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Updated: May 21, 2026
13:05
Expression of Recombinant Cellulase Cel5A from Trichoderma reesei in Tobacco Plants
Published on: June 13, 2014
Achieving efficient protein expression in Trichoderma reesei by using strong constitutive promoters
Junxin Li1, Juan Wang, Shaowen Wang
1College of Life Science, Shenzhen Key Laboratory of Microbial Genetic Engineering, Shenzhen University, Shenzhen 518060, China.
Microbial Cell Factories
|June 20, 2012
Summary
Researchers identified novel constitutive promoters in Trichoderma reesei for high-level xylanase II expression. This method bypasses inducible promoters, enabling efficient recombinant protein production.
Area of Science:
- Microbiology
- Molecular Biology
- Biotechnology
Background:
- Trichoderma reesei is a key fungus for gene expression, commonly using the inducible cbh1 promoter.
- Constitutive promoters offer advantages over inducible ones by avoiding unwanted byproducts like cellulase components.
Purpose of the Study:
- To screen for and identify constitutive promoters in T. reesei.
- To achieve high-level homologous expression of xylanase II using identified constitutive promoters.
Main Methods:
- Quantitative real-time reverse-transcription polymerase chain reaction (RT-qPCR) was used to analyze transcriptional profiles of 13 glucose metabolism genes.
- Recombinant T. reesei strains were constructed using pdc and eno gene promoters for homologous xylanase II expression.
Main Results:
- The pyruvate decarboxylase (pdc) and enolase (eno) genes showed significantly higher mRNA levels under high glucose conditions.
- Xylanase II expression reached 9266 IU/ml (pdc promoter) and 8866 IU/ml (eno promoter), with productivities of 1.61 g/L and 1.52 g/L, respectively.
- These productivities represented approximately 83% and 82% of total secreted protein.
Conclusions:
- Constitutive promoters were successfully screened in T. reesei using RT-qPCR.
- The highest expression of recombinant xylanase II to date was achieved using these novel constitutive promoters.
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