Production and characterization of cellulolytic enzymes from Trichoderma reesei grown on various carbon sources

ABSTRACT Lactose (1,4- O -β- d -galacto-pyranosyl- d -glucose) induces cellulolytic enzymes in Trichoderma reesei and is in fact one of the most important soluble carbon sources used to produce cellulases on an industrial level. The mechanism underlying the induction is, however, not fully understood. In this study, we investigated the cellular functions of the intracellular β-glucosidases CEL1a and CEL1b in the induction of cellulase genes by lactose in T. reesei . We demonstrated that while CEL1a and CEL1b were functionally equivalent in mediating the induction, the simultaneous absence of these intracellular β-glucosidases abolished cbh1 gene expression on lactose. d -Galactose restored the efficient cellulase gene induction in the Δ cel1a strain independently of its reductive metabolism, but not in the Δ cel1a Δ cel1b strain. A further comparison of the transcriptional responses of the Δ cel1a Δ cel1b strain complemented with wild-type CEL1a or a catalytically inactive CEL1a version and the Δ cel1a strain constitutively expressing CEL1a or the Kluyveromyces lactis β-galactosidase LAC4 showed that both the CEL1a protein and its glycoside hydrolytic activity were indispensable for cellulase induction by lactose. We also present evidence that intracellular β-glucosidase-mediated lactose induction is further conveyed to XYR1 to ensure the efficiently induced expression of cellulase genes.

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Characterization of cellulases and hemicellulases produced by Trichoderma reesei on various carbon sources

Process Biochemistry ◽

10.1016/j.procbio.2005.03.057 ◽

2005 ◽

Vol 40 (11) ◽

pp. 3519-3525 ◽

Cited By ~ 168

Author(s):

T. Juhász ◽

Z. Szengyel ◽

K. Réczey ◽

M. Siika-Aho ◽

L. Viikari

Keyword(s):

Trichoderma Reesei ◽

Carbon Sources

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Identification and characterization of a novel gene, TrCCD1, and its possible function in hyphal growth and conidiospore development of Trichoderma reesei

Fungal Genetics and Biology ◽

10.1016/j.fgb.2008.12.006 ◽

2009 ◽

Vol 46 (3) ◽

pp. 255-263 ◽

Cited By ~ 6

Author(s):

Yao Hua Zhong ◽

Tian Hong Wang ◽

Xiao Li Wang ◽

Guang Tao Zhang ◽

Hai Na Yu

Keyword(s):

Trichoderma Reesei ◽

Hyphal Growth ◽

Novel Gene ◽

Identification And Characterization

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Consolidated Bioprocessing: Synthetic Biology Routes to Fuels and Fine Chemicals

Microorganisms ◽

10.3390/microorganisms9051079 ◽

2021 ◽

Vol 9 (5) ◽

pp. 1079

Author(s):

Alec Banner ◽

Helen S. Toogood ◽

Nigel S. Scrutton

Keyword(s):

Enzymatic Degradation ◽

Consolidated Bioprocessing ◽

Carbon Sources ◽

Cellulolytic Enzymes ◽

Waste Biomass ◽

Chemical Production ◽

Iterative Design ◽

Biomass Feedstocks ◽

Advanced Fuels ◽

Design Build

The long road from emerging biotechnologies to commercial “green” biosynthetic routes for chemical production relies in part on efficient microbial use of sustainable and renewable waste biomass feedstocks. One solution is to apply the consolidated bioprocessing approach, whereby microorganisms convert lignocellulose waste into advanced fuels and other chemicals. As lignocellulose is a highly complex network of polymers, enzymatic degradation or “saccharification” requires a range of cellulolytic enzymes acting synergistically to release the abundant sugars contained within. Complications arise from the need for extracellular localisation of cellulolytic enzymes, whether they be free or cell-associated. This review highlights the current progress in the consolidated bioprocessing approach, whereby microbial chassis are engineered to grow on lignocellulose as sole carbon sources whilst generating commercially useful chemicals. Future perspectives in the emerging biofoundry approach with bacterial hosts are discussed, where solutions to existing bottlenecks could potentially be overcome though the application of high throughput and iterative Design-Build-Test-Learn methodologies. These rapid automated pathway building infrastructures could be adapted for addressing the challenges of increasing cellulolytic capabilities of microorganisms to commercially viable levels.

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Electrophysiological characterization of a diverse group of sugar transporters from Trichoderma reesei

Scientific Reports ◽

10.1038/s41598-021-93552-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sami Havukainen ◽

Jonai Pujol-Giménez ◽

Mari Valkonen ◽

Ann Westerholm-Parvinen ◽

Matthias A. Hediger ◽

...

Keyword(s):

Trichoderma Reesei ◽

Scientific Literature ◽

Large Body ◽

Comprehensive Analysis ◽

Transport Function ◽

Sugar Transporters ◽

New Knowledge ◽

Electrophysiological Characterization ◽

Shed Light

AbstractTrichoderma reesei is an ascomycete fungus known for its capability to secrete high amounts of extracellular cellulose- and hemicellulose-degrading enzymes. These enzymes are utilized in the production of second-generation biofuels and T. reesei is a well-established host for their production. Although this species has gained considerable interest in the scientific literature, the sugar transportome of T. reesei remains poorly characterized. Better understanding of the proteins involved in the transport of different sugars could be utilized for engineering better enzyme production strains. In this study we aimed to shed light on this matter by characterizing multiple T. reesei transporters capable of transporting various types of sugars. We used phylogenetics to select transporters for expression in Xenopus laevis oocytes to screen for transport activities. Of the 18 tested transporters, 8 were found to be functional in oocytes. 10 transporters in total were investigated in oocytes and in yeast, and for 3 of them no transport function had been described in literature. This comprehensive analysis provides a large body of new knowledge about T. reesei sugar transporters, and further establishes X. laevis oocytes as a valuable tool for studying fungal sugar transporters.

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