Trichoderma reesei

About: Trichoderma reesei is a research topic. Over the lifetime, 3832 publications have been published within this topic receiving 152877 citations. The topic is also known as: Trichoderma reesi.

Cellulase hyper-production by Trichoderma reesei mutant SEU-7 on lactose

Abstract: The induction of cellulase production by insoluble carbon source cellulose was a common and efficient strategy, but has some drawbacks, such as difficult fermentation operation, substantial cellulase loss, long fermentation time, and high energy-consumption, resulting in high cost of cellulase production in industry. These drawbacks can be overcome if soluble carbon sources are utilized as the inducers for cellulase production. However, until now the induction efficiency of most soluble carbon sources, especially lactose and glucose, is still inferior to cellulose despite extensive efforts have been made by either optimizing the fermentation process or constructing the recombinant strains. Therefore, strain improvement by metabolic engineering for high induction efficiency of soluble carbon sources is of great interest. Trichoderma reesei mutant SEU-7 was constructed from T. reesei RUT-C30 with the overexpression of endogenous gene β-glucosidase (BGL1) by insertional mutagenesis via Agrobacterium tumefaciens-mediated transformation (AMT). Compared to RUT-C30, SEU-7 displays substantially enhanced activities of both cellulase and hemicellulase when grown on either lactose or cellulose. The induction efficiency with lactose was found to be higher than cellulose in strain SEU-7. To the best of our knowledge, we achieved the highest FPase activity in SEU-7 in both batch culture (13.0 IU/mL) and fed-batch culture (47.0 IU/mL) on lactose. Moreover, SEU-7 displayed unrivaled pNPGase activity on lactose in both batch culture (81.0 IU/mL) and fed-batch culture (144.0 IU/mL) as compared to the other reported T. reesei strains in the literature grown in batch or fed-batch experiments on cellulose or lactose. This superiority of SEU-7 over RUT-C30 improves markedly the saccharification ability of SEU-7 on pretreated corn stover. The overexpression of gene BGL1 was found either at the mRNA or at the protein level in the mutant strains with increased cellulase production in comparison with RUT-C30, but only SEU-7 displayed much higher expression of gene BGL1 on lactose than on cellulose. Two copies of gene BGL1 were inserted into the chromosome of T. reesei SEU-7 between KI911141.1:347357 and KI911141.1:347979, replacing the original 623-bp fragment that is not within any genes’ coding region. The qRT-PCR analysis revealed that the mRNA levels of both cellulase and hemicellulase were upregulated significantly in SEU-7, together with the MFS transporter CRT1 and the XYR1 nuclear importer KAP8. Recombinant T. reesei SEU-7 displays hyper-production of both cellulase and hemicellulase on lactose with the highest FPase activity and pNPGase activity for T. reesei, enabling highly efficient saccharification of pretreated biomass. For the first time, the induction efficiency for cellulase production by lactose in T. reesei was reported to be higher than that by cellulose. This outperformance of T. reesei SEU-7, which is strain-specific, is attributed to both the overexpression of gene BGL and the collateral mutation. Moreover, the increased transcription levels of cellulase genes, the related transcription factors, and the MFS transporter CRT1 contribute to the outstanding cellulase production of SEU-7. Our research advances strain improvement to enhance the induction efficiency of soluble carbon sources to produce cost-effective cellulase and hemicellulase in industry.

Engineering enhanced cellobiohydrolase activity.

Abstract: Glycoside Hydrolase Family 7 cellobiohydrolases (GH7 CBHs) catalyze cellulose depolymerization in cellulolytic eukaryotes, making them key discovery and engineering targets. However, there remains a lack of robust structure-activity relationships for these industrially important cellulases. Here, we compare CBHs from Trichoderma reesei (TrCel7A) and Penicillium funiculosum (PfCel7A), which exhibit a multi-modular architecture consisting of catalytic domain (CD), carbohydrate-binding module, and linker. We show that PfCel7A exhibits 60% greater performance on biomass than TrCel7A. To understand the contribution of each domain to this improvement, we measure enzymatic activity for a library of CBH chimeras with swapped subdomains, demonstrating that the enhancement is mainly caused by PfCel7A CD. We solve the crystal structure of PfCel7A CD and use this information to create a second library of TrCel7A CD mutants, identifying a TrCel7A double mutant with near-equivalent activity to wild-type PfCel7A. Overall, these results reveal CBH regions that enable targeted activity improvements.

Cellulose and hemicellulose

Abstract: Cellulose. Preparation of Cellulosic Substrates: Increasing the Availability of Cellulose in Biomass Materials. Cadoxen Solvolysis of Cellulose. Preparation of Crystalline, Amorphous, and Dyed Cellulase Substrates. Preparation of Cellodextrins. Preparation of Cellodextrins: Another Perspective. Fluorogenic and Chromogenic Glycosides as Substrates and Ligands of Carbohydrases. Use of Complex Formation between Congo Red and Polysaccharides in Detection and Assay of Polysaccharide Hydrolases. Soluble, Dye-Labeled Polysaccharides for the Assay of Endohydrolases. Assays for Cellulolytic Enzymes: Methods for Measuring Cellulase Activities. Cellulase Assay Based on Cellobiose Dehydrogenase. Nephelometric and Turbidometric Assay for Cellulase. Selective Assay for Exo-1,4-/-Glucosidases. Viscosimetric Determination of Carboxymethylcellulase Activity. Staining Techniques for the Detection of the Individual Components of Cellulolytic Enzyme Systems. Chromatographic Methods for Carbohydrates: Liquid Chromatography of Carbohydrate Monomers and Oligomers. Quantitative Thin-Layer Chromatography of Sugars, Sugar Acids, and Polyalcohols. High-Performance Thin-Layer Chromatography of Starch, Cellulose, Xylan, and Chitin Hydrolyzates. Miscellaneous Methods for Cellulolytic Enzymes: Screening of Prokaryotes for Cellulose- and Hemicellulose-Degrading Enzymes. Chromatographic Separation of Cellulolytic Enzymes. Morphological Aspects of Wood Degradation. Purification of Cellulose-Degrading Enzymes: Cellulases of Pseudomonas fluorescens var. cellulosa. Cellulases of Cellulomonas uda. Cellulase of Ruminococcus albus. Cellulase of Trichoderma koningii. Cellulases of Trichoderma reesei. Cellulases of a Mutant Strain of Trichoderma viride QM 9414. Cellulases from Eupenicillium javanicum. Gentaro Okada, Cellulase of Aspergillus niger. Cellulase and Hemicellulase from Aspergillus fumigatus Fresenius. Cellulases of Aspergillus aculeatus. Cellulases from Thermoascus aurantiacus. 1,4-/-*xD-Glucan Cellobiohydrolase from Sclerotium rolfsii. Cellulases of Thermomonospora fusca. Cellulases of Humicola insolens and Humicola grisea. Cellulase-Hemicellulase Complex of Phoma hibernica. Cellulases from Sporocytophaga myxococcoides. Cellulases in Phaseolus vulgaris. Endoglucanase from Clostridium thermocellum. Crystalline Endoglucanase D of Clostridium thermocellum Overproduced in Escherichia coli. Isolation of 1,4-/-*xD-Glucan 4-Glucanohydrolases of Talaromyces emersonii. Endo-1,4-/-Glucanases of Sporotrichum pulverulentum. Carboxymethylcellulase from Sclerotium rolfsii. /-Glucanases from Pisum sativum. Cellobiosidase from Ruminococcus albus. Cellobiohydrolases of Penicillium pinophilum. Exocellulase of Irpex lacteus (Polyporus tulupiferae). /-Glucosidase from Ruminococcus albus. 1,4-/-Glucosidases of Sporotrichum pulverulentum. /-*xD-Glucosidases from Sclerotium rolfsii. Purification and Assay of /-Glucosidase from Schizophyllum commune. Purification of /-*xD-Glucoside Glucohydrolases of Talaromyces emersonii. Cellobiose Dehydrogenase from Sporotrichum thermophile. Cellobiose Dehydrogenase from Sclerotium rolfsii. Cellobiose Dehydrogenase Produced by Monilia. Cellobiose Dehydrogenase (Quinone). Cellobiose Phosphorylase from Cellvibrio gilvus. Cellulosomes from Clostridium thermocellum. Macrocellulase Complexes and Yellow Affinity Substance from Clostridium thermocellum. Acid Proteases from Sporotrichum pulverulentum. Hemicellulose. Preparation of Substrates for Hemicellulases: Purification of (1-3),(1-4)-/-Glucan from Barley Flour. Synthesis of /-*xD-Mannopyranosides for the Assay of /-*xD-Mannosidase and Exo-/-*xD-mannanase. Enzymatic Preparation of /-1,4-Mannooligosaccharides and /-1,4-Glucomannooligosaccharides. Carob and Guar Galactomannans. Xylobiose and Xylooligomers. Remazol Brilliant Blue-Xylan: A Soluble Chromogenic Substrate for Xylanases. Preparation of *xL-Arabinan and 1,5-*xL-Arabinan. Analysis of /-Glucan and Enzyme Assays: Measurement of (1-3),(1-4)-/-*xD-Glucan. Measurement of Acetylxylan Esterase in Streptomyces. 4-O-Methyl-*ga-*xD-Glucuronidase Component of Xylanolytic Complexes. Lichenase from Bacillus subtilis. Purification of /-*xD-Glucosidase from Aspergillus niger. Exo-1,4-/-Mannanase from Aeromonas hydrophila. Exo-/-*xD-mannanase from Cyamopsis tetragonolobus GuarSeed. /-*xD-Mannanase. /-Mannanase of Streptomyces. /-*xD-Mannosidase from Helix pomatia. *ga-Mannanase from Rhodococcus erythropolis. *ga-*xD-Galactosidase from Lucerne and GuarSeed. Xylanase of Bacillus pumilus. Xylanase of Cryptococcus albidus. Xylanases of Streptomyces. Xylanases of Alkalophilic Thermophilic Bacillus. Xylanase A of Schizophyllum commune. Xylanases and /-Xylosidase of Trichoderma lignorum. Xylanase of Malbranchea pulchella var. sulfurea. Xylanase of Talaromyces byssochlamydoides. 1,4-/-*xD-Xylan Xylohydrolase of Sclerotium rolfsii. /-Xylosidases of Several Fungi. /-Xylosidase//-Glucosidase of Chaetomium trilaterale. Acetylxylan Esterase of Schizophyllum commune. *ga-*xL-Arabinofuranosidase from Aspergillus niger. *ga-*xL-Arabinofuranosidase from Scopolia japonica. Arabinogalactanase of Bacillus subtilis var. amylosacchariticus. Author Index. Subject Index.

Original Article Effect of different carbon sources on cellulase production by Hypocrea jecorina (Trichoderma reesei) strains

Abstract: The ascomycete Hypocrea jecorina, an industrial (hemi)cellulase producer, can efficiently degrade plant polysaccharides. At present, the biology underlying cellulase hyperproduction of T. reesei, and the conditions for the enzyme induction, are not completely understood. In the current study, three different strains of T. reesei, including QM6a (wild-type), and mutants QM9414 and RUT-C30, were grown on 7 soluble and 7 insoluble carbon sources, with the later group including 4 pure polysaccharides and 3 lignocelluloses. Time course experiments showed that maxi- mum cellulase activity of QM6a and QM9414 strains, for the majority of tested carbon sources, occurred at 120 hrs, while RUT-C30 had the greatest cellulase activity around 72 hrs. Maximum cellulase production was observed to be 0.035, 0.42 and 0.33 µmol glucose equivalents using microcrystalline celluloses for QM6a, QM9414, and RUTC-30, respectively. Increased cellulase production was positively correlated in QM9414 and negatively correlated in RUT- C30 with ability to grow on microcrystalline cellulose.