dients in G. lucidum has turn into a crucial situation. The key active components of G. lucidum are polysaccharides and G. lucidum triterpenes (GLTs), which have immune regulation and antitumour effects (Tianet al. 2021; Shao et al. 2020; Do et al. 2021; Zhang et al. 2021a, b, c; IL-17 Inhibitor Species Bharadwaj et al. 2019). G. lucidum will be the fungus with all the most triterpenoids, and much more than 250 triterpenoid compounds have already been identified from this species. Nevertheless, compared with plants, we know somewhat small with regards to the biosynthesis of triterpenoid compounds in basidiomycetes (Wang et al. 2020a, b, c). It has been determined that the main terpene element in G. lucidum is ganoderic acid (GA) (Shao et al. 2020; Liang et al. 2019), and much more than 170 types of GA have already been isolated from G. lucidum (Wang et al. 2021). Notably, all triterpenoid compounds in G. lucidum are tetracyclic triterpenoids (Bhat et al. 2019), as well as the chemical structure of G. lucidum triterpenoid compounds is according to lanolin sterane. Lanolin is actually a metabolite of lanosterol, and lanosterol is formed by cyclization of squalene (Liang et al. 2019). In 2003, Shiao et al. (2003) confirmed by way of the isotope IL-13 Inhibitor drug labelling approach that the terpenes in G. lucidum were certainly synthesized through the MVA pathway. The biosynthetic pathway of triterpenoids has been preliminarily characterized. To enhance the yield of GA, scientists have conducted a big number of studies on the key enzyme genes involved in its biosynthesis. Scientists applied succinate dehydrogenase B (SDHB) as a selectable marker for the first time for you to establish a homologous genetic transformation program for G. lucidum. The Agrobacterium tumefaciens transformation method was utilized to overexpress the HMGR gene. Final results showed that the overexpression of HMGR doubled the content of GA and simultaneously elevated the accumulation of squalene and lanosterol (Xu et al. 2012). To establish the part of MVD within the biosynthesis of GA, scientists have employed homologous FPS to overexpress GA, which effectively increases the production of GA but in addition outcomes in enhanced expression of squalene synthase (SQS) and lanosterol synthase (LS). The SQS and LS transcription levels were upregulated 2.28- and 1.73-fold, respectively (Fei et al. 2019). In addition, Agrobacterium tumefaciens was employed to mediate the transformation of G. lucidum, and Gl-MVD overexpression transformants were screened by PCR. The data showed that the transcripts had been all overexpressed, and their triterpene content elevated by roughly 1701.four (Shi et al. 2012). These final results highlighted that MVD plays a essential function inside the biosynthesis of GA. Squalene epoxidase is a form of biocatalyst. To study its effect on the biosynthetic pathway of GA, the SE gene was cloned from G. lucidum and overexpressed. The study discovered that SE was overexpressed, plus the content material of GA produced by the strain was two times that from the wild-type strain (Zhang et al. 2017a, b, c). This outcome indicates that the SE gene stimulates the biosynthesis of GA. In this study, SE and HMGR genes had been simultaneouslyWang et al. AMB Expr(2021) 11:Web page 10 ofand strongly expressed. The results of your experiment discovered that the co-expressed strain had a greater acid content material than the GA content material with the single expressed strain (Zhang et al. 2017a, b, c), which proved that the joint coexpression in the two genes promoted GA biosynthesis. This study gives an effective basis for the biosynthesis of GA. Lanosterol synthas