Affiliation:
1. National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
Abstract
Antrodia cinnamomea (AC), a rare fungus endemic to Taiwan, contains high levels of various secondary metabolites, notably triterpenoids, having useful medicinal and pharmacological properties. Techniques for increasing the production of AC triterpenoids (ACT) for medicinal purposes are a high research priority. We measured and compared the biomass and ACT content of AC mycelia under various liquid fermentation culture conditions. Relative gene expression levels of ten enzymes involved in the mevalonate (MVA) pathway and “subsequent group modification pathway” were determined, and correlation analysis was performed to evaluate the roles of these enzyme genes in ACT synthesis. Two representative genes encoding the enzymes lanosterol synthase (AcLSS) and sterol C-24 reductase (AcERG4), whose activity is closely associated with ACT content, were selected for homologous expression. AcLSS and AcERG4 were separately linked to plasmid pCT74, and transformed into prepared AC protoplasts to obtain two recombinant strains, termed RpLSS and RpERG4, by polyethylene glycol (PEG)-CaCl2-mediated protoplast transformation. Upregulated expression levels of AcLSS and AcERG4 (1.78- and 1.41-fold, respectively) were associated with significantly higher (1.82- and 1.37-fold, respectively) ACT content in the recombinant strains in comparison with the wild-type. Our findings provide a theoretical and practical basis for the enhancement of ACT production using homologous expression techniques.
Funder
National Natural Science Foundation of China
Program of Scientific and Technological Talents Service to Business of Hubei Province
Subject
Plant Science,Biochemistry, Genetics and Molecular Biology (miscellaneous),Food Science