, we examined combinations of mutated XYR1V821F and constitutively expressed CRT1, BGLR, VIB1, ACE2, or ACE3, known as cellulase regulators and essential factors for cellulase expression to the T. reesei E1AB1 strain that has been highly mutagenized for improving enzyme productivity and expressing a ß-glucosidase for high enzyme performance. The results showed that expression of ACE3 to the mutated XYR1V821F expressing strain promoted cellulase expression. Furthermore, co-expression of these two transcription factors also resulted in increased productivity, with enzyme productivity 1.5-fold higher than with the conventional single expression of mutated XYR1V821F. Additionally, that productivity was 5.5-fold higher compared to productivity with an enhanced single expression of ACE3. Moreover, although the DNA-binding domain of ACE3 had been considered essential for inducer-free cellulase production, we found that ACE3 with a partially truncated DNA-binding domain was more effective in cellulase production when co-expressed with a mutated XYR1V821F. This study demonstrates that co-expression of the two transcription factors, the mutated XYR1V821F or XYR1A824V and ACE3, resulted in optimized enzyme composition and increased productivity.
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Affiliation(s)
- Toshiharu Arai
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
| | - Sakurako Ichinose
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
| | - Nozomu Shibata
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
| | - Hiroshi Kakeshita
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan.
| | - Hiroshi Kodama
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
| | - Kazuaki Igarashi
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
| | - Yasushi Takimura
- Biological Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, 640‑8580, Japan
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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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6
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Li N, Zeng Y, Chen Y, Shen Y, Wang W. Induction of cellulase production by Sr 2+ in Trichoderma reesei via calcium signaling transduction. BIORESOUR BIOPROCESS 2022; 9:96. [PMID: 38647894 PMCID: PMC10992071 DOI: 10.1186/s40643-022-00587-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 08/28/2022] [Indexed: 11/10/2022] Open
Abstract
Trichoderma reesei RUT-C30 is a well-known high-yielding cellulase-producing fungal strain that converts lignocellulose into cellulosic sugar for resource regeneration. Calcium is a ubiquitous secondary messenger that regulates growth and cellulase production in T. reesei. We serendipitously found that adding Sr2+ to the medium significantly increased cellulase activity in the T. reesei RUT-C30 strain and upregulated the expression of cellulase-related genes. Further studies showed that Sr2+ supplementation increased the cytosolic calcium concentration and activated the calcium-responsive signal transduction pathway of Ca2+-calcineurin-responsive zinc finger transcription factor 1 (CRZ1). Using the plasma membrane Ca2+ channel blocker, LaCl3, we demonstrated that Sr2+ induces cellulase production via the calcium signaling pathway. Supplementation with the corresponding concentrations of Sr2+ also inhibited colony growth. Sr2+ supplementation led to an increase in intracellular reactive oxygen species (ROS) and upregulated the transcriptional levels of intracellular superoxide dismutase (sod1) and catalase (cat1). We further demonstrated that ROS content was detrimental to cellulase production, which was alleviated by the ROS scavenger N-acetyl cysteine (NAC). This study demonstrated for the first time that Sr2+ supplementation stimulates cellulase production and upregulates cellulase genes via the calcium signaling transduction pathway. Sr2+ leads to an increase in intracellular ROS, which is detrimental to cellulase production and can be alleviated by the ROS scavenger NAC. Our results provide insights into the mechanistic study of cellulase synthesis and the discovery of novel inducers of cellulase.
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Affiliation(s)
- Ni Li
- The State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Yi Zeng
- The State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Yumeng Chen
- The State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Yaling Shen
- The State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Wei Wang
- The State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China.
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7
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Pedersoli WR, de Paula RG, Antoniêto ACC, Carraro CB, Taveira IC, Maués DB, Martins MP, Ribeiro LFC, Damasio ARDL, Silva-Rocha R, Filho AR, Silva RN. Analysis of the phosphorylome of trichoderma reesei cultivated on sugarcane bagasse suggests post-translational regulation of the secreted glycosyl hydrolase Cel7A. ACTA ACUST UNITED AC 2021; 31:e00652. [PMID: 34258241 PMCID: PMC8254082 DOI: 10.1016/j.btre.2021.e00652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 05/05/2021] [Accepted: 06/16/2021] [Indexed: 11/27/2022]
Abstract
Phosphorylome of Trichoderma reesei reveals phosphosites in some glycosyl hydrolases. Phosphoserine and phosphothreonine is the major phosphosites identified. Protein Kinase C is the most frequently predicted kinase in phosphorylome. The cellulase Cel7A activity is affected by dephosphorylation.
Trichoderma reesei is one of the major producers of holocellulases. It is known that in T. reesei, protein production patterns can change in a carbon source-dependent manner. Here, we performed a phosphorylome analysis of T. reesei grown in the presence of sugarcane bagasse and glucose as carbon source. In presence of sugarcane bagasse, a total of 114 phosphorylated proteins were identified. Phosphoserine and phosphothreonine corresponded to 89.6% of the phosphosites and 10.4% were related to phosphotyrosine. Among the identified proteins, 65% were singly phosphorylated, 19% were doubly phosphorylated, 12% were triply phosphorylated, and 4% displayed even higher phosphorylation. Seventy-five kinases were predicted to phosphorylate the sites identified in this work, and the most frequently predicted serine/threonine kinase was PKC1. Among phosphorylated proteins, four glycosyl hydrolases were predicted to be secreted. Interestingly, Cel7A activity, the most secreted protein, was reduced to approximately 60% after in vitro dephosphorylation, suggesting that phosphorylation might alter Cel7A structure, substrate affinity, and targeting of the substrate to its carbohydrate-binding domain. These results suggest a novel post-translational regulation of Cel7A.
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Affiliation(s)
- Wellington Ramos Pedersoli
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
| | - Renato Graciano de Paula
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil.,Department of Physiological Sciences, Health Sciences Centre, Federal University of Espirito Santo, Vitória, ES, 29047-105, Brazil
| | - Amanda Cristina Campos Antoniêto
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
| | - Cláudia Batista Carraro
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
| | - Iasmin Cartaxo Taveira
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
| | - David Batista Maués
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
| | - Maíra Pompeu Martins
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
| | - Liliane Fraga Costa Ribeiro
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
| | - André Ricardo de Lima Damasio
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, SP, 13083-970, Brazil
| | - Rafael Silva-Rocha
- Systems and Synthetic Biology Laboratory, Department of Cell and Molecular Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, 14049-900, Brazil
| | - Antônio Rossi Filho
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
| | - Roberto N Silva
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
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8
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Sukumaran RK, Christopher M, Kooloth-Valappil P, Sreeja-Raju A, Mathew RM, Sankar M, Puthiyamadam A, Adarsh VP, Aswathi A, Rebinro V, Abraham A, Pandey A. Addressing challenges in production of cellulases for biomass hydrolysis: Targeted interventions into the genetics of cellulase producing fungi. BIORESOURCE TECHNOLOGY 2021; 329:124746. [PMID: 33610429 DOI: 10.1016/j.biortech.2021.124746] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 06/12/2023]
Abstract
Lignocellulosic materials are the favoured feedstock for biorefineries due to their abundant availability and non-completion with food. Biobased technologies for refining these materials are limited mainly by the cost of biomass hydrolyzing enzymes, typically sourced from filamentous fungi. Therefore, considerable efforts have been directed at improving the quantity and quality of secreted lignocellulose degrading enzymes from fungi in order to attain overall economic viability. Process improvements and media engineering probably have reached their thresholds and further production enhancements require modifying the fungal metabolism to improve production and secretion of these enzymes. This review focusses on the types and mechanisms of action of known fungal biomass degrading enzymes, our current understanding of the genetic control exerted on their expression, and possible routes for intervention, especially on modulating catabolite repression, transcriptional regulators, signal transduction, secretion pathways etc., in order to improve enzyme productivity, activity and stability.
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Affiliation(s)
- Rajeev K Sukumaran
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India.
| | - Meera Christopher
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Prajeesh Kooloth-Valappil
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - AthiraRaj Sreeja-Raju
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Reshma M Mathew
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Meena Sankar
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Anoop Puthiyamadam
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
| | - Velayudhanpillai-Prasannakumari Adarsh
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
| | - Aswathi Aswathi
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Valan Rebinro
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
| | - Amith Abraham
- Department of Chemical Engineering, Hanyang University, Seoul, Republic of Korea
| | - Ashok Pandey
- Centre for Innovation and Translational Research, CSIR-Indian Institute of Toxicology Research, Lucknow, India
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Lopes DCB, Carraro CB, Silva RN, de Paula RG. Molecular Characterization of Xyloglucanase cel74a from Trichoderma reesei. Int J Mol Sci 2021; 22:ijms22094545. [PMID: 33925273 PMCID: PMC8123685 DOI: 10.3390/ijms22094545] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The filamentous fungus Trichoderma reesei is used on an industrial scale to produce enzymes of biotechnological interest. This fungus has a complex cellulolytic system involved in the degradation of lignocellulosic biomass. However, several aspects related to the regulation of the expression of holocellulolytic genes and the production of cellulases by this fungus are still understood. METHODS Here, we constructed a null mutant strain for the xyloglucanase cel74a gene and performed the characterization of the Δcel74a strain to evaluate the genetic regulation of the holocellulases during sugarcane bagasse (SCB) cultivation. RESULTS Our results demonstrate that the deletion of xyloglucanase cel74a may impact the regulation of holocellulase expression during SCB cultivation. The expression of cellulases cel7a, cel7b, and cel6a was reduced in Δcel74a strain, while the hemicellulases xyn1 and xyn2 were increased in the presence of SCB. The cel74a mutation also affected the xyloglucan hydrolysis patterns. In addition, CEL74A activity was modulated in the presence of calcium, suggesting that this ion may be required for efficient degradation of xyloglucan. CONCLUSIONS CEL74A affects the regulation of holocellulolytic genes and the efficient degradation of SCB in T. reesei. This data makes a significant contribution to our understanding of the carbon utilization of fungal strains as a whole.
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Affiliation(s)
- Douglas Christian Borges Lopes
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto 14049-900, SP, Brazil; (D.C.B.L.); (C.B.C.); (R.G.d.P.)
| | - Cláudia Batista Carraro
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto 14049-900, SP, Brazil; (D.C.B.L.); (C.B.C.); (R.G.d.P.)
| | - Roberto Nascimento Silva
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto 14049-900, SP, Brazil; (D.C.B.L.); (C.B.C.); (R.G.d.P.)
- Correspondence:
| | - Renato Graciano de Paula
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirao Preto Medical School (FMRP), University of Sao Paulo, Ribeirao Preto 14049-900, SP, Brazil; (D.C.B.L.); (C.B.C.); (R.G.d.P.)
- Department of Physiological Sciences, Health Sciences Centre, Federal University of Espirito Santo, Vitoria 29047-105, ES, Brazil
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10
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Peng M, Khosravi C, Lubbers RJM, Kun RS, Aguilar Pontes MV, Battaglia E, Chen C, Dalhuijsen S, Daly P, Lipzen A, Ng V, Yan J, Wang M, Visser J, Grigoriev IV, Mäkelä MR, de Vries RP. CreA-mediated repression of gene expression occurs at low monosaccharide levels during fungal plant biomass conversion in a time and substrate dependent manner. ACTA ACUST UNITED AC 2021; 7:100050. [PMID: 33778219 PMCID: PMC7985698 DOI: 10.1016/j.tcsw.2021.100050] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 02/28/2021] [Accepted: 02/28/2021] [Indexed: 12/15/2022]
Abstract
Carbon catabolite repression enables fungi to utilize the most favourable carbon source in the environment, and is mediated by a key regulator, CreA, in most fungi. CreA-mediated regulation has mainly been studied at high monosaccharide concentrations, an uncommon situation in most natural biotopes. In nature, many fungi rely on plant biomass as their major carbon source by producing enzymes to degrade plant cell wall polysaccharides into metabolizable sugars. To determine the role of CreA when fungi grow in more natural conditions and in particular with respect to degradation and conversion of plant cell walls, we compared transcriptomes of a creA deletion and reference strain of the ascomycete Aspergillus niger during growth on sugar beet pulp and wheat bran. Transcriptomics, extracellular sugar concentrations and growth profiling of A. niger on a variety of carbon sources, revealed that also under conditions with low concentrations of free monosaccharides, CreA has a major effect on gene expression in a strong time and substrate composition dependent manner. In addition, we compared the CreA regulon from five fungi during their growth on crude plant biomass or cellulose. It showed that CreA commonly regulated genes related to carbon metabolism, sugar transport and plant cell wall degrading enzymes across different species. We therefore conclude that CreA has a crucial role for fungi also in adapting to low sugar concentrations as occurring in their natural biotopes, which is supported by the presence of CreA orthologs in nearly all fungi.
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Affiliation(s)
- Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Claire Khosravi
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Ronnie J M Lubbers
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Roland S Kun
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Maria Victoria Aguilar Pontes
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Evy Battaglia
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Cindy Chen
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States
| | - Sacha Dalhuijsen
- Microbiology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Paul Daly
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Anna Lipzen
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States
| | - Vivian Ng
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States
| | - Juying Yan
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States
| | - Mei Wang
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States
| | - Jaap Visser
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Igor V Grigoriev
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States.,Department of Plant and Microbial Biology, University of California Berkeley, 111 Koshland Hall, Berkeley, CA 94720, USA
| | - Miia R Mäkelä
- Department of Microbiology, University of Helsinki, Viikinkaari 9, Helsinki, Finland
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
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11
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Karuppiah V, Zhixiang L, Liu H, Vallikkannu M, Chen J. Co-culture of Vel1-overexpressed Trichoderma asperellum and Bacillus amyloliquefaciens: An eco-friendly strategy to hydrolyze the lignocellulose biomass in soil to enrich the soil fertility, plant growth and disease resistance. Microb Cell Fact 2021; 20:57. [PMID: 33653343 PMCID: PMC7927390 DOI: 10.1186/s12934-021-01540-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 02/10/2021] [Indexed: 11/17/2022] Open
Abstract
Background Retention of agricultural bio-mass residues without proper treatment could affect the subsequent plant growth. In the present investigation, the co-cultivation of genetically engineered T. asperellum and B. amyloliquefaciens has been employed for multiple benefits including the enrichment of lignocellulose biodegradation, plant growth, defense potential and disease resistance. Results The Vel1 gene predominantly regulates the secondary metabolites, sexual and asexual development as well as cellulases and polysaccharide hydrolases productions. Overexpression mutant of the Trichoderma asperellum Vel1 locus (TA OE-Vel1) enhanced the activity of FPAase, CMCase, PNPCase, PNPGase, xylanase I, and xylanase II through the regulation of transcription regulating factors and the activation of cellulase and xylanase encoding genes. Further, these genes were induced upon co-cultivation with Bacillus amyloliquefaciens (BA). The co-culture of TA OE-Vel1 + BA produced the best composition of enzymes and the highest biomass hydrolysis yield of 89.56 ± 0.61%. The co-culture of TA OE-Vel1 + BA increased the corn stover degradation by the secretion of cellulolytic enzymes and maintained the C/N ratio of the corn stover amended soil. Moreover, the TA OE-Vel1 + BA increased the maize plant growth, expression of defense gene and disease resistance against Fusarium verticillioides and Cohilohorus herostrophus. Conclusion The co-cultivation of genetically engineered T. asperellum and B. amyloliquefaciens could be utilized as a profound and meaningful technique for the retention of agro residues and subsequent plant growth.
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Affiliation(s)
- Valliappan Karuppiah
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800, Dongchuan Road, Minhang, Shanghai, 200240, PR China.,The State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, PR China
| | - Lu Zhixiang
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800, Dongchuan Road, Minhang, Shanghai, 200240, PR China.,The State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, PR China
| | - Hongyi Liu
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800, Dongchuan Road, Minhang, Shanghai, 200240, PR China.,The State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, PR China
| | - Murugappan Vallikkannu
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800, Dongchuan Road, Minhang, Shanghai, 200240, PR China.,The State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, PR China
| | - Jie Chen
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800, Dongchuan Road, Minhang, Shanghai, 200240, PR China. .,The State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, PR China.
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12
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Effect of Oligosaccharide Degree of Polymerization on the Induction of Xylan-Degrading Enzymes by Fusarium oxysporum f. sp. Lycopersici. Molecules 2020; 25:molecules25245849. [PMID: 33322262 PMCID: PMC7764074 DOI: 10.3390/molecules25245849] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/08/2020] [Accepted: 12/09/2020] [Indexed: 01/15/2023] Open
Abstract
Xylan is one of the most abundant carbohydrates on Earth. Complete degradation of xylan is achieved by the collaborative action of endo-β-1,4-xylanases and β-d-xylosidases and a number of accessories enzymes. In filamentous fungi, the xylanolytic system is controlled through induction and repression. However, the exact mechanism remains unclear. Substrates containing xylan promote the induction of xylanases, which release xylooligosaccharides. These, in turn, induce expression of xylanase-encoding genes. Here, we aimed to determine which xylan degradation products acted as inducers, and whether the size of the released oligomer correlated with its induction strength. To this end, we compared xylanase production by different inducers, such as sophorose, lactose, cellooligosaccharides, and xylooligosaccharides in Fusarium oxysporum f. sp. lycopersici. Results indicate that xylooligosaccharides are more effective than other substrates at inducing endoxylanase and β-xylosidases. Moreover, we report a correlation between the degree of xylooligosaccharide polymerization and induction efficiency of each enzyme. Specifically, xylotetraose is the best inducer of endoxylanase, xylohexaose of extracellular β-xylosidase, and xylobiose of cell-bound β-xylosidase.
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13
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Pirayre A, Duval L, Blugeon C, Firmo C, Perrin S, Jourdier E, Margeot A, Bidard F. Glucose-lactose mixture feeds in industry-like conditions: a gene regulatory network analysis on the hyperproducing Trichoderma reesei strain Rut-C30. BMC Genomics 2020; 21:885. [PMID: 33302864 PMCID: PMC7731781 DOI: 10.1186/s12864-020-07281-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 11/25/2020] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The degradation of cellulose and hemicellulose molecules into simpler sugars such as glucose is part of the second generation biofuel production process. Hydrolysis of lignocellulosic substrates is usually performed by enzymes produced and secreted by the fungus Trichoderma reesei. Studies identifying transcription factors involved in the regulation of cellulase production have been conducted but no overview of the whole regulation network is available. A transcriptomic approach with mixtures of glucose and lactose, used as a substrate for cellulase induction, was used to help us decipher missing parts in the network of T. reesei Rut-C30. RESULTS Experimental results on the Rut-C30 hyperproducing strain confirmed the impact of sugar mixtures on the enzymatic cocktail composition. The transcriptomic study shows a temporal regulation of the main transcription factors and a lactose concentration impact on the transcriptional profile. A gene regulatory network built using BRANE Cut software reveals three sub-networks related to i) a positive correlation between lactose concentration and cellulase production, ii) a particular dependence of the lactose onto the β-glucosidase regulation and iii) a negative regulation of the development process and growth. CONCLUSIONS This work is the first investigating a transcriptomic study regarding the effects of pure and mixed carbon sources in a fed-batch mode. Our study expose a co-orchestration of xyr1, clr2 and ace3 for cellulase and hemicellulase induction and production, a fine regulation of the β-glucosidase and a decrease of growth in favor of cellulase production. These conclusions provide us with potential targets for further genetic engineering leading to better cellulase-producing strains in industry-like conditions.
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Affiliation(s)
- Aurélie Pirayre
- IFP Energies nouvelles, 1 et 4 avenue de Bois-Préau, Rueil-Malmaison, 92852, France.
| | - Laurent Duval
- IFP Energies nouvelles, 1 et 4 avenue de Bois-Préau, Rueil-Malmaison, 92852, France
- Laboratoire d'Informatique Gaspard-Monge (LIGM), ESIEE Paris, Université-Gustave Eiffel, Marne-la-Vallée, F-77454, France
| | - Corinne Blugeon
- Genomic facility, Institut de Biologie de l'ENS (IBENS), Département de biologie, École normale supérieure, CNRS, INSERM, Université PSL, Paris, 75005, France
| | - Cyril Firmo
- Genomic facility, Institut de Biologie de l'ENS (IBENS), Département de biologie, École normale supérieure, CNRS, INSERM, Université PSL, Paris, 75005, France
| | - Sandrine Perrin
- Genomic facility, Institut de Biologie de l'ENS (IBENS), Département de biologie, École normale supérieure, CNRS, INSERM, Université PSL, Paris, 75005, France
| | - Etienne Jourdier
- IFP Energies nouvelles, 1 et 4 avenue de Bois-Préau, Rueil-Malmaison, 92852, France
| | - Antoine Margeot
- IFP Energies nouvelles, 1 et 4 avenue de Bois-Préau, Rueil-Malmaison, 92852, France
| | - Frédérique Bidard
- IFP Energies nouvelles, 1 et 4 avenue de Bois-Préau, Rueil-Malmaison, 92852, France
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14
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Nait M'Barek H, Arif S, Taidi B, Hajjaj H. Consolidated bioethanol production from olive mill waste: Wood-decay fungi from central Morocco as promising decomposition and fermentation biocatalysts. ACTA ACUST UNITED AC 2020; 28:e00541. [PMID: 33102160 PMCID: PMC7578684 DOI: 10.1016/j.btre.2020.e00541] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 10/05/2020] [Accepted: 10/09/2020] [Indexed: 11/24/2022]
Abstract
First report on lignocellulolytic activity and diversity of fungi from central Morocco. Olive Mill Waste (OMW) is a suitable biomass for local biorefinery in Meknes region. Fusaria isolates produce high and diversified lignocellulases using Consolidated Bioprocess. Fusarium oxysporum (76) achieves 2.47 g.L−1 bioethanol production and 0.84 g.g−1 yield. Bioethanol is maximally produced during the oxygen-limiting phase.
Meknes region is a Moroccan olive-processing area generating high amounts of non-valorized Olive Mill Waste (OMW). Fungi are natural decomposers producing varied enzyme classes and effectively contributing to the carbon cycle. However, structural complexity of biomass and modest performances of wild fungi are major limits for local biorefineries. The objective of current research is to assess the ability of local fungi for bioethanol production from OMW using Consolidated Bioprocessing (CBP). This is done by characterizing lignocellulolytic potential of six wood-decay and compost-inhabiting ascomycetes and selecting potent fermentation biocatalysts. High and diversified activities were expressed by Fusarium solani and Fusarium oxysporum: 9.36 IU. mL−1 and 2.88 IU. mL−1 total cellulase activity, 0.54 IU. mL−1 and 0.57 IU. mL−1 laccase activity, respectively, and 8.43 IU. mL−1 lignin peroxidase activity for the latter. F. oxysporum had maximum bioethanol production and yield of 2.47 g.L-1 and 0.84 g.g−1, respectively, qualifying it as an important bio-agent for single-pot local biorefinery.
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Affiliation(s)
- Hasna Nait M'Barek
- Faculty of Sciences of Meknes, Laboratory of Plant Biotechnology and Molecular Biology, BP 11201, Zitoune Meknes City, Morocco.,Cluster of Competency «Agri-food, Safety and Security» IUC VLIR-UOS, Moulay Ismail University, Marjane 2, BP 298, Meknes City, Morocco
| | - Soukaina Arif
- Faculty of Sciences of Meknes, Laboratory of Plant Biotechnology and Molecular Biology, BP 11201, Zitoune Meknes City, Morocco.,Cluster of Competency «Agri-food, Safety and Security» IUC VLIR-UOS, Moulay Ismail University, Marjane 2, BP 298, Meknes City, Morocco
| | - Behnam Taidi
- CentraleSupélec, SFR Condorcet FR, CNRS 3417, Paris-Saclay University, European Center of Biotechnology and Bioeconomy (CEBB) - LGPM, 3 Rue des Rouges Terres, 51110, Pomacle, France
| | - Hassan Hajjaj
- Faculty of Sciences of Meknes, Laboratory of Plant Biotechnology and Molecular Biology, BP 11201, Zitoune Meknes City, Morocco.,Cluster of Competency «Agri-food, Safety and Security» IUC VLIR-UOS, Moulay Ismail University, Marjane 2, BP 298, Meknes City, Morocco
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15
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Martins-Santana L, Paula RGD, Silva AG, Lopes DCB, Silva RDN, Silva-Rocha R. CRZ1 regulator and calcium cooperatively modulate holocellulases gene expression in Trichoderma reesei QM6a. Genet Mol Biol 2020; 43:e20190244. [PMID: 32384133 PMCID: PMC7212764 DOI: 10.1590/1678-4685-gmb-2019-0244] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 12/22/2019] [Indexed: 02/06/2023] Open
Abstract
Trichoderma reesei is the main filamentous fungus used in industry to produce cellulases. Here we investigated the role of CRZ1 and Ca2+signaling in the fungus T. reesei QM6a concerning holocellulases production. For this, we first searched for potential CRZ1 binding sites in promoter regions of key genes coding holocellulases, as well as transcriptional regulators and sugar and calcium transporters. Using a nearly constructed T. reeseiAcrz1 strain, we demonstrated that most of the genes expected to be regulated by CRZ1 were affected in the mutant strain induced with sugarcane bagasse (SCB) and cellulose. In particular, our data demonstrate that Ca2+ acts synergistically with CRZ1 to modulate gene expression, but also exerts CRZ1-independent regulatory role in gene expression in T. reesei, highlighting the role of the major regulator Ca2+ on the signaling for holocellulases transcriptional control in the most part of cellulases genes here investigated. This work presents new evidence on the regulatory role of CRZ1 and Ca2+ sensing in the regulation of cellulolytic enzymes in T. reesei, evidencing significant and previously unknown function of this Ca2+sensing system in the control key transcriptional regulators (XYR1 and CRE1) and on the expression of genes related to sugar and Ca2+ transport.
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Affiliation(s)
- Leonardo Martins-Santana
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Laboratório de Biologia Sistêmica e Sintética, Ribeirão Preto, SP, Brazil.,Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Bioquímica e Imunologia, Ribeirão Preto, SP, Brazil
| | - Renato Graciano de Paula
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Bioquímica e Imunologia, Ribeirão Preto, SP, Brazil.,Universidade Federal do Espírito Santo, Centro de Ciências da Saúde, Departamento de Ciências Fisiológicas, Vitória, ES, Brazil
| | - Adriano Gomes Silva
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Laboratório de Biologia Sistêmica e Sintética, Ribeirão Preto, SP, Brazil
| | - Douglas Christian Borges Lopes
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Bioquímica e Imunologia, Ribeirão Preto, SP, Brazil
| | - Roberto do Nascimento Silva
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Bioquímica e Imunologia, Ribeirão Preto, SP, Brazil
| | - Rafael Silva-Rocha
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Laboratório de Biologia Sistêmica e Sintética, Ribeirão Preto, SP, Brazil
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16
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Wang L, Yang R, Cao Y, Zheng F, Meng X, Zhong Y, Chen G, Zhang W, Liu W. CLP1, a Novel Plant Homeo Domain Protein, Participates in Regulating Cellulase Gene Expression in the Filamentous Fungus Trichoderma reesei. Front Microbiol 2019; 10:1700. [PMID: 31447796 PMCID: PMC6691364 DOI: 10.3389/fmicb.2019.01700] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 07/10/2019] [Indexed: 01/17/2023] Open
Abstract
The stringent regulatory network of cellulase gene expression in the filamentous fungus Trichoderma reesei involves multiple transcriptional regulators. However, identification and mechanistic investigation of these regulators are still insufficient. Here, we identified a novel transcriptional regulator, CLP1, a plant homeo domain (PHD) Protein that participates in regulating T. reesei cellulase gene expression. Phylogenetic analyses demonstrated that CLP1 homologs are widely distributed in filamentous fungi including Trichoderma, Penicillium, Fusarium, Neurospora, and Aspergillus species. We demonstrated that CLP1 is a nuclear protein and lack of CLP1 significantly impaired the induced expression of cellulase genes. ChIP experiments showed CLP1 binding to the cellulase gene promoters specifically under cellulose conditions and compromised XYR1 occupancy on the same promoters in the absence of CLP1 at the early induction stage. XYR1 overexpression fully rescued the defect in cellulase production but not the defect in conidia formation in the clp1 null mutant. Further analysis showed that the PHD is required for the CLP1 appropriate subcellular localization as well as the induced cellulase gene expression and conidiation. Taken together, these data demonstrated an important role of CLP1 in the regulation of cellulase and xylanase gene expression in T. reesei.
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Affiliation(s)
- Lei Wang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Renfei Yang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Yanli Cao
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Fanglin Zheng
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Xiangfeng Meng
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Guanjun Chen
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Weixin Zhang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
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17
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A Novel Cys2His2 Zinc Finger Homolog of AZF1 Modulates Holocellulase Expression in Trichoderma reesei. mSystems 2019; 4:4/4/e00161-19. [PMID: 31213522 PMCID: PMC6581689 DOI: 10.1128/msystems.00161-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In this work, we used a systems biology approach to map new regulatory interactions in Trichoderma reesei controlling the expression of genes encoding cellulase and hemicellulase. By integrating transcriptomics related to complex biomass degradation, we were able to identify a novel transcriptional regulator which is able to activate the expression of these genes in response to two different cellulose sources. In vivo experimental validation confirmed the role of this new regulator in several other processes related to carbon source utilization and nutrient transport. Therefore, this work revealed novel forms of regulatory interaction in this model system for plant biomass deconstruction and also represented a new approach that could be easy applied to other organisms. Filamentous fungi are remarkable producers of enzymes dedicated to the degradation of sugar polymers found in the plant cell wall. Here, we integrated transcriptomic data to identify novel transcription factors (TFs) related to the control of gene expression of lignocellulosic hydrolases in Trichoderma reesei and Aspergillus nidulans. Using various sets of differentially expressed genes, we identified some putative cis-regulatory elements that were related to known binding sites for Saccharomyces cerevisiae TFs. Comparative genomics allowed the identification of six transcriptional factors in filamentous fungi that have corresponding S. cerevisiae homologs. Additionally, a knockout strain of T. reesei lacking one of these TFs (S. cerevisiaeAZF1 homolog) displayed strong reductions in the levels of expression of several cellulase-encoding genes in response to both Avicel and sugarcane bagasse, revealing a new player in the complex regulatory network operating in filamentous fungi during plant biomass degradation. Finally, RNA sequencing (RNA-seq) analysis showed the scope of the AZF1 homologue in regulating a number of processes in T. reesei, and chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) provided evidence for the direct interaction of this TF in the promoter regions of cel7a, cel45a, and swo. Therefore, we identified here a novel TF which plays a positive effect in the expression of cellulase-encoding genes in T. reesei. IMPORTANCE In this work, we used a systems biology approach to map new regulatory interactions in Trichoderma reesei controlling the expression of genes encoding cellulase and hemicellulase. By integrating transcriptomics related to complex biomass degradation, we were able to identify a novel transcriptional regulator which is able to activate the expression of these genes in response to two different cellulose sources. In vivo experimental validation confirmed the role of this new regulator in several other processes related to carbon source utilization and nutrient transport. Therefore, this work revealed novel forms of regulatory interaction in this model system for plant biomass deconstruction and also represented a new approach that could be easy applied to other organisms.
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de Paula RG, Antoniêto ACC, Nogueira KMV, Ribeiro LFC, Rocha MC, Malavazi I, Almeida F, Silva RN. Extracellular vesicles carry cellulases in the industrial fungus Trichoderma reesei. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:146. [PMID: 31223336 PMCID: PMC6570945 DOI: 10.1186/s13068-019-1487-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 06/07/2019] [Indexed: 05/21/2023]
Abstract
BACKGROUND Trichoderma reesei is the most important industrial producer of lignocellulolytic enzymes. These enzymes play an important role in biomass degradation leading to novel applications of this fungus in the biotechnology industry, specifically biofuel production. The secretory pathway of fungi is responsible for transporting proteins addressed to different cellular locations involving some cellular endomembrane systems. Although protein secretion is an extremely efficient process in T. reesei, the mechanisms underlying protein secretion have remained largely uncharacterized in this organism. RESULTS Here, we report for the first time the isolation and characterization of T. reesei extracellular vesicles (EVs). Using proteomic analysis under cellulose culture condition, we have confidently identified 188 vesicular proteins belonging to different functional categories. Also, we characterized EVs production using transmission electron microscopy in combination with light scattering analysis. Biochemical assays revealed that T. reesei extracellular vesicles have an enrichment of filter paper (FPase) and β-glucosidase activities in purified vesicles from 24, 72 and 96, and 72 and 96 h, respectively. Furthermore, our results showed that there is a slight enrichment of small RNAs inside the vesicles after 96 h and 120 h, and presence of hsp proteins inside the vesicles purified from T. reesei grown in the presence of cellulose. CONCLUSIONS This work points to important insights into a better understanding of the cellular mechanisms underlying the regulation of cellulolytic enzyme secretion in this fungus.
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Affiliation(s)
- Renato Graciano de Paula
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, São Paulo, 14049-900 Brazil
| | - Amanda Cristina Campos Antoniêto
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, São Paulo, 14049-900 Brazil
| | - Karoline Maria Vieira Nogueira
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, São Paulo, 14049-900 Brazil
| | - Liliane Fraga Costa Ribeiro
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, São Paulo, 14049-900 Brazil
| | - Marina Campos Rocha
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Paulo, Brazil
| | - Iran Malavazi
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Paulo, Brazil
| | - Fausto Almeida
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, São Paulo, 14049-900 Brazil
| | - Roberto Nascimento Silva
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, São Paulo, 14049-900 Brazil
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Wang L, Lv X, Cao Y, Zheng F, Meng X, Shen Y, Chen G, Liu W, Zhang W. A novel transcriptional regulator RXE1 modulates the essential transactivator XYR1 and cellulase gene expression in Trichoderma reesei. Appl Microbiol Biotechnol 2019; 103:4511-4523. [DOI: 10.1007/s00253-019-09739-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/26/2019] [Accepted: 03/03/2019] [Indexed: 12/20/2022]
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Vassiliadis D, Wong KH, Andrianopoulos A, Monahan BJ. A genome-wide analysis of carbon catabolite repression in Schizosaccharomyces pombe. BMC Genomics 2019; 20:251. [PMID: 30922219 PMCID: PMC6440086 DOI: 10.1186/s12864-019-5602-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 03/12/2019] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Optimal glucose metabolism is central to the growth and development of cells. In microbial eukaryotes, carbon catabolite repression (CCR) mediates the preferential utilization of glucose, primarily by repressing alternate carbon source utilization. In fission yeast, CCR is mediated by transcriptional repressors Scr1 and the Tup/Ssn6 complex, with the Rst2 transcription factor important for activation of gluconeogenesis and sexual differentiation genes upon derepression. Through genetic and genome-wide methods, this study aimed to comprehensively characterize CCR in fission yeast by identifying the genes and biological processes that are regulated by Scr1, Tup/Ssn6 and Rst2, the core CCR machinery. RESULTS The transcriptional response of fission yeast to glucose-sufficient or glucose-deficient growth conditions in wild type and CCR mutant cells was determined by RNA-seq and ChIP-seq. Scr1 was found to regulate genes involved in carbon metabolism, hexose uptake, gluconeogenesis and the TCA cycle. Surprisingly, a role for Scr1 in the suppression of sexual differentiation was also identified, as homothallic scr1 deletion mutants showed ectopic meiosis in carbon and nitrogen rich conditions. ChIP-seq characterised the targets of Tup/Ssn6 and Rst2 identifying regulatory roles within and independent of CCR. Finally, a subset of genes bound by all three factors was identified, implying that regulation of certain loci may be modulated in a competitive fashion between the Scr1, Tup/Ssn6 repressors and the Rst2 activator. CONCLUSIONS By identifying the genes directly and indirectly regulated by Scr1, Tup/Ssn6 and Rst2, this study comprehensively defined the gene regulatory networks of CCR in fission yeast and revealed the transcriptional complexities governing this system.
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Affiliation(s)
- Dane Vassiliadis
- Genetics, Genomics & Systems Biology, School of Biosciences, The University of Melbourne, Parkville, Victoria, Australia. .,Commonwealth Scientific and Industrial Research Organisation (CSIRO), Parkville, Victoria, Australia.
| | - Koon Ho Wong
- Faculty of Health Sciences, University of Macau, Macau, China.,Institute of Translational Medicine, University of Macau, Macau, China
| | - Alex Andrianopoulos
- Genetics, Genomics & Systems Biology, School of Biosciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Brendon J Monahan
- Genetics, Genomics & Systems Biology, School of Biosciences, The University of Melbourne, Parkville, Victoria, Australia. .,Commonwealth Scientific and Industrial Research Organisation (CSIRO), Parkville, Victoria, Australia. .,Cancer Therapeutics (CTx), Parkville, Victoria, Australia.
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The Duality of the MAPK Signaling Pathway in the Control of Metabolic Processes and Cellulase Production in Trichoderma reesei. Sci Rep 2018; 8:14931. [PMID: 30297963 PMCID: PMC6175961 DOI: 10.1038/s41598-018-33383-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 09/27/2018] [Indexed: 01/09/2023] Open
Abstract
In this study, through global transcriptional analysis by RNA-Sequencing, we identified the main changes in gene expression that occurred in two functional mutants of the MAPK genes tmk1 and tmk2 in Trichoderma reesei during sugarcane bagasse degradation. We found that the proteins encoded by these genes regulated independent processes, sometimes in a cross-talk manner, to modulate gene expression in T. reesei. In the Δtmk2 strain, growth in sugarcane bagasse modulated the expression of genes involved in carbohydrate metabolism, cell growth and development, and G-protein-coupled receptor-mediated cell signaling. On the other hand, deletion of tmk1 led to decreased expression of the major genes for cellulases and xylanases. Furthermore, TMK1 found to be involved in the regulation of the expression of major facilitator superfamily transporters. Our results revealed that the MAPK signaling pathway in T. reesei regulates many important processes that allow the fungus to recognize, transport, and metabolize different carbon sources during plant cell wall degradation.
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New Genomic Approaches to Enhance Biomass Degradation by the Industrial Fungus Trichoderma reesei. Int J Genomics 2018; 2018:1974151. [PMID: 30345291 PMCID: PMC6174759 DOI: 10.1155/2018/1974151] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 06/20/2018] [Accepted: 07/29/2018] [Indexed: 11/17/2022] Open
Abstract
The filamentous fungi Trichoderma reesei is one of the most well-studied cellulolytic microorganisms. It is the most important fungus for the industrial production of enzymes to biomass deconstruction being widely used in the biotechnology industry, mainly in the production of biofuels. Here, we performed an analytic review of the holocellulolytic system presented by T. reesei as well as the transcriptional and signaling mechanisms involved with holocellulase expression in this fungus. We also discuss new perspectives about control of secretion and cellulase expression based on RNA-seq and functional characterization data of T. reesei growth in different carbon sources, which comprise glucose, cellulose, sophorose, and sugarcane bagasse.
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The Aspergillus nidulans Pyruvate Dehydrogenase Kinases Are Essential To Integrate Carbon Source Metabolism. G3-GENES GENOMES GENETICS 2018; 8:2445-2463. [PMID: 29794164 PMCID: PMC6027865 DOI: 10.1534/g3.118.200411] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The pyruvate dehydrogenase complex (PDH), that converts pyruvate to acetyl-coA, is regulated by pyruvate dehydrogenase kinases (PDHK) and phosphatases (PDHP) that have been shown to be important for morphology, pathogenicity and carbon source utilization in different fungal species. The aim of this study was to investigate the role played by the three PDHKs PkpA, PkpB and PkpC in carbon source utilization in the reference filamentous fungus Aspergillus nidulans, in order to unravel regulatory mechanisms which could prove useful for fungal biotechnological and biomedical applications. PkpA and PkpB were shown to be mitochondrial whereas PkpC localized to the mitochondria in a carbon source-dependent manner. Only PkpA was shown to regulate PDH activity. In the presence of glucose, deletion of pkpA and pkpC resulted in reduced glucose utilization, which affected carbon catabolite repression (CCR) and hydrolytic enzyme secretion, due to de-regulated glycolysis and TCA cycle enzyme activities. Furthermore, PkpC was shown to be required for the correct metabolic utilization of cellulose and acetate. PkpC negatively regulated the activity of the glyoxylate cycle enzyme isocitrate lyase (ICL), required for acetate metabolism. In summary, this study identified PDHKs important for the regulation of central carbon metabolism in the presence of different carbon sources, with effects on the secretion of biotechnologically important enzymes and carbon source-related growth. This work demonstrates how central carbon metabolism can affect a variety of fungal traits and lays a basis for further investigation into these characteristics with potential interest for different applications.
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Gao J, Qian Y, Wang Y, Qu Y, Zhong Y. Production of the versatile cellulase for cellulose bioconversion and cellulase inducer synthesis by genetic improvement of Trichoderma reesei. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:272. [PMID: 29167702 PMCID: PMC5688634 DOI: 10.1186/s13068-017-0963-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 11/07/2017] [Indexed: 05/05/2023]
Abstract
BACKGROUND The enzymes for efficient hydrolysis of lignocellulosic biomass are a major factor in the development of an economically feasible cellulose bioconversion process. Up to now, low hydrolysis efficiency and high production cost of cellulases remain the significant hurdles in this process. The aim of the present study was to develop a versatile cellulase system with the enhanced hydrolytic efficiency and the ability to synthesize powerful inducers by genetically engineering Trichoderma reesei. RESULTS In our study, we employed a systematic genetic strategy to construct the carbon catabolite-derepressed strain T. reesei SCB18 to produce the cellulase complex that exhibited a strong cellulolytic capacity for biomass saccharification and an extraordinary high β-glucosidase (BGL) activity for cellulase-inducing disaccharides synthesis. We first identified the hypercellulolytic and uracil auxotrophic strain T. reesei SP4 as carbon catabolite repressed, and then deleted the carbon catabolite repressor gene cre1 in the genome. We found that the deletion of cre1 with the selectable marker pyrG led to a 72.6% increase in total cellulase activity, but a slight reduction in saccharification efficiency. To facilitate the following genetic modification, the marker pyrG was successfully removed by homologous recombination based on resistance to 5-FOA. Furthermore, the Aspergillus niger BGLA-encoding gene bglA was overexpressed, and the generated strain T. reesei SCB18 exhibited a 29.8% increase in total cellulase activity and a 51.3-fold enhancement in BGL activity (up to 103.9 IU/mL). We observed that the cellulase system of SCB18 showed significantly higher saccharification efficiency toward differently pretreated corncob residues than the control strains SDC11 and SP4. Moreover, the crude enzyme preparation from SCB18 with high BGL activity possessed strong transglycosylation ability to synthesize β-disaccharides from glucose. The transglycosylation product was finally utilized as the inducer for cellulase production, which provided a 63.0% increase in total cellulase activity compared to the frequently used soluble inducer, lactose. CONCLUSIONS In summary, we constructed a versatile cellulase system in T. reesei for efficient biomass saccharification and powerful cellulase inducer synthesis by combinational genetic manipulation of three distinct types of genes to achieve the customized cellulase production, thus providing a viable strategy for further strain improvement to reduce the cost of biomass-based biofuel production.
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Affiliation(s)
- Jia Gao
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100 People’s Republic of China
| | - Yuanchao Qian
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100 People’s Republic of China
| | - Yifan Wang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100 People’s Republic of China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100 People’s Republic of China
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100 People’s Republic of China
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Cao Y, Zheng F, Wang L, Zhao G, Chen G, Zhang W, Liu W. Rce1, a novel transcriptional repressor, regulates cellulase gene expression by antagonizing the transactivator Xyr1 in Trichoderma reesei. Mol Microbiol 2017; 105:65-83. [PMID: 28378498 DOI: 10.1111/mmi.13685] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/27/2017] [Indexed: 11/28/2022]
Abstract
Cellulase gene expression in the model cellulolytic fungus Trichoderma reesei is supposed to be controlled by an intricate regulatory network involving multiple transcription factors. Here, we identified a novel transcriptional repressor of cellulase gene expression, Rce1. Disruption of the rce1 gene not only facilitated the induced expression of cellulase genes but also led to a significant delay in terminating the induction process. However, Rce1 did not participate in Cre1-mediated catabolite repression. Electrophoretic mobility shift (EMSA) and DNase I footprinting assays in combination with chromatin immunoprecipitation (ChIP) demonstrated that Rce1 could bind directly to a cbh1 (cellobiohydrolase 1-encoding) gene promoter region containing a cluster of Xyr1 binding sites. Furthermore, competitive binding assays revealed that Rce1 antagonized Xyr1 from binding to the cbh1 promoter. These results indicate that intricate interactions exist between a variety of transcription factors to ensure tight and energy-efficient regulation of cellulase gene expression in T. reesei. This study also provides important clues regarding increased cellulase production in T. reesei.
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Affiliation(s)
- Yanli Cao
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No. 27 Shanda South Road, Jinan, Shandong, 250100, P. R. China
| | - Fanglin Zheng
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No. 27 Shanda South Road, Jinan, Shandong, 250100, P. R. China
| | - Lei Wang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No. 27 Shanda South Road, Jinan, Shandong, 250100, P. R. China
| | - Guolei Zhao
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No. 27 Shanda South Road, Jinan, Shandong, 250100, P. R. China
| | - Guanjun Chen
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No. 27 Shanda South Road, Jinan, Shandong, 250100, P. R. China
| | - Weixin Zhang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No. 27 Shanda South Road, Jinan, Shandong, 250100, P. R. China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, No. 27 Shanda South Road, Jinan, Shandong, 250100, P. R. China
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da Silva Delabona P, Rodrigues GN, Zubieta MP, Ramoni J, Codima CA, Lima DJ, Farinas CS, da Cruz Pradella JG, Seiboth B. The relation between xyr1 overexpression in Trichoderma harzianum and sugarcane bagasse saccharification performance. J Biotechnol 2017; 246:24-32. [DOI: 10.1016/j.jbiotec.2017.02.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 01/09/2017] [Accepted: 02/02/2017] [Indexed: 01/16/2023]
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Dos Santos Castro L, de Paula RG, Antoniêto ACC, Persinoti GF, Silva-Rocha R, Silva RN. Understanding the Role of the Master Regulator XYR1 in Trichoderma reesei by Global Transcriptional Analysis. Front Microbiol 2016; 7:175. [PMID: 26909077 PMCID: PMC4754417 DOI: 10.3389/fmicb.2016.00175] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 02/01/2016] [Indexed: 11/13/2022] Open
Abstract
We defined the role of the transcriptional factor—XYR1—in the filamentous fungus Trichoderma reesei during cellulosic material degradation. In this regard, we performed a global transcriptome analysis using RNA-Seq of the Δxyr1 mutant strain of T. reesei compared with the parental strain QM9414 grown in the presence of cellulose, sophorose, and glucose as sole carbon sources. We found that 5885 genes were expressed differentially under the three tested carbon sources. Of these, 322 genes were upregulated in the presence of cellulose, while 367 and 188 were upregulated in sophorose and glucose, respectively. With respect to genes under the direct regulation of XYR1, 30 and 33 are exclusive to cellulose and sophorose, respectively. The most modulated genes in the Δxyr1 belong to Carbohydrate-Active Enzymes (CAZymes), transcription factors, and transporters families. Moreover, we highlight the downregulation of transporters belonging to the MFS and ABC transporter families. Of these, MFS members were mostly downregulated in the presence of cellulose. In sophorose and glucose, the expression of these transporters was mainly upregulated. Our results revealed that MFS and ABC transporters could be new players in cellulose degradation and their role was shown to be carbon source-dependent. Our findings contribute to a better understanding of the regulatory mechanisms of XYR1 to control cellulase gene expression in T. reesei in the presence of cellulosic material, thereby potentially enhancing its application in several biotechnology fields.
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Affiliation(s)
- Lilian Dos Santos Castro
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo Ribeirão Preto, Brazil
| | - Renato G de Paula
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo Ribeirão Preto, Brazil
| | - Amanda C C Antoniêto
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo Ribeirão Preto, Brazil
| | - Gabriela F Persinoti
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol, Centro Nacional de Pesquisa em Energia e Materiais Campinas, Brazil
| | - Rafael Silva-Rocha
- Systems and Synthetic Biology Laboratory, Department of Cell and Molecular Biology, Ribeirão Preto Medical School, University of São Paulo Ribeirão Preto, Brazil
| | - Roberto N Silva
- Molecular Biotechnology Laboratory, Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo Ribeirão Preto, Brazil
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